Unintentional non-traffic injury and fatal events: Threats to children in and around vehicles

Objective: There have been substantial reductions in motor vehicle crash–related child fatalities due to advances in legislation, public safety campaigns, and engineering. Less is known about non-traffic injuries and fatalities to children in and around motor vehicles. The objective of this study was to describe the frequency of various non-traffic incidents, injuries, and fatalities to children using a unique surveillance system and database.

Methods: Instances of non-traffic injuries and fatalities in the United States to children 0–14 years were tracked from January 1990 to December 2014 using a compilation of sources including media reports, individual accounts from families of affected children, medical examiner reports, police reports, child death review teams, coroner reports, medical professionals, legal professionals, and other various modes of publication.

Results: Over the 25-year period, there were at least 11,759 events resulting in 3,396 deaths. The median age of the affected child was 3.7 years. The incident types included 3,115 children unattended in hot vehicles resulting in 729 deaths, 2,251 backovers resulting in 1,232 deaths, 1,439 frontovers resulting in 692 deaths, 777 vehicles knocked into motion resulting in 227 deaths, 415 underage drivers resulting in 203 deaths, 172 power window incidents resulting in 61 deaths, 134 falls resulting in 54 deaths, 79 fires resulting in 41 deaths, and 3,377 other incidents resulting in 157 deaths.

Conclusions: Non-traffic injuries and fatalities present an important threat to the safety and lives of very young children. Future efforts should consider complementary surveillance mechanisms to systematically and comprehensively capture all non-traffic incidents. Continued education, engineering modifications, advocacy, and legislation can help continue to prevent these incidents and must be incorporated in overall child vehicle safety initiatives.     

煤气管道带气抽堵盲板、开孔接管中的安全技术

生产或使用煤气的工业企业常常需要带气抽堵盲板和开孔接管作业。此类特殊作业存在中毒、着火、爆炸的危险性，为了安全、高效地实施此类作业，本文结合企业15年安全作业的实践，系统地总结了作业的方案制定、主要准备工作、作业过程的控制等方面措施和内容，并总结了相关安全技术问题的一些做法和体会。     

3种运行模式下CAST工艺脱氮性能

以模拟城市污水为处理对象，采用循环式活性污泥法（CAST）反应器，对3种运行模式（M1：常规模式，M2：缺氧好氧模式、M3：缺氧好氧交替模式）下系统的脱氮性能进行了研究，比较了各模式下CAST反应器的氨氮和总氮的去除效率，并对各模式下典型周期内氮基质浓度变化进行了考察，以确定系统的脱氮模式。结果表明，在氨氮去除不成为限制条件（去除率〉90％）的条件下，3种运行模式下系统总氮的平均去除率分别为67．3％、70．6％和82．4％，以缺氧好氧交替模式下的最高；M1、M2和M3均可实现亚硝酸型硝化，但随着温度的升高，亚硝酸型硝化逐渐消失。静态实验分析表明，3种模式下系统的氨氧化速率大小次序为：vN：M1〉vN：M2〉vN：M3，反硝化速率大小次序为：vDN,M2〉vDN,M3〉vDN,M1。     

好氧-缺氧-闲置运行模式处理生活污水

在3个序批式反应器中,利用好氧-缺氧-闲置的运行模式处理实际生活污水,比较了不同曝气时间（2、3和4h）条件下的处理效果,结果表明,在R2（2 h）反应器中成功实现了单级好氧除磷和内聚物驱动的短程硝化反硝化。采用此反应器运行模式,对实际生活污水进行长期处理,反应器的COD、TN和TP的平均去除率分别为85.29%、74.09%和87.97%。本研究表明,在好氧-缺氧-闲置的运行模式下处理生活污水,能成功地实现单级好氧除磷与内聚物驱动的短程硝化反硝化的结合,并且在长期运行的过程中,能稳定地取得较好的脱氮、除磷效率。     

Motorcycle crashes potentially preventable by three crash avoidance technologies on passenger vehicles

Objective: The objective of this study was to identify and quantify the motorcycle crash population that would be potential beneficiaries of 3 crash avoidance technologies recently available on passenger vehicles.

Methods: Two-vehicle crashes between a motorcycle and a passenger vehicle that occurred in the United States during 2011–2015 were classified by type, with consideration of the functionality of 3 classes of passenger vehicle crash avoidance technologies: frontal crash prevention, lane maintenance, and blind spot detection. Results were expressed as the percentage of crashes potentially preventable by each type of technology, based on all known types of 2-vehicle crashes and based on all crashes involving motorcycles.

Results: Frontal crash prevention had the largest potential to prevent 2-vehicle motorcycle crashes with passenger vehicles. The 3 technologies in sum had the potential to prevent 10% of fatal 2-vehicle crashes and 23% of police-reported crashes. However, because 2-vehicle crashes with a passenger vehicle represent fewer than half of all motorcycle crashes, these technologies represent a potential to avoid 4% of all fatal motorcycle crashes and 10% of all police-reported motorcycle crashes.

Discussion: Refining the ability of passenger vehicle crash avoidance systems to detect motorcycles represents an opportunity to improve motorcycle safety. Expanding the capabilities of these technologies represents an even greater opportunity. However, even fully realizing these opportunities can affect only a minority of motorcycle crashes and does not change the need for other motorcycle safety countermeasures such as helmets, universal helmet laws, and antilock braking systems.     

新型单级A/O程序无回流复合膜生物反应器处理氨氮废水的试验

采用单级A/O程序复合膜生物反应器(HSMBR)处理高氨氮废水,研究在低DO浓度下系统对有机物、氨氮和总氮的去除效率。研究结果表明:在低DO浓度下,CODCr、氨氮的平均去除率分别为94.4%和92.8%。由于进水CODCr/TN值仅为2.01,则使得总氮平均去除率仅为69.4%,但是当系统亚硝化累积率从60.5%～67.1%提高到83.5%～86.4%时,系统总氮去除率提高了17.7%。另外,维持低DO浓度可以实现亚硝酸型同时硝化反硝化反应。     

络合吸收结合生物转化去除氮氧化物技术

介绍了络合吸收结合生物转化处理NOx 技术的基本原理和目前的研究进展情况 ,并分析了该技术处理氮氧化物存在的问题和未来发展方向     

花卉废物和牛粪联合堆肥中的氮迁移

以花卉废物和牛粪为原料,进行了温度反馈的通气量控制联合堆肥中的氮迁移中试研究.采用自制的静态好氧床进行一次发酵,过程控制采用温度反馈通气量控制方法,发酵周期20d;采用周期性翻堆进行物料二次腐熟,腐熟周期40d.研究了堆肥过程中总氮、有机氮、无机氮、氨氮、硝氮等氮素形态转化随时间的变化特征及温度反馈的通气量控制对氮迁移的影响.结果表明:堆肥初期的氨化作用和反硝化作用显著,氮素总量损失累计达41.98%,其中主要是有机氮的损失,99.95%的氮损失发生在一次发酵阶段;氮素损失主要是在pH和温度较高条件下的氨气大量挥发造成的.对通风进行有效控制、提高物料C/N及添加酸性物质有望减少N损失.对于C/N较低,硝态氮含量较高的物料堆肥,NH₄⁺-N≤0.04%、NH₄/NO₃≤0.16不能作为腐熟度指标.     

弯管与盲通管冲蚀磨损对比分析研究

为了研究石油管道流向急剧改变处的冲蚀磨损问题,采用DPM模型,通过改变入口流速、颗粒质量流速、颗粒直径,对90°弯管与盲通管的流场分布及冲蚀情况进行数值模拟。结果表明:弯管与盲通管最大冲蚀速率随入口流速的增大呈指数增长,随颗粒质量流速的增大呈线性增长;在50~100 μm粒径范围内,最大冲蚀速率随粒径的增加逐渐减小,在100~300 μm粒径范围内,随粒径的增加而增大;在入口流速、颗粒质量流速、颗粒直径相同的条件下,弯管最大冲蚀速率明显高于盲通管最大冲蚀速率,盲通管的耐蚀性更强;由于流体在盲通管产生涡旋现象,增加了颗粒能量的耗散,从而减小了进入下游管线颗粒的速率,使得颗粒更易积存于盲通段形成堆积层,减小了下游管段冲蚀速率。     

基于盲数理论的湖泊总磷D-BM优化模型

针对湖泊总磷负荷模型中各参数及总磷规划中排污量的不确定性,运用盲数理论,将Dillon模型、盲数模型和费用效益分析模型结合,建立了湖泊总磷规划D-BM优化模型.在总磷规划实例中,当3个近期治理方案的总磷目标浓度分别为0.30,0.20,0.15mg/L时,根据D-BM模型求出3个备选治理方案的费用效益指标分别为0.932、1.480和1.448.选择第2个备选方案为湖泊富营养化最佳治理方案.