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Intrusion detection using rough set classification 被引量:16
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作者 张连华 张冠华 +2 位作者 郁郎 张洁 白英彩 《Journal of Zhejiang University Science》 EI CSCD 2004年第9期1076-1086,共11页
Recently machine learning-based intrusion detection approaches have been subjected to extensive researches because they can detect both misuse and anomaly. In this paper, rough set classification (RSC), a modern learn... Recently machine learning-based intrusion detection approaches have been subjected to extensive researches because they can detect both misuse and anomaly. In this paper, rough set classification (RSC), a modern learning algorithm, is used to rank the features extracted for detecting intrusions and generate intrusion detection models. Feature ranking is a very critical step when building the model. RSC performs feature ranking before generating rules, and converts the feature ranking to minimal hitting set problem addressed by using genetic algorithm (GA). This is done in classical approaches using Support Vector Machine (SVM) by executing many iterations, each of which removes one useless feature. Compared with those methods, our method can avoid many iterations. In addition, a hybrid genetic algorithm is proposed to increase the convergence speed and decrease the training time of RSC. The models generated by RSC take the form of'IF-THEN' rules, which have the advantage of explication. Tests and comparison of RSC with SVM on DARPA benchmark data showed that for Probe and DoS attacks both RSC and SVM yielded highly accurate results (greater than 99% accuracy on testing set). 展开更多
关键词 Intrusion detection Rough set classification Support vector machine Genetic algorithm
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Robust adaptive fuzzy control for a class of perturbed pure-feedback nonlinear systems 被引量:4
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作者 JianjiangYU TianpingZHANG HaijunGU 《控制理论与应用(英文版)》 EI 2004年第2期175-178,共4页
A new design scheme of direct adaptive fuzzy controller for a class of perturbed pure-feedback nonlinear systems is proposed. The design is based on backstepping and the approximation capability of the first type fuzz... A new design scheme of direct adaptive fuzzy controller for a class of perturbed pure-feedback nonlinear systems is proposed. The design is based on backstepping and the approximation capability of the first type fuzzy systems. A continuous robust term is adopted to minify the influence of modeling errors or disturbances. By introducing the modified integral-type Lyapunov function, the approach is able to avoid the requirement of the upper bound of the first time derivation of the high frequency control gain. Through theoretical analysis, the closed-loop control system is proven to be semi-globally uniformly ultimately bounded, with tracking error converging to a residual set. 展开更多
关键词 Pure-feedback nonlinear system BACKSTEPPING Fuzzy control Robustness
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Approach for workflow modeling using π-calculus 被引量:5
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作者 杨东 张申生 《Journal of Zhejiang University Science》 EI CSCD 2003年第6期643-650,共8页
As a variant of process algebra, π calculus can describe the interactions between evolving processes. By modeling activity as a process interacting with other processes through ports, this paper presents a new appro... As a variant of process algebra, π calculus can describe the interactions between evolving processes. By modeling activity as a process interacting with other processes through ports, this paper presents a new approach: representing workflow models using π calculus. As a result, the model can characterize the dynamic behaviors of the workflow process in terms of the LTS (Labeled Transition Semantics) semantics of π calculus. The main advantage of the workflow model's formal semantic is that it allows for verification of the model's properties, such as deadlock free and normal termination. Moreover, the equivalence of workflow models can be checked through weak bisimulation theorem in the π calculus, thus facilitating the optimization of business processes. 展开更多
关键词 Workflow modeling π calculus Business process modeling
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Thermal Decomposition Mechanism and Non Isothermal Kinetics of Complex of [La_2(P-MBA)_6(PHEN)_2]2H_2O 被引量:3
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作者 张建军 王瑞芬 +1 位作者 白继海 王淑萍 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期449-452,共4页
The complex of [La 2(P MBA) 6(PHEN) 2]2H 2O (P MBA: p methylbenzoate and PHEN: 1,10 phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [La 2(P M... The complex of [La 2(P MBA) 6(PHEN) 2]2H 2O (P MBA: p methylbenzoate and PHEN: 1,10 phenanthroline) was prepared and characterized by elemental analysis and IR spectroscopy. The thermal behavior of [La 2(P MBA) 6(PHEN) 2]2H 2O in dynamic nitrogen atmosphere was investigated by TG DTG techniques. The results show that the thermal decomposition process of the [La 2(P MBA) 6(PHEN) 2]2H 2O occurs in five steps. The empirical kinetic model for the first step thermal decomposition obtained by Malek method is SB(m,n). The activation energy E and the pre exponential factor lnA for this step reaction are 76.4 kJ·mol -1 and 24.92, respectively. 展开更多
关键词 rare earths lanthanum complex non isothermal kinetics P methylbenzoic acid thermal decomposition TG DTG
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Non-isothermal decomposition kinetics and lifetime of Tb2(0-MBA)6(PHEN)2 被引量:3
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作者 ZHANGJianjun BAIJihai +2 位作者 WANGRuifen WANGShuping LIJibiao 《Rare Metals》 SCIE EI CAS CSCD 2003年第3期155-159,共5页
The thermal decomposition of Tb_2(O-MBA)_6(PHEN)_2 (O-MBA: o-methylbenzoate;PHEN: 1,10-phenanthroline) and its kinetics were studied under the non-isothermal condition bythermogravimetry-derivative thermogravimetry (T... The thermal decomposition of Tb_2(O-MBA)_6(PHEN)_2 (O-MBA: o-methylbenzoate;PHEN: 1,10-phenanthroline) and its kinetics were studied under the non-isothermal condition bythermogravimetry-derivative thermogravimetry (TG-DTG) techniques. Kinetic parameters were obtainedfrom analysis of TG-DTG curves by the Achar method and the Madhusudanan-Krishnan-Ninan (MKN) method.The most probable mechanism function was suggested by comparing the kinetic parameters. The kineticequation for the first stage can be expressed as dα/dt = Aexp(-E/RT)·3(1 - α)^(2/3). Thelifetime equation at mass loss of 10% was deduced as lnτ= -28.7429 + 19797.795/T by isothermalthermogravimetric analysis. 展开更多
关键词 thermochimica non-isothermal kinetics TG-DTG terbium complex O-methylbenzoate 1 10-PHENANTHROLINE
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Building GIS Web Services on JXTA Network 被引量:3
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作者 WANGLeichun GUANJihong ZHOUShuigeng 《Geo-Spatial Information Science》 2004年第4期268-273,共6页
In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can... In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can make P2P systems enhance overall reliability and fault-tolerance, increase autonomy, and enable ad-hoc communication and collaboration. On the other hand, Web services provides a good approach to integrate various heterogeneous systems and applications into a cooperative environment. This paper presents the techniques of combining Web services and P2P technologies into GIS to construct a new generation of GIS, which is more flexible and cooperative. As a case study, an ongoing project JGWS is introduced, which is an experimental GIS Web services platform built on JXTA. This paper also explores the schemes of building GIS Web services in a P2P environment. 展开更多
关键词 GIS (geographic information system) web services JXTA
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Fuzzy inference systems with no any rule base and linearly parameter growth 被引量:2
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作者 ShitongWANC KorrisF.L.CHUNG +2 位作者 JiepingLU BinHAN DewenHU 《控制理论与应用(英文版)》 EI 2004年第2期185-192,共8页
A class of new fuzzy inference systems New-FISs is presented.Compared with the standard fuzzy system, New-FIS is still a universal approximator and has no fuzzy rule base and linearly parameter growth. Thus, it effect... A class of new fuzzy inference systems New-FISs is presented.Compared with the standard fuzzy system, New-FIS is still a universal approximator and has no fuzzy rule base and linearly parameter growth. Thus, it effectively overcomes the second "curse of dimensionality":there is an exponential growth in the number of parameters of a fuzzy system as the number of input variables,resulting in surprisingly reduced computational complexity and being especially suitable for applications,where the complexity is of the first importance with respect to the approximation accuracy. 展开更多
关键词 Fuzzy inference Fuzzy systems Universal approximation Computational complexity Linearly parameter growth
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Thermal decomposition kinetics and lifetime of the complex of Tb_2(BA)_6(PHEN)_2 被引量:2
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作者 ZHANGJianjun WANGRuifen +3 位作者 WANGShuping LIUHongmei LIJibiao BAIJihai 《Rare Metals》 SCIE EI CAS CSCD 2004年第2期126-130,共5页
The thermal behavior of Tb_2(BA)_6(PHEN)_2 (BA: benzoate, and PHEN:1,10-phenanthroline) in a static air atmosphere was investigated by TG-DTG, SEM and IR techniques.By the kinetic method of processing thermal analysis... The thermal behavior of Tb_2(BA)_6(PHEN)_2 (BA: benzoate, and PHEN:1,10-phenanthroline) in a static air atmosphere was investigated by TG-DTG, SEM and IR techniques.By the kinetic method of processing thermal analysis data put forward by Malek et al., it is definedthat the kinetic model for the first-step thermal decomposition is SB(m, n). The activation energyE for this step reaction is 99.07 kJ/mol, the entropy of activation ΔS~≠ is -84.72 J/mol, theenthalpy of activation ΔH~≠ is 94.26 kJ/mol, the free energy of activation ΔG~≠ is 144.77 kJ/moland the pre-exponential factor lnA is 20.93. The lifetime equation at mass-loss of 10% was deducedas lnτ = -29.0312 + 19760.83/T by isothermal thermogravimetric analysis. 展开更多
关键词 LIFETIME KINETICS benzoic acid terbium complex thermal decomposition
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Distributed certification application via a trusted dealer 被引量:1
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作者 刘端阳 潘雪增 平玲娣 《Journal of Zhejiang University Science》 EI CSCD 2003年第5期555-559,共5页
Distributed certification via threshold cryptography is much more secu re than other ways to protect certification authority (CA) 's private key,and c an tolerate some intrusions. As the original system such as IT... Distributed certification via threshold cryptography is much more secu re than other ways to protect certification authority (CA) 's private key,and c an tolerate some intrusions. As the original system such as ITTC,etc.,is unsaf e ,inefficient and impracitcal in actual network environment,this paper brings u p a new distributed certification scheme,which although it generates key shares concentratively,it updates key shares distributedly,and so,avoids single-po in t failure like ITTC. It not only enhances robustness with Feldman verification and SSL protocol,but can also change the threshold (t,k) flexibly and robu stly,and so,is much more practical. In this work,the authors implement the prototype sy stem of the new scheme and test and analyze its performance. 展开更多
关键词 Distributed certification Trusted dealer ROBUST Flex ible
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MINING CYCLIC GENERALIZED ASSOCIATION RULES 被引量:1
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作者 XuMin JinYuanping +1 位作者 ZhuWujia LiWenwu 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第1期98-102,共5页
Discovering cyclic generalized association rules from transaction datbases can reveal the relationship of differ-ent levels of the taxonomies and display cyclic variations over time.Information about such variations i... Discovering cyclic generalized association rules from transaction datbases can reveal the relationship of differ-ent levels of the taxonomies and display cyclic variations over time.Information about such variations is great use of better identifying trends in associations and forecast-ing.Because cyclic rules are quite sensitive to a littlenoise,this paper uses the noise-ratio as the criterion of i-dentifing cydclic itemsets for dealing with the problem and utilizes the cycle-pruning technique to reduce the comput-ing time of the data mining process by exploiting the real-tionship between the cycle and generalized frequent item-sets.The paper gives the algorithm of mining cyclic gen-eralized itemsets(CGI).Experiment shows that the CGI algorithm can efficiently yield results. 展开更多
关键词 generalized ASSOCIATION RULES CYCLIC genera-lized ASSOCIATION RULES noise-ratio cycle-pruning CGI algorithm CGI算法 周期性一般关联规则 噪声比 事务数据库
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Non-isothermal Kinetics of the First-stage Decomposition Reaction of Cobalt Oxalate Dihydrate 被引量:1
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作者 ZHANGJian-jun RENNing BAIJi-hai 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第4期501-504,共4页
关键词 Cobalt oxalate dihydrate Non-isothermal kinetics Thermal decomposition TG-DTG
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Positive Solutions of a Second-Order Three-point Boundary Value Problem 被引量:1
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作者 李兆兴 张中新 《Northeastern Mathematical Journal》 CSCD 2002年第2期130-136,共7页
The existence of positive solutions is established for a nonlinear second-order three-point boundary value problem. The result improves and extends the main result in Electron J. Differential Equations, 34(1999), 1-8.
关键词 three-point boundary value problem positive solution EXISTENCE fixed point
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Design and Evaluation of Dynamic Replication Strategies for a High—Performance Data Grid 被引量:1
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作者 KavithaRanganathan IanFoster 《International Conference on Computing in High Energy and Nuclear Physics》 2001年第1期712-715,共4页
Physics experiments that generate large amounts of data need to be able to share it with researchers around the world .High performance grids facilitate the distribution of such data to geographically remote places.Dy... Physics experiments that generate large amounts of data need to be able to share it with researchers around the world .High performance grids facilitate the distribution of such data to geographically remote places.Dynamic replication can be used as a technique to reduce bandwidth consumption and access latency in accessuing these huge amounts of data.We describe a simulation framework that we have developed to model a grid scenario,which enables comparative studies of alternative dynamic replication strategies.We present preliminary results obtained with this simulator,in which we evaluate the performance of six different replication strategies for three different kinds of access patterns.The simulation results show that the best strategy has significant savings in latency and bandwidth consumption if the access patterns contain a moderate amount of gerographical locality. 展开更多
关键词 物理实验 数据处理 高性能数据网络 动力反响对策
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Cardiac MR image segmentation using CHNN and level set method 被引量:1
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作者 WangHongyuan ZhouZeming +1 位作者 HengPhengann XiaDeshen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第4期690-695,共6页
Although cardiac magnetic resonance imaging (MRI) can provide high spatial resolution image, the area gray level inhomogenization, weak boundary and artifact often can be found in MR images. So, the MR images segmenta... Although cardiac magnetic resonance imaging (MRI) can provide high spatial resolution image, the area gray level inhomogenization, weak boundary and artifact often can be found in MR images. So, the MR images segmentation using the gradient-based methods is poor in quality and efficiency. An algorithm, based on the competitive hopfield neural network (CHNN) and the curve propagation, is proposed for cardiac MR images segmentation in this paper. The algorithm is composed of two phases. In first phase, a CHNN is used to classify the image objects, and to make gray leve lbomogenization and to recognize weak boundaries in objects. In second phase, based on the classified results, the level set velocity function is created and the object boundaries are extracted with the curve propagation algorithm of the narrow band-based level set. The test results are promising and encouraging. 展开更多
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Robust adaptive neural network control with supervisory controller 被引量:1
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作者 ZhangTianping MeiJiandong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第4期628-631,共4页
The problem of direct adaptive neural network control for a class of uncertain nonlinear systems with unknown constant control gain is studied in this paper. Based on the supervisory control strategy and the approxima... The problem of direct adaptive neural network control for a class of uncertain nonlinear systems with unknown constant control gain is studied in this paper. Based on the supervisory control strategy and the approximation capability of multilayer neural networks (MNNs), a novel design scheme of direct adaptive neural network controller is proposed. The adaptive law of the adjustable parameter vector and the matrix of weights in the neural networks and the gain of sliding mode control term to adaptively compensate for the residual and the approximation error of MNNs is determined by using a Lyapunov method. The approach does not require the optimal approximation error to be square-integrable or the supremum of the optimal approximation error to be known. By theoretical analysis, the closed-loop control system is proven to be globally stable in the sense that all signals involved are bounded, with tracking error converging to zero. Simulation results demonstrate the effectiveness of the approach. 展开更多
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Research on Optimize Prediction Model and Algorithm about Chaotic Time Series
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作者 JIANGWei-jin XUYu-sheng 《Wuhan University Journal of Natural Sciences》 CAS 2004年第5期735-739,共5页
We put forward a chaotic estimating model, by using the parameter of the chaotic system, sensitivity of the parameter to inching and control the disturbance of the system, and estimated the parameter of the model by u... We put forward a chaotic estimating model, by using the parameter of the chaotic system, sensitivity of the parameter to inching and control the disturbance of the system, and estimated the parameter of the model by using the best update option. In the end, we forecast the intending series value in its mutually space. The example shows that it can increase the precision in the estimated process by selecting the best model steps. It not only conquer the abuse of using detention inlay technology alone, but also decrease blindness of using forecast error to decide the input model directly, and the result of it is better than the method of statistics and other series means. Key words chaotic time series - parameter identification - optimal prediction model - improved change ruler method CLC number TP 273 Foundation item: Supported by the National Natural Science Foundation of China (60373062)Biography: JIANG Wei-jin (1964-), male, Professor, research direction: intelligent compute and the theory methods of distributed data processing in complex system, and the theory of software. 展开更多
关键词 chaotic time series parameter identification optimal prediction model improved change ruler method
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Grid Technologies & Applications:Architecture & Achievements
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作者 IanFoster 《International Conference on Computing in High Energy and Nuclear Physics》 2001年第1期29-34,共6页
The 18 months since CHEP'2000 have seen significant advances in Grid computing,both within and outside high energy physics,While in early 2000,Grid Computing was a novel concept that most CHEP attendees were being... The 18 months since CHEP'2000 have seen significant advances in Grid computing,both within and outside high energy physics,While in early 2000,Grid Computing was a novel concept that most CHEP attendees were being exposed to for the first time,we now see considerable consensus on Grid architecture,a solid and widely adopeted technology base,major funding initiatives,a wide variety of projects developing applications and technologies,and major deployment projects aimed at creating robust Grid infrastructures,I provide a summary of major developments and trends,focusing on the Globus open source Grid software project and the GriPhyN data grid project. 展开更多
关键词 高能物理学 GRID技术 结构
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Influence of external field and particle size upon theoretical photoelectron emission spectral response of silver nano-particles embedded in BaO thin film
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作者 杨海 杨黎东 +1 位作者 马勇 杨智 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第8期1665-1670,共6页
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Wavelet Energy Feature Extraction and Matching for Palmprint Recognition 被引量:19
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作者 Xiang-QianWu Kuan-QuanWang DavidZhang 《Journal of Computer Science & Technology》 SCIE EI CSCD 2005年第3期411-418,共8页
According to the fact that the basic features of a palmprint, includingprincipal lines, wrinkles and ridges, have different resolutions, in this paper we analyzepalmprints using a multi-resolution method and define a ... According to the fact that the basic features of a palmprint, includingprincipal lines, wrinkles and ridges, have different resolutions, in this paper we analyzepalmprints using a multi-resolution method and define a novel palmprint feature, which calledwavelet energy feature (WEF), based on the wavelet transform. WEF can reflect the wavelet energydistribution of the principal lines, wrinkles and ridges in different directions at differentresolutions (scales), thus it can efficiently characterize palmprints. This paper also analyses thediscriminabilities of each level WEF and, according to these discriminabilities, chooses a suitableweight for each level to compute the weighted city block distance for recognition. The experimentalresults show that the order of the discriminabilities of each level WEF, from strong to weak, is the4th, 3rd, 5th, 2nd and 1st level. It also shows that WEF is robust to some extent in rotation andtranslation of the images. Accuracies of 99.24% and 99.45% have been obtained in palmprintverification and palmprint identification, respectively. These results demonstrate the power of theproposed approach. 展开更多
关键词 BIOMETRICS palmprint recognition wavelet energy feature weighted cityblock distance
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Online Palmprint Identification System for Civil Applications 被引量:4
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作者 DavidZhang Guang-MingLu +1 位作者 AdamsWai-KinKong MichaelWong 《Journal of Computer Science & Technology》 SCIE EI CSCD 2005年第1期70-76,共7页
In this paper, a novel biometric identification system is presented toidentify a person''s identity by his/her palmprint. In contrast to existing palmprint systems forcriminal applications, the proposed system... In this paper, a novel biometric identification system is presented toidentify a person''s identity by his/her palmprint. In contrast to existing palmprint systems forcriminal applications, the proposed system targets at the civil applications, which requireidentifying a person in a large database with high accuracy in real-time. The system is constitutedby four major components: User Interface Module, Acquisition Module, Recognition Module and ExternalModule. More than 7,000 palmprint images have been collected to test the performance of the system.The system can identify 400 palms with a low false acceptance rate, 0.02%, and a high genuineacceptance rate, 98.83%. For verification, the system can operate at a false acceptance rate, 0.017%and a false rejection rate, 0.86%. The execution time for the whole process including imagecollection, preprocessing, feature extraction and matching is less than 1 second. 展开更多
关键词 palmprint identification BIOMETRICS personal authentication
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