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Real-Time Wind Speed Analysis at Wind-Damaged Tower of a Transmission Line
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作者 Jiehua Ding Xiaoling Yang Yongsheng Zhao 《Journal of Electronic Research and Application》 2024年第6期58-65,共8页
Affected by the Super Typhoon“Mangkhut,”a total of five base towers of a transmission line in the mountainous area of China collapsed.In this paper,a mathematical model is established based on the Shuttle Radar Topo... Affected by the Super Typhoon“Mangkhut,”a total of five base towers of a transmission line in the mountainous area of China collapsed.In this paper,a mathematical model is established based on the Shuttle Radar Topography Mission(SRTM)data near the accident tower.The measured wind speed in the plain area under the mountain is used as the calculation boundary condition.The wind speed at the top of the mountain is calculated by using a numerical simulation method.The design wind speed and calculated wind speed at the tower site are compared,and the influence of wind speed on tower position in this wind disaster accident is analyzed. 展开更多
关键词 Power transmission line Wind disaster Design wind speed real-time wind speed Numerical simulation
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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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Reliable Data Collection Model and Transmission Framework in Large-Scale Wireless Medical Sensor Networks
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作者 Haosong Gou Gaoyi Zhang +2 位作者 RenêRipardo Calixto Senthil Kumar Jagatheesaperumal Victor Hugo C.de Albuquerque 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1077-1102,共26页
Large-scale wireless sensor networks(WSNs)play a critical role in monitoring dangerous scenarios and responding to medical emergencies.However,the inherent instability and error-prone nature of wireless links present ... Large-scale wireless sensor networks(WSNs)play a critical role in monitoring dangerous scenarios and responding to medical emergencies.However,the inherent instability and error-prone nature of wireless links present significant challenges,necessitating efficient data collection and reliable transmission services.This paper addresses the limitations of existing data transmission and recovery protocols by proposing a systematic end-to-end design tailored for medical event-driven cluster-based large-scale WSNs.The primary goal is to enhance the reliability of data collection and transmission services,ensuring a comprehensive and practical approach.Our approach focuses on refining the hop-count-based routing scheme to achieve fairness in forwarding reliability.Additionally,it emphasizes reliable data collection within clusters and establishes robust data transmission over multiple hops.These systematic improvements are designed to optimize the overall performance of the WSN in real-world scenarios.Simulation results of the proposed protocol validate its exceptional performance compared to other prominent data transmission schemes.The evaluation spans varying sensor densities,wireless channel conditions,and packet transmission rates,showcasing the protocol’s superiority in ensuring reliable and efficient data transfer.Our systematic end-to-end design successfully addresses the challenges posed by the instability of wireless links in large-scaleWSNs.By prioritizing fairness,reliability,and efficiency,the proposed protocol demonstrates its efficacy in enhancing data collection and transmission services,thereby offering a valuable contribution to the field of medical event-drivenWSNs. 展开更多
关键词 Wireless sensor networks reliable data transmission medical emergencies CLUSTER data collection routing scheme
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Enabling Efficient Data Transmission in Wireless Sensor Networks-Based IoT Application
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作者 Ibraheem Al-Hejri Farag Azzedin +1 位作者 Sultan Almuhammadi Naeem Firdous Syed 《Computers, Materials & Continua》 SCIE EI 2024年第6期4197-4218,共22页
The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure ... The use of the Internet of Things(IoT)is expanding at an unprecedented scale in many critical applications due to the ability to interconnect and utilize a plethora of wide range of devices.In critical infrastructure domains like oil and gas supply,intelligent transportation,power grids,and autonomous agriculture,it is essential to guarantee the confidentiality,integrity,and authenticity of data collected and exchanged.However,the limited resources coupled with the heterogeneity of IoT devices make it inefficient or sometimes infeasible to achieve secure data transmission using traditional cryptographic techniques.Consequently,designing a lightweight secure data transmission scheme is becoming essential.In this article,we propose lightweight secure data transmission(LSDT)scheme for IoT environments.LSDT consists of three phases and utilizes an effective combination of symmetric keys and the Elliptic Curve Menezes-Qu-Vanstone asymmetric key agreement protocol.We design the simulation environment and experiments to evaluate the performance of the LSDT scheme in terms of communication and computation costs.Security and performance analysis indicates that the LSDT scheme is secure,suitable for IoT applications,and performs better in comparison to other related security schemes. 展开更多
关键词 IoT LIGHTWEIGHT computation complexity communication overhead cybersecurity threats threat prevention secure data transmission Wireless Sensor Networks(WSNs) elliptic curve cryptography
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Modeling and Statistical Properties Research on Online Real-Time Information Transmission Network 被引量:2
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作者 Guangming Deng Zhen Jia 《Open Journal of Applied Sciences》 2014年第5期234-241,共8页
In this paper, the model of the online real-time information transmission network, such as wechat, micro-blog, and QQ network, is proposed and built, based on the connection properties between users of the online real... In this paper, the model of the online real-time information transmission network, such as wechat, micro-blog, and QQ network, is proposed and built, based on the connection properties between users of the online real-time information transmission network, and combined with the local world evolving characteristics in complex network, then the statistical topological properties of the network is obtained by numerical simulation. Furthermore, we simulated the process of information transmission on the network, according to the actual characteristics of the online real-time information transmission. Statistics show that the degree distribution presents the characteristics of scale free network, presenting power law distribution, while the average path length, the average clustering coefficient and the average size of the network also has a power-law relationship, moreover, the model parameters has no effect on power-law exponent. The spread of information on the network represents obvious fluctuation scaling, reflecting the characteristics that information transmission fluctuates over time. 展开更多
关键词 Network INFORMATION transmission real-time INFORMATION FLUCTUATION SCALING
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Transmission Considerations with QoS Support to Deliver Real-Time Distributed Speech Recognition Applications
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作者 Zhu Xiao-gang Zhu Hong-wen Rong Meng-tian 《Wuhan University Journal of Natural Sciences》 EI CAS 2002年第1期65-70,共6页
Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless... Distributed speech recognition (DSR) applications have certain QoS (Quality of service) requirements in terms of latency, packet loss rate, etc. To deliver quality guaranteed DSR application over wirelined or wireless links, some QoS mechanisms should be provided. We put forward a RTP/RSVP transmission scheme with DSR-specific payload and QoS parameters by modifying the present WAP protocol stack. The simulation result shows that this scheme will provide adequate network bandwidth to keep the real-time transport of DSR data over either wirelined or wireless channels. 展开更多
关键词 distributed speech recognition quality of service real-time transmission protocol resource reservation protocol wireless application protocol
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Development of 16-channels Compact EEG System Using Real-time High-speed Wireless Transmission
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作者 B. R. Myung S. K. Yoo 《Engineering(科研)》 2013年第5期93-97,共5页
For the convenience of people with disability and for normal people, a demand for intelligent interfaces is ever increasing and therefore related studies are actively being conducted. Recently a study is being conduct... For the convenience of people with disability and for normal people, a demand for intelligent interfaces is ever increasing and therefore related studies are actively being conducted. Recently a study is being conducted to develop an interface through face expression, movement of the body and eye movements, and further more active attempts to use electrical signals(brainwave, electrocardiogram, electromyogram) measured from the human body is also actively being progressed. In addition, the development and the usage of mobile devices and smart devices are promoting these research activities even more. The brainwave is measured by electrical activities between nerve cells in the cerebral cortex using scalp electrodes. The brainwave is mainly used for diagnosis and treatment of diseases such as epilepsy, encephalitis, brain tumors and brain damage. As a result, the brainwave measurement methods and analytical methods were developed. Interface using the brainwave will not go through language or body behavior which is the result of the information processed by the brain but will pass directly to the system providing a brain-computer interface (BCI). This is possible because a variety of the brainwave appears depending on the human’s physical and mental state. Using the brainwave with the intelligent brain-computer interface or combining it with mobile devices and smart devices, regardless of space constraints, the brainwave measurement should be possible.[4,7] In this study, in order to measure the brainwave without spatial constraint, 16 channel compact brainwave measurements system using a high-speed wireless communications were designed. It was designed with a 16 channel to classify the various brainwave patterns that appear and for estimating the location of the nerve cells that triggered the brainwave. And in order to transmit the brainwave data within the channel without loss, a high-speed wireless communication must be possible that can enable a high-speed wireless transmission more sufficient than the Bluetooth, therefore, 802.11 compliant Wi-Fi communication methods were used to transfer the data to the PC. In addition, by using an analog front-end IC having a single-chip configuration with real-time digital filters, the miniaturization of the system was implemented and in order to verify the system Eye-blocking was used to observe the changes in the EEG signal. 展开更多
关键词 ELECTROENCEPHALOGRAPHY HIGH-SPEED WIRELESS transmission real-time
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Development of TaqMan-based Real-time PCR Assay for Detecting Transmissible Gastroenteritis Virus and Its Application in Vaccine Evaluation 被引量:2
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作者 俞正玉 徐向伟 +8 位作者 孙冰 何孔旺 郭容利 杜露平 温立斌 张雪寒 茅爱华 倪艳秀 李彬 《Agricultural Science & Technology》 CAS 2014年第9期1487-1490,共4页
[Objective] This study aimed to establish a TaqMan-based real-time PCR assay for detecting transmissible gastroenteritis virus (TGEV). [Method] Primers and a probe were designed according to the conserved sequence o... [Objective] This study aimed to establish a TaqMan-based real-time PCR assay for detecting transmissible gastroenteritis virus (TGEV). [Method] Primers and a probe were designed according to the conserved sequence of N gene in TGEV genome. After gradient dilution, the recombinant plasmid harboring the N gene was used as a standard for real-time PCR assay to establish the standard curve. [Re- sult] The results showed that the established real-time PCR assay exhibited a good linear relationship within the range of 102-10^10 copies/ul; the correlation coefficient was above 0.99 and the amplification efficiency ranged from 90% to 110%. The de- tection limit of real-time PCR assay for TGEV was 10 copies/μl, suggesting a high sensitivity; there was no cross reaction with other porcine viruses, indicating a good specificity; coefficients of variation within and among batches were lower than 3%, suggesting a good repeatability. The established real-time PCR method could be ap- plied in quantitative analysis and evaluation of the immune efficacy of TGEV vac- cines and detection of TGEV in clinical samples. [Conclusion] The TaqMan-based real-time PCR assay established in this study is highly sensitive and specific, which can provide technical means for the epidemiological survey of TGEV, development of TGEV vaccines and investigation of the pathogenesis of TGE. 展开更多
关键词 transmissible gastroenteritis virus (TGEV) TaqMan-based real-time PCR: Detection
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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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Remote wireless transmission and error recovery of log data
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作者 赵亦朋 李宁 王才志 《Applied Geophysics》 SCIE CSCD 2007年第4期308-312,共5页
Remote transmission of log data is an urgent problem for service companies. Remote transmission technology of log data here refers to both the transmission solution in combination with the CifNet multi-well data manag... Remote transmission of log data is an urgent problem for service companies. Remote transmission technology of log data here refers to both the transmission solution in combination with the CifNet multi-well data management system to automate the transmission, storage, management, and retrieval of log data to reduce turn-over time. It is an applied digital signature technology to implement breakpoint transmission and error recovery and ensure the effectiveness and reliability of log data transmission. 展开更多
关键词 data transmission LOG CifNet
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A Novel Secure Data Transmission Scheme in Industrial Internet of Things 被引量:26
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作者 Hongwen Hui Chengcheng Zhou +1 位作者 Shenggang Xu Fuhong Lin 《China Communications》 SCIE CSCD 2020年第1期73-88,共16页
The industrial Internet of Things(IoT)is a trend of factory development and a basic condition of intelligent factory.It is very important to ensure the security of data transmission in industrial IoT.Applying a new ch... The industrial Internet of Things(IoT)is a trend of factory development and a basic condition of intelligent factory.It is very important to ensure the security of data transmission in industrial IoT.Applying a new chaotic secure communication scheme to address the security problem of data transmission is the main contribution of this paper.The scheme is proposed and studied based on the synchronization of different-structure fractional-order chaotic systems with different order.The Lyapunov stability theory is used to prove the synchronization between the fractional-order drive system and the response system.The encryption and decryption process of the main data signals is implemented by using the n-shift encryption principle.We calculate and analyze the key space of the scheme.Numerical simulations are introduced to show the effectiveness of theoretical approach we proposed. 展开更多
关键词 industrial Internet of Things data transmission secure communication fractional-order chaotic systems
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Quality control of marine big data——a case study of real-time observation station data in Qingdao 被引量:6
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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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L2-LBMT:A Layered Load Balance Routing Protocol for Underwater Multimedia Data Transmission 被引量:2
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作者 LV Ze TANG Ruichun +2 位作者 TAO Ye SUN Xin XU Xiaowei 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第6期1018-1026,共9页
Providing highly efficient underwater transmission of mass multimedia data is challenging due to the particularities of the underwater environment. Although there are many schemes proposed to optimize the underwater a... Providing highly efficient underwater transmission of mass multimedia data is challenging due to the particularities of the underwater environment. Although there are many schemes proposed to optimize the underwater acoustic network communication protocols, from physical layer, data link layer, network layer to transport layer, the existing routing protocols for underwater wireless sensor network(UWSN) still cannot well deal with the problems in transmitting multimedia data because of the difficulties involved in high energy consumption, low transmission reliability or high transmission delay. It prevents us from applying underwater multimedia data to real-time monitoring of marine environment in practical application, especially in emergency search, rescue operation and military field. Therefore, the inefficient transmission of marine multimedia data has become a serious problem that needs to be solved urgently. In this paper, A Layered Load Balance Routing Protocol(L2-LBMT) is proposed for underwater multimedia data transmission. In L2-LBMT, we use layered and load-balance Ad Hoc Network to transmit data, and adopt segmented data reliable transfer(SDRT) protocol to improve the data transport reliability. And a 3-node variant of tornado(3-VT) code is also combined with the Ad Hoc Network to transmit little emergency data more quickly. The simulation results show that the proposed protocol can balance energy consumption of each node, effectively prolong the network lifetime and reduce transmission delay of marine multimedia data. 展开更多
关键词 UNDERWATER wireless MULTICAST multimedia data transmission load balance
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Blockchain-based data transmission control for Tactical Data Link 被引量:5
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作者 Wei Feng Yafeng Li +2 位作者 Xuetao Yang Zheng Yan Liang Chen 《Digital Communications and Networks》 SCIE CSCD 2021年第3期285-294,共10页
Tactical Data Link(TDL)is a communication system that utilizes a particular message format and a protocol to transmit data via wireless channels in an instant,automatic,and secure way.So far,TDL has shown its excellen... Tactical Data Link(TDL)is a communication system that utilizes a particular message format and a protocol to transmit data via wireless channels in an instant,automatic,and secure way.So far,TDL has shown its excellence in military applications.Current TDL adopts a distributed architecture to enhance anti-destruction capacity.However,It still faces a problem of data inconsistency and thus cannot well support cooperation across multiple militarily domains.To tackle this problem,we propose to leverage blockchain to build an automatic and adaptive data transmission control scheme for TDL.It achieves automatic data transmission and realizes information consistency among different TDL entities.Besides,applying smart contracts based on blockchain further enables adjusting data transmission policies automatically.Security analysis and experimental results based on simulations illustrate the effectiveness and efficiency of our proposed scheme. 展开更多
关键词 Blockchain Tactical data link CONSENSUS data transmission control
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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 Intelligent Diagnosis of Co-frequency Vibration Faults in Rotating Machinery Based on Lightweight-Convolutional Neural Networks
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作者 Xin Pan Xiancheng Zhang +1 位作者 Zhinong Jiang Guangfu Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期264-282,共19页
The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the... The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the equipment.In engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively time-consuming.Therefore,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault diagnosis.The critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation method.Based on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is realized.Moreover,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault diagnosis.It is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance. 展开更多
关键词 Co-frequency vibration real-time diagnosis LW-CNN data augmentation
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Power Line Monitoring Data Transmission Using Wireless Sensor Network 被引量:4
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作者 Lifen Li Huaiyu Zhao 《Journal of Power and Energy Engineering》 2015年第8期83-88,共6页
The WSN used in power line monitoring is long chain structure, and the bottleneck near the Sink node is more obvious. In view of this, A Sink nodes’ cooperation mechanism is presented. The Sink nodes from different W... The WSN used in power line monitoring is long chain structure, and the bottleneck near the Sink node is more obvious. In view of this, A Sink nodes’ cooperation mechanism is presented. The Sink nodes from different WSNs are adjacently deployed. Adopting multimode and spatial multiplexing network technology, the network is constructed into multi-mode-level to achieve different levels of data streaming. The network loads are shunted and the network resources are rationally utilized. Through the multi-sink nodes cooperation, the bottlenecks at the Sink node and its near several jump nodes are solved and process the competition of communication between nodes by channel adjustment. Finally, the paper analyzed the method and provided simulation experiment results. Simulation results show that the method can solve the funnel effect of the sink node, and get a good QoS. 展开更多
关键词 WIRELESS Sensor NETWORK (WSN) Power Line Monitoring data transmission MULTIMODE NETWORK
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Enhanced Data Transmission Rate of XCTD Profiler Based on OFDM 被引量:1
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作者 LI Hongzhi ZHANG Sai +2 位作者 QIN Xiaocong ZHANG Xiaoyang ZHENG Yu 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第5期1079-1085,共7页
An expendable conductivity-temperature-depth profiler(XCTD)is one of the most important instruments used to obtain hydrological data,such as temperature and conductivity,and detect ocean depth in a large area.However,... An expendable conductivity-temperature-depth profiler(XCTD)is one of the most important instruments used to obtain hydrological data,such as temperature and conductivity,and detect ocean depth in a large area.However,the XCTD channel provides poor time-varying performance,narrowband,and low signal-to-noise ratio(SNR),which severely restricts the data transmission rate.In contrast to conventional single-carrier modulation techniques,such as amplitude-shift keying and differential phase-shift keying,this article provides a new method,based on orthogonal frequency division multiplexing(OFDM)to enhance the data transmission rate of deep-sea abandoned profilers.We apply the OFDM to enhance the SNR of the XCTD,which is achieved by reducing the data transmission rate of each sub-channel.Moreover,the bandwidth utilization may be improved by increasing the number of subcarriers in a given bandwidth,which enhances the data transmission rate.Based on analysis of the XCTD channel model,OFDM with different parameters such as constellation mapping,number of subcarriers,subcarrier spacing,signal period and cyclic prefix are achieved.To verify the effectiveness of the OFDM,this study investigates the influence of different parameters on the data transmission rate at different noise levels,i.e.,-20 dB and-40 d B. 展开更多
关键词 XCTD OFDM SUBCARRIER BANDWIDTH UTILIZATION data transmission RATE
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Fast Web - Based Data Transmission 被引量:2
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作者 Wei Zukuan Department of Computer Science & Engineering, Inha University, Inchon 402 751, Korea Kim Jaehong Department of Computer Science, Youngdong University, Youngdong, Korea Bae Haeyoung Department of Computer Science & Engineering, Inha Uni 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期165-176,共12页
Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient metho... Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient methods for this purpose: division transmission and progressive transmission methods. In division transmission method, a map can be divided into several parts, called “tiles”, and only tiles can be transmitted at the request of a client. In progressive transmission method, a map can be split into several phase views based on the significance of vertices, and a server produces a target object and then transmits it progressively when this spatial object is requested from a client. In order to achieve these methods, the algorithms, “tile division”, “priority order estimation” and the strategies for data transmission are proposed in this paper, respectively. Compared with such traditional methods as “map total transmission” and “layer transmission”, the web based GIS data transmission, proposed in this paper, is advantageous in the increase of the data transmission efficiency by a great margin. 展开更多
关键词 spatial data transmission spatial query processing web based GIS geographic information system spatial database.
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Energy Efficiency Based on Joint Data Packet Fragmentation and Cooperative Transmission 被引量:3
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作者 ZHANG Zufan YI Yinxue YANG Jing JING Xiaorong 《China Communications》 SCIE CSCD 2014年第10期96-105,共10页
Energy efficiency(EE) is a key requirement for the design of short-range communication network.In order to alleviate energy consumption(EC) constraint,a novel layered heterogeneous mobile cloud architecture is propose... Energy efficiency(EE) is a key requirement for the design of short-range communication network.In order to alleviate energy consumption(EC) constraint,a novel layered heterogeneous mobile cloud architecture is proposed in this paper.Based on the proposed layered heterogeneous mobile cloud architecture,we establish an appropriate energy consumption model,and design an energy efficiency scheme based on joint data packet fragmentation and cooperative transmission and analyze the energy efficiency corresponding to different packet sizes and the cloud size.Simulation results show that,when all nodes of the cloud are accessing the same size of data packet fragmentation,the proposed layered heterogeneous mobile cloud architecture can provide significant energy savings.The results provide useful insights into the possible operation of the strategies and show that significant energy consumption reductions are possible. 展开更多
关键词 layered heterogeneous mobilecloud energy efficiency data packetfragmentation cooperative transmission
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