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381.
Translocation is used to reestablish wild populations of animals, but translocation projects often do not meet their objectives because postrelease mortality of animals is high. One reason for translocation failure is that the behavioral or ecological requirements of released animals are unmet. Maintaining founder-group social relationships during release can affect reestablishment of social species. Solitary territorial species with stable neighbors (restricted dispersal and lifetime occupation of a home range) of the same species may also benefit from the maintenance of these social relationships during translocation. We translocated Stephens' kangaroo rats (Dipodomys stephensi), a solitary species listed as endangered under the U.S. Endangered Species Act, with and without neighboring kangaroo rats. We compared the settlement (establishment of a stable home range) decisions and fitness of kangaroo rats between the 2 treatments. Kangaroo rats translocated with neighbors traveled shorter distances before establishing territories, had higher survival rates, and had significantly higher reproductive success than kangaroo rats translocated without neighbors. Number of offspring was 24-fold higher for kangaroo rats translocated with neighbors than those translocated without neighbors. Differences in behavior following release may partially explain differences in survival between the 2 groups. Immediately following release, animals translocated with neighbors fought less and spent significantly more time foraging and digging burrows than animals translocated without neighbors. Our results indicate that even for solitary species, maintaining relationships among members of a translocated group of animals can influence translocation success. This study is the first empirical demonstration of the fitness consequences of disrupting social relationships among territorial neighbors.  相似文献   
382.
选取条形、L形、T形和环形走廊4种典型建筑结构为研究对象,使用火灾模拟软件FDS对4种典型结构的走廊发生火灾时的烟气流动规律进行了分析。初步得出建筑结构对于火灾烟气的流动和温度分布的影响:对于有封闭转角处的L形和环形走廊,转角处受到建筑封闭结构的阻碍和反浮力作用,热烟气易积聚;而无论何种形式的走廊,都会由于壁面限制和反浮力作用造成走廊末端热烟气的积聚;T形走廊交叉口处流通性较好,相对安全;这些容易造成烟气积聚的走廊转角和走廊末端的温度也会有所上升,而现在很多连接走廊的疏散楼梯都设置在走廊两端,反而不利于人员疏散。因此这些地方应引起重视,加强防火排烟措施。  相似文献   
383.
利用数值模拟方法研究了不同的上游阻挡建筑布局下,行列式和错列式街谷内气流速度和污染物浓度场特征.结果指出,阻挡建筑的存在改变了街谷内的二次流,从而对流场和浓度场均有明显影响.在行列式街谷中,无论上游建筑以何种布局存在,都会减小街谷内污染物浓度.若不考虑上游建筑的存在,将会过高估计行列式街谷内污染程度;在错列式街谷中,与街谷建筑并列的上游阻挡建筑会减小街谷内污染物浓度,而与街谷建筑错列布置的阻挡建筑会增大街谷内污染物浓度;数值模拟结果还表明,街谷内污染物的扩散和清除效果受气流速度和涡流特性的共同作用.  相似文献   
384.
由于受到地下开采扰动的影响,如何保证矿山公路的安全性是研究者们关注的焦点之一。从工程实际出发,基于三维几何建模软件和MIDAS/GTS有限元软件的结合技术,通过建立地表三维模型和矿体三维模型,构建了关于塌陷区沉降模拟的精细三维模型,开展了地下开采过程中临近塌陷区矿山公路沉降特性及其安全性的数值模拟研究。结果表明,随着地下开采强度和范围的增大,地表沉降的规模和程度都在不断增加,临近塌陷区的矿山公路及沿线边坡受到了地下采动的影响也变大;虽然总体仍保持稳定,但是在公路的局部区域存在一定的安全隐患;计算结果和实地调查的情况一致,故得到矿山公路的沉降特性规律为下一步塌陷区的安全有效处治提供了基础数据。  相似文献   
385.
关于高层建筑中几个消防问题的探讨   总被引:4,自引:0,他引:4  
根据目前国内高层建筑的状况,结合所发生的火灾特点,提出了在消防方面应引起重视的几个问题。还给出了处理这些问题的建议和防治方法,并指出在高层建筑中,若所有电梯都设计成消防电梯,同时少建裙房,必将有助于减少火灾造成的损失  相似文献   
386.
This study investigates the strategic antecedents of operational agility in humanitarian logistics. It began by identifying the particular actions to be taken at the strategic level of a humanitarian organisation to support field‐level agility. Next, quantitative data (n=59) were collected on four strategic‐level capabilities (being purposeful, action‐focused, collaborative, and learning‐oriented) and on operational agility (field responsiveness and flexibility). Using a quantitative analysis, the study tested the relationship between organisational capacity building and operational agility and found that the four strategic‐level capabilities are fundamental building blocks of agility. Collectively they account for 52 per cent of the ability of humanitarian logisticians to deal with ongoing changes and disruptions in the field. This study emphasises the need for researchers and practitioners to embrace a broader perspective of agility in humanitarian logistics. In addition, it highlights the inherently strategic nature of agility, the development of which involves focusing simultaneously on multiple drivers.  相似文献   
387.
It is frequently argued that, at the parcel level, 1 stakeholders are capable of and well supported in managing their land‐related risks. Yet, evidence from the contemporary Australian context suggests otherwise: numerous large‐scale disaster events have revealed that citizens are ill‐prepared to respond and recover adequately. This paper begins with the premise that information, specifically land information, could better support parcel‐level risk preparation, mitigation, response, and recovery. State land administration organisations in Australia primarily maintain this information and make it accessible. Land information is used regularly across all levels of government to support risk management activities; however, such application has not always occurred at the parcel and citizen level. Via a case study approach, this paper initially explores the land information available in Australia to stakeholders interested in parcel‐level detail, and then goes on to propose how the utilisation of parcel‐level land information could serve to enhance risk management practices.  相似文献   
388.
As Green Corporate Social Responsibility spreads across the globe, the construction industry is under pressure to reduce the carbon emissions across their building projects. Between maximum profit and environment management, mathematical programming can be used as a decision support tool concerning the optimal green building projects portfolio. This environment strategic decision problem is addressed in this study where an activity-based costing decision model incorporating carbon tax costs and construction resources constraints is developed from the perspectives of capacity expansion and green technology outsourcing. The results illustrate the positive contribution of the mathematical programming approach to achieve viable green building projects portfolio solutions. Sensitivity analyses are carried out to analyse the impact of carbon footprint emission variation on maximum profit, and the corresponding results are discussed.  相似文献   
389.
汶川地震中房屋建筑震害特征及抗震设计思考   总被引:5,自引:0,他引:5  
汶川5·12特大地震造成了为数众多的建筑物不同程度的损坏。地震发生后,四川大学随即组织了现场勘查队奔赴受灾最为严重的地区了解建筑物的受损情况。本文基于大量的现场勘查资料介绍了砌体结构、框架结构、底框或局部底框砌体结构及楼梯间的震害特点。在定性分析的基础上提出以下观点:合理设计和施工的砌体结构有可能获得良好的抗震性能;按现行规范设计的钢筋混凝土框架结构难以实现"强柱弱梁"的要求;填充墙对框架抗震性能有显著的影响;在地震区应慎用底框砌体结构;合理的结构布置和施工质量是结构获得良好抗震性能的前提;仅用延性系数来衡量结构抗震性能具有一定的片面性;楼梯间结构设计宜考虑地震作用的影响。  相似文献   
390.
This paper examines the collapse of a five-storey building in Nairobi, Kenya, on 23 January 2006. It draws on reports from local authorities and on debriefings by Israel's Home Front Command (HFC), including information on injury distribution, rescue techniques, and the mode of operation. Most of the 117 people found under the structure were evacuated on the first day to a public hospital, which was overwhelmed by the incident. HFC forces arrived 23 hours after the disaster. At that stage, two people were still buried under the building and special techniques (tunnelling and scalping) were required to secure their evacuation. The two people quickly recovered after a short stay in hospital. Local technology is the preferred option during such events because time is crucial. International cooperation is required when this technology is not available. All of the hospitals in the disaster area, including private facilities, should participate in treating casualties.  相似文献   
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