Search Results (5)

Collaborative operation of heterogeneous UAV swarms in dense urban environments remains challenging because right-of-way allocation is often rigid, frequent replanning consumes considerable onboard computation, and paths obtained by purely mathematical optimization may not be easy to execute under real dynamic constraints. This paper presents a physics-informed, event-triggered path planning and control framework, termed Physics-Informed SSA-MPC. Its global search layer is built on the Sparrow Search Algorithm (SSA), whose search mechanism originates from sparrow foraging and anti-predatory behaviors. On this basis, the method combines an event-triggered Stackelberg game for airspace coordination, a physically constrained SSA for global path generation, and an event-triggered MPC for local replanning. Battery State of Health (SoH) is incorporated into the adaptive search process, while Lévy-flight updates are limited by the maximum available acceleration to avoid infeasible path mutations. Local replanning is activated only when predicted safety ellipsoids overlap or tracking errors exceed prescribed thresholds, which helps reduce redundant computation. Simulations in a digital twin of Lujiazui, Shanghai, show that the proposed method shortens path length by 3.3% to 14.9%, reduces obstacle-avoidance latency to 45 ms, and achieves a 100% engineering feasibility rate. Full article

The excessive occupation of ecological space (ES) due to city expansion and construction can reduce a variety of natural values and socioeconomic benefits, which would also bring challenges associated with ecological rights and justice between urban areas (with economic impetus) and rural areas (with rich ecological endowments). A more sustainable development mode is required to shift population–industry–land (PIL) allocation from urban-led commensalism (ULC) to PIL interaction by urban–rural mutualism (URM). Thus, an urban–rural integration six-step symbiotic framework (UISS) was built to reflect how the change in urban–rural integration symbiotic mode (the ULC to URM transformation process) can ameliorate socioeconomic inequity in ecological space (IES). Moreover, the two-way fixed-effects model and heterogeneity analysis are used to discuss how the improvement of urban–rural integration symbiotic development level (URI) ameliorates the IES under socioeconomic development to reduce the unfairness, differences between regions, and mismatch of gravity centers from the perspective of spatiotemporal and dynamic changes under various symbiotic environments. The comprehensive multi-perspective analysis of IES based on the symbiotic framework (MEU) was applied to reflect the effect of dynamic PIL interaction changes from ULC mode to URM mode on IES in Yunnan Province, China. The results can be obtained as follows: (1) The URI including symbiotic units of PIL shows a steady rise in growth, with a maximum growth rate of 22.89%, which indicates that the URI has changed from the urban-led commensalism development mode to the urban–rural mutualism development mode. (2) The IES in temporal unfairness has been steadily alleviated, but the spatial differences remain obvious due to the unique symbiotic environment. The dynamic changes in the distance of the gravity centers between ES and PO-IN reflect an increasing mismatch in some regions (e.g., Kunming), while decreasing in others (e.g., Qujing). (3) URI generates a significant symbiotic effect on IES to reduce unfairness, differences, and mismatch, especially through the integration of industrial and population symbiotic units. The heterogeneity analysis shows that a good symbiotic environment, including business environment, industrial structure, transportation conditions, and government size, is conducive to ameliorating IES through the environmental adaptability of symbiotic units. All the results can provide a scientific reference for regional sustainable planning and management under mutualistic population–industry–land interaction between urban and rural areas. Full article

This study considers ways in which workers can be allocated dynamically in the few hours before the truck departure to flush the system of orders that are almost completed, thereby increasing the service performance of the system. To implement a worker allocation policy correctly, we need to answer the following questions: how many workers should we move, and when? We present the optimal number of workers required and the switching time for the proposed three dynamic worker reallocation policies through simulation experiments. The number of workers required was determined by the difference between the current and target probability of success of an order in the system based on the state-dependent sojourn time distribution, and the performance of the system was measured by Next Scheduled Departure (NSD). We find that the policies with late switching times and higher target probability of success have a greater effect on customer satisfaction. Our results suggest that it is possible to improve service performance significantly, in some conditions, by moving the right number of workers to the right place at the right time. Full article

Lateral ankle sprains are one of the most frequent athletic injuries in football, causing deficits in balance. Motor Imagery (MI) has been successively included in sports rehabilitation as a complementary therapeutic intervention. The aim of the present study was to explore the effects of MI on static and dynamic balance and on the fear of re-injury in professional football players with Grade II ankle sprains. Fifty-eight participants were randomly allocated into two groups: First—MI group (n = 29) and second—Placebo group (n = 29), and they each received six intervention sessions. The first MI group received MI guidance in addition to the balance training program, while the second Placebo group received only relaxation guidance. One-way ANOVA showed statistically significant results for all variables, both before and 4 weeks after the interventions for both groups. The t-test showed statistically significant differences between the two groups for static balance for the right lower extremity (t = 3.25, S (two-tailed) = 0.002, p < 0.05) and also for heart rate (final value) in all time phases. Further research is needed in order to establish MI interventions in sports trauma recovery using stronger MI treatments in combination with psychophysiological factors associated with sports rehabilitation. Full article

Bus priority is an effective way to improve traffic efficiency and sustainability. To achieve this, the Bus Priority Lane (BPL) is adopted to provide exclusive right-of-way for buses. However, the BPL is underutilized if the frequency of buses is low. To address this issue, many studies focus on improving the BPL’s utilization efficiency by intermittently allowing general vehicles to access it. However, these studies still have some shortcomings: (i) bus priority cannot be guaranteed if general vehicles run on the BPL; and (ii) the traffic system lacks resilience, especially when the traffic demand is unbalanced. This paper proposes a dynamic right-of-way allocation for the BPL, considering traffic system resilience. On the one hand, it ensures absolute bus priority by controlling Connected Automated Vehicles (CAVs), so as they do not interfere with buses. On the other hand, it can improve traffic system resilience by allocating right-of-way for CAVs with heavy turning-movement demand. To test the effectiveness, the proposed control strategy is compared with the non-control baseline. The experiments are conducted under seven unbalanced-traffic-demand levels, four congestion levels, and five CAV Penetration Rates. The results show that the proposed strategy can ensure absolute bus priority and improve traffic efficiency and traffic system resilience. Full article