PROTOTYPES, RAPID prototyping, COMPUTER integrated manufacturing systems, INDUSTRIAL engineering, MATHEMATICAL models, PRODUCTION planning, and COMPUTER-aided process planning

This paper presents a generative process planning system for parts produced by the rapid prototyping process (i.e. fused deposition modelling-FDM). The proposed process planning involves optimal selection of orientating the model with a proper support structure and then provides an intelligent slicing methodology, such as direct or adaptive, to minimise the built up time, keeping the geometry and cusp height errors in control. Pre- and post-slicing processes have been used to minimise the sliced data error. The Computer Aided Process Planning (CAPP) model has been arranged into five modules: orientation, support structure generation, slicing, path planning and Numerical Control (NC) program generation, and model build up. The CAPP model has been implemented in C language having a unique methodology consisting of 42 simplified steps. The CAPP model has been tested for several examples and shows satisfactory results. [ABSTRACT FROM AUTHOR]

RAPID prototyping, PRODUCTION engineering, MANUFACTURING processes, INDUSTRIAL engineering, POWDER injection molding, MARAGING steel, SINTERING, INJECTION molding of metals, MATERIALS, RESEARCH methodology, and METALLURGICAL research

In this research work, attempts have been made to design, develop and evaluate the performance of mould inserts for injection moulding by using a powder-sintering process. Maraging steel powder, sintering aid and binder are materials used in this proposed development process. Attempts have been made to perform in-depth studies and to apply the powder-sintering process, to eventually produce the final sintered components. In addition, an analysis of the dimensional accuracy of the respective stereolithography master models and an analysis of the sintered specimens during various stages of powder-sintering process have been carried out. The intelligent manufacturing systems (IMS) test part with minor modifications has been used in the evaluation of dimensional accuracy, tolerances, distortion and volumetric variations. The main reason for using this unique geometry is the suitability of its design for injection-moulding processes and tooling. [ABSTRACT FROM AUTHOR]

MANUFACTURING processes, RAPID prototyping, PRODUCTION methods, INDUSTRIAL engineering, ARTIFICIAL intelligence, ARTIFICIAL neural networks, and MANUFACTURES

In an earlier work (Ransing et al . 1995), we represented the causal relationship in a defect-metacause-rootcause form. This representation was perceived to be of considerable importance to the research community as well as industry, as it is applicable to any form of manufacturing process. Based on this representation we proposed 'A Semantically Constrained Bayesian Network' for the diagnostic problems (Lewis and Ransing 1997). In this paper, we develop another popular Artificial Intelligence tool, 'Feedforward Neural Network', for such diagnostic problems. The network is constrained to defect-metacause-rootcause topology and it has been shown that metacause concepts can be successfully associated with the hidden nodes. The errors are calculated at both the output layer and the hidden layer. Although the learning process is based on the back-propagation algorithm with a momentum term, the weight changes would occur at a link connecting a node only if at least one of the nodes connected to it in the preceding layer has non-zero activation. The theoretical analysis of such constrained learning is given and it is shown that the network behaviour is acceptable for the diagnostic problems considered. [ABSTRACT FROM AUTHOR]

MATHEMATICAL optimization, ALGORITHMS, INTEGER programming, OPERATIONS research, INDUSTRIAL engineering, and CUTTING stock problem

The rate at which research ideas can be prototyped is significantly increased when re-useable software components are employed. A mission of the Computational Infrastructure for Operations Research (COIN-OR) initiative is to promote the development and use of re-useable open-source tools for operations research professionals. In this paper, we introduce the COIN-OR initiative and survey recent progress in integer programming that utilizes COIN-OR components. In particular, we present an implementation of an algorithm for finding integer-optimal solutions to a cutting-stock problem. [ABSTRACT FROM AUTHOR]