Cumincad : CUMINCAD Papers : Search Results

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	6094
authors	Blinn, J.I.
year	1982
title	A Generalization of Algebraic Surface Drawing
source	ACM Transaction on Graphics, vol. 1, no. 3, pp. 235-256, 1982
summary	The technology of creating realistic and visually interesting images of three- dimensional shapes is advancing on many fronts. One such front is the develop- ment of algorithms for drawing curved surfaces directly from their mathematical definitions rather than by dividing them into large numbers of polygons. Two classes of surfaces which have received attention are the quadric and the bivariate parametric surfaces. Bivariate parametric surfaces are generated by three func- tions of two variables (most popularly polynomials), as the variables take on different values. Algorithms dealing with such surfaces are due to Catmull; Lane, Carpenter, Whitted and Blinn; and Clark.
series	journal paper
last changed	2003/11/21 15:16

_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	66df
authors	Cendes, Z.J., Minhas, F.U. and Silvester, P.P.
year	1982
title	Universal Finite Element Matrices for Tetrahedra
source	45, [22] p Pittsburgh: Design Research Center, CMU, December, 1982. DRC- 18-58-82. includes bibliography.
summary	Methods are described for forming finite element matrices for a wide variety of operators on tetrahedral finite elements, in a manner similar to that previously employed for line segments and triangles. This technique models the differentiation and product-embedding operators as rectangular matrices, and produces finite element matrices by replacing all required analytic operations by their finite matrix analogues. The method is illustrated by deriving the conventional matrix representation for Laplace's equation. Brief computer programs are given, which generate universal finite element matrices for use in various applications
keywords	mathematics, computational geometry, finite elements, analysis
series	CADline
last changed	2003/06/02 13:58

_id	adcd
authors	Cohen, Paol R. and Feigenbaum, Edward A. (editors)
year	1982
title	The Handbook of Artificial Intelligence
source	xviii, 639 p. Stanford, California: HeurisTech Press, 1982. vol. 3: See The Handbook of Artificial intelligence edited by Avron, Barr and Feigenbaum, Edward. Includes bibliography p. 565-586 and cumulative indexes
summary	Part of three volumes, this volume contains chapters on models of cognition, automatic deduction, vision, learning and planning
keywords	AI, deduction, learning, cognition, planning
series	CADline
last changed	2003/06/02 13:58

_id	e5c4
authors	Johnson-Laird
year	1983
title	Mental Models
source	Cambridge, MA: Harvard University Press
summary	As psychological representations of real, hypothetical, or imaginary situations, mental models were first postulated by the Scottish psychologist Kenneth Craik (1943), who wrote that the mind constructs "small-scale models" of reality to anticipate events, to reason, and to underlie . The models are constructed in working memory as a result of perception, the comprehension of discourse, or imagination (see 1982; Johnson-Laird 1983). A crucial feature is that their structure corresponds to the structure of what they represent. Mental models are accordingly akin to architects' models of buildings and to chemists' models of complex molecules.
series	other
last changed	2003/04/23 15:50

_id	4eb7
authors	Kirsch, Uri
year	1982
title	Optimal Design of Continuous Prestressed Concrete Structures
source	25 p. : il. tables Pittsburgh, PA: Design Research Center, CMU, December, 1982. DRC-12-11-82. includes bibliography: p. 20-21
summary	Optimal design of continuous prestressed systems is stated in a nonlinear programming form. The design variables are the concrete dimensions, tendon coordinates, and prestressing force. The constraints are related to various behavior and design requirements and the objective function represents the overall cost. Some simplified models, intended to improve the solution efficiency, are presented. These include: explicit formulations of the general problem and the problem of minimizing the concrete dimensions; linear programming formulation of the tendon configuration and prestressing force optimization; and direct determination of the prestressing force for given concrete dimensions and tendon coordinates. Some examples illustrate the various problem formulations and solution methodology
keywords	engineering, structures, optimization, linear programming
series	CADline
last changed	1999/02/12 15:08

_id	c6e3
authors	Kirsch, Uri
year	1982
title	Approximation Concepts for Optimum Structural Design
source	25 p. Pittsburgh, PA: Design Research Center, CMU, December, 1982. DRC-12-12-82. includes bibliography
summary	When elastic behavior is assumed, the optimum structural design problem is stated in an implicit nonlinear programming form. Approximate behavior models are introduced to obtain explicit constraint functions, essential in many practical design problems. For the displacement analysis formulation, some possible explicit approximations of the nodal displacements in terms of the design variables are reviewed. It is shown that any approximation of the displacements will lead to a solution which does not necessarily satisfy equilibrium. Methods for solving the approximate problem are discussed. Using the force analysis formulation, it is shown that explicit approximations of the redundant forces will lead to solutions which do not necessarily satisfy compatibility. Some simplified models of the explicit problem are presented and solution methods are discussed
keywords	structures, design, engineering, optimization, civil engineering, approximation
series	CADline
last changed	1999/02/12 15:08

_id	c361
authors	Logan, Brian S.
year	1986
title	Representing the Structure of Design Problems
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 158-170
summary	In recent years several experimental CAD systems have emerged which, focus specifically on the structure of design problems rather than on solution generation or appraisal (Sussman and Steele, 1980; McCallum, 1982). However, the development of these systems has been hampered by the lack of an adequate theoretical basis. There is little or no argument as to what the statements comprising these models actually mean, or on the types of operations that should be provided. This chapter describes an attempt to develop a semantically adequate basis for a model of the structure of design problems and presents a representation of this model in formal logic.
series	CAAD Futures
last changed	1999/04/03 17:58

_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	e55f
authors	Newell, Allen and Rosenbloom, Paul S.
year	1982
title	Mechanisms of Skill Acquisition and the Law of Practice
source	[2], III, 52 p. : ill Design Research Center, CMU, April, 1982. DRC-15-16-82. includes bibliography.
summary	Practice, and the performance improvement that it engenders, has long been a major topic in psychology. In this paper, both experimental and theoretical approaches are employed in an investigation of the mechanisms underlying this improvement. On the experimental side, it is argued that a single law, the power of law of practice, adequately describes all of the practice data. On the theoretical side, a model of practice rooted in modern cognitive psychology, the chunking theory of learning, is formulated. The paper consists of (1) the presentation of a set of empirical practice curves; (2) mathematical investigations into the nature of power law functions; (3) evaluations of the ability of three different classes of functions to adequately model the empirical curves; (4) a discussion of the existing models of practice; (5) a presentation of the chunking theory of learning
keywords	problem solving, learning, psychology, knowledge acquisition, practice, expert, representation
series	CADline
last changed	2003/06/02 13:58

_id	4bae
authors	Rasdorf, William J. and Kutay, Ali R.
year	1982
title	Maintenance of Integrity During Concurrent Access in a Building Design Database
source	Computer Aided Design. Butterworth Scientific Ltd., July, 1982. vol. 14: pp. 201-207. includes bibliography
summary	This paper proposes a building design database model that insures database integrity in a highly flexible relational structure while supporting disciplinary and interdisciplinary concurrent use. The model strongly supports designer-database interaction by providing extremely versatile data access mechanisms and an associated concurrency control mechanism. Building design components are represented in terms of their location, their attribute values, and combinations of the two. Both the logical and physical database models are illustrated. The relational model is vital for achieving the greatest flexibility in representing and accessing building design data. Its standard relations are ideal for information representation. In addition, the operators provided by the model enable the engineer to readily restructure the database to support building design needs. This paper introduces a database structuring mechanism referred to as catalogs. Catalogs provide a highly versatile mechanism for accessing database information by grouping building components into data units called modules. The modules provide convenient access to multiple design entities. Also included is a protection relation that provides a concurrency control environment for the catalog relations. The module concept is particularly important in design because it enables the ad hoc groupings of data which are so often necessary to support the design process. The module is recommended as the level to which a locking concurrency control mechanism be applied. It is a small enough data unit to support concurrency for interdisciplinary design activities, yet not so small as to require extensive overhead in the concurrency control implementation. Two different modes of locking are recommended for the catalog relations of a building design database to achieve maximum concurrency and efficiency of access by designers
keywords	database, concurrency, access, constraints management
series	CADline
last changed	2003/06/02 13:58

_id	452c
authors	Vanier, D. J. and Worling, Jamie
year	1986
title	Three-dimensional Visualization: A Case Study
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 92-102
summary	Three-dimensional computer visualization has intrigued both building designers and computer scientists for decades. Research and conference papers present an extensive list of existing and potential uses for threedimensional geometric data for the building industry (Baer et al., 1979). Early studies on visualization include urban planning (Rogers, 1980), treeshading simulation (Schiler and Greenberg, 1980), sun studies (Anon, 1984), finite element analysis (Proulx, 1983), and facade texture rendering (Nizzolese, 1980). With the advent of better interfaces, faster computer processing speeds and better application packages, there had been interest on the part of both researchers and practitioners in three-dimensional -models for energy analysis (Pittman and Greenberg, 1980), modelling with transparencies (Hebert, 1982), super-realistic rendering (Greenberg, 1984), visual impact (Bridges, 1983), interference clash checking (Trickett, 1980), and complex object visualization (Haward, 1984). The Division of Building Research is currently investigating the application of geometric modelling in the building delivery process using sophisticated software (Evans, 1985). The first stage of the project (Vanier, 1985), a feasibility study, deals with the aesthetics of the mode. It identifies two significant requirements for geometric modelling systems: the need for a comprehensive data structure and the requirement for realistic accuracies and tolerances. This chapter presents the results of the second phase of this geometric modelling project, which is the construction of 'working' and 'presentation' models for a building.
series	CAAD Futures
email
last changed	2003/05/16 20:58

_id	2786
authors	Woodwark, J.R.
year	1989
title	Splitting Set-Theoretic Solid Models into Connected Components
source	10 p. : ill. Winchester: IBM UK Scientific Center, IBM United Kingdom Laboratories Limited, June, 1989. IBM UKSC 210. includes bibliography In general, there is no way to tell how many pieces (connected components) a set-theoretic (CSG) solid model represents, except via conversion to a boundary model. Recent work on the elimination of redundant primitives has been linked with techniques for identifying connected components in quad-trees and oct-trees into a strategy to attack this problem. Some success has been achieved, and an experimental Prolog program, working in two dimensions, that finds connected components and determines the set-theoretic representation of each component, is reported, and further developments proposed. CSG / quadtree / octree / primitives / algorithms. 43. Woodwark, J. R. and Quinlan K. M. 'Reducing the Effect of Complexity on Volume Model Evaluation.' Computer Aided Design. April, 1982. pp. 89-95 : ill. includes bibliography.
summary	A major problem with volume modelling systems is that processing times may increase with model complexity in a worse than linear fashion. The authors have addressed this problem, for picture generation, by repeatedly dividing the space occupied by a model, and evaluating the sub-models created only when they meet a criterion of simplicity. Hidden surface elimination has been integrated with evaluation, in such a way that major portions of the model which are not visible are never evaluated. An example demonstrates a better than linear relationship between model complexity and computation time, and also shows the effect of picture complexity on the performance of the process
keywords	CAD, computational geometry, solid modeling, geometric modeling, algorithms, hidden surfaces, CSG
series	CADline
last changed	2003/06/02 13:58

_id	0107
authors	Akin, Omer and Weinel, Eleanor F. (editors)
year	1982
title	Representation and Architecture
source	v, 285 p. : ill. Silver Spring, Maryland: Information Dynamics, Inc., 1982
summary	A collection of papers developed from the proceeding of the Northeastern Regional meeting of the Association of Collegiate Schools of Architecture (ACSA), held at the Department of Architecture, Carnegie Mellon University. The introduction includes articles about representation, representation and architecture. Part 1, Who/To Whom speaks about representation and participatory design process, and of a system for recording behavior and occupying of design. Part 2, How: includes Figure, System and Memory, the Process of Design ; Representation and Creativity in Architecture and Miniature Substitutes. Part 3, With What :Information and Data Base in Design : the Computer as a Design Medium, Slides Talk and Translation
keywords	design process, representation, architecture, creativity
series	CADline
email
last changed	2003/05/17 10:09

_id	8a88
authors	Anderson, David P.
year	1982
title	Hidden Line Elimination in Projected Grid Surfaces
source	ACM Transactions on Graphics. October, 1982. vol. 1: pp. 274-288 : ill. includes a short bibliography
summary	The hidden line and hidden surface problems are simpler when restricted to special classes of objects. An example is the class of grid surfaces, that is, graphs of bivariate functions represented by their values on a set of grid points. Projected grid surfaces have geometric properties which permit hidden line or hidden surface elimination to be done more easily than in the general case. These properties are discussed in this paper, and an algorithm is given which exploits them
keywords	algorithms, hidden lines, hidden surfaces, grids, computer graphics
series	CADline
last changed	2003/06/02 10:24

_id	843d
authors	Avron, Barr and Feigenbaum, Edward A. (editors)
year	1982
title	The Handbook of Artificial Intelligence
source	xiii, 428 p. Stanford, California: Heuristech Press, 1982. vol. 2 of 3: Includes bibliography p.383-402 and indexes
summary	Part 2 of a three vol. work. This vol covers: AI programming languages, the kinds of programming languages suitable for AI, features and environments developed that were developed for its purpose. Expert systems in science, medicine and education. The last chapters reviews automatic programming
keywords	AI, programming, languages, expert systems, automation
series	CADline
last changed	2003/06/02 13:58

_id	4763
authors	Balas, Egon
year	1982
title	Integer Programming
source	December, 1982. 32 p
summary	Includes bibliography. This is an introductory survey of integer programming, its theory, methodology and applications, for the Encyclopedia of Statistical Sciences
keywords	integer programming, operations research
series	CADline
last changed	1999/02/12 15:07

_id	2045
authors	Balas, Egon
year	1982
title	A Class of Location, Distribution and Scheduling Problems : Modeling and Solution Methods
source	21 p., 8 + 4 p. of appendix : ill. Carnegie Mellon University, Pittsburgh, PA: Design Research Center, December, 1982. includes bibliography
summary	Discusses the potential of set covering techniques. Illustrates problem formulation techniques on several important classes of real-world problems. Also describes a class of algorithms for solving set covering problems, based on cutting planes, heuristics and subgradient optimization
keywords	problem solving, methods, algorithms, problem definition, modeling, optimization, operations research
series	CADline
last changed	1999/02/12 15:07

_id	a426
authors	Barsky, Brian A. and Greenberg, Donald P.
year	1982
title	Interactive Surface Representation System Using a B-spline Formulation with Interpolation Capability
source	computer Aided Design. July, 1982. vol. 14: pp. 187-194 : col.ill. includes bibliography
summary	An interactive surface representation system is described which uses a parametric uniform bicubic B-spline formulation which can describe a surface initially defined to interpolate a specified network of points
keywords	CAD, curved surfaces, computational geometry, interpolation, B-splines
series	CADline
last changed	2003/06/02 13:58

_id	898a
authors	Bay, J.H.
year	2002
title	Cognitive Biases and Precedent Knowledge in Human and Computer-Aided Design Thinking
doi	https://doi.org/10.52842/conf.caadria.2002.213
source	CAADRIA 2002 [Proceedings of the 7th International Conference on Computer Aided Architectural Design Research in Asia / ISBN 983-2473-42-X] Cyberjaya (Malaysia) 18–20 April 2002, pp. 213-220
summary	Cognitive biases (illusions) and potential errors can occur when using precedent knowledge for analogical, pre-parametric and qualitative design thinking. This paper refers largely to part of a completed research (Bay 2001) on how heuristic biases, discussed by Tversky and Kahneman (1982) in cognitive psychology, can affect judgement and learning of facts from precedents in architectural design, made explicit using a kernel of conceptual system (Tzonis et. al., 1978) and a framework of architectural representation (Tzonis 1992). These are used here to consider how such illusions and errors may be transferred to computer aided design thinking.
series	CAADRIA
email
last changed	2022/06/07 07:54

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