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1 – 10 of over 2000Tao Lin, Yaning Li, Rongjin Zhao, Zekun Ma and Jianan Xie
This paper aims to improve the device performance from the perspective of reducing ohmic contact resistance; the effects of different electrode structures and alloying parameters…
Abstract
Purpose
This paper aims to improve the device performance from the perspective of reducing ohmic contact resistance; the effects of different electrode structures and alloying parameters on the series resistance and power-current-voltage of laser diodes (LDs) have been investigated in this paper.
Design/methodology/approach
Four groups of p-GaAs side metal electrodes with different metal layer arrangements and thicknesses are fabricated for the investigated LDs. The investigated p-GaAs side electrodes are based on Ti/Pt/Au material and the n-GaAs side metal electrodes all have a same structure of Ni/Ge/Ni/Au/Ti/Pt/Au. The LDs with different electrodes were alloyed at 380°C for 60 s and 420°C for 80 s.
Findings
The experimental results show that the series resistance decreases by 14%–20%, the output power increases by 2%–2.2% and the conversion efficiency increases by 1.69%–2.16% for the LDs prepared with optimized alloying parameters (420°C for 80 s). The laser diode with p-GaAs side Ti/Pt/Au electrode of 30/70/100 nm has the best device characteristics under both annealing conditions.
Originality/value
The utilization of this improvement on ohmic contact property in electrode is not only very important for upgrading high-power LDs but also helpful for GaAs-based microelectronic devices such as HBT and monolithic microwave integrated circuit.
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Latif Cem Osken, Ceylan Onay and Gözde Unal
This paper aims to analyze the dynamics of the security lending process and lending markets to identify the market-wide variables reflecting the characteristics of the stock…
Abstract
Purpose
This paper aims to analyze the dynamics of the security lending process and lending markets to identify the market-wide variables reflecting the characteristics of the stock borrowed and to measure the credit risk arising from lending contracts.
Design/methodology/approach
Using the data provided by Istanbul Settlement and Custody Bank on the equity lending contracts of Securities Lending and Borrowing Market between 2010 and 2012 and the data provided by Borsa Istanbul on Equity Market transactions for the same timeframe, this paper analyzes whether stock price volatility, stock returns, return per unit amount of risk and relative liquidity of lending market and equity market affect the defaults of lending contracts by using both linear regression and ordinary least squares regression for robustness and proxying the concepts of relative liquidity, volatility and return constructs by more than variable to correlate findings.
Findings
The results illustrate a statistically significant relationship between volatility and the default state of the lending contracts but fail to establish a connection between default states and stock returns or relative liquidity of markets.
Research limitations/implications
With the increasing pressure for clearing security lending contracts in central counterparties, it is imperative for both central counterparties and regulators to be able to precisely measure the risk exposure due to security lending transactions. The results gained from a limited set of lending transactions merit further studies to identify non-borrower and non-systemic credit risk determinants.
Originality/value
This is the first study to analyze the non-borrower and non-systemic credit risk determinants in security lending markets.
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Di Wu, Huabin Chen, Yinshui He, Shuo Song, Tao Lin and Shanben Chen
The purpose of this paper is to investigate the relationship between the keyhole geometry and acoustic signatures from the backside of a workpiece. It lays a solid foundation for…
Abstract
Purpose
The purpose of this paper is to investigate the relationship between the keyhole geometry and acoustic signatures from the backside of a workpiece. It lays a solid foundation for monitoring the penetration state in variable polarity keyhole plasma arc welding.
Design/methodology/approach
The experiment system is conducted on 6-mm-thick aluminum alloy plates based on a dual-sensor system including a sound sensor and a charge coupled device (CCD) camera. The first step is to extract the keyhole boundary from the acquired keyhole images based on median filtering and edge extraction. The second step is to process the acquired acoustic signal to obtain some typical time domain features. Finally, a prediction model based on the extreme learning machine (ELM) technique is built to recognize different keyhole geometries through the acoustic signatures and then identify the welding penetration status according to the recognition results.
Findings
The keyhole geometry and acoustic features after processing can be closely related to dynamic change information of keyhole. These acoustic features can predict the keyhole geometry accurately based on the ELM model. Meanwhile, the predict results also can identify different welding penetration status.
Originality/value
This paper tries to make a foundation work to achieve the monitoring of keyhole condition and penetration status through image and acoustic signals. A useful model, ELM, is built based on these features for predicting the keyhole geometry. Compared with back-propagating neural network and support vector machine, this proposed model is faster and has better generalization performance in the case studied in this paper.
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Jing Qi, Catherine Manathunga, Michael Singh and Tracey Bunda
The purpose of this paper is to provide a micro historical account of the work of a key Chinese educational reformer, Tao Xingzhi (1891–1946), who transformed educational ideas…
Abstract
Purpose
The purpose of this paper is to provide a micro historical account of the work of a key Chinese educational reformer, Tao Xingzhi (1891–1946), who transformed educational ideas from John Dewey to effect social and cultural change in 1920s–1940s China.
Design/methodology/approach
This paper examines English and Chinese language sources, including Tao’s poetry, to present a fresh analysis of Tao’s epistemological life history. It draws upon transnational historical approaches to chart the multidirectional circulation of progressive education philosophies around the globe. It also explores some conceptual dimensions of Chinese historical thinking and historiographical strategies.
Findings
Tao Xingzhi engaged in critical intercultural knowledge exchange in implementing educational reforms in China. He blended and critiqued Chinese and Deweyian educational philosophies to create unique educational reform, which involved reversing some of Dewey’s approaches as well as adapting others.
Originality/value
This paper foregrounds Tao Xingzhi’s agency in transforming some of Dewey’s ideas in the Chinese context and challenges studies that adopt an “impact-response” approach to Tao’s contribution, which suggest a one-way flow of knowledge from a “modern” West to a “traditional” China. It brings hitherto unexplored Chinese language sources to an English-speaking audience, particularly Tao’s poetry, to gain new historical insights into Tao’s educational reforms. It contributes to transnational understandings of the multidirectional flows of knowledge about Progressive educational philosophies around the world.
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Sifeng Liu, Yong Tao, Naiming Xie, Liangyan Tao and Mingli Hu
The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it…
Abstract
Purpose
The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it commemorates the 40th anniversary of the birth of grey system theory and the 10th anniversary of Grey Systems–Theory and Application.
Design/methodology/approach
Firstly, the innovations of theoretical research in grey system theory were summarized and some of the widely recognized new results are briefly described. By searching and combing the research results of grey system theory in China national knowledge infrastructure (CNKI) database and Web of Science by Institute for Scientific Information (ISI), this paper shows the rapid development trend of grey system theory in the past 40 years, and the successful applications of grey system theory in the fields of social sciences, natural sciences and engineering technologies.
Findings
More than 227 thousands literature were found by input 10 phrases such as grey system, grey number and sequence operator etc. in CNKI database. After entering the new century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year and more than 15 thousands papers have been included per year since 2014. Grey system method and model are widely used in physics, chemistry, biology and other fields of natural science, as well as transportation, electric power, machinery and other fields of engineering technology, and a large number of valuable results have been achieved.
Practical implications
It can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development and high-level talent training from tens of thousands of literatures marked with important national science and technology projects and a large number of grey system literatures published by China’s double first-class universities and double first-class discipline construction universities.
Originality/value
Both innovations of theoretical research and practical application play important role in the growth of new theory. The innovations of theoretical research provide methods and tools for practical application, which is conducive to improve application efficiency and broaden application fields. A large number of practical applications needs have become the source of theoretical innovation and the solid background for the birth of theoretical innovation achievements.
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Examines the fifteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…
Abstract
Examines the fifteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.
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Jan Brzozowski and Marco Cucculelli
The purpose of this study is to analyze the determinants of transnational business ties (i.e. ties with the country of origin) and to investigate their impact on the economic…
Abstract
Purpose
The purpose of this study is to analyze the determinants of transnational business ties (i.e. ties with the country of origin) and to investigate their impact on the economic performance of immigrant firms.
Design/methodology/approach
Based on the representative survey conducted among 259 foreign-born immigrant entrepreneurs in Marche region (Central Italy), the study investigates the determinants of having transnational ties with countries of origin. Then it compares the effect of transnational ties and the effect of alternative domestic ethnic business ties on the performance of immigrant firms.
Findings
This study demonstrates that having transnational ties is more likely for individuals with former entrepreneurial experience in the home countries and with higher education acquired in Italy. The performance of immigrant firms in the 2014–2016 period (measured by the level of revenues) is positively related to transnational ties – this effect is very strong and significant. On the other hand, reliance on the domestic ethnic ties (i.e. ties with co-ethnic population in Italy) is one of the key factors that inhibits further growth of immigrant enterprises.
Originality/value
This study advances the understanding of how immigrant entrepreneurs create transnational business ties with their home countries. Additionally, this research contributes to the existing literature on immigrant entrepreneurship, by explaining the role of heterogeneous business ties: transnational connections, domestic ties with co-ethnic partners and ties with individuals from native population (in this case: Italy) for the entrepreneurial performance. Consequently, it offers recommendations for policy-makers willing to encourage entrepreneurial activities of immigrants in host countries and to their counterparts in home countries, who are planning to use the advantage diaspora entrepreneurial potential for the benefit of their economies.
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Hai Lin, Xinyuan Stacie Tao, Junbo Wang and Chunchi Wu
This chapter examines momentum in the corporate bond market using a comprehensive data set that includes bonds with different characteristics and provisions. We find that momentum…
Abstract
This chapter examines momentum in the corporate bond market using a comprehensive data set that includes bonds with different characteristics and provisions. We find that momentum exists in a wide range of corporate bonds. The momentum effect is more significant for callable bonds and lower-rated bonds. This effect cannot be explained by standard risk factors and liquidity in the bond market. Bond momentum prevails over time and remains strong even after the corporate bond market becomes more transparent and liquid with establishment of TRACE. The high magnitude of momentum profits casts doubt that they can be explained by risk-based theories.
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Ming K. Lim, Weiqing Xiong and Chao Wang
In the last decade, cloud manufacturing (CMfg) has attracted considerable attention from academia and industry worldwide. It is widely accepted that the design and analysis of…
Abstract
Purpose
In the last decade, cloud manufacturing (CMfg) has attracted considerable attention from academia and industry worldwide. It is widely accepted that the design and analysis of cloud manufacturing architecture (CMfg-A) are the basis for developing and applying CMfg systems. However, in existing studies, analysis of the status, development process and internal characteristics of CMfg-A is lacking, hindering an understanding of the research hotspots and development trends of CMfg-A. Meanwhile, effective guidance is lacking on the construction of superior CMfg-As. The purpose of this paper is to review the relevant research on CMfg-A via identification of the main layers, elements, relationships, structure and functions of CMfg-A to provide valuable information to scholars and practitioners for further research on key CMfg-A technologies and the construction of CMfg systems with superior performance.
Design/methodology/approach
This study systematically reviews the relevant research on CMfg-A across transformation process to internal characteristics by integrating quantitative and qualitative methods. First, the split and reorganization method is used to recognize the main layers of CMfg-A. Then, the transformation process of six main layers is analysed through retrospective analysis, and the similarities and differences in CMfg-A are obtained. Subsequently, based on systematic theory, the elements, relationships, structure and functions of CMfg-A are inductively studied. A 3D printing architecture design case is conducted to discuss the weakness of the previous architecture and demonstrate how to improve it. Finally, the primary current trends and future opportunities are presented.
Findings
By analyzing the transformation process of CMfg-A, this study finds that CMfg-A resources are developing from tangible resources into intangible resources and intelligent resources. CMfg-A technology is developing from traditional cloud computing-based technology towards advanced manufacturing technology, and CMfg-A application scope is gradually expanding from traditional manufacturing industry to emerging manufacturing industry. In addition, by analyzing the elements, relationships, structure and functions of CMfg-A, this study finds that CMfg-A is undergoing a new generation of transformation, with trends of integrated development, intelligent development, innovative development and green development. Case study shows that the analysis of the development trend and internal characteristics of the architecture facilitates the design of a more effective architecture.
Research limitations/implications
This paper predominantly focuses on journal articles and some key conference papers published in English and Chinese. The reason for considering Chinese articles is that CMfg was proposed by the Chinese and a lot of Chinese CMfg-A articles have been published in recent years. CMfg is suitable for the development of China’s manufacturing industry because of China’s intelligent manufacturing environment. It is believed that this research has reached a reliable comprehensiveness that can help scholars and practitioners establish new research directions and evaluate their work in CMfg-A.
Originality/value
Prior studies ignore the identification and analysis of development process and internal characteristics for the current development of CMfg-A, including the main layers identification of different CMfg-As and the transformation process analysis of these main layers, and in-depth analysis of the inner essence of CMfg-A (such as its elements, relationships, structure and functions). This study addresses these limitations and provides a comprehensive literature review.
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