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1.
Since 2005, all fatal road traffic crashes in Norway have been analyzed in-depth by multidisciplinary investigation teams organized by the Norwegian Public Roads Administration (NPRA). During the period 2005–2010, 608 drivers of cars or vans were killed in road traffic crashes. Blood samples were collected from 372 (61%) of the drivers and analyzed for alcohol and a large number of psychoactive drugs at the Norwegian Institute of Public Health (NIPH). After coupling the analytical results with the NPRA crash database, 369 drivers with a fatal outcome were identified and included. Alcohol or drug concentrations in blood above the legal limits were found in 39.8% of the drivers who were investigated for alcohol or drug impairment; 33.9% had blood alcohol concentrations above 0.5 g/L or concentrations of drugs above the equivalent Norwegian legal impairment limits or concentrations of amphetamines above 200 μg/L. Among drivers with a fatal outcome who had been impaired by alcohol or drugs, 64.6% were unbelted and 71.7% were speeding when the crash occurred; whereas 24.2% and 33.2% of the sober drivers were unbelted or speeding, respectively. Statistically significant associations were found between impairment by alcohol or amphetamines and driving unbelted or speeding. Excessive speeding is one of the main reasons for road traffic crashes and together with being unbelted the main reasons for a fatal outcome. This behavior might in many cases be due to increased risk-taking or negligence of safety measures as a result of alcohol or drug use.  相似文献   
2.
Market conditions going into this summer continue to reflect the impact of low natural gas prices that have resulted from robust production and near-record levels of natural gas in storage. Moreover, despite modest load growth, regional electric system reserve margins are forecast to be adequate.  相似文献   
3.
The year 2015 was eventful in the energy markets, as oil and natural gas prices fell substantially due to surging supply and strong storage builds. Low gas prices resulted in natural gas generation surpassing coal generation for seven months during 2015. Due to low natural gas prices, for the first time in US history, natural gas power generation surpassed coal-based generation on both a quarterly and monthly basis. Summer temperatures were 8 percent warmer than in 2014, but the 2015–16 winter was relatively mild due to El Niño, which moderated residential and commercial demand at the end of the year.  相似文献   
4.
当今中国是世界上最大的建筑市场.也是一个最大、最充分的建筑师表演的舞台.这里不断涌现出新建筑和新思想。它们既独特又有相似之处.它们出现在动态而又开放的中国大地.影响并冲击着这里的城市环境与建筑文化。[编者按]  相似文献   
5.
本文介绍了应用动态规划方法求解电力变压器任一铁芯直径的最大铁芯截面积,从而为整台产品的优化设计奠定了基础.  相似文献   
6.
绩效管理是对绩效实现过程各要素的管理,是基于企业战略基础上的管理活动。从陕西省电力公司推行全员绩效管理的角度出发,通过对绩效管理的内涵、流程、关键环节、保障措施的深入剖析,理清了绩效管理的思路,对绩效管理的实施能够起到一定的参考作用。  相似文献   
7.
北京2008奥运会倒计时一周年的钟声刚刚响过,2007年8月16~18日,一次国内建筑师交流的盛会在北京市建筑设计研究院举行.……  相似文献   
8.
The "Outline of National Economic and Social Development of the 11th Five-Year Plan" has set forth the target of cutting SO2 emissions by 10% to the year 2010. To realize the target, the National Development and Reform Commission and the State Environmental Protection Administration of China jointly constituted "The 11th Five-Year Plan on SO2Emission Control in Existing Coal-Fired Power Plants" which is not only a completing document for implementing the outline but also an important basis for the state to administer preferential policies to existing coal-fired power plants to equip desulfurization installations.  相似文献   
9.
Job scheduling is a deceptively complex subfield of computer science. The highly combinatorial nature of the problem, which is NP-complete in nearly all cases, requires a scheduling program to intelligently traverse an immense search tree to create the best possible schedule in a minimal amount of time. In addition, the program must continually make adjustments to the initial schedule when faced with last-minute user requests, cancellations, unexpected device failures, etc. A good scheduler must be quick, flexible, and efficient, even at the expense of generating slightly less-than-optimal schedules.

The Space Communications Scheduler (SCS) is an intelligent rule-based scheduling system developed at GE's Advanced Technology Laboratories. SCS is an adaptive deadline scheduler, which allocates modular communications resources to meet an ordered set of user-specified job requests on board the NASA Space Station. SCS uses pattern-matching techniques to detect potential conflicts within a schedule, then resolves these conflicts through algorithmic and heuristic means. As a result, the system generates and maintains high-density schedules without relying heavily on backtracking or blind search techniques. SCS was designed to allocate communication devices on board the Space Station, but its general-purpose scheduling strategy is suitable for many common real-world applications.  相似文献   

10.
聚合醇有效成分的测定   总被引:1,自引:1,他引:0  
为确定各种聚合醇商业产品在钻井液中的准确加量及有效经济成本核算,测定商品中聚合醇有效含量已是当务之急.本文引用非离子表面活性剂分析方法中的四苯硼钠络盐返滴定法测定了聚合醇有效成分的含量.结果表明:应用四苯硼钠(NaPTB)络盐返滴定法测定聚合醇产品中的有效成分是可行的,其原理是非离子型表面活性剂聚合醇在酸性条件与钡离子共存下和四苯硼钠定量反应生成聚合醇-钡-四苯硼钠络盐沉淀.测定化学试剂聚乙二醇的含量为97%~98%,平均相对偏差为0.43%~0.48%,聚合醇的单体及相关物质均不影响测试精度.  相似文献   
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