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This paper aims to use redundant manipulators to solve the challenge of collision avoidance in construction operations such as welding and painting.

In this paper, a null-space-based task-priority adjustment approach is developed to avoid collisions. The method establishes the relative position of the obstacle and the robot arm by defining the “link space,” and then the priority of the collision avoidance task and the end-effector task is adjusted according to the relative position by introducing the null space task conversion factors.

Numerical simulations demonstrate that the proposed method can realize collision-free maneuvers for redundant manipulators and guarantee the tracking precision of the end-effector task. The experimental results show that the method can avoid dynamic obstacles in redundant manipulator welding tasks.

A new formula for task priority adjustment for collision avoidance of redundant manipulators is proposed, and the original task tracking accuracy is guaranteed under the premise of safety.

The purpose of this study is to investigate a theoretical framework that examines and extends understanding of the role of cognitive/information processing, learning motivation and learning task behaviors in facilitating student engagement, course persistence and academic performance.

Student subjects were used to collect survey data. Hierarchical regression analysis was used to test the impact of active teaching, academic self-efficacy and task avoidance on the dependent variables – course grade, course persistence and expectancy for success.

Active teaching and academic self-efficacy were positive predictors of course grade while task avoidance was a negative predictor of course grade. Course persistence was positively impacted by academic self-efficacy and diminished by task-avoidance behaviors. Academic self-efficacy was shown to positively impact expectancy for success.

The results confirm the importance of adopting active teaching techniques, the need for periodic opportunities for experienced academic success and the need for coaching on self-regulation of study habits and class attendance behaviors.

This study builds on prior calls for more investigations on the role of teaching style on student psychological responses, engagement, learning task behaviors and academic performance. The teaching and learning processes were examined on four levels – attention/engagement, encoding, processing/synthesizing and learning task behaviors. In addition, prior work was extended by incorporating behavioral indicators (e.g. task avoidance) of learning motivation as opposed to reliance on self-reported levels of motivation that may have not been consistent with actual behaviors.

The paper aims to present a tracked robot comprised of several biochemical sampling instruments and a universal control architecture. In addition, a dynamic motion planning strategy and autonomous modules in sampling tasks are designed and illustrated at length.

Several sampling instruments with position tolerance and sealing property are specifically developed, and a robotic operation system (ROS)-based universal control architecture is established. Then, based on the system, two typical problems in sampling tasks, i.e. arm motion planning in unknown environment and autonomous modules, are discussed, implemented and tested. Inspired by the idea of Gaussian process classification (GPC) and Gaussian process (GP) information entropy, three-dimensional (3D) geometric modeling and arm obstacle avoidance strategy are implemented and proven successfully. Moreover, autonomous modules during sampling process are discussed and realized.

Smooth implementations of the two experiments justify the validity and extensibility of the robot control scheme. Furthermore, the former experiment proves the efficiency of arm obstacle avoidance strategy, while the later one demonstrates the time reduction and accuracy improvement in sampling tasks as the autonomous actions.

The proposed control architecture can be applied to more mobile and industrial robots for its feasible and extensible scheme, and the utility function in arm path planning strategy can also be utilized for other information-driven exploration tasks.

Several specific biochemical sampling instruments are presented in detail, while ROS and Moveit! are integrated into the system scheme, making the robot extensible, achievable and real-time. Based on the control scheme, an information-driven path planning algorithm and automation in sampling tasks are conceived and implemented.

The aim of the study was to examine whether five-star hotel employees’ promotion focus significantly influences their task-coping style, and whether their prevention focus has a significant effect on their emotion- and avoidance-coping styles. This study also investigates the moderating impact of employees’ tenure on the relationships between stress-coping styles and turnover intent.

A total of 342 five-star hotel employees in South Korea participated in the study using a self-administered questionnaire. Confirmatory factor analysis and structural equation modeling were used to examine the hypothesized relationships between the constructs.

Hotel employees’ turnover intent decreases when they are motivated by strategies corresponding to their regulatory focus. This study found that hotel employees’ promotion focus had a significant positive effect on their task-coping style, whereas prevention focus had a significant negative effect on the emotion- and avoidance-coping style. In addition, employees’ task-coping style negatively affected their intent to leave the organization, while their emotion-coping and avoidance-coping styles positively affected turnover intent. Finally, moderating effects were related to tenure in the causal relationships among stress-coping styles and turnover intent. Thus, one can infer that the emotion-coping style has a greater effect on turnover intent in employees with a relatively short tenure than in those with a long tenure.

This study verified that hotel employees’ regulatory focus plays an important role in employee behavior within organizations just as individual characteristics such as personality or values do. Thus, a substantial application plan for employees’ regulatory focus was proposed for the organizational dimension. In addition, diverse plans were presented for employees’ flexible coping with stress, based on differing turnover intent, depending on employees’ stress-coping styles. Through this, a plan for reducing employee turnover intent was pursued.

This study associated employees’ stress-coping styles, which had been dealt with in the human resources management area, with their regulatory focus and showed that different stress-coping styles might be derived using such regulatory focus; the resulting turnover intent might also be different. The study results can provide a theoretical basis for understanding relationships among regulatory focus, stress-copying styles and turnover intent as such research is relatively lacking. Finally, this study is meaningful in that it applied the regulatory focus theory centered on customer behaviors to employees and verified the moderating effect of employees’ tenure between stress-coping styles and turnover intent.

This study aims to investigate the effects of workplace bullying on the coping strategies (responses) and counterproductive behavior of hospitality employees.

The sample consisted of 284 luxury hotel employees in the Korean hospitality industry. SPSS and AMOS were the statistical programs used to verify the hypotheses of the present study. Confirmatory factor analysis and reliability analysis were conducted to verify the validity and reliability of the measured items. Before verification of the hypotheses, directivity between factors derived through correlation analysis was verified, and causal relationships with regard to the three hypotheses were verified through the structural equation model.

Organizational and work-related bullying had a significant effect on task coping, whereas personal bullying had a significant effect on emotional and avoidance coping. The results also showed that positive task coping did not significantly affect counterproductive behavior, but negative coping, such as emotional and avoidance responses, significantly affected employees’ counterproductive behavior.

The present study verified that coping responses in work situations can differ depending on the type of workplace bullying that occurs. Task coping, a positive coping strategy, was affected by organizational and work-related bullying, whereas emotional and avoidance coping, negative coping strategies, were negatively affected by personal bullying. Consequently, the possibility of harmful actions against organizations varies depending on the coping strategies chosen by employees who are exposed to bullying. Therefore, appropriate education should be offered to employees to use positive and proactive work-oriented coping strategies when dealing with bullying rather than negative methods such as emotional or avoidance coping.

Shifting to OLSL classes during the pandemic can bring learners ambivalent experiences: negative, positive or both appraisals toward the technologies. However, few studies have examined how ambivalent experiences can influence students' learning behaviors, specifically cyberslacking and active participation. Using the challenge-hindrance stressor framework, this study investigates the impact of challenge and hindrance appraisals on these learning behaviors.

This study uses a mixed methods approach to answer research questions. An interview was conducted to identify the key components of ambivalent appraisals, and a survey was conducted to empirically examine the impact of challenge and hindrance appraisals on learners' behaviors in online live streaming learning (OLSL) contexts. The data of 675 university students were analyzed using structural equation modeling.

This study found that hindrance appraisal leads to cyberslacking while challenge appraisal leads to active participation, but it can also cause cyberslacking. Social presence has a double-edged effect, acting as both a facilitator and inhibitor, strengthening the effect of hindrance appraisal on cyberslacking and the impact of challenge appraisal on active participation.

Prior studies have primarily focused on the negative side (techno-distress) of technology appraisals. This study simultaneously examines the positive side, techno-eustress, on learners' behaviors in OLSL contexts, and explores the moderating effects of social presence. This study contributes to the technostress and technology adaptation literature by revealing how technology-induced ambivalent appraisals impact behavioral responses. It offers important theoretical and practical implications for education tool designers.

The effects of stigmatisation regarding sex abuse and rape crimes have rarely been studied. This present study explores the effects of social stigma by examining coping style, thought suppression, depression and anxiety in those falsely accused of sex crimes compared with those convicted of sex crimes. A total of 60 males volunteered to complete a questionnaire. The questionnaires were given to participants from organisations that support people falsely accused and people who have been found guilty of sexual offending. The findings indicate that falsely accused individuals employ an emotion‐focused coping strategy significantly more than convicted sex offenders.

While presenteeism is empirically linked to lower productivity, the role of a person's motives for engaging in presenteeism has been overlooked. Using a Conservation of Resources Theory framework, we examine the moderating effects of presenteeism motives (approach and avoidance motives) on the presenteeism–productivity relationship.

A sample of 327 dental hygienists with chronic health conditions was surveyed. Moderated multiple regression was used to test study hypotheses.

Results indicate that presenteeism does indeed appear to detriment productivity. However, we demonstrate that motives are an important moderator, such that high approach motives appear to mitigate the negative effects of presenteeism on productivity.

Based on our findings, we suggest managers strive to improve the approach motives of their employees through processes such as job enrichment.

This study demonstrates that presenteeism is not always detrimental to productivity, as approach motives appear to mitigate the negative effects of presenteeism on productivity. These results could drive future research on presenteeism, as well as inform best practices related to managing workers with chronic health issues.

Most of the redundant dual-arm robots are singular free, dexterous and collision free compared to other robotic arms. This paper aims to analyse the workspace of redundant arms to study the manipulability. Furthermore, multi-layer perceptron (MLP) algorithm is used to determine the various joint parameters of both the upper body redundant arms. Trajectory planning of robotic arms is carried out with the help of inverse solutions obtained from the MLP algorithm.

In this paper, the kinematic equations are derived from screw theory approach and inverse kinematic solutions are determined using MLP algorithm. Levenberg–Marquardt (LM) and Bayesian regulation (BR) techniques are used as the backpropagation algorithms. The results from two backpropagation techniques are compared for determining the prediction accuracy. The inverse solutions obtained from the MLP algorithm are then used to optimize the cubic spline trajectories planned for avoiding collision between arms with the help of convex optimization technique. The dexterity of the redundant arms is analysed with the help of Cartesian workspace of arms.

Dexterity of redundant arms is analysed by studying the voids and singular spaces present inside the workspace of arms. MLP algorithms determine unique solutions with less computational effort using BR backpropagation. The inverse solutions obtained from MLP algorithm effectively optimize the cubic spline trajectory for the redundant dual arms using convex optimization technique.

Most of the MLP algorithms used for determining the inverse solutions are used with LM backpropagation technique. In this paper, BR technique is used as the backpropagation technique. BR technique converges fast with less computational time than LM method. The inverse solutions of arm joints for traversing optimized cubic spline trajectory using convex optimization technique are computed from the MLP algorithm.