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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 20 of 22 for “"Backscatter Coefficient"”.
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Ultrasonic backscatter coefficient quantitative estimates from Chinese hamster ovary and BALB/3T3 cell pellet biophantoms
… is introduced and applied to the ultrasonic backscatter coefficient (BSC) estimate using Chinese hamster ovary (CHO), and new and old 3T3 cells. Also introduced, for its geometrical similarities to eukaryotic cells, is a concentric sphere scattering model. BSC estimates from cell pellet …
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New Developments on Quantitative Imaging Using Ultrasonic Waves
… notable approaches are acoustic tomography and backscatter coefficient analysis. However, these techniques suffer from limitations that keep them from becoming widely used clinical tools. This dissertation presents several developments relevant to quantitative ultrasonic imaging using both …
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Lidar remote sensing of aerosol and ozone profiles and application to air quality studies in New York City area
… of the correlation between ceilometer attenuated backscatter coefficients and ground PM2.5, and aerosol homogeneity. Results show better overall correlation between attenuated backscatter and ground PM2.5 in summer, with less degradation in correlation with height during summer. Seasonal variation …
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High frequency ultrasonic characterization of human skin In vivo
… ultrasonic methods using the attenuation coefficient, backscatter coefficient, and echo envelope statistics were studied for their potential to characterize human skin tissues in vivo. A high frequency ultrasound system was developed using polymer transducers, a pulser/receiver, high-speed …
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Investigation of tropospheric arctic aerosol and mixed-phase clouds using airborne lidar technique
… calculation of the particle extinction and backscatter coefficient profiles with corresponding lidar ratio profiles characteristic for the arctic air was possible. The comparison of these lidar results with the results of other in-situ and remote instrumentation (ground based Koldewey …
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Backscatter And Attenuation Properties Of Mammalian Brain Tissues
… of mammalian brain tissues focusing on backscatter and attenuation. Orientation dependence and spatial averaging of data were analyzed using the same method resulting from insertion of tissue sample between a transducer and a reference reflector. Apparent Backscatter Transfer Function …
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Semiparametric Inference
… and in the context of ultrasound safety study, backscatter coefficient vs. frequency study as well as a pharmacokinetics study.
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The Polarimetric Impulse Response and Convolutional Model for the Remote Sensing of Layered Vegetation
… physics-based model to compute the radar backscatter from forest canopies. Several models attempt to predict the backscatter coefficient for random forest canopies by using the Vector Radiative Transfer (VRT) Theory with success, however, these models often rely on purely time-harmonic …
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The Ultrasonic Characterization of Shear Thickening Suspensions
… phase velocity, and the frequency-dependent backscatter properties of the suspensions of cornstarch are reported. Initially counterintuitive results including negative: phase velocity) dispersion and a decrease in the measured backscatter coefficient with increasing particle concentration are …
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Measuring the absolute concentration of particles in suspension using high frequency B-mode ultrasound imaging
… type differential is also performed by using the backscatter coefficient. The method is demonstrated by measuring microsphere suspensions as well as human T cell suspensions using a mechanically scanned single element transducer imaging system and a VisualSonics Vevo 2100. The proposed method has …
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Tropospheric aerosol detection over Southern Ireland using a backscatter Raman lidar
… test, Rayleigh test and zero bin test. Raman backscatter coefficients, extinction coefficients and lidar ratio were measured from April 2010 to May 2011 and February 2012 to June 2012. Statistical analysis of the profiles over these periods provided new information about the typical …
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Characteristics of blood vessel wall and atherosclerosis using high frequency ultrasound signals
… signal, such as velocity, attenuation, and backscatter coefficient are useful to characterize the material or tissues. Atherosclerosis is a condition that results in the thickening and hardening of arteries. It involves deposits of fatty substances, cholesterol, cellular products, calcium …
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Examining ultrasonic scattering mechanisms in fatty liver parenchyma via histopathological liver image
Made available in DSpace on 2022-01-12T22:35:22Z (GMT). No. of bitstreams: 2 WU-THESIS-2021.pdf: 12439545 bytes, checksum: fbbf78652158463bdab560c95e9f7416 (MD5) LICENSE.txt: 4206 bytes, checksum: 0dec3c8284a29e698ce057a3f4d3f70c (MD5) Previous issue date: 2021-07-23
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L'apport de la télédétection à un modèle de neige appliqué à un système d'aide à la gestion des barrages dans le sud du Québec
… was developed.The improvement of the Nash coefficient and the root mean square error for spring 2004 to 2007 for the simulations with the approach developed compared with streamflow simulated without remote sensing is 0.11 and 21% on the optimized watershed (du Nord) and 0.13 and 22% on the …
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Ultrasonic Characterization of Human Coronary Arteries and Atherosclerotic Plaques
… to yield measurements of the apparent integrated backscatter from coronary arteries and atherosclerotic plaques. Studies of the radial apparent backscatter carried out in the acoustic microscope confirmed trends observed in clinical radial intravascular ultrasound; in contrast, acoustic microscopy …
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Non-invasive characterization of bone tissue and modeling of bone at micron and sub-micron levels
… a specially written program which gives the backscatter coefficient (BSC) at a certain frequency is used here. The result shows that ultrasound hold promising potential to identify bone region and therefore it can be applied to capture growth of bone tissue in-vivo. In addition to ultrasound, …
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Effect size estimation and robust classification for irregularly sampled functional data
… in ultrasound quantitative ultrasound, backscatter coefficient vs. frequency functional data, commonly obtained as irregular form and public dataset with artificial contamination. We also show how to implement proposed classifier in R.
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Using two-dimensional impedance maps to study acoustic properties of tissue microstructure
… monitoring therapy. In one approach to QUS, the backscatter coefficient (BSC) from a tissue is utilized to quantify and classify tissue state. The BSC is a fundamental property of a tissue based on the frequency power spectrum estimated from the RF signals corresponding to ultrasonic backscatter. …
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Airborne lidar observations of tropospheric arctic clouds
… in models. In the framework of the PhD, elastic backscatter and depolarization lidar observations of Arctic clouds were performed during the international Arctic Study of Tropospheric Aerosol, Clouds and Radiation (ASTAR) from Svalbard in March and April 2007. Clouds were probed above the …
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Ecosystem impacts of variable recruitment in Antarctic krill investigated with long-term monitoring and archived ADCP backscatter data
… a krill predator population, and I use archived backscatter data from an Acoustic Doppler Current Profiler (ADCP) to investigate biotic and abiotic drivers of summer krill distribution along the mid-to-coastal shelf region of the western Antarctic Peninsula.In Chapter 1, my coauthors and I …
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