Search Results (57)

Collegiate student-athletes are particularly vulnerable to food insecurity (FI). Prevalence rates range from 9.9% to 65%, although research is limited among this population. Background/Objectives: The challenge of balancing academic and degree progression requirements with training and competition demands can increase the risk for FI among student-athletes. Furthermore, insufficient funds for food has been reported for student-athletes living both on campus and off campus. Methods: This qualitative study employed a phenomenological design and constructivist theoretical framework to explore the experiences of athletic trainers, sports dietitians/nutritionists, and other professionals working with student-athletes in identifying and addressing FI among student-athletes via a series of online focus groups. Results: Participants (n = 27, 12 public colleges) had ≥7 years of collegiate athletics work experience, and most had been in their current position for <3 years. Five approaches to FI screening emerged; specifically, no screening, screening varies by team/sport, informal screening, dietitian screening, and formal screening. Emerging social determinants of FI included financial challenges, competing priorities, cultural/societal impacts, limited life skills, and the food environment. All these factors precipitated on a systems level, including individual, team/athletic department, and university/societal tiers. Conclusions: Athletic department and university policies and budgetary decisions emerged as potential antagonists of food security among student-athletes. FI mitigation strategies for student-athletes must go beyond simply addressing individual factors. Obtainment of food security among collegiate student-athletes requires system changes at the team/athletic department and university tiers. Full article

Returning to work after extended holidays poses significant challenges to employees’ psychological adjustment, yet this phenomenon remains underexplored in organizational research. Drawing on the Conservation of Resources (COR) theory, this study develops and tests a moderated mediation model to examine how pre-holiday work-related irritation influences post-holiday workplace vigor through heightened need for recovery, and how perceived organizational support buffers this process. Data were collected through a four-wave time-lagged design surrounding the Chinese Spring Festival, with a final sample of 349 employees across diverse industries. Results show that pre-holiday emotional strain increases employees’ recovery needs, which in turn undermines their workplace vigor. Moreover, boundary strength at home and perceived organizational support buffer the indirect negative pathway, highlighting the critical roles of both personal and organizational resources in the recovery process. By shifting attention from burnout to positive energy states such as vigor, this study advances theoretical understanding of post-holiday adjustment dynamics and offers practical insights for organizations seeking to foster employee resilience and sustained engagement after structured breaks. Full article

The individual marathon optimal pacing sparring the runner to hit the “wall” after 2 h of running remain unclear. In the current study we examined to what extent Deep neural Network contributes to identify the individual optimal pacing training a Variational Auto Encoder (VAE) with a small dataset of nine runners. This last one has been constructed from an original one that contains the values of multiple physiological variables for 10 different runners during a marathon. We plot the Lyapunov exponent/Time graph on these variables for each runner showing that the marathon wall could be anticipated. The pacing strategy that this innovative technique sheds light on is to predict and delay the moment when the runner empties his reserves and ’hits the wall’ while considering the individual physical capabilities of each athlete. Our data suggest that given that a further increase of marathon runner using a cardio-GPS could benefit of their pacing run for optimizing their performance if AI would be used for learning how to self-pace his marathon race for avoiding hitting the wall. Full article

The rise of ride-hailing services has brought new riding experiences for passengers and exerted a profound impact on the traditional taxi market. To enhance patrol efficiency, increase revenue, and promote sustainable development in the taxi industry, traditional taxis have actively undergone transformation and adopted an integrated “online-offline” operating model, combining online order acceptance with offline order-taking. Meanwhile, a considerable number of orders are canceled by passengers after being accepted, leading to a waste of platform capacity, reduced order dispatch efficiency, and additional empty-running costs for drivers. This issue is particularly prominent during peak hours with order overflow. Based on the changes in taxi order acceptance during order overflow, this paper constructs a model for passenger order cancellation probability during peak hours, examines the relationship between regional order density and the proportion of offline taxi order acceptance, discusses the impact of regional order density changes on the passenger order cancellation probability and stakeholder returns, and proposes optimal order dispatch strategies for ride-hailing platforms with different order densities. Additionally, it analyzes more optimal taxi operating models under varying arrival states. The research findings provide more scientific and efficient operational recommendations for ride-hailing platforms and taxis, promoting sustainable development in the entire travel market and thereby contributing to a greener and more efficient travel environment. Full article

Coal is a major source of fuel in many countries, but its mining and use increase the impacts on human and environmental health. Given the wide variation in coal use by nation, we focused on one—the United States. Specifically, we examined the public health, community, and demographic characteristics of 130 U.S. counties with underground and/or surface coal mines that exemplify a land use that leads to a combination of natural and anthropogenic risks. We compared these 130 to other U.S. counties, finding that the coal counties had poorer health outcomes and behaviors, fewer community assets, lower socioeconomic status, and higher population losses compared to the remaining counties in their host states and other U.S. counties. Next, we looked for differences within the 130 coal counties. Counties with the most coal mines and production had the worst outcomes, especially when located in rural areas. We then examined federal programs to assist these coal communities, observing that the largest federal government programs appear to be sending more resources to the most distressed coal counties compared to the less distressed ones. The daunting challenge for the most heavily coal-dependent counties, their state governments, and federal government supporters is to jointly develop plans that are realistic and affordable, take advantage of local natural and human resources, and offer a path to sustainable existence. If the efforts do not succeed, these places run the risk of becoming politically invisible and their populations are likely to empty out. Full article

Calculating greenhouse gas (GHG) emissions across the supply chain presents a significant challenge for the pharmaceutical industry in achieving environmental sustainability. This article develops a comprehensive methodology for the data collection and calculation of GHG emissions in pharmaceutical distribution, with a focus on road transport and warehousing. The methodology specifies key data requirements and sources, enhancing transparency and alignment with industry standards, such as the GLEC Framework. Real-world pharmaceutical data were collected from a global logistics company operating in Southern Africa. The methodology was applied, which yielded significantly variable results. The calculated emission intensity factors differ significantly from those in the literature. Emissions from road transport ranged from 239.57 to 6156.80 gCO₂e/t-km, depending on the vehicle size, load factor, and empty running. Warehousing emissions results show a smaller variance, ranging from 6.07 to 8.85 kgCO₂e/m³ or 81.70 to 104.42 kgCO₂e/t. The insights from this article support the logistics company and other stakeholders in understanding their emissions and data requirements for enhanced assessments to advance sustainable practices in pharmaceutical logistics. Full article

As supply chains evolve toward the adoption of the Industrial Internet of Things (IIoT), vast amounts of data are collected by different systems across the manufacturing, logistics and transportation value chain. John G Russell (Transport) is a UK-based company involved in multiple lines of business in the supply chain. As the company adopts the utilization of data intelligence as a way to collect, process and utilize data for insights, this presents an opportunity for applying artificial intelligence (AI) approaches such as reinforcement learning (RL), to identify trends, and offer recommendations for improving the sustainability and efficiency of its logistics. Preliminary results show that we can achieve up to a 20–30% reduction in carbon emissions from the fleet of a segment of the transport business lines of the Russell Group. This paper presents a holistic framework for achieving sustainable supply chains, reducing costs as well as achieving operational efficiency using a supply chain digital twin. Full article

For applications such as home surveillance systems and assisted living for elderly care, sensing capabilities are essential for tasks such as locating, determining the approximate position of a person, or identifying the status of a person (static or moving), since the effects caused by the presence of people can be captured in the power received by signals in an infrastructure deployed for these purposes. Human interference in Received Signal Strength Indicator (RSSI) measurements between different pairs of wireless nodes can vary depending on whether the target is moving or static. To test these ideas, an experiment was conducted using four nodes equipped with the ZigBee protocol in each corner of an empty 6.9 m × 8.1 m × 3.05 m room. These nodes were configured as routers, communicating with a coordinator outside the room that instructed the nodes to send back their pairwise RSSI measurements. The coordinator was connected to a computer in order to log the measurements, as well as the time at which the measurements were generated. The code was run for every iteration of the experiment, whether the target was static, moving, or when the number of targets was increased to five. The data were then statistically analyzed to extract patterns and other target relational parameters. There was a correlation between the change in the pairwise RSSI and the path described by the target when moving through the room. The data presented by the results can aid algorithms for device-free localization and crowd classification, with a low infrastructure cost for both, and shed light on the relevant characteristics correlated with the path and crowd size in indoor settings. Full article

The aim of this work was to perform a simulation analysis of the dynamics of a freight wagon with a variant vibration damping: dry friction and viscous damping. The following mathematical models of the damping characteristics are presented: the Maxwell model and the Kolsch model. The differences among the types of damping were first analyzed based on the dynamic responses of the 1 DOF model. Simulation studies were then carried out in a VI-Rail environment with the use of S-curved track models comprising short straight sections connecting the curves. The track models differed in the values of curve radii, cant, and length, which made it possible to run at different speeds. The multibody model of the vehicle represents a typical two-axle freight wagon. The dynamics of the wagon model were investigated for two states: empty and laden. Standard kinematic and dynamic values were compared in order to investigate if the nature of the damping has a significant impact on the dynamic properties of a freight wagon. The analysis of the simulation study showed that replacing dry friction damping with the viscous one can generally reduce forces acting on the wheel–rail contact, which, in turn, can be related to improving the running behavior of wagons while reducing the negative impact on the track. Full article

The performance of timber harvesting equipment is important for local operational planning and for making decisions on the way in which the forests should be opened up. However, there are many options used to extract timber, and there is a high variability in their performance. Forwarding is commonly used and became an attractive option for low-access forests. A controlled experiment was set up in this study to see how the configuration of the trails, characterized in terms of slope and surface condition, and the extraction direction (uphill or downhill) may affect the performance of forwarding operations. GNSS (Global Navigation Satellite System) data were collected at a rate of 5 s for five replications of moving empty downhill and uphill, respectively, on a dirt trail, measuring 250 m in length and having a slope of about 11%. The same experiment was run with the machine loaded at full capacity, then four replications with the machine loaded and unloaded moving downhill and uphill, respectively, were performed on a forest road resembling a rocky trail, which measured 390 in length and had a slope of about 4%. GNSS data were used to extract the moving speed for all the tested conditions with the aim to compute the cycle time, and the payload volume estimate was used to estimate efficiency, and productivity, depending on extraction distance in a range of 50 to 1000 m. For the first trail, statistical comparison tests indicated significant differences in the speed of uphill and downhill movement, for both empty and loaded conditions, whereas for the second trail, there were no significant differences in speed. In addition, on the second trail, the sustained speed was almost double. These were reflected sharply in the cycle time, efficiency, and productivity, depending on extraction distance and trail condition. These findings are important for decision making on local operational planning and forest opening up. Full article

The liquid dosing system consists of machines and a computer (PC). The machines and the computer are connected to each other and communicate via the RS485 interface. The software installed on a computer (PC) consists of two separate modules (applications)—“server” and “operator”. The server runs continuously and communicates to and from the machines. Through the operator module, the nomenclature of customers, liquids, and cards can be created and edited. The operator module makes it possible to perform various operations such as loading credit on a card, blocking and unblocking cards, editing customer or card data, and others. Various reports can be made, such as a report on the consumption of a given customer, a report on the use of the customer card, a report on the liquid consumed, etc. The goal of the system is to perform automated dosing of liquid at the customer’s request, without the involvement of another person (operator). The choice of liquid, the amount, and the payment of the choice made is fully automatic. Payment is only by card, as in case of an attempt to make a dosage and insufficient availability for payment, the dosage is not carried out. The customer is informed of a small credit on the card. The connection between the machine and the operator display is based on a query from the display. The operator’s job involves replacing empty bottles in the machine and monitoring and following up on system irregularities. Full article

Freight wagons in Europe have used Y25 bogies since the 1960s. Although very cost-effective, Y25 suffers from intrinsic limitations due to its architecture and running behaviour. This study introduces an innovative lightweight bogie, named 4L bogie, aimed at removing those limitations as well as improving running dynamics and track friendliness. This task was particularly challenging as the high ratio between laden and tare weight (up to 5:1) forced us to use a non-conventional suspension system and an innovative architecture of frame, reducing the mass by about 15% and the yaw moment of inertia by about 30% with respect to the Y25 bogie. Maintenance issues were addressed by reducing the number of components and easing overhaul, while the new design was validated from both the structural and the running dynamics point of view, assessing its interaction with the track in terms of stability, curving behaviour and the vertical response of the 4L bogie. Stability was improved by about 20% even in empty conditions and high conicity at the wheel/rail contact. Vertical dynamic force on a straight track, evaluated according to the Ride Force Count metric, and wear behaviour on sharp and mild curves were considerably reduced, leading to an improved track friendliness of the bogie. Full article

Container drayage involves the transportation of containers by trucks. Although the distance is relatively short compared to maritime and rail transport, container drayage accounts for 25% to 40% of the total container transportation costs and significantly contributes to increased fuel consumption and carbon emissions. Thus, the modeling of the container drayage problem (CDP) has received a lot of attention in the last two decades. However, the three fundamental modeling factors, including the combination of trucking operation modes and empty container relocation strategies, as well as empty container constraints and multiple inland depots, have not been simultaneously investigated. Hence, this study addressed a comprehensive CDP that simultaneously incorporates the three modeling factors. The problem was formulated as a novel mixed integer linear programming (MILP) model based on the DAOV graph. Given the complexity of this problem, it was not realistic to find an exact solution for large instances. Therefore, an improved genetic algorithm (GA) was designed by integrating the “sequential insertion” method and “solution re-optimization” operation. The performance of Gurobi and GA was validated and evaluated through randomly generated instances. The results indicate that (1) the proposed algorithm can provide near-optimal solutions for large-scale instances within a reasonable running time, (2) the greatest cost savings from combining trucking operation modes and empty container relocation strategies range from 10.45% to 31.86%, and (3) the three modeling factors significantly influence the fuel consumption and carbon emissions, which can provide managerial insights for sustainable container drayage practices. Full article

This paper presents investigations of rail vehicle bogies of the Y25 type. The Y25 bogie family is one of the most commonly used freight car bogie designs. In addition to several significant advantages characterising this design, several disadvantages have also been observed since the beginning of more than fifty years of its operation in several types of cargo vehicles. One of these defects observed in real systems is its “unsatisfactory running stability”, particularly for long straight tracks. This paper used the commercial engineering software VI-Rail (2010.13.0) to create a model of a gondola car (type 412W Eaos) with two Y25 bogies. The car model was tested in empty and loaded (maximum permissible load) modes. Its motion along straight and curved tracks with different radii values was analysed. The vehicle velocity was changed from a few m/s to the maximum values for which stable solutions of the model existed. For each route, the nonlinear critical velocity was determined, defining the maximum operating velocity of the modelled car. The model solutions were recorded, while just one was selected to present the results—the first wheelset’s lateral displacement y_lw. Conjecture about its “imperfect running quality” on curved tracks was confirmed. The possible appearance of self-exciting wheelset vibrations in the modelled car’s operating velocity range in a laden state was also observed. The research results on the impact of changes in the bogie suspension parameters on the vehicle model’s stability are presented. The crucial parameter in the bogie suspension was indicated. Reducing its value by several percent about the nominal value increases the critical velocity of the car to values higher than the maximum operating velocity of the modelled vehicle. Full article

The parameters of the roll characteristics of a large-scale round bale machine were collected in real time to investigate the bale rolling mechanism. This investigation develops a set of adaptable and highly integrated data acquisition systems for the bale rolling performance parameters of large-type round bale machines. A rolling experiment is conducted using sunflower straw as the material, and the power consumption and radial tension of the roller-round bale machine during the bale rolling process are studied. In the grass core formation stage, the round bale machine’s torque need was minimal, the radial tension of the bale remained nearly constant, and the bale chamber was primarily filled with loose sunflower straw. The motor torque and the straw bale’s radial tension both showed a tendency of gradual increase when the round bale machine was in the grass-filling stage. The motor torque and bale radial tension displayed a roughly linear trend of rapid rise as the sunflower straw continued to enter the rolling bale chamber; this was when the round bale machine was in the compressed bale rolling stage. When the power consumption of the round bale machine was measured using the data acquisition system during the test bench empty run and core-creation stage, the energy consumption comparison analysis produced a relative error of 5.8%. During the stage of bale rolling and compression, the data acquisition system monitored the power consumption of the round bale machine. The relative error was 9.5%. The data acquisition system of the round bale machine test bed has an accuracy of 90.5%–94.2% when measuring the machine’s power consumption, indicating that it is a stable and efficient system. This study provides a foundation for further research on intelligent the roller-round bale machine. Full article