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671.
Objective: The objective of this study was to investigate whether the 5-point harness or the impact shield child restraint system (CRS) or both have the potential to cause chest injuries to children. This is determined by examining whether the loading to the chest reaches the internal organ injury threshold for children.

Method: The chest injury risk to a child occupant in a CRS was investigated using Q3 dummy tests, finite element (FE) simulations (Q3 dummy and human models), and animal tests. The investigation was done for 2 types of CRSs (i.e., the impact shield CRS and 5-point harness CRS) based on the UN R44 dynamic test specifications.

Results: The tests using a Q3 dummy indicated that although the chest deflection of the dummy in the impact shield CRS was large, it was less than the injury threshold (40 mm). Computational biomechanics simulations (using finite element FE analysis) showed that the Q3 dummy's chest is loaded by the shield and deforms substantially under this load. To clarify whether chest injuries due to chest compression can occur with an impact shield or with the 5-point harness CRS, 7 experiments were performed using Tibetan miniature pigs with weights ranging from 9.7 to 13 kg. Severe chest and abdominal injuries (lung contusion, coronary artery laceration, liver laceration) were found in the tests using the impact shield CRS. No chest injuries were present when using the 5-point harness CRS.

Conclusion: When using the impact shield CRS, the chest deformed substantially in dummy tests and FE simulations, and chest and abdominal injuries were observed in pig tests. It is possible that these chest injuries could also occur to child occupants sitting in the impact shield CRS.  相似文献   

672.
Objective: Thoracic side airbags (tSABs) were integrated into the vehicle fleet to attenuate and distribute forces on the occupant's chest and abdomen, dissipate the impact energy, and move the occupant away from the intruding structure, all of which reduce the risk of injury. This research piece investigates and evaluates the safety performance of the airbag unit by cross-correlating data from a controlled collision environment with field data.

Method: We focus exclusively on vehicle–vehicle lateral impacts from the NHTSA's Vehicle Crash Test Database and NASS-CDS database, which are replicated in the controlled environment by the (crabbed) barrier impact. Similar collisions with and without seat-embedded tSABs are matched to each other and the injury risks are compared.

Results: Results indicated that dummy-based thoracic injury metrics were significantly lower with tSAB exposure (P <.001). Yet, when the controlled collision environment data were cross-correlated with NASS-CDS collisions, deployment of the tSAB indicated no association with thoracic injury (tho. MAIS 2+ unadjusted relative risk [RR] = 1.14; 90% confidence interval [CI], 0.80–1.62; tho. MAIS 3+ unadjusted RR = 1.12; 90% CI, 0.76–1.65).

Conclusion: The data from the controlled collision environment indicated an unequivocal benefit provided by the thoracic side airbag for the crash dummy; however, the real-world collisions demonstrate that no benefit is provided to the occupant. This has resulted from a noncorrelation between the crash test/dummy-based design taking the abstracting process too far to represent the real-world collision scenario.  相似文献   

673.
674.
NF和RO对致突变物和无机离子去除效果比较   总被引:3,自引:0,他引:3  
以自来水为原水,采用反渗透和纳渗进行深度处理试验研究,比较了2种膜对致突变物和无机离子的去除率。结果表明,RO和NF均能使Ames试验呈阳性的水转变为阴性;NF对一价阳离子(K^+、Na^+)的去除率比RO低10%左右,对二价阳离子(Ca^2+、Mg^2+)的去除率略低于RO,NF比RO能多保留一些离子。  相似文献   
675.
TS-35型氨法脱硫工业化试验及其经济性分析   总被引:3,自引:1,他引:2  
对TS 35型氨法脱硫工艺进行了系统的工业化试验研究 ,该脱硫工艺对原有锅炉参数影响小 ,氨水消耗量少 ,阻力小 ,能耗低 ,脱硫效率可达 80 % ,几乎无废水排放 ,适用于中小型锅炉的脱硫 ,但有可能会加剧锅炉尾部设备的腐蚀。对于大型锅炉 ,必须考虑副产品硫酸铵的销路和价格问题。通过经济性分析 ,得出目前实施的排污收费制度存在一定的弊病 ,有必要完善以总量控制为目标的排放许可权交易制度  相似文献   
676.
结合工程装备维修器材保障工作的实际情况,对扫雷车电子类备件贮存失效模式及影响因素进行了定性分析,提出了电子类备件技术性能测试方案,研究设计了相应的检测平台及适配器,对工程装备维修器材贮存质量管理及控制进行了初步探索。  相似文献   
677.
基于新疆地区42个气象站点1971-2016年逐日温度数据资料,选取世界气象组织(WMO)推荐的10个极端温度指标,使用线性趋势法、克里金插值法和Mann-Kendall突变检验等方法,分析该地区极端温度指数在时间和空间上的变化规律.结果 表明:新疆地区1971-2016年间4个极端高温指数均呈现出明显的上升趋势,除极...  相似文献   
678.
为准确预警煤炭自然发火,基于程序升温试验,获得指标气体与温度间的关系,并将起始温度V0和特征温度点V1、V2、V3时刻的碳氧化物比率作为预警界限,设定4级预警机制,采用灰色关联分析法关联性分析采空区和上隅角CO气体体积分数和碳氧化物比率,按照关联等级的高低细化4级预警机制,同时选取典型案例,详细展示该预警机制下的预警流...  相似文献   
679.
The sperm cell toxicity test with Paracentrotus lividus is widely used in Italy to assess the quality of complex aqueous matrices, but at present there is a shortage of standardized methodologies for the bioassay performance. In this work several critical points were considered, in order to verify the reliability of this bioassay and to improve its standardization.In particular, we have studied the differences in EC50 values at different sperm: egg ratios and with different quantities of gametes; the influence of sperm and eggs on fertilization rate and the influence of different recipients materials (plastic or glass). At the same time, it was evaluated if the obtained EC50 values were in accordance with those reported in literature.Experiments performed yielded EC50 values for copper ranging from 16.54 μ g/l to 69.59 μ g/l, with a total mean value ± SD of 39.79 μ g/l ± 11.17. These data fit with those found in literature for other echinoid species. According to the same authors, poor fertilization was probably due to the effects on sperm and not on eggs, and moreover the linear regression analysis performed on each experiment suggested that the best amount of eggs to use in the test was 1000.Results from the comparison between the performance of the test in plastic or glass tubes showed an higher success in fertilization rate using borosilicate glass tubes.  相似文献   
680.
汽车模拟日照太阳辐射试验设备研制   总被引:1,自引:0,他引:1  
本文根据汽车整车太阳辐射试验的要求,介绍了自主设计的基于红外线灯泡阵列的无紫外线汽车模拟太阳辐射试验设备的总体方案,并重点讨论了在光源、电气控制等各方面的设计思路及具体实现过程。  相似文献   
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