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991.
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
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994.
《Energy Policy》2016
Adequately accounting for interactions between Low Carbon Technologies (LCTs) at the building level and the overarching energy system means capturing the granularity associated with decentralised heat and power supply in residential buildings. The approach presented here adds novelty in terms of a realistic socioeconomic differentiation by employing dwelling/household archetypes (DHAs) and neighbourhood clusters at the Output Area (OA) level. These archetypes are combined with a mixed integer linear program (MILP) to generate optimum (minimum cost) technology configurations and operation schedules. Even in the baseline case, without any LCT penetration, a substantial deviation from the standard load profile (SLP) is encountered, suggesting that for some neighbourhoods this profile is not appropriate. With the application of LCTs, including heat pumps, micro-CHP and photovoltaic (PV), this effect is much stronger, including more negative residual load, more variability, and higher ramps with increased LCT penetration, and crucially different between neighbourhood clusters. The main policy implication of the study is the importance of understanding electrical load profiles at the neighbourhood level, because of the consequences they have for investment in the overarching energy system, including transmission and distribution infrastructure, and centralised generation plant. Further work should focus on attaining a superior socioeconomic differentiation between households. 相似文献
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996.
煤气放空造成制氧机大面积停车是安钢制氧史上第一次,对事故当时情况和应急处理进行了详述,为同类事故预防和处理提供借鉴。 相似文献
997.
James L. Dolby 《技术计量学》2013,55(3):317-325
The choice of non-linear transformations in the analysis of data can frequently be simplified by restricting the possible transformations to a particular family. Tukey has shown that the “simple family” has many desirable properties from this point of view. This family can be represented as the set of solutions to a third order differential equation and the constant of this equation provides a convenient index of the family. This index may be approximated by substituting the given data into the corresponding difference equation. The resulting approximation can then be used for rough solutions or as a starting value for the iterative solution of the maximum likelihood equations given by Turner. Two examples are provided to demonstrate the procedure. 相似文献
998.
采用计算流体力学(CFD)技术,对220kV主变压器室温度场进行模拟计算,对比分析了不考虑辐射条件和考虑辐射条件的室内温度场的模拟结果,得出辐射条件是模拟220kV主变压器室温度场分布必须考虑的条件之一. 相似文献
999.
针对某透平机组主油泵频繁发生故障,进行了原因分析,找出了主因,并对其进行了优化改造,有效避免了事故的发生。 相似文献
1000.
本文通过PKPM的实际算例,并结合抗震规范(2010版)5.2.5条的条文说明,阐述动位移比例因子的不同取值对结构剪重比调整的影响。 相似文献