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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	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	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	8c27
authors	Kalay, Yehuda E.
year	1982
title	Determining the Spatial Containment of a Point in General Polyhedra
source	Computer graphics and Image Processing. 1982. vol. 19: pp. 303-334 : ill. includes bibliography. See also criticism and improvements in Orlowski, Marian
summary	Determining the inclusion of a point in volume-enclosing polyhedra (shapes) in 3D space is, in principle, the extension of the well-known problem of determining the inclusion of a point in a polygon in 2D space. However, the extra degree of freedom makes 3D point-polyhedron containment analysis much more difficult to solve than the 2D point polygon problem, mainly because of the nonsequential ordering of the shape elements, which requires global shape data to be applied for resolving special cases. Two general O(n) algorithms for solving the problem by reducing the 3D case into the solvable 2D case are presented. The first algorithm, denoted 'the projection method,' is applicable to any planar- faced polyhedron, reducing the dimensionality by employing parallel projection to generate planar images of the shape faces, together with an image of the point being tested for inclusion. The containment relationship of these images is used to increment a global parity-counter when appropriate, representing an abstraction for counting the intersections between the surface of the shape and a halfline extending from the point to infinity. An 'inside' relationship is established when the parity-count is odd. Special cases (coincidence of the halfline with edges or vertices of the shape) are resolved by eliminating the coincidental elements and re-projecting the merged faces. The second algorithm, denoted 'the intersection method,' is applicable to any well- formed shape, including curved-surfaced ones. It reduces the dimensionality by intersecting the polygonal trace of the shape surface at the plane of intersection, which is tested for containing the trace of the point in the plane, directly establishing the overall 3D containment relationship. A particular O(n) implementation of the 2D point-in-polygon inclusion algorithm, which is used for solving the problem once reduced in dimensionality, is also presented. The presentation is complemented by discussions of the problems associated with point-polyhedron relationship determination in general, and comparative analysis of the two particular algorithms presented
keywords	geometric modeling, point inclusion, polygons, polyhedra, computational geometry, algorithms, search, B-rep
series	CADline
email
last changed	2003/06/02 10:24

_id	2415
authors	Nievergelt, J. and Preparata, Franco P.
year	1982
title	Plane-Sweep Algorithms for Intersecting Geometric Figures
source	Communications of the ACM. October, 1982. vol. 25: pp. 739-747 : ill. includes bibliography
summary	Algorithms in computational geometry are of increasing importance in computer-aided design, for example, in the layout of integrated circuits. The efficient computation of the intersection of several superimposed figures is a basic problem. Plane figures defined by points connected by straight line segments are considered, for example, polygons (not necessarily simple) and maps (embedded planar graphs). The regions into which the plane is partitioned by these intersecting figures are to be processed in various ways such as listing the boundary of each region in cyclic order or sweeping the interior of each region. Let m be the total number of points of all the figures involved and s be the total number of intersections of all line segments. A two plane-sweep algorithm that solves the problems above is presented; in the general case (non convexity) in time O((n+s)log-n) and space O(n+s); when the regions of each given figure are convex, the same can be achieved in time O(n log n +s) and space O(n)
keywords	computational geometry, algorithms, intersection, mapping, polygons, data structures, analysis
series	CADline
last changed	2003/06/02 10:24

_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	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	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	1b10
id	1b10
authors	Bay, Joo-Hwa
year	2001
title	Cognitive Biases - The case of tropical architecture
source	Delft University of Technology
summary	This dissertation investigates, i) How cognitive biases (or illusions) may lead to errors in design thinking, ii) Why architects use architectural precedents as heuristics despite such possible errors, and iii) Develops a design tool that can overcome this type of errors through the introduction of a rebuttal mechanism. The mechanism controls biases and improves accuracy in architectural thinking. // The research method applied is interdisciplinary. It employs knowledge from cognitive science, environmental engineering, and architectural theory. The case study approach is also used. The investigation is made in the case of tropical architecture. The investigation of architectural biases draws from work by A. Tversky and D. Kahneman in 1982 on “Heuristics and biases”. According to Tversky and Kahneman, the use of heuristics of representativeness (based on similarity) and availability (based on ease of recall and imaginability) for judgement of probability can result in cognitive biases of illusions of validity and biases due to imaginability respectively. This theory can be used analogically to understand how errors arise in the judgement of environmental behaviour anticipated from various spatial configurations, leading to designs with dysfunctional performances when built. Incomplete information, limited time, and human mental resources make design thinking in practice difficult and impossible to solve. It is not possible to analyse all possible alternative solutions, multiple contingencies, and multiple conflicting demands, as doing so will lead to combinatorial explosion. One of the ways to cope with the difficult design problem is to use precedents as heuristic devices, as shortcuts in design thinking, and at the risk of errors. This is done with analogical, pre-parametric, and qualitative means of thinking, without quantitative calculations. Heuristics can be efficient and reasonably effective, but may not always be good enough or even correct, because they can have associated cognitive biases that lead to errors. Several debiasing strategies are discussed, and one possibility is to introduce a rebuttal mechanism to refocus the designer’s thinking on the negative and opposite outcomes in his judgements, in order to debias these illusions. The research is carried out within the framework of design theory developed by the Design Knowledge System Research Centre, TUDelft. This strategy is tested with an experiment. The results show that the introduction of a rebuttal mechanism can debias and improve design judgements substantially in environmental control. The tool developed has possible applications in design practice and education, and in particular, in the designing of sustainable environments.
keywords	Design bias; Design knowledge; Design rebuttal; Design Precedent; Pre-parametric design; Tropical architecture; Sustainability
series	thesis:PhD
type	normal paper
email
last changed	2006/05/28 07:42

_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	482a
authors	Cole, Sam
year	1982
title	A Microprocessor Revolution and the World Distribution of Income: A General Equilibrium Approach
source	International Political Science Review. 1982. vol.3: pp. 434- 454 ; ill. includes bibliography
summary	This article shows that even if the world economy is able to withstand and surmount the present world crisis, the combination of market forces and rapid technical change that would be the result of a microprocessor revolution will give rise to large shifts in the distribution of income within and between both rich and poor countries. Some developed and developing economies may be unable to join the move to new technologies. In a world governed by only economic forces, all countries, whether they choose to adopt new systems of production or not, will be affected. Indeed, whatever their degree of involvement, all countries are beginning to feel in varying degrees the chain reaction that reverberates through and between all sectors of their domestic and the world economies. To gain insights into interrelations between technological change and global markets, this article uses a special type of model -- a general equilibrium model -- that enables the study to focus on exactly these variables
keywords	technology, economics
series	CADline
last changed	1999/02/12 15:07

_id	e7b8
authors	Dahl, Veronica
year	1983
title	Logic Programming as a Representation of Knowledge
source	IEEE Computer. IEEE Computer Society, October, 1983. vol. 16: pp. 106-110 : ill. includes bibliography
summary	Logic has traditionally provided a firm conceptual framework for representing knowledge. As it can formally deal with the notion of logical consequence, the introduction of Prolog has made it possible to represent knowledge in terms of logic and also to expect appropriate inferences to be drawn from it automatically. This article illustrates and explores these ideas with respect to two central representational issues: problem solving knowledge and database knowledge. The technical aspects of both subjects have been covered elsewhere (Kowalski, R. Logic for problem solving, North- Holland pub. 1979 ; Dahl, V. on database system development through logic ACM Trans.vol.7/no.3/Mar.1982 pp.102). This explanation uses simple, nontechnical terms
keywords	PROLOG, knowledge, representation, logic, programming, problem solving, database
series	CADline
last changed	1999/02/12 15:08

_id	a747
authors	Eastman, Charles M.
year	1982
title	Recent Developments in Representation in the Science of Design
source	9 p. : ill. Pittsburgh: Design Research Center, CMU, April, 1982. includes bibliography
summary	A recent goal in computer aided design is the representation of a design artifact in a form sufficient to support all analyses and to determine that the design is realizable. In this paper, the implications of the development of computer representations for design specifications are reviewed, some components of a theory of design representations are discussed, and the benefits of such a theory outlined
keywords	CAD, theory, design, representation, architecture, geometric modeling
series	CADline
email
last changed	2003/05/17 10:15

_id	29bb
authors	Fix, George J. and Ernst, Stephan
year	1982
title	Finite Element Methods of the Least Squares Type for Regions with Corners
source	15 p. : ill Pittsburgh: Design Research Center, CMU, April, 1982. includes bibliography.
summary	This paper treats problems with corner singularities. It is shown that if appropriate weights are used in the least squares formulation, then optimal error estimates can be derived in unweighted L2 norms
keywords	computational geometry, finite elements, mathematics
series	CADline
last changed	2003/06/02 13:58

_id	aed6
authors	Hofstadter, Douglas R.
year	1982
title	Metafont, Metamathematics, and Metaphysics
source	23, [38] p. : ill. Bloomington: Computer Science Department, Indiana University, december, 1982. Technical report No. 136. includes bibliography.--- Comments on Donald Knuth's Article 'The Concept of a Meta-Font.' --- See also Donald Knuth's 'The Concept of a Meta-Font,' Visible Language, (Winter 1982), vol. XVI, no. 1, pp. 3-27
summary	It is argued that readers are likely to carry away from Donald Knuth's article 'The Concept of a Meta-Font' a falsely optimistic view of the extent to which the design of typefaces and letterforms can be mechanized through an approach depending on describing letterforms by specifying the settings of a large number of parameters. Through a comparison to mathematical logic, it is argued that no such set of parameters can capture the essence of any semantic category. Some different ways of thinking about the problem of the 'spirit' residing behind any letterform are suggested, connecting to current research issues in the field of artificial intelligence
keywords	languages, AI, parametrization
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	e234
authors	Kalay, Yehuda E. and Harfmann, Anton C.
year	1985
title	An Integrative Approach to Computer-Aided Design Education in Architecture
source	February, 1985. [17] p. : [8] p. of ill
summary	With the advent of CAD, schools of architecture are now obliged to prepare their graduates for using the emerging new design tools and methods in architectural practices of the future. In addition to this educational obligation, schools of architecture (possibly in partnership with practicing firms) are also the most appropriate agents for pursuing research in CAD that will lead to the development of better CAD software for use by the profession as a whole. To meet these two rather different obligations, two kinds of CAD education curricula are required: one which prepares tool- users, and another that prepares tool-builders. The first educates students about the use of CAD tools for the design of buildings, whereas the second educates them about the design of CAD tools themselves. The School of Architecture and Planning in SUNY at Buffalo has recognized these two obligations, and in Fall 1982 began to meet them by planning and implementing an integrated CAD environment. This environment now consists of 3 components: a tool-building sequence of courses, an advanced research program, and a general tool-users architectural curriculum. Students in the tool-building course sequence learn the principles of CAD and may, upon graduation, become researchers and the managers of CAD systems in practicing offices. While in school they form a pool of research assistants who may be employed in the research component of the CAD environment, thereby facilitating the design and development of advanced CAD tools. The research component, through its various projects, develops and provides state of the art tools to be used by practitioners as well as by students in the school, in such courses as architectural studio, environmental controls, performance programming, and basic design courses. Students in these courses who use the tools developed by the research group constitute the tool-users component of the CAD environment. While they are being educated in the methods they will be using throughout their professional careers, they also act as a 'real-world' laboratory for testing the software and thereby provide feedback to the research component. The School of Architecture and Planning in SUNY at Buffalo has been the first school to incorporate such a comprehensive CAD environment in its curriculum, thereby successfully fulfilling its obligation to train students in the innovative methods of design that will be used in architectural practices of the future, and at the same time making a significant contribution to the profession of architecture as a whole. This paper describes the methodology and illustrates the history of the CAD environment's implementation in the School
keywords	CAD, architecture, education
series	CADline
email
last changed	2003/06/02 13:58

_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	5509
authors	Koutamanis, Alexandros
year	1990
title	Development of a computerized handbook of architectural plans
source	Delft University of Technology
summary	The dissertation investigates an approach to the development of visual / spatial computer representations for architectural purposes through the development of the computerized handbook of architectural plans (chap), a knowledge-based computer system capable of recognizing the metric properties of architectural plans. This investigation can be summarized as an introduction of computer vision to the computerization of architectural representations: chap represents an attempt to automate recognition of the most essential among conventional architectural drawings, floor plans. The system accepts as input digitized images of architectural plans and recognizes their spatial primitives (locations) and their spatial articulation on a variety of abstraction levels. The final output of chap is a description of the plan in terms of the grouping formations detected in its spatial articulation. The overall structure of the description is based on an analysis of its conformity to the formal rules of its “stylistic” context (which in the initial version of chap is classical architecture). Chapter 1 suggests that the poor performance of computerized architectural drawing and design systems is among others evidence of the necessity to computerize visual / spatial architectural representations. A recognition system such as chap offers comprehensive means for the investigation of a methodology for the development and use of such representations. Chapter 2 describes a fundamental task of chap: recognition of the position and shape of locations, the atomic parts of the description of an architectural plan in chap. This operation represents the final and most significant part of the first stage in processing an image input in machine environment. Chapter 3 moves to the next significant problem, recognition of the spatial arrangement of locations in an architectural plan, that is, recognition of grouping relationships that determine the subdivision of a plan into parts. In the absence of systematic and exhaustive typologic studies of classical architecture that would allow us to define a repertory of the location group types possible in classical architectural plans, Chapter 3 follows a bottom-up approach based on grouping relationships derived from elementary architectural knowledge and formalized with assistance from Gestalt theory and its antecedents. The grouping process described in Chapter 3 corresponds both in purpose and in structure to the derivation of a description of an image in computer vision [Marr 1982]. Chapter 4 investigates the well-formedness of the description of a classical architectural plan in an analytical manner: each relevant level (or sublevel) of the classical canon according to Tzonis & Lefaivre [1986] is transformed into a single group of criteria of well-formedness which is investigated independently. The hierarchical structure of the classical canon determines the coordination of these criteria into a sequence of cognitive filters which progressively analyses the correspondence of the descriptions derived as in Chapter 3 to the constraints of the canon. The methodology and techniques presented in the dissertation are primarily considered with respect to chap, a specific recognition system. The resulting specification of chap gives a measure of the use of such a system within the context of a computerized collection of architectural precedents and also presents several extensions to other areas of architecture. Although these extensions are not considered as verifiable claims, Chapter 5 describes some of their implications, including on the role of architectural drawing in computerized design systems, on architectural typologies, and on the nature and structure of generative systems in architecture.
series	thesis:PhD
email
last changed	2003/02/12 22:37

_id	79bb
authors	Laing Lamond W. W.
year	1982
title	Computer aided architectural design simulation by computer of the flow of people through a variety of building types
source	University of Strathclyde
series	thesis:PhD
last changed	2003/02/12 22:37

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