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151.
We present a multiresponse estimation procedure for parameters of systems described by ? = As. The procedure features a generalized Gauss–Newton algorithm for optimizing the determinant criterion, efficient evaluation of the expectation function and its derivatives directly from the reaction network or compartment diagram, automatic determination of starting values, and eficient computational procedures for handling linear constraints on the responses. 相似文献
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Donald Watson 《Journal of Architectural Education》2013,67(4):41-42
Summary of some of the topics covered by the author under the ACSA-AMAX Research Fellowship, which he won in 1967. 相似文献
156.
Donald Barthelme 《Journal of Architectural Education》2013,67(2):47-50
The challenge of understanding the many facets of design has been a central issue in attempting to computationally define design processes and knowledge. The historical progression of computers in design has been characterized by high aspirations repeatedly humbled by the complexity of design problems. Fundamental questions concerning the role and impact of computers in design should be re-examined in light of new developments in Computer-Aided Design (CAD) and Artificial Intelligence (AI), and the progressive understanding of design itself. At the heart of these issues must lie a mutual understanding of the respective traits of design and computation, and the balance of interaction between them.In this paper two avenues, expressed in terms of mappings between design and computation, are explored with the intention of clarifying the relationship between the theories of design and computation. First, the relationship between models of the design process and computational search strategies is explored. Several paradigms (problem solving, puzzle making, and constraint satisfying), which demonstrate a breadth of approaches to modeling design, are presented along with their computational implications. Second, relationships between design knowledge and computational representation schemes are discussed. Emphasis is placed on drawing from cognitive and computational knowledge representation schemes to represent design knowledge. Finally, some thoughts on integrating these design models and knowledge representation schemes into computer systems to assist designers are discussed. 相似文献
157.
J. Donald Hughes 《Landscape Research》2013,38(1):21-31
Landscapes at the edge of the city comprise vast areas that ‘lie fallow’, awaiting future urban development. During this time new landscape values evolve. It is argued that the complexity of urban fringe landscapes is not adequately considered either within landscape research or in the practice of spatial planning. A key to understanding landscapes at the inner urban fringe is to focus on landscape dynamics, and on the interactions between spatial plans and everyday activities. The study is divided into three parts. First, theoretical considerations about landscape dynamics and the character of the inner urban fringe are presented. Thereafter, the relationship between spatial planning and everyday places is analysed in a case-study area at the edge of the city of Malmö in southernmost Sweden. The case study demonstrates the complexity of landscape dynamics at the inner urban fringe, as well as problems regarding the handling of ephemeral and transitory aspects within spatial planning. The study concludes with a discussion concerning the importance of studies of landscape dynamics within landscape research. 相似文献
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Emmanuel U. Nzewi Donald D. Gray Mark H. Houck 《Civil Engineering and Environmental Systems》2013,30(3):132-141
The development and implementation of a Fortran computer program called OGSDP to design a least-cost gravity sanitary sewer system are presented. OGSDP is a model that finds the least-cost design for a non-looping, gravity sanitary sewerage system for a given set of design parameters, costs and lay-out. The final design is the least-cost combination of pipe sizes, upstream and downstream invert elevations (of each pipe) and the corresponding manhole sizes. OGSDP respects most Ten States Standards' (1978) design guidelines. OGSDP determines an initial sewer system design using a heuristic procedure, and then improves the design using discrete dynamic programming with successive approximations to obtain the final least-cost design. It is a practical and efficient tool in the design of sanitary sewer systems. 相似文献
160.
The phenomenon of virtual space is fundamental to the way human beings relate perceptually, behaviorally, and existentially to their world. Virtuality is the presence of what is not literally present, and it thus enables the immanence of building to be annealed to the past and future, analogous form, and hypothetical possibility. In sum, virtuality is synonymous with “architecture” proper, as opposed to building simple. Through the use of gesture, the non-present is made present and given a secret status ruled by a non-classical or “grotesque” order. The principle of our access to the virtual is based on the act of reading, where the movement from the actual to the virtual is simultaneously a spatial and a philosophical transformation. Reading is not simply the translation of phonetic or iconographic characters into their linguistic equivalents, but a restructuring of the space of appearance. The origins and evolution of this “space of reading” are characterized by a distinctive architecture, and the architecture of inhabitable spaces is conditioned by this distinctive architecture: the architecture of reading is the means of reading architecture. 相似文献