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本项目结合湖北省科技计划自然科学基金项目“混凝土结构使役环境的智能模拟”,在WTST-150试验机硬件平台基础上,以LabVIEW8.5为开发平台,设计了一套混凝土结构使役环境中温度智能模拟LabVIEW软件,主要包括能初始化程序、温度采集与显示子程序、温度PID控制子程序、温度存储和查询子程序。经投入实验验证,该软件能实现实时曲线显示、温度控制、试验状态和保存试验数据、数据查询、手动加热、分配温度通道、PID控制参数整定、制冷、读入温度曲线等功能。具有实时在线循环检测、采集数据、响应快速等优点,并具有良好的故障诊断能力和可维护性以及超强的纠错能力。本软件完善了WTST-150试验机的温度控制系统,使其更加符合实际工况。 相似文献
413.
Melissa L. McCarthy Author Vitae Peilin Sheng Author Vitae 《Journal of Safety Research》2009,40(3):227-232
Objective
To examine the validity of police-reported alcohol data for drivers involved in fatal motor carrier crashes.Material and Methods
We determined the availability of blood alcohol concentration (BAC) and police-reported alcohol data on 157,702 drivers involved in fatal motor carrier crashes between 1982 - 2005 using Fatality Analysis and Reporting System (FARS) data. Drivers were categorized as motor carrier drivers if they operated a vehicle with a gross vehicle weight rating of greater than 26,000 pounds. Otherwise, they were classified as non motor carrier drivers. The sensitivity and specificity of police-reported alcohol involvement were estimated for both driver types.Results
Of the 157,702 drivers, 18% had no alcohol information, 15% had BAC results, 42% had police-reported alcohol data, and 25% had both. Alcohol information varied significantly by driver, crash, and vehicle characteristics. For example, motor carrier drivers were significantly more likely (51%) to have BAC testing results compared to non motor carrier drivers (31%) (p < 0.001). The sensitivity of police-reported alcohol involvement for a BAC level ≥ 0.08 was 83% (95% CI 79%, 86%) for motor carrier drivers and 90% (95% CI 89%, 90%) for non motor carrier drivers. The specificity rates were 96% (95% CI 95%, 96%) and 91% (95% CI 90%, 91%), respectively.Conclusions
The sensitivity and specificity of police-reported alcohol involvement are reasonably high for drivers involved in fatal motor carrier crashes. Further research is needed to determine the extent to which the accuracy of police-reported alcohol involvement may be overestimated because of verification bias.Impact on the Industry
Based on the results of this study, the federal government should continue to work with states to strengthen their strategies to increase chemical testing of all drivers involved in fatal crashes. 相似文献414.
USB KEY的体系结构分析及安全策略研究 总被引:1,自引:0,他引:1
随着信息技术的发展,网络安全技术日益受到广泛关注.以PKI为基础的USBKEY身份认证技术逐步成为主流安全解决方案.本文首先分析了USB KEY技术的原理和体系结构.其次针对其存在的安全漏洞提出切实可行的安全策略,增强了USB KEY的安全机制. 相似文献
415.
INTRODUCTION: Gender differences were investigated in a sample of persons (N=34,755) who completed the driver's license theory test in the Netherlands. RESULTS: Contrary to recent findings from Sweden, no gender differences were found. IMPACT OF INDUSTRY: The present study signifies the importance of standardization in driver testing. 相似文献
416.
可燃气体(液体蒸气)爆炸测试装置的改进研究 总被引:3,自引:2,他引:1
以可燃气体(液体蒸气)爆炸测试装置改进为主线,综述国内外各种测试装置的优缺点。对不同装置、测试方法以及测试原理进行比较分析,研讨可燃气体爆炸的特点和爆炸参数测试方法以及对现有测试装置的改进方案。即对20 L爆炸测试装置的配气系统和控制系统进行了合理改进,使引射混合配气与循环混合配气相结合,使可燃气体(液体蒸气)与空气混合更均匀,控制操作更简便,还指出了今后研究工作中应注意的一些问题和研究重点。 相似文献
417.
In this paper, we investigate the Precautionary Principle (PP) in action. Precaution is a fairly new concept in environmental
policy. It emerged back in the 1960s but did not consolidate until the 1980s, as it formed part of the major changes taking
place in environmental policies at that time. The PP is examined in three contexts. Firstly, we look at the meaning of the
concept and how it is disseminated through the media and public discourses to the political arenas of Denmark. Then we examine
how the idea is adopted to the political level. Thirdly, we look briefly at the first Danish translation of the principle
into a practical context, which includes translations into concrete scientific practices. It is concluded that if the PP shall
be more than a simple “idea” or a frequently used “term,” emphasis must be put on the transformation of the concept into concrete
practices, like e.g., the alternative testing regimes that we show in the case of plant growth-retarding pesticides presented
in this paper. 相似文献
418.
François Vialard Giuseppe Simoni Denise Molina Gomes Azzedine Abourra Simona De Toffol Fabrice Bru Maria Carmen Martinez Romero Lucio Nitsch Philippe Bouhanna Livia Marcato Thomas Popowski Beatrice Grimi Jose Antonio Martínez-Conejero B. Benzacken Rita Genesio Francesca R. Grati 《黑龙江环境通报》2012,32(4):329-335
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