Jun Yasuda, Koji Takahashi and Hideki Okada
The purpose of this study is to clarify the influence of stress ratio (R) on the effects of shot peening (SP) on the fatigue limit of high-strength steel containing an artificial…
Abstract
Purpose
The purpose of this study is to clarify the influence of stress ratio (R) on the effects of shot peening (SP) on the fatigue limit of high-strength steel containing an artificial small defect.
Design/methodology/approach
SP was subjected on the specimens with a semi-circular slit with a depth of a=0.1, 0.2 and 0.3 mm. Then, bending fatigue tests were carried out under R=0.4.
Findings
The fatigue limits of specimens with a semi-circular slit were improved by SP under R=0.4. The fatigue limits of the SP specimens with a semi-circular slit under a=0.2 mm fractured outside the slit, and they had considerably high fatigue limits equal to specimens without a slit. Therefore, a semi-circular slit with a depth of under a=0.2 mm could be rendered harmless by SP under R=0.4. Compared to the results of R=0, the increasing ratios of fatigue limits under R=0.4 were lower than those under R=0. However, the size of semi-circular slit that could be rendered harmless by SP was same. In addition, it was found that whether the semi-circular slit is rendered harmless or not is decided by the relationship between the stress intensity factor range of semi-circular cracks and the threshold stress intensity factor regardless of stress ratio.
Practical implications
The proposed method can be applied to mechanical parts used in vehicles, aircraft and trains.
Originality/value
This is the first paper to investigate the fatigue limits after SP in materials containing a surface defect under positive stress ratio. In this study, the authors investigated the influence of stress ratio on the effects of SP on the fatigue limit containing a surface defects.
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S.M. El‐Sawy, F.A. Abdel‐Mohdy and I.M. Morsi
Twenty seven formulations were prepared based on three grades of laboratory prepared silver pigments. These formulations could be classified into three main groups. The aim of…
Abstract
Twenty seven formulations were prepared based on three grades of laboratory prepared silver pigments. These formulations could be classified into three main groups. The aim of this classification is to study the effect of the type of binder and pigment on the efficiency of the formulated electric conductive paints. A commercial silver conductive paint is used for comparison. The formulated paints were laboratory tested for adhesion, hardness, acid and alkali resistance, corrosion protection and electric conductivity. It has been found that these formulations pass all the laboratory tests. The conductivity of the formulated paints is higher than the conductivity of the commercial one. Both of the pigment particle size and the type of the used binder effect the conductivity of the formulated paints.
MORTON N. LANE and OLEG Y. MOVCHAN
Risk is difficult to measure — so difficult that no single measure seems robust enough for all circumstances. This is especially true of measuring the risk contained in…
Abstract
Risk is difficult to measure — so difficult that no single measure seems robust enough for all circumstances. This is especially true of measuring the risk contained in insurance‐linked securities. Insurance risk is usually asymmetrically skewed. As a conse‐quence, traditional capital market risk measures — expected loss, probability of default, and the standard deviation of return out‐comes — are less than perfect to the insurance task. Without a good risk measure, it is impossible to compare the risk‐adjusted pricing of insurance‐linked notes on a consistent basis. It is impossible to tell which securities are cheap and which are expensive. It is impossible to decide on their value relative to more traditional investments.
Jun Fu, Jianxing Li, Wei Chen, Zengfeng Zhang, Hong Mao and Yuan Tang
The purpose of this paper is to present experimental studies on the designed muffler which contains ceramic foam and has the integration function of purification and noise…
Abstract
Purpose
The purpose of this paper is to present experimental studies on the designed muffler which contains ceramic foam and has the integration function of purification and noise elimination.
Design/methodology/approach
Comparative tests were done on a diesel engine with no muffler, the original muffler and the purification muffler. The soot index (light absorption coefficient), A-weighted sound pressure level and fuel consumption rate, which were collected by the partial flow opacity method, the insertion loss measurement of spatial five points and the load characteristics tests, respectively, and the effects of purification and noise elimination were studied.
Findings
The results of this paper state that the purification muffler shows great improvement on exhaust soot purification and noise elimination. The variation in diesel fuel consumption rate was small, the sound pressure level of purification muffler was reduced by 6 to 10 dB, the insertion loss of the purification muffler was increased by 6.41 dB and the average light absorption coefficient decreased by 57.8 percent compared with the original muffler.
Originality/value
The value of this study is that it supplies a purification muffler which contains a ceramic foam. Under the prerequisite of little effect on the fuel economy of diesel engine, the purification muffler shows great improvement in exhaust soot purification and noise elimination.
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S.M. El‐Sawy, I.M. Morsi and F.A. Abdel‐Mohdy
Three different methods have been studied to prepare silver powder pigments in order to find out the most suitable product for application in conductive paints. X‐ray analysis…
Abstract
Three different methods have been studied to prepare silver powder pigments in order to find out the most suitable product for application in conductive paints. X‐ray analysis, specific gravity, pH value, water solubility, oil absorption, particle size distribution, and particle shape of the prepared silver powders were measured and compared with a commercial pigment. It was found that two of the three grades of silver powders have more suitable properties for application as conductive pigments.
Jun Jin, Max von Zedtwitz and Li Choy Chong
The purpose of this paper is to investigate how international R & D alliances are formed during industry transition from the point of view of the local Chinese partner…
Abstract
Purpose
The purpose of this paper is to investigate how international R & D alliances are formed during industry transition from the point of view of the local Chinese partner.
Design/methodology/approach
Review of industry data provided by Chinese Statistical Office coupled with four in-depth case studies.
Findings
The nature of the technology, the characteristics of partners and the previous cooperation experience between partners are significantly related to the R & D alliance formation. The research also suggests that during this fast-growing transition period, Chinese local firms preferred non-equity contractual agreements over equity joint venture such as R & D alliance modes, and Chinese local firms favoured American and European multinational corporations (MNCs) as their alliance partners over MNCs from other countries, including the highly developed Japan and Korea.
Research limitations/implications
Single-industry focus (telecommunications), and anonymization of cases because of confidentiality of case firms. Single-country focus (China).
Practical implications
Firms in China and other emerging countries can improve their technological capability (TC) by choice to facilitate future alliance formation to access and learn the latest technology from their alliance partners, especially during the transition period of an industry and when mature and emerging technologies co-exist.
Originality/value
This paper refines alliance theory by focusing on an industry in transition and analyses formation decision factors from the point of view of the smaller domestic partner – usually studies do not differentiate as to industry maturity and inequality between partners.
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Bawo Onesirosan James, Joyce Ohiole Omoaregba and Esther Osemudiamen Okogbenin
Stigmatising attitudes towards persons with mental illness are commonly reported among health professionals. Familiarity with mental illness has been reported to improve these…
Abstract
Stigmatising attitudes towards persons with mental illness are commonly reported among health professionals. Familiarity with mental illness has been reported to improve these attitudes. Very few studies have compared future medical doctors' attitudes toward types of mental illness, substance use disorders and physical illness. A cross-sectional survey of 5th and 6th year medical students as well as recently graduated medical doctors was conducted in April 2011. The 12-item level of contact report and the Attitude towards Mental Illness Questionnaire were administered. Partici -pants endorsed stigmatising attitudes towards mental illness; with attitudes more adverse for schizophrenia compared to depression. Stigmatising attitudes were similarly endorsed for substance use disorders. Paradoxically, attitudes towards HIV/AIDS were positive and similar to diabetes mellitus. Increasing familiarity with mental illness was weakly associated with better attitudes towards depression and schizophrenia. Stigmatising attitudes towards depression and schizophrenia are common among future doctors. Efforts to combat stigma are urgently needed and should be promoted among medical students and recent medical graduates.
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Yunuen Ysela Mandujano-Salazar
Japan is characterized by its businesses older than 100 years, commonly known as shinise (老舗) – long-standing companies – which tend to be family businesses. Longevity in Japanese…
Abstract
Japan is characterized by its businesses older than 100 years, commonly known as shinise (老舗) – long-standing companies – which tend to be family businesses. Longevity in Japanese family businesses has been attributed, among other factors, to the system of the ie, or patrilineal household line. This chapter follows a sociocultural perspective and uses documental and media textual analysis to identify the cultural and structural attributes and the strategies that shinise have implemented when facing new and intimidating economic, political, and social circumstances under extreme contexts such as wars, structural changes, and national catastrophes and crises while protecting the family structure behind the firm. It is found that, for these firms, the ie comes first than individuals, and so does talent over lineage. The relevance of someone who shares the values that resonate with those of the business is imperative, but also that the leader has a resilient character and an innovative and proactive mind, and understands that his/her major purpose should be protecting the firm and securing its continuity.
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Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way…
Abstract
Investigates the differences in protocols between arbitral tribunals and courts, with particular emphasis on US, Greek and English law. Gives examples of each country and its way of using the law in specific circumstances, and shows the variations therein. Sums up that arbitration is much the better way to gok as it avoids delays and expenses, plus the vexation/frustration of normal litigation. Concludes that the US and Greek constitutions and common law tradition in England appear to allow involved parties to choose their own judge, who can thus be an arbitrator. Discusses e‐commerce and speculates on this for the future.
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Jun Liu, Zhinan Zhang, Zhe Ji and Youbai Xie
This paper aims to investigate the effects of reciprocating frequency, large normal load on friction and wear behavior of hydrogenated diamond-like carbon (H-DLC) coating against…
Abstract
Purpose
This paper aims to investigate the effects of reciprocating frequency, large normal load on friction and wear behavior of hydrogenated diamond-like carbon (H-DLC) coating against Ti-6Al-4V ball under dry and lubricated conditions.
Design/methodology/approach
The friction and wear mechanisms are analyzed by scanning electron microscope, energy dispersive spectroscopy and Raman spectroscopy.
Findings
The results show that as reciprocating frequency increases under lubricated conditions, the friction coefficient decreases first and then increases. When the reciprocating frequency is 2.54 Hz, the value of friction coefficient reaches the minimum. The friction reduction is because of the transformation from sp3 to sp2, the formation of transfer layer on Ti-6Al-4V ball and the reduction in viscous friction, whereas the increase of friction coefficient is related to wear. In dry conditions, the friction coefficient is between 0.06 and 0.1. And, the service life of H-DLC coating decreases with the increase in reciprocating frequency and normal load.
Research limitations/implications
It is confirmed that adding the lubricant could prolong the service life of H-DLC coating and reduce friction and wear efficiently. And, the wear mechanisms under dry and lubricated conditions encompass abrasive wear and adhesive wear.
Originality/value
The results are helpful for application of diamond-like carbon coating.