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11.
Since the beginning of the 21st century, China has undergone a promotion of industrialisation, urbanisation and agricultural modernisation. This promotion has triggered the mass migration of rural labour forces into cities, leading to the virtual situation of the separation of farmland contract and operation rights. To respond to this issue, the central government proposed a strategy of farmland reform in China. Such reform aims to transform the former ‘Bipartite Entitlement System’ into a ‘Tripartite Entitlement System (TES)’.1 Land registration provides the means for recognising formalised property rights and regulating the characteristics and transfer of land-related rights. As for farmland registration in China, it serves as a basis to explore effective forms of collective farmland ownership by implementing collective farmland ownership, stabilising farmers’ contract rights and liberalising farmland operation rights. Thus, in this study, on the basis of the farmland tripartite entitlement (hereinafter referred to as ‘FTE’) reform in China, we develop a Land Administration Domain Model (LADM)-based TES model that will serve as the basis of subsequent system development. Specifically, first, we summarise the evolution process of China’s farmland rights system since the foundation of new China. Second, we propose a farmland rights system after the FTE reform. Then, the corresponding TES model is developed based on the LADM standard and some instance-level diagrams for farmland administration activities. The new functionality of the model includes improved structuring of farmland rights and restrictions (and related source documents) and improved expansion of the land information infrastructure to rural areas. 相似文献
12.
This paper deals with precision farming tools (PFTs), a way of farming which relies on specialized equipment, software and information technologies services, whose importance is underlined in recent documents of the European Union. Precision farming is an integrated and sustainable farm management system making use of modern technologies to increase farm’s profitability, by reducing environmental impact. In this paper we explore the complex mechanisms that affect PFT’s adoption by Italian farmers. More precisely, we try to analyse the context-related factors affecting adoption of PFTs in the Italian farms.Little research has been carried out in Italy on this topic, therefore our paper tries to fill a gap in literature. In order to investigate the process of technology adoption related to precision agriculture, a questionnaire was submitted to a sample of Italian farms. The questionnaire has been structured in order to apply the AKAP (Awareness, Knowledge, Adoption, Product) sequence. Our analysis underlines that context-related factors are fundamental dimensions to be explored in order to specify uptake of PFTs. Therefore, the paper has relevant policy implications, within the context of a new participatory approach to agricultural innovation characterized by bottom-up processes boosted by farmers, which has informed the recent policies of agricultural innovation at the EU level. 相似文献
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14.
提出了一种新型的Ka频段圆极化相控阵天线。天线单元以单馈电开槽贴片天线为基础实现圆极化,通过微带贴片表面加载介质和辅助辐射器,展宽了天线波束宽度并优化了单元轴比。以该天线为阵列单元,采用顺序旋转布阵技术优化得到的2×2子阵,其辐射方向图具有良好的旋转对称性,由该子阵扩展形成的相控阵天线,有效地实现了圆极化宽角扫描特性。以8×8矩形阵列为例,仿真分析了此类二维相控阵天线波束扫描过程中的方向图和极化特性。研究结果表明,天线在工作频段内可实现方位360°、俯仰±60°扫描,扫描范围内天线增益波动和轴比均小于3 dB,同时该天线具有低剖面(高度尺寸为0.08λ0,λ0为空气介质波长)、结构简单、易于加工和集成等特点,非常适合小型化或一体化相控阵天线系统应用。 相似文献
15.
长期以来,人们只看重货币国际化结果,以占全球贸易计价结算比重、外汇交易比重、国际债券比重、外汇储备比重等相关指标衡量一国货币的国际化程度,而忽视货币跨境流动放松过程,即一国货币的跨境流动自由化程度。货币国际化是一个过程又是一种结果,包含进程和结果两个层面,在货币国际化进程中,过早过快放松本币流出入会引发经济金融风险,某些情形下进程比结果更值得关注。构建人民币跨境自由度指数涉及强度赋值、项目设置和权重确定三方面内容。在梳理2019年第2季度前我国货币政策基础上,对2008年至2019年经常项目下的人民币跨境流动自由度、证券投资项目下的人民币跨境流动自由度以及资本项目下的人民币跨境流动自由度进行评估,并以美国近5年各项目下的资金流动平均占比为权重,构建了人民币跨境流动自由化指数,考察2008—2019年人民币跨境流动自由化程度,结果显示人民币国际化进展较快,跨境流动已得到很大程度放松,而且人民币流入自由程度显著高于流出自由度。我国人民币国际化进程应持续遵循先经常项目后资本项目、先流入后流出、先机构后个人、先大额后小额、先风险小项目后风险大项目的次序,提高人民币跨境流动的稳定性,降低无序流动的投机风险;严格管控证券投资、其他投资、衍生品项目下人民币跨境流动,并依据我国利率市场化程度、金融市场发达程度及审慎监管能力进行调整;大力提升经常项目的人民币结算比重,发展人民币离岸市场,提高非居民间的人民币使用频率和使用规模;充分评估各项目下人民币跨境流动和本外币兑换自由度,提高两者的协同匹配程度,降低因两者不匹配而产生的负面影响。 相似文献
16.
微表情是人们处在一些与平时生活环境不同的高强度环境下试图控制和掩饰的情感表现,也是一种不曾意识到的瞬时脸部表情,持续时间短,强度弱。为了提高其准确率,提出了基于Radon变换的微表情识别算法。首先,对数据库中的视频序列进行灰度归一化、尺寸归一化和二维主成分分析法(Two-dimensional Principal Component Analysis,2DPCA)降维预处理,使用光流法对降维后图像提取运动特征;然后使用Radon变换算法对光流图像进行处理,得到对应微表情的特征值和特征图像;最后使用支持向量机进行微表情分类识别。实验结果表明,使用Radon变换后得到的微表情特征图像得到了较好的识别效果,在微表情数据集CASME和CASMEⅡ上识别率分别为81.48%和82.17%,通过与选取的其他方法对比说明了该方法具有更好的识别性能。 相似文献
17.
乡村旅游是乡村振兴的有效路径,也是近年来研究热点,而在乡村旅游流领域研究相对不足。以湖州乡村旅游地为案例,通过对大样本数字足迹的数据处理,分析乡村旅游流空间结构特征,总结空间行为偏好。结果表明:①乡村旅游数字足迹呈现全年双峰值、月度差异不大的时间特征,"双核"多组团的空间分布特征,以及古镇、古村、民宿等带有文化符号旅游景观导向的空间偏好特征;②网络密度0.27的乡村旅游流空间结构由连接度高的34个节点构成,除核心吸引的双核外,民宿集聚区构成了网络结构的核心点;③传统旅游吸引物、民宿集聚区等节点呈现较强的网络中心性,节点的网络结构特征反映乡村旅游流空间呈现的地理临近性,以及区域空间集聚、扩散与联动发展效应。依据研究结论提出"完善与发挥节点集聚扩散功能,增强节点对数字足迹的有效吸引力,提升乡村旅游经济发展质量,助力乡村振兴"的发展策略。 相似文献
18.
Jeong-Ho Koo 《新兴市场金融与贸易》2018,54(1):144-161
The extant literature on behavioral corporate finance has explored the effects of overconfidence on investment–cash flow sensitivity (ICS) to explain overinvestment, yet it has overlooked the asymmetric behavior of investments in relation to changes in cash flow levels. This study examines whether investments behave asymmetrically responding to changes in cash flows and, if so, how managerial overconfidence affects asymmetric ICS. Using a sample of KOSPI and KOSDAQ firms in Korea, we find the incidence of downwardly sticky ICS in unconstrained firms. We then find that overconfident managers encourage ICS to be stickier than their rational peers do in unconstrained firms. Finally, we find that managerial overconfidence intensified by self-attribution bias induces ICS to get even stickier, suggesting more explicit evidence of corporate investment distortions. The results of alternative tests using the asymmetric models of Homburg and Nasev (2008) are qualitatively consistent with prior results. Overall, our findings imply a higher incidence of excessive investment commitments driven by overconfident managers. 相似文献
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20.
Yousra Hallem Wissal Ben Arfi Frédéric Teulon 《Canadian Journal of Administrative Sciences / Revue Canadienne des Sciences de l\u0027Administration》2020,37(1):82-94
Online collaborative consumption enhances peer networks, members of which communicate, collaborate, and even deliver services to one another via digital sharing platforms. Despite the tremendous increase in collaborative consumption, due in large part to the development of the Internet, the reality of the economic and social movements that underpin this trend is much less visible. Of course, not all consumers seek collaborative consumption or interact through online platforms. Using a qualitative approach, this paper aims to investigate motivational factors and barriers against collaborative consumption and to establish a typology of collaborative consumer profiles, identifying the most suitable type of online sharing platforms for each profile. The findings reveal the following collaborative consumer profiles: committed, pragmatists, intermittent, and skeptical, each demonstrating different preferences for the different type of online sharing platform. 相似文献