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The advancement of enterprise social networks (ESNs) facilitates information sharing but also presents the challenge of managing information boundaries. This study aims to explore the factors that influence the information-control behavior of ESN users when continuously sharing information.

This study specifies the information-control behaviors in the “wall posts” channel and applies communication privacy management (CPM) theory to analyze the effects of the individual-specific factor (disposition to value information), context-specific factors (work-relatedness and information richness) and risk-benefit ratio (public benefit and public risk). Data on actual information-control behaviors extracted from ESN logs are examined using multilevel mixed-effects logistic regression analysis.

The study's findings show the direct effects of the individual-specific factor, context-specific factors and risk-benefit ratio, highlighting interactions between the individual motivation factor and ESN context factors.

This study reshapes the relationship of CPM theory boundary rules in the ESN context, extending information-control research and providing insights into ESNs' information-control practices.

To provide high torques needed to move a robot’s links, electric actuators are followed by a transmission system with a high transmission rate. For instance, gear ratios of 100:1 are often used in the joints of a robotic manipulator. This results into an actuator with large mechanical impedance (also known as nonback-drivable actuator). This in turn generates high contact forces when collision of the robotic mechanism occur and can cause humans’ injury. Another disadvantage of electric actuators is that they can exhibit overheating when constant torques have to be provided. Comparing to electric actuators, pneumatic actuators have promising properties for robotic applications, due to their low weight, simple mechanical design, low cost and good power-to-weight ratio. Electropneumatically actuated robots usually have better friction properties. Moreover, because of low mechanical impedance, pneumatic robots can provide moderate interaction forces which is important for robotic surgery and rehabilitation tasks. Pneumatic actuators are also well suited for exoskeleton robots. Actuation in exoskeletons should have a fast and accurate response. While electric motors come against high mechanical impedance and the risk of causing injuries, pneumatic actuators exhibit forces and torques which stay within moderate variation ranges. Besides, unlike direct current electric motors, pneumatic actuators have an improved weight-to-power ratio and avoid overheating problems.

The aim of this paper is to analyze a nonlinear optimal control method for electropneumatically actuated robots. A two-link robotic exoskeleton with electropneumatic actuators is considered as a case study. The associated nonlinear and multivariable state-space model is formulated and its differential flatness properties are proven. The dynamic model of the electropneumatic robot is linearized at each sampling instance with the use of first-order Taylor series expansion and through the computation of the associated Jacobian matrices. Within each sampling period, the time-varying linearization point is defined by the present value of the robot’s state vector and by the last sampled value of the control inputs vector. An H-infinity controller is designed for the linearized model of the robot aiming at solving the related optimal control problem under model uncertainties and external perturbations. An algebraic Riccati equation is solved at each time-step of the control method to obtain the stabilizing feedback gains of the H-infinity controller. Through Lyapunov stability analysis, it is proven that the robot’s control scheme satisfies the H-infinity tracking performance conditions which indicate the robustness properties of the control method. Moreover, global asymptotic stability is proven for the control loop. The method achieves fast convergence of the robot’s state variables to the associated reference trajectories, and despite strong nonlinearities in the robot’s dynamics, it keeps moderate the variations of the control inputs.

In this paper, a novel solution has been proposed for the nonlinear optimal control problem of robotic exoskeletons with electropneumatic actuators. As a case study, the dynamic model of a two-link lower-limb robotic exoskeleton with electropneumatic actuators has been considered. The dynamic model of this robotic system undergoes first approximate linearization at each iteration of the control algorithm around a temporary operating point. Within each sampling period, this linearization point is defined by the present value of the robot’s state vector and by the last sampled value of the control inputs vector. The linearization process relies on first-order Taylor series expansion and on the computation of the associated Jacobian matrices. The modeling error which is due to the truncation of higher-order terms from the Taylor series is considered to be a perturbation which is asymptotically compensated by the robustness of the control algorithm. To stabilize the dynamics of the electropneumatically actuated robot and to achieve precise tracking of reference setpoints, an H-infinity (optimal) feedback controller is designed. Actually, the proposed H-infinity controller for the model of the two-link electropneumatically actuated exoskeleton achieves the solution of the associated optimal control problem under model uncertainty and external disturbances. This controller implements a min-max differential game taking place between: (i) the control inputs which try to minimize a cost function which comprises a quadratic term of the state vector’s tracking error and (ii) the model uncertainty and perturbation inputs which try to maximize this cost function. To select the stabilizing feedback gains of this H-infinity controller, an algebraic Riccati equation is being repetitively solved at each time-step of the control method. The global stability properties of the H-infinity control scheme are proven through Lyapunov analysis.

Pneumatic actuators are characterized by high nonlinearities which are due to air compressibility, thermodynamics and valves behavior and thus pneumatic robots require elaborated nonlinear control schemes to ensure their fast and precise positioning. Among the control methods which have been applied to pneumatic robots, one can distinguish differential geometric approaches (Lie algebra-based control, differential flatness theory-based control, nonlinear model predictive control [NMPC], sliding-mode control, backstepping control and multiple models-based fuzzy control). Treating nonlinearities and fault tolerance issues in the control problem of robotic manipulators with electropneumatic actuators has been a nontrivial task.

The novelty of the proposed control method is outlined as follows: preceding results on the use of H-infinity control to nonlinear dynamical systems were limited to the case of affine-in-the-input systems with drift-only dynamics. These results considered that the control inputs gain matrix is not dependent on the values of the system’s state vector. Moreover, in these approaches the linearization was performed around points of the desirable trajectory, whereas in the present paper’s control method the linearization points are related with the value of the state vector at each sampling instance as well as with the last sampled value of the control inputs vector. The Riccati equation which has been proposed for computing the feedback gains of the controller is novel, so is the presented global stability proof through Lyapunov analysis. This paper’s scientific contribution is summarized as follows: (i) the presented nonlinear optimal control method has improved or equally satisfactory performance when compared against other nonlinear control schemes that one can consider for the dynamic model of robots with electropneumatic actuators (such as Lie algebra-based control, differential flatness theory-based control, nonlinear model-based predictive control, sliding-mode control and backstepping control), (ii) it achieves fast and accurate tracking of all reference setpoints, (iii) despite strong nonlinearities in the dynamic model of the robot, it keeps moderate the variations of the control inputs and (iv) unlike the aforementioned alternative control approaches, this paper’s method is the only one that achieves solution of the optimal control problem for electropneumatic robots.

The use of electropneumatic actuation in robots exhibits certain advantages. These can be the improved weight-to-power ratio, the lower mechanical impedance and the avoidance of overheating. At the same time, precise positioning and accurate execution of tasks by electropneumatic robots requires the application of elaborated nonlinear control methods. In this paper, a new nonlinear optimal control method has been developed for electropneumatically actuated robots and has been specifically applied to the dynamic model of a two-link robotic exoskeleton. The benefit from using this paper’s results in industrial and biomedical applications is apparent.

A comparison of the proposed nonlinear optimal (H-infinity) control method against other linear and nonlinear control schemes for electropneumatically actuated robots shows the following: (1) Unlike global linearization-based control approaches, such as Lie algebra-based control and differential flatness theory-based control, the optimal control approach does not rely on complicated transformations (diffeomorphisms) of the system’s state variables. Besides, the computed control inputs are applied directly on the initial nonlinear model of the electropneumatic robot and not on its linearized equivalent. The inverse transformations which are met in global linearization-based control are avoided and consequently one does not come against the related singularity problems. (2) Unlike model predictive control (MPC) and NMPC, the proposed control method is of proven global stability. It is known that MPC is a linear control approach that if applied to the nonlinear dynamics of the electropneumatic robot, the stability of the control loop will be lost. Besides, in NMPC the convergence of its iterative search for an optimum depends on initialization and parameter values selection and consequently the global stability of this control method cannot be always assured. (3) Unlike sliding-mode control and backstepping control, the proposed optimal control method does not require the state-space description of the system to be found in a specific form. About sliding-mode control, it is known that when the controlled system is not found in the input-output linearized form the definition of the sliding surface can be an intuitive procedure. About backstepping control, it is known that it cannot be directly applied to a dynamical system if the related state-space model is not found in the triangular (backstepping integral) form. (4) Unlike PID control, the proposed nonlinear optimal control method is of proven global stability, the selection of the controller’s parameters does not rely on a heuristic tuning procedure, and the stability of the control loop is assured in the case of changes of operating points. (5) Unlike multiple local models-based control, the nonlinear optimal control method uses only one linearization point and needs the solution of only one Riccati equation so as to compute the stabilizing feedback gains of the controller. Consequently, in terms of computation load the proposed control method for the electropneumatic actuator’s dynamics is much more efficient.

The purpose of this paper is to conceptualize job immobility concepts, e.g. staying in an unsatisfying job and perceiving limited opportunities to move and apply for another job. The existing literature on this situation of job immobility in which the employee is experiencing stuckness in the job is scattered across research domains, limited in scope and existing constructs are not clearly defined or operationalized.

In this conceptual paper, the authors propose the construct “locked at the job,” by reviewing and building on the job immobility literature and the theory of control and self-regulation.

This study defines the concept that consists of two dimensions as feeling dissatisfied in the current job and inactivity due to perceived limited job opportunities. This study proposes a conceptual model of antecedents and consequences of locked at the job, based on the person-environment fit theory.

This conceptual paper allows value to be added in practice by the conceptualization of locked at the job, in addition to providing a preview with respect to conceptual causes and consequences of this phenomenon.

Research on this job immobility phenomenon is scattered across different research domains, limited in scope and the concept has not been clearly defined or operationalized.

Given the growing interest in the topic of knowledge management (KM) in family firms (FFs) and the subsequent increasing number of papers published, this study aims to review the field to identify and analyze the main themes and trends.

This study applies bibliometric techniques to a sample of 146 papers published from 2007 to 2023 and their 8,126 unique cited references. Bibliometric coupling is performed on the sample papers to explore the current intellectual structure of the field of KM in FFs, whereas cocitations analysis is performed to investigate the different literature streams that served as roots for the development of such a field.

Bibliographic coupling reveals that sample papers can be grouped into four clusters, and, through papers content analysis, the author identifies their core themes as knowledge sharing, innovation, knowledge-based dynamic capabilities and intellectual capital. Cocitation analysis of the cited references revealed four main clusters that can be considered the literature streams that served as roots for the development of the field, i.e. knowledge-based view, socioemotional wealth, strategic management and social capital (as a theory and as a resource).

This study contributes to the literature on KM in FFs by extending prior systematic review efforts with bibliometric analyses and combining these results to highlight connections between the main research themes around which scholars have debated (i.e. the clusters identified through bibliometric coupling) and their theoretical foundations (i.e. the clusters identified through cocitation analysis). This study also has practical implications by synthesizing and informing managers about FFs’ advantages and weaknesses in the KM process.

Based on cognitive appraisal theory of stress, this study develops an integrated model to examine the double-edged sword effect and boundary conditions of the impact of organizational crisis on employee behavior.

This study collected 672 employees’ data through three stages of longitudinal follow-up. Hierarchical regression analysis and SPSS macro process were used to test the hypotheses.

The paper finds that organizational crisis induces unethical pro-organizational behavior through enhanced job insecurity and foster taking charge by stimulating career calling. Employee resilience negatively moderates the relationship between organizational crisis and job insecurity as well as the indirect effects of organizational crisis on unethical pro-organizational behavior through job insecurity. Conversely, it positively moderates the association between organizational crisis and career calling and the indirect effects on taking charge through career calling.

This study not only expands the research on the mechanisms of organizational crisis' effects on employees' behaviors but also provides practical guidance for corporate managers on how to respond to organizational crisis.

The following insights are available to organizations and managers: first, this study confirms that organizational crisis can be perceived as threatening stressors that create job insecurity, which in turn leads to pro-organizational unethical behavior. Therefore, managers in organizational crisis should focus on stress regulation and guidance, pay timely attention to changes in the mindset of employees to reduce job insecurity, and strictly prohibit unethical pro-organizational behavior. They should promptly calm and control the atmosphere of panic and anxiety in the organization, do a good job of coordinating the division of labor, reduce personnel conflicts and contradictions, create a good organizational climate and reduce employees' sense of stress and negative perceptions of organizational crisis, thus reducing job insecurity and being able to meet the challenges in a better state. Secondly, this study confirms that employees also perceive organizational crisis as challenges and develop career calling, which in turn inspires proactive change behaviors. This suggests that managers in organizational crisis should promote the positive perception of organizational crisis as challenge, stimulate the career calling of employees in organizational crisis and call on and encourage employees to actively adopt taking charge. Therefore, managers should promptly give employees work affirmation, rewards and punishments, enhance the sense of participation and intrinsic motivation of subordinates, improve self-efficacy and self-confidence levels, effectively reduce the negative perception of organizational crisis, awaken positive psychological energy within individuals, increase their sense of belonging to the organization and thus, increase employees' awareness of the positive challenges of organizational crisis, stimulate employees' career calling through positive and optimistic beneficial pressure drive them to lead the corresponding changes in the crisis. Finally, this study confirms that employees' own resilience can change the double-edged sword effect of organizational crisis. Employees with high resilience are more likely to see organizational crisis as challenge and are thus more likely to develop career calling and are more inclined to initiate change, while employees with low resilience are more likely to see organizational crisis as threat, are more negatively affected by them, develop greater job insecurity and are, thus, more inclined to commit unethical pro-organizational behaviors. This reflects the fact that organizations should constantly cultivate employees' resilience and enhance their cognitive toughness at the same time. For instance, the organization can regularly use promotional lectures and scenarios to help leaders and employees establish corporate ethics, strengthen moral beliefs and correctly understand the nature of unethical affinity behavior. Managers should encourage and advocate positive and correct behaviors such as overcoming difficulties, positive innovation and positive suggestions to promote the sustainable and healthy development of the organization.

The results of this study can increase the organization’s understanding of the negative effects of crisis, help the organization take measures to manage and guide the employees in organizational crisis, more effective and targeted functional changes within the organization, reduce stress damage and improve the efficiency and effectiveness of crisis management. It is also beneficial to improve competitiveness and foresight in the organization’s industry and enhance organizations and employees’ resilience.

This study explores the double-edged sword effect of organizational crisis on employees’ behavior from the perspective of the cognitive appraisal theory of stress, which theoretically opens up a new research perspective, enriches the research in the fields of organizational crisis and taking charge, pro-organizational unethical behavior relationship and practically provides theoretical guidance for enterprises and managers on how to effectively respond to organizational crisis from the employees, which is of great practical significance.

The purpose of this paper aims to design a robust wind turbine emulator (WTE) based on a three-phase induction motor (3PIM).

The 3PIM is driven by a soft voltage source inverter (VSI) controlled by a specific space vector modulation. By adjusting the appropriate vector sequence selection, the desired VSI output voltage allows a real wind turbine speed emulation in the laboratory, taking into account the wind profile, static and dynamic behaviors and parametric variations for theoretical and then experimental analysis. A Mexican hat profile and a sinusoidal profile are therefore used as the wind speed system input to highlight the electrical, mechanical and electromagnetic system response.

The simulation results, based on relative error data, show that the proposed reactive power control method effectively estimates the flux and the rotor time constant, thus ensuring an accurate trajectory tracking of the wind speed for the wind emulation application.

The proposed architecture achieves its results through the use of mathematical theory and WTE topology combine with an online adaptive estimator and Lyapunov stability adaptation control methods. These approaches are particularly relevant for low-cost or low-power alternative current (AC) motor drives in the field of renewable energy emulation. It has the advantage of eliminating the need for expensive and unreliable position transducers, thereby increasing the emulator drive life. A comparative analysis was also carried out to highlight the online adaptive estimator fast response time and accuracy.

To construct effective compliance programmes, the phenomenon of non-compliance and variations in its abidance must be elucidated. The purpose of this paper is to discuss the social reality of ethical decision making, which examines the internalisation of moral norms and realities of social behaviour and, therefore, the general non-compliance with everyday laws (Tyler, 2006).

This paper makes use of several social theories, including social proof theory, traditional social theory and social control theory. Humans are social beings, and decision-making in ethics is strongly influenced by herding behaviour (Roy, 2021). The behaviour of others and normative ethical standards inform the compliance of behaviour to an undiminishable degree.

Although there is a host of factors to consider, the success of compliance can largely be attributed to people’s perception and reception of authority. The perception of authority and legitimacy plays a vital role in appreciating the complexity of rule following. Legitimacy, and its embodiment by persons in public roles, is a cornerstone of the subsequent discussion.

This paper uncovers the underlying motivations of non-compliance as well as the social psychology involved in the ethics of compliance. Cross-disciplinary connections are made between the private and public sector and practical compliance recommendations. The significant impact of integrity culture and value-based compliance emerges from the dissection of the social reality.

This paper aims to investigate the relationship of female participation in labor force with the cybersecurity maturity of nations and the enabling role of e-government development in moderating the same.

The authors have conducted fixed-effects regression using archival data for 149 countries taken from secondary sources. Furthermore, the authors have grouped the sample countries into four levels of cybersecurity maturity (unprepared, reactive, anticipatory and innovative) using clustering techniques, and studied the influence of their interest variables for individual groups.

Results show that female participation in labor force positively influences national cybersecurity maturity, and e-government development positively moderates the said relationship, thereby enabling the empowerment of women.

Encouraging broader participation of women in the labor force and prioritizing investments in e-government development are essential steps that organizations and governments may take to enhance a country’s cybersecurity maturity level.

This study empirically demonstrates the impact of the nuanced interplay between female participation in labor force and the e-government development of a nation on its cybersecurity maturity.

This study aims to examine the relationship between knowledge management and career development in an era characterized by high levels of youth unemployment and a demand for specialized skills. Despite the increasing transition to a knowledge-based economy, there is a significant gap between young people’s skills and career readiness, necessitating an in-depth analysis of the role of knowledge management at the individual, organizational and national levels.

The authors conducted a qualitative study using the theory-context-characteristics-methodology approach based on a systematic literature review. The authors created an ecological framework for reflecting on knowledge management and career development, arguing for a multidisciplinary approach that invites collaboration across sectors to generate innovative and reliable solutions.

This study presents a comprehensive review of the existing literature and trends, noting the need for more focus on the interplay between knowledge management and career development. It emphasizes the need for businesses to promote the acquisition, storage, diffusion and application of knowledge and its circulation and exchange to create international business human capital.

The findings may help multinational corporations develop managerial training programs and recruitment strategies, given the demand for advanced knowledge-based skills in the modern workspace. The study also discusses the influences of education, experience and job skills on business managers’ performance, guiding the future recruitment of talents.

To the best of the authors’ knowledge, this review is among the first to assess the triadic relationship between knowledge management, career development and the global unemployment crisis. The proposed multidisciplinary approach seeks to break down existing silos, thus fostering a more comprehensive understanding of how to address these ongoing global concerns.

Existing tourism review articles have limited review topics and cover a relatively short period. This review paper aims to extend the coverage of the previous literature and enhances the completeness of tourism-related studies to provide comprehensive tourism-related literature from 1945 (World War II onward) to 2022. Specifically, this paper reveals the major research themes present in published tourism research during this time period and highlights the evolution of tourism research from the preliminary phase, the transversal phase, to the growth phase.

The present study visualizes tourism research through networks of coauthors and their countries and regions, cocitation analysis of keywords and explores the thematic evolution of tourism research after the World War II (i.e., 1945–2022) from Web of Science and Google Scholar through bibliometric analysis.

Findings reveal that the themes of tourism research in the past years can be divided into seven major research themes. The tourism research evolution from World War II to 2022 can be categorized into three stages: preliminary (1945–1970), transversal (1971–2004) and growth (2005–2022). In addition, the research themes of tourism are not static but evolve according to the dynamics of the society and the industry, and that seven main research themes have been formed, namely, “heritage tourism,” “medical tourism,” “adventure tourism,” “dark tourism,” “sustainable tourism,” “rural tourism” and “smart tourism.”

The present study expands and refines the comprehensive literature in tourism research, as well as reveals the trends and dynamics in tourism research through network analysis and thematic evolution research methods.

现有的旅游评论文章在审查主题方面有限, 并且涵盖的时间相对较短。本综述文章扩展了先前文献的涵盖范围, 增强了与旅游相关研究的完整性, 提供了从1945年（第二次世界大战之后）到2022年的全面旅游相关文献。具体而言, 本文揭示了此期间发表的旅游研究中的主要研究主题, 并突出了旅游研究从初步阶段、横向阶段到增长阶段的演变。

本研究通过共同作者及其国家的网络、关键词的共同引用分析, 将旅游研究可视化, 并探索二战后旅游研究的主题演变。本研究通过文献计量学分析, 将 Web of Science (WoS) 和 Google Scholar 中的旅游研究（即 1945–2022 年）可视化。

研究结果显示, 过去几年的旅游研究主题可分为七大研究主题。从第二次世界大战到 2022 年的旅游研究演变可分为三个阶段：初步阶段（1945–1970 年）、横向阶段（1971–2004 年）和成长阶段2005–2022 年）。此外, 旅游的研究主题并不是静态的, 而是根据社会和行业的动态而演变, 形成了七个主要研究主题, 即“遗产旅游”、“医疗旅游”、“冒险旅游”、“黑暗旅游”、“可持续旅游”、“乡村旅游”和“智慧旅游”。

本研究通过网络分析和主题演变研究方法扩展和完善了旅游研究方面的综合文献, 并揭示了旅游研究的趋势和动态。

Los artículos de revisión existentes sobre turismo tienen temas de revisión limitados y cubren un periodo relativamente corto. Este artículo de revisión amplía la cobertura de la bibliografía anterior y mejora la exhaustividad de los estudios relacionados con el turismo para ofrecer una bibliografía exhaustiva sobre el turismo desde 1945 (Segunda Guerra Mundial en adelante) hasta 2022. En concreto, este documento revela los principales temas de investigación presentes en la investigación turística publicada durante este periodo de tiempo y destaca la evolución de la investigación turística desde la fase preliminar, la fase transversal, hasta la fase de crecimiento.

El presente estudio visualiza la investigación turística a través de redes de coautores y sus países y regiones, análisis de co-citación de palabras clave, y explora la evolución temática de la investigación turística después de la Segunda Guerra Mundial (es decir, 1945–2022) a partir de Web of Science y Google Scholar mediante análisis bibliométricos.

Los resultados revelan que los temas de la investigación turística de los últimos años pueden dividirse en siete grandes temas de investigación. La evolución de la investigación turística desde la Segunda Guerra Mundial hasta 2022 puede clasificarse en tres etapas: preliminar (1945–1970), transversal (1971–2004) y de crecimiento (2005–2022). Además, los temas de investigación del turismo no son estáticos, sino que evolucionan según la dinámica de la sociedad y de la industria, y que se han formado siete temas principales de investigación, a saber: “turismo patrimonial”, “turismo médico”, “turismo de aventura”, “turismo oscuro”, “turismo sostenible”, “turismo rural” y “turismo inteligente”.

El presente estudio amplía y perfecciona la amplia bibliografía existente en el campo de la investigación turística, además de revelar las tendencias y la dinámica de la investigación turística mediante el análisis de redes y los métodos de investigación de evolución temática.