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101.
为了研究网架结构的损伤检测方法,根据应变能密度理论,提出采用单元模态应变能密度差值作为网架结构损伤识别指标的方法,以损伤单元模态应变能密度差值的大小初步确定单元的损伤程度。分析了5种具有代表性的损伤工况,并在数值计算结果中引入了白噪声。结果显示,在一阶模态下,针对单损伤、多损伤和轻微损伤、严重损伤等不同损伤工况,损伤杆件的模态应变能密度差值均为高值。因此,该方法可以有效识别出网架结构的损伤位置,根据损伤单元的模态应变能密度差值大小初步确定单元的损伤程度,且在一定的噪声水平下具有较强的鲁棒性,对网架结构损伤识别具有参考价值。  相似文献   
102.
[目的]通过对全国丘陵山区县(市)与农机化有关的社会、经济和自然条件等因素进行调研所获取的238个有效样本进行分析,研究影响我国丘陵山区农机化水平的因素及其贡献,进而对我国丘陵山区进行区域划分。[方法]运用线性回归法对影响丘陵山区农机化水平的影响因素进行分析,进而对农机化水平产生显著影响的因素进行聚类分析。[结果]国内生产总值、农业劳动力数量对农机化水平产生极显著影响,耕地禀赋条件、务工工资、耕地规模、农机合作社数量和农机推广人员数量对农机化水平产生显著影响。对我国丘陵山区农机化水平呈正相关关系的因素有国内生产总值、务工工资、耕地规模、农机合作社数量,呈负相关的因素有耕地禀赋条件、农业劳动力数量、农机推广人员数量和农机化水平。[结论]我国可丘陵山区划分为中西、东南部地区,北部地区和东部沿海地区3大类地区。  相似文献   
103.
为改善借款方的长期整体发展效果,金砖国家新开发银行对其环境和社会安全保障政策框架进行了大胆创新,着力推进借款方"本国体系"的使用和建设。传统多边开发银行的环境和社会安全保障政策往往采取施加于所有借款方国家法律之上"一刀切"的方式,但难以取得理想的发展效果,其主要原因有:无法影响非多边开发银行资助项目;条件过于僵化,导致部分借款方转而求助于其他融资选项;给借款方造成沉重的时间和费用负担。"本国体系"有效克服了上述难题,但也存在相应挑战。为应对挑战,未来金砖国家新开发银行推进借款国"本国体系"的努力方向是:为本国体系预设一个最低标准;逐步有序而非一步到位地推进本国体系;切实加大对借款方的技术援助。  相似文献   
104.
研究目的:对耕地占补平衡的发展阶段与政策绩效、存在问题与逻辑根源进行分析,对改进方式进行探讨,进而提出管理创新建议,为新时代耕地占补平衡政策实施提供科学依据,为促进城乡融合、扶贫攻坚和乡村振兴提供参考。研究方法:综合分析与系统推理。研究结果:(1)耕地占补平衡存在实质性不平衡、时空性不平衡、政策性弱化等微观、中观及宏观层面问题;(2)在数量方面,通过盘活宅基地增量、存量和完善易地调剂方式,统筹城乡和区域平衡来实现数量占补平衡。(3)在质量方面,通过优化建设用地约束指标、完善耕地质量评价、规范耕作层保护与再利用等促进耕地质量占补平衡。(4)在生态方面,通过完善指标调剂的价格内涵、扩大耕地补偿标准范围、转变耕地补充途径等实现耕地生态占补平衡。研究结论:建议做好顶层设计,抓好规划引领,构建耕地占补平衡与城乡要素流动的平衡机制,建立耕地占补平衡后续生态管护长效机制,提升软硬实力等。  相似文献   
105.
以六安职业技术学院旅游管理实训中心为例,探讨在建设地方技能型高水平大学的过程中,如何来建设与管理校内实训室。  相似文献   
106.
We analyze the implications of transboundary pollution externalities on environmental policymaking in a spatial setting, in which pollution diffuses across the global spatial economy independently of the specific location in which it is originally generated. This framework gives rise to a simple regional optimal pollution control problem allowing us to compare the global and local solutions in which, respectively, the transboundary externality is and is not taken into account in the determination of the optimal policy by individual local policymakers. We show that it is not obvious that transboundary externalities are a source of inefficiency per se since this is strictly related to the spatial features of the initial distribution of pollution. If the initial pollution distribution is spatially homogeneous then the local and global solutions will coincide and thus no efficiency loss will arise from transboundary externalities, but if it is spatially heterogeneous the local solution will be suboptimal and thus a global approach to environmental problems will be needed to achieve efficiency. From a normative perspective, in this latter (and most realistic) case we also quantify the amount of policy intervention needed at local level in order to achieve the globally desirable goal of pollution eradication in the long run. Our conclusions hold true in a number of different settings, including situations in which the spatial domain is either bounded or unbounded, and situations in which macroeconomic–environmental feedback effects are taken into account.  相似文献   
107.
By integrating the two areas of competition–performance and environment–performance, this research explores if competition matters in the relationship between environmental practices and interest margins in the market. A panel of 458 banks from 74 countries for the period of 2006–2016 is used, and the sample is further divided into developed and developing countries. This paper uses the system Generalized Method of Moments estimator to tackle potential omitted variable bias, endogeneity, and simultaneity issues. Without competition, environmental practices only affect banks in developing countries; however, the results show a significant impact for the full sample, including developed countries, when the competition is taken into consideration, suggesting that competition might play a role in the relationship of environmental practices and interest margins. In the full sample, competition impacts the relationship negatively after a moderate level of competition is reached in the market. The environmental practices in developing countries are prone to competition in the market. In developed countries, the competition is found to be lightly positively moderating the impact of environmental practices on interest margins. Based on these findings, it is recommended that developing countries should have a low or moderate level of competition to encourage environmental practices. For developed countries, however, high competition should be preferred to encourage banks to consider environmental practices as one of their core business strategies. These findings are found robust to different statistical estimators.  相似文献   
108.
Abstract

The Single Supervisory Mechanism (SSM) is an administrative arrangement of national assistance to the ECB in exercising its exclusive supervisory competence. It sets two systems of assistance: ECB Direct Supervision (for large banks) and Indirect Supervision (for smaller and medium-sized banks) supervision. This paper analyzes dynamics between the ECB Banking Supervision as the principal and NCAs as its agents in the system of ECB Indirect Supervision. It identifies six formal (statutory) accountability and control mechanisms which are put at the ECB’s disposal to monitor the way how the NCAs carry SSM supervisory tasks when exercising the ECB’s exclusive supervisory competences under the SSM Regulation.  相似文献   
109.
In this paper, we generalize recursive utility to include lifetime uncertainty and utility from bequest. The generalization applies to discrete-time as well as continuous-time recursive utility, and it is an important step forward in the development of recursive utility. We formalize the problem of optimal consumption, investment, and life insurance choice under recursive utility, and we state a verification theorem with a generalized Hamilton-Jacobi-Bellman equation. Our generalization of recursive utility allows us to study optimal consumption, investment, and life insurance choice under separation of (market) risk aversion, elasticity of inter-temporal substitution, and elasticity of substitution between bequest and future utility. The separation gives rise to hump-shaped consumption patterns as observed in realized consumption.  相似文献   
110.
Swedish census data and tax records reveal an astonishing decline in the aggregate skill premium of 30 percent between 1970 and 1990, with only a modest recovery in the next couple of decades. In contrast, the US skill premium rose by around 24 percent over those four decades. A theory that equalizes wages with marginal products can rationalize these disparate outcomes when we replace commonly used measures of total labor supplies by private sector employment. The dramatic decline in the skill premium in Sweden is the result of an expanding public sector that has disproportionately hired unskilled labor.  相似文献   
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