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761.
The effort to transition energy sources away from dependence on fossil fuels has become highly divided along partisan lines in some countries, but the social-science literature has not yet caught up with this important problem. Policy-adoption studies do not address the specific problem of polarization and gridlock, and the literature on gridlock does not examine conditions for breaking gridlock for renewable energy and energy efficiency (REEE) policy. Qualitative research can help to fill the void by identifying strategies that legislators use for achieving support for REEE policy where there is gridlock, polarization, and/or strong opposition. Interview data from a stratified sample of US states reveals three strategies that state-government legislators use to enhance REEE policy development under these conditions: bring to the process countervailing industrial interests to align REEE with business; transfer decision making to public service commissions; and use extra-legislative consultation processes to develop stakeholder consensus.  相似文献   
762.
    
Seas and oceans are confronted with a plethora of environmental problems, caused by land-based activities (agriculture, industries, and ports) and by maritime activities (such as shipping, fishing, oil and gas drilling, tourism, and navigational dredging). Environmental problems at sea challenge the efficacy of state sovereignty. Who is responsible, accountable, and regulates environmental and spatial problems at the level of regional seas, and what is the role of states in these processes of governance? In the regional seas and on the high seas, the environmental state is challenged by two developments: states become players at different levels, and states are confronted with the activities of big market players where they have no or little jurisdiction. The different forms of the environmental state in Europe’s regional seas and in the Arctic Ocean are examined.  相似文献   
763.
    
Morphometric characteristics of the growth of forest stands located at different distances from a large copper-smelting plant were estimated. The set of diagnostic parameters obtained was used for calculating summary parameters of the state (SPSs) of the forest stands and to grade their values for zoning the forests. The results of using semivariance analysis demonstrated the appropriateness of kriging, a method of spatial interpolation, for mapping the surfaces of the state of forests. The map-scheme of the zones differing in the state of forest stands (made on the basis of summary parameters) was compared with the topographic map of the area, which made it possible to estimate the effect of large forms of relief on the location and configuration of the zones.  相似文献   
764.
海洋平台造价昂贵,所处的海洋环境复杂且恶劣,受到波浪、流、风、冰、地震以及疲劳、腐蚀、冲刷等时变因素的联合作用,检测和维修困难,事故后果严重,所以,为延长在役导管架平台的寿命而进行的评估研究存在许多难题需要解决。针对近海导管架平台评估标准、检测策略、构件校核、系统分析、维修加固决策和方法等,介绍了国内外的研究现状,并展望了将来需要进一步开展的工作。  相似文献   
765.
火灾下建筑结构抗火性能和人员疏散问题是建筑火灾科学的两个重要研究内容,尽管二者最为关注的目标都与时间有关,即结构耐火时间和疏散时间,但实际对这两个问题的研究基本上是独立进行的。首先对结构抗火性能和人员疏散的研究现状和存在的问题进行了梳理总结,从疏散范围和疏散时间两方面讨论了结构抗火性能和人员疏散之间需要满足的关系。基于此,提出了一种适合于性能化结构抗火设计新的极限状态——安全疏散极限状态,将结构抗火性能研究和人员安全疏散结合起来,进而利用时间变量建立极限状态方程,为性能化结构抗火设计提供了一种新的思路。最后,对未来需要解决的若干关键问题进行展望。  相似文献   
766.
针对 2011 年 6 月 3 日,因用户侧 35 kV 开关柜发生三相短路,导致石嘴山供电局220 kV步桥变电站4号主变压器差动保护和重瓦斯保护相继动作,主变压器三侧开关切除的故障,对绝缘油色谱、绕组直流电阻、电压比、频响法绕组变形及低压短路阻抗测试结果进行综合分析。结果表明:该变压器内部发生了严重的放电性故障,中、低压侧绕组均发生了变形和匝间短路,且低压绕组三相绕组出现了严重的断股。  相似文献   
767.
重力式挡土墙整体稳定性检算最不利状态选取对抗震设计有重要影响。针对加速度峰值、墙身外倾峰值、墙顶位移峰值三种典型挡墙抗震危险时刻以及常用“土压力峰值时刻包络”取值方法,以振动台模型试验揭示地震土压力取值结果差异性,基于重力式挡土墙ABAQUS 有限元模型地震响应计算,分析各危险时刻墙背土压力取值及整体稳定性检算结果差异,提出抗震稳定性检算最不利状态建议。结果表明:(1)随地面峰值加速度和墙高增加,三种危险时刻地震土压力均呈现从非线性分布向近似正三角图式转化,合力及作用点高度整体上较现行抗震规范分别大49% 和18%;(2)峰值包络法因不能反映墙-土运动主/被动状态和地震动传导时延特征,致使墙顶附近土压力取值结果过大,地震土压力合力较危险时刻大一倍且作用点偏高约25%;(3)墙身外倾峰值危险时刻的抗滑移稳定系数较其余两种危险时刻偏小14%~33%,且随地面峰值加速度增大反映出更明显的衰减敏感性,以此作为抗震稳定性检算最不利状态有利于结构安全与经济性协调。  相似文献   
768.
国际GPS服务机构(IGS)的现状与最新进展   总被引:1,自引:0,他引:1  
介绍了国际GPS服务(IGS)机构的宗旨、现状和已取得的成果以及最新进展。IGS的数据和成果主要用于全球范围内多学科的科学研究,本介绍将有利于加强与IGS的合作,充分利用国际GPS服务机构的成果,促进我国地震监测预报和减灾科学研究更快的发展。  相似文献   
769.
In order to understand the residue levels of organochlorine compounds (OCs) and their accumulation patterns in wildlife inhabiting Chubu region, Japan, the concentrations of polychlorinated biphenyls (PCBs), hexachlorocyclohexane isomers (HCHs), DDT compounds (DDTs) and hexachlorobenzene (HCB) were measured in 8 species of terrestrial mammals and 10 species of birds. In view of feeding habits, the contamination levels of OCs were found to be higher in omnivorous mammals than in herbivorous ones, and in fish-eating ones and raptores than in omnivorous birds. In fox and dog, PCB-180 (2, 2′, 3, 4, 4′, 5, 5′-heptachlorobiphenyl) was the most dominant PCB congener, while in the other species PCB-153 (2, 2′, 4, 4′, 5, 5′-hexachlorobiphenyl) was the most persistent. The ratios of lower chlorinated PCB congeners (tri- to tetra-) to total PCBs were larger in fish-eating birds than in the other birds. The results indicate that the compositions of PCB congeners would reflect the differences of feeding habits and xenobiotic metabolizing systems among each species.  相似文献   
770.
    
Recently, new approaches to wildlife management are being developed, such as coexistence management and convivial conservation. These approaches aim to shift management practices from mitigating human–wildlife conflicts towards cohabitation and explore mutual benefits. To align empirical research to these new approaches, we argue for the relevance of positive psychology theory to inspire and structure research into the benefits of human–wildlife interactions. Positive psychology suggests three pathways through which human–wildlife interactions may lead to happiness and well-being: pleasure, engagement, and meaning. Applying these pathways to human–wildlife research may (i) structure existing research into the benefits of human–wildlife interactions, (ii) disclose unidentified benefits of human–wildlife interactions, and (iii) unravel mechanisms which make experiencing and protecting wildlife worthwhile and rewarding. Also, we suggest a potential feedback loop between wildlife experiences, happiness and well-being, and pro-environmental behaviours. More in-depth research into these mechanisms may improve our understanding of attitudes towards conservation of wildlife and its habitat and may suggest strategies to strengthen stewardship actions and public support for conservation strategies. Together, these strands of research could initiate research into what could be called a “Positive Ecology”.  相似文献   
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