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Impact of environmental taxes,hydroelectricity consumption,economic globalization,and gross domestic product(GDP)on the load capacity factor in the selected European Union(EU)member countries
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作者 Funda KAYA Badsha MIA +4 位作者 MostAsikha AKTAR Md.Shaddam HOSSAIN Md.Mahedi HASSAN Muhammad Abdur RAHAMAN Liton Chandra VOUMIK 《Regional Sustainability》 2025年第2期17-30,共14页
The intersection of economic development,energy dynamics,environmental policy,and environmental sustainability presents complex challenges for European Union(EU)countries.This study investigatedthe impact of environme... The intersection of economic development,energy dynamics,environmental policy,and environmental sustainability presents complex challenges for European Union(EU)countries.This study investigatedthe impact of environmental taxes,hydroelectricity consumption,economic globalization,and gross domestic product(GDP)on the load capacity factor(LCF)in the 10 EU member countries(including Austria,Finland,France,Germany,Italy,Poland,Portugal,Slovakia,Spain,and Sweden)using data from 1995 to 2020.To ensure the reliability and validity of the data,this study applied several advanced econometric tests,including the Pesaran and Yamagata slopeheterogeneitytest,Pesaran cross-sectional dependence(CSD)test,second-generation unit root test,and Westerlund cointegration test.The data showed important statistical issues such as slope heterogeneityacross panels,CSD,mixed-orderunit root structures,and long-run associations between variables.To address these issues,we applied an augmented mean group(AMG)model as the main regression approach,andusedthe pooled mean group-autoregressive distributed lag(PMG-ARDL)method to check the robustness.Specifically,the AMG results indicate that a 1.000%rise in hydroelectricity consumptionresults in a 0.048% rise in the LCF,while a 1.000% increase in environmental taxes leads toa 0.175% increase in the LCF.Contrary to this,a 1.000% increase in economic globalization results in a 0.370% decrease in the LCF,and a 1.000% increase in GDP leads toa 0.850% decrease in the LCF.Environmental taxes have a more beneficial impact on the environment,and GDP has the most detrimental effect.The findings provide empirical evidence on the role of environmental taxes,hydroelectricity consumption,economic globalization,and GDP in driving the LCF.Additionally,the findings provide valuable information to policy-makers,academicians,and stakeholders shaping energy and environmental policies in the 10 EU member countries. 展开更多
关键词 environmental taxes Hydroelectricity consumption Economic globalization Load capacity factor Sustainable development European Union(EU)member countries
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Recent Advancements in the Optimization Capacity Configuration and Coordination Operation Strategy of Wind-Solar Hybrid Storage System 被引量:1
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作者 Hongliang Hao Caifeng Wen +5 位作者 Feifei Xue Hao Qiu Ning Yang Yuwen Zhang Chaoyu Wang Edwin E.Nyakilla 《Energy Engineering》 EI 2025年第1期285-306,共22页
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe... Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems. 展开更多
关键词 Electric-thermal hybrid storage modal decomposition multi-objective genetic algorithm capacity optimization allocation operation strategy
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A NovelMethod for Determining Tourism Carrying Capacity in a Decision-Making Context Using q−Rung Orthopair Fuzzy Hypersoft Environment
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作者 Salma Khan Muhammad Gulistan +2 位作者 NasreenKausar Seifedine Kadry Jungeun Kim 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1951-1979,共29页
Tourism is a popular activity that allows individuals to escape their daily routines and explore new destinations for various reasons,including leisure,pleasure,or business.A recent study has proposed a unique mathema... Tourism is a popular activity that allows individuals to escape their daily routines and explore new destinations for various reasons,including leisure,pleasure,or business.A recent study has proposed a unique mathematical concept called a q−Rung orthopair fuzzy hypersoft set(q−ROFHS)to enhance the formal representation of human thought processes and evaluate tourism carrying capacity.This approach can capture the imprecision and ambiguity often present in human perception.With the advanced mathematical tools in this field,the study has also incorporated the Einstein aggregation operator and score function into the q−ROFHS values to supportmultiattribute decision-making algorithms.By implementing this technique,effective plans can be developed for social and economic development while avoiding detrimental effects such as overcrowding or environmental damage caused by tourism.A case study of selected tourism carrying capacity will demonstrate the proposed methodology. 展开更多
关键词 q−Rung orthopair fuzzy hypersoft set DECISION-MAKING tourism carrying capacity aggregation operator
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Quantitative Analysis of the Fatty Acid Compositions of Different Oils and Associations with Antioxidant Capacity and Oxidative Stability 被引量:1
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作者 LIU Junchen SUN Xiaoman +3 位作者 ZHANG Huirong SHAO Haofan LING Xiao LI Li 《现代食品科技》 北大核心 2025年第4期305-315,共11页
Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w... Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils. 展开更多
关键词 gas chromatography-mass spectrometry vegetable oil fatty acid composition oxidative stability antioxidant capacity
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Spatio-temporal evolution of the coordinated development of high-tech industry agglomeration and resource-environmental carrying capacity in the Yellow River Basin
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作者 LI Yan REN Ai-lian +1 位作者 LI Meng-yu SUN Fan 《Ecological Economy》 2024年第3期219-236,共18页
Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilizatio... Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilization construction.In light of the coupling coordination analysis of the coordination effect of provincial high-tech industry agglomeration and resource carrying capacity in the Yellow River Basin from 2009 to 2021,The evolution of the geographical and temporal pattern of development was investigated using the Moran index and kernel density estimation.The results show that the agglomeration of high-tech industries in the Yellow River Basin presents a development trend of seek improvement in stability,and there is a good coupling and coordination throughout the progression of scientific and technological innovation and the loading capacity of the resource,from the viewpoint of a time series.From the perspective of spatial pattern distribution,the whole basin aims at the lower reaches,accelerates the optimization of digital industry and promotes Yellow River Basin development of superior quality through innovation support and increase of input,and based on policy guidance. 展开更多
关键词 Yellow River Basin high-tech industrial agglomeration resource carrying capacity coupling coordination space-time evolution
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Dietary ferulic acid supplementation enhances antioxidant capacity and alleviates hepatocyte pyroptosis in diquat challenged piglets 被引量:1
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作者 Junqiu Luo Xiu Wu +2 位作者 Daiwen Chen Bing Yu Jun He 《Journal of Animal Science and Biotechnology》 2025年第1期377-387,共11页
Background Oxidative stress significantly impacts growth performance and liver function in piglets.Ferulic acid(FA)works as an antioxidant,however,the role and mechanism of FA in the regulation of diquat-induced oxida... Background Oxidative stress significantly impacts growth performance and liver function in piglets.Ferulic acid(FA)works as an antioxidant,however,the role and mechanism of FA in the regulation of diquat-induced oxidative stress in piglets are less known.This study was designed to investigate the effects of FA on growth performance and antioxi-dant capacity in piglets with diquat challenge.Methods Thirty-two healthy DLY(Duroc×Landrace×Yorkshire)piglets(13.24±0.19 kg)were randomly divided into one of two diets including 0 or 4 g/kg FA for 14 d.On d 15,all pigs were intraperitoneally injected diquat or sterile saline.Results Dietary supplementation with ferulic acid(FA)significantly improved the average daily gain(ADG)and decreased feed-gain ratio(F/G)of piglets.Here,dietary FA supplementation reduced serum aspartate aminotrans-ferase(AST),alanine aminotransferase(ALT)activities in diquat challenged piglets.Furthermore,diquat infusion increased reactive oxygen radicals(ROS)level in liver,decreased the activities of total superoxide dismutase(T-SOD)and glutathione peroxidase(GSH-Px),total antioxidant capacity(T-AOC)and increased malondialdehyde(MDA)con-tent in the liver and serum.Supplementation with FA significantly increased T-AOC and T-SOD activities and decreased MDA and ROS levels.FA down-regulated gene and protein expression of Keap1,and up-regulated protein expression of Nrf2 and HO-1 in the liver of piglets with diquat challenge.Importantly,diquat challenge increased the ratio of late apoptosis,increased serum levels of IL-1β,IL-18 and lactate dehydrogenase(LDH),and up-regulated pyroptosis-related genes in the liver.FA supplementation reduced the ratio of late apoptosis and down-regulated mRNA expression of Caspase-1.Accordingly,FA addition reduced concentration of IL-1β,IL-18,and LDH under diquat challenge.Conclusions Diquat-induced oxidative stress reduced growth performance and impaired liver function in piglets.Dietary FA supplementation enhanced the antioxidant capacity and reduced the degree of hepatocyte pyroptosis,thereby alleviating the oxidative damage in the liver and mitigating the impact of diquat on growth performance of piglets. 展开更多
关键词 Antioxidant capacity Ferulic acid Hepatic pyroptosis PIGLETS
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Optimal Production Capacity Matching for Blockchain-Enabled Manufacturing Collaboration With the Iterative Double Auction Method 被引量:1
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作者 Ying Chen Feilong Lin +2 位作者 Zhongyu Chen Changbing Tang Cailian Chen 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期550-562,共13页
The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a block... The increased demand for personalized customization calls for new production modes to enhance collaborations among a wide range of manufacturing practitioners who unnecessarily trust each other.In this article,a blockchain-enabled manufacturing collaboration framework is proposed,with a focus on the production capacity matching problem for blockchainbased peer-to-peer(P2P)collaboration.First,a digital model of production capacity description is built for trustworthy and transparent sharing over the blockchain.Second,an optimization problem is formulated for P2P production capacity matching with objectives to maximize both social welfare and individual benefits of all participants.Third,a feasible solution based on an iterative double auction mechanism is designed to determine the optimal price and quantity for production capacity matching with a lack of personal information.It facilitates automation of the matching process while protecting users'privacy via blockchainbased smart contracts.Finally,simulation results from the Hyperledger Fabric-based prototype show that the proposed approach increases social welfare by 1.4%compared to the Bayesian game-based approach,makes all participants profitable,and achieves 90%fairness of enterprises. 展开更多
关键词 Blockchain iterative double auction manufacturing collaboration production capacity matching
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Research progress on environmental behavior of arsenic in Qinghai-Tibet Plateau soil 被引量:1
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作者 Xitong Li Chuangchuang Zhang +5 位作者 Aofan Wang Tieliang Zhang Zeying He Yujie Zhao Wenjing Liu Qiwen Zhou 《Journal of Environmental Sciences》 2025年第7期237-250,共14页
The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to... The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau. 展开更多
关键词 Qinghai-Tibet Plateau SOIL ARSENIC Migration and transformation Ecological environment
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Rock Magnetic Evidence for the Seismogenic Environment of Large Earthquakes in the Motuo Fault Zone,Eastern Himalayan Syntaxis 被引量:1
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作者 CAO Yong SUN Zhiming +5 位作者 GAO Yang LIU Jian LI Bin YANG Yuhan YE Hao XU Peng 《Acta Geologica Sinica(English Edition)》 2025年第3期896-907,共12页
Knowledge of the seismogenic environment of fault zones is critical for understanding the processes and mechanisms of large earthquakes.We conducted a rock magnetic study of the fault rocks and protoliths to investiga... Knowledge of the seismogenic environment of fault zones is critical for understanding the processes and mechanisms of large earthquakes.We conducted a rock magnetic study of the fault rocks and protoliths to investigate the seismogenic environment of earthquakes in the Motuo fault zone,in the eastern Himalayan syntaxis.The results indicate that magnetite is the principal magnetic carrier in the fault rocks and protolith,while the protolith has a higher content of paramagnetic minerals than the fault rocks.The fault rocks are characterized by a high magnetic susceptibility relative to the protolith in the Motuo fault zone.This is likely due to the thermal alteration of paramagnetic minerals to magnetite caused by coseismic frictional heating with concomitant hydrothermal fluid circulation.The high magnetic susceptibility of the fault rocks and neoformed magnetite indicate that large earthquakes with frictional heating temperatures>500℃have occurred in the Motuo fault zone in the past,and that the fault maintained an oxidizing environment with weak fluid action during these earthquakes.Our results reveal the seismogenic environment of the Motuo fault zone,and they are potentially important for the evaluation of the regional stability in the eastern Himalayan syntaxis. 展开更多
关键词 rock magnetism frictional heating seismogenic environment Motuo fault zone eastern Himalayan syntaxis
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Obtaining Electromagnetic Properties of Multi-Type Media in Realistic Environments:State-of-the-Art and Prospects 被引量:1
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作者 Guo Lantu Guan Ke +5 位作者 Liu Ting He Danping Zhang Haixia Zhu Qiuming Lu Jun Zhang Minggao 《China Communications》 2025年第1期25-40,共16页
To meet the requirements of electromagnetic(EM)theory and applied physics,this study presents an overview of the state-of-the-art research on obtaining the EM properties of media and points out potential solutions tha... To meet the requirements of electromagnetic(EM)theory and applied physics,this study presents an overview of the state-of-the-art research on obtaining the EM properties of media and points out potential solutions that can break through the bottlenecks of current methods.Firstly,based on the survey of three mainstream approaches for acquiring EM properties of media,we identify the difficulties when implementing them in realistic environments.With a focus on addressing these problems and challenges,we propose a novel paradigm for obtaining the EM properties of multi-type media in realistic environments.Particularly,within this paradigm,we describe the implementation approach of the key technology,namely“multipath extraction using heterogeneous wave propagation data in multi-spectrum cases”.Finally,the latest measurement and simulation results show that the EM properties of multi-type media in realistic environments can be precisely and efficiently acquired by the methodology proposed in this study. 展开更多
关键词 electromagnetic properties of media multi-type media parameter inversion ray tracing realistic environment
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Coupling Coordination Development and Driving Factors of New Energy Vehicles and Ecological Environment in China 被引量:1
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作者 XU Zonghuang 《Wuhan University Journal of Natural Sciences》 2025年第1期79-90,共12页
Studying the coupling coordination development of new energy vehicles(NEVs)and the ecological environment in China is helpful in promoting the development of NEVs in the country and is of great significance in promoti... Studying the coupling coordination development of new energy vehicles(NEVs)and the ecological environment in China is helpful in promoting the development of NEVs in the country and is of great significance in promoting high-quality development of new energy in China.This paper constructs an evaluation index system for the development of NEVs and the ecological environment.It uses game theory combining weighting model,particle swarm optimized projection tracking evaluation model,coupling coordination degree model,and machine learning algorithms to calculate and analyze the level of coupling coordination development of NEVs and the ecological environment in China from 2010 to 2021,and identifies the driving factors.The research results show that:(i)From 2010 to 2021,the development index of NEVs in China has steadily increased from 0.085 to 0.634,while the ecological environment level index significantly rose from 0.170 to 0.884,reflecting the continuous development of China in both NEVs and the ecological environment.(ii)From 2010 to 2012,the two systems—new energy vehicle(NEV)development and the ecological environment—were in a period of imbalance and decline.From 2013 to 2016,they underwent a transition period,and from 2017 to 2021,they entered a period of coordinated development showing a trend of benign and continuous improvement.By 2021,they reached a good level of coordination.(iii)Indicators such as the number of patents granted for NEVs,water consumption per unit of GDP,and energy consumption per unit of GDP are the main driving factors affecting the coupling coordination development of NEVs and the ecological environment in China. 展开更多
关键词 new energy vehicles(NEVs) ecological environment coupling coordination development machine learning driving factors
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Experimental and Numerical Study of Bonding Capacity of Interface between Ultra-High Performance Concrete and Steel Tube 被引量:1
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作者 Ruikun Xu Jiu Li +1 位作者 Wenjie Li Wei Zhang 《Structural Durability & Health Monitoring》 2025年第2期285-305,共21页
This study investigates the bond performance at the interfacial region shared by Ultra-High Performance Concrete(UHPC)and steel tubes through push-out tests.This study examines how changes in steel fiber volumetric ra... This study investigates the bond performance at the interfacial region shared by Ultra-High Performance Concrete(UHPC)and steel tubes through push-out tests.This study examines how changes in steel fiber volumetric ratio and thickness of steel tube influence the bond strength characteristics.The results show that as the enhancement of the steel tube wall thickness,the ultimate bond strength at the interface improves significantly,whereas the initial bond strength exhibits only slight variations.The influence of steel fiber volumetric ratio presents a nonlinear trend,with initial bond strength decreasing at low fiber content and increasing significantly as fiber content rises.Additionally,finite element(FE)simulations were applied to replicate the experimental conditions,and the outcomes showed strong correlation with the experimental data,confirming the exactitude of the FE model in predicting the bond behavior at the UHPC-Steel interface.These findings provide valuable insights for optimizing the design of UHPC-Filled steel tubes in high-performance structure. 展开更多
关键词 Ultra-high performance concrete filled steel tube(UHPCFST) push-out test bonding capacity cohesive zone model
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Exploring the spatially and temporally varying impacts of built environment factors on rail transit ridership 被引量:1
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作者 HU Mingxing WANG Chunxin 《Journal of Southeast University(English Edition)》 2025年第2期235-243,共9页
This study examined the influence of the built environment surrounding rail stations on rail transit ridership and its spatiotemporal variations,aiming to enhance rail transit operational efficiency and inform station... This study examined the influence of the built environment surrounding rail stations on rail transit ridership and its spatiotemporal variations,aiming to enhance rail transit operational efficiency and inform station planning and development.Data from 159 metro stations in Nanjing,collected over a 14-d period,were analyzed to identify changes in weekday and weekend ridership patterns.The analysis included explanatory variables grouped into three categories:urban spatial variables,socioeconomic vari-ables,and transit service variables.A geographically and temporally weighted regression(GTWR)model was developed,and its performance was compared with that of ordinary least squares(OLS)and geographically weighted regression(GWR)models.The results demonstrated that the GTWR model outperformed others in analyzing the relationship between rail transit ridership and the built environment.In addition,the coefficients of explanatory variables showed significant variation across spatiotemporal dimensions,revealing distinct patterns.Notably,the influence of commuter flows led to more pronounced temporal heterogeneity in the coefficients observed on weekdays.These findings offer valuable insights for optimizing urban public transportation systems and advancing integrated urban rail development. 展开更多
关键词 built environment rail transit ridership spatio-temporal analysis geographically and temporally weighted regression(GTWR)
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Modeling and Capacity Configuration Optimization of CRH5 EMU On-Board Energy Storage System
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作者 Mingxing Tian Weiyuan Zhang Zhaoxu Su 《Energy Engineering》 EI 2025年第1期307-329,共23页
In the context of the“dual carbon”goals,to address issues such as high energy consumption,high costs,and low power quality in the rapid development of electrified railways,this study focused on the China Railways Hi... In the context of the“dual carbon”goals,to address issues such as high energy consumption,high costs,and low power quality in the rapid development of electrified railways,this study focused on the China Railways High-Speed 5 Electric Multiple Unit and proposed a mathematical model and capacity optimization method for an onboard energy storage system using lithium batteries and supercapacitors as storage media.Firstly,considering the electrical characteristics,weight,and volume of the storage media,a mathematical model of the energy storage system was established.Secondly,to tackle problems related to energy consumption and power quality,an energy management strategy was proposed that comprehensively considers peak shaving and valley filling and power quality by controlling the charge/discharge thresholds of the storage system.Thecapacity optimization adopted a bilevel programming model,with the series/parallel number of storage modules as variables,considering constraints imposed by the Direct Current to Direct Current converter,train load,and space.An improved Particle Swarm Optimization algorithm and linear programming solver were used to solve specific cases.The results show that the proposed onboard energy storage system can effectively achieve energy savings,reduce consumption,and improve power qualitywhile meeting the load and space limitations of the train. 展开更多
关键词 Electrified railway regenerative braking bi-level programming on-board energy storage power quality capacity configuration
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Mechanistic Investigation of Capacity Degradation in Lithium Iron Phosphate Batteries under Low Temperature Cycling Conditions
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作者 Jianwei Sun Shuqing Guo Shikai Li 《Energy Engineering》 2025年第9期3625-3646,共22页
Since lithium-ion batteries have been put into use,the recession of work cycle efficiency at low temperatures has received widespread attention.In this paper,we investigated the effect of low temperature(−5℃,0℃,5℃)... Since lithium-ion batteries have been put into use,the recession of work cycle efficiency at low temperatures has received widespread attention.In this paper,we investigated the effect of low temperature(−5℃,0℃,5℃)environments on the performance of lithium-ion batteries,which are well-known for their excellent discharge performance,cycle life,and safety.However,lithium-ion batteries exhibit significant capacity degradation at low temperatures,especially at 0℃,losing availability after only 10 cycles.Therefore,we conducted cycle degradation tests at 1C discharge and 100% charge-discharge conditions.In this paper,we analyzed the surface morphology,structure,and elemental composition of the positive and negative electrodes before and after the aging process by disassembling theminto half-cells and using three physical characterization techniques:scanning electronmicroscopy(SEM),energy dispersive spectroscopy(EDS),and X-ray diffraction(XRD).Our study identifies the temperature range for accelerated aging,which provides guidance for the optimal use of lithium-ion batteries in low temperature environments,thus contributing to the rational utilization and enhanced the performance of lithium-ion batteries at low temperatures. 展开更多
关键词 capacity degradation lithiumiron phosphate/graphite batteries lowtemperature environment physical characterization
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The molecular weight of carbon dots calculated from colligative properties and their application in estimating surface adsorption capacity
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作者 Ting Sun Xinzhi Liang +3 位作者 Minghao Pang Xia Xin Ning Feng Hongguang Li 《日用化学工业(中英文)》 北大核心 2025年第4期422-429,共8页
Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to... Since the discovery of carbon dots(CDs)in 2004,the unique photoluminescence phenomenon of CDs has attracted widespread attention.However,the molecular weight of CDs has not been adequately quantified at present,due to CDs are atomically imprecise and their molecular weight distribution is broad.In this paper,a series of Pluronic-modified CDs were prepared and the structure of the CDs was briefly analyzed.Subsequently,a molecular weight measurement method based on colligative properties was developed,and the correction coefficient in the algorithm was briefly analyzed.The calculated molecular weight was applied to the determination of surface adsorption capacity.This work provided a method for averaging the molecular weight of atomically imprecise particulate materials,which is expected to provide new opportunities in related fields. 展开更多
关键词 carbon dots molecular weight colligative properties surface adsorption capacity
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Research on the Construction of Intellectual Property System and Optimization of Business Environment in China
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作者 Zhang Xue Lyu Guofu 《科技与法律(中英文)》 2025年第1期125-137,共13页
With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an import... With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country. 展开更多
关键词 intellectual property business environment system construction economic development
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Portable Software Environment for Ultrahigh-Resolution ELM Development on GPUs
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作者 Dali Wang Peter Schwartz +5 位作者 Fengming Yuan Franklin Eaglebarge Danial Riccuito Peter Thornton Chris Layton Qinglei Cao 《Journal of Computer and Communications》 2025年第2期28-36,共9页
This paper presents our endeavors in developing the large-scale, ultra-high-resolution E3SM Land Model (uELM), specifically designed for exascale computers furnished with accelerators such as Nvidia GPUs. The uELM is ... This paper presents our endeavors in developing the large-scale, ultra-high-resolution E3SM Land Model (uELM), specifically designed for exascale computers furnished with accelerators such as Nvidia GPUs. The uELM is a sophisticated code that substantially relies on High-Performance Computing (HPC) environments, necessitating particular machine and software configurations. To facilitate community-based uELM developments employing GPUs, we have created a portable, standalone software environment preconfigured with uELM input datasets, simulation cases, and source code. This environment, utilizing Docker, encompasses all essential code, libraries, and system software for uELM development on GPUs. It also features a functional unit test framework and an offline model testbed for comprehensive numerical experiments. From a technical perspective, the paper discusses GPU-ready container generations, uELM code management, and input data distribution across computational platforms. Lastly, the paper demonstrates the use of environment for functional unit testing, end-to-end simulation on CPUs and GPUs, and collaborative code development. 展开更多
关键词 E3SM Land Model Ultrahigh-Resolution ELM Portable Software environment GPU-Ready environment
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Influence of ultrafine cement on cement-soil in peat soil environment of Dianchi Lake
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作者 CAO Jing SUN Huafeng +5 位作者 HUANG Siyang KONG Cheng LIU Fangyi LIU Fuhua TIAN Lin ZHU Weiming 《土木与环境工程学报(中英文)》 北大核心 2025年第2期1-12,共12页
Treatment of peat soil foundation in Yunnan surrounding Dianchi and Erhai Lakes poses complex problems for engineering projects.It is insufficient to rely on ordinary cement to reinforce peat soil.In order to make the... Treatment of peat soil foundation in Yunnan surrounding Dianchi and Erhai Lakes poses complex problems for engineering projects.It is insufficient to rely on ordinary cement to reinforce peat soil.In order to make the reinforcement reliable,this experiment mixed(ultrafine cement)UFC into ordinary cement to form a composite solidify agent.This study aimed to analyze the influence of UFC proportion on the strength of cement-soil in the peat soil environment.Unconfined compressive strength(UCS)and scanning electron microscope(SEM)tests were conducted on samples soaked for 28 and 90 days,respectively.The test results show that without considering the effects of Humic Acid(HA)and Fulvic Acid(FA),incorporating UFC can significantly improve the UCS of cement-soil.The rapid hydration of the fine particles generates a large number of cementitious products,improves the cohesion of the soil skeleton,and fills the pores.However,when the proportion of UFC increases,the aggregate structure formed by a larger quantity of fine particles reduces the hydration rate and degree of cement hydration,making the UCS growth rate of cement-soil insignificant.In the peat soil environment,HA significantly weakened the UCS of cement-soil in both physical and chemical aspects.However,UFC can mitigate the adverse effect of HA on cement-soil by its small particle size,high surface energy,and solid binding ability.In addition,FA has a positive effect on the UCS of cement-soil soaked for 28 days and 90 days.The UFC addition could promote the enhancement effect of FA on cement-soil UCS.SEM test results showed that cement hydration products increased significantly with the increase of UFC proportion,and cementation between hydration products and soil particles was enhanced.The size and connectivity of cement-soil pores were significantly reduced,thereby improving cement-soil structural integrity. 展开更多
关键词 peat soil environment ultrafine cement(UFC) cement-soil strength test MICROSTRUCTURE
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Fluid-based moderate collision avoidance for UAV formation in 3-D low-altitude environments 被引量:1
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作者 Menghua ZHANG Honglun WANG +5 位作者 Zhiyu LI Yanxiang WANG Xianglun ZHANG Qiang TANG Shichao MA Jianfa WU 《Chinese Journal of Aeronautics》 2025年第6期533-551,共19页
Aiming to address the Unmanned Aerial Vehicle(UAV) formation collision avoidance problem in Three-Dimensional(3-D) low-altitude environments where dense various obstacles exist, a fluid-based path planning framework n... Aiming to address the Unmanned Aerial Vehicle(UAV) formation collision avoidance problem in Three-Dimensional(3-D) low-altitude environments where dense various obstacles exist, a fluid-based path planning framework named the Formation Interfered Fluid Dynamical System(FIFDS) with Moderate Evasive Maneuver Strategy(MEMS) is proposed in this study.First, the UAV formation collision avoidance problem including quantifiable performance indexes is formulated. Second, inspired by the phenomenon of fluids continuously flowing while bypassing objects, the FIFDS for multiple UAVs is presented, which contains a Parallel Streamline Tracking(PST) method for formation keeping and the traditional IFDS for collision avoidance. Third, to rationally balance flight safety and collision avoidance cost, MEMS is proposed to generate moderate evasive maneuvers that match up with collision risks. Comprehensively containing the time and distance safety information, the 3-D dynamic collision regions are modeled for collision prediction. Then, the moderate evasive maneuver principle is refined, which provides criterions of the maneuver amplitude and direction. On this basis, an analytical parameter mapping mechanism is designed to online optimize IFDS parameters. Finally, the performance of the proposed method is validated by comparative simulation results and real flight experiments using fixed-wing UAVs. 展开更多
关键词 Unmanned aerial vehicle Formation collision avoidance:3-D low-altitude environments Interfered fluid dynamical system 3-D dynamic collision region
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