Dissertations / Theses: 'LEMS'

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Wilding, Samuel E. "Expanding Lamina Emergent Mechanism (LEM) Capabilities: Spherical LEMs, LEM Joints, and LEM Applications." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2903.

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Lamina Emergent Mechanisms (LEMs) are a class of compliant mechanisms that can be manufactured from sheet goods and possess motion out of the plane of fabrication. LEMs can be designed to perform sophisticated motions. This thesis expands LEM understanding and increases the ability to utilize them in applications by introducing the fundamentals of spherical LEMs, creating joints suitable for LEMs, and providing an example of a LEM application. In this thesis, the fundamentals of spherical LEMs are developed. This includes classification of all possible spherical 4R LEMs and a discussion of the motion characteristics of the various mechanisms. The motion characteristics associated with spherical 4R LEMs are then used to predict the motion of spherical 6R LEMs and arrays of spherical LEMs. Multiple spherical LEM prototypes are shown and discussed. A common difficulty of working with compliant mechanisms, especially LEMs, is creating suitable joints. There is often a trade off between flexibility in the desired direction of deflection, and stiffness in directions of undesired deflection. For this thesis, LEM joints that possess higher off-axis stiffness, especially in tension and compression, than previous designs were developed: the I-LET, the T-LET, and the IT-LET. Joint geometries were optimized and then modeled in commercial finite element analysis (FEA) software capable of nonlinear analysis. These models were used to predict the bending of tensile/compressive stiffnesses of the joints. As a benchmark, lamina emergent torsional (LET) joints were modeled and optimized for maximum tension and compression loading while maintaining the same bending stiffness as the joint being compared. Mechanisms that utilized the new joints were created and are briefly discussed. The use of these joints allows for minimized parasitic motion under tension and compression loads and expands the capability of LEM joints. The Lens Lift™ was developed to demonstrate an application of LEMs. The Lens Lift™ is a LEM device that allows for easier and more sterile use of disposable contact lenses. It possesses a monolithic structure and can be fabricated using simple manufacturing processes. As the contact lens user opens the blister pack used to store the lens, the lens is lifted out of the pack and presented to the user. The user can then lift the lens with one touch and place it in the eye. A provisional patent has been filed for the device and the device currently being evaluated by a major contact lens manufacturer for further development.

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Villanueva, Marta Janer. "A population study of genetic susceptibility to the autoimmune myasthenias." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294378.

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Brady, John Joseph. "VAPORIZATION OF BIOLOGICAL MACROMOLECULES USING INTENSE, ULTRAFAST LASERS: MECHANISM AND APPLICATION TO PROTEIN CONFORMATION." Diss., Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/211496.

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Chemistry
Ph.D.
This dissertation details the design and implementation of a state-of-the-art ambient trace analysis technique known as laser electrospray mass spectrometry. This novel technique utilizes an intense, nonresonant femtosecond laser pulse to transfer nonvolatile, fragile molecules into the gas phase from various substrates. The vaporized analyte is subsequently captured, solvated and ionized in an electrospray plume enabling mass analysis. Laser electrospray mass spectrometry is capable of analyzing samples in the liquid or solid states, mass spectral imaging of adsorbed molecules and detecting low vapor pressure analytes remotely. Experiments with biomolecules and pharmaceuticals, such as vitamin B12 and oxycodone, have demonstrated that the nonresonant femtosecond laser pulse allows for coupling into and vaporization of all molecules. This implies that sample preparation (elution, mixing with matrix and choosing samples with a particular electronic or vibrational transition) is not necessary, thus creating a universal mass analysis technique. Investigations using low vapor pressure molecules, such as lipids and proteins, led to the discovery that unfragmented molecules are transferred into the gas phase via a nonthermal mechanism. The laser electrospray mass spectrometry technique has allowed for the nonresonant femtosecond laser vaporization and mass analysis of trace amounts of a nitro-based explosive from a metal surface. The vaporization of unfragmented explosive molecules from a surface facilitates the identification of the explosive, reducing the probability of false positives and false negatives. In addition, this "soft" vaporization of molecules using nonresonant femtosecond laser pulses allows for protein to be transferred from the condensed phase into the gas phase without altering the molecule's structure, enabling ex vivo conformational analysis and possible disease typing.
Temple University--Theses

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Cotte, Philippe. "Le projet WA105 : un prototype de chambre à projection temporelle à argon liquide diphasique utilisant des détecteurs LEMs." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS246/document.

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Le projet WA105/ProtoDUνE-DP est une expérience de prototypage qui a pour objectif de tester la technologie de Chambre à Projection Temporelle à Argon Liquide Diphasique (DLArTPC) à grande échelle dans le but de l'utiliser dans la future expérience de physique des neutrinos DUνE. Prévue fin 2026 aux USA, DUνE vise à déterminer l'ordre des masses des neutrinos ainsi que la violation de CP dans le secteur leptonique. Le travail de cette thèse s'oriente dans un premier temps autour des tests et simulations effectués sur les éléments de détection et d'amplification des détecteurs de WA105. Dans un second temps, la thèse s'oriente autour de l'analyse des traces de muons cosmiques vues par un premier prototype de 4t, opéré en 2017 au CERN. La technologie DLArTPC est une variante de la technologie LArTPC permettant une amplification des électrons extraits de la phase liquide à la phase gazeuse. Les amplificateurs d'électrons (LEMs) sont des plaques de PCB de 50x50cm² épais de 1mm, percés de 400k trous de 500 microns de diamètre, recouvertes de chaque côté par une mince couche de cuivre. Une différence de potentiel de l'ordre de 3kv permet d'atteindre un gain supérieur à 10. Une partie du travail de cette thèse a consisté à simuler la dérive des électrons à travers ces LEMs afin d'étudier les efficacités de collection de charge. Une autre partie de cette thèse a consisté à mesurer les caractéristiques importantes (épaisseur, tenue en tension) des amplificateurs destinés au démonstrateur de 300t de WA105, dont la mise en route a été effectuée fin août 2019 au CERN. Le gain est une des caractéristiques principales d'une DLArTPC, et il a été étudié dans le prototype de 4t grâce à la détection de muons cosmiques. Des comparaisons sont effectuées avec les résultats d'un prototype de 3L datant de 2014, et un programme de reconstruction de trace dédié a été développé pour traiter certains événements bruités. Le travail effectué dans cette thèse a permis de mieux comprendre le fonctionnement des DLArTPCs, notamment en ce qui concerne l'aspect multiplication et dérive des électrons. Ces connaissances seront importantes lors de l'opération du démonstrateur de 300t au CERN, ainsi que lors de l'exploitation du module DLArTPC de DUνE
The WA105/ProtoDUνE-DP project is a prototyping experiment which goal is to test the Double Phase Liquid Argon Time Projection Chamber (DLArTPC) technology at large scale, to use it in the future neutrinos physics experiment DUνE. Scheduled for the end of 2026 in the USA, DUνE aims at measuring the neutrinos mass ordering and the leptonic CP symetry violation. The first part of this thesis is dedicated to tests and simulations of the detection and amplification elements of the WA105 detectors. The second part is focused on the analysis of cosmic muon tracks seen by a first prototype of 4t, operated at CERN in 2017. The DLArTPC technology is a variation of the LArTPC technology allowing for the amplification of the electrons extracted from the liquid phase to the gas phase. The Large Electron Amplifiers (LEMs) are 50x50cm² PCB plates with a thickness of 1mm, pierced by 400k holes of 500 microns diameter, covered on each side by a thin layer of copper giving a gain superior to 10. Part of this thesis work is about the simulation of electrons drifting through those LEMs to study the charge collection efficiencies. Another part of this thesis is about the measurement of important caracteristics (thickness, voltage stability) of the LEMs that are used in the 300t demonstrator of WA105, which commissionning was done in the end of August 2019. The gain is one of the main caracteristics of a DLArTPC, and it has been studied in the 4t prototype by detecting cosmic muons. Comparisons are done with previous results from 2014 from a smaller prototype of 3L, and a dedicated reconstruction program was created to analyse noisy events. The work done in the thesis allowed for a better understanding of DALrTPCs, mainly on the multiplication and drift of electrons. This knowledge will be important during the operation of the 300t demonstrator at CERN, and during the operationg of the DLArTPC module of DUνE

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Greenberg, Holly. "The Application of Origami to the Design of Lamina Emergent Mechanisms (LEMs) with Extensions to Collapsible, Compliant and Flat-Folding Mechanisms." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3210.

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Lamina emergent mechanisms (LEMs) are a subset of compliant mechanisms which are fabricated from planar materials; use compliance, or flexibility of the material, to transfer energy; and have motion that emerges out of the fabrication plane. LEMs provide potential design advantages by reducing the number of parts, reducing cost, reducing weight, improving recyclability, increasing precision, and eliminating assembly, to name a few. However, there are inherent design and modeling challenges including complexities in large, non-linear deflections, singularities that exist when leaving the planar state, and the coupling of material properties and geometry in predicting mechanism behavior. This thesis examines the planar and spherical LEMs and their relation to origami. Origami, the art of paper folding, is used to better understand spherical LEMs and flat-folding mechanisms in general. All single-layer planar four-bar LEMs are given with their respective layouts. These are all change-point pinned mechanisms (i.e. no slider cranks). Graph representations are used to show the similarities between action origami and mechanisms. Origami principles of flat-folding are shown to be analogous to principles of mechanisms including rules for assembly and motion.

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Albrechtsen, Nathan Bryce. "Identifying Potential Applications for Lamina Emergent Mechanisms and Evaluating Their Suitability for Credit-Card-Sized Products." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2361.

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Lamina emergent mechanisms (LEMs) are a maturing technology that is prepared for commercial implementation into new products. LEMs are defined by three functional characteristics; they (1) are compliant, (2) are fabricated from planar materials, and (3) emerge from a flat initial state. Advantages, design challenges, and design tools are described for each of the functional characteristics. Opportunities for LEMs are discussed, namely disposable LEMs, novel arrays of LEMs, scaled LEMs, LEMs with surprising motion, shock absorbing LEMs, and deployable LEMs. Technology push product development processes were employed to select applications for LEMs. LEM technology was characterized. In a LEM workshop, eighteen industry professionals then helped identify over 200 potential applications for the technology. The applications were evaluated, and the most promising ideas that were identified for each LEM opportunity are described with graphics of possible product embodiments. Of the various product opportunities enabled by LEMs, deployable mechanisms – particularly in the credit card size – are among the most viable. The compactness and portability of credit-card-sized products create a strong motivation for their development. Expanding the capabilities of credit-card-sized mechanisms to include more sophisticated motions and a broader range of tasks may dramatically increase their market potential. A review of the current state-of-the-art in credit-card-sized mechanisms reveals two primary classes of mechanisms most commonly used in this form factor: rigid-body mechanisms and in-plane compliant mechanisms. The limitations of each and corresponding LEM advantages are described. Criteria for determining whether a product is a suitable candidate for using LEM technology to create or improve a credit-card-sized product are established. The advantages of LEMs in credit-card-sized products are illustrated through an example product: a compact lancing device that could be used as a main component for a highly portable epinephrine syringe.

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Fazio, Walter C. "Mechanical Properties and MEMS Applications of Carbon-Infiltrated Carbon Nanotube Forests." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3224.

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This work explores the use of carbon-infiltrated carbon nanotube (CI-CNT) forests as a material for fabricating compliant MEMS devices. The impacts of iron catalyst layer thickness and carbon infiltration time are examined. An iron layer of 7nm or 10nm with an infiltration time of 30 minutes produces CI-CNT best suited for compliant applications. Average maximum strains of 2% and 2.48% were observed for these parameters. The corresponding elastic moduli were 5.4 GPa and 4.1 GPa, respectively. A direct comparison of similar geometry suggested CI-CNT is 80% more flexible than single-crystal silicon. A torsional testing procedure provided an initial shear modulus of about 5 GPa for the 7-nm, 30-min CI-CNT. The strain and elastic modulus values were used to design numerous functional devices which were then fabricated in CI-CNT. A series of compliant cell restraint mechanisms were developed, assessed, and revised. A passive restraint with no moving parts was found to be both the most effective design and the easiest design to produce economically. A refined version of the passive restraint has been released commercially. Another series of designed devices successfully demonstrates the implementation of CI-CNT LEM designs.

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Le, Mellisa A. "Application of well log tomography to the Dundee and Rogers City Limestones, Michigan Basin, USA /." Available online. Click here, 2004. http://sunshine.lib.mtu.edu/ETD/THESIS/lema/mellisale%5Fthesis.pdf.

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Gómez, Calderón Jaime Alfonso. "Prototipo Virtual 2HMI Radio." Thesis, Universidad de las Américas Puebla, 2011. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/gomez_c_ja/.

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En la actualidad las empresas automotrices centran sus esfuerzos en la realización de productos enfocados en el rendimiento y confort y que es ofrecido a los usuarios. Debido a esto, es necesario incluir dispositivos que brinden al usuario la capacidad de configurar estos mismos, y por ende, permitan el control del funcionamiento del dispositivo basado en los requerimientos actuales del operador. Las interfaces Humano-Máquina (HMI) tienen como objetivo capturar como base las indicaciones recibidas por un operador humano el cual ingresa cierto tipo de parámetros al dispositivo y éste realiza acciones como respuestas a los deseos del usuario. Los radios de reproducción de audio implementados en los automóviles tienen como función principal de operación el entretenimiento de los pasajeros a bordo del carro, realizando la reproducción de varios formatos de audio en las bocinas propias del vehículo con la premisa principal de eliminar cualquier tipo de distracción al conductor generada por la operación manual del radio. Para lograr este objetivo, las empresas utilizan varias formas de evaluación del producto con el fin de perfeccionar los sistemas que harán parte de un automóvil teniendo en cuenta la opinión de los posibles usuarios.
(cont.) Una de estas técnicas de evaluación utiliza la simulación de prototipos físicos en aplicaciones virtuales, las cuales ofrecen al interesado características similares a las presentadas por los dispositivos en tiempo real. La simulación de autoestéreos permite conocer las respuestas de operación, entregadas por el radio, al realizar procedimientos de selección de modos de reproducción, búsqueda de estaciones de radio o canciones, reconocimiento y reproducción de dispositivos externos de almacenamiento de audio, etc. El uso de la herramienta RapidPLUS como interfaz de simulación permite elaborar aplicaciones compactas que en cierto modo recrean el entorno grafico de la aplicación y el funcionamiento básico del radio. Esta tesis plantea la elaboración de varias aplicaciones virtuales por medio de este software que simulen las operaciones y modos incluidos en el manual de funcionamiento del radio proporcionado por la empresa Volkswagen de México..

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Martínez, López Miguel Ángel. "Diseño y simulación de un sistema para detección de intrusos en redes de comunicaciones utilizando OMNET++." Thesis, Universidad de las Américas Puebla, 2010. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/martinez_l_ma/.

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La seguridad en las redes de comunicación se ha convertido en un factor de suma importancia debido a la presencia constante de intrusos en la red ya que son elementos que afectan la Calidad de Servicio y que se define como un parámetro para establecer el óptimo funcionamiento de la red a través de protocolos establecidos tal como el TCP (). Dicho protocolo está orientado a crear conexiones lógicas entre los nodos o equipos que integran a la red para comunicarse entre ellos a través del flujo de datos. Debido al crecimiento exponencial de usuarios en el Internet, éste se ha convertido en un medio importante e indispensable para la comunicación puesto que la mayoría de usuarios hacen uso de la red con el fin de efectuar sus operaciones. Esto obliga a los proveedores de Internet a emplear sistemas de seguridad que ofrezcan protección a los clientes para mantener la disponibilidad de los recursos y servicios en la red. El trabajo reportado en esta tesis tiene como objetivo realizar el diseño y simulación de un sistema de detección de intrusos para redes de comunicaciones utilizando OMNET++
(cont.) A través de simulaciones se detectarán los ataques o amenazas que afecten el desempeño de los elementos sobre la red diseñada. OMNET++ es una herramienta de simulación para redes de comunicaciones, el cual permite modelar protocolos, sistemas multiprocesadores o redes de telecomunicaciones. Para realizar el diseño del IDS () fueron considerados cinco ataques: DoS (), DDoS (), Ping of Death, XSS () y el MiTM (). Los ataques mencionados se emplearon por el desempeño que tienen en un ambiente real siendo amenazas que causan la denegación de servicios a clientes legítimos en una red. En la simulación se utilizaron estos ataques como las principales amenazas en la red diseñada afectando el ancho de banda de ciertos elementos, ya que es un recurso importante para la comunicación entre ellos. Posteriormente se obtuvieron resultados que muestran el daño provocado en las ?víctimas? por los ataques utilizados. Para la simulación inicialmente se emplearon como parámetros el ancho de banda de los elementos en la red, el cual fue de 250 Mbps () para los servidores y 80 Mbps para las PCs
(cont.) Estos valores fueron establecidos en función a la generación de tráfico de paquetes y ataques sobre la red, la cual es de 250 ms () para el tráfico de ataques y 100 ms para datos que no afectan como ataques a los elementos de la red considerados, tal como el correo eléctrónico o simples paquetes de texto. Finalmente los resultados obtenidos representan el desempeño del IDS diseñado ante los ataques utilizados. Durante su detección se presentaron los falsos negativos siendo tomados como parámetros para mostrar la eficiencia dicho sistema. En la ejecución de la simulación se programaron ciertos ataques que los IDS pueden detectar de manera que se pudiera observar el paso de algunos de estos ataques a través de los sistemas de seguridad y afectar a ciertas víctimas en el escenario simulado, representando así a los falsos negativos. En la simulación presentada en este trabajo de tesis, la eficiencia del sistema de seguridad compuesto por los IDS en la red se basó en el registro de los ataques que afectaron a ciertas víctimas y los que fueron detectados por el mismo sistema durante la simulación, siendo de un 93 % efectivo
(cont.) Cabe recordar que en la programación de la simulación este desempeño puede variar de acuerdo a la activación para la detección de los ataques en los IDS. .

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Rodríguez, Maltés Luis Raúl. "Análisis y predicción de cobertura de WiMAX a 3.3-3.4 GHZ para zonas rurales." Thesis, Universidad de las Américas Puebla, 2010. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/rodriguez_m_lr/.

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La red actual de SICOM que se utiliza para comunicarse entre diferentes municipios y dependencias del gobierno ya no alcanza a cubrir las necesidades actuales, por este motivo SICOM buscó financiamiento por parte de los Fondos Mixtos (FOMIX) del CONACyT y del gobierno del Estado, los cuales se otorgan a una universidad para resolver la demanda solicitada por SICOM y de esta manera mejorar el backbone el cual trabaja únicamente con OFDM, la cual es una buena técnica de modulación. La necesidad de crecimiento a corto plazo para cubrir nuevas aplicaciones relativas a las Tecnologías de Información, así como la necesidad del Gobierno del Estado de Puebla de brindar servicios a la población y comunidades con mayor rezago tecnológico obliga a fortalecer e incrementar la cobertura del 68% al 90% dentro del territorio del estado de Puebla. Para poder cumplir con esto SICOM decidió instalar radio-bases WiMAX. WiMAX es una tecnología de largo alcance que permite coberturas de hasta 40km. en espacio libre, y al trabajar con OFDM permite la compatibilidad necesaria para el backbone y no se tenga que sustituir la tecnología actual.
(cont.) Por esa razón se decidió utilizar WiMAX y no otro tipo de redes que a pesar de que presentarían las mismas o distintas ventajas, no permiten OFDM como base para la transmisión de datos. Como ya se mencionó, WiMAX permite una amplia cobertura, pero eso es pensando en modelos ideales, sin embargo para poder ver como se comportaría realmente la señal y la cobertura real que se dará a cada municipio o zona se necesita un software que realicen las simulaciones así como ver qué efectos tendría sobre la red. Debido a que los cálculos son muy complicados se necesitan diferentes programas o software que los realicen y los desplieguen, por lo que se buscaron programas que pudieran realizar tanto la simulación de la cobertura, que fue el Radio Mobile, así como ver la atenuación de la señal y los efectos que se tendría sobre la señal para puntos en específico, para esto se compró el software OPNET, con las licencias necesarias para poder crear las simulaciones. Todo esto se realizó con la finalidad de poder dar a SICOM los resultados de la investigación y dar recomendaciones sobre que se puede hacer para mejorar el backbone con la tecnología que se eligió y los posibles problemas que se podrían encontrar al realizar la instalación de los equipos y desplegarlos. .

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Brambila, Lozano Eduardo Felipe. "Sistema de Control Inalámbrico de Cámaras de Video Aplicado a la Detección de Incendios Forestales." Thesis, Universidad de las Américas Puebla, 2010. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/brambila_l_ef/.

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En la actualidad uno de los mayores problemas que afectan al mundo son los incendios forestales, debido que estos afectan a los ecosistemas, a la flora y a la fauna. Es por esto que se requieren crear nuevas formas de detección de incendios. Una forma de lograr una detección temprana de los incendios forestales es mediante el uso de tecnología. Desde el año 2006 el estado de Puebla ha implementado un sistema tecnológico de detección que consta de 16 cámaras conectadas de manera inalámbrica a una central desde la cual una persona realiza el monitoreo de las áreas boscosas en busca de un posible incendio. El movimiento de las cámaras es realizado por el operador del sistema mediante un joystick. Debido a que existe la posibilidad de un error humano se requiere que el sistema funcione de manera completamente automática, es decir, que el sistema mueva de manera automática las cámaras y realice la detección de un incendio. Debido a que la automatización de un sistema como este consta de varias partes, en la presente tesis se realizó una parte de este sistema. En esta tesis se logró implementar un sistema de comunicación inalámbrico y se realizó un programa el cual permite el control de las cámaras de video de la marca Pelco en dos modos: automático y manual.
(cont.) Se realizó un análisis de los sistemas tecnológicos de detección de incendios forestales que existen actualmente y se propuso un modelo automatizado para la detección de incendios en el estado de Puebla. El sistema de comunicación inalámbrico conecta a las cámaras con el sistema de procesamiento utilizando un par de antenas de la marca Canopy de Motorola. Las pruebas realizadas al sistema fueron en el modo manual y en el modo automático. En el modo manual se comprobaba de manera visual que los botones de la aplicación enviaran las tramas y las cámaras realizaran lo que se deseaba. En el modo automático se detectaba un incendio y el sistema le indicaba a las cámaras que se detuvieran y realizaran un acercamiento al evento. El programa para el control de las cámaras fue realizado en lenguaje C# utilizando la suite de Visual Studio 2008.

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Pozos, Barcelata Olivia. "Diseño e implementación de un cargador solar portatil." Thesis, Universidad de las Américas Puebla, 2010. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/pozos_b_o/.

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Este trabajo muestra el diseño de un dispositivo cargador de una batería de litio-ion, la cual almacena energía para después usarla para cargar un teléfono celular. Para llevar a cabo su función, este dispositivo utiliza una celda solar o el puerto USB de una computadora. De esta manera se podrá cargar el teléfono en circunstancias donde no se tiene acceso a línea eléctrica. Para el presente proyecto, se utiliza una celda solar comercial de 5.4 V a 300 mA y una batería de litio-ion de 3.7 volts a 860 mAh. El cargador solar cuenta con dos circuitos integrados: un regulador de voltaje para cargar la batería de litio-ion interna y un convertidor CD-CD para transferir la energía al teléfono celular. Se cargó la batería de litio- ion por medio de la celda solar en un tiempo de 1 hr 55 minutos y por medio del puerto USB de una computadora en 2 hrs 30 minutos. Se utilizó un teléfono celular Blackberry 8100 para realizar las pruebas.
(cont.) De la misma forma, se probó el cargador solar con otros modelos de teléfonos celulares y en algunos casos como en el iPhone 3GS solo detectaba un dispositivo pero no lograba realizar la carga. El primer capítulo justifica los principios teóricos que permiten fundamentar el diseño del cargador así como el funcionamiento de los elementos involucrados en el desarrollo del prototipo. En el segundo se describe el proceso de diseño del convertidor CD-CD así como la implementación física del mismo para comprobar su funcionamiento. En el tercer capítulo se justifica el diseño del cargador y muestra la implementación del cargador portátil inicial y un diseño mejorado. Y en el cuarto capítulo se detallan las pruebas experimentales del cargador y las correcciones realizadas en el diseño, donde se abordan los resultados del trabajo experimental.

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Mart��nez, P��rez Bethzabe Yaziriam. "Modulaci��n de coherencia ��ptica con dispositivos electro-��pticos con aplicaciones en detecci��n de campos el��ctricos." Thesis, Universidad de las Am��ricas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/martinez_p_by/.

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Angeles, Herrera Gretel. "Intercambio de Datos Multimedia en Redes Inter-vehiculares Utilizando Protocolos de Redes Fiables." Thesis, Universidad de las Américas Puebla, 2011. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/angeles_h_g/.

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La comunicación directa entre vehículos ha sido motivo de diversas investigaciones referentes a las redes móviles ad hoc que tienen la ventaja de ser una topología en constante evolución, sin embargo el mayor enfoque ha sido en la seguridad de los vehículos terrestres como los automóviles. A pesar de una extensa cantidad de investigaciones acerca de las comunicaciones inter-vehiculares, todavía no se ha llegado a un acuerdo acerca de los protocolos que se deben utilizar para los requerimientos de las aplicaciones. Las soluciones deben ser cuidadosamente seleccionadas para poder satisfacer las necesidades de los requerimientos como una comunicación fiable en tiempo real. Existen iniciativas internacionales para tener un estándar en comunicaciones inter vehiculares como el IEEE802.11p/WAVE/1609 y el estándar ISO TC204 WG16, sin embargo se sigue trabajando en ello. Estos sistemas de comunicaciones móviles tienen aún muchos problemas que enfrentar debido a los difíciles escenarios de operación como lo son las condiciones de propagación, además de la necesidad de una comunicación fiable y con bajo retardo. Debido a esto los protocolos de comunicación que se diseñen para estas aplicaciones, deben tener altos niveles de fiabilidad, robustez y flexibilidad. En este trabajo se presenta una descripción general de los sistemas de comunicación vehicular, las características y sus aplicaciones. Existen diversidad de protocolos que se pretenden implementar para las comunicaciones inter-vehiculares, sin embargo aún no existe uno en específico que cumpla todas las características que una red vehicular requiere para poder funcionar adecuadamente, especialmente con respecto a la alta movilidad de los nodos. Algunos protocolos son mencionados y clasificados según su alcance, modo de transmisión, planificación, etc. sin embargo, únicamente los protocolos AODV (Ad-Hoc On-Demand Distance Vector-Routing) y OLSR (Optimized Link State Routing) serán estudiados con mayor profundidad mencionando cómo funcionan y de igual forma midiendo la eficiencia y rendimiento de cada uno por medio de estudios de comparación realizados por autores en investigaciones y trabajos previos.

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Matus, Hernández Luciano. "Evaluación de un sistema fotovoltaico." Thesis, Universidad de las Américas Puebla, 2012. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/matus_h_l/.

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Es bien sabido que la mayor parte de la generación de energía en nuestro país es mediante quema de combustibles, lo cual indica que en un futuro no muy lejano, tendremos serios problemas para dar soporte a la gran cantidad de energía que utilizamos a nivel país y a nivel mundial. Es por ello que es necesario pensar, implementar y mejorar las alternativas de generación energética utilizando fuentes alternativas, ilimitadas y menos desgastantes para el medio ambiente. Actualmente sabemos que existen muchos países utilizando diferentes fuentes energéticas y esto se ha ido expandiendo para mejorar la calidad de vida y dar solución al problema de la quema de combustibles como fuente generadora. Pensando en la problemática planteada se diseño este proyecto para el diseño, evaluación, beneficios y la utilización de sistemas fotovoltaicos como fuente generadora de energía. El trabajo está distribuido de la siguiente manera. En el primer capítulo se explica la problemática de las fuentes de energía, por lo cual es realizado este proyecto, además de los alcances y limitaciones. En el segundo capítulo incluimos los antecedentes, las definiciones y descripciones que se utilizaron en el proyecto, para facilitar al lector el claro entendimiento de los conceptos. En los siguientes dos capítulos se muestra la propuesta que se utilizo para la implementación de sistemas fotovoltaicos, los componentes de dicho sistema y que herramientas nos facilitaron la comprensión. Así como la selección de componentes, tipo de conexión, lugares, temperaturas, etc. En los capítulos 5 y 6 se presenta los resultados, propuestas que se pueden manejar y la explicación grafica de dichos resultados, así como las conclusiones a las que se llego en la realización del proyecto. Finalmente dejamos un capitulo de trabajo a futuro para la continuación o ampliación del proyecto de sistemas fotovoltaicos.

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Cuautle, Arenas José Luis. "Diseño de redes eléctricas automotrices." Thesis, Universidad de las Américas Puebla, 2014. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/cuautle_a_jl/.

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En todos los sistemas eléctricos del auto, se tiene la presencia de componentes electrónicos los cuales reciben señales eléctricas y que después distribuyen nuevas señales procesadas y que son la entrada para otros componentes eléctricos. Inclusive dentro del auto tenemos redes de área local en las que estas unidades de control se comunican a través de un BUS intercambiando información para optimizar el funcionamiento de un sistema. Por lo anterior, uno de los conceptos fundamentales de la electrónica del auto es la transmisión de señales eléctricas. Todos los componentes eléctricos necesitan de esta transmisión para poder funcionar. El medio a través del cual se van a transmitir estas señales es la red eléctrica de abordo. La red eléctrica de abordo transmite todas las señales eléctricas en el auto: Señales de alimentación y de comunicación y/o datos, necesarias para que todas las unidades de control y elementos eléctricos del auto funcionen, por lo tanto, conecta eléctricamente a todos y cada uno de los componentes eléctricos del auto. Las redes eléctricas tienen dos tipos de características: Características eléctricas y características mecánicas. Las características eléctricas tienen que ver en si con las conexiones de los componentes eléctricos del auto. Las características mecánicas tienen que ver con la manera de asegurar la fijación y montaje de la red y de los componentes eléctricos a la carrocería del auto. El resultado del diseño de una red eléctrica y de sus componentes, es toda la información técnica que describe completamente la red de un auto en particular. Esta información técnica queda reflejada en un dibujo de la red eléctrica (datos 2D) y en unos datos 3D. Una vez que se ha realizado el diseño de una red eléctrica o de un soporte (para la fijación de la misma o de un componente eléctrico), se tiene la información técnica necesaria (información 2D y 3D), para que un proveedor especializado pueda producir piezas para la serie. Cuando el proveedor tiene los medios definitivos para producir estas piezas, tiene que entregar muestras al área de diseño de redes eléctricas para que se puedan liberar. La liberación de estas piezas, se da a través de someterlas a una serie de pruebas que al final aseguren que son aptas para su montaje en un auto. Las pruebas que se realizan son de dos tipos: Mecánicas y eléctricas. Las pruebas eléctricas tienen la finalidad de asegurar el concepto eléctrico de las redes eléctricas de abordo y a través de estas pruebas, es posible determinar las corrientes de funcionamiento y las caídas de voltaje reales dentro de la red y sirven para asegurar que el dimensionamiento de los fusibles y la sección transversal de los cables es la correcta. Las pruebas mecánicas tienen la finalidad de asegurar el correcto montaje de la red en la carrocería del auto, así como asegurar que durante toda su vida la red no tenga ningún daño. El aseguramiento de la función de una red eléctrica de abordo se basa en un proceso de diseño y de pruebas, robusto y preciso, en el cual están involucradas desde el área de diseño hasta las área de compras, logística, producción, calidad e inclusive el proveedor de serie. Este proceso de diseño y pruebas está basado en su mayor parte en sistemas digitales que proporcionan seguridad, transparencia y control de costos, plazos y complejidad.

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Carballo, Vega Edgar Raúl. "LTE Vs. Wimax móvil Vs. HSPA (HSUPA, HSDPA) como tecnologías de redes MAN." Thesis, Universidad de las Américas Puebla, 2013. http://catarina.udlap.mx/u_dl_a/tales/documentos/lem/carballo_v_er/.

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En este proyecto final se describe, se analiza y se compara la capa física de LTE (Long Term Evolution) y WIMAX móvil (Worldwide Interoperability for Microwave Access), para determinar la mejor tecnología en la implementación de una red de área metropolitana. Se tienen dos estándares tecnológicos de dos grandes desarrolladores de tecnología de telecomunicaciones. Este proyecto final se concentra en la capa física de estos estándares, la cual se encarga de asegurarse que la señal sea transportada exitosamente de un dispositivo a otro. Se lleva a cabo la codificación, modulación y sincronización de señales. El título del proyecto final, incluye HSPA (High Speed Packet Acces), con sus propios estándares en su enlace de subida y su enlace de bajada, HSDPA (High Speed Downlink Packet Acces) y HSUPA (High Speed Uplink Packet Acces) respectivamente como tecnología de red de área metropolitana, la tecnología HSPA fue estandarizada por 3GPP (3rd Generation Partnership Project), creada como complemento de WCDMA (Wideband Code Division Multiple Access) para mejorar la velocidad de datos y así poder obtener el máximo de beneficios en GSM (Global System for Mobile Communications) para la tercera generación de telecomunicaciones. En la actualidad existe como propuesta la nueva versión de HSPA llamada HSPA+ (evolución de HSPA), la cual complementa a LTE para la transición de la red tercera generación a cuarta generación; por lo que sólo se harámención de esta tecnología como trabajo futuro.

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Ollinger, Christoph German Josef. "A waveguide-based lens-less x-ray microscope." Doctoral thesis, [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/ollinger.

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Miron, Georgeta Elena. "Les legs de Beckett dans la dramaturgie française contemporaine." Grenoble, 2010. http://www.theses.fr/2010GRENL005.

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Le théâtre des années 50, appelé tardivement "théâtre de l'absurde" par Martin Esslin, naît comme le reflet naturel d'un état d'esprit propre à l'époque et non pas à partir d'un programme préétabli par les artistes/écrivains. Dans ce contexte particulier, Samuel Beckett occupe une place essentielle, aux côtés d'Eugène Ionesco (auteur de Notes et contre-notes, un des seuls ouvrages consacrés à une conceptualisation des techniques dramaturgiques des années 50). Notre travail tente de suivre les diverses façons dont la dramaturgie française contemporaine (Louis Calaferte, Patrick Kermann, Jean-Luc Lagarce, Marie Redonnet et Matéi Visniec) a su capter, incorporer et faire renaître la spécificité de l'œuvre théâtrale de Beckett. Passer en revue les univers dramaturgiques des auteurs étudiés était une approche nécessaire, notamment parce que le corpus comprend des noms peu connus donc des auteurs peu analysés actuellement. Dans le cadre de ce mémoire, nous montrons qu'à travers les éléments paraverbaux les auteurs contemporains suivent le modèle de Beckett et font parfois entendre leur voix sous la couverture d'un narrateur ou d'un des personnages. Les thématiques telles que la guerre, la politique, l'isolement, l'enfermement, la solitude sont autant de liens qui se tissent entre les générations d'écrivains et témoignent de façon convaincante de l'existence des legs de Beckett dans le théâtre français contemporain. A travers le langage, ce rapport intergénérationnel est à nouveau mis en avant. La parole est épuisée, le mot balbutie, la phrase cassée est souvent reprise pour ensuite être abandonnée à une mémoire difficilement perceptible. Le personnage est ensuite décliné dans ses rapports avec soi-même, avec, et contre l'altérité. La question des procédés de filiation est posée à l'aboutissement de nos recherches. En l'absence de quelques instruments indispensables pour l'analyse des rapports textuels entre certaines pièces, nous proposons des solutions terminologiques et conceptuelles, en accord avec l'évolution du théâtre contemporain.

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Sanyal, Anuradha. "Large eddy simulation of syngas-air diffusion flames with artificial neural networks based chemical kinetics." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42785.

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In the present study syngas-air diffusion flames are simulated using LES with artificial neural network (ANN) based chemical kinetics modeling and the results are compared with previous direct numerical simulation (DNS) study, which exhibits significant extinction-reignition and forms a challenging problem for ANN. The objective is to obtain speed-up in chemistry computation while still having the accuracy of stiff ODE solver. The ANN methodology is used in two ways: 1) to compute the instantaneous source term in the linear eddy mixing (LEM) subgrid combustion model used within LES framework, i.e., laminar-ANN used within LEMLES framework (LANN-LEMLES), and 2) to compute the filtered source terms directly within the LES framework, i.e., turbulent-ANN used within LES (TANN-LES), which further dicreases the computational speed. A thermo-chemical database is generated from a standalone one-dimensional LEM simulation and used to train the LANN for species source terms on grid-size of Kolmogorov scale. To train the TANN coefficients the thermo-chemical database from the standalone LEM simulation is filtered over the LES grid-size and then used for training. To evaluate the performance of the TANN methodology, the low Re test case is simulated with direct integration for chemical kinetics modeling in LEM subgrid combustion model within the LES framework (DI-LEMLES), LANN-LEMLES andTANN-LES. The TANN is generated for a low range of Ret in order to simulate the specific test case. The conditional statistics and pdfs of key scalars and the temporal evolution of the temperature and scalar dissipation rates are compared with the data extracted from DNS. Results show that the TANN-LES methodology can capture the extinction-reignition physics with reasonable accuracy compared to the DNS. Another TANN is generated for a high range of Ret expected to simulate test cases with different Re and a range of grid resolutions. The flame structure and the scalar dissipation rate statistics are analyzed to investigate success of the same TANN in simulating a range of test cases. Results show that the TANN-LES using TANN generated fora large range of Ret is capable of capturing the extinction-reignition physics with a very little loss of accuracy compared to the TANN-LES using TANN generated for the specific test case. The speed-up obtained by TANN-LES is significant compared to DI-LEMLES and LANN-LEMLES.

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Yan, Yufeng. "Photographic Fisheye Lens Design for 35mm Format Cameras." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613395.

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Fisheye lenses refer to ultra-wide angle lenses that have field of view equal or larger than 180 degrees. Such lenses introduce large amount of barrel distortion to capture at least the entire hemisphere in front of the lens. Fisheye lenses were initially designed for scientific use, such as cloud recording and angle measuring, and were widely used for commercial purposes later. The development of photographic fisheye lenses started in 1960s. However, the lack of detailed references on photographic fisheye lens design makes such design challenging. This thesis provides detailed introduction of photographic fisheye lens design for 35mm format DSLR cameras. A discussion on the history of fisheye lenses is provided to describe the development of fisheye lenses. The tangential and sagittal magnifications are mathematically derived for each fisheye lens projection mapping method to show their differences. The special properties and design issues of photographic fisheye lenses are described in detail. Along with each design issue, some solutions suggested by the author are also provided. The performance of the current diagonal fisheye lenses for 35mm DSLR cameras are evaluated in detail. Then a new diagonal fisheye lens designed by the author is presented and compared with the current diagonal fisheye lenses on the market. Finally, a zoom fisheye lens designed for 35mm DSLR cameras is presented and discussed.

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Huang, Yi-Shiang. "Intraocular lenses with surfaces functionalized by biomolecules in relation with lens epithelial cell adhesion." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0464/document.

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L’Opacification Capsulaire Postérieure (OCP) est la fibrose de la capsule développée sur la lentille intraoculaire implantée (LIO) suite à la dé-différenciation de cellules épithéliales cristalliniennes (LECs) subissant une transition épithélio-mésenchymateuse (EMT). La littérature a montré que l'incidence de l’OCP est multifactorielle, dont l'âge ou la maladie du patient, la technique de chirurgie, le design et le matériau de la LIO. La comparaison des LIOs en acryliques hydrophiles et hydrophobes montre que les premières ont une OCP plus sévère, médiée par la transition EMT. En outre, il est également démontré que l'adhérence des LECs est favorisée sur des matériaux hydrophobes par rapport à ceux hydrophiles. Une stratégie biomimétique destinée à promouvoir l’adhérence des LECs sans dé-différenciation en vue de réduire le risque de développement de l’OCP est proposée. Dans cette étude, les peptides RGD, ainsi que les méthodes de greffage et de quantification sur un polymère acrylique hydrophile ont été étudiés. La surface fonctionnalisée des LIOs favorisant l'adhérence des LECs via les récepteurs de type intégrine peut être utilisée pour reconstituer la structure capsule-LEC-LIO en sandwich, ce qui est considéré dans la littérature comme un moyen de limiter la formation de l‘OCP. Les résultats montrent que le biomatériau innovant améliore l'adhérence des LEC, et présente également les propriétés optiques (transmission de la lumière , banc optique) similaires et mécaniques (force haptique de compression, force d'injection de la LIO) comparables à la matière de départ. En outre, par rapport au matériau hydrophobe IOL, ce biomatériau bioactif présente des capacités similaires vis à vis de l’adhérence des LECs, le maintien de la morphologie, et l'expression de biomarqueurs de l’EMT. Les essais in vitro suggèrent que ce biomatériau a le potentiel de réduire certains facteurs de risque de développement de l’OCP
Posterior Capsular Opacification (PCO) is the capsule fibrosis developed onto the implanted IntraOcular Lens (IOL) by the de-differentiation of Lens Epithelial Cells (LEC) undergoing Epithelial-Mesenchymal Transition (EMT). Literature has shown that the incidence of PCO is multifactorial including patient’s age or disease, surgical technique, and IOL design and material. Reports comparing hydrophilic and hydrophobic acrylic IOLs show the former has more severe PCO after EMT transition. Additionally, the LEC adhesion is favored onto the hydrophobic materials compared to the hydrophilic ones. A biomimetic strategy to promote LEC adhesion without de-differentiation to reduce PCO development risk is proposed. RGD peptides, as well as their grafting and quantification methods on a hydrophilic acrylic polymer were investigated. The surface functionalized IOL promoting LEC adhesion via integrin receptors can be used to reconstitute the capsule-LEC-IOL sandwich structure, which is considered to prevent PCO formation in literature. The results show the innovative biomaterial improves LEC adhesion, and also exhibits similar optical (light transmittance, optical bench) and mechanical (haptic compression force, IOL injection force) properties comparing to the starting material. In addition, comparing to the hydrophobic IOL material, this bioactive biomaterial exhibits similar abilities in LEC adhesion, morphology maintenance, and EMT biomarker expression. The in vitro assays suggest this biomaterial has the potential to reduce some risk factors of PCO development

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Fontaine, Marion. "Les « Gueules Noires » et leur club : sport, sociabilités et politique à « Lens les Mines » (1934-1956)." Paris, EHESS, 2006. http://www.theses.fr/2006EHES0145.

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L’enjeu est d’analyser les liens tissés entre un club de football, le Racing Club de Lens (RCL), une ville, Lens, et un groupe social, celui des mineurs. Cette analyse englobe vingt-deux années de l’histoire du club, de son accession au statut professionnel à son cinquantenaire. Elle vise à comprendre comment le RCL a été progressivement érigé en lieu consensuel et en support d’identiﬁcation pour les «Gueules Noires» de Lens, durant une période marquée par la conquête du football par la communauté minière, mais aussi par la crise protéiforme que traverse cette communauté. L’histoire du club s’insère, de fait, dans le mouvement des sociabilités sportives lensoises et dans le rapport que celles-ci entretiennent avec les différentes institutions qui régissent la ville: compagnie minière, municipalité, syndicat, etc. Cette analyse sportive s’articule donc à une lecture politique et à une réﬂexion sur la façon dont se fait et se défait un monde ouvrier
We try to understand how the links between a sport club The Racing Club de Lens, a town, Lens, and a social group, the coal miners, were forged, The following analysis includes twenty-two years of the history of RCL, from its professionalization to its 50"‘ anniversary. We explain how the club become the place of a peculiar consensus and how it can corne to symbolise the community of the coal miners, The period is characterised by the increasing involvement in football by the mining community and by the great crisis of this community, The present work aims therefore at understanding the RCL in the broader context of the sports associations and the institutions which shape Lens : mining company, local authorities and trade unions. The evolutions of the sports associations allows a new reading of the mining world, namely that of the political aspects of this world. The sporting gaine can help us understand how a working-class community has successively been shaped and reshaped

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Yuan, Sheng. "Aberrations of Anamorphic Optical Systems." Diss., The University of Arizona, 2008. http://hdl.handle.net/10150/195267.

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A detailed study of the aberrations of anamorphic optical systems is presented. This study has been developed with a theoretical structure similar to that of rotationally symmetric optical systems (RSOS) and can be considered a generalization.A general method of deriving the monochromatic primary aberration coefficient expressions for any anamorphic system types with double plane symmetry has been provided.The complete monochromatic primary aberration coefficient expressions for cylindrical anamorphic systems, toroidal anamorphic systems and general anamorphic systems with aspheric departure have been presented, in a form similar to the Seidel aberrations of RSOS.Some anamorphic image system design examples are provided that illustrate the use and value of the theory developed.

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Ramos, Paulo Roberto Barbosa. "O controle concentrado de constitucionalidade das leis na ordem jurídica brasileira pós-88: para uma análise de sua filosofia e de suas dimensões jurídico-políticas." reponame:Repositório Institucional da UFSC, 1997. https://repositorio.ufsc.br/handle/123456789/106448.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciencias Juridicas
Made available in DSpace on 2013-12-05T20:33:27Z (GMT). No. of bitstreams: 0 Previous issue date: 1997Bitstream added on 2016-01-08T22:09:06Z : No. of bitstreams: 1 108686.pdf: 5475162 bytes, checksum: 2bbe174b258f1aeb68a8e74a1470e39f (MD5)
Análise da evolução da idéia de controle de constitucionalidade das leis no Ocidente e de sua influência sobre a história constitucional brasileira. Estuda o desenvolvimento do controle de constitucionalidade das leis no Brasil, com o objetivo de compreender a filosofia e as dimensões jurídico-políticas do controle concentrado de constitucionalidade das leis adotado na ordem jurídica brasileira pós-88.

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Wilson, Cynthia Nicole. "A Fully Customizable Anatomically Correct Model of the Crystalline Lens." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20130.

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The human eye is a complex optical system comprised of many components. The crystalline lens, an optical component with a gradient index (GRIN), is perhaps the least understood as it is situated inside the eye and as a result is difficult to characterize. Its complex nonlinear structure is not easily measured and consequently not easily modeled. Presently several models of the GRIN structure exist describing the average performance of crystalline lenses. These models, however, do not accurately describe the performance of crystalline lenses on an individual basis and a more accurate individual eye model based on anatomical parameters is needed. This thesis proposes an anatomically correct, individually customizable crystalline lens model. This is an important tool and is needed both for research on the optical properties of human eyes and to diagnose and plan the treatment of optically based visual problems, such as refractive surgery planning. The lens model consisted of an interior GRIN with a constant refractive index core. The anterior and posterior surface was described by conic sections. To realize this eye model, the optical and biometric properties of mammalian lenses were measured and the correlation relationships between these measurements were used to simplify the model down to one fitting parameter which controls the shape of the GRIN. Using this data, an anatomically correct individualizable model of the lens was successfully realized with varying parameters unique to each lens. Using this customizable lens model, customizable human eye models based on measurements of the entire human eye can be realized.

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Bowers, Daniel S. ""Let's stick together" : social identity, music fans, and group membership." Thesis, University of South Wales, 2016. https://pure.southwales.ac.uk/en/studentthesis/lets-stick-together(0efbe4e9-c20c-44e1-93a2-f85ff7702a23).html.

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Social identity theory (SIT) suggests that the groups to which an individual belongs, to a large degree, define their identity. Previous research has demonstrated that music fanship is a particularly effective group membership for the construction and communication of an individual's identity (e.g. Rentfrow & Gosling, 2003) and that music preferences can guide how we perceive and act towards others (e.g. Lonsdale & North, 2009). However, there has not been a great deal of research examining the differences between the fans of different styles of music and also how and why the importance of music fanship changes across the lifespan. This thesis examines the differences between the fans of different styles of music on key indices of social identity. It also examines whether there are cross sectional age differences between music fans in terms of these indices. The current body of work was designed so that aspects of the findings could be triangulated between studies to increase their reliability and validity. Six studies, using a variety of methodologies, have been conducted to investigate these questions. Study 1 was questionnaire based and investigated four key areas of music fanship (1) perceived commitment, (2) behavioural commitment, (3) music based judgements of others & (4) music group joining processes. Studies 2 and 3 were quasi experimental in nature and made use of a novel visual analogue scale to assess differences between fans of different musical styles on their in-group identification and other indices of social identity and to test elements of contemporary conceptualisations of identification. Study 4 was a card sorting task which examined the relative importance of music to fans' identities. Study 5 was an adjective selection task where fans were asked to choose words that described the members of both their musical in-group and selected out-groups to investigate key social identity processes. Study 6 was a large scale qualitative study where fans of different musical styles and ages were asked to talk about their experiences of being a music fan across the lifecourse. Study 1 showed that there were key differences between fans of different musical styles and ages in terms of the four areas investigated. Studies 2, 3 and 4 demonstrated that although people saw their music fanship as being relatively important to their overall identity, that there did not appear to be significant differences between fans of different ages or of different types in this regard. These studies also showed support for elements of the Leach at al. (2008) model of identification as well as Postmes et al.'s (2013) single dimension of identification. Study 5 indicated that the self-definition profiles of different music fan groups were indeed different from one another and that fans were more positive than negative about the members of their in-group. It also demonstrated that an individual's own group membership had an impact on how they subsequently described the members of opposing groups. A thematic analysis of the interviews and focus groups in Study 6 found that three superordinate themes emerged. These were (1) group joining & becoming a fan, (2) social identity processes amongst music fans & (3) music fanship changes across the lifespan. These findings show clear differences between the fans of different musical styles in aspects of group joining processes, subsequent social identity processes with which they engage and how much they identify with their in-group. It also demonstrates cross sectional differences between fans of different ages for these processes. These findings have implications for future research on elective group membership and social identity processes.

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Valley, Pouria. "FLAT LIQUID CRYSTAL DIFFRACTIVE LENSES WITH VARIABLE FOCUS AND MAGNIFICATION." Diss., The University of Arizona, 2010. http://hdl.handle.net/10150/145737.

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Non-mechanical variable lenses are important for creating compact imaging devices. Various methods employing dielectrically actuated lenses, membrane lenses, and liquid crystal lenses were previously proposed [1-4]. In This dissertation the design, fabrication, and characterization of innovative flat tunable-focus liquid crystal diffractive lenses (LCDL) are presented. LCDL employ binary Fresnel zone electrodes fabricated on Indium-Tin-Oxide using conventional micro-photolithography. The light phase can be adjusted by varying the effective refractive index of a nematic liquid crystal sandwiched between the electrodes and a reference substrate. Using a proper voltage distribution across various electrodes the focal length can be changed between several discrete values. Electrodes are shunted such that the correct phase retardation step sequence is achieved. If the number of 2πzone boundaries is increased by a factor of m the focal length is changed from f to f/m based on the digitized Fresnel zone equation: f = rm²/2mλ, where r(m) is mth zone radius, and λ is the wavelength. The chromatic aberration of the diffractive lens is addressed and corrected by adding a variable fluidic lens. These LCDL operate at very low voltage levels (±2.5V ac input), exhibit fast switching times (20-150 ms), can have large apertures (>10 mm), and small form factor, and are robust and insensitive to vibrations, gravity, and capillary effects that limit membrane and dielectrically actuated lenses. Several tests were performed on the LCDL including diffraction efficiency measurement, switching dynamics, and hybrid imaging with a refractive lens. Negative focal lengths are achieved by adjusting the voltages across electrodes. Using these lenses in combination, magnification can be changed and zoom lenses can be formed. These characteristics make LCDL a good candidate for a variety of applications including auto-focus and zoom lenses in compact imaging devices such as camera phones. A business plan centered on this technology was developed as part of the requirements for the minor in entrepreneurship from the Eller College of Management. An industrial analysis is presented in this study that involves product development, marketing, and financial analyses (Appendix I).

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Moore, Lori Briggs. "Defining Ray Sets for the Analysis of Lenslet-Based Optical Systems Including Plenoptic Cameras and Shack-Hartmann Wavefront Sensors." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/332894.

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Plenoptic cameras and Shack-Hartmann wavefront sensors are lenslet-based optical systems that do not form a conventional image. The addition of a lens array into these systems allows for the aberrations generated by the combination of the object and the optical components located prior to the lens array to be measured or corrected with post-processing. This dissertation provides a ray selection method to determine the rays that pass through each lenslet in a lenslet-based system. This first-order, ray trace method is developed for any lenslet-based system with a well-defined fore optic, where in this dissertation the fore optic is all of the optical components located prior to the lens array. For example, in a plenoptic camera the fore optic is a standard camera lens. Because a lens array at any location after the exit pupil of the fore optic is considered in this analysis, it is applicable to both plenoptic cameras and Shack-Hartmann wavefront sensors. Only a generic, unaberrated fore optic is considered, but this dissertation establishes a framework for considering the effect of an aberrated fore optic in lenslet-based systems. The rays from the fore optic that pass through a lenslet placed at any location after the fore optic are determined. This collection of rays is reduced to three rays that describe the entire lenslet ray set. The lenslet ray set is determined at the object, image, and pupil planes of the fore optic. The consideration of the apertures that define the lenslet ray set for an on-axis lenslet leads to three classes of lenslet-based systems. Vignetting of the lenslet rays is considered for off-axis lenslets. Finally, the lenslet ray set is normalized into terms similar to the field and aperture vector used to describe the aberrated wavefront of the fore optic. The analysis in this dissertation is complementary to other first-order models that have been developed for a specific plenoptic camera layout or Shack-Hartmann wavefront sensor application. This general analysis determines the location where the rays of each lenslet pass through the fore optic establishing a framework to consider the effect of an aberrated fore optic in a future analysis.

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Sasian, Jose, and Yufeng Yan. "Miniature camera lens design with a freeform surface." SPIE-INT SOC OPTICAL ENGINEERING, 2017. http://hdl.handle.net/10150/627187.

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We present a miniature camera lens design method that uses a freeform surface based on the pedal curve to the ellipse in polynomial form. Two designs are presented and their benefits of optical performance and tolerance sensitivity are compared to designs with conventional aspheric surfaces. We also reverse a freeform design using even aspherical surfaces to show that the optimization solution of a freeform design cannot be reproduced by even aspherical surfaces.

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NASCIMENTO, Jadiel da Silva. "Dispositivo para medição e controle da pressão do balonete das proteses traqueais." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18945.

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O uso de ventilação artificial é indicado para indivíduos que apresentem, insuficiência ou falência respiratória, traumatismo crânio encefálico ou pacientes politraumatizados. As unidades de terapia intensiva (UTIs) são ambientes destinados ao atendimento de pacientes graves, com potencial risco de morte, que necessitam de atendimento ininterrupto, caracterizadas, muitas vezes, como um ambiente relacionado ao sofrimento e a morte. Sabe-se que nessas unidades é comum encontrar pacientes que necessitam de suporte ventilatório mecânico invasivo através de prótese traqueal. A pesquisa deve como objetivo desenvolver um equipamento específico para aferir e corrigir a pressão do balonete do tubo endotraqueal ou cânula de traqueostomia, e verificar o nível de conhecimento dos profissionais de saúde referente a pressão do balonete externo do tubo ou cânula traqueal. Trata-se de um estudo experimental, realizado no ano de 2015 no laboratório de instrumentação biomédica do Departamento de Engenharia Biomédica da Universidade Federal de Pernambuco (UFPE). O passo inicial para o desenvolvimento do equipamento foi a escolha do sensor de pressão de baixa intensidade, cuja a função primordial do sensor de pressão é transformar uma grandeza fisiológica (pressão) em uma grandeza elétrica (tensão). O equipamento desenvolvido é capaz de monitorar a pressão do cuff, em tempo real e de forma continua. O sistema de alarme sonoro e visual com três LEDs, cada uma com finalidades diferentes, sendo a LED verde responsável em informar que os valores estão dentro dos normais, a LED amarela indica que o valor da pressão se encontra fora dos limites máximo e mínimo estabelecidos como referência e a LED vermelha indicando pressão nula do cuff. O dispositivo criado nesta pesquisa pode monitorar de forma continua a pressão do cuff, e em tempo real sinalizar aos profissionais das UTIs que os valores pressóricos se encontram fora dos limites estabelecidos pelo profissional de saúde. A maioria dos profissionais das duas UTI utilizam técnica de mensuração da pressão do cuff de forma subjetiva com a palpação digital, ao mesmo tempo que realizam o ajuste de forma errada com a utilização da seringa, sem ter a precisão de ter corrigido a pressão para os valores correto
The use of artificial ventilation is indicated for individuals who have, failure or respiratory failure, cranial trauma or polytrauma patients. Intensive care units (ICUs) are environments used in the treatment of critically ill patients with potentially lifethreatening, which require uninterrupted service, characterized often as a related suffering and death environment. It is known that these units is common to find patients requiring invasive mechanical ventilation through tracheal prosthesis. Research should aim to develop specific equipment to measure and correct the pressure of the cuff of the endotracheal tube or tracheostomy tube, and check the level of knowledge of health professionals concerning the external pressure cuff tube or tracheal cannula. This is an experimental study carried out in 2015 in biomedical instrumentation laboratory of the Department of Biomedical Engineering at the Federal University of Pernambuco (UFPE). The initial step in the development of the equipment was the choice of low-level pressure sensor, whose primary function of the pressure sensor is to turn a physiological variable (pressure) into an electrical magnitude (voltage). The equipment developed is able to monitor the cuff pressure in real time and continuously. The audible and visual alarm system with three LEDs, each with different purposes, and the green LED charge to report that the values are within normal, the yellow LED indicates that the pressure value is outside the maximum and minimum limits as a reference and the red LED indicates zero pressure cuff. The device created in this research can monitor continuously the pressure of the cuff, and real-time signal to the ICU professionals that blood pressure values are outside the limits set by health professional. Most practitioners of the two ICUs use cuff pressure measurement technique subjectively by digital palpation while performing adjustment in the wrong way with the use of the syringe without having to precision have fixed pressure for correct values.

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Nuytens, Williams. "Essai de sociologie des supporters du football : une enquête à Lens et à Lille." Lille 1, 2000. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2000/50377-2000-15.pdf.

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Duda, Radek. "Analýza ultratenkých vrstev metodami SIMS a TOF-LEIS." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228253.

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Kumar, Bharat. "The Mechanobiology of the Crystalline Lens." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587649113548924.

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Gilligan, Therese M. "Behind the lens : sensorimotor and cognitive after-effects of prism adaptation." Thesis, Bangor University, 2017. https://research.bangor.ac.uk/portal/en/theses/behind-the-lens(fd8b122f-8110-4aa8-ab21-105d476fe0bd).html.

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Over a century of research into prism adaptation (PA) has provided many insights into general sensorimotor functions including plasticity and the role of prediction. More recently, the therapeutic value of PA for conditions relating to right hemisphere dysfunction such as hemispatial neglect, and to body schema related conditions such as complex region pain syndrome, have generated a wealth of new knowledge – and more questions (Chapter 1). This thesis examines a cross-section of PA effects: sensorimotor adaptation in healthy participants and cognitive after-effects in a neurological population as well as a group of participants with a virtual lesion. Chapter 2 reports that PA does not induce an after-effect shift in a visual straightahead judgment task, while it does induce after-effects in other tasks which are attributable to a change in state estimates of eye position in the orbit. The results suggest that PA prompts complex changes within ocular proprioception and indicate that the assumption of linear additivity of PA sensorimotor after-effects is a concept requiring re-examination. An increase in priming following both right-shifting and left-shifting PA in patients with a left hemisphere lesion provides a first demonstration of the rehabilitative potential of PA for left hemisphere dysfunctions. Intriguingly, this result also widens the possible candidate mechanisms through which PA facilitates cognitive after-effects (Chapter 3). Finally, this thesis explores the potential influence of the cerebellum in the cognitive after-effects of PA (Chapter 4). It reports, for the first time, that neurodisruption of the right cerebellar hemisphere increases and left cerebellar stimulation decreases word association priming. The results indicate that the two cerebellar hemispheres conjointly schedule the facilitation and inhibition of associative priming. Taken together, the novel findings reported here suggest that previous theoretical stand-points need to be revised and provide a new framework for understanding the relationship between sensorimotor adaptation, cerebellar function and hemispheric interactions in human cognition.

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Andrulaitytė, Giedrė. "Įstrižojo astigmatizmo kompiuterinis modeliavimas sferiniuose ir asferiniuose lęšiuose." Bachelor's thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140716_105157-99873.

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Bakalauro darbą „Įstrižojo astigmatizmo kompiuterinis modeliavimas sferiniuose ir asferiniuose lęšiuose“ sudaro įvadas, 5 dėstymo skyriai, išvados ir priedai. Darbe pateikiami 50 paveikslai ir 2 lentelės, cituojami 16 literatūros šaltinių. Darbo apimtis 66 lapai. Darbe apibendrinta literatūra apie lęšių aberacijas, jų įtaką regėjimo kokybei, bei minimalizavimą asferiniais lęšiais. Taip pat pateikiami matematiniai sferinių ir asferinių lęšių modeliai, bei įstrižojo astigmatizmo analizė šiuose lęšiuose. Įvade iškeliami darbo tikslai ir uždaviniai. Pirmajame skyriuje pateikta teorinė medžiaga apie lęšių aberacijas, antrajame – apie sferinius ir asferinius lęšius. Išanalizuoti galimi asferinių lęšių paviršiai ir jų pranašumas prieš sferinius paviršius. Trečiajame skyriuje pateikiamas matematinis spindulių eigos modelis sferiniame paviršiuje. Ketvirtajame – matematinis spindulių eigos modelis asferiniame paviršiuje. Penktajame skyriuje lyginami kompiuterinių modelių pagalba gauti įstrižojo astigmatizmo apibūdinti rezultatai, tangentinėmis paklaidomis.
The bachelor’s thesis „The computer modeling of oblique astigmatism in spherical and aspherical lenses” consists of introduction, 5 chapters, conclusions and attachments. The thesis introduces 50 figures, 2 tables and refers to 16 literary sources. The volume of the work is 66 pages. The work summarizes the literature which describes the lens aberrations, its influence to quality of vision and reduction by using aspheric lenses. There is also included mathematical models of spherical and aspheric lenses, and analysis of oblique astigmatism in them. The introduction sets the aims and the goals of the study. The first chapter contains theoretic material about lens aberrations, the second – about spherical and aspheric lenses, the analysis about available surfaces of aspheric lenses and advantages of them. The third chapter contains mathematical model of light rays pathway in spherical lenses. The fourth chapter contains mathematical model of light rays pathway in aspheric lenses. The fifth chapter contains comparison of oblique astigmatism described as tangential errors in those two models.

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Wang, Kai. "Involvement of O-glcnacylation in lens development and cataract formation." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2010r/wang.pdf.

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Kim, Youmee. "An analysis and performance guide to Benjamin Lees's Odyssey I and II." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1199061624.

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Rayadurgam, Sripriya. "Design of a wall-less proportional counter for microdosimetry in nanometer dimensions." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/3801.

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Knowledge of energy deposition in biological cells at nanometer dimensions is essential to understand the biological effects of radiation. This work has resulted in the development of a practical tool to study such energy deposition experimentally, at nanometer dimensions. The main contribution of this research is the design of a cylindrical wall-less proportional counter of 1mm height by 1mm diameter. A wall-less detector (also called grid-walled detector) overcomes the so-called Âwall effectÂ, an experimental artifact that introduces distortions in the radiation energy measurements. An important feature of this detector that distinguishes it from other detectors is its modular design. This allows the detector to be repaired or modified, when necessary, without having to completely disassemble it. Novel design techniques were adopted resulting in a functional detector that can simulate cellular sites as small as 10 nanometers, approximately the size of many molecules in the cell. The detector was tested with a 1 microcurie sealed Am-241 source, which primarily emits monoenergetic alpha particles of energy 5.57 MeV. Microdosimetric spectra analysis for alpha particles and its delta rays from Am-241 were performed for simulated site sizes ranging from 500nm to 10nm. Initial studies to validate the detector design have confirmed good detector performance. We believe this work will serve as a vital platform for bridging the experimentally measured energy spectra to the biological effects of alpha and delta radiations.

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Sagawa, Atsushi. "New solution for well test analysis in reservoirs with permeability discontinuities." Thesis, Heriot-Watt University, 2000. http://hdl.handle.net/10399/551.

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Schork, Marion. "Kortikale Veränderungen bei Restless Legs Syndrom - eine Voxel-basierte morphometrische Untersuchung." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-65536.

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Philippi, Jeanine Nicolazzi. "Elementos para a compreensão da lei :." Florianópolis, SC, 2000. http://repositorio.ufsc.br/xmlui/handle/123456789/79084.

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Tese (Doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas.
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Martel, Letícia de Campos Velho. "Devido processo legal substantivo." Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/79998.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas. Programa de Pós-Graduação em Direito.
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Maria, Martins Silva Guimarães Ivanda. "Interação texto-leitor na escola : dialogando com os contos de Gilvan Lemos." Universidade Federal de Pernambuco, 2003. https://repositorio.ufpe.br/handle/123456789/7642.

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A presente investigação analisa a interação de alunos do Ensino Médio de uma escola pública da rede estadual com os contos de Gilvan Lemos, visando estudar as principiais dificuldades dos leitores em face da leitura literária. Revisitamos os pressupostos de abordagens teóricas que focalizam a interação texto-leitor sob prismas distintos, mas que dialogam quando discutem a leitura do ponto de vista social (Jauss, 1978), ou individual (Iser, 1979, 1996, 1998), reconhecendo os limites da interpretação (Eco, 1999). Os contos do autor pernambucano foram selecionados, tendo em vista as diferentes estratégias narrativas utilizadas que convidam o leitor a participar do jogo da ficção . Foram trabalhados cinco contos de Gilvan Lemos: A inocente farsa da vingança, Dias idos e não vividos, Missa do galo, Morte ao invasor e Coelhinhos do mato. O corpus da pesquisa é formado por 300 questionários aplicados após a leitura dos referidos contos. Na análise dos dados, selecionamos as respostas dos alunos, as quais revelaram a identificação ou a nãoidentificação do leitor com o texto literário. Os resultados da pesquisa apontam a técnica narrativa utilizada nos contos como a principal dificuldade dos alunos no ato da leitura. Diante da leitura de narrativas que apresentam uma organização discursiva pouco linear, os alunos não conseguem articular os planos da história e do discurso. Em síntese, o presente estudo propõe uma maior integração entre as contribuições da Teoria da Literatura e a escola, na medida em que discute o ato da leitura como processo dinâmico de envolvimento do leitor com o texto, considerando principalmente o enfoque de Iser. A leitura literária é abordada como um jogo, conforme a abordagem de Iser (In: Lima, 2002), em que os autores jogam com os leitores e o texto é o campo do jogo

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Pateiro, Hermenegildo Domingos dos Santos. "Uma abordagem das leis de Kepler nos ensinos básico e secundário." Master's thesis, Universidade de Évora, 2007. http://hdl.handle.net/10174/16315.

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Descrevemos de forma breve o que terá sido a vida de Johannes Kepler desde o seu nascimento até à sua morte, abordando também as suas deambulações pela Europa Central, muitas ocasionadas pelas perseguições católicas, mas que na maioria dos casos ajudaram a progredir as suas investigações. Focamos o envolvimento deste com Tycho Brahe, quanto a nós, a “verdadeira fonte” de inspiração e de talento para as descobertas de Kepler. Propomos uma metodologia de abordagem do tema, ao longo dos ensinos básico e secundário, num crescendo de complexidade, de modo a que o ensino-aprendizagem das leis de Kepler e, dos movimentos planetários se tome particularmente interessante. Explicitamos de forma clara e sucinta como nós projetámos e criámos o nosso aparato experimental. Este protótipo servirá mais como um suporte didáctico a que os professores possam recorrer, aquando da abordagem do tema “Leis de Kepler” nos diferentes níveis de ensino. /ABSTRACT - We shortly describe what probably the life of Johannes Kepler Was since his birth till his death, including his deambulations through Central Europe, mostly caused by the catholic persecutions, which helped his investigations to progress. We focus on his involvement with Tycho Brahe, in our opinion, the “real source” of inspiration and talent for Keller's discoveries. A methodology consisting of a combined scientific and pedagogic approach of the subject is proposed to be implemented in the Third cycle and Secondary level teaching in Portugal. This approach is developed in such a way that the teaching- learning process of the laws of Kepler and of the planetarium movements will become particularly interesting. We explain on a clear concise way as we projected and created our experimental display structure. This prototype will serve as one more didactic support which teachers may have as a resource, when they are approaching the subject “The Laws of Kepler” on the different teaching levels.

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Maxwell, Brian McNeilly. "Turbulent Combustion Modelling of Fast-Flames and Detonations Using Compressible LEM-LES." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34122.

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A novel approach to modelling highly compressible and reactive flows is formulated to provide high resolution closure of turbulent-scale reaction rates in the presence of very rapid transients in pressure and energy. For such flows, treatment of turbulent-micro scales are generally unattainable through traditional modelling techniques. To address this, the modelling strategy developed here is based on the Linear Eddy Model for Large Eddy Simulation (LEM-LES); a technique which has only previously been applied to weakly compressible flows. In the current formulation of the Compressible LEM-LES (CLEM-LES), special treatment of the energy balance on the model subgrid is accounted for in order for the model reaction rates to respond accordingly to strong shocks and rapid expansions, both of which may be present in reactive and supersonic flow fields. In the current study, the model implemented is verified and validated for various 1D and 2D flow configurations in a compressible Adaptive Mesh Refinement (AMR) framework. In 1D test cases, laminar and turbulent flame speeds and structure have been reproduced. Also, detonation speeds and initiation events are also captured with the model. For 2D model validation, unsteady and turbulent detonation propagation and initiation events, in a narrow channel, are simulated. Both test cases involve premixed methane-oxygen mixture at low pressures. The model is found to capture well the two-dimensional detonation cellular structure, behaviour, and initiation events that are observed in corresponding shock tube experiments. Furthermore, the effect of turbulent mixing rates is investigated though a single tuning constant. It was found that by increasing the intensity of turbulent fluctuations present, detonations exhibit larger and more irregular cell structures. Furthermore, the intensity of turbulent fluctuations is found to also have an effect on initiation events.

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Rouget, Nicolas. "LES DYNAMIQUES AGRICOLES DANS LES ESPACES URBAINS ET PERIURBAINS. DIVERSIFICATION ET STRATEGIES D'ADAPTATION DES AGRICULTURES. LES CAS DES PERIPHERIES SUD-EST DE LILLE ET NORD DE LENS." Phd thesis, Université de Nanterre - Paris X, 2008. http://tel.archives-ouvertes.fr/tel-00477267.

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L'agriculture des espaces périurbains est doublement contrainte (libéralisation économique accrue et effets de la proximité urbaine). Les contextes généraux et locaux lui offrent néanmoins l'opportunité de s'investir dans un renouvellement de ses fonctions (contextes de la durabilité et des programmes agriurbains). La question de l'engagement des exploitations dans le processus de « transition agricole » par la voie de la diversification, notamment par les services, et dans une perspective d'ancrage au territoire de la ville, constitua ainsi notre principale entrée. La typologie des trajectoires et stratégies d'adaptation établie en fonction des dynamiques des systèmes de production et de revenu et de l'intensité des relations de l'agriculture à la ville, distingue des trajectoires « d'occultation », de « spécialisation », d' « engagement dans une logique d'ouverture aux demandes citadines », de « conversion ». La territorialisation de l'agriculture, son inscription dans le territoire de la ville n'est pas la seule voie choisie d'adaptation aux contextes généraux et locaux. La diversification par les services n'est pas non plus la seule stratégie d'adaptation à la ville. La typologie des espaces agricoles souligne que la transition agricole s'opère très inégalement d'une agglomération à une autre et au sein d'une même périphérie urbaine. Les communes de la périphérie Nord de Lens et les cas belges envisagés sont très majoritairement caractérisés par une déterritorialisation des systèmes de production et de revenu. Les trajectoires observées ont été motivées, d'une part par le délitement d'un « modèle agricole minier », d'autre part par la ˝ nécessité ˝ d'assumer de volumineux quotas betteraviers. En revanche, les communes de Loos-en-Gohelle et de la périphérie lilloise sont caractérisées par des dynamiques d'appropriation de l'espace urbain par l'agriculture. A ces dynamiques contribue, au sein de l'espace lillois étudié, la valorisation des discontinuités introduites par la proximité de la frontière. Une dynamique de groupe à Loos, le « précédent endivier » en Pévèle-Mélantois ont été déterminants. L'agriculture dans ce contexte ne répond que partiellement aux attentes urbaines. L'étude, dans le cadre des agricultures déterritorialisées, souligne les difficultés de mise en concordance des représentations de l'espace entre élus et agriculteurs. En revanche, les partenariats engagés à Lille relèvent d'un processus de co-construction. Le principe d'une contractualisation entre décideurs et agriculteurs repose sur des politiques de confortement des trajectoires de diversification par les services. Les programmes engagés ne solutionnent néanmoins pas les facteurs de « décrochage » par ailleurs évoqués.

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Rouget, Nicolas. "Les dynamiques agricoles dans les espaces urbains et périurbains : diversification et stratégies d'adaptation des agricultures : les cas des périphéries Sud-est de Lille et Nord de Lens." Paris 10, 2008. https://tel.archives-ouvertes.fr/tel-00477267.

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La question de l’engagement des exploitations dans le processus de « transition agricole » par la voie de la diversification des exploitations, notamment par les services, et dans une perspective d’ancrage au territoire de la ville, constitua la principale entrée de l’étude. La typologie des trajectoires et stratégies d’adaptation établie en fonction des dynamiques des systèmes de production et de revenu et de l’intensité des relations de l’agriculture à la ville, distingue quatre groupes de trajectoires, de l’«occultation» à la «conversion». La territorialisation de l’agriculture n’est pas la seule voie choisie d’adaptation aux contextes généraux et locaux. La diversification par les services n’est pas non plus la seule stratégie d’adaptation à la ville. La typologie des espaces agricoles souligne que la transition agricole s’opère très inégalement d’une agglomération à une autre et au sein d’une même périphérie urbaine. Les communes de la périphérie Nord de Lens et les cas belges envisagés sont très majoritairement caractérisés par une déterritorialisation des systèmes de production et de revenu. En revanche, les communes de Loos-en-Gohelle et de la périphérie Est-lilloise sont caractérisées par des dynamiques d’appropriation de l’espace urbain par l’agriculture. L’étude, dans le cadre des agricultures déterritorialisées, souligne les difficultés de mise en concordance des représentations de l’espace entre élus et agriculteurs. En revanche, les partenariats engagés à Lille relèvent d’un processus de co-construction. Les programmes déployés ne solutionnent néanmoins pas les facteurs de « décrochage » par ailleurs évoqués
The question of the commitment of farming concerns into the process of “agricultural transition” through the way of the diversification of farming concerns, especially through the services, and in a view to fix itself into town territory, constituted the main reason for this study. The typology of trajectories and strategies of adaptation established according to the dynamics of income systems and to the importance of the links between agriculture and town, singles “occultation trajectories”, “specialization” ones, trajectories of “self-commitment in a logic of opening up to the urban demands”, of “conversion”. Agriculture territorialisation is not the only way chosen to adapt to general and local contexts. Diversification through services is not the only strategy of adaptation to town either. The typology of agricultural areas enhances the fact that the agricultural transition takes effect in a very unequally way from one town to another and even within the same urban periphery. On the one hand, towns in the north periphery of Lens and the considered Belgian cases are for the most important part characterized by a deterritorialisation of the income and production systems. On the other hand, the towns of Loos-en-G and those of the Lille periphery are characterized by their agricultural fixing to urban territories. The study underlines how difficult it is to make the representations of the territory concord, between the elected representatives and the farmers (as far as deterritorialised agricultures are concerned). However, the partnerships committed in Lille are a matter for a process of co-construction

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Mital, Rashmi. "Design and demonstration of a novel optical true time delay technique using polynomial cells based on white cells." Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1111161542.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xiii, 195 p.; also includes graphics (some col.) Includes bibliographical references (p. 190-195). Available online via OhioLINK's ETD Center

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Dissertations / Theses on the topic 'LEMS'

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