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91.
本文把模糊线性规划方法引入灾害对策的研究当中。着重讨论了疏散人口和疏散地点间的关系,简单介绍了模糊疏散距离及其初步确定方法。 相似文献
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93.
目的研究低成本高效慢速烤燃试验方法。方法利用自主研发的一套慢速烤燃试验装置,以1℃/min和3.3℃/h升温程序作为对比试验,设置几种三阶段升温程序,对JBO-9013和JH-14炸药进行慢速烤燃试验,以此获得不同升温程序下试样的响应温度和响应等级。结果 1℃/min、3.3℃/h、三阶段(100/150/193℃)升温程序下,JBO-9013响应温度分别为243.1、199.5、199.8、201.4、193.0℃,响应等级均为燃烧反应;JH-14响应温度分别为211.0、186.0、191.7℃,响应等级均为爆轰反应。结论升温程序对JBO-9013和JH-14响应温度和响应剧烈程度均有影响。与GJB8018—2013中1℃/min升温程序相比,三阶段升温程序与MIL-STD-2105D和STANAG 4439中3.3℃/h烤燃试验结果吻合度较高。因此,三阶段升温程序具有缩短试验周期、提高试验效率和降低试验成本的作用。 相似文献
94.
于连荣 《中国人口.资源与环境》1996,6(4):51-55
社会主义市场经济体制的建立和完善,给计划生育工作带来了一系列的新情况、新问题。因此,把计划生育工作纳入法制的轨道显得尤为重要。本文分析了我国计划生育工作靠行政约束的局限性;总结了市场经济体制下,计划生育工作面临的新特点;阐述了加强计划生育法制建设的紧迫性和可行性;并提出了计划生育立法的基本思路 相似文献
95.
The long-term water quality monitoring program implemented by the Massachusetts Water Resources Authority in 1992 is extensive
and has provide substantial understanding of the seasonality of the waters in both Boston Harbor and Massachusetts Bay and
the response to improvements in effluent quality and offshore transfer of the effluent in September 2000. The monitoring program
was designed with limited knowledge of spatial and temporal variability and long-term trends within the system. This led to
an extensive spatial and temporal sampling program. The data through 2003 showed high correlation within physical parameters
measured (e.g., salinity, dissolved oxygen) and in biological measures such as chlorophyll fluorescence. To address the potential
sampling redundancies in the measurement program, an assessment of the impact of reduced levels of monitoring on the ability
to make water quality decisions was completed. The optimization was conducted by applying statistical models that took into
account whether there was evidence of a seasonal pattern in the data. The optimization used model survey average readings
to identify temporal fixed effects, model survey-average-corrected individual station readings to identify spatial fixed effects,
corrected the individual station readings for temporal and spatial fixed effects and derived a correlation model for the corrected
data, and applied the correlation model to characterize the correlation of annual average readings from reduced monitoring
programs with true parameter levels. Reductions in the number of sampling stations were found less detrimental to the quality
of the data for annual decision-making than reductions in the number of surveys per year, although there is less of a difference
in this regard for dissolved oxygen than there is for chlorophyll. The analysis led to recommendations for a substantially
lower monitoring effort with minimal loss of information. The recommendation supported an annual budget savings of approximately
$183,000. Most of the savings was from fewer surveys as approximately $21,000 came from the reduction in the number of stations
monitored from 21 to 7 and associated laboratory analytical costs. 相似文献
96.
PROBLEM: After decreasing to a historic low in 1997, motorcycle crash-related fatalities are increasing. Although causes remain unclear, motorcycle rider education and licensing play key roles in reducing motorcycle crashes and injuries. Yet, little is known about what constitutes effective rider training and licensing. This study develops a model of best practices in motorcycle rider education and licensing and combines primary and secondary data to identify states that most closely adhere to this model. Evidence on the validity of the model is also examined. METHOD: States were rated along three areas of best practices: (a) program administration; (b) rider education; and (c) licensing based on 2001 data collected for a National Highway Traffic Safety Administration (NHTSA)-sponsored study. RESULTS: Results indicate wide variation in states' adherence to best practices; several states meet most, others very few. When the areas of best practices are considered separately, a state tends to behave similarly on all three. Initial evidence supports the validity of the model, with high best practices states having the lowest rates of motorcycle fatalities. IMPACT ON TRAFFIC SAFETY: As motorcycle-related crashes increase and state and federal support for rider education programs diminishes, it is critical that states identify deficiencies in their program and learn from successful states about efficient, cost-effective strategies for increasing best practices in motorcycle rider education and licensing. 相似文献
97.
简要地介绍了安徽淮南某矿回采工作面发生的1起重大冒顶事故,从地质、技术、装备、管理以及认识等方面分析r事故发生的原因,并提出了防治顶板事故的6项措施。 相似文献
98.
王志安 《安全.健康和环境》2004,4(1):13-15
介绍了在石油生产设备设施的建设安装和检修动火过程中 ,工程技术人员创造发明的防护盲板、防护接地、加装管道扫线接口和绝缘螺栓4种防护方法 ,简要叙述它们的结构、用途和适用范围 ,为油田施工单位进行动火作业提供技术参考。 相似文献
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100.