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	9964
authors	Augenbroe, G. and Winkelmann, F.
year	1991
title	Integration of Simulation into the Building Design Process
source	J.A. Clarke, J.W. Mitchell, and R.C. Van de Perre (eds.), Proceedings, Building Simulation '91 IBPSA Conference, pp. 367-374
summary	We describe the need for a joint effort between design researchers and simulation tool developers in formulating procedures and standards for integrating simulation into the building design process. We review and discuss current efforts in the US and Europe in the development of next-generation simulation tools and design integration techniques. In particular, we describe initiatives in object-oriented simulation environments (including the US Energy 'Kernel System, the Swedish Ida system, the UK Energy Kernel System, and the French ZOOM program.) and consider the relationship of these environments to recent R&D initiatives in design integration (the COMBINE project in Europe and the AEDOT project in the US).
series	other
last changed	2003/11/21 15:16

_id	caadria2020_231
id	caadria2020_231
authors	Doe, Robert
year	2020
title	sensMOD - Computational Design through the lens of Henri Lefebvre's Spatial Theory
doi	https://doi.org/10.52842/conf.caadria.2020.1.701
source	D. Holzer, W. Nakapan, A. Globa, I. Koh (eds.), RE: Anthropocene, Design in the Age of Humans - Proceedings of the 25th CAADRIA Conference - Volume 1, Chulalongkorn University, Bangkok, Thailand, 5-6 August 2020, pp. 701-710
summary	Spatial productivity is the first of the elements comprising sensMOD, a student elective that implemented a methodology addressing the exigent need of our time for transformation in the architecture, engineering and construction (AEC) sector. The second and third elements of sensMOD are parts and interaction which focus attention on the nature of complexity and connectivity in our networked world. The paper proposes a methodology that was used to guide the teaching of an elective for third year architecture students at a UK university. Its wider purpose is to contribute to discussion concerning the dysfunctional state of an AEC sector that needs to consider its productivity as projections of wider networks of resource and energy relationships. Henri Lefebvre's spatial theory (1991) guides the narrative and formulation of sensMOD.
keywords	computational design; spatial productivity; modularity; interaction design
series	CAADRIA
email
last changed	2022/06/07 07:55

_id	6f3e
authors	Eastman, Charles M. and Lang, Jurg
year	1991
title	Experiments in Architectural Design Development Using CAD
source	Computer Aided Architectural Design Futures: Education, Research, Applications [CAAD Futures ‘91 Conference Proceedings / ISBN 3-528-08821-4] Zürich (Switzerland), July 1991, pp. 49-64
summary	The need to explore development techniques in computer-based design is reviewed. Some premises are given for design development using computers, including integrating multiple representations, the use of object-based modeling and the importance of visual analysis and 3-D modeling. We then present techniques used in a UCLA design studio that explored methods of computer-based design development based on these premises. The two main methods used were hierarchical object structures and multi-representational coordination. They were applied using conventional CAD systems. Some lessons learned from this class are reviewed.
series	CAAD Futures
email
last changed	2003/05/16 20:58

_id	ecaade2007_073
id	ecaade2007_073
authors	Francis, Sabu
year	2007
title	Web Based Collaborative Architectural Practice Using a Fractal System
doi	https://doi.org/10.52842/conf.ecaade.2007.727
source	Predicting the Future [25th eCAADe Conference Proceedings / ISBN 978-0-9541183-6-5] Frankfurt am Main (Germany) 26-29 September 2007, pp. 727-734
summary	I have been working on an architecture representation system in India since 1991; that markedly deviates from the need of traditional drawings as we know. Over three million square feet of work has been done that took advantage of this system as it was being developed. The system has now matured sufficiently to be put into practice as a comprehensive architectural system of practice. It takes advantage of creation of just-in-time dynamic multi-organizations that can get formed (and dismantled) over the Internet on a project to project basis. The raison d’être of the representation system is that it would expose the “source-code” (metaphorically) of any work of architecture to stakeholders, much the same way as an open-source software project exposes the internal representation to fellow developers. I believe the design of architecture must go through an “open source” process in order to produce socially responsible designs. Such a stance is explained in this paper. The paper also explains the system in detail; its mathematical basis and justifies the need for such an approach. It also explores how a collaborative practice can be put into place using the system in the context of Internet technologies.
keywords	Collaborative practice, fractals, representation system
series	eCAADe
email
last changed	2022/06/07 07:50

_id	673a
authors	Fukuda, T., Nagahama, R. and Sasada, T.
year	1997
title	Networked Interactive 3-D design System for Collaboration
doi	https://doi.org/10.52842/conf.caadria.1997.429
source	CAADRIA ‘97 [Proceedings of the Second Conference on Computer Aided Architectural Design Research in Asia / ISBN 957-575-057-8] Taiwan 17-19 April 1997, pp. 429-437
summary	The concept of ODE (Open Design Environment) and corresponding system were presented in 1991. Then the new concept of NODE. which is networked version of ODE. was generated to make wide area collaboration in 1994. The aim of our research is to facilitate the collaboration among the various people involved in the design process of an urban or architectural project. This includes various designers and engineers, the client and the citizens who may be affected by such a project. With the new technologies of hyper medium, network, and component architecture, we have developed NODE system and applied in practical use of the collaboration among the various people. This study emphasizes the interactive 3-D design tool of NODE which is able to make realistic and realtime presentation with interactive interface. In recent years, ProjectFolder of NODE system, which is a case including documents, plans, and tools to proceed project., is created in the World Wide Web (WWW) and makes hyper links between a 3-D object and a text, an image. and other digital data.
series	CAADRIA
email
last changed	2022/06/07 07:50

_id	728f
authors	Gross, Mark D.
year	1991
title	Grids in Design and CAD
doi	https://doi.org/10.52842/conf.acadia.1991.033
source	Reality and Virtual Reality [ACADIA Conference Proceedings / ISBN 1-880250-00-4] Los Angeles (California - USA) October 1991, pp. 33-43
summary	The grid is a useful device for expressing design rules about the placement of elements in a layout. By expressing position rules for elements in relation to a grid, a designer can systematically organize decisions in a layout design problem. Grids and placement rules offer a discipline that can help a designer work effectively to lay out complex designs, and it can also facilitate group design work. Unfortunately, computer supported drawing systems often cannot support this way of working because they lack a sufficiently rich implementation of grids. The Grid Manager module of the CoDraw program shows enhancements useful for architectural Computer Assisted Design. These enhancements would enable more effective ways of using the computer as a design tool.
series	ACADIA
email
last changed	2022/06/07 07:51

_id	01c8
authors	Gross, Mark D.
year	1991
title	Programming 2-Way Constraints in CODRAW
source	1991. [8] p. : ill. includes bibliography
summary	Constraints based drawing programs require users to understand and manage relationships between drawing elements. By establishing constraint relationship among elements the user effectively programs the drawing's behavior. This programming task requires a more sophisticated visual interface than conventional drawing programs provide. Users must have available - in a convenient format - information about the structure of the constraints that determine the drawing's interactive edit behavior. This format must support editing and debugging. CoDraw is a constraint based drawing program that can be interactively extended by its users. This paper describes the CoDraw program and its programming interface
keywords	constraints, drafting, user interface
series	CADline
last changed	2003/06/02 10:24

_id	39e0
id	39e0
authors	Jablonski, Allen D.
year	1991
title	Integrated Component-based Computer Design Modeling System: The Implications of Control Parameters on the Design Process
source	New Jersey Institute of Technology, Newark, NJ Graduate Thesis - Master's Program College of Architecture
summary	The design process is dependent on a clear order of integrating and managing all of the control parameters that impact on a building's design. All component elements of a building must be defined by their: Physical and functional relations; Quantitative and calculable properties; Component and/or system functions. This requires a means of representation to depict a model of a building that can be viewed and interpreted by a variety of interested parties. These parties need different types of representation to address their individual control parameters, as each component instance has specific implications on all of the control parameters. Representations are prepared for periodic design review either manually through hand-drawn graphics and handcrafted models; or with the aid of computer aided design programs. Computer programs can profoundly increase the speed and accuracy of the process', as well as provide a level of integration, graphic representation and simulation, untenable through a manual process. By maintaining a single control model in an Integrated Component-based Computer Design Modeling System (ICCDMS), interested parties could access the design model at any point during the process. Each party could either: 1. Analyze individual components, or constraints of the model, for interferences against parameters within that party's control; or 2. Explore design alternatives to modify the model, and verify the integration of the components or functions, within the design model, as allowable in relation to other control parameters.
keywords	Architectural Design; Data Processing
series	thesis:MSc
type	extended abstract
email
more	http://www.library.njit.edu/etd/1990s/1990/njit-etd1990-005/njit-etd1990-005.html
last changed	2006/09/25 09:04

_id	e7fb
authors	Leclercq, Pierre
year	1991
title	Students in Efficient Energy Management
doi	https://doi.org/10.52842/conf.ecaade.1991.x.e7o
source	Experiences with CAAD in Education and Practice [eCAADe Conference Proceedings] Munich (Germany) 17-19 October 1991
summary	The LEMA presents Strategy II, the new version of his CAL software in thermal design of building. Based on his latest experiences using the first prototypes, the present programme provides an complete human interface and interesting tools for decision taking. A first educational experience with this software is described. Strategy II has been studied in 1990 by two twin teams: one is the LEMA (Laboratoire d'Etudes Méthodologiques Architecturales) and the other one is the CTE (Centre des Technologies de l'Education), parts of the University of Liège, in Belgium.
series	eCAADe
last changed	2022/06/07 07:50

_id	c65f
authors	Littlefair, P.J.
year	1991
title	Site Layout Planning for Daylight and Sunlight
source	Building Research Establishment Report
summary	This guide gives advice on site layout planning to achieve good sunlight and daylight within buildings and adjacent open spaces such as gardens. It includes methods that allow for the calculation of sunlight or daylight levels at 4 different latitudes within the UK and for different times of the year. An additional section discusses the subject of site layout and design for obtaining maximum solar energy. This guide supersedes the original Department of the Environment document Sunlight and Daylight. BRE 209 has sections for the following:- * Light from the Sky. * New development. * Existing Buildings. * Adjoining development land. * Sunlighting. * New development. * Existing Buildings. * Gardens & open spaces. * Passive solar design. * Other issues. * View. * Privacy. * Security. * Access. * Enclosure. * Microclimate. * Solar dazzle. * Appendix A. Indicators to calculate access to sunlight, skylight and solar radiation. * Appendix B. A waldram diagram to calculate vertical sky component. * Appendix C. Interior daylighting recommendations. * Appendix D. Plotting the no-sky line. * Appendix E. Rights to light. * Appendix F. Setting alternative target values for skylight access. * Appendix G. Calculation of sun on the ground. * Appendix H. Definitions.
series	report
last changed	2003/04/23 15:14

_id	7508
authors	Montgomery, D.C.
year	1991
title	Design and Analysis of Experiments
source	John Wiley, Chichester
summary	Learn How to Achieve Optimal Industrial Experimentation Through four editions, Douglas Montgomery has provided statisticians, engineers, scientists, and managers with the most effective approach for learning how to design, conduct, and analyze experiments that optimize performance in products and processes. Now, in this fully revised and enhanced Fifth Edition, Montgomery has improved his best-selling text by focusing even more sharply on factorial and fractional factorial design and presenting new analysis techniques (including the generalized linear model). There is also expanded coverage of experiments with random factors, response surface methods, experiments with mixtures, and methods for process robustness studies. The book also illustrates two of today's most powerful software tools for experimental design: Design-Expert(r) and Minitab(r). Throughout the text, You'll find output from these two programs, along with detailed discussion on how computers are currently used in the analysis and design of experiments. You'll also learn how to use statistically designed experiments to: * Obtain information for characterization and optimization of systems * Improve manufacturing processes * Design and develop new processes and products * Evaluate material alternatives in product design * Improve the field performance, reliability, and manufacturing aspects of products * Learn how to conduct experiments effectively and efficiently Other important textbook features: * Student version of Design-Expert(r) software is available. * Web site (www.wiley.com/college/montgomery) offers supplemental text material for each chapter, a sample syllabus, and sample student projects from the author's Design of Experiments course at Arizona State University.
series	other
last changed	2003/04/23 15:14

_id	ga0010
id	ga0010
authors	Moroni, A., Zuben, F. Von and Manzolli, J.
year	2000
title	ArTbitrariness in Music
source	International Conference on Generative Art
summary	Evolution is now considered not only powerful enough to bring about the biological entities as complex as humans and conciousness, but also useful in simulation to create algorithms and structures of higher levels of complexity than could easily be built by design. In the context of artistic domains, the process of human-machine interaction is analyzed as a good framework to explore creativity and to produce results that could not be obtained without this interaction. When evolutionary computation and other computational intelligence methodologies are involved, every attempt to improve aesthetic judgement we denote as ArTbitrariness, and is interpreted as an interactive iterative optimization process. ArTbitrariness is also suggested as an effective way to produce art through an efficient manipulation of information and a proper use of computational creativity to increase the complexity of the results without neglecting the aesthetic aspects [Moroni et al., 2000]. Our emphasis will be in an approach to interactive music composition. The problem of computer generation of musical material has received extensive attention and a subclass of the field of algorithmic composition includes those applications which use the computer as something in between an instrument, in which a user "plays" through the application's interface, and a compositional aid, which a user experiments with in order to generate stimulating and varying musical material. This approach was adopted in Vox Populi, a hybrid made up of an instrument and a compositional environment. Differently from other systems found in genetic algorithms or evolutionary computation, in which people have to listen to and judge the musical items, Vox Populi uses the computer and the mouse as real-time music controllers, acting as a new interactive computer-based musical instrument. The interface is designed to be flexible for the user to modify the music being generated. It explores evolutionary computation in the context of algorithmic composition and provides a graphical interface that allows to modify the tonal center and the voice range, changing the evolution of the music by using the mouse[Moroni et al., 1999]. A piece of music consists of several sets of musical material manipulated and exposed to the listener, for example pitches, harmonies, rhythms, timbres, etc. They are composed of a finite number of elements and basically, the aim of a composer is to organize those elements in an esthetic way. Modeling a piece as a dynamic system implies a view in which the composer draws trajectories or orbits using the elements of each set [Manzolli, 1991]. Nonlinear iterative mappings are associated with interface controls. In the next page two examples of nonlinear iterative mappings with their resulting musical pieces are shown.The mappings may give rise to attractors, defined as geometric figures that represent the set of stationary states of a non-linear dynamic system, or simply trajectories to which the system is attracted. The relevance of this approach goes beyond music applications per se. Computer music systems that are built on the basis of a solid theory can be coherently embedded into multimedia environments. The richness and specialty of the music domain are likely to initiate new thinking and ideas, which will have an impact on areas such as knowledge representation and planning, and on the design of visual formalisms and human-computer interfaces in general. Above and bellow, Vox Populi interface is depicted, showing two nonlinear iterative mappings with their resulting musical pieces. References [Manzolli, 1991] J. Manzolli. Harmonic Strange Attractors, CEM BULLETIN, Vol. 2, No. 2, 4 -- 7, 1991. [Moroni et al., 1999] Moroni, J. Manzolli, F. Von Zuben, R. Gudwin. Evolutionary Computation applied to Algorithmic Composition, Proceedings of CEC99 - IEEE International Conference on Evolutionary Computation, Washington D. C., p. 807 -- 811,1999. [Moroni et al., 2000] Moroni, A., Von Zuben, F. and Manzolli, J. ArTbitration, Las Vegas, USA: Proceedings of the 2000 Genetic and Evolutionary Computation Conference Workshop Program – GECCO, 143 -- 145, 2000.
series	other
email
more	http://www.generativeart.com/
last changed	2003/08/07 17:25

_id	3105
authors	Novak, T.P., Hoffman, D.L., and Yung, Y.-F.
year	1996
title	Modeling the structure of the flow experience
source	INFORMS Marketing Science and the Internet Mini-Conference, MIT
summary	The flow construct (Csikszentmihalyi 1977) has recently been proposed by Hoffman and Novak (1996) as essential to understanding consumer navigation behavior in online environments such as the World Wide Web. Previous researchers (e.g. Csikszentmihalyi 1990; Ghani, Supnick and Rooney 1991; Trevino and Webster 1992; Webster, Trevino and Ryan 1993) have noted that flow is a useful construct for describing more general human-computer interactions. Hoffman and Novak define flow as the state occurring during network navigation which is: 1) characterized by a seamless sequence of responses facilitated by machine interactivity, 2) intrinsically enjoyable, 3) accompanied by a loss of self-consciousness, and 4) selfreinforcing." To experience flow while engaged in an activity, consumers must perceive a balance between their skills and the challenges of the activity, and both their skills and challenges must be above a critical threshold. Hoffman and Novak (1996) propose that flow has a number of positive consequences from a marketing perspective, including increased consumer learning, exploratory behavior, and positive affect."
series	other
last changed	2003/04/23 15:50

_id	cf2009_poster_43
id	cf2009_poster_43
authors	Oh, Yeonjoo; Ellen Yi-Luen Do, Mark D Gross, and Suguru Ishizaki
year	2009
title	Delivery Types And Communication Modalities In The Flat-Pack Furniture Design Critic
source	T. Tidafi and T. Dorta (eds) Joining Languages Cultures and Visions: CAADFutures 2009 CD-Rom
summary	A computer-based design critiquing system analyzes a proposed solution and offers critiques (Robbins 1998). Critiques help designers identify problems as well as opportunities to improve their designs. Compared with human critics, today’s computer-based critiquing systems deliver feedback in quite restricted manner. Most systems provide only negative evaluations in text; whereas studio teachers critique by interpreting the student’s design, introducing new ideas, demonstrating and giving examples, and offering evaluations (Bailey 2004; Uluoglu 2000) using speech, writing, and drawing to communicate (Anthony 1991; Schön 1983). This article presents a computer-based critiquing system, Flat-pack Furniture Design Critic (FFDC). This system supports multiple delivery types and modalities, adapting the typical system architecture of constraint-based intelligent tutors (Mitrovic et al. 2007).
keywords	Critiquing system, design critiquing
series	CAAD Futures
type	poster
email
last changed	2009/07/08 22:12

_id	6028
authors	Sachs, E., Roberts, A. and Stoops, D.
year	1991
title	3-draw: A tool for designing 3D shapes
source	IEEE Computer Graphics & Applications, pp. 18-25
summary	A fundamentally new type of CAD system for designing shape that is intuitive, easy to use, and powerful is presented. It is based on a paradigm that can be described as designing directly in 3-D. By virtue of two hand-held sensors, designers using 3-Draw to sketch their ideas in the air feel as if they're actually holding and working on objects. Current design practice and related work are reviewed, and current work on 3-Draw is summarized. To capture the flavor of 3-Draw, construction of a sample model of a 12-m yacht is described. 3-Draw's features and data structures are discussed.
series	journal paper
last changed	2003/04/23 15:14

_id	ddss9483
id	ddss9483
authors	Shyi, Gary C.-W. and Huang, Tina S.-T.
year	1994
title	Constructing Three-Dimensional Mental Models from Two-Dimensional Displays
source	Second Design and Decision Support Systems in Architecture & Urban Planning (Vaals, the Netherlands), August 15-19, 1994
summary	In the present study we adopted the tasks and the experimental procedures used in a recent series of study by Cooper (1990, 1991) for the purpose of examining how we utilized two-dimensional information in a line-drawing of visual objects to construct the corresponding three-dimensional mental structure represented by the 2-D displays. We expected that the stimulus materials we used avoided some of the problems that Cooper's stimuli had, and with that we examined the effect of complexity on the process of constructing 3-D models from 2-D displays. Such a manipulation helps to elucidate the difficulties of solving problems that require spatial abilities. We also investigated whether or not providing information representing an object viewed from different standpoints would affect the construction of the object's 3-D model. Some researchers have argued that 3-D models, once constructed, should be viewer-independent or viewpoint-invariant, while others have suggested that 3-D models are affected by the viewpoint of observation. Data pertinent to this issue are presented and discussed.
series	DDSS
last changed	2003/08/07 16:36

_id	90cc
authors	Sohrt, W. and Bruderlin, B.D.
year	1991
title	Interaction with Constraints in 3D Modeling
source	Proceedings of ACM/SIGGRAPH Symposium on Solid Modeling and CADCAM Applications, Austin, TX
summary	The purpose of our research is to simplify and improve the effectiveness of the interactive definition of geometric objects in computer aided geometric modeling. To achieve this goal, two ways of defining geometric objects are combined and interfaced 1) the definition of objects by graphical interaction and 2) the specification of objects by geometric constraints. To demonstrate the practicability of the proposed approach, a geometric modeling system was implemented. In this system, interactive modeling operations automatically generate constraints to maintain the properties intended by their invocatio~ and constraints, in turn, determine the degrees of freedom for further int eractive mouse-controlled modeling operations. A symbolic geometric constraint solver is employed for solvings ystems of constraints. Group hierarchies are utilized for representing dependencies and for locfllzing systems of constraints.
series	other
last changed	2003/04/23 15:50

_id	2c7b
authors	Stenvert, Ronald
year	1993
title	The Vector-drawing as a Means to Unravel Architectural Communication in the Past
doi	https://doi.org/10.52842/conf.ecaade.1993.x.q9a
source	[eCAADe Conference Proceedings] Eindhoven (The Netherlands) 11-13 November 1993
summary	Unlike in painting, in architecture one single person never controls the whole process between conception and realization of a building. Ideas of what the building will eventually look like, have to be conveyed from patron to the actual builders, by way of drawings. Generally the architect is the key-figure in this process of communication of visual ideas. Nowadays many architects design their new buildings by using computers and Computer-Aided (Architectural) Design programs like AutoCad and VersaCAD. Just like traditional drawings, all these computer drawings are in fact vector-drawings; a collection of geometrical primitives like lines, circle segments etc. identified by the coordinates of their end points. Vector-based computer programs can not only be used to design the future, but also as a means to unravel the architectural communication in the past. However, using the computer as an analyzing tool for a better comprehension of the past is not as simple as it seems. Historical data from the past are governed by unique features of date and place. The complexity of the past combined with the straightforwardness of the computer requires a pragmatic and basic approach in which the computer acts as a catalytic agent, enabling the scholar to arrive manually at his own - computer-assisted - conclusions. From this it turns out that only a limited number of projects of a morphological kind are suited to contribute to new knowledge, acquired by the close-reading of the information gained by way of meaningful abstraction. An important problem in this respect is how to obtain the right kind of architectural information. All four major elements of the building process - architect, design, drawing and realization - have their own different and gradually shifting interpretations in the past. This goes especially for the run-of-the-mill architecture which makes up the larger part of the historical urban environment. Starting with the architect, one has to realize that only a very limited part of mainstream architecture was designed by architects. In almost all other cases the role of the patron and the actual builder exceeds that of the architect, even to the extent that they designed buildings themselves. The position of design and drawing as means of communication also changed in the past. Until the middle of the nineteenth century drawings were not the chief means of communication between architects and builders, who got the gist of the design from a model, or, encountering problems, simply asked the architect or supervisor. From the nineteenth century onwards the use of drawings became more common, but almost never represented the building entirely "as built". In 1991 I published my Ph.D. thesis: Constructing the past: computerassisted architectural-historical research: the application of image-processing using the computer and Computer-Aided Design for the study of the urban environment, illustrated by the use of treatises in seventeenth-century architecture (Utrecht 1991). Here, a reconstruction of this historical communication process will be presented on the basis of a project studying the use of the Classical orders as prescribed in various architectural treatises, compared to the use of the orders in a specific group of still existing buildings in The Netherlands dating from the late sixteenth and entire seventeenth century. Comparisons were made by using vector-drawings. Both the illustrations in the the treatises and actual buildings were "translated" into computer-drawings and then analyzed.
series	eCAADe
last changed	2022/06/07 07:50

_id	b5be
authors	Stok, Leon
year	1991
title	Architectural synthesis and optimization of digital systems
source	Eindhoven University of Technology
summary	High level synthesis means going from an functional specification of a digits-system at the algorithmic level to a register transfer level structure. Different appli-cations will ask for different design styles. Despite this diversity in design styles many tasks in the synthesis will be similar. There is no need to write a new synthesis system for each design style. The best way to go seems a decomposition of the high level synthesis problems in several well defined subproblems. How the problem is decomposed depends heavily on a) the type of network architecture chosen, b) the constraints applied to the design and c) on the functional description itself. From this architecture style, the constraints and the functional description a synthesis scheme can be derived.Once this scheme is fixed, algorithms can be chosen which fit into this scheme and solve the subproblems in a fast and, when possible, optimal way. To support such a synthesis philosophy, a framework is needed in which all design information can be stored in a unique way during the various phases of the design process. This asks for a design data base capable of handling all design information with a formally defined interface to all design tools. This thesis gives a formal way to describe both the functional representation, the register transfer level structure and the controller and the relations between all three of them. Special attention has been paid to the efficient representation of mutual exclusive operations and array accesses. The scheduling and allocation problems are defined as mappings between these formal representations. Both the existing synthesis algorithms and the new algorithms described in this thesis fit into this framework. Three new allocation algorithms are presented in this thesis: an algorithm for optimal register allocation in cyclic data flow graphs, an exact polynomial algorithm to do the module allocation and a new scheme to minimize the number of interconnections during all stages of the data path allocation. Cyclic data flow graphs result from high level behavioral descriptions that contain loops. Algorithms for register allocation in high level synthesis published up till now, only considered loop free data flow graphs, When these algorithms are applied to data flow graphs with loops, unnecessary register transfer operations are introduced. A new algorithm is presented that performs a minimal register allocation and eliminates all superfluous register transfer operations. The problem is reformulated as a multicommodity network flow problem for which very efficient solutions exist. Experiments on a benchmark set have shown that in all test cases all register transfers could be eliminated at no increase in register cost. Only heuristic algorithms appeared in literature to solve the module allocation problem. The module allocation problem is usually defined as a clique cover problem on a so-called module allocation graph. It is shown that, under certain conditions, the module allocation graph belongs to the special class of comparability graphs. A polynomial time algorithm can optimally find a clique cover of such a graph. Even when interconnect weights are taken into account, this can be solved exactly. This problem can be transformed into a maximal cost network flow problem, which can be solved exactly in polynomial time. An algorithm is described which solves the module allocation problem with interconnect weights exactly, with a complexity O(kn2), where n is the number of operations In previous research, interconnection was optimized when the module allocation for the operations and the register allocation for the variables already had been done. However, the amount of multiplexing and interconnect are crucial factors to both the delay and the area of a circuit. A new scheme is presented to minimize the number of interconnections during the data path allocation. This scheme first groups all values based on their read and write times. Values belonging to the same group can share a register file. This minimizes the number of data transfers with different sources and destinations. Secondly, registers are allocated for each group separately. Finally the interconnect allocation is done. During the interconnect allocation, the module allocation is determined. The value grouping is based on edge coloring algorithms providing a sharp upper bound on the number of colors needed two techniques: splitting read and write phases of values and introducing serial (re-)write operations for the same value, make that even more efficient exact edge coloring algorithms can be used. It is shown that when variables are grouped into register files and operations are assigned to modules during the interconnection minimization, significant savings (20%) can be obtained in the number of local interconnections and the amount of global interconnect, at the expense of only slightly more register area.
keywords	Digital Systems; Digital Systems
series	thesis:PhD
email
last changed	2003/02/12 22:37

_id	80ce
authors	Turner, R., Balaguer, F., Gobbetti, E. and Thalmann, D.
year	1991
title	Interactive Scene Walkthrough Using a Physically-Based Virtual Camera
source	Computer Aided Architectural Design Futures: Education, Research, Applications [CAAD Futures ‘91 Conference Proceedings / ISBN 3-528-08821-4] Zürich (Switzerland), July 1991, pp. 511-520
summary	One of the most powerful results of recent advances in graphics hardware is the ability of a computer user to interactively explore a virtual building or landscape. The newest threedimensional input devices, together with high speed 3D graphics workstations, make it possible to view and move through a 3D scene by interactively controlling the motion of a virtual camera. In this paper, we describe how natural and intuitive control of building walkthrough can be achieved by using a physically-based model of the virtual camera's behavior. Using the laws of classical mechanics to create an abstract physical model of the camera, we then simulate the virtual camera motion in real time in response toforce data from the various 3D input devices (e.g. the Spaceball and Polhemus 3Space Digitizer). The resulting interactive behavior of the model is determined by several physical parameters such as mass, moment of inertia, and various friction coefficients which can all be varied interactively, and by constraints on the camera's degrees of freedom. This allows us to explore a continuous range of physically-based metaphors for controlling the camera motion. We present the results of experiments using several of these metaphors for virtual camera motion and describe the effects of the various physical parameters.
series	CAAD Futures
last changed	1999/04/07 12:03

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