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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Investigating sex differences in fingerprint minutiae density of the core region utilizing the minutiae: ridge-length ratio

Reinart, Leonard Francis 12 March 2016 (has links)
In an attempt to develop a statistical model for fingerprint analysis, the Minutiae:Ridge-Length Ratio (MRLR) was used to examine differences between the different sexes, hands, fingers, ridge patterns, and racial groups. In regards to sex, statistically significant MRLR differences (α=0.05) were found between males and females when analyzing both individual prints (p<0.001) and entire ten-print cards (p=0.025). Further examination of the data revealed more specific differences within separate subcategories. The MRLR was significantly different (p<0.001) between males and females with both right and left hands. With respect to sex and individual finger differences, the thumb (p<0.001), index finger (p<0.001), and middle finger (p=0.015) were statistically significant. For ridge pattern, whorls (p<0.001) and ulnar loops (p<0.001) had significant differences between the sexes. Racially, males and females had statistically significant differences from one another within the Caucasian (p<0.001) and African American (p<0.001) racial groups. Further investigation of variables independent of sex highlighted other statistically significant MRLR relationships. Within the fingers, the thumb was found to be significantly different than the middle (p<0.001), ring (p<0.001), and little fingers (p<0.001); the index finger also differed from the little finger significantly (p=0.001). Comparison of level one detail demonstrated the whorl pattern was statistically different than the arch (p<0.001), radial loop (p=0.002), and ulnar loop patterns (p<0.001). No statistically significant difference was found between the right and left hands of the sample population (p=0.160). The racial subdivisions produced more complex relationships. Caucasians had statistically significant MRLR differences to African Americans (p=0.036), Hispanics (p=0.003), and Asians (p=0.046). African Americans had additional significant differences from Hispanics (p<0.001), Asians (p<0.001), and Native Americans (p=0.036). Finally, Native Americans and Hispanics shared a significant difference as well (p<0.036). However, due to the uncertainty of racial demographic data, the extrapolation of these findings to the general population may not be appropriate for forensic investigation purposes.
2

Extração de minúcias em imagens de impressões digitais / Extraction minutiae in fingerprints

Casado, Ricardo Salvino 17 June 2008 (has links)
Este trabalho descreve um método desenvolvido para a extração de minúcias em imagens de impressões digitais, baseado na abordagem clássica de binarização da imagem. O método é composto por três módulos: módulo de pré-processamento, para o aumento da discriminação visual, módulo de extração de minúcias, e módulo de pós-processamento para a remoção de falsas minúcias. As imagens de impressões digitais foram obtidas da base de dados FVC2004 (Fingerprint Verification Competition), e incluem imagens sintéticas e reais. A validação dos testes foi feita através de métodos quantitativos de medida chamados sensibilidade e especificidade. Os melhores resultados do software implementado foram obtidos com as imagens sintéticas seguido das imagens adquiridas com sensor óptico. As imagens obtidas através de sensor térmico apresentaram diferença de resultado considerável em relação às imagens dos demais bancos, pelo fato de conterem maior quantidade de ruído. / In this research a method for minutiae extraction in fingerprints images, based on classical approach of image binarization, is presented. The method is composed by three main modules: preprocessing, minutiae detection and post-processing. It was used fingerprint images from FVC2004 database (Fingerprint Verification Competition) that includes synthetic and real images. The tests validation was made through quantitative methods of measurement called sensitivity and specificity. The best results obtained with the developed software were with synthetic images followed by the images acquired with optical sensor. The results obtained with the thermal sensor images were worse than the ones obtained with synthetic and real images, showing a considerable difference, because they contain more noise.
3

Extração de minúcias em imagens de impressões digitais / Extraction minutiae in fingerprints

Ricardo Salvino Casado 17 June 2008 (has links)
Este trabalho descreve um método desenvolvido para a extração de minúcias em imagens de impressões digitais, baseado na abordagem clássica de binarização da imagem. O método é composto por três módulos: módulo de pré-processamento, para o aumento da discriminação visual, módulo de extração de minúcias, e módulo de pós-processamento para a remoção de falsas minúcias. As imagens de impressões digitais foram obtidas da base de dados FVC2004 (Fingerprint Verification Competition), e incluem imagens sintéticas e reais. A validação dos testes foi feita através de métodos quantitativos de medida chamados sensibilidade e especificidade. Os melhores resultados do software implementado foram obtidos com as imagens sintéticas seguido das imagens adquiridas com sensor óptico. As imagens obtidas através de sensor térmico apresentaram diferença de resultado considerável em relação às imagens dos demais bancos, pelo fato de conterem maior quantidade de ruído. / In this research a method for minutiae extraction in fingerprints images, based on classical approach of image binarization, is presented. The method is composed by three main modules: preprocessing, minutiae detection and post-processing. It was used fingerprint images from FVC2004 database (Fingerprint Verification Competition) that includes synthetic and real images. The tests validation was made through quantitative methods of measurement called sensitivity and specificity. The best results obtained with the developed software were with synthetic images followed by the images acquired with optical sensor. The results obtained with the thermal sensor images were worse than the ones obtained with synthetic and real images, showing a considerable difference, because they contain more noise.
4

Secure and Private Fingerprint-based Authentication

Arakala, Arathi, arathi.arakala@ems.rmit.edu.au January 2008 (has links)
This thesis studies the requirements and processes involved in building an authentication system using the fingerprint biometric, where the fingerprint template is protected during storage and during comparison. The principles developed in this thesis can be easily extended to authentication systems using other biometric modalities. Most existing biometric authentication systems store their template securely using an encryption function. However, in order to perform matching, the enrolled template must be decrypted. It is at this point that the authentication system is most vulnerable as the entire enrolled template is exposed. A biometric is irreplaceable if compromised and can also reveal sensitive information about an individual. If biometric systems are taken up widely, the template could also be used as an individual's digital identifier. Compromise in that case, violates an individual's right to privacy as their transactions in all systems where they used that compromised biometric can be tracked. Therefore securing a biometric template during comparison as well as storage in an authentication system is imperative. Eight different fingerprint template representation techniques, where templates were treated as a set of elements derived from the locations and orientations of fingerprint minutiae, were studied. Four main steps to build any biometric based authentication system were identified and each of the eight fingerprint template representations was inducted through the four steps. Two distinct Error Tolerant Cryptographic Constructs based on the set difference metric, were studied for their ability to securely store and compare each of the template types in an authentication system. The first construct was found to be unsuitable for a fundamental reason that would apply to all the template types considered in the research. The second construct did not have the limitation of the first and three algorithms to build authentication systems using the second construct were proposed. It was determined that minutiae-based templates had significant intra sample variation as a result of which a very relaxed matching threshold had to be set in the authentication system. The relaxed threshold caused the authentication systems built using the first two algorithms to reveal enough information about the stored templates to render them insecure. It was found that in cases of such large intra-sample variation, a commonality based match decision was more appropriate. One solution to building a secure authentication system using minutiae-based templates was demonstrated by the third algorithm which used a two stage matching process involving the second cryptographic construct and a commonality based similarity measure in the two stages respectively. This implementation was successful in securing the fingerprint template during comparison as well as storage, with minimal reduction in accuracy when compared to the matching performance without the cryptographic construct. Another solution is to use an efficient commonality based error tolerant cryptographic construct. This thesis lists the desirable characteristics of such a construct as existence of any is unknown to date. This thesis concludes by presenting good guidelines to evaluate the suitability of different cryptographic constructs to protect biometric templates of other modalities in an authentication system.
5

Rozpoznávání podobnosti otisků prstu / Fingerprint identification algorithm

Skoupilová, Alena January 2020 (has links)
The main goal of this thesis is to introduce the meaning of identification and specific meaning of personal identification and mainly fingerprint identification. There is introduction to the meaning of biometrics as a key field for fingerprint recognition. Thesis also introduces principals and types of automatic processing and automatic detection of fingerprints. An existing and succesful methods are being described in the thesis and an automatic fingerprint identification alghoritm is being realized and described. Reability of the alghoritm is tested within experimental database.
6

Rozpoznávání podobnosti otisků prstu / Fingerprint identification algorithm

Skoupilová, Alena January 2020 (has links)
The main goal of this thesis is to introduce the meaning of term identification and term biometrics as a key field for fingerprint recognition. Thesis also introduces principals and types of automatic processing of fingerprint images and automatic fingerprints identification algorithms. An existing and successful methods are being described in the thesis and pre-processing of fingerprint images is being realized. Automatic fingerprint identification algorithm based on distance of minutiae from the core, core type and orientation field of the fingerprint is proposed. The proposed algorithm was tested on a database of fingerprint images and was statistically analysed.
7

Biometrická identifikace otisku prstu / Biometric fingerprint identification

Hodulíková, Tereza January 2016 (has links)
This master's thesis deals with fingerprint verification. The theoretical part consist of biometry identification systems and evaluating their reliability and robustness. After that we focus on fingerprints properties needed to identification. We mention several types of fingerprint sensors, which are generaly in public use. In practical part of thesis we deal with enhancement of fingeprint image and methods of identifications. At last we created software for fingeprint identification in programming environment Matlab.
8

Piršto atspaudo naudojimas šifravimo rakto generavimui / Encryption key generation from fingerprint

Burba, Donatas 13 August 2010 (has links)
Saugiais gali būti laikomi tik užšifruoti duomenys, o šifravimas neįmanomas be šifravimo rakto. Vienas iš geriausiai žinomų ir plačiausiai naudojamų šifravimo raktų yra slaptažodis, tačiau pagrindinis jo trūkumas tas, kad jį reikia atsiminti. Šioje situacijoje gali padėti biometrija, kadangi praktiškai kiekvienas žmogus turi unikalias charakteristikas. Tačiau pagrindinė problema yra - kaip iš biometrinių charakteristikų suformuoti šifravimo raktą. Pirštų atspaudai yra gerai žinoma biometrinė charakteristika, naudojama žmonių identifikavimui ir tapatybės patvirtinimui, o USB atmintinėse ar nešiojamuosiuose kompiuteriuose integruoti pirštų atspaudų skaitytuvai jau nieko nebestebina. Kiekvienas piršto atspaudas gali būti aprašytas minutiae taškų matrica iš kurios būtų galima generuoti šifravimo raktą. Tačiau netgi to paties piršto atspaudai nėra identiški ir į tai reikia atsižvelgti. Šiame darbe pateikiamas vienas tiesioginių šifravimo raktų generavimo iš pirštų atspaudų metodas. Iš atspaudo suformuojama minutiae taškų matrica, iš jos suformuojami parametrai ir perduodami raktų generatoriams. Matricų formavimui panaudoti du produktai, realizuoti 8 generatoriai, formuojantys 64 ir 128 bitų ilgio šifravimo raktus. Sistema ištestuota su pasiruošta pirštų atspaudų duomenų baze, pateikti gauti rezultatai. / Only encrypted data can be treated as secure data and encryption is impossible without encryption key. One of the best known and widely used encryption keys is password, but the main its drawback is necessity to remember it. Biometrics may help to avoid this situation, because everyone has unique characteristics. But the main question is how to extract encryption key from biometric data. Fingerprints are well known biometric characteristic, used for people identification or authentication and fingerprint readers integrated into USB flash drives or laptops don’t cause surprise any more. Every fingerprint can be described using minutiae points’ matrix and from this matrix encryption key can be generated. But fingerprints of the same finger aren’t identical, so this must be kept in mind as well. In this research one method of direct encryption key generation from fingerprint is introduced. Minutiae matrix is structured from fingerprint image; parameters are formed and passed to encryption key generators. Two products were used for making matrix and eight generators were produced, generating encryption keys length of 64 and 128 bits. This system was tested with prepared fingerprint set and all the results are given.
9

Art, landscape and material : subject into media

Greening, Daniel John January 2010 (has links)
A research investigation that illustrates the development of the European landscape tradition as an unbroken interactive and material movement, through discussion of artists from Annibale Carracci (1560-1609) to Richard Long (1945 –). The contribution of each artist within their respective epoch will be used to propose that the subject of landscape has become an actual creative medium, integral to and consistent with the external Plein-Air technique. Thus, presenting a ‘creative narrative’ from the observed into the articulated that will demonstrate how the examination and representation of actual landscapes have become physically used within creative presentations. The study uses key artworks that have been inspired by landscape to show the shift from documentation into interaction with the reality of the natural world. This entails the chronology of the investigation and commences with the concept of Ideal Landscape, established by Carracci, within the late 16th century, through the development of the Plein-Air tradition and culminating with particular emphasis on European landscape artists’ and movements since 1945 that have interacted with actual sites and natural materials: from the ideal to the actual. Furthermore, the European transfer and diffusion of interactive and material based landscape methods, including drawing and painting outside, the collection of organic items and photography, passed and developed from one generation to the next, informs a body of personal creative work. This is a 50/50 co-dependent strand used to illustrate the practical and creative discourses between practitioner and landscape, involving the articulation of actual land materials, found objects and Plein-Air excursions to the drawing locations of previous practitioners’, sketchbooks and journals. The insights provided, by the personal practice and associated theoretical position, aid the evaluation, analysis and description of the evolution of the creative methods inherent in the development of subject into media, but not presently described in historical accounts, therefore, presenting a Material Chronology and thus the original contribution of knowledge for this investigation.
10

A New Minutiae Method Based on Partial Fingerprints

Lin, Chin-Hung 23 August 2006 (has links)
As information technologies advanced greatly in recent years, the security problem of information networks becomes all the more important. As a result, biometric identification techniques have been given considerable attention. Fingerprint-related techniques, due to these desirable properties, i.e., universality, perpetuity, collectability and particularity, are most widely applied and documented. However, in practice, collected fingerprint images are not always of good quality. They often are noisy or are even partial images. Therefore, in this research, we propose a new minutiae matching method, while using a coefficient of variation of orientation difference, a coefficient of frequency correlation, along with other image features to obtain a match based on only partial fingerprints. By the proposed method, when a score is arrived at and the test image and the database image have five minutia points matched, we have both FRR and FAR values close to 29%, and the correctness of matching reaches 70.56%.

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