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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.

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.

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 purpose of this paper is to demonstrate the impact of the welding sequence on the substrate plate distortion during the wire and arc additive manufacturing (WAAM) process. This paper also aims to show the capability of finite element simulations in the prediction of those thermally induced distortions.

An experiment was conducted in which solid aluminum blocks were manufactured using two different welding sequences. The distortion of the substrates was measured at predefined positions and converted into bending and torsion values. Subsequently, a weakly coupled thermo-mechanical finite element model was created using the Abaqus simulation software. The model was calibrated and validated with data gathered from the experiments.

The results of this paper showed that the welding sequence of a part significantly affects the formation of thermally induced distortions of the final part. The calibrated simulation model was able to capture the different distortion behavior attributed to the welding sequences.

Within this work, a simulation model was developed capable of predicting the distortion of WAAM parts in advance. The findings of this paper can be used to improve the design of WAAM welding sequences while avoiding high experimental efforts.

The paper provides a contribution of systematisation to the literature on the blue economy and aquaculture as challenging issues for achieving sustainable growth and a circular economy. The growing scientific interest in recent years and the increased attention in political agendas make the blue economy and aquaculture as promising fields for scientific investigation. The latter has been confirmed during a particular period too as the pandemic times. To identify those areas of specialisation emerging from the intersection of such topics, the paper embraces a systematic literature review for inspiring future research.

The study covers a period of 20 years by including 85 papers extracted from the Scopus database. Through the adoption of VOSviewer, the investigation explores the main descriptive statistics, while content analysis has been embraced to identify thematic areas.

The main results of this study are about statistics (i.e. publication trends, geographic distribution, most frequent keywords and most influential authors, etc.). Three main thematic areas have been identified in this study: SDGs and policies for sustainable development, food and energy, business models and managerial issues.

Practical implications arise both for firms and policymakers. About the firsts, interesting insights can be derived in terms of business model innovation, collaborative approaches and technological exploration. About policymakers, inspiration in terms of renewal of strategic guidelines, creation of enabling contextual conditions and evidences for new regulations can be noted.

Elements of original contributions can be identified in the adoption of an SLR to verify the advancement of the debate till the recent pandemic.