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101.
It is generally believed that tenure security has improved due to the programme of land certification. In this paper I argue the opposite. Tenure security concerns three different rights: possession, renting and latent rights. Rights of possession are believed to have improved, but the evidence is weak and conflicting. Land rentals are expanding and farmers face high tenure insecurity. The main problem, though, is latent rights, with great insecurity and increased conflict levels. Despite rapid economic development there is considerable social malaise, an unfortunate agricultural structure, and considerable pressure for land redistribution due to unresolved land tenure issues. The paper is based on the certification literature and primary material from North Shäwa. 相似文献
102.
建筑工程施工的组织设计是建筑工程的必要保障。近些年以来,随着我国经济的迅速发展,原有的建筑工程施工组织计划已经完全不能适应目前的施工建设了,根据建筑工程组织设计所存在的这些问题及改进措施提出改进措施,使建筑工程组织设计发挥出真正的重要作用,以达到经济效益与社会效益双丰收的目的。 相似文献
103.
Faaiqa Hartley Dirk van Seventer Paul Chimuka Samboko Channing Arndt 《Development Southern Africa》2019,36(2):213-232
ABSTRACTPotential biofuel demand in South Africa is estimated to increase to 1550 million litres by 2025 due to mandatory blending rates. Land and water constraints, however, limit the ability for domestic production. Zambia, due to its abundance in land, suitable climate, supportive set of bioenergy incentives and close geographical location to South Africa, has the potential to meet this increase in demand. Using a dynamic recursive computable general equilibrium model, we estimate the macro- and socio-economic impacts of bioethanol production in Zambia from three potential crops: sugarcane, cassava and sweet sorghum. The results show that the development of a single product bioethanol industry has the potential to increase economic growth without negatively affecting overall food security. Further expansion of the industry to multiple products results in larger gains to growth and welfare. 相似文献
104.
P. Li Donni 《Applied economics letters》2018,25(11):791-795
This article studies poverty persistence and the role of social security programmes on poverty among elderly in the US. We use a Latent Markov model to disentangle unobserved heterogeneity and state dependence. Because of its dynamic nature, unobserved heterogeneity is modelled to vary over time. This allows to capture different latent states of poverty that change over time. Result indicates the existence of three unobserved types evolving over time according to their propensity to be poor. Moreover, a strong persistence in poverty especially for women, individuals living alone and ethnic minorities is found. Finally, the estimates indicate that giving social assistance tends to reduce poverty. 相似文献
105.
基于免疫机理的黑龙江省耕地系统安全预警研究 总被引:3,自引:0,他引:3
研究目的:科学识别黑龙江省耕地系统安全警情现状及其未来发展趋势。研究方法:改进突变级数模型和Elman神经网络模型。研究结果:(1)构建基于生物免疫机理的耕地系统安全警情评定指标体系,得出黑龙江省警情1995—2014年整体呈波动上升趋势,警度从"无警"上升至"轻警",再至"中警",说明基于改进突变级数模型的评价结果可凸显评价对象之"优、劣"特征;(2)引入Elman神经网络构建耕地系统安全警情预测模型,测试拟合精度在0.97以上,预测结果可靠,表明未来20年黑龙江省警情将整体呈先升高、后降低趋势,警度在"轻警"与"中警"之间。研究结论:基于生物免疫机理的黑龙江省耕地系统安全预警研究,可为省域尺度下耕地系统安全预警提供一种新的思路。 相似文献
106.
With international food price shocks in 2008 and 2011, food security became a political priority in many countries. In addition, some politicians have recently adopted a more nationalistic stance. Against that background, this paper critically investigates the prospects of increased food production within a national context. We use a small, high-income country, Norway, as an empirical case. In 2012, the government set a goal of increasing agricultural food production by 20% by 2030. We ask: 1) How has food production in Norway developed before and after the goal was set? 2) What plans do farmers have, and what do they regard as the main obstacles to increased production? We apply a mixed method combining public statistics, a survey, and interviews. We analyze four production systems: a) milk; b) grass-based meat; c) combined pig and grain; and d) grain. These systems represent around 80% of the domestically consumed food produced on farms in Norway. Since 2000, aggregate food production has had a slight downward trend with periodic fluctuations. Based on a political economy approach, we identify land and labor as the most limiting factors. Capital is less of a hindrance and offers a potential for increased production. Farmers have modest expectations of increased production, though. This outlook resonates with the strong integration of agriculture into the wider economy, at both micro and macro levels, making it challenging to implement new policies and change farm practices on a broad basis. Increases in some specific products, however, are realistic. 相似文献
107.
108.
This study aims to know what are the factors determining the adoption of M-Banking app among customers in Cameroon. In other words, what are the factors that influence users in their decisions to adopt and use a system or technology such as the MBanking app, and indirectly, what is the impact of this use on both the customers and financial inclusion? The research model developed relying on a combination of Technology Acceptance Model (TAM ), Unified Theory of Acceptance and Use of Technology ( UTAUT2 ), Information System Success Model ( ISSM ), and Protection Motivation Theory ( PMT ) and other constructs; it was then tested with a sample of 223 users of the “ SARA” M-Banking app of the financial institution called “ Afriland First Bank” . Findings revealed that: (1) utilitarian expectation, hedonic motivation, and status gain, habit, and perceived privacy concern have a significant influence on the intention to adopt M-Banking apps; and (2) the exploitative/explorative use of this technology has an impact on user’s loyalty and satisfaction but also contributes strongly to fostering financial inclusion in Cameroon. Also, the Multi-group analysis was performed on the sample using 2 gender-based groups (males, n=121; females, n=102). 相似文献
109.
[目的]探索叶尔羌河平原绿洲土地生态安全预警问题及其时空格局变化,旨在为叶尔羌河平原绿洲土地生态安全及可持续利用提供科学的参考依据。[方法]文章运用PSR模型构建预警指标体系,采用熵值法测算各指标权重,对2000—2016年叶尔羌河平原绿洲土地生态安全警情格局进行综合分析,并利用GIS技术分析其2000年、2005年、2010年和2016年土地生态安全空间格局变化,最后运用障碍度模型探索其障碍因子。[结果](1)2000—2016年叶尔羌河平原绿洲土地生态安全综合预警指数总体呈上升态势,生态预警状态由"较不安全"转为"临界安全",警度亦由"重警"变为"中警"。(2)从空间格局来看,空间上各县域土地生态安全水平差异明显,研究初期西部地区土地生态安全状态优于东部地区, 2016年呈现出中部高、东北—西南部低的态势。(3)近17年叶尔羌河平原绿洲各县域土地生态环境状况有所改善,安全状态经历了"极不安全—临界安全—较安全"的发展历程。(4)影响土地生态安全的主要障碍因子包括单位面积耕地农药负荷、人口密度、单位面积耕地化肥负荷、土地垦殖率、人口自然增长率和单位面积耕地地膜负荷等。[结论]研究期间叶尔羌河平原绿洲土地生态安全得到明显的提升与改善,并在良好的方向发展。 相似文献
110.
Myopic agents lack the foresight to save for their own old age. It is generally believed that correcting myopia is a rationale for a pay-as-you-go (PAYG) pension system. This view has been supported by existing literature showing that the optimal PAYG social security tax should increase when people are more myopic. In this paper we obtain new results opposed to the traditional view. By establishing a very standard general equilibrium OLG model with myopic agents and endogenized marginal product of capital, we show that the optimal social security tax should be lower when people are more myopic. Our numerical analysis also shows that the welfare cost of the social security tax increases with people's degree of myopia. These results suggest that correcting myopia is not a clear rationale for the PAYG social security. 相似文献