Wei Qu, Huailiang Zhang, Wei Li, Ling Peng and Wenqian Sun
To improve the transmission efficiency and reduce the damage to pipes in the hydraulic systems of tunnel boring machine subjected to random vibration, this paper aims to propose a…
Abstract
Purpose
To improve the transmission efficiency and reduce the damage to pipes in the hydraulic systems of tunnel boring machine subjected to random vibration, this paper aims to propose a novel dynamic characteristic analysis method that considers random vibration.
Design/methodology/approach
A fluid-structure interaction motion equation of the pipe is established by using Hamilton’s principle. The finite element method and discrete analysis method of random vibration are used to construct a model of the dynamic behavior of the pipe.
Findings
The influences of fluid parameters and external excitation parameters on the dynamic characteristics of pipes are analyzed. The experimental results are found to be in good agreement with the simulation results, which demonstrates that the proposed analytical method can provide a theoretical reference for the design and selection of hydraulic pipes subjected to random vibration.
Originality/value
The proposed method can be regarded as a future calculation method for pipes subjected to random vibration, and the transmission efficiency of the pipe can be improved.
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Fan Liang and Stephen Nicholas
This paper investigates the location determinants of foreign investors and how the location decision‐making impacts on their knowledge transfer strategies. Survey data were…
Abstract
This paper investigates the location determinants of foreign investors and how the location decision‐making impacts on their knowledge transfer strategies. Survey data were collected in Yunnan, a southwest province of China. By examining two different sets of location factors at both the national and provincial levels, the research found that location factors at the provincial level, rather than at the national level, directly influenced foreign investors’ knowledge transfer strategies. The research also found that the support of Yunnan’s local government compensated for the underdeveloped endowment conditions of the province, significantly increasing knowledge transfer of foreign investors. The research suggests that foreign investors need to make appropriate location selection to efficiently exploit their ownership advantages. A well‐structured policy regime is required of host countries in order to encourage knowledge transfer by foreign investors.
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Hannes Velt and Rudolf R. Sinkovics
This chapter offers a comprehensive review the literature on authentic leadership (AL). The authors employ a bibliometric approach to identify, classify, visualise and synthesise…
Abstract
This chapter offers a comprehensive review the literature on authentic leadership (AL). The authors employ a bibliometric approach to identify, classify, visualise and synthesise relevant scholarly publications and the work of a core group of interdisciplinary scholars who are key contributors to the research on AL. They review 264 journal articles, adopting a clustering technique to assess the central themes of AL scholarship. They identify five distinct thematic clusters: authenticity in the context of leadership; structure of AL; social perspectives on AL; dynamism of AL; and value perceptions of AL. Velt and Sinkovics assert that these clusters will help scholars of AL to understand the dominant streams in the literature and provide a foundation for future research.
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Yuri Merizalde, Luis Hernández-Callejo, Oscar Duque-Pérez and Víctor Alonso-Gómez
Despite the wide dissemination and application of current signature analysis (CSA) in general industry, CSA is not commonly used in the wind industry, where the use of vibration…
Abstract
Purpose
Despite the wide dissemination and application of current signature analysis (CSA) in general industry, CSA is not commonly used in the wind industry, where the use of vibration signals predominates. Therefore, the purpose of this paper is to review the use of generator CSA (GCSA) in the online fault detection and diagnosis of wind turbines (WTs).
Design/methodology/approach
This is a bibliographical investigation in which the use of GCSA for the maintenance of WTs is analyzed. A section is dedicated to each of the main components, including the theoretical foundations on which GCSA is based and the methodology, mathematical models and signal processing techniques used by the proposals that exist on this topic.
Findings
The lack of appropriate technology and mathematical models, as well as the difficulty involved in performing actual studies in the field and the lack of research projects, has prevented the expansion of the use of GCSA for fault detection of other WT components. This research area has yet to be explored, and the existing investigations mainly focus on the gearbox and the doubly fed induction generator; however, modern signal treatment and artificial intelligence techniques could offer new opportunities in this field.
Originality/value
Although literature on the use of GCSA for the detection and diagnosis of faults in WTs has been published, these papers address specific applications for each of the WT components, especially gearboxes and generators. For this reason, the main contribution of this study is providing a comprehensive vision for the use of GCSA in the maintenance of WTs.
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Mahamadou Abdou Tankari, Baïlo Camara, Brayima Dakyo and Cristian Nichita
This paper aims to deal with the integration of energy storage devices (ultracapacitors) in wind energy applications to absorb the short terms fluctuations. The originality of…
Abstract
Purpose
This paper aims to deal with the integration of energy storage devices (ultracapacitors) in wind energy applications to absorb the short terms fluctuations. The originality of this contribution is focused on energy management related to wind power frequency distribution between the hybrid sources. The robust and simplified control strategies are proposed and applied to DC‐DC converters without AC signals measurements. A novel MPPT method is introduced to operate the wind generator at the maximum power regardless of the wind speed variations. The fluctuating part of this power is mitigated by using a UC. The reference current of this last is obtained from a low pass filter. An innovative limitation algorithm of the UC voltage is proposed with aims to ensure optimal operation of the system. The control algorithms are implemented in a PIC18F4431 microcontroller. Some experimental results from this new approach are presented and analyzed.
Design/methodology/approach
This study is organized according to the following main and sub‐topics after introduction: frequency distribution principle; wind energy generation; short‐term fluctuations storage system; and experimental setup and results.
Findings
The simulations results highlight the interest of using ultracapacitors in a wind‐diesel system. The experimental results show that the short term fluctuations induced by the wind generator current are effectively mitigated by the ultracapacitors.
Originality/value
In this paper, an interesting MPPT method is presented. The fluctuations mitigation is realised by using the frequency distribution according to ultracapacitors dynamics. The ultracapacitors voltage control method is proposed with the aim of maintaining optimal operation conditions, and is validated by experimental tests.
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Meltem Caber and Tahir Albayrak
– The purpose of this study is to identify the importance of hotel attributes for pre-senior and senior tourists when selecting a hotel.
Abstract
Purpose
The purpose of this study is to identify the importance of hotel attributes for pre-senior and senior tourists when selecting a hotel.
Design/methodology/approach
Three market segments (German, Dutch and British) were selected as the sample of the research. The Callan and Bowman’s (2000) scale was employed and data obtained from 13 five star hotels in Antalya, Turkey.
Findings
Results of the study showed that “value for money” and “availability of organized entertainment in the hotel” were important attributes for senior British tourists when compared to other participants. Dutch senior tourists attached more importance to food service attributes (“small food portions” and “special dietary menus”) than did the other respondents.
Practical implications
Research results confirmed the importance of staff attributes (“politeness of staff” and “friendliness of staff”) for customer satisfaction. This finding highlights the need for training programmes targeting hospitality employees, with a specific focus on meeting customers’ demands for receiving friendly and polite service.
Originality/value
The present study intends to contribute to the literature on senior tourist market by identifying the importance of hotel attributes for three market segments (Germany, England and The Netherlands).
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Veronica Wachong Castro, Nico Heerink, Xiaoping Shi and Wei Qu
The purpose of this paper is to gain more insight into the relationship between off‐farm employment of rural households and water‐saving investments and irrigation water use in…
Abstract
Purpose
The purpose of this paper is to gain more insight into the relationship between off‐farm employment of rural households and water‐saving investments and irrigation water use in rural China.
Design/methodology/approach
Data from a survey held among 317 households in Minle County, Zhangye City, Gansu Province, covering the year 2007, are used for a probit analysis explaining investments in land leveling and for an ordinary least squares regression explaining irrigation water use per mu.
Findings
Off‐farm employment is not significantly related to investments in land leveling, but is negatively associated with water use per mu. In addition, the paper finds that the share of migrant students in a household is positively related to investments in land leveling. The results indicate the presence of major factor market imperfections in the research area, and confirm that the new economics of labor migration (NELM) approach is more relevant for analyzing off‐farm employment and agricultural production in China than neoclassical economic theory.
Originality/value
The paper expands the NELM approach towards the analysis of water‐saving investments and water use. In addition, it distinguishes migrant students as an important category that should be taken into account in analyzing farm household decisions making.
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Shi (Tracy) Xu, Yao-Chin Wang and Emily Ma
Different from the previous organizational citizenship behavior (OCB) literature, this study aims to propose an OCB-O (organizational citizenship behavior toward organizations…
Abstract
Purpose
Different from the previous organizational citizenship behavior (OCB) literature, this study aims to propose an OCB-O (organizational citizenship behavior toward organizations) and OCB-I (organizational citizenship behavior toward individual coworkers) driven mechanism for the formation of OCB-C (organizational citizenship behavior toward customers). Based on the social exchange and agency theories, the authors propose that perceived leadership support and work autonomy contribute to both OCB-I and OCB-O, which contributes to proactive and reactive customer service attitude as well as OCB-C.
Design/methodology/approach
A three-wave survey was conducted in five-star hotels in Mainland China, and a sample of 410 hotel frontline employees was used to test the model.
Findings
Findings of the study suggested that perceived leadership support positively led to OCB-O and OCB-I while work autonomy led to OCB-I, demonstrating the importance of employees’ perceived leadership support on motivating employees to perform OCB-I and OCB-O. OCB-I and OCB-O directly improved OCB-C, confirming the proposed spillover effect from OCB-I and OCB-O to OCB-C. OCB-I supported both proactive and reactive customer service attitudes, revealing OCB-I as more effective than OCB-O on influencing employees’ service attitudes. Furthermore, OCB-I, OCB-O and proactive customer service attitude lead to OCB-C.
Practical implications
This study suggests that it is important for leaders to show care and support to employees and design jobs with a certain level of flexibility, so that employees are motivated to go the extra mile to do a good job. When employees make helping others a habit, they will provide more genuine care to customers and do a better job in serving customers.
Originality/value
This study supports the spillover mechanism of OCB-I and OCB-O on OCB-C. Specifically, the spillover mechanism starts from a workplace-driven model with employees’ perceived leadership support and work autonomy to enhance OCB-O as well as OCB-I. Then, spillover effects stem directly from OCB-I and OCB-O to OCB-C and indirectly to proactive customer service attitude.
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Abstract
Purpose
This paper aims to review policy innovations in China for addressing the graduate unemployment crisis that has been created by the expansion of higher education in the past decade.
Design/methodology/approach
The authors draw on government documents, research findings, and mass media reports to highlight the key measures of the Chinese government to alleviate the over‐education problem and to improve college graduates' employment prospects.
Findings
The review describes government efforts both at the institutional level to enhance student employability and at the national level to create alternative employment channels. The Chinese experiences show that the challenges posed by the graduate employment crisis may turn out to be a new opportunity to reform higher education in order to better address the needs unique to a country's own society.
Social implications
The review of the Chinese case will inspire policy makers in other countries to seek alternative routes for the development of their own higher education.
Originality/value
This is the first study of its kind to address the recent policy innovations and their implications for potential reform.
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Abstract
Purpose
The purpose of this paper is to explore the heterogeneity and correlations of agricultural greenhouse gas (GHG) emissions among provinces in China, and then policy implications are proposed.
Design/methodology/approach
After agricultural GHG accounting and a pre-analysis of inter-provincial heterogeneity, improved gravity model and the Social Network Analysis (SNA) methods are introduced to construct the network, being carried out from three aspects of the whole network, individual provincial characteristics and cluster analysis.
Findings
(1) There are significant regional variations in agricultural GHG scale among provinces owing to the layout of agricultural production, and the temporal trends show that the direction and speed of agricultural GHG scale change vary among provinces; (2) In terms of inter-provincial correlations, there exists a complex spatial network of agricultural GHG among provinces, which tends to be more complex, intensive and stable, while the status of the provinces in the network also has gradually become more balanced. All provinces played their respective roles in the four clusters of the network with agricultural layout and comparative advantages, and the distribution has continuously optimized.
Practical implications
The inter-provincial network characteristics of agricultural GHG emissions and its evolution have practical implications for differentiated and coordinated agricultural GHG reduction policies at the provincial levels.
Originality/value
This paper innovatively study inter-provincial agricultural GHG correlations in China with the SNA methods used to study economic and social connections in the past. There is some originality in the introduction of network theory and application of the SNA methods, which can provide some reference for researches in similar fields.