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The purpose of this study is to solve the key problem of the residual stress of strip in buckling and deviation during the continuous annealing process (CAP).

Considering the one-to-one correspondence between deformation and residual stress, the strip was divided into multiple elements. To obtain the total deformation of each element, the influence model of some factors on the deformation of steel strip element was established. Then, according to the constitutive equation of residual stress and deformation, and the deformation coordination relation between strip elements, a set of calculation model, which is suitable for residual stress of strip during CAP was established, the model precision was verified by finite element method simulation, and the influences on residual stress of strip were also analyzed.

The weighted calculation of comparison between analytical results and simulation shows that the accuracy of the analytical method is within 10 per cent, which fully meets the requirements.

The different residual stress of steel strip can be displayed quickly and intuitively in the synchronous process segment according to this model, which is of great importance to the prevention of strip buckling and deviation.

This study is concerned with evaluating the performance of different storage policies and tour construction procedures for multi‐command picking using automated storage‐retrieval systems (AS/RS). The AS/RS machine travel time for each storage policy is derived as a function of the shape of the storage area, the number of picking points and the sequencing algorithm used. The combination of these variables yields various solutions to the problem, thus providing a useful guide in designing effective picking systems. The average travel time of the AS/RS in each configuration is calculated by computer simulation in a full factorial experimental design. A subset of the results derived from this study has been successfully implemented in a case study, involving the BMW AG Italy spare parts distribution warehouse.

AFTER cutting oils, rolling oils probably constitute the next largest overall offtake of metalworking oils although the proportions for any individual supplier may be very different, since much of the business is in the hands of specialists and some of the largest companies may do little.

Recent surveys indicate that transportation companies are not utilizing technology in decision making despite growing complexity of transportation systems. This paper aims to present a discrete simulation approach to benchmarking performance measures of terminal operations of less‐than‐truckload (LTL) freight carriers.

The methodology involves design of heuristics for the dock assignment problem and uses discrete event simulation to evaluate performance of the various heuristics.

Intelligent dock assignment for incoming trailers can greatly improve performance of LTL terminals and simulation is an effective tool to determine the effects of various assignments on terminal performance.

The paper introduces a dock assignment heuristic and integrates the tactical level decision‐making process and operational aspects in LTL terminals to evaluate the performance of the system. A case study is used to demonstrate the use of the heuristic and performance improvements.

This paper is concerned with infinite elements for dynamic problems, that is, those which change in time. It is a sequel to our earlier paper on static problems. The paper is in a number of sections. The first is an introduction. In the second the state‐of‐the‐art review of infinite elements is updated. In the third, ‘added mass’ type effects are considered. In the fourth, time dependent problems of the diffusion type, which only involve the first time derivative are considered. Wave problems are considered in the fifth and the necessary radiation conditions for such problems are summarized. Section six deals with dynamic problems of a repetitive nature, that is periodic or harmonic problems. In section seven completely transient problems are dealt with and some fundamental difficulties are noted. Conclusions are drawn in section eight.

Describes a two‐ and, later, a three‐dimensional view of supply chain dynamics within a theoretical framework derived from research carried out in the UK automotive industry. However, the authors believe that the models developed have a far wider applicability than this narrow sectoral and geographic focus. The research has been developed within two research programmes. The first programme, called “LEAP” (lean processing programme), involves Corus (formerly British Steel Strip Products), two steel service centres and six major UK‐based automotive component manufacturers, all linked within a common supply chain. The second programme, called “3DayCar”, involves 20 European industrial sponsors including six automotive manufacturers. Both programmes are supported by the UK Government Innovative Manufacturing Initiative (IMI). Conclusions based on the waves analogy will be applied to a real‐life setting in order to suggest appropriate business strategies to achieving a lean value stream.

The purpose of this study is to improve the global optimization ability of the Tabu search (TS) algorithm, and then improve the calculation efficiency and accuracy of rolling schedule in tandem cold rolling.

A case-based reasoning–Tabu search hybrid algorithm (CBRTS) has been presented. First, the case-based reasoning technology was adopted to obtain high-quality initial solution and then the TS algorithm was used for global optimization.

The optimization effect of CBRTS is compared with that of the traditional TS algorithm, and the analysis result indicates that the CBRTS has a faster convergence rate than TS, and the optimization results are closer to the global optimal. Meanwhile, the rolling schedule calculated by CBRTS is more reasonable, which can increase the production efficiency while giving full play to the capacity of equipment.

A CBRTS hybrid algorithm is presented. The strong dependence of the TS algorithm on the initial solution has been solved. The rolling schedule multi-objective optimization functions are established. The proposed algorithm is applied in a 1,450-mm tandem cold rolling production line. The improved method can reduce about half the iterations compared with the traditional one.

The purpose of this paper is to develop a cost effective ball grid array (BGA) workcell for solder ball attachment.

This paper presents the construction of a low‐cost high‐efficiency automatic ball attachment workcell. In fact, it is an economical means of simultaneous placement of all solder balls on BGA substrates containing multiple BGA units as well as singulated substrates. Common industry problems such as the effect of static charges, the solder ball oxidation, the missing ball, the extra ball, the ball alignment, the deformed ball and, etc. will be addressed and critical issues affecting yield will also be discussed in this paper.

BGA is a popular integrated circuit packaging that is often applied in laptop computers and other handheld electronic devices for the provision of a high‐connection count in a relatively small area. However, the cost of a market available BGA solder ball attachment workcell is very expensive and the flexibility in fitting various customized process is usually low.

The developed workcell cost is about half of the market available machines with similar specifications; the yield achieved is within three sigma confidence interval with competitive output rate. The maintenance and troubleshooting are easy since the machine was developed by the in‐house engineering team.

The lack of reliable and scalable superconducting random access memory (RAM) cells is the main obstacle for full implementation of superconducting rapid single flux quantum(RSFQ) computers. This work points the methodology and the structures that shall be used in future implementation of RSFQ RAM.

A new design for RAM using two ferromagnetic strips in proximity to the superconductor in a RSFQ computer is presented (1). The concept of using a RAM RSFQ cell as a tuneable superconducting qubit is also explored.

Two basic architectures for superconducting RAM cells were developed with integration schemes in two dimensions.

The proposed RAM cells as depicted in Figures 7 and 16 offer smaller size and greater 3 scalability in comparison to other suggested schemes (4), (3), (2), (5).

Currently, the main obstacle in implementation of RSQF computer is lack of reliable RAM cell. RSQF computer shall have potential to take a large fraction of classical supercomputers, as it consumes much less power.

Computation power shall be cheaper when one uses RSQF computers for big data and computational centres. It is a matter of some time.

The publication presents the new design of superconducting RAM cell for use in RSQF computer. The numerical relaxation method is used to solve biharmonic Ginzburg–Landau equation. The analytic approach as a solution of a specified problem is given.