Optimization of "vehicle-UAV" joint distribution routing for cold chain logistics considering risk of epidemic spreading and green cost.

To address the epidemic, such as COVID-19, the government may implement the home quarantine policy for the infected residents. The logistics company is required to control the risk of epidemic spreading while delivering goods to residents. In this case, the logistics company often uses vehicles and unmanned aerial vehicles (UAVs) for delivery. This paper studies the distribution issue of cold chain logistics by integrating UAV logistics with epidemic risk management innovatively. At first, a "vehicle-UAV" joint distribution mode including vehicles, small UAVs and large UAVs, is proposed. The green cost for vehicles and UAVs is calculated, respectively. The formula for infection risk due to large numbers of residents gathering at distribution centers to pick up goods is then derived. Furthermore, based on the control of infection risk, an optimization model is developed to minimize the total logistics cost. A modified ant colony algorithm is designed to solve the model. The numerical results show that the maximum acceptable risk and the crowd management level of distribution centers both have significant effects on the distribution network, logistics cost and number of new infections. Our study provides a new management method and technical idea for ensuring the needs of residents during the epidemic.

Effect of perceived organizational support on suicidal ideation of young employees: The mediator role of self-esteem.

This study aimed to explore the relationships among perceived organizational support, self-esteem, and suicidal ideation of young employees. A total of 447 unmarried employees completed the survey of perceived organizational support, Rosenberg self-esteem scale, and suicide ideation scale. The results revealed that perceived organizational support, self-esteem, and suicidal ideation were significantly correlated with each other. Stepwise regression analysis and path analysis both indicated that self-esteem partially mediated the effect of perceived organizational support on suicidal ideation.

The effect of psychological capital between work-family conflict and job burnout in Chinese university teachers: Testing for mediation and moderation.

In this study, we investigated the relationship between work-family conflict and job burnout as well as the potential mediation/moderation effects of psychological capital. Participants were 357 university teachers who completed a questionnaire packet containing a work-family conflict scale, psychological capital questionnaire, and Maslach Burnout Inventory-General survey. According to the results, work-family conflict and psychological capital were both significantly correlated with job burnout. In addition, psychological capital cannot mediate-but can moderate-the relationship between work-family conflict and job burnout. Taken together, our findings shed light on the psychological capital underlying the association of work-family conflict and job burnout.