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With the increasing demands of industrial applications, it is imperative for robots to accomplish good contact-interaction with dynamic environments. Hence, the purpose of this research is to propose an adaptive fractional-order admittance control scheme to realize a robot–environment contact with high accuracy, small overshoot and fast response.

Fractional calculus is introduced to reconstruct the classical admittance model in this control scheme, which can more accurately describe the complex physical relationship between position and force in the interaction process of the robot–environment. In this control scheme, the pre-PID controller and fuzzy controller are adopted to improve the system force tracking performance in highly dynamic unknown environments, and the fuzzy controller is used to improve the trajectory, transient and steady-state response by adjusting the pre-PID integration gain online. Furthermore, the stability and robustness of this control algorithm are theoretically and experimentally demonstrated.

The excellent force tracking performance of the proposed control algorithm is verified by constructing highly dynamic unstructured environments through simulations and experiments. In simulations and experiments, the proposed control algorithm shows satisfactory force tracking performance with the advantages of fast response speed, little overshoot and strong robustness.

The control scheme is practical and simple in the actual industrial and medical scenarios, which requires accurate force control by the robot.

A new fractional-order admittance controller is proposed and verified by experiments in this research, which achieves excellent force tracking performance in dynamic unknown environments.

In the past few decades, the content-based image retrieval (CBIR), which focuses on the exploration of image feature extraction methods, has been widely investigated. The term of feature extraction is used in two cases: application-based feature expression and mathematical approaches for dimensionality reduction. Feature expression is a technique of describing the image color, texture and shape information with feature descriptors; thus, obtaining effective image features expression is the key to extracting high-level semantic information. However, most of the previous studies regarding image feature extraction and expression methods in the CBIR have not performed systematic research. This paper aims to introduce the basic image low-level feature expression techniques for color, texture and shape features that have been developed in recent years.

First, this review outlines the development process and expounds the principle of various image feature extraction methods, such as color, texture and shape feature expression. Second, some of the most commonly used image low-level expression algorithms are implemented, and the benefits and drawbacks are summarized. Third, the effectiveness of the global and local features in image retrieval, including some classical models and their illustrations provided by part of our experiment, are analyzed. Fourth, the sparse representation and similarity measurement methods are introduced, and the retrieval performance of statistical methods is evaluated and compared.

The core of this survey is to review the state of the image low-level expression methods and study the pros and cons of each method, their applicable occasions and certain implementation measures. This review notes that image peculiarities of single-feature descriptions may lead to unsatisfactory image retrieval capabilities, which have significant singularity and considerable limitations and challenges in the CBIR.

A comprehensive review of the latest developments in image retrieval using low-level feature expression techniques is provided in this paper. This review not only introduces the major approaches for image low-level feature expression but also supplies a pertinent reference for those engaging in research regarding image feature extraction.

In a complex, ever-changing, and turbulent business world, encouraging employees to express their improvement-oriented novel ideas through voice behavior is crucial for organizations to survive and thrive. Understanding how to foster employee promotive voice at work is a significant issue for both researchers and managers. This study explores how to foster employee promotive voice through specific HRM practices and positive employee attitudes. It also examines the effect of employee promotive voice on perceived organizational performance.

This study employed a time-lagged multisource survey design. Data were collected from 215 executives, 790 supervisors, and 1,004 employees in 113 firms, and analyzed utilizing a multilevel moderated serial mediation model.

The findings of this study revealed that promotive voice was significantly related to perceived organizational performance. Innovation-enhancing HRM was positively associated with employee promotive voice. The HRM-voice relationship was partially mediated by employee job satisfaction. Power distance orientation was found to significantly moderate the relationship between innovation-enhancing HRM and employee job satisfaction at the firm level. Our findings showed that innovation-enhancing HRM policies may fail to foster promotive voice if they do not enhance employee job satisfaction.

This study challenges some taken-for-granted assumptions in the literature such as any high performance HRM bundles (e.g. HPWS) can foster employee promotive voice, and the effects of HRM are direct and even unconditional on organizational outcomes. It emphasizes the need to avoid potential unintended effects of HRM on employee voice and the importance of contextualizing voice research.

Although service researchers have long suggested that customer mistreatment adversely impacts service employees' outcomes, statistical integration of current empirical findings has been lacking. This meta-analysis aims to review and statistically synthesize the state of research on the relationship between customer mistreatment and service employees' affective, attitudinal and behavioral outcomes.

The authors included 221 effect sizes of 135 independent samples from 119 primary studies (N = 47,964). The authors used a meta-analytic approach to quantitatively review the relationship between customer mistreatment and service employees' affective, attitudinal and behavioral outcomes. Meta-analysis structural equation modeling was used to explore the mediation mechanism of service employees' affective outcomes on the relationships between customer mistreatment and employees' attitudinal and behavioral outcomes. Meta-regression was applied to explore the impact of contextual-level moderators (i.e. service provider type and service delivery mode) on these relationships. Furthermore, we compared the effects of customer mistreatment with the effects of other organizational-related factors on some commonly measured employee outcomes.

The results show that customer mistreatment has a significant negative impact on service employees' affective outcomes (i.e. negative emotions), attitudinal outcomes (i.e. job satisfaction, organizational commitment, work engagement and turnover intention) and behavioral outcomes (i.e. job performance, surface acting and emotional labor). Additionally, service employees' negative emotions mediate the association between customer mistreatment and employees' job satisfaction, turnover intention, surface acting and emotional labor. Furthermore, the relationships between customer mistreatment and service employees' negative emotions and job performance are influenced by a contextual-level moderator (i.e. service delivery mode).

The authors contribute to the literature by providing robust meta-analytic estimates of the effects of customer mistreatment on a variety of service employees' affective, attitudinal and behavioral outcomes, as well as the different magnitudes of the effect sizes between customer mistreatment and other job-related and personality-related factors by quantifying the true variability of the effect sizes. The authors draw on current theories underpinning customer mistreatment to test a theoretical model of the mediation mechanism of service employees' affective outcomes (i.e. service employees' negative emotions) on the relationships between customer mistreatment and employees' attitudinal and behavioral outcomes. The authors explore the effects of two contextual-level factors (i.e. service provider types and service delivery mode) related to the service delivery context that may account for the variability of effect sizes across empirical studies.

With the development of small towns in China, the country pays more and more attention to the protection of landscape resources. It is an urgent problem that is how to protect landscape resources and ecological environment while developing economic industry in small towns. Establishing an ecotourism evaluation model can provide valuable reference for ecotourism planning, development protection and sustainable development of small towns.

This paper uses the analytic hierarchy process (AHP) to construct the ecotourism evaluation system that accords with the characteristics of small towns. A judgment matrix is constructed to determine specific indicators and factor values based on expert survey results. Based on the AHP theory and considering 4 aspects, construction conditions of featured small towns, ecological and environmental conditions, ecotourism resources endowment and development conditions and tourism capacity. In addition, 16 factor evaluations were selected, evaluation model of ecotourism resources were built and each evaluation index value was confirmed by adopting expert's advice.

Ecological environment, socioeconomic, uniqueness, esthetic ornamental value, small-scale industry scale, type and development level, type and scale, tourism talent level, therapeutic and leisure value were the indispensable components of evaluation of ecotourism resources in featured small towns.

The ideas of ecological environment development are rooted in the hearts of the people with the development of times. The model in this research is pertinent, typical and universal to some extent. Thus it is worth popularizing and applying.

The purpose of this research is to explore the effect of proactivity on work–family enrichment through thriving at work and the moderation of such mediation by immediate supervisor perspective-taking.

Research data consisting of two-wave lagged data (N = 470) were collected from 470 employees of 17 domestic Chinese firms to examine the proposed moderated mediation model.

The findings show that proactivity was positively related to work–family enrichment and that thriving at work partially mediated this relationship. Immediate supervisor perspective-taking strengthens the effect of proactivity on thriving at work, and a positive indirect relationship exists between proactivity and work–family enrichment through thriving at work when immediate supervisor perspective-taking is high.

Organizations should formulate policies to motivate employees to engage in proactive behavior and stimulate employees' thriving at work. Organizations should also select leaders who are good at perspective-taking and provide training to leaders to help them take others' perspectives.

These results deepen our theoretical understanding of the consequences of proactivity by demonstrating the positive associations between proactive behavior and work–family enrichment. The current study also contributes to the literature by identifying the mediating mechanism of thriving at work to explain the relationship between proactivity and work–family enrichment. Furthermore, the results show that supervisor perspective-taking moderates the above mediation.

The purpose of this study is to examine the determinants of online community user participation from a social influence perspective.

Based on 450 valid responses collected from a survey questionnaire, structural equation modeling (SEM) technology was employed to examine the research model.

The results show that both social identity and group norm have significant effects on user participation. In addition, group norm affects social identity. It was not possible to find the effect of subjective norm on participation intention.

This research is limited to a particular sample: students. Thus the results need to be generalized to other samples, such as working professionals.

Extant research has mainly focused on the effects of user motivations such as perceived usefulness, trust and commitment on online community user behavior, and seldom considered the effects of social processes including compliance, identification and internalization on user behavior. This research tries to fill the gap.

The purpose of this paper is to examine a possible negative spillover effect in sports sponsorship to answer whether the sponsored team’s poor performance will have a negative effect on audiences’ trust in its sponsor’s brand. The authors further analysed whether the audience’s attitude towards the team plays a mediating role and whether the audience’s personality type (active vs passive) plays a moderating role in this negative spillover effect.

Three experimental studies were conducted with 380 Chinese undergraduates and MBA student participants over two years. The authors designed the experiment as a computer-mediated intervention in which good, poor and neutral performance groups were compared. After the respondents were exposed to the intervention, we asked them to answer questions using a computer terminal. We analysed the data from the three experiments through analysis of variance (ANOVA), regression analysis and a bootstrap.

The audiences who were exposed to a team’s poor performance condition reported less trust in the sponsor’s brand relative to those exposed to a good performance condition, and the brand trust was even lower than for those who were exposed to a control condition (no performance information). Further, the audience’s negative attitude towards the sports team mediated the negative effect of the team’s poor performance on its sponsor’s brand trust. The negative effect was more obvious for individuals with Type A personalities (active) than for those with Type B personalities (passive).

The prior literature has neglected a possible negative effect of a sports team’s performance on its sponsor’s brand trust. In particular, questions of whether, how and when this negative effect occurs are critical for sponsors, teams, and audiences. Since sports team sponsorship is burgeoning in China, the negative implications are unclear in this new context. Thus, the revelation that the negative spillover effects of a team’s poor performance on audiences’ trust in the sponsor’s brand provides two original contributions. First, the negative effect reveals value for multiple sponsorship stakeholders. Second, the Chinese context in this study adds value for future research and practice regarding both Chinese-foreign and domestic Chinese decisions.

The purpose of this research is to examine the effect of flow experience on mobile social networking service (SNS) users' loyalty.

Based on 305 valid responses collected from a survey questionnaire, structural equation modeling (SEM) technology was employed to examine the research model.

The results show that both information quality and system quality significantly affect users' trust and flow experiences, which further determine their loyalty. The results indicate that flow experience is the strongest determinant of users' loyalty.

Mobile SNS providers need to consider user experience when seeking users' loyalty. They should enhance information quality and system quality in order to improve user trust and flow experience.

Although much research has been conducted to explore the effects of extrinsic motivations, such as perceived usefulness, on mobile commerce user behavior, the effect of intrinsic motivations, such as flow experience, is seldom tested. This research found the effect of flow experience on mobile SNS users' loyalty to be significant.

The purpose of this paper is to examine the effect of network externality on users’ continuance of mobile social network sites (SNS).

Based on the 230 valid responses collected from a survey, structural equation modeling was employed to examine the research model.

The results indicated that network externality, which includes referent network size and perceived complementarity, has a significant effect on perceived usefulness and flow. Privacy concern affects perceived usefulness, flow and privacy risk. These three factors determine continued use.

Previous research has focussed on the effects of motivations such as perceived value on user adoption of SNS. The effect of network externality on user continuance has seldom been examined. This research tries to fill the gap.