期刊文献+
共找到11篇文章
< 1 >
每页显示 20 50 100
Impact and prediction of pollutant on mangrove and carbon stocks:A machine learning study based on urban remote sensing data 被引量:2
1
作者 Mengjie Xu Chuanwang Sun +1 位作者 Yanhong Zhan Ye Liu 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第3期401-418,共18页
Mangrove ecosystems have important ecological and economic values,especially their ability to store carbon.However,in recent years,human disturbance has accelerated mangrove degradation.Among them,the emission of poll... Mangrove ecosystems have important ecological and economic values,especially their ability to store carbon.However,in recent years,human disturbance has accelerated mangrove degradation.Among them,the emission of pollutants cannot be ignored.It is of great significance for carbon emission reduction and ecological protection to study the impacts of different pollutants on mangroves and their carbon stocks.Based on the remote sensing data of coastal areas south of the Yangtze River in China's Mainland,this paper builds the ensemble learning model Random Forest(RF)and Gradient Boosting Regression(GBR)to empirically analyse the relationship between industrial wastewater,industrial sulfur dioxide(SO2),PM2.5 and mangrove forests.The results show that the pollutant concentration of meteorological normalisation is more stable.The importance of pollutants presents regional heterogeneity.The area of mangroves in different cities and the corresponding total carbon stocks show different trends with the increase or decrease of pollutants,and there is a dynamic balance between urban pollutant discharge and mangrove growth in some cities.The research in this paper provides an analysis and explanation from the perspective of machine learning to explore the relationship between mangroves and pollutants and at the same time,provides scientific suggestions for the formulation of future pollutant emission policies in different cities. 展开更多
关键词 Mangrove forests POLLUTANTS Machine learning model Carbon stocks Regional heterogeneity
下载PDF
Evolution of China's Role in the Structure of Global Carbon Emission Transfers:An Empirical Analysis Based on Network Governance
2
作者 Bingbing Zhang Lelan Kong +1 位作者 Zhehong Xu Chuanwang Sun 《China & World Economy》 2024年第1期130-166,共37页
This paper reconsiders the roles of China and some developed countries in the network of carbon emission transfers via international trade in value added from a new perspective of network governance.Network search int... This paper reconsiders the roles of China and some developed countries in the network of carbon emission transfers via international trade in value added from a new perspective of network governance.Network search intensity(NSI)and the extended gravity model are used with cross-country panel data to analyze the mechanism of China's engagement in network governance of carbon emission transfers.The results show that from 2000 to 2009,China was a net exporter of carbon emissions,even though it shifted from the semi-periphery to the core in the network of carbon emissions embodied in imports.Meanwhile,NSI had a significant positive impact on carbon emissions embodied in exports.Given China's important role in the global production network and division of labor,NSI may also affect industrial structure and the quality of the ecological environment to a large extent.This study analyses the network governance mechanism of China's participation in global carbon transfers.The results suggest that the technical complexity of export products and product heterogeneity do not change the positive impact of NSI on carbon emissions. 展开更多
关键词 carbon emission transfers gravity model network governance network search intensity
原文传递
大学校园闲置物品网络交易平台需求与规划 被引量:2
3
作者 王智航 周扶摇 +2 位作者 郝禹涵 魏京京 周广艳 《河北北方学院学报(社会科学版)》 2020年第4期75-77,共3页
随着电商平台如雨后春笋般发展起来,校园闲置物品已经成为亟待解决的一大浪费问题。对不同大学进行了问卷形式的抽样调查,结果显示绝大部分学生拥有闲置物品,且对闲置物品进行处理的意愿较强。针对此调查结果所显示的需求,设计大学校园... 随着电商平台如雨后春笋般发展起来,校园闲置物品已经成为亟待解决的一大浪费问题。对不同大学进行了问卷形式的抽样调查,结果显示绝大部分学生拥有闲置物品,且对闲置物品进行处理的意愿较强。针对此调查结果所显示的需求,设计大学校园闲置物品网络交易平台。通过该网络平台能够解决当前大学生闲置物品无处安放的问题,实现闲置物品的再利用。 展开更多
关键词 高校学生 闲置物品 网络平台 交易
下载PDF
Static Model Classification Status: Taking Into Account Emerging External Factors
4
作者 Perminov G. I. 《Journal of Modern Accounting and Auditing》 2013年第6期798-807,共10页
Analysis of the problem of predicting bankruptcy shows that foreign and domestic models included only internal factors of enterprises. But the same indicators of internal factors in the rapidly changing external envir... Analysis of the problem of predicting bankruptcy shows that foreign and domestic models included only internal factors of enterprises. But the same indicators of internal factors in the rapidly changing external environment can lead to bankruptcy, and not in others. External factors are the most dangerous, because the possible influence on them is minimal and the impact of their implementation can be devastating. This paper focuses on the same factors to assess the impact of the macroeconomic indicators (extemal factors) on the parameters of static models predicting a local approximation of the crisis at the plant. To accomplish the purpose, a Spark set of 100 companies was compiled, including 50 companies which officially declared bankruptcy in the period of 2000-2009 and 50 stable operating companies with a random sample of the same time period. External factors were extracted from the Joint Economic and Social Data Archive1 The author compared two data sets: (1) microeconomic indicators--money to the total liabilities, retained earnings to total assets, net profit to revenue, Earnings Before Interest and Taxes (EBIT) to assets, net income to equity, net profit to total liabilities, current liabilities to total assets, the totality of short-term and long-term loans to total assets, current assets to current liabilities, assets to revenue, equity to total assets, and current assets to revenue; and (2) external factors--index of real gross domestic product (GDP), industrial production index, the index of real cash incomes, an index of real investments, consumer price index, the refinancing rate, unemployment rate, the price of electricity, gas prices, oil price, gas price, dollar to ruble, ruble euro Standard & Poor (S&P) index, the Russian Trading System (RTS) index, and region. The aim of the comparison results paging classes "insolvent" and "non-bankrupt" is achieved using two methods: classification and discrimination. In both methods, computational procedures are realized with the use of algorithms linear regression, artificial neural network, and genetic algorithm. In the 2-m model, data set includes both internal and external factors. The results showed that the inclusion of only the microeconomic indicators, excluding external factors, impedes models about two times. 展开更多
关键词 bankruptcy prediction external factors methods of classification and discrimination
下载PDF
西欧的风险意识
5
作者 Lennart Sjberg 王燕 《AMBIO-人类环境杂志》 1999年第6期545-551,576+509,共7页
本文描述了风险意识的经验性工作及其有关方面,尤其对辐射和核武器危险进行了较多的描述。所用数据多数来自目前西欧5国参与的CEC项目。对风险意识模型进行了讨论,并对一些和风险意识有关的普遍正确的结果进行了概括。在很多政治事务中... 本文描述了风险意识的经验性工作及其有关方面,尤其对辐射和核武器危险进行了较多的描述。所用数据多数来自目前西欧5国参与的CEC项目。对风险意识模型进行了讨论,并对一些和风险意识有关的普遍正确的结果进行了概括。在很多政治事务中风险被看作是一种主要因素,显而易见,对于大众来说,风险比实用性还重要。我们发现,以前构建的模型(心理测试模型和文化理论)存在一些不足之处,为此提出了一项更为有效的改进方法。本文强调,风险意识很有意思,其最主要的原因是,它对决策者在对具风险性事务作出有难度的政治决定上具有很高的价值。因此,重要的是要弄清所认识到的风险在哪些方面与减轻风险的要求最为密切相关。我们发现,预测某种风险结果的严重性是最重要的。本文以瑞典选择高水平核废料储藏地点的经历为例,通过简洁的概括,得出一些结论。 展开更多
关键词 风险意识 西欧地区 辐射 武器 环境评价
下载PDF
Solution to the Dilemma of the Migrant Labor Shortage and the Rural Labor Surplus in China 被引量:11
6
作者 Guifu Chen Shigeyuki Hamori 《China & World Economy》 SCIE 2009年第4期53-71,共19页
Since 2003, China's labor market has been facing two coexisting crises: a rural labor surplus and a severe shortage of migrant labor Using data from the 2000 China Health and Nutrition Survey questionnaire, which co... Since 2003, China's labor market has been facing two coexisting crises: a rural labor surplus and a severe shortage of migrant labor Using data from the 2000 China Health and Nutrition Survey questionnaire, which covers 288 villages in 36 counties, this paper attempts to find a solution to this dilemma. Specifically, a multinomial logit model, a Mincer- type model and a probit model are applied to examine the effect of educational level on the employment choices for rural laborers, and on the wages and the employment status of migrants. Based on the results of our analysis, we propose the implementation of policy aimed at increasing the educational level of rural dwellers, in conjunction with other policies to eliminate all artificial barriers, to facilitate the migration of rural laborers. 展开更多
关键词 Chinese labor market labor migration migrant labor shortage rural surplus labor force
原文传递
The term structure of Sharpe ratios and arbitragefree asset pricing in continuous time
7
作者 Patrick Beißner Emanuela Rosazza Gianin 《Probability, Uncertainty and Quantitative Risk》 2021年第1期23-52,共30页
Motivated by financial and empirical arguments and in order to introduce a more flexible methodology of pricing,we provide a new approach to asset pricing based on Backward Volterra equations.The approach relies on an... Motivated by financial and empirical arguments and in order to introduce a more flexible methodology of pricing,we provide a new approach to asset pricing based on Backward Volterra equations.The approach relies on an arbitrage-free and incomplete market setting in continuous time by choosing non-unique pricing measures depending either on the time of evaluation or on the maturity of payoffs.We show that in the latter case the dynamics can be captured by a time-delayed backward stochastic Volterra integral equation here introduced which,to the best of our knowledge,has not yet been studied.We then prove an existence and uniqueness result for time-delayed backward stochastic Volterra integral equations.Finally,we present a Lucas-type consumption-based asset pricing model that justifies the emergence of stochastic discount factors matching the term structure of Sharpe ratios. 展开更多
关键词 Volterra equations BSDES Asset pricing Time inconsistency Arbitrage-free Incomplete markets Term structures Sharpe ratio
原文传递
The Cosine-Shaped Pattern of Innovations and Technological Advantages: Theory and Evidence
8
作者 Jiandong Ju Xuebing Yang 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2013年第4期476-489,共14页
Using data from 24 OECD countries, we find that the relationship between a country's R&D investment and technological advantage in a sector (measured by the country's labor productivity of the sector relative to t... Using data from 24 OECD countries, we find that the relationship between a country's R&D investment and technological advantage in a sector (measured by the country's labor productivity of the sector relative to the rest of the world) is non-monotonic. In particular, for countries whose technology levels are much lower or higher than the rest of the world in a sector, their sectoral R&D investment declines as their advantages in the sector improve; for counties with middle technology levels, the opposite is true. Extending the Eaton and Kortum framework, we develop a static model to theoretically analyze the relationship between R&D investment and technological advantages. We show that when the research efficiency in a sector is sufficiently elastic with respect to the sectoral technological advantage, a country's R&D investment increases with its technological advantage, and vice versa. 展开更多
关键词 R&D patterns TRADE technological advantage
原文传递
Human Capital Expansion and Global Value Chain Upgrading:Firm-level Evidence from China 被引量:5
9
作者 Lamei Wu Guifu Chen Shuijun Peng 《China & World Economy》 2021年第5期28-56,共29页
Firms actively participate in the production of the global value chain(GVC),which is an important driving force for economic development.Using a difference-in-difference method,our research shows that industries that ... Firms actively participate in the production of the global value chain(GVC),which is an important driving force for economic development.Using a difference-in-difference method,our research shows that industries that are relatively more human-capital intensive experienced a larger GVC position upgrading after 2003 than they had in prior years.Second,mechanism analysis shows that human capital expansion increases firms’GVC position not only through an imported intermediate input effect but also through an innovation effect.Third,this study shows that increases in the college-educated labor force have a heterogeneous effect on a firm's GVC position across firms’various characteristics.Human capital expansion has the largest positive effect on state-owned firms relative to foreign and domestic private firms.Human capital expansion has also significantly improved the GVC position of firms located in China's eastern and central regions.The findings of this study indicate that it helps upgrading the GVC position of Chinese firms. 展开更多
关键词 global value chain position human capital expansion imported intermediate input effect innovation effect
原文传递
Aging and Migration: Micro and Macro Evidence from China 被引量:4
10
作者 Orn B. Bodvarsson Jack W. Hou Kailing Shen 《Frontiers of Economics in China-Selected Publications from Chinese Universities》 2016年第4期548-580,共33页
Post-reform China has been experiencing two major demographic changes: an increasingly aging population and an extraordinary surge of rural-urban migrants. The question we ask is: are these two demographic changes r... Post-reform China has been experiencing two major demographic changes: an increasingly aging population and an extraordinary surge of rural-urban migrants. The question we ask is: are these two demographic changes related? If yes, then, how? The standard view in the migration literature is that the older the migrant, the lower the likelihood of migration. This paper proposes a simple theory of temporary migration for unskilled labor to fit the context of China Motivated by our model, we then use both cross-sectional micro data and panel macro data to examine the potential impacts of aging on migration. We find that shifts in China's age distribution have generated significant changes in the country's migration patterns: migration will shift to closer provinces (probably switching from interprovincial migration to intra-provincial migration) and will concentrate to a few destination provinces. 展开更多
关键词 internal migration age distribution REFORM
原文传递
A future triple entry accounting framework using blockchain technology 被引量:1
11
作者 Moinak Maiti Ivan Kotliarov Vitalii Lipatnikov 《Blockchain(Research and Applications)》 2021年第4期56-63,共8页
The study adopts a single case study approach to bring into conversation,ideas,and views of several scholars on triple entry accounting(TEA).The development of blockchain technology already drives the conscious move t... The study adopts a single case study approach to bring into conversation,ideas,and views of several scholars on triple entry accounting(TEA).The development of blockchain technology already drives the conscious move towards the TEA.The TEA is currently not being used in any significant way but is in a greater debate whether it is worth adopting such alternative accounting practices as the TEA.Shifting to the TEA system is challenging and at present,it is just a fascinating mental exercise.With these backdrops,the present study discusses the likelihood cases of future accounting practice namely:(Ⅰ)Sophisticated Accounting Software based on the double entry accounting(DEA);(Ⅱ)Combination of Blockchain and TEA;and(Ⅲ)Combination of disruptive technologies in addition to Blockchain and TEA.Finally,the study concludes with describing the basic architecture of a potential system of triple-entry accounting that could support the TEA system to deliver real-time insights into business operations.Lastly,the study plotted a hype cycle for accounting technologies to help global organizations identify the relevant accounting technologies and applications. 展开更多
关键词 Double entry accounting Triple entry accounting Application programming interface Edge computing Blockchain
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部