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The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

Devices for step estimation are body-worn devices used to compute steps taken and/or distance covered by the user. Even though textiles or clothing are foremost to come to mind in terms of articles meant to be worn, their prominence among devices and systems meant for cadence is overshadowed by electronic products such as accelerometers, wristbands and smart phones. Athletes and sports enthusiasts using knee sleeves should be able to track their performances and monitor workout progress without the need to carry other devices with no direct sport utility, such as wristbands and wearable accelerometers. The purpose of this study thus is to contribute to the broad area of wearable devices for cadence application by developing a cheap but effective and efficient stride measurement system based on a knee sleeve.

A textile strain sensor is designed by weft knitting silver-plated nylon yarn together with nylon DTY and covered elastic yarn using a 1 × 1 rib structure. The area occupied by the silver-plated yarn within the structure served as the strain sensor. It worked such that, upon being subjected to stress, the electrical resistance of the sensor increases and in turn, is restored when the stress is removed. The strip with the sensor is knitted separately and subsequently sewn to the knee sleeve. The knee sleeve is then connected to a custom-made signal acquisition and processing system. A volunteer was employed for a wearer trial.

Experimental results establish that the number of strides taken by the wearer can easily be correlated to the knee flexion and extension cycles of the wearer. The number of peaks computed by the signal acquisition and processing system is therefore counted to represent stride per minute. Therefore, the sensor is able to effectively count the number of strides taken by the user per minute. The coefficient of variation of over-ground test results yielded 0.03%, and stair climbing also obtained 0.14%, an indication of very high sensor repeatability.

The study was conducted using limited number of volunteers for the wearer trials.

By embedding textile piezoresistive sensors in some specific garments and or accessories, physical activity such as gait and its related data can be effectively measured.

To the best of our knowledge, this is the first application of piezoresistive sensing in the knee sleeve for stride estimation. Also, this study establishes that it is possible to attach (sew) already-knit textile strain sensors to apparel to effectuate smart functionality.

The study aims to optimize truck routes by minimizing social and economic costs. It introduces a strategy involving diverse drones and their potential for reusing at DNs based on flight range. In HTDRP-DC, trucks can select and transport various drones to LDs to reduce deprivation time. This study estimates the nonlinear deprivation cost function using a linear two-piece-wise function, leading to MILP formulations. A heuristic-based Benders Decomposition approach is implemented to address medium and large instances. Valid inequalities and a heuristic method enhance convergence boundaries, ensuring an efficient solution methodology.

Research has yet to address critical factors in disaster logistics: minimizing the social and economic costs simultaneously and using drones in relief distribution; deprivation as a social cost measures the human suffering from a shortage of relief supplies. The proposed hybrid truck-drone routing problem minimizing deprivation cost (HTDRP-DC) involves distributing relief supplies to dispersed demand nodes with undamaged (LDs) or damaged (DNs) access roads, utilizing multiple trucks and diverse drones. A Benders Decomposition approach is enhanced by accelerating techniques.

Incorporating deprivation and economic costs results in selecting optimal routes, effectively reducing the time required to assist affected areas. Additionally, employing various drone types and their reuse in damaged nodes reduces deprivation time and associated deprivation costs. The study employs valid inequalities and the heuristic method to solve the master problem, substantially reducing computational time and iterations compared to GAMS and classical Benders Decomposition Algorithm. The proposed heuristic-based Benders Decomposition approach is applied to a disaster in Tehran, demonstrating efficient solutions for the HTDRP-DC regarding computational time and convergence rate.

Current research introduces an HTDRP-DC problem that addresses minimizing deprivation costs considering the vehicle’s arrival time as the deprivation time, offering a unique solution to optimize route selection in relief distribution. Furthermore, integrating heuristic methods and valid inequalities into the Benders Decomposition approach enhances its effectiveness in solving complex routing challenges in disaster scenarios.

To effectively combat the increasing rates of obesity, it is crucial to explore how environmental factors like sidewalk access impact weight-related outcomes. This study aimed to systematically examine the association between sidewalk accessibility and weight-related outcomes.

Databases were searched by keywords for relevant articles, which were published before March 3, 2024, to report the role of neighborhood sidewalk access on weight-related outcomes. The main findings of the selected articles were extracted from eligible studies by two independent reviewers.

A total of 20 out of 33 studies indicated a significant negative relationship between access to sidewalks and weight-related outcomes. Three studies demonstrated an indirect relationship between access to sidewalks and weight-related outcomes by greater access to physical environments. In addition, five studies reported no clear relationship, and three studies reported a significantly positive relationship between access to sidewalks and weight-related outcomes.

In general, people who live in urban areas with better sidewalk access benefit from better weight-related outcomes. Adults showed this correlation more prominently than adolescents and children. Therefore, sidewalks that have a positive effect on physical activity levels could be considered as a preventive measure against obesity.

One of the weight-related outcomes is obesity. Every community faces numerous challenges due to obesity, which adversely affects the quality of life and health. Environmental factors such as access to sidewalks could be associated with body weight due to lifestyle influences.

Data from different countries suggest a higher prevalence of anxiety, depression and suicides among manual and trade workers in the construction industry than in the general population. The present review examines the causes and effects of poor mental health and the effectiveness of interventions to improve manual and trade workers' mental health in the construction industry. It also identifies gaps in research and makes several suggestions for practice and future research.

A systematic literature review was conducted to examine and consolidate evidence reported in 54 relevant journal articles published between 2010 and 2021 on the mental health of manual and trade workers.

Three major themes emerged in the review of the 54 journal articles: causes of poor mental health, effects of poor mental health and interventions to improve mental health. The leading causes of poor mental health among construction manual and trade workers are poor work-life balance, high job demand, poor cultural norms and mental health stigma, chronic bodily pain, lack of social support, workplace injustice and job insecurity. The prominent effects of poor mental health are suicidality, drug and alcohol addiction, poor workplace safety and poor work performance. Moreover, the study found that some of the strategies recently implemented in the construction industry to improve mental health are deemed ineffective, or their effectiveness remains inconclusive.

The review's scope is limited to research on manual and trade workers, and it did not investigate the mental health of construction professionals and construction management students.

The review provides valuable insights into the causes and effects of poor mental health among manual and trade workers and the effectiveness of mental health interventions in the construction industry.

This paper aims to define the efficiency achieved by urban transport companies in Spain concerning the resources they use, considering the type of management used for implementation, public-private, and size.

This study consisted of an analysis of the efficiency of 229 public-private urban transport operators during the period 2012–2021 using Data Envelopment Analysis, the Malmquist Index and inference estimators to determine productivity, efficiency change into Pure Technical Efficiency Change (PTECH), and scale efficiency change.

Based on the efficiency analysis, the authors concluded that of the 229 companies studied, more than 35 were inefficient in all analysed periods. Considering the sample used, direct management is considered significantly more efficient. It cannot be concluded that the size of these companies influences their efficiency, as the data show unequal development behaviours in the studied years.

This study provides arguments on whether there is a significant difference between the two types of management in the urban transport sector. It also includes firm size as a study variable, which has not been previously considered in other studies related to urban transport efficiency. Efficiency should be a crucial factor in determining funding allocation in this sector, as it encourages operators to optimize and improve their services.

Village health volunteers are community health volunteers in Thailand that have helped the government deliver public health services for many years, particularly during the coronavirus disease 2019 (COVID-19) pandemic. Though labeled as “volunteers,” the village health volunteers are recruited, trained and supervised in a manner similar to how a government agency recruits, trains and supervises its street-level bureaucrats (SLBs). This study examines the two factors that affect how these street-level quasi-bureaucrats use their professional discretion: transformational leadership and public service motivation (PSM). Transformational leadership means a leadership style that develops, shares and sustains a vision to elevate SLBs to higher levels of performance, while PSM is defined as an SLB’s predisposition to make a difference by working in the public sector with a sense of calling. This study attempts to analyze the mediating role of psychological empowerment in the relationship between transformational leadership, PSM and professional discretion.

The paper uses a three-wave survey-based quantitative method to avoid common method biases. This method provides evidence gathered from 105 subdistrict health promotion hospitals and 798 village health volunteers (VHVs) in five provinces in Thailand.

PSM and transformational leadership influence the village health volunteers' use of professional discretion indirectly through the psychological empowerment mechanisms that make them feel positive toward their village health volunteer role and responsibility. The authors' findings suggest that the hospital directors' transformational leadership induces the village health volunteers' use of professional discretion by making them feel competent to do their work and feel fulfilled and valuable about their work. Similarly, the village health volunteers' PSM leads them to use professional discretion by making them feel fulfilled and valuable and by convincing them of the social and community impact of their work.

While existing research focuses on VHVs' role in alleviating capacity constraints on the health care system, this study revealed an equally important role played by hospital directors. These directors' transformational leadership was instrumental in enhancing VHVs' psychological empowerment – particularly their perceptions of the meaning of their work and their competence – that ultimately enabled them to use professional discretion in their work. This study also highlighted the importance of VHVs' PSM, which leads to their use of professional discretion via the meaning and impact dimensions of psychological empowerment. Based on this study, PSM should also be incorporated into the community health volunteers' recruitment criteria. Also, public health agencies should consider including transformational leadership in the hospital directors' training programs and their promotion criteria.

As VHVs' high-PSM level was found to enhance their professional discretion, the process of recruiting ordinary citizens to serve as community health volunteers should incorporate assessment of the candidates' PSM. Also, the Ministry of Public Health should design and assign tasks that citizen volunteers, particularly VHVs, consider meaningful and at which they feel competent.

Aside from technical training, directors of the subdistrict health promotion hospitals should regularly receive soft skill training (i.e. leadership training) and transformational leadership characteristics should be included in the government criteria for promotion.

While past research has examined the impact of other leadership styles on psychological empowerment, this study took a further step by examining the mediating effects of psychological empowerment on the relationship between transformational leadership and professional discretion among VHVs. The authors analyzed the mechanism linking PSM to the VHVs' professional discretion. In addition, by examining the relative importance of different dimensions of psychological empowerment, this study offers a nuanced understanding of the psychological processes by which transformational leadership and PSM shape the SLBs' use of professional discretion in their work.

This study investigates the relationships among digital transformation, technological innovation, industry–university–research collaborations and labor income share in manufacturing firms.

The relationships are tested using an empirical method, constructing regression models, by collecting 1,240 manufacturing firms and 9,029 items listed on the A-share market in China from 2013 to 2020.

The results indicate that digital transformation has a positive effect on manufacturing companies’ labor income share. Technological innovation can mediate the effect of digital transformation on labor income share. Industry–university–research cooperation can positively moderate the promotion effect of digital transformation on labor income share but cannot moderate the mediating effect of technological innovation. Heterogeneity analysis also found that firms without service-based transformation and nonstate-owned firms are better able to increase their labor income share through digital transformation.

This study provides a new path to increase the labor income share of enterprises to achieve common prosperity, which is important for manufacturing enterprises to better transform and upgrade to achieve high-quality development.

This study responded to the call to empirically reconcile conflicting findings in unethical pro-organizational behavior (UPB) literature. It did so by examining the influence of organizational culture on the relationship between affective organizational commitment and UPB.

Using a sample of 710 U.S. service sector employees based on a three-wave data collection design, structural invariance assessment was utilized to evaluate the relationship between affective organizational commitment and UPB across organizational cultures with opposing effectiveness criteria (i.e. focused on stability vs flexibility).

The result indicated a statistically significant positive direct effect between affective organizational commitment and UPB for the stability-focused cultures, while finding a statistically insignificant effect for the flexibility-focused cultures. These results support organizational culture research, which shows that organizational cultures with opposing effectiveness criteria (i.e. stability vs flexibility) can either encourage or discourage ethical behavior.

While leaders and managers encourage employee commitment to the organization, it is important to understand that increased organizational commitment is not limited to positive outcomes. Cultivating elements of flexibility-oriented cultures, like promoting teamwork (as in clan cultures) or fostering innovation and adaptability (as in adhocracy cultures), can be a strategic approach to minimize the chances of UPB among committed employees.

By integrating insights from social exchange theory, Trevino’s interactionist model and the competing values framework, we have contributed to a nuanced understanding of how different organizational cultures can suppress or stimulate UPB.

This study aims to investigate the association between cognitive moral development (CMD) and unethical pro-organizational behaviour (UPB) by taking purchasing employees as research subjects. The moderating effect of perceived leader’s UPB is also explored.

Data were collected through a two-stage questionnaire survey on purchasing employees in companies across a spectrum of industries in Taiwan, and 492 purchasing employees were analysed in the study.

Research findings reveal that employees at the conventional level of CMD are more likely to conduct UPB than those at the pre-conventional and post-conventional levels. Perceived leader’s UPB will moderate the association between CMD and UPB. Employees’ UPB is strongly associated with their CMD when they perceive their leaders as being likely to perform UPB.

Although a variety of factors influencing UPB have been proposed in the literature, none of them have analysed the association between CMD and UPB. However, CMD is one important factor affecting ethical decision-making. The present study can promote further understanding of the role of CMD in UPB and contribute to a growing body of research on CMD and UPB.