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The purpose of this paper is to propose a novel mathematical model to present the three-dimensional tolerance of a discrete surface and to carry out an approach to analyze the tolerance of an assembly with a discrete surface structure. A discrete surface is a special structure of a large surface base with several discrete elements mounted on it, one, which is widely used in complex electromechanical products.

The geometric features of discrete surfaces are separated and characterized by small displacement torsors according to the spatial relationship of discrete elements. The torsor cluster model is established to characterize the integral feature variation of a discrete surface by integrating the torsor model. The influence and accumulation of the assembly tolerance of a discrete surface are determined by statistical tolerance analysis based on the unified Jacobian-Torsor method.

The effectiveness and superiority of the proposed model in comprehensive tolerance characterization of discrete surfaces are successfully demonstrated by a case study of a phased array antenna. The tolerance is evidently and intuitively computed and expressed based on the torsor cluster model.

The tolerance analysis method proposed requires much time and high computing performance for the calculation of the statistical simulation.

The torsor cluster model achieves the three-dimensional tolerance representation of the discrete surface. The tolerance analysis method based on this model predicts the accumulation of the tolerance of components before their physical assembly.

This paper proposes the torsor cluster as a novel mathematical model to interpret the tolerance of a discrete surface.

The objective of this study is to present a successful strategy to promote Korea as the logistics hub of Northeast Asia. Firstly, we introduce the necessity of a logistic hub strategy for Korea. In order to develop a successful strategy, we consider the 'free trade zone' model of the Netherlands and China. We develop a realistic and suitable model for Korea based on this Jree trade zone' model. Our proposal for a successful logistic hub strategy for Korea is the fulfillment of the following six objectives: 1) security of market accessibility, 2) improvement of the logistic system, 3) improvement of the education system, 4) improvement of the tax system, 5) assurance of labor market flexibility, and 6) development of an appealing living environment for foreigners.

Manufacturers find bottom of the pyramid (BOP) markets challenging to serve due to low margins and highly localized needs. As such, residents in BOP markets often go without products commonly available in developed countries. Going without medical equipment may negatively affect healthcare services. This study develops a supply chain design strategy that supports the production of medical equipment by preserving variety flexibility at low volumes that stands to create new market opportunities for manufacturers and improve healthcare for residents in BOP markets.

The authors introduce a mass-customization model called options-based planning (OBP) which offers a framework to both leverage the efficiencies of high volume production models and provide products that are customized to local market needs. An empirical simulation, grounded in data collected from a large international manufacturer of magnetic resonance imaging (MRI) equipment, illustrates how an OBP production strategy will likely perform under BOP conditions and facilitate the delivery of healthcare equipment to BOP markets.

OBP provides a means for manufacturers to provide the customization necessary to serve fragmented BOP markets, while enabling higher production volume to make serving these markets more feasible. The empirical simulation reveals the relative benefits of OBP under conditions of forecast uncertainty, product complexity (number of design parameters) and different levels of responsiveness.

Increased access to modern medical equipment should improve healthcare outcomes for consumers in BOP markets.

The MRI context in BOP markets serves to illustrate the value of the OBP model for manufacturers.

Over several decades many ranking techniques have been proposed as aids to journal selection by libraries. We review those closely related to physics and others with novel features. There are three main methods of ranking: citation analysis, use or user judgement, and size or ‘productivity’. Citations offer an ‘unobtrusive’ quantitative measure, but not only is the absolute value of a citation in question, but also there is no consensus on a ‘correct’ way to choose the citing journals, nor of the ranking parameter. Citations can, however, point out anomalies and show the changing status of journals over the years. Use and user judgement also employ several alternative methods. These are in the main of limited applicability outside the specific user group in question. There is greater ‘parochialism’ in ‘use’ ranking than in ‘judged value’ lists, with citation lists the most international. In some cases, the attempted ‘quantification’ of subjective judgement will be misleading. Size and productivity rankings are normally concerned with one or other formulation of the Bradford distribution. Since the distribution is not universally valid, for library use the librarian must satisfy him/herself that the collection conforms to the distribution, or that his users would be well served by one that did. This may require considerable effort, and statistics gained will then render the Bradford distribution redundant.

This study develops an integrated zero waste discharge planning approach for improving resource efficiency in a pulp-and-paper manufacturing firm.

The objectives of this study are to (1) identify the environmental, technical and social metrics in resource efficiency; (2) utilize fuzzy multi-objective programming and the hybrid particle swarm optimization algorithm to solve the fuzzy problem; and (3) develop an assessment for resource efficiency improvement in an industrial case study.

The findings demonstrate the superiority of hybrid particle swarm optimization algorithm in generating optimal results for a pulp-and-paper manufacturing firm.

The findings demonstrate the superiority of hybrid particle swarm optimization algorithm in generating optimal results for a pulp-and-paper manufacturing firm.

Resource efficiency is a multi-objective problem in an uncertain environment. In particular, zero waste discharge planning involves minimizing the total cost and maximizing the waste material recovery rate, wastewater reuse, and waste heat recovery.

In a high‐mix middle‐volume production environment for printed circuit board (PCB) assembly, the production efficiency strongly depends not only on the tactical level of how to group PCBs but also on the operational level of how to assign feeders and determine placement sequences in the group setup strategy. The present study discusses the problem of clustering PCBs into groups in such a way that total placement and setup time can be minimized. This problem is motivated by a situation that the reduction of group setup‐time and efficiency loss of placement time should be balanced in a PCB group setup optimization. This research incorporates placement time into the PCB job grouping and presents a weighting similarity measure. To solve component‐feeder assignment and placement sequences for a family of PCBs, an efficient procedure based upon an ant colony optimization (ACO) algorithm is developed. Group setup performance is evaluated and compared under a variety of grouping algorithms. Experiments are conducted to discover situations where the consideration of efficiency loss of placement time can make a significant improvement in PCB group assembly.

The purpose of this paper is to investigate contagion across eight major exchange rates by providing more information on the role of information spillovers.

The empirical analysis makes use of two methodologies that capture channels of contagion. Such methodologies explicitly consider information spillovers characterized by the response of currency markets to real-time macroeconomic surprises, i.e., divergences between expectations and realizations.

The empirical findings denote the presence of contagion effects, originating from information spillovers.

The empirical findings provide insight about how to derive appropriate policy responses, which are crucial for policymakers to understand the source and nature of such exposures, while this insight might have some bearing with respect to the choice of an exchange-rate regime. The results from this paper may also have implications for investors in relevance to portfolio re-balancing and the construction of optimal portfolio diversification strategies.

This is the first empirical attempt that explores the role of informational spillovers in exchange rate markets and also explores the employment of advanced econometric methodologies to satisfy the above research goal.