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In the current teleoperation system of humanoid robots, the control between arms and the control between the waist and arms are individual and lack coordinated motion. This paper aims to solve the above problem and proposes a teleoperation control approach for a humanoid robot based on waist–arm coordination (WAC).

The teleoperation approach based on WAC comprises dual-arm coordination (DAC) and WAC. The DAC method realizes the coordinated motion of both arms through one hand by establishing a mapping relationship between a single hand controller and the manipulated object; the WAC method realizes the coordinated motion of both arms and waist by calculating the inverse kinematic input of robotic arms based on the desired velocity of the waist and the end of both arms. An integrated teleoperation control framework provides interfaces for the above methods, and users can switch control modes online to adapt to different tasks.

After conducting experiments on the dual-arm humanoid robot through the teleoperation control framework, it was found that the DAC method can save 27.2% of the operation time and reduce 99.9% of the posture change of the manipulated object compared with the commonly used individual control. The WAC method can accomplish a task that cannot be done by individual control. The experiments proved the improvement of both methods in terms of operation efficiency, operation stability and operation capability compared with individual control.

The DAC method better maintains the constraints of both arms and the manipulated object. The WAC method better maintains the constraints of the manipulated object itself. Meanwhile, the teleoperation framework integrates the proposed methods and enriches the teleoperation modes and control means.

The purpose of this paper is to propose a smooth double-spline interpolation method for six-degree-of-freedom rotational robot manipulators, achieving the global C2 continuity of the robot trajectory.

This paper presents a smooth double-spline interpolation method, achieving the global C2 continuity of the robot trajectory. The tool center positions and quaternion orientations are first fitted by a cubic B-spline curve and a quartic-polynomial-based quaternion spline curve, respectively. Then, a parameter synchronization model is proposed to realize the synchronous and smooth movement of the robot along the double spline curves. Finally, an extra u-s function is used to record the relationship between the B-spline parameter and its arc length parameter, which may reduce the feed rate fluctuation in interpolation. The seven segments jerk-limited feed rate profile is used to generate motion commands for algorithm validation.

The simulation and experimental results demonstrate that the proposed method is effective and can generate the global C2-continuity robot trajectory.

The main contributions of this paper are as follows: guarantee the C2 continuity of the position path and quaternion orientation path simultaneously; provide a parameter synchronization model to realize the synchronous and smooth movement of the robot along the double spline curves; and add an extra u-s function to realize arc length parameterization of the B-spline path, which may reduce the feed rate fluctuation in interpolation.

The purpose of this study is to investigate how and why formal mentoring support reduces newcomers' intention to leave from the perspective of uncertainty reduction theory.

Time-lagged data were collected from two sources, mentors and newcomers, and 193 paired data sets were included in the analysis.

The results showed that formal mentoring support was positively related to newcomers' person–organisation fit (P–O fit) and person–job fit (P–J fit). In addition, P–O fit and P–J fit mediated the relationship between formal mentoring support and newcomers' intention to leave. Moreover, newcomers' uncertainty avoidance orientation strengthened the relationship between formal mentoring support and perception of fit, and it strengthened the indirect effect between formal mentoring support and newcomer's intention to leave, via the perception of fit.

This study enhances our understanding of the underlying mechanism between formal mentoring support and newcomers' intention to leave. Moreover, it demonstrates that uncertainty avoidance orientation is an important boundary condition during the process of organisational socialisation. The findings also contribute to the organisational socialisation and the mentoring literature by providing evidence from a blue-collar sample.

This work aims to demonstrate the vibration suppression of the rotor system with localized defects on bearing using an integral squeeze film damper (ISFD).

Experiments were carried out to study the vibration characteristics of the rotor system with ISFD mounted on fault deep groove ball bearings. Three fault bearings including bearing with outer race defect, inner race defect and ball defect have been used in this paper. The results were compared by use of vibration acceleration level, continuous wavelet transform and envelope spectrum.

It was found that ISFD shows excellent damping and vibration attenuation characteristics of the rotor system with defective bearing. The fault bearing rotor system with external ISFD considerably reduces the vibration energy and amplitude compared with the system without ISFD.

There is a dearth of experimental research pertaining to vibration characteristics of rotor system support by defective bearings with ISFD. Besides, the test provides evidence for the application of ISFD in vibration control of the rotor system with incipient defects on bearing.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0144/

This study aims to present a novel hydrostatic squeeze film-metal mesh journal bearing (HS-MMJB), which uses both hydrostatic squeeze film damper (HSFD) and metal mesh damper (MMD), to suppress the vibration of rotor-bearing systems.

The lubrication equations were introduced to calculate the dynamic characteristics of HS-MMJB, and the response analyses of rotor systems were carried out. Experiments were conducted to study the vibration reduction of a rotor system with HS-MMJB. In addition, experiments for different oil supply pressures in the HS-MMJB were conducted.

The theoretical and experimental results show that the HS-MMJB exhibits excellent damping and vibration attenuation characteristics. Moreover, the stability of the rotor system can be improved by controlling the oil supply pressure.

There is a dearth of research on vibration characteristics of rotor system support by journal bearing combining HSFD and MMD. Moreover, the active oil pressure control is implemented to improve the stability of rotor system.

Global mobile communication is one of the most dynamic and important service markets. Several researchers suggest using a theoretical approach to develop a much deeper insight into key marketing constructs such as service quality, customer perceived value, customer satisfaction, perceived switching costs, corporate image, and customer loyalty is of vital importance to the mobile communications market. This study aims to develop and test a comprehensive hierarchical model of these six important constructs. The model also incorporates the retailing function of a major mobile communication provider.

The research sample of 516 was drawn from customers of one of the largest mobile communications service providers in China. The data were analysed using exploratory factor analysis, confirmatory factor analysis and structural equation modelling.

The results of the study support using a hierarchical and multidimensional approach for conceptualising and measuring customers' perceptions of service quality in the mobile communications market. In addition, the findings illustrate that service quality is an important determinant of customer perceived value, customer satisfaction, corporate image, and perceived switching costs. Customer perceived value is also an antecedent of customer satisfaction. Corporate image, customer satisfaction, and perceived switching costs are three key drivers of customer loyalty. However, the findings also indicate that corporate image is not an important determinant of customer satisfaction and that customer perceived value is not a key driver of customer loyalty.

This is the first paper that has developed and tested a comprehensive hierarchical model of the mobile communications market.

The purpose of this paper is to define the concept of guanxi deviant behaviour (GDB) initially on the basis of a theoretical study of guanxi, guanxi behaviour and workplace deviant behaviour and to analyse the influence of GDB and the relationship between GDB and counterproductive work behaviour.

This study collects interview data from 30 enterprise executives, summarises relevant literature from four major databases (two in English and two in Chinese) and applies a grounded theory methodology to refine and further define the core category of GDB, and the main category is interpreted and validated using triangulation.

The three dimensions of GDB are guanxi bribery behaviour, irregular connected transaction behaviour and guanxi allied behaviour. There are links amongst the three dimensions, no dimension has an independent existence and that is not the end of the GDB issue. Generally, the occurrence of a kind of GDB can be construed to be a preparation for the implementation of another kind, and the latter is the real purpose of the perpetrators.

This paper is expected to attract the attention of managers and improve the ability of recognising, preventing and punishing GDB.

This study not only enriches organisational behaviour theory but also enhances the awareness of, and insights into, the negative effects of guanxi.

The purpose of this paper is to offer novel insights into: knowledge of proto-feminism through description and analysis of the rule of the seventh century female Emperor Wu Zetian; postcolonial theory by revealing the existence and proto-feminist activities of a non-western female leader; and the literature on gender and invisibility through a study of a leading figure that is relatively unknown to western feminists and is even, in feminist terms, something of a neglected figure.

In order to examine Wu’s proto-feminist practices as recorded in historical materials, we use critical hermeneutics as a tool for textual interpretation, through the following four stages: choosing texts from historical records and writings of Wu; analyzing the historical sociocultural context; analyzing the relationship between the text and the context; and offering a conceptual framework as a richer explanation.

Wu’s life activities demonstrate proto-feminism in late seventh century China in at least four aspects: gender equality in sexuality, in social status, in politics, and women’s pursuit of power and leadership.

Future research may dig into the paradox of Wu’s proto-feminist practices, the relationship between organizational power and feminism/proto-feminism, and the ways in which Wu’s activities differ from other powerful women across cultures, etc.

The study encourages a rethink of women and leadership style in non-western thought.

The study supports Calás and Smircich’s 2005 call for greater understanding of feminist thought outside of western thought and a move to transglobal feminism.

This study recovers long lost stories of women leadership that are “invisible” in many ways in the historical narratives, and contributes to postcolonial feminism by revealing the existence of indigenous proto-feminist practice in China long before western-based feminism and postcolonial feminism emerged.

The purpose of this paper is to describe and discuss the use of Chinese medicine in the prevention and treatment of coronavirus disease 2019 (COVID-19) in China and Asia.

This paper provides a brief overview of the COVID-19. Based on the syndrome differentiation (辨證論治), the concept of clearing heat and detoxifying lung in traditional Chinese medicine is used to prevent and treat COVID-19 through restoring the vital qi (正氣) in human body and regulating the lung as well as spleen to strengthen the immune system. Traditional Chinese medicine has been used as a complementary therapy for the possible intervention of COVID-19 including traditional Chinese herbal decoctions, Chinese traditional patent medicines, acupuncture and moxibustion as well as the traditional health exercises in China and parts of Asia.

Traditional Chinese medicine plays a significant role in the prevention and treatment of COVID-19 pandemic. The infection cases of China are around 80,000 and a steady decline compared with the USA which has 5,000,000 infection cases and continuous increases. It is shown that more than 90% of patients recovered after the treatment of traditional Chinese herbal decoctions and Chinese traditional patent medicines without any side-effect compared to the use of Remdesivir (GS-5734). Acupuncture (針灸) and moxibustion (艾灸) stimulate the immune and nervous systems for preventing infectious diseases. Taichi (太極) and Baduanjin (八段錦) as the auxiliary aerobic exercise under the theory of Chinese medicine can enhance the immune system and improve the lung function. Thus, an integration of traditional Chinese Medicine and Western medicine is the best strategy for the prevention, treatment and control of COVID-19 pandemic in the future.

This paper describes traditional Chinese medicine as an effective way for the prevention and treatment of COVID-19.