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	e1d1
authors	Shafer, Steven A. and Kanade, Takeo
year	1982
title	Using Shadows in Finding Surface Orientations
source	61 p. : ill.` Pittsburgh, PA: Department of Computer Science, CMU, January, 1982. CMU-CS- 82-100
summary	Given a line drawing from an image with shadow regions identified, the shapes of the shadows can be used to generate constraints on the orientations of the surfaces involved. This paper describes the theory which governs those constraints under orthography. A 'Basic Shadow Problem' is first posed, in which there is a single light source, and a single surface casts a shadow on another (background) surface. There are six parameters to determine: the orientation (2 parameters) for each surface, and the direction of the vector (2 parameters) pointing at the light source. If some set of 3 of these are given in advance, the remaining 3 can then be determined geometrically
keywords	The solution method consists of identifying 'illumination surfaces' consisting of illumination vectors, assigning Huffman-Clowes line labels to
series	CADline
last changed	2003/06/02 13:58

_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	48a2
authors	Bergstrom, Axel Lennart
year	1982
title	Computer Graphics in Community Planning
source	June, 1982. 3 p
summary	The digitized map of Sweden uses a technique for graphical presentation in color based on an automatic drawing machine called the 'color ink jet plotter.' A short description of this project is given
keywords	mapping, computer graphics
series	CADline
last changed	1999/02/12 15:07

_id	ad2e
authors	Fix, George J. and Gunzburger, Max D.
year	1982
title	On Numerical Methods for Acoustic Problems
source	14 p. : ill. Pittsburgh: Design Research Center, CMU, April, 1982. include bibliography: p. 12
summary	Finite element methods are introduced for the approximate solution of periodic acoustic problems. A least squares technique is used for those problems which are governed by a first order system of partial differential equations while for second order equations, a Galerkin/multigrid technique is employed. In both cases, the solution process for the algebraic system resulting from discretization is iterative in character
keywords	acoustics, finite elements, mathematics
series	CADline
last changed	2003/06/02 10:24

_id	0dfa
authors	Giuse, Dario
year	1982
title	DP - Command Set
source	24, [22] p. : ill. July, 1982. includes bibliography
summary	This is a short description of the command set of the Drawing Program (DP), a general-purpose graphics editor that runs on a personal computer. This paper contains general notions about the program, the complete description of the commands and a set of advanced techniques for DP users
keywords	software, programming, drafting, systems
series	CADline
last changed	1999/02/12 15:08

_id	c1bf
authors	Gouraud, H.
year	1982
title	Continuous shading of curved surfaces
source	IEEE Transactions on Computers, 20, no. 6, 623-629
summary	A procedure for computing shaded pictures of curved surfaces is presented. The surface is approximated by small polygons in order to solve easily the hidden-parts problem, but the shading of each polygon is computed so that the discontinuities of shade are eliminated across the surface and a smooth appearance is obtained. In order to achieve speed efficiency, the technique developed by Watkins is used which makes possible a hardware implementation of this algorithm.
series	journal paper
last changed	2003/04/23 15:14

_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	2c13
authors	Knuth, Donald E.
year	1982
title	The Concept of a Meta-Font
source	Visible Language. Winter, 1982. vol. XVI: pp. 3-27 : ill. includes bibliography
summary	A single drawing of a single letter reveals only a small part of what was in the designer's mind when that letter was drawn. But when precise instructions are given about how to make such a drawing, the intelligence of that letter can be captured in a way that permits us to obtain an infinite variety of related letters from the same specification. Instead of merely describing a single letter, such instructions explain how that letter would change its shape if other parameters of the design were changed. Thus an entire font of letters and other symbols can be specified so that each character adapts itself to varying conditions in an appropriate way. Initial experiments with a precise language for pen motions suggest strongly that the font designer of the future should not simply design isolated alphabets; the challenge will be to explain exactly how each design should adapt itself gracefully to a wide range of changes in the specification. This paper gives examples of a meta-font and explains the changeable parameters in its design
keywords	programming, computer graphics, parametrization
series	CADline
last changed	2003/06/02 13:58

_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	233c
authors	Udupa, Jayaram K., Srihari, Sargur N. and Herman, Gabor T.
year	1982
title	Boundary Detection in Multidimensions
source	IEEE Transactions on Pattern Analysis and Machine Intelligence. January, 1982. vol. PAM-4: pp. 41-50 : ill. includes bibliography
summary	The development of image processing algorithms for time varying imagery and computerized tomography data calls for generalization of the concepts of adjacency, connectivity, boundary, etc. to three and four dimensional discrete spaces. This paper defines these basic concepts in unified terminology and presents algorithms for a boundary detection task in multidimensional space. The performance of these algorithms is discussed with respect to theoretical maximum complexity, and is illustrated with simulated computerized tomography data
keywords	algorithms, image processing, performance, applications
series	CADline
last changed	2003/06/02 13:58

_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	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	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	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

_id	cf2003_m_040
id	cf2003_m_040
authors	BAY, Joo-Hwa
year	2003
title	Making Rebuttals Available Digitally for Minimising Biases in Mental Judgements
source	Digital Design - Research and Practice [Proceedings of the 10th International Conference on Computer Aided Architectural Design Futures / ISBN 1-4020-1210-1] Tainan (Taiwan) 13–15 October 2003, pp. 147-156
summary	The problem of heuristic biases (illusions) discussed by Tversky and Kahneman (1982) that can lead to errors in judgement by human designers, when they use precedent knowledge presented graphically (Bay 2001). A Cognitive framework of belief, goal, and decision, and a framework of representation of architectural knowledge by Tzonis are used to map out the problem of heuristic biases in the human mind. These are used to discuss what aspects of knowledge can be presented explicitly and digitally to users to make rebuttal more available for human thinking at the cognitive level. The discussion is applicable to both inductive and analytic digital knowledge systems that use precedent knowledge. This discussion is targeted directly at means of addressing bias in the human mind using digital means. The problem of human bias in machine learning and generalisation are discussed in a different paper, and the problems of international or non-intentional machine bias are not part of discussion in this paper.
keywords	analogy, bias, design thinking, environmental design, heuristics
series	CAAD Futures
last changed	2003/11/22 07:26

_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	cc3e
authors	Bloom, Gregory L.
year	1982
title	Solving Architectural and Engineering Problems with CADD: Some Guidelines in Choosing the Right System
source	computer Graphics News. September/October 1982. [3] p
summary	To be useful, a CAD system intended for architectural engineering work must have a number of characteristics in addition to appropriate hardware or software. The article discusses some of these guidelines
keywords	CAD, engineering, architecture, practice
series	CADline
last changed	2003/06/02 13:58

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