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The magneto-electric effect is very much enhanced in multiferroic composite materials due to the long range ferroic ordering and stress mediated magneto-electric coupling. This opens the possibility for applications of multiferroic composites to advanced magnetic, electric and motion sensors. When the magneto-electric effect is magnetically induced, the simultaneously application of a dc and ac magnetic fields is required. The magneto-electric coupling is strongly dependent on both ac/dc applied fields, the measurement geometry and the material properties. In this paper we demonstrate that the crystallographic texture of the magnetic phase within the multiferroic composite can be used to tune the magneto-electric coupling via the dc bias field. Ni[Fe.sub.2][O.sub.4]/PbZrTi[O.sub.3] bi-layer laminated multiferroic samples with various crystallographic textures of the Ni[Fe.sub.2][O.sub.4] have been investigated. We show almost a 300% reduction in the optimum dc bias magnetic field at which the maximum magneto-electric coupling has been observed. The observed reduction is directly related to the crystallographic texture of the Ni[Fe.sub.2][O.sub.4] component. Index Terms--Crystallographic texture, magneto-electric coupling, magneto-electric sensors, multiferroic composites.

This study evaluates operating policies for offering a near-perfect delivery performance for vital customers in dual resource-constrained (DRC) job shop environments. Prior studies have considered this problem in machine-limited settings, and shown that dispatching rules that help realise a near-perfect delivery performance for vital customers necessarily deteriorate delivery performance for other customers served by the shop. This study extends prior work, and considers additional tools that can be used by managers in DRC shops such as labour flexibility, and assignment rules that incorporate customer-based information to deploy workers to departments containing high-priority jobs. Results show that labour flexibility in conjunction with appropriate decision rules allows for enhanced delivery performance for both vital and normal priority customers. These results hold even under conditions where 80% of the shop's workload is compromised of high-priority orders. [ABSTRACT FROM AUTHOR]

Many authors have expressed concern about the negative influence of accounting systems on operational decision making. Accounting systems take two forms, management accounting and financial accounting, and can be tightly linked through the use of standard costing common to both. However, the functions of these two forms of accounting are quite different: management accounting is focused on monitoring and analysing the effect of management decisions, financial accounting is focused on short-term, external reporting. The concern is that this linkage is drawing operating decision making into a short-term, narrow focus not supportive of the most effective operations. Since there has been very little work on how standard costing systems are actually used in operations, this work is an exploratory look at practice. This study explores whether the use of standard costing systems is actually contingent on environment, as may be appropriate, and whether its use affects decision making in operations. Results of a survey of 110 manufacturing companies suggest that at least some firms use standard cost systems in environments where they may not be suited and that their use may not be consistent with the manufacturing strategy. Also, results indicate that some operations managers base decisions on external financal reporting rather than internal criteria such as inventory turnover, number of defects, or customer delivery. Further, significant differences in report usage are associated with whether or not a firm uses standard costing systems. Overall, these results suggest that financial accounting and standard costing systems are influencing operations decision making and that far better understanding of this potentially wide-ranging influence is needed. [ABSTRACT FROM AUTHOR]

The drum-buffer-rope (DBR) planning and control system is relatively new in the published literature. As such, many issues relating to various operating policies have yet to be resolved. In this paper, we look at three such policies. First we study selected order review/release (ORR) methodologies that have appeared in the published literature to be used as the rope component in DBR. Secondly, we study the impact of lot splitting by breaking process batches into numerous transfer batches. Lastly, the impact of capacity balance between the bottleneck resource and non-bottleneck resources are modelled. A simulation model of an existing V plant that manufactures pliers is constructed. Results indicate that the appropriate choice of each operating policy is a function of the shop performance criteria felt to be important by management. No previous paper has studied the feasibility of using the various ORR methodologies in a DBR environment. We show that the performance of each is dependent on other conditions within the shop. Likewise, the impact of lot splitting has yet to be studied. We found that splitting process batches into smaller transfer batches nearly always improved shop performance criteria. Further, simulation results indicate that shop inventory levels necessary to achieve comparable service levels is a function of the capacity balance between bottlenecks and non-bottlenecks, i.e. capacity slack. As capacity slack increases, thereby reducing capacity balance, shop inventory levels show a corresponding decrease. [ABSTRACT FROM AUTHOR]

The success of the Japanese in the global economy has elicited much interest from both practitioners and academicians. Popular theories suggest that the Japanese do not suffer from the short-term financial focus that plagues many U.S. manufacturers but tend to view decisions based on their long-term consequences. As a result, authors have suggested that the criteria used to assess employee performance in Japan tend to reflect this view. This paper reports the results from eight plants in Japan of five Japanese companies regarding the criteria used to assess employee performance. The types of criteria used at various levels in the management hierarchy as well as the specific criteria used are discussed. Previous studies reported that top level managers were most concerned with non-financial criteria while lower level managers were evaluated by physical type measurements. The results from this study partly contradict these findings in that top-level Japanese managers reported profitability as their most important criteria. [ABSTRACT FROM AUTHOR]