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

PDF papers
References

Hits 1 to 20 of 143

Reformat results as: short short into frame detailed detailed into frame

_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	644f
authors	Bijl, Aart
year	1986
title	Designing with Words and Pictures in a Logic Modelling Environment
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 128-145
summary	At EdCAAD we are interested in design as something people do. Designed artefacts, the products of designing, are interesting only in so far as they tell us something about design. An extreme expression of this position is to say that the world of design is the thoughts in the heads of designers, plus the skills of designers in externalizing their thoughts; design artifacts, once perceived and accepted in the worlds of other people, are no longer part of the world of design. We can describe design, briefly, as a process of synthesis. Design has to achieve a fusion between parts to create new parts, so that the products are recognized, as having a right and proper place in the world of people. Parts should be understood as referring to anything - physical objects, abstract ideas, aspirations. These parts occur in some design environment from which parts are extracted, designed upon and results replaced; in the example of buildings, the environment is people and results have to be judged by reference to that environment. It is characteristic of design that both the process and the product are not subject to explicit and complete criteria. This view of design differs sharply from the more orthodox understanding of scientific and technological endeavours which rely predominantly on a process of analysis. In the latter case, the approach is to decompose a problem into parts until individual parts are recognized as being amenable to known operations and results are reassembled into a solution. This process has a peripheral role in design when evaluating selected aspects of tentative design proposals, but the absence of well-defined and widely recognized criteria for design excludes it from the main stream of analytical developments.
series	CAAD Futures
last changed	2003/11/21 15:16

_id	63d0
authors	Carrara, Gianfranco and Novembri, Gabriele
year	1986
title	Constraint-bounded design search
source	Computer-Aided Architectural Design Futures [CAAD Futures Conference Proceedings / ISBN 0-408-05300-3] Delft (The Netherlands), 18-19 September 1985, pp. 146-157
summary	The design process requires continual checking of the consistency of design choices against given sets of goals that have been fulfilled. Such a check is generally performed by comparing abstract representations of design goals with these of the sought real building objects (RBO) resulting from complex intellectual activities closely related to the designer's culture and to the environment in which he operates. In this chapter we define a possible formalization of such representations concerning the goals and the RBO that are usually considered in the architectural design process by our culture in our environment. The representation of design goals is performed by expressing their objective aspects (requirements) and by defining their allowable values (performance specifications). The resulting system of requirements defines the set of allowable solutions and infers an abstract representation of the sought building objects (BO) that consists of the set of characteristics (attributes and relations) which are considered relevant to represent the particular kind of RBO with respect to the consistency check with design goals. The values related to such characteristics define the performances of the RBO while their set establishes its behaviour. Generally speaking, there is no single real object corresponding to an abstract representation but the whole class of the RBO that are equivalent with respect to the values assumed by the considered characteristics. The more we increase the number of these, as well as their specifications, the smaller the class becomes until it coincides with a single real object - given that the assessed specifications be fully consistent. On the other hand, the corresponding representation evolves to the total prefiguration of the RBO. It is not therefore possible to completely define a BO representation in advance since this is inferred by the considered goals and is itself a result of the design process. What can only be established in advance is that any set of characteristics assumed to represent any RBO consists of hierarchic, topological, geometrical and functional relations among the parts of the object at any level of aggregation (from components to space units, to building units, to the whole building) that we define representation structure (RS). Consequently the RS may be thought as the elementary structures that, by superposition and interaction, set up the abstract representation that best fit with design goals.
series	CAAD Futures
last changed	1999/04/03 17:58

_id	avocaad_2001_02
id	avocaad_2001_02
authors	Cheng-Yuan Lin, Yu-Tung Liu
year	2001
title	A digital Procedure of Building Construction: A practical project
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	In earlier times in which computers have not yet been developed well, there has been some researches regarding representation using conventional media (Gombrich, 1960; Arnheim, 1970). For ancient architects, the design process was described abstractly by text (Hewitt, 1985; Cable, 1983); the process evolved from unselfconscious to conscious ways (Alexander, 1964). Till the appearance of 2D drawings, these drawings could only express abstract visual thinking and visually conceptualized vocabulary (Goldschmidt, 1999). Then with the massive use of physical models in the Renaissance, the form and space of architecture was given better precision (Millon, 1994). Researches continued their attempts to identify the nature of different design tools (Eastman and Fereshe, 1994). Simon (1981) figured out that human increasingly relies on other specialists, computational agents, and materials referred to augment their cognitive abilities. This discourse was verified by recent research on conception of design and the expression using digital technologies (McCullough, 1996; Perez-Gomez and Pelletier, 1997). While other design tools did not change as much as representation (Panofsky, 1991; Koch, 1997), the involvement of computers in conventional architecture design arouses a new design thinking of digital architecture (Liu, 1996; Krawczyk, 1997; Murray, 1997; Wertheim, 1999). The notion of the link between ideas and media is emphasized throughout various fields, such as architectural education (Radford, 2000), Internet, and restoration of historical architecture (Potier et al., 2000). Information technology is also an important tool for civil engineering projects (Choi and Ibbs, 1989). Compared with conventional design media, computers avoid some errors in the process (Zaera, 1997). However, most of the application of computers to construction is restricted to simulations in building process (Halpin, 1990). It is worth studying how to employ computer technology meaningfully to bring significant changes to concept stage during the process of building construction (Madazo, 2000; Dave, 2000) and communication (Haymaker, 2000).In architectural design, concept design was achieved through drawings and models (Mitchell, 1997), while the working drawings and even shop drawings were brewed and communicated through drawings only. However, the most effective method of shaping building elements is to build models by computer (Madrazo, 1999). With the trend of 3D visualization (Johnson and Clayton, 1998) and the difference of designing between the physical environment and virtual environment (Maher et al. 2000), we intend to study the possibilities of using digital models, in addition to drawings, as a critical media in the conceptual stage of building construction process in the near future (just as the critical role that physical models played in early design process in the Renaissance). This research is combined with two practical building projects, following the progress of construction by using digital models and animations to simulate the structural layouts of the projects. We also tried to solve the complicated and even conflicting problems in the detail and piping design process through an easily accessible and precise interface. An attempt was made to delineate the hierarchy of the elements in a single structural and constructional system, and the corresponding relations among the systems. Since building construction is often complicated and even conflicting, precision needed to complete the projects can not be based merely on 2D drawings with some imagination. The purpose of this paper is to describe all the related elements according to precision and correctness, to discuss every possibility of different thinking in design of electric-mechanical engineering, to receive feedback from the construction projects in the real world, and to compare the digital models with conventional drawings.Through the application of this research, the subtle relations between the conventional drawings and digital models can be used in the area of building construction. Moreover, a theoretical model and standard process is proposed by using conventional drawings, digital models and physical buildings. By introducing the intervention of digital media in design process of working drawings and shop drawings, there is an opportune chance to use the digital media as a prominent design tool. This study extends the use of digital model and animation from design process to construction process. However, the entire construction process involves various details and exceptions, which are not discussed in this paper. These limitations should be explored in future studies.
series	AVOCAAD
email
last changed	2005/09/09 10:48

_id	23bc
authors	Demko, Stephen, Hodges, Laurie and Naylor, Bruce F.
year	1985
title	Construction of Fractal Objects with Iterated Function Systems
source	SIGGRAPH '85 Conference Proceedings. July, 1985. vol. 19 ; no. 3: pp. 271-278 : ill. col. includes bibliography
summary	In computer graphics, geometric modeling of complex objects is a difficult process. An important class of complex objects arise from natural phenomena: trees, plants, clouds, mountains, etc. Researchers are investigating a variety of techniques for extending modeling capabilities to include these as well as other classes. One mathematical concept that appears to have significant potential for this is fractals. Much interest currently exists in the general scientific community in using fractals as a model of complex natural phenomena. However, only a few methods for generating fractal sets are known. We have been involved in the development of a new approach to computing fractals. Any set of linear maps (affine transformations) and an associated set of probabilities determines an Iterated Function System (IFS). Each IFS has a unique 'attractor' which is typically a fractal set (object). Specification of only a few maps can produce very complicated objects. Design of fractal objects is made relatively simple and intuitive by the discovery of an important mathematical property relating the fractal sets to the IFS. The method also provides the possibility of solving the inverse problem, given the geometry of an object, determine an IFS that will (approximately) generate that geometry. This paper presents the application of the theory of IFS to geometric modeling
keywords	computer graphics, geometric modeling, fractals, visualization
series	CADline
last changed	2003/06/02 13:58

_id	acadia06_068
id	acadia06_068
authors	Elys, John
year	2006
title	Digital Ornament
doi	https://doi.org/10.52842/conf.acadia.2006.068
source	Synthetic Landscapes [Proceedings of the 25th Annual Conference of the Association for Computer-Aided Design in Architecture] pp. 68-78
summary	Gaming software has a history of fostering development of economical and creative methods to deal with hardware limitations. Traditionally the visual representation of gaming software has been a poor offspring of high-end visualization. In a twist of irony, this paper proposes that game production software leads the way into a new era of physical digital ornament. The toolbox of the rendering engine evolved rapidly between 1974-1985 and it is still today, 20 years later the main component of all visualization programs. The development of the bump map is of particular interest; its evolution into a physical displacement map provides untold opportunities of the appropriation of the 2D image to a physical 3D object.To expose the creative potential of the displacement map, a wide scope of existing displacement usage has been identified: Top2maya is a scientific appropriation, Caruso St John Architects an architectural precedent and Tord Boonje’s use of 2D digital pattern provides us with an artistic production precedent. Current gaming technologies give us an indication of how the resolution of displacement is set to enter an unprecedented level of geometric detail. As modernity was inspired by the machine age, we should be led by current technological advancement and appropriate its usage. It is about a move away from the simplification of structure and form to one that deals with the real possibilities of expanding the dialogue of surface topology. Digital Ornament is a kinetic process rather than static, its intentions lie in returning the choice of bespoke materials back to the Architect, Designer and Artist.
series	ACADIA
email
last changed	2022/06/07 07:55

_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	17eb
authors	Lehtonen, H.
year	1985
title	On the principles of visualisation of planning
source	Espoo, Technical Research Centre of Finland, Laboratory of Land Use. Report available from the Laboratory
summary	Contributed by Susan Pietsch (spietsch@arch.adelaide.edu.au)
keywords	3D City Modeling, Development Control, Design Control
series	other
last changed	2001/06/04 20:41

_id	85d0
authors	Peachey, Darwyn R.
year	1985
title	Solid Texturing of Complex Surfaces
source	SIGGRAPH '85 Conference Proceedings. July, 1985. vol. 19 ; no. 3: pp. 279-286 : ill. includes bibliography
summary	Texturing is an effective method of simulating surface detail at relatively low cost. Traditionally, texture functions have been defined on the two-dimensional surface coordinate systems of individual surface patches. This paper introduces the notion of 'solid texturing.' Solid texturing uses texture functions defined throughout a region of three-dimensional space. Many nonhomogeneous materials, including wood and stone, may be more realistically rendered using solid texture functions. In addition, solid texturing can easily be applied to complex surfaces which are difficult to texture using two- dimensional texture functions. The paper gives examples of solid texture functions based on Fourier synthesis, stochastic texture models, projections of two-dimensional textures, and combinations of other solid textures
keywords	shading, texture mapping, solid modeling, objects, computer graphics, rendering, visualization
series	CADline
last changed	2003/06/02 10:24

_id	0ecb
authors	Waerum, Jens and Rüdiger Kristiansen, Bjarne
year	1989
title	CAAD Education at the School of Architecture Copenhagen
doi	https://doi.org/10.52842/conf.ecaade.1989.x.q8k
source	CAAD: Education - Research and Practice [eCAADe Conference Proceedings / ISBN 87-982875-2-4] Aarhus (Denmark) 21-23 September 1989, pp. 4.5.1-4.5.9
summary	The establishment of Datacentret (the Data Centre) in summer 1985 was preceded by 15 years slow- moving, arduous work from the early experiments in what was then the computing laboratory under the supervision of architect Per Jacobi, author of the Danish 3D drawing system MONSTER, until 1984, when a special committee was commissioned to draw up proposals for the introduction of teaching in computing at the Architects School. In spring 1985 the school administrators decided that a central computer workshop should be set up and in cooperation with the school's institutes placed jointly in charge of instructing teachers and students, carrying out research and development within the field of architecture and taking steps to work out a curriculum of supplementary training for practising architects. With the aid of a special grant, 12 PC's were successfully acquired in the 2 years that followed, as well as a screen projector and other peripherals.
series	eCAADe
last changed	2022/06/07 07:50

_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	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	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	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

_id	2928
authors	Barsky, Brian A. and De Rose, Tony D.
year	1985
title	The Beta2-spline : A Special Case of the Beta-spline Curve and Surface Representation
source	IEEE Computer Graphics and Applications September, 1985. vol. 5: pp. 46-58 : ill. includes bibliography.
summary	This article develops a special case of the Beta-spline curve and surface technique called the Beta2-spline. While a general Beta-spline has two parameters (B1 and B2) controlling its shape, the special case presented here has only the single parameter B2. Experience has shown this to be a simple but very useful special case that is computationally more efficient than the general case. Optimized algorithms for the evaluation of the Beta2-spline basis functions and rendering of Beta2-spline curves and surfaces via subdivision are presented. This technique is proving to be quite useful in the modeling of complex shapes. The representation is sufficiently general and flexible so as to be capable of modeling irregular curved-surface objects such as automobile bodies, aircraft fuselages, ship hulls, turbine blades, and bottles
keywords	B-splines, curved surfaces, computational geometry, representation, algorithms, computer graphics, rendering
series	CADline
last changed	2003/06/02 14:41

_id	2d64
authors	Batori, D.S. and Kim, W.
year	1985
title	Modeling Concepts for VLSI CAD Objects
source	ACM Transactions on Database Systems 10 No. 3 - pp. 322-346
summary	VLSI CAD applications deal with design objects that have an interface description and an implementation description. Versions of design objects have a common interface but differ in their implementations. A molecular object is a modeling construct which enables a database entity to be represented by two sets of heterogeneous records, one set describes the object's interface and the other describes its implementation. Thus a reasonable starting point for modeling design objects is to begin with the concept of molecular objects. In this paper, we identify modeling concepts that are fundamental to capturing the semantics of VLSI CAD design objects and versions in terms of molecular objects. A provisional set of user operations on design objects, consistent with these modeling concepts, is also defined. The modeling framework that we present has been found useful for investigating physical storage techniques and change notification problems in version control. REFERENCES
series	journal paper
last changed	2003/11/21 15:16

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

_id	ddss9408
id	ddss9408
authors	Bax, Thijs and Trum, Henk
year	1994
title	A Taxonomy of Architecture: Core of a Theory of Design
source	Second Design and Decision Support Systems in Architecture & Urban Planning (Vaals, the Netherlands), August 15-19, 1994
summary	The authors developed a taxonomy of concepts in architectural design. It was accepted by the Advisory Committee for education in the field of architecture, a committee advising the European Commission and Member States, as a reference for their task to harmonize architectural education in Europe. The taxonomy is based on Domain theory, a theory developed by the authors, based on General Systems Theory and the notion of structure according to French Structuralism, takes a participatory viewpoint for the integration of knowledge and interests by parties in the architectural design process. The paper discusses recent developments of the taxonomy, firstly as a result of a confrontation with similar endeavours to structure the field of architectural design, secondly as a result of applications of education and architectural design practice, and thirdly as a result of theapplication of some views derived from the philosophical work from Charles Benjamin Peirce. Developments concern the structural form of the taxonomy comprising basic concepts and levelbound scale concepts, and the specification of the content of the fields which these concepts represent. The confrontation with similar endeavours concerns mainly the work of an ARCUK workingparty, chaired by Tom Marcus, based on the European Directive from 1985. The application concerns experiences with a taxonomy-based enquiry in order to represent the profile of educational programmes of schools and faculties of architecture in Europe in qualitative and quantitative terms. This enquiry was carried out in order to achieve a basis for comparison and judgement, and a basis for future guidelines including quantitative aspects. Views of Peirce, more specifically his views on triarchy as a way of ordering and structuring processes of thinking,provide keys for a re-definition of concepts as building stones of the taxonomy in terms of the form-function-process-triad, which strengthens the coherence of the taxonomy, allowing for a more regular representation in the form of a hierarchical ordered matrix.
series	DDSS
last changed	2003/08/07 16:36

_id	ddss9409
id	ddss9409
authors	Beekman, Solange and Rikhof, Herman G.A.
year	1994
title	Strategic Urban Planning in the Netherlands
source	Second Design and Decision Support Systems in Architecture & Urban Planning (Vaals, the Netherlands), August 15-19, 1994
summary	Since the mid-1980s, several Dutch towns have initiated many urban planning and design activities for their existing area. This represented a shift in that previous urban planning projects typicallyconcerned expansion in the outskirts of the city, or urban renewal. The complex and expensive renovation of the existing housing stock rarely allowed a deep interest in urban design. Since 1985, attention shifted from the housing stock to the city as a whole. Furthermore, public andprivate actors increasingly become involved in the planning process. It became clear that a more comprehensive plan for the whole existing town or region was needed. Conventional planning instruments were considered ill-suited for this new challenge. The paper discusses promising attempts of various urban planning instruments to get a stronger but also more flexible hold on thetransformation of the urban planning area in the Netherlands. These new planning instruments have three common characteristics: (i) they give special attention to the different levels of urban management needed for different urban areas, (ii) these strategic plans provide an integral view on the urban developments, and (iii) these plans introduce a new strategy to deal with both private initiatives to transform urban sites and monitor wishes, proposals, etc. from inhabitants in the neighbourhoods. A comparative analyses of several cities indicates, however, that, in addition to these common characteristics, major differences between their strategic plans exist depending upon their historic patrimonium, economic status and planning tradition.
series	DDSS
email
last changed	2003/08/07 16:36

_id	c3b1
authors	Berry, R. E. and Meekings, B.A.E.
year	1985
title	A Style Analysis of C Programs
source	communications of the ACM. January, 1985. vol. 29: pp. 80-88
summary	Since programming is considered by many to be learned by experience and example, rather than instruction, the authors analyzed code produced by professional programmers. C programs comprising the UNIX operating system and its utilities were chosen. The authors have arbitrarily selected a large body of professionally produced code and subjected it to 'stylish analysis.' Each program was given a percentage 'score' for style that consists of contributions in varying degrees from various program features like module length, line length, reserved words etc
keywords	languages, C, programming, techniques
series	CADline
last changed	2003/06/02 13:58

For more results click below: