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An active disturbance rejection controller (ADRC) based on model compensation is proposed in this paper. The method should first be taken a nominal model of the robot to compensate. Subsequently, the uncertain external disturbance is estimated and compensated is used an expansion state observer (ESO) in real time, which can reduce the estimating range of observation for ESO. The purpose of this paper is to suggest a novel method to improve the system tracking performance, as well as the dynamic and static performance index.

A welding robot is a complicated system with uncertainty, time-varying, strong coupling and a nonlinear system; it is more complex as if it is used in an underwater environment, and it is difficult to establish an accurate dynamic model for an underwater welding robot. Aiming at the tracking control of an underwater welding robot, it is difficult to achieve the control performance requirements by the conventional proportional integral derivative method to realize automatic tracking of the seam.

The simulation experiment is carried out by MATLAB/Simulink, and the application experiment is recorded. The experimental results show that the control method is correct and effective, and the system’s tracking performance is stable, and the robustness and tracking accuracy of the system are also improved.

The seam gets plumper and smoother, with better continuity and no undercut phenomenon.

A welding robot is a complicated system with uncertainty, time-varying, strong coupling and non-linear system. It is more complicated if it is used in an underwater environment. It is difficult to establish an accurate dynamic model for an underwater welding robot. Aiming at the tracking control of an underwater welding robot, it is difficult to achieve the control performance requirements by the classical proportional integral derivative control method to realize automatic tracking of the seam. The purpose of this paper is to suggest a novel method to deal with these issues.

To combine the advantages of active disturbance rejection control (ADRC) and sliding mode control (SMC) to improve the shortcomings of a single control method, a hybrid control method for an underwater welding robot trajectory tracking based on SMC_ADRC is proposed in this research work.

The simulation experiment of the proposed approach is carried out by Matlab/Simulink, and the welding experiment is recorded. The seam gets plumper and smoother, with better continuity and no undercut phenomenon.

The proposed approach is effective and reliable, and the system’s tracking performance is stable, which can effectively reduce chattering and improve system robustness.

This study aims to develop a cross-level research model to explore the relationship between team-level contextual ambidexterity and employees' enterprise system (ES) ambidextrous use, and the mediating role of user empowerment in and moderating effect of leader–member exchange (LMX) on the relationship.

This study conducted a sequential mixed-methods approach, which included a quantitative survey and a qualitative case study. The survey, administered to 244 employees in 59 groups from a financial institution, analyzed the relationships between contextual ambidexterity and ES ambidextrous use. Furthermore, the cross-level mediation and moderation effects were explored. The case study, involving nine members in three groups from a manufacturing firm, served to reinforce the validity of the survey results.

Team-level contextual ambidexterity can affect ES ambidextrous use directly or through the partial mediator of user empowerment. Furthermore, this study highlights the moderating role of LMX in the relationship between contextual ambidexterity and user empowerment, thereby improving ES ambidextrous use.

This study contributes to the literature by uncovering the cross-level effect of contextual ambidexterity on ES ambidextrous use through user empowerment, thereby extending the ambidexterity perspective and self-determination theory to the ES context. Additionally, this study provides nuanced insights into how to enhance ES ambidextrous use by revealing the moderating role and moderated mediation effect of LMX anchoring on social exchange theory.

To gain a deeper understanding of the determinants impacting the intention of Chinese young consumers to utilize virtual try-on apps (VTOs), this study adopts a modified version of the electronic technology acceptance model (e-TAM). The primary objective is to investigate how consumers' characteristics influence their post-use feelings, subsequently affecting their attitude towards VTOs and their intention to use them. Additionally, this research aims to explore potential gender differences within this process.

In this study, a sample of 243 college students from a university in China was recruited to participate in on-site software use. A total of 227 valid questionnaires were collected and used for data analysis. Structural equation modeling (SEM) was employed to empirically evaluate the data and test the research hypotheses. Additionally, multiple group comparisons were conducted based on gender to examine potential differences in the acceptance process.

The findings of this study reveal a significant association between users' individual characteristics and post-use feelings. Moreover, there are notable differences between male and female students in terms of their perceptions of innovativeness, knowledge and understanding regarding post-use feelings. Notably, four variables within post-use feelings, except for perceived compatibility, are found to be predictive of attitude towards VTOs. Additionally, it is observed that attitude towards VTOs directly influences users' intention to utilize them.

This study contributes to the research on consumers' intention to use VTOs by examining the antecedents of post-use feelings, specifically four consumers’ individual characteristics. The findings of this study offer managerial insights for professionals to formulate marketing positioning and communication strategies.

Online hotel ratings, a form of electronic word of mouth (eWOM), are becoming increasingly important to tourism and hospitality management. Using sentiment analysis based on the big data technique, this paper aims to investigate the relationship between customer sentiment and online hotel ratings from the perspective of customers’ motives in the context of eWOM, and to further identify the moderating effects of review characteristics.

The authors first retrieve 273,457 customer-generated reviews from a well-known online travel agency in China using automated data crawlers. Next, they exploit two different sentiment analysis methods to obtain sentiment scores. Finally, empirical studies based on threshold regressions are conducted to establish the asymmetric relationship between customer sentiment and online hotel ratings.

The results suggest that the relationship between customer sentiment and online hotel ratings is asymmetric, and a negative sentiment score will exert a larger decline in online hotel ratings, compared to a positive sentiment score. Meanwhile, the reviewer level and reviews with pictures have moderating effects on the relationship between customer sentiment and online hotel ratings. Moreover, two different types of sentiment scores output by different sentiment analysis methods verify the results of this study.

The moderating effects of reviewer level and reviews with pictures offer new insights for hotel managers to make different customer service policies and for customers to select a hotel based on reviews from the online travel agency.

This paper contributes to the literature by applying big data analysis to the issues in hotel management. Based on the eWOM communication theories, this study extends previous study by providing an analysis framework for the relationship between customer sentiment and online hotel ratings from the perspective of customers’ motives in the context of eWOM.

Based on leadership and self-efficacy theories, this study investigates how team-level ambidextrous leadership influences employees' enterprise system (ES) use via their self-efficacy.

This study collected data from a cross-sectional survey including 218 employees working in 56 workgroups in a Chinese financial institution. The authors used a cross-level mediation analysis to test the research model.

The authors find that ambidextrous leadership influences employees' creative self-efficacy and performance self-efficacy and further improves employees' ES use. Moreover, creative self-efficacy mediates the relationship between ambidextrous leadership and explorative use, whereas performance self-efficacy mediates the relationship between ambidextrous leadership and both explorative and exploitative use.

This study first examines the relationships among ambidextrous leadership, self-efficacy and employees' ES use by developing a cross-level model. Furthermore, by considering ambidextrous leadership as an important team-level factor, this study extends a deeper understanding of ambidexterity theory of leadership in the ES context. In addition, our study extends self-efficacy theory by examining the mediating roles of the two types of self-efficacy (i.e. performance self-efficacy and creative self-efficacy) on ambidextrous leadership–ES use relationship.

Business intelligence (BI) has been applied in various domains to take better decisions and it provides different level of information to its stakeholders according to the information needs. The purpose of this paper is to present a literature review on recent works in BI. The two principal aims in this survey are to identify areas lacking in recent research, thereby offering potential opportunities for investigation.

To simplify the study on BI literature, it is segregated into seven categories according to the usage. Each category of work is analyzed using parameters such as purpose, domain, problem identified, solution applied, benefit and outcome.

The BI contribution in various domains, ongoing research in BI, the convergence of BI domains, problems and solutions, results of congregated domains, core problems and key solutions. It also outlines BI and its components composition, widely applied BI solutions such as algorithm-based, architecture-based and model-based solutions. Finally, it discusses BI implementation issues and outlines the security and privacy policies adopted in BI environment.

In this survey BI has been discussed in theoretical perspective whereas practical contribution has been given less attention.

A comprehensive survey on BI which identifies areas lacking in recent research and providing potential opportunities for investigation.

This study aims to investigate how firms of different sizes respond to competitive pressure from peers.

This study employs machine learning techniques to measure competitive pressure based on management discussion and analysis (MD&A) documents and then utilises the constructed pressure indicator to explore the relationship between competitive pressure and corporate risk-taking behaviours amongst firms of different sizes.

We find that firm sizes are positively associated with their risk-taking behaviours when firms respond to competitive pressure. Large firms are inclined to exhibit a high level of risk-taking behaviours, whereas small firms tend to make conservative decisions. Regional growth potential and institutional ownership moderate the relationships.

Utilising text mining techniques, this study constructs a novel quantitative indicator to measure competitive pressure perceived by focal firms and demonstrates the heterogeneous behaviour of firms of different sizes in response to competitive pressure from peers, advancing research on competitive market pressures.

The paper aims to provide an efficient meta-heuristic algorithm to solve the partial set covering problem (PSCP). With rich application scenarios, the PSCP is a fascinating and well-known non-deterministic polynomial (NP)-hard problem whose goal is to cover at least k elements with as few subsets as possible.

In this work, the authors present a novel variant of the ant colony optimization (ACO) algorithm, called Argentine ant system (AAS), to deal with the PSCP. The developed AAS is an integrated system of different populations that use the same pheromone to communicate. Moreover, an effective local search framework with the relaxed configuration checking (RCC) and the volatilization-fixed weight mechanism is proposed to improve the exploitation of the algorithm.

A detailed experimental evaluation of 75 instances reveals that the proposed algorithm outperforms the competitors in terms of the quality of the optimal solutions. Also, the performance of AAS gradually improves with the growing instance size, which shows the potential in handling complex practical scenarios. Finally, the designed components of AAS are experimentally proved to be beneficial to the whole framework. Finally, the key components in AAS have been demonstrated.

At present, there is no heuristic method to solve this problem. The authors present the first implementation of heuristic algorithm for solving PSCP and provide competitive solutions.

Multifilamentary Bi₂Sr₂CaCu₂O_x (Bi2212) superconductor composite wires are the only high-temperature superconducting round wires (RW) with sufficient critical current density (J_c) for superconducting magnets generating magnetic fields greater than 25 Tesla. Very complex microstructures of Bi2212 RWs including the voids or gas bubbles, filament to filament bridges and wire architecture strongly influence their electrical behavior. Especially, a large number of voids in Bi2212 superconducting filaments is believed to be the major current-limiting mechanism. However, the effect of the void structure on the Jc is not well understood yet.

In this paper, the authors first statistically analyzed the size and distribution of voids in filaments using the reported microscopic data, obtaining the essential statistical regularities. An electrical model was further developed to predict the J_c of multifilamentary wires while taking into account of the current limiting mechanisms of the void structure in filaments, and the current sharing roles of filament to filament bridges.

The model predicts the quantitative dependence of J_c on the number of Bi2212 filaments in each bundle of a double-restack wire and porosity. The results are useful optimizing design and fabrication of Bi2212 multifilamentary wires.

For the complex structure of voids and interfilamentary bridges inside Bi2212 multifilamentary superconducting wires, the authors took a statistical characterization and studied its effect on the critical current density Jc (the key index of evaluating the current carrying capacity).