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781.
我国农村养老模式的绩效研究 总被引:2,自引:0,他引:2
继新农合实施以来,新农保也被党和政府提上日程。认识现有养老模式的优缺点是有效开展新农合的前提。本文将现有各种养老模式总结为三种理论模式,分别是个体时间平衡、家庭时间平衡、社会时间平衡。然后在回顾各模式的历史演变的基础上,从理论上对比了三者之间的绩效差异,绩效研究的视角有风险化解的有效性、个体福利和社会福利三个。研究结果表明,风险化解最为有效的是社会时间平衡,其次是家庭时间平衡,最后个体时间平衡;从个体福利的角度来看,个体福利最大的是家庭时间平衡、其次是社会时间平衡,再者是个体时间平衡;从社会福利的角度来看,个体时间平衡和家庭时间平衡是能够促进经济的长期增长的,而社会时间平衡方式则不利于资本积累,相反有可能妨碍经济的长期增长。 相似文献
782.
湿法脱硫石灰石制浆系统的比选 总被引:1,自引:1,他引:0
石灰石制浆系统被广泛应用于燃煤电厂石灰石/石膏湿法烟气脱硫系统中。对典型的湿磨制浆和石灰石粉制浆系统从工艺流程特点、设备组成、技术经济等方面进行详细的分析比较。考虑到1000MW机组工程石灰石耗量较大,从电厂长期运行角度考虑,推荐采用技术成熟、运行经济的石灰石湿磨制浆方案,同时要加强湿磨制浆系统的日常维护和管理: 相似文献
783.
安全检查是现代安全管理中最有效的手段 ,也是企业发现事故隐患、促进现场安全文明生产的好途径。介绍了安全检查作用及特性 ,并结合目前安全检查存在的不足 ,提出了一些强化安全检查效果的对策。 相似文献
784.
The octanol/water partition coefficients (P ow) of six monoisocyanate and five diisocyanate compounds were determined by high performance liquid chromatograph (HPLC) methods. Two HPLC peaks, a broad tailed peak followed by a sharp one, were observed with all compounds. The later peak was identified as the isocyanate compound. The P ow value for each isocyanate compound was determined by fitting the capacity factor of the peak to the regression equation drawn from those of reference compounds. The hydrophobic substituent constants for the isocyanate group were calculated with each of the compounds. The value of this constant was strongly dependent on the type of carbon bound to the isocyanate group and the average values for the aromatic and aliphatic isocyanate groups were 0.35 and — 0.52, respectively. Because of the reactivity of those compounds in the aquatic environment, the P ow has little relevance to calculation of their environmental fate and ecotoxicity. 相似文献
785.
一种新的飞行事故征候率监视与控制方法 总被引:1,自引:1,他引:0
杜毅 《中国安全科学学报》2010,20(10)
为了改进民用航空飞行安全的监控手段,探讨了一种飞行事故征候率的监视和控制方法。通过采用W检验法,对中国民航2008年各月飞行事故征候率统计数据进行正态分布拟合优度检验。结果表明:在10%的显著水平下,飞行事故征候率总体服从正态分布。假设正常情况下,飞行事故征候率超过警戒值的概率仅为0.1%,选择该概率为确定警戒值的标准。根据前一年12个月的飞行事故征候率统计数据和确定警戒值的标准,以子样均值作为母体均值估计量,子样无偏方差的平方根作为母体标准差的估计量,可计算出当年飞行事故征候率警戒值;此外,还提出了控制民用航空安全水平的准则。 相似文献
786.
中国的自然保护地具有生态和文化双重价值,文化景观作为自然与文化的交界面,如何识别其价值对中国自然保护地的管理至关重要。以泰山为例,通过古籍文献和实地勘察等方法,从历时性角度对泰山的文化景观价值演变进行剖析。研究发现,泰山文化景观价值经历了山岳崇拜的自然价值、君权神授的政治价值、佛道信仰的宗教价值、祭祀游居的民俗价值及保护利用的综合价值五个阶段。结论认为:自然保护地文化景观价值的演变具有一定的规律性:名山自然保护地的文化景观价值演变是从自然到文化再到综合、从御到民、从单一到多元、从分离到融合的过程;自然保护地文化景观价值的构成要素包括思想基础、环境条件、行为方式及空间结果四部分,具有鲜明的完整性、系统性和动态性特征。文章还对自然保护地文化景观价值的识别策略进行了讨论,为相应类型的国家公园和其他类型自然保护地建设提供参考。 相似文献
787.
Dimitrios Komilis Konstantinos Kissas Avraam Symeonidis 《Waste management (New York, N.Y.)》2014,34(2):249-255
Objective of the work was to experimentally determine the effect of the organic matter and moisture contents on the calorific value of organic solid wastes. Nine substrates (i.e. newsprint, biodried municipal solid wastes, municipal solid waste derived composts, wastewater sludges, and sea weed derived compost), with organic matter contents that ranged from 12% to 91% (dry weight) were used in the experiments. All substrates were dried and ground and deionized water was artificially added in order to achieve certain target moisture contents per substrate. The higher heating value (HHV) was, then, determined experimentally for each sample using a bomb calorimeter. Best reduced models were developed to describe the higher and lower heating values as a function of organic matter, ash and moisture contents. A triangular plot was constructed and the self-sustained combustion area was determined and compared to that of the Tanner diagram. Response surfaces were drawn to visually assess the effect of organic matter and moisture contents on the calorific value of the wastes. 相似文献
788.
789.
Policies for conservation outside protected areas, such as those designed to address the decline in Australian mammals, will not result in net improvements unless they address barriers to proenvironmental behavior. We used a mixed‐methods approach to explore potential value‐action gaps (disconnects between values and subsequent action) for small mammal conservation behaviors among pastoralists in dryland Australia. Using semistructured surveys and open‐ended interviews (n = 43), we explored values toward small mammals; uptake of a range of current and intended actions that may provide benefit to small mammals; and potential perceived barriers to their uptake. Pastoralists assigned great conservation value to small mammals; over 80% (n = 36) agreed to strongly agreed that small mammals on their property were important. These values did not translate into stated willingness to engage in voluntary cessation of wild‐dog control (r2 = 0.187, p = 0.142, n = 43). However, assigning great conservation value to small mammals was strongly related to stated voluntary willingness to engage in the proenvironmental behavior most likely to result in benefits to small mammals: cat and fox control (r2 = 0.558, p = 0.000, n = 43). There was no significant difference between stated voluntarily and incentivized willingness to engage in cat and fox control (p = 0.862, n = 43). The high levels of willingness to engage in voluntary cat and fox control highlight a potential entry point for addressing Australia's mammal declines because the engagement of pastoralists in conservation programs targeting cat and fox control is unlikely to be prevented by attitudinal constraints. Qualitative data suggest there is likely a subpopulation of pastoralists who value small mammals but do not wish to engage in formal conservation programs due to relational barriers with potential implementers. A long‐term commitment to engagement with pastoralists by implementers will thus be necessary for conservation success. On‐property cat and fox control programs that build and leverage trust, shared goals, collaboration, and shared learning experiences between stakeholders and that explicitly recognize the complexity of small mammal dynamics and the property‐level ecological knowledge of pastoralists are more likely to gain traction. 相似文献
790.
Abstract: The economic valuation of ecosystem services is a key policy tool in stemming losses of biological diversity. It is proposed that the loss of ecosystem function and the biological resources within ecosystems is due in part to the failure of markets to recognize the benefits humans derive from ecosystems. Placing monetary values on ecosystem services is often suggested as a necessary step in correcting such market failures. We consider the effects of valuing different types of ecosystem services within an economic framework. We argue that provisioning and regulating ecosystem services are generally produced and consumed in ways that make them amenable to economic valuation. The values associated with cultural ecosystem services lie outside the domain of economic valuation, but their worth may be expressed through noneconomic, deliberative forms of valuation. We argue that supporting ecosystem services are not of direct value and that the losses of such services can be expressed in terms of the effects of their loss on the risk to the provision of the directly valued ecosystem services they support. We propose a heuristic framework that considers the relations between ecological risks and returns in the provision of ecosystem services. The proposed ecosystem‐service valuation framework, which allows the expression of the value of all types of ecosystem services, calls for a shift from static, purely monetary valuation toward the consideration of trade‐offs between the current flow of benefits from ecosystems and the ability of those ecosystems to provide future flows. 相似文献