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The Connotation and Path Choice of Socialist Core Value System
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作者 Zhou Hui Chen Li 《学术界》 CSSCI 北大核心 2020年第10期201-208,共8页
The socialist core value system(scVs)is a multi-layered systematic logical structure:with Marxism as the backbone which determines the fundamental nature of this value system;the common ideal of socialism with Chinese... The socialist core value system(scVs)is a multi-layered systematic logical structure:with Marxism as the backbone which determines the fundamental nature of this value system;the common ideal of socialism with Chinese characteristics as the embodiment of its goals;national spirit and the spirit of the times as its spiritual power;and the concept of honor as its moral foundation.SCVS construction focuss on practice,and its implementation includes the following three aspects;focusing on people's livelitood to increase the attractiveness of sCVs;vigorously developing productivity and expanding the material basis of the guiding functions of SCVS;and establishing an effective mechanism for publicity and education.While practicing SCVs,objective laws need to be followed and public enthusiasm need to be mobilized,path choice for development subjects and objective practice need to be highlighted,and policy system need to be improved gradually in practice,so that a linkage mechanism for all people to participate can be formed. 展开更多
关键词 socialist core value system(ScVS) value connotation connotation of path choice
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The Anime Subculture and Socialist Core Value System
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作者 Lihua Wang 《International English Education Research》 2014年第10期31-33,共3页
The rise of the anirne subculture assembles the huge youth groups in the construction of the socialist core value system, and provides a new carrier and injected into the innovative dynamic. At the same time, their pe... The rise of the anirne subculture assembles the huge youth groups in the construction of the socialist core value system, and provides a new carrier and injected into the innovative dynamic. At the same time, their perverse behavior and exaggerated style of dress and the strange language constitute the alienation and challenges of a core value system. It should strengthen the ideological review and classification management, with the criticism of the mainstream media to enhance the vigilance of the community, as well as through commercial activities to digest rebel style, which is the effective way to promote the core value system. 展开更多
关键词 Anime Subculture Socialist Core value system STYLE Subcultural Capital Incorporated
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A Recognized Value System among Nurses Working in Poland
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作者 Beata Bajurna Anna Galeba Jerzy TMarcinkowski 《Open Journal of Nursing》 2015年第1期68-76,共9页
Aim of this work was to present a study indicating the recognized system of values of nursing units in healthcare entities in Poland. Professionally active nurses (249) employed in medicinal entities were subjects in ... Aim of this work was to present a study indicating the recognized system of values of nursing units in healthcare entities in Poland. Professionally active nurses (249) employed in medicinal entities were subjects in the study. A random selection of individuals was applied in the study, and the participation in the research was declared by respondents consent to participate in it. A survey was used as the main form of measurement, and it was divided into direct and indirect survey. A standardized Rokeach’s scale of values [1] [2] consisting of two collections, each of which included 18 single values, was used. They were ranked by tested individuals according to the hierarchy of their values which allowed for recognizing which are the most important for them. Kruskal-Wallis’s test was applied in the study. Results: The social position is the most important value for nurses working in the district medical entities. For those working in the regional medical units, the most appreciated value is being ambitious, whereas in the clinical self-esteem. The socio-demographic data such as age, length of service, levels of education differentiate assessments of each recognized values in the group of nurses. The women between 31 and 40 consider being ambitious as the most important value, between 41 and 50 responsibility and between 20 and 30 self-esteem;responsibility is the most appreciated value for people with 21 - 25 years of experience because the older and more experienced the nurse is, the stronger her sense of responsibility becomes. A social position was appreciated the most by the nurses holding a nursing degree. Conclusions: There have been significant differences in terms of accepted values between nurses working in the district, provincial and clinical medical entities. Socio-demographic data such as age, length of service, education levels differentiate assessment of each recognized value in the group of nurses. 展开更多
关键词 value system Nurses Healthcare Entity
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A Comparison of the Influence of World Views and Value Systems on Behavior between Chinese and Americans
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作者 李启宇 《海外英语》 2016年第23期170-172,共3页
This thesis compares the differences between Chinese and Americans in terms of their world view and value systems,and analyzes how these differences affect the behavioral patterns of people with different cultural bac... This thesis compares the differences between Chinese and Americans in terms of their world view and value systems,and analyzes how these differences affect the behavioral patterns of people with different cultural backgrounds. It also proposes some suggestions to overcome the difference. As globalization is quickening its pace, world views and value systems, as the core of culture, profoundly affect people's pattern of behavior. A deeper understanding and consciousness of the differences may promote a more effective communication between different cultural backgrounds. This thesis compares the differences between Chinese and US cultures from three perspectives: the different world view between Chinese and Americans, the different value systems between Chinese and Americans and how the two affect their behaviors. And some suggestions are also given. 展开更多
关键词 world view value system BEHAVIOR
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The Existence and Multiplicity of Solutions for Singular Boundary Value Systems with p-Laplacian
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作者 Zengxia Cai 《Journal of Applied Mathematics and Physics》 2015年第4期411-416,共6页
This paper presents sufficient conditions for the existence of positive solutions for the fourth-order boundary value problem system with p-Laplacian operator. The existence of single or multiple positive solutions fo... This paper presents sufficient conditions for the existence of positive solutions for the fourth-order boundary value problem system with p-Laplacian operator. The existence of single or multiple positive solutions for the system is showed through the fixed point index theory in cones under some assumptions. 展开更多
关键词 Coupled SINGULAR BOUNDARY value Problem POSITIVE Solution Fixed Point Index THEOREM
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Research on Present Situation and Countermeasure of Identity Recognition among Current College Students towards Socialist Core Value System
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作者 Xue Lei 《International English Education Research》 2015年第1期69-71,共3页
The value identity emphasizes the harmony and consistency between the different value concepts. In general, it includes three stages, namely cognition, internalization and externalization. By the investigation on the ... The value identity emphasizes the harmony and consistency between the different value concepts. In general, it includes three stages, namely cognition, internalization and externalization. By the investigation on the present situation of college students' socialist core value system identity, it can be found that, at present, there is a good development momentum of our country's higher vocational school students' thoughts in general. But it also exists some problems that can't be ignored. Therefore, the top priority should be focused on the students' physical and mental characteristics. We should reform the current education methods gradually, steadily enhance the college students' identity, emotion and behavior cognition of socialist core value system, and gradually strengthen the ideological construction of college students, so as to make them better serve the socialist modernization. 展开更多
关键词 College Students Socialist Core values IDENTITY PRACTICE
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Resilience planning for urban ecosystems in the Himalayas:Ecosystem service value decline and network vulnerabilities in Lhasa
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作者 Jiarui Zhang Liyuan Qian +2 位作者 Guangyu Wang Migmar Wangdwei Qingtao Zhu 《Ecological Frontiers》 2026年第1期227-241,共15页
Lhasa,one of the world's highest cities,confronts the challenge of harmonizing cultural heritage preservation with ecological protection.Assessing the spatiotemporal dynamics of ecosystem service value(ESV)in its ... Lhasa,one of the world's highest cities,confronts the challenge of harmonizing cultural heritage preservation with ecological protection.Assessing the spatiotemporal dynamics of ecosystem service value(ESV)in its central urban area is therefore critical for informing future urban planning and land management.This study systematically analyzed land use evolution,the spatiotemporal characteristics of ecosystem services,and ecological network construction within Lhasa's central urban area.It integrated multi-source data,including Landsat remote sensing imagery from 2000,2010,and 2023,with multiple modeling methods such as the InVEST model,MaxEnt for cultural service assessment,the Minimum Cumulative Resistance(MCR)model,and circuit theory.Based on these analyses,optimization strategies were proposed.The results indicate that from 2000 to 2023,areas of cultivated land,grassland,and water bodies decreased by 7.47%,6.85%,and 0.68%,respectively,while wetland and forest areas expanded by 1.44%and 0.64%.Construction land exhibited significant expansion(12.94%),leading to an overall ESV reduction of 462.8×10^(5)yuan.Vegetation coverage was identified as the pivotal factor influencing ESV distribution,with higher values concentrated in the Lhasa River Basin and near the Lhalu Wetland,diminishing towards the urban core.Furthermore,spatial autocorrelation analysis revealed significant positive spatial clustering,with low-low aggregation in the eastern and central regions and high-high aggregation in the Lhasa River Basin and its surrounding water bodies.Moreover,based on a comprehensive ecosystem service assessment,11 ecological source sites were identified,primarily in the southwestern mountains and northeastern foothills.A comprehensive resistance surface,incorporating factors such as elevation,Normalized Difference Vegetation Index(NDVI),and land use,facilitated the extraction of 23 potential ecological corridors totaling 124.96 km in length.Topological network analysis indicated high redundancy and connectivity;however,marginal source sites relying on single connections exhibited significant vulnerability to rupture.Additionally,the application of circuit theory identified 30 ecological pinch points(current density≥1.5 A/km^(2))and 23 obstacle points,revealing significant blockages to ecological flow along the Qinghai-Xizang Highway,within the old city,and in other areas of high-intensity human activity.To address the identified network deficiencies—‘scattered cores,fragmented corridors,and insufficient resilience’—this study proposes an optimization strategy conceptualized as‘one vein,three corridors,and multiple cores’.Recommendations for enhancing network resilience include the delineation of ecological protection red lines,the integration of plateau-adapted technologies,and the fostering of community governance mechanisms.This approach aims to provide a scientific basis for constructing an ecological security pattern and promoting sustainable development in plateau cities.Ultimately,this research contributes to the enhancement of ecological well-being in the Himalayan region. 展开更多
关键词 Plateau urbanization Ecosystem service value Ecological network Ecological corridor Llasa
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Forecasting ecosystem service values in South China's fragile mountain regions:a multi-scenario analysis with adaptive land use valuation
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作者 LIAO Zhaoyang YU De +3 位作者 RAN Penglai ZHENG Defu SHANG Guiduo TAN Jie 《Journal of Mountain Science》 2026年第2期813-827,共15页
Numerous economically underdeveloped and ecologically fragile areas in southern China's mountainous regions face increasing challenges in achieving sustainable development. A comparative analysis of ecosystem serv... Numerous economically underdeveloped and ecologically fragile areas in southern China's mountainous regions face increasing challenges in achieving sustainable development. A comparative analysis of ecosystem service responses to land use scenarios, incorporating adaptive valuation coefficients, can reveal actionable pathways to reconcile sustainable development and ecological conservation in mountainous regions. In this study, the ecosystem service value(ESV) dynamics in the Hunan–Jiangxi Border Region(HJBR), which is a representative old revolutionary base with a relatively undeveloped economy, were investigated by integrating historical land use data analysis from 2000 to 2020 and adopting patch-generating land use simulation(PLUS) modelling. Three policy-responsive scenarios, namely, natural growth(NGS), farmland protection(FPS), and ecological protection(EPS), were systematically developed to project ESV variations for 2030 and 2040. Our analysis revealed that from 2000 to 2020, urban sprawl and water body expansion occurred at the expense of forestland, cultivated land, and grassland, yet yield-driven productivity improvements increased the ESV by 227.30%(equivalent to ¥250.0 billion). By 2040, the NGS achieves the greatest ESV increase(¥189.895 billion) while fully accommodating urban land demand;the FPS yields the smallest ESV increase(¥148.169 billion), with the EPS occupying an intermediate position(¥182.207 billion). Climate regulation and hydrological services dominate ecological functions, collectively exceeding 49% across all the scenarios and periods. By 2040, most service functions exhibit growth trends except for a 0.30% water supply decline under the FPS, whereas the EPS demonstrates balanced development through multidimensional service enhancements. These findings underscore the necessity of integrating ecological safeguards into land use planning frameworks to ensure sustainable regional development. 展开更多
关键词 Ecosystem service value(ESV) Multiscenario simulation PLUS model LUCC Mountainous Regions Hunan–Jiangxi Border Region(HJBR)
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How does urbanization evolve heterogeneously in urbanized,urbanizing,and rural areas of China?Insights from ecosystem service value 被引量:2
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作者 Yikun Zhang Yongsheng Wang 《Geography and Sustainability》 2025年第3期117-128,共12页
The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to inv... The rapid population and land urbanization not only promoted economic development but also affected the ecosystem service value(ESV).In the context of new-type urbanization and green development,it’s essential to investigate the impacts of urbanization on ESV in China.However,a comprehensive and dynamic framework to reveal the relationship between ESV and urbanization processes is lacking.This study adopted multi-source datasets to portray China’s urbanization process by integrating population,land,and economic urbanization,eval-uated the ESV changes of 10 categories by gross ecosystem product(GEP)methods,and explored ESV changes within different urbanization scales and speeds.The results showed rapid urbanization in the population,land,and economic dimensions in China,with a faster process of economic urbanization.The ESV also exhibited an increasing trend,with higher levels in the southeastern coastal regions and lower levels in the northwestern regions.Urbanization had positive impacts on ESV across various research units,but the ESV exhibited heteroge-neous changes across different urbanization scales,speeds,and their interactive effects.The response of ESV to dynamic urbanization processes was influenced by socio-economic,ecological,and policy factors;it is essential to combine targeted measures with general ecological product value realization methods in each unit to maximize social-economic-ecological benefits. 展开更多
关键词 URBANIZATION Urban-rural areas Ecosystem service value Social-economic-ecological benefits China
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Dynamic changes and driving factors of ecosystem service value(ESV)in the Northeast Forest Belt of China 被引量:1
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作者 Jiao Shi Yujuan Gao Yuyou Zou 《Journal of Forestry Research》 2025年第2期167-186,共20页
The scientific assessment of ecosystem ser-vice value(ESV)plays a critical role in regional ecologi-cal protection and management,rational land use planning,and the establishment of ecological security barriers.The ec... The scientific assessment of ecosystem ser-vice value(ESV)plays a critical role in regional ecologi-cal protection and management,rational land use planning,and the establishment of ecological security barriers.The ecosystem service value of the Northeast Forest Belt from 2005 to 2020 was assessed,focusing on spatial–temporal changes and the driving forces behind these dynamics.Using multi-source data,the equivalent factor method,and geo-graphic detectors,we analyzed natural and socio-economic factors affecting the region.which was crucial for effective ecological conservation and land-use planning.Enhanced the effectiveness of policy formulation and land use plan-ning.The results show that the ESV of the Northeast Forest Belt exhibits an overall increasing trend from 2005 to 2020,with forests and wetlands contributing the most.However,there are significant differences between forest belts.Driven by natural and socio-economic factors,the ESV of forest belts in Heilongjiang and Jilin provinces showed significant growth.In contrast,the ESV of Forest Belts in Liaoning and Inner Mongolia of China remains relatively stable,but the spatial differentiation within these regions is characterized by significant clustering of high-value and low-value areas.Furthermore,climate regulation and hydrological regulation services were identified as the most important ecological functions in the Northeast Forest Belt,contributing greatly to regional ecological stability and human well-being.The ESV in the Northeast Forest Belt is improved during the study period,but the stability of the ecosystem is still chal-lenged by the dual impacts of natural and socio-economic factors.To further optimize regional land use planning and ecological protection policies,it is recommended to prior-itize the conservation of high-ESV areas,enhance ecological restoration efforts for wetlands and forests,and reasonably control the spatial layout of urban expansion and agricul-tural development.Additionally,this study highlights the importance of tailored ecological compensation policies and strategic land-use planning to balance environmental protec-tion and economic growth. 展开更多
关键词 Ecosystem service value(ESV) Northeast Forest Belt of China Equivalent factor method Geographic detectors Driving factors
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Quantifying the impacts of land use/land cover changes on ecosystem service values in the upper Gilgel Abbay watershed,Ethiopia 被引量:2
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作者 Wassie Abuhay ASCHENEFE Temesgen Gashaw TAREKEGN +1 位作者 Betelhem Fetene ADMAS Solomon Mulu TAFERE 《Regional Sustainability》 2025年第1期63-74,共12页
Human well-being and livelihoods depend on natural ecosystem services(ESs).Following the increment of population,ESs have been deteriorated over time.Ultimately,land use/land cover(LULC)changes have a profound impact ... Human well-being and livelihoods depend on natural ecosystem services(ESs).Following the increment of population,ESs have been deteriorated over time.Ultimately,land use/land cover(LULC)changes have a profound impact on the change of ecosystem.The primary goal of this study is to determine the impacts of LULC changes on ecosystem service values(ESVs)in the upper Gilgel Abbay watershed,Ethiopia.Changes in LULC types were studied using three Landsat images representing 1986,2003,and 2021.The Landsat images were classified using a supervised image classification technique in Earth Resources Data Analysis System(ERDAS)Imagine 2014.We classified ESs in this study into four categories(including provisioning,regulating,supporting,and cultural services)based on global ES classification scheme.The adjusted ESV coefficient benefit approach was employed to measure the impacts of LULC changes on ESVs.Five LULC types were identified in this study,including cultivated land,forest,shrubland,grassland,and water body.The result revealed that the area of cultivated land accounted for 64.50%,71.50%,and 61.50%of the total area in 1986,2003,and 2021,respectively.The percentage of the total area covered by forest was 9.50%,5.90%,and 14.80%in 1986,2003,and 2021,respectively.Result revealed that the total ESV decreased from 7.42×10^(7) to 6.44×10^(7) USD between 1986 and 2003.This is due to the expansion of cultivated land at the expense of forest and shrubland.However,the total ESV increased from 6.44×10^(7) to 7.76×10^(7) USD during 2003-2021,because of the increment of forest and shrubland.The expansion of cultivated land and the reductions of forest and shrubland reduced most individual ESs during 1986-2003.Nevertheless,the increase in forest and shrubland at the expense of cultivated land enhanced many ESs during 2003-2021.Therefore,the findings suggest that appropriate land use practices should be scaled-up to sustainably maintain ESs. 展开更多
关键词 Ecosystem service values(ESVs) Land use/land cover(LULC) Ecosystem services(ESs) Provisioning service Gilgel Abbay watershed
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Research on Optimizing the Index System of Value Assessment of Transportation Infrastructure Assets
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作者 Jie-ming Xia 《Proceedings of Business and Economic Studies》 2025年第4期202-207,共6页
This paper focuses on the optimization of the evaluation index system for the value of transportation infrastructure assets.It analyzes the shortcomings of the current system and explores the directions for optimizing... This paper focuses on the optimization of the evaluation index system for the value of transportation infrastructure assets.It analyzes the shortcomings of the current system and explores the directions for optimizing the index system from the perspectives of functionality,economy,social impact,environmental impact,and sustainability.The paper also discusses the application of the optimized index system in practical evaluation and the measures to ensure its effectiveness.The research aims to enhance the evaluation mechanism for the value of transportation infrastructure assets,providing a more scientific basis for decision-making,addressing challenges in asset management,improving the level of asset management in transportation infrastructure,and meeting the demands of high-quality development in the transportation sector in the new era. 展开更多
关键词 Transportation infrastructure Asset value evaluation Index system Optimization research
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Assessing the capacity value of demand flexibility from aggregated small Internet data centers in power distribution systems
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作者 Bo Zeng Xinzhu Xu Fulin Yang 《Global Energy Interconnection》 2025年第3期460-473,共14页
With the advent of the digital economy,there has been a rapid proliferation of small-scale Internet data centers(SIDCs).By leveraging their spatiotemporal load regulation potential through data workload balancing,aggr... With the advent of the digital economy,there has been a rapid proliferation of small-scale Internet data centers(SIDCs).By leveraging their spatiotemporal load regulation potential through data workload balancing,aggregated SIDCs have emerged as promising demand response(DR)resources for future power distribution systems.This paper presents an innovative framework for assessing capacity value(CV)by aggregating SIDCs participating in DR programs(SIDC-DR).Initially,we delineate the concept of CV tailored for aggregated SIDC scenarios and establish a metric for the assessment.Considering the effects of the data load dynamics,equipment constraints,and user behavior,we developed a sophisticated DR model for aggregated SIDCs using a data network aggregation method.Unlike existing studies,the proposed model captures the uncertainties associated with end tenant decisions to opt into an SIDC-DR program by utilizing a novel uncertainty modeling approach called Z-number formulation.This approach accounts for both the uncertainty in user participation intentions and the reliability of basic information during the DR process,enabling high-resolution profiling of the SIDC-DR potential in the CV evaluation.Simulation results from numerical studies conducted on a modified IEEE-33 node distribution system confirmed the effectiveness of the proposed approach and highlighted the potential benefits of SIDC-DR utilization in the efficient operation of future power systems. 展开更多
关键词 Aggregated Small internet data center Demand response Capacity value Z-number
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Spatial and Temporal Changes and Influencing Factors of Ecosystem Service Value in Jingzhou City Based on Land Use Change
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作者 GAO Yanpeng WANG Wanxi 《Journal of Landscape Research》 2025年第1期35-42,共8页
This study investigated the spatio-temporal variation characteristics of ecosystem service value(ESV)alongside its driving influencing factors,thereby offering valuable theoretical insights for the sustainable develop... This study investigated the spatio-temporal variation characteristics of ecosystem service value(ESV)alongside its driving influencing factors,thereby offering valuable theoretical insights for the sustainable development of Jingzhou City,Hubei Province.Based on the land use data for Jingzhou City from 2000 to 2020,this study quantified the value of the ecological environment using the equivalent factor method.Furthermore,it analyzed and elucidated the spatio-temporal heterogeneity and driving mechanisms of ecosystem services in Jingzhou City.The results indicated that between 2000 and 2020,cultivated land(66.40%)and water area(18.82%)were the predominant land use types in Jingzhou City.The areas of water area and construction land exhibited a growth trend during this period.Construction land had the highest rate of land use change,followed by water area and cultivated land.Land use transitions primarily occurred between cultivated land and water area,as well as between cultivated land and construction land.The total value of ecosystem services in Jingzhou City increased by 165.07%from 2000 to 2020.ESV exhibited an upward trend from 2000 to 2015,followed by a gradual decline from 2015 to 2020.The ranking of individual ecosystem services,in descending order,was as follows:regulation services,supporting services,provisioning services,and cultural services.High-value ESV areas were predominantly situated in the water area of Lake Honghu,while low-value regions were mainly found in the cultivated land in the central and western parts of Jingzhou City.The spatial differentiation of ESV in Jingzhzou City was influenced by both natural and socio-economic factors,with natural factors exerting a more significant impact than socioeconomic factors.Specifically,the Normalized Difference Vegetation Index(NDVI)was the dominant environmental factor,while GDP plays a synergistic role. 展开更多
关键词 Land use change Ecosystem service value Temporal and spatial variations Geographical detector Jingzhou City
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The Study of Long-Term Trading Revenue Distribution Models in Wind-Photovoltaic-Thermal Complementary Systems Based on the Improved Shapley Value Method
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作者 Dongfeng Yang Ruirui Zhang +1 位作者 Chuang Liu Guoiang Bian 《Energy Engineering》 2025年第7期2673-2694,共22页
Under the current long-term electricity market mechanism,new energy and thermal power face issues such as deviation assessment and compression of generation space.The profitability of market players is limited.Simulta... Under the current long-term electricity market mechanism,new energy and thermal power face issues such as deviation assessment and compression of generation space.The profitability of market players is limited.Simultaneously,the cooperation model among various energy sources will have a direct impact on the alliance’s revenue and the equity of income distribution within the alliance.Therefore,integrating new energy with thermal power units into an integrated multi-energy complementary system to participate in the long-term electricity market holds significant potential.To simulate and evaluate the benefits and internal distribution methods of a multi-energy complementary system participating in long-term market transactions,this paper first constructs a multi-energy complementary system integrated with new energy and thermal power generation units at the same connection point,and participates in the annual bilateral game as a unified market entity to obtain the revenue value under the annual bilateral market.Secondly,based on the entropy weight method,improvements are made to the traditional Shapley value distribution model,and an internal distribution model for multi-energy complementary systems with multiple participants is constructed.Finally,a Markov Decision Process(MDP)evaluation system is constructed for practical case verification.The research results show that the improved Shapley value distribution model achieves higher satisfaction,providing a reasonable allocation scheme for multi-energy complementary cooperation models. 展开更多
关键词 Multi-energy complementary system cooperative game enhancements to the Shapley value MDP indicators
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Impact of Land Use Change on Ecosystem Services Values in Danjiangkou Reservoir Area,China in the Context of National Water Network Project Construction
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作者 LIU Linghua ZHENG Liang +3 位作者 WANG Ying LIU Chongchong ZHANG Bowen BI Yuzhe 《Chinese Geographical Science》 2025年第1期111-130,共20页
Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the nationa... Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the national water network and guaranteeing regional ecological stability.Using the Danjiangkou Reservoir Area(DRA),China as the study area,this paper first examined the spatiotemporal dynamics of natural landscape patterns and ecosystem service values(ESV)in the DRA from 2000 to 2018 and then investigated the spatial clustering characteristics of the ESV using spatial statistical analysis tools.Finally,the patch-generating land use simulation(PLUS)model was used to simulate the natural landscape and future changes in the ESV of the DRA from 2018 to 2028 under four different development scenarios:business as usual(BAU),economic development(ED),ecological protection(EP),and shoreline protection(SP).The results show that:during 2000-2018,the construction of water facilities had a significant impact on regional land use/land cover(LULC)change,with a 24830 ha increase in watershed area.ESV exhibited an increasing trend,with a significant and growing spatial clustering effect.The transformation of farmland to water bodies led to accelerated ESV growth,while the transformation of forest land to farmland led to a decrease in the ESV.Normalized difference vegetation index(NDVI)had the strongest effect on the ESV.ESV exhibited a continuous increase from 2018 to 2028 under all the simulation scenarios.The EP scenario had the greatest increase in ESV,while the ED scenario had the smallest increase.The findings suggest that projected land use patterns under different scenarios have varied impacts on ecosystem services(ESs)and that the management and planning of the DRA should balance social,economic,ecological,and security benefits.nomic,ecological,and security benefits. 展开更多
关键词 ecosystem services value(ESV) national water network project of China South-to-North Water Diversion Project(SNWDP)of China multi-scenario simulation Danjiangkou Reservoir Area China
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A complex-valued Vandermonde precoding technique for VLC-OFDM systems
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作者 WANG Zhongpeng SHEN Wengyu +1 位作者 QIU Weiwei XUE Linlin 《Optoelectronics Letters》 2025年第9期541-546,共6页
High peak-to-average power ratio(PAPR)is the main disadvantage of visible light communication-based orthogonal frequency division multiplexing(VLC-OFDM)systems.To address this problem,a novel precoding method is propo... High peak-to-average power ratio(PAPR)is the main disadvantage of visible light communication-based orthogonal frequency division multiplexing(VLC-OFDM)systems.To address this problem,a novel precoding method is proposed in this paper.The complex-valued precoding matrix is constructed by a Vandermonde matrix.The researched results show the proposed precoding scheme has better PAPR performance when compared to the conventional real-valued precoding methods.Moreover,a general closed-form expression of bit error rate(BER)for Vandermonde precoded VLC-OFDM is derived for multipath fading channel.The obtained BER formula shows that Vandermonde precoding can improve the BER performance of VLC-OFDM system over multipath fading channel.This is verified by the simulation results.The researched results also show that different precoding schemes have the same BER performance but different PAPR performance. 展开更多
关键词 VLC OFDM BER Multipath fading complex valued precoding precoding method Vandermonde matrix orthogonal frequency division multiplexing vlc ofdm systemsto PAPR
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Nonlocal Boundary Value Problems for Nonlinear Fractional Differential Equations with a Disturbance Parameter on the Infinite Interval
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作者 ZHENG Yanping YANG Hui WANG Wenxia 《应用数学》 北大核心 2026年第2期360-372,共13页
This paper is concerned with a class of nonlinear fractional differential equations with a disturbance parameter in the integral boundary conditions on the infinite interval.By using Guo-Krasnoselskii fixed point theo... This paper is concerned with a class of nonlinear fractional differential equations with a disturbance parameter in the integral boundary conditions on the infinite interval.By using Guo-Krasnoselskii fixed point theorem,fixed point index theory and the analytic technique,we give the bifurcation point of the parameter which divides the range of parameter for the existence of at least two,one and no positive solutions for the problem.And,by using a fixed point theorem of generalized concave operator and cone theory,we establish the maximum parameter interval for the existence of the unique positive solution for the problem and show that such a positive solution continuously depends on the parameter.In the end,some examples are given to illustrate our main results. 展开更多
关键词 Boundary value problem Disturbance parameter Infinite interval Bifurcation point CONE
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Relationship between the extreme value distribution of bending moments and traffic characteristics for simply supported bridges based on WIM data
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作者 SUGIRA Jean Claude ZHOU Xiaoyi +3 位作者 LI Xiaoya LI Shutao RUAN Xin WANG Hao 《Journal of Southeast University(English Edition)》 2026年第1期65-73,共9页
Extreme traffic loads significantly challenge the safety and cost-effectiveness of highway bridges,especially under site-specific traffic conditions.Conventional assessments often rely on overly conservative load mode... Extreme traffic loads significantly challenge the safety and cost-effectiveness of highway bridges,especially under site-specific traffic conditions.Conventional assessments often rely on overly conservative load models,leading to excessive structural design.In this study,a framework for the prediction of maximum bending moments in simply supported bridges is developed by integrating weigh-in-motion(WIM)data,traffic microsimulation,and generalized extreme value(GEV)regression modeling to establish relationships between the GEV parameters(μ,σ,ξ)and traffic factors—heavy vehicle proportion,bridge span length,vehicle speed,headway,and traffic volume.Using one-year WIM data from 7.4 million vehicles,the developed models for μ and σ exhibit high predictive accuracy(R^(2)>0.95)and are validated through leave-one-out cross-validation.The prediction of ξ is less accurate(R^(2)≈0.6),requiring further improvement.Applying these models to a 1000-year return level yields a reliable,data-driven extrapolation,supporting optimized bridge design and safety assessment under varying traffic conditions. 展开更多
关键词 site-specific factors extreme value traffic load weigh-in-motion(WIM) generalized extreme value(GEV)parameters Monte Carlo simulation
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