检索结果-南通市图书馆

Journal of Systems Science & Complexity 2023年第1期36卷 360-374页

作者： CHAI Jian WANG Yabo HU Yi ZHANG Xuejun ZHANG Xiaokong School of economics and management Xidian UniversityXi’an 710126China School of economics and management University of Chinese Academy of SciencesBeijing 100190China

Under the goal of carbon neutrality,it is critical for china to give full play to the role of green credit,and promote the coordinated development of energy-environment-economy(3E)system.Based on the data of china from 2000 to 2020,the authors build the environmental pollution index,energy transformation index and high-quality economic development index.By using Bayesian network model(BN),the authors investigate the coupling relationships and influence mechanisms of green credit and 3E system.The results show that the main cause of environmental pollution is the annual increase of carbon dioxide emissions.Green credit can reduce carbon emissions to a certain extent,and alleviate environmental pollution through energy structure,technological progress and per capita GDP.Clean energy utilization and per capita GDP growth also help to control environmental pollution.Green credit can stimulate technological progress and accelerate energy transformation together with technological progress.Clean energy utilization can facilitate the upgrading of industrial structure,industrial structure upgrading and green credit can restrict the level of opening up.Technological progress promotes per capita GDP growth.Per capita GDP growth can reduce energy intensity and improve urbanization and per capita energy consumption.

关键词： Bayesian network carbon neutrality coupling nexus energy-environment-economy green credit

FACTORS INFLUENCING FOOD-WASTE BEHAVIORS AT UNIVERSITY CANTEENS IN BEIJING,china:AN INVESTIGATION BASED ON THE THEORY OF PLANNED BEHAVIOR

在线全文

学校读者我要写书评

暂无评论

农业科学与工程前沿:英文版 2023年第1期10卷 83-94页

作者： Hao FAN Jingjing WANG Xiaotong LU Shenggen FAN academy of Global Food economics and Policy College of Economics and ManagementChina Agricultural UniversityBeijing 100083China

Food waste is a major social problem that contributes to the overutilization of natural resources,affecting economic progress and environmental protection.Food waste occurs throughout the whole process of the food supply chain,especially during the consumption stage.As a special group of consumers,the emerging adults at university may have unique food consumption patterns and their food waste behavior in university canteens deserves more attention.To understand the influential factors of the food-waste behavior of students in university canteens,a field survey was conducted at china Agricultural University canteen with 705 respondents.Based on the theory of planned behavior,this paper examines the influencing factors of student food-waste behavior from three dimensions:sociopsychological factors,individual characteristics and dining factors.The results indicate that the percentage of students who waste food is relatively low,at roughly 27%.Perceived behavior control,gender,monthly living expenses,BMI,mealtime,meal expectations and food portion were significantly correlated with student food-waste behavior,among which perceived behavior control had the most prominent correlation,followed by food portion.Behavioral intention,household location and palatability were not significantly correlated with student food-waste behavior.Therefore,it is necessary to promote publicity and education on reducing food waste on campus,reinforce the administration of the department of support service,and optimize the food portion in the canteen.

关键词： university students food waste behavior theory of planned behavior university canteen

TRANSFORMING CHINESE FOOD AND AGRICULTURE:A SYSTEMS PERSPECTIVE

在线全文

学校读者我要写书评

暂无评论

Frontiers of Agricultural Science and Engineering 2023年第1期10卷 4-15页

作者： Ting MENG Shenggen FAN academy of Global Food economics and Policy(AGFEP) College of Economics and ManagementChina Agricultural UniversityBeijing 100083China

After decades of development,china has made significant progress in ensuring national food security.However,the country currently faces multiple challenges,including the double burden of malnutrition,i.e.,micronutrient deficiencies and overweight/obesity,climate change,resource stress and environmental degradation,and an increasingly complex global market.This paper reviews past developments in food and agriculture,and offers initial insights into transforming the Chinese food system for achieving multiple national development goals using a systems approach.Strategies and solutions from china can also inform the design and implementation of food system transformation in other emerging economies.

关键词： food systems food security nutrition climate change

A GENERALIZATION OF GAUSS-KUZMIN-LE′VY THEOREM

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2018年第3期38卷 965-972页

作者：孙鹏 China Economics and Management Academy Central University of Finance and Economics

We prove a generalized Gauss-Kuzmin-L′evy theorem for the generalized Gauss transformation Tp（x） = {p/x}.In addition, we give an estimate for the constant that appears in the theorem.

关键词： Gauss transformation transfer operator Gauss’ problem Hurwitz zeta function

Impacts of CME Changing Mechanism for Allowing Negative Oil Prices on Prices and Trading Activities in the Crude Oil Futures Market

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2023年第5期36卷 2001-2025页

作者： LU Fengbin BU Hui academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of economics and management Beihang UniversityBeijing 100191China

This study investigates and compares the effects of the Coronavirus disease 2019(COVID-19)pandemic,the Chicago mercantile exchange(CME)'s negative price suggestion on prices and trading activities in the crude oil futures market to discuss the cause of negative crude oil futures prices.Through event studies,the empirical results show that the COVID-19 pandemic no longer impacts crude oil futures prices in April,2020 after controlled market risk,while the CME's negative prices suggestion can explain the crude oil futures price changes around and even after April 8,2020 to some degree.Moreover,this study uncovers anomalies in prices and trading activities by analyzing returns,trading volume,open interest,and illiquidity measures using vector autoregressive(VAR)models.The results imply that CME's allowing negative prices strengthens the price impact on trading volume and makes illiquidity risk matter.This study's results coincide with the following lawsuit evidence of market manipulation.

关键词： Event study illiquidity risk market risk negative crude oil futures price price-trading relationship

Government Investment and High-Quality Economic Development——Measurement and Analysis Based on Input-Output Method

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2022年第3期35卷 993-1008页

作者： YANG Xuelian TIAN Kailan ZHU Lingxiu YANG Cuihong School of economics and management University of Chinese Academy of SciencesBeijing 100190China academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China

Analysis of how government investment promotes economic development and employment is important for improving government’s decision-making and promoting high-quality economic development in western china.In this paper,the authors take Xinjiang as an example to conduct such an analysis.Firstly,based on the competitive input-output table of Xinjiang,the non-competitive input-output tables of 2007,2012 and 2015 are compiled in this paper.Secondly,the contribution of Xinjiang government investment,especially the major government investment projects,to the valueadded of Xinjiang,other provinces and cities in china and abroad are calculated.Thirdly,this paper uses the non-competitive input-output table to compile the sectoral employment vector,and uses the input-occupancy-output technique to measure how government investment promotes employment.The results show that Xinjiang government investment contributes the most to the value-added of Xinjiang and other provinces and cities,but less to foreign countries;the government investment create the most job opportunities in projects including transportation projects and livelihood projects etc.

关键词： Economic growth employment government investment high-quality economic development input-output model

Timing Prediction Error Volatility and Dynamic Asset Allocation

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2022年第1期31卷 111-130页

作者： Yun Shi academy of Statistics and Interdisciplinary Sciences Faculty of Economics and ManagementEast China Normal UniversityShanghai 200062China

We solve a portfolio selection,problem in which,return predictability,risk predictability and transaction cost are incorporated.In the problem,both expected return,prediction error volatility,and transaction cost are time-varying.Our optimal strategy suggests trading partially toward a dynamic aim portfolio,which is a weighted average of expected future tangency portfolio and is highly influenced by the common fluctuation of prediction error volatility(CPE).When CPE is high,the investor would invest less and trade less frequently to avoid risk and transaction cost.Moreover,the investor trades more closely to the aim portfolio with a more persistent CPE signal.We also conduct an empirical analysis based on the commodities futures in Chinese market.The results reveal that by timing prediction error volatility,our strategy outperforms alternative strategies.

关键词： Dynamic asset allocation prediction error volatility transaction cost return predictability volatility timing

Quantitative Analysis and Prediction of china's Natural Gas Consumption in Different Sectors Based on Bayesian Network

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science and Information 2022年第4期10卷 338-353页

作者： Jian CHAI Yabo WANG Zhaohao WEI Huiting SHI Xiaokong ZHANG Xuejun ZHANG School of economics and management Xidian UniversityXi’an 710126China School of economics and management University of Chinese Academy of SciencesBeijing 100190China

In view of the heterogeneity of natural gas consumption in different sectors in china,this paper utilizes Bayesian network(BN)to study the driving factors of natural gas consumption in power generation,chemical and industrial fuel sectors.Combined with Bayesian model averaging(BMA)and scenario analysis,the gas consumption of the three sectors is predicted.The results show that the expansion of urbanization will promote the gas consumption of power generation.The optimization of industrial structure and the increase of industrial gas consumption will enhance the gas consumption of chemical sector.The decrease of energy intensity and the increase of gas consumption for power generation will promote the gas consumption of industrial fuel.Moreover,the direct influencing factors of gas price are urbanization,energy structure and energy intensity.The direct influencing factors of environmental governance intensity are gas price,urbanization,industrial structure,energy intensity and energy structure.In 2025,under the high development scenario,china’s gas consumption for power generation,chemical and industrial fuel sectors will be 66.034,36.552 and 109.414 billion cubic meters respectively.From 2021 to 2025,the average annual growth rates of gas consumption of the three sectors will be 4.82%,2.18%and 4.43%respectively.

关键词： Bayesian network influence factors Bayesian model average forecast natural gas consumption in different sectors

Analysis of the Financing Mode of Small and Medium-Sized Enterprises Under the DC/EP Platform Based on a Comparison with the Traditional Bank Financing Mode

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Information 2023年第1期11卷 94-108页

作者： Yuting TU Huan WANG Xin YAN Yongwu LI School of economics and management University of Chinese Academy of SciencesBeijing 100190China School of economics and management Beijing University of TechnologyBeijing 100124China

As a legal currency with the credit endorsement of the Chinese government,DC/EP has many advantages and special characteristics.Based on the application of DC/EP in the financing of small-and medium-sized enterprises(SMEs),this paper studies the optimal financing decisions of SMEs under both the traditional financing mode and the DC/EP financing mode.Considering the construction and use costs of DC/EP and the role of DC/EP credit traceability in improving mortgage rates,this paper explores the feasible range for SMEs to select DC/EP financing.It is found that mortgage rates affect the returns of SMEs when they take on loans;under different credit strategies,the pledge rate set by the bank will affect the financing willingness of SMEs.The participants had different optimal mortgage rates to optimize the returns of borrowers and banks.High-quality SMEs are more willing to use the DC/EP platform for financing.With the increase in default costs,banks will be more inclined to use DC/EP,while enterprises will be inclined to utilize the traditional financing mode.Through the comparative analysis of the two financing modes,the default cost range that neither banks nor borrowers are willing to use DC/EP is found.This study provides theoretical support and management inspiration for scientific decision-making to solve the financing problems of SMEs by using DC/EP.

关键词： DC EP small and medium-sized enterprises financing mortgage rate

Narrative Graph:Telling Evolving Stories Based on Event-centric Temporal Knowledge Graph

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Systems Engineering 2023年第2期32卷 206-221页

作者： Zhihua Yan Xijin Tang academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China School of management Science and Engineering Shanxi University of Finance and EconomicsTaiyuan030006China University of Chinese academy of Sciences Beijing100039China

As the main channel for people to obtain information and express their opinions,online media generate a huge amount of unstructured news documents every day and make it difficult for people to perceive major societal events and grasp the evolution of events.Previous studies on storyline generation are generally based on document clustering without considering event arguments and relations between events.Event-centric knowledge graph has been used to facilitate the construction of news documents to form structured event representation.Although some studies have attempted to construct timelines based on event-centric knowledge graphs,it is difficult for timelines to depict the complex structures of event evolution.In this paper,we try to represent news documents as an event-centric knowledge graph,and compress the whole knowledge graph into salient complex events in temporal order to generate storylines named narrative graph.We first collect news documents from news platforms,construct an event ontology,and build an event-centric knowledge graph with temporal relations.Graph neural network is used to detect events,while BERT fine-tuning is leveraged to identify temporal relations between events.Then,a novel generation framework of narrative graph with constraints of coherence and coverage is proposed.In addition,a case study is implemented to demonstrate how to utilize narrative graph to analyze real-world event.The experiment results show that our approach significantly outperforms the baseline approaches.

关键词： Storyline event-centric knowledge graph event evolution community detection