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91.
Musculoskeletal disorders (MSD) have a high impact on the health of dual role workers (student and work). The aim of this study was to analyse risk factor (active pauses and job position) associated with MSD in postgraduate students, Bogotá 2016. This Cross-sectional study was conducted in a random sample of 304 college graduate students and statistical analysis in SPSS version 24. We found that significant differences between non-performing active pauses and neck symptoms (P = 0.007), not stretching vs neck symptoms [OR = 2.4048 (1.0133–5.707)]; laptop use vs eyes [OR = 2.7132 (1.457–5.0526)], shoulders [OR = 10.6364 (4.9905–22.6697)], elbows (P = 0.04); non-mouse usage vs elbows (P = 0.028), hand-wrist (P = 0.043); non-forearm support vs lower back (P = 0.009). Results suggest association between non-performing active pauses, stretching and neck; use of laptop and eyes, shoulders and left elbow, non-mouse usage and on elbow and hand/right wrist, no forearm support on table and lower back. Symptom changes in the upper and lower limbs were identified. 相似文献
92.
为了合理准确地评价煤矿冲击地压危险性,在现有评价冲击地压危险性实例的基础上,从煤矿地质因素和开采因素2个方面,选取10个主要的影响指标,利用熵权法和指标相关性权重法分别计算影响冲击地压危险性的各评价指标权重,再根据组合赋权的方法得出各指标的综合权重,构建基于逼近理想解理论的冲击地压危险性评价模型。以重庆砚石台煤矿为例,选取20组评价冲击地压危险性样本数据进行分析,确定评价冲击地压危险性的最优和最劣状况,然后计算出各个评价方案与最优和最劣状况的距离,最后综合最优与最劣距离,确定评价对象的相对贴近度。应用结果表明:评价结果与实际情况一致,且该模型相较其他模型的评价结果更加科学准确,表明该方法有良好的实用价值。 相似文献
93.
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95.
The ‘fit-for-purpose’ (FFP) approach was developed to respond to the challenges that the creation of a sustainable land administration system (LAS) faces. FFP has proved its value in integrating technological innovations such as unmanned aerial vehicles (UAVs) in LAS. Technological innovations need to consider the governance context when being implemented. Understanding the relevance of the FFP approach and acknowledging the importance of the governance context, this research applies the ‘Fit-for-purpose governance assessment framework’ (FGAF). FGAF helps to understand the challenges that the implementation of UAVs can face in the LAS in Kenya. This governance assessment is based on 16 semi-structured in-depth interviews, three one-day workshops with local stakeholders and UAVs pilot studies to test the technology. The findings suggest that there are major and minor challenges concerning different attributes of FFP qualities. The governance context across counties is fragmented with a high degree of uncertainty and uneven capacity conditions. There are overlapping responsibilities and trust issues among the different actors. Participation of private and non-governmental actors is limited. Yet, steps have been taken toward the adoption of innovative approaches. Although financial resources are limited, the diversity of local and international stakeholders can work as a leverage point to support the implementation of UAVs in the mid and long-term. 相似文献
96.
《International Journal of Hydrogen Energy》2021,46(57):29724-29731
When comparing the life-cycle environmental performance of hydrogen energy systems, significant concerns arise due to potential methodological inconsistencies between case studies. In this regard, protocols for harmonised life cycle assessment (LCA) of hydrogen energy systems are currently available to mitigate these concerns. These protocols have already been applied to conventional hydrogen from steam methane reforming as well as to a large number of both fossil and renewable hydrogen options, allowing robust comparisons between them. However, harmonised life-cycle indicators of nuclear-based hydrogen options are not yet available in the literature. This study fills this gap by using the recently developed software GreenH2armony® to calculate the harmonised carbon, energy and acidification footprints of nuclear-based hydrogen produced through different pathways (viz., low-temperature electrolysis, high-temperature electrolysis, and thermochemical cycles). Overall, the harmonised case studies of nuclear-based hydrogen show a generally good performance in terms of carbon footprint and acidification, but an unfavourable performance in terms of non-renewable energy footprint. 相似文献
97.
Karin G. M. Lenssen Aalt Bast Alie de Boer 《Comprehensive Reviews in Food Science and Food Safety》2019,18(4):910-922
The efficacy of botanicals in medicines can be substantiated with evidence on traditional use, whereas in foodstuffs, this is often not possible. In Europe, for example, the evaluation and subsequent authorization of health claims on herbal dietary supplements (HDS) have been put on hold by the European Commission. This study aims to analyze the role of evidence on traditional use in international legal frameworks of foods and pharmaceuticals. Both legal sources as well as scientific studies offering insights into these regulatory frameworks were included into the analysis. The international approach toward evidence on traditional use for substantiating efficacy of botanicals varies highly. For herbal medicines, substantiating efficacy with evidence on traditional use is possible in all studied jurisdictions, except for Japan and the United States. HDS efficacy can only be substantiated with evidence on traditional use in India and New Zealand, although the enforcing authorities do not describe which data are required. Australia and Canada regulate botanicals in a separate “borderline” category from foods and pharmaceuticals. Both jurisdictions allow for substantiating efficacy with evidence on traditional use. This study's second objective was to assess the applicability of the international approaches in the European legal framework, in light of the ongoing political debate regarding the use of traditional evidence. Implementation of the analyzed international approaches would require major revisions of the current European legal framework. This review of international approaches might, however, aid in deciding upon future approaches for substantiating health claims with evidence on traditional use. 相似文献
98.
本文介绍“风险矩阵法”进行风险分级工作的基本思路,结合水泥厂的生产特点通过危险有害因素辨识,获得危险源分布情况,采用风险矩阵法对风险进行评估,按风险值将风险等级划分为重大风险、较大风险、一般风险和低风险,为水泥生产企业的安全风险分级工作提供参考。 相似文献
99.
Arising out of the challenge for Local Authorities (LAs) to operate sustainable systems of work, is to avoid the creation of ill-health including the most significant causes of physical absence, musculoskeletal disorders (MSDs).The study's aim was to compare the reliability of the manual handling element of the Health and Safety Executives (HSEs) risk comparator tool for different domestic waste collection methods with self-reported pain via body-mapping and MSD ill health absence rates. Participatory body-mapping exercises were carried out in five LAs with one LA resurveyed, six months after the move from 35 and 50 L containers to a wheeled bin recycling service.The lowest levels of self-reported pain were for services designed with 240l wheeled bins excluding glass; the highest levels were for services that included 100l of garden waste sacks and recycling boxes. Industry data supports previous laboratory studies showing wheeled bins to be associated with less MSD outcomes than boxes, baskets and sacks.Triangulation of data established a statistically significant correlation of 0.85 (Pearson) between average pain-count (APC) and the mean MSD absence rates, with a strong correlation of 0.77 (Spearman) between APC and risk rating. The correlation is moderate, 0.49 (Spearman) between MSD absence and risk rating, reflecting possible intervening variables and a low participation rate by LAs.The contribution of this study is to improve the design of sustainable waste collection strategies to minimise MSD associated absence. In the absence of reliable absence data, body mapping should be used as a proxy method of assessing MSD risk. 相似文献
100.
To form a high-performance video quality predictor, we developed a framework for full-reference (FR) video quality assessment that integrates Spatio-temporal slice analysis (STS) to create a high-performance predictor of video quality. However, both gradient and Gabor are spatial–temporal structural capturers used for the simultaneous extraction of both spatial and temporal features. In this paper, we proposed a novel VQA algorithm via a joint model of gradient magnitude and Gabor features (JMG) between the STS images of the reference videos and their distorted counterparts to assess the degradation of video quality effectively. Firstly, gradient magnitude and the Gabor filter were constructed to extract the spatiotemporal features of the video sequence. However, the two-feature model combined to predict the perceptual quality of frames. This new proposed VQA model is known as the horizontal and time STS (HT-JMG) model. To further investigate the influence of spatial dissimilarity, we combined the frame-by-frame spatial T-JMG(S) factor with the HT-JMG and propose another VQA model, called the time, horizontal, and vertical STS (THV-JMG) model. Finally, the results of the experiment showed that the proposed method has a strong correlation with subjective perception and is competitive with state-of-the-art full reference VQA models. 相似文献