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	4275
authors	Cowan, David
year	1985
title	Artificial Intelligence at Edinburgh University
source	computer Aided Design. November, 1985. vol. 17: pp. 465-468
summary	The development of research into the area of artificial intelligence is described. It was first recognized by Edinburgh University as an independent discipline in 1966 and there is now an Artificial Intelligence Applications Institute. The main areas of artificial intelligence research are summarized. The five projects carried out with Alvey funding are examined in more detail. They cover such topics as natural language and text processing, 3D modelling and expert systems
keywords	AI, expert systems, modeling, natural languages
series	CADline
last changed	1999/02/12 15:07

_id	78ca
authors	Friedland, P. (Ed.)
year	1985
title	Special Section on Architectures for Knowledge-Based Systems
source	CACM (28), 9, September
summary	A fundamental shift in the preferred approach to building applied artificial intelligence (AI) systems has taken place since the late 1960s. Previous work focused on the construction of general-purpose intelligent systems; the emphasis was on powerful inference methods that could function efficiently even when the available domain-specific knowledge was relatively meager. Today the emphasis is on the role of specific and detailed knowledge, rather than on reasoning methods.The first successful application of this method, which goes by the name of knowledge-based or expert-system research, was the DENDRAL program at Stanford, a long-term collaboration between chemists and computer scientists for automating the determination of molecular structure from empirical formulas and mass spectral data. The key idea is that knowledge is power, for experts, be they human or machine, are often those who know more facts and heuristics about a domain than lesser problem solvers. The task of building an expert system, therefore, is predominantly one of teaching" a system enough of these facts and heuristics to enable it to perform competently in a particular problem-solving context. Such a collection of facts and heuristics is commonly called a knowledge base. Knowledge-based systems are still dependent on inference methods that perform reasoning on the knowledge base, but experience has shown that simple inference methods like generate and test, backward-chaining, and forward-chaining are very effective in a wide variety of problem domains when they are coupled with powerful knowledge bases. If this methodology remains preeminent, then the task of constructing knowledge bases becomes the rate-limiting factor in expert-system development. Indeed, a major portion of the applied AI research in the last decade has been directed at developing techniques and tools for knowledge representation. We are now in the third generation of such efforts. The first generation was marked by the development of enhanced AI languages like Interlisp and PROLOG. The second generation saw the development of knowledge representation tools at AI research institutions; Stanford, for instance, produced EMYCIN, The Unit System, and MRS. The third generation is now producing fully supported commercial tools like KEE and S.1. Each generation has seen a substantial decrease in the amount of time needed to build significant expert systems. Ten years ago prototype systems commonly took on the order of two years to show proof of concept; today such systems are routinely built in a few months. Three basic methodologies-frames, rules, and logic-have emerged to support the complex task of storing human knowledge in an expert system. Each of the articles in this Special Section describes and illustrates one of these methodologies. "The Role of Frame-Based Representation in Reasoning," by Richard Fikes and Tom Kehler, describes an object-centered view of knowledge representation, whereby all knowldge is partitioned into discrete structures (frames) having individual properties (slots). Frames can be used to represent broad concepts, classes of objects, or individual instances or components of objects. They are joined together in an inheritance hierarchy that provides for the transmission of common properties among the frames without multiple specification of those properties. The authors use the KEE knowledge representation and manipulation tool to illustrate the characteristics of frame-based representation for a variety of domain examples. They also show how frame-based systems can be used to incorporate a range of inference methods common to both logic and rule-based systems.""Rule-Based Systems," by Frederick Hayes-Roth, chronicles the history and describes the implementation of production rules as a framework for knowledge representation. In essence, production rules use IF conditions THEN conclusions and IF conditions THEN actions structures to construct a knowledge base. The autor catalogs a wide range of applications for which this methodology has proved natural and (at least partially) successful for replicating intelligent behavior. The article also surveys some already-available computational tools for facilitating the construction of rule-based knowledge bases and discusses the inference methods (particularly backward- and forward-chaining) that are provided as part of these tools. The article concludes with a consideration of the future improvement and expansion of such tools.The third article, "Logic Programming, " by Michael Genesereth and Matthew Ginsberg, provides a tutorial introduction to the formal method of programming by description in the predicate calculus. Unlike traditional programming, which emphasizes how computations are to be performed, logic programming focuses on the what of objects and their behavior. The article illustrates the ease with which incremental additions can be made to a logic-oriented knowledge base, as well as the automatic facilities for inference (through theorem proving) and explanation that result from such formal descriptions. A practical example of diagnosis of digital device malfunctions is used to show how significantand complex problems can be represented in the formalism.A note to the reader who may infer that the AI community is being split into competing camps by these three methodologies: Although each provides advantages in certain specific domains (logic where the domain can be readily axiomatized and where complete causal models are available, rules where most of the knowledge can be conveniently expressed as experiential heuristics, and frames where complex structural descriptions are necessary to adequately describe the domain), the current view is one of synthesis rather than exclusivity. Both logic and rule-based systems commonly incorporate frame-like structures to facilitate the representation of large amounts of factual information, and frame-based systems like KEE allow both production rules and predicate calculus statements to be stored within and activated from frames to do inference. The next generation of knowledge representation tools may even help users to select appropriate methodologies for each particular class of knowledge, and then automatically integrate the various methodologies so selected into a consistent framework for knowledge. "
series	journal paper
last changed	2003/04/23 15:14

_id	c898
authors	Gero, John S.
year	1986
title	An Overview of Knowledge Engineering and its Relevance to CAAD
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 107-119
summary	Computer-aided architectural design (CAAD) has come to mean a number of often disparate activities. These can be placed into one of two categories: using the computer as a drafting and, to a lesser extent, modelling system; and using it as a design medium. The distinction between the two categories is often blurred. Using the computer as a drafting and modelling tool relies on computing notions concerned with representing objects and structures numerically and with ideas of computer programs as procedural algorithms. Similar notions underly the use of computers as a design medium. We shall return to these later. Clearly, all computer programs contain knowledge, whether methodological knowledge about processes or knowledge about structural relationships in models or databases. However, this knowledge is so intertwined with the procedural representation within the program that it can no longer be seen or found. Architecture is concerned with much more than numerical descriptions of buildings. It is concerned with concepts, ideas, judgement and experience. All these appear to be outside the realm of traditional computing. Yet architects discoursing use models of buildings largely unrelated to either numerical descriptions or procedural representations. They make use of knowledge - about objects, events and processes - and make nonprocedural (declarative) statements that can only be described symbolically. The limits of traditional computing are the limits of traditional computer-aided design systems, namely, that it is unable directly to represent and manipulate declarative, nonalgorithmic, knowledge or to perform symbolic reasoning. Developments in artificial intelligence have opened up ways of increasing the applicability of computers by acquiring and representing knowledge in computable forms. These approaches supplement rather than supplant existing uses of computers. They begin to allow the explicit representations of human knowledge. The remainder of this chapter provides a brief introduction to this field and describes, through applications, its relevance to computer- aided architectural design.
series	CAAD Futures
email
last changed	2003/05/16 20:58

_id	4f6f
authors	Kalay, Yehuda E.
year	1985
title	Knowledge-Based Computer-Aided Design to Assist Designers of Physical Artifacts
source	1985. [15] p. : ill. includes bibliography
summary	The objectives of this project are to increase the productivity of physical designers, and to improve the quality of designed artifacts and environments. The means for achieving these objectives include the development, implementation and verification of a broad-based methodology to be used for building context-sensitive computer-aided design systems to facilitate the design and fabrication of physical artifacts. Such systems will extend computer aides for design over the earliest phases of the design process and thus facilitate design-capture in addition to the common design-communication utilities they currently provide. They will thus constitute intelligent design assistants that will relieve the designer from the necessity to deal with some design details, as well as the need to explicitly manage the consistency of the design database. The project employs principles developed by Artificial Intelligence methods that are used in non-deterministic problem solving processes that represent data and knowledge in distributed networks. Principles such as object-centered data factorization and message-based change propagation techniques are implemented in an existing architectural computer-aided design system and field-tested in a practicing Architectural/Engineering office
keywords	CAD, knowledge base, design methods, design process, architecture
series	CADline
email
last changed	2003/06/02 13:58

_id	e115
authors	Pipes, Alan (Ed.)
year	1986
title	Computer-Aided Architectural Design Futures [Conference Proceedings]
source	International Conference on Computer-Aided Architectural Design / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, 245 p.
summary	Computer-Aided Architectural Design Futures was conceived late one evening in the bar of the Metropole Hotel in Brighton, UK. Those present - veterans of a hundred and one CAD conferences - were bemoaning the degree to which big business was taking over the conference scene: exhibiting was replacing conferring, selling was replacing thinking, products were replacing ideas. Wouldn't it be nice, we agreed, to get back to an 'academic' conference which would take stock of current developments in CAAD and attempt to anticipate the direction of future developments and their impact on architectural practice, on the building industry and on the quality of the built environment? Four major themes are explored in CAAD Futures: (1) Systematic design; (2) Drawing and visualization; (3) Artificial intelligence and knowledge engineering; (4) Implications for practice. // Stimulus papers on these four themes were circulated prior to the Conference, and the conference papers themselves elaborated the issues raised in the stimulus papers in such a way as to encourage discussion. The resulting book, we believe, will be a major reference text for students, researchers and practitioners.
series	CAAD Futures
last changed	1999/04/03 17:58

_id	a36a
authors	Rasdorf, William J.
year	1985
title	Perspectives on Knowledge in Engineering Design
source	Proceedings of the International Computers in Engineering Conference. Boston, MA: American Society of Mechanical Engineers, August, 1985. Vol. 2: pp. 249-253. CADLINE has abstract only
summary	Of all the contributions of artificial intelligence (AI), expert systems show some of the most significant promise for engineering applications. Expert systems provide a framework for acquiring, representing, and using knowledge about a particular application's domain. The role of knowledge in engineering design merits closer attention so that AI- oriented computer-aided engineering (CAE) systems can be developed and maintained systematically. Because 'knowledge' in engineering applications is loosely defined, it is necessary to identify knowledge types and the correlations between them before widespread engineering design applications can be achieved. The types of domain knowledge; facts, procedures, judgments, and control; differ from the classes of that knowledge; creative, innovative, and routine. Feasible tasks for expert systems can be determined based on these types and classes of knowledge. Interpretive tasks require reasoning about a task in light of the knowledge available, while generative tasks create potential solutions to be tested against constraints. Only after classifying the domain by type and level can the engineer select an appropriate knowledge-engineering tool for the domain being considered. The critical features to be weighed after problem classification are knowledge representation techniques, control strategies, interface requirements, compatibility with traditional systems, and economic considerations. After considering all of these factors in the selection of the expert system tool, the engineer can then proceed with the acquisition of knowledge and the construction and the use of the expert system
keywords	knowledge, AI, civil engineering, expert systems, CAE, representation
series	CADline
last changed	2003/06/02 13:58

_id	e16a
authors	Schmitt, Gerhard N.
year	1985
title	Architectural Tool Building: Introduction to Pascal for Architects and Designers Using Graphics on the IBM PC and Macintosh
source	ACADIA Workshop ‘85 [ACADIA Conference Proceedings] Tempe (Arizona / USA) 2-3 November 1985, pp. 119-128
doi	https://doi.org/10.52842/conf.acadia.1985.119
summary	The growing number of architecture and design students that take introductory computing courses justify the development of courses that are tuned to the specific needs of these disciplines. The importance of graphics has to be reflected in these courses and relationships that exist between structured programming and deterministic design problems must be demonstrated. This paper describes such a course - the software and the tutorial developed for it. It is both the introduction for architecture and design students to become competent program users and the foundation and prerequisite for more advanced courses in data structures and Artificial Intelligence for architectural tool building.
series	ACADIA
email
last changed	2022/06/07 07:57

_id	6916
authors	Gasparski, W.
year	1986
title	Design Methodology: How I Understand and Develop it
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 16-27
summary	The term 'methodology' is sometimes given two diametrically opposed meanings, well characterized by Mark Blaug in the preface of a very informative book devoted to the methodology of economics. This is also the case with the methodology of design. One can find studies in which 'the methodology of design' is simply a method or methods of design, given a fancy name to make it or them appear more scientific. Authors of such studies should not confuse their readers by taking methodological studies to mean technicalities of design or demanding that their interpretation and assessment of so-called 'practical applicability' should follow this criterion. The methodology of design - as we understand it has parallels in the methodology of Blaug's economics, the philosophy of practical science, the applied sciences or the sciences of artificial objects or artefacts. Understood this way, the methodology of design is neither the method of practising design nor an instruction for its use but a theoretical reflection - in the meaning given to methodology by the philosophy of science - of design. In this connection a study of the methodology of design should be provided with the subtitle, 'How researchers of practical sciences and designers understand the concept of changes'.
series	CAAD Futures
last changed	1999/04/03 17:58

_id	sigradi2007_af13
id	sigradi2007_af13
authors	Granero, Adriana Edith; Alicia Barrón; María Teresa Urruti
year	2007
title	Transformations in the educational system, Influence of the Digital Graph [Transformaciones en el sistema educacional, influencia de la Gráfica Digital]
source	SIGraDi 2007 - [Proceedings of the 11th Iberoamerican Congress of Digital Graphics] México D.F. - México 23-25 October 2007, pp. 182-186
summary	The educative proposal was based on the summary attained through experiences piled up during the 2 last semester courses, 2/2006-1/2007. This proposal corresponds to a mix of methodology (by personal attendance / by internet). Founding on the Theory of the Game (Eric Berne 1960) and on different theories such as: Multiple intelligences (Haward Gardner 1983), Emotional Intelligence (Peter Salowey and John Mayer 1990, Goleman 1998), Social Intelligence (Goleman 2006), the Triarchy of Intelligence (Stemberg, R.J. 1985, 1997), “the hand of the human power”, it´s established that the power of the voice, that of the imagination, the reward, the commitment and association produce a significant increase of the productivity (Rosabeth Moss Kanter 2000), aside from the constructive processes of the knowledge (new pedagogical concepts constructivista of Ormrod J.E. 2003 and Tim O´Reilly 2004).
series	SIGRADI
email
last changed	2016/03/10 09:52

_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	8e75
authors	Kalay, Yehuda E.
year	1985
title	Redefining the Role of Computers in Architecture : From Drafting/Modeling Tools to Knowledge- Based Design Assistants
source	Computer Aided Design September, 1985. vol. 17: pp. 319-328 : ill. includes bibliography.
summary	This paper argues that the modeling/drafting role computers have been assigned in architectural design should be changed, so that computers will become intelligent assistants to designers, relieving them from the need to perform the more trivial design tasks and augmenting their decision making capabilities. A conceptual framework of a knowledge-based computer-aided design system is presented, and its potential for increasing the utility of computers in the design buildings is discussed
keywords	AI, architecture, design, knowledge base, intelligence, building, CAD
series	CADline
email
last changed	2003/06/02 13:58

_id	a0d4
id	a0d4
authors	Rosa Enrich, Andrea Carnicero, Gustavo Fornari & Pedro Orazzi
year	2004
title	ANALYSIS AND EVALUATION OF MATHEMATICAL LEARNING STRUCTURES
source	Proceedings of the Fourth International Conference of Mathematics & Design, Spetial Edition of the Journal of Mathematics & Design, Volume 4, No.1, pp. 13-21.
summary	Abstract: A series of practical tasks have been done under the general name of “Surfaces in invisible cities”. Each task was based on a story taken from the book The Invisible Cities by Italo Calvino. The research carried out allows to design a pedagogical project which makes evident , generates and connects several intentions, motivations and learning structures. It proposes the use of multi- level languages and readings. Therefore, each task takes more time than that of the proposed mathematical class. Its implementation generates a broader view than that seen at the time of design. From the detailed analysis of the results obtained, the following diverse pedagogical aspects of this work project arise: a. The use of several multiple intelligence: Howard Gardner (1985) found that a man has several distinct intelligence types among which Logical-Mathematical; Spatial; Linguistic -oriented; Musical; Intra-personal; Kinesthetic-Corporal; Interpersonal stand out. Only those types used in the task will be analyzed, making a brief description of each type. b. The architectonic-city planning aspects: architectonic-city planning interpretation of the space imagined after reading the text, with the purpose of identifying figures, shapes, volumes and colors which are expressed via an analogous space. They consist of visual, architectonic and territorial speculations without a rigorous spatial theory and it is pretended that they possess a technical precision at mathematical concept level. c. The mathematical contents: a study of the conical and square shapes present in the designs done and used in a creative manner in students’ compositions following the reading of the story chosen is carried out. An analysis of shapes is performed and mathematical problems are posed within the design context. Traditional sketching methods have been used in task solving and the possibilities offered by the virtual tools are analyzed. Emphasis has been put on the vertical and horizontal interchanges in the Chair, generating changes in knowledge transmission perspectives, thus allowing the sharing of contents, abilities and resources. The architectonic work imagined and created by the students will focus on these different working lines creating a harmonious and significant whole. The work is the result of multiple connections and creative proposals.
keywords	city, geometry, multiple intelligence
series	other
type	normal paper
email
last changed	2005/04/07 12:46

_id	8f9d
authors	Wolchko, Matthew J.
year	1985
title	Strategies Toward Architectural Knowledge Engineering
source	ACADIA Workshop ‘85 [ACADIA Conference Proceedings] Tempe (Arizona / USA) 2-3 November 1985, pp. 69-82
doi	https://doi.org/10.52842/conf.acadia.1985.069
summary	Conventional CAD-drafting systems become more powerful modeling tools with the addition of a linked attribute spreadsheet module. This affords the designer the ability to make design decisions not only in the graphic environment, but also as a consequence of quantitative design constraints made apparent in the spreadsheet. While the spreadsheet interface is easily understood by the user, it suffers from two limitations: it lacks a variety of functional capabilities that would enable it to solve more complex design tasks; also, it can only report on existing conditions in the graphic environment. A proposal is made for the enhancement of the spreadsheet's programming power, creating an interface for the selection of program modules that can solve various architectural design tasks. Due to the complexity and graphic nature of architectural design, it is suggested that both procedural and propositional programming methods be used in concert within such a system. In the following, a suitable design task (artificial illumination-reflected ceiling layout) is selected, and then decomposed into two parts: the quantitative analysis (via the application of a procedural programming algorithm), and a logical model generation using shape grammar rules in a propositional framework.
series	ACADIA
last changed	2022/06/07 07:57

_id	ce52
authors	Abram, Greg, Weslover, Lee and Whitted, Turner
year	1985
title	Efficient Alias-Free Rendering using Bit-masks and Look-up Tables
source	SIGGRAPH '85 Conference Proceedings. July, 1985. vol. 19 ; no. 3: pp. 53-59 : ill. (some col.). includes bibliography
summary	The authors demonstrate methods of rendering alias-free synthetic images using a precomputed convolution integral. The method is based on the observation that a visible polygon fragment's contribution to an image is solely a function of its position and shape, and that within a reasonable level of accuracy, a limited number of shapes represent the majority of cases encountered in images commonly rendered. The basic technique has been applied to several different rendering algorithms. A version of the newly non-uniform sampling technique implemented in the same program but with different tables values was introduced
keywords	algorithms, computer graphics, anti-aliasing
series	CADline
last changed	2003/06/02 13:58

_id	678e
authors	Aish, Robert
year	1986
title	Three-dimensional Input and Visualization
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 68-84
summary	The aim of this chapter is to investigate techniques by which man-computer interaction could be improved, specifically in the context of architectural applications of CAD. In this application the object being designed is often an assembly of defined components. Even if the building is not actually fabricated from such components, it is usually conceptualized in these terms. In a conventional graphics- based CAD system these components are usually represented by graphical icons which are displayed on the graphics screen and arranged by the user. The system described here consists of three- dimensional modelling elements which the user physically assembles to form his design. Unlike conventional architectural models which are static (i.e. cannot be changed by the users) and passive (i.e. cannot be read by a CAD system), this model is both 'user generated' and 'machine readable'. The user can create, edit and view the model by simple, natural modelling activities and without the need to learn complex operating commands often associated with CAD systems. In particular, the user can view the model, altering his viewpoint and focus of attention in a completely natural way. Conventional computer graphics within an associated CAD system are used to represent the detailed geometry which the different three-dimensional icons may represent. In addition, computer graphics are also used to present the output of the performance attributes of the objects being modelled. In the architectural application described in this chapter an energy- balance evaluation is displayed for a building designed using the modelling device. While this system is not intended to offer a completely free-form input facility it can be considered to be a specialist man-machine interface of particular relevance to architects or engineers.
series	CAAD Futures
email
last changed	2003/11/21 15:15

_id	cc15
authors	Ansaldi, Silvia, De Floriani, Leila and Falcidieno, Bianca
year	1985
title	Geometric Modeling of Solid Objects by Using a Face Adjacency Graph Representation
source	SIGGRAPH '85 Conference Proceedings. July, 1985. vol. 19 ; no. 3: pp. 131-139 : ill. includes bibliography
summary	A relational graph structure based on a boundary representation of solid objects is described. In this structure, called Face Adjacency Graph, nodes represent object faces, whereas edges and vertices are encoded into arcs and hyperarcs. Based on the face adjacency graph, the authors define a set of primitive face-oriented Euler operators, and a set of macro operators for face manipulation, which allow a compact definition and an efficient updating of solid objects. The authors briefly describe a hierarchical graph structure based on the face adjacency graph, which provides a representation of an object at different levels of detail. Thus it is consistent with the stepwise refinement process through which the object description is produced
keywords	geometric modeling, graphs, objects, representation, data structures,B-rep, solid modeling, Euler operators
series	CADline
last changed	2003/06/02 10:24

_id	acfe
authors	Archea, John
year	1985
title	Architecture's Unique Position Among the Disciplines : Puzzle-Making vs. Problem Solving
source	CRIT XV, The Architectural Student Journal. Summer, 1985. pp. 20-22
summary	Most disciplines involved in the building process, i.e., programmers, space planners, and engineers work in what may be described as a problem solving mode. They state desired effects as explicit performance criteria before they initiate a decision process and test alternative solutions against those criteria until a fit is attained which falls within known probabilities of success. Architects, however are not problem solvers and they are not seeking explicit information when they design how buildings work. Architects are puzzle- makers, They are primarily concerned with unique design concepts. It is through the act of designing, or puzzle- making, that the architect learn what they want to accomplish and how. With regard to the making of buildings, places or experiences, the architect is a puzzle-maker surrounded by a group of problem solvers who address separate pieces of the puzzle
keywords	puzzle making, design process, problem solving, architecture
series	CADline
last changed	1999/02/12 15:07

_id	8ae8
authors	Ayala, D., P. Brunet and Juan (et al)
year	1985
title	Object Representation by Means of Nominimal Division Quadtrees and Octrees
source	ACM Transactions on Graphics. January, 1985. vol. 4: pp. 41-59 : ill. includes bibliography
summary	Quadtree representation of two-dimensional objects is performed with a tree that describes the recursive subdivision of the more complex parts of a picture until the desired resolution is reached. At the end, all the leaves of the tree are square cells that lie completely inside or outside the object. There are two great disadvantages in the use of quadtrees as a representation scheme for objects in geometric modeling system: The amount of memory required for polygonal objects is too great, and it is difficult to recompute the boundary representation of the object after some Boolean operations have been performed. In the present paper a new class of quadtrees, in which nodes may contain zero or one edge, is introduced. By using these quadtrees, storage requirements are reduced and it is possible to obtain the exact backward conversion to boundary representation. Algorithms for the generation of the quadtree, boolean operation, and recomputation of the boundary representation are presented, and their complexities in time and space are discussed. Three- dimensional algorithms working on octrees are also presented. Their use in the geometric modeling of three-dimensional polyhedral objects is discussed
keywords	geometric modeling, algorithms, octree, quadtree, curves, curved surfaces, boolean operations
series	CADline
last changed	2003/06/02 13:58

_id	2ae0
authors	Bairstow, Jeffrey N.
year	1985
title	Chip Design Made Easy
source	high Technology. June, 1985. pp. 18-25 : ill. includes bibliography: p. 74
summary	The combination of powerful engineering workstations and novel software tools is making custom chip design economical even for engineers without the specific training. The availability of new automated design technology is promoted by the changing market dynamics. The design of an integrated circuit, with hardware choices, is described
keywords	business, AI, electrical engineering, hardware
series	CADline
last changed	2003/06/02 13:58

_id	2730
authors	Balkovich, Edward, Lerman, Steven and Parmelee, Richard P.
year	1985
title	Computing in Higher Education : The ATHENA Experience
source	communications of the ACM. November, 1985. vol. 28: pp. 1214- 1224
summary	In this article the use of computation in higher education is approached from the broad sense of its actual use in the curriculum. The authors try to identify areas where current educational methods have observable deficiencies that might be alleviated by the use of appropriate software/hardware combinations. Project ATHENA at MIT is the example the article is based on
keywords	networks, software, hardware, UNIX, education
series	CADline
last changed	2003/06/02 13:58

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