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1.
Farmers in the Vietnamese Mekong Delta face a wide range of climate-related and hydrological factors which threaten rice production. Smallholder farmers must adapt to climate change to sustain rice production as their central and most important livelihood activity. A sample was stratified across agro-ecological areas in the Delta affected by flooding, alluvial soils, acid sulphate soils, and saline water intrusion and by derived farmer typologies. A rural livelihoods approach was used in focus group discussions and in-depth interviews to identify and enumerate enabling and constraining adaptation factors. Smallholders experienced diverse natural hazards such as floods, abnormal rains, high temperatures, water scarcity, and salinity intrusion specific to the agro-ecological areas. Adaptation was constrained by labour shortages, water quality, topography, access to combine harvesters, transportation infrastructure, dryers and household savings. Adaptation was enabled by farming techniques and experience, cooperative groups, water quantity, access to information, and ability to purchase agro-chemicals through credit. Small farmers (< 1?ha) were more constrained than large farmers (> 1?ha) who had an expanded livelihood asset base. A range of policy implications are discussed, but adaptation is not just about technological fixes but requires overall improvements in a range of human, social and financial components.  相似文献   
2.
基于汇率传递的风险溢价渠道,本文将我国利率调控通胀、外汇储备对冲干预汇率纳入新凯恩斯政策模型,构建双目标双工具政策分析框架,比较泰勒规则与双目标双工具规则下通胀目标与汇率目标共存的经济机制与效应。本文模拟显示:(1)双目标双工具政策框架下通胀目标与汇率目标能够共存,此时通过影响汇率风险溢价来盯住汇率不影响通胀;而单工具政策下两目标无法共存,此时降低国内资产的收益率盯住汇率会刺激居民的消费行为引起通胀。(2)国际资本冲击下,双目标双工具政策在固定汇率的同时能保证经济稳定;而当贸易条件恶化时,选择完全浮动汇率制度最优。央行政策损失分析进一步验证了以上结论。(3)随着金融市场化改革深入,外汇储备稳定汇率的有效性将下降,冲销成本会大幅提升。资本账户开放下,双目标双工具政策仍是央行抵御外部资本冲击的首选政策;但是汇率市场化后,通胀目标制与双目标双工具政策效果基本无差异。本文结论的启示是:面对国际资本,需必要的汇率管制;但是面对贸易冲击,可适度提升汇率弹性来减少冲击对产出和通胀的影响。  相似文献   
3.
陆倩  何建佳 《科技和产业》2021,21(11):58-62
以一条由制造商和零售商组成的二级供应链为研究对象,通过测算产业互联度与双循环程度,研究对供应链合作稳定性的影响.研究发现:在国内环境中,产业互联度与内循环程度呈正比关系,产业互联度越高,内循环程度越高;内循环度程度提高,内需扩大,供应链上的企业选择合作时的整体收益要大于不合作时的收益,因此达到供应链长期稳定合作.通过从国内角度寻找出的规律应用于国际供应链中,为企业参与全球经济提供启示.  相似文献   
4.
Banking groups exploit double leverage when ‘debt is issued by the parent company and the proceeds are invested in subsidiaries as equity’. Financial authorities have frequently raised concerns about the issue of double leverage because this type of intra‐firm financing appears to allow for both the arbitrage of capital and the assumption of risk. This article focuses on the relationship between double leverage and risk‐taking within banking groups. First, we discuss this relationship based on an examination of balance sheet figures. Second, we analyze a large sample of United States Bank Holding Companies (BHCs) from 1990–2014. The results show that BHCs are more prone to risk when they increase their double leverage, namely, when the stake of the parent within subsidiaries is larger than the stand‐alone capital of the parent. This paper's primary implication for policymakers is that the regulators of complex financial entities should more efficiently address the issue of double leverage, thereby limiting the potential negative consequences that arise from corporate instability.  相似文献   
5.
基于冠层光谱和BP神经网络的水稻叶片氮素浓度估算模型   总被引:4,自引:0,他引:4  
[目的]快速、准确地诊断水稻叶片氮素营养状况,为水稻氮肥精准管理提供依据。[方法]以江西省农科院8种不同施肥处理的晚稻为研究对象,于主要生育期同步测定了水稻冠层光谱反射率及叶片全氮浓度(Leaf Nitrogen Concentration,LNC),系统分析了原始光谱反射率、一阶微分光谱、"三边"参数以及由350~1 350nm两两波段组合的差值(SD (Rλ1,Rλ2))、比值(SR (Rλ1,Rλ2))及归一化(ND(Rλ1,Rλ2))光谱指数与水稻LNC的相关关系,筛选出敏感参数,并以之为自变量构建了水稻LNC的传统预测模型,另外构建不同指标个数的多元线性与BP神经网络模型,并对模型进行验证。[结果](1)水稻LNC与一阶微分光谱在751nm处的相关性最高(r=0. 822);(2)"三边"参数中的红边面积SDr与LNC的相关性较高(r=0. 687);(3) 750nm附近的红边波段与近红外波段差值组合、550nm附近的绿光波段与近红外波段的比值及归一化差值组合与水稻LNC的相关性较高,以SD (R752,R751)、SR (R534,R1 350)和ND (R534,R1 349)表现最好,相关系数分别为0. 827、-0. 790和0. 788;(4)传统回归模型中以SD(R752,R751)构建的一元线性模型最佳(RC2=0. 665、RV2=0. 750、RMSEV=0. 4%、RPD=2. 034);(5)利用5个指标((R'751、SDr、SD (R752,R751)、SR (R534,R1 350)、ND (R534,R1 349))经逐步回归筛选出的2个指标SD ((R752,R751)和SR (R534,R1 350))构建预测水稻氮素的BP神经网络模型,预测效果最佳,其验证参数值分别为R2=0. 859、RMSEV=0. 302%和RPD=2. 669。[结论]基于单指标构建的传统线性模型计算过程简单但精度略低,而基于2个指标(SD (R752,R751)、SR (R534,R1 350))构建的BP神经网络模型预测精度高于该2指标构建的多元线性模型,表明在指标适合的情况下,BP神经网络对氮素具有较好的预测能力,是一种快速准确估算水稻叶片全氮浓度的方法。  相似文献   
6.
A carbon tax is potentially a policy that can reduce CO2 emissions and mitigate climate risks, at lowest economy-wide costs. We develop a dynamic CGE model for Spain to assess the economic and environmental effects of a carbon tax, and test the double dividend (DD) hypothesis. We simulate the impact of three carbon taxes: €10, €20 and €30 per ton of CO2. For each tax, four ‘revenue recycling’ scenarios are examined: a reduction of taxes on capital, on labor, on value-added tax, and a scenario in which revenues are not recycled. We find a DD for taxes of €10/ton and lower, within five to seven years of implementation. We estimate an annual CO2 emissions reduction of around 10% with this tax. Under some circumstances, the DD can be achieved for a tax of €20/ton. In any case, recycling revenues to cut pre-existing taxes reduces costs of imposing carbon taxes.  相似文献   
7.
Even when the neoliberal ideology of the free market was more dominant than it now is, the state was involved in economic activities that could be undertaken by private firms. State capitalism takes increasingly diverse forms, including beyond direct, partial or even indirect ownership. This paper briefly reviews some of these forms without claiming to be exhaustive as the shape state capitalism takes differs widely across the institutionalized contexts of countries. We assess state capitalism using Polanyi’s double movement framework and argue that this framework needs adaptation to novel forms of state capitalism that include, e.g., state-owned multinationals and sovereign wealth funds.  相似文献   
8.
Narrowing the gender technology gap in agricultural production has become a critical policy issue in sub‐Saharan Africa. A better understanding of the gender technology gap is essential for policy formulation and programme planning to ensure equity in resource allocation, and household‐level food security in low and middle income countries, such as Ghana. We employ a metafrontier approach to analyse the differences in the efficiency of male and female farmers, recognising the endogeneity of some of the variables in the inefficiency effects model, in particular the credit constraints of the rice farmers under study. Our findings show that while the rice farms themselves are very similar, average yields for male managed farms tend to be significantly higher than female managed farms reflecting higher seeding and fertiliser application rates on male managed farms. However, there is no significant difference between the genders in either land used for rice or total output per farm household. We find some evidence that relative to the metafrontier, male managed farms are less efficient than female managed farms. The results further show gender technology gap amongst the smallholder rice farmers with females’ technology gap ratio being significantly greater than that of males, with females operating on a production frontier closer to the metafrontier. Policies that provide females more access to productive resources and other agricultural services could assist in the generation of relatively higher output.  相似文献   
9.
[目的]我国粳稻产量现阶段呈连续增长的态势,然而粳稻生产效率却存在无效率或波动剧烈的现象,研究我国的粳稻生产效率,有助于提升和稳定中国粳稻区域生产效率和水平从而间接保障我国粮食安全。[方法]使用超效率DEA方法测算中国13个粳稻生产省份的生产效率,分别从时间和区域上的差异进行分析。[结果]中国粳稻生产技术效率在时间趋势上逐渐趋于平稳,但是在2004—2007年间存在短暂的波动;在区域上主要是西南和东北粳稻生产区的技术效率水平较高,西北区在技术效率、纯技术效率与规模效率上都处于较低的水平;虽然河南、湖北、宁夏3个省份出现技术无效率,但规模报酬都处于递增的状态,仍有提升生产效率的潜力,应通过减少要素投入冗余来改变其无效率状态。[结论]粳稻生产技术无效率主要是由于种子费用、农药费用等生产要素的投入冗余造成的;若将来在保持纯技术效率和其他条件不变的情况下,通过提升规模效率水平会进一步提升我国粳稻的整体技术效率水平。基于上述分析有针对性地提出制定粳稻生产区域规划、发展适度规模经营、改善生产要素使用效率3方面的政策建议。  相似文献   
10.
ABSTRACT

This article aims to overcome an impasse in current Polanyian scholarship by suggesting a new vocabulary to explain Polanyi’s ‘double movement’ and ‘countermovement’ concepts – the unconscious countermovement and the conscious Polanyian movement. It argues current literature often misinterprets these core concepts, which can lead to a misunderstanding of Polanyi’s general thesis. This paper uses the Carton (2018. On the Nature of the Countermovement: A Response to Stuart et al.’s ‘Climate Change and the Polanyian Countermovement: Carbon Markets or Degrowth?’. New Political Economy)-Stuart et al. (2019. Climate Change and the Polanyian Counter-movement: Carbon Markets or Degrowth? New Political Economy, 24 (1), 89–102) debate on the countermovement to exemplify some of the current misapplications of the countermovement as explicitly ‘anti-capitalist’ (Stuart et al. 2019. Climate Change and the Polanyian Counter-movement: Carbon Markets or Degrowth? New Political Economy, 24 (1), 89–102) movements. This paper argues that in fact all countermovements, as described in The Great Transformation, are necessarily non-ideological. I argue that dialectics and consciousness are fundamental to understanding the double movement and countermovement concepts and that highlighting the conscious/unconscious dynamic within Polanyi’s work helps avoid misreadings of key concepts and provides a clearer and more comprehensive understanding of Polanyi’s general theory.  相似文献   
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