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CumInCAD is a Cumulative Index about publications in Computer Aided Architectural Design
supported by the sibling associations ACADIA, CAADRIA, eCAADe, SIGraDi, ASCAAD and CAAD futures

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_id	252a
authors	Reich, Yoram
year	1988
title	Machine Learning for Expert Systems : Motivation and Techniques
source	i-iii, 51 p. : some ill Pittsburgh, PA: Engineering Design Research Center, CMU, June, 1988. EDRC 12-27-88. includes bibliography. First generation expert systems suffer from two major problems: they are brittle and their development is a long, effortful process. Few successful expert systems for real world problems have been demonstrated. In this paper, learning, the key to intelligent behavior and expertise, is described as the answer to both expert systems deficiencies. Machine learning techniques are described, with their applicability to expert systems. A framework to organize machine learning techniques is provided. The description is followed by examples taken from the structural design domain. AI / learning / expert systems / structures / techniques. 37. Requicha, Aristides A. G. 'Mathematical Models of Rigid Solid Objects -- Production Automation Project.' Rochester, NY: College of Engineering & Applied Science, University of Rochester, November, 1977. [3], 37 p. : ill.
summary	Computational models of solid objects are potentially useful in a variety of scientific and engineering fields, and in particular in the field of design and manufacturing automation for the mechanical industries. In recent years a multitude of modelling systems have been implemented both by research laboratories and commercial vendors, but little attention has been paid to the fundamental theoretical issues in geometric modelling. This has led to severe difficulties in assessing current and proposed systems, and in distinguishing essential capabilities and limitations from user conveniences and efficiency considerations. This paper seeks a sharp mathematical characterization of 'rigid solids' in a manner that is suitable for studies in design and production automation. It draws heavily on established results in modern geometry and topology. Relevant results scattered throughout the mathematical literature are placed in a coherent framework and presented in a form accessible to engineers and computer scientists. A companion paper is devoted to a discussion of representational issues in the context set forth by this paper
keywords	solid modeling, geometric modeling
series	CADline
last changed	1999/02/12 15:09

_id	c7e9
authors	Maver, T.W.
year	2002
title	Predicting the Past, Remembering the Future
source	SIGraDi 2002 - [Proceedings of the 6th Iberoamerican Congress of Digital Graphics] Caracas (Venezuela) 27-29 november 2002, pp. 2-3
summary	Charlas Magistrales 2There never has been such an exciting moment in time in the extraordinary 30 year history of our subject area, as NOW,when the philosophical theoretical and practical issues of virtuality are taking centre stage.The PastThere have, of course, been other defining moments during these exciting 30 years:• the first algorithms for generating building layouts (circa 1965).• the first use of Computer graphics for building appraisal (circa 1966).• the first integrated package for building performance appraisal (circa 1972).• the first computer generated perspective drawings (circa 1973).• the first robust drafting systems (circa 1975).• the first dynamic energy models (circa 1982).• the first photorealistic colour imaging (circa 1986).• the first animations (circa 1988)• the first multimedia systems (circa 1995), and• the first convincing demonstrations of virtual reality (circa 1996).Whereas the CAAD community has been hugely inventive in the development of ICT applications to building design, it hasbeen woefully remiss in its attempts to evaluate the contribution of those developments to the quality of the built environmentor to the efficiency of the design process. In the absence of any real evidence, one can only conjecture regarding the realbenefits which fall, it is suggested, under the following headings:• Verisimilitude: The extraordinary quality of still and animated images of the formal qualities of the interiors and exteriorsof individual buildings and of whole neighborhoods must surely give great comfort to practitioners and their clients thatwhat is intended, formally, is what will be delivered, i.e. WYSIWYG - what you see is what you get.• Sustainability: The power of «first-principle» models of the dynamic energetic behaviour of buildings in response tochanging diurnal and seasonal conditions has the potential to save millions of dollars and dramatically to reduce thedamaging environmental pollution created by badly designed and managed buildings.• Productivity: CAD is now a multi-billion dollar business which offers design decision support systems which operate,effectively, across continents, time-zones, professions and companies.• Communication: Multi-media technology - cheap to deliver but high in value - is changing the way in which we canexplain and understand the past and, envisage and anticipate the future; virtual past and virtual future!MacromyopiaThe late John Lansdown offered the view, in his wonderfully prophetic way, that ...”the future will be just like the past, onlymore so...”So what can we expect the extraordinary trajectory of our subject area to be?To have any chance of being accurate we have to have an understanding of the phenomenon of macromyopia: thephenomenon exhibitted by society of greatly exaggerating the immediate short-term impact of new technologies (particularlythe information technologies) but, more importantly, seriously underestimating their sustained long-term impacts - socially,economically and intellectually . Examples of flawed predictions regarding the the future application of information technologiesinclude:• The British Government in 1880 declined to support the idea of a national telephonic system, backed by the argumentthat there were sufficient small boys in the countryside to run with messages.• Alexander Bell was modest enough to say that: «I am not boasting or exaggerating but I believe, one day, there will bea telephone in every American city».• Tom Watson, in 1943 said: «I think there is a world market for about 5 computers».• In 1977, Ken Olssop of Digital said: «There is no reason for any individuals to have a computer in their home».The FutureJust as the ascent of woman/man-kind can be attributed to her/his capacity to discover amplifiers of the modest humancapability, so we shall discover how best to exploit our most important amplifier - that of the intellect. The more we know themore we can figure; the more we can figure the more we understand; the more we understand the more we can appraise;the more we can appraise the more we can decide; the more we can decide the more we can act; the more we can act themore we can shape; and the more we can shape, the better the chance that we can leave for future generations a trulysustainable built environment which is fit-for-purpose, cost-beneficial, environmentally friendly and culturally significactCentral to this aspiration will be our understanding of the relationship between real and virtual worlds and how to moveeffortlessly between them. We need to be able to design, from within the virtual world, environments which may be real ormay remain virtual or, perhaps, be part real and part virtual.What is certain is that the next 30 years will be every bit as exciting and challenging as the first 30 years.
series	SIGRADI
email
last changed	2016/03/10 09:55

_id	05f0
authors	Ball, A.A.
year	1977
title	CONSURF Part 3 : How the Program Is Used
source	computer Aided Design. January, 1977. vol. 9: pp. 9-12 : ill. includes bibliography
summary	This paper is the last of a series describing the surface lofting program CONSURF, and outlines how the program is used. The overall approach is geometrical and is modeled closely on manual lofting. The program user must have a practical understanding of shape and be able to visualize the surfaces he defines. He must also be numerate, but he does not need to understand the surface mathematics which is confined to the software. In this paper CONSURF, is considered as a production program and the contribution to the user are described
keywords	mechanical engineering, curved surfaces, lofting
series	CADline
last changed	2003/06/02 13:58

_id	ddssar0206
id	ddssar0206
authors	Bax, M.F.Th. and Trum, H.M.G.J.
year	2002
title	Faculties of Architecture
source	Timmermans, Harry (Ed.), Sixth Design and Decision Support Systems in Architecture and Urban Planning - Part one: Architecture Proceedings Avegoor, the Netherlands), 2002
summary	In order to be inscribed in the European Architect’s register the study program leading to the diploma ‘Architect’ has to meet the criteria of the EC Architect’s Directive (1985). The criteria are enumerated in 11 principles of Article 3 of the Directive. The Advisory Committee, established by the European Council got the task to examine such diplomas in the case some doubts are raised by other Member States. To carry out this task a matrix was designed, as an independent interpreting framework that mediates between the principles of Article 3 and the actual study program of a faculty. Such a tool was needed because of inconsistencies in the list of principles, differences between linguistic versions ofthe Directive, and quantification problems with time, devoted to the principles in the study programs. The core of the matrix, its headings, is a categorisation of the principles on a higher level of abstractionin the form of a taxonomy of domains and corresponding concepts. Filling in the matrix means that each study element of the study programs is analysed according to their content in terms of domains; thesummation of study time devoted to the various domains results in a so-called ‘profile of a faculty’. Judgement of that profile takes place by committee of peers. The domains of the taxonomy are intrinsically the same as the concepts and categories, needed for the description of an architectural design object: the faculties of architecture. This correspondence relates the taxonomy to the field of design theory and philosophy. The taxonomy is an application of Domain theory. This theory,developed by the authors since 1977, takes as a view that the architectural object only can be described fully as an integration of all types of domains. The theory supports the idea of a participatory andinterdisciplinary approach to design, which proved to be awarding both from a scientific and a social point of view. All types of domains have in common that they are measured in three dimensions: form, function and process, connecting the material aspects of the object with its social and proceduralaspects. In the taxonomy the function dimension is emphasised. It will be argued in the paper that the taxonomy is a categorisation following the pragmatistic philosophy of Charles Sanders Peirce. It will bedemonstrated as well that the taxonomy is easy to handle by giving examples of its application in various countries in the last 5 years. The taxonomy proved to be an adequate tool for judgement ofstudy programs and their subsequent improvement, as constituted by the faculties of a Faculty of Architecture. The matrix is described as the result of theoretical reflection and practical application of a matrix, already in use since 1995. The major improvement of the matrix is its direct connection with Peirce’s universal categories and the self-explanatory character of its structure. The connection with Peirce’s categories gave the matrix a more universal character, which enables application in other fieldswhere the term ‘architecture’ is used as a metaphor for artefacts.
series	DDSS
last changed	2003/11/21 15:16

_id	2168
authors	Bobrow, Daniel G. and Winograd, Terry
year	1977
title	An Overview of KRL, a Knowledge Representation Language
source	Cognitive Science. 1977. vol. 1: pp. 3-46. includes bibliography
summary	This paper describes KRL, a Knowledge Representation Language designed for use in understander systems. It outlines both the general concepts which underlie the research and the details of KRL-O, an experimental implementation of some of these concepts. KRL is an attempt to integrate procedural knowledge with a broad base of declarative forms. These forms provide a variety of ways to express the logical structure of the knowledge, in order to give flexibility in associating procedures (for memory and reasoning) with specific pieces of knowledge, and to control the relative accessibility of different facts and descriptions. The formalism for declarative knowledge is based on structured conceptual objects with associated descriptions. These objects form a network of memory units with several different sorts of linkages, each having well-specified implications for the retrieval process. Procedures can be associated directly with the internal structure of a conceptual object. This procedural attachment allows the steps for a particular operation to be determined by characteristics of the specific entities involved. The control structure of KRL is based on the belief that the next generation of intelligent programs will integrate data-directed and goal-directed processing by using multiprocessing. It provides for a priority-ordered multiprocess agenda with explicit (user-provided) strategies for scheduling and resource allocation. It provides procedure directories which operate along with process frameworks to allow procedural parametrization of the fundamental system processes for building, comparing, and retrieving memory structures. Future development of KRL will include integrating procedure definition with the descriptive formalism
keywords	knowledge, representation, languages, AI
series	CADline
last changed	2003/06/02 10:24

_id	sigradi2006_e028c
id	sigradi2006_e028c
authors	Griffith, Kenfield; Sass, Larry and Michaud, Dennis
year	2006
title	A strategy for complex-curved building design:Design structure with Bi-lateral contouring as integrally connected ribs
source	SIGraDi 2006 - [Proceedings of the 10th Iberoamerican Congress of Digital Graphics] Santiago de Chile - Chile 21-23 November 2006, pp. 465-469
summary	Shapes in designs created by architects such as Gehry Partners (Shelden, 2002), Foster and Partners, and Kohn Peterson and Fox rely on computational processes for rationalizing complex geometry for building construction. Rationalization is the reduction of a complete geometric shape into discrete components. Unfortunately, for many architects the rationalization is limited reducing solid models to surfaces or data on spread sheets for contractors to follow. Rationalized models produced by the firms listed above do not offer strategies for construction or digital fabrication. For the physical production of CAD description an alternative to the rationalized description is needed. This paper examines the coupling of digital rationalization and digital fabrication with physical mockups (Rich, 1989). Our aim is to explore complex relationships found in early and mid stage design phases when digital fabrication is used to produce design outcomes. Results of our investigation will aid architects and engineers in addressing the complications found in the translation of design models embedded with precision to constructible geometries. We present an algorithmically based approach to design rationalization that supports physical production as well as surface production of desktop models. Our approach is an alternative to conventional rapid prototyping that builds objects by assembly of laterally sliced contours from a solid model. We explored an improved product description for rapid manufacture as bilateral contouring for structure and panelling for strength (Kolarevic, 2003). Infrastructure typically found within aerospace, automotive, and shipbuilding industries, bilateral contouring is an organized matrix of horizontal and vertical interlocking ribs evenly distributed along a surface. These structures are monocoque and semi-monocoque assemblies composed of structural ribs and skinning attached by rivets and adhesives. Alternative, bi-lateral contouring discussed is an interlocking matrix of plywood strips having integral joinery for assembly. Unlike traditional methods of building representations through malleable materials for creating tangible objects (Friedman, 2002), this approach constructs with the implication for building life-size solutions. Three algorithms are presented as examples of rationalized design production with physical results. The first algorithm [Figure 1] deconstructs an initial 2D curved form into ribbed slices to be assembled through integral connections constructed as part of the rib solution. The second algorithm [Figure 2] deconstructs curved forms of greater complexity. The algorithm walks along the surface extracting surface information along horizontal and vertical axes saving surface information resulting in a ribbed structure of slight double curvature. The final algorithm [Figure 3] is expressed as plug-in software for Rhino that deconstructs a design to components for assembly as rib structures. The plug-in also translates geometries to a flatten position for 2D fabrication. The software demonstrates the full scope of the research exploration. Studies published by Dodgson argued that innovation technology (IvT) (Dodgson, Gann, Salter, 2004) helped in solving projects like the Guggenheim in Bilbao, the leaning Tower of Pisa in Italy, and the Millennium Bridge in London. Similarly, the method discussed in this paper will aid in solving physical production problems with complex building forms. References Bentley, P.J. (Ed.). Evolutionary Design by Computers. Morgan Kaufman Publishers Inc. San Francisco, CA, 1-73 Celani, G, (2004) “From simple to complex: using AutoCAD to build generative design systems” in: L. Caldas and J. Duarte (org.) Implementations issues in generative design systems. First Intl. Conference on Design Computing and Cognition, July 2004 Dodgson M, Gann D.M., Salter A, (2004), “Impact of Innovation Technology on Engineering Problem Solving: Lessons from High Profile Public Projects,” Industrial Dynamics, Innovation and Development, 2004 Dristas, (2004) “Design Operators.” Thesis. Massachusetts Institute of Technology, Cambridge, MA, 2004 Friedman, M, (2002), Gehry Talks: Architecture + Practice, Universe Publishing, New York, NY, 2002 Kolarevic, B, (2003), Architecture in the Digital Age: Design and Manufacturing, Spon Press, London, UK, 2003 Opas J, Bochnick H, Tuomi J, (1994), “Manufacturability Analysis as a Part of CAD/CAM Integration”, Intelligent Systems in Design and Manufacturing, 261-292 Rudolph S, Alber R, (2002), “An Evolutionary Approach to the Inverse Problem in Rule-Based Design Representations”, Artificial Intelligence in Design ’02, 329-350 Rich M, (1989), Digital Mockup, American Institute of Aeronautics and Astronautics, Reston, VA, 1989 Schön, D., The Reflective Practitioner: How Professional Think in Action. Basic Books. 1983 Shelden, D, (2003), “Digital Surface Representation and the Constructability of Gehry’s Architecture.” Diss. Massachusetts Institute of Technology, Cambridge, MA, 2003 Smithers T, Conkie A, Doheny J, Logan B, Millington K, (1989), “Design as Intelligent Behaviour: An AI in Design Thesis Programme”, Artificial Intelligence in Design, 293-334 Smithers T, (2002), “Synthesis in Designing”, Artificial Intelligence in Design ’02, 3-24 Stiny, G, (1977), “Ice-ray: a note on the generation of Chinese lattice designs” Environmental and Planning B, volume 4, pp. 89-98
keywords	Digital fabrication; bilateral contouring; integral connection; complex-curve
series	SIGRADI
email
last changed	2016/03/10 09:52

_id	19a8
authors	Schultz, Volkher
year	1999
title	A DIDACTIC CONCEPT FOR TRAINING ARCHITECTS AND INTERIOR DECORATORS
source	Full-scale Modeling and the Simulation of Light [Proceedings of the 7th European Full-scale Modeling Association Conference / ISBN 3-85437-167-5] Florence (Italy) 18-20 February 1999, pp. 29-39
summary	The 20th year anniversary of the Lichtlabor is used as an opportunity to look back. Two decades in a period of rapid technological development is a long time, during which furnishings pass or fail their trial period. The organizational structure of the Lichtlabor which includes lay-out and appliances has continually expanded since 1977 although the theoretical approach has not changed. Even the ideational structure of the Lichtlabor, without which an organizational structure would be worthless, has proved to be workable and effective as a didactic concept. This concept is based on the interdisciplinary midpoint between a technically (basic) understanding of light – a combination of abstract knowledge and experience gained – and its design-related application.
keywords	Lighting Laboratory, Interior Design, Didactic Concept, Visual Comfort, Architectural Space, Model Simulation, Real Environments
series	other
type	normal paper
more	http://info.tuwien.ac.at/efa
last changed	2004/05/04 11:28

_id	020d
authors	Shaviv, Edna
year	1986
title	Layout Design Problems: Systematic Approaches
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 28-52
summary	The complexity of the layout design problems known as the 'spatial allocation problems' gave rise to several approaches, which can be generally classified into two main streams. The first attempts to use the computer to generate solutions of the building layout, while in the second, computers are used only to evaluate manually generated solutions. In both classes the generation or evaluation of the layout are performed systematically. Computer algorithms for 'spatial allocation problems' first appeared more than twenty-five years ago (Koopmans, 1957). From 1957 to 1970 over thirty different programs were developed for generating the floor plan layout automatically, as is summarized in CAP-Computer Architecture Program, Vol. 2 (Stewart et al., 1970). It seems that any architect who entered the area of CAAD felt that it was his responsibility to find a solution to this prime architectural problem. Most of the programs were developed for batch processing, and were run on a mainframe without any sophisticated input/output devices. It is interesting to mention that, because of the lack of these sophisticated input/output devices, early researchers used the approach of automatic generation of optimal or quasioptimal layout solution under given constraints. Gradually, we find a recession and slowdown in the development of computer programs for generation of layout solutions. With the improvement of interactive input/output devices and user interfaces, the inclination today is to develop integrated systems in which the architectural solution is obtained manually by the architect and is introduced to the computer for the appraisal of the designer's layout solution (Maver, 1977). The manmachine integrative systems could work well, but it seems that in most of the integrated systems today, and in the commercial ones in particular, there is no route to any appraisal technique of the layout problem. Without any evaluation techniques in commercial integrated systems it seems that the geometrical database exists Just to create working drawings and sometimes also perspectives.
series	CAAD Futures
email
last changed	2003/05/16 20:58

_id	avocaad_2001_16
id	avocaad_2001_16
authors	Yu-Ying Chang, Yu-Tung Liu, Chien-Hui Wong
year	2001
title	Some Phenomena of Spatial Characteristics of Cyberspace
source	AVOCAAD - ADDED VALUE OF COMPUTER AIDED ARCHITECTURAL DESIGN, Nys Koenraad, Provoost Tom, Verbeke Johan, Verleye Johan (Eds.), (2001) Hogeschool voor Wetenschap en Kunst - Departement Architectuur Sint-Lucas, Campus Brussel, ISBN 80-76101-05-1
summary	"Space," which has long been an important concept in architecture (Bloomer & Moore, 1977; Mitchell, 1995, 1999), has attracted interest of researchers from various academic disciplines in recent years (Agnew, 1993; Benko & Strohmayer, 1996; Chang, 1999; Foucault, 1982; Gould, 1998). Researchers from disciplines such as anthropology, geography, sociology, philosophy, and linguistics regard it as the basis of the discussion of various theories in social sciences and humanities (Chen, 1999). On the other hand, since the invention of Internet, Internet users have been experiencing a new and magic "world." According to the definitions in traditional architecture theories, "space" is generated whenever people define a finite void by some physical elements (Zevi, 1985). However, although Internet is a virtual, immense, invisible and intangible world, navigating in it, we can still sense the very presence of ourselves and others in a wonderland. This sense could be testified by our naming of Internet as Cyberspace -- an exotic kind of space. Therefore, as people nowadays rely more and more on the Internet in their daily life, and as more and more architectural scholars and designers begin to invest their efforts in the design of virtual places online (e.g., Maher, 1999; Li & Maher, 2000), we cannot help but ask whether there are indeed sensible spaces in Internet. And if yes, these spaces exist in terms of what forms and created by what ways?To join the current interdisciplinary discussion on the issue of space, and to obtain new definition as well as insightful understanding of "space", this study explores the spatial phenomena in Internet. We hope that our findings would ultimately be also useful for contemporary architectural designers and scholars in their designs in the real world.As a preliminary exploration, the main objective of this study is to discover the elements involved in the creation/construction of Internet spaces and to examine the relationship between human participants and Internet spaces. In addition, this study also attempts to investigate whether participants from different academic disciplines define or experience Internet spaces in different ways, and to find what spatial elements of Internet they emphasize the most.In order to achieve a more comprehensive understanding of the spatial phenomena in Internet and to overcome the subjectivity of the members of the research team, the research design of this study was divided into two stages. At the first stage, we conducted literature review to study existing theories of space (which are based on observations and investigations of the physical world). At the second stage of this study, we recruited 8 Internet regular users to approach this topic from different point of views, and to see whether people with different academic training would define and experience Internet spaces differently.The results of this study reveal that the relationship between human participants and Internet spaces is different from that between human participants and physical spaces. In the physical world, physical elements of space must be established first; it then begins to be regarded as a place after interaction between/among human participants or interaction between human participants and the physical environment. In contrast, in Internet, a sense of place is first created through human interactions (or activities), Internet participants then begin to sense the existence of a space. Therefore, it seems that, among the many spatial elements of Internet we found, "interaction/reciprocity" Ñ either between/among human participants or between human participants and the computer interface Ð seems to be the most crucial element.In addition, another interesting result of this study is that verbal (linguistic) elements could provoke a sense of space in a degree higher than 2D visual representation and no less than 3D visual simulations. Nevertheless, verbal and 3D visual elements seem to work in different ways in terms of cognitive behaviors: Verbal elements provoke visual imagery and other sensory perceptions by "imagining" and then excite personal experiences of space; visual elements, on the other hand, provoke and excite visual experiences of space directly by "mapping".Finally, it was found that participants with different academic training did experience and define space differently. For example, when experiencing and analyzing Internet spaces, architecture designers, the creators of the physical world, emphasize the design of circulation and orientation, while participants with linguistics training focus more on subtle language usage. Visual designers tend to analyze the graphical elements of virtual spaces based on traditional painting theories; industrial designers, on the other hand, tend to treat these spaces as industrial products, emphasizing concept of user-center and the control of the computer interface.The findings of this study seem to add new information to our understanding of virtual space. It would be interesting for future studies to investigate how this information influences architectural designers in their real-world practices in this digital age. In addition, to obtain a fuller picture of Internet space, further research is needed to study the same issue by examining more Internet participants who have no formal linguistics and graphical training.
series	AVOCAAD
email
last changed	2005/09/09 10:48

_id	0319
authors	Stenros, Helmer
year	1993
title	The History of the Laboratory for Visual Simulation and Research Work in Tampere
source	Endoscopy as a Tool in Architecture [Proceedings of the 1st European Architectural Endoscopy Association Conference / ISBN 951-722-069-3] Tampere (Finland), 25-28 August 1993, pp. 3-8
summary	Many things are born from lucky chances or as the sum of them. I see it that way when I consider those events and stages that have led to this meeting in Tampere. For myself, the study of the environmental simulator and the activities around it started in Copenhagen in 1977 in the meeting of the professors of architecture of the northern countries. I met Professor Acking from Lund University of Technology and he told me about his studies in perception and the black–and–white environmental simulator that they had built. When we started architectural education in Tampere in 1969, I had from the beginning looked for new ways to teach in order to renew the old, traditional ways of teaching architecture. After the meeting in Copenhagen, we decided to build our own environmental simulator in our faculty in Tampere.
keywords	Architectural Endoscopy
series	EAEA
more	http://info.tuwien.ac.at/eaea/
last changed	2005/09/09 10:43

_id	ed51
authors	Bergeron, Philippe
year	1986
title	A General Version of Crow's Shadow Volumes
source	IEEE Computer Graphics and Applications September, 1986. vol. 6: pp. 17-28 : col. ill. includes bibliography.
summary	In 1977 Frank Crow introduced a new class of algorithms for the generation of shadows. His technique, based on the concept of shadow volumes, assumes a polygonal database and a constrained environment. For example, polyhedrons must be closed, and polygons must be planar. This article presents a new version of Crow's algorithm, developed at the Universite de Montreal, which attempts a less constrained environment. The method has allowed the handling of both open and closed models and nonplanar polygons with the viewpoint anywhere, including any shadow volume. It does not, however, sacrifice the essential features of Crow's original version: penetration between polygons is allowed, and any number of light sources can be defined anywhere in 3D space, including the view volume and any shadow volume. The method has been used successfully in the film Tony de Peltrie and is easily incorporated into an existing scan-line, hidden-surface algorithm
keywords	algorithms, shadowing, polygons, computer graphics
series	CADline
last changed	1999/02/12 15:07

_id	22ce
authors	Cahn, Deborah U., Johnston, Nancy E. and Johnston, William E.
year	1977
title	A Response to the 1977 GSPC Core Graphic System
source	SIGGRAPH '79 Conference Proceedings. August, 1979. vol. 13 ; no. 2: pp. 57-62. includes bibliography
summary	This paper responds to the 1977 Core Graphics System of SIGGRAPH's Graphics Standards Planning Committee (GSPC). The authors are interested in low-level device-independent graphics for applications doing data representation and annotation. The level structure and bias in the core system toward display list processor graphics are criticized. Specific issues discussed include display contexts, attributes, current position, 3-dimensional graphics, area filling, and graphics input
keywords	computer graphics, standards
series	CADline
last changed	2003/06/02 13:58

_id	490d
authors	De Groot, D.J.
year	1977
title	Designing Curved Surfaces with Analytical Functions
source	Computer Aided Design. January, 1977. vol. 9: pp. 3-8 : ill
summary	Shaping and computer-interactive design of curved surfaces of industrial objects, where artistic freedom is allowed for the outward appearance, is a time-consuming job particularly when feeding the computer program with the necessary geometrical input data. A design method is presented together with practical results of designed surfaces composed of simple analytical functions. Human input of geometrical and artistic data has been minimized. Smoothness and fairness are created by the surface composing functions
keywords	curved surfaces, representation, CAD, systems
series	CADline
last changed	2003/06/02 13:58

_id	76ce
authors	Grimson, W.
year	1985
title	Computational Experiments with a Feature Based Stereo Algorithm
source	IEEE Trans. Pattern Anal. Machine Intell., Vol. PAMI-7, No. 1
summary	Computational models of the human stereo system' can provide insight into general information processing constraints that apply to any stereo system, either artificial or biological. In 1977, Marr and Poggio proposed one such computational model, that was characterized as matching certain feature points in difference-of-Gaussian filtered images, and using the information obtained by matching coarser resolution representations to restrict the search'space for matching finer resolution representations. An implementation of the algorithm and'its testing on a range of images was reported in 1980. Since then a number of psychophysical experiments have suggested possible refinements to the model and modifications to the algorithm. As well, recent computational experiments applying the algorithm to a variety of natural images, especially aerial photographs, have led to a number of modifications. In this article, we present a version of the Marr-Poggio-Gfimson algorithm that embodies these modifications and illustrate its performance on a series of natural images.
series	journal paper
last changed	2003/04/23 15:14

_id	a4b7
authors	Lee, D. T. and Preparata, Franco P.
year	1977
title	Location of a Point in a Planar Subdivision and its Applications
source	SIAM Journal of Computing. September, 1977. vol. 6: pp. 594-606 : ill. includes bibliography
summary	Given a subdivision of the plane induced by a planar graph with n vertices, in this paper the problem of identifying which region of the subdivision contains a given test points is considered. A search algorithm, called point-location algorithm, which operates on a suitably preprocessed data structure is presented. The search runs in time at most O((log n)2), while the preprocessing task runs in time at most O(n log n) and requires O(n) storage. The methods are quite general, since an arbitrary subdivision can be transformed in time at most O(n log n) into one to which the preprocessing procedure is applicable. This solution of the point location problem yields interesting and efficient solutions of other geometric problems, such as spatial convex inclusion and inclusion in an arbitrary polygon
keywords	computational geometry, algorithms, analysis, graphs, point inclusion
series	CADline
last changed	2003/06/02 13:58

_id	ddss2006-hb-187
id	DDSS2006-HB-187
authors	Lidia Diappi and Paola Bolchi
year	2006
title	Gentrification Waves in the Inner-City of Milan - A multi agent / cellular automata model based on Smith's Rent Gap theory
source	Van Leeuwen, J.P. and H.J.P. Timmermans (eds.) 2006, Innovations in Design & Decision Support Systems in Architecture and Urban Planning, Dordrecht: Springer, ISBN-10: 1-4020-5059-3, ISBN-13: 978-1-4020-5059-6, p. 187-201
summary	The aim of this paper is to investigate the gentrification process by applying an urban spatial model of gentrification, based on Smith's (1979; 1987; 1996) Rent Gap theory. The rich sociological literature on the topic mainly assumes gentrification to be a cultural phenomenon, namely the result of a demand pressure of the suburban middle and upper class, willing to return to the city (Ley, 1980; Lipton, 1977, May, 1996). Little attempt has been made to investigate and build a sound economic explanation on the causes of the process. The Rent Gap theory (RGT) of Neil Smith still represents an important contribution in this direction. At the heart of Smith's argument there is the assumption that gentrification takes place because capitals return to the inner city, creating opportunities for residential relocation and profit. This paper illustrates a dynamic model of Smith's theory through a multi-agent/ cellular automata system approach (Batty, 2005) developed on a Netlogo platform. A set of behavioural rules for each agent involved (homeowner, landlord, tenant and developer, and the passive 'dwelling' agent with their rent and level of decay) are formalised. The simulations show the surge of neighbouring degradation or renovation and population turn over, starting with different initial states of decay and estate rent values. Consistent with a Self Organized Criticality approach, the model shows that non linear interactions at local level may produce different configurations of the system at macro level. This paper represents a further development of a previous version of the model (Diappi, Bolchi, 2005). The model proposed here includes some more realistic factors inspired by the features of housing market dynamics in the city of Milan. It includes the shape of the potential rent according to city form and functions, the subdivision in areal submarkets according to the current rents, and their maintenance levels. The model has a more realistic visualisation of the city and its form, and is able to show the different dynamics of the emergent neighbourhoods in the last ten years in Milan.
keywords	Multi agent systems, Housing market, Gentrification, Emergent systems
series	DDSS
last changed	2006/08/29 12:55

_id	3105
authors	Novak, T.P., Hoffman, D.L., and Yung, Y.-F.
year	1996
title	Modeling the structure of the flow experience
source	INFORMS Marketing Science and the Internet Mini-Conference, MIT
summary	The flow construct (Csikszentmihalyi 1977) has recently been proposed by Hoffman and Novak (1996) as essential to understanding consumer navigation behavior in online environments such as the World Wide Web. Previous researchers (e.g. Csikszentmihalyi 1990; Ghani, Supnick and Rooney 1991; Trevino and Webster 1992; Webster, Trevino and Ryan 1993) have noted that flow is a useful construct for describing more general human-computer interactions. Hoffman and Novak define flow as the state occurring during network navigation which is: 1) characterized by a seamless sequence of responses facilitated by machine interactivity, 2) intrinsically enjoyable, 3) accompanied by a loss of self-consciousness, and 4) selfreinforcing." To experience flow while engaged in an activity, consumers must perceive a balance between their skills and the challenges of the activity, and both their skills and challenges must be above a critical threshold. Hoffman and Novak (1996) propose that flow has a number of positive consequences from a marketing perspective, including increased consumer learning, exploratory behavior, and positive affect."
series	other
last changed	2003/04/23 15:50

_id	ecec
authors	Requicha, Aristides A.G. and Voelcker, H.B.
year	1977
title	Constructive Solid Geometry
source	November, 1977. [3] 36 p. : ill. includes bibliography: p. 31-33
summary	The term 'constructive solid geometry' denotes a class of schemes for describing solid objects as compositions (usually 'additions' and 'subtractions') of primitive solid 'building blocks.' The notion of adding and subtracting solids has been used by mechanical designers and others for generations, but attempts to embody it in computer-based modelling systems have been hindered by the absence of a firm mathematical foundation. This paper provides such a foundation by drawing on established results in modern axiomatic geometry and point set topology. The paper also initiates a broader discussion, to be continued in subsequent papers, of three seminal topics: mathematical modelling of solids, representation of solids, and calculation of geometrical properties of solids
keywords	solid modeling, computational geometry, geometric modeling, CSG, topology, mathematics, representation
series	CADline
last changed	2003/06/02 13:58

_id	avocaad_2001_09
id	avocaad_2001_09
authors	Yu-Tung Liu, Yung-Ching Yeh, Sheng-Cheng Shih
year	2001
title	Digital Architecture in CAD studio and Internet-based competition
source	AVOCAAD - ADDED VALUE OF COMPUTER AIDED ARCHITECTURAL DESIGN, Nys Koenraad, Provoost Tom, Verbeke Johan, Verleye Johan (Eds.), (2001) Hogeschool voor Wetenschap en Kunst - Departement Architectuur Sint-Lucas, Campus Brussel, ISBN 80-76101-05-1
summary	Architectural design has been changing because of the vast and creative use of computer in different ways. From the viewpoint of designing itself, computer has been used as drawing tools in the latter phase of design (Mitchell 1977; Coyne et al. 1990), presentation and simulation tools in the middle phase (Liu and Bai 2000), and even critical media which triggers creative thinking in the very early phase (Maher et al. 2000; Liu 1999; Won 1999). All the various roles that computer can play have been adopted in a number of professional design corporations and so-called computer-aided design (CAD) studio in schools worldwide (Kvan 1997, 2000; Cheng 1998). The processes and outcomes of design have been continuously developing to capture the movement of the computer age. However, from the viewpoint of social-cultural theories of architecture, the evolvement of design cannot be achieved solely by designers or design processes. Any new idea of design can be accepted socially, culturally and historically only under one condition: The design outcomes could be reviewed and appreciated by critics in the field at the time of its production (Csikszentmihalyi 1986, 1988; Schon and Wiggins 1992; Liu 2000). In other words, aspects of design production (by designers in different design processes) are as critical as those of design appreciation (by critics in different review processes) in the observation of the future trends of architecture.Nevertheless, in the field of architectural design with computer and Internet, that is, so-called computer-aided design computer-mediated design, or internet-based design, most existing studies pay more attentions to producing design in design processes as mentioned above. Relatively few studies focus on how critics act and how they interact with designers in the review processes. Therefore, this study intends to investigate some evolving phenomena of the interaction between design production and appreciation in the environment of computer and Internet.This paper takes a CAD studio and an Internet-based competition as examples. The CAD studio includes 7 master's students and 2 critics, all from the same countries. The Internet-based competition, held in year 2000, includes 206 designers from 43 counties and 26 critics from 11 countries. 3 students and the 2 critics in the CAD studio are the competition participating designers and critics respectively. The methodological steps are as follows: 1. A qualitative analysis: observation and interview of the 3 participants and 2 reviewers who join both the CAD studio and the competition. The 4 analytical criteria are the kinds of presenting media, the kinds of supportive media (such as verbal and gesture/facial data), stages of the review processes, and interaction between the designer and critics. The behavioral data are acquired by recording the design presentation and dialogue within 3 months. 2. A quantitative analysis: statistical analysis of the detailed reviewing data in the CAD studio and the competition. The four 4 analytical factors are the reviewing time, the number of reviewing of the same project, the comparison between different projects, and grades/comments. 3. Both the qualitative and quantitative data are cross analyzed and discussed, based on the theories of design thinking, design production/appreciation, and the appreciative system (Goodman 1978, 1984).The result of this study indicates that the interaction between design production and appreciation during the review processes could differ significantly. The review processes could be either linear or cyclic due to the influences from the kinds of media, the environmental discrepancies between studio and Internet, as well as cognitive thinking/memory capacity. The design production and appreciation seem to be more linear in CAD studio whereas more cyclic in the Internet environment. This distinction coincides with the complementary observations of designing as a linear process (Jones 1970; Simon 1981) or a cyclic movement (Schon and Wiggins 1992). Some phenomena during the two processes are also illustrated in detail in this paper.This study is merely a starting point of the research in design production and appreciation in the computer and network age. The future direction of investigation is to establish a theoretical model for the interaction between design production and appreciation based on current findings. The model is expected to conduct using revised protocol analysis and interviews. The other future research is to explore how design computing creativity emerge from the process of producing and appreciating.
series	AVOCAAD
email
last changed	2005/09/09 10:48

_id	ecaade2007_042
id	ecaade2007_042
authors	Ozel, Filiz
year	2007
title	Pattern Language and Embedded Knowledge in Building Information Modeling
source	Predicting the Future [25th eCAADe Conference Proceedings / ISBN 978-0-9541183-6-5] Frankfurt am Main (Germany) 26-29 September 2007, pp. 457-464
doi	https://doi.org/10.52842/conf.ecaade.2007.457
summary	When Christopher Alexander (1977), trained both as a mathematician and an architect, published his seminal work “The Pattern Language” in the 1970’s and introduced the concept of “pattern language”, computers were still in their infancy, CAD did not exist as we know it today, and computer information modeling was not even in the radar screen of researchers. Design communication simply meant manual drafting. With the concept of ‘pattern language” (http://www.patternlanguage.com/), Alexander proposed a systematic method for dealing with complexity, which proved itself to be more relevant than ever in the digital age. The concept is often cited by computer scientists as a precursor to object oriented modeling. This study explores the potential of “pattern language” for structuring building information and design knowledge within the framework of the recent developments in building information modeling (BIM). In this article, comparisons to the approach taken by the software engineering industry who embraced the idea of “patterns” as a systematic way to software development are also made. While Alexander’s pattern language proposes a method with which the designer can incorporate his/her experiences and design vision systematically into the process of designing, software industry’s approach to patterns describes a method for providing problem and solution patterns (i.e. prototypes) that can be used repeatedly during software development. There is obviously a significant difference between the original intent of the “pattern language” and the way it was later used in other fields including software engineering and business solutions. At the cross section of architectural design and software engineering, Building Information Modeling (BIM) software can benefit from carefully incorporating a combination of these two approaches into its structure as patterns.
keywords	Building information modeling, Christopher Alexander, pattern language, software development
series	eCAADe
email
last changed	2022/06/07 08:00

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