Model-based computer-aided design environment for operational design

A number of automated reasoning systems find their basis in process control engineering. These programs are often model-based and use individual frames to represent component functionality. This representation scheme allows the process system to be dynamically monitored and controlled as the reasoning system need only simulate the behavior of the modeled system while comparing its behavior to real-time data. The knowledge acquisition task required for the construction of knowledge bases for these systems is formidable because of the necessity of accurately modeling hundreds of physical devices. We discuss a novel approach to the capture of this component knowledge entitled automated knowledge generation (AKG) that utilizes constraint mechanisms predicated on physical behavior of devices for the propagation of truth through the component model base. A basic objective has been to construct a complete knowledge base for a model-based reasoning system from information that resides in computer-aided design (CAD) databases. If CAD has been used in the design of a process control system, then structural information relating the components will be available and can be utilized for the knowledge acquisition function. Relaxation labeling is the constraint-satisfaction method used to resolve the functionality of the network of components. It is shown that the relaxation algorithm used is superior to simple translation schemes.

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Effect of type of practice in a computer-aided design environment in visualizing three-dimensional objects from two-dimensional orthographic projections.

Journal of Applied Psychology ◽

10.1037/0021-9010.81.3.249 ◽

1996 ◽

Vol 81 (3) ◽

pp. 249-260 ◽

Cited By ~ 21

Author(s):

Richard T. Duesbury ◽

Harold F. O'Neil

Keyword(s):

Computer Aided Design ◽

Three Dimensional ◽

Two Dimensional ◽

Design Environment ◽

Three Dimensional Objects ◽

Computer Aided ◽

Aided Design

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Interoperability of Assembly Analysis Applications Through the Use of the Open Assembly Design Environment

Volume 7: 12th Engineering Information Management Symposium ◽

10.1115/detc98/eim-5680 ◽

1998 ◽

Author(s):

Scott Angster ◽

Kevin Lyons ◽

Peter Hart ◽

Sankar Jayaram

Keyword(s):

Virtual Reality ◽

Computer Aided Design ◽

Data Exchange ◽

Systems Design ◽

Design Tools ◽

Design Environment ◽

Assembly Design ◽

Computer Aided ◽

Design Systems ◽

Aided Design

Abstract The emergence of high performance computing has opened up new avenues for the design and analysis community. Integrated Product/Process Design techniques are allowing multi-functional teams to simultaneously optimize the design of a product. These techniques can be inhibited, however, due to software integration and data exchange issues. The work outlined in this paper focuses on these issues as they relate to the design and analysis of electro-mechanical assemblies. The first effort of this work is the creation of an open environment, called the Open Assembly Design Environment. The goal of this environment is to integrate the otherwise disparate assembly design tools using a central control system and a common set of data. These design tools include virtual reality based design systems, computer-aided design systems, design for assembly systems and process planning systems. This paper outlines the overall goals of the project, presents the architecture designed for the system, describes the interfaces developed to integrate the systems, and discusses the data representation requirements for a system integrating a virtual reality system with computer-aided design systems.

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Computer-aided design/engineering of bearing systems using the Dempster-Shafer theory

Artificial intelligence for engineering design analysis and manufacturing ◽

10.1017/s0890060400002043 ◽

1995 ◽

Vol 9 (1) ◽

pp. 1-11 ◽

Cited By ~ 9

Author(s):

A.C. Butler ◽

F. Sadeghi ◽

S.S. Rao ◽

S.R. LeClair

Keyword(s):

Expert System ◽

Computer Aided Design ◽

Professional Judgment ◽

Design Engineering ◽

Design Environment ◽

Dempster Shafer Theory ◽

Computer Aided ◽

Shafer Theory ◽

Aided Design ◽

Symbolic Approach

AbstractResearch in computer-aided design/engineering (CAD/E) has focused on enhancing the capability of computer systems in a design environment, and this work has continued in this trend by illustrating the use of the Dempster-Shafer theory to expand the computer’s role in a CAD/E environment. An expert system was created using Dempster-Shafer methods that effectively modeled the professional judgment of a skilled tribologist in the selection of rolling element bearings. A qualitative and symbolic approach was used, but access to simple quantitative models was provided to the expert system shell. Although there has been significant discussion in the literature regarding modification/improvement of the Dempster-Shafer theory, Shafer’s theories were found adequate in all respects for replicating the expert’s judgment. However, an understanding of the basic theory is required for interpreting the results.

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