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91.
Despite longstanding research on the landslide hazard assessment and mapping, the use this information in regional planning applications remains largely unclear. There is still a need for novel methods to interpret the results of hazard analyses. In this respect, the main research question of this study is how the landslide hazard maps can be evaluated in planning practice. To evaluate this issue, a comprehensive case study was carried out and a new methodology, defining the order of priority for the locations where mitigation measures are applied was developed. The investigations were carried out in the Melen Dam reservoir, which provides potable water to the city of Istanbul, and the dam protection area (Duzce, Turkey) in four main stages: (i) Evaluation of the general characteristics of the study area, (ii) preparation of landslide inventory, (iii) development of landslide hazard model, and (iv) implementation of the results of hazard analyses in planning. As a consequence, a decision support system that can evaluate analytically complicated outputs “PCombined”, “PAL min.”, and “LTotal” and provide clear decisions “Urgent”, “Primary”, and “Secondary” was suggested. Considering the limited resources available for the mitigation measures, the determination of mitigation priorities for the micro-catchments constitutes the key land-use policy for the protection of the dam reservoir.  相似文献   
92.
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   
93.
Absentee landowners, or those who do not live on their forestland, own approximately 117 million acres of private forestland in the U.S. Thus, their land management decisions and activities influence the flow of forest-based goods and services. We explore the question of whether absentee family forest owners are less active land managers than resident landowners and whether membership in conservation organizations is associated with higher levels of land management activity by absentee owners. To examine these questions, we administered a mail survey to randomly-selected family forest landowners in Indiana. While we found some support for the contention that absentee owners are less active forestland managers than resident owners, we also found they are not necessarily inactive landowners. We found absentee owners were less likely to have: inspected their forestland for invasive plants, pulled or cut invasive plants, used herbicides to kill invasive plants, reduced fire hazard, or grazed livestock than resident owners. Absentee owners were more likely to be enrolled in the Indiana Classified Forest and Wildlands Program, a preferential forest property tax program. Absentee owners who are members of a conservation organization were more likely than absentee non-member owners to have undertaken a variety of land management activities, including: undertaking wildlife habitat improvement projects, inspecting their forestland for invasive plants, pulling or cutting invasive plants, enrolling in the Indiana Classified Forest and Wildlands program, and obtaining a management plan.  相似文献   
94.
We examine whether professional forecasters incorporate high-frequency information about credit conditions when revising their economic forecasts. Using a mixed data sampling regression approach, we find that daily credit spreads have significant predictive ability for monthly forecast revisions of output growth, at both the aggregate and individual forecast levels. The relationships are shown to be notably strong during ‘bad’ economic conditions, which suggests that forecasters anticipate more pronounced effects of credit tightening during economic downturns, indicating an amplification effect of financial developments on macroeconomic aggregates. The forecasts do not incorporate all financial information received in equal measures, implying the presence of information rigidities in the incorporation of credit spread information.  相似文献   
95.
I propose applying the Mixed Data Sampling (MIDAS) framework to forecast Value at Risk (VaR) and Expected shortfall (ES). The new methods exploit the serial dependence on short-horizon returns to directly forecast the tail dynamics of the desired horizon. I perform a comprehensive comparison of out-of-sample VaR and ES forecasts with established models for a wide range of financial assets and backtests. The MIDAS-based models significantly outperform traditional GARCH-based forecasts and alternative conditional quantile specifications, especially in terms of multi-day forecast horizons. My analysis advocates models that feature asymmetric conditional quantiles and the use of the Asymmetric Laplace density to jointly estimate VaR and ES.  相似文献   
96.
I consider the problem of determining an equitable and efficient allocation of resources in production economies with factors which must be dedicated to production and cannot be consumed directly. First, I show that in such economies envy-free and efficient allocations exist under standard assumptions. However, I argue this notion of fairness is unsuitable for the present context. I then introduce a new notion of fairness, which I call resource-envy-freeness. First, I associate with each consumption bundle its resource footprint consisting of the vector of factors used to produce it. I then show that preferences over consumption bundles can be extended to preferences over factor bundles. An allocation is resource-envy-free if no agent prefers another agent’s resource footprint to its own. The analysis of resource-envy-free allocations in production is exactly analogous to the analysis of envy-free allocations in exchange. I establish that resource-envy-free and efficient allocations exist under standard assumptions, and I demonstrate that such allocations are intuitively appealing.  相似文献   
97.
This study explores the effect of environmental, social, and governance (ESG) performance on market value and performance in the context of mergers and acquisitions. We examine whether acquisition of targets with better ESG performance can help acquirers to increase their own ESG performance and whether the market values the increased ESG performance positively. Moreover, we explore whether the acquisition of targets with better ESG performance affects the market value of acquirers. For this study, we utilize a sample of 100 European mergers and acquisitions between 2003 and 2017, for which matching data on the ESG performance of both the target and acquiring firms are available. Our results show that the postmerger ESG performance of the acquirer increases following the acquisition of a target that has higher ESG performance than that of the acquirer in the premerger stage, whereas the postmerger market value of the acquirer increases following an increase in the acquirer's postmerger ESG performance in relation to its premerger ESG performance. Finally, we provide partial evidence of a positive relationship between the postmerger market value of the acquirer and the acquisition of a target with higher ESG performance than itself in the premerger stage.  相似文献   
98.
Institutional investors show increasing interest in how companies align their corporate social responsibility strategies with the sustainable development goals (SDGs) proposed by the United Nations (UN). The information disclosed in this regard is essential to know and monitor business contribution to the 2030 Agenda. In this paper, we analyze the influence that institutional investors have on the adoption of the disclosure strategy established by UN and the Global Reporting Initiative (GRI)—GRI‐SDG Compass. The results obtained for a sample of 989 international companies, which prepare their sustainability reports following the GRI guidelines, show that ownership by foreign investors, pension funds, and “other” investors boosts the relevance of the information disclosed in relation to the 2030 Agenda. On the contrary, government, financial institutions, and cross holdings have no impact on the information systems developed.  相似文献   
99.
为进一步提升中短码长下准循环低密度奇偶校验(Quasi-cyclic Low-density Parity-check,QC-LDPC) 码的纠错性能,提出了一种综合短环数目和环连通性的QC-LDPC码构造方法。首先,采用Golomb规则构造QC-LDPC码,对基矩阵中的部分元素进行替换预处理,初步降低短环数目;其次,采用所提的利用近似环外信息度(Approximate Cycle Extrinsic message degree,ACE)的消环掩模算法来优化QC-LDPC码,使得掩模后的校验矩阵具有较大的ACE平均值,最终完成QC-LDPC码的构造。该构造方法简单、通用性强,在短环数目和连通性间进行了平衡。与只考虑减少短环数目、增大围长等方法相比,该方法构造的QC-LDPC码有更加优异的纠错性能。  相似文献   
100.
新冠疫情的暴发以及长期防治对中国的公共卫生体系造成深远影响,给我国突发公共卫生事件应急与防控机制带来巨大的考验。在疫情防控的过程中,信息化技术为传统医疗机构带来瞩目的帮助与改变,人工智能、大数据、5G高速网络等新兴高科技的蓬勃发展在直接提升医疗水平方面表现出巨大潜力。本文就人工智能在疫情期间的医疗辅助功能展开讨论,并对未来我国公共卫生体系的建设进行了思考。  相似文献   
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