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This paper aims to discuss the precise altitude and velocity tracking control of a hypersonic vehicle, a global adaptive neural backstepping controller was studied based on a disturbance observer (DOB).

The DOB combined with a radial basis function (RBF) neural network (NN) was used to estimate the disturbance terms that are generated by the flexible modes of the hypersonic vehicle system. A global adaptive neural method was introduced to approximate the unknown system dynamics, with robust control terms pulling the system transient states back into the neural approximation domain externally.

The globally uniformly ultimately bounded for all signals of a closed-loop system can be guaranteed by the proposed control algorithm. Additionally, the command filtered backstepping methods can avoid the explosion of the complexity problem caused by the backstepping design process. In addition, the effectiveness of the proposed controller can be verified by the simulation used in this study.

Normally lateral dynamics issue should be discussed in the process of control system designed, the lateral dynamics are not included in the nonlinear dynamic model of hypersonic vehicle used in this paper, merely the longitudinal flight dynamics are discussed in this paper.

The flexible states in rigid modes are considered as the disturbance of the system, which is estimated by structuring DOB with NN approximations. The compensating tracking error and prediction error are used in the update law of RBF NN weight. The differential explosions complexity derived from the backstepping procedure is dealt with by using command filters.

Focusing on the problem that the visual detection algorithm of navigation path line in intelligent harvester robot is susceptible to interference and low accuracy, a navigation path detection algorithm based on improved random sampling consensus is proposed.

First, inverse perspective mapping was applied to the original images of rice or wheat to restore the three-dimensional spatial geometric relationship between rice or wheat rows. Second, set the target region and enhance the image to highlight the difference between harvested and unharvested rice or wheat regions. Median filter is used to remove the intercrop gap interference and improve the anti-interference ability of rice or wheat image segmentation. The third step is to apply the method of maximum variance to thresholding the rice or wheat images in the operation area. The image is further segmented with the single-point region growth, and the harvesting boundary corner is detected to improve the accuracy of the harvesting boundary recognition. Finally, fitting the harvesting boundary corner point as the navigation path line improves the real-time performance of crop image processing.

The experimental results demonstrate that the improved random sampling consensus with an average success rate of 94.6% has higher reliability than the least square method, probabilistic Hough and traditional random sampling consensus detection. It can extract the navigation line of the intelligent combine robot in real time at an average speed of 57.1 ms/frame.

In the precision agriculture technology, the accurate identification of the navigation path of the intelligent combine robot is the key to realize accurate positioning. In the vision navigation system of harvester, the extraction of navigation line is its core and key, which determines the speed and precision of navigation.

People generally believe that business with negative word-of-mouth, such as negative customer reviews can hardly have good sales. But a number of intriguing examples seem to contradict such beliefs. Academic has so far begun to explore the possible positive effect of negative customer reviews, but without unfolding its underlying mechanism. This paper proposes a mechanism through which the variance of customer reviews moderates the effect of negative reviews on sales.

This study takes a multi-method approach in explaining the phenomenon, including an empirical analysis using secondary data from a movie review website and a movie box office website and a subsequent experimental study in a controlled experiment.

The findings of the study show that the effect of negative customer reviews on product sales is positive when the variance of customer reviews is large. Moreover, customers’ motivation to learn fully mediates the moderating effect of review variance on valence.

The findings provide vital managerial implications and suggest that managers should realize the important role of the review distribution.

This study mainly contributes to research on the negativity bias by identifying an important unexplored moderator and mediator and thus explains why negative customer review increases movie sales.

This paper aims to propose cooperative control strategies for dual-arm robots in different human–robot collaborative tasks in assembly processes. The authors set three different regions where robot performs different collaborative ways: “teleoperate” region, “co-carry” region and “assembly” region. Human holds the “master” arm of dual-arm robot to operate the other “follower” arm by our proposed controller in “teleoperation” region. Limited by the human arm length, “follower” arm is teleoperated by human to carry the distant object. In the “co-carry” region, “master” arm and “follower” arm cooperatively carry the object to the region close to the human. In “assembly” region, “follower” arm is used for fixing the object and “master” arm coupled with human is used for assembly.

A human moving target estimated method is proposed for decreasing efforts for human to move “master” arm, radial basis functions neural networks are used to compensate for uncertainties in dynamics of both arms. Force feedback is designed in “master” arm controller for human to perceive the movement of “follower” arm. Experimental results on Baxter robot platform show the effectiveness of this proposed method.

Experimental results on Baxter robot platform show the effectiveness of our proposed methods. Different human-robot collaborative tasks in assembly processes are performed successfully under our cooperative control strategies for dual-arm robots.

In this paper, cooperative control strategies for dual-arm robots have been proposed in different human–robot collaborative tasks in assembly processes. Three different regions where robot performs different collaborative ways are set: “teleoperation” region, “co-carry” region and “assembly” region.

The purpose of this study is to present a holistic literature review on crime research in the hospitality and tourism field.

This literature review included 109 crime-related academic papers in seven primary sources, namely, ScienceDirect, EBSCOhost’s hospitality and tourism complete, Emerald Management eJournals, Sage Journals, Google Scholar, Scopus and Web of Science.

From the exploration and synthesis of 109 articles, the following categories of crime research in the hospitality and tourism field emerged as follows: classification of crime research in the hospitality and tourism field; diversity of tourists, crime and risk perceptions; the impacts of crime on the hospitality and tourism industry; and crime control from stakeholders’ papers. In addition, this study advances crime research by proposing six research priorities for future investigation.

Tourism stakeholders are advised to achieve better cooperation in crime control under the guidance of the crime prevention model. High-technology tools are encouraged to be applied to detect and track criminal activities. Meanwhile, diverse applications of the media should be used as useful tools to control criminal activities in the hospitality and tourism industry.

This paper fills a gap by presenting the first comprehensive overview of crime research in the hospitality and tourism field in the past few decades and proposing six priorities for this research stream.

This study reveals the trigger of innovative behavior from the perspective of intrinsic and extrinsic spiritual inspiration and provides a new research idea for the formation mechanism of innovative behavior. The purpose of this study is to provide certain guidance and implications for enterprises to cultivate and enhance employees’ innovative behavior.

We conducted three studies, collected multi-source data (N = 1,175) from different countries longitudinally, as well as used hierarchical regression analysis and fuzzy-set quantitative comparative analysis to verify the theoretical model.

According to the findings, both spiritual leadership and career calling have a positive impact on employees’ innovative behavior through the mediating effect of autonomous motivation and the moderating effect of person-vocation fit.

Innovative behavior is the positive professional pursuit of employees, which is difficult to form without the motivation of spiritual factors. Spirituality is a complex concept that contains intrinsic and extrinsic spiritual factors, both of which could stimulate employees’ innovative behavior. Although many discussions have been held on this topic in recent years, little attention has been paid simultaneously to the motivating effects of the two perspectives. Drawn from self-determination theory, this study explores the mechanisms of two spiritual motivation paths (i.e. the intrinsic and extrinsic spiritual motivation paths) in the improvement of employees’ innovative behavior.

This study aims to investigate the impact of the development of high-speed rail (HSR) network on earnings management, especially on the trade-off between the usage of accruals-based earnings management (AM) and real earnings management (RM) techniques, and consequently, examines the extent to which the HSR network–earnings management nexus is moderated by governance and religion factors.

Using a sample of Chinese A-listed firms over an 11-year period, this study uses regression techniques as the baseline methodology while controlling for industry and year-fixed effects. The authors also use endogeneity tests (including instrumental variable method, Generalized Methods of Moments estimation and difference-in-difference) and different robustness checks.

The key findings are threefold. First, the HSR network development reduces AM. This suggests that the presence of HSR network is effective in reducing information asymmetry. Second, the use of RM technique increases with the HSR network development. This indicates that managers do not seem to engage in less earnings management with the HSR network development but instead appear to switch from the easy-to-detect AM to the more costly RM approach. Finally, the HSR network and earnings management nexus is moderated by governance and religion factors.

This study provides new evidence on the trade-off between AM and RM by managers and pioneers in examining the impacts of governance and religion factors on the relationship between the HSR network and the trade-off of earnings management techniques.

This paper aims to investigate the primary motivations for China’s outward foreign direct investment (ODI) decisions.

Using a panel data sample covering the period 2003–2012 and a comprehensive set of 176 host countries.

This study finds that market size, trade variables and natural resource variables are strongly related to the Chinese ODI stocks. This indicates that Chinese ODI decisions are driven by both market- and resource-seeking motives. The subperiod sample test results lend even stronger support to the market-seeking motive for ODI.

These results seem to emerge from the policy changes that were undertaken during the sample period. Consistent with subgroup tests, this study finds that the main purposes of China’s ODI in the top 100 countries are natural resource explorations and production line replacements.

The purpose of this paper is to investigate the effects of corporate dispersion on tax avoidance from geographical and institutional dispersion perspectives by using evidence from China.

Using a panel data of Chinese listed firms during 2003-2015, this paper estimates with correlation analysis and multiple regression analysis.

Both geographical and institutional dispersion are negatively associated with the degree of corporate tax avoidance. Furthermore, corporate governance mechanisms and female chief executive officers can mitigate the negative relation between corporate dispersion and tax avoidance. The results also indicate that ineffective internal control is one of the channels through which corporate dispersion reduces tax avoidance.

This is the first paper about the impact of firm dispersion on the degree of tax avoidance, complementing the research content of diversification and corporate decision-making.

The purpose of this paper is to explore how logo design characteristics influence consumer response based on visual representation. Logos in different areas may have different characteristics that impact liking a logo. The logos of youth education brands were explored in this study.

The Kansei engineering (KE) method was employed in this research. In total, 115 logos of youth education brands were collected and classified into three categories: abstract, natural and text mark. Then 12 of these logos were selected as representative samples. A set of 171 Kansei pairwise image words was collected, and 14 of them were chosen for further investigation. The psychological projection experiment was conducted based on a five-point Likert-scale questionnaire with 120 participants. Three statistical methods including cluster analysis, factor analysis and correlation analysis were combined for the data analysis.

The results show that four factors affect liking a logo including a sense of contemporaneity, a sense of esthetics, a feeling of interest and a sense of style. Accordingly, the weights of these four factors are proposed. The positive correlation between logo characteristics and liking a logo was also verified. In addition, the classification results of this study confirm the wide use of natural and English text mark logos in youth education brands.

The results could guide designers and managers in selecting or modifying logo design for achieving a positive effective response. This is the first research on logo design characteristics linked with industry domains. This study also contributes to the KE approach to investigate the relative impact of logo characteristics on liking a logo.