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101.
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   

102.
为提高塔机作业安全工效,基于视觉心理学、认知心理学理论,利用眼动追踪技术记录驾驶员视觉行为数据,分析和评估塔机驾驶员视觉转移过程的表征参数,结果表明:起重作业过程中驾驶员注视时间长,视知觉资源主要集中于起吊物,保持持续性注意状态,以维持高效起重作业,心理负荷较大;起重作业不同子过程注视时间与瞳孔直径差异较大,在空中平移过程中注意力较为分散,瞳孔直径较小,心理负荷较小。据此,提出了塔机起重作业的人因工效改善方向,为起重作业安全实施提供决策支持。  相似文献   
103.
The Transition movement has experienced remarkable growth in its first decade, yet there remains considerable doubt about its ability to appeal to a diverse audience. To date, few studies have explicitly examined diversity of participation in the movement. Addressing this gap in the literature, a case study is presented of Transition Town Tooting (TTT). Results from a mixed methods approach comprising semi-structured interviews, participant observation, and a quantitative survey indicate that the demographic profiles of TTT participants do not represent the diversity of the Tooting population. This disparity is exacerbated by TTT’s ‘passive’ approach to inclusivity within the core group. Reflecting upon the implications for Transition’s goal of local resilience, it is suggested that, particularly within dense urban communities, initiatives may have more potential for engaging diverse voices through a local ‘brokering’ role between various subcommunities.  相似文献   
104.
西子生态农场的综合开发利用研究   总被引:8,自引:0,他引:8  
介绍了西子生态农场建设的情况。农场采用德国引进的固液分离技术处理畜禽粪便,制取沼气,沼气发电用于整个农场。沼液,沼渣得到综合利用、整个农场实现污水循环使用,取得了良好的经济效益。,社会效益和生态效益,具有推广价值。  相似文献   
105.
检规TSG T7001-2009第2号修改单新增了对轿厢意外移动保护装置的检验要求,其中对检测子系统的检验理解存在着一定的争议.本文从轿厢意外移动保护装置的设置和组成出发,结合相关检验案例和标准要求探讨了对轿厢意外移动保护装置检验要求的理解,最后对轿厢意外移动保护装置的检验方法进行了分析,并提出了检验方面的建议.  相似文献   
106.
In science and environmental studies, there is a general concern for the democratization of the expert-lay interplay. However, the democratization of expertise does not necessarily lead to more sustainable decisions. If citizens do not take the sustainable choice, what should experts and decision makers do? Should the expert-lay interplay be dissolved? In thinking about how to shape the expert-lay interplay in a better way in agro-biodiversity conservation, I take the case of the MST (Movimento Sem Terra/Landless People’s Movement), possibly the largest rural movement in Latin America. The MST is in a process of turning towards environmentalism. It has adopted agroecology, a democratically oriented knowledge field. However, not all of the farmers were willing to adopt new environmentalist ideas and practices. Through ethnographic research, I analyze how expertise was recognized and redistributed within the MST, attending particularly to the role of MST coordinators and technicians. I explore how participation was framed and put into action. The adoption of agroecology brought to the MST a new and more inclusive map of expertise, but it also influenced new social distinctions within the communities. In part, farmers’ knowledge was labeled as ignorance. This may close down possibilities for dialogue as well as for sustainability. The paper suggests that experts’ power for discriminating among lay knowledges should come together with a responsibility for opening spaces for dialogue and action. One way of doing so could be by adding “interactional reflexivity” to experts’ expertise.  相似文献   
107.
河道污染质垂向迁移对地下水影响的研究   总被引:5,自引:1,他引:4  
包气带是连接地表水和地下水的重要通道,对地下水资源有很好的"屏障"功能,而近年来工农业废水及生活污水的大量排放已影响到了地下水的"安全".为此,在渭河河漫滩进行了模拟河流的垂向入渗试验,并通过建立数学模型对水分和六价铬在具有弱透水层的多层介质中的迁移进行了模拟运算.试验和模拟结果一致表明,弱透水层虽对地下水有很好的保护作用,但在上部土壤层易形成面状污染带,而且由于大的浓度梯度作用,一旦污染质穿透该层将很快污染到地下水.  相似文献   
108.
Although the notion of natural behavior occurs in many policy-making and legal documents on animal welfare, no consensus has been reached concerning its definition. This paper argues that one reason why the notion resists unanimously accepted definition is that natural behavior is not properly a biological concept, although it aspires to be one, but rather a philosophical tendency to perceive animal behavior in accordance with certain dichotomies between nature and culture, animal and human, original orders and invented artifacts. The paper scrutinizes the philosophy of natural behavior as it developed in the organic movement in response to a perceived contrast between industrialized and traditional agriculture. There are two reasons for focusing on the organic movement: (i) the emphasis on “the natural” is most accentuated there and has a long history, (ii) everyday life on organic farms presupposes human/animal interplay, which conflicts with the philosophical tendency to separate nature from culture. This mismatch between theory and practice helps us see why, and how, the philosophy of natural behavior needs to be reconsidered. The paper proposes that we understand farms as local human/animal cultures, and asks what we can mean my natural behavior in such contexts. Since domestic animals adapt to agricultural environments via interaction with caretakers, such interplay is analyzed as “hub” in these animals’ natural behavior.  相似文献   
109.
白思胜  张佐堂 《灾害学》2006,21(3):85-88
目前,地震和地震带的成因问题仍然是世界性的科学难题。本研究认为圈闭隐爆作用能形成正楔块、倒楔块;负荷均衡作用能引起楔块运动;楔块运动形成了断陷盆地,也就是说,地堑、地垒是楔块运动的产物;最终,试图通过对楔块运动模式的研究揭示地壳凹陷与地震带的成因问题。  相似文献   
110.
Public debate on acceptable farm animal husbandry suffers from a confusion of tongues. To clarify positions of various stakeholder groups in their joint search for acceptable solutions, the concept of animal welfare was split up into three notions: no suffering, respect for intrinsic value, and non-appalling appearance of animals. This strategy was based on the hypothesis that multi-stakeholder solutions should be based on shared values rather than on compromises. The usefulness of such an artificial value distinction strategy was tested in a small series of experiments. The results demonstrate that the chosen concept to distinguish between values is effective in a stakeholder context. Farmers’ views on doing good to animals appeared to be largely based on their value to prevent suffering and predominantly focused on the provision of regular care. Their priority for this value is clearly shared with other stakeholders, providing a basis for joint solutions. The concept of intrinsic value does not play a discernable role in farmers’ considerations. Based on the varying views on welfare, it can be inferred that there is a gradual rather than a principal difference between government legislation and farmers’ values, whereas public perception and acceptance of farm practices remains complicated. Distinction between value groups and focusing on a selected notion (such as no suffering) proved to be effective in bringing representatives of stakeholder groups together, but is unlikely to bridge the emotional gap between commercial farm practices and public ideals.  相似文献   
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