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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Hits 1 to 20 of 220

_id 86c1
authors Shih, Shen-Guan
year 1991
title Case-based Representation and Adaptation in Design
source Computer Aided Architectural Design Futures: Education, Research, Applications [CAAD Futures ‘91 Conference Proceedings / ISBN 3-528-08821-4] Zürich (Switzerland), July 1991, pp. 301-312
summary By attempting to model the raw memory of experts, case-based reasoning is distinguished from traditional expert systems, which compile experts' knowledge into rules before new problems are given. A case-based reasoning system processes new problems with the most similar prior experiences available, and adapts the prior solutions to solve new problems. Case-based representation, of design knowledge utilizes the desirable features of the selected case as syntax rules to adapt the case to a new context. As a central issue of the paper, three types of adaptation aimed at topological modifications are described. The first type - casebased search - can be viewed as a localized search process. It follows the syntactical structure of the case to search for variations which provide the required functionality. Regarding the complexity of computation, it is recognized that when a context sensitive grammar is used to describe the desirable features, the search process become intractable. The second type of adaptation can be viewed as a process of self-organization, in which context-sensitive grammars play an essential role. Evaluations have to be simulated by local interaction among design primitives. The third type is called direct transduction. A case is translated directly to another structure according to its syntax by some translation functions. A direct transduction is not necessarily a composition of design operators and thus, a crosscontextual mapping is possible. As a perspective use of these adaptation methods, a CAD system which provides designers with the ability to modify the syntactical structure of a group of design elements, according to some concerned semantics, would support designers better than current CAD systems.
series CAAD Futures
last changed 1999/04/07 12:03

_id f9bd
authors Amor, R.W.
year 1991
title ICAtect: Integrating Design Tools for Preliminary Architectural Design
source Wellington, New Zealand: Computer Science Department, Victoria University
summary ICAtect is a knowledge based system that provides an interface between expert systems, simulation packages and CAD systems used for preliminary architectural design. This thesis describes its structure and development.The principal work discussed in this thesis involves the formulation of a method for representing a building. This is developed through an examination of a number of design tools used in architectural design, and the ways in which each of these describe a building.Methods of enabling data to be transferred between design tools are explored. A Common Building Model (CBM), forming the core of the ICAtect system, is developed to represent the design tools knowledge of a building. This model covers the range of knowledge required by a large set of disparate design tools used by architects at the initial design stage.Standard methods of integrating information from the tools were examined, but required augmentation to encompass the unusual constraints found in some of the design tools. The integration of the design tools and the CBM is discussed in detail, with example methods developed for each type of design tool. These example methods provide a successful way of moving information between the different representations. Some problems with mapping data between very different representations were encountered in this process, and the solutions or ideas for remedies are detailed. A model for control and use of ICAtect is developed in the thesis, and the extensions to enable a graphical user interface are discussed.The methods developed in this thesis demonstrate the feasibility of an integrated system of this nature, while the discussion of future work indicates the scope and potential power of ICAtect.
series other
last changed 2003/04/23 15:14

_id ea6b
authors Boeve, Eddy
year 1991
title Modelling Interaction Tools in the Views Architecture IV. Design Tools
source First Moscow International HCI'91 Workshop Proceedings 1991 p.183
summary Views is a user-interface system in which the user interface is a layer above applications, guaranteeing consistency of the interface, and with a data-layer implementing external object representations, allowing exchange of objects between applications without loss of structure. Although Views offers an architecture to deal with user-interface aspects on a high level, in this report is shown that also low level interaction can be modelled with the architecture provided.
series other
last changed 2002/07/07 16:01

_id 2e56
authors Coyne, Robert Francis
year 1991
title ABLOOS : an evolving hierarchical design framework
source Carnegie Mellon University, Department of Architecture
summary The research reported in this thesis develops an approach toward a more effective use of hierarchical decomposition in computational design systems. The approach is based on providing designers a convenient interactive means to specify and experiment with the decompositional structure of design problems, rather than having decompositions pre-specified and encoded in the design system. Following this approach, a flexible decomposition capability is combined with an underlying design method to form the basis for an extensible and evolving framework for cooperative (humdcomputer) design. As a testbed for this approach, the ABLOOS framework for layout design is designed and constructed as a hierarchical extension of LOOS.’The framework enables a layout task to be hierarchically decomposed, and for the LOOS methodology to be applied recursively to layout subtasks at appropriate levels of abstraction within the hierarchy; layout solutions for the subtasks are then recomposed to achieve an overall solution, Research results thus far are promising: ABLOOS has produced high quality solutions for a class of industrial layout design tasks (an analog power board layout with 60 components that have multiple complex constraints on their placement); the adaptability of the framework across domains and disciplines has been demonstrated; and, further development of ABLOOS is underway including its extension to layouts in 2 1/2D space and truly 3D arrangements. The contribution of this work is in demonstrating an effective, flexible and extensible capability for hierarchical decomposition in design. It has also produced a more comprehensive layout system that can serve as a foundation for the further investigation of hierarchical decomposition in a variety of design domains.
series thesis:PhD
last changed 2003/02/12 22:37

_id ga0024
id ga0024
authors Ferrara, Paolo and Foglia, Gabriele
year 2000
title TEAnO or the computer assisted generation of manufactured aesthetic goods seen as a constrained flux of technological unconsciousness
source International Conference on Generative Art
summary TEAnO (Telematica, Elettronica, Analisi nell'Opificio) was born in Florence, in 1991, at the age of 8, being the direct consequence of years of attempts by a group of computer science professionals to use the digital computers technology to find a sustainable match among creation, generation (or re-creation) and recreation, the three basic keywords underlying the concept of “Littérature potentielle” deployed by Oulipo in France and Oplepo in Italy (see “La Littérature potentielle (Créations Re-créations Récréations) published in France by Gallimard in 1973). During the last decade, TEAnO has been involving in the generation of “artistic goods” in aesthetic domains such as literature, music, theatre and painting. In all those artefacts in the computer plays a twofold role: it is often a tool to generate the good (e.g. an editor to compose palindrome sonnets of to generate antonymic music) and, sometimes it is the medium that makes the fruition of the good possible (e.g. the generator of passages of definition literature). In that sense such artefacts can actually be considered as “manufactured” goods. A great part of such creation and re-creation work has been based upon a rather small number of generation constraints borrowed from Oulipo, deeply stressed by the use of the digital computer massive combinatory power: S+n, edge extraction, phonetic manipulation, re-writing of well known masterpieces, random generation of plots, etc. Regardless this apparently simple underlying generation mechanisms, the systematic use of computer based tools, as weel the analysis of the produced results, has been the way to highlight two findings which can significantly affect the practice of computer based generation of aesthetic goods: ? the deep structure of an aesthetic work persists even through the more “desctructive” manipulations, (such as the antonymic transformation of the melody and lyrics of a music work) and become evident as a sort of profound, earliest and distinctive constraint; ? the intensive flux of computer generated “raw” material seems to confirm and to bring to our attention the existence of what Walter Benjamin indicated as the different way in which the nature talk to a camera and to our eye, and Franco Vaccari called “technological unconsciousness”. Essential references R. Campagnoli, Y. Hersant, “Oulipo La letteratura potenziale (Creazioni Ri-creazioni Ricreazioni)”, 1985 R. Campagnoli “Oupiliana”, 1995 TEAnO, “Quaderno n. 2 Antologia di letteratura potenziale”, 1996 W. Benjiamin, “Das Kunstwerk im Zeitalter seiner technischen Reprodizierbarkeit”, 1936 F. Vaccari, “Fotografia e inconscio tecnologico”, 1994
series other
more http://www.generativeart.com/
last changed 2003/08/07 17:25

_id diss_hensen
id diss_hensen
authors Hensen, J.L.M.
year 1991
title On the Thermal Interaction of Building Structure and Heating and Ventilating System
source Eindhoven University of Technology
summary In this dissertation, developments in the field of building performance evaluation tools are described. The subject of these tools is the thermal interaction of building structure and heating and ventilating system. The employed technique is computer simulation of the integrated, dynamic system comprising the occupants, the building and its heating and ventilating system. With respect to buildings and the heating and ventilating systems which service them, the practical objective is ensuring thermal comfort while using an optimum amount of fuel. While defining the optimum had to be left for other workers, the issue of thermal comfort is addressed here. The conventional theory of thermal comfort in conditions characteristic for dwellings and offices assumes steady-state conditions. Yet thermal conditions in buildings are seldom steady, due to the thermal interaction between building structure, climate, occupancy, and auxiliary systems. A literature rewiew is presented regarding work on thermal comfort specifically undertaken to examine what fluctuations in indoor climate may be acceptable. From the results, assessment criteria are defined. Although its potentials reach beyond the area of Computer Aided Building Design, a description is given of building and plant energy simulation within the context of the CABD field of technology. Following an account of the present state-of-the-art, the choice for starting from an existing energy simulation environment (ESPR) is justified. The main development areas of this software platform - within the present context - are identified as: fluid flow simulation, plant simulation, and their integration with the building side of the overall problem domain. In the field of fluid flow simulation, a fluid flow network simulation module is described. The module is based on the mass balance approach, and may be operated either in standalone mode or from within the integrated building and plant energy simulation system. The program is capable of predicting pressures and mass flows in a user-defined building / plant network comprising nodes (ie building zones, plant components, etc) and connections (ie air leakages, fans, pipes, ducts, etc), when subjected to flow control (eg thermostatic valves) and / or to transient boundary conditions (eg due to wind). The modelling and simulation techniques employed to predict the dynamic behaviour of the heating and ventilating system, are elaborated. The simultaneous approach of the plant and its associated control is described. The present work involved extensions to the ESPR energy simulation environment with respect to robustness of the program, and with respect to additional plant simulation features, supported plant component models and control features. The coupling of fluid flow, plant side energy and mass, and building side energy simulation into one integrated program is described. It is this "modular-simultaneous" technique for the simulation of combined heat and fluid flow in a building / plant context, which enables an integral approach of the thermal interaction of building structure and heating and ventilating system.

A multi stage verification and validation methodology is described, and its applicability to the present work is demonstrated by a number of examples addressing each successive step of the methodology. A number of imaginary and real world case studies are described to demonstrate application of the present work both in a modelling orientated context and in a building engineering context. Then the general conclusions of the present work are summarized. Next and finally, there are recommendations towards possible future work in the areas of: theory, user interface, software structure, application, and technology transfer.

series thesis:PhD
last changed 2003/12/15 14:43

_id 2d77
authors Korte, Michael
year 1991
title CASOB - Simultaneous Surveying and Drawing
source Experiences with CAAD in Education and Practice [eCAADe Conference Proceedings] Munich (Germany) 17-19 October 1991
doi https://doi.org/10.52842/conf.ecaade.1991.x.t7p
summary Accurate planning and economical building within an existing structure require a complex building analysis based upon detailed scale plans. Work has shown unsatisfactory of measuring tools: (1.) Recording of measurements with meterrule and measuring tape often results in mistakes and wasted time. Since the data is not digitalized the measurements cannot be used by a CAD system. (2.) Commercially available CAD software is made only for new planning but not for planning with an existing structure. Up till now architects who predominantly work with existing structures were not able to take advantage of products in the software- and hardware market which would satisfy their needs. The problems already begin with the search for appropriate tools for the surveying of existing structures and the simplest possible transfer of the data to a CAD System. There is an increased demand for quality surveying of existing structures. In Germany, far more than 60 % of all construction planning is related to existing structures. Due to the special situation in the five new states this percentage will grow significantly. Other countries will find themselves in a similar situation. A large number of precise and analytical surveys of existing structures will be needed in a relative short time. Time pressure and stress factors at construction sites call for quality planning and economical construction which can only be accomplished with reliable and exact surveying of structures. Frustrating experiences in the field have led me to develop systems for the surveying of existing structures. With CASOB (Computer Aided Surveying of Buildings) we have a tool today that simultaneously surveys and creates a CAD compatible drawing.

series eCAADe
last changed 2022/06/07 07:50

_id eae1
authors Mitchell, William J.
year 1991
title Functional Grammars: An Introduction
source Reality and Virtual Reality [ACADIA Conference Proceedings / ISBN 1-880250-00-4] Los Angeles (California - USA) October 1991, pp. 167-176
doi https://doi.org/10.52842/conf.acadia.1991.167
summary A practical design must be realizable using available materials and fabrication processes, and it must meet specified functional requirements; these are necessary (though not always sufficient) conditions for solution of a design problem. It is possible to write shape grammars that produce designs which satisfy these two conditions.
series ACADIA
email
last changed 2022/06/07 07:58

_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 ef46
authors Petrovic, I.
year 1991
title Integrative Knowledge-Based Design Systems : A View
source The Computer Integrated Future, CIB W78 Seminar September, 1991. Unnumbered : ill. includes bibliography.
summary The paper describes a recent project whose objective was to redesign GIMSEX-PERT, an existing architectural knowledge- based design system developed in 1987. Its critical generative problems appeared to be the rigid structure and limited evaluation criteria. The project's outcome is DESTOOLS, based on the 'object-oriented-methodology' inspired by the traditional trial-and-error approach. It includes a set of interchangeable design methods that can be applied interactively by any desired sequence, producing or transforming a GIMS Building System object. Such 'moderately- loose' system structure offers flexibility in use, avoids pitfalls of knowledge-based design systems with rigid structure, and is applicable in design research, education and practice
keywords knowledge base, design, architecture, methods, systems, education, practice, integration, evaluation
series CADline
last changed 2003/06/02 13:58

_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 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 4133
authors Van Nederveenm, G.A. and Tolman, F.P.
year 1991
title Modelling Multiple Views on Buildings
source The Computer Integrated Future, CIB W78 Seminar. September, 1991. Unnumbered : ill. includes a short bibliography
summary The building practice is characterized by its loose organization of the different participants, each of whom performs a specific role in a building project and has a specific view on the building project data. When modelling building information it is useful to base the structure of a building model on these views. This can be done by the use of aspect models. This paper presents an approach in which aspect models are used to store view-specific information. The approach is illustrated with an outline of a building reference model. The building reference model consists of a general kernel and view-dependent aspect models. This model is first worked out for one decomposition level, the space unit level. After that the model is extended with other decomposition levels
keywords product modeling, building, database, integration, construction, practice, management
series CADline
last changed 2003/06/02 13:58

_id e924
authors Willems, P.H., Kuiper, P. and Luiten, G.T. (et al)
year 1991
title A Framework for Evolutionary Information Model Development
source The Computer Integrated Future, CIB W78 Seminar. September, 1991. Unnumbered :ill. includes bibliography
summary Large scale information modelling projects, like the development of ISO/STEP, require a modelling approach that does not develop a new model from scratch, but rather base it on a more generic model which, in turn, is based on an even more abstract model, etc. The resulting structure shows a layered framework. On top of which can be found the most generic concepts and downward the more specific concepts with increased semantics. The benefits of such a model development approach are improvements in: version management, object orientated modelling, concurrent model development, controlled change, standardized interfaces, conformance testing etc. This paper describes an environment which supports the development of a new model out of one or more generic parent models. The generation process consists of two steps. In the first step entities of the parent models can be instanciated while constraining the inherited behavior and introducing new behavior. In fact this process is identical with instanciating run time objects from class templates in the object oriented paradigm. However, in the authors' development environment an important (inherited) property of each entity is self-reproduction. In the second step, therefore, each instance is forced to represent its run time state into some kind of information modelling language specification. Appropriate measures are taken to guarantee that the resulting model will conform the behavior of its parent model(s). The paper demonstrates this approach in a multi-layered example currently being implemented and explores several implementation issues
keywords product modeling, standards, integration, abstraction, OOPS
series CADline
last changed 2003/06/02 13:58

_id 83b4
authors Tan, Milton
year 1991
title Themes for Schemes: Design Creativity as the Conceptualization, Transformation, and Representation of Emergent Forms
source Harvard University, Graduate School of Design
summary Architects, graphic designers, and others frequently develop designs by picking out and transforming subshapes of two-dimensional or three-dimensional shapes. Shape grammars formalize this aspect of design by specifying rules of the form $a /to b$: the left-hand side a describes a type of subshape that may be picked out, while the right-hand side b describes what that type of subshape may become. Designs in the language specified by a shape grammar are derived by recursively applying the shape transformation rules to a starting shape. To apply a shape-transformation rule automatically, a computer system, must have the capacity to recognize instances of the type of subshape specified on the left-hand side of the rule. Sometimes such instances are explicitly input by the designer, and explicitly represented in a data structure: in this case, recognition is a relatively straightforward task. But there may also be 'emergent' instances that were not explicitly input, and are only indirectly represented in the data structure. These emergent instances are potentially numerous, and may be extremely difficult to discover. This thesis focuses on mechanisms for picking out and transforming subshapes. The first three chapters place the issue in its broadest context by arguing that different designers--bringing different knowledge and attitudes to the task--will pick out and pay attention to different subshapes in a drawing. This contention is supported by introducing some of the relevant literature on perception, problem-solving, and creativity. Chapter 4 introduces shape grammars to provide a more formal framework for investigating this topic. Chapter 5 describes the properties and limitations of Topdown--a computer program which supports design by applying the rules of a shape grammar, but does not provide for recognition of emergent subshapes. Chapter 6 introduces ECART, a computer program which supports efficient recognition and transformation of emergent subshapes, and demonstrates how its performance transcends that of Topdown. Examination of the results produced by ECART suggest that a designer's conceptual filter--the repertoire of subshape types that he or she can recognize in a drawing--plays a crucial role in the development of design ideas.  
keywords Computer Graphics; Computer Software; Development
series thesis:PhD
email
last changed 2003/02/12 22:37

_id a1dc
authors Budd, T.
year 1991
title An introduction to Object Oriented programming
source Addison-Wesley
summary In An Introduction to Object-Oriented Programming, Timothy Budd provides a language-independent presentation of object-oriented principles, such as objects, methods, inheritance (including multiple inheritance) and polymorphism. Examples are drawn from several different languages, including (among others) C++, C#, Java, CLOS, Delphi, Eiffel, Objective-C and Smalltalk. By examining many languages, the reader is better able to appreciate the general principles that lie beyond the syntax of the individual languages.
series other
last changed 2003/04/23 15:14

_id eaca
authors Davis, L. (ed.)
year 1991
title Handbook of genetic algorithms
source Van Nostrand Reinhold, New York
summary This book sets out to explain what genetic algorithms are and how they can be used to solve real-world problems. The first objective is tackled by the editor, Lawrence Davis. The remainder of the book is turned over to a series of short review articles by a collection of authors, each explaining how genetic algorithms have been applied to problems in their own specific area of interest. The first part of the book introduces the fundamental genetic algorithm (GA), explains how it has traditionally been designed and implemented and shows how the basic technique may be applied to a very simple numerical optimisation problem. The basic technique is then altered and refined in a number of ways, with the effects of each change being measured by comparison against the performance of the original. In this way, the reader is provided with an uncluttered introduction to the technique and learns to appreciate why certain variants of GA have become more popular than others in the scientific community. Davis stresses that the choice of a suitable representation for the problem in hand is a key step in applying the GA, as is the selection of suitable techniques for generating new solutions from old. He is refreshingly open in admitting that much of the business of adapting the GA to specific problems owes more to art than to science. It is nice to see the terminology associated with this subject explained, with the author stressing that much of the field is still an active area of research. Few assumptions are made about the reader's mathematical background. The second part of the book contains thirteen cameo descriptions of how genetic algorithmic techniques have been, or are being, applied to a diverse range of problems. Thus, one group of authors explains how the technique has been used for modelling arms races between neighbouring countries (a non- linear, dynamical system), while another group describes its use in deciding design trade-offs for military aircraft. My own favourite is a rather charming account of how the GA was applied to a series of scheduling problems. Having attempted something of this sort with Simulated Annealing, I found it refreshing to see the authors highlighting some of the problems that they had encountered, rather than sweeping them under the carpet as is so often done in the scientific literature. The editor points out that there are standard GA tools available for either play or serious development work. Two of these (GENESIS and OOGA) are described in a short, third part of the book. As is so often the case nowadays, it is possible to obtain a diskette containing both systems by sending your Visa card details (or $60) to an address in the USA.
series other
last changed 2003/04/23 15:14

_id ea2f
authors Heisserman, Jeff A.
year 1991
title Generative geometric design and boundary solid grammars
source Carnegie Mellon University, Department of Architecture
summary This thesis explores the automatic generation of solid models based on a grammatical paradigm. It introduces a formalism, boundary solid grammars, for this purpose. In this formalism, a set of geometric rules is applied to an initial solid model to generate a language or family of solids. A rule may match on a portion of the boundary of a solid, and then modify the solid or add new solids. Genesis is presented as an implementation of the formalism. A number of grammars have been constructed to demonstrate the concepts and usefulness of the formalism. These grammars generate simple geometric forms including snodakes, recursive octahedra, “fractal” mountains, and spirals. Another grammar generates stereo lithography support structures. Queen Anne houses have been characterized with a more extensive grammar. Grammars are also being developed to generate housings for small computers and structural designs for high rise buildings. The thesis introduces the unary shape operations and a new paradigm for solid modeling, The unary shape operations take models that may have self-intersections, interpret the models consid- ering the given geometry and face orientations, and produce valid models. Local operations, the unary shape operations, and Boolean operations are used together within a valid modeling scheme. The thesis introduces a new boundary representation for manifold and nonmanifold solids, the generalized split-edge representation. It describes generalized Euler operations which manipulate the topology of the nonmanifold representation. Finally, the thesis presents a form of the Euler- Poincare equation that characterizes the relationship between elements of nonmanifold surfaces of solids.
series thesis:PhD
last changed 2003/02/12 22:37

_id c12b
authors Sakr, Yasser H. and Johnson, Robert E.
year 1991
title Computer-Aided Architectural Design Strategies: One Size Does Not Fit All
source Reality and Virtual Reality [ACADIA Conference Proceedings / ISBN 1-880250-00-4] Los Angeles (California - USA) October 1991, pp. 15-31
doi https://doi.org/10.52842/conf.acadia.1991.015
summary The practice of architecture is in the midst of significant change and an increasingly uncertain future. Socio-economic factors external to the profession are forcing firms to develop new strategies for delivering design services. Overlaying these external changes is the uncertainty resulting from the inevitable introduction of information technology, which is only beginning to have an impact on the profession. Some advocates see the emergence of a new form of design firm -the computerized design firm - as an intelligent organization structured around electronic work groups with powerful computation and communications tools (Catalano 1990). On the other hand, many practitioners still see CADD as an expensive technology whose primary result leads to an increase in overhead costs. But some practitioners and researchers (Coyne, 1991) recognize both the potential and, problems that computer-aided design presents to the profession. This research presents a framework for understanding how changing information technology might be appropriately integrated into the design firm. It argues that design is an increasingly diverse enterprise, and that this diversity must be understood in order to effectively integrate information technology. The study is divided into three sections. The first section develops an overview of major social, economic, and structural changes within the profession. The second section discusses two alternative approaches that have been utilized to integrate information technology into firms. The third part presents a framework for understanding how information technology may have an impact on strategies for structuring and organizing architectural firms.
series ACADIA
last changed 2022/06/07 07:56

_id f14c
authors Sariyildiz, Sevil
year 1991
title Conceptual Design by Means of Islamic-Geometric-Patterns within a CAAD-Environment
source Delft University of Technology
summary The starting point in this research was to develop a 3D grammar theory on top of existing 2D Islamic-geometric-patterns, trying to rescue their fundamental geometry contents to be applied in contemporary architecture without compromising any architectural style. As it is self evident the architectural design process consists of clearly distinct stages namely conceptual design, materialisation and further completion. A this conceptual stage the innovative item of the research deals with pattern grammars on 3D complex geometrical patterns, considering them as polyhedra and polytopes, for their use as an underlayer to a concept design, like architects use 2D rectangular and triangular grids by the conventional way. Handling these complex 3D patterns requires a special environment which is possible with CAAD. Within the CAAD environment, the handling of these complex patterns is easily done by means of 3D tools, because the 3D tools permit the user to make any possible manipulations and geometrical transformations in an easier way in space. To a geometrical patterns, there is some attention paid during the last 50 years by some scholars. The most complex geometrical patterns are highly developed in Islamic architecture because it is forbidden in Muslim religion to use man's portraits or sculptures of human beings in the religious buildings. All these approaches to complex patterns are analysed and studied as 2D elements. The question was how could we consider them in 3rd dimensions and use them instead of 2D underlayer, as 3D underlayers in the conceptual phase of the CAAD design. Pattern grammar is a generally employable aid (underlying pattern) for conceptual and material designs. On the basis of rules of symmetry and substitution, ordering principles have been worked out, which can be used for formal design methods as well as detailing systems (e.g. modular coordination). Through the realization of a pattern grammar a wider range of underlying patterns can be offered and a choice from these can be made in a more fundamental manner. At a subsequent stage the collection of "empty boxes" can be filled with (architectural) elements in such a way that another option is created between either filling up the boxes completely, filling them partly, or filling them in such a way that they overflow. It is self-evident that underlying patterns can also be used for details and decoration in a design. Concerning the materialisation of the concept design, within the 3D CAAD environment, substitution methods are partially developed. Further theoretical developments concerning the materialisation phase constantly backed up through feed-back with specialist matters (such as e.g. by means of expert systems, decision-support systems), must be worked out. As feed-back of the research, the possibilities of the design with 3D patterns have been tested and the procedures are explained. (*) Working with 3D patterns gives a designer more inspirations to develop new ideas and new concepts and gives the opportunity to handle the complexity. (*) The formal, structural and symmetrical qualities of geometrical patterns has a positive influence on the industrialisation of the building components. (*) Working with 3D tools which are able to handle complex geometry have a result because of the accuracy of the information, that there has hardly been a mistake made during the preparation and the assembly of the building components. This has also positive results concerning the financial aspects of the building process.
series thesis:PhD
email
last changed 2003/02/12 22:37

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