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The leakage problem caused by machining error, assembly error, wearing and thermal deformation has been the main factor hindering the development of scroll compressor. This paper aims to investigate the lubrication characteristics of radial clearance and further optimize the radial clearance, which can reduce the leakage in the tangential direction of the working chamber.

This paper establishes a model of radial clearance oil film lubrication in scroll compressor. And, the method to solve the Reynolds and energy equations is presented, as well as the dimensionless and discretization by finite element difference method. To verify the established model, performance experiment of scroll compressor for electric vehicle air conditioning system is also carried out.

Based on the presented model, the temperature field and distribution of the oil film in the radial clearance are analyzed. And the influence of the structural parameter on the radial clearance is further discussed. The optimum radial clearance could be achieved at β = 40°–42°, where the orbiting scroll is in the state of rotary balance. And, the simulation results coincide well with the experimental results.

This work provides an effective model to evaluate the lubrication characteristics of radial clearance in scroll compressor, which can provide guidance for the design of scroll compressor.

An efficient supply chain is becoming increasingly important as globalization and technological advancement combine to make the modern marketplace more competitive than ever. An example of this can be seen at Matsushita, a Japanese‐based industry leader who has had to fight to remain competitive in the face of low‐cost Chinese competitors. Faced with declining sales and profits due to cost deficiencies in its supply chain, Matsushita realized that its long‐term success was contingent upon a supply chain realignment. This realignment has included the transfer of many tasks to China. Historically known for its inexpensive land and labor, China is increasingly becoming recognized for its technological expertise and the availability of low‐cost production components. Matsushita’s revamped supply chain is utilizing all of these resources. Through this realignment Matsushita hopes to reverse its recent trend of declining sales and profits; the early results are promising.

This paper aims to investigate microstructure, corrosion behavior and mechanical properties of Mg-4Li and Mg-4Li-3Al.

The microstructure was characterized by using scanning electron microscopy and electron backscatter diffraction. The corrosion behaviors were measured by hydrogen evolution and potentiodynamic polarization tests. The mechanical properties were evaluated by tensile tests.

The addition of Al results in the precipitation of some Mg-Al phase and Al3Li phase particles, and the formation of some fine recrystallized grains.

Mg-4Li-3Al showed a higher corrosion rate than that of Mg-4Li, attributed to the precipitate particles in Mg-4Li-3Al causing microgalvanic corrosion and the change of grain orientation. The addition of 3 Wt. per cent Al increased the tensile strength by solid solution strengthening, precipitation strengthening, refinement strengthening and texture strengthening, whilst the elongation decreased by almost half.

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.

This research aims to empirically investigate the effect of outsourcing on firm level performance metrics, providing evidence about outsourcing influences on a firm's cost‐efficiency, productivity and profitability.

This study is concerned with empirically examining the impact of outsourcing on a firm's performance. The results are based on a sample of 51 publicly traded firms that outsourced parts of their operations between 1990 and 2002. Publicly available accounting data are used to test for changes in operating performances that result from outsourcing decisions. Operating performances are examined over a four‐quarter period after the outsourcing announcement.

This research provides evidence that outsourcing can improve a firm's cost‐efficiency. While existing literature on outsourcing has also sought to draw anecdotal and conceptual evidence that highly visible companies have improved their productivity and profitability as well through outsourcing, the research reveals no evidence that outsourcing will improve a firm's productivity and profitability.

This research is limited to what is available in public databases. Also, financial data pertain to the firm as a whole and not just to the outsourcing department or division, which would obscure the real outsourcing effects on the particular department or division.

This research makes two contributions to both practice and theory. First, this is the first empirical study to examine the link between outsourcing implementation and firm‐level performance metrics. Second, empirical evidence is provided of the difference between outsourcing firms' performance and their non‐outsourcing competitors'. Outsourcing firms have an obvious significant advantage in cost efficiency over their counterparts which do not outsource any activities at the same time. They also may obtain more available resources from outsourcing to invest in other productive capacities.

This research on outsourcing effects is the first to empirically test the relation between the outsourcing decision and the firm's productivity and profitability. Never before has outsourcing played such an important role in business, yet the overall impact of outsourcing on performance remains largely an unexplained puzzle. The research explores opportunities for further research to investigate the returns on outsourcing.

Pursuing objectives despite limited internal resources and leveraging external resources despite non‐ownership are familiar hallmarks of entrepreneurial firms. Although outsourcing is the standard way for businesses to surmount these barriers, entrepreneurial firms often lack the resources to purchase outsourcing arrangements. The purpose of this paper is to shed light on how entrepreneurial firms can better procure and benefit from outsourcing arrangements.

The paper examines six entrepreneurial firms in a Shanghai business incubator as they undertook a variety of outsourcing arrangements. It utilizes an integrative framework based on transaction cost theory, resource dependency theory, and the resource‐based view. It then cross‐hatches those three theory bases with four outsourcing modes (full, partial, spinout, inter‐outsourcing) and case study methodology.

The paper's findings yield three novel propositions for strategic and ex ante entrepreneurial firm outsourcing activities. The propositions pertain to the exchange of non‐traditional resources, vendor‐buyer power differentials, and linkages between internal operations and external resources.

Entrepreneurial firms stand to benefit in particularly vital ways from outsourcing arrangements. Yet, they are often severely constrained with respect to resources. Such strong need combined with limited means is a peculiarly valuable setting but only a paucity of research exists. The original study targets this important setting.

Foreign firms face many supply chain‐related difficulties in China. These include China’s overburdened, underdeveloped physical infrastructure; inexpert, underfunded state‐owned distribution companies; an enormous, fragmented distribution and logistics sector; and regional protectionism. Additionally, foreign firms face bureaucratic restrictions that prohibit them from legally importing, selling, and servicing products in a straightforward manner. Companies are looking to strengthen their supply chains in China in an effort to leverage the country’s cheap labor costs. This strengthening of the supply chain can be accomplished through three methods: the cluster approach; the use of non‐Chinese 3PLs; and the use of local carriers.

Outsourcing emerged as a popular operational strategy in the 1990s and most of current literature was established in the same time. However, the result of outsourcing is still vague. The purpose of this article is to point out gaps in the current literature and examine the link between outsourcing implementation and firms' performance metrics by analysing hard data.

In this research, current outsourcing research (from 1990 to 2003) methodologies are grouped by five categories: case study, survey, conceptual framework, mathematical modeling, and financial data analyses; research scope is identified by three areas: outsourcing determinant, outsourcing process, and outsourcing result.

This article figures out three main gaps in the current literature: lack of objective metrics for outsourcing results evaluation, lack of research on the relationship between outsourcing implementation and firms' value, and lack of research on the outsourcing contract itself.

If research is reported on in the paper this section must be completed and should include suggestions for future research and any identified limitations in the research process.

Based on the literature review, the author provides the roadmap of future research on outsourcing results. To our best knowledge, this is the first comprehensive literature review which informs the major gaps and future research opportunities in outsourcing study.

Thus far, no study collects evidence from practitioners directly to investigate the characteristics of operations management (OM) research that appears to have impacts on OM practice, nor do we know how practitioners evaluate the managerial relevance of OM research. This paper aims to answer two interesting and important questions: how do practitioners judge the managerial relevance of OM research; and whether practitioners' criteria on managerial relevance can help OM researchers improve the relevance?

A panel of senior executives was asked to read the top 10 most downloaded papers from the Journal of Operations Management and fill the designed questionnaire. Following Cronbach's cumulative theory‐building process through which progress is made by successively testing the efficacy of the measures, this research examined the diverse disciplines, consolidated relevant findings, and integrated them into a tractable, meaningful research framework.

This paper reveals that practitioners evaluate our OM research by three criteria: whether academic research is applicable or implementable (solution oriented), whether academic research provides novel insights or new perspectives to management (eye opening), and whether academic research helps practitioners recognize their situations (accessibility).

While the awareness of managerial relevance in OM research has been growing, few systematic, quantitative‐oriented empirical studies of practitioners' attitude toward academic OM research exist in current literature. This paper directly explores practitioners' opinions on managerial relevance through quantitative analysis and identified several possible dimensions to pursue managerial relevance in OM research.

Prior to the economic reform movement, China’s centrally planned, three‐tier system dominated the distribution sector. After the 1980s, this system gradually shifted away from the socialist mode to the free market mode. Today, China’s distribution system lies somewhere between these two modes. Since the reform, China’s government has been encouraging export‐oriented foreign firms’ investments in free trade zones along the coast. Foreign firms do not enjoy the same inland distribution and logistics rights as their Chinese counterparts. However, the distribution puzzle is not only faced by foreign firms, but also by Chinese firms that operate nationwide. China’s undeveloped infrastructure, government regulations, and regional protectionism fragment distribution channels throughout China. However, there are three main forces that are changing and modernizing China’s distribution and logistics system. These are the booming economy, entering the WTO and e‐commerce. The inevitable revolution of China’s distribution and logistics system is on the way.