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The purpose of this paper is to propose a quasi-three-dimensional (3D) thermohydrodynamic (THD) model for oil film bearings with non-Newtonian and temperature-viscosity effects. Its performance factors, including precision and time consumption, are investigated.

Two-dimensional (2D), 3D and quasi-3D numerical models are built. The thermal and mechanical behaviors of two types of oil film bearings are simulated. All the results are compared with solutions of commercial ANSYS CFX.

The 2D THD model fails to predict the temperature and pressure field. The results of the quasi-3D THD model coincide well with those of the 3D THD model and CFX at any condition. Compared with the 3D THD model, the quasi-3D THD model can greatly reduce the CPU time consumption, especially at a high rotational speed.

This quasi-3D THD model is proposed in this paper for the first time. Transient mechanical and thermal analyses of high-speed rotor-bearing system are widely conducted using the traditional 3D THD model; however, the process is very time-consuming. The quasi-3D THD model can be an excellent alternative with high precision and fast simulation speed.

The electromagnetic fields have a great influence on the behaviour of all the living systems. The as low as reasonably achievable (ALARA) principle imposes, in case of long exposures to low (i.e. power systems) or high frequency (i.e. microwave systems or cell phones) fields, some limitations to the radiated fields by the industrial equipment. On the other hand, some benefits can be taken from the effects of the electromagnetic fields on the living being: the hyperthermal technique is well known for the treatment of the cancer. Either we want to be protected from the fields, or we want to take benefit of the positive effects of these fields, all the effects thermal as well as genetic have to be well known. Like in any industrial application, the electromagnetic field computation allows a better knowledge of the phenomena, and an optimised design. Hence, there is a very important challenge for the techniques of computation of electromagnetic fields. The major difficulties that appear are: (1) related to the material properties – the “material” (the human body) has very unusual properties (magnetic permeability, electric permittivity, electric conductivity), these properties are not well known and depend on the activity of the person, and this material is an active material at the cell scale; (2) related to the coupling phenomena – the problem is actually a coupled problem: the thermal effect is one of the major effects and it is affected by the blood circulation; (3) related to the geometry – the geometry is complex and one has to take into account the environment. The problems that we have to face with are – the identification of the properties of the “material”, the coupled problem solution and the representation of the simulated phenomena.

The purpose of this paper is to improve the corrosion resistance of anodized 6063 Al alloy inertial air–water separator by means of silane technology and to investigate the effect of corrosion-generated surface roughness changes on aerodynamic performance.

The BTSE-KH560 double-layer silane film treatment technique is used to close micropores on the anodic oxide film surface. The microstructure of the coating is observed by scanning electron microscopy, the coating structure of the specimens is determined by X-ray diffraction (XPS) and the corrosion resistance is determined by electrochemical and salt-spray tests. Computational fluid dynamics is also used to calculate the effect of roughness and analyse the change in separator performance.

The silane film deposited on the surface of the anodic oxide film acts as a good seal against microporous defects on the surface of the anodic oxide film and reduces the surface roughness. Electrochemical and salt-spray tests show that the silane film improved the corrosion resistance of the anodized film. The roughness produced by the corrosion deteriorates the performance of the separator.

The porous structure of the anodized coating makes it easier for corrosive ions to enter the substrate and cause pitting corrosion. Therefore, in this study, the corrosion behaviour of the coating in the marine environment and its effect on aerodynamic performance are investigated using a BTSE-KH560 double-layer silane coating with a sealing effect.

In the last 10 years there has been an increasing trend towards miniaturisation in mass spectrometry. Miniature versions of magnetic sector, time of flight (TOF) and quadrupole mass spectrometers (QMS) have all been developed. Some of these systems use silicon microengineering technology, e.g. MEMS, to achieve the small geometries necessary, other systems use conventional engineering but on a reduced scale. The scientific advantages of miniaturisation include the ability to measure and monitor at higher vacuum pressures than hitherto (>10⁻² mbar). Miniaturisation also offers advantages due to the reduced cost and resulting portable nature of the smaller instruments.

This paper aims to empirically explore the influence that different factors have on the creation of university spin-offs.

This is an exploratory study that uses a multilevel design. The study follows a purposive sampling method where data are gathered from a variety of sources. The hypotheses are tested with a sample of 52 universities from the Latin American region using multiple hierarchical regression analysis.

The results indicate that entrepreneurial orientation, incubators or entrepreneurship support programs and goods market efficiency are the factors that positively influence the creation of university spin-offs.

The results of this study should be observed in light of some limitations. The sample size is an important factor, as a bigger sample could allow for examination of cross-institutional variation in the context of different countries. In addition, the lack of records or public databases makes it difficult to incorporate more information on spin-offs creation, including features or firm performance.

This study is the first to empirically explore the university spin-offs creation phenomenon in the Latin American region. Hence, it contributes to university entrepreneurship literature, specifically to better understand this phenomenon from a more holistic perspective across different levels of analysis at the same time that it incorporates previous proposals to explain entrepreneurial orientation at universities.

Advances in rapid prototyping and machining have resulted in reduced lead times for injection moulding tooling. Comparisons between aluminium and stereolithography (SL) tools are made with regard to the ejection forces required to push mouldings from the tools, heat transfer through the tools and the surface roughness of the tools. The results show that ejection forces for both types of tools are increased when a longer cooling time prior to ejection is used. The ejection forces required from a rough aluminium tool are considerably higher than those from a smooth aluminium tool. SL tools do not appear to be subjected to any smoothing as a result of moulding polypropylene parts. The rubber like nature of the tool’s surface is as a direct consequence of the low glass transition temperature and low thermal conductivity of the tool material. Further potential benefits of the low thermal properties of the tool are discussed.

The goal of this research is to examine the link between employees' beliefs that organizational decision-making processes are guided by self-serving behaviors and their own turnover intentions, as well as how this link may be buffered by four distinct resources, two that speak to the nature of peer exchanges (knowledge sharing and relationship informality) and two that capture critical aspects of the organizational environment (change climate and forgiveness climate).

Quantitative survey data were collected among 208 employees who work in the oil and gas sector in Mozambique.

The results indicate that employees' beliefs about dysfunctional political games stimulate their plans to quit. Yet this translation is less likely to occur to the extent that their peer relationships are marked by frequent and informal exchanges and that organizational leaders embrace change and forgiveness.

For organizations, these findings offer pertinent insights into different circumstances in which decision-related frustrations are less likely to escalate into quitting plans. In particular, such escalation can be avoided to the extent that employees feel supported by the frequency and informal nature of their communication with colleagues, as well as the extent to which organizational leaders encourage change and practice forgiveness.

This study adds to extant research by explicating four unexplored buffers that diminish the risk that frustrations with politicized decision-making translate into enhanced turnover intentions.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

Numerous studies have concluded that immigration has very small effects on wages or unemployment, even when the immigration flow is very large. Three reasons suggested for this are that immigration: (1) is not supply-push, but may instead be driven by demand-pull factors; (2) is likely to cause some out-migration; and (3) may induce flows of other factors across the economy. Surprisingly, few studies consider another obvious explanation: immigrant workers also consume locally, which means immigration stimulates the local demand for labor. Previous researchers have generally ignored the measurement of immigration's effects on labor demand, perhaps because when immigration, out-migration, and immigrant consumption occur simultaneously in the same labor market, it is very difficult to isolate immigration's effect on labor demand. This paper measures the labor demand-augmenting effects of immigration using a two-sector model of a very special case in which the receiving economy consists of: (a) an export industry employing both immigrants and natives; and (b) a retail industry employing native labor that is driven by local demand. The model can incorporate both supply-push and demand-pull immigration as well as out-migration. The model's important implication is that since immigration is exogenous to the retail sector, an unbiased estimate of the demand effect of immigration can be obtained without having to use instrumental variables estimation or other statistical procedures that may introduce new sources of bias. Fortunately, the economy in our model matches a very convenient test case: Dawson County, Nebraska. Dawson County recently experienced a surge in demand-pull immigration due to the location of a large export-driven meatpacking plant. This exogenous capital shock pulled in many Hispanic immigrant workers, who did not immediately seek work in the retail sector because of social and language barriers. This immigration led to higher retail wages and housing prices, confirming that immigration is capable of exerting significant effects on local labor demand.

Longevity risk, that is, the uncertainty of the demographic survival rate, is an important risk for insurance companies and pension funds, which have large, and long‐term, exposures to survivorship. The purpose of this paper is to propose a new model to describe this demographic survival risk.

The model proposed in this paper satisfies all the desired properties of a survival rate and has an explicit distribution for both single years and accumulative years.

The results show that it is important to consider the expected shift and risk premium of life table uncertainty and the stochastic behaviour of survival rates when pricing the survivor derivatives.

This model can be applied to the rapidly growing market for survivor derivatives.