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911.
钢铁行业是河北省的支柱产业,其发展紧密依赖于铁矿资源,保障铁矿资源供给安全,对于河北省钢铁行业乃至国民经济健康发展具有重要的战略意义。改革开放以来,河北钢铁行业的增长速度高于同期GDP增长速度3~5个百分点,未来河北钢铁行业仍将保持较快的增长态势,要实现“十一五”的经济增长目标,河北钢铁行业至少要保持年均15%的增长速度。然而,河北省铁矿资源供给潜伏巨大危机,解决这一问题的出路是增加勘查投入、实施“走出去”的战略、进一步调整钢铁产业结构和加强矿业市场管理。  相似文献   
912.
准确判断广东当前所处经济发展阶段是科学制定广东未来发展战略的前提和基础.从市场经济体系完善程度、工业化进程、经济增长阶段和人均国民收入水平四个维度综合分析,可得出如下结论:广东市场经济体制已基本建立,未来将努力建设现代市场经济体系;广东已处工业化后期最后阶段,将向后工业经济和知识经济过渡;广东已基本完成"起飞"阶段,正进入高额大众消费时代;广东已达中等发达国家水平,将从"发展中经济"向"发达经济"转变.  相似文献   
913.
This paper identifies several positive synergies between social protection programmes and enhanced entitlements to food. One function of social protection is to manage or reduce vulnerability. Several instruments are reviewed – weather-indexed insurance, public works programmes, emergency food aid and buffer stock management – which aim to stabilise income and access to food across good and bad years, or between the harvest and the hungry season. Other social protection instruments aim to raise household income and crop production, for instance agricultural input subsidies or input trade fairs, as well as public works projects that construct or maintain physical infrastructure such as rural feeder roads. This paper also argues that entitlements to food can be strengthened if social justice principles are introduced to the design and delivery of social protection programmes. Examples reviewed include rights-based approaches such as employment guarantee schemes, community-based targeting and demand-driven accountability mechanisms. The paper concludes by arguing for a comprehensive approach to social protection that will achieve sustainable food security, by combining interventions that stabilise income or food production with those that raise income or food production, and are designed and delivered in ways that enhance social justice.  相似文献   
914.
Following the approach of interpolation, this paper proposes the multiple exponential decay model to fit yield curves for both the U.S. TIPS market and the conventional Treasury security market. Several estimation methods, including the unconstrained/constrained nonlinear minimization, quadratic programming, and the iterative linear least squares, are applied to estimate the unknown parameters according to different curve‐fitting purposes. Comparisons between the proposed model and the alternatives show that the multiple exponential decay successfully (1) adapts to a variety of shapes associated with yield curves, (2) (partially) keeps in line with the economic interpretations of Nelson–Siegel summarized by Diebold and Li ( 2006 ), and (3) dominates the competing models in curve‐fitting performance measured by mean fitted‐price errors over the sample period. In addition, the exact specification of a nonparametric interpolation model is pinned down by applying three statistical tools, which enable us to jointly take into account validity, optimality, and parsimoniousness of the proposed model.  相似文献   
915.
This article reviews the past and potential future roles of land tenure reforms and land markets in Sub-Saharan Africa (SSA) as responses to population growth in the process of land use intensification and livelihood transformation. The farm size distribution and the existence of an inverse relationship (IR) between farm size and land productivity in SSA and the implications of this relationship for efficiency and equity are investigated. More secure property rights and removal of restrictions on land markets have the potential to create both efficiency and equity benefits, but there are high risks of elite capture of large land areas with inefficient and inequitable outcomes. This situation is the case not only in land-abundant areas but also in urban and peri-urban areas where increasingly larger proportions of people will make their living. Increasing population pressure in densely populated rural areas contributes to more rapid rural–urban migration, and creating alternative livelihood opportunities for the migrating youth population is essential to achieving economic development with social stability.  相似文献   
916.
917.
Bangladesh has made considerable progress against human development indicators in recent years, but malnutrition resulting from poor dietary diversity and low micronutrient intakes remains entrenched. Fish is central to the Bangladeshi diet and small fish species are an important micronutrient source. Although fish consumption per capita has increased in recent years as a result of rapid expansion of aquaculture, it is likely that consumption of fish from capture fisheries (including small indigenous species particularly rich in micronutrients), has declined. This paper evaluates data on fish consumption collected in Bangladesh by the International Food Policy Research Institute in 1996/7 and 2006/7 to assess changing patterns of fish consumption and their implications for food and nutrition security. This analysis indicates that growth of aquaculture has been positive, mitigating a sharp reduction in the quantity of fish consumed from capture fisheries and smoothing out seasonal variability in consumption. However, increased availability of fish from aquaculture may not have fully compensated for the loss of fish from capture fisheries in terms of dietary diversity, micronutrient intakes and food and nutrition security, particularly for the poorest consumers. A range of approaches are recommended to sustain and enhance the contributions capture fisheries and aquaculture make to food and nutrition security in Bangladesh  相似文献   
918.
运用沉积学、岩石学等,结合钻孔资料对平庄盆地含煤岩系沉积相及聚煤规律进行了分析。根据含煤岩系各种成因标志的分析研究,识别出的沉积相类型有冲积扇相、扇三角洲相、河流相、三角洲相及湖泊相。论述了各煤系沉积相类型的空间配置及不同环境的聚煤规律。  相似文献   
919.
Maize is the most important food staple in Eastern and Southern Africa, with a highly seasonal production but relatively constant consumption over the year. Farmers have to store maize to bridge seasons, for food security and to protect against price fluctuations. However, the traditional storage methods do not protect grain well, resulting in large postharvest losses. Hermetically sealed metal silos kill storage pests by oxygen deprivation without pesticides. Popular in Central America, they are now being promoted in Africa, but their impact here has not yet been studied. This study used propensity score matching to evaluate the impact of metal silos on duration of maize storage, loss abatement, cost of storage, and household food security. Metal silo adopters (N = 116) were matched with non-adopting farmers from a representative sample of 1340 households covering the major maize-growing zones in Kenya. The major effect of the metal silos was an almost complete elimination of losses due to insect pests, saving farmers an average of 150–200 kg of grain, worth KSh9750 (US$130). Metal silo adopters also spent about KSh340 less on storage insecticides. Adopters were able to store their maize for 1.8–2.4 months longer, and to sell their surplus after five months at good prices, instead of having to sell right after the harvest. The period of inadequate food provision among adopters was reduced by more than one month. We conclude that metal silos are effective in reducing grain losses due to maize-storage insects, and that they have a large impact on the welfare and food security of farm households. The initial cost of metal silos is high (KSh20,000/1.8 ton) and therefore policies to increase access to credit, to reduce the cost of sheet metal, and to promote collective action can improve their uptake by smallholder farmers.  相似文献   
920.
Within a context of delivering food security into the future, dietary guidelines are being reframed, corporations are replacing unsustainable products, and consumers are being encouraged to become ecological citizens. While there is a growing literature on the food practices of ‘alternative’ consumers, ‘mainstream’ consumers are less well understood. This paper describes qualitative research undertaken in a socio-economically disadvantaged area of Sydney, Australia, which aimed to uncover consumer views towards sustainable and healthy diets. Most participants indicated a discrepancy between their desired and actual behaviours: while they want to support Australian, or local, food producers they gravitate towards cheap and tasty food from ‘anywhere’; and while they associate nutritious food with fresh food, they will buy processed foods which can be less expensive, appeal to children and are prone to less waste. Reflecting mainstream Australian political culture, participants were compromising household food budgets in order to pursue a socially acceptable standard of living (including decent housing, car-reliance). They were also incorporating the pleasure and desires of family members as part of ‘the moral arts of everyday life’. Using social theories of consumption and practice sociology we argue that food choices and practices – easy or not – need to be interpreted as part of the role that consumption plays in political citizenship and moral subjectivity. In the Western Sydney context, food practices are essentially household budget and family nourishment practices rather than nutrition and sustainability practices; a position which is not addressed in the government’s new food policies or wage determination processes.  相似文献   
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