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81.
ABSTRACT

Objective: This study analyzed the influence of reference sensor inputs from anthropomorphic test devices (ATDs) versus postmortem human subjects (PMHSs) on simulations of frontal blunt impacts to the advanced combat helmet (ACH).

Methods: A rigid-arm pendulum was used to generate frontal impacts to ACHs mounted on ATDs and PMHS. An appropriately sized ACH was selected according to standard fitting guidelines. The National Operating Committee on Standards for Athletic Equipment (NOCSAE) head was selected for ATD tests due to shape features that enabled a realistic helmet fit. A custom procedure was used to mount a reference sensor internally near the center of gravity (CG) of the PMHS. Reference sensor data from the head CG were used as inputs for the Simulated Injury Monitor (SIMon). Brain responses were assessed with the cumulative strain damage measure set at 10%, or CSDM(10).

Results: Compared to ATD tests, PMHS tests produced 18.7% higher peak linear accelerations and 5.2% higher peak angular velocities. Average times to peak for linear accelerations were relatively similar between ATDs (5.5?ms) and PMHSs (5.8?ms). However, times to peak for angular velocities were higher by a factor of up to 3.4 for PMHSs compared to ATDs. Values for were also higher by a factor of up to 13.1 when PMHS inputs were used for SIMon.

Conclusions: The preliminary findings of this work indicate that small differences in ATD versus PMHS head kinematics could lead to large differences in strain-derived brain injury metrics such as CSDM.  相似文献   
82.
通过对几起环境行政违法行为中违法主体认定的案例分析,指出,随着市场经济的发展,企业的经济行为日趋复杂,企业环境管理模式日渐多样化,对环境行政违法行为中违法主体的认定,必须以事实为依据,以法律为准绳。  相似文献   
83.
当前有关流域生态补偿的研究和实践探索,均倾向于从责任分配视角来设定流域生态补偿的适用条件。然而,从责任分配视角来界定流域生态补偿之适用条件面临着诸多困境。以水质控制目标作为适用条件的地方立法和以超过Ⅲ类水质标准作为流域生态补偿适用条件之观点,均限缩了流域生态补偿的适用范围,导致了补偿义务主体与受偿主体之间法律关系的混乱,并背离了流域生态补偿的本质和基本功能预设。无论从流域生态补偿的功能定位出发,还是基于该制度构建的正当性基础和可行性考量,均应从权利确认而非责任分配视角来明晰流域生态补偿之适用条件。首先,流域生态补偿的基本功能是流域生态利益正向供给激励,受偿主体的权利确认与保障是这一制度构建的重心。从责任分配的角度来界定流域生态补偿之适用条件,将导致其基本功能的偏离;其次,"最少受惠者的最大利益"原则是流域生态补偿制度构建的正当性基础,流域生态补偿的本质是对"最少受惠者"发展权的弥补。从责任分配视角界定流域生态补偿之适用条件遮蔽了流域生态补偿法律关系中的"最少受惠者";再次,受益主体的非特定性意味着从权利确认视角来界定流域生态补偿之适用条件将更具有可行性。从权利确认视角来看,流域生态补偿的适用条件应包括:有生态增益行为、非有责主体、不问主观动机与现实损害后果。  相似文献   
84.
Collentine, Dennis and Holger Johnsson, 2011. Crop Discharge Permits for Reduction of Nitrogen Loads to the Baltic Sea. Journal of the American Water Resources Association (JAWRA) 48(1): 24‐31. DOI: 10.1111/j.1752‐1688.2011.00596.x Abstract: Current international agreements call for a significant reduction of nutrient loads to the Baltic Sea. In one of the signatory countries, Sweden, regulatory authorities have concluded that new measures will be needed to meet national reduction targets. This article evaluates the effect of one possible new measure for reducing nitrogen loads, introducing mandatory discharge permits for crop cultivation as one component of a proposed discharge permit system. Using the framework of the proposed system, expected net load reductions and permit prices are calculated for three crop permit scenarios in a catchment in Southern Sweden. In addition, gross leaching is calculated for a larger region to study the potential for reducing net loads. The article concludes that while permitting reduces loading, achieving reduction targets will require additional measures beyond the scenarios studied.  相似文献   
85.
排污权的合理定价可以为环境保护提供正确的经济激励,引导排污企业将污染排放量设定在社会的最优水平。从理论上分析了排污权定价时应综合考虑的影响因素,构建了排污权定价模型的指标体系;运用主成分分析法和客观赋值法,从地区因素、污染物因素和行业因素3方面附加权重计算排污权基准价定价模型的价格系数,为排污权合理定价提供参考。  相似文献   
86.
回顾安全投资理论的发展历程,分析研究现状,归纳相关研究文献,指出理论研究方面主要存在的"安全投资决策评价方法亟待创新;安全投资评价方法忽略了外部竞争性、未来不确定性、不可逆性、长期性和潜在性等因素;实物期权博弈理论还未形成完整的体系"3个问题。提出解决问题的对策:给出安全投资战略期权博弈分析的思路,建立不确定条件下安全投资战略项目的价值模型,概括出安全投资战略实物期权博弈分析的理论框架以及理论依据、分析工具和分析步骤。指出了安全投资理论的研究趋势。基于实物期权博弈的安全投资决策,使安全投资项目的管理柔性价值和战略价值得到准确的衡量。  相似文献   
87.
突出行业特点的安全工程专业教育研究   总被引:6,自引:2,他引:4  
以我国安全工程专业学科建设过程为背景,分析安全工程专业教育存在的学科建设速度快、涉及知识面广、注重通识性教育等现状,结合我国近两年特大安全事故所表现的行业特点,从解决当前我国生产安全问题、培养高层次安全专业人才、促进安全学科发展3个方面入手,阐明安全工程专业教育中突出行业特点,进一步加强该领域安全工程专业教育建设的重要性,针对突出行业特点的安全工程专业教育模式提出了几点建议,特别强调安全科学与安全技术联系与独立的重要性,学科建设结合每个学校自己的特色方向和以点带面的建设及发展模式.  相似文献   
88.
Acceptability and personal outcome expectations (i.e., the extent to which one expects to be better or worse off) of transport pricing policies were examined in relation to the expected effects of these policies on one’s own car use, congestion and environmental problems. Car users who commuted frequently by car and experienced congestion on a regular basis evaluated two pricing measures, which were mainly aimed at either decreasing congestion (by tolling at congested areas) or environmental problems (by a differential kilometre charge based on car mass). For the policy mainly aimed to reduce congestion, acceptability was higher and personal outcome expectations were more positive when respondents expected reductions in congestion when the policy was implemented. The policy aimed to reduce environmental problems was more acceptable and respondents expected to be better off in general when they expected reductions in environmental problems after its implementation. Expectations, both about a decrease in congestion and environmental problems were related to respondents’ personal outcome expectations of the policy mainly aimed to decrease environmental problems. We conclude that the acceptability of transport pricing policies are not necessarily low because car users expect negative effects on their car use, but rather because they are not be convinced that transport pricing policies will reduce congestion and environmental problems.  相似文献   
89.
ABSTRACT

The momentum achieved for unilateral carbon taxes in seven European countries is examined. Why is it that small countries, despite being vulnerable to forces of international competition, have been able to implement carbon taxes? A review of national experiences does not suggest that the share of fossil fuels in the energy mix defines the room for such taxes, or point to a strong role for traditional left-right ideology. Rather, it is deep-seated patterns of national policy styles with neo-corporatist traits, providing a protective device for the open economies of small countries, which condition the introduction of carbon taxes. The associated routines of decision-making offer coordination mechanisms for proactive macroeconomic policies in which carbon taxation can find a place. Parliamentary democracies with proportional representation, as is common in the smaller countries, provide access to government for political parties that pursue carbon taxation. These in turn sensitise larger political parties to climate concerns, as they benefit from institutionalised practices and routines for problem-solving and consensus-seeking.  相似文献   
90.
中国反贫重点由摆脱绝对贫困向全面实施乡村振兴、系统解决相对贫困转变。农地三权分置改革作为农村土地制度改革的重要内容,对于推进乡村振兴战略和实现共同富裕具有重要作用。根据长江中下游地区1038份入户调研数据,使用多群组结构方程模型,探讨了农地三权分置改革对多元主体收入的影响。结果表明:(1)三权分置对家庭农场和资本农场有积极影响,但对传统农户和种田能手造成了不利的影响,尤其是对种田能手。从作用路径上,传统农户和种田能手收入损失的主要原因分别是经营规模萎缩和负向直接效应,而家庭农场和资本农场收入增加依赖的路径是规模扩张。(2)三权分置对务工经商、农业雇工两类主体收入有积极影响,但对赋闲农户的作用并不乐观。从作用路径上,三权分置主要通过劳动力转移和放松流动性约束两条间接路径提高务工经商、农业雇工主体收入,但赋闲农户的间接路径未形成通路。(3)三权分置对各离农主体的收入总效应高于传统农户、种田能手,却低于家庭农场、资本农场,农业经营主体内部的收入差距要远远高于离农主体内部。研究结论对于完善相关制度政策和助力政策顺利实施、保障农户福利和推动共同富裕有指导意义。  相似文献   
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