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Component positioning is an important part of aircraft assembly, aiming at the problem that it is difficult to accurately fall into the corresponding ball socket for the ball head connected with aircraft component. This study aims to propose a ball head adaptive positioning method based on impedance control.

First, a target impedance model for ball head positioning is constructed, and a reference positioning trajectory is generated online based on the contact force between the ball head and the ball socket. Second, the target impedance parameters were optimized based on the artificial fish swarm algorithm. Third, to improve the robustness of the impedance controller in unknown environments, a controller is designed based on model reference adaptive control (MRAC) theory and an adaptive impedance control model is built in the Simulink environment. Finally, a series of ball head positioning experiments are carried out.

During the positioning of the ball head, the contact force between the ball head and the ball socket is maintained at a low level. After the positioning, the horizontal contact force between the ball head and the socket is less than 2 N. When the position of the contact environment has the same change during ball head positioning, the contact force between the ball head and the ball socket under standard impedance control will increase to 44 N, while the contact force of the ball head and the ball socket under adaptive impedance control will only increase to 19 N.

In this paper, impedance control is used to decouple the force-position relationship of the ball head during positioning, which makes the entire process of ball head positioning complete under low stress conditions. At the same time, by constructing an adaptive impedance controller based on MRAC, the robustness of the positioning system under changes in the contact environment position is greatly improved.

Prefabricated technology is gradually being applied to the construction of subway stations due to its characteristic of mechanization. However, the prefabricated subway station in China is in the initial stage of development, which is prone to construction safety issues. This study aims to evaluate the construction safety risks of prefabricated subway stations in China and formulate corresponding countermeasures to ensure construction safety.

A construction safety risk evaluation index system for the prefabricated subway station was established through literature research and the Delphi method. Furthermore, based on the structure entropy weight method, matter-element theory and evidence theory, a hybrid evaluation model is developed to evaluate the construction safety risks of prefabricated subway stations. The basic probability assignment (BPA) function is obtained using the matter-element theory, the index weight is calculated using the structure entropy weight method to modify the BPA function and the risk evaluation level is determined using the evidence theory. Finally, the reliability and applicability of the evaluation model are verified with a case study of a prefabricated subway station project in China.

The results indicate that the level of construction safety risks in the prefabricated subway station project is relatively low. Man risk, machine risk and method risk are the key factors affecting the overall risk of the project. The evaluation results of the first-level indexes are discussed, and targeted countermeasures are proposed. Therefore, management personnel can deeply understand the construction safety risks of prefabricated subway stations.

This research fills the research gap in the field of construction safety risk assessment of prefabricated subway stations. The methods for construction safety risk assessment are summarized to establish a reliable hybrid evaluation model, laying the foundation for future research. Moreover, the construction safety risk evaluation index system for prefabricated subway stations is proposed, which can be adopted to guide construction safety management.

The aim of this study is to examine the agency problems that arise between retail property owners and outsourced facility management (FM) service vendors in Ghana.

This study was carried out using telephone and face-to-face interviews. Nine facility managers (n =9) and six retail property owners (n = 6) purposively selected participated in the interviews. The responses from the interviews were analysed using content analysis. To begin with the analysis, the recorded audio for each respondent during the interviews was transcribed to augment what was written during the interviews. The next step was the development of a coding framework where each of the agency problems was assigned unique codes and grouped under themes. Each response was assigned a predefined code based on the agency problems identified in the literature. The research team discussed the consistency of the thematic codes assigned to each of the responses to ensure that each response was captured under the appropriate agency problem theme it best represents.

The results showed that agency problems in FM outsourcing in the Ghanaian retail sector are related to disagreement on expenditure associated with maintenance and repairs and improper tenant information sharing and use by FM service providers. Based on the findings, it is recommended that property owners explore the mixed approach to FM to mitigate the risks of complete outsourcing of FM services. It is also recommended that a clear path on how tenant information can be shared be pre-agreed in FM contracts.

This study provides new literature relating to agency problems in outsourcing and may be the first of its kind for FM in the Ghanaian retail industry. The findings could serve as a starting point for service providers and their principals to find common grounds to understand each other and mitigate the agency problems that could arise and their overall impact on performance.

Microribbon with meander type based on giant magnetoimpedance (GMI) effect has become a research hot spot due to their higher sensitivity and spatial resolution. The purpose of this paper is to further optimize the line spacing to improve the performance of meanders for sensor application.

The model of GMI effect of microribbon with meander type is established. The effect of line spacing (Ls) on GMI behavior in meanders is analyzed systematically.

Comparison of theory and experiment indicates that decreasing the line spacing increases the negative mutual inductance and a consequent increase in the GMI effect. The maximum value of the GMI ratio increases from 69% to 91.8% (simulation results) and 16.9% to 51.4% (experimental results) when the line spacing is reduced from 400 to 50 µm. The contribution of line spacing versus line width to the GMI ratio of microribbon with meander type was contrasted. This behavior of the GMI ratio is dominated by the overall negative contribution of the mutual inductance.

This paper explores the effect of line spacing on the GMI ratio of meander type by comparing the simulation results with the experimental results. The superior line spacing is found in the identical sensing area. The findings will contribute to the design of high-performance micropatterned ribbon with meander-type GMI sensors and the establishment of a ribbon-based magnetic-sensitive biosensing system.

Designing an effective metaverse experience through a tourism digital-twin platform is crucial to the success of metaverse tourism. How such a digital-twin platform should appeal to target users, however, lacks exploration. The study aims to advance a conceptual contribution by successfully creating a metaverse experience through a well-designed digital-twin platform. It also aims to show how the design science approach in tourism can enrich our understanding of digital-twin platform design elements introduced in metaverse experience design.

Guided by the design science approach in tourism, this research conceptualizes the role of digital-twin elements in metaverse experience design and proposes a one-factor between-subject experimental design to examine the effect.

This research conceptualizes how eight unique configurations of digital-twin design, which are embellished in two or three dimensions, shape tourists’ metaverse experience and physical travel intention.

The results offer operators clear strategic guidance on designing an effective tourism digital-twin platform.

This study not only identifies the impact of digital-twin platform design elements but also clarifies how such elements affect customers’ metaverse experiences.

通过旅游数字孪生平台设计有效的元宇宙旅游体验, 对元宇宙旅游的成功至关重要。然而, 这样一个旅游数字孪生平台应该如何吸引目标用户,还缺乏探索。该研究旨在通过精心设计的数字孪生平台成功塑造旅游者的元宇宙体验, 从而在概念上做出贡献。它还旨在展示旅游设计科学方法如何丰富我们对元宇宙体验设计中引入的数字孪生平台设计要素的理解。

在旅游设计科学方法的指导下, 本研究将概念化数字孪生平台设计元素在元宇宙体验设计中的作用, 并提出了一个单因素的受试者间实验设计来检验效果。

本研究将数字孪生平台设计的九种独特配置概念化, 这些配置在三个维度上得到了点缀, 塑造了游客的元宇宙旅游体验和现实旅游意向。

研究结果为产业者设计有效的旅游数字孪生平台提供了明确的战略指导。

现有的研究是第一个研究数字孪生平台设计元素的影响, 阐明了这些元素如何影响旅游者的元宇宙体验。

Diseñar una experiencia efectiva en el metaverso a través de una plataforma digital gemela de turismo es crucial para el éxito del turismo en el metaverso. Sin embargo, la exploración de cómo debería atraer dicha plataforma digital gemela a los usuarios objetivo carece de exploración. El estudio tiene como objetivo avanzar en una contribución conceptual al crear con éxito una experiencia en el metaverso a través de una plataforma digital gemela bien diseñada. También tiene como objetivo mostrar cómo el enfoque de la ciencia del diseño en el turismo puede enriquecer nuestra comprensión de los elementos de diseño de la plataforma digital gemela introducidos en el diseño de experiencias en el metaverso.

Guiada por el enfoque de la ciencia del diseño en el turismo, esta investigación conceptualiza el papel de los elementos gemelos digitales en el diseño de experiencias metaversales y propone un diseño experimental de un factor entre sujetos para examinar su efecto.

Esta investigación conceptualiza cómo ocho configuraciones únicas de diseño gemelo-digital, enriquecidas en dos o tres dimensiones, conforman la experiencia metaversal de los turistas y su intención de viaje físico.

Los resultados ofrecen a los operadores una orientación estratégica clara para diseñar una plataforma gemelo-digital turística eficaz.

Este estudio no sólo identifica el impacto de los elementos de diseño de las plataformas gemelas digitales, sino que también aclara cómo afectan dichos elementos a las experiencias metaversales de los clientes.

This study aims to examine newcomers experiencing maladjustment due to cognitive diversity, specifically, how maladjustment affects their turnover intentions; the mediating role of reported workplace bullying; and the buffering effect of perceived inclusive practices in the hospitality sector.

The authors collected time-lagged data from 403 respondents and analyzed the data through hierarchical regression analyses using statistical package for the social sciences (SPSS) 25.0.

Role ambiguity, low self-efficacy and social exclusion could each lead to newcomers’ reported workplace bullying (NRB). Perceived inclusive practices buffered the impacts of role ambiguity and social exclusion. NRB negatively mediated the relationships between role ambiguity and NRB; and social exclusion and NRB.

Hospitality practitioners should specify work procedures to minimize role ambiguities and record service processes to correct mistakes, reward veterans who help newcomers improve self-efficacy, invite newcomers to develop inclusive practices and review employee comments on third-party platforms to understand factors responsible for turnover intention.

This study contextualized cognitive diversity into newcomers’ maladjustment-bullying-turnover model in China’s hospitality industry. It highlighted the buffering effect of perceived inclusive practices in the relationships between maladjustment and reported bullying and turnover intentions among newcomers and confirmed the important role of self-efficacy in addressing adverse work events.

The emergence of virtual reality (VR) has the potential to revolutionize various industries, including tourism, as it delivers a simulated environment that closely emulates real-life experiences. Therefore, this study aims to explore how the factors, i.e. enjoyment, emotional involvement, flow state, perceived privacy risk, physical risk and cost, influence the customers’ intention to use VR for tourism.

This study integrates the technology acceptance model, hedonic consumption theory with other factors, including cognitive response, authenticity, perceived privacy risk, perceived physical risk, perceived cost and perceived presence. Partial least squares structural equation modelling approach was used to test the proposed research model.

The finding based on the sample of 252 respondents revealed that authenticity is the most influential factor impacting behavior intention followed by perceived cost, attitude, cognitive response and enjoyment. Also, the study supported the moderating impact of personal innovativeness between attitude and behavioral intention to use VR for tourism.

The findings of the study offers practical implications for service providers, site managers, destination marketers, tourist organizations and policymaker to develop more effective strategies for offering VR services for tourism.

This study enriches the current understanding of VR adoption in context of tourism with empirical evidences.

This paper aims to propose a novel control scheme and offer a control parameter optimizer to achieve better automatic carrier landing. Carrier landing is a challenging work because of the severe sea conditions, high demand for accuracy and non-linearity and maneuvering coupling of the aircraft. Consequently, the automatic carrier landing system raises the need for a control scheme that combines high robustness, rapidity and accuracy. In addition, to exploit the capability of the proposed control scheme and alleviate the difficulty of manual parameter tuning, a control parameter optimizer is constructed.

A novel reference model is constructed by considering the desired state and the actual state as constrained generalized relative motion, which works as a virtual terminal spring-damper system. An improved particle swarm optimization algorithm with dynamic boundary adjustment and Pareto set analysis is introduced to optimize the control parameters.

The control parameter optimizer makes it efficient and effective to obtain well-tuned control parameters. Furthermore, the proposed control scheme with the optimized parameters can achieve safe carrier landings under various severe sea conditions.

The proposed control scheme shows stronger robustness, accuracy and rapidity than sliding-mode control and Proportion-integration-differentiation (PID). Also, the small number and efficiency of control parameters make this paper realize the first simultaneous optimization of all control parameters in the field of flight control.

This study aims to explore the dissemination and evolutionary path of online public opinion from a crisis management perspective. By clarifying the influencing factors and dynamic mechanisms of online public opinion dissemination, this study provides insights into attenuating the negative impact of online public opinion and creating a favorable ecological space for online public opinion.

This research employs bibliometric analysis and CiteSpace software to analyze 302 Chinese articles published from 2006 to 2023 in the China National Knowledge Infrastructure (CNKI) database and 276 English articles published from 1994 to 2023 in the Web of Science core set database. Through literature keyword clustering, co-citation analysis and burst terms analysis, this paper summarizes the core scientific research institutions, scholars, hot topics and evolutionary paths of online public opinion crisis management research from both Chinese and international academic communities.

The results show that the study of online public opinion crisis management in China and internationally is centered on the life cycle theory, which integrates knowledge from information, computer and system sciences. Although there are differences in political interaction and stage evolution, the overall evolutionary path is similar, and it develops dynamically in the “benign conflict” between the expansion of the research perspective and the gradual refinement of research granularity.

This study summarizes the research results of online public opinion crisis management from China and the international academic community and identifies current research hotspots and theoretical evolution paths. Future research can focus on deepening the basic theories of public opinion crisis management under the influence of frontier technologies, exploring the subjectivity and emotionality of web users using fine algorithms and promoting the international development of network public opinion crisis management theory through transnational comparison and international cooperation.

The study aims to examine how different types of green brand ritual (GBR) influence customer engagement behavior and the mediation mechanisms and boundary conditions of the positive and negative pathways.

The study conducts two online experiments to collect data from a total of 940 consumers in China. Hypotheses are tested by independent samples t-test, two-way ANOVA and Hayes' PROCESS model.

Different kinds of GBR have different effects on customer engagement behavior. Internal GBR is more likely to play a positive role by inciting connectedness to nature. External GBR is more likely to play a negative role by inciting psychological resistance. This dual effect is especially pronounced for warm brands rather than competent brands.

The study pioneers the brand ritual into the field of interactive marketing and enriches its dual effect research. Additionally, the study figures out whether the category of brand ritual can trigger negative effect.

Inappropriate brand rituals are worse than no rituals at all. The results provide guidance for green companies to design effective brand rituals to strengthen the connection with consumers. Green brands should describe brand rituals in vivid detail and consciously lead consumers to immerse themselves in them.