Tesis:

1

Leroy, Anaïs. "Ιmplicatiοn du RΝΜDA endοthélial dans l'angiοgenèse rétinienne en cοnditiοns physiοlοgiques et dans un cοntexte d'alcοοlisatiοn fοetale". Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMR124.

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Le syndrome d’alcoolisation fœtale (SAF) est la principale cause de retard mental et représente la forme la plus sévère des troubles causés par l’alcoolisation fœtale (TCAF). Il se caractérise par divers troubles du neurodéveloppement, et son diagnostic repose sur un retard de croissance anté- et/ou postnatal, des anomalies du système nerveux central (SNC), et une dysmorphie crânio-faciale présente dès la naissance. Toutefois, la majorité des enfants exposés in utero à l’alcool ne présentent pas ces dysmorphies caractéristiques, bien qu’ils développent progressivement des troubles du neurodéveloppement. Cela entraîne des errances diagnostiques pour nombre d’enfants TCAF. Un diagnostic précoce permettrait une prise en charge rapide et adaptée, à un moment où la plasticité cérébrale est importante.Des travaux antérieurs de notre laboratoire ont montré qu’une exposition in utero à l’alcool entraîne des atteintes de l’angiogenèse et de la migration cellulaire corticale, tant chez l’humain que dans un modèle murin reproduisant un phénotype TCAF. Par ailleurs, la littérature met en évidence des atteintes oculaires, notamment une vascularisation rétinienne altérée chez les individus atteints de SAF. Étant donné que la rétine est une extension du SNC, nous avons émis l’hypothèse que les anomalies neurovasculaires cérébrales observées pourraient également être présentes au niveau de la rétine. Une première partie de mes travaux de thèse a consisté à caractériser les atteintes neurovasculaires de la rétine dans un modèle d’exposition prénatale à l’alcool (EPA). Les résultats ont mis en évidence un retard de développement du réseau vasculaire et une perturbation de l’organisation des cellules neuronales rétiniennes, notamment des cellules ganglionnaires et des interneurones immatures associés aux vaisseaux perforants.Les mécanismes moléculaires des effets de l’alcool sur le neurodéveloppement restent complexes et mal compris en raison des nombreuses cibles de l’éthanol. Parmi elles, le récepteur NMDA (RNMDA) est particulièrement affecté en présence d’alcool et joue un rôle dans la tolérance, la dépendance et le sevrage. Ce récepteur, exprimé par les cellules endothéliales néonatales, participe également aux processus angiogéniques. La deuxième partie de ma thèse a donc consisté à étudier l’implication du RNMDA endothélial dans le développement neurovasculaire de la rétine, en conditions physiologiques et après EPA. Un modèle murin invalidé pour le RNMDA au niveau endothélial a été utilisé. Les résultats montrent un retard dans le développement du réseau vasculaire rétinien et une altération du nombre des cellules neuronales dans la rétine des souris invalidées. L’association des cellules amacrines avec les vaisseaux perforants est également perturbée. En condition physiopathologique, l’invalidation du RNMDA endothélial atténue, en partie, les effets de l’EPA sur le développement de la rétine, soulignant l’implication de ce récepteur dans les atteintes neurovasculaires induites par l’alcool.Étant donné que l’œil constitue une fenêtre vers le cerveau, il représente un outil de diagnostic prometteur dans diverses pathologies. Des analyses d’imagerie rétinienne in vivo, via le fond d’œil, la tomographie par cohérence optique (OCT), et l’électrorétinogramme, ont été mises en place pour déterminer si les anomalies neurovasculaires induites par une EPA pouvaient être détectées précocement par ces approches. Les résultats préliminaires suggèrent l’existence d’atteintes du réseau vasculaire et de la couche des cellules ganglionnaires, détectables par l’analyse du fond d’œil et d’OCT chez des animaux exposés à l’alcool in utero. L’ensemble de ces travaux indique que l’analyse des atteintes neurovasculaires de la rétine pourrait, à l’avenir, soutenir le diagnostic précoce des enfants TCAF. Une transposition de ces approches chez l’Homme dans un contexte d’alcoolisation fœtale est désormais nécessaire
Fetal Alcohol Syndrome (FAS) is the leading cause of intellectual disability and represents the most severe form of Fetal Alcohol Spectrum Disorders (FASD). It is characterized by various neurodevelopmental impairments, and its diagnosis relies on pre- and/or postnatal growth retardation, central nervous system (CNS) anomalies, and craniofacial dysmorphia present at birth. However, most children exposed to alcohol in utero do not display these characteristic dysmorphias, though they progressively develop neurodevelopmental disorders. This results in diagnostic delays for many FASD-affected children. Early diagnosis would enable prompt and appropriate intervention, especially when brain plasticity is high.Previous work from our laboratory has shown that in utero exposure to alcohol impairs angiogenesis and cortical cell migration, both in humans and in a murine model reproducing an FASD phenotype. Additionally, the literature highlights ocular impairments, including altered retinal vascularization in individuals affected by FAS. Since the retina is an extension of the CNS, we hypothesized that the neurovascular anomalies observed in the brain might also be present in the retina. The first part of my doctoral work focused on characterizing neurovascular impairments in the retina in a model of prenatal alcohol exposure (PAE). The findings revealed delayed development of the vascular network and disrupted organization of retinal neuronal cells, particularly ganglion cells and immature interneurons associated with penetrating vessels.The molecular mechanisms of alcohol’s effects on neurodevelopment remain complex and poorly understood due to the numerous targets of ethanol. Among these, the NMDA receptor (NMDAR) is particularly affected by alcohol and plays a role in tolerance, dependence, and withdrawal. This receptor, expressed by neonatal endothelial cells, also participates in angiogenic processes. The second part of my thesis focused on studying the involvement of endothelial NMDAR in retinal neurovascular development under both physiological conditions and after PAE. A murine model with endothelial-specific NMDAR deletion was used. The results demonstrate a delay in the development of the retinal vascular network and an alteration in the number of neuronal cells in the retinas of the NMDAR-deficient mice. The association of amacrine cells with penetrating vessels was also disrupted. Under pathological conditions, endothelial NMDAR deletion partially attenuated the effects of PAE on retinal development, highlighting the involvement of this receptor in alcohol-induced neurovascular impairments.Since the eye provides a window into the brain, it represents a promising diagnostic tool for various pathologies. In vivo retinal imaging analyses, using fundus photography, optical coherence tomography (OCT), and electroretinography, were implemented to determine if neurovascular anomalies induced by PAE could be detected early by these methods. Preliminary results suggest that impairments in the vascular network and ganglion cell layer can be detected through fundus and OCT analysis in animals exposed to alcohol in utero. Collectively, this research indicates that retinal neurovascular impairment analysis could, in the future, support the early diagnosis of FASD-affected children. Transposing these approaches to humans in the context of fetal alcohol exposure is now necessary

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2

Sautreuil, Camille. "Etude du CD146 placentaire comme biomarqueur de troubles de l'angiogenèse cérébrale suite à une alcoolisation in utero. Alcoolisation foetale : le placenta au secours du diagnostic précoce des troubles du développement cérébral de l'enfant Impaired expression of the angiogenic placental factor CD146 by in utero alcohol exposure alters the fetal brain vasculature". Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR149.

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Le Syndrome d’Alcoolisation Foetale (SAF) est l’atteinte la plus sévère des Troubles Causés par l’Alcoolisation Foetale (TCAF). Il se traduit, chez l’enfant, par une triade de manifestations cliniques (dysmorphies craniofaciales, retard de croissance pré et postnatal, troubles neurologiques et comportementaux). Toutefois, en raison de l’absence d’anomalies morphologiques évidentes, la plupart des enfants TCAF échappent à un diagnostic précoce. Pour autant, ces enfants ne sont pas dépourvus d’atteintes cérébrales et les conséquences neurodéveloppementales et comportementales se révèleront progressivement avec l’âge. Le défi, pour les cliniciens, consiste donc à diagnostiquer au plus tôt ces enfants TCAF afin de mettre en place un accompagnement adapté à une période (0-5 ans) où le potentiel de récupération est important. A ce jour, même s’il existe des biomarqueurs d’exposition à l’alcool, ces derniers ne permettent pas de déterminer s’il y a eu une atteinte cérébrale. De récents travaux menés au Laboratoire ont mis en évidence l’existence d’un lien fonctionnel « Placenta-Cerveau » impliqué dans le contrôle de l’angiogenèse corticale du foetus. Ainsi, le PlGF a été identifié comme un premier biomarqueur placentaire d’atteinte cérébrale et une procédure de valorisation a été engagée. Mon projet de thèse a consisté à rechercher si un autre facteur pro-angiogénique placentaire associé au signalosome du PlGF/VEGF, le CD146, pouvait également constituer un acteur de la dysfonction Placenta-Cerveau suite à l’exposition in utero à l’alcool. De plus, une approche sans a priori par analyse transcriptomique inter-organes a également été initiée pour tenter d’élargir la signature « angiogénique » des effets délétères de l’alcool sur la communication entre ces deux organes. Concernant l’étude sur le CD146, les données obtenues sur des extraits de villosités de placenta humain montrent que le profil d’expression des ARNm codant le CD146 ne varie pas à différents stades gestationnels. En revanche, l’étude du profil protéique par la technique de Western blot indique une augmentation marquée de l’expression de la forme membranaire du CD146 avec le terme, et la forme soluble du CD146 est clairement détectée. Chez la Souris, les profils d’expression ARNm et protéique au niveau placentaire sont comparables à ceux caractérisés chez l’humain. L’immunohistochimie indique que l’expression du CD146 est endothéliale. De plus, les résultats obtenus par une approche ELISA indiquent que le sCD146 est détecté dans le sang céphalique foetal. Dans le cerveau, le CD146 est beaucoup moins exprimé que dans le placenta, et la forme membranaire est majoritaire. L’alcoolisation in utero perturbe les expressions placentaire et cérébrale de la forme soluble de CD146 en la diminuant fortement dans le placenta et en l’augmentant dans le cerveau foetal. De plus, certains éléments du signalosome du CD146 ont une expression qui est inversement altérée entre le placenta et le cerveau. Enfin, la répression placentaire du CD146 par l’électroporation de CRISPR-Cas9 entraîne une désorganisation du réseau microvasculaire cortical comparable à celle observée suite à une exposition in utero à l’alcool. En complément de l’étude ciblée sur le CD146, une étude sans a priori a été menée par analyse transcriptomique. Les résultats indiquent que l’alcoolisation in utero affecte peu, quantitativement, la signature transcriptomique « Placenta-Cerveau ». Toutefois, l’alcoolisation se traduit par l’émergence de populations géniques qui sont soit spécifiquement présentes dans le groupe « Contrôle » ou dans le groupe « Alcool ». Une analyse qualitative GO orientée « Angiogenèse » a permis d’identifier une liste de gènes dont le profil d’expression « Placenta-Cerveau » est significativement impactée par l’alcool. Une étape de validation de certains de ces gènes va être engagée
Fetal Alcohol Syndrome (FAS) refers to the most severe expression of Fetal Alcohol Spectrum Disorder (FASD). It associates several clinical defects such as craniofacial dysmorphism, growth retardation and neurological/behavioral disabilities. However, due to the absence of obvious dysmorphic features, most children with FASD are late or misdiagnosed. Nevertheless, these infants are not devoid of neurodevelopmental impairments and neurobehavioral troubles that will progressively appear with age. Consequently, the challenge for clinicians consists in the early diagnosis of FASD to avoid the loss of precious years of care. Even if several biomarkers of alcohol exposure have been characterized, there are currently no biomarkers of brain defects. Recent data from the Laboratory have shown a functional link “Placenta-Brain” involved in the control of the fetal cortical angiogenesis. Thus, PlGF has been identified as a first placental biomarker of brain impairments, and a valorization process has been initiated. My thesis project consisted to research if another placental proangiogenic factor associated to the VEGF/PlGF signalosome could also be an actor of the Placenta-Brain dysfunction induced by in utero alcohol exposure. Moreover, a non-oriented trans-organ transcriptomic approach has also been initiated trying to broaden the “angiogenic” signature of the alcohol-induced deleterious effects on the placenta-brain axis. About the CD146 study, data obtained on villous extracts from human placentas showed that the expression profile of mRNA didn’t changed between gestational weeks. However, Western blot analyses showed a marked increase of the expression of the membrane form (mCD146) with term and the soluble form sCD146 was clearly detected. In mouse, the mRNA and protein expression profiles in the placenta were very similar to those characterized in human. Immunohistochemistry indicated that the CD146 expression is at least endothelial. Moreover, results obtained by ELISA indicated that the sCD146 is detected in the fetal cephalic blood. In the mouse brain, the expression of CD146 was much less expressed than in the placenta and mCD146 is the main form. In utero alcohol exposure disrupted the expression of sCD146 decreasing in the placenta and increasing in the fetal brain. Additionally, several members of the CD146 signalosome were inversely impacted by alcohol between the placenta and the fetal brain. Finally, the placental repression of CD146 by in utero electroporation of CD146 CRISPR-Cas9 plasmids resulted in a disorganization of the microvascular cortical network, similar to the one observed after an in utero alcohol exposure. In addition to the first study focused on CD146, a non-oriented transcriptomic approach was undertaken to investigate the effects of alcohol on the placenta-brain interactions. Results indicated that in utero alcohol exposure have quantitatively a little impact on the “Placenta-Brain” transcriptomic signature. Nevertheless, alcohol exposure induced specific dysregulations of genes representative of the placenta/brain axis and a qualitative GO analysis using the “angiogenesis” filter allowed us to identify a list of genes significantly impaired. A validation step is now planned. To conclude, the targeted approach done on CD146 supports the existence of a functional placenta-fetal brain interaction and involved in the control of angiogenesis. The CD146 could constitute another placental biomarker of brain development defects induced by in utero alcohol exposure. Moreover, the transcriptomic approach has provided promising data regarding angiogenesis dysfunction and neurodevelopmental troubles and it would contribute to the characterization of a transcriptomic signature for the early diagnosis of FASD

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3

Kumar, Anuj. "Increasing TLB reach using TCAM cells". Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1341.

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We propose dynamic aggregation of virtual tags in TLB to increase its coverage and improve the overall miss ratio during address translation. Dynamic aggregation exploits both the spatial and temporal locality inherent in most application programs. To support dynamic aggregation, we introduce the use of ternary-CAM (TCAM) cells at the second-level TLB. The modified TLB architecture results in an increase of TLB reach without additional CAM entries. We also adopt bulk prefetching concurrently with aggregation technique to enhance the benefits due to spatial locality. The performance of the proposed TLB architecture is evaluated using SPEC2000 benchmarks concentrating on those that show high data TLB miss ratios. Simulation results indicate a reduction in miss ratios between 59% and 99.99% for all the considered bench-marks except for one benchmark, which has a reduction of 10%. We show that the L2 TLB when enhanced using TCAM cells is an attractive solution to high miss ratios exhibited by applications.

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4

Surprise, Jason Mathew. "An energy efficient TCAM enhanced cache architecture". Texas A&M University, 2005. http://hdl.handle.net/1969.1/2314.

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Microprocessors are used in a variety of systems ranging from high-performance super computers running scientific applications to battery powered cell phones performing realtime tasks. Due to the large disparity between processor clock speed and main memory access time, most modern processors include several caches, which consume more than half of the total chip area and power budget. As the performance gap between processors and memory has increased, the trend has been to increase the size of the on-chip caches. However, increasing the cache size also increases its access time and energy consumptions. This growing power dissipation problem is making traditional cooling and packaging techniques less effective thus requiring cache designers to focus more on architectural level energy efficiency than performance alone. The goal of this thesis is to propose a new cache architecture and to evaluate its efficiency in terms of miss rate, system performance, energy consumption, and area overhead. The proposed architecture employs the use of a few Ternary-CAM (TCAM) cells in the tag array to enable dynamic compression of tag entries containing contiguous values. By dynamically compressing tag entries, the number of entries in the tag array can be reduced by 2N, where N is the number of tag bits that can be compressed. The architecture described in this thesis is applicable to any cache structure that uses Content Addressable Memory (CAM) cells to store tag bits. To evaluate the effectiveness of the TCAM Enhanced Cache Architecture for a wide scope of applications, two case studies were performed ?? the L2 Data-TLB (DTLB) of a high-performance processor and the L1 instruction and data caches of a low-power embedded processor. Results indicate that a L2 DTLB implementing 3-bit tag compression can achieve 93% of the performance of a conventional L2 DTLB of the same size while reducing the on-chip energy consumption by 74% and the total area by 50%. Similarly, an embedded processor cache implementing 2-bit tag compression achieves 99% of the performance of a conventional cache while reducing the on-chip energy consumption by 33% and the total area by 10%.

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5

Al-S'adi, Mahmoud. "TCAD based SiGe HBT advanced architecture exploration". Thesis, Bordeaux 1, 2011. http://www.theses.fr/2011BOR14239/document.

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Dans le but d’améliorer les transistors bipolaires TBH SiGe, nous proposons d’étudier l’impact de la contrainte mécanique sur leurs performances. En effet, cette contrainte permet de libérer un degré de liberté supplémentaire pour améliorer les propriétés du transport grâce à un changement de la structure de bande d’énergie du semiconducteur. Ainsi, nous avons proposé de nouvelles architectures de composants basées sur l’ingénierie de la contrainte mécanique dans les semiconducteurs. Deux approches ont été utilisées dans cette étude pour générer la tension mécanique adéquate à l'intérieur du dispositif. La première approche consiste à appliquer une contrainte mécanique sur la base du transistor en utilisant une couche de SiGe extrinsèque. La seconde approche vise à appliquer une contrainte dans la région du collecteur en utilisant une couche contrainte. Les résultats obtenus montrent que cette méthode peut être une approche prometteuse pour améliorer les performances des TBH
The Impact of strain engineering technology applied on Si BJT/SiGe HBT devices on the electrical properties and frequency response has been investigated. Strain technology can be used as an additional degree of freedom to enhance the carriers transport properties due to band structure changes and mobility enhancement. New concepts and novel device architectures that are based on strain engineering technology have been explored using TCAD modeling. Two approaches have been used in this study to generate the proper mechanical strain inside the device. The first approach was through introducing strain at the device’s base region using SiGe extrinsic stress layer. The second approach was through introducing strain at the device’s collector region using strain layers. The obtained results obviously show that strain engineering technology principle applied to BJT/HBT device can be a promising approach for further devices performance improvements

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6

Thai, Emily (Emily Sue). "TCAQ-based polymer for electrochemically mediated separations". Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111357.

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Thesis: S.B., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 35-36).
Redox-mediated separation systems offer the potential to efficiently desalinate water and to purify contaminated waste streams, among other health and environmental applications. A TCAQ-based polymer, unique for its two-electron redox reaction, was synthesized for use in redox-mediated separation systems, and its performance was quantified in low-concentration aqueous salt solutions. The polyvinyl ferrocene (PVF)//PTCAQ system displayed an ion adsorption capacity much higher than previously reported literature values for capacitive or redox deionization systems.
by Emily Thai.
S.B.

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7

Gappisch, Steffen. "TCAD-based development of a flash-EPROM technology /". [S.l.] : [s.n.], 1996. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11581.

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8

Tang, Jun. "Causal models for analysis of TCAS-induced collisions". Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/309134.

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Una sèrie de col·lisions aèries que van succeir durant un període d’uns 30 anys (1956-1986) van ser un dels principals motius pels quals l’Administració Federal d’Aviació (FAA) va prendre la decisió de desenvolupar i implementar un sistema de prevenció de col·lisions eficaç que actués com a últim recurs, quan es produís una fallada del servei de separació d’aeronaus per part del controlador de trànsit aeri (ATC). El Sistema d’Alerta de Trànsit i Anticol·lisió (TCAS) va ser desenvolupat per a aquest objectiu a partir d’una anàlisi completa de dades de vol. Com a resultat, la influència de TCAS en la seguretat del vol ha estat eficaç, beneficiosa i significativa en la reducció de la probabilitat de col·lisions. Els projectes Single European Sky ATM Research (SESAR) i Next Generation Air Transportation System (NextGen) pretenen millorar l’eficiència en la gestió del tràfic aeri (ATM) al mateix temps que es pretén reduir l’actual capacitat latent en el costat aire mitjançant la incorporació de noves tecnologies i procediments. En conseqüència, serà necessari investigar l’impacte en seguretat en augmentar la capacitat de l’espai aeri mitjançant una anàlisi exhaustiva i una avaluació efectiva del vol. En aquesta tesi, es proposen diversos models causals de colisions entre aeronaus per millorar el rendiment del TCAS tenint en compte el potencial efecte sobre el trànsit colindant, considerant escenaris futurs amb un nombre elevat de trajectòries. Els diferents models han estat especificats com a sistemes a esdeveniments discrets mitjançant el formalisme de Xarxes de Petri Acolorides. Mitjançant l’anàlisi de l’espai d’estat d’un volum d’espai aeri amb diverses aeronaus, els models desenvolupats avaluen els efectes dels diferents RAs generats pel TCAS sobre el tràfic col·lindant. Els models han estat validats utilitzant InCAS i ofereixen una perspectiva global de les dinàmiques que es generen, i una millor comprensió de les potencials col·lisions induïdes per a una millor valoració del risc de col·lisió. Com a resultat, els escenaris amb tràfic col·lindant que podrien iniciar col·lisions induïdes han estat identificats i caracteritzats. L’anàlisi quantitativa del factor de risc de col·lisions induïdes per TCAS ha estat realitzat per avaluar l’impacte de la demora del pilot per respondre als avisos TCAS durant el vol en escenaris d’alta densitat. Mitjançant l’ús de models estocàstics per representar la resposta del pilot s’han analitzat els diferents estats assolibles amb l’objectiu de generar resolucions cooperatives. En conseqüència, el rendiment de TCAS es podria millorar de forma innovadora sense necessitat d’introduir canvis rellevants en la lògica. Els models causals de col·lisions proposats poden ser utilitzats com a eines auxiliars en l’anàlisi d’escenaris de tràfic dens, i augmentar la capacitat de l’espai aeri, gestionant de manera eficient i segura un major nombre de vols. El present treball contribueix a continuar les investigacions en l’anàlisi de la seguretat dels conceptes ATM actuals i avançats, incloent les futures extensions de TCAS.
Una serie de colisiones en el aire que ocurrieron durante un período de unos 30 años (1956-1986) fueron uno de los principales motivos por los que la Administración Federal de Aviación (FAA) tomó la decisión de desarrollar e implementar un sistema de prevención de colisiones eficaz que actuara como último recurso, cuando se produjese un fallo del servicio de separación de aeronaves por parte del controlador de tránsito aéreo (ATC). El Sistema de Alerta de Tráfico y Anticolisión (TCAS) fue desarrollado para este objetivo a partir de un análisis completo de datos de vuelo. Como resultado La influencia de TCAS en la seguridad del vuelo ha sido eficaz, beneficiosa y significativa en la reducción de la probabilidad de colisiones. Los proyectos Single European Sky ATM Research (SESAR) y Next Generation Air Transportation System (NextGen) pretenden mejorar la eficiencia en la gestión del tráfico aéreo (ATM) al mismo tiempo que se pretende reducir la actual capacidad latente en el lado aire mediante la incorporación de nuevas tecnologías y procedimientos,. En consecuencia, va a ser necesario investigar el impacto en seguridad al aumentar la capacidad del espacio aéreo mediante un análisis exhaustivo y una evaluación efectiva del vuelo. En esta tesis, se proponen varios modelos causales de encuentro entre aeronaves para mejorar el rendimiento del TCAS teniendo en cuenta el potencial efecto sobre el tráfico colindante, considerando escenarios futuros con un número elevado de trayectorias. Los diferentes modelos han sido especificados como sistemas a eventos discretos mediante el formalismo de Redes de Petri Coloreadas. Mediante el análisis del espacio de estado de un volumen de espacio aéreo con varias aeronaves, los modelos desarrollados evalúan los efectos de los distintos RAs generados por TCAS sobre el tráfico colindante. Los modelos han sido validados utilizando InCAS y ofrecen una perspectiva global de las dinámicas que se generan, y una mejor comprensión de las potenciales colisiones inducidas para una mejor valoración del riesgo de colisión. Como resultado, los escenarios con tráfico colindante que podrían iniciar colisiones inducidas han sido identificados y caracterizados. El análisis cuantitativo del factor de riesgo de colisiones inducidas por TCAS ha sido realizado para evaluar el impacto de la demora del piloto para responder a los avisos TCAS durante el vuelo en escenarios de alta densidad. Mediante el uso de modelos estocásticos para representar la respuesta del piloto se han analizado los diferentes estados alcanzables con el objetivo de generar resoluciones cooperativas. En consecuencia, el rendimiento de TCAS se podría mejorar de forma innovadora sin necesidad de introducir cambios relevantes en la lógica. Los modelos de encuentros causales propuestos pueden ser utilizados como herramientas auxiliares en el análisis de escenarios de tráfico denso, y aumentar la capacidad del espacio aéreo, gestionando de manera eficiente y segura un mayor número de vuelos. El presente trabajo contribuye a continuar las investigaciones en el análisis de la seguridad de los conceptos ATM actuales y avanzados, incluyendo las futuras extensiones de TCAS.

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9

Saad, Yves. "TCAD-based three-dimensional modeling of nonvolatile memories /". Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17435.

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10

Ewert, Tony. "Advanced TCAD Simulations and Characterization of Semiconductor Devices". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6883.

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11

Falch, Markus. "Schottky Massenmessungen mit TCAP Datenaufnahmesystem am Experimentierspeicherring der GSI". Diss., lmu, 2000. http://nbn-resolving.de/urn:nbn:de:bvb:19-2950.

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12

Raghunathan, Uppili Srinivasan. "TCAD modeling of mixed-mode degradation in SiGe HBTs". Thesis, Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54315.

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13

Baravelli, Emanuele <1980&gt. "TCAD approaches to multidimensional simulation of advanced semiconductor devices". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1124/1/Tesi_Baravelli_Emanuele.pdf.

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Technology scaling increasingly emphasizes complexity and non-ideality of the electrical behavior of semiconductor devices and boosts interest on alternatives to the conventional planar MOSFET architecture. TCAD simulation tools are fundamental to the analysis and development of new technology generations. However, the increasing device complexity is reflected in an augmented dimensionality of the problems to be solved. The trade-off between accuracy and computational cost of the simulation is especially influenced by domain discretization: mesh generation is therefore one of the most critical steps and automatic approaches are sought. Moreover, the problem size is further increased by process variations, calling for a statistical representation of the single device through an ensemble of microscopically different instances. The aim of this thesis is to present multi-disciplinary approaches to handle this increasing problem dimensionality in a numerical simulation perspective. The topic of mesh generation is tackled by presenting a new Wavelet-based Adaptive Method (WAM) for the automatic refinement of 2D and 3D domain discretizations. Multiresolution techniques and efficient signal processing algorithms are exploited to increase grid resolution in the domain regions where relevant physical phenomena take place. Moreover, the grid is dynamically adapted to follow solution changes produced by bias variations and quality criteria are imposed on the produced meshes. The further dimensionality increase due to variability in extremely scaled devices is considered with reference to two increasingly critical phenomena, namely line-edge roughness (LER) and random dopant fluctuations (RD). The impact of such phenomena on FinFET devices, which represent a promising alternative to planar CMOS technology, is estimated through 2D and 3D TCAD simulations and statistical tools, taking into account matching performance of single devices as well as basic circuit blocks such as SRAMs. Several process options are compared, including resist- and spacer-defined fin patterning as well as different doping profile definitions. Combining statistical simulations with experimental data, potentialities and shortcomings of the FinFET architecture are analyzed and useful design guidelines are provided, which boost feasibility of this technology for mainstream applications in sub-45 nm generation integrated circuits.

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14

Baravelli, Emanuele <1980&gt. "TCAD approaches to multidimensional simulation of advanced semiconductor devices". Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1124/.

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Technology scaling increasingly emphasizes complexity and non-ideality of the electrical behavior of semiconductor devices and boosts interest on alternatives to the conventional planar MOSFET architecture. TCAD simulation tools are fundamental to the analysis and development of new technology generations. However, the increasing device complexity is reflected in an augmented dimensionality of the problems to be solved. The trade-off between accuracy and computational cost of the simulation is especially influenced by domain discretization: mesh generation is therefore one of the most critical steps and automatic approaches are sought. Moreover, the problem size is further increased by process variations, calling for a statistical representation of the single device through an ensemble of microscopically different instances. The aim of this thesis is to present multi-disciplinary approaches to handle this increasing problem dimensionality in a numerical simulation perspective. The topic of mesh generation is tackled by presenting a new Wavelet-based Adaptive Method (WAM) for the automatic refinement of 2D and 3D domain discretizations. Multiresolution techniques and efficient signal processing algorithms are exploited to increase grid resolution in the domain regions where relevant physical phenomena take place. Moreover, the grid is dynamically adapted to follow solution changes produced by bias variations and quality criteria are imposed on the produced meshes. The further dimensionality increase due to variability in extremely scaled devices is considered with reference to two increasingly critical phenomena, namely line-edge roughness (LER) and random dopant fluctuations (RD). The impact of such phenomena on FinFET devices, which represent a promising alternative to planar CMOS technology, is estimated through 2D and 3D TCAD simulations and statistical tools, taking into account matching performance of single devices as well as basic circuit blocks such as SRAMs. Several process options are compared, including resist- and spacer-defined fin patterning as well as different doping profile definitions. Combining statistical simulations with experimental data, potentialities and shortcomings of the FinFET architecture are analyzed and useful design guidelines are provided, which boost feasibility of this technology for mainstream applications in sub-45 nm generation integrated circuits.

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15

Cleveland, William Peter. "Improving pilot understanding of TCAS through the traffic situation display". Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/47726.

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The goal of this thesis is to improve pilot understanding of the Traffic alert and Collision Avoidance System (TCAS) by changing the Traffic Situation Display (TSD). This is supported by two objectives. The first objective is to create an integrated, realistic air traffic environment. This serves as an experimental platform for testing and evaluating future TCAS TSDs. The simulator environment includes a desktop flight simulator, background air traffic simulator, and intruder aircraft. The intruder aircraft uses seven dimensional waypoints to robustly follow trajectories and cause specific resolution advisories. Second, the relative benefits of, and potential concerns with, new TCAS TSDs are explored using a structured, iterative design process with subject matter ex- perts (SMEs). Incremental changes to the TSD were implemented into the simulator environment. SMEs evaluated the displays and potential points of confusion were identified. Several display features are discussed and implemented for future evaluations. These include boundary lines of TCAS variables depicted on the TSD and on a vertical situation display, speed lines which vary with the TCAS estimate of time to closest point of approach, and a prediction of the safe altitude target during a resolution advisory. Scenarios which may be confusing or misleading are discussed. These scenarios may be ameliorated or exacerbated by display features. This information is useful to guide both design and certification or operational approval and is a starting place for future TCAS experiments.

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16

Yeleswarapu, Krishnamurthy. "TCAD simulation framework for the study of TSV-device interaction". Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/51785.

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With the reduction in transistor dimensions to a few tens of nanometers as a result of aggressive scaling, interconnect delay has now become one of the major bottlenecks to chip performance. Secondly, interconnect power and area have both become a significant part of the total chip power and area respectively. These concerns have led to an effort to find a solution that would reduce interconnect delay and leakage, while also reducing the area they occupy in a chip, so that either the chip area could be reduced, or more functionality could be incorporated within a certain area. 3D integration, i.e., stacking of various sub-systems of a chip on top of each other, enables chip-makers to achieve higher packaging efficiencies, thereby reducing system cost, while also reducing delay (and thus increasing the available bandwidth). Through Silicon Vias (TSVs) have emerged as the key interconnect technology for 3D ICs, as they enable significant reduction in delay and leakage compared to wire-bonded dies, while also occupying less area in a package. They also enable stacking of sub-systems which differ in functionality, and stacking of multiple dies. Also, unlike wire-bond, dies need not be bandwidth limited by the number of wire bonds that can be made between two levels in a stack. While TSVs offer many advantages, one of the concerns when implementing a 3D system using TSVs is the mechanisms of interaction between a TSV and a device in its vicinity. Another concern is with regards to the interaction between the TSV and its surrounding material. The purpose of this thesis is to develop a TCAD framework for process and device co-simulation of a TSV transistor system to study the various mechanisms of interaction between them, as well as between the TSV and substrate. The utility of this tool has been demonstrated by studying two mechanisms of interaction, the effect of TSV-induced stress, and the effect of TSV-device electrical coupling, on the electrical performance of bulk NMOS and PMOS transistors. The results from 3D TCAD simulations suggest that designers can scale the keep out zone (KOZ) around TSVs more aggressively, allowing for more efficient utilization of silicon area, without a drastic performance penalty.

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17

Sa, Wanderley Pires de. "Reconstrução do equilíbrio no tokamak TCA/BR". Universidade de São Paulo, 1996. http://www.teses.usp.br/teses/disponiveis/43/43131/tde-12122013-162240/.

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A determinação precisa e rápida das configurações de equilíbrio Magnetohidrodinâmico (MHD) em tokamaks é de fundamental importância para o confinamento magnético do plasma. Através do conhecimento dos parâmetros que caracterizam este equilíbrio MHD é possível controlar o plasma durante a sua formação por processos de realimentação. Uma análise mais detalhada destes parâmetros é necessária, também, entre um disparo e outro, para a estruturação do experimento. Neste trabalho é investigada a reconstrução das configurações de equilíbrio MHD no tokamak TCA/BR a partir de medidas magnéticas externas, utilizando um método que permite uma rápida determinação dos parâmetros principais da descarga. A tese divide-se em duas partes. Na primeira, é apresentada a construção de um código de equilíbrio que resolve a equação de Grad-Shafranov para a configuração geométrica que caracteriza o tokamak TCA/BR. Na segunda, é descrito o processo de reconstrução do equilíbrio MHD através de medidas de campos e fluxos magnéticos externos ao plasma no TCA/BR, e utilizando o método de Função de Parametrização FP. Este método baseia-se no tratamento estatístico de um banco de dados simulados de configurações de equilíbrio, com o objetivo de obter uma expressão simples relacionando os parâmetros que caracterizam o equilíbrio e as medidas realizadas. Os resultados obtidos através da FP são comparados com os obtidos através de outros métodos convencionais.
The accurate and rapid determination of the Magnetohydrodynamic (MHD) equilibrium configuration in tokamaks is a fundamental subject for the magnetic confinement of the plasma. With the knowledge of characteristic plasma MHD equilibrium parameters it is possible to control the plasma position during its formation using feed-back techniques. It is also necessary an on-line analysis between successive discharges to program external parameters for the subsequent discharges. In this work it is investigated the MHD equilibrium configuration reconstruction of the TCA/BR tokamak from external magnetic measurements, using a method that is able to determine fastly the main parameters of discharge. The thesis has two parts. Firstly it is presented the development of an equilibrium co de that solves de Grad-Shafranov equation for the TCA/BR tokamak geometry. Secondly it is presented the MHD equilibrium reconstruction process from external magnetic field and flux measurements using the Function Parametrization FP method. This method is based on the statistical analysis of a database of simulated equilibrium configurations, with the goal of obtaining a simple relationship between the parameters that characterize the equilibrium and the measurements. The results from FP are compared with conventional methods.

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Badcock, Stephen G. "Viability study of SiGe/Si heterojunction MOSFET technology by computer simulation". Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324925.

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Velayudhan, Vikas. "TCAD study of interface traps-related variability in ultra-scaled MOSFETs". Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/400200.

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El trabajo desarrollado en esta tesis se ha enfocado en el análisis y estudio del impacto que tienen en la variabilidad de MOSFETs ultraescalados el número y la distribución espacial de las trampas interficiales. En los estudios realizados, el número de localizaciones en las que las trampas estaban ubicadas se varió, pero siempre se mantuvo la carga total constante, definiendo diferentes densidades de trampas según el número de localizaciones analizado. Inicialmente se realizaron simulaciones en 2D de trampas interficiales situadas a lo largo del canal del transistor y se analizó su influencia en Vth. Se analizaron los casos de una sola localización, analizando la influencia de la longitud de canal y tensión de drenador, 2 y múltiples localizaciones. Posteriormente, el análisis se extendió a simulaciones en 3D, simulando trampas interficiales distribuidas a lo largo y ancho del transistor. Finalmente, se analizó el efecto de trampas interficiales no solo en Vth si no también en Ion. Para tener una visión más realista del efecto de las trampas interficiales en la variabilidad del transistor MOSFET ultrescalado, se extendió el estudio a simulaciones en 3D de un dispositivo de WxL = 50nm x 20nm. Los resultados mostraron que la localización de las trampas a lo largo del canal tiene más influencia que su posición a lo ancho del canal. Además, para el caso de considerar dos trampas, se observó que si estaban muy juntas su influencia es menor que si están suficientemente separadas. Los resultados se interpretaron en términos de cambios en el área de barrera de potencial creados según la posición de las trampas. Se simularon dispositivos con diferente número de localizaciones en posiciones aleatorias y se observó un efecto ‘turn around’ en la dependencia de Vth (valor medio) y σVth. El incremento inicial en Vth se atribuyó a un incremento del área de la barrera efectiva con el número de localizaciones. El decremento posterior observado en Vth al aumentar el número de localizaciones se atribuyó a un aumento de la probabilidad de tener trampas muy cerca unas de otras resultando en una disminución del área de la barrera, junto con el escalado en carga en cada localización. También se observó que σVth sigue la ley de Pelgrom y que la anchura del dispositivo juega un papel dominante en esta dependencia. Por otro lado, también se ha observado que la distribución espacial de trampas afecta a la corriente Ion. Los resultados mostraron que la localización de trampas a lo largo del canal influye fundamentalmente en Vth, mientras que la distribución de trampas a lo ancho del canal afecta sobre todo a Ion. Estas dependencias explican las asimetrías encontrados en las características Id-Vg de los transistores. El trabajo se podría continuar analizando el impacto de distribuciones de trampas en condiciones dinámicas, como ocurre en los mecanismos de RTN o el BTI. La principal aplicabilidad de los resultados de esta tesis se sitúa en el campo de la fiabilidad de MOSFETs ultrescalados. Las aportaciones hechas en esta tesis contribuyen a entender el efecto del número distribución espacial de trampas interficiales, que pueden originarse con mecanismos que pueden reducir la fiabilidad como Bias Temperature Instabilities (BTI), Hot Carrier Injection (HCI) o Random Telegraph Noise (RTN), en la dispersión de las características de transistores MOSFET.
The work developed in this thesis has focused on the analysis and study of the impact on the variability of ultra-scaled MOSFETs due to the number and spatial distribution of interfacial traps. In the study, the number of locations where traps were located were randomly varied, but the total charge in the entire device was always maintained constant. Initially 2D simulations of interfacial traps located along the channel of the transistor and its influence on Vth was analyzed. The analysis was started with the case of a single location, analyzing the influence of channel length and drain voltage, and the case of 2 and multiple locations were analyzed. Subsequently, the analysis was extended to 3D simulations, simulating interfacial traps distributed across the transistor. Finally, the effect of interfacial traps was analyzed not only on Vth but also on Ion. For a more realistic vison of the effect of interfacial traps variability on ultra-scaled MOSFET transistors, the study was extended to 3D simulations of a device WxL = 50nm x 20nm. The results showed that the location of traps along the channel has more influence than its position at the edge of the channel. In addition, when the case of two traps were considered, it was observed that if they were close together their influence is less than if they were sufficiently separated. The results were interpreted in terms of changes in the area of potential barrier created by the position of the traps. Devices were simulated with different number of locations at random positions and compared to the 2D results, a 'turn around' effect was observed in the dependence of Vth (mean value) and σVth. The initial increase in Vth was attributed to an increase in area of the effective barrier with the increase in the number of locations. The subsequent decrease observed in Vth with the increase in the number of locations was attributed to an increased likelihood of having traps very close to one another resulting in a decrease in the effective area of the barrier, along with the charge scaling at each location. It was also noted that σVth follows the Pelgrom’s law and that the width of the device plays a dominant role in this dependence. Furthermore, it has also been found that the spatial distribution of the traps affects the Ion. The results showed that the location of traps along the channel fundamentally influences Vth, while the distribution of traps channel along the width affects mostly Ion. These dependencies explain the asymmetries found in the Id-Vg characteristics of transistors. The work could be continued by analyzing the impact of distributions of traps in dynamic conditions, as in the mechanisms of RTN or BTI. The main applicability of the results of this thesis lies in the field of reliability of ultra-scaled MOSFETs. The contributions made in this thesis contribute to understand the effect of the number and the spatial distribution of interfacial traps that can arise with mechanisms such as Bias Temperature Instabilities (BTI), Hot Carrier Injection (HCI) or Random Telegraph Noise (RTN) that can reduce device reliability and result in the dispersion of the characteristics of MOSFETs.

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20

Bäcker, Alexandra. "A TCAD analysis of long-wavelength vertical-cavity surface-emitting lasers". Konstanz Hartung-Gorre, 2009. http://d-nb.info/995591296/04.

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Billingsley, Thomas B. (Thomas Boyd). "Safety analysis of TCAS on Global Hawk using airspace encounter models". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35294.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 66).
The U.S. Air Force's RQ-4 Global Hawk unmanned aerial vehicle (UAV) is a high altitude, long endurance aircraft used for surveillance and reconnaissance. Because of the potential for close proximity to manned aircraft in civil airspace, collision avoidance is a major concern, and the Air Force is seeking to equip Global Hawk with the Traffic Alert and Collision Avoidance System (TCAS) to reduce the probability of mid-air collision. Currently, Global Hawk is equipped with a Mode S transponder and uses chase aircraft, ground observers and/or ground radar contact to comply with the collision avoidance requirement. In order to evaluate TCAS effectiveness, a fast-time simulation tool has been developed at MIT Lincoln Laboratory that computes the mean probability of a near mid-air collision for a large number of close encounters between two aircraft. Airspace encounter models enable sets of encounters to be simulated that are statistically representative of the aircraft encounters that actually occur in the airspace. The TCAS logic is implemented in the simulation tool and the aircraft responses during the encounters, with and without TCAS, are simulated in parallel.
(cont.) By observing measured vertical miss distance at the closest point of approach between the two aircraft, it is possible to quantify the reduction in collision risk provided by TCAS, termed the risk ratio. Global Hawk's flight characteristics differ from a conventional aircraft. Its mission profile through civil airspace includes slow, steep climbs and descents, and shallower turns than a conventional aircraft. Its vertical acceleration and climb rate limits can hinder its response to a TCAS resolution advisory (RA). Communication latency also may occur. For this thesis, encounter models were developed that reflect Global Hawk's flight characteristics. The new encounter models were then implemented in the simulation tool, and millions of encounters between Global Hawk and a conventional aircraft were simulated. These encounters were compared against encounters between two conventional aircraft to observe how Global Hawk's flight characteristics changed the effectiveness of TCAS. Assuming a standard pilot response to TCAS RAs, TCAS provided a significant safety improvement to Global Hawk over a Mode S transponder alone, yielding risk ratios in the range of 0.003 to 0.079.
(cont.) Global Hawk's flight characteristics generally caused a decrease in TCAS effectiveness from the original encounter models. Encounters were also simulated where Global Hawk's response to TCAS RAs was delayed by increasing amounts to simulate communication latency. A delay of approximately 15 seconds was tolerable before TCAS provided less safety than a Mode S transponder alone.
by Thomas B. Billingsley.
S.M.

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22

Coletty, Ione Margarida de Souza. "Transtorno de compulsão alimentar periodica (TCAP) e ansiedade em adolescentes obesos". [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/311922.

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Orientador: Francisco Baptista Assumpção Junior
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas
Made available in DSpace on 2018-08-05T02:48:41Z (GMT). No. of bitstreams: 1 Coletty_IoneMargaridadeSouza_M.pdf: 1079296 bytes, checksum: 46119b20dcac409419a9e003d2afffdd (MD5) Previous issue date: 2005
Resumo: Este trabalho teve como objetivo verificar a presença do Transtorno de Compulsão Alimentar Periódica - TCAP em adolescentes obesos e se existe alguma correlação entre este transtorno e a ansiedade. Para isto realizou-se um estudo de delineamento transversal, utilizando-se método quantitativo. Os instrumentos de pesquisa utilizados foram: entrevista para identificação do transtorno, segundo critérios do DSM-IV; Índice de Massa Corporal ¿ IMC; Escala de Compulsão Alimentar ¿ ECAP; e Inventário de Ansiedade Traço-Estado ¿ IDATE. Foram pesquisados 73 adolescentes obesos e com sobrepeso, com idade entre 11 e 18 anos respeitando sua ordem natural de procura ao Programa de Medicina Preventiva da UNIMED Baixa Mogiana. Os instrumentos permitiram avaliar as seguintes variáveis: idade, sexo, IMC, TCAP e Ansiedade Traço e Estado. Os sujeitos foram divididos em 2 grupos: com TCAP e sem TCAP (grupo-controle), e comparadas às demais variáveis entre eles. Os dados da pesquisa permitiram também avaliar a escolaridade destes sujeitos, que variou da 5a. série do ensino fundamental até a 3a. série do ensino médio. Os resultados tiveram análise estatística com testes não paramétricos e utilizando-se um nível de significância de 5%, com p-valor = 0,05. Os resultados evidenciaram que os índices de IMC e ansiedade-traço mostraram-se estatisticamente mais significativos no grupo com TCAP que no grupo sem TCAP, indicando uma presença maior de ansiedade e de obesidade nos adolescentes que apresentaram TCAP. Estes resultados encontraram semelhança com o de estudos anteriores e, apesar das limitações da pesquisa, podem ser indicativos de fatores de risco consideráveis para a obesidade e outros transtornos na adolescência. Podem também contribuir para um melhor conhecimento desta categoria diagnóstica mais recente que é o TCAP e de sua relação com a ansiedade nos adolescentes obesos
Abstract: This work had as objective to verify the presence of Binge Eating Disorder (BED) in obese adolescents and if it has some correlation with anxiety. For this accomplishment a cross-sectional study and a quantitative method was used. The research instruments used were: identification interview of BED, according to DSM-IV criteria; Body Mass Index (BMI); Binge Eating Scale (BES); and State-Trait Anxiety Inventory (STAI). Seventy three obese and overweight adolescents were researched, with age between 11 and 18 years old, respecting their natural order of searching to the Program of Preventive Medicine of UNIMED - Baixa Mogiana. The instruments allowed were used to evaluate the following variables: age, sex, BMI, BED and State-Trait Anxiety. The subjects were divided in 2 groups: with BED and without BED (group-control), and compared the other variables between the two groups. The data of the research also allowed to evaluate the education of the subjects: varying from the class V of secondary school and 3o. degree of high school. Over the results a statistical analysis with nonparametric tests were used, utilizing a level of significance of 5%, with p-value = 0,05. The results evidencied that the indexes of BMI and of anxiety-trait were significantly higher in the group with BED that in the group without BED, indicating that the adolescents with BED presented a larger tendency for anxiety and obesity that the subjects that didn't present BED. These results of this work are likeness the results of previous studies. And in spite of the limitations of the research, they can be indicative of considerable risk factor for the obesity and other disorders in the adolescence. They can also contribute to a better knowledgement of BED, this recent diagnostic category, and of their relationship with the anxiety in the obese adolescents
Mestrado
Ciencias Biomedicas
Mestre em Ciências Médicas

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23

De-Millo, Maxim. "Analys av TCAS trafikdisplay och förbättring av pilotens förståelse för systemet". Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-35807.

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Detta arbete berör den grafiska presentationen av antikollisionssystemet TCAS. TCAS är ett oberoende system som används för att piloten ska ha en bra översyn om trafiksituationen runt om sitt egna flygplan och vid ett farligt närmande få manöverrådgivningar för att undvika kollision. För piloten presenteras TCAS på en trafikdisplay som ofta är integrerad i någon annan display såsom navigationsdisplayen. Vid manöverrådgivning får man rådgivningar på en RAdisplay som ofta är integrerad i PFD. Syftet med detta arbete är att se om det går att förbättra den grafiska presentationen som piloten får, då det har visat sig att förståelsen för systemet ibland är bristande och vid hög trafikdensitet kan det bli rätt rörigt på trafikdisplayen. Detta är viktigt då piloten måste ha en bra uppfattning om trafiksituationen och kunna vara beredd på att göra en undanmanöver. Det är även viktigt att systemet är simpelt samtidigt som den ger all nödvändig information för att piloten ska vara medveten om trafiksituationen. Jag har i detta arbete utvecklat nya symboler genom att titta på riktlinjer för symboldesign. Symbolerna utvecklades med hänsyn till mänskliga faktorer och hur människan reagerar på olika faktorer i symbolen, som till exempel färg, uppmärksamhetsfaktorer och form. Det befintliga systemet testades i en flygsimulator. Detta gav en bra praktisk bild av hur systemet ser ut idag, och även en ide om hur jag ska utveckla de nya symbolerna. En intervju gjordes bland 6 kommersiella piloter, och utifrån deras feedback fick jag en förståelse för vad de ville ha för information på trafikdisplayen och vad de tyckte om det system jag utvecklat. Modifieringar gjordes och som resultat fick jag en simpel, men ändå informativ symboluppsättning. Den nya presentationen gav i överlag ett positivt intryck, trots att de piloter som blev intervjuade sa att de skulle kunna använda den nya designen, var de nöjda med det befintliga systemet. De tyckte dock att den nya designen kunde vara bra vid utbildning.

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24

Auburtin, Gautier Peyrelong Marie-France Dalhoumi Salah. "Les logiques sociales du travail coopératif assisté par ordinateur (TCAO/CSCW)". [S.l.] : [s.n.], 2004. http://www.enssib.fr/bibliotheque/documents/dessride/rrbauburtin.pdf.

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25

Zhang, Shuang. "Tandem Affinity Purification of Myogenin and Characterization of the Tcap Promoter". OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/205.

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Myogenesis is orchestrated by a family of four related bHLH transcription factors; MyoD, Myf5, Myogenin and Mrf4. The MRFs form heterodimers with E proteins and bind to the promoters or enhancers of muscle specific genes. Of these four, the Myogenic Regulatory Factor (MRF), myogenin, has been shown to play an important role during terminal differentiation of skeletal muscle. However, little is known about myogenin's function during myogenesis. In order to reveal myogenin associated factors, we performed tandem affinity purification of myogenin. The TAP purification with HEK293 cells elucidate that HEB and E2A are myogenin interacting factors. The expression of Tcap (Telethonin) is down regulated in myogenin null mice. However, beyond this, little is known about the regulation of the Tcap gene. In this work, we characterized the Tcap promoter by creating a luciferase reporter under the control of a minimal Tcap promoter that maintained the appropriate expression of Tcap in C2C12 myoblast cells. We performed luciferase assays with several Tcap reporter variants to characterize regulatory elements required for the expression of Tcap. Our results demonstrated that the Tcap promoter can be activated by exogenous myogenin or MyoD in NIH3T3 cells. In myoblasts, Tcap expression is greatly up regulated during differentiation, consistent with the expression of myogenin. Both of the two E boxes located at the Tcap promoter are required for the full Tcap activation in both NIH3T3 cells and C2C12 cells.

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26

Sampson, Brooke. "TCAP Assessment in Correlation with and as Compared by STAR Assessment". Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etd/3364.

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The purpose of the study was twofold. The first purpose of the study was to determine if a correlation existed between the Standardized Test for the Assessment of Reading (STAR), created and distributed by Renaissance, and the Tennessee Comprehensive Assessment Program (TCAP) Achievement Test in Math and Reading for grade 3, grade 4, and grade 5. The second purpose of this study was to evaluate the relationship between the percentile category of the STAR test and the TCAP test. The factor variable, identified as the percentile category, included three levels: Urgent Intervention, Intervention, and At/Beyond Benchmark. The dependent variable was the TCAP score. The study included 3rd-grade, 4th-grade, and 5th-grade students during the 2016-2017 school year who had taken the STAR reading and STAR math assessments and had taken the TCAP reading and TCAP math assessment. Based on the findings of this study, a strong correlational relationship does exist between the STAR and TCAP assessments. Overall, the strong correlation between the STAR and the TCAP were consistent across Math and Reading in 3rd, 4th, and 5th grades. Since the ANOVA was significant, a post hoc multiple comparisons was conducted to evaluate pairwise difference among the means of the three groups. Overall, the At/Beyond Benchmark group was significantly higher than both the Urgent Intervention group and the Intervention group in Math and Reading for 3rd grade, 4th grade, and 5th grade. There was not a significant difference between the Urgent Intervention group and the Intervention group, the exception was 5th grade math.

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27

Rodriguez, Axel. "Étude des mécanismes de déclenchement des Bits Collés dans les SRAM et DRAM en Environnement Radiatif Spatial". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTS032/document.

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Les résultats de différentes expériences du CNES (Centre National d’Études Spatiales) embarquées sur satellites montrent que des composants SRAM et SDRAM subissent des erreurs atypiques, qui se caractérisent par une fraction d’emplacements mémoire présentant des erreurs récurrentes. Ces erreurs non-catégorisées représentent la quasi-totalité des erreurs détectées sur ces mémoires. Une revue interne du CNES a déterminé que ces erreurs étaient dues aux radiations présentes dans l’environnement spatial (protons, électrons, ions lourds). Cette thèse s’attache à reproduire ces erreurs atypiques au sol en utilisant des moyens d’irradiation et des accélérateurs de particules, à les caractériser ainsi qu’à expliquer le mécanisme physique menant à l’apparition de ces cellules endommagées. Le mécanisme physique que nous proposons est cohérent avec les données obtenues sous faisceau de particules et soutenu par nos simulations de type TCAD
CNES’s onboard experiment results on several satellites have demonstrated that on SRAM and SDRAM memories, a fraction of words suffers from unknown errors that increase the afflicted words’ rate of error by orders of magnitude compared to other words. CNES’s experts found that these errors were due to the space radiation environment (proton, electrons, heavy ions).The main goals of this Ph.D. thesis are to successfully recreate such errors at ground level using irradiation facilities and particle accelerators, to investigate their behavior and finally, to submit a physical mechanism for memory cell degradation under irradiation, both coherent with experimental data and data obtained from TCAD simulations

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28

Gull, Ronald Dumeng. "TCAD based development of a polysilicon emitter transistor in a BiCMOS technology /". [S.l.] : [s.n.], 1996. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=11757.

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Viguié, Philippe. "Pilotage d'implémentations d'outils de TCAO au sein d'une organisation : une approche méthodologique". Phd thesis, Université Paul Sabatier - Toulouse III, 2010. http://tel.archives-ouvertes.fr/tel-00540561.

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Les technologies de la collaboration suscitent de nombreuses études sur la façon de concevoir et de développer des systèmes de Travail Coopératif Assisté par Ordinateur (TCAO). Néanmoins, les recherches relatives au pilotage du processus d'implémentation des outils de TCAO, dans le monde industriel, ne sont pas nombreuses. L'approche techno-centrée, valable pour les applications individuelles à des fins purement techniques, semble en décalage dans le cas de l'implémentation de ces outils où l'humain, l'organisation et la technologie doivent trouver un équilibre. Plusieurs auteurs ont décrit les problèmes rencontrés, d'autres ont proposé des approches sur la problématique de l'amélioration du processus d'implémentation. Une méthode abordable pour des non spécialistes du domaine reste nécessaire à proposer. Le but de ce travail est de mettre au point une méthode de pilotage du processus d'implémentation. Par ailleurs, la plupart des travaux se base sur une logique de conception alors que nous nous positionnons sur une logique d'acquisition et d'intégration des applications de TCAO, dans le domaine industriel. L'intérêt académique de cette recherche réside ainsi dans la nouveauté qu'elle propose en matière méthodologique. Notre contribution académique dans le domaine, est celle d'une proposition de méthode de pilotage sous forme de tableaux de bord. Basée sur les concepts Agile, notre méthode, dite « par grignotage » propose un suivi par étape. Chaque étape représente la gestion locale d'indicateurs d'implémentation regroupés en fonction d'un item (facteur de succès) issu des résultats connus de l'état de l'art et de ceux produits par des expérimentations menées sur une période de 3 ans au sein d'une grande banque régionale.

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30

Brunton, Jason A. "TCAD analysis of heating and maximum current density in carbon nanofiber interconnects". Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5495.

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Approved for public release; distribution is unlimited.
As devices shrink, the current density through interconnects increases proportionally making new materials a necessity for industry growth. Carbon nanofiber (CNF) and carbon nanotube's (CNT) potential for high current density make them a possible replacement for metal contacts. Learning the limitations of CNFs and CNTs is important if they are to be used in next-generation electronics. As current density increases, heat is generated throughout the CNF structure. This heating eventually leads to breakdown as the temperature reaches the bonding energy of the Carbon-Carbon (C-C) bond, the bond between two carbon atoms. The resultant reaction is the vaporization of the carbon, eliminating electromigration problems common with metal interconnects. The physics of breakdown of CNFs is poorly understood. The CNF interconnects' heating under a voltage sweep between two electrodes is modeled in this thesis. A working model was created with Silvaco ATLAS using experimental data provided by Santa Clara University (SCU). An analytical solution was found for the heat generation occurring within the device. The simulation does not show the breakdown occurring; instead, it accurately predicts the temperature and electrical characteristics of the device. This model will aid in the analysis of CNFs' reliability and potential future integration into the next generation electronics.

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31

Forbes, Elaine, Sian Nieduszynska, Fiona Brunton, Joanne Gibson, L. A. Glover y Ian Stansfield. "Control of gag-pol gene expression in the Candida albicans retrotransposon Tca2". BioMed Central, 2007. http://hdl.handle.net/10150/610060.

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BACKGROUND:In the C. albicans retrotransposon Tca2, the gag and pol ORFs are separated by a UGA stop codon, 3' of which is a potential RNA pseudoknot. It is unclear how the Tca2 gag UGA codon is bypassed to allow pol expression. However, in other retroelements, translational readthrough of the gag stop codon can be directed by its flanking sequence, including a 3' pseudoknot.RESULTS:The hypothesis was tested that in Tca2, gag stop codon flanking sequences direct translational readthrough and synthesis of a gag-pol fusion protein. Sequence from the Tca2 gag-UGA-pol junction (300 nt) was inserted between fused lacZ and luciferase (luc) genes in a Saccharomyces cerevisiae dual reporter construct. Although downstream of UGA, luc was expressed, but its expression was unaffected by inserting additional stop codons at the 3' end of lacZ. Luc expression was instead being driven by a previously unknown minor promoter activity within the gag-pol junction region. Evidence together indicated that junction sequence alone cannot direct UGA readthrough. Using reporter genes in C. albicans, the activities of this gag-pol junction promoter and the Tca2 long terminal repeat (LTR) promoter were compared. Of the two promoters, only the LTR promoter was induced by heat-shock, which also triggers retrotransposition. Tca2 pol protein, epitope-tagged in C. albicans to allow detection, was also heat-shock induced, indicating that pol proteins were expressed from a gag-UGA-pol RNA.CONCLUSION:This is the first demonstration that the LTR promoter directs Tca2 pol protein expression, and that pol proteins are translated from a gag-pol RNA, which thus requires a mechanism for stop codon bypass. However, in contrast to most other retroelement and viral readthrough signals, immediate gag UGA-flanking sequences were insufficient to direct stop readthrough in S. cerevisiae, indicating non-canonical mechanisms direct gag UGA bypass in Tca2.

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32

Shang, Junyi. "Experimentation and Multiphysical Modeling of Bioanalytical Microdevices". Thesis, 2019. https://doi.org/10.7916/d8-tcjf-z745.

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Bioanalytics involves quantitative measurements of complex biological samples that contain metabolites, DNA, RNA, and proteins. Efficient sample preparation for downstream analysis and sensitive detection of analytes can be achieved via bioanalytical microdevices. Fully realizing the potential of these devices requires tool characterization and bioprocess optimization, in addition to understanding device physics. Therefore, this thesis introduces multiphysical modeling and experimentation of microdevices, with applications to diabetes care and single-cell analysis. To understand the physics of viscometric glucose microsensors, this thesis presents a model of the sensor, which couples the fluid flow with vibrating diaphragms. The model is used to predict the sensor response to glucose via theory of squeeze-film damping and vibrations of pre-stressed plate. A first-principle-based model resulting from the theory can be evaluated from the device's geometric and material properties, and quantitatively determines the device response to vibrational excitations at varying glucose concentrations. Next, this thesis introduces a theoretical model for viscometric glucose microsensors that employ harmonic microcantilever oscillation in the sensing liquid. The presented model associates the unsteady Stokes equation with the motion of a bounded viscous liquid to understand the hydrodynamic impact on the cantilever. With a proper consideration of the viscosity and bounded geometry of liquid media, the model relaxes the thin-film assumption required for the diaphragm-based model, enabling an accurate representation of fluid-structure interactions based on fundamental structural vibration and fluid flow equations. Next, this thesis presents an experimental exploration of a hydrogel-based affinity microsensor for glucose monitoring via dielectric measurements. The microsensor incorporates a synthetic hydrogel that is attached to the device surface via in situ polymerization, which eliminates mechanical moving parts required in the viscometric glucose sensors. Changes in the dielectric properties of the hydrogel when binding reversibly with glucose molecules have been measured using a MEMS capacitive transducer to determine the glucose concentration. Experimental results demonstrate that in a glucose concentration range of 0–500 mg/dL and with a resolution of 0.35 mg/dL or better, the microsensor exhibits a repeatable and reversible response, and can potentially be useful for continuous glucose monitoring in diabetes care. Additionally, this thesis presents a microfluidic preprocessing method that integrates single-cell picking, lysing, reverse transcription and digital polymerase chain reaction to enable the isolation, tracking and gene expression analysis at single-cell level for individual cells. The approach utilizes a photocleavable bead-based microfluidic device to synthesize and deliver stable complementary DNA for downstream gene expression analysis, thereby allowing chip-based integration of multiple reactions and facilitating the minimization of sample loss or contamination. Finally, this thesis ends with concluding remarks and directions of future work towards continuous glucose monitoring and high-throughput single-cell genetic analysis.

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33

Chia-JungLee y 李嘉蓉. "TCAS Solution for General Aviation". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/38916699210947276455.

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碩士
國立成功大學
民航研究所
103
The National Airspace System (NAS) will change dramatically over the next 20 years. The demand of the airspace will increase rapidly, especially the usage of general aviation (GA), while the Small Aircraft Transport System (SATS) provides alternatives in air travel. As a result, collision avoidance system will play an important role for the aviation safety in the future. Varieties of conflict detection and resolution (CD＆R) were published under two and three maneuvering dimensions. The demand of airspace increases, the probability of mid-air conflict also rises. This study focuses on efficient collision avoidance logic for GA based on ADS-B for NextGen. Heading change of horizontal resolution is more suitable for small GA flying in lower altitude in this thesis. Simulations using real flight data are tested to verify the effectiveness of the proposed algorithm.

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34

WANG, CHUN-CHIEH y 王俊傑. "Tcad Power MOS simulated and research". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/04794841458441132492.

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碩士
明新科技大學
電子工程研究所
103
Power MOSFET is provided with such characteristics as a high resistance, a fast switching speed, a wider safe working area and a better thermal stability, etc., being extensively applied to such fields as switch power, etc. This paper analyzes various characteristics of VDMOS by means of Tcad software, and finds out the design method of key structure parameters. In addition, it also provides a kind of new trench – plane grid power MOSFET structure (TrenchMOS) and analyzes various characteristics of the new structure. The content of the major study shall be as follows: It studies various characteristics of VDMOS. In the VDMOS structure, the high resistance to pressure requires VDMOS to be provided with a thicker drift region with low concentration, and a shorter grid length. However, accompany the increase of the thickness of drift region, the reduction in concentration, and the decrease in gate length, the electric resistance of the drift region and JFET region would increase, leading to the increase of on-resistance and the increase of power consumption in the conduction state. Therefore, an irreconcilable contradiction would form between the on-resistance and the puncture voltage. A kind of new trench – plane grid power TrenchMOS structure is provided, an analysis as well as simulation is engaged concerning the structure characteristics of TrenchMOS, and a comparison is conducted with the VDMOS structure. The lead-in of trench eliminates the impact of the spacing of the drift region towards the puncture voltage and the on-resistance, making the TrenchMOS to be provided with a better blocking characteristic and a conduction characteristic.

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35

HO, RONG-SON y 何榮森. "TCAM aware routing algorithm in SDN". Thesis, 2018. http://ndltd.ncl.edu.tw/handle/83yfys.

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碩士
國立中正大學
通訊工程研究所
107
With the increasing number of users and the growth of data volume beyond the development speed of hardware vendors, the Software-Defined Network(SDN) has emerged to enable network administrators to flexibly modulate the network switches to meet the QoS and security requirements of the network application according to specific network conditions. When the controller receives a new service application request, it configures a flow entry in the "Flow Table" of the SDN switch along the path. When the ternary content addressable memory (TCAM) used to store the flow entry is insufficient, the new service application request will be blocked, resulting in low availability network security problems This paper proposes the "Minimum Block Rate Algorithm (MBRA)" method to solve this problem. The proposed algorithm considers the usage rate of SDN switch link and TCAM, and MBRA selects a feasible path. Further, this method uses rule sharing technique to reduce the usage of TCAM. Experiment shows that MBRA can achieve lower service block rate and lower maximum TCAM usage than existing works.

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36

Wan-JuHsieh y 謝宛儒. "Taipei TCA Flow Monitor". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/24492764998681492259.

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碩士
國立成功大學
民航研究所
98
The interactions between Taiwan and China have become more frequent via air transport since agreement of cross strait being signed. This brings in a large number flight demand being increased rapidly. Most flights are operating in TPE and TSA to result in flow congestion in Taipei TCA. The flow monitor is proposed to provide the predicted sequence of inbound and outbound aircrafts with minimum separation of Taipei TCA to focus on the increasing air flow from north. A case study has been simulated under heavy flow condition. FDP data from SAR are applied to estimate the time of feeder gates, last merge points, and landing further possible delay time. ATC indicates vectoring aircrafts according to predict sequence by executing ground holding and speed adjustment. Airborne holding is most avoided. The flow monitor can be used in approach control region and can efficiently reduce the probability of congestion in the busy Taipei TCA.

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37

Ju, Yan-Yun y 朱燕雲. "Fast TCAM Update Schemes for Packet Classifiers". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/rk6sr9.

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碩士
國立中興大學
資訊科學與工程學系
103
Ternary content addressable memory (TCAM) is a widely used technology for network devices to perform packet classification. TCAM can compare all entries simultaneously and takes only one access to get the first matching entry. However, managing rules in TCAM is quite complicated for supporting rule updates. To ensure the correctness of search results, TCAM management must maintain the order of entry locations for the updated entries. Moreover, the number of TCAM entry movements would also affect the search performance since an updated TCAM should be locked. In this paper, we propose a fast TCAM update scheme, namely TCAM Update using Substitute Chains (TUUSC). TUUSC reduce the TCAM update cost by minimizing the number of entry movements. We also present an approach, which makes use of extra TCAM entry to shorten chain length. The approach may split several rules in a chain into disjoint pieces to cut the chain into two shorter chains. In our experiments, updating rules using TUUSC can efficiently decrease the cost of TCAM movement. Thus, TUUSC can support more than one thousand updates per second for most classifiers. The chain-cuts approach also shortens chains with reasonable cost. Combining both proposed approaches can provide better update performance.

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38

Lin, Hsin-Tsung y 林欣璁. "A Hybrid Scheme for TCAM-based Classification". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/31107774668016484186.

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碩士
國立中興大學
資訊科學與工程學系
100
Ternary content addressable memory (TCAM) is a widely used technology for network devices to perform packet classification. TCAM can search all ternary entries simultaneously, thus, it only takes one access to get the first matching entry. It has several disadvantages, such as high power consumption, costly implementation and the inefficiency of range representation. Because of the rapid growth of the Internet applications, single-match packet classification is not capable of support multifunction network devices which need multi-match packet classification. Accordingly, several researches, such as multi-match using discriminator (MUD) and geometric intersection (GI), focus on improving the performance of TCAM-based multi-match packet classification. MUD has superior space performance and uses multiple memory accesses to find all matching entries. GI only needs one memory access to find the first match and its corresponding match list; however, GI usually occupies much more TCAM entries than MUD. In this paper, we present a hybrid scheme which combines two methods mentioned above. The hybrid scheme uses available TCAM entries to reduce memory access times. By using the properties of GI properly, our scheme not only fully utilizes the space of TCAMs to achieve a better speed performance.

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39

Chen, Jin-Hao y 陳金昊. "Vertical Partial Control TCAM Design and Implementation". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/09431620834989781409.

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碩士
國立中興大學
資訊科學與工程學系
102
Ternary Content Addressable memory (TCAM) is widely used in the routing table of the network router. Besides the dynamic power dissipated in?active mode, however, TCAM also consumes?large amount of leakage power in standby mode. In this paper, we propose the vertical partial control (VPC) technique to reduce the?leakage power consumption of TCAM.?Based on the vertiacally continuous "don''t care" feature shown in the routing table, the VPC technique uses segmentation method to?reduce the leakage power dissipated in the TCAM celles with "don''t care" mask. For a 128x32-bit TCAM array, using TSMC 0.18um technology process the simulation results show that the VPC?technique can reduce the?leakage power consumption by 14.24% compared to the conventional TCAM design.

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40

Agrahari, Shashank. "Designing of Feeding Networks for TCAS Antenna". Thesis, 2018. http://ethesis.nitrkl.ac.in/9662/1/2018_MT_216EE1471_SAgrahari_Designing.pdf.

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The Traffic Alert And Collision Avoidance System (TCAS) has had extraordinary success in reducing the risk of mid air collisions. Now mandated on all large transport aircraft, TCAS has been in operation for more than a decade and has prevented several catastrophic accidents. TCAS is unique decision support system in the sense that it has been widely deployed and is continuously exposed to a high tempo, complex air traffic systems. This report presents the designing of feeding network for TCAS system.We have designed the feeding network where input power will be switched between two ports of antenna equally and in different ratio and this can be implemented by terminating two stubs of the design with varactor diodes which works as avariable capacitor and switched on and off according to the condition .with correct choice of bias voltage it is possible to realize equal as well as unequal power division ratios between four output ports. The design frequency is chosen 1.06GHz as centre frequency. Simulation part is done on HFSS with Rogersduroid 5880 substrate with dielectric constant(ξ) = 2.2 .Varactor diodes are simulated by fixing the value of junction capacitance corresponding to maximum reverse bias which is 0.16 pF and capacitance corresponding to maximum forward bias will be 2.25 pF and value of R= 4.8Ω and inductor (L)= 1 nH where R and L will be same for both of the cases. We have simulated the design and analyzed the reflection coefficients(S55,S22,S33,S44,S11) and transmission coefficients (S15,S12,S13,S14 etc) where the values of these coefficients are according to the condition.

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41

Faezipour, Miad. "High-speed multi-match packet classification using TCAM /". 2006. http://proquest.umi.com/pqdweb?did=1232421491&sid=1&Fmt=2&clientId=10361&RQT=309&VName=PQD.

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42

Qin, Jingsheng. "Interworking of TCAP/SS7 and TCP/IP networks". 2002. http://hdl.handle.net/1993/19707.

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43

Chang, Kae-Wei y 張剴為. "Five-Dimensional Packet Classification Using 2-Level TCAM". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/87619889251739272139.

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碩士
國立成功大學
資訊工程學系碩博士班
96
The Internet is growing very rapidly. There are more and more high-quality Internet services and network applications are demanded in modern-day router, such as quality of service (QOS), security, and multimedia communication…etc. The packet classification is a proposed function for these demands. In order to classify a packet to a particular flow, the router must perform a search over a set of rules using multiple fields of the packet’s header as the search key. Traditionally, ternary content addressable memory (TCAM) has been adopted to solve the IP lookup problem due to their ability to perform fast and parallel searching. TCAM is very suitably for storing prefix. Because it can store three logic states (1, 0, don’t care) in a TCAM cell. But in five dimensional packet classification, it contains two fields arbitrary rang. In this situation, we may need many TCAM entries to store a classification rule. In this paper, we propose 2-Level TCAM architecture and relative complete method and strategy for five-dimensional packet classification. The basic idea of our scheme is that we duplicate the address space and we develop a strategy to group all packet classification rules. Besides, we also devise a method to trim the packet classification rules to help us to achieve our goal. Finally, in our proposed scheme, we can keep the advantage of TCAM and we won’t result in large number of packet classification rules.

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44

Liu, Jen-Hao y 劉人豪. "TCAM-based Multimatch Packet Classification with Hybrid Algorithms". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/19055445961828811529.

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碩士
國立中興大學
資訊網路多媒體研究所
98
As network intrusion detection system, virtual private network and Quality of Service (QoS) of various types of network applications increased rapidly, packet classification plays an important role in routers, and also support to make multi-match classification. However, implementation of multi-match classification is quite time-consuming for search, so we use TCAM to achieve multi-match classification, but the characteristics of TCAM supports only a single-match classification. In order to TCAM supports multi-match classification, rules will be added to the TCAM or increase number of TCAM accesses, therefore we will face the TCAM space consumption and decline of overall search speed. This paper presents the TCAM-based multi-match packet classification with hybrid algorithms, the rule set in the database using ABV to implement, and the other of rule set using geometric intersection or MUD to implement. The simulation results show that the TCAM for multi-match classification could be more efficient, and reduce the TCAM space consumption and speed up the overall search.

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45

Su, Cheng-Chien y 蘇正建. "Compression Techniques for Packet Classification Table in TCAM". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/68566655153601726941.

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碩士
國立成功大學
資訊工程學系碩博士班
93
Packet classification is an enabling function for a variety of Internet applications including Quality of Service, security, monitoring, and multimedia communications. In order to classify a packet as belonging to particular flow or set of flows, network nodes must perform a search over a set of filters using multiple fields of the packet as the search key. In general, there have been two major threads of research addressing packet classification: software and hardware. A Ternary Content Addressable Memory (TCAM) is a hardware solution for packet classification. 　　When we store the classification tables in TCAM, it will waste too much TCAM space since the port fields of the classification tables are arbitrary ranges. In the worst-case, it needs O(W) prefixes for a range in W-bit address space. Consider the standard 5-tuple rule tables in which source and destination ports are ranges. The worst-case number of prefix entries is O(nW2) if we store n 5-tuple rules in TCAM. For efficiently using the TCAM space, we need to compress the classification table in an efficient way. 　　In this thesis, we propose a scheme that can compress the TCAM space efficiently. The scheme first re-encode the port field of the classification tables, hence, we can use less number of bits to represent the port field. Moreover, each arbitrary range in port fields can be stored in only few TCAM entries. Experiment results conducted according to nine synthetic classification tables indicate our scheme save 67-83 percent of the TCAM space. In worst case, the TCAM storage complexity is reduced from O(nw2) to O(nlog2n).

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46

Kao, Yen-Kuo y 高延國. "Two level TCAM reduction architecture for IP lookup". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/49377210892191785303.

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碩士
國立成功大學
資訊工程學系碩博士班
93
In recent years using TCAM in lookup design becomes more and more popular. TCAM provide a fast and convenient solution for IP lookup problem. But the BGP table in the core router today often has more than 100k prefixes, so we will need the same large TCAM entries to store the routing table. Unfortunately, when enabling too many TCAM entries together will bring large power consumption and result in system over hot. And the over hot situation may block the regular system work. 　To avoid the over hot situation, we try to cut down the power consumption by reducing the TCAM entry in our design. We propose a two level architecture hybrid of TCAM and DRAM for IP lookup problem. According to our experiment result, our scheme only needs 2% TCAM entries rather than purely using TCAM to storing the routing table. It also means our architecture is less power consumption than tradition TCAM lookup design for the same routing table. Contrast with other architectures, our design make sure the requirement of TCAM entries will not linearly increase with the routing table growing. And by using mask extension and partitioning sub-TCAM steps, we can exactly control the enable TCAM entries and ensure the power consumption under the power restriction. At last, our architecture only needs one TCAM memory access and two DRAM memory accesses to finish the IP address lookup for each incoming IP packet.

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47

Lin, Kung-Hsien y 林恭賢. "A TCAD Simulation Study for Negative Capacitance FinFET". Thesis, 2016. http://ndltd.ncl.edu.tw/handle/46177385737499572894.

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碩士
國立中興大學
電機工程學系所
105
As devices scale down, VDD is scaled consistently due to power reduction. The subthreshold swing (S.S.) with 2.3KbT/decade for MOSFET in room temperature restricts the switch characteristics. To overcome such limits, a lot of researchers proposed to improve such a situation by connecting metal-insulator-metal (MIM) negative capacitance with ferroelectric materials (FE) as the dielectric layer in series and stacking on the gate. Such an advantage not only could reduce the power dissipation in steady state but also could be rapidly turned on under low voltage. 　　TCAD simulation is applied to study the device characteristics of NC-FET in this study. HZO is used for the FE layer, and the structure is 3D SOI FinFET. In this study, analytic functions are established for directly fitting the voltage gain experimental data of NC-FET. The data from two different annealing temperatures are utilized, with interpolation and extrapolation, for predicting the voltage gain from other annealing temperatures. The gate voltage with/without taking the NC effect into account is put in the TCAD simulator to simulate the ID-VG characteristics. The proposed approach could predict the ID-VG characteristics of NC-FinFET under different annealing temperatures and could be expanded to transistors with other structures, such as Bulk FinFET or Nanowire transistor, and distinct ferroelectric materials. Such an analytical model could also be established on the SPICE circuit simulation in the future to simulate the characteristics of NC-FET being applied to circuit design. Key word：NC、SOI FinFET、FE、S.S.、Nanowire transistors

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48

Kuang, Weiwei. "TCAD simulation and modeling of AlGaN/GaN HFETs". 2008. http://www.lib.ncsu.edu/theses/available/etd-03242008-155836/unrestricted/etd.pdf.

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49

Tzu-WenHung y 洪子雯. "ADS-B utilization into TCAS for General Aviation". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/30183468832647819309.

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碩士
國立成功大學
航空太空工程學系碩博士班
101
A new generation of traffic alert and collision avoidance systems based on the Global Positioning System (GPS) and Automatic Dependent Surveillance Broadcast (ADS-B) is introduced. The objective of the system is to prevent and alert pilot of the incoming potential collision since the flourish of the General Aviation and the Small Aircraft Transportation System has been practiced. This thesis is based on the ADS-B and GA maneuvers. The algorithm is designed to takes angle selections first according to the intruder heading and position that can reduce the nuisance alert occur. The detection algorithm has three sizes of area: Proximate Advisory, Traffic Advisory and Resolution Advisory. In each area the algorithm will provide an advisory for pilot to refrain from mid-air collision. The relationships between turn angle, horizontal miss distance (HMD) are calculated and analyzed to find a resolution when the intruder aircraft enters the detected range. Using encounter models under VFR to evaluate the performance of the algorithm, the resolution should follow the VFR and priority in different situation. The trajectories of the algorithm output will be shown at the end of this thesis.

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50

Fan, Sheng-Hsin y 范聖欣. "Low Power TCAM Design using Segmented-Precharge Technique". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/60024472384549794681.

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碩士
國立臺灣大學
資訊工程學研究所
99
Due to the characteristic of high-speed search in Ternary Content Addressable Memory (TCAM), it plays an important role in many high-speed devices, however it consumes too much power. The power consumption in conventional NOR-type TCAM is mainly from the dynamic power consumption, in which precharging all the match lines and discharging mismatched match lines during a search operation. Since the number of mismatched match lines is much more than the matched ones, most of the match lines are discharged leading to high power consumption. In this thesis, based on the characteristic of IP prefix stored in TCAM, the mask bit “0” has a continuity property when “0” appears. Therefore, we proposed a method called segmented-precharge technique in TCAM to reduce dynamic power consumption. The experimental results show that the proposed TCAM design with 4 segments is the most appropriate considering power and delay, which has 23.68% power saving and 0.74ns delay in average-case compared to the conventional TCAM.

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