期刊文献+
共找到1,561篇文章
< 1 2 79 >
每页显示 20 50 100
Activity Data and Emission Factor for Forestry and Other Land Use Change Subsector to Enhance Carbon Market Policy and Action in Malawi
1
作者 Edward Missanjo Henry Kadzuwa 《Journal of Environmental Protection》 2024年第4期401-414,共14页
Activity data and emission factors are critical for estimating greenhouse gas emissions and devising effective climate change mitigation strategies. This study developed the activity data and emission factor in the Fo... Activity data and emission factors are critical for estimating greenhouse gas emissions and devising effective climate change mitigation strategies. This study developed the activity data and emission factor in the Forestry and Other Land Use Change (FOLU) subsector in Malawi. The results indicate that “forestland to cropland,” and “wetland to cropland,” were the major land use changes from the year 2000 to the year 2022. The forestland steadily declined at a rate of 13,591 ha (0.5%) per annum. Similarly, grassland declined at the rate of 1651 ha (0.5%) per annum. On the other hand, cropland, wetland, and settlements steadily increased at the rate of 8228 ha (0.14%);5257 ha (0.17%);and 1941 ha (8.1%) per annum, respectively. Furthermore, the results indicate that the “grassland to forestland” changes were higher than the “forestland to grassland” changes, suggesting that forest regrowth was occurring. On the emission factor, the results interestingly indicate that there was a significant increase in carbon sequestration in the FOLU subsector from the year 2011 to 2022. Carbon sequestration increased annually by 13.66 ± 0.17 tCO<sub>2</sub> e/ha/yr (4.6%), with an uncertainty of 2.44%. Therefore, it can be concluded that there is potential for a Carbon market in Malawi. 展开更多
关键词 activity Data Emission Factor Climate change Forestland Carbon market
下载PDF
改革年代下民营经济的扩张与市场的生成——评Capitalism from Below:Markets and Institutional Change in China 被引量:1
2
作者 游宇 《公共管理评论》 CSSCI 2018年第1期126-135,共10页
中国的经济改革与市场从何而来?思考这一问题无疑可以帮助我们更好地厘清改革开放以来中国经济高速发展的潜在机制。倪志伟与欧索菲的研究观点明确:自上而下的'国家中心论'对这一问题的解释力度十分有限,而经济制度的内生性演... 中国的经济改革与市场从何而来?思考这一问题无疑可以帮助我们更好地厘清改革开放以来中国经济高速发展的潜在机制。倪志伟与欧索菲的研究观点明确:自上而下的'国家中心论'对这一问题的解释力度十分有限,而经济制度的内生性演化以及内嵌于制度之中的社会规范与社会网络机制才是解题的关键。利用详实的问卷分析与深入访谈,作者发现,社会互动和社会规范在民营企业发展与市场形成的多个层面起到了重要作用,包括企业创立、信贷融资、招工用工、组织变革、产业集群以及技术创新等。同时,面对政治资本这一竞争性解释,作者的分析也表明,拥有政治关联与支持的企业并非拥有竞争优势。该研究的理论框架、实证分析以及所拓展的思想领域,无疑会使其成为相关领域的重要参考。当然,该研究并非没有值得商榷之处。在最后一部分,本文对该研究的分析思路、与现实和现有发现的冲突以及解释边界等问题进行了讨论。 展开更多
关键词 民营企业 制度变革 市场生成
下载PDF
Design of a Social Marketing Plan on Salt Reduction for the Control and Treatment of Noncommunicable Diseases in Costa Rica
3
作者 Adriana Blanco-Metzler Hilda Patricia Nuñez-Rivas +3 位作者 Marlene Roselló-Araya Karol Madriz-Morales Karla Benavides-Aguilar Marco Castro-Araya 《Food and Nutrition Sciences》 2023年第11期1057-1077,共21页
High blood pressure and other non-communicable diseases associated with excessive salt/sodium consumption represent a major challenge to the health of the world’s population. Consumption is a human behavior that is u... High blood pressure and other non-communicable diseases associated with excessive salt/sodium consumption represent a major challenge to the health of the world’s population. Consumption is a human behavior that is usually influenced by significant factors, internal and external to people. The design of a national social marketing intervention is described. The whole process was developed by a national interdisciplinary team over the course of a decade (2011-2022). Its purpose is to promote changes in this behavior, through gradual reduction of salt/sodium consumption in the target populations of Costa Rica, for the prevention and control of associated diseases. The process includes four phases: research, situation analysis, creation of a proposal for the social marketing strategy, and implementation and evaluation. Last phase was not developed by the research team. The main inputs used to design this intervention were the data generated in three qualitative researchers carried out by the national work team and the social marketing regional plan for salt consumption reduction in Latin America. By analyzing these research data, marketing mix components were determined for designing the intervention. The marketing strategy is promotional and is based on encouraging a natural diet with less sodium using natural seasonings and adding less discretional salt and industrialized products high in sodium, in the preparation of food and dishes. The primary key audience is the mother of the school-aged child, and the secondary is the adult caregivers of this child. It is expected that in the short term, health promoters from different government and non-state sectors will contribute to the implementation of the national social marketing plan, to achieve, in the medium or long term, a consumption that approaches five grams of salt per person per day. This plan is a country initiative to position the value of a natural diet with less sodium and to contribute to the prevention and treatment of HT and NCD associated diseases. 展开更多
关键词 SaLT Social marketing Behavior change Noncommunicable Diseases SODIUM
下载PDF
我国碳市场与化石能源市场溢出效应研究——基于VAR-GARCH-BEKK模型的分析
4
作者 赵一航 赵会茹 《工业技术经济》 北大核心 2024年第4期36-45,共10页
碳市场的建立是实现“双碳”目标的重要保障,分析碳市场与化石能源市场间的溢出效应有助于提升市场流动性、规避碳金融风险,从而更好地推动国家气候战略目标。本文运用主成分分析方法将我国8个碳试点价格集成,明确试点阶段我国碳市场的... 碳市场的建立是实现“双碳”目标的重要保障,分析碳市场与化石能源市场间的溢出效应有助于提升市场流动性、规避碳金融风险,从而更好地推动国家气候战略目标。本文运用主成分分析方法将我国8个碳试点价格集成,明确试点阶段我国碳市场的整体发展规律,并通过VAR-GARCH-BEKK模型,进一步探究了全国统一碳市场建立前后碳市场与化石能源市场之间溢出效应的变化情况。结果表明,试点阶段碳市场与各类化石能源市场之间均存在显著的单向均值溢出效应。然而,在全国碳排放权交易市场建立初期,仅有部分发电行业参与交易,这在一定程度上削弱了碳市场与化石能源市场之间的联动关系,造成了二者之间均值溢出效应的下降。此外,全国统一碳市场的建立吸引了更多的投资者,加剧了碳市场和化石能源市场间的风险传染,需要进一步完善监管政策体系,保障碳市场平稳健康运行。 展开更多
关键词 碳市场 化石能源市场 溢出效应 VaR-GaRCH-BEKK模型 碳试点 主成分分析法
下载PDF
Livelihood Vulnerability and Adaptation for Households Engaged in Forestry in Ecological Restoration Areas of the Chinese Loess Plateau
5
作者 YANG Qingqing CHEN Yang +2 位作者 LI Xiaomin YANG Jie GAO Yanhui 《Chinese Geographical Science》 SCIE CSCD 2024年第5期849-868,共20页
Chinese Loess Plateau has achieved a win-win situation concerning ecological restoration and socio-economic development.However,synergistic development may not be realized at the local scale.In areas undergoing ecolog... Chinese Loess Plateau has achieved a win-win situation concerning ecological restoration and socio-economic development.However,synergistic development may not be realized at the local scale.In areas undergoing ecological restoration,livelihood vulner-ability may be more pronounced due to the inflexibility,policy protection,and susceptibility to climate and market changes in forestry production.Although this issue has attracted academic interest,empirical studies are relatively scarce.This study,centered on Jiaxian County,Shaanxi Province of China explored the households’livelihood vulnerability and coping strategies and group heterogeneity con-cerned with livelihood structures or forestry resources through field investigation,comprehensive index assessment,and nonparametric tests.Findings showed that:1)the percentage of households with high livelihood vulnerability indicator(LVI)(>0.491)reached 46.34%.2)Eight groups in livelihood structures formed by forestry,traditional agriculture,and non-farm activities were significantly different in LVI,land resources(LR),social networks(SN),livelihood strategies(LS),housing characteristics(HC),and socio-demo-graphic profile(SDP).3)The livelihood vulnerability of the groups with highly engaged/reliance on jujube(Ziziphus jujuba)forest demonstrated more prominent livelihood vulnerability due to the increased precipitation and cold market,where the low-engaged with reliance type were significantly more vulnerable in LVI,SDP,LR,and HC.4)The threshold of behavioral triggers widely varied,and farmers dependent on forestry livelihoods showed negative coping behavior.Specifically,the cutting behavior was strongly associated with lagged years and government subsidies,guidance,and high returns of crops.Finally,the findings can provide guidance on the dir-ection of livelihood vulnerability mitigation and adaptive government management in ecologically restored areas.The issue of farmers’livelihood sustainability in the context of ecological conservation calls for immediate attention,and eco-compensations or other forms of assistance in ecologically functional areas are expected to be enhanced and diversified. 展开更多
关键词 livelihood vulnerability FORESTRY coping behaviors climate change market change Jiaxian County
下载PDF
Reforms in the Education System Follow up the Change in the Role of the School Principal, and Its Impact on the Implementation of the Change of Education
6
作者 Saab Horriyah Manal SPANIOLI West University of Timisoara +1 位作者 Timisoara Romania 《Chinese Business Review》 2017年第7期337-349,共13页
In the recent decades, the academic literature engages more and more with reforms in the education system. These reforms that are worldwide seek to create change in education (Adler, 2010). If it's regarding the po... In the recent decades, the academic literature engages more and more with reforms in the education system. These reforms that are worldwide seek to create change in education (Adler, 2010). If it's regarding the position of the school principal as designer leader has significant role in the reforms management, but, moreover the role of this article is to the change of the role of the school principal over the years. The functions of the school principal integrate managerial aspects and leadership aspects and its importance is immenseness of the operation of the school organization, both in the terms of the organization customers, the pupils, and in the terms of the organization's staff--teachers. Not less important is the operation and implementation of educational reforms. We have to see the role of the school principal as the most significant to the implementing of the reform in the education system. 展开更多
关键词 REFORMS change management school principal
下载PDF
Change of Customer Concept in Marketing Activities
7
作者 Xun LI 《International English Education Research》 2014年第3期121-122,共2页
Marketing concept refers to the guiding ideology of correctly dealing with the interest relationship among enterprise, customers and society and also the fundamental standard for behaviors in the process of an enterpr... Marketing concept refers to the guiding ideology of correctly dealing with the interest relationship among enterprise, customers and society and also the fundamental standard for behaviors in the process of an enterprise to carry out all marketing activities in a certain period of time, production and business technology, and market environmental conditions. In this paper, the change of customer concept in marketing activities is mainly discussed. Therefore, this paper is of certain practical and guiding significance. 展开更多
关键词 marketing activities CUSTOMERS Definitions change of Concept
下载PDF
Labor Market Changes during Transformation and Upgrading of China's Three Major Special Economic Zones 被引量:1
8
作者 Lili HAN 《Asian Agricultural Research》 2018年第10期1-6,共6页
Regional economic integration can enhance the overall strength and competitiveness of the zone. The Yangtze River Delta,the Pearl River Delta and the Beijing-Tianjin-Hebei economic circles are the top three zones with... Regional economic integration can enhance the overall strength and competitiveness of the zone. The Yangtze River Delta,the Pearl River Delta and the Beijing-Tianjin-Hebei economic circles are the top three zones with economic viability in China. With the development of the economy,these three zones all follow the modern " tertiary,secondary,primary" industrial structure,while the corresponding employment population structure lags behind to a certain extent. Besides,the three major special economic zones are the regions receiving most of the migrant population in China. The inflow of labor has played a double-edged role in local economic and social development. Through systematically comparing the labor market changes in transformation and upgrading of the three major special economic zones,the reform experience could be obtained: urbanization can promote urban employment,industrial agglomeration can attract different employment types,and labor market system reform can enhance labor coordination in the zone. 展开更多
关键词 区域经济一体化 产业结构 发展现状 农业
下载PDF
基于K-means和主成分分析的京张体育文化旅游带冰雪运动旅游市场研究
9
作者 王光军 王姣姣 +2 位作者 赵小勇 商万军 杨义风 《河北北方学院学报(社会科学版)》 2024年第2期16-19,88,共5页
使用问卷调查、K-means聚类分析和主成分因子分析等方法对后冬奥时期京张体育文化旅游带的冰雪运动旅游市场进行分析发现,该市场可细分为青年冰雪爱好者、家庭亲子游客、中老年休闲游客和高端商务游客等类别。其中:青年和家庭市场为主力... 使用问卷调查、K-means聚类分析和主成分因子分析等方法对后冬奥时期京张体育文化旅游带的冰雪运动旅游市场进行分析发现,该市场可细分为青年冰雪爱好者、家庭亲子游客、中老年休闲游客和高端商务游客等类别。其中:青年和家庭市场为主力,市场需求集中在专业冰雪设施服务和冰雪文化体验等方面。据此,提出提升冰雪运动品质安全、丰富文化内涵和满足个性化需求等策略,以挖掘市场潜力,促进该地区冰雪旅游经济的可持续发展。 展开更多
关键词 冰雪运动旅游 市场细分 市场定位 K-means聚类分析 主成分因子分析
下载PDF
Structural Changes in the Chinese Stock Market: A Review of Empirical Research 被引量:1
10
作者 Haitian Lu Jiajia Fu 《中国会计与财务研究》 2014年第2期39-65,共27页
关键词 中国股票市场 结构 综述 中国环境 发达国家 股票发行 民营企业 上市公司
下载PDF
Physiological Changes during the Process of Pericarp Browning in the Postharvest Litchi 被引量:9
11
作者 王家保 王向社 +1 位作者 徐碧玉 金志强 《Agricultural Science & Technology》 CAS 2010年第5期10-16,共7页
[Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determ... [Objective] Pericarp browning in the postharvest litchi significantly reduced its commercial value and limited the expanding of litchi markets. Physiological changes during the process of pericarp browning were determined in order to identify the underlying mechanisms. [Method] Matured Feizixiao fruits were stored at 25 ℃ and 70%±5% relative humidity. The physiological changes happened in pericarp during storage were tested at an 8-hour interval. [Result] The fruit of Feizixiao (Litchi chinensis Sonn. cv Feizixiao) turned completely brown within 72 h after being harvested under the experimental conditions. Sharp increase of the browning index occurred from 48 to 64 hours after harvest (HAH). With the browning of pericarp,water content of the whole fruit and pericarp decreased continuingly. In contrast,there were no significant changes in the water content of pulp during the same period. MDA content,pH value and relative leakage rate of pericarp were increased during storage. Most of pigment contents including anthocyanin,flavonoid,phenols,chlorophyll a and total chlorophyll decreased. POD activity was initially increased in 32 HAH and then decreased afterwards. PPO activity was decreased continuously,while the activities of catalase and superoxide dismutase exhibited the pattern of 'increasing-decreasing-increasing' as the storage time progressed. Correlation,stepwise regression and path analyses showed that water loss of pericarp was the major factor of pericarp browning. Principal and cluster analyses showed that there were two stages of pericarp browning during the course of litchi storage. [Conclusion] Water status of pericarp was the most important factor affecting pericarp browning. The pericarp browning happened by stages,which was mainly determined by the water loss of pericarp. 展开更多
关键词 Litchi (Litchi chinensis Sonn.) Pericarp browning Physiological changes principal analysis:Cluster analysis
下载PDF
Landscape Changes from 1974 to 1995 in the Upper Minjiang River Basin, China 被引量:16
12
作者 HE Xing-Yuan ZHAO Yong-Hua +2 位作者 HU Yuan-Man CHANG Yu ZHOU Qi-Xing 《Pedosphere》 SCIE CAS CSCD 2006年第3期398-405,共8页
Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for... Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for local decision-making as well as sustainable landscape use and management. Results revealed that landscape from 1974 to 1995 changed at the regional scale as the area of forestland decreased, while cropland, shrubland, economic forest, grassland, and built-up land increased. Landscape changes mainly occurred in forestland, shrubland, grassland, economic forest, and built-up land. Moreover, the changes among forestland, shrubland, and grassland were the largest, influencing the whole characteristics of the changes in the basin. Analysis of the changes between 1974 and 1995 in the study area indicated that landscape heterogeneity and fragmentation increased, whereas landscape connectivity decreased. There were multiple reasons for landscape changes. A principal component analysis (PCA) was used to quantitatively study driving forces of landscape changes. The PCA results showed that economic and population factors were the principal driving forces of landscape changes from 1974 to 1995 in the upper Minjiang River basin, and that PCA was a suitable method for investigating driving forces of landscape changes. 展开更多
关键词 driving forces landscape change satellite image quantification principal component analysis
下载PDF
On arable land changes in Shandong Province and their driving forces 被引量:5
13
作者 SHAO Xiao-mei, ZHANG Hong-ye (Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第3期329-335,共7页
The decrease of total cultivated area and the lower per capita available arable land resource are now serious problems in Shandong Province, a major agricultural province in China. These problems will become more seri... The decrease of total cultivated area and the lower per capita available arable land resource are now serious problems in Shandong Province, a major agricultural province in China. These problems will become more serious along with the further development of economy. In this paper, based on the statistical information at provincial and county levels, the changes of arable land in Shandong Province and their driving forces during the last 50 years are analyzed. The general changing trends of arable land and per capita available arable land are reducing, and the trends of decrease will continue when the economy is developing. The result of GIS spatial analysis shows that the change of the arable land use in Shandong Province has a regional difference. Eight variables having influences on cultivated land change are analyzed by principal component analysis. The results show that the dynamic development of economy, pressure of social system and progress of scientific techniques in agriculture are the main causes for cultivated land reduction. The principal factors which can be considered as driving forces for arable land change include per capita net living space, total population and per ha grain yield. By using regressive equation, along with analysis on population growth and economic development, cultivated areas in Shandong Province in 2005 and 2010 are predicted respectively. The predicted cultivated areas in Shandong will be 6435.47 thousand hain 2005 and 6336.23 thousand ha in 2010 respectively. 展开更多
关键词 arable land dynamic change driving forces principal component analysis Shandong Province
下载PDF
Analysis of vulnerability and resilience to climate change induced shocks in North Shewa, Ethiopia 被引量:5
14
作者 Gutu Tesso Bezabih Emana Mengistu Ketema 《Agricultural Sciences》 2012年第6期871-888,共18页
This article analyzes the vulnerability and resilience levels of farm households in North Shewa, Ethiopia, using a survey of 452 households. Agro ecological based classification was done to analyze vulnerability to cl... This article analyzes the vulnerability and resilience levels of farm households in North Shewa, Ethiopia, using a survey of 452 households. Agro ecological based classification was done to analyze vulnerability to climate change induced shocks. Integrated vulnerability analysis approach was employed to develop indexes for socioeconomic and biophysical indicators. The indicators have been classified into adaptive capacity, exposure and sensitivity to climate change impact. Then Principal Component Analysis was used to compute vulnerability index of each agro ecological zone. The result shows that farmers living in the highland areas were very much vulnerable to natural shocks compared to those living in the lowland area. In order to identify and analyse the determinants of resilience to climate change impacts, ordered probit model was used. Households were classified into three categories based on the time they take to bounce back after natural shocks. The model outputs indicate that farmers with better investment on natural resource management, access to market, better social network, access to credit, preparedness, saving liquid assets, access to irrigation and better level of education exhibited greater level of resilience during and after climate change induced shocks. 展开更多
关键词 Climate change VULNERaBILITY RESILIENCE principal Component aNaLYSIS ORDERED PROBIT Ethiopia
下载PDF
Analysis to driving forces of land use change in Lu’an mining area 被引量:2
15
作者 LIU Chang-hua, MA Xiao-xiao School of Surveying and Land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期727-732,共6页
By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining ... By selecting impact factors of driving force and formulating evaluation criteria of the impacts, the evaluation system of corresponding driving force impact of land use change was established. Taking Lu'an mining area as an example, the specific impact factors of coal mine were comprehensively evaluated and analyzed in order to carry out qualitative and quantitative analysis for the driving force of mining-land use change. The principal component analysis shows that the social and economic development in mining area from 2000 to 2007 demonstrates continuous accelerate trends, and the impacts of its overall driving force to land use change are increased gradually. The socio-economic factors have more impacts to mining-land use change than those of the natural resources. The main driving force of mining-land use change also include population, technological progress and policy. 展开更多
关键词 MINING area LaND use change driving force evaluation FaCTOR principal component aNaLYSIS
下载PDF
Urban Land Use Change Detection Using Multisensor Satellite Images 被引量:5
16
作者 DENG Jin-Song WANG Ke +1 位作者 LI Jun DENG Yan-Hua 《Pedosphere》 SCIE CAS CSCD 2009年第1期96-103,共8页
Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in develope... Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in developed urban area in the coastal regions; therefore, there is an urgent need to effectively detect and monitor the land use changes and provide accurate and timely information for planning and management. In this study a method combining principal component analysis (PCA) of multisensor satellite images from SPOT (systeme pour l'observation de la terre or earth observation satellite)-5 multispectral (XS) and Landsat-7 enhanced thematic mapper (ETM) panchromatic (PAN) data, and supervised classification was used to detect and analyze the dynamics of land use changes in the city proper of Hangzhou. The overall accuracy of the land use change detection was 90.67% and Kappa index was 0.89. The results indicated that there was a considerable land use change (10.03% of the total area) in the study area from 2001 to 2003, with three major types of land use conversions: from cropland into built-up land, construction site, and water area (fish pond). Changes from orchard land into built-up land were also detected. The method described in this study is feasible and useful for detecting rapid land use change in the urban area. 展开更多
关键词 change detection land use multisensor satellite image principal component analysis (PCa urban area
下载PDF
International carbon markets under the Paris Agreement:Basic form and development prospects 被引量:1
17
作者 GAO Shuai LI Meng-Yu +1 位作者 DUAN Mao-Sheng WANG Can 《Advances in Climate Change Research》 SCIE CSCD 2019年第1期21-29,共9页
Article 6 of the Paris Agreement introduces two international carbon markets that receive extensive attention and are expected to play an important role in the post-2020 climate regime.Three key elements of the two in... Article 6 of the Paris Agreement introduces two international carbon markets that receive extensive attention and are expected to play an important role in the post-2020 climate regime.Three key elements of the two international carbon markets,including the scope,the types of tradable units and the governance,are identified,as the basis to clarify their basic forms.Based on the key issues and their different designs identified in negotiations,this study analyzes the contributions and challenges for China to participate in international carbon markets.Considering the inherent needs of climate change mitigation,climate finance,the development of a green"Belt and Road"and the China South-South cooperation in climate change,along with the existing domestic capacities on market mechanisms,this study puts forward the short-,medium-and long-term development prospects of the two international carbon markets. 展开更多
关键词 PaRIS aGREEMENT International carbon marketS COOPERaTIVE approaches SUSTaINaBLE development mechanism CLIMaTE change
下载PDF
Markov-Switching Time-Varying Copula Modeling of Dependence Structure between Oil and GCC Stock Markets 被引量:1
18
作者 Heni Boubaker Nadia Sghaier 《Open Journal of Statistics》 2016年第4期565-589,共25页
This paper proposes a Markov-switching copula model to examine the presence of regime change in the time-varying dependence structure between oil price changes and stock market returns in six GCC countries. The margin... This paper proposes a Markov-switching copula model to examine the presence of regime change in the time-varying dependence structure between oil price changes and stock market returns in six GCC countries. The marginal distributions are assumed to follow a long-memory model while the copula parameters are supposed to evolve according to the Markov-switching process. Furthermore, we estimate the Value-at-Risk (VaR) based on the proposed approach. The empirical results provide evidence of three regime changes, representing precrisis, financial crisis and post-crisis, in the dependence structure between energy and GCC stock markets. In particular, in the pre- and post-crisis regimes, there is no dependence, while in the crisis regime, there is significant tail dependence. For OPEC countries, we find lower tail dependence whereas in non-OPEC countries, we see upper tail dependence. VaR experiments show that the Markov-switching time- varying copula model performs better than the time-varying copula model. 展开更多
关键词 Time-Varying Copulas Markov-Switching Model Oil Price changes GCC Stock markets VaR
下载PDF
考虑流量局部变化与转移的移动App价格促销广告策略研究 被引量:1
19
作者 何向 李莉 +2 位作者 张华 朱星圳 杨文胜 《运筹与管理》 CSCD 北大核心 2023年第7期219-224,232,共7页
随着移动App市场中消费者流量的不断增加,越来越多的广告主选择在移动App市场中投放价格促销广告。本文分析了当移动App市场中的流量分别发生局部变化或相互转移时,广告主应如何制定其最优促销广告定价与最优广告投放水平。我们首先假... 随着移动App市场中消费者流量的不断增加,越来越多的广告主选择在移动App市场中投放价格促销广告。本文分析了当移动App市场中的流量分别发生局部变化或相互转移时,广告主应如何制定其最优促销广告定价与最优广告投放水平。我们首先假设市场不完全覆盖的情境,结果表明:(1)在广告主的局部市场与竞争市场中的流量发生局部变化下,广告主的产品定价与广告投放水平和竞争市场大小、竞争市场流量大小以及局部市场流量大小有关;(2)当流量在局部市场与竞争市场之间相互转移时,广告主还需考虑原市场中流量的大小来调整其价格促销广告策略;(3)当局部市场的流量大小不相等时,本文也为处于流量优势或劣势的广告主提供了相应的最优产品定价与广告投放水平策略的指导。本研究为移动App环境下网络营销企业广告策略的制定提供了理论参考。 展开更多
关键词 移动app市场 价格促销广告策略 流量局部变化 流量转移
下载PDF
Assessment of achievements of the Lima Climate Change Conference and perspectives on the future 被引量:1
20
作者 L Xue-Du 《Advances in Climate Change Research》 SCIE 2014年第4期219-223,共5页
The Lima call for climate action adopted at the Lima Climate Conference on Climate Change specifies that the principles of the United Nations Framework Convention on Climate Change,including the principle of common bu... The Lima call for climate action adopted at the Lima Climate Conference on Climate Change specifies that the principles of the United Nations Framework Convention on Climate Change,including the principle of common but differentiated responsibilities,shall apply to the new climate agreement to be adopted at the Paris Conference on Climate Change in 2015.Decisions on other heavily debated items,including the intended nationally determined contributions,were also made at the Lima Conference.The significant achievements in Lima and the positive momentum have laid a solid foundation for the adoption of a new climate agreement in the Paris Climate Conference.Four measures are proposed for China to meet great challenges in addressing climate change beyond 2020,including early formulation and issuance of a climate change law,establishment of a greenhouse gas emission trading scheme,promotion of advanced climate technology investments,and further international engagement for climate change. 展开更多
关键词 Lima Climate change Conference ad Hoc Working Group on the Durban Platform for Enhanced action Greenhouse gas mitigation Climate changenegotiation Carbon market Common but differentiated responsibilities
下载PDF
上一页 1 2 79 下一页 到第
使用帮助 返回顶部