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In order to prevent the brittle fracture accident, minimum design metal temperature of ferrite steel should be limited. After the minimum design metal temperature curve in American Society of Mechanical Engineers VIII-2 (2007) was proposed, much related research has been done in recent years. In this paper, firstly the theoretical basis of four methods used to determine the minimum design metal temperature was introduced. Secondly, the mechanical properties of Q345R was measured by tensile test, Charpy v-notch impact test and fracture toughness test Thirdly, minimum design metal temperature curve of Q345R that determined by four methods were obtained. There are obvious difference between the curves of Q345R that determined by four methods. It can be concluded that low temperature fracture toughness of Q345R is underestimated when classifying Q345R into exemption curve A in American Society of Mechanical Engineers VIII-2 (2007). [ABSTRACT FROM AUTHOR]

Sealing performance of standard rubber gaskets in the radial contact seal structure are observed through the experiment. A kind of profiled rubber gasket is proposed to replace the standard gasket. Leakage experiment and numerical simulation are carried out to study the sealing performance and failure mode of the profiled gasket. Several equations are presented to help analyze the failure reason. Results show that sealing performance of the profiled rubber gasket is more reliable than that of the standard rubber gasket. The failure reason of the profiled rubber gasket is that the friction force between the gasket external face and tube wall cannot balance the tube internal pressure. Dimension precision of the metal compressive ring has a great effect on the failure pressure. [ABSTRACT FROM AUTHOR]

Bursting disc overpressure relief device services as the last safety barrier in preventing catastrophic overpressure of the pressure vessel. The design of ultra-high pressure bursting disc device is a tough engineering issue as it requires both strength and sealing reliability under ultra-high working pressure. In this paper, a novel ultra-high pressure bursting disc device is proposed as well as the sealing structure is designed. Firstly, the novel bursting disc device structure is introduced. Then, the wall thickness of the sealing ring is designed based on elastoplastic mechanical analysis. Numerical simulation is also conducted to investigate the mechanical and sealing performance theoretically. At last, the strength and the reliability of the sealing performance is proved by hydraulic burst test. [ABSTRACT FROM AUTHOR]

Endovascular thrombectomy revolutionized the treatment of acute ischemic stroke. Nevertheless, access to endovascular thrombectomy is limited in many parts of the world. Asia holds 60% of the world's population and its countries carry some of the highest stroke disease burden. To understand the availability of endovascular thrombectomy and intravenous thrombolysis in this region, we interviewed stroke neurologists and neuro-interventionists of 19 Asian countries, and found a large disparity in access to endovascular thrombectomy and intravenous thrombolysis between high- and low-income countries. Lack of neuro-interventionists, comprehensive stroke units, stroke triage systems and high treatment cost are the major obstacles to wider accessibility of endovascular thrombectomy, especially among developing countries. The potential solutions to provide equitable access to stroke revascularization therapy are discussed. [ABSTRACT FROM AUTHOR]

This study investigates a retailer's incentive for sharing private demand information with a supplier who may encroach the retail channel by imposing a fixed entry cost. Although conventional wisdom suggests that a retailer should withhold her private demand observations to maintain an information advantage over the supplier, we obtain a different conclusion by demonstrating that the retailer may prefer to voluntarily share the demand information in anticipation of supplier encroachment. The intuition is that in face of the threat of supplier encroachment, sharing low demand information may prevent the supplier from establishing a direct selling channel, which will reduce downstream channel competition. This strategic effect of information sharing is new and only becomes dominant when there is an intermediate entry cost for encroachment and a high channel substitution rate. In contrast, when there are deviations from these conditions, the supplier's equilibrium encroachment decision is consistent and irrespective of the retailer's decision to share information, which makes withholding the demand information more beneficial to the retailer. The change of information sharing structure in the channel also leads to some unintended payoff implications, as the supplier's and channel's payoffs exhibit non‐monotonic relations to the entry cost or channel substitution rate. [ABSTRACT FROM AUTHOR]

The aim of this article is to develop an accurate three-dimensional finite element model of deep groove ball bearing to analyze fatigue lives for outer race and inner race. By the finite element analysis, the stress and strain datasets for outer race and inner race are obtained and used to calculate the fatigue lives. Based on a reliable fatigue criterion, the effect of various applied loads on the fatigue lives of outer race and inner race is investigated. Several parameters, namely the raceway groove curvature radii of outer race and inner race and the thicknesses of outer race and inner race are varied to investigate their effect on the fatigue lives. Research results provide useful guidelines for determining the design parameters. [ABSTRACT FROM PUBLISHER]

Health messages have limited effects on young smokers. The health effects typically have long latent periods, and the appreciation of risk depends on the meaning given to longevity. This study aims to understand how college student smokers interpreted the risks of losing 10 years of life because of smoking. In-depth semistructured interviews were conducted with 23 male smokers from a relatively low-achieving college in southern Taiwan. The participants had vague ideas about the future; were not expecting a successful life, thought life was stressful and boring; and expressed that there was no need to live too long. Many believed that removing the stress and having a composed lifestyle was the way to becoming healthy, which could be achieved only by people with economic success. They would quit had they been rich. Empowerment to help young smokers gain control over their life events may be the key to tobacco control. [ABSTRACT FROM PUBLISHER]