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Identification and evaluation of shale oil micromigration and its petroleum geological significance 被引量:2
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作者 HU Tao JIANG Fujie +10 位作者 PANG Xiongqi LIU Yuan WU Guanyun ZHOU Kuo XIAO Huiyi JIANG Zhenxue LI Maowen JIANG Shu HUANG Liliang CHEN Dongxia MENG Qingyang 《Petroleum Exploration and Development》 SCIE 2024年第1期127-140,共14页
Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil... Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil micro-migration phenomenon.The hydrocarbon micro-migration in shale oil was quantitatively evaluated and verified by a self-created hydrocarbon expulsion potential method,and the petroleum geological significance of shale oil micro-migration evaluation was determined.Results show that significant micro-migration can be recognized between the organic-rich lamina and organic-poor lamina.The organic-rich lamina has strong hydrocarbon generation ability.The heavy components of hydrocarbon preferentially retained by kerogen swelling or adsorption,while the light components of hydrocarbon were migrated and accumulated to the interbedded felsic or carbonate organic-poor laminae as free oil.About 69% of the Fengcheng Formation shale samples in Well MY1 exhibit hydrocarbon charging phenomenon,while 31% of those exhibit hydrocarbon expulsion phenomenon.The reliability of the micro-migration evaluation results was verified by combining the group components based on the geochromatography effect,two-dimension nuclear magnetic resonance analysis,and the geochemical behavior of inorganic manganese elements in the process of hydrocarbon migration.Micro-migration is a bridge connecting the hydrocarbon accumulation elements in shale formations,which reflects the whole process of shale oil generation,expulsion and accumulation,and controls the content and composition of shale oil.The identification and evaluation of shale oil micro-migration will provide new perspectives for dynamically differential enrichment mechanism of shale oil and establishing a“multi-peak model in oil generation”of shale. 展开更多
关键词 shale oil micro-migration identification micro-migration evaluation Junggar Basin Mahu Sag Lower Permian Fengcheng Formation hydrocarbon expulsion potential method
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Adversarial attacks and defenses for digital communication signals identification
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作者 Qiao Tian Sicheng Zhang +1 位作者 Shiwen Mao Yun Lin 《Digital Communications and Networks》 SCIE CSCD 2024年第3期756-764,共9页
As modern communication technology advances apace,the digital communication signals identification plays an important role in cognitive radio networks,the communication monitoring and management systems.AI has become ... As modern communication technology advances apace,the digital communication signals identification plays an important role in cognitive radio networks,the communication monitoring and management systems.AI has become a promising solution to this problem due to its powerful modeling capability,which has become a consensus in academia and industry.However,because of the data-dependence and inexplicability of AI models and the openness of electromagnetic space,the physical layer digital communication signals identification model is threatened by adversarial attacks.Adversarial examples pose a common threat to AI models,where well-designed and slight perturbations added to input data can cause wrong results.Therefore,the security of AI models for the digital communication signals identification is the premise of its efficient and credible applications.In this paper,we first launch adversarial attacks on the end-to-end AI model for automatic modulation classifi-cation,and then we explain and present three defense mechanisms based on the adversarial principle.Next we present more detailed adversarial indicators to evaluate attack and defense behavior.Finally,a demonstration verification system is developed to show that the adversarial attack is a real threat to the digital communication signals identification model,which should be paid more attention in future research. 展开更多
关键词 Digital communication signals identification AI model Adversarial attacks Adversarial defenses Adversarial indicators
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A YOLOv8-CE-based real-time traffic sign detection and identification method for autonomous vehicles
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作者 Yuechen Luo Yusheng Ci +1 位作者 Hexin Zhang Lina Wu 《Digital Transportation and Safety》 2024年第3期82-91,共10页
Traffic sign detection in real scenarios is challenging due to their complexity and small size,often preventing existing deep learning models from achieving both high accuracy and real-time performance.An improved YOL... Traffic sign detection in real scenarios is challenging due to their complexity and small size,often preventing existing deep learning models from achieving both high accuracy and real-time performance.An improved YOLOv8 model for traffic sign detection is proposed.Firstly,by adding Coordinate Attention(CA)to the Backbone,the model gains location information,improving detection accuracy.Secondly,we also introduce EIoU to the localization function to address the ambiguity in aspect ratio descriptions by calculating the width-height difference based on CIoU.Additionally,Focal Loss is incorporated to balance sample difficulty,enhancing regression accuracy.Finally,the model,YOLOv8-CE(YOLOv8-Coordinate Attention-EIoU),is tested on the Jetson Nano,achieving real-time street scene detection and outperforming the Raspberry Pi 4B.Experimental results show that YOLOv8-CE excels in various complex scenarios,improving mAP by 2.8%over the original YOLOv8.The model size and computational effort remain similar,with the Jetson Nano achieving an inference time of 96 ms,significantly faster than the Raspberry Pi 4B. 展开更多
关键词 YOLOv8-CE-based REAL-TIME Traffic signS Detection
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Advancing healthcare through laboratory on a chip technology:Transforming microorganism identification and diagnostics
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作者 Carlos M Ardila 《World Journal of Clinical Cases》 SCIE 2025年第3期9-19,共11页
In a recent case report in the World Journal of Clinical Cases,emphasized the crucial role of rapidly and accurately identifying pathogens to optimize patient treatment outcomes.Laboratory-on-a-chip(LOC)technology has... In a recent case report in the World Journal of Clinical Cases,emphasized the crucial role of rapidly and accurately identifying pathogens to optimize patient treatment outcomes.Laboratory-on-a-chip(LOC)technology has emerged as a transformative tool in health care,offering rapid,sensitive,and specific identification of microorganisms.This editorial provides a comprehensive overview of LOC technology,highlighting its principles,advantages,applications,challenges,and future directions.Success studies from the field have demonstrated the practical benefits of LOC devices in clinical diagnostics,epidemiology,and food safety.Comparative studies have underscored the superiority of LOC technology over traditional methods,showcasing improvements in speed,accuracy,and portability.The future integration of LOC with biosensors,artificial intelligence,and data analytics promises further innovation and expansion.This call to action emphasizes the importance of continued research,investment,and adoption to realize the full potential of LOC technology in improving healthcare outcomes worldwide. 展开更多
关键词 Laboratory-on-a-chip Microorganism identification DIAGNOSTICS Point-ofcare testing Biosensors
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Identification Signs and Prospects of Hydrate Gas
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作者 徐振中 陈世悦 +1 位作者 杨淑卿 马在田 《Marine Science Bulletin》 CAS 2007年第1期84-96,共13页
Gas hydrate is a kind of icy crystal body formed by water and natural gas in special conditions. The discovery of gas hydrates provides a wide sphere and a new way of thinking for finding clean and effective energy re... Gas hydrate is a kind of icy crystal body formed by water and natural gas in special conditions. The discovery of gas hydrates provides a wide sphere and a new way of thinking for finding clean and effective energy resources to replace increasingly exhausted traditional energy resources. Moreover, in our country there are a wide realm and bright prospect in the exploration of gas hydrate. This paper has summarized the progress on the study of gas hydrate. And based on the former research about gas hydrates, the integrative identification signs of gas hydrates were summarized in the aspects of seismic data, geophysical well logging, sedimentary and rock, geochemistry, topography and morphology. In the end, the author hopes it may provide some useful clues to the exploration of gas hydrate. 展开更多
关键词 integrative identification signs gas hydrate exploration
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Risk identification and regulatory system design for the carbon market 被引量:4
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作者 Tao Wang Wentao Wang 《Chinese Journal of Population,Resources and Environment》 2016年第2期59-67,共9页
Currently,the global carbon trading systems are fragmented and belong to different governments or are under the jurisdiction of different regions,resulting in a series of new problems,such as how to link dispersed tra... Currently,the global carbon trading systems are fragmented and belong to different governments or are under the jurisdiction of different regions,resulting in a series of new problems,such as how to link dispersed trading systems,how to compare the emission reduction of various markets and other issues.Since the development of the international carbon market is relatively immature with uncertain life expectancy and volatility during its short history,and there is a lack of quantitative data on the long-term record,the market could provide few risk management tools.Meanwhile,with the launches of China's regional carbon trading pilots in seven provinces since 2013 and combined with the national voluntary emission trading system,carbon trading will become an important mechanism for China in achieving its emission reduction target.In the first stage,the carbon finance market is at least faced with mechanism design risks,market supply risks and compliance risks.Therefore,to secure the development of the carbon market and for public interest,relevant government departments of China should identify the risks facing the market and should make the basic principles and goals,such as ensuring effective trading and pricing mechanisms to avoid fraud and price manipulation,and balancing transparency and confidentiality of information.Consequently,the governments should develop a comprehensive carbon finance regulatory system covering regulatory legislation,regulatory institutions and their authorities,regulatory scope as well as regulatory objects. 展开更多
关键词 Carbon market risks identification regulatory system
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New Individual Identification Method of Radiation Source Signal Based on Entropy Feature and SVM 被引量:5
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作者 Yun Lin Xiao-Chun Xu Zi-Cheng Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第1期98-101,共4页
In this paper,according to the defect of methods which have low identification rate in low SNR,a new individual identification method of radiation source based on information entropy feature and SVM is presented. Firs... In this paper,according to the defect of methods which have low identification rate in low SNR,a new individual identification method of radiation source based on information entropy feature and SVM is presented. Firstly,based on the theory of multi-resolution wavelet analysis,the wavelet power spectrum of noncooperative signal can be gotten. Secondly,according to the information entropy theory,the wavelet power spectrum entropy is defined in this paper. Therefore,the database of signal's wavelet power spectrum entropy can be built in different SNR and signal parameters. Finally,the sorting and identification model based on SVM is built for the individual identification of radiation source signal. The simulation result indicates that this method has a high individual's identification rate in low SNR,when the SNR is greater than 4 dB,the identification rate can reach 100%. Under unstable SNR conditions,when the range of SNR is between 0 dB and 24 dB,the average identification rate is more than 92. 67%. Therefore,this method has a great application value in the complex electromagnetic environment. 展开更多
关键词 RADIATION source INDIVIDUAL identification WAVELET power spectrum information ENTROPY support VECTOR machine
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Species-specific COI primers for rapid identification of a globally significant invasive pest, the cassava mealybug Phenacoccus manihoti Matile-Ferrero 被引量:3
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作者 WANG Yu-sheng TIAN Hu +1 位作者 WAN Fang-hao ZHANG Gui-fen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第5期1042-1049,共8页
The globally invasive cassava mealybug Phenacoccus manihoti Matile-Ferrero is a pernicious pest of cassava,and its recent introduction into Asia has raised considerable alarm.To slow or prevent further invasion,an acc... The globally invasive cassava mealybug Phenacoccus manihoti Matile-Ferrero is a pernicious pest of cassava,and its recent introduction into Asia has raised considerable alarm.To slow or prevent further invasion,an accurate,simple,and developmental-stage-independent detection method for P.manihoti is required.In the present study,a PCR method based on a species-specific mitochondrial DNA cytochrome oxidase I(SS-COI)marker was developed for rapid identification of P.manihoti.One pair of SS-COI primers(PMSSZW-1F and PMSSZW-1R)was designed based on sequence variations in the COI gene among P.manihoti and related mealybug species.Specificity of the primer pair was validated on 21 closely related species.Sensitivity tests were performed on four immature developmental stages and female adults.Efficacy tests demonstrated that at the relatively low concentration of(135.2±14.7)pgresuspended DNA,the specific fragment was detected in all replicates.Furthermore,the SS-COI primer pair was assayed on three populations of P.manihoti from major exporting countries of cassava.The PCR assay was proved to be a rapid,simple,and reliable molecular measure for the identification of P.manihoti.This tool will be useful for quarantine,monitoring,and management of this invasive pest. 展开更多
关键词 Phenacoccus manihoti CASSAVA MEALYBUG INVASIVE pest molecular identification SPECIES-SPECIFIC COI PRIMERS
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Wood species identification using spectral reflectance feature and optimal illumination radian design 被引量:3
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作者 Peng Zhao Jun Cao 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第1期219-224,共6页
We developed a scheme based on wood surface novel wood recognition spectral features that aimed to solve three problems. First was elimination of noise in some bands of wood spectral reflection curves. Second was imp... We developed a scheme based on wood surface novel wood recognition spectral features that aimed to solve three problems. First was elimination of noise in some bands of wood spectral reflection curves. Second was improvement of wood feature selection based on analysis of wood spectral data. The wood spectral band is 350-2500 nm, a 2150D vector with a spectral sampling interval of 1 nm. We developed a feature selection proce- dure and a filtering procedure by solving the eigenvalues of the dispersion matrix. Third, we optimized the design for the indoor radian's mounting height. We used a genetic algorithm to solve the optimal radian's height so that the spectral reflection curves had the best classification infor- mation for wood species. Experiments on fivecommon wood species in northeast China showed overall recogni- tion accuracy 〉95 % at optimal recognition velocity. 展开更多
关键词 Wood species identification FEATURESELECTION Radian Genetic algorithm Spectral analysis
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The Identification of Frequency Hopping Signal Using Compressive Sensing 被引量:3
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作者 Jia YUAN Pengwu TIAN Hongyi YU 《Communications and Network》 2009年第1期52-56,共5页
Compressive sensing (CS) creates a new framework of signal reconstruction or approximation from a smaller set of incoherent projection compared with the traditional Nyquist-rate sampling theory. Recently, it has been ... Compressive sensing (CS) creates a new framework of signal reconstruction or approximation from a smaller set of incoherent projection compared with the traditional Nyquist-rate sampling theory. Recently, it has been shown that CS can solve some signal processing problems given incoherent measurements without ever reconstructing the signals. Moreover, the number of measurements necessary for most compressive signal processing application such as detection, estimation and classification is lower than that necessary for signal reconstruction. Based on CS, this paper presents a novel identification algorithm of frequency hopping (FH) signals. Given the hop interval, the FH signals can be identified and the hopping frequencies can be estimated with a tiny number of measurements. Simulation results demonstrate that the method is effective and efficient. 展开更多
关键词 COMPRESSIVE SENSING frequency HOPPING signAL identification
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Identification of Contaminant Source Characteristics and Monitoring Network Design in Groundwater Aquifers: An Overview 被引量:3
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作者 Mahsa Amirabdollahian Bithin Datta 《Journal of Environmental Protection》 2013年第5期26-41,共16页
The groundwater system is often polluted by different sources of contamination where the sources are difficult to detect. The presence of contamination in groundwater poses significant challenges to its delineation an... The groundwater system is often polluted by different sources of contamination where the sources are difficult to detect. The presence of contamination in groundwater poses significant challenges to its delineation and quantification. The remediation of a contaminated site requires an optimal decision making system to identify the pollutant source characteristics accurately and efficiently. The source characteristics are generally identified using contaminant concentration measurements from arbitrary or planned monitoring locations. To effectively characterize the sources of pollution, the monitoring locations should be selected appropriately. An efficient monitoring network will result in satisfactory characterization of contaminant sources. On the other hand, an appropriate design of monitoring network requires reliable source characteristics. A coupled iterative sequential source identification and dynamic monitoring network design, improves substantially the accuracy of source identification model. This paper reviews different source identification and monitoring network design methods in groundwater contaminant sites. Further, the models for sequential integration of these two models are presented. The effective integration of source identification and dedicated monitoring network design models, distributed sources, parameter uncertainty, and pollutant geo-chemistry are some of the issues which need to be addressed in efficient, accurate and widely applicable methodologies for identification of unknown pollutant sources in contaminated aquifers. 展开更多
关键词 POLLUTION Detection AQUIFER CONTAMINATION GROUNDWATER Source identification MONITORING Network Design
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Application of orthogonal experimental design and Tikhonov regularization method for the identification of parameters in the casting solidification process 被引量:4
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作者 Dashan SUI Zhenshan CUI 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第1期13-21,共9页
The inverse heat conduction method is one of methods to identify the casting simulation parameters. A new inverse method was presented according to the Tikhonov regularization theory. One appropriate regularized funct... The inverse heat conduction method is one of methods to identify the casting simulation parameters. A new inverse method was presented according to the Tikhonov regularization theory. One appropriate regularized functional was established, and the functional was solved by the sensitivity coefficient and Newtonaphson iteration method. Moreover, the orthogonal experimental design was used to estimate the appropriate initial value and variation domain of each variable to decrease the number of iteration and improve the identification accuracy and efficiency. It illustrated a detailed case of AlSiTMg sand mold casting and the temperature measurement experiment was done. The physical properties of sand mold and the interracial heat transfer coefficient were identified at the meantime. The results indicated that the new regularization method was efficient in overcoming the ill-posedness of the inverse heat conduction problem and improving the stability and accuracy of the solutions. 展开更多
关键词 Orthogonal experimental design Regularization method Parameters identification Numerical simulation
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An input signal used in process identification - chaos sequence 被引量:1
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作者 GengZhao DelingZheng ShaojunHuang 《Journal of University of Science and Technology Beijing》 CSCD 2004年第2期183-186,共4页
The sequences which consist of any segment of a chaos sequence are called asC-sequences. These sequences could be used as a kind of input signals to replace M-sequences in theprocess identification. This substitution ... The sequences which consist of any segment of a chaos sequence are called asC-sequences. These sequences could be used as a kind of input signals to replace M-sequences in theprocess identification. This substitution is theoretically proved to be feasible. InverseC-sequences are created in a way similar to inverse M-sequences to solve the problem thatC-sequences have non-ideal balance property, that is, the numbers of '0' and '1' are unequal.Besides its good pseudo-random property, the sequences have other advantages such as easy togenerate, varieties of the segment and adjustable cycle time. 展开更多
关键词 process identification M-SEQUENCE C-sequence
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Electronic Throttle Control System: Modeling, Identification and Model-Based Control Designs 被引量:4
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作者 Robert N. K. Loh Witt Thanom +1 位作者 Jan S. Pyko Anson Lee 《Engineering(科研)》 2013年第7期587-600,共14页
Electronic throttle control (ETC) system has worked its way to becoming a standard subsystem in most of the current automobiles as it has contributed much to the improvement of fuel economy, emissions, drivability and... Electronic throttle control (ETC) system has worked its way to becoming a standard subsystem in most of the current automobiles as it has contributed much to the improvement of fuel economy, emissions, drivability and safety. Precision control of the subsystem, which consists of a dc motor driving a throttle plate, a pre-loaded return spring and a set of gear train to regulate airflow into the engine, seems rather straightforward and yet complex. The difficulties lie in the unknown system parameters, hard nonlinearity of the pre-loaded spring that pulls the throttle plate to its default position, and friction, among others. In this paper, we extend our previous results obtained for the modeling, unknown system parameters identification and control of a commercially available Bosch’s DV-E5 ETC system. Details of modeling and parameters identification based on laboratory experiments, data analysis, and knowledge of the system are provided. The parameters identification results were verified and validated by a real-time PID control implemented with an xPC Target. A nonlinear control design was then proposed utilizing the input-output feedback linearization approach and technique. In view of a recent massive auto recalls due to the controversial uncontrollable engine accelerations, the results of this paper may inspire further research interest on the drive-by-wire technology. 展开更多
关键词 ETC SYSTEM SYSTEM identification Nonlinear CONTROL INPUT-OUTPUT Feedback LINEARIZATION XPC Target-Based CONTROL SYSTEM
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Genome-wide identification and expression analysis of NIN-like Protein(NLP)genes reveals their potential roles in the response to nitrate signaling in watermelon 被引量:2
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作者 Gaopeng Yuan Dexi Sun +5 位作者 Yifan Wang Guolin An Weihua Li Wenjing Si Junpu Liu Yingchun Zhu 《Horticultural Plant Journal》 SCIE CAS CSCD 2022年第5期602-614,共13页
To balance the relationship between high yield and low nitrogen supply,the nitrogen utilization efficiency of watermelon needs to be improved urgently.Nodule inception-like Protein(NLP)transcription factors play a key... To balance the relationship between high yield and low nitrogen supply,the nitrogen utilization efficiency of watermelon needs to be improved urgently.Nodule inception-like Protein(NLP)transcription factors play a key node role in nitrate response and growth and development of plant,however,comprehensive analysis of the NLP gene family in watermelon is unclear.This study explored the functional classification,evolutionary characteristics,and expression profile of the ClNLP gene family.Three ClNLPs were categorized into three groups according to their gene structure and phylogeny.All of them contained the conserved RWP-RK and PB1 domains.Evolutionary analysis of ClNLPs revealed that ClNLP1 and ClNLP3 underwent strong purified selection.In addition,cis-acting elements related to plant hormones and abiotic stresses were present in the ClNLP promoter.According to tissue-specific analysis ClNLP was widely expressed in roots,stems,leaves,flowers and fruits,and ClNLP1 was significantly induced in the roots of different nitrogen utilization varieties under different nitrate nitrogen supply.The SRTING functional protein association network suggested that ClNLP1 is associated with most genes,such as NRT1.1,NRT2.1,NIA1,and NIR1,and the dual-luciferase reporter assay found that ClNLP1 positively regulates the expression of ClNRT2.1.We speculated that ClNLP1 might play a central role in regulating the response of watermelon to nitrate nitrogen. 展开更多
关键词 Genome-wide identification NLP Nitrate signaling Nitrate nitrogen WATERMELON
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Deep learning-based LPI radar signals analysis and identification using a Nyquist Folding Receiver architecture 被引量:2
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作者 Tao Wan Kai-li Jiang +1 位作者 Hao Ji Bin Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期196-209,共14页
Nyquist Folding Receiver(NYFR)is a perceptron structure that realizes a low probability of intercept(LPI)signal analog to information.Aiming at the problem of LPI radar signal receiving,the time domain,frequency domai... Nyquist Folding Receiver(NYFR)is a perceptron structure that realizes a low probability of intercept(LPI)signal analog to information.Aiming at the problem of LPI radar signal receiving,the time domain,frequency domain,and time-frequency domain problems of signals intercepted by NYFR structure are studied.Combined with the time-frequency analysis(TFA)method,a radar recognition scheme based on deep learning(DL)is introduced,which can reliably classify common LPI radar signals.First,the structure of NYFR and its characteristics in the time domain,frequency domain,and time and frequency domain are analyzed.Then,the received signal is then converted into a time-frequency image(TFI).Finally,four kinds of DL algorithms are used to classify LPI radar signals.Simulation results demonstrate the correctness of the NYFR structure,and the effectiveness of the proposed recognition method is verified by comparison experiments. 展开更多
关键词 Nyquist folding receiver ULTRA-WIDEBAND Deep learning Time-frequency analysis identification Classification
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A model for automatic identification of human pulse signals 被引量:2
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作者 Hui-yan WANG Pei-yong ZHANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第10期1382-1389,共8页
This paper presents a quantitative method for automatic identification of human pulse signals. The idea is to start with the extraction of characteristic parameters and then to construct the recognition model based on... This paper presents a quantitative method for automatic identification of human pulse signals. The idea is to start with the extraction of characteristic parameters and then to construct the recognition model based on Bayesian networks. To identify depth, frequency and rhythm, several parameters are proposed. To distinguish the strength and shape, which cannot be represented by one or several parameters and are hard to recognize, the main time-domain feature parameters are computed based on the feature points of the pulse signal. Then the extracted parameters are taken as the input and five models for automatic pulse signal identification are constructed based on Bayesian networks. Experimental results demonstrate that the method is feasible and effective in recognizing depth, frequency, rhythm, strength and shape of pulse signals, which can be expected to facilitate the modernization of pulse diagnosis. 展开更多
关键词 Pulse signal identification Feature extraction Bayesian network Quantitative diagnosis Wavelet transform
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Parameter identification of inertially stabilized platforms using current command design 被引量:2
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作者 黎志强 张智永 +1 位作者 周擎坤 范大鹏 《Journal of Central South University》 SCIE EI CAS 2013年第2期342-353,共12页
Accurate parameter identification is essential when designing controllers for inertially stabilized platforms (lSPs). But traditional identification methods suffer from observation measurement noise and operating re... Accurate parameter identification is essential when designing controllers for inertially stabilized platforms (lSPs). But traditional identification methods suffer from observation measurement noise and operating restrictions of ISPs. To address this issue, a novel identification method based on current command design and multilevel coordinate search (MCS) algorithm without any higher order measurement differentiations was proposed. The designed current commands were adopted to obtain parameter decoupled models with the platform operating under allowable conditions. MCS algorithm was employed to estimate the parameters based on parameter decoupled models. A comparison experiment between the proposed method and non-linear least square method was carried out and most of the relative errors of identified parameters obtained by the proposed method were below 10%. Simulation and experiment based on identified parameters were conducted. A velocity control structure was also developed with disturbance observer (DOB) for application in disturbance compensation control system of an ISR Experimental results show that the control scheme based on the identified parameters with DOB has the best disturbance rejection performance. It reduces the peak to peak value (PPV) of velocity error integral to 0.8 mrad which is much smaller than the value (10 mrad) obtained by the single velocity controller without DOB. Compared with the control scheme based on sweep model with DOB compensation, the proposed control scheme improves the PPV of velocity error integral by 1.625 times. 展开更多
关键词 parameter identification current command design multilevel coordinate search inertially stabilized platforms
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Development and Testing of an Automatic Turning Movement Identification System at Signalized Intersections 被引量:1
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作者 Kun Xu Ping Yi +1 位作者 Chun Shao Jialei Mao 《Journal of Transportation Technologies》 2013年第4期241-246,共6页
Vehicle turning movement data from signalized intersections is utilized for numerous applications in the field of transportation. Such applications include real-time adaptive signal control, dynamic traffic assignment... Vehicle turning movement data from signalized intersections is utilized for numerous applications in the field of transportation. Such applications include real-time adaptive signal control, dynamic traffic assignment, and traffic demand estimation. However, it is very time consuming and costly to obtain vehicle turning movement information manually. Previous efforts to simplify this process were focused on solving the problem using an O-D matrix, but this method proved to be inaccurate and unreliable with the existing data acquisition system. Another study involved the identification of vehicle turning movements from the detector information, but the presence of shared lanes led to uncertainties in vehicle matching, thus limiting application of the method only to intersections without shared lanes. In light of those unsuccessful attempts, this paper develops and tests a system called the Automatic Turning Movement Identification System (ATMIS), which estimates vehicle turning movements at a signalized intersection in real time, regardless of its geometry. The results from lab experiments as well as a field test show that the algorithm is very promising and may potentially be expanded for field applications. 展开更多
关键词 TURNING MOVEMENT identification signalized INTERSECTION DETECTOR and Detection Vehicle MATCHING LAB Experiment and Field Test
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An Optimized Convolutional Neural Network with Combination Blocks for Chinese Sign Language Identification 被引量:1
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作者 Yalan Gao Yanqiong Zhang Xianwei Jiang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第7期95-117,共23页
(Aim)Chinese sign language is an essential tool for hearing-impaired to live,learn and communicate in deaf communities.Moreover,Chinese sign language plays a significant role in speech therapy and rehabilitation.Chine... (Aim)Chinese sign language is an essential tool for hearing-impaired to live,learn and communicate in deaf communities.Moreover,Chinese sign language plays a significant role in speech therapy and rehabilitation.Chinese sign language identification can provide convenience for those hearing impaired people and eliminate the communication barrier between the deaf community and the rest of society.Similar to the research of many biomedical image processing(such as automatic chest radiograph processing,diagnosis of chest radiological images,etc.),with the rapid development of artificial intelligence,especially deep learning technologies and algorithms,sign language image recognition ushered in the spring.This study aims to propose a novel sign language image recognition method based on an optimized convolutional neural network.(Method)Three different combinations of blocks:Conv-BN-ReLU-Pooling,Conv-BN-ReLU,Conv-BN-ReLU-BN were employed,including some advanced technologies such as batch normalization,dropout,and Leaky ReLU.We proposed an optimized convolutional neural network to identify 1320 sign language images,which was called as CNN-CB method.Totally ten runs were implemented with the hold-out randomly set for each run.(Results)The results indicate that our CNN-CB method gained an overall accuracy of 94.88±0.99%.(Conclusion)Our CNN-CB method is superior to thirteen state-of-the-art methods:eight traditional machine learning approaches and five modern convolutional neural network approaches. 展开更多
关键词 Convolutional neural network combination blocks Chinese sign language batch normalization DROPOUT Leaky ReLU M-fold cross-validation
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