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	1083
authors	Wu, Rui
year	2002
title	Computer Aided Dimensional Control in Building Construction
source	Eindhoven University of Technology
summary	Dimensional control in the building industry can be defined as the operational techniques and activities that are necessary, during the construction process of a building, for the assurance of the defined dimension quality of a building (Hoof, 1986). Efficient and precise dimensional control of buildings under construction is becoming ever more important because of changes in the construction industry. More prefabricated components are used; more regulations appear; newly designed buildings have more complex shapes, and building construction is speeding up. To ensure the predefined dimensional quality, a plan of dimensional control must be designed, on the basis of building drawings and specifications delivered by architects, before the building is constructed. The dimensional control plan must provide site personnel with adequate information on, among others, setting out and assembling building components, which can often be done by means of Total Stations. The essence of designing a dimensional control plan is to find out which points should be used as positioning points, which points should be set out in advance or controlled afterwards, and not to forget why. In an effort to contribute to the improvement of the dimensional control of on-site construction projects, this research tries to capture the knowledge required to design an adequate dimensional control plan and make that knowledge more generally available, and build a digital connection between CAD systems and Total Stations, focusing on prefabricated concrete building structural elements. The instrument developed in this research for capturing of essential dimensional control information and knowledge makes use of Product Data Technology (PDT) and Knowledge Technology (KT). The chosen solution supports the stochastic analysis of optimal positioning points taking account of various sorts of deviations and their mutual relationships. The resulting information model has been written in a standardized information modelling language called UML (Unified Modelling Language). The model has been implemented in a Dimensional Control System (DCS) and applied in the “La Tour” construction project in Apeldoorn, the Netherlands. The DCS provides a digital way to bridge the floor plan design with dimensional control, predict dimensional deviation limits and output the data needed for a Total Station. The case study of “La Tour” tests the UML model and prototype of the DCS. The results prove that direct positioning of objects (by putting reflectors on the objects and using a Total Station and by inputting coordinates extracted and calculated from the AutoCAD drawings) provides higher speed, accuracy and reliability. It also shows a way to (pre)position free form objects in 3D where traditional methods cannot. In conclusion: (1) it seems to be justified to expect that the application of the DCS will contribute to increased confidence in dimensional control and the reduction of costs of failure, which potentially could support the increased use of cheaper construction methods, and will also contribute to the improvement of building design and construction process. (2) the scientific contribution of this research is a first step towards providing dimensional quality in a construction process covered by stochastic dimensional uncertainty, even for positioning of free form objects.
keywords	Construction Management; Constructional Engineering; Computer Applications
series	thesis:PhD
last changed	2003/02/12 22:37

_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	4ed0
authors	Bartels, R.H., Beatty, J.C. and Barsky, B.A.
year	1986
title	An Introduction to Splines for Use in Computer Graphics and Geometric Modeling
source	xiv, 476 p. : ill. (some col.) Los Altos, California: Morgan Kaufmann Pub. Inc., 1986. Forewords by Pierre Bezier and Robin A. Forrest. Includes bibliography: p. 455-465 and index
summary	Discusses the use of splines from the point of view of the computer scientist concentrating on parametric spline curves and parametric,tensor-product spline surfaces
keywords	splines, theory, computer graphics, computational geometry
series	CADline
last changed	2003/06/02 14:42

_id	aec8
authors	Bellinghall, Leigh
year	1986
title	The MicroCad Explosion : An Eye to Applications Clarifies Choices
source	computer Graphics World March, 1986. vol. 9: pp. 23-28 : col. ill.
summary	Two strong trends affirm increasing market interest in micro systems. While early programs were developed for personal computers, turnkey system houses are now stretching heavy-duty mini and mainframe-hosted programs down to micros. This article gives a selective survey of popular micro-CAD software, looks at packages in both development areas
keywords	drafting, systems, CAD, software, applications
series	CADline
last changed	1999/02/12 15:07

_id	ed51
authors	Bergeron, Philippe
year	1986
title	A General Version of Crow's Shadow Volumes
source	IEEE Computer Graphics and Applications September, 1986. vol. 6: pp. 17-28 : col. ill. includes bibliography.
summary	In 1977 Frank Crow introduced a new class of algorithms for the generation of shadows. His technique, based on the concept of shadow volumes, assumes a polygonal database and a constrained environment. For example, polyhedrons must be closed, and polygons must be planar. This article presents a new version of Crow's algorithm, developed at the Universite de Montreal, which attempts a less constrained environment. The method has allowed the handling of both open and closed models and nonplanar polygons with the viewpoint anywhere, including any shadow volume. It does not, however, sacrifice the essential features of Crow's original version: penetration between polygons is allowed, and any number of light sources can be defined anywhere in 3D space, including the view volume and any shadow volume. The method has been used successfully in the film Tony de Peltrie and is easily incorporated into an existing scan-line, hidden-surface algorithm
keywords	algorithms, shadowing, polygons, computer graphics
series	CADline
last changed	1999/02/12 15:07

_id	6733
authors	Bettels, Juergen and Myers, David R.
year	1986
title	The PIONS Graphics System
source	IEEE Computer Graphics and Applications. July, 1986. vol. 6: pp. 30-38 : col. ill. includes a short bibliography
summary	During 1979, CERN began to evaluate how interactive computer graphics displays could aid the analysis of high-energy physics experiments at the new Super Proton Synchrotron collider. This work led to PIONS, a 3D graphics system, which features the ability to store and view hierarchical graphics structures in a directed-acyclic-graph database. It is possible to change the attributes of these structures by making selections on nongraphical information also stored in the database. PIONS is implemented as an object-oriented message-passing system based on SmallTalk design principles. It supports multiple viewing transformations, logical input devices, and 2D and 3D primitives. The design allows full use to be made of display hardware that provides dynamic 3D picture transformation
keywords	visualization, computer graphics, database, systems, modeling
series	CADline
last changed	2003/06/02 13:58

_id	09b3
authors	Bier, Eric A. and Sloan, Kenneth R. Jr.
year	1986
title	Two-Part Texture Mappings
source	IEEE Computer Graphics and Applications September, 1986. pp. 40-53 : col. ill. includes bibliography.
summary	Most published techniques for mapping two-dimensional texture patterns onto three-dimensional curved surfaces assume that either the texture pattern has been predistorted to compensate for the distortion of the mapping or the curved surfaces are represented parametrically. The authors address the problem of mapping undistorted planar textures onto arbitrarily represented surfaces. Their mapping technique is done in two parts. First the texture pattern is embedded in 3- space on an intermediate surface. Then the pattern is projected onto the target surface in a way that depends only on the geometry of the target object (not on its parametrization). Both steps have relatively low distortion, so the original texture need not be predistorted. The authors also discuss interactive techniques that make two-part mapping practical
keywords	texture mapping, curved surfaces, computer graphics, rendering
series	CADline
last changed	2003/06/02 10:24

_id	4361
authors	Bishop, G. and Weimer, D.M.
year	1986
title	Fast Phong Shading
source	Computer Graphics (20) 4 pp. 103-106
summary	Computer image generation systems often represent curved surfaces as a mesh of polygons that are shaded to restore a smooth appearance. Phong shading is a well known algorithm for producing a realistic shading but it has not been used by real-time systems because of the 3 additions, 1 division and 1 square root required per pixel for its evaluation. We describe a new formulation for Phong shading that reduces the amount of computation per pixel to only 2 additions for simple Lambertian reflection and 5 additions and 1 memory reference for Phong's complete reflection model. We also show how to extend our method to compute the specular component with the eye at a finite distance from the scene rather than at infinity as is usually assumed. The method can be implemented in hardware for real-time applications or in software to speed image generation for almost any system.
series	journal paper
last changed	2003/11/21 15:16

_id	f5db
authors	Brooks, F.P.
year	1986
title	Walkthrough - A Dynamic Graphics System for Simulating Virtual Buildings
source	Proceedings 1986 Workshop on Interactive 3D Graphics. ACM: 9-22
summary	As part of our graphics research into virtual worlds, we are building a tool for an architect and his client to use for rapid prototyping of buildings by visually "walking through" them in order to refine specifications. Our first prototype simulated the new UNC Computer Science building with some 8000 polygons. BSP-tree software on the Adage Ikonas gave a colored, shaded perspective view every 3-5 seconds while the user moved a cursor in real-time over floorplans shown on the Vector-General 3300. The current (third) version uses Pixel-Planes to generate 9 updates/second, view images shown 4' x 6' by projector. Active short- and long-term research questions include speed-up, stereo, a 6-DoF interface with eye-level defaults, and an interactive model-building, model-changing system.
series	other
last changed	2003/11/21 15:16

_id	a661
authors	Cajati, Claudio and Calandro, Lucia
year	1986
title	Architectural analysis of buildings in order to choice new functional destinations: an application of computer graphics for Faculty of Architecture's students
source	Teaching and Research Experience with CAAD [4th eCAADe Conference Proceedings] Rome (Italy) 11-13 September 1986, pp. 17-19
doi	https://doi.org/10.52842/conf.ecaade.1986.017
summary	The research tries to give a little but meaningful answer to the specific context of the Faculty of Architecture of Naples. Such a context presents a delay of teachers and researchers, in their teaching and researching activity, in beginning the CAAD way. Often the delay is due to a wrong attitude: a too high or too low expectation towards the use of the computer. In such a situation, the chief target of the research is the student of architecture. It is possible and useful to address a clear message, by a simple educational material, just to the student of architecture; not necessarily by producing a software or modifying some existing one, but also applying a given available software to an important architectural question.
series	eCAADe
email
last changed	2022/06/07 07:54

_id	a9b1
authors	Cohen, M.F., Greenberg, D.P. and Immel, D.S. (et al)
year	1986
title	An Efficient Radiosity Approach for Realistic Image Synthesis
source	IEEE Computer Graphics and Applications March, 1986. vol. 6: pp. 26-35 : col. ill. includes bibliography.
summary	The radiosity method models the interaction of light between diffusely reflecting surfaces and accurately predicts the global illumination effects. Procedures are now available to simulate complex environments including occluded and textured surfaces. For accurate rendering, the environment must be discretized into a fine mesh, particularly in areas of high intensity gradients. The interdependence between surfaces implies solution techniques which are computationally intractable. This article describes new procedures to predict the global illumination function without excessive computational expense. Statistics indicate the enormous potential of this approach for realistic image synthesis, particularly for dynamic images of static environments
keywords	computer graphics, radiosity, rendering, algorithms
series	CADline
last changed	2003/06/02 14:42

_id	079f
authors	Dickson, Gary W., DeSanctis, Gerardine and McBride, D. J.
year	1986
title	Understanding the Effectiveness of Computer Graphics for Decision Support : A Cumulative Experimental Approach
source	Communications of the ACM. January, 1986. vol. 29: pp. 40-47. includes bibliography
summary	A total of 840 junior and senior-level undergraduate business students participated in three experiments that compared computer-generated graphical forms of data presentation to traditional tabular reports. The first experiment compared tables and bar charts for their effects on readability, interpretation accuracy, and decision making. No differences in interpretation accuracy or decision quality were observed for the two groups, although tabular reports were rated as 'easier to read and understand' than graphical reports. The second experiment compared line plots to tables for their effects on interpretation accuracy and decision quality. Subjects with graphical reports outperformed those with tables. There were no meaningful differences in interpretation accuracy across treatment groups. The third experiment compared graphical and tabular reports for their ability to convey a 'message' to the reader. Only in situations in which a vast amount of information was presented and relatively simple impressions were to be made, did subjects given graphs outperform those using tables. This program of cumulative experiments indicates that generalized claims of superiority of graphic presentation are unsupported, at least for decision-related activities. In fact, the experiments suggest that the effectiveness of the data display format is largely a function of the characteristics of the task at hand, and that impressions gleaned from 'one shot' studies of the effectiveness of the use of graphs may be nothing more than situationally dependent artifacts
keywords	business, computer graphics, presentation, decision making, visualization
series	CADline
last changed	2003/06/02 13:58

_id	4418
authors	Franklin, Randolph, Wu, Peter, Y. F. and Samaddar, Sumitro (et al)
year	1986
title	Prolog and Geometry Projects
source	IEEE Computer Graphics and Applications. November, 1986. vol. 6: pp. 46-55 : ill. includes bibliography
summary	Prolog is a useful tool for geometry and graphics implementations because its primitives, such as unification, match the requirements of many geometric algorithms. During the last two years, programs have been implemented to solve several problems in Prolog, including a subset of the Graphical Kernel System, convex-hull calculation, planar graph traversal, recognition of groupings of objects, Boolean combinations of polygons using multiple precision rational numbers, and cartographic map overlay. Certain paradigms or standard forms of geometric programming in Prolog are becoming evident. They include applying a function to every element of a set, executing a procedure so long as a certain geometric pattern exists, and using unification to propagate a transitive function. This article describes the experiences, including paradigms of programming that seem useful, and finally lists those considered as the advantages and disadvantages of Prolog
keywords	geometric modeling, computer graphics, PROLOG, programming
series	CADline
last changed	2003/06/02 13:58

_id	a241
authors	Freund, Dwight D.
year	1986
title	A Note : An Interactive Procedure for Constructing Line and Circle Tangencies
source	IEEE Computer Graphics and Applications. April, 1986. vol. 6: pp. 59-63 : ill. includes bibliography
summary	This note describes a procedure that enables a designer or draftsperson with limited mathematical training to discover interactively the construction of a wide variety of tangency and intersection problems. Requiring very little code to implement, it supplements the standard tangency constructions available on commercial turnkey computer-aided-design systems with a flexibility unavailable even through the inclusion of the numerous special-purpose algorithms available in the literature
keywords	drawings, circles, computational geometry, user interface
series	CADline
last changed	2003/06/02 10:24

_id	40fe
authors	Gero, John S., Oxman, Rivka E. and Manago, C.
year	1986
title	Graphics and Expert Systems
source	AUSGRAPH '86 Australian Conference on Computer Graphics (4th : 1986 : Sydney). pp. 25-29 : ill. includes bibliography
summary	Expert systems are a novel software technology which aim to model the behavior and knowledge of human experts. This paper presents two modes of interaction between graphics and expert systems in the domain of computer-aided design. The first concerns the interaction between an expert system and commercial CAD systems. The second demonstrates how expert systems can control design oriented graphical representations. Examples from both modes are presented from systems developed at Sydney University
keywords	computer graphics, expert systems, CAD, architecture
series	CADline
email
last changed	2003/06/02 10:24

_id	a6a9
authors	Goebel, Martin and Kroemker, Detlef
year	1986
title	A Multi-Microprocessor GKS Workstation
source	IEEE Computer Graphics and Applications July, 1986. vol. 6: pp. 54-60 : ill. includes bibliography.
summary	Implementers of graphical application systems hesitate to interface their applications to the GKS standard not only because GKS functionality seems to be less sufficient for a particular application but also because the use of GKS -- as it is offered in portable software implementations -- usually means a loss of system performance. This article describes an installation of GKS on a multi-microprocessor that is based on functional distribution principles as well as on the object-oriented distribution of a graphics system. The main concepts and advantages of a GKS workstation using more than one processing unit with at least one output pipeline are described. The flexibility of this approach opens a perspective view to a GKS workstation that is configurable to application requirements
keywords	standards, GKS, graphs, systems, hardware
series	CADline
last changed	2003/06/02 10:24

_id	0354
authors	Goodman, Gary and Reddy, Raj D.
year	1978
title	Alternative Control Structures for Speech Understanding Systems
source	1978 ? [13] p. : ill. includes bibliography Control structures are an essential part of any speech recognition system. They are the devices by which passive knowledge about the task and language is transformed into active and effective processes. In the chapter, three areas of control structures are defined and discussed: knowledge source interaction, knowledge source activation, and knowledge source focusing. Discussion relates the concepts presented to systems developed during the five-year ARPA speech understanding project. speech recognition / systems / control / structures / AI. 64. Goodman, Tim and Keith Unsworth. 'Manipulating Shape and Producing Geometric Continuity in B-spline Curves.' IEEE Computer Graphics and Applications. February, 1986. vol. 6: pp. 50-56 : ill. includes bibliography.
summary	This article examines some of the desirable features of B- splines that make them particularly suitable for computer- aided design. First, a theoretical analysis is presented regarding the effects upon the shape of a design curve when the bias and tension parameters are allowed to vary in certain ways. Second, the concept of geometric continuity is discussed, and conditions are derived upon the control vertices to ensure that the design curve has second-order geometric continuity. Illustrations of B-spline curves are presented to support the theoretical conclusions
keywords	computational geometry, B-splines, curves, CAD
series	CADline
last changed	2003/06/02 13:58

_id	68aa
authors	Greenberg, Donald P.
year	1986
title	Computer Graphics 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. 63-67
summary	The field of computer graphics has made enormous progress during the past decade. It is rapidly approaching the time when we will be able to create images of such realism that it will be possible to 'walk through' nonexistent spaces and to evaluate their aesthetic quality based on the simulations. In this chapter we wish to document the historical development of computer graphics image creation and describe some techniques which are currently being developed. We will try to explain some pilot projects that we are just beginning to undertake at the Program of Computer Graphics and the Center for Theory and Simulation in Science and Engineering at Cornell University.
series	CAAD Futures
last changed	1999/04/03 17:58

_id	e65f
authors	Haines, Eric A. and Greenberg, Donald P.
year	1986
title	The Light Buffer: A Shadow-Testing Accelerator
source	IEEE Computer Graphics and Applications. September, 1986. vol. 6: pp. 6-16 : col. ill. includes bibliography
summary	In one area of computer graphics, realistic image synthesis, the ultimate goal is to produce a picture indistinguishable from a photograph of a real environment. A particularly powerful technique for simulating light reflection - an important element in creating this realism - is called ray tracing. This method produces images of excellent quality, but suffers from lengthy computation time that limits its practical use. This article presents a new method to reduce shadow testing time during ray tracing. The technique involves generating light buffers, each of which partitions the environment with respect to an individual light source. These partition descriptions are then used during shadow testing to quickly determine a small subset of objects that may have to be tested for intersection. The results of timing tests illustrate the beneficial performance of these techniques. The tests compare the standard ray-tracing algorithm to light buffers of varying resolution
keywords	realism, synthesis, ray tracing, algorithms, computer graphics, shadowing
series	CADline
last changed	2003/06/02 13:58

_id	2ceb
authors	Hearn, Donald and Baker, Pauline M.
year	1986
title	Windowing and Clipping -- - Chapter 6
source	Computer Graphics. Englewood Cliffs, NJ.: Prentice Hall, 1986. pp. 123-141 : ill. includes a short bibliography
summary	Applications programs define pictures in a world coordinate system. This can be any Cartesian coordinate system that a user finds convenient. Pictures defined in world coordinates are then mapped by the graphics system into device coordinates. Typically, a graphics package allows a user to specify which area of the picture definition is to be displayed and where it is to be placed on the display device. A single area could be chosen for display, or several areas could be selected. These areas can be placed in separate display locations, or one area can serve as a small insert into a larger area. This transformation process involves operations for translating and scaling selected areas and for deleting picture parts outside the areas. These operations are referred to as windowing and clipping
keywords	clipping, windowing, computer graphics
series	CADline
last changed	2003/06/02 13:58

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