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During drilling in coal mines, sticking of drill rod (referred to as SDR in this work) is a potential threat to underground safety. However, no practical measures to deter SDR have been developed yet. The purpose of this study is to develop an anti-SDR strategy using proportional-integral-derivative (PID) and compliance control (PIDC). The proposed strategy is compatible with the drilling process currently used in underground coal mines using drill rigs. Therefore, this study aims to contribute to the PIDC strategy for solving SDR.

A hydraulic circuit to reduce SDR was built based on a load-independent flow distribution system, a PID controller was designed to control the inlet hydraulic pressure of the rotation motor and a typical compliance control approach was adopted to control the feed force and displacement. Moreover, the weight and optimal combination of the alternative admittance control parameters for the feed cylinder were obtained by adopting the orthogonal experiment approach. Furthermore, a fuzzy admittance control approach was proposed to control the feed displacement. Experiments were conducted to test the effectiveness of the proposed method.

The experimental results indicated that the PIDC strategy was appropriate and effective for controlling the rotation motor and feed cylinder; thus, the proposed method significantly reduces the SDR during drilling operations in underground coal mines.

As the PIDC strategy solves the SDR problem in underground coal mines, it greatly improves the safety of coal mine operation and decreases the power cost. Consequently, it brings the considerable benefits of coal mine production and vast application prospects in other corresponding fields. Actual drilling conditions are difficult to accurately simulate in a laboratory; thus, for future work, drilling experiments can be conducted in actual underground coal mines.

The PIDC-based anti-SDR strategy proposed in this study satisfactorily controls the rotation motor and feed cylinder and facilitates the feed and rotation movements. Furthermore, the tangible novelty of this study results is that it improves the frequency response of the entire drilling system. The drilling process with PIDC decreased the occurrence of SDR by 50%; therefore, the anti-SDR strategy can significantly improve the safety and efficiency of underground coal mining.

A numerical study on the aerodynamic noise generation of a high efficiency propeller is carried out.

Three-dimensional numerical simulation based on Reynolds averaged N-S model is performed to obtain the aerodynamic performance of the propeller. Then, the result of the aerodynamic analysis is given as input of the acoustic calculation. The sound is calculated using the Farassat 1A which was derived from Ffowcs Williams–Hawkings equation and is compared with the measurements.

Moreover, the fan is modified for noise reduction by changing its geometrical parameters such as span, chord length and torsion angle.

The variation trend of aerodynamic and acoustic are compared and discussed for different modification tasks. Some meaningful conclusions are drawn on the noise reduction of propeller.

The purpose of the article is to report a study on evaluation of smart manufacturing (SM) performance using a grey theory-based approach.

In total, 30 criteria and 79 attributes for SM performance have been developed. A grey theory-based approach has been used for SM performance evaluation. The grey index has been calculated, and weaker areas have been derived. Performance level of SM has been evaluated using the Euclidean distance approach.

The SM performance index is found to be (3.036, 12.296). The ideal grey performance importance index (GPII) is obtained as (3.025, 4.875). The level of visibility and traceability, vertical integration, lead time and configuration data espionage and control ability are strong performing attributes. Integration abilities of services and manufacturing systems, ability of self-control, worker and raw material productivity, collaboration among buyers and suppliers and dynamic scheduling are identified as weaker areas, and suggestions for improvement have been derived. SM performance level has been identified as “Good.”

Additional performance measures could be included as a part of evaluation. Practitioners can overcome weaker areas in the early phase. Management achieves confidence and practitioners attain success in implementation of SM in industry through the developed SM performance indexing system.

Identification of SM performance measures and analysis of SM performance is the original contribution of the authors. The developed approach assists practitioners and managers to focus more on specific areas for performance improvement.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

This study aims to reveal the triggering mechanism and boundary conditions of tourists’ cross-border travel anxiety (CBTA) from different crisis information sources.

Drawing on the heuristic-systematic model (HSM), this study constructs a theoretical formation path of tourists’ CBTA. Based on competence-based and moral-based crises, hypotheses were examined through three situational experiments, targeting Chinese and Malaysian potential tourists.

Organization-released crisis information triggers higher tourists’ CBTA than government ones, with perceived uncertainty mediating it. Crisis communication message appeals (CCMAs) (rational vs emotional) negatively moderate the above relationships. Rational CCMAs work for governmental crisis communication, while emotional CCMAs work for organizational ones.

This study proposes a heuristic cross-border tourism crisis information dissemination strategy for destination management organizations and highlights the advantages of CCMAs in preventing secondary crises.

This study reexamines the cause-and-effect and the intervention mechanisms of tourists’ reactions to crisis information, which expands the cross-border tourism crisis management research and the application of the HSM in such a context.

本研究旨在从不同的危机信息源中揭示游客跨境旅行焦虑的触发机制和边界条件。

本研究借鉴启发式-系统式模型（HSM）, 构建了游客跨境旅游焦虑的理论形成路径。基于能力型和道德型目的地危机事件, 以中国及马来西亚潜在游客为例, 通过三组情境实验验证所提出的假设。

与政府发布的危机信息相比, 组织发布的危机信息会引发更高的游客跨境旅游焦虑, 而感知不确定性会对该路径起到中介作用。危机沟通信息诉求（理性vs.感性）对上述关系起负向调节作用。理性的信息诉求适用于政府危机沟通, 而感性的信息诉求适用于组织危机沟通。

本研究为目的地管理组织提出了启发式跨境旅游危机信息传播策略, 并强调了危机沟通信息诉求在预防二次危机方面的优势。

本研究重新审视了游客对危机信息反应的因果关系和干预机制, 拓展了跨境旅游危机管理研究和HSM在此背景下的应用。

Este estudio pretende revelar el mecanismo desencadenante y las condiciones límite de la ansiedad de los turistas ante los viajes transfronterizos (CBTA) a partir de diferentes fuentes de información sobre crisis (CIS).

Basándose en el modelo heurístico-sistemático (HSM), este estudio construye una vía teórica de formación de la CBTA de los turistas. A partir de las crisis basadas en la competencia y en la moral, se examinaron las hipótesis mediante tres experimentos situacionales, dirigidos a turistas potenciales chinos y malayos.

La información sobre crisis difundida por organizaciones desencadena una mayor CBTA de los turistas que la gubernamental, con la incertidumbre percibida como mediadora. Los recursos de los mensajes de comunicación de crisis (CCMA) (racionales frente a emocionales) moderan negativamente las relaciones anteriores. Los CCMA racionales funcionan para la comunicación de crisis gubernamental, mientras que los CCMA emocionales para las organizativas.

Los resultados proponen que las organizaciones de gestión de destinos (OGD) deberían considerar estrategias heurísticas a la hora de difundir información sobre crisis turísticas transfronterizas. Prestar atención al efecto diferencial de las CCMA ayuda a prevenir crisis secundarias.

Este estudio reexamina la causa-efecto y los mecanismos de intervención de las reacciones de los turistas a la información sobre crisis, lo que amplía la investigación sobre la gestión de crisis turísticas transfronterizas y la aplicación de la HSM en dicho contexto.

This chapter examines China’s corporate governance and accounting environment that shapes the adoption of internationally acceptable principles and standards. Specifically, it examines international influences, including supranational organizations; foreign investors and international accounting firms; domestic institutional influences, including the political system, economic system, legal system, and cultural system; and accounting infrastructure. China’s convergence is driven by desired efficiency of the corporate sector and legitimacy of participating in the global market. Influenced heavily by international forces in the context of globalization, corporate governance and accounting practices are increasingly becoming in line with internationally acceptable standards and codes. While convergence assists China in obtaining legitimacy, improving efficiency is likely to be adversely affected given that corporate governance and accounting in China operate in an environment that differs considerably from those of Anglo-American countries. An examination of the corporate governance and accounting environment in China suggests heavy government involvement within underdeveloped institutions. While the Chinese government has made impressive progress in developing the corporate governance and accounting environment for the market economy, China’s unique institutional setting is likely to affect how the imported concepts are interpreted and implemented.

The purpose of this paper is to exploit the multiple-Toeplitz matrices reconstruction method combined with quadratic spatial smoothing processing to improve the direction-of-arrival (DOA) estimation performance of coherent signals at low signal-to-noise ratio (SNRs).

An improved multiple-Toeplitz matrices reconstruction method is proposed via quadratic spatial smoothing processing. Our proposed method takes advantage of the available information contained in the auto-covariance matrices of individual Toeplitz matrices and the cross-covariance matrices of different Toeplitz matrices, which results in a higher noise suppression ability.

Theoretical analysis and simulation results show that, compared with the existing Toeplitz matrix processing methods, the proposed method improves the DOA estimation performance in cases with a low SNR. Especially for the cases with a low SNR and small snapshot number as well as with closely spaced sources, the proposed method can achieve much better performance on estimation accuracy and resolution probability.

The study investigates the possibility of reusing pre-existing designs for the DOA estimation of the coherent signals. The proposed technique enables achieve good estimation performance at low SNRs.

The paper includes implications for the DOA problem at low SNRs in communication systems.

The proposed method proved to be useful for the DOA estimation at low SNR.

Different aspects of the globalisation of Chinese basic education have been examined in recent studies. This paper aims to contribute to this research base by examining the relationship between global quality assurance and evaluation (QAEVAL) trends and reforms in the Chinese basic education system.

Relevant research literature in English and Chinese was reviewed to assesses whether a movement of increasing convergence with global QAEVAL policy contents and policy instruments has taken place in China following the introduction of the so-called “equality education”. A guiding theory regarding the basic features of QAEVAL was used to conceptually structure the findings of the authors.

The findings indicate that several subtle convergences are evident in China with global trends in QAEVAL, but a few notable exceptions are also evident.

Albeit the research indicates certain convergence, the authors acknowledge that further research is still needed to examine causal mechanisms of QAEVAL policy convergences and the processes and logic through which global trends are localised.

Both the importance of QAEVAL in global education governance as well as China’s importance to world affairs are increasing. However, so far, the effects of QAEVAL policies on China’s education system have not been thoroughly examined. This paper can serve as a concise starting point for examining the topic more deeply.

Based on the service-profit chain perspective, this study investigates whether service-oriented human resource practices can enhance customer outcomes through motivational mechanisms (i.e. intrinsic/extrinsic satisfaction) as well as emotional mechanisms (i.e. emotional labor strategies).

This study collected paired data from 220 service workers and their customers at different time points from 80 service firms. Multilevel path-analysis was conducted to test the proposed hypotheses.

Our results indicate that firm-level extensive training is positively related to service workers' intrinsic job satisfaction, which in turn increases deep acting. In addition, firm-level incentive compensation is positively associated with service workers' extrinsic job satisfaction, which in turn reduces surface acting. Finally, service employee's deep acting enhances customer loyalty and willingness to recommend via customer satisfaction.

The service organization should (1) stress the importance of incentive compensation to decrease surface acting via enhancing extrinsic job satisfaction and (2) provide extensive service training to improve service employees' intrinsic satisfaction and deep acting, leading to favorable customer outcomes.

The present study identifies the critical roles of motivational and emotional mechanisms in transferring service-oriented human resource practices to customer outcomes and employing rigorous research design to enhance the internal/external validity of our findings.

This research aims to propose a comparative environmental analysis of conventional and prefabricated construction techniques utilizing a building information modelling (BIM) technique.

A set of indicators are selected to assess the environmental emissions throughout the construction life cycle, based on BIM platform. An existing project involving ten apartment buildings in Shanghai is selected as a case study.

The results reveal that prefabricated construction demonstrates environment-friendly performance with some exceptions of acidification and mineral resource consumption. Environmental impacts can also be further reduced by increasing the projected area ratio and percentage of project prefabrication.

Overall, the proposed method can be used to identify relevant environmental merits and for decision-making of appropriate construction techniques in building construction projects.