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Distribution,assessment,and sources of nutrients in river water in the headwaters of the Shule River Basin,Northeastern Qinghai-Tibet Plateau
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作者 Qin Yang Donghui Shangguan +2 位作者 Tianding Han Da Li Asim Qayyum Butt 《Journal of Environmental Sciences》 2026年第1期502-511,共10页
Nitrogen(N)and phosphorus(P)are essential nutrients and can significantly impact primary productivity of the ecosystem causing water environmental problems.However,their cycling mechanisms are not well understood in a... Nitrogen(N)and phosphorus(P)are essential nutrients and can significantly impact primary productivity of the ecosystem causing water environmental problems.However,their cycling mechanisms are not well understood in alpine mountains with climate change.Hence,94 samples of river water were collected from 2018 to 2020 in the headwaters of the Shule River Basin to assess the nutrients spatiotemporal distribution and combined ap-proach of water quality index to assess water quality and potential sources.The findings depict that high nutrient concentrations were found to coincide with snowmelt and glacial meltwater and rainfall recharge periods,while total flux peaked from June to September due to increased runoff.Notably,total nitrogen(TN)concentrations were significantly higher near the town,primarily attributed to the replenishment of nitrate(NO_(3)^(‒)-N)from live-stock manure.The high total P(TP)was near the glacier,which was attributed to the transportation of glacial sediments into the river,and pH was another critical factor.N was the primary nutrient limiting factor for the growth of phytoplankton in river water.Although the migration and transport of nutrients have altered with climate change,river water quality is good in alpine mountains based on an overall evaluation.These findings contribute to enriching nutrient datasets and highlight the importance of water resource management and water quality assessment in sensitive and fragile alpine mountains. 展开更多
关键词 NUTRIENTS Spatiotemporal distribution Water quality assessment Potential sources Alpine mountains
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World Journal of Gastroenterology Editorial Board
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《World Journal of Gastroenterology》 2026年第2期I0001-I0019,共19页
The World Journal of Gastroenterology Editorial Board Members are composed of 357 distinguished experts active in the relevant field,distributed in 46 countries/regions,including Italy(66),Japan(53),United States(31),... The World Journal of Gastroenterology Editorial Board Members are composed of 357 distinguished experts active in the relevant field,distributed in 46 countries/regions,including Italy(66),Japan(53),United States(31),China(29),South Korea(16),Spain(15),Australia(13),Greece(12),Brazil(11),Romania(8),Germany(7),India(7),Taiwan(7),United Kingdom(7),Türkiye(7),Hungary(5),Russia(5). 展开更多
关键词 world journal gastroenterology distinguished experts countries regions editorial board field distribution
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Optimal Dispatch of Urban Distribution Networks Considering Virtual Power Plant Coordination under Extreme Scenarios
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作者 Yong Li Yuxuan Chen +4 位作者 Jiahui He Guowei He Chenxi Dai Jingjing Tong Wenting Lei 《Energy Engineering》 2026年第1期204-220,共17页
Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the... Ensuring reliable power supply in urban distribution networks is a complex and critical task.To address the increased demand during extreme scenarios,this paper proposes an optimal dispatch strategy that considers the coordination with virtual power plants(VPPs).The proposed strategy improves systemflexibility and responsiveness by optimizing the power adjustment of flexible resources.In the proposed strategy,theGaussian Process Regression(GPR)is firstly employed to determine the adjustable range of aggregated power within the VPP,facilitating an assessment of its potential contribution to power supply support.Then,an optimal dispatch model based on a leader-follower game is developed to maximize the benefits of the VPP and flexible resources while guaranteeing the power balance at the same time.To solve the proposed optimal dispatch model efficiently,the constraints of the problem are reformulated and resolved using the Karush-Kuhn-Tucker(KKT)optimality conditions and linear programming duality theorem.The effectiveness of the strategy is illustrated through a detailed case study. 展开更多
关键词 Urban distribution network virtual power plant power supply support leader-follower optimization game extreme weather scenarios
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Towards Decentralized IoT Security: Optimized Detection of Zero-Day Multi-Class Cyber-Attacks Using Deep Federated Learning
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作者 Misbah Anwer Ghufran Ahmed +3 位作者 Maha Abdelhaq Raed Alsaqour Shahid Hussain Adnan Akhunzada 《Computers, Materials & Continua》 2026年第1期744-758,共15页
The exponential growth of the Internet of Things(IoT)has introduced significant security challenges,with zero-day attacks emerging as one of the most critical and challenging threats.Traditional Machine Learning(ML)an... The exponential growth of the Internet of Things(IoT)has introduced significant security challenges,with zero-day attacks emerging as one of the most critical and challenging threats.Traditional Machine Learning(ML)and Deep Learning(DL)techniques have demonstrated promising early detection capabilities.However,their effectiveness is limited when handling the vast volumes of IoT-generated data due to scalability constraints,high computational costs,and the costly time-intensive process of data labeling.To address these challenges,this study proposes a Federated Learning(FL)framework that leverages collaborative and hybrid supervised learning to enhance cyber threat detection in IoT networks.By employing Deep Neural Networks(DNNs)and decentralized model training,the approach reduces computational complexity while improving detection accuracy.The proposed model demonstrates robust performance,achieving accuracies of 94.34%,99.95%,and 87.94%on the publicly available kitsune,Bot-IoT,and UNSW-NB15 datasets,respectively.Furthermore,its ability to detect zero-day attacks is validated through evaluations on two additional benchmark datasets,TON-IoT and IoT-23,using a Deep Federated Learning(DFL)framework,underscoring the generalization and effectiveness of the model in heterogeneous and decentralized IoT environments.Experimental results demonstrate superior performance over existing methods,establishing the proposed framework as an efficient and scalable solution for IoT security. 展开更多
关键词 Cyber-attack intrusion detection system(IDS) deep federated learning(DFL) zero-day attack distributed denial of services(DDoS) MULTI-CLASS Internet of Things(IoT)
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基于深度学习算法的湿法冶金资源回收效率提升方法设计及研究 被引量:1
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作者 宋玉安 赵伟 《湿法冶金》 北大核心 2025年第1期125-131,共7页
为进一步提高湿法冶金资源回收率,解决资源回收流程控制的智能化、自动化控制程度不高的问题,提出了一种采用Transformer模型进行金属浸出率预测,再采用Distributional Q-function改进DQN模型进行湿法冶金金浸出率最大化的湿法冶金流程... 为进一步提高湿法冶金资源回收率,解决资源回收流程控制的智能化、自动化控制程度不高的问题,提出了一种采用Transformer模型进行金属浸出率预测,再采用Distributional Q-function改进DQN模型进行湿法冶金金浸出率最大化的湿法冶金流程控制方法。结果表明:该系统控制方法能有效提升湿法冶金过程中金属浸出率的预测准确率;基于Distributional Q-function改进DQN模型能有效降低资源回收率最大化模型的迭代计算时间。该法能有效提高某工厂湿法冶金资源回收率。 展开更多
关键词 Transformer模型 最优化 Distributional Q-function DQN模型 资源回收
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Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles 被引量:1
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作者 Yanting Liu Wei Huang +8 位作者 Jiayi Wen Xin Xiong Ting Xu Qi Wang Xiusheng Chen Xianxian Zhao Shihua Li Xiaojiang Li Weili Yang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1124-1134,共11页
The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin a... The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin are expressed in mammalian brains.This has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small animals.Understanding this issue is critical for elucidating the in vivo roles of PINK1 and Parkin.Recently,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate brain.In the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate brain.We found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey brains.PINK1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable distribution.Immunofluorescent double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial stress.These findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage. 展开更多
关键词 NEURODEGENERATION PARKIN Parkinson’s disease PINK1 subcellular distribution
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Coordinated Control Strategy of New Energy Power Generation System with Hybrid Energy Storage Unit 被引量:1
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作者 Yun Zhang Zifen Han +2 位作者 Biao Tian Ning Chen Yi Fan 《Energy Engineering》 EI 2025年第1期167-184,共18页
The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,... The new energy power generation is becoming increasingly important in the power system.Such as photovoltaic power generation has become a research hotspot,however,due to the characteristics of light radiation changes,photovoltaic power generation is unstable and random,resulting in a low utilization rate and directly affecting the stability of the power grid.To solve this problem,this paper proposes a coordinated control strategy for a newenergy power generation system with a hybrid energy storage unit based on the lithium iron phosphate-supercapacitor hybrid energy storage unit.Firstly,the variational mode decomposition algorithm is used to separate the high and low frequencies of the power signal,which is conducive to the rapid and accurate suppression of the power fluctuation of the energy storage system.Secondly,the fuzzy control algorithm is introduced to balance the power between energy storage.In this paper,the actual data is used for simulation,and the simulation results show that the strategy realizes the effective suppression of the bus voltage fluctuation and the accurate control of the internal state of the energy storage unit,effectively avoiding problems such as overshoot and over-discharge,and can significantly improve the stability of the photovoltaic power generation systemand the stability of the Direct Current bus.It is of great significance to promote the development of collaborative control technology for photovoltaic hybrid energy storage units. 展开更多
关键词 Photovoltaic power suppression hybrid energy storage unit variationalmodal decomposition fuzzy control power distribution control
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Data driven prediction of fragment velocity distribution under explosive loading conditions 被引量:4
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作者 Donghwan Noh Piemaan Fazily +4 位作者 Songwon Seo Jaekun Lee Seungjae Seo Hoon Huh Jeong Whan Yoon 《Defence Technology(防务技术)》 2025年第1期109-119,共11页
This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key de... This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key design parameters including casing dimensions and detonation positions.The paper details the finite element analysis for fragmentation,the characterizations of the dynamic hardening and fracture models,the generation of comprehensive datasets,and the training of the ANN model.The results show the influence of casing dimensions on fragment velocity distributions,with the tendencies indicating increased resultant velocity with reduced thickness,increased length and diameter.The model's predictive capability is demonstrated through the accurate predictions for both training and testing datasets,showing its potential for the real-time prediction of fragmentation performance. 展开更多
关键词 Data driven prediction Dynamic fracture model Dynamic hardening model FRAGMENTATION Fragment velocity distribution High strain rate Machine learning
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Revealing the intrinsic connection between residual strain distribution and dissolution mode in Mg-Sc-Y-Ag anode for Mg-air battery 被引量:2
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作者 Wei-li Cheng Xu-bang Hao +4 位作者 Jin-hui Wang Hui Yu Li-fei Wang Ze-qin Cui Cheng Chang 《Journal of Magnesium and Alloys》 2025年第3期1020-1033,共14页
The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconci... The dominated contradiction in optimizing the performance of magnesium-air battery anode lies in the difficulty of achieving a good balance between activation and passivation during discharge process.To further reconcile this contradiction,two Mg-0.1Sc-0.1Y-0.1Ag anodes with different residual strain distribution through extrusion with/without annealing are fabricated.The results indicate that annealing can significantly lessen the“pseudo-anode”regions,thereby changing the dissolution mode of the matrix and achieving an effective dissolution during discharge.Additionally,p-type semiconductor characteristic of discharge productfilm could suppress the self-corrosion reaction without reducing the polarization of anode.The magnesium-air battery utilizing annealed Mg-0.1Sc-0.1Y-0.1Ag as anode achieves a synergistic improvement in specific capacity(1388.89 mA h g^(-1))and energy density(1960.42 mW h g^(-1)).This anode modification method accelerates the advancement of high efficiency and long lifespan magnesium-air batteries,offering renewable and cost-effective energy solutions for electronics and emergency equipment. 展开更多
关键词 Mg-air batteries ANODE Residual strain distribution Dissolution mode Discharge mechanism
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Spatial differentiation of carbon emissions from energy consumption based on machine learning algorithm:A case study during 2015–2020 in Shaanxi,China 被引量:2
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作者 Hongye Cao Ling Han +1 位作者 Ming Liu Liangzhi Li 《Journal of Environmental Sciences》 2025年第3期358-373,共16页
Carbon emissions resulting from energy consumption have become a pressing issue for governments worldwide.Accurate estimation of carbon emissions using satellite remote sensing data has become a crucial research probl... Carbon emissions resulting from energy consumption have become a pressing issue for governments worldwide.Accurate estimation of carbon emissions using satellite remote sensing data has become a crucial research problem.Previous studies relied on statistical regression models that failed to capture the complex nonlinear relationships between carbon emissions and characteristic variables.In this study,we propose a machine learning algorithm for carbon emissions,a Bayesian optimized XGboost regression model,using multi-year energy carbon emission data and nighttime lights(NTL)remote sensing data from Shaanxi Province,China.Our results demonstrate that the XGboost algorithm outperforms linear regression and four other machine learning models,with an R^(2)of 0.906 and RMSE of 5.687.We observe an annual increase in carbon emissions,with high-emission counties primarily concentrated in northern and central Shaanxi Province,displaying a shift from discrete,sporadic points to contiguous,extended spatial distribution.Spatial autocorrelation clustering reveals predominantly high-high and low-low clustering patterns,with economically developed counties showing high-emission clustering and economically relatively backward counties displaying low-emission clustering.Our findings show that the use of NTL data and the XGboost algorithm can estimate and predict carbon emissionsmore accurately and provide a complementary reference for satellite remote sensing image data to serve carbon emission monitoring and assessment.This research provides an important theoretical basis for formulating practical carbon emission reduction policies and contributes to the development of techniques for accurate carbon emission estimation using remote sensing data. 展开更多
关键词 Machine learning Energy carbon emissions Nighttime light Spatial distribution
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Occurrence and potential risks of organophosphate esters in agricultural soils:A case study of Fuzhou City,Southeast China 被引量:2
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作者 Tao Wang Hong Zhang +6 位作者 Chong Huang Yujie Ben Hanlin Zhou Hangting Guo Yonghe Han Yong Zhang Ping Tong 《Journal of Environmental Sciences》 2025年第4期571-581,共11页
Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(... Fifty agricultural soil samples collected from Fuzhou,southeast China,were first investigated for the occurrence,distribution,and potential risks of twelve organophosphate esters(OPEs).The total concentration of OPEs(ΣOPEs)in soil ranged from 1.33 to 96.5 ng/g dry weight(dw),with an average value of 17.1 ng/g dw.Especially,halogenated-OPEs were the predominant group with amean level of 9.75 ng/g dw,and tris(1-chloro-2-propyl)phosphate(TCIPP)was the most abundant OPEs,accounting for 51.1%ofΣOPEs.The concentrations of TCIPP andΣOPEs were found to be significantly higher(P<0.05)in soils of urban areas than those in suburban areas.In addition,the use of agricultural plastic films and total organic carbon had a positive effect on the occurrence of OPE in this study.The positive matrix factorization model suggested complex sources of OPEs in agricultural soils from Fuzhou.The ecological risk assessment demonstrated that tricresyl phosphate presented a medium risk to land-based organisms(0.1≤risk quotient<1.0).Nevertheless,the carcinogenic and noncarcinogenic risks for human exposure to OPEs through soil ingestion and dermal absorption were negligible.These findings would facilitate further investigations into the pollution management and risk control of OPEs. 展开更多
关键词 Organophosphate esters(OPEs) Agricultural soils Spatial distribution Source identification Risk assessment
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Coupling and Spatial Disparities of Regional Economy and Ecosystem in High-Quality Town Development 被引量:2
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作者 Xinyi Ren Xiaowen Tan +2 位作者 Dan Luo Rongxin Lu Chien-Chi Chu 《Research in Ecology》 2025年第1期15-29,共15页
This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expan... This study investigates the coordination between regional economic growth and ecological sustainability within the context of high-quality town economy development.To address the challenges of balancing economic expansion with environmental protection,a comprehensive evaluation index system is constructed,encompassing two key dimensions:regional economy and ecological environment.Using panel data from 2013 to 2022,the coupling coordination degree model is employed to quantify the interactions and synergy between these dimensions.Additionally,spatial econometric methods are applied to calculate both global and local Moran’s Index,revealing spatial clustering patterns,regional disparities,and heterogeneity.The relative development model further identifies critical factors influencing regional coordination,with a focus on the lagging development of basic infrastructure and public services.The findings demonstrate a positive temporal trend toward improved regional coordination and reduced development gaps,with a spatial pattern characterized by higher coupling degrees in eastern and central regions compared to western areas.Based on these results,this study proposes actionable strategies to enhance coordinated development,emphasizing ecological conservation,the establishment of green production and consumption systems,ecological restoration,and strengthened municipal collaboration.This revised abstract emphasizes the study’s purpose,methods,and key findings more clearly while maintaining a professional and concise tone.Finally,based on the above analysis results,the corresponding coordinated development suggestions of regional economy and ecological environment are given from the aspects of ecological environment protection measures,green production and consumption system construction,ecological environment restoration and municipal coordination. 展开更多
关键词 Regional Economies Ecological Environment Coupling Coordination Degree Spatiotemporal Distribution Characteristics Relative Development Model
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Properties and structure investigation of the friction stir welding seam of the AA6061-T6 plates 被引量:2
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作者 M.Soukieh W.Harara +2 位作者 H.Koudaimi M.Halak M.Kassem 《China Welding》 2025年第2期132-138,共7页
Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW sea... Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW seams of AA6061-T6 plates were made us-ing different FSW parameters.The structure of the FSW seams was investigated using X-ray diffraction(XRD),scanning electron mi-croscope(SEM)and non destructive testing(NDT)techniques and their hardness was also measured.The dominated phase in the AA6061-T6 alloy and the FSW seams was theα-Al.The FSW seam had lower content of the secondary phases than the AA6061-T6 al-loy.The hardness of the FSW seams was decreased by about 30%compared to the AA6061-T6 alloy.The temperature distributions in the weld seams were also studied experimentally and numerically modeled and the results were in a good agreement. 展开更多
关键词 AA6061-T6 Friction stir welding welding parameters temperature distribution numerical modeling FSW weld seam
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Development of a coupled model to simulate and assess arsenic contamination and impact factors in the Jinsha River Basin,China 被引量:1
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作者 Yidian Sun Xu Zhang +5 位作者 Hong Peng Wenting Zhou Anna Jiang Feng Zhou Hao Wang Wanshun Zhang 《Journal of Environmental Sciences》 2025年第1期50-61,共12页
With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the pr... With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the precise control strategies.Taking the industrialintensive Jinsha River Basin as typical area,a two-dimensional hydrodynamic water quality model coupled with Soil andWater Assessment Tool(SWAT)model was developed to accurately simulate the watershed-scale distribution and transport of As in the terrestrial and aquatic environment at high spatial and temporal resolution.The effects of hydro-climate change,hydropower station construction and non-point source emissions on Aswere quantified based on the coupled model.The result indicated that higher As concentration areas mainly centralized in urban districts and concentration slowly decreased from upstream to downstream.Due to the enhanced rainfall,the As concentration was significantly higher during the rainy season than the dry season.Hydro-climate change and the construction of hydropower station not only affected the dissolved As concentration,but also affected the adsorption and desorption of As in sediment.Furthermore,As concentration increased with the input of non-point source pollution,with the maximum increase about 30%,resulting that non-point sources contributed important pollutant impacts to waterways.The coupled model used in pollutant behavior analysis is generalwith high potential application to predict and mitigate water pollution. 展开更多
关键词 Watershed system ARSENIC Modeling DISTRIBUTION Hydro-climate change Non-point source pollution
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A Trusted Distributed Oracle Scheme Based on Share Recovery Threshold Signature 被引量:1
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作者 Shihao Wang Xuehui Du +4 位作者 Xiangyu Wu Qiantao Yang Wenjuan Wang Yu Cao Aodi Liu 《Computers, Materials & Continua》 2025年第2期3355-3379,共25页
With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become ... With the increasing popularity of blockchain applications, the security of data sources on the blockchain is gradually receiving attention. Providing reliable data for the blockchain safely and efficiently has become a research hotspot, and the security of the oracle responsible for providing reliable data has attracted much attention. The most widely used centralized oracles in blockchain, such as Provable and Town Crier, all rely on a single oracle to obtain data, which suffers from a single point of failure and limits the large-scale development of blockchain. To this end, the distributed oracle scheme is put forward, but the existing distributed oracle schemes such as Chainlink and Augur generally have low execution efficiency and high communication overhead, which leads to their poor applicability. To solve the above problems, this paper proposes a trusted distributed oracle scheme based on a share recovery threshold signature. First, a data verification method of distributed oracles is designed based on threshold signature. By aggregating the signatures of oracles, data from different data sources can be mutually verified, leading to a more efficient data verification and aggregation process. Then, a credibility-based cluster head election algorithm is designed, which reduces the communication overhead by clarifying the function distribution and building a hierarchical structure. Considering the good performance of the BLS threshold signature in large-scale applications, this paper combines it with distributed oracle technology and proposes a BLS threshold signature algorithm that supports share recovery in distributed oracles. The share recovery mechanism enables the proposed scheme to solve the key loss issue, and the setting of the threshold value enables the proposed scheme to complete signature aggregation with only a threshold number of oracles, making the scheme more robust. Finally, experimental results indicate that, by using the threshold signature technology and the cluster head election algorithm, our scheme effectively improves the execution efficiency of oracles and solves the problem of a single point of failure, leading to higher scalability and robustness. 展开更多
关键词 Blockchain threshold signature distributed oracle data submission share recovery
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Seasonal variation in habitat preference of the Himalayan monal(Lophophorus impejanus)in Langtang National Park,Nepal:Implications for conservation 被引量:1
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作者 Birat Raj Rajak Laxman Khanal +4 位作者 Asmit Subba Amrit Nepali Sandip Kumar Gupta Hem Sagar Baral Randall C.Kyes 《Zoological Research(Diversity and Conservation)》 2025年第1期32-41,共10页
The Himalayan monal(Lophophorus impejanus),Nepal’s national bird,is a protected species facing significant conservation challenges.Understanding the distribution and habitat preferences of the Himalayan monal(HM)is c... The Himalayan monal(Lophophorus impejanus),Nepal’s national bird,is a protected species facing significant conservation challenges.Understanding the distribution and habitat preferences of the Himalayan monal(HM)is crucial for its conservation.This study was conducted in the Langtang National Park(LNP),Nepal using the route census method during both winter(November/December 2022)and summer(June 2023)seasons to examine the seasonal variation in HM’s elevational distribution and habitat preference.Further,we assessed their conservation threats by conducting a semi-structured questionnaire survey with the local residents.During the winter period,the HMs preferred grassland habitats,while in the summer,their preference shifted to shrubland and barren area.HM abundance was negatively associated with the Normalized Differential Vegetation Index(NDVI)and the shortest distance from the survey trails in the winter.The HMs actively avoided areas with high anthropogenic pressure.In the summer,they showed a wider elevational range up to 4400 m above sea level(a.s.l.),with a higher sighting frequency between 3600 and 3900 m a.s.l.The questionnaire survey of the local residents revealed that anthropogenic pressure such as poaching and free-ranging livestock grazing are the major threats to the species in the study area.This study provides valuable insight into the complex habitat preferences and critical threats faced by the HMs in LNP and underscores the urgent need for targeted conservation action. 展开更多
关键词 PHEASANTS National bird Conservation threats Seasonal habitats Elevational distribution
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Effects of micro-sprinkler irrigation and topsoil compaction on winter wheat grain yield and water use efficiency in the Huaibei Plain, China 被引量:1
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作者 Jinpeng Li Siqi Wang +6 位作者 Zhongwei Li Kaiyi Xing Xuefeng Tao Zhimin Wang Yinghua Zhang Chunsheng Yao Jincai Li 《Journal of Integrative Agriculture》 2025年第8期2974-2988,共15页
Increasing the grain yield(GY) and water use efficiency(WUE) of winter wheat in the Huaibei Plain(HP), China are essential. However, the effects of micro-sprinkler irrigation and topsoil compaction after wheat seed so... Increasing the grain yield(GY) and water use efficiency(WUE) of winter wheat in the Huaibei Plain(HP), China are essential. However, the effects of micro-sprinkler irrigation and topsoil compaction after wheat seed sowing on the GY and WUE are unclear. Therefore, a two-year field experiment was conducted during the 2021–2023 winter wheat growing seasons with a total six treatments: rain-fed(RF), conventional irrigation(CI) and micro-sprinkler irrigation(MI), as well as topsoil compaction after seed sowing under these three irrigation methods(RFC, CIC, and MIC). The results in the two years indicated that MI significantly increased GY compared to CI and RF, by averages of 17.9 and 42.1%, respectively. The increase in GY of MI was due to its significant increases in the number of spikes, kernels per spike, and grain weight. The chlorophyll concentration in flag leaves of MI after the anthesis stage maintained higher levels than with CI and RF, and was the lowest in RF. This was due to the dramatically enhanced catalase and peroxidase activities and lower malondialdehyde content under MI. Compared with RF and CI, MI significantly promoted dry matter remobilization and production after anthesis, as well as its contribution to GY. In addition, MI significantly boosted root growth, and root activity during the grain-filling stage was remarkably enhanced compared to CI and RF. In 2021–2022, there was no significant difference in WUE between MI and RF, but the WUE of RF was significantly lower than that of MI in 2022–2023. However, the WUE in MI was significantly improved compared to CI, and it increased by averages of 15.1 and 17.6% for the two years. Topsoil compaction significantly increased GY and WUE under rain-fed conditions due to improved spike numbers and dry matter production. Overall, topsoil compaction is advisable for enhancing GY and WUE in rain-fed conditions, whereas micro-sprinkler irrigation can be adopted to simultaneously achieve high GY and WUE in the HP. 展开更多
关键词 winter wheat MICRO-SPRINKLER grain yield root distribution water utilization
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Cement-mortar lining failure and metal release caused by electrochemical corrosion of ductile iron pipes in drinking water distribution systems 被引量:1
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作者 Hao Guo Rui Wang +5 位作者 Menghan Jiang Yimei Tian Yapeng Jin Weigao Zhao Chenwan Wang Jianhua Yin 《Journal of Environmental Sciences》 2025年第6期488-502,共15页
The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality d... The electrochemical corrosion of ductile pipes(DPs)in drinking water distribution systems(DWDS)has a crucial impact on cement-mortar lining(CML)failure and metal release,potentially leading to drinking water quality deterioration and posing a risk to public health.An in-situ scanning vibrating electrode technique(SVET)with micron-scale resolution,microscopic scale detection and water quality analysis were used to investigate the corrosion behavior and metal release from DPs throughout the whole CML failure process.Metal pollutants release occurred at three different stages of CML failure process,and there are potential risks of water quality deterioration exceeding the maximum allowable levels set by national standards in the partial failure stage and lining peeling stage.Furthermore,the effects of water chemistry(Cl^(−),SO_(4)^(2−),NO_(3)−,and Ca^(2+))on corrosion scale growth and iron release activity,were investigated during the CML partial failure stage.Results showed that the CML failure process in DPs was accelerated by the autocatalysis of localized corrosion.Cl^(−)was found to damage the uncorroded metal surface,while SO_(4)^(2−)mainly dissolved the corrosion scale surface,increasing iron release.Both the oxidation of NO_(3)−and selective sedimentation of Ca2+were found to enhance the stability of corrosion scales and inhibit iron release. 展开更多
关键词 Water distribution system Cement mortar lining Corrosion Metal release SVET
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Long-term spatiotemporal variations of ammonia in the Yangtze River Delta region of China and its driving factors 被引量:1
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作者 Jingkai Xue Chengzhi Xing +6 位作者 Qihua Li Shanshan Wang Qihou Hu Yizhi Zhu Ting Liu Chengxin Zhang Cheng Liu 《Journal of Environmental Sciences》 2025年第4期202-217,共16页
This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to 2020.Utilizing data fr... This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to 2020.Utilizing data from the Infrared Atmospheric Sounding Interfer-ometer(IASI),Generalized Additive Models(GAM),and the GEOS-Chem chemical transport model,we observed a significant increase of NH_(3)VCDs in the YRD between 2014 and 2020.The spatial distribution analysis revealed higher NH_(3)concentrations in the northern part of the YRD region,primarily due to lower precipitation,alkaline soil,and intensive agricul-tural activities.NH_(3)VCDs in the YRD region increased significantly(65.18%)from 2008 to 2020.The highest growth rate occurs in the summer,with an annual average growth rate of 7.2%during the period from 2014 to 2020.Agricultural emissions dominated NH_(3)VCDs during spring and summer,with high concentrations primarily located in the agricultural areas adjacent to densely populated urban zones.Regions within several large urban areas have been discovered to exhibit relatively stable variations in NH_(3)VCDs.The rise in NH_(3)VCDs within the YRD region was primarily driven by the reduction of acidic gases like SO_(2),as emphasized by GAM modeling and sensitivity tests using the GEOS-Chem model.The concentration changes of acidic gases contribute to over 80%of the interannual variations in NH_(3)VCDs.This emphasizes the crucial role of environmental policies targeting the reduction of these acidic gases.Effective emission control is urgent tomitigate environmental hazards and secondary particulate matter,especially in the northern YRD. 展开更多
关键词 Yangtze River Delta AMMONIA Spatiotemporal distribution Driving factors
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