Keywords Abstract
Kabre, Chitrarekha. "A Computer Aided Design Model for Climate Responsive Dwelling Roof." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 315-332. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Computer-Aided Design models have generated new possibilities in the sustainable design of buildings. Computer models assisting different aspects of architectural design have been developed and used for several decades. A review of contributions of computing to architectural design is given by Gero. Most of the conventional simulation computer programs do not actively support design development and optimization, specially at the formative design stages. It is well established that most decisions that affect comfort and building energy use occur during the formative design stages of the project. Furthermore, the efforts required to implement those decisions at the beginning of the design process are small compared to the effort that would be necessary later on in the design process. Therefore, if sustainable design issues are going to receive an appropriate level of consideration at the beginning of the design process, they must be presented in a way which is useful to the architect and fits with other things the architect is considering at that time. Design is seen as a problem-solving process of searching through a space of design solutions. The process of finding a solution to a design problem involves, identifying one or more objectives, making design decisions based on the objectives, predicting and evaluating the performance to find the acceptable decisions. Each of these activities can be performed inside or outside the formal model. In designing a roof, an architect or building designer has to make many decisions on the materials. The arrangement of these materials determines the aesthetic appearance of the roof and the house. Other considerations that affect the choice of roofing materials are thermal performance, rain, fire protection, cost, availability and maintenance. Recyclability of materials, hazardous materials, life-cycle expectancy, solutions, and design options as they relate to the environment also need to be considered. Consequently, the design of roof has become quite a complex and multifaceted problem. The principal need is for a direct design aid which can generate feasible solutions and tradeoff performance in conflicting requirements and prescribe the optimum solution. This paper presents a conceptual Computer Aided Design model for dwelling roof. It is based on generation and optimization paradigms of Computer Aided Design, which is diametrically opposite to conventional simulation. The design of roof (design goal) can be defined in terms of design objective as "control radiant and conduction heat." This objective must be satisfied to achieve the design goal. The performance variables, such as roof ceiling surface temperature or new thermal performance index (TPI*) must acquire values within certain ranges which will satisfy the objective. Given the required inputs, this computer model automatically generates prescriptive quantitative information to design roof to achieve optimum thermal comfort in warm humid tropics. The model first generates feasible solutions based on the decision rules, next it evaluates the thermal performance of the roof taking into account design variables related to the building's roof and finally it applies numerical optimization techniques to automatically determine the optimum design variables, which achieve the best thermal performance. The rational and methodology used to develop the proposed model is outlined and the implementation of model is described with examples for climatic and technological contexts of India and Australia. 
Herssens, Jasmien, and Heylighen Ann. "A Framework of Haptic Design Parameters for Architects: Sensory Paradox Between Content and Representation ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 685-700. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Architects like other designers tend to think, know and work in a visual way. In design research, this way of knowing and working is highly valued as paramount to design expertise (Cross 1982, 2006). In case of architecture, however, it is not only a particular strength, but may as well be regarded as a serious weakness. The absence of non-visual features in traditional architectural spatial representations indicates how these are disregarded as important elements in conceiving space (Dischinger 2006). This bias towards vision, and the suppression of other senses in the way architecture is conceived, taught and critiqued results in a disappearance of sensory qualities (Pallasmaa 2005). Nevertheless, if architects design with more attention to non visual senses, they are able to contribute to more inclusive environments. Indeed if an environment offers a range of sensory triggers, people with different sensory capacities are able to navigate and enjoy it. Rather than implementing as many sensory triggers as possible, the intention is to make buildings and spaces accessible and enjoyable for more people, in line with the objective of inclusive design (Clarkson et al. 2007), also called Design for All or Universal Design (Ostroff 2001). Within this overall objective, the aim of our study is to develop haptic design parameters that support architects during design in paying more attention to the role of haptics, i.e. the sense of touch, in the built environment by informing them about the haptic implications of their design decisions. In the context of our study, haptic design parameters are defined as variables that can be decided upon by designers throughout the design process, and the value of which determines the haptic characteristics of the resulting design. These characteristics are based on the expertise of people who are congenitally blind, as they are more attentive to non visual information, and of professional caregivers working with them. The parameters do not intend to be prescriptive, nor to impose a particular method. Instead they seek to facilitate a more inclusive design attitude by informing designers and helping them to think differently. As the insights from the empirical studies with people born blind and caregivers have been reported elsewhere (Authors 2010), this paper starts by outlining the haptic design parameters resulting from them. Following the classification of haptics into active, dynamic and passive touch, the built environment unfolds into surfaces that can act as movement, guiding and/or rest plane. Furthermore design techniques are suggested to check the haptic qualities during the design process. Subsequently, the paper reports on a focus group interview/workshop with professional architects to assess the usability of the haptic design parameters for design practice. The architects were then asked to try out the parameters in the context of a concrete design project. The reactions suggest that the participating architects immediately picked up the underlying idea of the parameters, and recognized their relevance in relation to the design project at stake, but that their representation confronts us with a sensory paradox: although the parameters question the impact of the visual in architectural design, they are meant to be used by designers, who are used to think, know and work in a visual way. 
Sokmenoglu, Ahu, Cagdas Gulen, and Sevil Sariyildiz. "A Multi-dimensional Exploration of Urban Attributes by Data Mining." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 333-350. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The paper which is proposed here will introduce an ongoing research project aiming to research data mining as a methodology of knowledge discovery in urban feature analysis. To address the increasing multi-dimensional and relational complexity of urban environments requires a multidisciplinary approach to urban analysis. This research is an attempt to establish a link between knowledge discovery methodologies and automated urban feature analysis. Therefore, in the scope of this research we apply data mining methodologies for urban analysis. Data mining is defined as to extract important patterns and trends from raw data (Witten and Frank, 2005). When applied to discover relationships between urban attributes, data mining can constitute a methodology for the analysis of multi-dimensional relational complexity of urban environments (Gil, Montenegro, Beirao and Duarte, 2009) The theoretical motivation of the research is derived by the lack of explanatory urban knowledge which is an issue since 1970´s in the area of urban research. This situation is mostly associated with deductive methods of analysis. The analysis of urban system from the perspective of few interrelated factors, without considering the multi-dimensionality of the system in a deductive fashion was not been explanatory enough. (Jacobs, 1961, Lefebvre, 1970 Harvey, 1973) To address the multi-dimensional and relational complexity of urban environments requires the consideration of diverse spatial, social, economic, cultural, morphological, environmental, political etc. features of urban entities. The main claim is that, in urban analysis, there is a need to advance from traditional one dimensional (Marshall, 2004) description and classification of urban forms (e.g. Land-use maps, Density maps) to the consideration of the simultaneous multi-dimensionality of urban systems. For this purpose, this research proposes a methodology consisting of the application of data mining as a knowledge discovery method into a GIS based conceptual urban database built out of official real data of Beyoglu. Generally, the proposed methodology is a framework for representing and analyzing urban entities represented as objects with properties (attributes). It concerns the formulation of an urban entity´s database based on both available and non-available (constructed from available data) data, and then data mining of spatial and non-spatial attributes of the urban entities. Location or position is the primary reference basis for the data that is describing urban entities. Urban entities are, building floors, buildings, building blocks, streets, geographically defined districts and neighborhoods etc. Urban attributes are district properties of locations (such as land-use, land value, slope, view and so forth) that change from one location to another. Every basic urban entity is unique in terms of its attributes. All the available qualitative and quantitative attributes that is relavant (in the mind of the analyst) and appropriate for encoding, can be coded inside the computer representation of the basic urban entity. Our methodology is applied by using the real and official, the most complex, complete and up-to-dataset of Beyoglu (a historical neighborhood of Istanbul) that is provided by the Istanbul Metropolitan Municipality (IBB). Basically, in our research, data mining in the context of urban data is introduced as a computer based, data-driven, context-specific approach for supporting analysis of urban systems without relying on any existing theories. Data mining in the context of urban data,  Can help in the design process by providing site-specific insight through deeper understanding of urban data.  Can produce results that can assist architects and urban planners at design, policy and strategy levels. Can constitute a robust scientific base for rule definition in urban simulation applications such as urban growth prediction systems, land-use simulation models etc. In the paper, firstly we will present the framework of our research with an emphasis on its theoretical background. Afterwards we will introduce our methodology in detail and finally we will present some of important results of data mining analysis processed in Rapid Miner open-source software. Specifically, our research define a general framework for knowledge discovery in urban feature analysis and enable the usage of GIS and data mining as complementary applications in urban feature analysis. Acknowledgments I would like to thank to Nuffic, the Netherlands Organization for International Cooperation in Higher Education, for funding of this research. I would like to thank Ceyhun Burak Akgul for his support in Data Mining and to H. Serdar Kaya for his support in GIS. 
Cóté, Pierre, Mohamed-Ahmed Ashraf, and Tremblay Sebastien. "A Quantitative Method to Compare the Impact of Design Mediums on the Architectural Ideation Process." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 539-556. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. If we compare the architectural design process to a black box system, we can assume that we now know quite well both inputs and outputs of the system. Indeed, everything about the early project either feasibility studies, programming, context integration, site analysis (urban, rural or natural), as well as the integration of participants in a collaborative process can all be considered to initiate and sustain the architectural design and ideation process. Similarly, outputs from that process are also, and to some extent, well known and identifiable. We are referring here, among others, to the project representations or even to the concrete building construction and its post-evaluation. But what about the black box itself that produces the ideation. This is the question that attempts to answer the research. Currently, very few research works linger to identify how the human brain accomplishes those tasks, how to identify the cognitive functions that are playing this role, to what extent they operate and complement each other, and among other things, whether there possibly a chain of causality between these functions. Therefore, this study proposes to define a model that reflects the activity of the black box based on the cognitive activity of the human brain. From an extensive literature review, two cognitive functions have been identified and are investigated to account for some of the complex cognitive activity that occurs during a design process, namely the mental workload and mental imagery. These two variables are measured quantitatively in the context of real design task. Essentially, the mental load is measured using a Bakan's test and the mental imagery with eyes tracking. The statistical software G-Power was used to identify the necessary subject number to obtain for significant variance and correlation result analysis. Thus, in the context of an exploratory research, to ensure effective sample of 0.25 and a statistical power of 0.80, 32 participants are needed. All these participants are students from 3rd, 4th or 5th grade in architecture. They are also very familiar with the architectural design process and the design mediums used, i.e., analog model, freehand drawing and CAD software, SketchUp. In three experimental sessions, participants were asked to design three different projects, namely, a bus shelter, a recycling station and a public toilet. These projects were selected and defined for their complexity similarity, taking into account the available time of 22 minutes, using all three mediums of design, and this in a randomly manner to avoid the order effect. To analyze the two cognitive functions (mental load and mental imagery), two instruments are used. Mental imagery is measured using eye movement tracking with monitoring and quantitative analysis of scan paths and the resulting number and duration of participant eye fixations (Johansson et al, 2005). The mental workload is measured using the performance of a modality hearing secondary task inspired by Bakan'sworks (Bakan et al., 1963). Each of these three experimental sessions, lasting 90 minutes, was composed of two phases: 1. After calibrating the glasses for eye movement, the subject had to exercise freely for 3 minutes while wearing the glasses and headphones (Bakan task) to get use to the wearing hardware. Then, after reading the guidelines and criteria for the design project (± 5 minutes), he had 22 minutes to execute the design task on a drawing table allowing an upright posture. Once the task is completed, the subject had to take the NASA TLX Test, on the assessment of mental load (± 5 minutes) and a written post-experimental questionnaire on his impressions of the experiment (± 10 minutes). 2. After a break of 5-10 minutes, the participant answered a psychometric test, which is different for each session. These tests (± 20 minutes) are administered in the same order to each participant. Thus, in the first experimental session, the subject had to take the psychometric test from Ekstrom et al. (1978), on spatial performance (Factor-Referenced Cognitive Tests Kit). During the second session, the cognitive style is evaluated using Oltman's test (1971). Finally, in the third and final session, participant creativity is evaluated using Delis-Kaplan test (D-KEFS), Delis et al. (2001). Thus, this study will present the first results of quantitative measures to establish and validate the proposed model. Furthermore, the paper will also discuss the relevance of the proposed approach, considering that currently teaching of ideation in ours schools of architecture in North America is essentially done in a holistic manner through the architectural project. 
Zahedi, Mithra, Guité Manon, and De Giovanni. "Addressing User-Centeredness: Communicating Meaningfully Through Design ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 513-524. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The construction industry is one that is fragmented by nature. In current practice, information is exchanged between the designers and contractors in the form of paper documents such as drawings, bills of material and specifications. Information is lost and errors are made during the forward and backward exchange of the design-construction information and constructability knowledge between the design professionals, cost estimators and contractors. Despite the technological developments in IT, the industry has been slow in adopting change in its processes. Computer Integrated Construction (CIC) strives to bridge the gaps of information by integrating the tools and processes within the Architecture, Engineering and Construction industries. This thesis proposes an integrated methodology across the design and construction functions supported by available CAD technologies. The proposed methodology has been implemented in a prototype software application named &ldquo,CAD-B PM&rdquo, that allows the user to integrate the CAD design with a central database that is a repository of project information. Productivity and cost estimates are generated within the database and are further integrated to a scheduling application for project planning and control. The prototype system provides a unique solution where the project information is openly shared between the applications in a dynamic environment through the use of Open Database Connectivity (ODBC). 
Plume, Jim, and Mitchell John. "An Urban Information Framework to support Planning, Decision-Making and Urban Design." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 653-668. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. This paper reports on a 2-year research project undertaken in collaboration with a state planning authority, a major city municipal council and a government-owned development organisation. The project has involved the design of an urban information model framework with the aim of supporting more informed urban planning by addressing the intersection where an individual building interfaces with its urban context. This adopted approach enables new techniques that better model the city and its processes in a transparent and accessible manner. The primary driver for this project was the challenge provided by the essential incompatibility between legacy GIS (geographic information system) datasets and BIM (building information model) representations of the built form. When dealing with urban scale information, GIS technologies use an overlay mapping metaphor linked to traditional relational database technologies to identify features or regions in the urban landscape and attach attribute data to those in order to permit analysis and informed assessment of the urban form. On the other hand, BIM technologies adopt an object-oriented approach to model the full three-dimensional characteristics of built forms in a way that captures both the geometric and physical attributes of the parts that make up a building, as well as the relationships between those parts and the spaces defined by the building fabric. The latter provides a far richer semantic structure to the data, while the former provides robust tools for a wide range of urban analyses. Both approaches are widely recognised as serving well the needs of their respective domains, but there is a widespread belief that we need to reconcile the two disparate approaches to modelling the real world. This project has sought to address that disjunction between modelling approaches. The UrbanIT project concentrated on two aspects of this issue: the development of a framework for managing information at the precinct and building level through the adoption of an object-oriented database technology that provides a platform for information management, and an exploration of ontology tools and how they can be adopted to facilitate semantic information queries across diverse data sources based on a common urban ontology. This paper is focussed on the first of those two agendas, examining the context of the work, the challenges addressed by the framework and the structure of our solution. A prototype implementation of the framework is illustrated through an urban precinct currently undergoing renewal and redevelopment, finishing with a discussion of future work that comes out of this project. Our approach to the implementation of the urban information model has been to propose extensions to ISO/PAS 16739, the international standard for modelling building information that is commonly known as IFC (Industry Foundation Classes). Our reason for adopting that approach is primarily our deep commitment to the adoption of open standards to facilitate the exchange of information across the built environment professions, but also because IFC is based on a robust object schema that can be used to construct a internet-accessible database able, theoretically, to handle the vast quantity of data needed to model urban-scale information. The database solution comes with well-established protocols for handling data security, integrity, versioning and transaction processing or querying. A central issue addressed through this work is concerned with level of detail. An urban information model permits a very precise and detailed representation of an urban precinct, while many planning analyses rely on simplified object representations. We will show that a key benefit of our approach is the ability to simultaneously maintain multiple representations of objects, making use of the concept of model view definitions to manage diverse analysis needs. 
Chung, Daniel, Chye Heng, Lai Lee, and Ji Zhang. "Analyzing the Ventilation Performance of Tropical High Density Residential Precincts using Computational Fluid Dynamics." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 351-366. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Major cities in the world are getting bigger as they continue to grow to cater for more population increase. These cities normally forced the urban planning to go high density. In the tropical context, high density cities like Singapore and Hong Kong do not have the luxury of space to go low rise and compact. These cities have to build to the floor area ratio of 4 and above to cater for the population. Their only solution is to go up, as high as possible, to the extent that the natural wind flow pattern will be altered, which brings environmental impact to the people. This is generally not good since wind flow helps to maintain the thermal comfort of the people as heat and pollutants are being channeled out of the city to avoid Urban Heat Island effect. In the tropical context, wind flow is crucial to maintain people's comfort as the temperature is generally very high from the exposure of the sun for the entire year. Studies have shown that wind flow plays the most significant part in maintaining human comfort despite exposing to direct sunlight in the tropics. Therefore, wind flow analysis is extremely crucial to make the design sustainable and energy efficient, as people will not have to depend on mechanical ventilation to compensate for the lack of wind flow. Computational Fluid Dynamics (CFD) has always been used in the field of architecture, urban design and urban planning to understand the patterns of wind flow through the built environment apart from wind tunnel tests. The availability of more powerful hardware for the mainstream computer users as well as the lowering costs of these computers made CFD more possible to be adopted in the design world today. This also means using CFD in the design process, especially to analyze the impact of the design to the current site conditions and annual wind patterns will help the new design to be more responsive to the site. The interest of this paper is to analyze the high density typologies to see how well they respond to the local wind flow pattern. A typology is considered acceptable when the wind flow going through the site is still maintaining acceptable wind speed. This means it does not block off the wind and create stagnant spaces. Different designs generate different typologies which will respond differently to the wind pattern. The study aims at comparing the local high density typologies in terms of their response to the wind. Changes to a typology can be explored too to see if the performance will be different. For a typology which is considered a total failure in terms of response to wind, it may improve its performance if the orientation is altered. The CFD software can also parametrically respond to the changes of the typologies dimensions. This is helpful to see how much more a typology can still be performing well before failure by increasing the floor area index. The easiest way to do this is to pump up the building height. In conclusion, designing in response to wind is extremely important as it is more sustainable and responsive to Urban Heat Island effect. A design which responds well to the wind patterns will help save cost of cooling load and fan expenditure. The people will also be more willing to use the outdoor spaces which will as a whole generate more vibrant city spaces. As a result, a high density city with huge population count can still enjoy good thermal comfort if the general urban planning and design respond well to wind. 
Haeusler, Matthias, and Beilharz Kirsty. "Architecture = Computer, from Computational to Computing Environments." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 217-232. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Drawing on architecture, urban digital media, engineering, IT and interaction design, the research presented in this paper outlines a possible shift from architecture designed through computation (any type of process, algorithm or measurement done in a computational matter) towards architecture capable of computing (developing, using and improving computer technology, computer hardware and software as a space-defining element). The research is driven by recent developments in four fields, as follows: (a) Architecture in its recent development has shifted from a planar box, as was the ideal in the modernist movement, towards complex and non-standard forms. (b) The design concepts of non-standard surfaces have been adopted into media facades and media architecture by liberating the pixel from its planar position on a screen [1]. (c) Advancements in pervasive computing applications are now able both to receive information from the environment in which they are used and to detect other devices that enter this environment [2]. (d) Developments in advanced autonomous systems such as Human Computer Interaction (HCI) or Human Robot Interaction (HRI), have produced intelligent systems capable of observing human cues and using these cues as the basis for intelligent decision-making [3]. Media fa_?ade developments work in the direction of the above-mentioned four fields, but often come with limitations in architectural integration, they need additional components to interact with their environment and their interactions are both often limited to visual interactions and require the user to act first. The researched system, Polymedia Pixel [4] discussed in this paper, can overcome these limitations and fulfil the need for a space-defining material capable of computing, thus enabling a shift from architecture designed by computation towards architecture capable of active computing. The Polymedia Pixel architecture merges digital technology with ubiquitous computing. This allows the built environment and its relation with digital technology to develop from (a) architecture being represented by computer to (b) computation being used to develop architecture and then further to where (c) architecture and the space-defining objects have computing attributes. Hence the study presented aims to consider and answer this key question: When building components with computing capacity can define space and function as a computer at the same time, what are the constraints for the building components and what are the possible advantages for the built environment?´ The conceptual framework, design and methods used in this research combine three fields: (a) hardware (architecture and design, electronic engineering) (b) software (content design and IT) and (c) interaction design (HCI and HRI). Architecture and urban design determinates the field of application. Media architecture and computer science provide the technological foundation, while the field of interaction design defines the methodology to link space and computing [5]. The conceptual starting point is to rethink the application of computers in architecture and, if architecture is capable of computing, what kind of methodology and structure would find an answer to the above core research question, and what are the implications of the question itself? The case study discusses opportunities for applying the Polymedia Pixel as an architectural component by testing it on: (a) constraint testing applying computational design methodologies to design space (b) singular testing - discussing the advantages for an individual building, and (c) plural testing investigating the potential for an urban context. The research aims to contribute to the field of knowledge through presenting first steps of a System System mode where buildings can possibly watch and monitor each other, additional to the four primary interactive modes of operation. This investigation, its proposed hypothesis, methodology, implications, significance and evaluation are presented in the paper. 
Sherif, A., L Jinkook, and E Chuck. "Automated Cost Analysis of Concept Design BIM Models." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 403-418. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. AUTOMATED COST ANALYSIS OF CONCEPT DESIGN BIM MODELS Interoperability: BIM models and cost models This paper introduces the automated cost analysis developed for the General Services Administration (GSA) and the analysis results of a case study involving a concept design courthouse BIM model. The purpose of this study is to investigate interoperability issues related to integrating design and analysis tools, specifically BIM models and cost models. Previous efforts to generate cost estimates from BIM models have focused on developing two necessary but disjoint processes: 1) extracting accurate quantity take off data from BIM models, and 2) manipulating cost analysis results to provide informative feedback. Some recent efforts involve developing detailed definitions, enhanced IFC-based formats and in-house standards for assemblies that encompass building models (e.g. US Corps of Engineers). Some commercial applications enhance the level of detail associated to BIM objects with assembly descriptions to produce lightweight BIM models that can be used by different applications for various purposes (e.g. Autodesk for design review, Navisworks for scheduling, Innovaya for visual estimating, etc.). This study suggests the integration of design and analysis tools by means of managing all building data in one shared repository accessible to multiple domains in the AEC industry (Eastman, 1999, Eastman et al., 2008, authors, 2010). Our approach aims at providing an integrated platform that incorporates a quantity take off extraction method from IFC models, a cost analysis model, and a comprehensive cost reporting scheme, using the Solibri Model Checker (SMC) development environment. Approach As part of the effort to improve the performance of federal buildings, GSA evaluates concept design alternatives based on their compliance with specific requirements, including cost analysis. Two basic challenges emerge in the process of automating cost analysis for BIM models: 1) At this early concept design stage, only minimal information is available to produce a reliable analysis, such as space names and areas, and building gross area, 2) design alternatives share a lot of programmatic requirements such as location, functional spaces and other data. It is thus crucial to integrate other factors that contribute to substantial cost differences such as perimeter, and exterior wall and roof areas. These are extracted from BIM models using IFC data and input through XML into the Parametric Cost Engineering System (PACES, 2010) software to generate cost analysis reports. PACES uses this limited dataset at a conceptual stage and RSMeans (2010) data to infer cost assemblies at different levels of detail. Functionalities Cost model import module The cost model import module has three main functionalities: generating the input dataset necessary for the cost model, performing a semantic mapping between building type specific names and name aggregation structures in PACES known as functional space areas (FSAs), and managing cost data external to the BIM model, such as location and construction duration. The module computes building data such as footprint, gross area, perimeter, external wall and roof area and building space areas. This data is generated through SMC in the form of an XML file and imported into PACES. Reporting module The reporting module uses the cost report generated by PACES to develop a comprehensive report in the form of an excel spreadsheet. This report consists of a systems-elemental estimate that shows the main systems of the building in terms of UniFormat categories, escalation, markups, overhead and conditions, a UniFormat Level III report, and a cost breakdown that provides a summary of material, equipment, labor and total costs. Building parameters are integrated in the report to provide insight on the variations among design alternatives. 
Tidafi, Temy, Charbonneau Nathalie, and Khalili-Araghi Salman. "Backtracking Decisions within a Design Process: a Way of Enhancing the Designer's Thought Process and Creativity." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 573-587. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. This paper proposes a way computer sciences could contribute to stimulate the designer's reflexive thought. We explore the possibility of making use of backtracking devices in order to formalize the designer's thought process. Design, as a process of creating an object, cannot be represented by means of a linear timeline. Accordingly, the backtracking processes we are discussing here are not based on a linear model but rather on a non-linear structure. Beyond the notion of undoing and redoing commands within CAD packages, the backtracking process is seen as a way to explore and record several alternate options. The branches of the non-linear model can be seen as pathways made of sequential decisions. The designer creates and explores these pathways while making tentative moves towards an architectural solution. Within the design process, backtracking enables the designer to establish and act on a network of interrelated decisions. This notion is fundamental. It is quite obvious that information, in order to be meaningful, must occupy a specific place within an informational network. A data, separated from its context, is devoid of interest. By the same token, a decision takes on significance solely in combination with other decisions. In this paper, we examine what kinds of decisions are involved within a design process, how they are connected, and what could be the best ways to formalize the relationships. Our goal is to experiment ways that could enable the designer and his/her collaborators to get a clearer mental picture of the network of decisions aforementioned. The non-linear model can be seen as a graph structure. The user moves wherever he/she wants through the branches of the structure to establish the network of decisions or to get reacquainted with a previous design process. As a matter of fact, it can act in both ways: to reassess or to confirm a decision. On the one hand, the designer can go back to previous states, reconsider past choices, and eventually modify them. On the other hand, he/she can move forward and revisit a given sequence of decisions, so as to recapture the essence of a previous design process. It goes without saying that knowledge regarding the design process is constructed by the designer from his/her own experiences. Since the designer´s perception evolves as time goes by, the network of decisions constitutes a model that is continuously questioned and restructured. The designer does not elaborate solely an architectural object, but also an evolving model formalizing the way he/she achieved his/her aim. As Le Moigne (1995) pointed out, the model itself produces knowledge, afterwards, the designer can examine it so as to get a clearer mental picture of his/her own cognitive processes. Furthermore, it can be used by his/her collaborators in order to understand which thread of ideas led the designer to a given visual result, and eventually resume or reorient the design process. In addition to reflecting on the ideological implications inherent to this questioning, we take into account the feasibility of such a research project. From a more technical point of view, in this paper we will describe how we plane to take up the challenge of elaborating a digital environment enabling backtracking processes within graph structures. Furthermore, we will explain how we plane to test the first trial version of the new environment with potential users so as to observe how they respond to it. These experiments will be conducted in order to verify to what extend the methods we are proposing are able to i) enhance the designer´s creativity and ii) increase our understanding of designer´s thought process. 
Veliz, Alejandro, Medjdoub Benachir, and Kocaturk Tuba. "Bridging the Gap in Constraint-Based Design ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 133-148. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Mass customization is one of the most promising computational developments in the AEC industry. Despite recent advances in the production of research-based knowledge, the professional practices lack of a consistent and permanent technology adoption scheme and remain as a very resilient and fragmented industry. This work is a part of an ongoing research project developing guidelines for improving both physical and virtual modeling processes within an architectural design context. Here, we present a customizable model of a space layout explorer. The implementation of the user-driven solution-finding process is based on constraint technology embedded in Autodesk's Revité 2011 macros tools, commonly used in the professional practice. The aim of this work is to demonstrate a practical use of a small constraint-based system on software of widespread use. Even though there is still a lack of building information, the model has already several applications in the definition a floor plan layout and in the comparison of several instances of the design solution in the 3D user view. User-driven modifications are not made directly through the 3D model, but through different explicit text tags that describe each parameter on 2D views -although a real time 3D visualization of the model is also available-. The main findings are discussed as guidelines for further research on the end-user involvement on a “creative mass customization” scheme. Also, the implementation of visual aids such as text tags during the customization process can bridge some technical obstacles for the development of interfaces for constraint-based mass customization systems. Before the final discussion, some limitations on the use of this model are described.
Nasirova, Diliara, Erhan Halil, Andy Huang, Robert F. Woodbury, and Bernhard Riecke. "Change Detection in 3D Parametric Systems: Human-Centered Interfaces for Change Visualization." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 751-764. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The research on current parametric modeling systems concerns mainly about the underlying computational technology and designs produced, and emphasizes less human factors and design tasks. We observe users being challenged in interacting with these systems regardless of their expertise level. In these systems, user's attention is divided on system-imposed actions such as tool selection and set-up, managing obscured views, frequent view manipulation, and switching between different types of representations. In essence, control of the system can become more demanding than the design task itself. We argue that this unbalanced emphasis inhibits one of the most important functions of parametric design: agility in exploration of design alternatives by applying frequent user-introduced or system-generated changes on the parametric design models. This compounded by the effect of cognitive limitations such as change blindness and shifts in locus of attention hinders change control and imposes an extra cognitive load in design. In this paper, we made a first step in developing a set of heuristics that is going to present how designers change control and detection can be improved. We experimented with three interfaces that control and visualize changes on three different compositions in relation to the designer's locus of attention: on-model, peripheral and combined views. We measured designers performance as the number of changes detected, number of trials, and time required to complete each change detection task. The results support our hypothesis that change blindness significantly slows down and overloads design thinking, and thus should not be ignored. Furthermore, an interesting finding shows that visualizations on the visual periphery can equally support change detection as on-model visualizations, but it is significantly easier and faster to detect changes when they are visualized in both views. These findings can guide us to develop better interfaces in 3D parametric systems.
Huang, Andy, Erhan Halil, Robert F. Woodbury, Nasirova Diliara, and Kozlova Karine. "Collaboration Workflow Simplified: Reduction of Device Overhead for Integrated Design Collaboration." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 591-602. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Design collaboration relies on cognitive tools such as analog media and digital peripheral devices, and shows the characteristics of distributed cognition. It is a social and complex activity involving multiple agents communicating and using external cognitive tools to encode, decode, and share information in the process of collaborative task completion. The systems supporting this activity should meet the “principle of least collaboration effort” [4] that proposes that agents in collaboration minimize their effort in presentation and acceptance of information. Yet, current collaboration systems are dispersed mixed media that is often overloaded with representations and functionality, thus preventing seam- less information sharing. Designers are required to spend extra effort collecting information using peripheral devices and in system management when sharing information. The goal of this study is to understand these overheads in infor- mation collection and sharing using peripheral devices, and to provide designers with a supportive platform to enhance collaboration using both analog and digital media. In this paper, we first review available peripheral devices such as smart pens, digital cameras, and voice recorders, as well as existing collaboration sup- porting software systems for their benefits and deficiencies in collaboration. We then present “DiNa”, a collaboration platform that is envisioned to improve pro- ductivity and reduce redundant work by integrating peripheral devices into the collaboration workflow. We demonstrate a possible workflow using this system through several scenarios where designers collaborate in performing a series of design tasks. We hope to bring attention to the importance least collaborative effort in designing systems to support real-world collaboration.
Hsiao, Chih-Pin, and Brian Johnson. "Combined Digital and Physical Modeling with Vision-Based Tangible User Interfaces: Opportunities and Challenges." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 785-800. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Designers in architectural studios, both in education and practice, have worked to integrate digital and physical media ever since they began to utilize digital tools in the design process. There are benefits of working in the digital domain as well as benefits of working physically, confronting, or seeming to confront, architects with a difficult choice. Emerging strategies for human-computer interaction such as tangible user interfaces and computer vision techniques present new possibilities for manipulating architectural designs. These technologies can help bridge between the digital and physical worlds. This paper discusses some of these technologies, analyzes several current design challenges and presents a prototype that illustrates ways in which a broader approach to human- computer interaction might resolve the problem. The ultimate goal of breaking down the boundary between the digital and physical design platforms is to create a unified domain of "continuous thought" for all design activities.
Dorta, Tomás, Yehuda Kalay, Lesage Annemarie, and Perez Edgar. "Comparing Immersion in Remote and Local Collaborative Ideation Through Sketches: a Case Study." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 25-40. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Sketches are used in design to support ideation, communication, and collaboration because of their intuitiveness, abstraction, ambiguity and inaccuracy. Design collaboration using freehand sketches is possible through whiteboard software on the Internet. Designers can co-design and share design referents through these tools while adding gestures and expressions using web cams. Freehand sketching using whiteboard software retains the same proportion and scale problems as traditional sketching on paper, but adds digital behaviour (pen tablet display, undo, etc.) and the ability to share sketches in real time with a remote design team. Still, designers are not immersed in their representations. Moreover, such representations can include errors because designers work without reference to real-life perspective views. We developed a system, called the Hybrid Ideation Space (HIS) that allows designers to be immersed in their freehand sketches. The system supports local and remote collaboration, allowing designers to be literally inside their life sized, real time representations, while sharing them with remote collaborators who use another HIS. This paper presents a case study comparing the HIS to conventional whiteboard software (Vyew™) in a context of local and remote design collaboration on two landscape architecture projects. Two multidisciplinary teams worked on the first steps of two ad-hoc projects. The goal was to make an initial observation of the impact of immersion and see if it delivers benefits to collaborative ideation. Two methodological tools supported the study: the Design Flow for the experience that includes the NASA TLX to measure the workload, and the Collaborative Ideation Loop (CI-Loop) for design collaboration. 
Shadkhou, Shaghayegh, and Jean-Claude Bignon. "Cooperative Design to Construction: a sharable Model for Non-Standard Timber Construction." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 603-618. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Abstract Architectural design is confronted to a renewal of formal vocabulary regarding the advancements on computational techniques. Non-standard architecture demands a hybrid approach regarding design and construction. It revives common borders between architectural and technical design. However, the respective digital assistance is confronted to discontinuity. This paper reports on part of a research activity aiming at elaborating a sharable model which by integrating construction knowledge assists the emergence of constructible geometry for timber construction.   
Iordanova, Ivanka, Forgues Daniel, and Chiocchio François. "Creation of an Evolutive Conceptual Know-how Framework for Integrative Building Design." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 435-450. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Low productivity of the building sector today is attributed to the fragmentation of tasks, disciplines and responsibilities, as well as to the resistance to adopt integrative work processes and digital means. The increased complexity of architectural projects and the aroused social consciousness for sustainable environment calls for integrative design collaboration. Thus, there is need for a Conceptual Framework combining work processes, technological means and policy aspects. According to the literature, integrative multidisciplinary design is a strategy resulting in high performance buildings nurturing sustainable way of living (Reed et al. 2009, Krygiel & Nies 2008). Responding to the increased technological complexity of our built environment, as well as to the objective of meeting multiple criteria of quality, both necessitating multidisciplinary collaboration during design, Building Information Modeling (BIM) is seen as a powerful means for fostering quality, augmenting productivity and decreasing loss in construction. Based on recent research, we can propose that a sustainable building can be designed through an integrative design process (IDP) which is best supported by BIM. However, our ongoing research program and consultations with advanced practitioners underscore a number of limitations. For example, a large portion of the interviewed professionals and construction stakeholders do not necessarily see a link between sustainable building, integrative design process and BIM, while in our opinion, their joint use augments the power of each of these approaches taken separately. Thus, there is an urgent necessity for the definition of an IDP-BIM framework, which could guide the building industry to sustainable results and better productivity. This paper defines such a framework, whose theoretical background lays on studies in social learning (activity theory and situated action theories). These theories suggest that learning and knowledge generation occurs mainly within a social process defined as an activity. This corresponds to the context in which the IDP-BIM framework will be used, its final objective being the transformation of building design practices. The proposed IDP-BIM framework is based on previous research and developments. Thus, firstly, IDP process was well formalized in the Roadmap for the Integrated Design Process (Reed et al.) which is widely used as a guideline for collaborative integrative design by innovating practices in USA and Canada. Secondly, the National Building Information Modeling Standard (NBIMS) of the USA is putting an enormous effort in creating a BIM standard, Succar (2008) recently proposed a conceptual framework for BIM, but BIM ontology is still under development (Gursel et al 2009). Thirdly, an iterative design process bound to gating reviews (inspired from software development processes) was found to be successful in the context of multidisciplinary design studios (reported in our previous papers). The feedback from this study allowed for modifications and adjustments included in the present proposal. The gating process assures the good quality of the project and its compliance to the client's requirements. The challenge of this research is to map the above mentioned approaches, processes and technologies into the design process, thus creating an integrated framework supporting and nurturing sustainable design. The IDP-BIM framework can be represented by a multidimensional matrix linked to a semantic network knowledge database: - the axes of the matrix being the project timeline, the design process actors and building stakeholders (architect, engineers, client, contractor, environmental biologist, etc.), or different aspects of building performance (environmental, functional, social, interior environment quality, cost, etc.), and - the knowledge database providing multiple layers of semantic support in terms of process, domain knowledge, technology and workflow at a given moment of the project and for a given actor or building aspect. The IDP-BIM framework is created as an evolutive digital environment for know-how and will have an established protocol for regular updates. The paper will firstly present the state of the art in IDP and BIM. Secondly, it will expose the methodology used for the definition of the Framework, followed by a description of its structure, contents and digital implementation. Then, some scenarios for the use of the Framework will be shown as validation.
Shin, Dongyoun, Muller Stefan, and Gerhard Schmitt. "Crowdsourcing Urban Simulation Platform Using Mobile Devices and Social Networking Media Technologies." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 233-246. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Introduction and Research Questions The research area of urban simulation methods has grown notably in recent decades. Most of the research topics that concern urban simulation have concentrated on defining the complexities of urban environments with certain rules and algorithms. However, cities are getting more complex and changes to them are being made at greater speed. Therefore, current urban simulation modeling approaches based on rules and protocols are still struggling to reduce the gap between the virtual simulation environment and the real cities, since the behavior of citizens is frequently unpredictable and continuously adapting. In this context, research is necessary to develop more fundamental simulation methods that can handle these complexities and changes, leading to new design decision support systems. Therefore, this research was motivated with the following questions: What is the origin of the complexities and transformations of the urban environment? How can we approach the origin to deal with the urban complexities and transformations? To answer these questions, we hypothesize that the diverse human intentions are the origin of the issues that result from all of the complexities and changes of the cities. General Objectives As a result, we propose a participatory simulation environment that brings human intention into the urban simulator: a crowdsourcing [1] simulation platform that is operated by the people's participation. To achieve this crowdsourcing urban sustainability simulation environment, we must address the following research issues: categorization of urban sustainability indicators and technologies, inducing mass participations, and an implementation of social network services. Furthermore, we aim at using mobile computing devices, such as smart phones, as a terminal to the simulation environment. Fundamental Goals Our goal is to enable people to share urban information at any time and to compare each other's contributions through the crowdsourcing urban simulation platform. The information will be returned to the citizens to support their sustainability-aware life. The simulation platform also gives a chance not only to compare each other's levels of sustainability, but also to give self-satisfaction through an altruistic contribution for a sustainable future. Thus, people shall utilize the simulator in order to predict their individual or cities's future sustainability. Meanwhile, the user data will be collected and delivered to the central server in order to analyze the urban sustainability. Consequently, we can measure the urban sustainability based on a real human interaction, and compare individuals as well as cities. The whole process of this research is presented as a new paradigm of an urban simulator that reflects the urban complexities and the inconstant human mind changes. Specific Objectives of This Paper This paper will represent strategies of the crowdsourcing urban simulation which can make a paradigm shift of urban simulation and shall define the customized sustainable indicators for the initial steps of this research. It shows how as system for can communicate with the public using the current technologies: high performance mobile media, social network services and wide-area geospatial information systems. Furthermore, for the first step of this research, the paper defines the urban sustainability indicators, and their categorization is generalized and translated into simpler ways to support the citizen's intuitive understanding. 
Verdonck, Evelien, Lieve Weytjens, Verbeeck Griet, and Froyen Hubert. "Design Support Tools in Practice. the Architects' Perspective." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 769-784. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. In recent years, a large number of design support tools (DSTs) have been developed to address the ever increasing complexity and fragmentation of the architectural design process. Despite the omnipresence and the wide variety of DSTs available to architects today, literature reveals that there is still a mismatch between existing tools and design practice. Further examination of this discrepancy might reveal possible strategies for the improvement of tools. Therefore, this study investigates the Flemish architectural practice directly through a large-scale survey including 629 architects (nearly 10% of the population). The survey was based on a practice-oriented conceptual framework, which was developed as a theoretical background for this study. First the nature of the design process was explored through extensive literature review. In addition to this, a study of tools and possible classifications was carried out. Although numerous studies are available that provide a possible classification, most focus on specific design aspects, for instance sustainability or user-centered design. However, there is no general outline of tools available that would be adequate for the purpose of this research. The DSTs included in this study range from sketches and checklists to 3D CAD and simulation software, in other words any instrument intended to support one or more aspects of the design process. The findings from both literature studies were synthesized in the conceptual framework. This framework presents the design process as a linear process, consisting of the conceptual design phase, the preliminary design phase, the building permission phase, and the construction phase. Six categories of tools were defined, according to the roles they play in the design process, namely knowledge-based, presentation, evaluation/analysis, structuring, modeling, and communication. A tool can belong to one or more categories. The mapping of these roles on the design process resulted in the final framework, which was then used as a base for the questionnaire. The survey aimed at gaining insight into the different DSTs and their corresponding roles, as well as the design phases in which they are used or most needed by Flemish architects in architectural practice. In addition to this, the survey contained questions about the influence of tools on design decision-making, and the specific characteristics and qualities the designers prefer for design support tools. A final part of the survey asked about general background information, such as the respondents age, size of architectural firm and types of projects usually undertaken. The results of the survey reveal that there are distinctly different needs for each of the roles defined, as well as a specific frequency of use within each design phase. Furthermore, the most popular tools often encompass multiple roles. Additionally, clear expectations for future tools are defined. Finally, the data collected show researchers and tool developers what kind of support designers need in the different stages of the design process, and may help them to develop DSTs accordingly, to maximize their usability and eventually contribute to decrease the gap between tools and practice.
Schneider, Sven, Braunes Joerg, Thurow Thorsten, Christian Tonn, and Koenig Reinhard. "Design Versioning - Problems and Possible Solutions for the Automatic Management of Distributed Design Processes." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 669-681. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Designing is a complex process. Where this process involves multiple participants located in different places, digital tools for supporting this process are indispensable. However, the use and creation of tools for supporting design processes necessary entails intervening in or manipulating the process it intends to support. For design collaboration tools the coordination mechanisms employed are a crucial aspect. To make these mechanisms as flexible as possible, the technical challenge lies in devising an adequate concept for storing the actions that happen during designing. This paper deals with the issue of versioning in computer-supported collaborative design environments. The paper examines the technical and conceptual problems of versioning and discusses possible solutions.
Sherif, Ahmed, and El Abbas. "Designing the Window to Fit a Shading Device, a Reversed Method for Optimizing Energy Efficient Fenestration." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 383-399. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Solar radiation passing through a window contributes significantly to cooling loads and energy consumption, especially in hot climates. Most CAAD tools handling energy efficient design help designers to define the optimal shading device to protect a window of a certain shape, usually a rectangle, but some parts of the rectangular window (such as lower corners) are typically difficult to protect. Usually the whole shading device becomes bigger to shade these corners, which over-shades the rest of the window, increasing artificial lighting and heating loads.  It also increases the complexity, visual impact and cost of the shading device.  Changing the shape of the window by cutting these corners may reduce the size of the shading device considerably, which opens way to a different or even a reversed- approach: “Designing the window to fit a shading device instead of designing the shading device to fit the window!” This approach has several potential applications. The building form itself sometimes works implicitly as a shading device. For example, if the building plan shape is a U or L shape, some parts of the walls become shaded, the windows can be placed in these shaded parts, and the window shape can be designed to fit the shadow pattern caused by the building form, changes in the building profile gives similar chances to design windows that fit the shadow pattern. Conceptually, this approach makes energy efficiency a form giving attribute, helping to create innovative facades, while giving an energy efficient configuration for both window and its shading device. CAAD tools can help the designer adopt such an innovative approach, by proposing the window shape that suits an arbitrary shading device created by the designer or a building mass. This paper examines the validity of the approach and introduces the approach required for developing a software module that can be integrated with other CAAD tools such as the Ecotect software.  This would enable the designers to use this approach. The method handles the complexity of time-dependent solar geometry and radiation intensity, the geometry of both the window and shading device, and the designers set of objectives, enabling the designer to define the required configuration of window and shading device.
Pauwels, Pieter, De Ronald, and Van Jan. "Extending the Design Process into the Knowledge of the World." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 203-216. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Research initiatives throughout history have shown how a designer typically makes associations and references to a vast amount of knowledge based on experiences to make decisions. With the increasing usage of information systems in our everyday lives, one might imagine an information system that provides designers access to the'architectural memories'of other architectural designers during the design process, in addition to their own physical architectural memory. In this paper, we discuss how the increased adoption of semantic web technologies might advance this idea. We briefly discuss how such a semantic web of building information can be set up, and how this can be linked to a wealth of information freely available in the Linked Open Data (LOD) cloud.
McMeel, Dermott. "I think Therefore i-Phone: the influence of Pervasive Media on Collaboration and Multi-Disciplinary Group Work." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 69-84. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The study of value and its transfer during the multi-disciplinary process of design is stable fodder for research, an entire issue of Design Studies has been devoted to Values in the Design Process. By scrutinising design meetings Dantec (2009) and Ball (2009) separately examine the mechanisms of value transfer between the agents involved in design (clients, designers, engineers). Dantec suggests this is best understood in terms of requirement, values and narrative, Ball proposes it should be viewed as a combination of "analogical reasoning" and "environmental simulation". If we look at Vitruvius and his primary architectural manual (Pollio 1960) we find values in the form of firmitas, utilitas and venustas embedded in this early codification of architectural practice. However, as much current research is restricted to design practice what occurs when value frameworks move between domains of cultural activity (such as design to construction and vice-versa) is not privileged with a comparably sizable body of research. This paper is concerned with the ongoing usage of pervasive media and cellular phones within communications and value transfer across the disciplinary threshold of design and construction. Through participation in a building project we analyse the subtleties of interaction between analogue communication such as sketches and digitally sponsored communication such as e-mail and mobile phone usage. Analysing the communications between the designer and builder during construction suggests it is also a creative process and the distinctions between design and construction processes are complex and often blurred. This work provides an observational basis for understanding mobile computing as a dynamic tuning´ device as hypothesized by Richard Coyne (2010) that ameliorates the brittleness of communication between different disciplines. A follow up study deploys digital field notes  (dfn) a bespoke iPhone application designed to test further suppositions regarding the influence exerted upon group working by mobile computing. Within collaboration individual communiqu's have different levels of importance depending on the specific topic of discussion and the contributing participant. This project furthers the earlier study, expanding upon what mobile computing is and enabling us to infer how these emergent devices affect collaboration. Findings from these two investigations suggest that the synchronous and asynchronous clamour of analogue and digital tools that surround design and construction are not exclusively inefficiencies or disruptions to be expunged. Observational evidence suggests they may provide contingency and continue to have value attending to the relationship between static components and the avoidance of failure within a complex system such as design and construction. 
Benros, Deborah, Granadeiro Vasco, José Duarte, and Terry Knight. "Integrated Design and Building System for the Provision of Customized Housing: the Case of Post-Earthquake Haiti." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 247-264. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The paper proposes integrated design and building systems for the provision of sustainable customized housing. It advances previous work by applying a methodology to generate these systems from vernacular precedents. The methodology is based on the use of shape grammars to derive and encode a contemporary system from the precedents. The combined set of rules can be applied to generate housing solutions tailored to specific user and site contexts. The provision of housing to shelter the population affected by the 2010 Haiti earthquake illustrates the application of the methodology. A computer implementation is currently under development in C# using the BIM platform provided by Revit. The world experiences a sharp increase in population and a strong urbanization process. These phenomena call for the development of effective means to solve the resulting housing deficit. The response of the informal sector to the problem, which relies mainly on handcrafted processes, has resulted in an increase of urban slums in many of the big cities, which lack sanitary and spatial conditions. The formal sector has produced monotonous environments based on the idea of mass production that one size fits all, which fails to meet individual and cultural needs. We propose an alternative approach in which mass customization is used to produce planed environments that possess qualities found in historical settlements. Mass customization, a new paradigm emerging due to the technological developments of the last decades, combines the economy of scale of mass production and the aesthetics and functional qualities of customization. Mass customization of housing is defined as the provision of houses that respond to the context in which they are built. The conceptual model for the mass customization of housing used departs from the idea of a housing type, which is the combined result of three systems (Habraken, 1988) -- spatial, building system, and stylistic -- and it includes a design system, a production system, and a computer system (Duarte, 2001). In previous work, this conceptual model was tested by developing a computer system for existing design and building systems (Benr__s and Duarte, 2009). The current work advances it by developing new and original design, building, and computer systems for a particular context. The urgent need to build fast in the aftermath of catastrophes quite often overrides any cultural concerns. As a result, the shelters provided in such circumstances are indistinct and impersonal. However, taking individual and cultural aspects into account might lead to a better identification of the population with their new environment, thereby minimizing the rupture caused in their lives. As the methodology to develop new housing systems is based on the idea of architectural precedents, choosing existing vernacular housing as a precedent permits the incorporation of cultural aspects and facilitates an identification of people with the new housing. In the Haiti case study, we chose as a precedent a housetype called "gingerbread houses", which includes a wide range of houses from wealthy to very humble ones. Although the proposed design system was inspired by these houses, it was decided to adopt a contemporary take. The methodology to devise the new type was based on two ideas: precedents and transformations in design. In architecture, the use of precedents provides designers with typical solutions for particular problems and it constitutes a departing point for a new design. In our case, the precedent is an existing housetype. It has been shown (Duarte, 2001) that a particular housetype can be encoded by a shape grammar (Stiny, 1980) forming a design system. Studies in shape grammars have shown that the evolution of one style into another can be described as the transformation of one shape grammar into another (Knight, 1994). The used methodology departs takes off from these ideas and it comprises the following steps (Duarte, 2008): (1) Selection of precedents, (2) Derivation of an archetype, (3) Listing of rules, (4) Derivation of designs, (5) Cataloguing of solutions, (6) Derivation of tailored solution.
Schlueter, Arno. "Integrated Design Process for Prefabricated Façade Modules with Embedded Distributed Service Systems." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 419-434. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The awareness of the environmental impact of buildings concerning their CO2 emissions, their energy and resource consumption has raised the challenges on building design, construction and operation. Building service systems are among the main contributors to building related emissions. Their consideration already in design is therefore of growing importance. Distributed service systems represent a new paradigm towards the supply of a building with energy and matter. Being small, efficient and networked, they can be distributed within the building fabric to allow an efficiently supply of the building space. Their employment, however, affects the spatial layout, construction and resulting building performance. In order to capture the resulting complex dependencies, a strategy to integrate such systems into the architectural design process is necessary. In this work a design process is proposed, that integrates distributed service systems into building design, dissolving the classical divide between architectural design and service systems layout. Digital modelling and computational methods are employed to create and analyse design solutions, visualize performance criteria and provide the relevant data for the intended digital fabrication process. The process is exemplified using a joint university-industry case study project focusing on parametric façade modules, developed in a seamless digital process from concept to fabrication.
Georgiou, Odysseas. "Interactive Structural Analysis ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 833-846. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. This paper re-approaches structural engineering through an interactive perspective by introducing a series of tools that concatenate parametric design with structural analysis, thus achieving interoperability between form and its structural performance. Parametric Design is linked to Structural Analysis using computer programming to establish a common interactive framework that leads to performance based designs that respond to structural constrains and conditions in an interactive manner. A series of examples illustrate the synergy between form and structure by interactively modelling, analysing and visualizing its response.  
Park, Hyoung-June. "Mass-Customization in the Design of 4,000 Bus Stops ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 265-278. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. In Hawaii, "TheBus" has been a main transportation system since 1971. Considering the high cost of living in Hawaii and the absence of a rail system, the use of "TheBus" has been an instrumental vein of the city life in Honolulu with rhythmical pauses at about 4,000 bus stops in Honolulu. However, existing undifferentiated bus stops are developed from a cost effective mass production system so that they have been problematic for satisfying specific needs from various site conditions. In this research, an integrated computational method of mass-customization for designing 4,000 bus stops is introduced. According to various site conditions, the design of each bus stop is customized. Unlike the mass produced bus stops commonly seen in cities today, the proposed computational method in this paper produces bus stop design outcomes that fit into the physical characteristics of the location in which they are installed. Mass-customization allows for the creation and production of unique or similar buildings and building components, differentiated through digitally controlled variation (Kolarevic, 2003). The employment of a computational mass  customization in architectural design extends the boundary of design solutions to the satisfaction of multi-objective requirements and unlimited freedom to search alternative solutions (Duarte, 2001, Caldas, 2006). The computational method developed in this paper consists of 1) definition of a prototype, 2) parametric variation, 3) manual deformation, and 4) simulation based deformation. The definition of a prototype is the development of a basic design to be transformed for satisfying various conditions given from a site. In this paper, the bus stop prototype is developed from the analysis of more than 300 bus stops and the categorization of the existing bus stops according to their physical conditions, contextual conditions, climatic conditions, and existing amenities. Based upon the outcome of the analysis, the design variables of a bus stop prototype are defined. Those design variables then guide the basic physical parameters for changing the physical configuration of the prototype according to a given site. From this, many possible design outcomes are generated as instances for further developments. The process of manual deformation is where the designer employs its intuition to develop the selected parametric variation. The designer is compelled to think about the possible implication derived from formal variation. This optional process allows every design decision to have a creative solution from an individual designer with an incidental quality in aesthetics, but substantiated functional quality. Finally the deformation of the selection is guided and controlled by the influence of sun direction/ exposure to the selection. The simulation based deformation starts with the movement of the sun as the trigger for generating the variations of the bus stop prototype. The implementation of the computational method was made within the combination of MEL (Maya Enbedded Language), autodesk MAYA and Ecotect environment. 
Vermeersch, Peter-Willem, Nijs Greg, and Heylighen Ann. "Mediating Objects in Architectural Design: a Non-Visual Exploration." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 721-734. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Through their daily interactions with the built environment, people with disabilities become able to appreciate spatial qualities or detect obstacles that architects may not be attuned to. This observation motivated us to explore scenarios for involving people with sensory disabilities as experts in the design process. An architecture office participating in a real-world design competition is teamed up with two blind persons. The design process is studied in real time through a team ethnography. The analysis in this paper focuses on the mediating aspects of objects in the actions, perception and cognition in one collaborative design meeting in particular. In general, disability situations can teach us something about fixed ways of doing by making perceivable, or questioning practices that seem self-evident. In this particular situation, the blind person's involvement in a design meeting that relies heavily on representational artifacts, makes perceivable or questions everyday practices in architects” design process that are taken for granted. Examples include knowing and indicating to others where design elements are on the site, knowing what design element is being talked about, holding the element and its environment “in place”, or spatially exploring the design's spatial configuration. As such, our study shows that exploring inclusivity “upstream”, i.e. in the design process, may contribute not only to inclusive design, but also to a more articulate understanding of the working of mediating objects and their use in architects” design processes tout court.
Rui, Irene, and Marc Aurel Schnabel. "Multi-touch - the future of design interaction." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 557-572. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The next major revolution for design is to bring the natural user interaction into design activities. Graphical User Interfaces (GUI) brought a new approach that was more effective compared to their conventional  predecessors. In recent years, Natural User Interfaces (NUI) have advanced user experiences and multi-touch and gesture technologies provide new opportunities for a variety of potential uses in design. Much attention has been paid to leverage in the design of interactive interfaces. The mouse input and desktop screen metaphors limit the information sharing for multiple users and also delayed the direct interaction for communication between each other. This paper proposes the innovative method by integrating game engine Unity3D with multi-touch tangible interfaces. Unity3D provides a game development tool as part of its application package that has been designed to let users to focus on creating new games. However, it does not limit the usage of area to design additional game scenarios since the benefits of Unity3D is allowing users to build 3D environments with  its customizable and easy to use editor, graphical pipelines to openGL (, 2010 ). It creates Virtual Reality (VR) environments which can simulates places in the real world, as well as the virtual environments helping architects and designers to vividly represent their design concepts through 3D visualizations, and interactive media installations in a detailed multi-sensory experience. Stereoscopic displays advanced their spatial ability while solving issues to design  e.g. urban spaces. The paper presents how  a multi-touch tabletop can be used for these design collaboration and communication tasks. By using natural gestures, designers can now communicate and share their ideas by manipulating the same reference simultaneously using their own input simultaneously. Further studies showed that 3Dl forms are perceived and understood more readily through haptic and proprioceptive perception of tangible representations than through visual representation alone (Gillet et al, 2005). Based on the authors framework presented at the last CAADFutures, the benefits of integrating 3D visualization and tactile sensory can be illustrated in this platform (Chen and Wang, 2009), For instance, more than one designer can manipulate the 3D geometry objects on tabletop directly and can communicate successfully their ideas freely without having to waiting for the next person response. It made the work more effective which increases the overall efficiency. Designers can also collect the real-time data by any change they make instantly. The possibilities of Uniy3D make designing very flexible and fun, it is deeply engaging and expressive. Furthermore, the unity3D is revolutionizing the game development industry, its breakthrough development platform for creating highly interactive 3D content on the web (, 2010) or similar to the interface of modern multimedia devices such as the iPhone, therefore it allows the designers to work remotely in a collaborative way to integrate the design process by using the individual mobile devices while interacting design in a common platform.  In design activities, people create an external representation of a domain, often of their own ideas and understanding. This platform helps learners to make their ideas concrete and explicit, and once externalized, subsequently they reflect upon their work how well  it sits the real situation. The paper demonstrates how this tabletop innovatively replaces the typical desktop metaphor. In summary, the paper  addresses two major issues through samples of collaborative design: firstly presenting aspects of learners interactions with physical objects, whereby tangible interfaces enables them constructing expressive representations passively (Marshall, 2007), while focussing on other tasks, and secondly showing how this novel design tool allows designers to actively create constructions that might not be possible with conventional media.
Chasznar, Andre. "Navigating Complex Models in Collaborative Work for (Sustainably) Integrated Design." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 619-636. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Increasingly intensive use of computational techniques such as parametric-associative modeling, algorithmic design, performance simulations and generative design in architecture, engineering and construction are leading to increasingly large and complex 3D building models which in turn require increasingly powerful techniques in order to be manipulated and interpreted effectively. Further complexities are of course due also to the multi-disciplinary nature of building projects, in which there can be significant variation and even conflict among the aims of architects, engineers and builders, as well as owners, occupants and other stakeholders in the process. Effective use of model information depends to a large extent on sense-making, which can in some ways be helped but also hindered by schemes for organizing the information contained. Common techniques such as layering, labeling (aka tagging) and assignment of various other attributes to model objects have significant limitations  especially those arising from general problems of language, ontology and standardization, as well as but distinct from issues of interoperability  both with respect to locating the desired items in a 3D building model and also with respect to displaying the objects in informative ways which effectively assist collaborative design and decision-making. Sustainable design in particular is an area generally requiring a high level of inter-disciplinary collaboration to achieve highly integrated designs which make multiple use of the elements and systems incorporated (though integrated design may also be pursued without explicit aims of sustainability). The proposed paper describes ongoing research concerning alternatives to the currently common techniques for locating and displaying information in 3D building models in support of sense-making to promote collaborative and integrated design. These alternatives comprise on the one hand interactive geometric-content-based methods for search and classification of model objects  as an alternative or complement to common assigned-attribute-based methods  and on the other hand visual analytic techniques in contrast to existing, relatively static tabular and "physical" views  which can help to increase the informativeness of the geometric data within the model, as well as the non-geometric data that is attached to geometric objects (e.g. as in the cases of BIM and various types of CAE performance simulations). Tests undertaken with architects and engineers in practice and academia to evaluate the proposed methods are also described. Finally conclusions are drawn regarding these methods positive present performance and some of their shortcomings, as well as indicating directions for future research concerning the methods refinement and extension to help 3D building models become more effective components of the design process than they are at present, both with respect to these models present levels of complexity and especially with respect to their anticipated increasing complexity in future. 
Stavric, Milena, and Wiltsche Albert. "Ornamental Plate Shell Structures." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 817-832. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The development of digital technologies in the last twenty years has led to an unprecedented formal freedom in design and in the representation in virtual space. Combining non-standard geometry with CAD tools enables a new way of expression and realization of architectural ideas and conceptions. The transformation of a virtual double-curved surface into a buildable physical structure and object is always accompanied by huge costs and big problems like geometric and statical ones. Our structure is a type of shell structure consisting of plane panels. The load bearing system is organized in a way so that the forces are distributed along the edges of the plane elements. A structure with plane elements supports a high stiffness in combination with a relatively small overall weight. This is due to smooth curved shape of the geometry. We show geometric methods how to control the construction of curved surfaces out of planar building elements. The approach is based on the discretization of the surfaces by plane elements derived from tangent planes. The novel process in this work is that we take the surface curvature at local points into account. This solves former problems which occurred when intersecting the planes. The fact that there is an infinite number of possibilities when selecting tangent planes on a surface raises the issue of the way and conditions which make it possible to select specific tangent planes whose intersection would produce a desired three-dimensional shape. In order to satisfy also aesthetical requirements we engage plane geometrical patterns and ornaments and transfer them into spatial shape. So a three-dimensional ornamental shape is deduced from a two-dimensional ornament. Another task which will be showed is how to limit the infinite range of possibilities to generate a preferred spatial ornament and on what conditions surface tessellation would be ornamental in character, i.e. it would generate not only the functional, but also the aesthetic component of a free-form surface. 
Ciblac, Thierry. "Parametric Design with Standard Elements for Non-Standard Architecture." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 119-132. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The development of non-standard architecture is often combined with the use of non-standard elements. But for economical or sustainable reasons, the use of standard elements may be particularly useful. The introduction of standard elements adapted to geometries far from parallelepipeds and freely designed raises a specific problem. The aim of this paper is to explore some ways offered by computing tools in order to help architects in the design process of non-standard shapes using standard elements. An approach is proposed for a specific typology of systems composed of constant length elements. The method used herein is based on parametric modeling associated with constraint resolution algorithms. (short abstract because full paper already written)
Chen, Liang, and Ng Edward. "PedNaTAS: an Integrated Multi-Agent Based Pedestrian Thermal Comfort Assessment System." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 735-750. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Pedestrian's thermal comfort is of great importance in urban planning. To develop effective planning standards that prompt pedestrian comfort, a comprehensive assessment framework that takes into account pedestrian's individual perception and behavioral is in great need. Computer simulation tools in this respect are still sparse. This paper presents the PedNaTAS system, an agent-based integrated decision support system that assesses pedestrian thermal comfort from bottom-up.
Sheward, Hugo, and Eastman Charles. "Preliminary Concept Design (PCD) Tools for Laboratory Buildings, Automated Design Optimization and Assessment Embedded in Building Information Modeling (BIM) Tools." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 451-476. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The design of laboratory buildings entails the implementation of a variety of design constraints such as building codes, design guidelines and technical requirements. The application of these requires from designers the derivation of data not explicitly available at early stages of design, at the same time there is no precise methodology to control the consistency, and accuracy of their application. Many of these constraints deal with providing secure environmental conditions for the activities inside laboratories and their repercussions both for the building occupants and population in general, these constraints mandate a strict control over the building's Mechanical Equipment (MEP), in particular the Heating Ventilating and Air Conditioning (HVAC) system. Due to the importance of these laboratory designers are expected to assess their designs not only according spatial relationships, but also design variables such as HVAC efficiency, air pressure hierarchies, operational costs, and the possible implications of their design decisions in the biological safety of the facility. At this point in time, there are no practical methods for making these assessments, without having constant interaction with HVAC specialists. The assessment of laboratory design variables, particularly those technical in nature, such as dimensioning of ducts or energy consumption are usually performed at late stages of design. They are performed by domain experts using data manually extracted from design information, with the addition of domain specific knowledge, the evaluation is done mostly through manual calculations or building simulations. In traditional practices most expert evaluations are performed once the architectural design have been completed, the turn around of the evaluation might take hours or days depending on the methods used by the engineer, therefore reducing the possibility for design alternatives evaluation. The results of these evaluations will give clues about sizing of the HVAC equipment, and might generate the need for design reformulations, causing higher development costs and time delays. Several efforts in the development of computational tools for automated design evaluation such as wheel chair accessibility (Han, Law, Latombe, Kunz, 2002) security and circulation (Eastman, 2009), and construction codes ( have demonstrated the capabilities of rule or parameter based building assessment, several computer applications capable of supporting HVAC engineers in system designing for late concept or design development exist, but little has been done to assess the capabilities of computer applications to support laboratory design during architectural Preliminary Concept Design(PCD) (Trcka, Hensen, 2010). Developments in CAD technologies such as Building Information Modeling (BIM) have opened doors to formal explorations in generative design using rule based or parametric modeling [7]. BIM represents buildings as a collection of objects with their own geometry, attributes, and relations. BIM also allows for the definition of objects parametrically including their relation to other model objects. BIM has enabled the development of automated rule based building evaluation (Eastman, 2009). Most of contemporary BIM applications contemplate in their default user interfaces access to design constraints and object attribute manipulations. Some even allow for the application of rules over these. Such capabilities make BIM viable platforms for automation of design data derivation and for the implementation of generative based design assessment. In this paper we analyze the possibilities provided by contemporary BIM for implementing generative based design assessment in laboratory buildings. In this schema, domain specific knowledge is embedded in to the BIM system as to make explicit design metrics that can help designers and engineers to assess the performance of design alternatives. The implementation of generative design assessments during PCD can help designers and engineers to identify design issues early in the process, reducing the number of revisions and reconfigurations in later stages of design. And generally improving design performance. 
Pohl, Ingrid, and Urs Hirschberg. "Sensitive Voxel - a reactive tangible surface ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 525-538. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Haptic and tactile sensations, the active or passive exploration of our built surroundings through our sense of touch, give us a direct feeling and detailed information of space, a sense of architecture (Pallasmaa 2005). This paper presents the prototype of a reactive surface system, which focuses its output on the sense of touch. It explains how touch sensations influence the perception of architecture and discusses potential applications that might arise from such systems in the future. A growing number of projects demonstrate the strong impact of interaction design on the human senses and perception. They offer new ways of sensing and experiencing architectural space. But the majority of these interaction concepts focus on visual and auditory output-effects. The sense of touch is typically used as an input generator, but neglected as as a potential receiver of stimuli. With all the possibilities of sensors and micro-devices available nowadays, there is no longer a technical reason for this. It is possible to explore a much wider range of sense responding projects, to broaden the horizon of sensitive interaction concepts (Bullivant 2006). What if the surfaces of our surroundings can actively change the way it feels to touch them? What if things like walls and furniture get the ability to interactively respond to our touch? What new dimensions of communication and esthetic experience will open up when we conceive of tangibility in this bi-directional way? This paper presents a prototype system aimed at exploring these very questions. The prototype consists of a grid of tangible embedded cells, each one combining three kinds of actuators to produce divergent touch stimuli. All cells can be individually controlled from an interactive computer program. By providing a layering of different combinations and impulse intensities, the grid structure enables altering patterns of actuation. Thus it can be employed to explore a sort of individual touch aesthetic, for which - in order to differentiate it from established types of aesthetic experiences - we have created the term'Euhaptics'(from the Greek ŒµœÖ = good and Œ¨œÄœÑœâ = touch, finger). The possibility to mix a wide range of actuators leads to blending options of touch stimuli. The sense of touch has an expanded perception- spectrum, which can be exploited by this technically embedded superposition. The juxtaposed arrangement of identical multilayered cell-units offers blending and pattern effects of different touch-stimuli. It reveals an augmented form of interaction with surfaces and interactive material structures. The combination of impulses does not need to be fixed a priori; it can be adjusted during the process of use. Thus the sensation of touch can be made personally unique in its qualities. The application on architectural shapes and surfaces allows the user to feel the sensations in a holistic manner ‚Äì potentially on the entire body. Hence the various dimensions of touch phenomena on the skin can be explored through empirical investigations by the prototype construction. The prototype system presented in the paper is limited in size and resolution, but its functionality suggests various directions of further development. In architectural applications, this new form of overlay may lead to create augmented environments that let inhabitants experience multimodal touch sensations. By interactively controlling the sensual patterns, such environments could get a unique ‚Äútouch‚Äù for every person that inhabit them. But there may be further applications that go beyond the interactive configuration of comfort, possibly opening up new forms of communication for handicapped people or applications in medical and therapeutic fields (Grunwald 2001). The well-known influence of touch- sensations on human psychological processes and moreover their bodily implications suggest that there is a wide scope of beneficial utilisations yet to be investigated.
Langenhan, Christoph, Weber Markus, Frank Petzold, Liwicki Marcus, and Dengel Andreas. "Sketch-based Methods for Researching Building Layouts through the Semantic Fingerprint of Architecture." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 85-102. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The paper focuses on the early stages of the design process where the architect needs assistance in finding reference projects and describes different aspects of a concept for retrieving previous design solutions with similar layout characteristics. Such references are typically used to see how others have solved a similar architectural problem or simply for inspiration. Current electronic search methods use textual information rather than graphical information. The configuration of space and the relations between rooms are hard to represent using keywords, in fact transforming these spatial configurations into verbally expressed typologies tends to result in unclear and often imprecise descriptions of architecture. Nowadays, modern IT-technologies lead to fundamental changes during the process of designing buildings. Digital representations of architecture require suitable approaches to the storage, indexing and management of information as well as adequate retrieval methods. Traditionally planning information is represented in the form of floor plans, elevations, sections and textual descriptions. State of the art digital representations include renderings, computer aided design (CAD) and semantic information like Building Information Modelling (BIM) including 2D and 3D file formats such as Industry Foundation Classes (IFC) (IAI, 2010). In the paper, we examine the development of IT-technologies in the area of case-based reasoning (Richter et al., 2007) to provide a sketch-based submission and retrieval system for publishing and researching building layouts including their manipulation and subsequent use. The user interface focuses on specifying space and their relations by drawing them. This query style supports the spatial thinking approach that architects use, who often have a visual representation in mind without being able to provide an accurate description of the spatial configuration. The semantic fingerprint proposed by (Langenhan, 2008) is a description and query language for creating an index of floor plans to store meta-data about architecture, which can be used as signature for retrieving reference projects. The functional spaces, such as living room or kitchen and the relation among on another, are used to create a fingerprint. Furthermore, we propose a visual sketch-based interface (Weber et al., 2010) based on the Touch&Write paradigm (Liwicki et al., 2010) for the submission and the retrieval phase. During the submission process the architect is sketching the space-boundaries, space relations and functional coherence's. Using state of the art document analysis techniques, the architects are supported offering an automatic detection of room boundaries and their physical relations. During the retrieval the application will interpret the sketches of the architect and find reference projects based on a similarity based search utilizing the semantic fingerprint. By recommending reference projects, architects will be able to reuse collective experience which match the current requirements. The way of performing a search using a sketch as a query is a new way of thinking and working. The retrieval of 3D models based on a sketched shape are already realized in several domains. We already propose a step further, using the semantics of a spatial configuration. Observing the design process of buildings reveals that the initial design phase serves as the foundation for the quality of the later outcome. The sketch-based approach to access valuable information using the semantic fingerprint enables the user to digitally capture knowledge about architecture, to recover and reuse it in common-sense. Furthermore, automatically analysed fingerprints can put forward both commonly used as well as best practice projects. It will be possible to rate architecture according to the fingerprint of a building.
Merrick, Kathryn, and GU Ning. "Supporting Collective Intelligence for Design in Virtual Worlds: a Case Study of the Lego Universe." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 637-652. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Virtual worlds are multi-faceted technologies. Facets of virtual worlds include graphical simulation tools, communication, design and modelling tools, artificial intelligence, network structure, persistent object-oriented infrastructure, economy, governance and user presence and interaction. Recent studies (Merrick et al., 2010) and applications (Rosenman et al., 2006, Maher et al., 2006) have shown that the combination of design, modelling and communication tools, and artificial intelligence in virtual worlds makes them suitable platforms for supporting collaborative design, including human-human collaboration and human-computer co-creativity. Virtual worlds are also coming to be recognised as a platform for collective intelligence (Levy, 1997), a form of group intelligence that emerges from collaboration and competition among large numbers of individuals. Because of the close relationship between design, communication and virtual world technologies, there appears a strong possibility of using virtual worlds to harness collective intelligence for supporting upcoming design challenges on a much larger scale as we become an increasingly global and technological society (Maher et al, 2010), beyond the current support for small-scale collaborative design teams. Collaborative design is relatively well studied and is characterised by small-scale, carefully structured design teams, usually comprising design professionals with a good understanding of the design task at hand. All team members are generally motivated and have the skills required to structure the shared solution space and to complete the design task. In contrast, collective design (Maher et al, 2010) is characterised by a very large number of participants ranging from professional designers to design novices, who may need to be motivated to participate, whose contributions may not be directly utilised for design purposes, and who may need to learn some or all of the skills required to complete the task. Thus the facets of virtual worlds required to support collective design differ from those required to support collaborative design. Specifically, in addition to design, communication and artificial intelligence tools, various interpretive, mapping and educational tools together with appropriate motivational and reward systems may be required to inform, teach and motivate virtual world users to contribute and direct their inputs to desired design purposes. Many of these world facets are well understood by computer game developers, as level systems, quests or plot and achievement/reward systems. This suggests the possibility of drawing on or adapting computer gaming technologies as a basis for harnessing collective intelligence in design. Existing virtual worlds that permit open-ended design  such as Second Life and There are not specifically game worlds as they do not have extensive level, quest and reward systems in the same way as game worlds like World of Warcraft or Ultima Online. As such, while Second Life and There demonstrate emergent design, they do not have the game-specific facets that focus users towards solving specific problems required for harnessing collective intelligence. However, a new massively multiplayer virtual world is soon to be released that combines open-ended design tools with levels, quests and achievement systems. This world is called Lego Universe ( This paper presents technology spaces for the facets of virtual worlds that can contribute to the support of collective intelligence in design, including design and modelling tools, communication tools, artificial intelligence, level system, motivation, governance and other related facets. We discuss how these facets support the design, communication, motivational and educational requirements of collective intelligence applications. The paper concludes with a case study of Lego Universe, with reference to the technology spaces defined above. We evaluate the potential of this or similar tools to move design beyond the individual and small-scale design teams to harness large-scale collective intelligence. We also consider the types of design tasks that might best be addressed in this manner. 
Bittermann, Michael. "Sustainable Conceptual Building Design using a Cognitive System." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 297-314. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. A cognitive system for conceptual building design is presented. It is based on an adaptive multi-objective evolutionary algorithm. The adaptive approach is novel and, in contrast with conventional multi-objective evolutionary algorithms, it explores the solution space effectively, while maintaining diversity among the solutions. The suitability of the approach for conceptual design of a multi-purpose building complex is demonstrated in an application. In the application, the goal of maximizing sustainability is treated by means of a model, which is established using neural computations. The approach is found to be suitable for treating the soft nature of the sustainability concept. Also, the capability of the approach to compare the performance of alternative solutions from an unbiased viewpoint, i.e. without committing a-priori to a relative importance among the performance aspects, is demonstrated.
Ng, Edward, and Ren Chao. "Sustainable Planning with a Synergetic Collation of Thermal and Dynamic Characteristics of Urban Climate using Map Based Computational Tools." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 367-382. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Since 2006, half of the world's population lives in cities. In the age of climate change, designing for quality environmental living conditions and sustainability is a topical concern.  However, on the one hand, designers and city planners operate with their three dimensional city morphological data such as building shapes and volumes, forms and their spacings, and functional attributes and definition signatures. On the other hand, urban climatologists operate with their numbers and equations, quantities and signals, and normals and anomalies. Traditionally the two camps do not meet. It is a challenge to develop design tools that they can work together. Map based information system based on computational geographic information system (GIS) that is properly structured and represented offers a common language, so to speak, for the two professional groups to work together. Urban climatic map is a spatial and graphical tool with information embedded in defined layers that are collated so that planners and urban climatologists can dialogue over design issues. With various planning and meteorological data coded in defined grid resolutions onto the GIS map system, data can be synergized and collated for various understandings. This papers explains the formulation of Hong Kong's GIS based Urban Climatic Map as an example of how the map works in practice. Using the map, zonal and district based planning decisions can be made by planners and urban climatologists that lead to new designs and policy changes. 
Barros, Mário, and Chaparro José. "Thonet Chairs Design Grammar: a Step Towards the Mass Customization of Furniture." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 181-200. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. This paper proposes a reflection upon the teaching of architecture as seen from the actual practice of the profession within the context of the changes caused by the widespread use of computers and Internet in recent years. This proposal designates the present time as “semic revolution”, superseding denominations like post industriali or information revolutioni, emphasizing that the “mental prosthesis” created by man represents the highest degree of exploitation of his innerness as a “semic subject”. A brief epistemological framework serves to lay the foundation for the concepts of imagination, creation, and design, differentiating the creator by his characteristic of requiring or not, semic mediation in order to reach his goals. The dominant use of new instruments which serve to represent and operate the “primary virtual objecti giving priority to the comprehension and function of the new tool over the acquisition of information and ability to use it, is proposed when carried over to the field of application. The integration of internal networks through email strives not only to facilitate document transmission, exercises, group work, etc. but to understand the new dimension in the intellectual activities of man.
Bernal, Marcelo, and Eastman Charles. "Top-down Approach for Interaction of Knowledge-Based Parametric Objects and Preliminary Massing Studies for Decision Making in Early Design Stages." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 149-164. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Design activities vary from high-degree of freedom in early concept design stages to highly constrained solution spaces in late ones. Such late developments entail large amount of expertise from technical domains. Multiple parallel models handle different aspects of a project, from geometric master models to specific building components. This variety of models must keep consistency with the design intent while they are dealing with specific domains of knowledge such as architectural design, structure, HVAC, MEP, or plumbing systems. Most of the expertise embedded within the above domains can be translated into parametric objects by capturing design and engineering knowledge through parameters, constraints, or conditionals. The aim of this research is capturing such expertise into knowledge-based parametric objects (KPO) for re-usability along the design process. The proposed case study's provided by SOM New York's is the interaction between a massing study of a high-rise and its building service core, which at the same time handles elevators, restrooms, emergency stairs, and space for technical systems. This project is focused on capturing design expertise, involved in the definition of a building service core, from a high-rise senior designer, and re-using this object for interaction in real-time with a preliminary massing study model of a building, which will drive the adaption process of the service core. This interaction attempts to provide an integrated design environment for feedback from technical domains to early design stages for decision-making, and generate a well-defined first building draft. The challenges addressed to drive the instantiation of the service core according to the shifting characteristics of the high-rise are automatic instantiation and adaptation of objects based on decision rules, and updating in real-time shared parameters and information derived from the high-rise massing study. The interaction between both models facilitates the process from the designer´s perspective of reusing previous design solutions in new projects. The massing study model is the component that handles information from the perspective of the outer shape design intent. Variations at this massing study model level drive the behavior of the service core model, which must adapt its configuration to the shifting geometry of the building during design exploration in early concept design stages. These variations depend on a list of inputs derived from multiple sources such as variable lot sizes, building type, variable square footage of the building, considerations about modularity, number of stories, floor-to-floor height, total building height, or total building square footage. The shifting combination of this set of parameters determines the final aspect of the building and, consequently, the final configuration of the service core. The service core is the second component involved in the automatic generation of a building draft. In the context of BIM, it is an assembly of objects, which contains other objects representing elevators, restrooms, emergency stairs, and space for several technical systems. This assembly is driven by different layouts depending on the building type, a drop-off sequence, which is the process of continuous reduction of elevators along the building, and how this reduction affects the re-arrangement of the service core layout. Results from this research involves a methodology for capturing design knowledge, a methodology for defining the architecture of smart parametric objects, and a method for real-time-feedback for decision making in early design stages. The project also wants to demonstrate the feasibility of continuous growth on top of existing parametric objects allowing the creation of libraries of smart re-usable objects for automation in design. 
Calderon, Dominguez, Emmanuel Ruffo, and Urs Hirschberg. "Towards a Morphogenetic Control of Free-Form Surfaces for Designers." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 165-180. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011.

The present paper discusses a novel computational design strategy for approximating architectural free form geometry with discrete planar elements by using morphogenetic patterns. We report on an ongoing research project,1 which is focused on the design of flat ornamental tessellations by using computational geometry for the discretization of curved forms rather than manufacturing curvy elements, which typically increase cost. The significance of our approach lies in the fact that it allows the designer to progressively embrace the constructive constraints and their esthetic potential already in the design stage and to follow them through to actual fabrication.

  • 1. Ornamental design here means a self-structural and tessellated component embedding a whole system of patterns conceived already in the design stage rather than ornament as one-function decorative instrument in architectural design.
Boton, Conrad, Kubicki Sylvain, and Gilles Halin. "Understanding Pre-Construction Simulation Activities to Adapt Visualization in 4D CAD Collaborative Tools." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 477-492. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Increasing productivity and efficiency is an important issue in the AEC field. This area is mainly characterized by fragmentation, heterogeneous teams with low lifetimes and many uncertainties. 4D CAD is one of the greatest innovations in recent years. It consists in linking a 3D model of the building with the works planning in order to simulate the construction evolution over time. 4D CAD can fill several needs from design to project management through constructivity analysis and tasks planning (Tommelein 2003). The literature shows that several applications have been proposed to improve the 4D CAD use (Chau et al. 2004, Lu et al. 2007, Seok & al. 2009). In addition, studies have shown the real impact of 4D CAD use in construction projects (Staub-French & Khanzode 2007, Dawood & Sika 2007). More recently, Mahalingam et al. (2010) showed that the collaborative use of 4D CAD is particularly useful during the pre-construction phase for comparing the constructability of working methods, for visually identifying conflicts and clashes (overlaps), and as visual tool for practitioners to discuss and to plan project progress. So the advantage of the 4D CAD collaborative use is demonstrated. Moreover, several studies have been conducted both in the scientific community and in the industrial world to improve it (Zhou et al. 2009, Kang et al. 2007). But an important need that remains in collaborative 4D CAD use in construction projects is about the adaptation of visualization to the users business needs. Indeed, construction projects have very specific characteristics (fragmentation, variable team, different roles from one project to another). Moreover, in the AEC field several visualization techniques can represent the same concept and actors choose one or another of these techniques according to their specific needs related to the task they have to perform. For example, the tasks planning may be represented by a Gantt chart or by a PERT network and the building elements can be depicted with a 3D model or a 2D plan. The classical view (3D + Gantt) proposed to all practitioners in the available 4D tools seems therefore not suiting the needs of all. So, our research is based on the hypothesis that adapting the visualization to individual business needs could significantly improve the collaboration. This work relies on previous ones and aim to develop a method 1) to choose the best suited views for performed tasks and 2) to compose adapted multiple views for each actor, that we call business views. We propose a 4 steps-method to compose business views. The first step identifies the users business needs, defining the individual practices performed by each actor, identifying his business tasks and his information needs. The second step identifies the visualization needs related to the identified business needs. For this purpose, the user's interactions and visualization tasks are described. This enables choosing the most appropriate visualization techniques for each need (step 3). At this step, it is important to describe the visualization techniques and to be able to compare them. Therefore, we proposed a business view metamodel. The final step (step 4) selects the adapted views, defines the coordination mechanisms and the interaction principles in order to compose coordinated visualizations. A final step consists in a validation work to ensure that the composed views really match to the described business needs. This paper presents the latest version of the method and especially presents our latest works about its first and second steps. These include making more generic the business tasks description in order to be applicable within most of construction projects and enabling to make correspondence with visualization tasks.
Nguyen, Thi, and Tan Kiang. "Understanding Shared Space for Informal Interaction among Geographically Distributed Teams." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 41-54. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. In a design project, much creative work is done in teams, thus requires spaces for collaborative works such as conference rooms, project rooms and chill-out areas. These spaces are designed to provide an atmosphere conducive to discussion and communication ranging from formal meetings to informal communication. According to Kraut et al (E.Kraut et al., 1990), informal communication is an important factor for the success of collaboration and is defined as a conversations take place at the time, with the participants, and about the topics at hand. It often occurs spontaneously by chance and in face-to-face manner. As shown in many research, much of good and creative ideas originate from impromptu meeting rather than in a formal meeting (Grajewski, 1993, A.Isaacs et al., 1997). Therefore, the places for informal communication are taken into account in workplace design and scattered throughout the building in order to stimulate face-to-face interaction, especially serendipitous communication among different groups across disciplines such as engineering, technology, design and so forth. Nowadays, team members of a project are not confined to people working in one location but are spread widely with geographically distributed collaborations. Being separated by long physical distance, informal interaction by chance is impossible since people are not co-located. In order to maintain the benefit of informal interaction in collaborative works, research endeavor has developed a variety ways to shorten the physical distance and bring people together in one shared space. Technologies to support informal interaction at a distance include video-based technologies, virtual reality technologies, location-based technologies and ubiquitous technologies. These technologies facilitate people to stay aware of other's availability in distributed environment and to socialize and interact in a multi-users virtual environment. Each type of applications supports informal interaction through the employed technology characteristics. One of the conditions for promoting frequent and impromptu face-to-face communication is being co-located in one space in which the spatial settings play as catalyst to increase the likelihood for frequent encounter. Therefore, this paper analyses the degree to which sense of shared space is supported by these technical approaches. This analysis helps to identify the trade-off features of each shared space technology and its current problems. A taxonomy of shared space is introduced based on three types of shared space technologies for supporting informal interaction. These types are named as shared physical environments, collaborative virtual environments and mixed reality environments and are ordered increasingly towards the reality of sense of shared space. Based on the problem learnt from other technical approaches and the nature of informal interaction, this paper proposes physical-virtual shared space for supporting intended and opportunistic informal interaction. The shared space will be created by augmenting a 3D collaborative virtual environment (CVE) with real world scene at the virtual world side, and blending the CVE scene to the physical settings at the real world side. Given this, the two spaces are merged into one global structure. With augmented view of the real world, geographically distributed co-workers who populate the 3D CVE are facilitated to encounter and interact with their real world counterparts in a meaningful and natural manner.
Verdonck, Evelien, and Froyen Hubert. "Universal Design Patterns: Designing a Web-Based Tool with Architects." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 103-115. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The implementation of Universal Design in design practice requires a number of tools that provide support to designers throughout the design process. In recent years, several studies have been carried out, determining methods to help designers select appropriate design support tools (DSTs), looking for desired data representation characteristics, or focusing on involving a wide range of users in the design process. This paper discusses how architects, as end-users of the DST, are involved in the development process of a new web-based tool based on the Universal Design Patterns concept. The Universal Design Pattern concept was developed based on Christopher Alexander's Pattern Language, and looks at the possibility of using patterns to describe existing barriers in the built environment (conflicts), as well as design characteristics that may be implemented to make new designs more inclusive (resolutions). Through Universal Design Patterns, users can contribute new insights about the existing built environment, while architects can discuss the inclusive qualities of new design solutions or find useful design guidance. Involving the architects in developing the Universal Design Pattern concept into a web-based design tool is essential to establish a structure for the Universal Design Patterns that is compatible with the designers way of thinking about design problems. Using the specific structure of Universal Design Patterns allows for the grouping of information into appropriately themed units on different levels of the design in a clear and uniform way. Building on the results of a survey involving 406 architects and a comparative study of existing DSTs for Universal Design, this paper first focuses on the results of a series of interviews that provided the basis for a first data-structure for the Universal Design Patterns tool. In addition to this, case-studies were carried out to ensure the new tool can easily be incorporated into the architects design process. The results from both the interviews and the case-studies were combined in a preliminary model for the web-based tool. Finally, the methodology for testing this model with architects is discussed. In conclusion, some thoughts are given on the potential benefits of not only testing new DSTs with designers, but involving them actively from the early stages, or, in other words, the benefits of tools not only designed for architects, but with them. 
Davis, Daniel, Mark Burry, and Jane Burry. "Untangling Parametric Schemata: Enhancing Collaboration Through Modular Programming." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 55-68. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Presently, collaboration is difficult on large and complex parametric models due to the illegibility of unstructured schemata. This lack of legibility makes it hard for an outside author to understand the model, reducing their ability to edit and share the model. This paper investigates whether the legibility of parametric models is enhanced through restructuring the schema with modular programming principles. During a series of thinking-aloud interviews, designers asked to describe the function of unfamiliar schemata could consistently better comprehend the schemata structured with modular principles. Modular programming is found to be a small change to parametric modelling that derives clear benefits in terms of legibility, particularly when the model is large and used in a collaborative environment. 
Erbas, Irem, Bittermann Michael, and Stouffs Rudi. "Use of a Knowledge Model for Integrated Performance Evaluation for Housing (re)design Towards Environmental Sustainability: a Case Study ." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 281-296. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. This paper focuses on the development of a knowledge model in the context of energy efficiency and indoor climate interventions, their impacts on each other and on architectural design preferences (for instance architectural expression or any spatial functionality aspect) via an existing house case study. In addition, it attempts to discuss how this type of model can be a reference for a decision support tool and be applied to the (re)design of dwellings. The model is considered to provide an integral knowledge base for the design professional both to evaluate existing designs and to use it as a support during design and decision making in order to reach the best possible solution, with optimal performance in terms of indoor comfort, energy-efficiency and overall design performance. In other words, its aim is to enable the assessment of the performance of the end result with respect to design choices, beforehand. In this paper, design performance is modeled by means of fuzzy logic operations. It is a method to deal with subjective and vague requirements such as low energy consumption, low overheating risk, high comfort, etc. The method of intelligent information processing is explained and a partial application is presented.
Boeykens, Stefan. "Using 3D Design Software, BIM and Game Engines for Architectural Historical Reconstruction." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 493-509. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. The use of digital tools has become a tremendous aid in the creation of digital, historical reconstructions of architectural projects. Regular visualization techniques have been used for quite some time and they still pose interesting approaches, such as following cinematic techniques [1]. While common visualizations focus on pre-rendered graphics, it is possible to apply Game Engines [2] for real-time architectural visualization, as witnessed by [3] and [4]. In the course of our teaching and research efforts, we have collected experience with several visualization and modeling techniques, including the use of gaming engines. While the modeling of qualitative geometry for use in regular visualization already poses an elaborate effort, the preparation of models for different uses is often not trivial. Most modeling systems only support the creation of models for a single amount of detail, whereas an optimized model for a real-time system will have fairly different constraints when compared to non-real-time models for photorealistic rendering and animation. The use of parametric methods is one usable approach to tackle this complexity, as illustrated in [4]. One of the major advantages of using parametric approaches lies precisely in the possibility of using a single model to generate different geometry with control over the amount of detail. We explicitly tackle this in a Building Information Modeling (BIM) context, as to support much more than purely 3D geometry and visualization purposes. An integrated approach allows the same model to be used for technical drawings in 2D and an optimized 3D model in varying levels of detail for different visualization purposes. However, while most Building Information Modeling applications are targeted to current architectural practice, they seldom provide sufficient content for the recreation of historical models. This thus requires an extensive library of parametric, custom objects to be used and re-used for historically accurate models, which can serve multiple purposes. Finally, the approach towards the historical resources also poses interpretation problems, which we tackled using a reasonably straightforward set up of an information database, collecting facts and accuracies. This helps in the visualization of color-coded 3D models, depicting the accuracy of the model, which is a valuable graphical approach to discuss and communicate information about the historical study in an appealing format. This article will present the results of different reconstruction case studies, using a variety of design applications and discuss the inherent complexity and limitations in the process of translating an active, evolving model into an environment suitable for use in a real-time system. Especially workflow issues are identified, as the translation of the model into the game engine should be repeated several times, when the model is further refined and adapted. This used to involve a large amount of repetitive work, but the current crop of game engines have much better approaches to manage the updating of the geometry.
Khan, Mohammad, and Andy Dong. "Using Geo-Located Augmented Reality for Community Evaluation." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 701-720. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. AgentCAD is a network infrastructure of distributed CAD applications that facilitates the concurrent an cooperative interaction of several designers working together, possibly over several physical locations, on a design project. It provides a set of services and protocols that support the communications of distributed design information captured by CAD drawings, multiple design views, and design changes. It coordinates access to a common and multiple design models as well as the activities of designers based on captured knowledge of designers'tasks, capabilities, and interests, which characterize their behaviours. The idea of AgentCAD represents a departure from the usual way in which CAD applications are used as single-user tools, applied to one view of specific design problems. In describing the AgentCAD environment, we discuss the organization of AgentCAD, its communication model, and the cooperative interaction protocols for designers in the context of a design scenario.
Janssen, Patrick, and Chen Wee. "Visual Dataflow Modelling: a Comparison of Three Systems." In Designing together: Proceedings of the 14th International conference on Computer Aided Architectural Design, 801-816. CAAD Futures. Liège: Les Éditions de l'Université de Liège, 2011. Visual programming languages enable users to create computer programs by manipulating graphical elements rather than by entering text. The difference between textual languages and visual languages is that most textual languages use a procedural programming model, while most visual languages use a dataflow programming model. When visual programming is applied to design, it results in a new modelling approach that we refer to'visual dataflow modelling'(VDM). Recently, VDM has becoming increasingly popular within the design community, as it can accelerate the iterative design process, thereby allowing larger numbers of design possibilities to be explored. Furthermore, it is now also becoming an important tool in performance-based design approaches, since it may potentially enable the closing of the loop between design development and design evaluation. A number of CAD systems now provide VDM interfaces, allowing designers to define form generating procedures without having to resort to scripting or programming. However, these environments have certain weaknesses that limit their usability. This paper will analyse these weaknesses by comparing and contrasting three VDM environments: McNeel Grasshopper, Bentley Generative Components, and Sidefx Houdini. The paper will focus on five key areas: * Conditional logic allow rules to be applied to geometric entities that control how they behave. Such rules will typically be defined as if-then-else conditions, where an action will be executed if a particular condition is true. A more advanced version of this is the while loop, where the action within the loop will be repeatedly executed while a certain condition remains true. * Local coordinate systems allow geometric entities to be manipulated relative to some convenient local point of reference. These systems may be either two-dimensional or three-dimensional, using either Cartesian, cylindrical, or spherical systems. Techniques for mapping geometric entities from one coordinate system to another also need to be considered. * Duplication includes three types: simple duplication, endogenous duplication, and exogenous duplication. Simple duplication consists of copying some geometric entity a certain number of times, producing identical copies of the original. Endogenous duplication consist of copying some geometric entity by applying a set of transformations that are defined as part of the duplication process. Lastly, exogenous duplication consists of copying some geometric entity by applying a set of transformations that are defined by some other external geometry. * Part-whole relationships allow geometric entities to be grouped in various ways, based on the fundamental set-theoretic concept that entities can be members of sets, and sets can be members of other sets. Ways of aggregating data into both hierarchical and non-hierarchical structures, and ways of filtering data based on these structures need to be considered. * Spatial queries include relationships between geometric entities such as touching, crossing, overlapping, or containing. More advanced spatial queries include various distance based queries and various sorting queries (e.g. sorting all entities based on position) and filtering queries (e.g. finding all entities with a certain distance from a point). For each of these five areas, a simple benchmarking test case has been developed. For example, for conditional logic, the test case consists of a simple room with a single window with a condition: the window should always be in the longest north-facing wall. If the room is rotated or its dimensions changed, then the window must re-evaluate itself and possibly change position to a different wall. For each benchmarking test-case, visual programs are implemented in each of the three VDM environments. The visual programs are then compared and contrasted, focusing on two areas. First, the type of constructs used in each of these environments are compared and contrasted. Second, the cognitive complexity of the visual programming task in each of these environments are compared and contrasted.