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Impact of Environmental,Social,and Governance(ESG)Factors on Stock Prices and Investment Performance
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作者 Abhinandan Kulal Abhishek N +1 位作者 Sahana Dinesh Divyashree M.S. 《Macro Management & Public Policies》 2023年第2期14-26,共13页
This study examines the relationship between Environmental,Social,and Governance(ESG)factors and stock prices as well as investment performance.ESG factors have become increasingly relevant in investment decisions as ... This study examines the relationship between Environmental,Social,and Governance(ESG)factors and stock prices as well as investment performance.ESG factors have become increasingly relevant in investment decisions as investors prioritize companies with sustainable practices.Using a sample of publicly-traded companies,this research analyzes the impact of ESG factors on stock prices and investment returns.The findings suggest that companies with strong ESG performance tend to have higher stock prices and better investment performance than those with weak ESG performance.The study also highlights the significance of the individual components of ESG,such as environmental policies and corporate governance practices,on stock prices and investment returns.Overall,this research provides valuable insights for investors seeking to incorporate ESG factors into their investment decision-making processes. 展开更多
关键词 ESG factors stock price investment performance
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基于InVEST模型和PLUS模型的三峡库区(重庆段)碳储量时空变化及预测
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作者 尹珂 廖思雨 《长江科学院院报》 CSCD 北大核心 2024年第9期60-69,共10页
分析三峡库区(重庆段)近10 a的土地利用类型及碳储量的空间格局,并模拟未来10 a不同情景下土地变化趋势、预测碳储量变化,有利于促进区域土地利用格局的优化、合理生态政策的制定。利用InVEST模型,选取13个驱动因子,分析三峡库区(重庆段... 分析三峡库区(重庆段)近10 a的土地利用类型及碳储量的空间格局,并模拟未来10 a不同情景下土地变化趋势、预测碳储量变化,有利于促进区域土地利用格局的优化、合理生态政策的制定。利用InVEST模型,选取13个驱动因子,分析三峡库区(重庆段)在2010—2020年及不同发展情景下2030年的土地利用变化趋势,并结合PLUS模型评估其碳储量状况。结果表明:①2010—2020年三峡库区(重庆段)土地利用变化主要表现为耕地、草地和湿地向林地、建设用地及水域的快速转移;2010年、2020年碳储量分别为426.89×10^(6)、425.51×10^(6) t,呈下降趋势,总量减少了1.38×10^(6) t;②碳储量分布具有空间分异性,总体表现为西低东高、南低北高、库首>库尾,碳储量空间变化与地类变化具有较高的一致性;土地利用空间格局演变的贡献度最高的驱动因素是社会经济因子,其中人口、GDP最为突出;③到2030年,自然发展情景和城镇发展情景下碳储量分别减少了0.76×10^(6)、8.98×10^(6) t,生态保护情景下增加了3.72×10^(6) t。高碳密度的地类向低碳密度地类转移是导致碳储量减少的主要原因,因此,未来应形成平衡、协调、低碳的土地利用空间格局,规划城市增长边界,重点保障巫山山系、大巴山系、武陵山系等林草高碳储量区,推行尾库区复林复草,保障库区碳汇功能。 展开更多
关键词 碳储量 三峡库区 PLUS模型 invest模型 土地利用变化
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基于PLUS-InVEST模型的呼和浩特市多情景土地利用变化动态模拟及碳储量评估 被引量:4
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作者 王子昊 王冰 +1 位作者 张宇飞 张秋良 《农业资源与环境学报》 CAS CSCD 北大核心 2024年第2期292-304,共13页
为探究呼和浩特市土地利用变化对生态系统碳储量的影响,本研究基于InVEST模型与PLUS模型模拟预测呼和浩特市在自然发展、生态保护、耕地保护、城市发展4种情景下的土地利用与碳储量。结果表明:1990-2020年呼和浩特市不透水面、林地、草... 为探究呼和浩特市土地利用变化对生态系统碳储量的影响,本研究基于InVEST模型与PLUS模型模拟预测呼和浩特市在自然发展、生态保护、耕地保护、城市发展4种情景下的土地利用与碳储量。结果表明:1990-2020年呼和浩特市不透水面、林地、草地、水体等土地利用类型的面积呈增加状态,耕地、裸地、灌木地等土地类型的面积呈减少状态,其中灌木地和裸地的土地转出率较高,分别为93.63%和98.24%。InVEST模型估算结果显示,不透水面不断扩张,侵蚀耕地等高碳密度土地类型,造成呼和浩特市1990-2020年碳储量呈逐年递减趋势。2030年自然发展、生态保护、耕地保护、城市发展情景模拟下的呼和浩特市的碳储量与2020年相比均呈现减少状态,其中耕地保护情景碳储量降幅最小,其次为生态保护情景,说明采取合理的保护措施能够有效抑制碳储量下降。耕地保护情景能够有效减缓城市建筑的扩张趋势,生态保护情景则可有效增加水体、草地等生态类用地面积。研究表明,落实耕地和生态保护政策、优化土地利用结构、提高土地利用效率对呼和浩特市的可持续发展均有重要意义。 展开更多
关键词 呼和浩特市 PLUS模型 invest模型 土地利用 碳储量
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基于InVEST模型的京津冀土地利用变化及碳储量时空分异研究 被引量:4
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作者 彭云妮 桑会勇 +2 位作者 翟亮 张紫怡 段晋江 《测绘通报》 CSCD 北大核心 2024年第1期19-24,31,共7页
大气中二氧化碳含量的增加是国际社会广泛关注的环境问题,人类活动改变土地利用格局,而土地利用/覆被(land-use/land-cover,LULC)变化影响陆地生态系统结构、功能及碳循环。本文在全球地表覆盖数据GlobeLand30的支持下分析了2000-2020... 大气中二氧化碳含量的增加是国际社会广泛关注的环境问题,人类活动改变土地利用格局,而土地利用/覆被(land-use/land-cover,LULC)变化影响陆地生态系统结构、功能及碳循环。本文在全球地表覆盖数据GlobeLand30的支持下分析了2000-2020年京津冀土地利用变化,利用InVEST模型模拟了碳储量时空变化,并结合空间自相关分析技术对其进行了分区研究。结果表明:①2000-2020年京津冀地区耕地和人造地表变化面积最大,分别为减少340222.124 hm^(2)和增加246333.493 hm^(2);②京津冀地区2000、2010和2020年碳储量总值分别为1666.47×10^(6)、1654.63×10^(6)、1632.88×10^(6)t,耕地流失和人造地表扩张是碳储量下降的主要原因;③京津冀碳储量高值主要分布在海拔相对较高的山林地区,低值主要分布在北京市中心、津冀海岸带,以及河北省沧州和唐山的东部南部区域;④局部自相关结果表明,碳储量出现高-高聚集的区域在研究区的北部和西部,在出现低-低聚集的区域中天津市东丽区和河北省邯郸市邯山区呈现出较为明显的弱化趋势。 展开更多
关键词 碳储量 土地利用 invest模型 京津冀 空间自相关分析
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基于PLUS和InVEST模型的合肥市生态系统碳储量时空演变特征 被引量:6
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作者 智菲 周振宏 +1 位作者 赵铭 王诗琪 《水土保持学报》 CSCD 北大核心 2024年第2期205-215,共11页
[目的]为寻求“双碳”目标导向下的合肥市城市发展新方案。[方法]依据合肥市2000-2020年5期土地利用数据,在合肥市国土空间规划指引下,运用PLUS模型模拟得到2035年合肥市土地利用时空演变规律,耦合InVEST模型探究多情景下合肥市碳储量... [目的]为寻求“双碳”目标导向下的合肥市城市发展新方案。[方法]依据合肥市2000-2020年5期土地利用数据,在合肥市国土空间规划指引下,运用PLUS模型模拟得到2035年合肥市土地利用时空演变规律,耦合InVEST模型探究多情景下合肥市碳储量时空变化特征,并进一步挖掘土地综合利用程度对碳储量的影响。[结果](1)2000-2020年合肥市土地利用变化特征主要表现为耕地、林地减少,其中耕地为建设用地扩增主要来源。自然发展和农田资源保护情景的土地变化规律大致相同,主要表现为耕地、林地、水体减少;绿色汇增城市发展情景下,林地相比其余2个情景面积由减少转为增加。(2)2000-2020年合肥市碳储量逐年递减,其中2005-2010年碳损失最为剧烈。到2035年,自然发展情景、农田资源保护情景、绿色汇增城市发展情景碳储量分别为138.96×10^(6),140.13×10^(6),139.81×10^(6) t。农田资源保护情景下,碳储量明显增加区域最低,建设用地扩张减缓;绿色汇增城市发展情景下,林地由碳损失转为碳固持,是最具固碳潜力的发展趋势。(3)绿色汇增城市发展情景土地利用率最高,可有效降低土地综合利用程度对碳储量流失的威胁。[结论]农田资源保护情景与绿色汇增城市发展情景均有助于城市固碳发展,实施生态保护与城市发展并行政策,调整土地综合利用模式有助于改善城市碳流失。 展开更多
关键词 invest模型 PLUS模型 碳储量 土地利用程度综合指数
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基于PLUS和InVEST模型的乌鲁木齐市碳储量时空演变与预测 被引量:2
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作者 李佳珂 邵战林 《干旱区研究》 CSCD 北大核心 2024年第3期499-508,共10页
土地利用变化对陆地生态系统的碳储量变化有着重要影响,研究不同发展情景下陆地生态系用碳储量变化情况,有利于优化空间布局,协调土地利用与生态环境保护的关系。本研究结合PLUS和InVEST模型,通过多种驱动因素数据分析了2000—2020年乌... 土地利用变化对陆地生态系统的碳储量变化有着重要影响,研究不同发展情景下陆地生态系用碳储量变化情况,有利于优化空间布局,协调土地利用与生态环境保护的关系。本研究结合PLUS和InVEST模型,通过多种驱动因素数据分析了2000—2020年乌鲁木齐市土地利用的变化特征,以此预测模拟2030年自然发展情景、生态保护优先情景和耕地保护优先情景下土地碳储量。结果表明:(1)2000—2020年乌鲁木齐市林地、水域、建设面积、未利用地数量增加,耕地、草地面积减少。(2)2030年,自然发展情景延续了以往发展模式,建设用地面积增幅为18.29%。生态保护优先情景下,建设用地的扩张速度得到有效控制,增幅已经减缓,为4.73%。耕地保护优先情景下耕地面积比自然发展情景下多了171 km^(2),耕地保护效果显著。(3)2000—2020年,碳储量呈下降趋势,共计减少8.5×10^(6)t。2030年自然发展情景下碳储量总量相较于2020年减少了4.065×10^(6)t,生态保护优先情景下比自然增长情景高7.519×10^(5)t,耕地保护优先情景比自然增长情景低1.979×10^(6)t。因此,在未来乌鲁木齐市发展规划中,应当落实耕地保护责任,控制建设用地向林地、草地等高碳密度用地的扩张,优化用地布局,提高区域碳储量水平。 展开更多
关键词 碳储量 土地利用变化 PLUS模型 invest模型
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基于PLUS-InVEST模型的福建省碳储量时空演变与预测
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作者 包靖玲 叶超杨 +2 位作者 林池源 李文 范水生 《福建农林大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期808-815,共8页
【目的】探究土地利用变化对福建省碳储量的影响,预测不同土地利用情景下的碳储量,为该区域土地规划与合理利用提供依据。【方法】基于福建省2000—2020年土地利用数据,分析2000—2020年福建省碳储量变化及其对土地利用变化的响应;采用P... 【目的】探究土地利用变化对福建省碳储量的影响,预测不同土地利用情景下的碳储量,为该区域土地规划与合理利用提供依据。【方法】基于福建省2000—2020年土地利用数据,分析2000—2020年福建省碳储量变化及其对土地利用变化的响应;采用PLUS模型预测2030年福建省土地利用格局,并用InVEST模型评估2030年碳储量。【结果】(1)2000—2020年福建省耕地面积减小了1758.44 km^(2),建设用地面积增大了3105.50 km^(2)。(2)2000—2020年福建省碳储量和碳密度均呈逐年下降的趋势,碳储量减少了13.02 Tg,碳密度降低了1.06 Mg·hm^(-2);碳储量的空间分布存在显著差异,呈西北部与中部高、东南部低的分布格局。(3)福建省碳储量多情景预测结果显示:2030年在自然演化和粮食安全情景下福建省碳储量较2020年分别减少4.27 Tg和2.12 Tg,仅在生态保护情景下增加5.29 Tg。碳储量变化的区域主要集中在山区和沿海平原。【结论】合理的土地利用规划与生态保护措施有助于提高福建省碳储量。 展开更多
关键词 土地利用变化 碳储量 PLUS模型 invest模型 福建省
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Detecting the lead–lag effect in stock markets:definition,patterns,and investment strategies 被引量:1
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作者 Yongli Li Tianchen Wang +1 位作者 Baiqing Sun Chao Liu 《Financial Innovation》 2022年第1期1478-1513,共36页
Human activities widely exhibit a power-law distribution.Considering stock trading as a typical human activity in the financial domain,the first aim of this paper is to validate whether the well-known power-law distri... Human activities widely exhibit a power-law distribution.Considering stock trading as a typical human activity in the financial domain,the first aim of this paper is to validate whether the well-known power-law distribution can be observed in this activity.Interestingly,this paper determines that the number of accumulated lead–lag days between stock pairs meets the power-law distribution in both the U.S.and Chinese stock markets based on 10 years of trading data.Based on this finding this paper adopts the power-law distribution to formally define the lead–lag effect,detect stock pairs with the lead–lag effect,and then design a pure lead–lag investment strategy as well as enhancement investment strategies by integrating the lead–lag strategy into classic alpha-factor strategies.Tests conducted on 20 different alpha-factor strategies demonstrate that both perform better than the selected benchmark strategy and that the lead–lag strategy provides useful signals that significantly improve the performance of basic alpha-factor strategies.Our results therefore indicate that the lead–lag effect may provide effective information for designing more profitable investment strategies. 展开更多
关键词 Power-law distribution Lead-lag effect stock market Complex network investment strategy
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Ratio K: a New Way of Metering and Evaluating the Risk and Return of Stock Investment 被引量:1
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作者 朱淑珍 朱静怡 《Journal of Donghua University(English Edition)》 EI CAS 2003年第2期129-136,共8页
Although widely used, both the Markowitz model and VAR (Value at Risk) model have some limitations in evaluating the risk and return of stock investment. By the analysis of the conceptions of risk and return, together... Although widely used, both the Markowitz model and VAR (Value at Risk) model have some limitations in evaluating the risk and return of stock investment. By the analysis of the conceptions of risk and return, together with the three hypotheses of technological analysis, a novelty model of metering and evaluating the risk and return of stock investment is established. The major indicator of this model , risk-return ratio K, combines the characteristic indicators of risk and return. Regardless of the form of the risk-return probability density functions, this indicator K can always reflect the risk-return performances of the invested stocks clearly and accurately. How to use the model to make optimum investment and how to make portfolio combined with clustering analysis is also explained. 展开更多
关键词 stock investment risk and return risk-return ratio K metering and evaluating
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基于InVEST和PLUS模型的江西省土地利用碳储量时空变化与预测 被引量:1
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作者 刘翰芳 刘牧 《上海国土资源》 2024年第1期86-92,共7页
土地利用变化是驱动碳储量变化的主要因素,评估土地利用变化对碳储量的影响对于碳平衡具有重要意义。以江西省为例,基于InVEST-PLUS模型,探究1990—2020年江西省土地利用变化和碳储量时空演变,测算2030年多情景碳储量。(1)江西省1990年... 土地利用变化是驱动碳储量变化的主要因素,评估土地利用变化对碳储量的影响对于碳平衡具有重要意义。以江西省为例,基于InVEST-PLUS模型,探究1990—2020年江西省土地利用变化和碳储量时空演变,测算2030年多情景碳储量。(1)江西省1990年、2000年、2010年和2020年的碳储量分别为12.7594、12.7600、12.6912、12.5800亿吨,总体呈现减少态势。林地的减少是造成碳储量损失的主要因素。地上生物量碳库和土壤碳库碳储量最多,占总碳储量的88.82%。(2)至2030年,较2020年,在自然发展与城镇发展情景下,碳储量分别减少380、1330万吨,在生态保护情景下则增加125万吨,表明采取生态保护措施,优化土地利用结构,能有效控制碳储量的减少。(3)碳储量明显较高的地区位于生态用地连片的赣南山区,而碳储量明显较低的地区位于碳密度值较低以及建设用地呈斑块状分布的赣北区域。研究结果将为江西省生态文明建设作出合理生态决策、实现高质量发展提供科学依据。 展开更多
关键词 土地利用 碳储量 invest模型 PLUS模型 变化分析
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基于InVEST模型的河池市森林碳储量估测研究 被引量:1
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作者 梁民 陈秀庭 +2 位作者 徐庆玲 曾春阳 刘峰 《林业调查规划》 2024年第4期43-50,共8页
为了探明河池市碳储量变化情况并快速评估分级,以2010年、2020年土地利用数据为数据源,研究基于InVEST模型的河池市森林碳储量估测模型的构建及其空间分布。结果表明,河池市2010和2020年碳储量分别为219.1×10^(6) t和234.8×10... 为了探明河池市碳储量变化情况并快速评估分级,以2010年、2020年土地利用数据为数据源,研究基于InVEST模型的河池市森林碳储量估测模型的构建及其空间分布。结果表明,河池市2010和2020年碳储量分别为219.1×10^(6) t和234.8×10^(6) t,呈增长趋势,碳储量在空间分布上表现为北部、中部及南部较高,西北部和东部较低的空间特征;河池市固碳能力与土地利用类型变化密切相关,林地对河池市碳储量增加贡献最大。根据河池市碳储量空间分布对全市碳储量的重要程度进行分级,更为直观地展现全市碳储量在区位上的重要程度。 展开更多
关键词 森林碳储量 碳密度 土地利用类型 invest模型 河池市
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Coupling and Long-term Change Characteristics of Forest Carbon Sink and Forestry Economic Development in China
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作者 Ying ZHANG Na MENG Keren ZHANG 《Asian Agricultural Research》 2024年第7期1-11,共11页
[Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promo... [Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promote the development of green low-carbon economy in China.[Methods]Based on the data of six forest resource inventories from 1989 to 2018 and related studies,the comprehensive evaluation model of forest carbon sink and forestry economic development,the coupling degree model of forest carbon sink and forestry economic development,and the coupling coordination degree model of forest carbon sink and forestry economic development were adopted.The coupling degree of forest carbon sink and forestry economic development from 1992 to 2018 was analyzed.Stepwise regression and ARIMA model were used to analyze the influencing factors and lagging characteristics of forest carbon sink.The coupling degree between forest carbon sink and forestry economic development in China from 2019 to 2030 was predicted by autoregression and ADF test.The coupling between forest carbon sink and forestry economic development in China and its long-term change characteristics were also discussed in this study.[Results](i)The investment of ecological construction and protection,the actual investment of forestry key ecological projects,GDP and the import of forest products had a significant impact on forest resources carbon stock.The total output value of forestry industry,the actually completed investment of forestry key ecological projects and the export volume of forest products had a significant impact on the forest carbon sink,and the actually completed investment of forestry key ecological projects has the greatest impact on the two.(ii)The impact of actually completed investment of forestry key ecological projects had a lag of 2 years on the forest resources carbon stock and a lag of 1 year on the forest carbon sink.When investing in forest carbon sink,it is necessary to make a good plan in advance,and do a good job in forest resources management and time optimization.(iii)From 1992 to 2018,the coupling degree of forest resources carbon stock,forest carbon sink and long-term development of forestry economy in China was gradually increasing.Although there were some fluctuations in the middle time,the coupling degree of forest resources carbon stock and the long-term development of forestry economy increased by 9.24%annually,and the degree of coupling coordination increased from"serious imbalance"in 1992 to"high-quality coordination"in 2018.From 1993 to 2018,the coupling degree of forest carbon sink and long-term development of forestry economy increased by 9.63%annually,slightly faster than the coupling coordination degree of forest resources carbon stock and long-term development of forestry economy.The coordination level also rose from level 2 in 1993 to level 10 in 2018.(iv)The prediction shows that the coupling coordination degree of forest resources carbon stock,forest carbon sink and the long-term development of forestry economy would increase from 2019 to 2030.The coupling coordination degree(D)values of both were close to 1,the coordination level was also 10 for a long time,and the degree of coupling coordination was also maintained at the"high-quality coordination"level for a long time.[Conclusions]Forest has multiple benefits of society,economy and ecology,and forest carbon sink is only a benefit output.The long-term coupling analysis of forest carbon sink and forestry economic development is a key point to multiple benefit analysis.The analysis shows that the spillover effect and co-evolution effect of forest carbon sink in China are significant.From 1992 to 2018,the coupling coordination degree of forest carbon sink and forestry economic development was gradually rising.The prediction analysis also indicate that the coupling coordination degree between the forest carbon sink and the long-term development of forestry economy will remain at the level of"high-quality coordination"for a long time from 2019 to 2030.Therefore,improving the level of forest management and maintaining the current trend of increasing forest resources are the key to achieving the goal of carbon peaking and carbon neutrality in China. 展开更多
关键词 Forest resources carbon stock Forest carbon sink Coupling coordination degree Forestry economic development long-term trend
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The Association Between Corporate Governance Mechanisms and Stock Investment Risk: Empirical Evidence From Thailand
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作者 Panya Issarawornrawanich Aim-orn Jaikengkit 《Journal of Modern Accounting and Auditing》 2012年第9期1311-1325,共15页
This study examines the association between corporate governance mechanisms (i.e., internal corporate governance, ownership structure, and external corporate govemance) and stock investment risk (i.e., idiosyncrati... This study examines the association between corporate governance mechanisms (i.e., internal corporate governance, ownership structure, and external corporate govemance) and stock investment risk (i.e., idiosyncratic risk, systematic risk, and total risk of non-financial listed firms in Thailand in 2007). The multiple regression analysis is employed to test the hypotheses, and the results suggest that firms with higher market power have lower systematic risk. It implies that firms with higher market power can reduce the unavoidable risk when compared with firms that have lower market power. Firms with more media coverage will have higher systematic risk, which indicates that firms which publish more news will have higher unavoidable risk. This research may be the first to provide the evidence of the association between corporate govemance mechanisms and stock investment risk. Interestingly still, this study has utilized the data of Thailand, which is an emerging market economy with a capital market structure different from those of the developed market economies, and the results of this study are anticipated to be applicable to other similar studies in other emerging market economies. 展开更多
关键词 corporate governance stock investment risk media coverage product market competition
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Westinghouse Electric Corp.plans long-term investment in China
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《Electricity》 1998年第1期50-50,共1页
WestinghouseElectricCorp.planslong-terminvestmentinChinaUS-basedWestinghouseElectricCorphasalong-termcommitm... WestinghouseElectricCorp.planslong-terminvestmentinChinaUS-basedWestinghouseElectricCorphasalong-termcommitmenttowardsitsinve... 展开更多
关键词 investment long-term Corp.plans ELECTRIC China
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Turnover Based Illiquidity Measurement as Investment Strategy on Zagreb Stock Exchange
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作者 Jelena Vidovic 《American Journal of Operations Research》 2020年第1期1-12,共12页
This paper deals with illiquidity measurement of stocks on Croatian Stock market. Illiquidity measures used in this paper are daily ratio of absolute stock return to its dollar volume (ILLIQ) and RCT (Relative change ... This paper deals with illiquidity measurement of stocks on Croatian Stock market. Illiquidity measures used in this paper are daily ratio of absolute stock return to its dollar volume (ILLIQ) and RCT (Relative change in turnover). Aim of this paper is to show that illiquidity measure RCT makes clear distinction between liquid and illiquid stocks that should be reflected through investment strategy where investment in RCT based illiquid portfolios outperforms investment in ILLIQ based portfolios and CROBEX index. Research was carried out on eighteen stocks from Zagreb Stock Exchange (ZSE) which are constituents of CROBEX index. Portfolios of liquid and portfolios of illiquid stocks based on results of illiquidity measurement were constructed. Behaviour in terms of return and volatility of these portfolios in following one-year period was observed. Results showed that portfolios formed using RCT as measure of illiquidity constantly outperformed CROBEX index and ILLIQ based portfolios. Returns of RCT based portfolios had lower standard deviation and were more stable than ILLIQ based portfolios in whole period. RCT as a measure of illiquidity produces valuable information on stock liquidity that can be exploited as investment strategy reflecting itself in larger expected returns of RCT portfolios in future period than expected returns of ILLIQ based portfolios and market. 展开更多
关键词 Illiquidity Measure investment PORTFOLIO stock TURNOVER
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REGULATIONS ON THE ALTERATION OF STOCK EQUITY HELD BY INVESTORS OF FOREIGN INVESTMENT ENTERPRISES
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《大经贸》 北大核心 1997年第8期86-88,共3页
Article 1With a view to promoting the healthy development of foreign invest-ment enterprises, protecting the legitimate rights and interests of investorsof the parties concerned and safeguarding the social and economi... Article 1With a view to promoting the healthy development of foreign invest-ment enterprises, protecting the legitimate rights and interests of investorsof the parties concerned and safeguarding the social and economic order,this set of regulations has been formulated in accordance with the Com-pany Law of the People’s Republic of China,Law of the People’s Republicof China on Chinese-Foreign Equity Joint Ventures,Law of the People’sRepublic of China of Foreign on Chinese-Foreign contractual Joint Ven-tures,Law of the people’s of China of Foreign Capital Enterprises,andother relevant laws and regulations.Article 2The alteration of investors’stock equity in foreign investment enter-prises as used hereof refers to the alteration of investors or theirshares(hereinafter referred to as the stock equity) of financialcontribution(inchiding the cooperative conditions offered) in Chinese-for-eign equity joint ventures,Chinese-foreign contractual joint ventures andforeign investment enterprises(hereinafter referred to as the enterprises). 展开更多
关键词 REGULATIONS ON THE ALTERATION OF stock EQUITY HELD BY investORS OF FOREIGN investment ENTERPRISES
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Impacts of Land Cover Changes on Ecosystem Carbon Stocks Over the Transboundary Tumen River Basin in Northeast Asia 被引量:7
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作者 XIANG Hengxing JIA Mingming +5 位作者 WANG Zongming LI Lin MAO Dehua ZHANG Da CUI Guishan ZHU Weihong 《Chinese Geographical Science》 SCIE CSCD 2018年第6期973-985,共13页
Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and envi- ronmental protection, particularly in the transboundary region that has undergone marked chang... Understanding the effects of land cover changes on ecosystem carbon stocks is essential for ecosystem management and envi- ronmental protection, particularly in the transboundary region that has undergone marked changes. This study aimed to examine the impacts of land cover changes on ecosystem carbon stocks in the transboundary Tureen River Basin (TTRB). We extracted the spatial information from Landsat Thematic Imager (TM) and Operational Land Imager (OLI) images for the years 1990 and 2015 and obtained convincing estimates of terrestrial biomass and soil carbon stocks with the INVEST model. The results showed that forestland, cropland and built-up land increased by 57.5, 429.7 and 128.9 km2, respectively, while grassland, wetland and barren land declined by 24.9, 548.0 and 43.0 km2, respectively in the TTRB from 1990 to 2015. The total carbon stocks encompassing aboveground, belowground, soil and litter layer carbon storage pools have declined from 831.48 Tg C in 1990 to 831.42 Tg C in 2015 due to land cover changes. In detail, the carbon stocks de- creased by 3.13 Tg C and 0.44 Tg C in Democratic People's Republic of Korea (North Korea) and Russia, respectively, while increased by 3.51 Tg C in China. Furthermore, economic development, and national policy accounted for most land cover changes in the TTRB. Our results imply that effective wetland and forestland protection policies among China, North Korea, and Russia are much needed for protecting the natural resources, promoting local ecosystem services and regional sustainable development in the transnational area. 展开更多
关键词 land cover change carbon stock invest model Transboundary Tumen River Basin Northeast Asia
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耦合InVEST与FLUS模型的海南岛生态系统碳储量时空演变与预测 被引量:5
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作者 方赞山 钟才荣 +3 位作者 王凤霞 程成 吕晓波 陈旭 《水土保持通报》 CSCD 北大核心 2023年第5期320-329,342,共11页
[目的]通过研究海南岛城市化扩张下土地利用变化对碳储量的影响,揭示碳储量时空格局演变和预测未来发展趋势,为优化国土空间布局和生态敏感区的保护提供科学依据。[方法]基于1980—2020年土地利用数据,采用InVEST模型碳储量模块反演1980... [目的]通过研究海南岛城市化扩张下土地利用变化对碳储量的影响,揭示碳储量时空格局演变和预测未来发展趋势,为优化国土空间布局和生态敏感区的保护提供科学依据。[方法]基于1980—2020年土地利用数据,采用InVEST模型碳储量模块反演1980—2020年海南岛碳储量时空变化,并耦合FLUS模型和InVEST模型模拟自然发展情景、快速发展情景和生态保护情景3种发展情景下2030年海南岛的土地利用和碳储量变化情况。[结果](1)海南岛土地利用类型以林地、耕地为主。1980—2020年耕地、草地、林地和未利用地面积均有不同程度减少。建设用地和水域面积增加,尤以建设用地面积增长最快,增幅为83.4%。(2)海南岛碳储量总体呈“中间高,四周低”的特点,1980—2000年碳储量变化较小,降幅约0.03%。2000—2020年海南岛城镇化进程加快,碳储量损失也随之加剧,年均损失约372 t,累计损失碳储量7 439 t。(3)未来建设用地仍会继续扩张,受此影响3个情景下2030年海南岛碳储量均呈现降低的趋势。其中,快速发展情景下建设用地土地利用变化量最大,碳储量最易流失,自然发展情景次之,生态保护情景变化最小。[结论]在海南自由贸易港未来的土地利用规划中,应加强中部山区、自然保护地等重点生态区位的保护力度,优化土地利用格局,严格控制林地、耕地和湿地向建设用地转变,提高固碳增汇效能,实现区域可持续发展。 展开更多
关键词 碳储量 土地利用变化 invest模型 FLUS模型 海南岛
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Positive Study on the Risks of Investment
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作者 Zuo Xiaode Liang Yun Luo Lei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第4期37-42,共6页
In this paper, an empirical research on the system risks of the Shenzhen Stock Market using capital asset pricing model is conducted. The typical composition stocks on Shenzhen Stock Market in 1998 are taken as sample... In this paper, an empirical research on the system risks of the Shenzhen Stock Market using capital asset pricing model is conducted. The typical composition stocks on Shenzhen Stock Market in 1998 are taken as samples. Some quantitative analysis results are got, which can measure the risk of stock market. 展开更多
关键词 investment stock market Risk.8
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基于InVEST与MaxEnt模型的海南岛红树林生态系统碳储量增量预估 被引量:2
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作者 史娴 聂堂哲 +6 位作者 熊千 刘兆鑫 张嘉怡 刘文杰 乌兰 崔嵬 孙仲益 《热带生物学报》 2023年第3期298-306,共9页
为了解决在海南岛哪儿种红树、如何种红树能增汇的问题,基于生物气候、水文、地质及土地利用等数据,在最大熵(MaxEnt)模型评估所得的海南岛红树林生长适宜区基础上,预测红树林潜在扩种区域范围;结合潜在扩种范围和不同区域红树林生态系... 为了解决在海南岛哪儿种红树、如何种红树能增汇的问题,基于生物气候、水文、地质及土地利用等数据,在最大熵(MaxEnt)模型评估所得的海南岛红树林生长适宜区基础上,预测红树林潜在扩种区域范围;结合潜在扩种范围和不同区域红树林生态系统碳密度调查数据,利用InVEST模型对海南岛红树林生态系统碳储量增量进行预估。结果表明:(1)MaxEnt模型与InVEST模型结合能够良好地预估红树林碳储量,其中红树林潜在分布区的预测达到高信度(AUC>0.96);(2)海南岛红树林生态系统现状碳储量约为1.24 Tg,其中土壤碳约0.84 Tg,总碳密度为217.01 t·hm^(−2),土壤碳密度为147.43 t·hm^(−2)。以历史上海南岛最大的红树林分布面积12506 hm^(2)作为潜在扩种范围控制线,理论上海南岛红树林生态系统在扩种上限情景下能够为碳中和目标的实现贡献碳储量增量约1.25 Tg,而在扩种下限情景即仅保证完成《红树林保护修复专项行动计划(2020—2025)》扩种2000 hm^(2)红树林的基本任务情景下,可实现约0.38 Tg碳储量增量。 展开更多
关键词 MaxEnt模型 invest模型 碳储量增量 潜在分布 红树林生态系统 海南岛
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