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.

In this thesis, we proposed an innovation ideal that is employment of laser to extract finger feature, and constructed laser speckle recognition systems for this kind of feature. When projecting laser on the object surface, the speckle could be obtained to represent the characteristic of object surface by collecting scattered light. Two measurement of scattered light was adopted. First is laser signal recording the strength of scattered light when laser scan across the finger. The second is laser speckle image which is demonstrated when projecting the laser on the fingerprint and simultaneously collecting the scatter light by CCD. We proposed two recognition systems for laser signal and laser speckle. Besides, the proposed laser speckle fingerprint recognition system combines biometric detection, it can accurately distinguish biometric and non-biometric speckle. Experimental results demonstrate that proposed laser speckle recognition systems are feasible and with excellent ability of identity verification.

The high-volume air sampling (PS-1) and micro-orifice uniform deposit impactor (MOUDI) were used to measure the concentrations of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere for four seasons at Zuoying and Siaogang in Kaohsiung city, together with the size distributions. Also, the CMB (Chemical Mass Balance) receptor model was employed to determine the potential sources of PAHs. The results show that the highest concentrations of PAHs occurred in winter, being 143.9 ng/m3 and 182.9 ng/m3 at Zuoying and Siaogang, respectively; while the lowest concentrations of PAHs occurred in summer, being 81.4 ng/m3 and 95.2 ng/m3. The low-weight PAHs in the two sites were abundant in gaseous phase, being 55.89 - 95.89 % and 67.07 - 96.61 % at Zuoying and Siaogang, respectively. Meanwhile, the high-weight PAHs were almost present in particulate phase, being 55.24 - 83.50 % and 46.87 - 77.26 % at Zuoying and Siaogang, respectively. The sizes of 50th percentile of cumulative size distribution, d50 of Zuoying and Siaogang were 0.89 £gm and 0.35 £gm, respectively. Hence, most atmospheric PAHs existed in fine-particle ranges (¡Õ1.0£gm). The results of by CMB receptor modeling indicated that the major sources of pollution was exhaust emission (49 - 62 %) in Zuoying, and was burning source (49 - 64 %) in Siaogang.

Piero Manzoni (1933-1963) is one of the best-known and under-theorized artists in all of postwar Europe. His body of work includes a range of practices from monochrome painting to readymade objects, from participatory sculpture to designs for architecture. More than simply innovative in its form and media, however, Manzoni's practice articulates a politics of the body and of the self that departs radically from the belief systems at stake in the work of his contemporaries in both Europe and America. If other postwar artists still claimed access to transcendence, to nature, or to autonomous subjectivity, Manzoni responds with works that reveal the body and the self as material and discursive effects of power relations. / History of Art and Architecture

Techn. Universiẗat, Diss., 1999--Berlin.

Universiẗat, Diss., 2004--Jena.

Techn. Universiẗat, Diss., 2004--Dresden.

There are numerous pre-existing fingerprint development techniques, however, often prints are difficult to develop, depending on their age or the surface upon which they have been deposited. Forensic scientists are relentlessly looking for new and better methods to enhance fingerprints. More recent technologies have higher sensitivity to very low levels of constituents present in residues and so are able to unearth significant details from a person's fingerprints at molecular level e.g. DNA, drug metabolites. Therefore, research continues in an attempt to generate novel, nondestructive processes that can enhance latent fingerprints. Exposing fingerprints to the p-block compounds selenium dioxide (SeO2), phosphorus sulfides (P4Sx) and phosphonitrilic chloride trimer (NPCl2)3, in the vapour phase resulted in latent prints being visualized on a range of media. Selenium dioxide revealed prints on metal surfaces (e.g. brass) which were enhanced further upon formation of a dark brown coating of copper-selenide formed on the surface when exposed to moisture, giving a better contrast. P4S3 vapour revealed a higher percentage of prints and samples had greater stability in air while although (NPCl2)3 was able to develop fingerprints, the low quality was undesirable. Initially it was thought that (NPCl2)3 has the potential for further derivatisation but was proven very difficult to interact with compounds especially those with the potential to induce fluorescence. However, all three compounds are commercially available and sublimation techniques are straightforward.

Submitted by Hora Fontes Nadja Maria (pospetro@ufba.br) on 2012-11-13T17:46:25Z No. of bitstreams: 1 DissertacaoCYR.pdf: 3281722 bytes, checksum: 64f10f3087a32e1fa0cf089355c9c7aa (MD5) / Made available in DSpace on 2012-11-13T17:46:25Z (GMT). No. of bitstreams: 1 DissertacaoCYR.pdf: 3281722 bytes, checksum: 64f10f3087a32e1fa0cf089355c9c7aa (MD5) Previous issue date: 2012 / FAPESB / O desenvolvimento desta pesquisa faz parte dos projetos da Pós-Graduação em Geoquímica: Petróleo e Meio Ambiente – POSPETRO e está contemplada no âmbito da Rede Cooperativa em Recuperação de Áreas Contaminadas por Atividades Petrolíferas - RECUPETRO, estabelecida pelo Núcleo de Estudos Ambientais do Instituto de Geociênicas da Universidade Federal da Bahia - NEA/IGEO/UFBA. Nesta pesquisa, se fez um estudo teórico dos aspectos físico-geoquímicos dos asfaltenos e, do processo e informações geradas a partir da hidropirólise de asfaltenos. Além disso, este estudo avaliou o processo de separação e de limpeza dos asfaltenos obtidos a partir de duas amostras de arenitos impregnados de óleos (um arenito betuminoso da Fm. Parambóia da Bacia do Paraná e um arenito impregnado de óleo degradado da Fm. Ilhas ou Candeias da Bacia do Recôncavo). A geoquímica de asfaltenos permite obter informações correlacionáveis com as geradas em condições naturais, por uma rocha geradora, devido à semelhança geoquímica dos asfaltenos com o querogênio. A hidropirólise de asfaltenos é uma técnica de oxidação térmica usada amplamente em estudos geoquímicos para procurar entender os processos, reações e composições das estruturas complexas, como são os asfaltenos. As substâncias geradas durante o processo hidropirolítico servem para avaliar os parâmetros geoquímicos do óleo original e para definir estretégias tecnológicas e ambientais que melhorem a industrialização e manuseio de óleos com elevado conteúdo de asfalteno. / Salvador

Context. For a user to gain access to a protected resource on the web,the user needs to get authenticated. There are different forms of authenti-cation, among the most common is the ordinary user name and passwordscheme. This scheme is very simple to implement, but it suffers from se-curity vulnerabilities and requires the user to remember passwords to allaccounts. Two-factor authentication could be one answer to increase thesecurity where one-factor authentication is lacking. However, depending onthe implementation, two-factor authentication could still be insecure andeven more user-unfriendly. Objectives.  In this study, we investigate if our implementation of two-factor authentication has any advantages to existing ones. Our goal is topresent a secure and user-friendly authentication scheme that uses bothpassword and fingerprint. Methods. A literary study was performed in order to collect informationon similar systems and subjects in order to build a comparable authentica-tion model. The collected information and proposed model was then usedto analyze possible drawbacks and to answer research questions. Results. Results derive from the comparison between our proposed modeland two Google two-factor authentication solutions. Conclusions. The results yielded from the literary study and analysisshows that our proposed model does not add any advantages concerningsecurity. Our model does however provide better ease of use in comparisonwith similar two-factor authentication solutions from Google.