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Sensor Position Optimization for Multiple LiDARs in Autonomous VehiclesKini, Rohit Ravindranath January 2020 (has links)
3D ranging sensor LiDAR, is an extensively used sensor in the autonomous vehicle industry, but LiDAR placement problem is not studied extensively. This thesis work proposes a framework in an open- source autonomous driving simulator (CARLA) that aims to solve LiDAR placement problem, based on the tasks that LiDAR is intended for in most of the autonomous vehicles. LiDAR placement problem is solved by improving point cloud density around the vehicle, and this is calculated by using LiDAR Occupancy Boards (LOB). Introducing LiDAR Occupancy as an objective function, the genetic algorithm is used to optimize this problem. This method can be extended for multiple LiDAR placement problem. Additionally, for multiple LiDAR placement problem, LiDAR scan registration algorithm (NDT) can also be used to find a better match for first or reference LiDAR. Multiple experiments are carried out in simulation with a different vehicle truck and car, different LiDAR sensors Velodyne 16 and 32 channel LiDAR, and, by varying Region Of Interest (ROI), for testing the scalability and technical robustness of the framework. Finally, this framework is validated by comparing the current and proposed LiDAR positions on the truck. / 3D- sensor LiDAR, är en sensor som används i stor utsträckning inom den autonoma fordonsindustrin, men LiDAR- placeringsproblemet studeras inte i stor utsträckning. Detta uppsatsarbete föreslår en ram i en öppen källkod för autonom körningssimulator (CARLA) som syftar till att lösa LiDAR- placeringsproblem, baserat på de uppgifter som LiDAR är avsedda för i de flesta av de autonoma fordonen. LiDAR- placeringsproblem löses genom att förbättra punktmolntätheten runt fordonet, och detta beräknas med LiDAR Occupancy Boards (LOB). Genom att introducera LiDAR Occupancy som en objektiv funktion används den genetiska algoritmen för att optimera detta problem. Denna metod kan utökas för flera LiDAR- placeringsproblem. Dessutom kan LiDAR- scanningsalgoritm (NDT) för flera LiDAR- placeringsproblem också användas för att hitta en bättre matchning för LiDAR för första eller referens. Flera experiment utförs i simulering med ett annat fordon lastbil och bil, olika LiDAR-sensorer Velodyne 16 och 32kanals LiDAR, och, genom att variera intresseområde (ROI), för att testa skalbarhet och teknisk robusthet i ramverket. Slutligen valideras detta ramverk genom att jämföra de nuvarande och föreslagna LiDAR- positionerna på lastbilen.
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Herstellung und Charakterisierung PHB basierter poröser Hohlstrukturen als NervenleitschienenHinüber, Claudia 30 August 2013 (has links)
Bei überkritisch großen Läsionen des peripheren Nervensystems, die zum Verlust von Motorik bzw. Sensibilität an Extremitäten führen und damit eine erhebliche Beeinträchtigung der Lebensqualität des Patienten bedingen, ist der Einsatz von Überbrückungsstrukturen bzw. Nervenleitkanälen notwendig. Da weder autologe Transplantate noch künstliche Konstrukte im klinischen Alltag bislang zufriedenstellende Ergebnisse lieferten, ist die Nachfrage nach alternativen Materialien und Konzepten des Tissue Engineering hoch.
Im Rahmen dieser Dissertation ist es gelungen zwei thermoplastische Methoden zu etablieren, mit denen aus dem im medizinischen Sinne interessanten und relativ neuartigen Material Poly(3-hydroxybuttersäure) in Kombination mit Polycaprolacton poröse resorbierbare Hohlstrukturen bzw. Hohlfasern erzeugt werden können, die den hohen aktuellen Anforderungen an eine Nervenleitschiene gerecht werden. Neben der Entwicklung und Charakterisierung sowie Modifizierung der erzeugten Leitkanäle bezüglich Porosität, Permeationsverhalten, mechanische Eigenschaften und Oberflächenfunktionalisierung, konnten strukturelle als auch biochemische Reize in diese integriert werden, die in einer Reihe von ex-vivo Studien mit neuronalen Primärzellen hinsichtlich Adhäsion, Vitalität und Ausbreitungsverhalten untersucht werden konnten.
Es konnte eine Art „Toolbox“ aus PHB basierten Strukturen erstellt werden, die es erlaubt hierarchische Strukturen zusammenzustellen, die entsprechend des peripheren Defektes zusammengesetzt und biomolekular maßgeschneidert werden könnten, um die native Struktur bestmöglich temporär bis zur vollständigen Regeneration zu imitieren und damit die Therapie größerer Defekte zu ermöglichen bzw. die als Plattform für weitere Konzepte der Grundlagenforschung im Bereich des Neuro-Tissue Engineering dienen.
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Separation of Transition and Heavy Metals Using Stationary Phase Gradients and Chelation Thin Layer Chromatography / Evaluation of the Effectiveness of POGIL-PCL WorkshopsStegall, Stacy L 01 January 2017 (has links)
Gradient surfaces exhibit a variation in functionality along the length of the surface. One method for preparing gradients is controlled-rate infusion (CRI). In Part 1 of this work, CRI was used to prepare gradients for the purpose of separating transition and heavy metals. Initial work on this project was focused on controlling the retention of the metal ions by varying the number of amine groups, aminoalkoxysilane concentration, and the infusion time. The retention factors of four metal ions varied predictably with increasing number of amine groups, increasing aminoalkoxysilane concentration, and increasing infusion time, producing small but useful changes in the retention factors. The continuation of this project involved the preparation of two-dimensional multi-component gradients on TLC plates, which were used to separate six transition and heavy metals. The retention, and thus the separation, was affected by the presence or absence of a gradient and the direction of the gradient.
Part 2 of this work focused on understanding the factors that motivated instructors in the early and late stages in the process of change. Instructors who attended the POGIL-PCL (Process-Oriented Guided Inquiry Learning in the Physical Chemistry Laboratory) workshops were asked to complete online surveys. The goals of the first survey were to understand the factors that initially interested instructors in POGIL-PCL, to determine if instructors enter the implementation stage, and to understand the factors that affect how instructors implement POGIL-PCL. Later surveys were designed to explore the development of the POGIL-PCL network and assess whether implementation is sustained over time.
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Assessment of Psychopathy in Incarcerated FemalesJackson, Rebecca L. 08 1900 (has links)
Psychopaths constitute only an estimated 1% of the population, yet they are responsible for a disproportionately large number of violent and nonviolent crimes. The literature addressing this syndrome among male offenders is quite extensive. In contrast, psychopathy and its underlying factor structure remains understudied among female offenders. Research has suggested marked gender differences in the prevalence, clinical characteristics, and underlying dimensions of psychopathy. This study examined the dimensions of psychopathy in a female offender sample. The Psychopathy Checklist-Revised and the Self Report Psychopathy-II (SRP-II) were administered to 119 female inmates at Tarrant County Jail in Fort Worth, TX. Confirmatory factor analyses of the Psychopathy Checklist-Revised (PCL-R) did not support the use of the traditional two factor male model or a recently proposed two- factor female model. This thesis also addressed females' self-appraisal of PCL-R Factor 1 characteristics as well as the usefulness of the self-administered Self-Report Psychopathy-II as a screen for psychopathy.
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Examining PTSD Symptoms and the Effectiveness of Group Therapy Among African American and Caucasian VeteransColeman, Jennifer A 01 January 2016 (has links)
Millions of Americans have served in the military, and improved survival rates in wars have increased the percentage of those who return home. Posttraumatic stress disorder (PTSD) is one of the most prevalent mental health diagnoses for veterans. Although few studies have examined the link, previous research as well as the minority stress model and transgenerational trauma theories, suggest that race may be associated with PTSD, particularly in military samples. The current study examined whether there were differences in PTSD symptomology (global and symptom cluster-specific) based on veterans’ race and whether group therapy effectively reduced symptoms of PTSD. Data were collected from male veterans who identified as non-Hispanic Caucasian or non-Hispanic African American (N = 450) and participated in a 10-week, combat-related, group therapy PTSD Recovery Program between 2010 and 2014. Participants completed the Posttraumatic Stress Disorder Checklist- Military version (PCL-M) measure at three time points (intake, pre-treatment, and post-treatment). Global PTSD symptoms and three of the four symptom clusters did not differ between African American and Caucasian participants at intake. However, the symptom cluster of re-experiencing was higher for African Americans compared to Caucasians at intake. Additionally, the Recovery Program led to a reduction in PCL-M scores. This symptom reduction occurred regardless of race, with neither racial group improving more than the other. Moreover, dropout rates for the Recovery Program were on par or better than those for other trauma-focused therapies. Although the overall racial and ethnic composition of groups was not related to most outcomes, the percentage of racial/ethnic minority members in groups was negatively associated with the number of sessions attended for Caucasians. Findings also indicated that the PCL-M demonstrated good psychometric properties in an African American sample. One implication from this study is that the current conceptualization and measurement of PTSD may be insufficient. It may be more helpful to examine specific PTSD symptom clusters, especially when assessing differences by race. The effectiveness of the PTSD Recovery Program supports alternative options to treating veterans with PTSD in the VA system. Last, it is important for therapists to consider the composition of groups when conducting group therapy.
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Prepara??o de filmes polim?ricos biodegrad?veis para a aplica??o em embalagens para cosm?ticosDias, Lucas Weber 29 August 2017 (has links)
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Previous issue date: 2017-08-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The main function of the packaging is to protect the cosmetic from the external environment, avoiding undesirable changes in the product that is contained inside, and thus indispensable for its storage and transpotation. However, its disposal improperly generates a large volume of solid waste, which is directly related to the environmental impact. One of the alternatives to minimize this impact is the use of packages made from biodegradable polymeric films based on polyacrylic acid (PLA), poly (lactic acid ? co- glycolic acid) (PLGA) and polycaprolactone (PCL), blends of theses polymers and incorporation of Zeolites 13x. The thermal, mechanical optical, water vapor barrier and degradation time in saline solution of polymeric systems are evaluated for application as cosmetic packaging. The technique used for the preparation of the polymer films was that of Solvent Casting. The polymer films were characterized by the techniques of UV-Vis Spectrophotometry, Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Scsannig Electron Microscopy (SEM), transparency, water vapor permeability, mechanical assay and absorption spectroscopy atomic. The transmittance results showed that the PCL and PLA blends showed greater blockage to the passage of radiation (190 - 1100nm) and water vapor permeability. The incorporation of PLA or PLGA to the pure PCL resulted in material with batter thermal properties, but more rigid and brittle, not modifying the degradation process until 120 days of incubation. The incorporation of 15% Zeolite 13x into the PCL/PLA blends did not significantly modify the properties evaluated. / As embalagens t?m como principal fun??o, proteger o cosm?tico do meio externo, evitando que ocorram altera??es indesej?veis no produto que est? contido no seu interior, sendo assim indispens?vel para o seu armazenamento e transporte. Por?m, o seu descarte de forma inadequada gera um grande volume de res?duos s?lidos, que est? diretamente relacionado com o impacto ambiental. Uma das alternativas para minimizar este impacto ? a utiliza??o de embalagens confeccionadas a partir de pol?meros biodegrad?veis. Desta maneira, o presente trabalho tem como objetivo a prepara??o e caracteriza??o de filmes polim?ricos biodegrad?veis baseados em Poli ? ?cido l?ctico (PLA), Poli (?cido l?ctico ? co- ?cido glic?lico) (PLGA) e Policaprolactona (PCL), blendas destes pol?meros e incorpora??o de Ze?litas 13x. S?o avaliadas as propriedades t?rmicas, mec?nicas, ?pticas, de barreira a vapor de ?gua e o tempo de degrada??o em solu??o salina dos sistemas polim?ricos, visando aplica??o como embalagem para cosm?ticos. A t?cnica utilizada para a prepara??o dos filmes polim?ricos foi a de Solvent Casting. Os filmes polim?ricos foram caracterizados pelas t?cnicas de Espectrofotometria UV-Vis, Calorimetria Explorat?ria Diferencial (DSC), An?lise Termogravim?trica (TGA), Microscopia Eletr?nica de Varredura (MEV-FEG), transpar?ncia, permeabilidade a vapor de ?gua, ensaio mec?nico e Espectroscopia de absor??o at?mica. Os resultados de transmit?ncia mostraram que a blenda de PCL e PLA apresentou maior bloqueio ? passagem de radia??o (190 nm ? 1100 nm) e ? permeabilidade de vapor de ?gua. A incorpora??o de PLA ou PLGA ao PCL puro resultou num material com melhores propriedades t?rmicas, por?m mais r?gido e quebradi?o, n?o modificando o processo de degrada??o at? 120 dias de incuba??o. A incorpora??o de 15% Ze?lita 13x ? blenda de PCL/PLA n?o modificou significativamente as propriedades avaliadas.
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An Investigation of Security in Near Field Communication SystemsOlivieri, Steven 26 January 2015 (has links)
Increasingly, goods and services are purchased over the Internet without any form of physical currency. This practice, often called e-commerce, offers sellers and buyers a convenient way to trade globally as no physical currency must change hands and buyers from anywhere in the world can browse online store fronts from around the globe. Nevertheless, many transactions still require a physical presence. For these sorts of transactions, a new technology called Near Field Communication has emerged to provide buyers with some of the conveniences of e-commerce while still allowing them to purchase goods locally. Near Field Communication (NFC), an evolution of Radio-Frequency Identification (RFID), allows one electronic device to transmit short messages to another nearby device. A buyer can store his or her payment information on a tag and a cashier can retrieve that information with an appropriate reader. Advanced devices can store payment information for multiple credit and debit cards as well as gift cards and other credentials. By consolidating all of these payment forms into a single device, the buyer has fewer objects to carry with her. Further, proper implementation of such a device can offer increased security over plastic cards in the form of advanced encryption. Using a testing platform consisting of commercial, off-the-shelf components, this dissertation investigates the security of the NFC physical-layer protocols as well as the primary NFC security protocol, NFC-SEC. In addition, it analyzes a situation in which the NFC protocols appear to break, potentially compromising sensitive data. Finally, this dissertation provides a proof of security for the NFC-SEC-1 variation of NFC-SEC.
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Modificação química do poli(3-hidroxibutirato) e preparação de membranas por eletrofiação para aplicação em biomateriais. / Poly(3-hydroxybutyrate) chemical modification and fiber mats preparation by electrospinning for biomedical applications.Katia Yabunaka Sakaguti 08 November 2018 (has links)
Devido ao crescente interesse em polímeros biodegradáveis, muitos estudos têm sido realizados a fim de se obter polímeros biodegradáveis com melhores propriedades mecânicas e de processamento. O poli(3-hidroxibutirato) (PHB) tem sido apresentado como um substituto para polímeros não-biodegradáveis em aplicações comerciais. Porém, sua elevada cristalinidade, instabilidade térmica e alto custo de produção são problemas que dificultam sua comercialização. Uma alternativa para modificá-lo e melhorar suas propriedades mecânicas é através de reações de transesterificação com poli(?-caprolactona) (PCL), um poliéster sintético, também biodegradável e com alto potencial para uso como biomaterial. Neste trabalho, realizou-se a extrusão reativa de blendas de PHB e PCL e o copolímero obtido foi caracterizado por ensaios de solubilidade, calorimetria exploratória diferencial (DSC), espectroscopia no infravermelho por transformada de Fourier (FTIR), espectrometria de ressonância magnética nuclear de hidrogênio (RNM-1H) e de carbono (RNM-13C). Os resultados indicaram que houve modificação do PHB resultando no copolímero PHB-co-PCL, que apresentou menor cristalinidade que os homopolímeros de partida. Com o PHB-co-PCL, foram feitas medidas de viscosidade e ensaios de eletrofiação, variando-se os parâmetros do processo e da solução. As análises por microscopia eletrônica de varredura (MEV) apontaram formação de fibras lisas e uniformes com diâmetros médios entre 900 a 1200 nm. Análise de viabilidade celular confirmou que o material não é citotóxico, favorecendo sua aplicabilidade em mantas porosas na engenharia de tecidos. / Due to the increasing interest in biodegradable polymers, many studies have been conducted in order to obtain biodegradable polymers with improved mechanical and processing properties. The poly(3-hydroxybutyrate) (PHB) has been proposed as an ideal substitute for non-biodegradable polymers in commercial applications. However, its high crystallinity, thermal instability and high production costs are problems that have limited its commercialization. An alternative to modify it and improve its mechanical properties is through transesterification reactions with poly(?-caprolactone) (PCL), a synthetic polyester, also biodegradable and with high potential for use as a biomaterial. In this work, reactive extrusion of PHB/PCL blend was carried out, and the copolymer was characterized by solubility tests, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), hydrogen (1H-NMR) and carbon (13C-NMR) nuclear magnetic resonance spectroscopies. The results indicated that PHB was modified, resulting in the copolymer PHB-co-PCL, showing lower crystallinity than the homopolymers. Viscosity measurements of PHB-co-PCL solutions were performed and electrospinning tests were carried out under different conditions. The scanning electron microscopy analysis (SEM) indicated the formation of smooth and uniform fibers, with average diameter between 900-1200 nm. Cell viability analysis confirmed that the material is not cytotoxic, favoring its applicability for the production of porous fiber mats in tissue engineering.
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Modificação química do poli(3-hidroxibutirato) e preparação de membranas por eletrofiação para aplicação em biomateriais. / Poly(3-hydroxybutyrate) chemical modification and fiber mats preparation by electrospinning for biomedical applications.Sakaguti, Katia Yabunaka 08 November 2018 (has links)
Devido ao crescente interesse em polímeros biodegradáveis, muitos estudos têm sido realizados a fim de se obter polímeros biodegradáveis com melhores propriedades mecânicas e de processamento. O poli(3-hidroxibutirato) (PHB) tem sido apresentado como um substituto para polímeros não-biodegradáveis em aplicações comerciais. Porém, sua elevada cristalinidade, instabilidade térmica e alto custo de produção são problemas que dificultam sua comercialização. Uma alternativa para modificá-lo e melhorar suas propriedades mecânicas é através de reações de transesterificação com poli(?-caprolactona) (PCL), um poliéster sintético, também biodegradável e com alto potencial para uso como biomaterial. Neste trabalho, realizou-se a extrusão reativa de blendas de PHB e PCL e o copolímero obtido foi caracterizado por ensaios de solubilidade, calorimetria exploratória diferencial (DSC), espectroscopia no infravermelho por transformada de Fourier (FTIR), espectrometria de ressonância magnética nuclear de hidrogênio (RNM-1H) e de carbono (RNM-13C). Os resultados indicaram que houve modificação do PHB resultando no copolímero PHB-co-PCL, que apresentou menor cristalinidade que os homopolímeros de partida. Com o PHB-co-PCL, foram feitas medidas de viscosidade e ensaios de eletrofiação, variando-se os parâmetros do processo e da solução. As análises por microscopia eletrônica de varredura (MEV) apontaram formação de fibras lisas e uniformes com diâmetros médios entre 900 a 1200 nm. Análise de viabilidade celular confirmou que o material não é citotóxico, favorecendo sua aplicabilidade em mantas porosas na engenharia de tecidos. / Due to the increasing interest in biodegradable polymers, many studies have been conducted in order to obtain biodegradable polymers with improved mechanical and processing properties. The poly(3-hydroxybutyrate) (PHB) has been proposed as an ideal substitute for non-biodegradable polymers in commercial applications. However, its high crystallinity, thermal instability and high production costs are problems that have limited its commercialization. An alternative to modify it and improve its mechanical properties is through transesterification reactions with poly(?-caprolactone) (PCL), a synthetic polyester, also biodegradable and with high potential for use as a biomaterial. In this work, reactive extrusion of PHB/PCL blend was carried out, and the copolymer was characterized by solubility tests, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), hydrogen (1H-NMR) and carbon (13C-NMR) nuclear magnetic resonance spectroscopies. The results indicated that PHB was modified, resulting in the copolymer PHB-co-PCL, showing lower crystallinity than the homopolymers. Viscosity measurements of PHB-co-PCL solutions were performed and electrospinning tests were carried out under different conditions. The scanning electron microscopy analysis (SEM) indicated the formation of smooth and uniform fibers, with average diameter between 900-1200 nm. Cell viability analysis confirmed that the material is not cytotoxic, favoring its applicability for the production of porous fiber mats in tissue engineering.
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Validez del modelo de las cuatro facetas de la psicopatía de R. D. Hare (2003) en una muestra penitenciaria: evidencia desde el laboratorio psicofisiológico.Tormo Irún, Maria Pilar 24 January 2008 (has links)
El objetivo general era estudiar el patrón de relaciones de la psicopatía, entendida como un constructo jerárquico subdividido en dos factores y cuatro facetas (interpersonal, afectiva, estilo impulsivo/irresponsable y antisocial), con variables sociodemográficas, psicológicas, criminológicas y diversos indicadores de la experiencia emocional, utilizando el paradigma de la visión de imágenes. El estudio se realizó en un centro penitenciario con 75 internos penados, evaluados mediante el Psychopathy Checklist-Revised (PCL-R) de R. D. Hare (2003). Las medidas registradas en un contexto de laboratorio incluían indicadores de: a) la experiencia emocional ante distintos estímulos afectivos, evaluada directa (estimaciones en valencia afectiva, arousal y dominancia) e indirectamente (tiempo de reacción de discriminación afectiva); b) la reactividad fisiológica ante esos estímulos, a nivel autonómico (conductancia de la piel y tasa cardíaca) y somático (actividad electromiográfica de los músculos faciales corrugador, cigomático y orbicular del ojo); y c) la reactividad defensiva, mediante la modulación del reflejo de sobresalto. En conjunto, los resultados obtenidos respaldan empíricamente la utilidad del modelo de las cuatro facetas de la psicopatía de Hare en población penitenciaria y, en particular, la asociación exclusiva de las características afectivas del síndrome (crueldad, ausencia de empatía.) con una anomalía emocional de carácter básico y, quizá derivado de lo anterior, con un patrón de comportamiento antisocial y violento.
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