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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

Unconstrained face recognition for law enforcement applications

Singh, Richa, January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vii, 57 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 53-57).
2

The paranasal air sinuses in the human : an anatomical assessment using helical multislice computed tomography : applications to human forensic identification

Fernandes, Carmen Lee January 2018 (has links)
Introduction: Forensic pathologists may be asked to identify the race group or sex of a cranium of unknown origin. Race group refers to geographic ancestry and sex is biological sex. An analysis of the volumes and measurements of human paranasal sinuses, namely maxillary, ethmoid, sphenoid and frontal sinuses, in dried crania of different race and sex groups (European and Zulu male and female) was undertaken to search for a new improved approach of classifying crania according to race and sex. This anatomical assessment of the human paranasal sinuses identifies race and sex variations in the paranasal sinuses. Variations in paranasal sinus volumes and measurements may mean a variation in anatomical landmarks. The best combination of sinus measurements was selected to classify a cranium according to race group and sex making this research relevant to the field of forensic medicine. Objectives: To compare the paranasal sinus volumes and measurements of dried crania of European and Zulu descent with respect to race group and sex and to develop a method of classifying a cranium according to race group or sex by using dimensions of the paranasal sinuses. Methodology: Documented, cadaver derived, dried crania were obtained from the Raymond A. Dart Collection of Human Skeletons, housed at the School of Anatomical Sciences at the University of the Witwatersrand, Johannesburg, South Africa. Age, race and sex were recorded for each cranium within the collection and hence within the study sample. 26 Adult European crania; 13 male, 13 female. Age range 19-75yrs (mean 49.42yrs) and 27 Adult Zulu crania: 13 male, 14 female. Age range 16-90yrs (mean 40.16yrs) was selected for this study. An additional cranium of unknown origin was also analysed in the research. European crania were from descendants of Europe living in South Africa and Zulu crania were obtained from Zulu patients who were part of the Zulu tribe of South Africa. 53 crania with intact paranasal sinuses (106 individual sinuses for each of the maxillary, ethmoid, sphenoid and frontal sinuses) were studied. In addition, 2 sinuses from the unknown cranium were analysed. The dried crania of European and Zulu origin were assessed by helical, multislice computed tomography using 1mm coronal slices. The area for each slice was obtained by tracing the outline of each slice. A volume was calculated by the CT machine that totaled the slices for each sinus. Measurements of width, length and height were also assessed, as were other craniometrical measurements. Statistical analysis was performed for all European and Zulu male and female sinuses in respect of volumes and measurements. Further statistical analysis searched for classification patterns. In addition, forty patients' scans from the European and Zulu male and female groups in Southern Africa were also assessed. CT scans of 10 adult European males, 10 adult European females, 10 adult Zulu males and 10 adult Zulu females provided 40 pairs of maxillary, ethmoid, sphenoid and frontal sinuses for analysis. Europeans were South African persons of European descent and Zulus were from the Zulu tribe of Kwa Zulu Natal in South Africa. Results: The aim of identifying race and sex differences in this anatomical region is achieved. Significant race and sex variations were found in the European and Zulu, male and female groups when analysing the volumes and measurements of the paranasal sinuses. The very best combinations of classifiable measurements were described and are being put forward as a new tool in human forensic identification studies. The significant sex classification figure of 91.8% by combining ethmoid, sphenoid and frontal paranasal sinus measurements, is a new discovery for using a combination of the sinuses. The significant race classification figure of 95.9 % is an excellent classification figure for classification according to race. This was done using the measurements of maxillary, ethmoid and total distance across the sinuses. All this was achieved by using the measurements of the paranasal sinuses in a European and Zulu, male and female population. Conclusion: Forensic race and sex identification of crania is now possible using a combination of measurements from the paranasal sinuses. A new approach to classifying a cranium into an race or sex group is revealed by way of using a new combination of paranasal sinus measurements. This discovery is of importance to forensic medicine in the realm of identification as it provides a measurable way of assigning race or sex to a cranium within a particular region. Other studies based on other race groups may add further value. What is clear is that the paranasal sinuses are now of established value when assessing race or sex group of a unknown cranium. A new tool for forensic race and sex identification is provided to the armamentarium of the forensic pathologist and associated disciplines.
3

Adaptive frame selection for enhanced face recognition in low-resolution videos

Jillela, Raghavender Reddy. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains viii, 67 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 62-67).
4

Feature level fusion in multimodal biometrics

Govindarajan, Rohin K. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiii, 107 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 101-107).
5

Estimating sexual dimorphism from sternal rib ends /

Gavit, Kristina Rhea, January 1900 (has links)
Thesis (M.A.)--Texas State University--San Marcos, 2009. / Vita. Appendix: leaves 28-40. Includes bibliographical references (leaves 41-43). Also available on microfilm.
6

Estimation of image quality factors for face recognition

Akinbola, Akintunde A. January 2005 (has links)
Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains vi, 56 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 52-56).
7

Human Activity Recognition and Pathological Gait Pattern Identification

Niu, Feng 14 December 2007 (has links)
Human activity analysis has attracted great interest from computer vision researchers due to its promising applications in many areas such as automated visual surveillance, computer-human interactions, and motion-based identification and diagnosis. This dissertation presents work in two areas: general human activity recognition from video, and human activity analysis for the purpose of identifying pathological gait from both 3D captured data and from video. Even though the research in human activity recognition has been going on for many years, still there are many issues that need more research. This includes the effective representation and modeling of human activities and the segmentation of sequences of continuous activities. In this thesis we present an algorithm that combines shape and motion features to represent human activities. In order to handle the activity recognition from any viewing angle we quantize the viewing direction and build a set of Hidden Markov Models (HMMs), where each model represents the activity from a given view. Finally, a voting based algorithm is used to segment and recognize a sequence of human activities from video. Our method of representing activities has good attributes and is suitable for both low resolution and high resolution video. The voting based algorithm performs the segmentation and recognition simultaneously. Experiments on two sets of video clips of different activities show that our method is effective. Our work on identifying pathological gait is based on the assumption of gait symmetry. Previous work on gait analysis measures the symmetry of gait based on Ground Reaction Force data, stance time, swing time or step length. Since the trajectories of the body parts contain information about the whole body movement, we measure the symmetry of the gait based on the trajectories of the body parts. Two algorithms, which can work with different data sources, are presented. The first algorithm works on 3D motion-captured data and the second works on video data. Both algorithms use support vector machine (SVM) for classification. Each of the two methods has three steps: the first step is data preparation, i.e., obtaining the trajectories of the body parts; the second step is gait representation based on a measure of gait symmetry; and the last step is SVM based classification. For 3D motion-captured data, a set of features based on Discrete Fourier Transform (DFT) is used to represent the gait. We demonstrate the accuracy of the classification by a set of experiments that shows that the method for 3D motion-captured data is highly effective. For video data, a model based tracking algorithm for human body parts is developed for preparing the data. Then, a symmetry measure that works on the sequence of 2D data, i.e. sequence of video frames, is derived to represent the gait. We performed experiments on both 2D projected data and real video data to examine this algorithm. The experimental results on 2D projected data showed that the presented algorithm is promising for identifying pathological gait from video. The experimental results on the real video data are not good as the results on 2D projected data. We believe that better results could be obtained if the accuracy of the tracking algorithm is improved.
8

Biometric system security and privacy: data reconstruction and template protection

Mai, Guangcan 31 August 2018 (has links)
Biometric systems are being increasingly used, from daily entertainment to critical applications such as security access and identity management. It is known that biometric systems should meet the stringent requirement of low error rate. In addition, for critical applications, the security and privacy issues of biometric systems are required to be concerned. Otherwise, severe consequence such as the unauthorized access (security) or the exposure of identity-related information (privacy) can be caused. Therefore, it is imperative to study the vulnerability to potential attacks and identify the corresponding risks. Furthermore, the countermeasures should also be devised and patched on the systems. In this thesis, we study the security and privacy issues in biometric systems. We first make an attempt to reconstruct raw biometric data from biometric templates and demonstrate the security and privacy issues caused by the data reconstruction. Then, we make two attempts to protect biometric templates from being reconstructed and improve the state-of-the-art biometric template protection techniques.
9

A new approach to automatic saliency identification in images based on irregularity of regions

Al-Azawi, Mohammad Ali Naji Said January 2015 (has links)
This research introduces an image retrieval system which is, in different ways, inspired by the human vision system. The main problems with existing machine vision systems and image understanding are studied and identified, in order to design a system that relies on human image understanding. The main improvement of the developed system is that it uses the human attention principles in the process of image contents identification. Human attention shall be represented by saliency extraction algorithms, which extract the salient regions or in other words, the regions of interest. This work presents a new approach for the saliency identification which relies on the irregularity of the region. Irregularity is clearly defined and measuring tools developed. These measures are derived from the formality and variation of the region with respect to the surrounding regions. Both local and global saliency have been studied and appropriate algorithms were developed based on the local and global irregularity defined in this work. The need for suitable automatic clustering techniques motivate us to study the available clustering techniques and to development of a technique that is suitable for salient points clustering. Based on the fact that humans usually look at the surrounding region of the gaze point, an agglomerative clustering technique is developed utilising the principles of blobs extraction and intersection. Automatic thresholding was needed in different stages of the system development. Therefore, a Fuzzy thresholding technique was developed. Evaluation methods of saliency region extraction have been studied and analysed; subsequently we have developed evaluation techniques based on the extracted regions (or points) and compared them with the ground truth data. The proposed algorithms were tested against standard datasets and compared with the existing state-of-the-art algorithms. Both quantitative and qualitative benchmarking are presented in this thesis and a detailed discussion for the results has been included. The benchmarking showed promising results in different algorithms. The developed algorithms have been utilised in designing an integrated saliency-based image retrieval system which uses the salient regions to give a description for the scene. The system auto-labels the objects in the image by identifying the salient objects and gives labels based on the knowledge database contents. In addition, the system identifies the unimportant part of the image (background) to give a full description for the scene.
10

Emprego de miniSTRs \"non-CODIS\" em amostras biológicas de DNA forense. / The use of \"non-CODIS\" miniSTRS in forensic DNA biological samples.

Pacheco, Ana Claudia 15 December 2010 (has links)
Foram analisadas 80 amostras de casos forenses criminais do Laboratório de DNA do Instituto de Criminalística de São Paulo. O DNA foi extraído de materiais cadavéricos, vestígios de crimes sexuais e de locais de crimes. A quantificação se deu por PCR em tempo real e a amplificação por PCR, em 2 reações triplex, dos miniSTRs non-CODIS D10S1248, D14S1434 e D22S1045 (NCO01) e D1S1677, D2S441 e D4S2364 (NCO02), com posterior eletroforese capilar para detecção dos produtos fluorescentes. Avaliou-se o grau de conservação das amostras e a qualidade dos perfis genéticos obtidos. Houve concordância nas dificuldades entre diferentes amostras quando comparado com as abordagens tradicionais. Confirmou-se a sensibilidade e robustez dos sistemas utilizados, bem como a vantagem em se aumentar o número de regiões analisadas, principalmente em casos complexos, mas foram constatadas desvantagens de procedimentos tipo in-house. É necessário o estudo das frequências alélicas destes loci para a população brasileira, que possam ser incorporadas nos cálculos estatísticos dos laudos. / 80 forensic casework samples from the DNA Laboratory of the Criminalistics Institute of São Paulo were analyzed. DNA was extracted from corpse, sexual assault and crime scene evidence. The extractions were quantified using real-time PCR, amplified by two triplex PCR reactions of the non-CODIS miniSTRs D10S1248, D14S1434, D22S1045 (NC01) and D1S1677, D2S441, D4S2364 (NC02), followed by capillary electrophoresis to detect the fluorescent products. The sample preservation and quality of the genetic profiles obtained were evaluated. The results were compared to the previous obtained with the routine techniques employed in the laboratory and there was concordance in the relative difficulties. The sensibility and robustness of the systems employed were confirmed, as well as the advantages in increasing the number of loci studied, mainly in complex cases, although the in-house procedures were considered a disadvantage. The establishment of brazilian population allele frequencies for these loci is necessary for the statistical calculations of the forensic reports.

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