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State-Owned Capital Participation in Private Enterprises:A Perspective of Debt Financing
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作者 He Dexu Zeng Min Zhang Shuonan 《China Economist》 2024年第1期14-42,共29页
This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study ... This study takes debt financing as the entry point and explores the impact of state-owned capital participation in private enterprises from the perspectives of“unarticulated rules”and“articulated rules”.The study finds that state-owned capital participation significantly reduces the debt financing costs of private enterprises and expands the scale of their debt financing.This conclusion remains valid after a series of endogeneity and robustness tests.Further analysis of the mechanism reveals that state-owned capital participation improves the debt financing of private enterprises through multiple channels:Enhancing their social reputation,mitigating the“statistical bias”they face,optimizing their information quality,and reducing the“shareholder-creditor”agency problems.This paper conceptualizes these benefits as the“complementary advantages of heterogeneous shareholders”.This not only constructs a theoretical framework for“reverse mixed-ownership reform”but also better narrates the Chinese story of“mixed-ownership reform”by adopting a more universally applicable theory of equity structure.Additionally,the paper supplements existing research on the macro-and meso-level relationship between the government and the market by exploring the government’s positive role at the micro-level. 展开更多
关键词 Mixed-ownership reform reverse mixed-ownership reform state-owned capital debt financing heterogeneous shareholders
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National Soil Organic Carbon Stocks Inventories under Different Mangrove Forest Types in Gabon
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作者 Rolf Gaël Mabicka Obame Neil-Yohan Musadji +5 位作者 Jean Hervé Mve Beh Lydie-Stella Koutika Jean Aubin Ondo Farrel Nzigou Boucka Michel Mbina Mounguengui Claude Geffroy 《Open Journal of Forestry》 2024年第2期127-140,共14页
Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear... Gabonese’s estuary is an important coastal mangrove setting and soil plays a key role in mangrove carbon storage in mangrove forests. However, the spatial variation in soil organic carbon (SOC) storage remain unclear. To address this gap, determining the SOC spatial variation in Gabonese’s estuarine is essential for better understanding the global carbon cycle. The present study compared soil organic carbon between northern and southern sites in different mangrove forest, Rhizophora racemosa and Avicennia germinans. The results showed that the mean SOC stocks at 1 m depth were 256.28 ± 127.29 MgC ha<sup>−</sup><sup>1</sup>. Among the different regions, SOC in northern zone was significantly (p p < 0.001). The deeper layers contained higher SOC stocks (254.62 ± 128.09 MgC ha<sup>−</sup><sup>1</sup>) than upper layers (55.42 ± 25.37 MgC ha<sup>−</sup><sup>1</sup>). The study highlights that low deforestation rate have led to less CO<sub>2</sub> (705.3 Mg CO<sub>2</sub>e ha<sup>−</sup><sup>1</sup> - 922.62 Mg CO<sub>2</sub>e ha<sup>−</sup><sup>1</sup>) emissions than most sediment carbon-rich mangroves in the world. These results highlight the influence of soil texture and mangrove forest types on the mangrove SOC stocks. The first national comparison of soil organic carbon stocks between mangroves and upland tropical forests indicated SOC stocks were two times more in mangroves soils (51.21 ± 45.00 MgC ha<sup>−</sup><sup>1</sup>) than primary (20.33 ± 12.7 MgC ha<sup>−</sup><sup>1</sup>), savanna and cropland (21.71 ± 15.10 MgC ha<sup>−</sup><sup>1</sup>). We find that mangroves in this study emit lower dioxide-carbon equivalent emissions. This study highlights the importance of national inventories of soil organic carbon and can be used as a baseline on the role of mangroves in carbon sequestration and climate change mitigation but the variation in SOC stocks indicates the need for further national data. 展开更多
关键词 Mangroves Forest Soil Organic Carbon stocks Rizophora Racemose Avicenia germinans GABON
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Research on Mixed Ownership Reform of State-Owned Enterprises from the Perspective of Marxist Political Economy
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作者 Honghong Lu 《Proceedings of Business and Economic Studies》 2024年第5期61-67,共7页
Under China’s socialist system,state-owned enterprises are key forces driving the economic trajectory and providing strong momentum.These enterprises not only bear the crucial responsibility of advancing the process ... Under China’s socialist system,state-owned enterprises are key forces driving the economic trajectory and providing strong momentum.These enterprises not only bear the crucial responsibility of advancing the process of national modernization but also serve as the core of the national economic lifeline through their irreplaceable status and function amidst changing times.In the new era,with the advent of the technological revolution and the wave of globalization,state-owned enterprises face unprecedented opportunities and challenges.As a significant aspect of state-owned enterprise reform,the mixed ownership reform is not only a transformation in the structure of enterprise ownership but also a reflection of China’s broader,comprehensive reform efforts.By deeply advancing this reform,it will help optimize the allocation of state-owned assets and significantly boost technological and management innovation within state-owned enterprises,ensuring their competitiveness in the intense market environment.Therefore,this paper will conduct an in-depth analysis of the mixed ownership reform of state-owned enterprises from the perspective of Marxist political economy. 展开更多
关键词 Marxist political economy state-owned enterprise reform Mixed ownership
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Internal Control Management and Risk Prevention Measures of State-Owned Enterprises
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作者 Bing Liu 《Journal of Electronic Research and Application》 2024年第3期1-6,共6页
As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an... As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an important part of enterprise management,internal control management plays an irreplaceable role.Especially in the current domestic and international economic situation is complex and changeable,market competition is increasingly fierce environment,to strengthen the internal control management of state-owned enterprises and risk prevention measures is particularly important.This paper starts with the importance of internal control management and risk prevention for state-owned enterprises,and analyzes the problems and strategies in the internal control management and risk prevention of state-owned enterprises,in order to build a more comprehensive and efficient risk management system for state-owned enterprises to adapt to the ever-changing market environment and realize sustainable development. 展开更多
关键词 state-owned enterprises Internal control management Risk prevention
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STUDY OF REENGINEERING THE STOCK EQUITY STRUCTURE IN CHINESE STATE-OWNED ENTERPRISE REFORM
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作者 朱秀文 杨嘉钦 《Transactions of Tianjin University》 EI CAS 2001年第2期86-92,共7页
In this paper,it is first briefly described the basic situation and current policies of state owned enterprise reform in China.Then the major issues in the reform process are identified,the possible solutions in term... In this paper,it is first briefly described the basic situation and current policies of state owned enterprise reform in China.Then the major issues in the reform process are identified,the possible solutions in terms of reengineering stock equity structure and state share circulation are discussed,and finally some suggestions are made for the further state owned enterprise reform.Basing on the theory on the modern corporation system,relevant experiences of market economy nations and the practice of Chinese enterprise system reform.The approaches to determine the proportion of state share in the future corporations are proposed.Since the public ownership is not ideologically appropriate,the establishment of social security fund and mutual fund investment companies are suggested as new and acceptable pattern of public ownership.It is believed that these companies will be the major institutional shareholders in the future corporations.Their stock equity structure would mainly consist of institutional shareholders,which will be both consistent with international norms of modern corporations and with socialist public ownership with Chinese characteristics. 展开更多
关键词 state owned enterprise corporation system reform stock equity structure institutional investors
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Exploiting Data Science for Measuring the Performance of Technology Stocks
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作者 Tahir Sher Abdul Rehman +1 位作者 Dongsun Kim Imran Ihsan 《Computers, Materials & Continua》 SCIE EI 2023年第9期2979-2995,共17页
The rise or fall of the stock markets directly affects investors’interest and loyalty.Therefore,it is necessary to measure the performance of stocks in the market in advance to prevent our assets from suffering signi... The rise or fall of the stock markets directly affects investors’interest and loyalty.Therefore,it is necessary to measure the performance of stocks in the market in advance to prevent our assets from suffering significant losses.In our proposed study,six supervised machine learning(ML)strategies and deep learning(DL)models with long short-term memory(LSTM)of data science was deployed for thorough analysis and measurement of the performance of the technology stocks.Under discussion are Apple Inc.(AAPL),Microsoft Corporation(MSFT),Broadcom Inc.,Taiwan Semiconductor Manufacturing Company Limited(TSM),NVIDIA Corporation(NVDA),and Avigilon Corporation(AVGO).The datasets were taken from the Yahoo Finance API from 06-05-2005 to 06-05-2022(seventeen years)with 4280 samples.As already noted,multiple studies have been performed to resolve this problem using linear regression,support vectormachines,deep long short-termmemory(LSTM),and many other models.In this research,the Hidden Markov Model(HMM)outperformed other employed machine learning ensembles,tree-based models,the ARIMA(Auto Regressive IntegratedMoving Average)model,and long short-term memory with a robust mean accuracy score of 99.98.Other statistical analyses and measurements for machine learning ensemble algorithms,the Long Short-TermModel,and ARIMA were also carried out for further investigation of the performance of advanced models for forecasting time series data.Thus,the proposed research found the best model to be HMM,and LSTM was the second-best model that performed well in all aspects.A developedmodel will be highly recommended and helpful for early measurement of technology stock performance for investment or withdrawal based on the future stock rise or fall for creating smart environments. 展开更多
关键词 Machine learning data science smart environments stocks movement deep learning stock marketing
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Integrating remote sensing and 3-PG model to simulate the biomass and carbon stock of Larix olgensis plantation
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作者 Yu Bai Yong Pang Dan Kong 《Forest Ecosystems》 SCIE CSCD 2024年第4期543-555,共13页
Accurate estimations of biomass and its temporal dynamics are crucial for monitoring the carbon cycle in forest ecosystems and assessing forest carbon sequestration potentials.Recent studies have shown that integratin... Accurate estimations of biomass and its temporal dynamics are crucial for monitoring the carbon cycle in forest ecosystems and assessing forest carbon sequestration potentials.Recent studies have shown that integrating process-based models(PBMs)with remote sensing data can enhance simulations from stand to regional scales,significantly improving the ability to simulate forest growth and carbon stock dynamics.However,the utilization of PBMs for large-scale simulation of larch carbon storage distribution is still limited.In this study,we applied the parameterized 3-PG(Physiological Principles Predicting Growth)model across the Mengjiagang Forest Farm(MFF)to make broad-scale predictions of the biomass and carbon stocks of Larix olgensis plantation.The model was used to simulate average diameter at breast height(DBH)and total biomass,which were later validated with a wide range of observation data including sample plot data,forest management inventory data,and airborne laser scanning data.The results showed that the 3-PG model had relatively high accuracy for predicting both DBH and total biomass at stand and regional scale,with determination coefficients ranging from 0.78 to 0.88.Based on the estimation of total biomass,we successfully produced a carbon stock map of the Larix olgensis plantation in MFF with a spatial resolution of 20 m,which helps with relevant management advice.These findings indicate that the integration of 3-PG model and remote sensing data can well predict the biomass and carbon stock at regional and even larger scales.In addition,this integration facilitates the evaluation of forest carbon sequestration capacity and the development of forest management plans. 展开更多
关键词 3-PG model LARCH BIOMASS Carbon stock ALS
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Research on Influencing Factors and Countermeasures of Risk Control of State-Owned Enterprises under the Background of Big Data
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作者 Fengyan Wang Ziyu Hou +1 位作者 Ronaldo Juanatas Jasmin Niguidula 《Proceedings of Business and Economic Studies》 2023年第6期128-133,共6页
This study explores the risk control and response strategies of state-owned enterprises in the context of big data.Global economic uncertainty poses new challenges to state-owned enterprises,necessitating innovative r... This study explores the risk control and response strategies of state-owned enterprises in the context of big data.Global economic uncertainty poses new challenges to state-owned enterprises,necessitating innovative risk management approaches.This article proposes response strategies from four key aspects:establishing a proactive risk management culture,building a foundation in technology and data,conducting big data-driven risk analysis,and implementing predictive analysis and real-time monitoring.State-owned enterprises can foster a proactive risk management culture by cultivating employee risk awareness,demonstrating leadership,and establishing transparency and open communication.Additionally,data integration and analysis,leveraging the latest technology,are crucial factors that can help companies better identify risks and opportunities. 展开更多
关键词 state-owned enterprises Risk management Big data Risk control
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Impact of State-Owned Capital Participation on ESG Performance of Private Enterprises
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作者 Xiongwei Wu 《Proceedings of Business and Economic Studies》 2023年第6期121-127,共7页
As global investors and stakeholders increasingly prioritize environmental,social,and governance(ESG)performance,corporate social responsibility and sustainability have become crucial factors in determining corporate ... As global investors and stakeholders increasingly prioritize environmental,social,and governance(ESG)performance,corporate social responsibility and sustainability have become crucial factors in determining corporate success.In the context of China’s robust economy,the involvement of state-owned capital exerts a profound impact on the ESG performance of private enterprises.This paper,starting from the perspective of ESG,analyzes how state-owned capital participation influences the ESG performance of private enterprises.Additionally,it proposes recommendations for the involvement of state-owned enterprises in private enterprises,aiming to foster the sustainable development of private enterprises and enhance their social responsibility. 展开更多
关键词 state-owned capital Private enterprises ESG Sense of social responsibility
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Carbon stock estimation in halophytic wooded savannas of Uruguay:An ecosystem approach
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作者 Andres Baietto Andres Hirigoyen +3 位作者 Carolina Toranza Franco Schinato Maximiliano Gonzalez Rafael Navarro Cerrillo 《Forest Ecosystems》 SCIE CSCD 2024年第4期580-589,共10页
Savannas constitute a mixture of trees and shrub patches with a more continuous herbaceous understory.The contribution of this biome to the soil organic carbon(SOC)and above-ground biomass(AGB)carbon(C)stock globally ... Savannas constitute a mixture of trees and shrub patches with a more continuous herbaceous understory.The contribution of this biome to the soil organic carbon(SOC)and above-ground biomass(AGB)carbon(C)stock globally is significant.However,they are frequently subjected to land use changes,promoting increases in CO_(2) emissions.In Uruguay,subtropical wooded savannas cover around 100,000 ha,of which approximately 28%is circumscribed to sodic soils(i.e.,subtropical halophytic wooded savannas).Nevertheless,there is little background about the contribution of each ecosystem component to the C stock as well as site-specific allometric equations.The study was conducted in 5 ha of subtropical halophytic wooded savannas of the national protected area Esteros y Algarrobales del Rio Uruguay.This work aimed to estimate the contribution of the main ecosystem components(e.g.,soil,trees,shrubs,and herbaceous plants)to the C stock.Site-specific allometric equations for the most frequent tree species and shrub genus were fitted based on basal diameter(BD)and total height(H).The fitted equations accounted for between 77%and 98%of the aerial biomass variance of Netuma affinis and Vachellia caven.For shrubs(Baccharis sp.),the adjusted equation accounted for 86%of total aerial biomass.C stock for the entire system was 116.71±11.07 Mg·ha^(-1),of which 90.7%was allocated in the soil,8.3%in the trees,0.8%in the herbaceous plants,and 0.2%in the shrubs.These results highlight the importance of subtropical halophytic wooded savannas as C sinks and their relevance in the mitigation of global warming under a climate change scenario. 展开更多
关键词 Carbon stock Climate change Biomass modeling Sodic soils
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Growth, Population Parameters and Stock Status of Sarotherodon galilaeus in Samandeni Reservoir, Burkina Faso
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作者 Nomwine Da Raymond Ouedraogo +1 位作者 Mahamoudou Minoungou Adama Oueda 《Open Journal of Ecology》 2024年第4期257-273,共17页
Mango tilapia, Sarotherodon galilaeus is one of the most caught fish species in the Samandeni multi-species fishing sites of which, few data on its biology and exploitation are available. The study aimed to Assess the... Mango tilapia, Sarotherodon galilaeus is one of the most caught fish species in the Samandeni multi-species fishing sites of which, few data on its biology and exploitation are available. The study aimed to Assess the stock status of S. galilaeus. Sampling was conducted from March, 2021 to February 2022 based on commercial fish catches to analyze growth parameters, first sexual maturity size and harvest status of the stock. A total of 572 specimens including 297 females and 275 males were examined. The stock assessment was performed by using the Length based Bayesian method of Biomass (LBB) and that of growth by the ELEFAN method. The growth parameters showed a seasonality of growth and females appeared to grow faster than males. On the other hand, males had a greater asymptotic length than females. Results on the estimated length of fish at first maturity showed that females firstly reached the maturity compared to males. The relative biomass (B/B<sub>0</sub>) estimated for the stock was higher than the relative biomass that produces maximum sustainable yield (B<sub>MSY</sub>/B<sub>0</sub>) indicating healthy biomass. In addition, the length at first sexual maturity was less than the length at the first catch, indicating the absence of overfishing of growth. In addition, extending the study to the various stocks of the reservoir would be important for the sustainable management of the Samandeni high economic fishing area. 展开更多
关键词 GROWTH stock Status Sarotherodon galilaeus Samandeni Reservoir MATURITY
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Tree mycorrhizal associations determine how biodiversity,large trees,and environmental factors drive aboveground carbon stock in temperate forests
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作者 Yue Chen Zikun Mao +2 位作者 Jonathan A.Myers Jinghua Yu Xugao Wang 《Forest Ecosystems》 SCIE CSCD 2024年第4期448-456,共9页
Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these f... Biodiversity,large trees,and environmental conditions such as climate and soil have important effects on forest carbon stocks.However,recent studies in temperate forests suggest that the relative importance of these factors depends on tree mycorrhizal associations,whereby large-tree effects may be driven by ectomycorrhizal(EM)trees,diversity effects may be driven by arbuscular mycorrhizal(AM)trees,and environment effects may depend on differential climate and soil preferences of AM and EM trees.To test this hypothesis,we used forest-inventory data consisting of over 80,000 trees from 631 temperate-forest plots(30 m×30 m)across Northeast China to examine how biodiversity(species diversity and ecological uniqueness),large trees(top 1%of tree diameters),and environmental factors(climate and soil nutrients)differently regulate aboveground carbon stocks of AM trees,EM trees,and AM and EM trees combined(i.e.total aboveground carbon stock).We found that large trees had a positive effect on both AM and EM tree carbon stocks.However,biodiversity and environmental factors had opposite effects on AM vs.EM tree carbon stocks.Specifically,the two components of biodiversity had positive effects on AM tree carbon stocks,but negative effects on EM tree carbon stocks.Environmental heterogeneity(mean annual temperature and soil nutrients)also exhibited contrasting effects on AM and EM tree carbon stocks.Consequently,for the total carbon stock,the positive large-tree effect far surpasses the diversity and environment effect.This is mainly because when integrating AM and EM tree carbon stock into total carbon stock,the opposite diversity-effect(also environment-effect)on AM vs.EM tree carbon stock counteracts each other while the consistent positive large-tree effect on AM and EM tree carbon stock is amplified.In summary,this study emphasized a mycorrhizal viewpoint to better understand the determinants of overarching aboveground carbon profile across regional forests. 展开更多
关键词 BIODIVERSITY Ecological uniqueness Environment heterogeneity Large trees Mycorrhizal associations Tree carbon stock
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Transcriptional regulation of MdPIN7 by MdARF19 during gravityinduced formation of adventitious root GSA in self-rooted apple stock
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作者 Zenghui Wang Xuemei Yang +5 位作者 Linyue Hu Wei Liu Lijuan Feng Xiang Shen Yanlei Yin Jialin Li 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第5期1073-1084,共12页
Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the... Self-rooted apple stock is widely used for apple production.However,the shallowness of the adventitious roots in self-rooted apple stock leads to poor performance in the barren orchards of China.This is because of the considerable difference in the development of a gravitropic set-point angle(GSA)between self-rooted apple stock and seedling rootstock.Therefore,it is crucial to study the molecular mechanism of adventitious root GSA in self-rooted apple stock for breeding self-rooted and deep-rooted apple rootstock cultivars.An apple auxin response factor MdARF19 functioned to establish the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals.MdARF19 bound directly to the MdPIN7 promoter,activating its transcriptional expression and thus regulating the formation of the adventitious root GSA in 12-2 self-rooted apple stock.However,MdARF19 influenced the expression of auxin efflux carriers(MdPIN3 and MdPIN10)and the establishment of adventitious root GSA of self-rooted apple stock in response to gravity signals by direct activation of MdFLP.Our findings provide new information on the transcriptional regulation of MdPIN7 by auxin response factor MdARF19 in the regulation of the adventitious root GSA of self-rooted apple stock in response to gravity and auxin signals. 展开更多
关键词 APPLE Self-rooted stock GRAVITY MdARF19 MdPIN7 Gravitropic set-point angle Transcriptional regulation
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Structured Multi-Head Attention Stock Index Prediction Method Based Adaptive Public Opinion Sentiment Vector
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作者 Cheng Zhao Zhe Peng +2 位作者 Xuefeng Lan Yuefeng Cen Zuxin Wang 《Computers, Materials & Continua》 SCIE EI 2024年第1期1503-1523,共21页
The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment ... The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits. 展开更多
关键词 Public opinion sentiment structured multi-head attention stock index prediction deep learning
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The Impact of Short Selling Disclosure Regulatory Constraint on the Lending Market and Stock Ownership
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作者 Geoffrey Ducournau Jinliang Li +2 位作者 Yan Li Zigan Wang Qie Ellie Yin 《Journal of Modern Accounting and Auditing》 2024年第3期99-114,共16页
We examine the impact of the short sell disclosure(SSD)regime on the stock lending market and investor behaviors,employing a staggered difference-indifference(DiD)methodology.Our research reveals that the introduction... We examine the impact of the short sell disclosure(SSD)regime on the stock lending market and investor behaviors,employing a staggered difference-indifference(DiD)methodology.Our research reveals that the introduction of the disclosure regime enhances market transparency,resulting in a diminished appeal of stock ownership in the lending market for active investors.This shift is accompanied by a reduction in information leakage risks and longer loan durations.Specifically,our analysis reveals a significant decrease in the risk of loan recall by 4.87%,accompanied by an average increase of 23.72%in loan duration for short selling activities.Furthermore,the cost associated with short-sell disclosure causes a decline in both lending supply and short demand. 展开更多
关键词 short sell disclosure stock equity lending market stock ownership
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The changes in soil organic carbon stock and quality across a subalpine forest successional series
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作者 Fei Li Zhihui Wang +3 位作者 Jianfeng Hou Xuqing Li Dan Wang Wanqin Yang 《Forest Ecosystems》 SCIE CSCD 2024年第4期423-433,共11页
Soil organic carbon(SOC)affects the function of terrestrial ecosystem and plays a vital role in global carbon cycle.Yet,large uncertainty still existed regarding the changes in SOC stock and quality with forest succes... Soil organic carbon(SOC)affects the function of terrestrial ecosystem and plays a vital role in global carbon cycle.Yet,large uncertainty still existed regarding the changes in SOC stock and quality with forest succession.Here,the stock and quality of SOC at 1-m soil profile were investigated across a subalpine forest series,including shrub,deciduous broad-leaved forest,broadleaf-conifer mixed forest,middle-age coniferous forest and mature coniferous forest,which located at southeast of Tibetan Plateau.The results showed that SOC stock ranged from 9.8 to29.9 kg·m^(-2),and exhibited a hump-shaped response pattern across the forest successional series.The highest and lowest SOC stock was observed in the mixed forest and shrub forest,respectively.The SOC stock had no significant relationships with soil temperature and litter stock,but was positively correlated with wood debris stock.Meanwhile,the average percentages of polysaccharides,lignins,aromatics and aliphatics based on FTIR spectroscopy were 79.89%,0.94%,18.87%and 0.29%,respectively.Furthermore,the percentage of polysaccharides exhibited an increasing pattern across the forest successional series except for the sudden decreasing in the mixed forest,while the proportions of lignins,aromatics and aliphatics exhibited a decreasing pattern across the forest successional series except for the sudden increasing in the mixed forest.Consequently,the humification indices(HIs)were highest in the mixed forest compared to the other four successional stages,which means that the SOC quality in mixed forest was worse than other successional stages.In addition,the SOC stock,recalcitrant fractions and HIs decreased with increasing soil depth,while the polysaccharides exhibited an increasing pattern.These findings demonstrate that the mixed forest had higher SOC stock and worse SOC quality than other successional stages.The high proportion of SOC stock(66%at depth of 20-100 cm)and better SOC quality(lower HIs)indicate that deep soil have tremendous potential to store SOC and needs more attention under global chan ge. 展开更多
关键词 Forest successional series Soil organic cubon stock Molecular composition Humification indices Soil organic carbon quality
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Design Strategies and Practice Paths for Improving Urban Quality in the Stock Era
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作者 Li Tianfei Zhou Xiaotian +1 位作者 Han Shengsheng Liu Yuxuan 《Journal of Landscape Research》 2024年第2期18-24,共7页
In the middle and later stages of urbanization development,the growth of the real estate industry will stagnate,and urban renewal will become the mainstream.With the advancement of urban renewal,there are still proble... In the middle and later stages of urbanization development,the growth of the real estate industry will stagnate,and urban renewal will become the mainstream.With the advancement of urban renewal,there are still problems in improving the quality of cities in the stock era and their design strategies.This paper analyzed the Linping Old City organic renewal project and the Xishui River ecological governance project in the stock era of urban quality improvement by sorting out the current development status,historical background,planning types,and design strategies of quality improvement in the stock era from the perspective of urban renewal,combining with project overview,main problems,design methods,and design content.Urban renewal is the leading direction for promoting urban development and construction on a global scale,and countries formulate different plans and practices based on their local characteristics.Urban renewal strategies should be diversified,and focus on livable environments,urban characteristics,etc.,while considering human factors,green innovation,etc.,in order to achieve smart community management and enhance the economic and social benefits brought by urban attractiveness.For successful cases such as the Linping Old City and Xishui River ecological governance project,corresponding urban quality improvement strategies and implementation plans should be formulated according to local conditions,with emphasis on social participation and people’s livelihood improvement.This study can help urban planning pay more attention to rational utilization and upgrading of existing urban resources,adapt to the current urban development situation,and promote sustainable urban development. 展开更多
关键词 stock era Organic renewal Ecological governance Linping Old City Xishui River
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Stock Type Prediction Based on Multiple Machine Learning Methods
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作者 Zhonger Zhu Wansheng Wang 《Journal of Intelligent Learning Systems and Applications》 2024年第3期242-261,共20页
Stocks in the Chinese stock market can be divided into ST stocks and normal stocks, so to prevent investors from buying potential ST stocks, this paper first performs SMOTEENN oversampling data preprocessing for the S... Stocks in the Chinese stock market can be divided into ST stocks and normal stocks, so to prevent investors from buying potential ST stocks, this paper first performs SMOTEENN oversampling data preprocessing for the ST stock category, and selects 139 financial indicators and technical factor as predictive features. Then, it combines the Boruta algorithm and Copula entropy method for feature selection, effectively improving the machine learning model’s performance in ST stock classification, with the AUC values of the two models reaching 98% on the test set. In the model selection and optimization, this paper uses six major models, including logistic regression, XGBoost, AdaBoost, LightGBM, Catboost, and MLP, for modeling and optimizes them using the Optuna framework. Ultimately, XGBoost model is selected as the best model because its AUC value exceeds 95% and its running time is less. Finally, the XGBoost model is explained using the SHAP theory and the interaction between features is discovered, further improving the model’s accuracy and AUC value by about 0.6%, verifying the effectiveness of the model. 展开更多
关键词 stock Classification Boruta Algorithm COPULA Machine Learning INTERACTION
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Comparative Analysis of Machine Learning Models for Stock Price Prediction: Leveraging LSTM for Real-Time Forecasting
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作者 Bijay Gautam Sanif Kandel +1 位作者 Manoj Shrestha Shrawan Thakur 《Journal of Computer and Communications》 2024年第8期52-80,共29页
The research focuses on improving predictive accuracy in the financial sector through the exploration of machine learning algorithms for stock price prediction. The research follows an organized process combining Agil... The research focuses on improving predictive accuracy in the financial sector through the exploration of machine learning algorithms for stock price prediction. The research follows an organized process combining Agile Scrum and the Obtain, Scrub, Explore, Model, and iNterpret (OSEMN) methodology. Six machine learning models, namely Linear Forecast, Naive Forecast, Simple Moving Average with weekly window (SMA 5), Simple Moving Average with monthly window (SMA 20), Autoregressive Integrated Moving Average (ARIMA), and Long Short-Term Memory (LSTM), are compared and evaluated through Mean Absolute Error (MAE), with the LSTM model performing the best, showcasing its potential for practical financial applications. A Django web application “Predict It” is developed to implement the LSTM model. Ethical concerns related to predictive modeling in finance are addressed. Data quality, algorithm choice, feature engineering, and preprocessing techniques are emphasized for better model performance. The research acknowledges limitations and suggests future research directions, aiming to equip investors and financial professionals with reliable predictive models for dynamic markets. 展开更多
关键词 stock Price Prediction Machine Learning LSTM ARIMA Mean Squared Error
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Exploring the Relationship Between Patent Forward Citation and Stock Return Rate Using Empirical Data of China Stock Market
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作者 Hong-Wen Tsai Hui-Chung Che 《Management Studies》 2024年第2期67-83,共17页
A novel indicator called price-citation was proposed.Based on the company integrated patent database of China listed companies of common stocks(A-shares)with the stock price and the stock return rate data,more than tw... A novel indicator called price-citation was proposed.Based on the company integrated patent database of China listed companies of common stocks(A-shares)with the stock price and the stock return rate data,more than two thousand of A-shares from 2017 to 2020 were selected.The effect of the traditional patent forward citation and the price-citation for discriminating the stock return rate was thoroughly analyzed via ANOVA.The A-shares of forward citation counts above the average showed higher stock return rate means than the A-shares having patents but receiving no forward citations.The price-citation,combining both the financial and patent attributes,defined as the multiplication of the current stock price and the currently receiving forward citation count,showed its excellence in discriminating the stock return rate.The A-shares of higher price-citation showed significantly higher stock return rate means while the A-shares of lower price-citation showed significantly lowest stock return rate means.The price-citation effect had not been changed by COVID-19 though COVID-19 affected the social and economic environment to a considerable extent in 2020. 展开更多
关键词 China A-share PATENT ANOVA stock return rate forward citation price-citation
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