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Book part
Publication date: 31 May 2016

Jia Yan, Xiaowen Fu, Tae Hoon Oum and Kun Wang

This chapter reviews the key results obtained in previous studies of airline mergers. It is found that the effect of mergers on airfares is dependent on the network…

Abstract

This chapter reviews the key results obtained in previous studies of airline mergers. It is found that the effect of mergers on airfares is dependent on the network configurations of merging airlines. Fare increases are frequently observed on overlapped routes. However, if the networks of two merging airlines are complementary, the expanded network after the merger leads to cost savings, increase in travel options, and improvement in service quality. Therefore, in a deregulated market, with few entry barriers, relaxing merger regulations is likely to improve welfare. However, most welfare evaluations do not incorporate quality changes or dynamic competition effects. Empirical investigations are primarily ex post analysis of mergers that have already passed antitrust reviews. The relationship between market concentration and welfare might be nonlinear and market specific. Therefore, airline mergers and alliances should be reviewed case by case. Methodological improvements are needed in future studies to control for the effects of complicating factors inherent in ex post evaluations.

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Airline Efficiency
Type: Book
ISBN: 978-1-78560-940-4

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Article
Publication date: 18 January 2016

Jia Yan, Shukai Duan, Tingwen Huang and Lidan Wang

The purpose of this paper is to improve the performance of E-nose in the detection of wound infection. Feature extraction and selection methods have a strong impact on the…

Abstract

Purpose

The purpose of this paper is to improve the performance of E-nose in the detection of wound infection. Feature extraction and selection methods have a strong impact on the performance of pattern classification of electronic nose (E-nose). A new hybrid feature matrix construction method and multi-objective binary quantum-behaved particle swarm optimization (BQPSO) have been proposed for feature extraction and selection of sensor array.

Design/methodology/approach

A hybrid feature matrix constructed by maximum value and wavelet coefficients is proposed to realize feature extraction. Multi-objective BQPSO whose fitness function contains classification accuracy and a number of selected sensors is used for feature selection. Quantum-behaved particle swarm optimization (QPSO) is used for synchronization optimization of selected features and parameter of classifier. Radical basis function (RBF) network is used for classification.

Findings

E-nose obtains the highest classification accuracy when the maximum value and db 5 wavelet coefficients are extracted as the hybrid features and only six sensors are selected for classification. All results make it clear that the proposed method is an ideal feature extraction and selection method of E-nose in the detection of wound infection.

Originality/value

The innovative concept improves the performance of E-nose in wound monitoring, and is beneficial for realizing the clinical application of E-nose.

Details

Sensor Review, vol. 36 no. 1
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 24 November 2020

Pingping He, Feng Gao, Yan Li, Wenwu Wu and Dongya Zhang

The purpose of this paper is to research on optimization of spindle bearing preload based on efficiency coefficient method and provide theoretical guidance for variable…

Abstract

Purpose

The purpose of this paper is to research on optimization of spindle bearing preload based on efficiency coefficient method and provide theoretical guidance for variable preload of intelligent spindle.

Design/methodology/approach

Based on an established thermo-mechanical coupling model of angular contact ball bearing with fix-position preload, temperature rise and axial stiffness of the bearing at different speeds and preload are analyzed, and life of the bearing is estimated by the improved L-P theory. The bearing temperature rise, axial stiffness and life data are standardized, and the preload is optimized by the efficiency coefficient method according to the requirements of operating conditions.

Findings

The optimized preload meets comprehensive requirements of the bearing temperature rise, axial stiffness and life under different operating conditions.

Originality/value

In the past studies, it is rarely reported that temperature rise, stiffness and life of the bearing under thermo-mechanical coupling effect are used as objective functions to optimize preload at different speeds.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2020-0205/

Details

Industrial Lubrication and Tribology, vol. 73 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 6 December 2018

Zhen Yan, Dong Jiang, Xiaoming Gao, Can Zhang, Ming Hu, Dapeng Feng, Jiayi Sun, Lijun Weng and Chao Wang

This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether…

Abstract

Purpose

This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether) and SiCH (silahydrocarbons) oils with different hydrocarbon chains were used, respectively. Lubricating mechanism of the composite system was also explored.

Design/methodology/approach

The tribological behaviors of the WS2 films against the PPI cylindrical pins before and after immersing oil were evaluated under different loads by a reciprocating-type ball-on-disc tribometer.

Findings

The composite system exhibited the low and stable friction coefficient after the running-in stage, and the lubricant oil played a positive effect. It was found that the WS2/PFPE composite system exhibited more excellent lubricating property, although sole SiCH far exceeds PFPE in lubrication. The abnormal phenomenon mainly resulted from the influence of the oil amount. XRD results on the wear track surfaces indicated that PFPE and SiCH oils with different hydrocarbon chains were likely to preferentially adsorb to the edge plane and basal plane of the WS2 crystals, respectively.

Originality/value

In previous studies, liquid lubricants were directly dripped or spin-coated on the solid lubricant surface. Based on its potential advantage in application, the tribological behavior and mechanism of the solid lubricating film/oil-impregnated PPI composite system were investigated in this study.

Details

Industrial Lubrication and Tribology, vol. 71 no. 3
Type: Research Article
ISSN: 0036-8792

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Abstract

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Chinese Social Media
Type: Book
ISBN: 978-1-83909-136-0

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Book part
Publication date: 31 May 2016

Abstract

Details

Airline Efficiency
Type: Book
ISBN: 978-1-78560-940-4

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Article
Publication date: 27 September 2018

Lan Ye, Wei Yang and Weiming Lin

This paper aims to share some experiences and practical activities related to the use and management of usage data in the Digital Resource Acquisition Alliance of Chinese…

Abstract

Purpose

This paper aims to share some experiences and practical activities related to the use and management of usage data in the Digital Resource Acquisition Alliance of Chinese Academic Libraries (DRAA) as a reference for library consortia engaged in providing usage statistics services of e-resources to member libraries.

Design/methodology/approach

A literature review and online survey are used to analyze the research and practice of e-resources usage statistics conducted internationally. The case of DRAA is introduced to present how DRAA develops usage statistics services and promotes the implementation of the Standardized Usage Statistics Harvesting Initiative (SUSHI) to deliver usage statistics to member libraries. Future developments and enhancements are also described.

Findings

The main actions taken by DRAA to develop usage statistics services are as follows: development of the DRAA Usage Statistics Portal to provide a single point of access to usage statistics from participating publishers on behalf of member libraries; development of a SUSHI client, taking the lead in promoting SUSHI implementation to automatically obtain usage statistics in Chinese academic libraries; establishment of a working group on usage statistics and the China Academic Library and Information System/DRAA Standards and Recommended Practices Research Task Group to form a long-term mechanism for monitoring and gathering usage statistics; and strengthening of the understanding and application of standards and best practices for libraries and vendors in China. Scheduled enhancements in the future include a deep analysis and utilization of usage statistics, the promotion of Counting Online Usage of NeTworked Electronic Resources and SUSHI to Chinese academic resource publishers and raising awareness about normalizing usage statistics.

Originality/value

This paper has pertinence and wider implications for library consortia engaged in providing e-resources usage statistics services to member libraries.

Details

The Electronic Library, vol. 36 no. 6
Type: Research Article
ISSN: 0264-0473

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Article
Publication date: 8 April 2021

Zonghua Liu, Yulang Guo, Junyun Liao, Yanping Li and Xu Wang

Despite past studies revealed the positive effect of corporate social responsibility (CSR) on consumer advocacy behavior, little research has paid attention to employee…

Abstract

Purpose

Despite past studies revealed the positive effect of corporate social responsibility (CSR) on consumer advocacy behavior, little research has paid attention to employee advocacy behavior. This research aims to examine the relationship between CSR and employee advocacy behavior, the mediating role of meaningful work as well as the moderating effect of person–supervisor fit on CSR perception – meaningful work relationship.

Design/methodology/approach

This study used 263 employee samples to examine the relationship between CSR and employee advocacy behavior and its influence mechanism. Hierarchical regression analyses and bootstrap approach were applied to analyze the data.

Findings

The results show that CSR perception is positively related to employee advocacy behavior, meaningful work mediates the link between CSR perception and employee advocacy behavior, and the strength of the relationship between CSR perception and meaningful work depends on person–supervisor fit.

Research limitations

This study only investigated the effect of perceived CSR on employee advocacy behavior, future studies should explore the alternative mediation mechanism through which external/internal CSR perception or different CSR dimensions influence employee advocacy behavior.

Practical implications

This study has practical implications for organizational managers. First, firms should undertake CSR practices and make employee interpret them in a right way. Second, meaningful work is of significance for employees and training and development, challenging jobs and job rotation are conducive to create a sense of meaning in employees’ work.

Originality/value

This study discussed how and when CSR influences employee advocacy in the Chinese context.

Details

Chinese Management Studies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1750-614X

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Abstract

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Airline Efficiency
Type: Book
ISBN: 978-1-78560-940-4

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Article
Publication date: 29 March 2021

Xiaoyue Chen, Bin Li and Andrew C. Worthington

The purpose of this paper is to examine the relationships between the higher moments of returns (realized skewness and kurtosis) and subsequent returns at the industry…

Abstract

Purpose

The purpose of this paper is to examine the relationships between the higher moments of returns (realized skewness and kurtosis) and subsequent returns at the industry level, with a focus on both empirical predictability and practical application via trading strategies.

Design/methodology/approach

Daily returns for 48 US industries over the period 1970–2019 from Kenneth French’s data library are used to calculate the higher moments and to construct short- and medium-term single-sort trading strategies. The analysis adjusts returns for common risk factors (market, size, value, investment, profitability and illiquidity) to confirm whether conventional asset pricing models can capture these relationships.

Findings

Past skewness positively relates to subsequent industry returns and this relationship is unexplained by common risk factors. There is also a time-varying effect in which the predictive role of skewness is much stronger over business cycle expansions than recessions, a result consistent with varying investor optimism. However, there is no significant relationship between kurtosis and subsequent industry returns. The analysis confirms robustness using both value- and equal-weighted returns.

Research limitations/implications

The calculation of realized moments conventionally uses high-frequency intra-day data, regrettably unavailable for industries. In addition, the chosen portfolio-sorting method may omit some information, as it compares only average group returns. Nonetheless, the close relationship between skewness and future returns at the industry level suggests variations in returns unexplained by common risk factors. This enriches knowledge of market anomalies and questions yet again weak-form market efficiency and the validity of conventional asset pricing models. One suggestion is that it is possible to significantly improve the existing multi-factor asset pricing models by including industry skewness as a risk factor.

Practical implications

Given the relationship between skewness and future returns at the industry level, investors may predict subsequent industry returns to select better-performing funds. They may even construct trading strategies based on return distributions that would generate abnormal returns. Further, as the evaluation of individual stocks also contains industry information, and stocks in industries with better performance earn higher returns, risks related to industry return distributions can also shed light on individual stock picking.

Originality/value

While there is abundant evidence of the relationships between higher moments and future returns at the firm level, there is little at the industry level. Further, by testing whether there is time variation in the relationship between industry higher moments and future returns, the paper yields novel evidence concerning the asymmetric effect of stock return predictability over business cycles. Finally, the analysis supplements firm-level results focusing only on the decomposed components of higher moments.

Details

Review of Accounting and Finance, vol. 20 no. 1
Type: Research Article
ISSN: 1475-7702

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