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991.
合理构建视频显示终端(VDT)作业疲劳工间休息制度 总被引:4,自引:0,他引:4
为了减少VDT(视频显示终端)作业对操作者健康的负面影响,合理地安排工作和休息时间以及设计良好的工作环境有助于减轻、缓解或消除VDT作业的疲劳。通过多项VDT数据输入作业实验,依据作业者作业能力变动的规律性,对不同类型的VDT作业者可能需要设置不同的工间休息制度。经过对实验数据的分析,数据输入的工作主要是信息接受和信息输出,属于事务性脑力劳动。只要合理地安排工作和休息时间以及设计良好的工作环境,就可以减少VDT对眼睛、骨骼及肌肉的疾患发生。 相似文献
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刘湘 《中国环境管理干部学院学报》2001,(Z1)
本文以秦皇岛市大里营村11户村民诉北京铁路局噪声污染一案为例,分析《噪声污染防治法》关于环境噪声污染的规定在适用中存在的问题,建设立法修改或出台司法解释,以保障公民的环境权。 相似文献
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Esther Guetta 《黑龙江环境通报》2006,26(7):635-636
Toward the end of the twentieth century it was discovered that cell-free fetal DNA sequences could be detected in maternal blood plasma. Initially, Y-chromosome sequences originating from male fetuses were targeted in cell-free DNA extracted from maternal plasma in order to demonstrate proof of this concept towards the development of noninvasive prenatal diagnosis methods. Clinical application of this approach is now possible. Fetal sex can be detected through a procedure that is noninvasive with respect to the fetus. Specifically, the presence of Y-chromosome sequences in maternal blood plasma indicates that the fetus is male, whereas lack of a signal will indicate that the fetus is female. Fetal sex can be detected very early, from at least the 7th week of pregnancy (and even earlier, according to several studies), about two months before this information is available through ultrasound scanning. Although the controversial issue of fetal sexing is not new, it is expected that with the availability of an accurate noninvasive test, public interest will rise. It is therefore imperative that an authorized committee of experts in each country generates an official policy regarding application of the test. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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We believe non-invasive prenatal diagnosis is about to have a massive impact on the way fetal medicine is practised. There will be many great advantages and improvements, but the technology also has the potential to be used for non-medical reasons such as sex selection and paternity testing. We discuss some of the issues that may face obstetricians in the future as a result of this emerging technology. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
999.
Global mitigative and adaptive efforts have not been able to effectively address the adverse impacts caused by climate change. Therefore, a direct solution is needed to address the significant resulting loss and damage (L&D). During the United Nations Framework Convention on Climate Change held in Doha in 2012, the issue of responding to L&D arising from climate change gained sudden traction and became one of the key issues that affected the outcome of the convention. In this paper, a study on the definition and connotations of L&D arising from climate change was conducted, together with an analysis of its relationship with related concepts, namely impacts, vulnerability, and risks. This led to the proposal of an L&D conceptual model that is more comprehensive, with the recognition of the need to address the issue through effective supplementation of existing mitigative and adaptive efforts. A systematic elaboration of an L&D response mechanism was made based on politics, law, and the market, leading to a preliminary presentation of a possible format for an L&D mechanism. Potential academic research directions for L&D were also proposed that could serve as references for the establishment of international and national L&D response mechanisms and related research. 相似文献
1000.
《Journal of Manufacturing Processes》2014,16(3):391-404
Electrohydraulic forming (EHF) is a high energy rate forming process in which the strain rate in the sheet metal can vary from 5 × 102 to 105 s−1 depending on various factors. Several mechanisms have been reported to cause an improvement in formability in EHF such as material deformation mechanisms, inertial effects and the dynamic impact of the sheet against the die. EHF is a complex high speed forming process and experimental work alone is not sufficient to properly understand this process. To understand the variation of some influential variables in EHF, electrohydraulic die-forming (EHDF) and free-forming (EHFF) of DP590 dual phase steel were simulated in ABAQUS/Explicit by considering the fluid/structure interactions. Three-dimensional finite element simulations were conducted by modelling the water with Eulerian elements with a view to investigating the effect of released energy on the sheet deformation profile history, strain distribution, loading path and damage accumulation type. The Johnson–Cook constitutive material model was used to predict the sheet behaviour and the parameters in this model were calibrated based on experimental test results available for DP590 at various strain rates. The Johnson–Cook phenomenological damage model was also used to predict the ductile failure (damage accumulation) in both EHDF and EHFF. Predicted final strain values and damage accumulation type showed good agreement with the experimental observations. 相似文献