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1.
自然资源规划评估在实践探索中形成了一套“三期十步法”的评估模式。文章以总结国内外规划评估经验为基础,具体阐述自然资源“十三五”规划评估开展的基本内容和任务,并结合实践中存在的突出问题,提出完善“十四五”规划评估的建议:一是推动自然资源规划评估标准化建设;二是构建完善的评估数据信息系统;三是建立良好的评估运行监测机制;四是加大规划评估的宣传引导。  相似文献   
2.
REITs draw attention from investors around the world, yet our understanding of the various risks associated with such securities is limited. Using the introduction of Arrowhead, a low-latency high-frequency trading platform, to the Tokyo Stock Exchange and the financial crisis of 2008 as natural experiments, we compare the resilience of REITs and equities in terms of liquidity and volatility. The results indicate that the introduction of Arrowhead improved the quality of the Japanese REIT market but also increased the probability of flash crashes. We also find that although the financial crisis significantly deteriorated overall equity market quality, the Japanese REIT market was resilient. Finally, using a difference-in-differences regression model, we show that the higher transparency and better price discovery of REITs, compared to non-REITS, protected them from the negative effects of the financial crisis and the introduction of Arrowhead. Overall, our analysis shows that REITs are more resilient than non-REITs.  相似文献   
3.
This paper deals with a fundamental subject that has seldom been addressed in recent years, that of market impact in the options market. Our analysis is based on a proprietary database of metaorders—large orders that are split into smaller pieces before being sent to the market—on one of the main Asian markets. In line with our previous work on the equity market [Said, E., Bel Hadj Ayed, A., Husson, A. and Abergel, F., Market impact: A systematic study of limit orders. Mark. Microstruct. Liq., 2018, 3(3&4), 1850008.], we propose an algorithmic approach to identify metaorders, based on some implied volatility parameters, the at the money forward volatility and at the money forward skew. In both cases, we obtain results similar to the now well-understood equity market: Square-Root Law, Fair Pricing Condition and Market Impact Dynamics.  相似文献   
4.
基于2011~2017年我国A股重污染型上市公司经验数据,实证检验了领导干部自然资源资产离任审计对企业绿色并购行为的影响,研究发现:领导干部自然资源资产离任审计可显著促进辖区内企业实施绿色并购;而当地区市场竞争程度越高时,越会抑制企业在领导干部自然资源资产离任审计试点实施背景下的绿色并购扩张行为;进一步地,企业绿色并购会显著提高企业价值,且这一影响对并购后当年的企业价值影响最为显著;基于异质性分析方面,领导干部自然资源资产离任审计会约束不同产权性质企业的环境治理行为,促进其采取绿色并购,实施绿色发展;同时领导干部自然资源资产离任审计会更有利于东部地区企业实施绿色并购,而对中西部地区的企业影响不明显。  相似文献   
5.
In the U.S., virtually no new coal-fired power plants have been built in recent years. Both industry experts and academics seem to believe that no rational firm will build a new coal-fired plant. Will such a trend continue in the future? To provide insights into this question, we investigate the optimal decision of an electricity company with an irreversible and deferrable opportunity to build either a new coal-fired or natural gas-fired power plant as its new base-load resource. According to our real option analysis, the optimal decision depends on the location. In the case of the eastern U.S., it is optimal to choose a natural gas plant if a firm is given a choice among a new natural gas plant, a new coal plant and deferring the investment. However, contrary to the common sentiment in the industry and academia, building a new coal plant in the western U.S. is still more economical than building a new natural gas plant in the absence of emission pricing. Furthermore, introducing carbon pricing to western U.S. states, as California did, can substantially increase the probability that a firm will optimally choose a natural gas plant over a coal plant.  相似文献   
6.
目的 以倪绍祥先生土地评价思想概括和我国土壤普查、土地类型述评为依据,探讨我国耕地评价工作完善路径和方向。方法 文章采用文献研究和对比分析方法。结果 (1)倪先生经过多年研究实践,形成以土壤调查为前提的,土地类型单元为基础,开展土地评价的系统思想。(2)我国土壤调查、土地类型工作中断,致使农用地分等定级、土地质量地球化学等工作缺乏扎实的数据基础,使得现有的耕地评价成果难以满足新时代耕地资源“三位一体”保护要求,也妨害国家对自然资源的科学管理。(3)国家生态文明建设、国土资源科技创新和自然资源管理机构职责整合等宏观背景,客观上要求将土地评价与土壤类型、土地类型相联系,夯实耕地评价的科学基础,创新耕地质量评价体系。(4)科学组织第三次土壤普查,服务于耕地评价实践,将土壤资源融入自然资源统一管理成为必然趋向。结论 倪绍祥先生有关土地评价思想,对于完善我国土地评价理论和方法体系,创新性开展第三次土地利用现状调查中的耕地质量调查专题,适应自然资源统一管理新形势具有重要借鉴价值。亟需科学组织新的土壤普查和土地类型调查研究,更新完善原有的土壤资源图和报告,深化中小尺度的土地类型调查研究,不仅深化人们对土地资源的客观认识,也为新的耕地质量评价提供客观、科学、高精度的数据基础提供可能。  相似文献   
7.
针对双站定位涉及的跳频信号多普勒频差估计问题,提出了归一化的频差最大似然估计算法,利用两个定位站接收到的跳频脉冲串信号,构建一个关于基准跳频频率多普勒频差的似然函数,通过网格搜索得到使似然函数最大的多普勒频差估计,既解决了跳频信号在不同跳频频率上多普勒频差不一致的问题,又充分利用在不同频率的脉冲串信号提高了多普勒频差估计精度。通过仿真对算法的性能进行了评估,结果表明,与基于子空间的算法比较,在脉冲数达到240个时,所提算法执行效率提升30%以上。  相似文献   
8.
自然资源资产管理:理论逻辑与改革导向   总被引:1,自引:0,他引:1  
研究目的:针对自然资源资产管理的理论诠释不清、改革导向不明、自然资源的资产属性尚未充分体现等问题,本文立足新时代党和国家机构改革背景,分析自然资源资产管理的理论逻辑,明确未来自然资源资产管理的改革方向。研究方法:文献研究法,综合分析法。研究结果:新时代自然资源资产管理应当基于"权利—价值—经营—管理"的理论逻辑体系框架,其中自然资源资产权利应当包含自然资源资产所有权、资格权、使用权和管理权等对象内涵,以完整、明晰和稳定作为权利实现要求;自然资源资产价值显化应当基于生态、经济等价值的全面认知,针对不同资产类型分类采用不同价值评估方法,完善市场培育、价值调节和公平分配机制;自然资源资产经营既要保障粮食安全、生态安全和规避可能风险,又要实现高品质利用,因而应当以底量保安全,以存量、数量、质量、差量和流量保协同,优化完善编制资产负债表;自然资源资产管理则应当打破自然资源资产管理割裂的现状,实现系统统一管理并建立全平台、全过程、全资源和全空间的综合监督机制。研究结论:自然资源资产管理应以"三维立体多权化"、"生态价值具象化"、"安全品质六量化"和"系统监管综合化"为改革导向,以期全面推进未来多维、绿色、高效、安全、品质、有序的自然资源资产管理方式的切实实现。  相似文献   
9.
In recent years there is a trend of consuming natural products for a sustainable and healthier life. Therefore, firms began aligning their strategy with sustainability by communication strategies that they produce natural products, which are better for health as well as the environmental sustainability. However, sometimes these claims may be deceptive. The purpose of this paper is to understand the consumers' purchasing intentions toward products claiming naturalness in their advertising and packaging strategies. This research also examined greenwashing perceptions and their potential roles in purchasing intentions. In‐depth face‐to‐face interviews carried out with 20 Turkish women regarding personal care products (local brand and international brand). The findings of the interviews revealed eight themes (perceived greenwashing, perceived green image, price perception, environmental concern, green trust, skepticism, perceived risk, and purchase intention). This study contributes to predict a framework from consumer viewpoint for identifying the themes related to greenwashing.  相似文献   
10.
Farmers in the Vietnamese Mekong Delta face a wide range of climate-related and hydrological factors which threaten rice production. Smallholder farmers must adapt to climate change to sustain rice production as their central and most important livelihood activity. A sample was stratified across agro-ecological areas in the Delta affected by flooding, alluvial soils, acid sulphate soils, and saline water intrusion and by derived farmer typologies. A rural livelihoods approach was used in focus group discussions and in-depth interviews to identify and enumerate enabling and constraining adaptation factors. Smallholders experienced diverse natural hazards such as floods, abnormal rains, high temperatures, water scarcity, and salinity intrusion specific to the agro-ecological areas. Adaptation was constrained by labour shortages, water quality, topography, access to combine harvesters, transportation infrastructure, dryers and household savings. Adaptation was enabled by farming techniques and experience, cooperative groups, water quantity, access to information, and ability to purchase agro-chemicals through credit. Small farmers (< 1?ha) were more constrained than large farmers (> 1?ha) who had an expanded livelihood asset base. A range of policy implications are discussed, but adaptation is not just about technological fixes but requires overall improvements in a range of human, social and financial components.  相似文献   
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