Search results

1 – 10 of 369
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 6 November 2017

Hyung Goun Joo, Kang Yong Lee, Guo Ming Luo and Da Quan Zhang

The purpose of this paper is to investigate the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

123

Abstract

Purpose

The purpose of this paper is to investigate the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

Design/methodology/approach

Al2O3 particles and 10 wt% NaCl solution are used to evaluate erosion and corrosion resistance of WC-Ni vacuum brazed coating. Combined test of erosion and corrosion is also conducted. The microstructure of each specimen is characterized by the scanning electron microscopy. The chemical composition was determined by energy-dispersive X-ray spectroscopy.

Findings

WC-Ni vacuum brazed coating layer is effective protective coating under combined erosion and corrosion environment. The weight loss of coating layer is more reduced as the cumulative test time.

Originality/value

WC-Ni vacuum brazed coatings are investigated to check characteristic of the combined erosion and corrosion environment. WC-Ni vacuum brazed coatings are kind of diffusion coating that attract attention because of the resistance of superb impact and corrosion in comparison with other coatings. Some previous researches reported the properties of vacuum brazed WC material. Erosion and corrosion behaviors of WC-Ni vacuum brazed coatings were studied in our previous research, respectively. Hence, in this research, the principal objective is to examine the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Access Restricted. View access options
Article
Publication date: 1 March 2005

Geun Woo Kim and Kang Yong Lee

Optimisation of the package design in order to reduce stresses in a plastic small outline J‐lead (SOJ) package and to thereby prevent fractures during the infrared soldering…

529

Abstract

Purpose

Optimisation of the package design in order to reduce stresses in a plastic small outline J‐lead (SOJ) package and to thereby prevent fractures during the infrared soldering process.

Design/methodology/approach

Finite element (FE) modelling was used, both with and without crack tip‐modelling. A design of experiment (DOE) approach was used to reduce the number of FE models required.

Findings

The optimum design values for minimization of thermal stress and the prevention of fracture were found to be different. The results allow the values of design variables such as the dimensions and material properties of the IC package.

Practical implications

To reduce the stresses and thereby prevent fracture, the values of the Young's modulus and coefficient of thermal expansion of the epoxy moulding compound should be reduced.

Originality/value

The work has used both stress analysis and fracture mechanics analysis along with DOE to identify the design values which simultaneously reduce the thermal stresses and prevent the fracture of the IC package.

Details

Soldering & Surface Mount Technology, vol. 17 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

Access Restricted. View access options
Article
Publication date: 1 September 2005

Ji Hyuck Yang and Kang Yong Lee

To apply the design of experiments (DOE) methodology to the problem of cracking of plastic ball grid array (PBGA) packages during the reflow soldering process.

825

Abstract

Purpose

To apply the design of experiments (DOE) methodology to the problem of cracking of plastic ball grid array (PBGA) packages during the reflow soldering process.

Design/methodology/approach

The DOE methodology was used in order to identify the optimum design. CAE was used for the required stress analysis and for integral calculation during crack analysis.

Findings

The optimum design to reduce the stress and fracture probability for the PBGA package was obtained and the DOE technique was shown to be very powerful for establishing the optimum design when there are many design parameters.

Research limitations/implications

In future research, a robust design methodology could be applied including design for six sigma considering the noise parameters.

Practical implications

For better design of a PBGA package, the DOE methodology has been shown to be very useful.

Originality/value

In this paper, application of the DOE approach to a PBGA package design in order to reduce the stresses and probability of fracture was attempted for the first time.

Details

Soldering & Surface Mount Technology, vol. 17 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

Access Restricted. View access options
Article
Publication date: 15 August 2008

T.S.N. Sankara Narayanan, Young Woo Park and Kang Yong Lee

The objective of this paper is to study the effect of a commercial lubricant, which contains a 50‐50 mixture of zinc diamyldithiocarbamate and petroleum oil, on the fretting…

455

Abstract

Purpose

The objective of this paper is to study the effect of a commercial lubricant, which contains a 50‐50 mixture of zinc diamyldithiocarbamate and petroleum oil, on the fretting corrosion of tin‐plated copper alloy contacts.

Design/methodology/approach

The change in contact resistance as a function of fretting cycles was used to assess the effectiveness of the lubricant in preventing the fretting corrosion of tin‐plated contacts. The surface profile, surface roughness, extent of fretting damage and extent of oxidation of the contact zone were assessed by a laser scanning microscope and surface analytical techniques to correlate the change in contact resistance with fretting cycles.

Findings

The lubricant film provides a surface coverage of 6.76±1 mg/cm2 and it easily establishes metallic asperity contact between the mated tin‐plated contacts. The contact resistance of lubricated contacts remains stable for several thousand fretting cycles. Lubricated contacts reach a threshold value of 0.1 Ω around 100,000 cycles, whereas unlubricated contact reaches this value around 13,500 cycles itself. For lubricated contacts, the extent of mechanical wear of the tin coating is significantly reduced. As a result, they experience a lesser damage at the contact zone and exhibit a smoother profile. The formation of tin oxide is not appreciable and there is no oxide accumulation at the contact zone even at 380,000 cycles. The lubricant is very effective in delaying the fretting wear during the initial stages and in preventing the oxidation and accumulation of oxidation products at the contact zone in the later stages.

Originality/value

Metallic dialkyldithiocarbamates are useful anti‐wear and extreme pressure additives for lubricating oils. Dithiocarbamates improve the antioxidant properties of the lubricants and are effective in reducing the wear and increasing the friction‐reducing and load‐carrying ability of the base stock. The use of molybdenum dithiocarbamate as a grease additive is found to be effective in reducing fretting corrosion of ball bearings under random rotary vibrating conditions. The effect of dithiocarbamate containing lubricant oils or greases on the fretting corrosion of electrical contacts has not far been studied. The paper explores the effect of a lubricant that contains a 50‐50 mixture of petroleum oil and zinc diamyldithiocarbamate on the fretting corrosion of tin‐plated contact.

Details

Industrial Lubrication and Tribology, vol. 60 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Available. Open Access. Open Access
Article
Publication date: 31 December 2007

Myoung-Kang Heo, Yong Jin Kim and Min-Sung Kim

The studies focusing on inbound logistics in the automobile industry have been limited because of the relatively small portion of logistics cost. But now it is recognized as one…

475

Abstract

The studies focusing on inbound logistics in the automobile industry have been limited because of the relatively small portion of logistics cost. But now it is recognized as one of the critical factors for efficient execution of supply chain management (SCM). The survey of suppliers in the automobile industry conducted in this study indicated significant relationships among logistics performance, logistics outsourcing, and performance evaluation level. This research is three-fold. First, current status of part supplier's logistics was analyzed by interviews with inbound logistics providers and suppliers. Second, management type of logistics was analyzed. There were three kinds of logistics -two kinds of logistics outsourcing and direct control by the supplier. Each type of logistics management showed differences about performance. Third, logistics performance evaluation and its relation with the actual logistics performance were presented. Comparable performance evaluation factors were selected, and it is shown that they had a correlation with actual performance.

Details

Journal of International Logistics and Trade, vol. 5 no. 2
Type: Research Article
ISSN: 1738-2122

Keywords

Access Restricted. View access options
Article
Publication date: 12 March 2019

Hyun Kyung Lee and Hyeok Yong Kwon

The purpose of this paper is to explore whether and how the individual perceptions on income inequality and the inequality of opportunities affect two different modes of political…

858

Abstract

Purpose

The purpose of this paper is to explore whether and how the individual perceptions on income inequality and the inequality of opportunities affect two different modes of political participation, institutional and non-institutional, in South Korea.

Design/methodology/approach

The paper analyzes the Korean General Social Survey 2009 and 2014 and estimates logit and OLS models.

Findings

The authors find that neither the perceived inequality of income distribution nor the perceived inequality of opportunities affects the likelihood of individuals’ vote participation. The authors, however, find that the perceptions of inequality, both in terms of outcomes and opportunities affect citizens’ engagement in non-institutional forms of political participation.

Originality/value

This study provides a new discussion point about the political consequences of inequality in Korea. This paper distinguishes and analyzes the relative importance of perceived inequality of the outcomes and opportunities in democratic engagements. By considering various types of participation, institutional and non-institutional, this study contributes to deepen our understanding of the factors that drive citizens’ democratic political engagements.

Details

Asian Education and Development Studies, vol. 8 no. 3
Type: Research Article
ISSN: 2046-3162

Keywords

Access Restricted. View access options
Article
Publication date: 25 September 2020

Jeanne Ho, Trivina Kang and Imran Shaari

The purpose of this paper is to examine leading from the middle, which is consistent with calls to distribute leadership, while expanding the direction of influence, from the…

488

Abstract

Purpose

The purpose of this paper is to examine leading from the middle, which is consistent with calls to distribute leadership, while expanding the direction of influence, from the normal top-down to include a bottom-up or lateral direction. The paper proposes that the position of the vice-principal enables the role incumbent to lead from the middle as a boundary spanner. The research question was what leadership from the middle looks like for vice-principals.

Design/methodology/approach

The study consisted of interviews of 28 vice-principals and 10 principals. A mixed case and theme-oriented strategy was adapted, with member checking with each vice-principal.

Findings

The findings indicate that in leading from the middle, vice-principals play boundary spanning roles of connecting, translating and brokering: (1) connecting between organisational levels, (2) translating between vision/direction and actualisation, (3) connecting between middle managers and (4) brokering and translating between the ministry and the school.

Originality/value

Leading from the middle is a nascent concept which is worth exploring, given the complexity of educational systems with multiple ecological levels, and the need for leadership to create coherence between the levels.

Details

Journal of Educational Administration, vol. 59 no. 2
Type: Research Article
ISSN: 0957-8234

Keywords

Access Restricted. View access options
Article
Publication date: 8 January 2018

Yong-Sang Woo, Minjung Kang and Ho-Young Lee

Audit firm bankruptcy can have significant negative impacts on the stock prices of client firms. The purpose of this paper is to identify determinants of audit firm bankruptcy…

901

Abstract

Purpose

Audit firm bankruptcy can have significant negative impacts on the stock prices of client firms. The purpose of this paper is to identify determinants of audit firm bankruptcy risk as measured by costs of debt.

Design/methodology/approach

Using audit firm data publicly available in Korea, this study empirically examines whether client portfolio, financial, and organizational characteristics are associated with the weighted average interest rates assumed by auditors.

Findings

The authors find empirical evidence that audit firms’ client portfolio characteristics, including the incidence (or number) of lawsuits against the auditor, the proportion of audit clients under surveillance, the proportion of initial audit engagements, and the proportion of listed companies of audit clients, are positively associated with the cost of debt. The authors also find several financial and organizational characteristics associated with the cost of debt.

Practical implications

The findings of this study suggest that client portfolio characteristics as well as financial and organizational characteristics are important determinants of the cost of debt in audit firms, and that these characteristics are different from those of firms in other industries. Identifying the determinants of audit firms’ cost of debt provides insight to regulators, client firms, and capital market participants.

Originality/value

This study examines the default risk of audit firms that play an important monitoring role in capital markets. By utilizing unique data about audit firms available in Korea, this study is the first study to empirically examine the effect of detailed audit firm characteristics on audit firm’s default risk.

Details

Managerial Finance, vol. 44 no. 1
Type: Research Article
ISSN: 0307-4358

Keywords

Access Restricted. View access options
Article
Publication date: 15 February 2024

Chun Cheng

This study investigates the direct influence of ambidextrous leadership on employees’ innovation behaviour, the mediating role of innovative self-efficacy and harmonious work…

765

Abstract

Purpose

This study investigates the direct influence of ambidextrous leadership on employees’ innovation behaviour, the mediating role of innovative self-efficacy and harmonious work passion, and the moderating role of Zhong-Yong thinking.

Design/methodology/approach

The authors conducted a series of questionnaire surveys to collect data in three time periods and from multiple sources; 332 supervisor–subordinate matched samples were obtained. The hypothesised relationships were tested using structural equation modelling and ProClin.

Findings

Ambidextrous leadership is positively associated with employees’ innovation behaviour, while innovative self-efficacy and harmonious work passion play mediating roles. The analysis further confirms that innovative self-efficacy and harmonious work passion play a chained double-mediating role between ambidextrous leadership and employees’ innovation behaviour, while Zhong-Yong thinking plays moderating roles between ambidextrous leadership and innovative self-efficacy and between ambidextrous leadership and harmonious work passion.

Originality/value

This study demonstrates the influence of ambidextrous leadership on employees’ innovation behaviour, specifically the role of ambidextrous leadership, and extends the relationship’s theoretical foundation. It is also expected to provide inspiration and serve as a reference for local Chinese management.

Details

Leadership & Organization Development Journal, vol. 45 no. 4
Type: Research Article
ISSN: 0143-7739

Keywords

Access Restricted. View access options
Article
Publication date: 27 February 2023

Jin Yong Park, Changju Kim, Soohyun Park and Kevin Dio

By adopting a cross-country analysis, this study aims to investigate how consumers' perception of book covers affects their online book purchases in terms of feelings of delight…

362

Abstract

Purpose

By adopting a cross-country analysis, this study aims to investigate how consumers' perception of book covers affects their online book purchases in terms of feelings of delight and perceived value of the book.

Design/methodology/approach

The authors tested the hypotheses using a structural equation model using two countries' datasets obtained from 191 Japanese and 207 French consumers.

Findings

The perceived attractiveness of a picture/photo on a book cover can positively influence feelings of delight. Such emotion enhances a book's perceived value, resulting in active online book purchases. Furthermore, when the perceived value of a book is evident, the French are more strongly motivated to purchase books compared to Japanese consumers.

Originality/value

By simultaneously examining emotion and perceived value as an organism, the authors advance the knowledge of the relationship between book covers and online book purchases. In addition, the authors offer evidence that cross-cultural differences (between the French and Japanese) can stimulate different responses to each affective and cognitive internal state, although similar environmental stimuli are provided.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 35 no. 10
Type: Research Article
ISSN: 1355-5855

Keywords

1 – 10 of 369
Per page
102050