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1.
自然保护地在维持生态平衡,实现生态系统服务功能中可以发挥重要作用,但不同类型自然保护地的主导生态系统服务功能供给存在一定差异.《自然保护地法》立法工作须依赖理论上对自然保护地的类型化,并在此基础上建构对应型的规划建设、运营管理等方面的具体制度.因此,基于生态系统服务功能供给的空间差异,可以将当前相互重叠、缺乏体系的自然保护地划分为国家公园、自然保护区、自然公园、自然保护小区等四种类型,搭建"1部基础法律+4部类型化条例(或法律)"的自然保护地法律体系,并可以通过体系化公法、私法制度工具强化自然保护地的有效治理.  相似文献   
2.
文章的特色和理论意义在于,尝试量化"一带一路"沿线18个省份"一带一路"相关政策文件,以设计政策效力、政策措施与政策保障的评判要点为基础,确定政策措施强度和政策保障强度.细致讨论"一带一路"文件的政策强度与经济开放度提升之间的关系,并讨论该关系在东西部地区的差异以及政策保障强度在政策措施强度与经济开放度关系之中的调节效应.研究发现:政策措施强度能够正向促进省域经济开放度的提升;在经济开放度高于10%的省份中,政策保障强度正向调节政策措施强度与经济开放度提升之间的关系,政策措施强度和政策保障强度之间存在互补关系;政策措施强度中资金融通强度对于沿线省域经济开放度的提升有着最显著的正向影响,政策沟通强度对于沿线省域经济开放度的提升影响不显著;政策措施强度对省域经济开放度的提升存在地区差别,西部地区更注重"一带一路"倡议所带来的机会.建议:"一带一路"沿线省份在政策设计上,不仅要对政策沟通、设施联通、贸易畅通、资金融通和民心相通等内容作出合理规划和布局,还应对保障机制作出可操作性的安排.  相似文献   
3.
针对决策信息为毕达哥拉斯模糊集的多属性决策问题,提出了一种基于混合加权测度的TOPSIS决策方法。在分析了现有距离测度方法不足的基础上,首先给出了一种新的毕达哥拉斯模糊距离测度——毕达哥拉斯模糊有序加权距离(PFOWD),并研究了该测度权重的确定方法;在PFOWD基础上,进一步提出了毕达哥拉斯模糊混合加权距离(PFHWD),同时探讨了其特征和与现有毕达哥拉斯模糊测度的关系;最后提出了一种基于PFHWD测度的毕达哥拉斯模糊TOPSIS多属性方法,并用实例验证了方法的有效性和可行性。  相似文献   
4.
Financial stress index (FSI) is considered to be an important risk management tool to quantify financial vulnerabilities. This paper proposes a new framework based on a hybrid classifier model that integrates rough set theory (RST), FSI, support vector regression (SVR) and a control chart to identify stressed periods. First, the RST method is applied to select variables. The outputs are used as input data for FSI–SVR computation. Empirical analysis is conducted based on monthly FSI of the Federal Reserve Bank of Saint Louis from January 1992 to June 2011. A comparison study is performed between FSI based on the principal component analysis and FSI–SVR. A control chart based on FSI–SVR and extreme value theory is proposed to identify the extremely stressed periods. Our approach identified different stressed periods including internet bubble, subprime crisis and actual financial stress episodes, along with the calmest periods, agreeing with those given by Federal Reserve System reports.  相似文献   
5.
针对目前金属疲劳裂纹扩展检测方法存在效率低、操作繁琐、精度不高,不能实现实时性等缺点,文章提出了基 于机器视觉的裂纹检测方法。根据金属疲劳裂纹扩展试验过程中裂纹图像的采集要求,设计了摄像头位置可自动调整 的疲劳裂纹图像采集系统,包括摄像头安装运动装置,裂纹图像采集装置以及摄像头运动控制系统。图像采集装置由高 分辨率黑白面阵CCD摄像头、光学镜头,光源照明装置和图像采集卡组成,前3者安装在摄像头支架上,与摄像头运动 装置相连。摄像头运动装置中的X,Y,,Z轴运动机构由步进电机带动滚珠导轨机构。在基于ARM技术的运动控制系统 的控制下摄像头可沿X,Y,,Z轴作高精度直线运动,实现和试件之间精确位置的调整。实验结果表明,所设计的系统可 采集到疲劳裂纹扩展试验过程中高清晰度、高分辨率的试件裂纹图像,满足下一步裂绞尺寸计算的要求;摄像头运动定 位精度可达到0. 02 mm,满足精确的系统聚焦、位置调整、跟踪采集的要求。  相似文献   
6.
A conformance proportion is an important and useful index to assess industrial quality improvement. Statistical confidence limits for a conformance proportion are usually required not only to perform statistical significance tests, but also to provide useful information for determining practical significance. In this article, we propose approaches for constructing statistical confidence limits for a conformance proportion of multiple quality characteristics. Under the assumption that the variables of interest are distributed with a multivariate normal distribution, we develop an approach based on the concept of a fiducial generalized pivotal quantity (FGPQ). Without any distribution assumption on the variables, we apply some confidence interval construction methods for the conformance proportion by treating it as the probability of a success in a binomial distribution. The performance of the proposed methods is evaluated through detailed simulation studies. The results reveal that the simulated coverage probability (cp) for the FGPQ-based method is generally larger than the claimed value. On the other hand, one of the binomial distribution-based methods, that is, the standard method suggested in classical textbooks, appears to have smaller simulated cps than the nominal level. Two alternatives to the standard method are found to maintain their simulated cps sufficiently close to the claimed level, and hence their performances are judged to be satisfactory. In addition, three examples are given to illustrate the application of the proposed methods.  相似文献   
7.
8.
以风险理论审视非物质文化遗产的现行法律制度,根据风险产生根源不同,非物质文化遗产保护的制度风险会表现为制度运转失灵风险、制度功能偏差风险和公平性缺失风险。化解制度风险,形成制度风险的维度,不可基于同一个标准,而是需要在大的框架之下论及制度风险的法律管控,需要有针对性地创构"建立私权,善用公权"的多元法律控制体系,并在体系内引入技术规制,创设"非物质文化遗产权",推动民间习惯法与法律制度、公法与私法的互动式发展。  相似文献   
9.
This study investigates the extent to which formal governance mechanisms such as contracts and equity ownership affect interfirm coordination and partnership performance. We analysed data from a survey of 301 Korean firms to show that interfirm coordination partially mediates the relationship between contract completeness, defined as the extent to which a contract specifies task operations and contingencies, and partnership performance. Furthermore, we find that more complete contracts can attenuate the negative effects of equity ownership on coordination, and that this effect is particularly strong when partner tasks are interdependent and relational norms are weak.  相似文献   
10.
The socio-economic literature has focused much on how overall inequality in income distribution (frequently measured by the Gini coefficient) undermines the “trickle down” effect. In other words, the higher the inequality in the income distribution, the lower is the growth elasticity of poverty. However, with the publication of Piketty’s magnum opus (2014), and a subsequent study by Chancel and Piketty (2017) of evolution of income inequality in India since 1922, the focus has shifted to the income disparity between the richest 1% (or 0.01%) and the bottom 50%. Their central argument is that the rapid growth of income at the top end of millionaires and billionaires is a by-product of growth. The present study extends this argument by linking it to poverty indices in India. Based on the India Human Development Survey 2005–12 – a nationwide panel survey-we examine the links between poverty and income inequality, especially in the upper tail relative to the bottom 50%, state affluence (measured in per capita income) and their interaction or their joint effect. Another feature of our research is that we analyse their effects on the FGT class of poverty indices. The results are similar in as much as direction of association is concerned but the elasticities vary with the poverty index. The growth elasticities are negative and significant for all poverty indices. In all three cases, the disparity between the income share of the top 1% and share of the bottom 50% is associated with greater poverty. These elasticities are much higher than the (absolute) income elasticities except in the case of the poverty gap. The largest increase occurs in the poverty gap squared – a 1% greater income disparity is associated with a 1.24% higher value of this index. Thus the consequences of even a small increase in the income disparity are alarming for the poorest.  相似文献   
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