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Spatiotemporal heterogeneity management:Optimizing the critical role of ecosystem services in achieving Sustainable Development Goals
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作者 Lingli Zuo Guohua Liu +3 位作者 Junyan Zhao Jiajia Li Shuyuan Zheng Xukun Su 《Geography and Sustainability》 2025年第1期95-104,共10页
Ecosystems play a pivotal role in advancing Sustainable Development Goals(SDGs)by providing indispensable and resilient ecosystem services(ESs).However,the limited analysis of spatiotemporal heterogeneity often re str... Ecosystems play a pivotal role in advancing Sustainable Development Goals(SDGs)by providing indispensable and resilient ecosystem services(ESs).However,the limited analysis of spatiotemporal heterogeneity often re stricts the recognition of ESs’roles in attaining SDGs and landscape planning.We selected 183 counties in the Sichuan Province as the study area and mapped 10 SDGs and 7 ESs from 2000 to 2020.We used correlation analysis,principal component analysis,Geographically and Temporally Weighted Regression model,and self organizing maps to reveal the spatiotemporal heterogeneity of the impacts of the bundle of ESs on the SDGs and to develop spatial planning and management strategies.The results showed that(1)SDGs were improved in all counties,with SDG 1(No Poverty)and SDG 3(Good Health and Well-being)exhibiting poor performance.West ern Sichuan demonstrated stronger performance in environment-related SDGs in the Sichuan Province,while the Sichuan Basin showed better progress in socio-economic-related SDGs;(2)habitat quality,carbon sequestration,air pollution removal,and soil retention significantly influenced the development of 9 SDGs;(3)supporting,regulating,and provisioning service bundles have persistent and stable spatiotemporal heterogeneity effects on SDG1,SDG8,SDG11,SDG13,and SDG15.These findings substantiate the need for integrated management of multiple ESs and facilitate the regional achievement of SDGs in geographically intricate areas. 展开更多
关键词 Sustainable Development Goal(SDG) Ecosystem service(es) Impact bundle Spatial planning Sichuan Province
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Relationship between the use of smart medical services and mental health status
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作者 Elif Sarac 《World Journal of Psychiatry》 SCIE 2025年第1期21-25,共5页
In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the ... In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the potential to positively influence mental health by providing monitoring,insights,and inter-ventions.However,they also come with challenges that need to be addressed.Understanding the primary purpose for which individuals use these smart tech-nologies is essential to tailoring them to specific mental health needs and prefe-rences. 展开更多
关键词 Smart devices Medical service USAGE PEOPLE RELATIONSHIP Mental health status
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Services Oriented Education,Shape Service Thinking for Software Engineering Students
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作者 Shijun Liu Lizhen Cui Li Pan 《计算机教育》 2025年第3期87-94,共8页
In recent years,service computing has been widely integrated into software development.Web service development,especially under the RESTful schema,needs to guide students in transferring from object-oriented to resour... In recent years,service computing has been widely integrated into software development.Web service development,especially under the RESTful schema,needs to guide students in transferring from object-oriented to resource-oriented architectural thinking and cultivating students’literacy in design thinking,design patterns,and development methods.This paper introduces the foundations of service thinking with a brief review of service sciences,the core features of service thinking,and how to train service thinking of students.It also introduces a case study in Shandong University in the construction of a service computing curriculum system,especially how to highlight the cultivation of service thinking in the design of service software system. 展开更多
关键词 services oriented education service thinking service computing
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Quantifying the impacts of land use/land cover changes on ecosystem service values in the upper Gilgel Abbay watershed,Ethiopia
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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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ISO/TS 9546 on third-party payment services released
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《China Standardization》 2025年第1期17-17,共1页
Third-party payment (TPP) is an evolving model of payment services provided by third-party payment service providers (TPPSPs) for every end user using a payment account in another entity. TPP plays an important role g... Third-party payment (TPP) is an evolving model of payment services provided by third-party payment service providers (TPPSPs) for every end user using a payment account in another entity. TPP plays an important role globally by complementing the offer of the traditional financial market players and contributes to the efficiency of payment transactions and financial systems. 展开更多
关键词 ISO/TS serviceS FINANCIAL
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Non-stationary response of complex ecosystem service networks to urbanization:Evidence from a typical eco-fragile area in China
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作者 Zhen Shen Yang Gao +3 位作者 Lei Wang Zheyi Xia Haowei Liu Ting Deng 《Geography and Sustainability》 2025年第1期170-184,共15页
Understanding the complex interactions between urbanization and ecosystem services(ESs)is crucial for optimiz ing planning policies and achieving sustainable urban management.While previous research has largely focuse... Understanding the complex interactions between urbanization and ecosystem services(ESs)is crucial for optimiz ing planning policies and achieving sustainable urban management.While previous research has largely focused on highly urbanized areas,little attention has been given to the phased effect of progressive urbanization on ES networks.This study proposes a conceptual framework that utilizes the network method and space-time replace ment to examine the effect of urbanization on the complex relationships among ESs at different stages,with a particular emphasis on the progressive evolution of the process.We apply this framework to the Horqin area,a typical eco-fragile area in China.Results demonstrate that the connectivity of the ES synergy network exhibits a non-stationary characteristic,initially increasing,then decreasing,and subsequently strengthening.Meanwhile,its modularity shows a rising trend during periods of accelerated urbanization.The performance of the trade off network displays the opposite pattern.Additionally,we observe a gradual replacement of provisioning and regulation services by cultural services in terms of dominance in the synergy network as urbanization advances.By providing guidance for identifying key planning initiatives and implementing ecological protection policies at different stages of development,this study contributes a pathway that can inform development strategies in other regions undergoing progressive urbanization. 展开更多
关键词 Ecosystem services URBANIZATION Network analysis Non-stationary fluctuation
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Extreme weather characteristics and influences on urban ecosystem services in Wuhan Urban Agglomeration
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作者 Xin Dai Lunche Wang +2 位作者 Jie Gong Zigeng Niu Qian Cao 《Geography and Sustainability》 2025年第1期211-222,共12页
In recent years,there has been a pronounced increase in the frequency of extreme weather events.To compre hensively examine the impact of extreme weather on ecosystem services within the Wuhan Urban Agglomera tion(WUA... In recent years,there has been a pronounced increase in the frequency of extreme weather events.To compre hensively examine the impact of extreme weather on ecosystem services within the Wuhan Urban Agglomera tion(WUA),this study utilized meteorological station data,the Mann-Kendall(MK)test,and the Standardized Precipitation-Evapotranspiration Index(SPEI)to quantify the variation trends in heatwaves(HW)and droughts from 1961 to 2020.Then the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model was employed to evaluate and compare the differences in water yield and climate regulation ecosystem services un der various HW,droughts,and HW-drought combination scenarios.The results show that over the past 60 years,the temperature,duration,and frequency of HW have significantly increased in the WUA.Specifically,the high est HW temperature,total HW days,HW frequency,and average HW temperature showed changing trend of+0.17℃/decade,+1.4 day/decade,+0.19 event/decade,and+0.07℃/decade,respectively.The year 2000 was identified as a mutation year for HW,characterized by increased frequency and heightened severity thereafter.The SPEI value exhibited an insignificant upward trend,with 1980 marked as a mutation year,indicating a de creasing trend in drought occurrences after 1980.Heatwaves have a weakening effect on both water yield and climate regulation services,while drought significantly weakened water yield and had a relatively modest effect on climate regulation.During HW-drought composite period,the average monthly water yield showed a notable discrepancy of 60 mm compared to humid years.Besides,as heatwaves intensify,the area of low aggregation for ecosystem services expands,whereas the area of high aggregation decreases.This study provides a preliminary understanding of the impact of urban extreme weather on urban ecosystem services under changing climatic conditions. 展开更多
关键词 Heatwaves DROUGHT Ecosystem services Extreme weather composite events
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Fengyun Radiation Services for Solar Energy Meteorology:Status and Perspective
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作者 Xiang’ao XIA Dazhi YANG Yanbo SHEN 《Advances in Atmospheric Sciences》 2025年第2期252-260,共9页
Satellite remote sensing is essential for solar energy meteorology.The 14-channel Advanced Geostationary Radiation Imager of the Fengyun-4 series of satellites performs a full-disc scan over greater China every 15 min... Satellite remote sensing is essential for solar energy meteorology.The 14-channel Advanced Geostationary Radiation Imager of the Fengyun-4 series of satellites performs a full-disc scan over greater China every 15 min,providing highgranularity information that allows the retrieval of cloud properties,aerosol optical depth,and precipitable water vapor content,which can facilitate the acquisition of surface solar irradiance components through physical methods.Machinelearning methods have also shown potential in providing accurate end-to-end surface solar radiation retrievals.Albeit the physical principles of irradiance retrieval and machine-learning algorithms are fairly well known,the public service concerning disseminating the irradiance product to the energy and power industry still lacks robustness and consistency.In this perspective article,the status quo of Fengyun-4 irradiance products is first reviewed.Then,from the perspective of solar resource assessment and forecasting,three fundamental characteristics of the kind of irradiance products that are most serviceable to the solar energy sector are identified,namely,coverage,timeliness,and accessibility.Finally,an outlook on the new-generation Fengyun radiation service is put forward,and the prospective scientific and practical challenges are elaborated. 展开更多
关键词 Fengyun satellite solar energy meteorology public service satellite-derived irradiance
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Coordinated Service Restoration of Integrated Power and Gas Systems with Renewable Energy Sources
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作者 Xincong Shi Yuze Ji +2 位作者 Xinrui Wang Ruimin Tian Chao Zhang 《Energy Engineering》 2025年第3期1199-1220,共22页
With the development of integrated power and gas distribution systems(IPGS)incorporating renewable energy sources(RESs),coordinating the restoration processes of the power distribution system(PS)and the gas distributi... With the development of integrated power and gas distribution systems(IPGS)incorporating renewable energy sources(RESs),coordinating the restoration processes of the power distribution system(PS)and the gas distribution system(GS)by utilizing the benefits of RESs enhances service restoration.In this context,this paper proposes a coordinated service restoration framework that considers the uncertainty in RESs and the bi-directional restoration interactions between the PS and GS.Additionally,a coordinated service restoration model is developed considering the two systems’interdependency and the GS’s dynamic characteristics.The objective is to maximize the system resilience index while adhering to operational,dynamic,restoration logic,and interdependency constraints.A method for managing uncertainties in RES output is employed,and convexification techniques are applied to address the nonlinear constraints arising from the physical laws of the IPGS,thereby reducing solution complexity.As a result,the service restoration optimization problem of the IPGS can be formulated as a computationally tractable mixed-integer second-order cone programming problem.The effectiveness and superiority of the proposed framework are demonstrated through numerical simulations conducted on the interdependent IEEE 13-bus PS and 9-node GS.The comparative results show that the proposed framework improves the system resilience index by at least 65.07%compared to traditional methods. 展开更多
关键词 service restoration renewable energy sources integrated energy systems extreme events convex optimization
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Research on Development Strategies for“Double First-Class”Construction of Subject Service in University Libraries
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作者 Haixin Liu Liping Liu Yanan Zhang 《Journal of Contemporary Educational Research》 2025年第1期25-31,共7页
This paper aims to explore the development strategies for subject services in university libraries within the context of the“double first-class”initiative.By examining the relationship between“double first-class”c... This paper aims to explore the development strategies for subject services in university libraries within the context of the“double first-class”initiative.By examining the relationship between“double first-class”construction and university library subject services,the study analyzes the current state of subject services,including resource development,service models,and team building.Drawing on domestic and international case studies,the paper proposes a series of targeted and practical strategies to enhance the quality of subject services in university libraries,thereby providing robust support for the advancement of the“double first-class”initiative. 展开更多
关键词 “Double first-class”construction University library Subject service Development strategy
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Ultra-Dense LEO Satellite-Aircraft Access and Service Management in Civil Aviation
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作者 Wang Yilei Ma Ting +3 位作者 Liu Xiaoyu Gao Zhuxuan Zhou Haibo Shen Xuemin 《China Communications》 2025年第1期277-292,共16页
With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have i... With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have increased dramatically,especially for providing airborne Internet services.However,due to dynamic service demands and onboard LEO resources over time and space,it poses huge challenges in satellite-aircraft access and service management in ultra-dense LEO satellite networks(UDLSN).In this paper,we propose a deep reinforcement learning-based approach for ultra-dense LEO satellite-aircraft access and service management.Firstly,we develop an airborne Internet architecture based on UDLSN and design a management mechanism including medium earth orbit satellites to guarantee lightweight management.Secondly,considering latency-sensitive and latency-tolerant services,we formulate the problem of satellite-aircraft access and service management for civil aviation to ensure service continuity.Finally,we propose a proximal policy optimization-based access and service management algorithm to solve the formulated problem.Simulation results demonstrate the convergence and effectiveness of the proposed algorithm with satisfying the service continuity when applying to the UDLSN. 展开更多
关键词 civil aviation deep reinforcement learning satellite-aircraft access service management ultra-dense LEO satellite network
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Multi-scenario simulation of land use change and its impact on ecosystem services in the northeastern edge of the Qinghai-Xizang Plateau,China
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作者 ZHANG Xuebin LIU Yanni +3 位作者 YIN Junfeng SHI Peiji FENG Haoyuan SHI Jing 《Journal of Arid Land》 2025年第2期145-166,共22页
The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity conservation.Gannan Tibetan Autonomous Prefecture(hereinafter ref... The Qinghai-Xizang Plateau(QXP)serves as a crucial ecological barrier in China and Asia,exerting profound influences on global climate and biodiversity conservation.Gannan Tibetan Autonomous Prefecture(hereinafter referred as Gannan Prefecture),located on the northeastern edge of the QXP,represents a fragile alpine ecosystem in which land use change significantly impacts ecosystem services(ESs).This study established a comprehensive framework,utilizing the Patch-generating Land-Use Simulation(PLUS)model coupled with the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model to predict land use patterns under the natural development scenario,cultivated land protection scenario,and ecological protection scenario for Gannan Prefecture by 2030 and evaluated four critical ESs:habitat quality(HQ),water yield(WY),soil retention(SR),and carbon storage(CS).The primary aim is to elucidate the impacts of dynamic land use change on ESs.The results revealed that,from 2000 to 2020,HQ exhibited minimal variation,whereas CS experienced a slight decline.Conversely,WY and SR showed significant improvements.Under the natural development scenario,construction land was projected to increase by 4247.74 hm^(2),primarily at the expense of forest land.The cultivated land protection scenario anticipated an increase in farmland by 2634.36 hm^(2),which was crucial for maintaining food security.The ecological protection scenario predicted a notable expansion of forest land,accompanied by a restrained development rate of construction land.The ecological protection scenario also showed an increase in the ecosystem service index(ESI),encompassing 26.07%of the region.Forest land and grassland emerged as the primary contributors to ESs,while construction land substantially impacted WY.Water bodies exhibited minimal contribution to ESs.This study enhanced the understanding of land use change impacts on ESs in fragile and high-altitude ecosystems,offering essential theoretical frameworks and practical direction for forthcoming ecological policy and regional planning endeavors. 展开更多
关键词 PLUS-InVesT model ecosystem service habitat quality water yield soil retention carbon storage Qinghai-Xizang Plateau
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Survey and Recommendations for Land Use of Agricultural Machinery Service Organization Facilities in Guizhou Province
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作者 Xingyuan QI Chunbo LIU +2 位作者 Zhifei JIN Yingfen WANG Shuyun LIN 《Asian Agricultural Research》 2025年第1期14-17,共4页
With the advancement of agricultural modernization, agricultural machinery service organizations, as an important part of the rural operating entities, show an increasing trend year by year, and need new facilities la... With the advancement of agricultural modernization, agricultural machinery service organizations, as an important part of the rural operating entities, show an increasing trend year by year, and need new facilities land in the process of development and growth. Based on the written survey of 597 agricultural machinery service organizations in Guizhou Province, the demand and demand gap of various facilities land use in agricultural machinery service organizations were analyzed and compared. In addition, based on the field survey and policy background, the main practices and experiences of agricultural machinery service organizations in Guizhou Province in the approval and use of facility land were sorted out, and the problems and causes of large gap in facility agricultural land, lack of standards and difficulty in policy implementation were analyzed. Finally, it recommended that the site selection of agricultural machinery service organization facilities needs to be standardized, the land demand needs to be coordinated, the land scale needs to be scientifically demonstrated, and financial support should be sought to promote Guizhou agricultural machinery service organization to become bigger, better and stronger. 展开更多
关键词 Agricultural machinery service organization Facility land use Current situation survey Agricultural mechanization Guizhou Province
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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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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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基于ESE法则四年级小学生课外体育锻炼质量研究——以兰州市某小学为例
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作者 柳颖 沈童飞 晏思旖 《四川体育科学》 2025年第1期140-145,共6页
小学生课外体育锻炼质量影响小学生身体素质。为了解我国小学生体育锻炼质量,从有效性(Effectiveness)、科学性(Scientificity)、积极性(Enthusiasm)三个维度及六个亚维度构建ESE法则,编制《小学生课外体育锻炼质量量表》,运用层次分析... 小学生课外体育锻炼质量影响小学生身体素质。为了解我国小学生体育锻炼质量,从有效性(Effectiveness)、科学性(Scientificity)、积极性(Enthusiasm)三个维度及六个亚维度构建ESE法则,编制《小学生课外体育锻炼质量量表》,运用层次分析法(AHP)构建“小学生课外体育锻炼质量评价体系”。以兰州市某小学四年级小学生为研究对象,通过问卷调查法、数学模型法、数理统计法对学生课外体育锻炼质量现状进行调查研究,发现小学生课外体育锻炼质量尚可,但体育锻炼设置的合理性有所欠缺,内在动机对学生课外体育积极性的影响较弱,并从体教融合、三方合作、提升内在动机、制定规划目标、开展体育竞赛、挖掘社区资源等方面,提出促进我国城市小学生课外体育锻炼质量提高的可行建议。 展开更多
关键词 esE法则 课外体育锻炼 质量 层次分析法(AHP)
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施药服务外包有助于农药减量施用吗?——来自CLES的经验证据
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作者 钱龙 饶清玲 陆华良 《华中农业大学学报(社会科学版)》 北大核心 2025年第2期103-115,共13页
有效减少农业生产中的农药施用对提升农产品品质和实现农业高质量发展至关重要。基于中国土地经济调查(CLES)2020年和2021年两年混合截面数据,探讨了施药环节服务外包对农药减量施用的影响及其作用机制。研究发现:第一,施药环节外包显... 有效减少农业生产中的农药施用对提升农产品品质和实现农业高质量发展至关重要。基于中国土地经济调查(CLES)2020年和2021年两年混合截面数据,探讨了施药环节服务外包对农药减量施用的影响及其作用机制。研究发现:第一,施药环节外包显著减少了农药施用。在调整样本组合、聚焦水稻种植户,处理选择性偏误和考虑内生性问题后,结论依然稳健。第二,机制检验表明,施药服务外包通过缓解劳动力约束和实现规模效应来减少农药施用,而农药类型替代这一路径没有得到验证。第三,情境性分析表明,前端环节外包程度强化了施药环节外包减少农药施用的促进效应,而上年度病虫害强度会弱化施药环节外包带来的农药减量效果。以上结论说明施药服务外包在减少农药施用中发挥着积极作用,需加快提升施药服务外包普及率,助力“双减”战略的实现。 展开更多
关键词 施药服务外包 社会化服务 农药减量 中国土地经济调查
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Residents’perceptions of ecosystem services in an urbanizing basin:A case study in the Guanting Reservoir basin,China 被引量:1
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作者 Yansong Bai Qingxu Huang +5 位作者 Luis Inostroza Haoran Xu Dan Yin Ziwen Liu Ling Zhang Fangjin Xu 《Geography and Sustainability》 CSCD 2024年第3期430-444,共15页
Understanding stakeholders’differences in perceptions of ecosystem services(ES)is crucial for guiding ecolog-ical conservation and planning.However,the variations of ES perception amongst different types of residents... Understanding stakeholders’differences in perceptions of ecosystem services(ES)is crucial for guiding ecolog-ical conservation and planning.However,the variations of ES perception amongst different types of residents in urbanizing areas along an urban-rural gradient are still poorly understood.Combining a questionnaire-based survey,redundancy analysis,and statistical tests,we delineated the urban-rural gradient according to local res-idents’socio-economic characteristics,and investigated the differences in local residents’perceptions of ES and potential factors affecting them in the Guanting Reservoir basin,a rapidly urbanizing basin in China.The results showed that residents living in urban-rural transitional areas attached great importance to provisioning services of providing food and domestic water,regulating services of carbon sequestration and air purification,and cul-tural services of providing education and training,which were 0.7%-13.1%,0.7%-9.1%and 2.5%-21.2%higher than that of residents in other areas,respectively.Age and occupation were major factors affecting residents’perceptions.In terms of land-use types that deliver ES,the difference in perceptions of ES delivered by grassland was the greatest amongst residents.Our results support recommendations for policymakers to take into account the stakeholders’diverse perceptions,thus promoting residents’sense of gain on ES. 展开更多
关键词 Ecosystem services STAKEHOLDER Urban-rural gradient URBANIZATION Urban sustainability
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Privacy-Preserving Healthcare and Medical Data Collaboration Service System Based on Blockchain and Federated Learning 被引量:1
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作者 Fang Hu Siyi Qiu +3 位作者 Xiaolian Yang ChaoleiWu Miguel Baptista Nunes Hui Chen 《Computers, Materials & Continua》 SCIE EI 2024年第8期2897-2915,共19页
As the volume of healthcare and medical data increases from diverse sources,real-world scenarios involving data sharing and collaboration have certain challenges,including the risk of privacy leakage,difficulty in dat... As the volume of healthcare and medical data increases from diverse sources,real-world scenarios involving data sharing and collaboration have certain challenges,including the risk of privacy leakage,difficulty in data fusion,low reliability of data storage,low effectiveness of data sharing,etc.To guarantee the service quality of data collaboration,this paper presents a privacy-preserving Healthcare and Medical Data Collaboration Service System combining Blockchain with Federated Learning,termed FL-HMChain.This system is composed of three layers:Data extraction and storage,data management,and data application.Focusing on healthcare and medical data,a healthcare and medical blockchain is constructed to realize data storage,transfer,processing,and access with security,real-time,reliability,and integrity.An improved master node selection consensus mechanism is presented to detect and prevent dishonest behavior,ensuring the overall reliability and trustworthiness of the collaborative model training process.Furthermore,healthcare and medical data collaboration services in real-world scenarios have been discussed and developed.To further validate the performance of FL-HMChain,a Convolutional Neural Network-based Federated Learning(FL-CNN-HMChain)model is investigated for medical image identification.This model achieves better performance compared to the baseline Convolutional Neural Network(CNN),having an average improvement of 4.7%on Area Under Curve(AUC)and 7%on Accuracy(ACC),respectively.Furthermore,the probability of privacy leakage can be effectively reduced by the blockchain-based parameter transfer mechanism in federated learning between local and global models. 展开更多
关键词 Blockchain technique federated learning healthcare and medical data collaboration service privacy preservation
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Design and pricing of maintenance service contract based on Nash non-cooperative game approach 被引量:1
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作者 SU Chun HUANG Kui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期118-129,共12页
Nowadays manufacturers are facing fierce challenge.Apart from the products,providing customers with multiple maintenance options in the service contract becomes more popular,since it can help to improve customer satis... Nowadays manufacturers are facing fierce challenge.Apart from the products,providing customers with multiple maintenance options in the service contract becomes more popular,since it can help to improve customer satisfaction,and ultimately promote sales and maximize profit for the manufacturer.By considering the combinations of corrective maintenance and preventive maintenance,totally three types of maintenance service contracts are designed.Moreover,attractive incentive and penalty mechanisms are adopted in the contracts.On this basis,Nash non-cooperative game is applied to analyze the revenue for both the manufacturer and customers,and so as to optimize the pricing mechanism of maintenance service contract and achieve a win-win situation.Numerical experiments are conducted.The results show that by taking into account the incentive and penalty mechanisms,the revenue can be improved for both the customers and manufacturer.Moreover,with the increase of repair rate and improvement factor in the preventive maintenance,the revenue will increase gradually for both the parties. 展开更多
关键词 maintenance service contract Nash game incentive and penalty mechanism corrective maintenance preventive maintenance
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