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41.
The paper outlines EU policy on bioenergy, including biofuels, in the context of its policy initiatives to promote renewable energy to combat greenhouse gas emissions and climate change. The EU’s Member States are responsible for implementing EU policy: thus, the UK’s Renewables Obligation on electricity suppliers and its Renewable Transport Fuel Obligation and road‐fuel tax rebates are examined. It is unlikely that EU policy is in conflict with the WTO Agreement on Agriculture or that on Subsidies and Countervailing Measures, but its provisions on environmental sustainability criteria could be problematic.  相似文献   
42.
采用我国30省(市、区)2003—2012年面板数据,分析环境规制强度、能源消费结构与雾霾之间的关系。首先,以PM10浓度指标进行聚类,把30省(市、区)划分为高、中、轻三大污染地区。其次,面板单位根检验结果显示各变量是一阶单整I(1);Pedroni和Kao协整检验表明变量之间存在协整关系;FMOLS回归发现,全国总体环境规制强度与PM10浓度呈反方向变动,能源消费结构与PM10浓度呈同方向变动;高污染地区能源消费结构对PM10浓度产生正的影响,中、轻污染地区环境规制强度对PM10浓度产生负的影响。最后,提出了使用法律、经济手段加强环境规制,降低煤炭消耗比例、发展清洁能源等建议。  相似文献   
43.
Recent increases in food and other commodity prices have highlighted concerns that many poor countries are net food importers and higher food prices would worsen their trade balances. In this article, we analyze the changes in food trade balances associated with the 32% increase in food prices from 2000/2001 to 2004/2005. We find a small deterioration in food trade balances of low‐income countries and an improvement in middle‐income countries. The deterioration is most severe for countries in conflict and small island states, so attention should be placed first on these countries and on a few very‐low‐income countries that are also vulnerable. Because low‐income countries as a group had much lower agricultural GDP growth rates than middle‐income countries, the answers to food vulnerability in low‐income countries should probably be addressed within the context of incentives for agricultural production.  相似文献   
44.
Dutch glasshouse firms are facing the introduction of a system of tradable CO2 emission quotas. This paper employs a non‐parametric method for modelling tradable CO2 emissions of Dutch glasshouse firms. The method is capable of generating shifts in CO2 emissions across the sample of firms. Moreover, changes in volumes of outputs produced and inputs used are computed. Results show that firms using a conventional heating technology will be net purchasers of CO2 emissions, whereas firms using more advanced heating technologies will sell part of their emission quota.  相似文献   
45.
In this article, we reassess the role of marketing boards and similar arrangements that have played an important role in numerous agro‐food sectors of developed countries over almost a century. Referring to transaction cost economics and to more recent contributions on the allocation of decision and property rights, we interpret these arrangements as hybrid modes of governance. We hypothesize that uncertainty is the leading force pushing toward these organizational solutions and we explore forms of uncertainty at stake and their impact in shaping various types of hybrids. We also explore the role of institutional embeddedness in providing marketing boards and the like their legitimacy. Using numerous examples from Canadian marketing boards, we discuss the benefits and point out flaws of these arrangements. We conclude on the need to assess comparatively the role of these solutions with respect to, for example, a system of bilateral contracts.  相似文献   
46.
In this work we estimate human capital returns in the Spanish hospitality sector using an expanded version of the Mincer wage equation (1974). In addition, wage differences in the main tourist regions are quantified using the wage decomposition of Oaxaca (1973) and Blinder (1973) from a gender perspective. Using data from the 2006 Spanish Wage Structure Survey (Encuesta de Estructura Salarial), all the regions under analysis show lower education returns in the hospitality sector when compared to other private services. The same results are found for the other human capital variables used. There are significant differences in education returns between regions, especially in Catalonia and the Canary Islands. The main wage gap in the Canary Islands and the Madrid region is due to differences in returns in the observed variables, whereas in other regions most of the differences are due to the resources allocated. Furthermore, gender wage differences are found in all the regions. The largest estimated wage gap between men and women occurs in the Balearic Islands followed by Catalonia and the Community of Valencia. In contrast, equality between genders is greater in the Community of Madrid.  相似文献   
47.
利用辐射源目标的频移动态特征进行盲分选时,针对已有的分选方法不能很好解决非合作接收数据非周期、间断、交叠的问题,提出了一种改进的逻辑回归分选算法,将信号分选转化为轨迹分类的问题来处理。首先,借鉴多目标航迹起始模型中的M/N逻辑法的框架,设计新的数据关联门限,以建立目标起始曲线;其次,采用最小二乘拟合方法替代卡尔曼滤波,设计新的外推规则,建立载频变化预测曲线;分析新的接收数据与预测曲线的关联性,不断迭代回归或形成新的分支,最后获得目标分选结果。仿真与实测试验表明,利用逻辑回归分选算法,对不同运动目标搭载的同频辐射源可进行自动分选,4个仿真目标与2个真实目标的分选正确率达到100%。同时,该方法拓展了辐射源目标盲分选中的动态频移特征应用,为辐射源个体识别提供了新的支持。  相似文献   
48.
In this article, I draw lessons from two quasi‐natural experiments (the transition process in former Communist countries and the rapid globalization of food chains) on the optimality of farms and agricultural structures more generally. I argue that (a) the farm structures that have emerged from the transition process are much more diverse than expected ex ante; (b) this diversity is to an important extent determined by economic mechanisms which are influenced by initial conditions and reform policies; (c) non‐traditional farm structures have played an important role during transition because they were optimal to address the specific institutional and structural constraints imposed by the transition process; (d) there is more diversity than often argued in the farms that are integrated in global food chains; (e) endogenous institutional (contracting) innovations in food chains may lock existing farm structures in a long‐run institutional framework; and (f) indicators based on farm structures are not a good measure of welfare effects of the globalization of food chains.  相似文献   
49.
If future demand for maize in Latin America and the Caribbean region (LAC) is to be met from local sources, domestic production must continue to increase. Because further expansion in the area planted to maize is precluded by the limited availability of arable land, future increases in production will have to rely heavily on the spread of productivity‐enhancing hybrid technology. Until now, the diffusion of hybrid maize in LAC has been quite variable. Using data from 18 countries, we investigate factors affecting the hybrid maize diffusion rate. Our findings validate conventional profitability‐based explanations of producer adoption behavior, but they also confirm the importance of supply‐side factors, thereby providing empirical support for the life cycle theory of seed industry development. We conclude that if policy makers in LAC are to accelerate the diffusion of hybrid maize, they will have to ensure an environment in which it is not only profitable for producers to adopt improved germplasm, but also profitable for the seed industry to produce and sell high‐quality seed.  相似文献   
50.
This study examines the nature of the relationship between formal agricultural credit and agricultural Gross Domestic Product (GDP) in India, specifically the role of the former in supporting agricultural growth, using state level panel data covering the period 1995–1996 to 2011–2012. The study uses a mediation analysis framework to map the pathways through which institutional credit relates to agricultural GDP relying on a control function approach to tackle the problem of endogeneity. The findings from the analysis suggest that over this period, all the inputs are highly responsive to an increase in institutional credit to agriculture. A 10% increase in credit flow in nominal terms leads to an increase by 1.7% in fertilizers (N, P, K) consumption in physical quantities, 5.1% increase in the tonnes of pesticides, 10.8% increase in tractor purchases. Overall, it seems quite clear that input use is sensitive to credit flow, whereas GDP of agriculture is not. Credit seems therefore to be an enabling input, but one whose effectiveness is undermined by low technical efficiency and productivity.  相似文献   
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