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241.
Conservation auctions for payment for ecosystem services (PES) are useful to identify the levels of incentives that will cover the opportunity costs of farmers supplying ecosystem services. Although auctions are increasingly used for allocation in PES schemes, the factors that lead to their successful implementation and eventual environmental outcomes are poorly understood in developing countries. We investigated the socio-economic and institutional contexts that led to smallholders' auction winning and eventual compliance using linear mixed-effects models, and post-auction and post-contract surveys. We employed a case study of a conservation contract preceded by a sealed-bid, multiple round, uniform price auction for watershed services from coffee farmers in Lampung, Indonesia. The auction participants presented low education levels, low asset endowments and small plot sizes. The study obtained evidence that farmers with larger plot areas were more likely to win the contracts, suggesting economies of scale. Most farmers considered the auction a fair self-selection mechanism to allocate contracts where allocation was not influenced by power or social rank. Non-compliance was associated with labor availability constraints, short duration of land ownership and existence of previous conservation applications, suggesting lax of capability to invest in applying conservation agriculture. Final bids were however not good predictors of compliance, among other factors, calling into question the potential of auctions to elicit the actual incentive from the farmers. Ensuring that farmers understand the purposes of auctions for effective contract allocation beyond a mere game and identifying farmers that might encounter difficulties fulfilling the contract could increase the likelihood that such a PES scheme would be successful.  相似文献   
242.
The main objective of this article is to evaluate determinants of demand for light fuels in Brazil between 2003 and 2013. Through a vector autoregression analysis, an effort was made to identify and quantify the impact of different economic variables and public policy measures adopted during this period on the surprising increase in energy consumption by Brazil’s light-vehicle fleet. The results suggest that demand for energy by the light-vehicle fleet was influenced by an increase in income, by a decrease in fuel prices associated with a policy designed to prevent increases in the price of gasoline from pushing the inflation rate up, by a higher availability of credit for buying vehicles, and by a drop in the real price of those goods, with emphasis on countercyclical measures to waive the tax on industrialized products levied on new vehicles during economic downturns in the automotive industry.  相似文献   
243.
In investigating consumers’ intentions to re-purchase organic personal care products (PCP), this study extends the theory of planned behaviour by including perceived value dimensions as the antecedents of attitude in the model. The findings revealed that most of the hypothesised relationships linking the consumer perceived value constructs (namely, health, safety, hedonic and environmental) with attitude towards the rebuying of organic PCP, were supported. Also, better product knowledge about organic PCP would lead to more positive attitudes towards re-purchasing the product. In contrast, social value was not important in predicting attitude. Similarly, the influence of subjective norm on rebuying intention was not supported. In terms of ranking of importance with regards to prediction of re-purchasing intention, attitude was the most important predictor followed by perceived behavioural control, product knowledge, hedonic value, environmental value and safety value.  相似文献   
244.
论历史逻辑     
历史逻辑是以历史时间的历时性和共时性统一为基础的概念推论,研究关于叙述史中基本概念之间的意义关系和推论规则。过去、现在和未来是历史逻辑的基本范畴,“过去-现在-未来”三段式是历史逻辑的基本公式,它是概念逻辑推论三段式“正题-反题-合题”在历史逻辑中的具体形式。历史逻辑研究的目的,是根据特定历史时段的特殊性,建构以不同时段概念为逻辑变项的历史逻辑,预见未来的发展,规划现在的实践。  相似文献   
245.
在分类应用的过程中,经常会出现新的类别,导致数据分布发生显著变化,使得原分类模型不再适用。如何识别新的类别使分类模型能适应其出现已经成为一个亟需解决的问题。本文提出基于特征增量的SVDD(支持向量数据描述)新类识别方法。该方法在SVDD算法的基础上,通过增加新特征,扩大特征空间维度从而提高模型对于新类的识别能力。在多个数据集上的实验结果表明,该方法能有效识别新类,使更新后的模型具有更高的准确度。  相似文献   
246.
针对多层微波集成电路设计的微带线层间互连问题,介绍了垂直通孔互连、垂直带条互连和层耦合过渡互连三种高性能的互连方法,并且采用三维电磁仿真软件HFSS对这三种互连结构进行了建模和仿真。仿真结果表明,垂直通孔互连和垂直带条互连在0.1~25 GHz的频宽范围内,回波损耗S11<-20 dB,插入损耗S21>-1 dB,互连性能优良,而层耦合过渡互连在20~68 GHz内回波损耗S11 <-20 dB,插入损耗S21>-1 dB,具有在毫米波频段实现互连的潜力。  相似文献   
247.
The objective of this paper is to evaluate the impact of information demand and supply on stock market trading volume. Few studies have demonstrated the role of Google search data in analyzing trading volume activity. In this study, we employ a proxy for information demand which is derived from weekly internet search volume. The latest is from Google Trends database, for 25 of the largest stocks traded on CAC40 index, between April 2007 and March 2014. We use news headlines as a proxy for information supply. We use Garch model to analyze and predict trading volume.The empirical results present new evidences. First, information supply has an impact on trading volume but information demand's impact is much more important. Secondly, by applying MCA to results found, it could be concluded that the impact of public information on transaction volume is conditioned by two elements: the firm and market news disclosure and the second element relates to the characteristics of the market participants, more precisely their news interpretations and their risk aversion. Thirdly, we used Chow structural break test to verify the stability of our model. We found that for securities with structural changes, information demand is the responsible variable of the change in our model. Finally, we found that information variables have a predictive power on transaction volume.This paper contributes to existing literature by incorporating open source internet-based data into the analysis and prediction of transaction volume. Using internet information about the stock market, which has appeared recently as an interesting research for financial empiricists, computer scientists and practitioners, will have a very important utility because quantifying demand and supply of information becomes possible.  相似文献   
248.
The bureaucratic and impersonal nature of public management can fertilize workplace bullying and risks for psychological health and safety. Psychological safety climate (PSC) is an important indicator to reduce psychological hazards. Yet, there have been few studies conducted to examine the existence of PSC in the public sector in non-Western economies. This study examined the implementation of PSC and its effects on 274 employees from six branches of a Vietnamese public sector organization. The results suggest that senior management in organizations should consider positive work conditions and an effective system of policies, procedures, and practices for the prevention of psychosocial hazards.  相似文献   
249.
A small but growing body of literature uses overlapping generations (OLG) models to study environmental policy for long-lived problems such as climate change. An OLG model, unlike the infinitely lived representative agent model, dis- tinguishes between impatience with respect to one's own future utility, and attitudes toward successors' utility. I discuss the problem of time inconsistency, the role of Markov perfection, and show that a class of OLG models can be studied using me- thods developed to analyze models of non-constant discounting. An example illu- strates the techniques and determines the conditions under which, in equilibrium, there is under-investment or over-investment in natural capital.  相似文献   
250.
This article studies a container drayage problem with flexible orders defined by using requiring and releasing attributes as a unified formulation of various order types. A determined-activities-on-vertex (DAOV) graph introduces a temporary vertex set to formulate different truck statuses. The problem is formulated as a mixed-integer nonlinear programming model based on the DAOV graph. Four strategies including a window partition based (WPB) strategy are presented and evaluated extensively to solve the problem. Results indicate that the WPB method could solve the problem effectively and efficiently. Furthermore, this method is robust considering the operating time biases compared to other algorithms.  相似文献   
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