The LexiCon: structuring semantics
Abstract: The ISO/PAS 12006-3:2000 "Framework for object oriented information exchange" provides a metamodel
for structuring data relevant to the construction industry. The LexiCon, developed by STABU, is an
implementation of that model. The LexiCon consists of a set of concepts, grouped into categories according
to 12006-3. Each concept should be defined by a set of other concepts and is placed in a specialization
hierarchy with other concepts of the same category. Ultimately, a set of basic concepts exists, from which
all the other concepts are being derived, but which can only be described by a verbal definition.
The concepts in the LexiCon represent the language of the construction industry. The terms of this
language are extracted from numerous documents on several levels of formality, such as standards,
building codes, specification systems, product information systems, technical dictionaries and classification
systems. From these terms found in external documents concepts are then defined in the LexiCon with
formal definitions. Terms from external documents can be in any human language, thus the LexiCon will be
Putting the concepts in the LexiCon in a specialization hierarchy has been a process of trial and error, so
far. In principal, the number of possible hierarchies is endless, leading to also endless discussions. We are
now trying to use a more systematic approach, based on the idea that, when a concept is defined by a set of
other concepts, there will be a subset of these defining concepts that will dedicate where the described
concept will fit into a hierarchy. A consistent hierarchy will be obtained when the subsets of defining
concepts are subsets of defining concepts on a lower level of that hierarchy. It will then be possible to
reorder the hierarchy into another hierarchy, by using different sets and subsets of defining concepts.
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Cluster: papers of the same cluster (result of machine made clusters)
Class: class.synthesis (0.018068)
class.software development (0.012882)
Sound: read aloud.
Permission to reproduce these documents have been graciously provided by the Aarhus School of Architecture, Denmark. The assistnace of the editor, Prof. Kristian Agger, is gratefully aprecciated.
Y Fang, J Teizer
A Multi-User Virtual 3D Training Environment to Advance Collaboration Among Crane Operator and Ground Personnel in Blind Lifts
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Yaqub Rafiq, Martin Beck, Neill Hughes
INTERACTIVE VISUALISATION AS A POWERFUL DECISION SUPPORT TOOL FOR CONCEPTUAL DESIGN
Abstract: Recent advances in evolutionary computation (EC) have made it possible for researchers to develop decision support tools that to some degree assist designers in decision making. Some of the difficulties with the EC are that they generate a population of alternative solutions to choose from and they are generated in a ‘black box’ mode, where there is little or no user interaction. The research presented in this paper is using an interactive visualisation tool that allows designers to conduct a human-led exploration of the solution space that has been generated by the EC. Multi-disciplinary design team members can interact independently with the system to explore and identify regions of the solution space which best meet their disciplinary objectives. The visualisation tools also allow them to find a common framework for multi-disciplinary design. This research then post-processes the data inside the region of the agreed framework, using a Pareto algorithm, to isolate non-dominated solutions for selection purposes.
Keywords: Evolutionary computation, Visualisation, Conceptual design, Decision making.
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Yaqub Rafiq, Martin Beck, Pieter De Wilde
Interactive visualisation as a tool for interpreting building thermal simulation results
Abstract: During building design there is a growing need to reduce energy usage whilst maintaining the comfort of the occupants. The latter is referred to as ‘thermal comfort’ and can be measured by the extent that the internal tem-perature of the building does not exceed a specified comfort level. Traditionally these two measures of building per-formance are seen as a trade off. Moreover, energy efficient building design is a complex process involving a large number of design variables each of which differentially affect both energy usage and thermal comfort. There is a vast search space to be traversed to find an optimal set of potentially good designs. This coupled with computationally ex-pensive building performance simulation software leads to a problem which is potentially intractable. In the past the authors have used the Interactive Visualisation Clustered Genetic Algorithms (IVCGA) to address some of the com-plexities of multi-disciplinary building design problems. The aim of this paper is to apply the IVCGA to allow the build-ing designer (physicist) to: Firstly discover a set of potential design solutions which meet the design objectives of mini-mal energy usage and maximal thermal comfort individually; Secondly discover a set of potential design solutions which are common to all objectives (mutually inclusive region); Thirdly present a means to understand the impact that particular design variables have upon each objective.
Keywords: genetic algorithms, visualisation, design, thermal simulation
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Zatar W A , Mutsuyoshii H
Logical on-line hybrid computer actuator and quasi-static testing schemes of PC columns
Abstract: A preliminary investigation of the feasibility of employing Prestressed Concrete (PC) for bridge columns in high seismicity area is conducted. Satisfactory observation encouraged the authors to verify the preliminary findings by employing a more logical realistic testing technique. A rational on-line hybrid computer actuator testing scheme of seismically vulnerable structures using multi-directional loading is developed. The scheme is utilized for testing three PC column specimens. The innovative findings verified the superior effectiveness of the idea resulting in its recommendation in the latest Seismic Design Code for Prestressed Concrete Structures, Japan. Moreover, for the sake of clarifying and modelling shear strength degradation of such prestressed bridge columns as their draft ratios increase, specimens with low strength ratios are tested using displacement-controlled quasi-static loading. By analysing the results, an insight of concrete shear strength degradation for PC columns is clarified and modelled.
Keywords: on-line hybrid testing, bridge columns, partially prestressed concrete, quasi-static testing, shear strength, displacement ductility
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