Dissertations / Theses on the topic 'Active detectors'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Active detectors.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Lawrence, Ryan Christopher 1975. "Active wavefront correction in laser interferometric gravitational wave detectors." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/29308.
Includes bibliographical references (p. 239-243).
As the first generation of laser interferometric gravitational wave detectors near operation, research and development has begun on increasing the instrument's sensitivity while utilizing existing infrastructure. In the Laser Interferometer Gravitational Wave Observatory (LIGO), significant improvements are being planned for installation in 2007 to increase the sensitivity to test mass displacement, hence sensitivity to gravitational wave strain, by improved suspensions and test mass substrates, active seismic isolation, and higher input laser power. Even with the highest quality optics available today, however, finite absorption of laser power within transmissive optics, coupled with the tremendous amount of optical power circulating in various parts of the interferometer, result in critical wavefront deformations which will cripple the performance of the instrument. Discussed is a method of active wavefront correction via direct thermal actuation on optical elements of the interferometer; or, "thermally adaptive optics". A simple nichrome heating element suspended off the face of an affected optic will, through radiative heating, remove the gross axisymmetric part of the original thermal distortion. A scanning heating laser- will then be used to remove any remaining non-axisymmetric wavefront distortion, generated by inhomogeneities in the substrate's absorption, thermal conductivity, etc. This work includes a quantitative analysis of both techniques of thermal compensation, as well as the results of a proof-of-principle experiment which verified the technical feasibility of each technique.
by Ryan Christopher Lawrence.
Ph.D.
Allread, Benjamin Scott. "Real-time pro-active safety in construction." Thesis, Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/34815.
Hodgson, Michael. "Silicon carbide and diamond neutron detectors for active interrogation security applications." Thesis, University of Surrey, 2016. http://epubs.surrey.ac.uk/810650/.
Rose, Paul B. "Cherenkov detectors for transmission studies of monoenergetic high-energy photons in active interrogation applications." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54464.
Fisher, Martin John. "Epitaxial growth and characterisation of heterojunction and homojunction LEDs with InAs active regions." Thesis, Lancaster University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268062.
Van, Gorp Byron Everrett. "Force sensing integrated tip and active readout structures with improved dynamics and detection range." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22645.
Ferrarese, Lupi Federico. "Optically active Si-rich Si3N4 Mu-cavities for sensoristic applications." Doctoral thesis, Universitat de Barcelona, 2012. http://hdl.handle.net/10803/83606.
En esta tesis, realizada en el departament d' Electrònica de la Universitat de Barcelona se ha presentado un estudio detallado the las propiedades ópticas y sensoras de estructuras resonantes tipo micro-disco fabricados íntegramente en nitruro de silicio enriquecido con silicio (SRSN). El estudio se ha llevado a cabo bien en estructuras aisladas o en una configuración acoplada con una guía de onda passiva situada debajo de la cavidad. La totalidad de la estructura ha sido simulada con el fin de estudiar el comportamiento de los modos resonantes WGM soportados cuando se cambian las condiciones de contorno geómetricas y del material. Los resultado obtenidos han permitido la realización de estructuras resonantes con factores de calidad superiores a 104. El objetivo de las simulaciones ha sido el de maximizar la intensidad transmitida de los modos soportados (WGM) al final de la guía de onda. Este hito ha sido cumplido gracias a la optimización de los parámetros geómetricos relativos (el X-gap y el Z-gap). Una vez producidas las muestras, se procedió a la realización de un análisis de superficie (SEM, AFM) para evaluar la rugosidad efectiva de las estructuras y las eventuales imperfecciones geométricas. Como resultado de la optimización del material activo en términos de intensidad de fotoluminiscencia y pérdidas ópticas, se consiguieron realizar cavidades resonantes de alta emisión luminosa y buenos factores de calidad. En un nuevo montaje experimental de u-PL desarrollado íntegramente para el estudio de estos dispositivos, se obtuvieron valores máximos de Q = 1.4x104 en un rango espectral ancho en el visible. La potencia emitida en cada resonancia ha sido medida y cuantificada en un valor de nW. Este valor permite la utilización de detectores de silicio integrados. Con el fin de evaluar la sensitividad del dispositivo, se han llevado a cabo medidas de u-PL cambiando el entorno del microdisco y monitorizando el desplazamiento espectral que sufre una determinada resonancia. El resultado de estas medidas muestra un desplazamiento de 1.37 nm como consecuencia de un índice de refracción de An = 0.0038 RIU (refractive index unit).
Fernandez-Perez, Sonia. "A novel depleted monolithic active pixel sensor for future high energy physics detectors." Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/385732.
A major upgrade of the Large Hadron Collider (LHC) called High Luminosity LHC (HL-LHC) is scheduled for 2024-2026. This will lead to an increase of the luminosity by seven times the current value and to the extension of the currently ongoing physics programme. A completely new Inner Detector for the ATLAS experiment needs to be developed to withstand the extremely harsh environment at the HL-LHC. New pixel detector concepts are being investigated as a possible candidate to the inner and outer layers of the HL-LHC ATLAS Inner Detector. The use of monolithic pixel sensors in the ATLAS Inner Tracker would lead to a new era of pixel detectors as a consequence of its many advantages with respect to the current technologies. The achievement of smaller spatial resolution, lower density, bigger production yield and throughput, and smaller budget cost are the main arguments to pursue this technology. In this context, a novel Depleted Monolithic Pixel Active Detector built on a thick film Silicon-On-Insulator has been fully investigated in this thesis. Chapter 1 introduces LHC and the ATLAS experiment as well as their foreseen scenarios at the HL-LHC upgrade. This naturally motivates the stringent requirements and challenges of the closest sub-detector to the interaction point, the Inner Detector. Chapter 2 describes the basis of a tracking detector for high energy physics applications, detailing the interactions of particles with matter to the formation of a pixel detector from a semiconductor material. Then the momentum, vertex, and impact parameter resolution of a tracking detector are calculated leading to a set of requirements for the detector design. Chapter 3 describes the radiation damage in silicon detectors whose impact to the detector performance is crucial specially for HL-LHC experiments. The radiation damage in the electronics and in the silicon bulk is treated. Chapter 4 revises the current developments and trends on pixel detectors from the well established hybrid pixel technologies to the commercial CMOS pixels. The commercial CMOS pixels section describes the current technologies being considered at ATLAS: high resistivity, high voltage CMOS (currently built as hybrid and as monolithic), and monolithic CMOS-on-SOI. The latter one composes the core of study of this thesis and is described in great detail. The final chapters are dedicated to the description of the validation programme performed to the CMOS-on-SOI technology, together with characterization methods used, measurements performed, and results analysis description. Chapter 5 focuses on the measurements performed to characterize the radiation hardness of the technology against the ionizing radiation expected in the HL-LHC ATLAS detector. The crucial charge collection properties to fulfil the ATLAS detector requirements were measured and are described in Chapter 6. These measurements include leakage current, signal-to-noise ratio, collected charge, and depletion depth on unirradiated and irradiated samples. Additionally, different techniques as radioactive sources, pion beams, and laser beams were used in order to calculate the depletion depth. Chapter 7 describes the characterization of the monolithic CMOS-on-SOI in a pion beam test. The measured charge collection, charge sharing, spatial resolution, and tracking efficiency are discussed. Within the summary, an outlook towards the future of depleted monolithic active pixel sensors on silicon-on-insulator technology for high energy physics is presented.
Schmittdiel, Michael C. "Active control of a diffraction grating interferometer for microscale devices." Thesis, Available online, Georgia Institute of Technology, 2005, 2004. http://etd.gatech.edu/theses/available/etd-07102004-164021/.
Dr. William P. King, Committee Member ; Dr. F. Levent Degertekin, Committee Member ; Dr. Thomas R. Kurfess, Committee Chair.
Lyson, Kyle Joshua. "On-chip automatic tuning of CMOS active inductors for use in radio frequency integrated circuit (RFIC) applications." Thesis, Montana State University, 2006. http://etd.lib.montana.edu/etd/2006/lyson/LysonK1206.pdf.
Prakash, Tanmay. "Active Learning for Designing Detectors for Infrequently Occurring Objects in Wide-Area Satellite Imagery." Thesis, Purdue University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10639835.
For designing detectors for infrequently occurring objects in wide-area satellite imagery, we are faced with the challenge that such objects are difficult to find for the purpose of generating the needed training data. As a result, a human agent must expend an inordinate length of time in order to produce a sufficient number of labeled training data. In this dissertation, we reduce this annotation burden by drawing upon the research that has been carried out recently in the area of active learning, whereby the machine searches for human annotation those unlabeled samples that can actually improve the detector. The search is iterative: Starting with a small number of human-supplied strongly positive and negative samples, our framework scans the images and tests the candidate samples against the current decision surfaces. Only those samples that are too close to the decision surfaces are sent to the human for annotation and the new samples thus labeled used to update the decision surfaces. We have applied this framework to create detectors for pedestrian crosswalks and transmission-line towers in a cloud-based implementation in areas of over 150,000 sq km in Australia. We should also mention that a stepping stone to this work was our earlier, more direct approach to detector design in which the class discrimination features are specified by the human. This approach, which was also an exercise in exploiting volunteer-generated road maps for detecting objects that are on or along the roads, was used to create a crosswalk detector and applied to a 180,000 sq km area in Australia.
Shen, Chao. "Study of CMOS active pixel image sensor on SOI/SOS substrate /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202003%20SHEN.
Includes bibliographical references (leaves 67-69). Also available in electronic version. Access restricted to campus users.
SIDDHANTA, SABYASACHI. "Studies On Monolithic Active Pixel Sensors and Detector Performance for the Inner Tracking System Upgrade of ALICE." Doctoral thesis, Università degli Studi di Cagliari, 2014. http://hdl.handle.net/11584/266453.
Silva, Joel [Verfasser]. "Digital signal analysis for CsI(Tl) detectors and the active-target at R 3 B / Joel Silva." Mainz : Universitätsbibliothek Mainz, 2016. http://d-nb.info/1105481549/34.
Tipparaju, Venkata Satya Sai Sarma. "An active core fiber optic gas sensor using a photonic crystal hollow core fiber as a transducer." Master's thesis, Mississippi State : Mississippi State University, 2007. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06262007-164352/.
Marín, Tobón César Augusto. "PADRE pixel read-out architecture for Monolithic Active Pixel Sensor for the new ALICE Inner Tracking System in TowerJazz 180 nm technolog." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/86154.
El sub detector ITS (Inner Tracking System) del detector ALICE (A Large Ion Collider Experiment) es un detector de vértice y es el detector mas cercano al punto de interacción. Se encuentra conformado por 3 tipos de subdetectores, dos capas de pixel de silicio (Silicon Pixel Detectors), 2 capas de acumulación de silicio (Silicon Drift Detectors) y 2 capas de banda de Silicio (Silicon Strip Detectors). La función primaria del ITS es identificar y rastrear las partículas de bajo momentum transversal. El detector ITS en sus dos capas más internas están equipadas con sensores de silicio basados en píxeles híbridos. Para reemplazar esta tecnología de Píxeles, el detector ITS actual será reemplazado por un nuevo detector de una sola tecnología, ampliando su resolución espacial y mejorando el rastreo de trazas. Este nuevo detector constará de siete capas de sensores de píxeles activos monolíticos (MAPS), las cuales deberán satisfacer los requerimientos de presupuesto de materiales y ser tolerantes a mayores niveles de radiación para los nuevos escenarios de incrementos de luminosidad y mayores tasas de colisiones. Los sensores MAPS que integran el sensor de imagen y los circuitos de lectura se encuentran en la misma oblea de silicio, tienen grandes ventajas en una buena resolución de posición y un bajo presupuesto material en términos de bajo coste de producción. TowerJazz ofrece la posibilidad de una cuádruple-WELL aislando los transistores pMOS que se encuentran en la misma nWELL evitando la competencia con el electrodo de recolección, permitiendo circuitos mas complejos y compactos para ser implementados dentro de la zona activa y además posee una capa epitaxial de alta resistividad. Esta tecnología proporciona una puerta de óxido muy delgado limitando el daño superficial por la radiación haciéndolo adecuado para su uso denxiii Resúmen tro del experimento ALICE. En los últimos cuatro años se ha llevado a cabo una intensiva I+D en MAPS en el marco de la actualización del ITS de ALICE. Varios prototipos a pequeña escala se han desarrollado y probado exitosamente con rayos X, fuentes radioactivas y haces de partículas. La tolerancia a la radiación de ALICE ITS es moderada con una tolerancia de irradiación TID de 700 krad y NIEL de 1 × 1013 1 MeV neqcm¿2 , MAPS es una opción viable para la actualización del ITS. La contribución original de esta tesis es la implementación de una nueva arquitectura digital de lectura de píxeles para MAPS. Esta tesis presenta un codificador asíncrono de direcciones (arquitectura basada en la supresión de ceros transmitiendo la dirección de los píxeles excitados denominada PADRE) para la arquitectura ALPIDE, el autor también hizo una contribución significativa en el ensamblaje y veri- ficación de circuitos. PADRE es la principal investigación del autor, basada en un codificador de prioridad jerárquica de cuatro entradas y es una alternativa a la arquitectura de lectura rolling-shutter. Además de los prototipos a pequeña escala, también se han desarrollado prototipos a escala completa a las necesidades del detector ITS (15 mm y 30 mm) empleando un nuevo circuito de lectura basado en la versión personalizada del circuito PADRE. El pALPIDEfs fue el primer prototipo a escala completa y se caracterizó obteniendo un tiempo de lectura de la matriz por debajo de 4 µs y un consumo de energía en el orden de 80 mWcm¿2 . En general, los resultados obtenidos representan un avance significativo de la tecnología MAPS en cuanto al consumo de energía, velocidad de lectura, tiempo de recolección de carga y tolerancia a la radiación. El sensor pALPIDE2 ha demostrado ser una opción muy atractiva para el nuevo detector ITS, satisfaciendo los requerimientos en términos de eficiencia de detección, fake-hit rate y resolución de posición, ya que su rendimiento no puede alcanzarse mediante prototipos basados en la arquitectura de lectura tradicionales como es
El subdetector ITS (Inner Tracking System) del detector ALICE (A Large Ion Collider Experiment) és un detector de vèrtex i és el detector mes proper al punt d'interacció. Es troba conformat per 3 tipus de subdetectors, dues capes de píxel de silici (Silicon Pixel Detectors), 2 capes d'acumulació de silici (Silicon Drift Detectors) i 2 capes de banda de Silici (Silicon Strip Detectors). La funció primària del ITS és identificar i rastrejar les partícules de baix moment transversal. El detector ITS en les seues dues capes més internes estan equipades amb sensors de silici basats en píxels híbrids. Per a reemplaçar aquesta tecnologia de Píxels, el detector ITS actual serà reemplaçat per un nou detector d'una sola tecnologia, ampliant la seua resolució espacial i millorant el rastreig de traces. Aquest nou detector constarà de set capes de sensors de píxels actius monolítics (MAPS), les quals hauran de satisfer els requeriments de pressupost de materials i ser tolerants a majors nivells de radiació per als nous escenaris d'increments de lluminositat i majors taxes de col·lisions. Els sensors MAPS que integren el sensor d'imatge i els circuits de lectura es troben en la mateixa hòstia de silici, tenen grans avantatges en una bona resolució de posició i un baix pressupost material en termes de baix cost de producció. TowerJazz ofereix la possibilitat d'una quàdruple-WELL aïllant els transistors pMOS que es troben en la mateixa nWELL evitant la competència amb l'elèctrode de recol·lecció, permetent circuits mes complexos i compactes per a ser implementats dins de la zona activa i a més posseeix una capa epitaxial d'alta resistivitat. Aquesta tecnologia proporciona una porta d'òxid molt prim limitant el dany superficial per la radiació fent-ho adequat per al seu ús dins de l'- experiment ALICE. En els últims quatre anys s'ha dut a terme una intensiva R+D en MAPS en el marc de l'actualització del ITS d'ALICE. Diversos prototips a petita escala s'han desenvolupat i provat ix Resum reeixidament amb rajos X, fonts radioactives i feixos de partícules. La tolerància a la radiació d'ALICE ITS és moderada amb una tolerància d'irradiació TID de 700 krad i NIEL d'1× 1013 1MeV neqcm¿2 , MAPS és una opció viable per a l'actualització del ITS. La contribució original d'aquesta tesi és la implementació d'una nova arquitectura digital de lectura de píxels per a MAPS. Aquesta tesi presenta un codificador asíncron d'adreces (arquitectura basada en la supressió de zeros transmetent l'adreça dels píxels excitats denominada PADRE) per a l'arquitectura ALPIDE, l'autor també va fer una contribució significativa en l'assemblatge i verificació de circuits. PADRE és la principal recerca de l'autor, basada en un codificador de prioritat jeràrquica de quatre entrades i és una alternativa a l'arquitectura de lectura rolling-shutter. A més dels prototips a petita escala, també s'han desenvolupat prototips a escala completa a les necessitats del detector ITS (15 mm i 30 mm) emprant un nou circuit de lectura basat en la versió personalitzada del circuit PADRE. El pALPIDEfs va ser el primer prototip a escala completa i es va caracteritzar obtenint un temps de lectura de la matriu per sota de 4 µs i un consum d'energia en l'ordre de 80 mWcm¿2 . En general, els resultats obtinguts representen un avanç significatiu de la tecnologia MAPS quant al consum d'energia, velocitat de lectura, temps de recol·lecció de càrrega i tolerància a la radiació. El sensor pALPIDE2 ha demostrat ser una opció molt atractiva per al nou detector ITS, satisfent els requeriments en termes d'eficiència de detecció, fake-hit rate i resolució de posició, ja que el seu rendiment no pot aconseguir-se mitjançant prototips basats en l'arquitectura de lectura tradicionals com és el rolling-shutter dissenyat en la mateixa tecnologia. Per aquesta raó, la R+D en els prototips ALPIDE ha continuat amb l'objectiu d'optimitza
Marín Tobón, CA. (2017). PADRE pixel read-out architecture for Monolithic Active Pixel Sensor for the new ALICE Inner Tracking System in TowerJazz 180 nm technolog [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86154
TESIS
Marks, Eric. "Active Safety Leading Indicators for Human-Equipment Interaction on Construction Sites." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51841.
BADARACCO, FRANCESCA. "Newtonian Noise studies in 2nd and 3rd generation gravitational-wave interferometric detectors." Doctoral thesis, Gran Sasso Science Institute, 2021. http://hdl.handle.net/20.500.12571/16065.
GALELLI, CLAUDIO. "INVESTIGATING THE ORIGINS OF UHECRS USING THE PIERRE AUGER OBSERVATORY AND PALEO-DETECTORS." Doctoral thesis, Università degli Studi di Milano, 2023. https://hdl.handle.net/2434/954141.
Ricci, Riccardo. "Study of bent monolithic active pixel sensors for the ALICE inner tracking system 3." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23514/.
Bao, Yuanye. "Development and Test of High-Temperature Piezoelectric Wafer Active Sensors for Structural Health Monitoring." Thesis, University of North Texas, 2014. https://digital.library.unt.edu/ark:/67531/metadc799504/.
Bergbauer, Bettina. "Study of macroscopic and microscopic homogeneity of DEPFET X-ray detectors." Doctoral thesis, Universitätsbibliothek Chemnitz, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-193814.
McBeth, Rafe A. "Active Radiation Detectors for Use in Space Beyond Low Earth Orbit| Spatial and Energy Resolution Requirements and Methods for Heavy Ion Charge Classification." Thesis, Colorado State University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10604769.
Space radiation exposure to astronauts will need to be carefully monitored on future missions beyond low earth orbit. NASA has proposed an updated radiation risk framework that takes into account a significant amount of radiobiological and heavy ion track structure information. These models require active radiation detection systems to measure the energy and ion charge Z.
However, current radiation detection systems cannot meet these demands. The aim of this study was to investigate several topics that will help next generation detection systems meet the NASA objectives. Specifically, this work investigates the required spatial resolution to avoid coincident events in a detector, the effects of energy straggling and conversion of dose from silicon to water, and methods for ion identification (Z) using machine learning.
The main results of this dissertation are as follows: 1. Spatial resolution on the order of 0.1 cm is required for active space radiation detectors to have high confidence in identifying individual particles, i.e., to eliminate coincident events. 2. Energy resolution of a detector system will be limited by energy straggling effects and the conversion of dose in silicon to dose in biological tissue (water). 3. Machine learning methods show strong promise for identification of ion charge (Z) with simple detector designs.
Peiffer, Johann Peter. "Liquid argon as active shielding and coolant for bare germanium detectors a novel background suppression method for the Gerda 0(nu/beta/beta) experiment /." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:16-opus-74878.
Demur, Romain. "Apport de l'optique non linéaire à l'imagerie infrarouge pour la détection de cibles à longue distance." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS166/document.
There is a wide range of applications in active infrared detection technologies in defense and security. However, the limited range available by these systems limits their developments. Increasing sensors sensitivity is a key milestone to improve this range. Indeed, noise in infrared detectors is much higher than for visible detectors due to some physical and technological issues. The key idea of this manuscript is to use nonlinear optical technologies to convert the infrared signal to detect into the visible spectrum and use all the benefits of silicon based sensors. Recent advances in optical crystals and in pump laser regimes bring renewed interest to upconversion detection for some specific application cases identified in this thesis. A novel and easy method to improve the number of converted modes has been proposed after a careful study of multimode conversion both temporally and spatially. In order to give figures on detection improvement using upconversion, we conducted a theoretical and numerical study of the multimode conversion as well as two sets of experiments. The first one, using conversion in an OP-GaAs crystal and a monodetector addresses mid-infrared spectroscopy applications. The second one addresses active imaging applications for target recognition and identification in the near-infrared. By using a PPLN crystal, the near-infrared image is detected on a low noise CMOS camera. A key milestone of this work is the sensitivity improvement of such a detection. Sensitivities obtained in each experiment are one order of magnitude better than with direct detection using common infrared sensors
Krumpholc, Lukáš. "Metody segmentace biomedicinských obrazových signálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218063.
Nachab, Abdellatif. "Etudes expérimentales et modélisations Monte Carlo de l'auto-absorption gamma et de la dosimétrie active par capteurs CMOS." Phd thesis, Université Louis Pasteur - Strasbourg I, 2003. http://tel.archives-ouvertes.fr/in2p3-00023644.
Suwit, Pulthasthan Information Technology & Electrical Engineering Australian Defence Force Academy UNSW. "Optimal placement of sensor and actuator for sound-structure interaction system." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Information Technology and Electrical Engineering, 2006. http://handle.unsw.edu.au/1959.4/38741.
Lu, Qi Charles. "Active tamper-detector hardware mechanism and FPGA implementation /." Diss., Online access via UMI:, 2006.
Jalasutram, Srikanth. "Design of an intelligent posture guidance system for workspace seating." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41117.
Ermeneux, Louis. "Dosimétrie des systèmes IRM-LINAC utilisés en radiothérapie externe : caractérisation des faisceaux et évaluation des distributions de dose." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPASP005.
MR-LINAC are radiotherapy devices that combine a linear accelerator (LINAC) and a magnetic resonance imager (MRI), allowing an improved tumor tracking. Dosimetric issues associated with the presence of the static magnetic field have been discussed in the literature. The aim of this thesis is to develop dosimetric tools and robust protocols for use on MRI-LINACs to enhance the knowledge of the doses delivered to patients treated with these devices. The first part of the work focuses on determining output factors (OF) in small fields on this device and studying detectors' responses. No significant variation in response was observed for EBT3 films exposed to different durations in the presence of the magnetic field (0.35 T). This high-resolution 2D detector was then used to perform several series of OF measurements on an MRidian MR-LINAC, which were then compared with measurements using active detectors (ionization chambers, diodes, microdiamond) as well as with data from the treatment planning system (TPS). A good agreement was observed between the measured OF and those calculated by the TPS for field sizes larger than or equal to 2.5x2.5 cm²; an underestimation of the TPS OF was observed for smaller field sizes (0.83x0.83 cm²: 6% for films and f 4% on average for solid active detectors). After applying TRS483 correction factors, measurements with active detectors converge with those obtained with films. These discrepancies with the TPS suggest the need for a more robust adjustment of the TPS algorithm for small fields. Measurements were complemented by Monte Carlo simulations using the Geant4 code to establish correction factors in the presence of a magnetic field for active detectors. The second part focuses on the feasibility of MRI reading of TruView dosimetric gels (ModusQA) manufactured in the laboratory to evaluate dose distributions. These gels, characterized by MRI reading (measuring T2 relaxation time), exhibited a dose-response linearity up to 7 Gy, along with relatively low sensitivity compared to the literature. Significant thermal sensitivity and gel inhomogeneity between the gel surface and deeper layers were observed in non-irradiated gels, and protocols were implemented to address these issues. The feasibility of using dosimetric gels for patient quality control in MR-Linac has been demonstrated, but an enhancement of gel sensitivity is required to achieve reliable dosimetry with this protocol
Giebels, Berrie. "A contribution to gamma-ray astronomy of GeV-TeV Active Galaxies with Fermi and H.E.S.S." Habilitation à diriger des recherches, Ecole Polytechnique X, 2011. http://tel.archives-ouvertes.fr/tel-00672596.
Silva, Angel Humberto Cruz. "Search for multiple neutrino flares from Active Galactic Nuclei with the IceCube detector." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17611.
Active Galactic Nuclei are among the best candidate sources for high-energy cosmic rays. High-energy neutrinos are expected to be produced in these sources via interactions of cosmic rays with matter or photon fields present in the source vicinity. The resulting neutrino flux may exhibit time variability on the same time scales than the ones observed in the electromagnetic radiation that is emitted from these sources. Time variability can be taken into account in high-energy neutrino searches in order to increase their detection probability with respect to search methods that include only energy and spatial information. In this work, two new methods are developed to look for high-energy neutrino flares emitted from Active Galactic Nuclei: the Multi-flare and Multi-flare stacking method. The Multi-flare method is designed to be sensitive not only to one bright flare emitted from a single source, as considered in other existing search methods, but also to several weak flares that might not be detected individually. This is achieved by developing a likelihood stacking approach that analyzes the cumulative neutrino emission from several flares. This method does not assume a-priori time coincidences with photon flares observed in the electromagnetic spectrum, allowing uncorrelated neutrino emission with different flare durations as considered in some emission models. The Multi-flare stacking method is an extension of the Multi-flare method to include several sources that might be too weak for individual detection. The two search methods are applied to a pre-selected list of Active Galactic Nuclei using data of the IceCube Neutrino Observatory (May-2009 to May 2012). No statistically significant neutrino flares are detected and fluence upper limits are calculated for each selected source. These limits are on average a factor of two better than previous upper limits from single-flare searches.
Zhang, Liang. "Development of a CMOS pixel sensor for the outer layers of the ILC vertex detector." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01068494.
Dritsa, Christina Anna. "Design of the Micro Vertex Detector of the CBM experiment : development of a detector response model and feasibility studies of open charm measurement." Strasbourg, 2011. http://www.theses.fr/2011STRA6239.
The CBM experiment (Compressed Baryonic Matter), one of the main experiments of the future FAIR accelerator facility (Darmstadt, Germany), aims in studying the phase diagram of nuclear matter in the region of high baryonic densities and moderate temperatures. Among the core physics goals is the study of the production and propagation of open charm particles, like D-mesons (particles containing one charm quark and one light quark) in heavy ion collisions. The measurements of these charmed mesons require the use of an excellent precision vertex detector. The present thesis is a contribution to the design and development of this detection device called MVD (Micro Vertex Detector). It is focused on three different parts. The first one concerns the experimental characterisation of the response of MAPS (Monolithic Active Pixel Sensors) sensors, composing the MVD detector stations, to the passage of charged particles. The second deals with the development of a realistic detector response model for the MVD detector. The last part focuses on a detailed feasibility study of open charm particle measurements in heavy ion collisions. The results demonstrate the feasibility of open charm particle measurements and allow assessing the expected performances and the limitations of the experiment
Jorge, José Hermínio Campos. "Detecção activa de obstáculos móveis para apoio à condução." Master's thesis, Universidade de Aveiro, 2008. http://hdl.handle.net/10773/2014.
Este documento descreve um trabalho desenvolvido no âmbito da tese de Mestrado, ano lectivo de 2007-08, do Mestrado Integrado de Engenharia Electrónica e Telecomunicações da Universidade de Aveiro. O trabalho realizado foi no sentido de desenvolver um sistema de detecção de obstáculos móveis baseado em ultra-sons, para aplicar num veículo cujo principal objectivo é participar na prova Eco-Maratona Shell. Pretendia-se com este sistema detectar veículos em aproximação pela retaguarda e avisar ao piloto através de mecanismos de apoio. Pretendia-se também determinar qual a velocidade de aproximação e qual o quadrante de aproximação em relação ao eixo de direcção do Ícaro. Durante a realização deste projecto, grande parte dos esforços foram no sentido de construir um sistema de detecção de obstáculos que permitisse apenas, a aquisição de ecos provenientes de direcções paralelas ao solo, focalizando o máximo de energia possível em torno dos 0 graus. A autonomia do sistema também foi tida em conta, pois o sistema foi idealizado para um veículo automóvel, tendo como única fonte energética a bateria. Deste trabalho, resultou um protótipo para o sistema de detecção com bastantes potencialidades para a aplicação. No entanto ainda carece de testes efectuados em movimento, isto é, em condições reais, para colmatar qualquer problema detectado.
Ultra-sounds are a path to detect obstacles, but there are various ways to use them to that goal. In this work, we evaluate some devices based in ultra-sonic transducers and compare them to achieve a good performance in obstacle detection and distance determination as well. A Shell Eco-Marathon driver must have the perception of the rear distance object , this is given by ears and eyes. The vision of the rear objects is given by the car mirrors, but in this case is also given by a led´s panel, the earing perception is given by sounds produced in function of the direction of the rear object. This system is to be applied to a car and must be autonomous, there are a group of devices to reach a system based only on the car battery in terms of energy.
Salzillo, Vincenzo. "“Myocontrol of Prosthetic Hands: Enforcing Active Learning by a Machine Learning based Fault Detector”." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Voutsinas, Georgios. "Optimisation of the ILC vertex detector and study of the Higgs couplings." Thesis, Strasbourg, 2012. http://www.theses.fr/2012STRAE053/document.
This thesis is a contribution to the " Detector Baseline Document ", describing the ILD detector which is intendedfor the International Linear Collider (ILC).The physics goals of the ILD call for a vertex detector (VXD) particularly light, rapid and very granular allowing toreach an unprecedented resolution on the impact parameter of the tracks that reconstruct the particles producedin the studied interactions. The principle goal of this thesis is to show how to optimise the parameters of the VXDin the case that is composed of Active Pixel Sensors manufactured in industrial CMOS technology (CAPS). Thiswork has been realised by studying the sensitivity of the performance of the heavy flavour tagging and theprecision on the hadronic branching fractions of the Higgs boson as a function of different sets of VXDparameters.The specifications of the VXD, particularly ambitious, call for the development of a novel silicon pixel sensorstechnology, the CAPS, which was pioneered by the PICSEL group of IPHC. The readout speed and the influenceof the fabrication parameters have been studied in this thesis, and CAPS prototypes have been characterised intest beams. Finally, the tracking performance of a CAPS based VXD has been evaluated with simulation studies
GIAMPAOLO, RAFFAELE AARON. "A novel fully depleted monolithic active CMOS microstrip sensor." Doctoral thesis, Politecnico di Torino, 2022. http://hdl.handle.net/11583/2959959.
Wang, H. (Hongbo). "Silicon X-ray smart sensor micromodule and microsystem." Doctoral thesis, University of Oulu, 2002. http://urn.fi/urn:isbn:951426746X.
Martinson, Eric Beowulf. "Acoustical Awareness for Intelligent Robotic Action." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19724.
Ndube, Ncediwe. "Determination of fumonisins in maize by High Performance Liquid Chromatography with fluorescence and ultraviolet detection of o-phthaldialdehyde, naphthalene-2,3-dicarboxaldehyde and dansyl chloride derivatives." Thesis, University of the Western Cape, 2011. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_2588_1320667169.
ŠULJIĆ, MILJENKO. "Study of Monolithic Active Pixel Sensors for the Upgrade of the ALICE Inner Tracking System." Doctoral thesis, Università degli Studi di Trieste, 2018. http://hdl.handle.net/11368/2918673.
Wittel, Holger [Verfasser]. "Active and passive reduction of high order modes in the gravitational wave detector GEO 600 / Holger Wittel." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1080249192/34.
Mlwilo, Nolasco Anton. "Radiometric characterisation of vineyard soils, Western Cape, South Africa." Thesis, University of the Western Cape, 2010. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6358_1318594333.
Joseph, Angelo Daniel. "Radiometric study of soil: the systematic effects." Thesis, University of the Western Cape, 2007. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6805_1248251582.
The natural ²
³
â¸U, ²
³
²
Th and â´°
K radioactive content of vineyard soil was measured with an in-situ gamma-ray detector. The activity concentration measured with the in-situ detector are normalized using the laboratory-determined activity concentrations of several samples from the vineyard site. To determine the activity concentration of a particular soil sample, the gamma-ray photopeak detection efficiencies are required. In this work, the detection efficiencies were derived for each soil sample using gamma-ray photopeaks associated with the radionuclide of ²
³
â¸U, ²
³
²
Th present in the sample, and the â´°
K, 1460.8 keV gamma-ray peak, from KCl salt.
Wong, Winnie. "A Hybrid Pixel Detector ASIC with Energy Binning for Real-Time, Spectroscopic Dose Measurements." Doctoral thesis, Mittuniversitetet, Institutionen för informationsteknologi och medier, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-16171.
Kozič, Antoni. "Investigation of AIIIBV heterostructures under the action of microwave radiation." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2008. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2008~D_20080723_093503-68603.
Disertacijoje nagrinėjama, kaip padidinti susiaurintų spinduliuotės jutiklių jautrį. Taip pat disertacijoje siekiama ištirti mikrobangų spinduliuotės poveikį susiaurintiems puslaidininkiniams dariniams ir atskleisti stebimų efektų fizinę prigimtį bei nustatyti bandinių struktūros įtaką detektuojamo signalo dydžiui. Darbe sprendžiami tokie pagrindiniai uždaviniai: tiriamos įvairialyčių susiaurintų puslaidininkinių darinių savybės, priklausančios nuo darinių sluoksnių kokybės ir puslaidininkinių medžiagų parametrų bei analizuojamos savybės, priklausančios nuo stipriai legiruoto puslaidininkinio sluoksnio laidumo, nuo skiriamojo sluoksnio storio ir nuo sklendės pobūdžio metalizacijos. Siekiant užsibrėžto tikslo, buvo gaminami ir tiriami susiaurinti skirtingi įvairialyčiai dariniai (AlGaAs/GaAs, AlGaAs/InGaAs/GaAs) ir n-GaAs dariniai. Disertaciją sudaro penki skyriai, kurių paskutinis – rezultatų apibendrinimas. Pirmajame (įvadiniame) skyriuje nagrinėjamas problemos aktualumas, formuluojamas darbo tikslas bei uždaviniai, aprašomas mokslinis darbo naujumas, pristatomi autoriaus pranešimai, disertacijos struktūra. Antrasis skyrius skirtas literatūros apžvalgai. Jame apžvelgiami elektromagnetinės spinduliuotės detektavimo principai, aptariamos šiluminės ir bigradientinės elektrovaros susidarymo priežastys, AlGaAs/GaAs įvairialytė sandūra, selektyvusis legiravimas bei puslaidininkinių prietaisų fizikinės galimybės. Trečiajame skyriuje pateikta eksperimento tyrimo metodika. Išsamiai... [toliau žr. visą tekstą]
Villanueva, Joselin. "Contribution a la télémetrie optique active pour l'aide aux déplacements des non-voyants." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00598605.
Mauss, Benoit. "Réactions élastiques et inélastiques résonantes pour la caractérisation expérimentale de la cible active ACTAR TPC." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC226/document.
ACTAR TPC (ACtive TARget and Time Projection Chamber) is a next generation active target that was designed and built at GANIL (Grand Accélérateur d'Ions Lourds). Active targets are gaseous targets in which the gas is also used to track charged particles following the principles of time projection chambers (TPC). The TPC of ACTAR has a segmented anode of 16384 2 mm side square pixels. The high density of pixels is processed using the GET (General Electronics for TPCs) electronic system. This system also digitizes the signals over a time interval, enabling a full 3D event reconstruction. An eight time smaller demonstrator was first built to verify the electronics operation and the mechanical design. ACTAR TPC's final design was based on results obtained with the demonstrator which was tested using 6Li, 24Mg and 58Ni beams. The commissioning of ACTAR TPC was then carried out for the case of resonant scattering on a proton target using 18O and 20Ne beams. A track reconstruction algorithm is used to extract the angles and energies of the ions involved in the reactions. Results are compared to previous data to determine the detection system performances. Comparing the commissioning data with R matrix calculations, excitation functions resolutions in different cases are obtained. The use of ACTAR TPC is validated for future experiments. Furthermore, alpha clustering was studied in 10B through the resonant scattering 6Li + 4He, carried out with the demonstrator. Two resonances at 8.58 MeV and 9.52 MeV are observed for the first time in elastic scattering with this reaction channel