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本文结合国标转化过程和实验室能力验证经历,介绍了电驱动道路车辆动力双层电容电气特性试验条件和要求。供实验室和相关产品的供需双方参考。 相似文献
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Marc Scheid Christian Kusche Volkmar Schröder Uli Barth 《Journal of Loss Prevention in the Process Industries》2013,26(6):1542-1548
Several safety characteristics of dusts are determined in the 20-L-sphere (also known as SIWEK Chamber) according to international standards. Dust cloud ignition is carried out using pyrotechnical igniters. Due to various disadvantages of such igniters the need for alternative ignition sources arises again and again. An alternative could be an ignition source which is known as “exploding wire” or “fuse wire”. The paper presents test results of a comparative study between both ignition sources for the determination of the safety characteristics “Maximum Explosion Pressure” and “Maximum Rate of Explosion Pressure Rise” of five selected dusts in the 20-L-sphere. In addition to that the ignition mechanisms of both ignition sources were analyzed by high speed camera recordings and the ignition energy was determined with electric and calorimetric recordings. The paper shows results of measurements of the ignition energy of both ignition sources as well as sequences of the flame propagation. 相似文献
595.
Marek Dźwiarek 《International journal of occupational safety and ergonomics》2013,19(3):363-384
The Double Penetration Method (DPM) method of measuring ESPD (Electrosensitive Protective Device) response time was presented by Dzwiarek (1997). Calibrating the measuring equipment is a crucial stage of the procedure. Experimental verification of theoretical predictions is also crucial. For calibration purposes, a device simulating real ESPD operation thus enabling a correct setting of the response time was designed (Dzwiarek, 1997).Theoretical analysis has shown that measuring ESPD response time with the DPM is subject to localisation errors made in the localisation of the detection zone border, rod position measurement errors made during highspeed penetration, and time delay measurement errors. The values of all those components of the total error have been determined experimentally using the calibrating device. Measurements have been taken under conditions as close to real ones as possible proving that the total measurement error is really enclosed within the assumed limits. 相似文献
596.
Abstract Along with the rapid growth of economy in the postreform period after 1979, China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society. This article explores an effective mechanism of managing resource and environment in China. It examines some major resource and environmental issues, and constructs a framework of institution innovation to cover three sectors (government, market and society). In addition, the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period. We argue that the combination of market regulation, government intervention and public participation is an effective way of allocating resource and protecting environment. Some suggestions are put forward to balance the relationship between them, including coordinating role of government and market, building platform for market operation and creating an atmosphere of public participation. 相似文献
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王爱冬 《中国环境管理干部学院学报》2002,12(1):48-52
本文从社会转型期容易产生腐败问题为切入点,分析了加强和改进政治权力制约的必要性,并根据我国的实际情况,提出了为治理和减少腐败而加强和改进对政治权力制约的对策和办法。 相似文献
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How safe are standard certified motorcycle safety helmets? Malaysian postal delivery riders scenario
Objective: The objective of this study was to determine the proportion of motorcycle safety helmets (MSHs) used by postal delivery riders (PDRs) that comply with the Standards and Industrial Research Institute of Malaysia’s (SIRIM) MSH standard guidelines and identify factors that contribute toward compliance of used MSHs with the standards.Methods: The presence of SIRIM certification label, the status of MSH, type of chinstrap, MSH crash history, and duration of MSH use were observed. The dependent variable was the results of the SIRIM testing procedures (SIRIM tests). MSHs that passed the SIRIM tests were considered “standard certified” MSHs.Results: The odds of the complimentary MSHs passing all of the SIRIM tests were 3.7 times the odds of the self-purchased MSHs passing the tests. The odds of MSHs with the SIRIM certification label passing all of the SIRIM tests were 24.2 times the odds of MSHs without the SIRIM certification label, and the odds of MSHs used <3?years passing the SIRIM tests were 3.75 times the odds of the MSHs used ≥3.8?years.Conclusion: PDRs provided with complimentary MSHs with the SIRIM certification label by the employer for their daily delivery routines and duration of MSH used for less than 3 years were found to be safe MSHs for male occupational riders in Malaysia. 相似文献
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