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851.
852.
ABSTRACT

The transition to more sustainable energy systems has set about redefining the social roles and responsibilities of citizens. Implicit in this are expectations around participation, though the precise contours of what this might mean remain open. Debates around the energy transition have been skewed towards a normative construct of what it means to be a ‘good citizen’, the parameters for which are shaped by predetermined visions of statist and/or market-driven determinations of the energy systems of the future. This article argues that concepts such as ‘energy citizen’ are co-opted to reflect popular neoliberal discourses, and ignore crucial questions of unequal agency and access to resources. Paradoxically, official discourses that push responsibility for the energy transition onto the ‘citizen-as-consumer’ effectively remove agency from citizens, leaving them largely disconnected and disempowered. Consequently, energy citizenship needs to be reconceptualised to incorporate more collective and inclusive contexts for action. Considering how much energy consumption occurs in (traditionally female) domestic spheres, do conventional notions of citizenship (especially with regards to its associated rights and duties) need to be recalibrated in order for the concept to be usefully applied to the energy transition?  相似文献   
853.
多维地震作用下偏心结构动力反应的Simulink仿真分析   总被引:5,自引:1,他引:5  
理论研究与震害经验表明,地震时结构会产生不可忽略的平动与扭转耦合的空间振动,因此,对结构进行平—扭耦联反应分析具有重要意义。本文首先建立多维地震动作用下偏心结构的空间力学模型和动力方程,并编制相应的MAT LAB程序,然后将动力方程所代表的动力学系统用控制理论中的状态空间法予以描述,根据其状态方程在SIMULINK环境下建立仿真分析模型,从而求解动力方程。对一双向水平地震作用下的6层偏心框架结构进行平—扭耦联反应数值仿真分析,得出了一些有益的结论。  相似文献   
854.
As conservation scholars increasingly recognize the critical role of human thought and behavior in determining the persistence of biodiversity across the globe, a growing line of inquiry regarding the validity and comparability of previous applications of core psychological concepts has emerged. Specifically, inconsistent measurement and use of terms, such as attitudes and acceptance, reveal important questions about previous approaches. Given that these concepts differ by definition, yet have been used interchangeably, we explored what drives differences in people's responses when each concept is operationalized in the context of a contested wildlife species, the gray wolf (Canis lupus). To do so, we used data from a 2014 survey of U.S. residents (n = 1287) to test how measures of six concepts (i.e., acceptance, attitudes, benefits, risks, [prior] behavior, and behavioral intentions) often employed in the conservation social sciences were related with a broad set of possible explanatory variables. Despite moderate to strong correlations between all concepts measured (| Pearson's r | = 0.39–0.65, p < 0.001), results revealed considerable variation in their respective relationships with identical explanatory variables. Specifically, although wildlife value orientation (i.e., domination or mutualism) operated fairly consistently across cognitive and behavioral concepts, the relationship between the six concepts and other factors, such as social trust, identification with various interest groups (i.e., hunter, farmer, or rancher, environmentalist, and animal rights advocate), and political ideology (i.e., liberal vs. conservative), varied considerably. Our findings underscore that differences exist in these measures, which could have serious implications for conservationists integrating social science findings in their decision-making processes if they are unaware of the theoretical underpinnings of and distinctions between core psychological concepts.  相似文献   
855.
Fire has shaped ecological communities worldwide for millennia, but impacts of fire on individual species are often poorly understood. We performed a meta-analysis to predict which traits, habitat, or study variables and fire characteristics affect how mammal species respond to fire. We modeled effect sizes of measures of population abundance or occupancy as a function of various combinations of these traits and variables with phylogenetic least squares regression. Nine of 115 modeled species (7.83%) returned statistically significant effect sizes, suggesting most mammals are resilient to fire. The top-ranked model predicted a negative impact of fire on species with lower reproductive rates, regardless of fire type (estimate = –0.68), a positive impact of burrowing in prescribed fires (estimate = 1.46) but not wildfires, and a positive impact of average fire return interval for wildfires (estimate = 0.93) but not prescribed fires. If a species’ International Union for Conservation of Nature Red List assessment includes fire as a known or possible threat, the species was predicted to respond negatively to wildfire relative to prescribed fire (estimate = –2.84). These findings provide evidence of experts’ abilities to predict whether fire is a threat to a mammal species and the ability of managers to meet the needs of fire-threatened species through prescribed fire. Where empirical data are lacking, our methods provide a basis for predicting mammal responses to fire and thus can guide conservation actions or interventions in species or communities.  相似文献   
856.
Abstract

An experimental study has been made of both the steady‐state and the transient‐phase (presteady‐state) kinetics of the hydrolyses of several saturated aliphatic esters of p‐nitrophenol catalyzed by wheat germ lipase. The analysis of the presteady‐state part revealed two transients indicating that lipase‐catalyzed reactions proceed via a two‐intermediate mechanism suggested for other esterases. The possibility of more than one species of the enzyme engaged in catalytic activity is discussed and a reaction mechanism scheme is proposed accordingly.  相似文献   
857.
中国城市工业污染强度与经济增长耦合关系   总被引:2,自引:0,他引:2  
利用幂函数模型对中国46个重点城市1993-2006年人均GDP和7项工业污染强度指标进行曲线拟合,用于描述和分析我国城市经济发展与工业污染强度的耦合状态,经模型推导提出了“效率弹性系数”,作为度量城市经济与工业污染控制协调发展程度的指标。拟合统计结果显示,中国城市工业污染强度与经济增长的关系曲线形状有明显的幂函数特征。样本城市在“曲线簇”中的位置能揭示“后发优势”以及经济-环境耦合水平优劣的信息。对样本城市效率弹性系数的统计分析证明,该系数可以作为城市经济环境管理的决策依据。  相似文献   
858.
Abstract: Recovery criteria for depleted species or populations normally are based on demographic measures, the goal being to maintain enough individuals over a sufficiently large area to assure a socially tolerable risk of future extinction. Such demographically based recovery criteria may be insufficient to restore the functional roles of strongly interacting species. We explored the idea of developing a recovery criterion for sea otters (Enhydra lutris) in the Aleutian archipelago on the basis of their keystone role in kelp forest ecosystems. We surveyed sea otters and rocky reef habitats at 34 island‐time combinations. The system nearly always existed in either a kelp‐dominated or deforested phase state, which was predictable from sea otter density. We used a resampling analysis of these data to show that the phase state at any particular island can be determined at 95% probability of correct classification with information from as few as six sites. When sea otter population status (and thus the phase state of the kelp forest) was allowed to vary randomly among islands, just 15 islands had to be sampled to estimate the true proportion that were kelp dominated (within 10%) with 90% confidence. We conclude that kelp forest phase state is a more appropriate, sensitive, and cost‐effective measure of sea otter recovery than the more traditional demographically based metrics, and we suggest that similar approaches have broad potential utility in establishing recovery criteria for depleted populations of other functionally important species.  相似文献   
859.
ABSTRACT: Dramatic changes in Utah's economy caused by urbanization, large scale energy developments, and other influences will significantly reorient water use patterns. Thus, state water management policies and programs which have evolved over many years should be reevaluated. Several factors have influenced Utah water project financing policy. Among these have been: 1) the prominence of agriculture in the settlement of Utah and the century following, 2) dry cycles and periodic severe droughts, 3) recurring periods of economic depression, and 4) allocation of Colorado River water among the basin states and Mexico, Three revolving funds have been established. The Revolving Construction Fund, created in 1947, provides money for irrigation projects; the Cities Water Loan Fund, created in 1975, provides money to communities for developing culinary systems and improving quality to meet the demands of exploding population growth; and the Water Resources Conservation and Development Fund, created in 1978, provides money for large scale multipurpose water projects costing $1 million or more. The justification for these financing programs seems to be a mixture of rectifying market imperfections and income redistribution. However, trends in the agricultural sector and the multipurpose nature of large scale projects now being funded suggest that earlier justifications may no longer be valid. Rigorous project evaluation procedures, lacking in the past, should be adopted.  相似文献   
860.
重量法和冷凝法测量烟气含湿量计算公式的改进   总被引:1,自引:0,他引:1  
杨书林 《四川环境》1997,16(2):32-34
本文对现有文献中用重量法和冷凝法测量烟气含湿量的计算公式进行了改进,使改进后的公式更准确、适用。  相似文献   
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