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1.
A summarization of one of the most successful behavioral biometric recognition methods: signature recognition. Probably this is one of the oldest biometric recognition methods, with high legal acceptance. Technological advances have made possible new perspectives for signature recognition, by means of capturing devices which provide more than the simple signature image: pressure, acceleration, etc., making it even more difficult to forge a signature.  相似文献   

2.
Data fusion in biometrics   总被引:4,自引:0,他引:4  
Any biometric system has drawbacks and cannot warranty 100% identification rates, nor 0% false acceptance and rejection ratios. One way to overcome the limitations is through a combination of different biometric systems. In addition, a multimodal biometric recognition is more difficult to fool than a single, biometric system, because it is more unlikely to defeat two or three biometric systems than one. This paper summarizes the different data fusion levels, and how it must be performed in order to improve the results of each combined system on its own  相似文献   

3.
Nowadays many systems need a portable media to store some sensible data, such as smart cards. The information can be protected by the user with his Personal Identification Number (PIN), or through biometrics. Unfortunately, there is not a smart card today that can verify the biometric template inside it, performing this task in the terminal. The author has developed the algorithms and data structures needed to solve this problem. Therefore, he has created a smart card with user biometric authentication, based on an Open Platform smart card (in this case, a JavaCard). To achieve these results, different biometric techniques have been studied: speaker verification, hand geometry and iris recognition. Experimental results are given to show the viability of the prototype developed  相似文献   

4.
When considering biometrics for a Personal Identification System, different modalities can be considered. The final selection will depend on specific application requirements. From the several modalities existing nowadays, vascular systems have appeared on the scene lately. Vein-based identification is claimed to be as reliable as fingerprint or iris identification, but with the usability of hand geometry or even the face. As with any other biometric modalities, vascular solutions have to be deeply analyzed for all relevant factors that could affect their performance or the security level achieved. This will show the analysis of the performance and security achieved by a commercial vascular biometric system, when being applied in several real-world scenarios. These scenarios will cover typical office environments to the more extreme environments, such as extreme light and temperatures, as those suffered in a banking ATM, or with high humidity such as in a gym. The results will show the strengths of this modality, as well as those points where further improvements are needed.  相似文献   

5.
Access control system with hand geometry verification and smartcards   总被引:1,自引:0,他引:1  
An access control system that joins the uniqueness of biometric verification, as well as the storage security and processing capabilities of smart cards, is defined here. The biometric technique chosen has been hand geometry, which is considered to provide low/medium security (there are other much more secure, as fingerprint, iris or retina), to be easy to use, to achieve high acceptance by users, and which performance is given throughout fast processing and medium cost. Also, the small template size needed for each user is positive for storage and processing capabilities required in the system. But the innovation in the system proposed is that the smart card not only stores the user's template, but also performs the verification process with the features set by the terminal to the card. With this improvement, the security of the system has risen because the template is never extracted from the card, avoiding duplication of such sensible data. The specifications for the enrolment process will be presented as well as the applications where this new system is recommended  相似文献   

6.
Over the past few years, the authors have tried to integrate biometrics into a smart card. In this paper, to improve error rates obtained with hand geometry biometrics and the costs with the iris recognition system, fingerprints are used. This technique, quite well known in the industry and deeply studied for the last century, has improved its electronic sensors, pulling down prices and, therefore, enabling its use in many more applications. The first step, as in every biometric system, is to obtain an image of the user's fingerprint. After this, a pre-processing algorithm is applied, which enables feature extraction to obtain the location and type of all minutiae, i.e., the discontinuities in the ridges and valleys of the fingerprint. Due to the fact that it is not possible to always catch the same number of minutiae, a special matching algorithm should be applied to compare the feature vector with the corresponding user's template. Efforts to integrate this matching algorithm in a low computer power device, such as a smart card, are given, showing the paths that should be followed in order to improve the security of access control and payment systems available today.  相似文献   

7.
Biometrics can offer improved security for access control. Several biometric devices can be adapted to our special requirements and some criterion is needed to choose the best solution for us. On the one hand, it is possible to use a standalone embedded system. On the other hand, a low-cost PC-based system can be better fitted to our special requirements, by means of special purpose software. With the actual reduction on the price of informatic components, it can be a good alternative. This describes one of these systems for door-opening with the user's fingerprint. Special emphasis is given on the design, advantages, and inconveniences with respect to embedded systems.  相似文献   

8.
On the vulnerability of biometric security systems   总被引:1,自引:0,他引:1  
This paper presents an overview of the weakness of biometric security systems and possible solutions to improve it. Different levels of attack are described, and the strengths and weaknesses of the main biometric system are emphasized. Solutions are provided with special emphasis on cryptography and watermarking techniques.  相似文献   

9.
Due to the great increase in Information Technology (IT) systems where user authentication is needed, security in those systems relies on using PINs or passwords. During recent years, the scientific community has been trying to improve biometric techniques to be accepted as an alternative to other user authentication schemes. One of the sectors where user identity must be verified, is the identification cards sector. In fact, if great security wants to be achieved, smart cards should be used. But cardholder verification is performed using Card Holder Verification Keys (CHV-Keys), which are PIN-based. The authors are trying to integrate fingerprint verification inside a smart card, following their works in the past. The fingerprint scheme used is shown, and the work to achieve the integration inside a commercial smart card is detailed.  相似文献   

10.
打击恐怖主义首先要预防恐怖分子,生物识别技术有助于将恐怖分子从人群中识别出来.耳朵是长期保持稳定的一个生物特征,并且耳朵的独特性十分明显.介绍了耳朵识别系统的系统功能和设计思路,采用VC 6.0和SQL SERVER 2000数据库,实现耳朵图像数据采集、图像预处理、图像存储等基本功能.  相似文献   

11.
A biometric identification system, based on the processing of the human iris by the dyadic wavelet transform, has been introduced. The procedure to obtain an iris signature of 256 bits has been described, as well as the feature extraction block and the verification system. The results have shown that the system can achieve high rates of security.  相似文献   

12.
A new class of techniques for multisensor fusion and target recognition is proposed using sequence comparison by dynamic programming and multiple model estimation. The objective is to fuse information on the kinematic state and “nonkinematic” signature of unclassified targets, assessing the joint likelihood of all observed events for recognition. Relationships are shown to previous efforts in pattern recognition and state estimation. This research applies “classical” speech processing-related and other sequence comparison methods to moving target recognition, extends the efforts of previous researchers through improved fusion with kinematic information, relates the proposed techniques to Bayesian theory, and applies parameter identification methods to target recognition for improved understanding of the subject in general. The proposed techniques are evaluated and compared with existing approaches using the method of generalized ambiguity functions, which lends to a form of Cramer-Rao lower bound for target recognition  相似文献   

13.
State-of-the-art in speaker recognition   总被引:1,自引:0,他引:1  
Recent advances in speech technologies have produced new tools that can be used to improve the performance and flexibility of speaker recognition. While there are few degrees of freedom or alternative methods when using fingerprint or iris identification techniques, speech offers much more flexibility and different levels to perform recognition: the system can force the user to speak in a particular manner, different for each attempt to enter. Also, with voice input, the system has other degrees of freedom, such as the use of knowledge/codes that only the user knows, or dialectical/semantical traits that are difficult to forge. This paper offers an overview of the state-of-the-art in speaker recognition, with special emphasis on the pros and cons, and the current research lines. The current research lines include improved classification systems, and the use of high level information by means of probabilistic grammars. In conclusion, speaker recognition is far away from being a technology where all the possibilities have already been explored.  相似文献   

14.
During the last years, the authors are designing a high resolution fingerprint identification system based on minutiae extraction. In this sense, a fingerprint thinning algorithm by means of morphological image processing operations is presented, to improve the minutiae map involved. The first step, as in every biometric system, is to obtain an image of the user's fingerprint. After this, a pre-processing algorithm is applied which enables feature extraction steps to obtain the location and type of all minutiae; i.e., the discontinuities in the ridges and valleys of the fingerprint.  相似文献   

15.
《中国航空学报》2023,36(3):316-334
The battlefield environment is changing rapidly, and fast and accurate identification of the tactical intention of enemy targets is an important condition for gaining a decision-making advantage. The current Intention Recognition (IR) method for air targets has shortcomings in temporality, interpretability and back-and-forth dependency of intentions. To address these problems, this paper designs a novel air target intention recognition method named STABC-IR, which is based on Bidirectional Gated Recurrent Unit (BiGRU) and Conditional Random Field (CRF) with Space-Time Attention mechanism (STA). First, the problem of intention recognition of air targets is described and analyzed in detail. Then, a temporal network based on BiGRU is constructed to achieve the temporal requirement. Subsequently, STA is proposed to focus on the key parts of the features and timing information to meet certain interpretability requirements while strengthening the timing requirements. Finally, an intention transformation network based on CRF is proposed to solve the back-and-forth dependency and transformation problem by jointly modeling the tactical intention of the target at each moment. The experimental results show that the recognition accuracy of the jointly trained STABC-IR model can reach 95.7%, which is higher than other latest intention recognition methods. STABC-IR solves the problem of intention transformation for the first time and considers both temporality and interpretability, which is important for improving the tactical intention recognition capability and has reference value for the construction of command and control auxiliary decision-making system.  相似文献   

16.
雷达距离高分辨特性,即目标的一维高分辨距离像特性,能够体现目标的形状及结构信息,且易获取,有利于对目标进行准确识别,这已成为目前雷达目标识别领域的一个重要研究方向。开展目标一维高分辨特性研究的一个重要基础是测量,因而通过测量目标的一维高分辨距离像并分析目标特性,对目标识别具有重大理论意义与实际应用价值。基于此,文章利用实验室现有全相参新体制雷达导引头目标测量平台,对海面舰船目标的距离高分辨特性进行了初步实测,获取了海面舰船的米级高分辨距离像,为今后深入开展海面舰船目标识别研究奠定了坚实基础。  相似文献   

17.
Automatic recognition of ISAR ship images   总被引:6,自引:0,他引:6  
Inverse synthetic aperture radar (ISAR) produces images of ships at sea which human operators can be trained to recognize. Because ISAR uses the ship's own varying angular motions (roll, pitch, and yaw) for cross-range resolution, the viewing aspect and cross-range scale factor are continually changing on time scales of a few seconds. This and other characteristics of ISAR imaging make the problem of automatic recognition of ISAR images quite distinct from the recognition of optical images. The nature of ISAR imaging of ships, and single-frame and multiple-frame techniques for segmentation, feature extraction, and classification are described. Results are shown which illustrate a capability for automatic recognition of ISAR ship imagery  相似文献   

18.
严玉龙  王厚枢 《航空学报》1991,12(11):621-628
 研究数字条纹图象的自动检测与判读处理的理论与技术,在微型通用数字图象处理系统上建立了一套条纹自动检测与判读处理的软系统,实现了条纹图象的输入、定位、预处理、骨架化、细化、修补与光滑、计数、插值及三维振幅场输出等功能,对类似的散斑干涉条纹和莫尔条纹的判读处理有理论参考价值。  相似文献   

19.
传统的合成孔径雷达舰船检测识别需要分两步实现,检测识别精度和效率难以满足实际应用需求。本文结合注意力机制和YOLO-V3网络提出了注意力YOLO-V3网络实现合成孔径雷达舰船检测识别一体化。同时,利用公开的AIR-SARShip-1.0数据集和OpenSARShip数据集构建了大场景舰船检测识别数据集,用于验证目标检测识别性能。实验结果表明,本文提出的注意力YOLO-V3网络可以获得较高的检测识别精度,证明了本文方法的有效性。  相似文献   

20.
在室内无线通信模型的优化中,需要区分不同的墙壁对象.而对于室内墙壁的图像可以看作是纹理图像.尝试利用数据融合的方法对这些纹理图像进行识别.实验结果表明,数据融合的方法对相似的纹理图像具有较好的识别效果.  相似文献   

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