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31.
A method of checking measuring voltage transformers, based on the use of a combined high-voltage capacitive voltage divider
and a current comparator as standard measuring instruments is considered. The method is used in the UPTN-35 equipment and
enables it to be independently checked during use.
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Translated from Izmeritel'naya Tekhnika No. 8, pp. 52–55, August, 2005. 相似文献
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A new, effective method is proposed for transferring the unit of flow measurement by using more comparators (flowmeters) simultaneously. A device for implementing the method is described and calculations are made for new, more accurate flow-measuring installations. 相似文献
35.
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
36.
《Measurement》2014
A simple method for reducing the uncertainty of reference standards has been proposed for gauge block comparator calibration. Errors due to the reference value of the length difference for mechanical comparator evaluation can be reduced by using the average of two reference values. Two reference values of length difference are obtained by the appropriate combination of three gauge blocks. Errors caused by reference gauges are canceled and averaged. An error reduction effect was successfully demonstrated using an actual mechanical comparator. 相似文献
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通过实验分别考察了满床/空床操作模式对内置颗粒床-旋流耦合分离器分离性能的影响,获得了两种操作模式下的设备压降和捕集效率。通过改变入口粉尘浓度、入口气速和粉尘颗粒种类,发现满床操作条件下的分离效率比空床操作条件下的分离效率高,且前者压降较低。通过对出口粉尘粒径的分析,含有捕集颗粒的内置颗粒床可有效提高5 μm以下的粉尘颗粒的捕集效率,弥补了离心分离的短板。引入性能指数对不同操作模式进行定量分析,验证了满床操作条件下的耦合分离设备具有更好的综合分离性能。 相似文献