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81.
Research on policy support or public acceptability of climate change policies is proliferating. There is, however, a great diversity in how these evaluative responses have been defined, operationalized, and measured across studies. In order to shed some light on this subject, we reviewed 118 studies published over the last 15 years aiming at measurement of policy acceptability, acceptance, support, and other responses to climate change mitigation policies. We found that conceptual vagueness and weak theoretical embedding are pervasive in the field, which leads to uncertainty over what is being measured, ambiguity of policy recommendations, and difficulties in comparing empirical results. In response, we propose a construct of policy attitudes as an overarching concept comprising the diversity of measures and constructs already in use. The purpose of the construct is to serve as a common basis for operationalization and survey design. In order to inform policy makers, researchers should be clear in how they formulate surveys with a focus on questions of importance to research and policy-making.

Key policy insights

  • Acceptability, acceptance, and support are defined as distinct and possibly empirically distinguishable classes of responses evaluating a policy proposal. These responses are expressions of underlying policy attitudes.

  • People may respond to policies in other ways as well, including lack of interest.

  • There is no popularity threshold for a policy to be safe to implement, but instead it is a matter of identifying the conditions of policy support or other responses.

  • Results obtained using different measures of mitigation policy attitudes vary widely with respect to the characteristics of the policy in question and the measured response. Thus, great care must be taken when designing surveys and interpreting their results.

  相似文献   
82.
对强渗透性地层旋挖钻进成孔混凝土灌注桩质量通病进行了分析,总结此类地层必须重视泥浆护壁质量对混凝土灌注桩施工质量的重大影响,必须重视钻斗的活塞抽吸对孔壁的破坏性,建议其验收标准中增加泥浆护壁质量验收,重视清孔后的孔径验收,不可完全沿用与旋挖钻孔泥浆护壁效果有着天壤区别的回转钻、潜水钻成孔混凝土灌注桩的质量验收标准。  相似文献   
83.
中国东部大规模成矿时限及其动力学背景的初步探讨   总被引:93,自引:24,他引:93  
毛景文  王志良 《矿床地质》2000,19(4):289-296
通过对以往金属矿床同位素年龄数据的收集、整理和分析 ,初步厘定中国东部大规模成矿作用发生的时限为 1 60× 1 0 6~ 1 1 0× 1 0 6 a。提出西秦岭地区金矿床出现于中国两大古陆后碰撞的伸展环境 ;与花岗岩有关的铜钼矿床发育于早中侏罗世由挤压向伸展环境过渡时期 ,钨锡铅锌银锑汞金铀出现于晚侏罗世—早中白垩世岩石圈大规模拆沉或减薄期间。尽管不同类型矿床形成过程有所不同 ,都与大规模构造圈热侵蚀密切相关。  相似文献   
84.
Soils containing expansive clays undergo swelling that can be both detrimental and beneficial in various applications. In the Arabian Gulf coastal region, natural heterogeneous soils containing clay and sand (tills, shales, and clayey sands) support most of the civil infrastructure systems. Likewise, mixes of clay and sand are used for local earthwork construction such as roads and landfills. A clear understanding of the swelling behaviour of such soils is pivotal at the outset of all construction projects. The main objective of this paper was to understand the evolution of swelling with increasing clay content in local soils. A theoretical framework for clay–sand soils was developed using phase relationships. Laboratory investigations comprised of mineralogical composition and geotechnical index properties of the clay and sand and consistency limits, swelling potential, and morphology of clay–sand mixes. Results indicated that soil consistency of mixes of a local expansive clay and an engineered sand depends on the weighted average of the constituents. Mixes with 10% clay through 40% clay capture the transition from a sand-like behaviour to a clay-like behaviour. Influenced by the initial conditions and soil matrix, the swelling potential of the investigated mixes correlated well with soil plasticity (SP(%) = 0.16 (I p)1.188). The parameters sand void ratio and clay–water ratio were found to better explain the behaviour of blended clay–sand soils.  相似文献   
85.
苏里格气田东区盒8层段属致密砂岩层,具有低孔低渗的特点。采用经验统计法、孔隙度—渗透率交会法、岩芯饱和度分析法、最小孔喉半径法、有效孔隙百分含量法、相渗分析法和试气法等7种方法综合分析,确定了苏东地区盒8层段孔隙度和渗透率下限值分别为4.7%和0.08×10-3μm2,并运用试气结论和试气产量证明了储层物性下限值的合理性。  相似文献   
86.
三峡工程建基面岩体弹性波检测技术   总被引:2,自引:0,他引:2  
长江三峡水利枢纽是一个举世瞩目的世纪性工程,它的开工建设,标志着我国水电事业的成熟与发展。三峡工程规模巨大,技术复杂,设计单位针对该枢纽各建筑物的特点,提出了工程建设质量标准及技术要求,而这些要求在某些方面高于国家及部颁规范和标准,三峡工程建基面岩体弹性波检测技术即是其中之一。它利用完整岩体与缺陷岩体的物性差异,采用与建基面平行和垂直两个方向的弹性波观测方式,评价建基面岩体一定深度(一般为5m)范围内岩体的完整性情况,从而为枢纽基础开挖验收提供了岩体定量物性依据。三峡枢纽建基面岩体弹性波检测技术全面覆盖了基础开挖工程,历时八年,这在中国水电建设史乃至世界水电建设史上都是绝无仅有的。同时,也大大促进了用弹性波方法评价岩体质量技术的进步。由于是第一次将弹性波检测技术大范围地应用于水电工程基础验收工作中,从建基面岩体弹性波检测技术要求、检测基本理论及方法技术、典型成果分析等方面,介绍了该项技术在三峡工程中的应用和效果。作为水电工程基础验收新方法的初步总结,抛砖引玉,以求方法的完善,更好地运用于工程建设,为国民经济建设服务。  相似文献   
87.
针对现有巷道建模方法中存在的岔道口处模型不平滑或不连通,以及模型难以达到工程验收标准的问题,提出一种基于实测数据的巷道系统三维自动建模方法。根据实测导线中的定位数据特点,采用红黑树存储定位数据,实现巷道系统关联数据的分层快速搜索;由测点数据生成中心线,保证巷道模型能够有效反映工程的实际情况;对交岔口处模型进行布尔运算,实现巷道间的平滑连通。采用VS2008和HOOPS可视化工具包实现该方法,实验结果表明该方法能够快速重构出地下巷道三维模型,为矿山巷道工程验收等提供准确的数据来源。  相似文献   
88.
航道疏浚工程竣工验收数字化测量技术研究   总被引:1,自引:0,他引:1  
根据航道疏浚工程竣工验收数字化测量作业流程,阐述了航道疏浚工程竣工验收测量方法和技巧,并借助测量成图软件CASS,绘制航道疏浚工程竣工图,并对绘制过程中的相关技术问题进行了探讨。  相似文献   
89.
采用软件ABAQUS对钢筋混凝土梁进行有限元模拟,即可获取梁的荷载-位移骨架曲线。将试验结果和模拟结果进行对比,结果表明,有限元可以较准确地模拟试验情况。然后同样采用软件ABAQUS来模拟146根梁,并获取该批梁的弯矩-转角骨架曲线。将曲线按照不同因素进行分类,并由这些曲线得出梁的性能参数:塑性转角限值。塑性转角限值能为梁的性能评估提供定量的参考指标。  相似文献   
90.
In this paper, we discuss the theoretical relationships among interacting global change risks, valued livelihood goals, and adaptation limits. We build from research on the impacts of multiple and interacting global change risks in lesser-developed countries and seek to understand household adaptation limits in agrarian communities. We ask: What are valued livelihood goals among smallholder farmers in Northwest Costa Rica? How do socio-economic determinants of adaptive capacities determine their ability to meet these goals in the face of the impacts of interacting global change risks? Our data were based on focus groups, interviews, survey responses from 94 smallholder farmers, government statistics, and published literature. We analyzed our data using qualitative content analysis and quantitative logistic regression models. Our analysis showed that farmers perceived rice production as an identity, and that they were being forced to consider limits to their abilities to adapt to maintain that identity. We found that farm size, cattle ownership, years spent farming, and household income variety were determinants of their abilities to remain in rice production while maintaining sufficient levels of livelihood security. We also showed that for those households most vulnerable to water scarcity, their ability to successfully adapt to meet valued livelihood goals is diminished because adaptation to water scarcity increases vulnerability to decreased rice-market access. In this way, they become trapped by the inability to reduce their vulnerability to risks of the interaction between global changes and therefore abandon valued identities and livelihoods.  相似文献   
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