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Výzkum systému GPS pro lokalizaci bezdrátových senzorových uzlů / Research into GPS system used for Wireless Sensor Node LocalizationJuračka, Jan January 2013 (has links)
Theme of the thesis is research and possibility of using GPS system from localization in wireless sensor network. Paper deals with the accuracy and energy consumption of GPS localization. Thesis also solve using of localization in local anchor system. Theoretical part describes IEEE 802.15.4 standard, capability of used nodes and describe ways how to use RSSI value to resolve location
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Multimodální biometrický systém kombinující duhovku a sítnici / Multibiometric System Combining Iris and RetinaJanečka, Petr January 2015 (has links)
This diploma thesis focuses on multibiometric systems, specifically on biometric fusion. The thesis describes eye biometrics, i.e. recognition based on retina and iris. The key part consists of design and implementation specification of a biometric system based on retina and iris recognition.
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Použití inteligentních agentů v bezdrátových senzorových sítích / Usage of Intelligent Agents in Wireless Sensor NetworksŽídek, Petr January 2011 (has links)
This thesis is focused on wireless sensor networks and implementation tools for creation and simulation of applications. It describes WSnageNt project, which is intended to support agents in wireless sensor networks. The main objective of this thesis is to extend the WSageNt project with new features that will allow to create agents with more capabilities. These features will be then used to extend the WSageNt project with network node movement tracking capability.
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Iris Biometric Identification Using Artificial Neural NetworksHaskett, Kevin Joseph 01 August 2018 (has links)
A biometric method is a more secure way of personal identification than passwords. This thesis examines the iris as a personal identifier with the use of neural networks as the classifier. A comparison of different feature extraction methods that include the Fourier transform, discrete cosine transform, the eigen analysis method, and the wavelet transform, is performed. The robustness of each method, with respect to distortion and noise, is also studied.
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Integrating biometric authentication into multiple applicationsBreedt, Morne 28 August 2007 (has links)
The Internet has grown from its modest academic beginnings into an important, global communication medium. It has become a significant, intrinsic part of our lives, how we distribute information and how we transact. It is used for a variety of purposes, including: banking; home shopping; commercial trade - using EDI (Electronic Data Interchange); and to gather information for market research and other activities. Owing to its academic origins, the early developers of the Internet did not focus on security. However, now that it has rapidly evolved into an extensively used, global commercial transaction and distribution channel, security has become a big concern. Fortunately, the field of information security has started to evolve in response and is fast becoming an important discipline with a sound theoretical basis. The discipline views the twin processes of identification and authentication as crucial aspects of information security. An individual access attempt must be identifiable prior to access being authorised otherwise system confidentiality cannot be enforced nor integrity safeguarded. Similarly, non-denial becomes impossible to instigate since the system is unable to log an identity against specific transactions. Consequently, identification and authentication should always be viewed as the first step to successfully enforcing information security. The process of identification and authorisation is, in essence, the ability to prove or verify an identity. This is usually accomplished using either one or a combination of the following three traditional identification techniques: something you possess; something you know; or something you are. A critical consideration when designing an application is which identification method, or combination of methods, from the three described above to use. Each method offers its own pros and cons and there are many ways to compare and contrast them. The comparison made in this study identifies biometrics as the best solution in a distributed application environment. There are, however, two over-arching hindrances to its widespread adoption. The first is the environment’s complexity - with multiple applications being accessed by both the public and the private sectors - and the second is that not all biometrics are popular and no single method has universe appeal. The more significant hindrance of the two is the latter, that of acceptance and trust, because it matters little how good or efficient a system is if nobody is willing to use it. This observation suggests that the identification system needs to be made as flexible as possible. In a democratic society, it could be argued that the best way of ensuring the successful adoption of a biometric system would be to allow maximum freedom of choice and let users decide which biometric method they would like to use. Although this approach is likely to go a long way towards solving the acceptance issue, it increases the complexity of the environment significantly. This study attempts to solve this problem by reducing the environment’s complexity while simultaneously ensuring the user retains maximum biometric freedom of choice. This can be achieved by creating a number of central biometric repositories. Each repository would be responsible for maintaining a biometric template data store for a type of biometric. These repositories or “Biometric Authorities” would act as authentication facilitators for a wide variety of applications and free them from that responsibility. / Dissertation (MSc (Computer Engineering))--University of Pretoria, 2005. / Electrical, Electronic and Computer Engineering / MSc / unrestricted
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Effect of Neurturin Deficiency on Cholinergic and Catecholaminergic Innervation of the Murine EyeHoover, Jeffrey L., Bond, Cherie E., Hoover, Donald B., Defoe, Dennis M. 01 January 2014 (has links)
Neurturin (NRTN) is a neurotrophic factor required for the development of many parasympathetic neurons and normal cholinergic innervation of the heart, lacrimal glands and numerous other tissues. Previous studies with transgenic mouse models showed that NRTN is also essential for normal development and function of the retina (J. Neurosci. 28:4123-4135, 2008). NRTN knockout (KO) mice exhibit a marked thinning of the outer plexiform layer (OPL) of the retina, with reduced abundance of horizontal cell dendrites and axons, and aberrant projections of horizontal cells and bipolar cells into the outer nuclear layer. The effects of NRTN deletion on specific neurotransmitter systems in the retina and on cholinergic innervation of the iris are unknown. To begin addressing this deficiency, we used immunohistochemical methods to study cholinergic and noradrenergic innervation of the iris and the presence and localization of cholinergic and dopaminergic neurons and nerve fibers in eyes from adult male wild-type (WT) and NRTN KO mice (age 4-6 months). Mice were euthanized, and eyes were removed and fixed in cold neutral buffered formalin or 4% paraformaldehyde. Formalin-fixed eyes were embedded in paraffin, and 5μm cross-sections were collected. Representative sections were stained with hematoxylin and eosin or processed for fluorescence immunohistochemistry after treatment for antigen retrieval. Whole mount preparations were dissected from paraformaldehyde fixed eyes and used for immunohistochemistry. Cholinergic and catecholaminergic nerve fibers were labeled with primary antibodies to the vesicular acetylcholine transporter (VAChT) and tyrosine hydroxylase (TH), respectively. Cholinergic and dopaminergic cell bodies were labeled with antibodies to choline acetyltransferase (ChAT) and TH, respectively. Cholinergic innervation of the mouse iris was restricted to the sphincter region, and noradrenergic fibers occurred throughout the iris and in the ciliary processes. This pattern was unaffected by deletion of NRTN. Furthermore, functional experiments demonstrated that cholinergic regulation of the pupil diameter was retained in NRTN KO mice. Hematoxylin and eosin stains of the retina confirmed a marked thinning of the OPL in KO mice. VAChT and ChAT staining of the retina revealed two bands of cholinergic processes in the inner plexiform layer, and these were unaffected by NRTN deletion. Likewise, NRTN deletion did not affect the abundance of ChAT-positive ganglion and amacrine cells. In marked contrast, staining for TH showed an increased abundance of dopaminergic processes in the OPL of retina from KO mice. Staining of retinal whole mounts for TH showed no difference in the abundance of dopaminergic amacrine cells between WT and KO mice. These findings demonstrate that the neurotrophic factor NRTN is not required for the development or maintenance of cholinergic innervation of the iris, cholinergic control of pupil diameter, or for development of cholinergic and dopaminergic amacrine cells of the retina. However, NRTN deficiency causes a marked reduction in the size of the OPL and aberrant growth of dopaminergic processes into this region.
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Postmortem iris recognition and its application in human identificationSansola, Alora 03 November 2015 (has links)
Iris recognition is a validated and non-invasive human identification technology currently implemented for the purposes of surveillance and security (i.e. border control, schools, military). Similar to deoxyribonucleic acid (DNA), irises are a highly individualizing component of the human body. Based on a lack of genetic penetrance, irises are unique between an individual’s left and right iris and between identical twins, proving to be more individualizing than DNA.
At this time, little to no research has been conducted on the use of postmortem iris scanning as a biometric measurement of identification. The purpose of this pilot study is to explore the use of iris recognition as a tool for postmortem identification. Objectives of the study include determining whether current iris recognition technology can locate and detect iris codes in postmortem globes, and if iris scans collected at different postmortem time intervals can be identified as the same iris initially enrolled.
Data from 43 decedents involving 148 subsequent iris scans demonstrated a subsequent match rate of approximately 80%, supporting the theory that iris recognition technology is capable of detecting and identifying an individual’s iris code in a postmortem setting. A chi-square test of independence showed no significant difference between match outcomes and the globe scanned (left vs. right), and gender had no bearing on the match outcome. There was a significant relationship between iris color and match outcome, with blue/gray eyes yielding a lower match rate (59%) compared to brown (82%) or green/hazel eyes (88%), however, the sample size of blue/gray eyes in this study was not large enough to draw a meaningful conclusion. An isolated case involving an antemortem initial scan collected from an individual on life support yielded an accurate identification (match) with a subsequent scan captured at approximately 10 hours postmortem.
Falsely rejected subsequent iris scans or "no match" results occurred in about 20% of scans; they were observed at each PMI range and varied from 19-30%. The false reject rate is too high to reliably establish non-identity when used alone and ideally would be significantly lower prior to implementation in a forensic setting; however, a "no match" could be confirmed using another method. Importantly, the data showed a false match rate or false accept rate (FAR) of zero, a result consistent with previous iris recognition studies in living individuals.
The preliminary results of this pilot study demonstrate a plausible role for iris recognition in postmortem human identification. Implementation of a universal iris recognition database would benefit the medicolegal death investigation and forensic pathology communities, and has potential applications to other situations such as missing persons and human trafficking cases.
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Enhancing Our Genetic Knowledge of Human Iris Pigmentation and Facial MorphologyEller, Ryan 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / The biological underpinnings that control iris pigmentation and facial morphology are two areas of research that over the last decade are becoming more thoroughly investigated due to the increased affordability of genotyping and advances in technology allowing for more advanced analysis techniques. Despite the ease of access to the data and the tools required to perform iris pigmentation and facial morphological studies, there are still numerous challenges researchers must overcome when exploring the genetics of these complex phenotypes. Some of these challenges include difficulty in working with the bioinformatic programs designed to analyze genetic associations, the inability to define a phenotype that captures the true nature of these traits, and analysis techniques that fail to model complex gene-gene interactions and their effect on a phenotype or phenotypes of interest. In this body of work, I attempted to address these challenges by designing a bioinformatic pipeline, Odyssey, that bridges the communication gaps between various data preparation programs and the programs that analyze genomic data. With this program, genome-wide association studies (GWAS) could be conducted in a quicker, more efficient, and easier manner. I also redefined iris color as a quantitative measurement of pre-defined color classes. In this way it is possible to define and quantify the unique and intricate mixtures of color, which allows for the identification of known and novel variants that affect individual iris color. I also improved upon current prediction models by developing a neural network model capable of predicting a quantitative output to four pre-defined classes; blue/grey, light brown (hazel), perceived green, and dark brown. I examined the effects of defining a simple facial morphology phenotype that more accurately captures the lower face and jaw shape. I then analyzed this phenotype via a GWAS and found several novel variants that may be associated with a square and diamond shaped face. Lastly, I demonstrated that structural equation modeling can be used in combination with traditional GWAS to examine interactions amongst associated variants, which unearths potential biological relationships that impact the multifaceted phenotype of facial morphology.
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Security Enhancement of Over-The-Air Update for Connected VehiclesChawan, Akshay January 2018 (has links)
No description available.
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Using synthetic images to improve iris biometric performanceHasegawa, Robert Shigehisa 01 January 2012 (has links) (PDF)
The rapid advance of information technology has allowed for a rise in the use of biometric markers to automatically track the identity of individuals. Iris biometrics has emerged as one of the most reliable and accurate systems when dealing with cooperating subjects, however, challenges arise when attempting to minimize the amount of intrusion when examining subjects. Allowing for more flexibility in data capture settings will introduce differences in the iris texture due to changes in ambient light, which may negatively impact recognition results. This research examines the feasibility of using 3D software to synthetically dilate the pupils of existing iris images to more closely match the size of a target image. Methods are developed first to evaluate the compatibility of synthetic images with iris identification software, and then to examine what specific areas of the iris texture differ between synthetic and real images. Results show synthetic images are found to be compatible with the recognition process and have the potential to improve performance.
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