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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.
171

Análise do uso da tecnologia laser aerotransportado para inventários florestais em plantios clonais de Eucalyptus sp no sul da Bahia / Analysis of the airborne laser scanning technology use for forest inventories in cloned Eucalyptus sp plantations in the southern Bahia.

Zonete, Matheus Felipe 19 June 2009 (has links)
A aplicação da tecnologia LASER aerotransportado (ALS) para realização de inventários florestais, tem se apresentado como excelente alternativa para a área de planejamento florestal, principalmente pelos ótimos resultados em termos de precisão das estimativas, pelas facilidades de uso e demais produtos e benefícios advindos do sobrevôo com o LASER. A evolução e o menor custo das tecnologias GPS e Sistemas de Medição Inercial têm sido o principal fator de sucesso para a aplicação da tecnologia ALS. Vários trabalhos de análise da tecnologia LASER aerotransportado, em inventários florestais, alguns até mesmo em escalas comerciais (NAESSET, 2007), têm sido realizados principalmente na Europa e no Canadá. Os resultados têm sido muito atraentes, dentre os quais se destacam as estimativas de volume e de área basal que têm apresentado erros de no máximo 8,4%, dependendo das configurações da área amostrada. Sendo assim, este trabalho teve por objetivo analisar o uso da tecnologia ALS para a realização de inventários florestais em níveis de parcela e talhão em plantios clonais de Eucalyptus sp, no sul do estado da Bahia. Para tanto foram realizados levantamentos de campos que permitiram a estimação de parâmetros como área basal, altura de árvores média e das dominantes e volume, em parcelas circulares de treze metros de raio, nas quais foram coletados o diâmetro de todas as árvores e a altura de uma a cada sete árvores da parcela. A área sobrevoada para coleta dos dados LASER foram duas faixas de aproximadamente 2x20km. Os dados LASER foram processados para se obter os percentís das observações ALS nos níveis 10 (f_h10), 30 (f_h30), 50 (f_h50), 70 (f_h70) e 90 (f_h90), bem como a densidade de pontos nos respectivos percentís (f_p10, f_p30, f_p50, f_p70 e f_p90), e a altura média (f_havg) e o desvio padrão (f_hstd) desses pontos. Essas estatísticas foram utilizadas em modelos de regressão para estimar diâmetro médio, altura média, altura dominante, área basal e volume das parcelas amostradas. Para o volume, uma avaliação exploratória de diferentes combinações de variáveis permitiu a definição das relações mais promissoras e a utilização dessas variáveis mais promissoras no ajuste de modelos já consagrados na área de biometria e inventário florestal. As observações ALS que melhor ajustaram diâmetro médio foram f_h30 e f_p30, com R²=0,88 e RQEM%=0,0004; para altura média, f_h10 e f_h90 geraram boas estimativas, com R²=0,94 e RQEM%=0,0003, enquanto que para altura dominante, as melhores estimativas foram obtidas com f_h90, apresentando R²=0,96 e RQEM%=0,0003; e para área basal, os melhores ajustes usaram idade, f_h10 e f_havg, sendo R²=0,92 e RQEM%=0,0016. No caso de volume, os dois melhores modelos exploratórios apontam para o uso de idade, f_h30 e f_p90, em ambos os casos, e ambos com R² entre 0,94 e 0,95 e RQEM% entre 0,002 e 0,003. Já, dentre os modelos biométricos testados, os melhores foram os de Schumacher ajustado com idade e f_h90; Clutter ajustado com idade, f_havg e f_h70; e de Buckman ajustado com idade, f_havg e f_h10. / The application of the airborne laser scanning (ALS) technology for forest inventories execution, have been presented as an excellent alternative to the forest planning area, particularly by the excellent results in terms of accuracy of the estimates, by the facilities of usage and other products and benefits derived from LASER overflight. The technology evolution and lower cost for GPS and Inertial Measurement Units have been the main factor of the success for ALS technology application. Several studies of ALS technology analysis in forest inventories, some even in commercial scales (NAESSET, 2007), have been conducted mainly in Europe and Canada. The results have been very attractive, among which there are the volume and basal area estimates which have made errors of up to 8.4% depending on the settings of the sampled area. Thus, this study aimed to examine the use of the ALS technology for forest inventories executions at plot and stands levels in clonal Eucalyptus sp plantations in the south of Bahia state. Field surveys were conducted to provide the parameters estimation such as diameter, tree heights, basal area and volume in circular plots of thirteen-meter radius, which were the diameter of all trees and height of a the seven trees of each plot. The overflown areas for LASER data collection were two bands of approximately 2x20km. LASER data were processed to obtain the percentiles of the ALS observations in the following levels 10 (f_h10), 30 (f_h30), 50 (f_h50), 70 (f_h70) e 90 (f_h90), and 90 (f_h90) and the density of points in the respective percentiles (f_p10, f_p30, f_p50, f_p70 and f_p90), the average height of the points (f_havg) and the standard deviation (f_hstd). These statistics were used in the regression models to estimate mean diameter, mean height, dominant height, basal area and volume of the sampled plots. For the volume, an exploration of different combinations of the variables supported the definition of the most promising relations and most promising use of these variables in the set of models already established in the biometrics and forest inventory area.The ALS observations that better fit to the average diameter were f_h30 and f_p30, resulting in a R²=0.88 and RQEM%=0.0004; for the average height, f_h10 and f_h90 generate good estimates, having R²=0.94 and RQEM%=0. 0003, therefore for the dominant height, the best estimates were obtained with f_h90, showing R²=0.96 and RQEM%=0.0003. For the basal area, the best fit used age, f_h10 and f_havg, presenting a R²=0.92 and RQEM%=0.0016. In the volume case, the two best exploratory models point to the use of age, f_h30 and f_p90, both with R ² between 0.94 and 0.95 and RQEM% between 000.2 and 000.3. Among the biometric tested models, the best were Schumacher fitted by age and f_h90; Clutter fitted by age, f_havg and f_h70; Buckman fitted by age, f_havg and f_h10.
172

Mobile personal authentication using fingerprint.

January 2004 (has links)
Cheng Po Sum. / Thesis submitted in: July 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 64-67). / Abstracts in English and Chinese. / List of Figures --- p.i / List of Tables --- p.iii / Acknowledgments --- p.iv / 摘要 --- p.v / Thesis Abstract --- p.vi / Chapter 1. --- Mobile Commerce --- p.1 / Chapter 1.1 --- Introduction to Mobile Commerce --- p.1 / Chapter 1.2 --- Mobile commence payment systems --- p.2 / Chapter 1.3 --- Security in mobile commerce --- p.5 / Chapter 2. --- Mobile authentication using Fingerprint --- p.10 / Chapter 2.1 --- Authentication basics --- p.10 / Chapter 2.2 --- Fingerprint basics --- p.12 / Chapter 2.3 --- Fingerprint authentication using mobile device --- p.15 / Chapter 3. --- Design of Mobile Fingerprint Authentication Device --- p.19 / Chapter 3.1 --- Objectives --- p.19 / Chapter 3.2 --- Hardware and software design --- p.21 / Chapter 3.2.1 --- Choice of hardware platform --- p.21 / Chapter 3.3 --- Experiments --- p.25 / Chapter 3.3.1 --- Design methodology I - DSP --- p.25 / Chapter 3.3.1.1 --- Hardware platform --- p.25 / Chapter 3.3.1.2 --- Software platform --- p.26 / Chapter 3.3.1.3 --- Implementation --- p.26 / Chapter 3.3.1.4 --- Experiment and result --- p.27 / Chapter 3.3.2 --- Design methodology II ´ؤ SoC --- p.28 / Chapter 3.3.2.1 --- Hardware components --- p.28 / Chapter 3.3.2.2 --- Software components --- p.29 / Chapter 3.3.2.3 --- Implementation Department of Computer Science and Engineering --- p.29 / Chapter 3.3.2.4 --- Experiment and result --- p.30 / Chapter 3.4 --- Observation --- p.30 / Chapter 4. --- Implementation of the Device --- p.31 / Chapter 4.1 --- Choice of platforms --- p.31 / Chapter 4.2 --- Implementation Details --- p.31 / Chapter 4.2.1 --- Hardware implementation --- p.31 / Chapter 4.2.1.1 --- Atmel FingerChip --- p.32 / Chapter 4.2.1.2 --- Gemplus smart card and reader --- p.33 / Chapter 4.2.2 --- Software implementation --- p.33 / Chapter 4.2.2.1 --- Operating System --- p.33 / Chapter 4.2.2.2 --- File System --- p.33 / Chapter 4.2.2.3 --- Device Driver --- p.35 / Chapter 4.2.2.4 --- Smart card --- p.38 / Chapter 4.2.2.5 --- Fingerprint software --- p.41 / Chapter 4.2.2.6 --- Graphical user interface --- p.41 / Chapter 4.3 --- Results and observations --- p.44 / Chapter 5. --- An Application Example 一 A Penalty Ticket Payment System (PTPS) --- p.47 / Chapter 5.1 --- Requirement --- p.47 / Chapter 5.2 --- Design Principles --- p.48 / Chapter 5.3 --- Implementation --- p.52 / Chapter 5.4 --- Results and Observation --- p.57 / Chapter 6. --- Conclusions and future work --- p.62 / Chapter 7. --- References --- p.64
173

Face authentication on mobile devices: optimization techniques and applications.

January 2005 (has links)
Pun Kwok Ho. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 106-111). / Abstracts in English and Chinese. / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.1.1 --- Introduction to Biometrics --- p.1 / Chapter 1.1.2 --- Face Recognition in General --- p.2 / Chapter 1.1.3 --- Typical Face Recognition Systems --- p.4 / Chapter 1.1.4 --- Face Database and Evaluation Protocol --- p.5 / Chapter 1.1.5 --- Evaluation Metrics --- p.7 / Chapter 1.1.6 --- Characteristics of Mobile Devices --- p.10 / Chapter 1.2 --- Motivation and Objectives --- p.12 / Chapter 1.3 --- Major Contributions --- p.13 / Chapter 1.3.1 --- Optimization Framework --- p.13 / Chapter 1.3.2 --- Real Time Principal Component Analysis --- p.14 / Chapter 1.3.3 --- Real Time Elastic Bunch Graph Matching --- p.14 / Chapter 1.4 --- Thesis Organization --- p.15 / Chapter 2. --- Related Work --- p.16 / Chapter 2.1 --- Face Recognition for Desktop Computers --- p.16 / Chapter 2.1.1 --- Global Feature Based Systems --- p.16 / Chapter 2.1.2 --- Local Feature Based Systems --- p.18 / Chapter 2.1.3 --- Commercial Systems --- p.20 / Chapter 2.2 --- Biometrics on Mobile Devices --- p.22 / Chapter 3. --- Optimization Framework --- p.24 / Chapter 3.1 --- Introduction --- p.24 / Chapter 3.2 --- Levels of Optimization --- p.25 / Chapter 3.2.1 --- Algorithm Level --- p.25 / Chapter 3.2.2 --- Code Level --- p.26 / Chapter 3.2.3 --- Instruction Level --- p.27 / Chapter 3.2.4 --- Architecture Level --- p.28 / Chapter 3.3 --- General Optimization Workflow --- p.29 / Chapter 3.4 --- Summary --- p.31 / Chapter 4. --- Real Time Principal Component Analysis --- p.32 / Chapter 4.1 --- Introduction --- p.32 / Chapter 4.2 --- System Overview --- p.33 / Chapter 4.2.1 --- Image Preprocessing --- p.33 / Chapter 4.2.2 --- PCA Subspace Training --- p.34 / Chapter 4.2.3 --- PCA Subspace Projection --- p.36 / Chapter 4.2.4 --- Template Matching --- p.36 / Chapter 4.3 --- Optimization using Fixed-point Arithmetic --- p.37 / Chapter 4.3.1 --- Profiling Analysis --- p.37 / Chapter 4.3.2 --- Fixed-point Representation --- p.38 / Chapter 4.3.3 --- Range Estimation --- p.39 / Chapter 4.3.4 --- Code Conversion --- p.42 / Chapter 4.4 --- Experiments and Discussions --- p.43 / Chapter 4.4.1 --- Experiment Setup --- p.43 / Chapter 4.4.2 --- Execution Time --- p.44 / Chapter 4.4.3 --- Space Requirement --- p.45 / Chapter 4.4.4 --- Verification Accuracy --- p.45 / Chapter 5. --- Real Time Elastic Bunch Graph Matching --- p.49 / Chapter 5.1 --- Introduction --- p.49 / Chapter 5.2 --- System Overview --- p.50 / Chapter 5.2.1 --- Image Preprocessing --- p.50 / Chapter 5.2.2 --- Landmark Localization --- p.51 / Chapter 5.2.3 --- Feature Extraction --- p.52 / Chapter 5.2.4 --- Template Matching --- p.53 / Chapter 5.3 --- Optimization Overview --- p.54 / Chapter 5.3.1 --- Computation Optimization --- p.55 / Chapter 5.3.2 --- Memory Optimization --- p.56 / Chapter 5.4 --- Optimization Strategies --- p.58 / Chapter 5.4.1 --- Fixed-point Arithmetic --- p.60 / Chapter 5.4.2 --- Gabor Masks and Bunch Graphs Precomputation --- p.66 / Chapter 5.4.3 --- Improving Array Access Efficiency using ID array --- p.68 / Chapter 5.4.4 --- Efficient Gabor Filter Selection --- p.75 / Chapter 5.4.5 --- Fine Tuning System Cache Policy --- p.79 / Chapter 5.4.6 --- Reducing Redundant Memory Access by Loop Merging --- p.80 / Chapter 5.4.7 --- Maximizing Cache Reuse by Array Merging --- p.90 / Chapter 5.4.8 --- Optimization of Trigonometric Functions using Table Lookup. --- p.97 / Chapter 5.5 --- Summary --- p.99 / Chapter 6. --- Conclusions --- p.103 / Chapter 7. --- Bibliography --- p.106
174

The statistical evaluation of minutiae-based automatic fingerprint verification systems. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Basic technologies for fingerprint feature extraction and matching have been improved to such a stage that they can be embedded into commercial Automatic Fingerprint Verification Systems (AFVSs). However, the reliability of AFVSs has kept attracting concerns from the society since AFVSs do fail occasionally due to difficulties like problematic fingers, changing environments, and malicious attacks. Furthermore, the absence of a solid theoretical foundation for evaluating AFVSs prevents these failures from been predicted and evaluated. Under the traditional empirical AFVS evaluation framework, repeated verification experiments, which can be very time consuming, have to be performed to test whether an update to an AFVS can really lead to an upgrade in its performance. Also, empirical verification results are often unable to provide deeper understanding of AFVSs. To solve these problems, we propose a novel statistical evaluation model for minutiae-based AFVSs based on the understanding of fingerprint minutiae patterns. This model can predict the verification performance metrics as well as their confidence intervals. The analytical power of our evaluation model, which makes it superior to empirical evaluation methods, can assist system developers to upgrade their AFVSs purposefully. Also, our model can facilitate the theoretical analysis of the advantages and disadvantages of various fingerprint verification techniques. We verify our claims through different and extensive experiments. / Chen, Jiansheng. / "November 2006." / Adviser: Yiu-Sang Moon. / Source: Dissertation Abstracts International, Volume: 68-08, Section: B, page: 5343. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 110-122). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
175

Biometria testÃculo-epididimÃria e reserva espermÃtica ovinos (ovis aries) deslanados criados no Estado do Cearà / Biometrics testÃculo-epididimÃria sheep and reserve espermÃtica (ovis aries) deslanados created in the State of CearÃ

Alexandre Weick UchÃa Monteiro 20 March 2007 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Este trabalho teve como objetivo correlacionar parÃmetros reprodutivos de fÃcil mensuraÃÃo, que sejam representativos da capacidade reprodutiva de um macho ovino como reserva epididimÃria. Foram mensurados 38 genitais masculinos de ovinos deslanados sem padrÃo racial definido quanto os parÃmetros biomÃtricos do testÃculo e epidÃdimo comprimento, a largura, a espessura e do peso, bem como concentraÃÃo espermÃtica da cauda do epidÃdimo e volume do fluido contido da cauda. Antes do abate cada animal doador do genital teve mensurado a circunferÃncia escrotal (CE), peso e idade pela cronologia dentÃria. No tocante a reserva epididimÃria esta foi determinada pela concentraÃÃo espermÃtica do conteÃdo epididimÃrio. Todos os resultados foram expressos em media e erro padrÃo, bem como tambÃm o Coeficiente de VariaÃÃo (CV). As correlaÃÃes foram calculadas pelo mÃtodo de Pearson utilizando o procedimento âProc Corrâ do SAS (1999). Destes genitais nÃo foi observada diferenÃa (p > 0,05) entre os valores dos lados direito e esquerdo da biometria testicular. As mÃdias e erros padrÃo obtidas para PE, PT, CT, LT, ET, PTE, PCE, PCOE, PCAE, CCAE, LCAE, ECAE foram: 27,82 Â 1,77cm; 123,97 Â 26,58g; 7,83 Â 0,79cm; 5,74 Â 0,48cm; 4,57 Â 0,54cm; 18,63 Â 3,96g; 6,95 Â 1,48g; 3,45 Â 0,87g; 8,36 Â 2,13g; 3,03 Â 0,44cm; 2,22 Â 0,22cm e 1,65 Â 0,23cm respectivamente. No tocante a reserva espermÃtica da cauda do epidÃdimo, a concentraÃÃo encontrada foi de 2,47 Â 1,00 bilhÃes de sptz por mL. Das medidas biomÃtricas em estudos a que melhor se comportou nas correlaÃÃes foi o peso vivo, dos testÃculos e dos epidÃdimos mostrando sempre correlaÃÃes moderadas e significativas. O peso vivo teve correlaÃÃo mÃdia e ignificativa (p<0,0001) com as medidas biomÃtricas da cauda do epidÃdimo CCAE, LCAE e ECAE (r=0,59; r=0,60 e r= 0,59) spectivamente. A LT, comportou-se neste estudo com bom indicador do desenvolvimento testicular e epididimÃria, podendo ser extrapolado para funÃÃo reprodutiva sendo esta fortemente correlacionada com o PT (r=0,88), CE (r=0,57), PTE (r=0,60). Neste estudo a CE mostrou correlaÃÃes moderadas variando r = 0,38 a 0,69 o com as medidas testiculares e epididimÃrias e as medidas que melhor se correlacionaram foram o PT com r=0,69, CT e LT com r=0,57 respectivamente. A mensuraÃÃo CCAE foi a que apresentou melhor relaÃÃo com a grande maioria dos parÃmetros estudados, principalmente as caracterÃsticas testiculares (r= 0,54 a 0,58) e epididimÃrias (r= 0,48 a 0,73), bem como apresentou correlaÃÃo positiva e mÃdia (r=0,50) com o xv volume coletado da cauda do epidÃdimo, mostrando que esta mensuraÃÃo estar muito ligada ao desenvolvimento epididimÃrio que por conseguinte se relacionam com o desenvolvimento testicular. A CONC e VC mostraram baixas e moderadas correlaÃÃes embora positivas com as medidas testiculares e epididimÃrias. A caracterÃstica que menos se correlacionou com todas as outras mensuraÃÃes inclusive expressando coeficientes negativos foi a espessura da dobra escrotal. Contribuindo pouco quanto ao desenvolvimento testÃculo epididimÃrio e com as caracterÃsticas da reserva espermÃtica da cauda do epidÃdimo. Podemos utilizar a LT e CCAE no auxÃlio das mensuraÃÃes biometrias (Peso Vivo, PE ....) para seleÃÃo precoce de machos ovinos por sua facilidade de obtenÃÃo nos animais vivos. / The aim of this study is to correlate reproductive parameters of easy measurement to represent the reproductive capacity of a male sheep The biometric parameters of the testis and epididymis (length, midth, thickness and weight) of 38 SPRD ram were measured as well as the sperm concentration of the epididymis tail (CECE) and epididymis fluid volume (VFE) contained in the tail. The scrotal circunference (SC) and weight of each animal was measured before slaughter. The age was determined by dental chronology. The spermatozoids epididymis concentration was determined in a Neubauer chamber. All results were expressed by mean and standard deviations. The correlations were calculated by the Person method using the procedure âProc Corrâ of SAS (1999). No significant difference was observed (p>0,05) between the measured parameters of right and left sides of the testis and epididymis biometry. The means and standard deviations obtained for CE, PT, LT, ET, PTE, PCE, PCOE, PCAE, CCAE, LCAE, ECAE were:27,82 + 1,77 cm; 123,97 + 26,58 g; 7,83 + 0,79 cm; 5,74 + 0,48 cm; 4,57 + 0,54 cm; 18,63 + 3,96 g; 6,95 + 1,48 g; 3,45 + 0,87 g; 8,36 + 2,13 g; 3,03 + 0,44 cm;2,22 + 0,2 cm and 1,65 + 0,23 cm, respectively. The sperm concentration of the sperm reserve in the epididymis tail was 2,47 + 1,00 sptz billion for mL. The weight parameters (alive, of the testis and epididymis) showed moderate and significant correlations. The alive weight had medium and significant correlation (p> 0,0001) with biometrics measures of the epididymis tail:CCAE, LCAE and ECAE ( r=0,59; r=0,60 and r=0,59 respectively). LT behaved as good indicator of testis and epididymis development, and could be extrapolated with PT (r=0,88), CE (r=0,57), PTE (r=0,60). CE presented moderate correlations (r=0,38 to 0,69) varying with testis and epididymis measures, and the better correlated measures were PT with r=0,69, CT and LT with r=0,57, respectively. The CCAE parameter presented a better relationship with the majority measurements, mainly the testis (r=0,54 to 0,58) and epididymis characteristics (r=0,48 to 0,73); CCAE parameter also presented positive and moderate correlation (r=0,50) with the epididymis tail volume collected.CECE and VFE presented low and medium correlations, although positive, with the testis and epididymis measures. The characteristic less correlated with all the others measurements, besides the ones expressing negative coefficients, was the thickness of the scrotal fold. The LT and CCAE parameters can be included in the biometry measurements (Live Weight, PEâ) of the male reproductive tract to help the precocious selection of male sheep.
176

Extracting fingerprint features using textures.

Mackley, Joshua, mikewood@deakin.edu.au January 2004 (has links)
Personal identification of individuals is becoming increasingly adopted in society today. Due to the large number of electronic systems that require human identification, faster and more secure identification systems are pursued. Biometrics is based upon the physical characteristics of individuals; of these the fingerprint is the most common as used within law enforcement. Fingerprint-based systems have been introduced into the society but have not been well received due to relatively high rejection rates and false acceptance rates. This limited acceptance of fingerprint identification systems requires new techniques to be investigated to improve this identification method and the acceptance of the technology within society. Electronic fingerprint identification provides a method of identifying an individual within seconds quickly and easily. The fingerprint must be captured instantly to allow the system to identify the individual without any technical user interaction to simplify system operation. The performance of the entire system relies heavily on the quality of the original fingerprint image that is captured digitally. A single fingerprint scan for verification makes it easier for users accessing the system as it replaces the need to remember passwords or authorisation codes. The identification system comprises of several components to perform this function, which includes a fingerprint sensor, processor, feature extraction and verification algorithms. A compact texture feature extraction method will be implemented within an embedded microprocessor-based system for security, performance and cost effective production over currently available commercial fingerprint identification systems. To perform these functions various software packages are available for developing programs for windows-based operating systems but must not constrain to a graphical user interface alone. MATLAB was the software package chosen for this thesis due to its strong mathematical library, data analysis and image analysis libraries and capability. MATLAB enables the complete fingerprint identification system to be developed and implemented within a PC environment and also to be exported at a later date directly to an embedded processing environment. The nucleus of the fingerprint identification system is the feature extraction approach presented in this thesis that uses global texture information unlike traditional local information in minutiae-based identification methods. Commercial solid-state sensors such as the type selected for use in this thesis have a limited contact area with the fingertip and therefore only sample a limited portion of the fingerprint. This limits the number of minutiae that can be extracted from the fingerprint and as such limits the number of common singular points between two impressions of the same fingerprint. The application of texture feature extraction will be tested using variety of fingerprint images to determine the most appropriate format for use within the embedded system. This thesis has focused on designing a fingerprint-based identification system that is highly expandable using the MATLAB environment. The main components that are defined within this thesis are the hardware design, image capture, image processing and feature extraction methods. Selection of the final system components for this electronic fingerprint identification system was determined by using specific criteria to yield the highest performance from an embedded processing environment. These platforms are very cost effective and will allow fingerprint-based identification technology to be implemented in more commercial products that can benefit from the security and simplicity of a fingerprint identification system.
177

Iris recognition using standard cameras

Holmberg, Hans January 2006 (has links)
<p>This master thesis evaluates the use of off-the-shelf standard cameras for biometric identification of the human iris. As demands on secure identification are constantly rising and as the human iris provides with a pattern that is excellent for identification, the use of inexpensive equipment could help iris recognition become a new standard in security systems. To test the performance of such a system a review of the current state of the research in the area was done and the most promising methods were chosen for evaluation. A test environment based on open source code was constructed to measure the performance of iris recognition methods, image quality and recognition rate.</p><p>In this paper the image quality of a database consisting of images from a standard camera is assessed, the most important problem areas identified, and the overall recognition performance measured. Iris recognition methods found in literature are tested on this class of images. These together with newly developed methods show that a system using standard equipment can be constructed. Tests show that the performance of such a system is promising.</p>
178

Towards Template Security for Iris-based Biometric Systems

Fouad, Marwa 18 April 2012 (has links)
Personal identity refers to a set of attributes (e.g., name, social insurance number, etc.) that are associated with a person. Identity management is the process of creating, maintaining and destroying identities of individuals in a population. Biometric technologies are technologies developed to use statistical analysis of an individual’s biological or behavioral traits to determine his identity. Biometrics based authentication systems offer a reliable solution for identity management, because of their uniqueness, relative stability over time and security (among other reasons). Public acceptance of biometric systems will depend on their ability to ensure robustness, accuracy and security. Although robustness and accuracy of such systems are rapidly improving, there still remain some issues of security and balancing it with privacy. While the uniqueness of biometric traits offers a convenient and reliable means of identification, it also poses the risk of unauthorized cross-referencing among databases using the same biometric trait. There is also a high risk in case of a biometric database being compromised, since it’s not possible to revoke the biometric trait and re-issue a new one as is the case with passwords and smart keys. This unique attribute of biometric based authentication system poses a challenge that might slow down public acceptance and the use of biometrics for authentication purposes in large scale applications. In this research we investigate the vulnerabilities of biometric systems focusing on template security in iris-based biometric recognition systems. The iris has been well studied for authentication purposes and has been proven accurate in large scale applications in several airports and border crossings around the world. The most widely accepted iris recognition systems are based on Daugman’s model that creates a binary iris template. In this research we develop different systems using watermarking, bio-cryptography as well as feature transformation to achieve revocability and security of binary templates in iris based biometric authentication systems, while maintaining the performance that enables widespread application of these systems. All algorithms developed in this research are applicable on already existing biometric authentication systems and do not require redesign of these existing, well established iris-based authentication systems that use binary templates.
179

Fingerprints recognition

Dimitrov, Emanuil January 2009 (has links)
Nowadays biometric identification is used in a variety of applications-administration, business and even home. Although there are a lot of biometric identifiers, fingerprints are the most widely spread due to their acceptance from the people and the cheap price of the hardware equipment. Fingerprint recognition is a complex image recognition problem and includes algorithms and procedures for image enhancement and binarization, extracting and matching features and sometimes classification. In this work the main approaches in the research area are discussed, demonstrated and tested in a sample application. The demonstration software application is developed by using Verifinger SDK and Microsoft Visual Studio platform. The fingerprint sensor for testing the application is AuthenTec AES2501.
180

Fingerprint Segmentation

Jomaa, Diala January 2009 (has links)
In this thesis, a new algorithm has been proposed to segment the foreground of the fingerprint from the image under consideration. The algorithm uses three features, mean, variance and coherence. Based on these features, a rule system is built to help the algorithm to efficiently segment the image. In addition, the proposed algorithm combine split and merge with modified Otsu. Both enhancements techniques such as Gaussian filter and histogram equalization are applied to enhance and improve the quality of the image. Finally, a post processing technique is implemented to counter the undesirable effect in the segmented image. Fingerprint recognition system is one of the oldest recognition systems in biometrics techniques. Everyone have a unique and unchangeable fingerprint. Based on this uniqueness and distinctness, fingerprint identification has been used in many applications for a long period. A fingerprint image is a pattern which consists of two regions, foreground and background. The foreground contains all important information needed in the automatic fingerprint recognition systems. However, the background is a noisy region that contributes to the extraction of false minutiae in the system. To avoid the extraction of false minutiae, there are many steps which should be followed such as preprocessing and enhancement. One of these steps is the transformation of the fingerprint image from gray-scale image to black and white image. This transformation is called segmentation or binarization. The aim for fingerprint segmentation is to separate the foreground from the background. Due to the nature of fingerprint image, the segmentation becomes an important and challenging task. The proposed algorithm is applied on FVC2000 database. Manual examinations from human experts show that the proposed algorithm provides an efficient segmentation results. These improved results are demonstrating in diverse experiments.

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