The Space Flight Lab (SFL) at the University of Toronto Institute for Aerospace Studies (UTIAS) has developed an ambitious satellite program called the Canadian Advanced Nanospace eXperiment (CanX). The newest generation of CanX missions are based on the Generic Nanosatellite Bus (GNB). This bus was designed to accommodate many missions using a single, common platform. Currently, there are three nanosatellite missions using the GNB design. These missions include AISSat-1, CanX-3 (BRITE) and CanX-4&5. This thesis describes the high level embedded software design for the on-board computer (OBC), as part of the generic nanosatellite bus. The software discussed includes the Universal Asynchronous Receiver/Transmitter (UART) Thread, Serial Communications Controller (SCC) Thread, Inter-Integrated Circuit (I2C) Thread, Serial Peripheral Interface (SPI) Thread, Communications Thread, Memory Management Thread, Power Thread, House Keeping Computer (HKC) Thread, AISSat-1 Payload Thread and the Time Tag Thread. In addition to the application threads mentioned above, the software design and validation of the On Board Computer (OBC) design for the AISSat-1 mission is also discussed.

The Space Flight Lab (SFL) at the University of Toronto Institute for Aerospace Studies (UTIAS) has developed an ambitious satellite program called the Canadian Advanced Nanospace eXperiment (CanX). The newest generation of CanX missions are based on the Generic Nanosatellite Bus (GNB). This bus was designed to accommodate many missions using a single, common platform. Currently, there are three nanosatellite missions using the GNB design. These missions include AISSat-1, CanX-3 (BRITE) and CanX-4&5. This thesis describes the high level embedded software design for the on-board computer (OBC), as part of the generic nanosatellite bus. The software discussed includes the Universal Asynchronous Receiver/Transmitter (UART) Thread, Serial Communications Controller (SCC) Thread, Inter-Integrated Circuit (I2C) Thread, Serial Peripheral Interface (SPI) Thread, Communications Thread, Memory Management Thread, Power Thread, House Keeping Computer (HKC) Thread, AISSat-1 Payload Thread and the Time Tag Thread. In addition to the application threads mentioned above, the software design and validation of the On Board Computer (OBC) design for the AISSat-1 mission is also discussed.

The wireless world of today is essential to the everyday life of millions of people. Wireless technology is evolving at a rapid pace that's speed outmatches what the previous testing can handle. This necessitates the need for smarter and faster testing methods. One of the recent fast and efficient testing methods is fuzz testing. Fuzz testing is the generation and injection of unexpected input called "fuzzed" input for a system by slightly changing a base input hundreds or even thousands of times and introducing each change into a system to observe its effects. In this thesis, we developed and implemented a fuzz testing architecture to test 5G wireless system vulnerabilities. The proposed design uses multiple open-source software to create a virtual wireless environment for testing the fuzzed inputs' effects on the wireless attach procedure. Having an accessible and adaptable fuzzing architecture to use with wireless networks will help against malicious parties. Due to 5G simulation technology still being developed and the cost of ready-made 5G testing equipment, the architecture was implemented in an LTE environment using the srsRAN LTE simulation software, the Boofuzz fuzzing software, and Wireshark packet capture software. The results show consistent effects of the fuzz testing on the outputs of the LTE eNB. We also include a discussion of our future suggestions to improve the proposed fuzzing architecture. / Master of Science / The persistence of the cellular network is essential to the everyday life of millions of people. Cell phones and cell towers play an important role in business, communication, and recreation across the globe. The speed of advancements made in phones and cell towers technology is outpacing the speed of security testing, increasing the possibility of system vulnerabilities and unexplored back-doors. To cover the security testing gap, different automated testing models are being researched and developed, one of which is fuzz testing. Fuzz testing is the generation and injection of unexpected input called "fuzzed" input for a system by slightly changing a base input hundreds or even thousands of times and introducing each change into a system to observe its effects. The fuzzing architecture proposed in this thesis is used to test for security flaws in wireless cellular networks. We implemented our fuzz testing model in a simulated 4G cellular network, where the results show the effectiveness of the model on tracing network vulnerabilities. The results of the experiment show consistent effects of the fuzz testing on a wireless system. A discussion of how the proposed model can be further improved for future work is added to the end of this thesis.

La schizophrénie est une pathologie sévère et fréquente. Elle constitue un problème majeur de santé publique. Les traitements disponibles présentent des problèmes de tolérance non négligeables et leur efficacité reste modérée. La recherche en pharmacogénétique des antipsychotiques a pour objectif d’aider les prescripteurs à choisir les traitements de façon plus rationnelle. Les carences méthodologiques des premières études réalisées expliquent sans doute le peu de résultat répliqué à ce jour. Dans une cohorte de patients schizophrènes caucasiens traités par olanzapine ou rispéridone et évaluée prospectivement pour l’efficacité et la tolérance du traitement, nous avons d’abord recherché des critères cliniques permettant de prédire la réponse au traitement. L’age précoce de début des troubles et la durée de la maladie sont des prédicteurs individuels de la mauvaise réponse au traitement. Nous avons également étudié l’implication de variants génétiques du transporteur de la noradrénaline dans l’efficacité des traitements. Nous avons observé l’implication de deux polymorphismes dans la décroissance des symptômes positifs sous traitement. L’analyse de l’impact du variant C825T de la GNB3 dans la prise de poids sous antipsychotique n’a pas retrouvé d’association significative. Enfin, nous avons étudié l’ensemble des variants alléliques du cytochrome P450 2D6 dans cette cohorte de patients schizophrènes comparée à des témoins. L’allèle CYP2D6*2 était associé à un effet protecteur vis à vis de la schizophrénie. Les associations retrouvées devraient aider à mieux comprendre les mécanismes physiopathologiques impliqués dans la schizophrénie et la réponse au traitement / Schizophrenia is a frequent and severe disease. It constitutes a major public health problem. All the available treatments however, have significant adverse side-effects and their efficacy remains moderate. The aim of pharmacogenetic research is to help practitioners to choose treatments in a more rational way. The methodological limits of the first published studies probably explain the lack of replication of such studies. In a prospective study of a sample of Caucasian schizophrenic patients treated with olanzapine or risperidone, clinical criteria were assessed as factors that may predict drug response. Early onset and duration of the disease, individually predicted an unfavourable drug response. We also studied genetic variants of the norepinephrine transporter to see how they may affect antipsychotic drug efficacy. Two polymorphisms were associated with a reduction in positive symptoms in treated schizophrenic patients. No association between the GBN3 C825T variant and weight gain in patients treated by antispychotic drugs was observed. Finally, we genotyped all the cytochrome P450 2D6 allelic variants in the same Caucasian schizophrenic sample and a Caucasian origin control cohort. The CYP2D6*2 allele was strongly associated with protection towards schizophrenia. The two observed associations may help to better understand the still unwell known physiopathological mechanisms implicated in schizophrenia aetiology and antipsychotic drug response

Made available in DSpace on 2014-07-29T15:30:42Z (GMT). No. of bitstreams: 1 dissertacao ana beatriz.pdf: 103876 bytes, checksum: dca149fa61a0329de409ef0e4cba735a (MD5) Previous issue date: 2007-10-11 / Introduction: the nasopharynx (NP) constitutes the primary ecological reservoir or source of dissemination of microorganisms as Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus and Gram-negative bacilli (GNB). Several studies demonstrated that asymptomatic nasopharyngeal (NP) carriage of pathogens is prevalent in young infants and precedes the development of invasive disease. Children in day-care centers act as an important vector for horizontal spread of the respiratory pathogens and GNB within the community. The infants are susceptible to condition of carrier and take a fundamental role in the epidemiology of respiratory infections. The nasopharyngeal flora becomes established during the first year of life and is densely colonized by a broad variety of microorganisms, commensal bacteria as well as potential pathogens that may cause infections. Epidemiologic studies demonstrate that many factors influence nasopharyngeal carriage rates: age, gender, season, acute respiratory illness, exposure to other children, socio-economic status, family size, warm-climate countries, passive smoking exposure, antibiotic therapy are risk factors of colonization of the NP by BGN. Objective: this study aimed to determinate the prevalence and susceptibility pattern of BGN isolated from NP of children less than five years old attending day-care centers at municipality of Goiânia. Methods: the investigation was conducted in the municipality of Goiânia as part of an ongoing prospective surveillance of Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus in children of 62 day-care centers. The surveillance was carried out from August to December, 2005 and was collected 1192 samples. The nasopharyngeal specimens were collected with a transwab, extrathin and flexible, placed in Stuart transport medium tubes and transported to the Laboratory of Bacteriology of the Federal University of Goias-Institute of Tropical Pathology and Public Health to processing. The isolates were identified by colony morphology, Gram staining technique and according to standardized tests. Susceptibility tests were performed by the disk diffusion method. Results: a total of 106 (8,9%) Gram-negative bacilli were isolated and 13 species were identified. The species more prevalent were twenty-six (24,5%) Enterobacter aerogenes, seventeen (16,0%) K. pneumoniae, eleven (10,4%) E. coli, eight (7,5%) E. agglomerans and five (4,7%) Pseudomonas sp. It was observed that forty-three (57,3%) GNB were resistant to ampicillin; twenty (26,7%) to trimethoprim-sulfametoxazole; eighteen (24,0%) showed resistance to amoxicillin-clavulanic acid and nine (12,0%) presented resistance to tetracycline. The production of extended-spectrum beta-lactamase was not detected. Conclusion: in this study was demonstrated that young children attending in daycare centers at municipality of Goiania might be GNB carrier and therefore have a fundamental role in the dissemination of microorganisms involved in community-acquired infections. It is necessary that more studies be developed to establish strategies more effectives to minimize the problem of the nasopharyngeal colonization and communityacquired infections due to importance and seriousness that both represent in the public health. / Introdução: a nasofaringe (NF) constitui o reservatório ecológico primário ou fonte de disseminação de microrganismos como Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus e bastonetes Gram-negativos (BGN). Vários estudos demonstraram que colonização nasofaríngea assintomática é prevalente em crianças e precede o desenvolvimento de doença invasiva. Crianças que freqüentam creches atuam como um importante vetor para disseminação horizontal de patógenos respiratórios e BGN dentro da comunidade. As crianças são suscetíveis à condição de portador e assumem um papel fundamental na epidemiologia de infecções respiratórias. A microbiota da nasofaringe é formada durante os primeiros anos de vida e é densamente colonizada por uma variedade de microrganismos, bactérias comensais assim como patógenos que podem causar infecções. Estudos epidemiológicos demonstram que muitos fatores influenciam o padrão de colonização da NF por BGN: idade, sexo, estação do ano, infecções respiratórias, contato com outras crianças, condição sócio-econômica, tamanho das famílias, países tropicais, exposição passiva a fumantes e antibioticoterapia. Objetivo: este estudo objetivou determinar a prevalência e padrão de suscetibilidade de BGN isolados da nasofaringe de crianças menores de 5 anos de idade que freqüentam creches no município de Goiânia. Métodos: a investigação é parte de um sistema de vigilância ativa, prospectiva e populacional de Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus em crianças de 62 creches. O estudo foi realizado no período de agosto a dezembro de 2005 e foram coletadas 1192 amostras. As coletas de espécimes da nasofaringe foram realizadas com um transwab, extrafino e flexível, inoculado no meio modificado para trasporte de Stuart e enviado ao Laboratório de Bacteriologia da Universidade Federal de Goiás-Instituto de Patologia Tropical e Saúde Pública para processamento. Os isolados foram identificados pela morfologia da colônia, coloração de Gram e testes bioquímicos padronizados. O peril de suscetibilidade foi determinado pelo método de disco difusão. Resultados: um total de 106 (8,9%) BGN foram isolados da nasofaringe de crianças e 13 espécies foram identificadas. As espécies mais freqüentes: foram vinte e seis (24,5%) Enterobacter aerogenes, dezessete (16,0%) K. pneumoniae, onze (10,4%) E. coli, oito (7.5%) E. agglomerans, cinco (4,7%) Pseudomonas sp. Observou-se que quarenta e três (57,3%) BGN apresentaram resistência a ampicilina; vinte (26,7%) foram resistentes a sulfametoxazol-trimetoprim; dezoito (24,0%) mostraram resistência a amoxacilina-ácido clavulânico e nove (12,0%) apresentaram resistência a tetraciclina. Conclusão: no presente estudo observou-se que crianças que freqüentam creches no município de Goiânia podem ser portadores de BGN e, portanto, assumem um papel fundamental na disseminação de microrganismos envolvidos em infecções comunitárias. É necessário que mais estudos sejam desenvolvidos para estabelecer estratégias mais eficazes para minimizar o problema da colonização nasofaríngea e de infecções adquiridas da comunidade devido à importância e seriedade que ambas representam no cenário da saúde pública.

Open Radio Access Networks (Open RANs) enable flexible cellular network deployments by adopting open-source software and white-box hardware to build reference architectures customizable to innovative target use cases. The Open Radio Access Network (O-RAN) Alliance defines specifications introducing new Radio Access Network (RAN) Intelligent Controller (RIC) functions that leverage open interfaces between disaggregated RAN elements to provide precise RAN control and monitoring capabilities using applications called xApps and rApps. Multiple xApps targeting novel use cases have been developed by the O-RAN Software Community (OSC) and incubated on the Near-Real-Time RIC (Near-RT RIC) platform. However, the Near-RT RIC has, so far, been demonstrated to support only a single xApp capable of controlling the RAN elements. This work studies the scalability of the OSC Near-RT RIC to support simultaneous control signaling by multiple xApps targeting the RAN element. We particularly analyze its internal message routing mechanism and experimentally expose the design limitations of the OSC Near-RT RIC in supporting simultaneous xApp control. To this end, we extend an existing open-source RAN slicing xApp and prototype a slice-aware User Equipment (UE) admission control xApp implementing the RAN Control E2 Service Model (E2SM) to demonstrate a multi-xApp control signaling use case and assess the control routing capability of the Near-RT RIC through an end-to-end O-RAN experiment using the OSC Near-RT RIC platform and an open-source Software Defined Radio (SDR) stack. We also propose and implement a tag-based message routing strategy for disambiguating multiple xApps to enable simultaneous xApp control. Our experimental results prove that our routing strategy ensures 100% delivery of control messages between multiple xApps and E2 Nodes while guaranteeing control scalability and xApp non-repudiation. Using the improved Near-RT RIC platform, we assess the security posture and resiliency of the OSC Near-RT RIC in the event of volumetric application layer Denial of Service (DoS) attacks exploiting the E2 interface and the E2 Application Protocol (E2AP). We design a DoS attack agent capable of orchestrating a signaling storm attack and a high-intensity resource exhaustion DoS attack on the Near-RT RIC platform components. Additionally, we develop a latency monitoring xApp solution to detect application layer signaling storm attacks. The experimental results indicate that signaling storm attacks targeting the E2 Terminator on the Near-RT RIC cause control loop violations over the E2 interface affecting service delivery and optimization for benign E2 Nodes. We also observe that a high-intensity E2 Setup DoS attack results in unbridled memory resource consumption leading to service interruption and application crash. Our results also show that the E2 interface at the Near-RT RIC is vulnerable to volumetric application layer DoS attacks, and robust monitoring, load-balancing, and DoS mitigation strategies must be incorporated to guarantee resiliency and high reliability of the Near-RT RIC. / Master of Science / Telecommunication networks need sophisticated controllers to support novel use cases and applications. Cellular base stations can be managed and optimized for better user experience through an intelligent radio controller called the Near-Real-Time Radio Access Network (RAN) Intelligent Controller (RIC) (Near-RT RIC), defined by the Open Radio Access Network (O-RAN) Alliance. This controller supports simultaneous connections to multiple base stations through the E2 interface and allows simple radio applications called xApps to control the behavior of those base stations. In this research work, we study the performance and behavior of the Near-RT RIC when a malicious or compromised base station tries to overwhelm the controller through a Denial of Service (DoS) attack. We develop a solution to determine the application layer communication delay between the controller and the base station to detect potential attacks trying to compromise the functionality and availability of the controller. To implement this solution, we also upgrade the controller to support multiple radio applications to interact and control one or more base stations simultaneously. Through the developed solution, we prove that the O-RAN Software Community (OSC) Near-RT RIC is highly vulnerable to DoS attacks from malicious base stations targeting the controller over the E2 interface.

<div> The Unmanned Aerial Vehicles (UAV) technology has evolved exponentially in recent years. Smaller and less expensive devices allow a world of new applications in different areas, but as this progress can be beneficial, the use of UAVs with malicious intentions also poses a threat. UAVs can carry weapons or explosives and access restricted zones passing undetected, representing a real threat for civilians and institutions. Acoustic detection in combination with machine learning models emerges as a viable solution since, despite its limitations related with environmental noise, it has provided promising results on classifying UAV sounds, it is adaptable to multiple environments, and especially, it can be a cost-effective solution, something much needed in the counter UAV market with high projections for the coming years. The problem addressed by this project is the need for a real-world adaptable solution which can show that an array of acoustic sensors can be implemented for the detection and localization of UAVs with minimal cost and competitive performance.<br><br></div><div> In this research, a low-cost acoustic detection system that can detect, in real time, about the presence and direction of arrival of a UAV approaching a target was engineered and validated. The model developed includes an array of acoustic sensors remotely connected to a central server, which uses the sound signals to estimate the direction of arrival of the UAV. This model works with a single microphone per node which calculates the position based on the acoustic intensity change produced by the UAV, reducing the implementation costs and being able to work asynchronously. The development of the project included collecting data from UAVs flying both indoors and outdoors, and a performance analysis under realistic conditions. <br><br></div><div> The results demonstrated that the solution provides real time UAV detection and localization information to protect a target from an attacking UAV, and that it can be applied in real world scenarios. </div><div><br></div>