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31.
This study compared three representative observational methods for assessing musculoskeletal loadings: Ovako Working Posture Analysis System (OWAS), Rapid Upper Limb Assessment (RULA), and Rapid Entire Body Assessment (REBA). The comparison was based on 209 cases of upper-body musculoskeletal disorders (MSDs) diagnosed by medical doctors. The most awkward/stressful posture in each participant's tasks was assessed using these techniques. Postural loadings were rated more highly by the RULA than by the OWAS and REBA (p < 0.01). The chi-square test and logistic regression analysis showed that only RULA grand score and action level, and REBA action level were associated with MSD work-relatedness (p < 0.01, p < 0.05, and p < 0.05, respectively). The percentage concordant values of the logistic model for the RULA grand score and action level were 52.4% and 44.8%, respectively, while the percentage concordant value for the REBA action level was 22.1%. Therefore, the RULA may be the best system for estimating the postural loads and work-relatedness of MSDs.Relevance to industryWork-related musculoskeletal disorders are the leading cause of workplace disability in the developed countries. For preventing the disorders, quantification of musculoskeletal loads is required. 相似文献
32.
随着我国法治进程的不断推进,群众的维权意识进一步提高.随着消防体制改革,消防救援机构不再具备军队、公安的双重身份,消防执法部门面临的复议、诉讼风险空前加大.文章将结合作者实践经验,探讨行政复议中的常见问题和应对措施. 相似文献
33.
Dynamic response of a beam to a random train of moving forces moving with the same velocity is considered. Unlike a widely used Poisson process model, a more adequate Erlang renewal process is used as a process driving the train of forces. Normal-mode approach is used to convert the problem into that of a renewal driven train of general pulses. Consequently the modal responses are the filtered renewal processes and are expressed as integrals with respect to the response to a single pulse (passage of a force) and to the increments of the counting renewal process. The expressions for the mean values and cross-correlations of modal responses are obtained as single and double integrals, respectively. The results are presented in terms of the renewal density of the underlying Erlang counting process. Mean value and variance of the mid-span deflection of the beam are determined by numerical evaluation of the pertinent integrals. Numerical analysis is carried out for the Erlang processes with integer parameter , and 4 and, for comparison, also for a Poisson process. Different traffic conditions such as the velocity and the mean arrival rate of vehicles are taken into account. 相似文献
34.
Hessam Golmohamadi 《国际能源研究杂志》2021,45(1):938-960
This paper proposes a novel structure to optimize the operational strategies of responsive farms for day‐ahead peak shaving. To achieve the aim, the modern irrigation system of farms, including groundwater, surface water, and booster water pumps, are modeled mathematically. To develop the demand response (DR) potentials of the farms, electrical storage systems, and self‐generation facilities, including thermal distributed generations and on‐farm solar sites, are addressed. In order to facilitate the integration of the agricultural DR programs into the electricity market, a mathematical formulation for agricultural demand response aggregator (ADRA) is suggested. The ADRA participates in the day‐ahead electricity market on behalf of the responsive farms. To overcome the price uncertainty of the electricity market, a robust optimization approach is addressed. This approach determines the robust decisions of farms in the worst‐case realizations of the uncertain electricity price. Regarding on‐farm solar sites located in rural areas, a data‐driven approach is used to estimate the solar power generation of a significant number of sites without needing to install costly communication and measurement infrastructures. Finally, the proposed approach is implemented on agricultural lands in the northeast of Iran. The numerical results show that the suggested approach provides day‐ahead peak shaving for the power systems meeting the crop's water requirements. 相似文献
35.
David J. Devlaeminck 《国际水资源开发杂志》2021,37(1):162-177
ABSTRACT In spite of groundwater’s growing importance, the 2008 Draft Articles on the Law of Transboundary Aquifers have yet to be fully adopted by the international community. As states contemplate the future of the draft articles, this article aims to reassess them through the lens of the legal principle of reciprocity. To do so, this article provides a framework for the analysis of law via reciprocity, followed by its application to the draft articles. Although this article primarily finds that they follow a reciprocal structure, it also identifies areas to be revisited, including sovereignty and recharge zone states. 相似文献
36.
一年一度的“中国设计理论与‘中国工匠’培育高端论坛”旨在探讨、研究与实践中国设计理论体系的当代建构问题,以期对中国未来发展做出中国设计理论界自己的努力和贡献。本研究聚焦设计与技术之内在逻辑关系的探讨,重点探索中国设计理论与技术创新问题。系统考察与研究中国设计理论的概念、基本内涵、特征及其价值;深入探讨如何把握技术创新的基本内涵、价值追求及其当代意义;特别考察中国设计理论建设中的技术创新问题。本次的亮点是设计治理理论问题的提出与探索,具有极大的现实价值和理论意义。这些问题正是中国当代文化转型发展的重大理论问题。本研究尝试性探讨技术设计学体系建构的基本问题。 相似文献
37.
38.
鲁春梅 《北京印刷学院学报》2006,14(6):33-36
作为著名作家和出色的编辑家、出版家的巴金,在期刊编辑生涯中遇到各色对自己后来期刊编辑思想的形成产生重要影响的人物,这些人物在巴金的期刊编辑思想形成中起到了举足轻重的作用. 相似文献
39.
Deduced the relationship between the power factor (PF) and the angular frequency according to the simplified equivalent circuit of asynchronous motor, forming a power factor auto-control system. An anti-interference circuit was also introduced in the middle voltage link of inverter to avoid the shift of the optimum PF point caused by the change of the load and the reliable run of the control system was assured. The experiment results show that it has a good self-adaptation in the whole scope of speed adjustment and an obvious economization on energy while it runs under load. 相似文献
40.