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A Survey of Federated Learning:Advances in Architecture,Synchronization,and Security Threats
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作者 Faisal Mahmud Fahim Mahmud Rashedur M.Rahman 《Computers, Materials & Continua》 2026年第3期1-87,共87页
Federated Learning(FL)has become a leading decentralized solution that enables multiple clients to train a model in a collaborative environment without directly sharing raw data,making it suitable for privacy-sensitiv... Federated Learning(FL)has become a leading decentralized solution that enables multiple clients to train a model in a collaborative environment without directly sharing raw data,making it suitable for privacy-sensitive applications such as healthcare,finance,and smart systems.As the field continues to evolve,the research field has become more complex and scattered,covering different system designs,training methods,and privacy techniques.This survey is organized around the three core challenges:how the data is distributed,how models are synchronized,and how to defend against attacks.It provides a structured and up-to-date review of FL research from 2023 to 2025,offering a unified taxonomy that categorizes works by data distribution(Horizontal FL,Vertical FL,Federated Transfer Learning,and Personalized FL),training synchronization(synchronous and asynchronous FL),optimization strategies,and threat models(data leakage and poisoning attacks).In particular,we summarize the latest contributions in Vertical FL frameworks for secure multi-party learning,communication-efficient Horizontal FL,and domain-adaptive Federated Transfer Learning.Furthermore,we examine synchronization techniques addressing system heterogeneity,including straggler mitigation in synchronous FL and staleness management in asynchronous FL.The survey covers security threats in FL,such as gradient inversion,membership inference,and poisoning attacks,as well as their defense strategies that include privacy-preserving aggregation and anomaly detection.The paper concludes by outlining unresolved issues and highlighting challenges in handling personalized models,scalability,and real-world adoption. 展开更多
关键词 Federated learning(FL) horizontal federated learning(HFL) vertical federated learning(VFL) federated transfer learning(FTL) personalized federated learning synchronous federated learning(SFL) asynchronous federated learning(AFL) data leakage poisoning attacks privacy-preserving machine learning
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Enhancing IoT Resilience at the Edge:A Resource-Efficient Framework for Real-Time Anomaly Detection in Streaming Data
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作者 Kirubavathi G. Arjun Pulliyasseri +5 位作者 Aswathi Rajesh Amal Ajayan Sultan Alfarhood Mejdl Safran Meshal Alfarhood Jungpil Shin 《Computer Modeling in Engineering & Sciences》 2025年第6期3005-3031,共27页
The exponential expansion of the Internet of Things(IoT),Industrial Internet of Things(IIoT),and Transportation Management of Things(TMoT)produces vast amounts of real-time streaming data.Ensuring system dependability... The exponential expansion of the Internet of Things(IoT),Industrial Internet of Things(IIoT),and Transportation Management of Things(TMoT)produces vast amounts of real-time streaming data.Ensuring system dependability,operational efficiency,and security depends on the identification of anomalies in these dynamic and resource-constrained systems.Due to their high computational requirements and inability to efficiently process continuous data streams,traditional anomaly detection techniques often fail in IoT systems.This work presents a resource-efficient adaptive anomaly detection model for real-time streaming data in IoT systems.Extensive experiments were carried out on multiple real-world datasets,achieving an average accuracy score of 96.06%with an execution time close to 7.5 milliseconds for each individual streaming data point,demonstrating its potential for real-time,resourceconstrained applications.The model uses Principal Component Analysis(PCA)for dimensionality reduction and a Z-score technique for anomaly detection.It maintains a low computational footprint with a sliding window mechanism,enabling incremental data processing and identification of both transient and sustained anomalies without storing historical data.The system uses a Multivariate Linear Regression(MLR)based imputation technique that estimates missing or corrupted sensor values,preserving data integrity prior to anomaly detection.The suggested solution is appropriate for many uses in smart cities,industrial automation,environmental monitoring,IoT security,and intelligent transportation systems,and is particularly well-suited for resource-constrained edge devices. 展开更多
关键词 Anomaly detection streaming data IOT IIoT TMoT real-time LIGHTWEIGHT modeling
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Real-time Synchronization Method Based on Dual Ring Fieldbus in CNC System 被引量:2
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作者 YANG Lei LIN Hu +3 位作者 ZHENG Liaomo YUE Dongfeng GAO Tianrong WANG Feng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第1期111-121,共11页
As the popularization of dual ring fieldbus, the optimized dual ring synchronization methods are still in short. The current synchronization methods are generally established in traditional industrial fieldbus, in whi... As the popularization of dual ring fieldbus, the optimized dual ring synchronization methods are still in short. The current synchronization methods are generally established in traditional industrial fieldbus, in which transmission is commonly considered in single track, the two-way transmitting cannot take full effect, and would result in unwanted idle load on equipment lines. In stamp-transferring part, the synchronizing algorithm is not properly processed to diminish the latency, so the real-time performance of entire system cannot be ensured. To support the synchronization control of stations in the CNC system, a real-time time synchronization method for dual ring fieldbus in the CNC system is designed in this paper. In this method a synchronizing message transmission scheme based on dual ring architecture and the synchronization algorithm between master and secondary stations are integrated. In the scheme, the clock models of both master and secondary stations are optimized with corresponding modules and the stamp data transmission based on the dual ring fieldbus is devised exclusively, so the transmitting efficiency improves with less idle work. In the algorithm, all the secondary stations can accomplish the consistent state with master station by updating clock discrepancy information in one communication cycle, and it takes the advantage of two-way transmitting and makes the best use of dual ring structure, so the real-time performance of the system can be promoted while retaining the precision of synchronization. To evaluate the performance, the costs of the method and errors during synchronizing are noted and analyzed based on the actual running environment in the industrial fieldbus. The results show that it reduces communication cost and ensures the smoothness of the system with low lag effects under heavy load. The proposed time synchronization method optimizes the architecture of sync message transmission in dual ring fieldbus, and improves the efficiency of time synchronization in the stations of CNC system. 展开更多
关键词 time synchronization dual ring fieldbus real-time system CNC system
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SET-MRTS:An Empirical Experiment Tool for Real-Time Scheduling and Synchronization
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作者 Ze-Wei Chen Hang Lei +1 位作者 Mao-Lin Yang Yong Liao 《Journal of Electronic Science and Technology》 CAS CSCD 2022年第1期30-42,共13页
In the real-time scheduling theory,schedulability and synchronization analyses are used to evaluate scheduling algorithms and real-time locking protocols,respectively,and the empirical synthesis experiment is one of t... In the real-time scheduling theory,schedulability and synchronization analyses are used to evaluate scheduling algorithms and real-time locking protocols,respectively,and the empirical synthesis experiment is one of the major methods to compare the performance of such analyses.However,since many sophisticated techniques have been adopted to improve the analytical accuracy,the implementation of such analyses and experiments is often time-consuming.This paper proposes a schedulability experiment toolkit for multiprocessor real-time systems(SET-MRTS),which provides a framework with infrastructures to implement the schedulability and synchronization analyses and the deployment of empirical synthesis experiments.Besides,with well-designed peripheral components for the input and output,experiments can be conducted easily and flexibly on SET-MRTS.This demonstration further proves the effectiveness of SET-MRTS in both functionality and availability. 展开更多
关键词 EXPERIMENT real-time system SCHEDULABILITY software tools synchronization
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Data synchronization in IMU/GPS integrated measurement system of vehicle motion parameters 被引量:5
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作者 刘广孚 张为公 +1 位作者 李旭 郭亮 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期200-203,共4页
To realize the data synchronization between the inertial measurement unit (IMU) and the global positioning system (GPS), the synchronization technology in the IMU/GPS integrated measurement system of vehicle motio... To realize the data synchronization between the inertial measurement unit (IMU) and the global positioning system (GPS), the synchronization technology in the IMU/GPS integrated measurement system of vehicle motion parameters is studied. According to the characteristics of the output signals of the IMU and the GPS, without the IMU synchronization signal, the synchronization circuit based on CPLD is designed and developed, which need not alter the configurations of the IMU and GPS. Experiments of measuring vehicle motion parameters, which rely on the synchronization circuit to realize IMU/GPS data synchronization, are made. The driving routes in experiments comprise a curve and a straight line. Experimental results show that the designed circuit can accurately measure the synchronization time difference and the IMU period, and can effectively solve the data synchronization in IMU/GPS integration. Furthermore, the IMU/GPS integrated measurement system based on the synchronization circuit can measure and calculate many vehicle motion parameters in high frequency mode. 展开更多
关键词 vehicle movement performance test IMU/GPS data synchronization
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High-SpeedReal-TimeDataAcquisitionSystem Realized by Interleaving/Multiplexing Technique 被引量:1
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作者 吕洁 莫毅群 罗伟雄 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期183-188,共6页
The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improv... The interleaving/multiplexing technique was used to realize a 200?MHz real time data acquisition system. Two 100?MHz ADC modules worked parallelly and every ADC plays out data in ping pang fashion. The design improved the system conversion rata to 200?MHz and reduced the speed of data transporting and storing to 50?MHz. The high speed HDPLD and ECL logic parts were used to control system timing and the memory address. The multi layer print board and the shield were used to decrease interference produced by the high speed circuit. The system timing was designed carefully. The interleaving/multiplexing technique could improve the system conversion rata greatly while reducing the speed of external digital interfaces greatly. The design resolved the difficulties in high speed system effectively. The experiment proved the data acquisition system is stable and accurate. 展开更多
关键词 real-time data acquisition interleaving/multiplexing high-speed AD converter
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SECURE DATA SYNCHRONIZATION EXCHANGE SERVICE APPLICATION PROGRAM INTERFACE BASED ON SyncML PROTOCOL
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作者 王立松 李杰 +1 位作者 王海峰 丁秋林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第1期47-51,共5页
The security-related problem during the data exchange is not considered in the SyncML protocol. To solve this problem, SyncML is enhanced with a secure data synchronization exchange service application program interfa... The security-related problem during the data exchange is not considered in the SyncML protocol. To solve this problem, SyncML is enhanced with a secure data synchronization exchange service application program interface (SDSXS-API) to ensure the reliability, the integrity, and the security in the data transmission and exchange. The design and the implementation of SDSXS-API are also given. The proposed APIs can be conveniently used as a uniform exchange interface for any related application programs. And their effectiveness is verified in the prototype mobile database system. 展开更多
关键词 SYNCML mobile computing synchronization data security
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Quality control of marine big data——a case study of real-time observation station data in Qingdao 被引量:8
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作者 QIAN Chengcheng LIU Aichao +4 位作者 HUANG Rui LIU Qingrong XU Wenkun ZHONG Shan YU Le 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第6期1983-1993,共11页
Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great s... Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great significance for exploiting and protecting the ocean.We used hourly mean wave height,temperature,and pressure real-time observation data taken in the Xiaomaidao station(in Qingdao,China)from June 1,2017,to May 31,2018,to explore the data quality using eight quality control methods,and to discriminate the most effective method for Xiaomaidao station.After using the eight quality control methods,the percentages of the mean wave height,temperature,and pressure data that passed the tests were 89.6%,88.3%,and 98.6%,respectively.With the marine disaster(wave alarm report)data,the values failed in the test mainly due to the influence of aging observation equipment and missing data transmissions.The mean wave height is often affected by dynamic marine disasters,so the continuity test method is not effective.The correlation test with other related parameters would be more useful for the mean wave height. 展开更多
关键词 quality control real-time STATION data MARINE BIG data Xiaomaidao STATION MARINE DISASTER
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Design and FPGA verification of a novel reliable real-time data transfer system 被引量:3
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作者 Yu-ping LIAN Yan HAN +2 位作者 Ming-xu HUO Jin-long CHEN Yan ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1406-1410,共5页
Considering the increasing use of information technology with established standards, such as TCP/IP and XML in modem industrial automation, we present a high cost performance solution with FPGA (field programmable ga... Considering the increasing use of information technology with established standards, such as TCP/IP and XML in modem industrial automation, we present a high cost performance solution with FPGA (field programmable gate array) implementation of a novel reliable real-time data transfer system based on EPA (Ethemet for plant automation) protocol and IEEE 1588 standard. This combination can provide more predictable and real-time communication between automation equipments and precise synchronization between devices. The designed EPA system has been verified on Xilinx Spartan3 XC3S1500 and it consumed 75% of the total slices. The experimental results show that the novel industrial control system achieves high synchronization precision and provides a 1.59-ps standard deviation between the master device and the slave ones. Such a real-time data transfer system is an excellent candidate for automation equipments which require precise synchronization based on Ethemet at a comparatively low price. 展开更多
关键词 Ethemet for plant automation (EPA) IEEE 1588 Precise synchronization real-time data transfer
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Variation of spatio-temporal distribution of on-road vehicle emissions based on real-time RFID data 被引量:5
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作者 Yonghong Liu Wenfeng Huang +3 位作者 Xiaofang Lin Rui Xu Li Li Hui Ding 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第6期151-162,共12页
High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution ... High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution in the main urban area of Chongqing, based on realtime traffic data from 820 RFID detectors covering 454 roads, and the differences in spatiotemporal emission characteristics between inner and outer districts were analysed. The result showed that the daily vehicular emission intensities of CO, hydrocarbons, PM2.5, PM10,and NO_(x) were 30.24, 3.83, 0.18, 0.20, and 8.65 kg/km per day, respectively, in the study area during 2018. The pollutants emission intensities in inner district were higher than those in outer district. Light passenger cars(LPCs) were the main contributors of all-day CO emissions in the inner and outer districts, from which the contributors of NO_(x) emissions were different. Diesel and natural gas buses were major contributors of daytime NO_(x) emissions in inner districts, accounting for 40.40%, but buses and heavy duty trucks(HDTs) were major contributors in outer districts. At nighttime, due to the lifting of truck restrictions and suspension of buses, HDTs become the main NO_(x) contributor in both inner and outer districts,and its three NO_(x) emission peak hours were found, which are different to the peak hours of total NO_(x) emission by all vehicles. Unlike most other cities, bridges and connecting channels are always emission hotspots due to long-time traffic congestion. This knowledge will help fully understand vehicular emissions characteristics and is useful for policymakers to design precise prevention and control measures. 展开更多
关键词 Spatio-temporal distribution Link-level vehicular emission INVENTORY real-time RFID data HDTs CHONGQING
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Data network traffic analysis and optimization strategy of real-time power grid dynamic monitoring system for wide-frequency measurements 被引量:4
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作者 Jinsong Li Hao Liu +2 位作者 Wenzhuo Li Tianshu Bi Mingyang Zhao 《Global Energy Interconnection》 EI CAS CSCD 2022年第2期131-142,共12页
The application and development of a wide-area measurement system(WAMS)has enabled many applications and led to several requirements based on dynamic measurement data.Such data are transmitted as big data information ... The application and development of a wide-area measurement system(WAMS)has enabled many applications and led to several requirements based on dynamic measurement data.Such data are transmitted as big data information flow.To ensure effective transmission of wide-frequency electrical information by the communication protocol of a WAMS,this study performs real-time traffic monitoring and analysis of the data network of a power information system,and establishes corresponding network optimization strategies to solve existing transmission problems.This study utilizes the traffic analysis results obtained using the current real-time dynamic monitoring system to design an optimization strategy,covering the optimization in three progressive levels:the underlying communication protocol,source data,and transmission process.Optimization of the system structure and scheduling optimization of data information are validated to be feasible and practical via tests. 展开更多
关键词 Power system data network Wide-frequency information real-time system Traffic analysis Optimization strategy
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Real-time prediction of mechanical behaviors of underwater shield tunnel structure using machine learning method based on structural health monitoring data 被引量:3
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作者 Xuyan Tan Weizhong Chen +2 位作者 Tao Zou Jianping Yang Bowen Du 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期886-895,共10页
Predicting the mechanical behaviors of structure and perceiving the anomalies in advance are essential to ensuring the safe operation of infrastructures in the long run.In addition to the incomplete consideration of i... Predicting the mechanical behaviors of structure and perceiving the anomalies in advance are essential to ensuring the safe operation of infrastructures in the long run.In addition to the incomplete consideration of influencing factors,the prediction time scale of existing studies is rough.Therefore,this study focuses on the development of a real-time prediction model by coupling the spatio-temporal correlation with external load through autoencoder network(ATENet)based on structural health monitoring(SHM)data.An autoencoder mechanism is performed to acquire the high-level representation of raw monitoring data at different spatial positions,and the recurrent neural network is applied to understanding the temporal correlation from the time series.Then,the obtained temporal-spatial information is coupled with dynamic loads through a fully connected layer to predict structural performance in next 12 h.As a case study,the proposed model is formulated on the SHM data collected from a representative underwater shield tunnel.The robustness study is carried out to verify the reliability and the prediction capability of the proposed model.Finally,the ATENet model is compared with some typical models,and the results indicate that it has the best performance.ATENet model is of great value to predict the realtime evolution trend of tunnel structure. 展开更多
关键词 Shied tunnel Machine learning MONITORING real-time prediction data analysis
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DSP-free coherent receivers in frequency-synchronous optical networks for next-generation data center interconnects 被引量:1
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作者 Lei Liu Feng Liu +2 位作者 Cheng Peng Bo Xue William Shieh 《Advanced Photonics Nexus》 2025年第3期141-148,共8页
Propelled by the rise of artificial intelligence,cloud services,and data center applications,next-generation,low-power,local-oscillator-less,digital signal processing(DSP)-free,and short-reach coherent optical communi... Propelled by the rise of artificial intelligence,cloud services,and data center applications,next-generation,low-power,local-oscillator-less,digital signal processing(DSP)-free,and short-reach coherent optical communication has evolved into an increasingly prominent area of research in recent years.Here,we demonstrate DSP-free coherent optical transmission by analog signal processing in frequency synchronous optical network(FSON)architecture,which supports polarization multiplexing and higher-order modulation formats.The FSON architecture that allows the numerous laser sources of optical transceivers within a data center can be quasi-synchronized by means of a tree-distributed homology architecture.In conjunction with our proposed pilot-tone assisted Costas loop for an analog coherent receiver,we achieve a record dual-polarization 224-Gb/s 16-QAM 5-km mismatch transmission with reset-free carrier phase recovery in the optical domain.Our proposed DSP-free analog coherent detection system based on the FSON makes it a promising solution for next-generation,low-power,and high-capacity coherent data center interconnects. 展开更多
关键词 digital signal processing-free data center interconnect frequency synchronous optical network analog signal processing
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IoT-Based Real-Time Medical-Related Human Activity Recognition Using Skeletons and Multi-Stage Deep Learning for Healthcare 被引量:1
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作者 Subrata Kumer Paul Abu Saleh Musa Miah +3 位作者 Rakhi Rani Paul Md.EkramulHamid Jungpil Shin Md Abdur Rahim 《Computers, Materials & Continua》 2025年第8期2513-2530,共18页
The Internet of Things(IoT)and mobile technology have significantly transformed healthcare by enabling real-time monitoring and diagnosis of patients.Recognizing Medical-Related Human Activities(MRHA)is pivotal for he... The Internet of Things(IoT)and mobile technology have significantly transformed healthcare by enabling real-time monitoring and diagnosis of patients.Recognizing Medical-Related Human Activities(MRHA)is pivotal for healthcare systems,particularly for identifying actions critical to patient well-being.However,challenges such as high computational demands,low accuracy,and limited adaptability persist in Human Motion Recognition(HMR).While some studies have integrated HMR with IoT for real-time healthcare applications,limited research has focused on recognizing MRHA as essential for effective patient monitoring.This study proposes a novel HMR method tailored for MRHA detection,leveraging multi-stage deep learning techniques integrated with IoT.The approach employs EfficientNet to extract optimized spatial features from skeleton frame sequences using seven Mobile Inverted Bottleneck Convolutions(MBConv)blocks,followed by Convolutional Long Short Term Memory(ConvLSTM)to capture spatio-temporal patterns.A classification module with global average pooling,a fully connected layer,and a dropout layer generates the final predictions.The model is evaluated on the NTU RGB+D 120 and HMDB51 datasets,focusing on MRHA such as sneezing,falling,walking,sitting,etc.It achieves 94.85%accuracy for cross-subject evaluations and 96.45%for cross-view evaluations on NTU RGB+D 120,along with 89.22%accuracy on HMDB51.Additionally,the system integrates IoT capabilities using a Raspberry Pi and GSM module,delivering real-time alerts via Twilios SMS service to caregivers and patients.This scalable and efficient solution bridges the gap between HMR and IoT,advancing patient monitoring,improving healthcare outcomes,and reducing costs. 展开更多
关键词 real-time human motion recognition(HMR) ENConvLSTM EfficientNet ConvLSTM skeleton data NTU RGB+D 120 dataset MRHA
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Design and development of real-time query platform for big data based on hadoop 被引量:1
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作者 刘小利 Xu Pandeng +1 位作者 Liu Mingliang Zhu Guobin 《High Technology Letters》 EI CAS 2015年第2期231-238,共8页
This paper designs and develops a framework on a distributed computing platform for massive multi-source spatial data using a column-oriented database(HBase).This platform consists of four layers including ETL(extract... This paper designs and develops a framework on a distributed computing platform for massive multi-source spatial data using a column-oriented database(HBase).This platform consists of four layers including ETL(extraction transformation loading) tier,data processing tier,data storage tier and data display tier,achieving long-term store,real-time analysis and inquiry for massive data.Finally,a real dataset cluster is simulated,which are made up of 39 nodes including 2 master nodes and 37 data nodes,and performing function tests of data importing module and real-time query module,and performance tests of HDFS's I/O,the MapReduce cluster,batch-loading and real-time query of massive data.The test results indicate that this platform achieves high performance in terms of response time and linear scalability. 展开更多
关键词 big data massive data storage real-time query HADOOP distributed computing
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Web-based GIS System for Real-time Field Data Collection Using Personal Mobile Phone 被引量:2
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作者 Ko Ko Lwin Yuji Murayama 《Journal of Geographic Information System》 2011年第4期382-389,共8页
Recently, use of mobile communicational devices in field data collection is increasing such as smart phones and cellular phones due to emergence of embedded Global Position System GPS and Wi-Fi Internet access. Accura... Recently, use of mobile communicational devices in field data collection is increasing such as smart phones and cellular phones due to emergence of embedded Global Position System GPS and Wi-Fi Internet access. Accurate timely and handy field data collection is required for disaster management and emergency quick responses. In this article, we introduce web-based GIS system to collect the field data by personal mobile phone through Post Office Protocol POP3 mail server. The main objective of this work is to demonstrate real-time field data collection method to the students using their mobile phone to collect field data by timely and handy manners, either individual or group survey in local or global scale research. 展开更多
关键词 WEB-BASED GIS System real-time Field data Collection PERSONAL Mobile PHONE POP3 MAIL Server
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Scheduling transactions in mobile distributed real-time database systems 被引量:1
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作者 雷向东 赵跃龙 +1 位作者 陈松乔 袁晓莉 《Journal of Central South University of Technology》 EI 2008年第4期545-551,共7页
A DMVOCC-MVDA (distributed multiversion optimistic concurrency control with multiversion dynamic adjustment) protocol was presented to process mobile distributed real-time transaction in mobile broadcast environment... A DMVOCC-MVDA (distributed multiversion optimistic concurrency control with multiversion dynamic adjustment) protocol was presented to process mobile distributed real-time transaction in mobile broadcast environments. At the mobile hosts, all transactions perform local pre-validation. The local pre-validation process is carried out against the committed transactions at the server in the last broadcast cycle. Transactions that survive in local pre-validation must be submitted to the server for local final validation. The new protocol eliminates conflicts between mobile read-only and mobile update transactions, and resolves data conflicts flexibly by using multiversion dynamic adjustment of serialization order to avoid unnecessary restarts of transactions. Mobile read-only transactions can be committed with no-blocking, and respond time of mobile read-only transactions is greatly shortened. The tolerance of mobile transactions of disconnections from the broadcast channel is increased. In global validation mobile distributed transactions have to do check to ensure distributed serializability in all participants. The simulation results show that the new concurrency control protocol proposed offers better performance than other protocols in terms of miss rate, restart rate, commit rate. Under high work load (think time is ls) the miss rate of DMVOCC-MVDA is only 14.6%, is significantly lower than that of other protocols. The restart rate of DMVOCC-MVDA is only 32.3%, showing that DMVOCC-MVDA can effectively reduce the restart rate of mobile transactions. And the commit rate of DMVOCC-MVDA is up to 61.2%, which is obviously higher than that of other protocols. 展开更多
关键词 mobile distributed real-time database systems muliversion optimistic concurrency control multiversion dynamic adjustment pre-validation multiversion data broadcast
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Synchronous Detection of DNA/RNA of Four Shrimp Viruses by Real-time Fluorescence Quantitative RT-PCR 被引量:1
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作者 Biao SHEN Zhongfa WANG +1 位作者 Xingjuan HU Songye GU 《Agricultural Biotechnology》 CAS 2014年第5期48-50,共3页
[ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel rea... [ Objective] This study aimed to establish a simultaneous detection method of shrimp viruses by real-time fluorescence quantitative RT-PCR, to improve the efficiency of inspection and quarantine. [ Method] A novel real-time fluorescence quantitative RT-PCR assay was established and optimized for simultaneously detecting DNA/RNA of four shrimp viruses (WSSV, IHHNV, TSV and YHV ). [ Result] The optimized real-time fluorescence quantitative RT-PCR system gener- ated typical amplification curves with high amplification efficiencies (E = 1.06, 1.07, 0.92 and 0.92, respectively), good hnear relationship ( r = 1 ), uniform repeatability ( standard deviation = 0.05 - 0.46 ; variation coefficient = 0.26% - 1.62% ) and high sensitivity, exhibiting no significant differences compared with re- al-time fluorescence quantitative PCR (average error of Ct value = 0.04 -0.40; T = 0.53 -2.50; P 〉 0.05 ). The total detection time was about 1 h. [ Conclusion] The optimized real-time fluorescence quantitative RT-PCR system can be used for rapid detection of WSSV, IHHNV, TSV and YHV. 展开更多
关键词 real-time fluorescence quantitative RT-PCR Shrimp viruses synchronous amplification of DNA/RNA
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Integrated Real-Time Big Data Stream Sentiment Analysis Service 被引量:1
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作者 Sun Sunnie Chung Danielle Aring 《Journal of Data Analysis and Information Processing》 2018年第2期46-66,共21页
Opinion (sentiment) analysis on big data streams from the constantly generated text streams on social media networks to hundreds of millions of online consumer reviews provides many organizations in every field with o... Opinion (sentiment) analysis on big data streams from the constantly generated text streams on social media networks to hundreds of millions of online consumer reviews provides many organizations in every field with opportunities to discover valuable intelligence from the massive user generated text streams. However, the traditional content analysis frameworks are inefficient to handle the unprecedentedly big volume of unstructured text streams and the complexity of text analysis tasks for the real time opinion analysis on the big data streams. In this paper, we propose a parallel real time sentiment analysis system: Social Media Data Stream Sentiment Analysis Service (SMDSSAS) that performs multiple phases of sentiment analysis of social media text streams effectively in real time with two fully analytic opinion mining models to combat the scale of text data streams and the complexity of sentiment analysis processing on unstructured text streams. We propose two aspect based opinion mining models: Deterministic and Probabilistic sentiment models for a real time sentiment analysis on the user given topic related data streams. Experiments on the social media Twitter stream traffic captured during the pre-election weeks of the 2016 Presidential election for real-time analysis of public opinions toward two presidential candidates showed that the proposed system was able to predict correctly Donald Trump as the winner of the 2016 Presidential election. The cross validation results showed that the proposed sentiment models with the real-time streaming components in our proposed framework delivered effectively the analysis of the opinions on two presidential candidates with average 81% accuracy for the Deterministic model and 80% for the Probabilistic model, which are 1% - 22% improvements from the results of the existing literature. 展开更多
关键词 SENTIMENT ANALYSIS real-time Text ANALYSIS OPINION ANALYSIS BIG data An-alytics
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Real-time performance of periodic data transmission in EPA industrial Ethernet 被引量:2
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作者 刘宁 仲崇权 莫亚林 《Journal of Beijing Institute of Technology》 EI CAS 2012年第3期336-342,共7页
To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By... To evaluate and improve the real-time performance of Ethernet for plant automation(EPA) industrial Ethernet,the real-time performance of EPA periodic data transmission was theoretically and experimentally studied.By analyzing information transmission regularity and EPA deterministic scheduling mechanism,periodic messages were categorized as different modes according to their entering-queue time.The scheduling characteristics and delivery time of each mode and their interacting relations were studied,during which the models of real-time performance of periodic information transmission in EPA system were established.On this basis,an experimental platform is developed to test the delivery time of periodic messages transmission in EPA system.According to the analysis and the experiment,the main factors that limit the real-time performance of EPA periodic data transmission and the improvement methods were proposed. 展开更多
关键词 Ethernet for plant automation(EPA) industrial Ethernet periodic data transmission real-time performance delivery time
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