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Multi-source heterogeneous data access management framework and key technologies for electric power Internet of Things
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作者 Pengtian Guo Kai Xiao +1 位作者 Xiaohui Wang Daoxing Li 《Global Energy Interconnection》 EI CSCD 2024年第1期94-105,共12页
The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initiall... The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initially built a power IoT architecture comprising a perception,network,and platform application layer.However,owing to the structural complexity of the power system,the construction of the power IoT continues to face problems such as complex access management of massive heterogeneous equipment,diverse IoT protocol access methods,high concurrency of network communications,and weak data security protection.To address these issues,this study optimizes the existing architecture of the power IoT and designs an integrated management framework for the access of multi-source heterogeneous data in the power IoT,comprising cloud,pipe,edge,and terminal parts.It further reviews and analyzes the key technologies involved in the power IoT,such as the unified management of the physical model,high concurrent access,multi-protocol access,multi-source heterogeneous data storage management,and data security control,to provide a more flexible,efficient,secure,and easy-to-use solution for multi-source heterogeneous data access in the power IoT. 展开更多
关键词 Power Internet of Things Object model High concurrency access Zero trust mechanism multi-source heterogeneous data
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Runout prediction of potential landslides based on the multi-source data collaboration analysis on historical cases
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作者 Jun Sun Yu Zhuang Ai-guo Xing 《China Geology》 CAS CSCD 2024年第2期264-276,共13页
Long runout landslides involve a massive amount of energy and can be extremely hazardous owing to their long movement distance,high mobility and strong destructive power.Numerical methods have been widely used to pred... Long runout landslides involve a massive amount of energy and can be extremely hazardous owing to their long movement distance,high mobility and strong destructive power.Numerical methods have been widely used to predict the landslide runout but a fundamental problem remained is how to determine the reliable numerical parameters.This study proposes a framework to predict the runout of potential landslides through multi-source data collaboration and numerical analysis of historical landslide events.Specifically,for the historical landslide cases,the landslide-induced seismic signal,geophysical surveys,and possible in-situ drone/phone videos(multi-source data collaboration)can validate the numerical results in terms of landslide dynamics and deposit features and help calibrate the numerical(rheological)parameters.Subsequently,the calibrated numerical parameters can be used to numerically predict the runout of potential landslides in the region with a similar geological setting to the recorded events.Application of the runout prediction approach to the 2020 Jiashanying landslide in Guizhou,China gives reasonable results in comparison to the field observations.The numerical parameters are determined from the multi-source data collaboration analysis of a historical case in the region(2019 Shuicheng landslide).The proposed framework for landslide runout prediction can be of great utility for landslide risk assessment and disaster reduction in mountainous regions worldwide. 展开更多
关键词 Landslide runout prediction Drone survey multi-source data collaboration DAN3D numerical modeling Jianshanying landslide Guizhou Province Geological hazards survey engineering
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Threat Modeling and Application Research Based on Multi-Source Attack and Defense Knowledge
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作者 Shuqin Zhang Xinyu Su +2 位作者 Peiyu Shi Tianhui Du Yunfei Han 《Computers, Materials & Continua》 SCIE EI 2023年第10期349-377,共29页
Cyber Threat Intelligence(CTI)is a valuable resource for cybersecurity defense,but it also poses challenges due to its multi-source and heterogeneous nature.Security personnel may be unable to use CTI effectively to u... Cyber Threat Intelligence(CTI)is a valuable resource for cybersecurity defense,but it also poses challenges due to its multi-source and heterogeneous nature.Security personnel may be unable to use CTI effectively to understand the condition and trend of a cyberattack and respond promptly.To address these challenges,we propose a novel approach that consists of three steps.First,we construct the attack and defense analysis of the cybersecurity ontology(ADACO)model by integrating multiple cybersecurity databases.Second,we develop the threat evolution prediction algorithm(TEPA),which can automatically detect threats at device nodes,correlate and map multisource threat information,and dynamically infer the threat evolution process.TEPA leverages knowledge graphs to represent comprehensive threat scenarios and achieves better performance in simulated experiments by combining structural and textual features of entities.Third,we design the intelligent defense decision algorithm(IDDA),which can provide intelligent recommendations for security personnel regarding the most suitable defense techniques.IDDA outperforms the baseline methods in the comparative experiment. 展开更多
关键词 multi-source data fusion threat modeling threat propagation path knowledge graph intelligent defense decision-making
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Forecasting China’s natural gas consumption based on a combination model 被引量:10
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作者 Gang Xu Weiguo W ang 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第5期493-496,共4页
Ensuring a sufficient energy supply is essential to a country. Natural gas constitutes a vital part in energy supply and therefore forecasting natural gas consumption reliably and accurately is an essential part of a ... Ensuring a sufficient energy supply is essential to a country. Natural gas constitutes a vital part in energy supply and therefore forecasting natural gas consumption reliably and accurately is an essential part of a country's energy policy. Over the years, studies have shown that a combinative model gives better projected results compared to a single model. In this study, we used Polynomial Curve and Moving Average Combination Projection (PCMACP) model to estimate the future natural gas consumption in China from 2009 to 2015. The new proposed PCMACP model shows more reliable and accurate results: its Mean Absolute Percentage Error (MAPE) is less than those of any previous models within the investigated range. According to the PCMACP model, the average annual growth rate will increase for the next 7 years and the amount of natural gas consumption will reach 171600 million cubic meters in 2015 in China. 展开更多
关键词 natural gas consumption forecasting combination model
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A new spatial coherence model and analytical coeffi cients for multi-support response spectrum combination 被引量:3
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作者 王君杰 陈虎 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第3期225-235,共11页
In this paper, a new spatial coherence model of seismic ground motions is proposed by a fitting procedure. The analytical expressions of modal combination (correlation) coefficients of structural response are develo... In this paper, a new spatial coherence model of seismic ground motions is proposed by a fitting procedure. The analytical expressions of modal combination (correlation) coefficients of structural response are developed for multi-support seismic excitations. The coefficients from both the numerical integration and analytical solutions are compared to verify the accuracy of the solutions. It is shown that the analytical expressions of numerical modal combination coefficients are of high accuracy. The results of random responses of an example bridge show that the analytical modal combination coefficients developed in this paper are accurate enough to meet the requirements needed in practice. In addition, the computational efficiency of the analytical solutions of the modal combination coefficients is demonstrated by the response computation of the example bridge. It is found that the time required for the structural response analysis by using the analytical modal combination coefficients is less than 1/20 of that using numerical integral methods. 展开更多
关键词 multi-support seismic excitations spatial coherence model modal combination coefficients computational efficiency power spectrum density
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Settlement Prediction of Dredger Fill with the Optimal Combination Model 被引量:2
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作者 王清 闫欢 +2 位作者 苑晓青 牛岑岑 张旭东 《Journal of Donghua University(English Edition)》 EI CAS 2014年第6期812-816,共5页
Post-construction settlement has gained increasing attention because it frequently causes engineering problems. A combined model is a commonly used prediction model that overcomes the difficulty of a single model( i. ... Post-construction settlement has gained increasing attention because it frequently causes engineering problems. A combined model is a commonly used prediction model that overcomes the difficulty of a single model( i. e., cannot reflect various regulations of settlement at some stages or the entire process). In this study,the correlation coefficient,maximum error values,and other values were obtained according to the fitting and predicted results of a single model. The coefficient of variation was then introduced to determine the weight of each model forming the combination. The proposed model was used to fit and predict for settlement and overcome the issue of utilizing a single model while determining the weight. The fitting predictive effect was also analyzed using the settlement fitting precision results. The fitting precision of optimizing the combination model is high. The predicted data of the post-construction settlement are closer to the calculated value of the settlement monitoring data. Moreover,the proposed model has good practicability,does not require the interval data of settlement,and restricts the model number. Thus,this model can be applied in the engineering field. 展开更多
关键词 dredger fill settlement prediction combination model coefficient of variation WEIGHT
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Multi-source information fused generative adversarial network model and data assimilation based history matching for reservoir with complex geologies 被引量:2
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作者 Kai Zhang Hai-Qun Yu +7 位作者 Xiao-Peng Ma Jin-Ding Zhang Jian Wang Chuan-Jin Yao Yong-Fei Yang Hai Sun Jun Yao Jian Wang 《Petroleum Science》 SCIE CAS CSCD 2022年第2期707-719,共13页
For reservoirs with complex non-Gaussian geological characteristics,such as carbonate reservoirs or reservoirs with sedimentary facies distribution,it is difficult to implement history matching directly,especially for... For reservoirs with complex non-Gaussian geological characteristics,such as carbonate reservoirs or reservoirs with sedimentary facies distribution,it is difficult to implement history matching directly,especially for the ensemble-based data assimilation methods.In this paper,we propose a multi-source information fused generative adversarial network(MSIGAN)model,which is used for parameterization of the complex geologies.In MSIGAN,various information such as facies distribution,microseismic,and inter-well connectivity,can be integrated to learn the geological features.And two major generative models in deep learning,variational autoencoder(VAE)and generative adversarial network(GAN)are combined in our model.Then the proposed MSIGAN model is integrated into the ensemble smoother with multiple data assimilation(ESMDA)method to conduct history matching.We tested the proposed method on two reservoir models with fluvial facies.The experimental results show that the proposed MSIGAN model can effectively learn the complex geological features,which can promote the accuracy of history matching. 展开更多
关键词 multi-source information Automatic history matching Deep learning Data assimilation Generative model
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Explicit Correlation Model of Multi-source Constraints for Re-design Parts with Complex Curved Surface 被引量:2
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作者 JIA Zhenyuan WANG Fuji +1 位作者 WANG Yongqing GUO Dongming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第2期385-391,共7页
In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related ... In precision machining of complex curved surface parts with high performance, geometry accuracy is not the only constraint, but the performance should also be met. Performance of this kind of parts is closely related to the geometrical and physical parameters, so the final actual size and shape are affected by multiple source constraints, such as geometry, physics, and performance. These parts are rather difficult to be manufactured and new manufacturing method according to performance requirement is urgently needed. Based on performance and manufacturing requirements for complex curved surface parts, a new classification method is proposed, which divided the complex curved surface parts into two categories: surface re-design complex curved surface parts with multi-source constraints(PRCS) and surface unique complex curved surface parts with pure geometric constraints(PUCS). A correlation model is constructed between the performance and multi-source constraints for PRCS, which reveals the correlation between the performance and multi-source constraints. A re-design method is also developed. Through solving the correlation model of the typical paws performance-associated surface, the mapping relation between the performance-associated surface and the related removal amount is obtained. The explicit correlation model and the method for the corresponding related removal amount of the performance-associated surface are built based on the classification of surface re-design complex curved surface parts with multi-source constraints. Research results have been used in the actual processing of the typical parts such as radome, common bottom components, nozzle, et al., which shows improved efficiency and accuracy of the precision machining for the surface re-design parts with complex curved surface. 展开更多
关键词 multi-source constraints surface re-design performance associated surface explicit correlation model
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AModel for the Optimization of the Shale Gas HorizontalWell Section Based on the Combination of Different Weighting Methods in the Frame of the Game Theory 被引量:3
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作者 Minxuan Li Jing Sun +5 位作者 Dehua Liu Yang Li Kuidong Li Wei Liu Jialin Xiao Jiani Hu 《Fluid Dynamics & Materials Processing》 EI 2020年第5期993-1005,共13页
Existing“evaluation indicators”are selected and combined to build a model to support the optimization of shale gas horizontal wells.Towards this end,different“weighting methods”,including AHP and the so-called ent... Existing“evaluation indicators”are selected and combined to build a model to support the optimization of shale gas horizontal wells.Towards this end,different“weighting methods”,including AHP and the so-called entropy method,are combined in the frame of the game theory.Using a relevant test case for the implementation of the model,it is shown that the horizontal section of the considered well is in the middle sweet spot area with good physical properties and fracturing ability.In comparison with the FSI(flow scanner Image)gas production profile,the new model seems to display better abilities for the optimization of horizontal wells. 展开更多
关键词 combination weight well section sweet spot AHP entropy method evaluation model
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3D Geological Modeling with Multi-source Data Integration in Polymetallic Region:A Case Study of Luanchuan,Henan Province,China 被引量:1
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作者 Gongwen Wang~(1,2),Shouting Zhang~(1,2),Changhai Yan~3,Yaowu Song~3,Limei Wang~1 1.School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 2.State Key laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Beijing 100083,China 3.Henan Institute of Geological Survey,Zhengzhou 450007,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期166-167,共2页
The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luan... The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole data.Luanchuan,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in China. 展开更多
关键词 3D GEOLOGICAL modeling multi-source data MINERAL exploration METALLOGENIC model virtual GEOLOGICAL section Luanchuan POLYMETALLIC REGION
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N-acetylcysteine and glycyrrhizin combination:Benefit outcome in a murine model of acetaminophen-induced liver failure 被引量:4
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作者 Charlotte Minsart Sandrine Rorive +2 位作者 Arnaud Lemmers Eric Quertinmont Thierry Gustot 《World Journal of Hepatology》 CAS 2020年第9期596-618,共23页
BACKGROUND Acetaminophen overdose is the most frequent cause of drug-induced liver failure in developed countries.Substantial progress has been made in understanding the mechanism of hepatocellular injury,but N-acetyl... BACKGROUND Acetaminophen overdose is the most frequent cause of drug-induced liver failure in developed countries.Substantial progress has been made in understanding the mechanism of hepatocellular injury,but N-acetylcysteine remains the only effective treatment despite its short therapeutic window.Thus,other hepatoprotective drugs are needed for the delayed treatment of acetaminopheninduced hepatotoxicity.Our interest focused on glycyrrhizin for its role as an inhibitor of high mobility group box 1(HMGB1)protein,a member of the family of damage-associated molecular pattern,known to play an important pathological role in various diseases.AIM To investigate the efficacy of the N-acetylcysteine/glycyrrhizin combination compared to N-acetylcysteine alone in the prevention of liver toxicity.METHODS Eight-week-old C57BL/6J wild-type female mice were used for all our experiments.Mice fasted for 15 h were treated with acetaminophen(500 mg/kg)or vehicle(phosphate-buffered saline)by intraperitoneal injection and separated into the following groups:Glycyrrhizin(200 mg/kg);N-acetylcysteine(150 mg/kg);and N-acetylcysteine/glycyrrhizin.In all groups,mice were sacrificed 12 h following acetaminophen administration.The assessment of hepatotoxicity was performed by measuring plasma levels of alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase.Hepatotoxicity was also evaluated by histological examination of hematoxylin and eosin-stained tissues sections.Survival rates were compared between various groups using Kaplan-Meier curves.RESULTS Consistent with data published in the literature,we confirmed that intraperitoneal administration of acetaminophen(500 mg/kg)in mice induced severe liver injury as evidenced by increases in alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase but also by liver necrosis score.Glycyrrhizin administration was shown to reduce the release of HMGB1 and significantly decreased the severity of liver injury.Thus,the co-administration of glycyrrhizin and N-acetylcysteine was investigated.Administered concomitantly with acetaminophen,the combination significantly reduced the severity of liver injury.Delayed administration of the combination of drugs,2 h or 6 h after acetaminophen,also induced a significant decrease in hepatocyte necrosis compared to mice treated with N-acetylcysteine alone.In addition,administration of N-acetylcysteine/glycyrrhizin combination was associated with an improved survival rate compared to mice treated with only N-acetylcysteine.CONCLUSION We demonstrate that,compared to N-acetylcysteine alone,co-administration of glycyrrhizin decreases the liver necrosis score and improves survival in a murine model of acetaminophen-induced liver injury.Our study opens a potential new therapeutic pathway in the prevention of acetaminophen hepatotoxicity. 展开更多
关键词 ACETAMINOPHEN Acute liver injury GLYCYRRHIZIN N-ACETYLCYSTEINE Nacetylcysteine/glycyrrhizin combination Murine model High mobility group box 1
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Combined hybrid energy storage system and transmission grid model for peak shaving based on time series operation simulation
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作者 Mingkui Wei Yiyu Wen +3 位作者 Qiu Meng Shunwei Zheng Yuyang Luo Kai Liao 《Global Energy Interconnection》 EI CAS CSCD 2023年第2期154-165,共12页
This study proposes a combined hybrid energy storage system(HESS) and transmission grid(TG) model, and a corresponding time series operation simulation(TSOS) model is established to relieve the peak-shaving pressure o... This study proposes a combined hybrid energy storage system(HESS) and transmission grid(TG) model, and a corresponding time series operation simulation(TSOS) model is established to relieve the peak-shaving pressure of power systems under the integration of renewable energy. First, a linear model for the optimal operation of the HESS is established, which considers the different power-efficiency characteristics of the pumped storage system, electrochemical storage system, and a new type of liquid compressed air energy storage. Second, a TSOS simulation model for peak shaving is built to maximize the power entering the grid from the wind farms and HESS. Based on the proposed model, this study considers the transmission capacity of a TG. By adding the power-flow constraints of the TG, a TSOS-based HESS and TG combination model for peak shaving is established. Finally, the improved IEEE-39 and IEEE-118 bus systems were considered as examples to verify the effectiveness and feasibility of the proposed model. 展开更多
关键词 Peak shaving Hybrid energy storage system combined energy storage and transmission grid model Time series operation simulation
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Pressure stimulated current in progressive failure process of combined coal-rock under uniaxial compression:Response and mechanism
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作者 Tiancheng Shan Zhonghui Li +7 位作者 Xin Zhang Haishan Jia Xiaoran Wang Enyuan Wang Yue Niu Dong Chen Weichen Sun Dongming Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期227-243,共17页
Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in undergroun... Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in underground engineering.To reveal the effect of this way,the uniaxial compression experiments with PSC monitoring were conducted on three types of coal-rock combination samples with different strength combinations.The mechanism explanation of PSCs are investigated by resistivity test,atomic force microscopy(AFM)and computed tomography(CT)methods,and a PSC flow model based on progressive failure process is proposed.The influence of strength combinations on PSCs in the progressive failure process are emphasized.The results show the PSC responses between rock part,coal part and the two components are different,which are affected by multi-scale fracture characteristics and electrical properties.As the rock strength decreases,the progressive failure process changes obviously with the influence range of interface constraint effect decreasing,resulting in the different responses of PSC strength and direction in different parts to fracture behaviors.The PSC flow model is initially validated by the relationship between the accumulated charges of different parts.The results are expected to provide a new reference and method for mining design and roadway quality assessment. 展开更多
关键词 combined coal-rock Pressure stimulated current Progressive failure process MECHANISM Flow model
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Winter Wheat Yield Estimation Based on Sparrow Search Algorithm Combined with Random Forest:A Case Study in Henan Province,China
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作者 SHI Xiaoliang CHEN Jiajun +2 位作者 DING Hao YANG Yuanqi ZHANG Yan 《Chinese Geographical Science》 SCIE CSCD 2024年第2期342-356,共15页
Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous r... Precise and timely prediction of crop yields is crucial for food security and the development of agricultural policies.However,crop yield is influenced by multiple factors within complex growth environments.Previous research has paid relatively little attention to the interference of environmental factors and drought on the growth of winter wheat.Therefore,there is an urgent need for more effective methods to explore the inherent relationship between these factors and crop yield,making precise yield prediction increasingly important.This study was based on four type of indicators including meteorological,crop growth status,environmental,and drought index,from October 2003 to June 2019 in Henan Province as the basic data for predicting winter wheat yield.Using the sparrow search al-gorithm combined with random forest(SSA-RF)under different input indicators,accuracy of winter wheat yield estimation was calcu-lated.The estimation accuracy of SSA-RF was compared with partial least squares regression(PLSR),extreme gradient boosting(XG-Boost),and random forest(RF)models.Finally,the determined optimal yield estimation method was used to predict winter wheat yield in three typical years.Following are the findings:1)the SSA-RF demonstrates superior performance in estimating winter wheat yield compared to other algorithms.The best yield estimation method is achieved by four types indicators’composition with SSA-RF)(R^(2)=0.805,RRMSE=9.9%.2)Crops growth status and environmental indicators play significant roles in wheat yield estimation,accounting for 46%and 22%of the yield importance among all indicators,respectively.3)Selecting indicators from October to April of the follow-ing year yielded the highest accuracy in winter wheat yield estimation,with an R^(2)of 0.826 and an RMSE of 9.0%.Yield estimates can be completed two months before the winter wheat harvest in June.4)The predicted performance will be slightly affected by severe drought.Compared with severe drought year(2011)(R^(2)=0.680)and normal year(2017)(R^(2)=0.790),the SSA-RF model has higher prediction accuracy for wet year(2018)(R^(2)=0.820).This study could provide an innovative approach for remote sensing estimation of winter wheat yield.yield. 展开更多
关键词 winter wheat yield estimation sparrow search algorithm combined with random forest(SSA-RF) machine learning multi-source indicator optimal lead time Henan Province China
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A Novel Approach for QoS Prediction Based on Bayesian Combinational Model 被引量:3
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作者 Pengcheng Zhang Yingtao Sun +2 位作者 Hareton Leung Meijun Xu Wenrui Li 《China Communications》 SCIE CSCD 2016年第11期269-280,共12页
As an important factor in evaluating service,QoS(Quality of Service) has drawn more and more concerns with the rapid increasing of Web services. However,due to the great volatility of services in Mobile Internet envir... As an important factor in evaluating service,QoS(Quality of Service) has drawn more and more concerns with the rapid increasing of Web services. However,due to the great volatility of services in Mobile Internet environments,such as internet of vehicles,Web services often do not work as announced and thus cause unacceptable problems. QoS prediction can avoid failure before it takes place,which is considered a more effective way to assure quality. However,Current QoS prediction approaches neither consider the highly dynamic of Web services,nor maintain good prediction performance all the time. Consequently we propose a novel Bayesian combinational model to predict QoS by continuously adjusting credit values of the basic models so as to keep good prediction accuracy. QoS attributes such as response time,throughput and reliability are used to validate the proposed model. Experimental results show that the model can provide stable prediction results in Mobile Internet environments. 展开更多
关键词 预测性能 组合模型 QOS 贝叶斯 WEB服务 移动互联网 服务质量 故障发生
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Quantitative analysis of glutamate compounds in the swine brain following central analgesics nasal spray using proton magnetic resonance spectroscopy and linear combination model
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作者 Jianlin Wu Ting Liu +4 位作者 Yan Lin Zhiwei Shen Yanwei Miao Renhua Wu Changkai Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第7期508-512,共5页
BACKGROUND: In localized brain proton magnetic resonance spectroscopy (^1H-MRS), metabolite levels are often expressed as ratios, rather than absolute concentrations. Frequently, the denominator is creatine, which ... BACKGROUND: In localized brain proton magnetic resonance spectroscopy (^1H-MRS), metabolite levels are often expressed as ratios, rather than absolute concentrations. Frequently, the denominator is creatine, which is assumed to be stable in normal, as well as many pathological, states. However, in vivo creatine levels do not remain constant. Therefore, absolute metabolite measurements, which provide the precise concentrations of certain chemical compounds, are superior to metabolite ratios for determining pathological and evolutional changes. OBJECTIVE: To investigate the feasibility of quantification analysis of brain metabolite changes caused by central analgesics nasal spray using the ^1H-MRS and linear combination model (LCModel) methods. DESIGN, TIME AND SETTING: This neuroimaging, observational, animal study was performed at the Laboratory of the Department of Medical Imaging, Second Affiliated Hospital, Medical College, Shantou University, China from July to December 2007. MATERIALS: Butorphanol tartrate nasal spray, as a mixed agonist-antagonist opioid analgesic, was purchased from Shanghai Hengrui Pharmacy, China. A General Electric Signa 1.5T System (General Electric Medical Systems, Milwaukee, WI, USA) and LCModel software (Stephen Provencher, Oakville, Ontario, Canada) were used in this study. METHODS: MRS images were acquired in ten healthy swine aged 2 weeks using single-voxel point-resolved spectroscopic sequence. A region of interest (2 cm × 2 cm × 2 cm) was placed in the image centers of maximum brain parenchyma. Repeated MRS scanning was performed 15-20 minutes after intranasal administration of 1 mg of butorphanol tartrate. Three settings of repetition time/echo time were selected before and after nasal spray administration 3 000 ms/30 ms,1 500 ms/30 ms, and 3 000 ms/50 ms. Metabolite concentrations were estimated by LCModel software. MAIN OUTCOME MEASURES: ^1H-MRS spectra was obtained using various repetition time/echo time settings. Concentrations of glutamate compounds (glutamate + glutamine), N-acetyl aspartate, and choline were detected in swine brain prior to and following nasal spray treatment. RESULTS: The glutamate compounds curve was consistent with original spectra, when a repetition time/echo time of 3 000 ms/30 ms was adopted. Concentrations of glutamate compounds, N-acetyl aspartate, and choline decreased following administration. The most significant reduction was observed in glutamate compound concentrations from (9.28 ± 0.54) mmol/kg to (7.28 ± 0.54) mmol/kg (P 〈 0.05). CONCLUSION: ^1H-MRS and LCModel software were effectively utilized to quantitatively analyze and measure brain metabolites. Glutamate compounds might be an important neurotransmitter in central analgesia. 展开更多
关键词 proton magnetic resonance spectroscopy nasal spray linear combination model glutamate compounds absolute quantification
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Education Knowledge System Combination Model Based on the Components
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作者 CHEN Lei LI Dehua +1 位作者 LI Xiaojian WU Chunxiang 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1013-1018,共6页
Resources are the base and core of education information, but current web education resources have no structure and it is still difficult to reuse them and make them can be self assembled and developed continually. Ac... Resources are the base and core of education information, but current web education resources have no structure and it is still difficult to reuse them and make them can be self assembled and developed continually. According to the knowledge structure of course and text, the relation among knowledge points, knowledge units from three levels of media material, we can build education resource components, and build TKCM (Teaching Knowledge Combination Model) based on resource components. Builders can build and assemble knowledge system structure and make knowledge units can be self assembled, thus we can develop and consummate them continually. Users can make knowledge units can be self assembled and renewed, and build education knowledge system to satisfy users' demand under the form of education knowledge system. 展开更多
关键词 knowledge unit components education knowledge system knowledge combination model
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Modeling Spatio-temporal Drought Events Based on Multi-temporal,Multi-source Remote Sensing Data Calibrated by Soil Humidity
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作者 LI Hanyu KAUFMANN Hermann XU Guochang 《Chinese Geographical Science》 SCIE CSCD 2022年第1期127-141,共15页
Inspired by recent significant agricultural yield losses in the eastern China and a missing operational monitoring system,we developed a comprehensive drought monitoring model to better understand the impact of indivi... Inspired by recent significant agricultural yield losses in the eastern China and a missing operational monitoring system,we developed a comprehensive drought monitoring model to better understand the impact of individual key factors contributing to this issue.The resulting model,the‘Humidity calibrated Drought Condition Index’(HcDCI)was applied for the years 2001 to 2019 in form of a case study to Weihai County,Shandong Province in East China.Design and development are based on a linear combination of the Vegetation Condition Index(VCI),the Temperature Condition Index(TCI),and the Rainfall Condition Index(RCI)using multi-source satellite data to create a basic Drought Condition Index(DCI).VCI and TCI were derived from MODIS(Moderate Resolution Imaging Spectroradiometer)data,while precipitation is taken from CHIRPS(Climate Hazards Group InfraRed Precipitation with Station data)data.For reasons of accuracy,the decisive coefficients were determined by the relative humidity of soils at depth of 10-20 cm of particular areas collected by an agrometeorological ground station.The correlation between DCI and soil humidity was optimized with the factors of 0.53,0.33,and 0.14 for VCI,TCI,and RCI,respectively.The model revealed,light agricultural droughts from 2003 to 2013 and in 2018,while more severe droughts occurred in 2001 and 2002,2014-2017,and 2019.The droughts were most severe in January,March,and December,and our findings coincide with historical records.The average temperature during 2012-2019 is 1℃ higher than that during the period 2001-2011 and the average precipitation during 2014-2019 is 192.77 mm less than that during 2008-2013.The spatio-temporal accuracy of the HcDCI model was positively validated by correlation with agricultural crop yield quantities.The model thus,demonstrates its capability to reveal drought periods in detail,its transferability to other regions and its usefulness to take future measures. 展开更多
关键词 comprehensive drought model condition indices multi-source satellite data agricultural drought soil humidity
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Forecasting Alzheimer’s Disease Using Combination Model Based on Machine Learning
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作者 He Li Yuhang Wu +2 位作者 Yingnan Zhang Tao Wei Yufeng Gui 《Applied Mathematics》 2018年第4期403-417,共15页
As the acceleration of aged population tendency, building models to forecast Alzheimer’s Disease (AD) is essential. In this article, we surveyed 1157 interviewees. By analyzing the results using three machine learnin... As the acceleration of aged population tendency, building models to forecast Alzheimer’s Disease (AD) is essential. In this article, we surveyed 1157 interviewees. By analyzing the results using three machine learning methods—BP neural network, SVM and random forest, we can derive the accuracy of them in forecasting AD, so that we can compare the methods in solving AD prediction. Among them, random forest is the most accurate method. Moreover, to combine the advantages of the methods, we build a new combination forecasting model based on the three machine learning models, which is proved more accurate than the models singly. At last, we give the conclusion of the connection between life style and AD, and provide several suggestions for elderly people to help them prevent AD. 展开更多
关键词 Alzheimer’s Disease BP NEURAL Network SVM RANDOM FOREST combination Forecasting model
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Multi-Source Spatial Data Distribution Model and System Implementation
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作者 Jing Liu Xiancheng Mao 《Communications and Network》 2013年第1期93-98,共6页
The Multi-source spatial data distribution is based on WebGIS, and it is an important part of multi-source geographic information management system. a new multi-source spatial data distribution model is proposed on th... The Multi-source spatial data distribution is based on WebGIS, and it is an important part of multi-source geographic information management system. a new multi-source spatial data distribution model is proposed on the basis of multisource data storage model and by combining existing map distribution technology, The author developed a multi-source spatial data distribution system which based on MapGIS K9 by using this model and taking full advantage of interfacecode separating thinking and high efficiency characteristic of .net, so high-speed distribution of multi-source spatial data realized. 展开更多
关键词 multi-source SPATIAL DATA DISTRIBUTION model WEBGIS MAPGIS K9
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