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The advantages of using a multi‐CPU concurrent computer in solving a steady state free surface seepage problem are studied. The underlying computational task is the solution of a large set of linear equations with a projection operation numerous times. In the study, both Jacobi and SOR iteration methods with projection in a modified alternating iteration scheme are used to solve the problem with varied number of nodes (CPUs) and the timing results are compared between a 32 node Hypercube Concurrent Computer and a VAX 11/780 (single CPU). In addition, the performance and the feasibility of the Hypercube Concurrent Computer are discussed by comparing with the number of nodes used and with the VAX 11/780.

To design a novel hybrid approach to illustrate a reciprocal alignment to integrate future products and technologies. This mixed qualitative-quantitative method aims to optimize the final product portfolio and production technologies alignment in the food industry.

A list of products and technologies is extracted and evaluated by experts employing Market Attractiveness and Ease of Implementations Matrix (MA-EI) for products and attractiveness and technological Capability Matrix (A-C) for technologies. Weights of high-scored alternatives are attained applying the Z-number extension of Best Worst Method (ZBWM). After the product-technology matrix is formed and the alignment scores of each pair are determined by experts. Subsequently, final scores are computed, and a framework is proposed by electing high-ranked products and technology of each cluster to form the aligned product and technology portfolios of a food and hygiene industry company.

By employing an uncertain multicriteria decision-making approach besides product and technology matrices in a food industry corporation, among 40 technology and product, 13 products by 6 technologies are proposed. Thus, only six technology are necessary to manufacture the highly important and effective products.

The combination of product and technology analysis matrixes with an uncertain decision-making approach is considered as a novel approach in this research. Moreover, the distinctness between the present study and other researches is the concurrent unified aspect of product portfolio and technology optimization and its implementation in the planning discussion, especially in the food industry.

A numerical solution to the free boundary problem of three‐dimensional transient seepage through an earth dam with accretion is presented. The numerical model uses a Baiocchi type transformation to extend the unknown solution region to a fixed known region. The initial value problem is then solved by an iterative method of successive over‐relaxation type. A seepage situation of sudden rise of water level on one side of a dam is presented as an example problem. The effects of variation of accretion, effective porosity and hydraulic conductivity are studied.

A fully parallel algorithm for the solution of a finite element system using a MIMD (multiple‐instruction multiple‐data architecture) parallel computer is presented. The formulation includes a simple domain decomposer that automatically divides a finite element mesh into a list of subdomains to guarantee the load balancing. Furthermore, each subdomain is assigned to a processor of a parallel computer and treated as a sub‐finite element system with information exchanged through the interface between two adjacent subdomains. With this new algorithm, these sub‐finite element systems are solved fully parallelly as independent finite element systems, not only the computations of the interior nodes but also the computations of the interface nodes can be executed parallelly. Also, the inherently sequential Gauss‐Seidel and SOR schemes are altered into fully parallel iterative schemes. An implementation of this new scheme on an iPSC/2 D5 Hypercube Concurrent Computer reached an efficiency of more than 100% when compared with the sequential SOR scheme.

To provide an excellent numerical method to simulate an important industrial process – wet chemical etching problem.

A mathematical model describing the wet chemical etching process is formulated in terms of a parabolic variational inequality and a non‐overlapping domain decomposition (DD) method is proposed in the etching region, where a partial differential equation is treated in one sub‐domain, while a variational inequality is considered in the second sub‐domain. A Robin boundary condition with a parameter whose optimal value is to be found is enforced on the common boundary between these two sub‐domains. Finite difference technique with projection and the Crank‐Nicholson scheme for the time discretization are the major numerical tools utilized in this paper.

The proposed numerical method has achieved the best numerical performance for the famous wet chemical etching process among all the numerical schemes applied to this problem. It also shows the great computational power of domain splitting technique.

Lack of parallel supercomputer system limits the authors to perform further numerical tests with extremely large data. This will be done in the future.

This is a very useful paper for the academic researchers and industry engineers who wish to develop more advanced numerical methods to simulate various kinds of industry processes along the research direction from this paper.

This paper provides a new and promising version of DD method in the field of moving boundary problems and offers a practical way to simulate wet chemical etching process for the engineers and scientists in the related field.

Two simple and efficient contour plotting algorithms are presented. The first algorithm is a colour‐fill algorithm. The second algorithm is a colour‐fill algorithm as well as a contour line plotting algorithm. Using adaptive quadtree subdividing and linear interpolation, both algorithms are easy to implement. In addition, the contour plotting for a given mesh can be performed parallelly since plotting the contour of an element is totally independent of any other element.

Presents a review on implementing finite element methods on supercomputers, workstations and PCs and gives main trends in hardware and software developments. An appendix included at the end of the paper presents a bibliography on the subjects retrospectively to 1985 and approximately 1,100 references are listed.

Distributed control is an effective method for controlling and suppressing excessive vibrations of continuous systems. Optimal distributed control for a plate problem is solved utilizing a maximum principle after the introduction of a quadratic index of performance in terms of displacement, velocity and a control force as well as an adjoint variable. The problem is reduced to solving a system of partial differential equations for the state variable and the adjoint variable subjected to boundary, initial and terminal conditions. A numerical algorithm is presented to solve the optimal distributed control problem in the space‐time domain which reduces the computational effort required to solve the initial‐terminal‐boundary value problem. Results obtained for a simply supported, rectangular, thin plate are also presented.

Presents numerical algorithms which easily solve both optimal distributed and optimal boundary control problems in a space‐time domain. Analyses two simple cases of continuous systems. These are the vibrating string and the axially vibrating rod. Using finite difference recurrence schemes, gives numerical results which compare the behaviour of the controlled and uncontrolled systems. Compares the results for special cases in which analytical solutions are obtainable are compared with the results using the general numerical schemes.

The purpose of this paper is to explore the selection of decision-making approaches at manufacturing companies when implementing process innovations.

This study reviews the current understanding of decision structuredness for determining a decision-making approach and conducts a case study based on an interactive research approach at a global manufacturer.

The findings show the correspondence of intuitive, normative and combined intuitive and normative decision-making approaches in relation to varying degrees of equivocality and analyzability. Accordingly, the conditions for determining a decision-making choice when implementing process innovations are revealed.

This study contributes to increased understanding of the combined use of intuitive and normative decision making in production system design.

Empirical data are drawn from two projects in the heavy-vehicle industry. The study describes decisions, from start to finish, and the corresponding decision-making approaches when implementing process innovations. These findings are of value to staff responsible for the design of production systems.

Unlike prior conceptual studies, this study considers normative, intuitive and combined intuitive and normative decision making. In addition, this study extends the current understanding of decision structuredness and discloses the correspondence of decision-making approaches to varying degrees of equivocality and analyzability.