摘要:

Abstract:The user interface for an analysis idealization system is described, which is intended for use by design experts. The interface is part of a system to automatically execute analysis for PDEs (Partial Differential Equations), especially by means of the finite element method, and to control the idealizations used in the analysis. The system is designed to be used with commercial modelers and analysis packages, makes use of geometric, attribute and functional models, and addresses the need for multi‐disciplinary analysis support throughout an evolving design. The basics of X/Xt/Motif programming are explained in order to understand the construction of the user interface, and the interface operations are illustrated with example

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00196.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:When supplying finite element model (FEM) plate bending programs with a full‐range interactive graphical input‐output system several graphical problems have to be solved. How can vectors and matrices be found to describe the topology of a figure defined by drawing lines on the screen? How can the information arrays of finite elements be built up when the mesh is given as a set of lines drawn on a screen? What specialities characterise the visualisation processes, in the case of level line figures, pictures according to three‐dimensional visibility, or unfolded cross‐sections? Solutions to some of the most interesting problems will be introduc

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00197.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:The application of many operational research techniques employed by the railway industry requires as input a data model representing the geometrical, structural and operational characteristics of the railway network in question. However, constructing network models with the conventional methods requires a considerable amount of manual work that involves handling large amounts of both qualitative and predominantly, quantitative information. This paper presents an alternative approach for prototyping, constructing and querying railway models, incorporating interactive computer graphics. The presented approach allows the model builder to carry out the modelling task more quickly and accurately. After reviewing the transportation model building trends of the last decades, the authors present the characteristics of the proposed system, demonstrate its main functions and assess its impact on the efficiency of the modelling task.

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00198.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:Various methods exist for the automatic representation of contour plots, frequently used in civil engineering to show, for example, stress distributions in a field or elevations in a survey map. This paper describes some of the contouring methods that influenced the development of algorithms for automatically contouring data specified on grids. Although many methods have been studied in the contouring field, the development of contour lines through a specified grid system is simple and very effective in the solution of various engineering problems. Specific details will be given on the creation of contour plots on regular grids, since routines to contour data that are scattered may interpolate values of points on a regular grid. Procedures for the creation of a three‐dimensional surface through the contour lines will also be give

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00199.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:Current computer‐aided design (CAD) systems are extremely powerful tools for the development of products in an industrial setting. However, they still leave a lot to be desired when it comes to fulfilling a designer's demands and dreams. We believe that knowledge engineering, or more broadly artificial intelligence (AI), is a promising candidate for providing advanced design environments. This paper proposes assorted techniques from AI—such as logical knowledge representation, naive physics, and commonsense reasoning—as effective means of obtaining such environments.In order to make adept, temporal comments, an architecture machine must have a certain basic understanding of qualities. Though at first primitive, this qualitative appreciation itself would evolve within a value system that is very personal, between a man and a ma

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00200.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:Sewage systems design includes computations and drafting. This paper is about the development of a drawing data file pre‐processor (generator) applied to sewage design. The numerical results are used to generate a file with the description of essential elements to be used in computer aided design (CAD) systems.The files are generated in a neutral data format, aiming at portability among CAD systems. This paper presents computer graphics standardization as a way to draw data file characterizatio

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00201.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:An algorithm to calculate the geometrical data which describe a sloped roof covering a building with polygonal plan is presented here. The plan of the building may be any polygonal, simple or multiplyconnected (that is with interior courtyards). The inclination angle of every dope is separately given and can be different from the others. Therefore most practical cases can be solved using this algorithm, for instance roofs, with equally inclined slopes or with all the ridges at the same height, or shed, ridge, Mansard type, saw tooth, and butterfly roofs.The algorithm provides a separate geometrical description for every slope, which can be readily interpreted by any architectural CAD system. A comprehensive description of the algorithm is included, together with the source code of its implementation in Rocky Mountain BASIC and a set of illustrative examples showing how to solve some complicated cases.

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00202.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract:Scientific visualization is one of the emerging techniques used to represent large multi‐parameter data sets in a comprehensible way. Finite element method, as one of the largely used techniques to simulate the behavior of complex systems, typically produces large amounts of multidimensional data. This paper describes a visualization environment for the analysis of finite element data resulting from the integration of several techniques specifically optimized for the domain problem. In the first part of the paper introductory remarks are given on visualization and simulation. The finite element method is presented in more detail in order to keep the description of the system consistent with the paper. Subsequently, an overview of the logical functionality made available by the system is presented.In the second part of the paper, implemented algorithms dealing with the representation and the visualization of finite element data are detailed. Two different methodologies, together with their underlying algorithms, are considered which serve different purposes in the analysis task and in the dissemination of result

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1993.tb00203.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY