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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 16 of 16 for “"Radiation physics"”.
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The radiation physics, mitigation approaches and design guidelines of high-speed connectors and cables analyzed with numerical modeling, analytical formulation and measurements
… is composed of three papers, which cover the radiation and mitigation of high-speed connectors and cables analyzed with full wave simulation, numerical modeling, analytical formulation and measurements.</p><p>In the first paper, the radiation from the optical cage connector in the frequency …
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Fundamental Limits on Antenna Size for Frequency and Time Domain Applications
… antenna size and performance are limited by radiation physics, not technology. In order to understand antenna radiation and energy storage mechanisms, classical and alternative viewpoints of radiation are discussed. Unlike the common sense of classical antenna radiation, it is shown that the …
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Quantification of Fat Content and Fatty Acid Composition Using Magnetic Resonance Imaging
In obesity and several other disease scenarios, the measurement of fat accumulation in various organs and tissues has become a sought-after technique in clinical diagnostics and research. Especially, quantitative and non-invasive techniques which also provide images of accumulated fat throughout …
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Radiation exposure of human populations in villages in Russia and Belarus affected by fallout from the Chernobyl reactor
… a high pressure ionisation chamber and ordinary radiation protection instruments. These measurements were carried out at various (stationary) positions in a contaminated village in Belarus, not far from the villages in the Bryansk region. Today the radiological importance is completely dominated …
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Breast Tomosynthesis: Aspects on detection and perception of simulated lesions
The aim of this thesis was to investigate aspects on detectability of simulated lesions (microcalcifications and masses) in digital mammography (DM) and breast tomosynthesis (BT). Perception in BT image volumes were also investigated by evaluating certain reading conditions. The first study …
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fMRI for mapping the plastic somatotopy of primary somatosensory cortex - Development and clinical applications
Functional magnetic resonance imaging (fMRI) is a widely used tool for studying brain function in vivo. The technique is based on acquiring brain images sensitive to the physiological response following neural activation, and hence, allows brain activity to be examined and documented. In this …
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Measurement of Tumor Extent and Effects of Breast Compression in Digital Mammography and Breast Tomosynthesis
… both to improve image quality and to reduce the radiation dose to the breast, but it also has a negative consequence as some women refrain from mammography due to the pain associated with the examination. Since BT is a 3D technique, it was hypothesized that less breast compression force can be …
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Three-dimensional T1 quantification techniques for assessment of cartilage quality using dGEMRIC
Osteoarthritis (OA) is a common chronic disease and one of the major global causes for functional disabilities. The disease is characterized by loss and degradation of cartilage, commonly affecting the knees and hips. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) is a previously presented …
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Volumetric, Magnetic Resonance-Visible, and Radiation-Sensitive Detectors For Magnetic Resonance Image-Guided Radiation Therapy
<h1>VOLUMETRIC, MAGNETIC RESONANCE-VISIBLE, AND RADIATION-SENSITIVE DETECTORS FOR MAGNETIC RESONANCE IMAGE-GUIDED RADIATION THERAPY</h1> <p>Hannah Jungeun Lee</p> <p>Advisory Professor: Geoffrey S. Ibbott, Ph.D.</p> <p>Due to the superior soft-tissue contrast of magnetic resonance imaging (MRI) …
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Evaluation of Timepoint Assessment Schemes for Offline Adaptive Radiotherapy of the Head and Neck Using Velocity
… performed for three patients who received radiation treatment at the University of Nebraska Medical Center. These assessment schemes use a validated workflow based in Varian’s Velocity software. Assessments triggered adaptive replanning if the dose to any of seven organs-at-risk was …
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Development of a method for automating effective patient diameter estimation for digital radiography
National patient dose audit of paediatric radiographic examinations is complicated by a lack of data containing a direct measurement of the patient diameter in the examination orientation or height and weight. This has meant that National Diagnostic Reference Levels (NDRLs) for paediatric …
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Biomimetic Materials for Biomedical Applications
… (National Institute for Lasers, Plasma and Radiation Physics – Laser Department, Bucharest) Pulsed Laser Deposition has been successfully applied to deposit thin films of Sr substituted HA on Titanium substrates. The synthesized coatings displayed a uniform Sr distribution, a granular …
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Laser-driven implosion characterization by the analysis of charged-fusion-product energy spectra
Energy spectra of charged-fusion products escaping laser-imploded deuterium-tritium filled glass microballoon targets were measured with a time-of-flight (TOF) spectrometer. The TOF spectrometer was carefully designed, constructed and calibrated to simultaneously measure alpha-particles and protons.
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Chaos effects in one-dimensional hydrogen, including the high-frequency regime
The system of highly excited hydrogen in combined strong ac and dc electric fields is examined. It is shown that the production and maintainence of effectively one-dimensional states is plausible in this system. The threshold of global classical chaos is calculated using the resonance overlap …
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Exclusive Photodisintegration of 3He
<p>Kinematically complete measurements of three-body photodisintegration of $^3$He were performed at the High Intensity $\gamma$-ray Source (HI$\gamma$S) with nearly monoenergetic 15 MeV photons. The experiment relied on two-nucleon coincidence measurements in which the nucleons are emitted on …
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Numerical simulations of mass outflows from star-forming regions
… testing, and application of a two dimensional radiation magnetohydrodynamics (RMHD) code is described in detail. Well developed Eulerian hydrodynamic algorithms are used, but are implemented in a new covariant formalism which facilitates simulations in any orthogonal coordinate system. The …