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51.
This article examines the role of small- and medium-sized multinational enterprises (MNEs) in the dynamic development of global production networks (GPNs) in the maritime industry. It studies the dynamism between subsidiaries of Norwegian maritime firms and regional actors and institutions in the Greater Shanghai Region of China from the perspectives of the subsidiaries. It argues that strategic coupling, recoupling and decoupling are partly the results of regional selection mechanisms. However, in the cases where the subsidiaries are embedded within the host region, the strategies and behaviour of MNEs are of decisive importance for the dynamic development of GPNs. 相似文献
52.
[目的]开展农业干旱危险性评价与区划研究,为辽宁省西北地区农业防旱抗灾工作提供科学依据。[方法]文章根据联合国国际减灾战略署(ISDR)对农业干旱危险性的定义,分析了构成研究区作物干旱危险性的致灾因子和孕灾环境因子,采用层次分析法确定了各因子的权重,构建了研究区农业干旱危险性评价指标和模型。以2009年为例,通过利用降雨、土壤、农业生产类型及地形等数据计算了辽西北地区农业干旱危险性评价指数,利用自然间断点法分级干旱危险性评价指数,并借助GIS技术,绘制研究区农业干旱危险性等级区划图。[结果] 2009年作物生长期间研究区农业干旱危险性由高到低排列为:朝阳市葫芦岛市锦州市阜新市铁岭市沈阳市。[结论]辽西北地区农业干旱危险性等级区的划分,能够帮助政府管理部门为面临干旱威胁不同的区域建立适当的防灾方法和有效的应急预案。 相似文献
53.
《Food Policy》2019
This article tests the hypotheses of convergence to a single level of total factor productivity (TFP), and a steady state of TFP growth rate in China’s agricultural sector. Based on multilateral TFP estimates we found that China’s agricultural sector has rebounded in recent years from a slower TFP growth in the 2005–2007 period. While convergence test results confirm a “catch-up” effect that provinces with lower TFP levels tend to grow faster than others, estimated rates of β convergence are conditional on how we capture the heterogeneity effect across regions. The rates of β convergence range from 0.016 to 0.039 under different model specifications. Estimates show that higher growth rates of educational attainment, R&D, and intermediate goods density (per unit of labor) can enhance TFP growth. Unfortunately, there is no evidence of an overall σ convergence, indicating that TFP levels are not converging except in the South region. It implies that to catch up with leading provinces, it would require extra efforts for those lagging behind by increasing their region-specific research investment, promoting rural educational attainment, and enhancing embodied technical change. 相似文献
54.
耕地流转与规模经营改善了农业环境吗? ——基于耕地利用行为对农业环境效率的影响检验 总被引:1,自引:0,他引:1
研究目的:基于2007—2016年26省农业生产数据,测算"面源污染"和"碳排放"两类非期望产出下的农业环境效率,构建"耕地流转—利用规模—利用方式与利用强度—农业环境效率"的传导路径并进行计量检验。研究方法:超效率SBM模型,中介效应模型。研究结果:(1)耕地流转并未显著提高农业环境效率,但耕地利用规模对农业环境效率的影响呈倒U型;(2)耕地流转有助于扩大耕地利用规模,进而在样本中对农业环境效率呈现负向影响。与此同时,耕地流转对农业环境效率也存在正向的直接效应,正负效应基本抵消;(3)耕地利用规模主要通过改变化肥和机械投入强度进而负向影响农业环境效率。研究结论:农业环境效率受耕地流转、利用规模、利用方式和强度等多重因素影响,呈现明显的传导路径,因此,为了提高农业环境效率,在积极推行土地流转和规模化经营政策时,要注意结合地区农业生产力和地理环境,避免盲目扩大经营规模,同时鼓励规模经营主体引进农业绿色环保技术,注重农业生产资料的合理利用。 相似文献
55.
Gerardo Angeles-Castro Laura Josselin Arriola-Barcenas Carlos Bonifacio Baeza-Almaraz 《Applied economics letters》2018,25(21):1531-1534
By using panel data analysis across 368 water utilities in Mexico over the period 2010–2014, we find that small firms are more efficient than medium and large providers and that increasing production is associated with less efficiency. Billing, income collection and profitability are relevant factors to improve efficiency. Medium and large firms require to measure consumption by service with meters in order to increase efficiency, while small firms do not require it. 相似文献
56.
农业科技园区专项项目是围绕影响农业产业化关键技术开展研究攻关,把具有市场开发前景的先进适用技术应用于产业化经营上而设立的科技研发项目。研究选取了2014-2016年列入宁夏自治区重点研发计划农业科技园区专项的69 个项目,从项目的执行情况、完成效果、组织管理以及经济和社会效益等方面进行绩效评价,并提出了存在的问题和建议。 相似文献
57.
中国农药施用与农业经济增长脱钩状态:时空特征与影响因素 总被引:1,自引:0,他引:1
[目的]明确农药施用与农业经济增长关联状态及其影响因素,为实现"控药减害增收"的目标提供借鉴。[方法]基于2005—2015年数据利用脱钩理论和对数平均分解指数法分解进行分析。[结果]中国农业经济增长伴生大量农药施用,仅少数省域表现出农药施用和农业经济增长扩张绝对脱钩的理想状态,东北西北部分省域农业经济增长则以更大幅度的农药投入增长为代价。中西部地区劳动力规模和技术进步效应是推动农药施用与农业经济增长脱钩的因素;东部地区种植规模变化、劳动力规模和技术进步因素均是推动农药施用和农业经济增长脱钩的因素;东北地区仅劳动力规模效应成为推动脱钩的力量。[结论]推动农药施用与农业经济增长脱钩需要强化农业科技的创新与普及,完善农业生产过程中的技术支撑,推动农业病虫害监测预警,加大对环境友好型低污染农药和肥料的推广度;构建农户施药的多重约束机制,完善农业病虫灾害保险减少农户对生产过程的风险感知,发挥农业合作社对农户施药行为的规制作用,完善产品分级认证和安全准入制度;通过农地合理流转和农业机械化等方式集约利用农业生产资源;因地制宜推动农药施用与农业经济增长脱钩,结合区域资源优势和农业发展阶段有针对性地设计对策措施。 相似文献
58.
《Food Policy》2019
This research studies the determinants of pig farmers’ participation in farmers’ cooperatives and the effects of farmers’ cooperatives on pig farmers’ behaviors in adopting safe production practices using data from a household survey of 540 cooperative farmers and 270 non-cooperative farmers from four main pig production provinces in China. The propensity score matching (PSM) method was adopted to deal with possible self-selection bias associated with farmers’ participation in farmers’ cooperatives due to observables, which is further supplemented by a sensitivity analysis to assess the degree to which the PSM results are robust to the presence of unobservables. The PSM results show that the cooperative membership has significant and positive influence on farmers’ propensity to adopt safe production practices and the effects are heterogeneous across a number of key cooperative, farm and household attributes. Specifically, the membership effects tend to be bigger for cooperatives led by Investor-owned firms (IOFs) and farms of small production scale. And the effects tend to be greater for households (1) of medium and high level of education, (2) of less than 10 years of pig production experience, (3) of no off-farm job experience, and (4) that are specialized in pig production. The sensitivity analysis further increases our confidence in the results for the feed use and the breed use, however, the results for vaccination, drug use and waste disposable are more sensitive to the influence of unobservables, therefore should be interpreted with caution. 相似文献
59.
60.
《Socio》2018
The aim of the paper is to identify which among the aspects that relate to the composition of the student body, school (district) size, management practices and the school principals' own characteristics are associated with the performance of Italian students at grade 8, measured through standardised test scores in reading and mathematics. The analysis makes use of a student-level efficiency model, and several school level variables are included as explanators for efficiency scores. The results show that, especially for reading, the most influential variables relate to the composition of the student body, while the students' performance in mathematics is partly correlated with the management practices adopted by the school principal/head teacher. Schools and schooling can only explain a minor part of the variance in achievement scores, however, and the characteristics of the students themselves play the most significant role. 相似文献