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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Comparison of measured and Monte Carlo-calculated peak scatter factors for 10X10 cm2 field size in 6 MV and 18 MV photon beams

Chung, Eunah January 2009 (has links)
No description available.
152

Three-dimensional dose reconstruction using non- transmission portal dosimetry and Monte Carlo calculations

Holmes, Joseph January 2010 (has links)
No description available.
153

Measurement driven, electron beam modeling and commissioning for a Monte Carlo treatment planning system with improved accuracy

Thébaut, Jonathan January 2009 (has links)
No description available.
154

Low Z target optimization for spatial resolution improvement in planar imaging and cone-beam CT

Connell, Tanner January 2009 (has links)
No description available.
155

Scatter factors and peak scatter factors for cobalt-60, 6 MV, 10, and 18 MV photon beams

Abdel-Rahman, Wamied January 1999 (has links)
No description available.
156

A study of the build-up region megavoltage radiation beams /

Abdel-Rahman, Wamied January 2004 (has links)
No description available.
157

Monte Carlo treatment planning with modulated electron radiotherapy: framework development and application

Alexander, Andrew William January 2012 (has links)
No description available.
158

Identical bands in tantalum-177 and high spin states of ytterbium-170 and ytterbium-171

Unknown Date (has links)
High spin states of an odd-proton, an odd-neutron, and an even-even rare-earth nucleus have been investigated using the FN Tandem-Superconducting Linear Accelerator facility at Florida State University. Each $\gamma$-$\gamma$ coincidence experiment was performed using all or part of the Pitt-FSU $\gamma$ array consisting of up to 10 escape suppressed high purity germanium (HPGe) detectors. The nucleus $\sp{177}$Ta was produced with the reaction $\sp{170}$Er($\sp{11}$B,4n) at 55 and 60 MeV. From this experiment, 88 new $\gamma$-rays have been assigned to this nucleus. Investigation of normal deformed identical bands and the $h\sb{9/2}$ bandcrossing anomaly were performed. The nucleus $\sp{175}$Ta was produced using the reaction $\sp{170}$Er($\sp{11}$B,6n) at 80 MeV in a further investigation of the $h\sb{9/2}$ anomaly. High spin states of $\sp{170}$Yb and $\sp{171}$Yb were produced using the reaction $\sp{170}$Er($\alpha,xn$) at 40 MeV and 35 MeV, respectively. These experiments resulted in 67 new $\gamma$-rays being assigned to the even-even nucleus, and 110 new $\gamma$-rays being assigned to the odd-A nucleus. Angular correlations have been measured in the determination of level spins. Configuration assignments are made for the rotational structures in terms of single particle Nilsson states, and a detailed Cranked Shell Model (CSM) analysis has been performed in each case. In addition, Projected Shell Model (PSM) calculations are presented and compared with the experimental data. Transition strength ratios have been measured and compared with theory. / Source: Dissertation Abstracts International, Volume: 57-04, Section: B, page: 2645. / Major Professor: Mark A. Riley. / Thesis (Ph.D.)--The Florida State University, 1996.
159

RADIATION DAMAGE OF DNA CONSTITUENTS: ESR STUDY OF THE ADENOSINE: 5-IODOURACIL COCRYSTAL

Unknown Date (has links)
Single cocrystals of adenosine:5-iodouracil and partially deuterated adenosine:5-iodouracil were irradiated at 4.2K, 77K, and 300K with X-rays from a 3Mev Van de Graaff electron accelerator. Several types of free radicals were produced by the radiation and were studied by X-Band and Q-Band ESR from 77K to 300K. Six radicals were identified. Two electron addition products (radicals I1 and As1) and one electron abstraction product (radical I2) are stabilized at 77K. At room temperature two hydrogen addition radicals (I3 and As2) and a "singlet" radical (As3) are stabilized. Upon annealing to 165K after low temperature irradiation, radicals I1 and I2 decay to nonparamagnetic species. Radical As1 remains stable from 77K to 240K. From 240K to 300K the As1 radical decays and radicals As2 and I3 gradually grow in. Irradiation and observation at room temperature produces predominantly a "singlet" radical (As3). The electron addition radical, I1, is a (sigma)*-type radical that presents the unpaired electon spin density localized mainly on the iodine atom. This radical does not de-halogenate, to produce the reactive uracilyl radical, but instead it decays into a non paramagnetic species when annealed from 77K to 300K. The low temperature radical population obtained in this cocrystal and the subsequent radical reactions upon annealing, contradict the hypothesis that, in the presence of purine:pyrimidine stacking interactions, electrons are transfered to the pyrimidines while holes are transfered to the purines. / Source: Dissertation Abstracts International, Volume: 47-05, Section: B, page: 2043. / Thesis (Ph.D.)--The Florida State University, 1986.
160

Models and validation measurements of bidirectional reflectance factor for diffuse reflecting materials

Walker, Joe Alan, 1945- January 1998 (has links)
A physical model developed from scattering theory by Hapke was applied to bidirectional reflectance factor (BRF) measurement data for several diffuse reflecting materials. All of the material samples were some form of polytetrafluoroethelyne (PTFE) powder. The solar illuminated diffuser for the Moderate Resolution Imaging Spectroradiometer (MODIS) was one of the samples. The BRF was characterized in seven wavelength bands, covering a spectral range of 400 nm to 2100 nm. The BRFs were determined, using the Santa Barbara Remote Sensing (SBRS) scattering goniopolarimeter, by measuring all four linear polarization components and using those measurements in the BRF equations of Clarke. The scattering goniopolarimeter was carefully characterized in a series of measurements. It was calibrated by comparing BRF measurements to the BRF calibration values of a reflectance standard. A detailed error analysis was done. The uncertainties for each of the four polarization components was considered individually, and then combined to obtain the total estimated uncertainty in the BRF values. The mean-square errors of the measured BRF sample averages were compared to the estimated uncertainties. Results of BRF evaluations and the measurement uncertainties for the different diffusers are presented. A study of several variations of the Hapke scattering model was made. The models were successfully applied to each of the four polarization components of BRF, in addition to the unpolarized BRF. The quality of the models was evaluated using the "root-mean-square of the fit" merit function, RMSf The simplest Hapke model gave RMSf values from two percent down to less than one percent, but the vegetation canopy form of the Hapke model gave higher RMSf values, from six to ten percent. The Henyey-Greenstein single scattering phase function, even when used in the simplest Hapke model, gave RMSf values between two and eight percent, whereas Legendre polynomial phase functions resulted in RMSf values of less than one percent. Equations with an additional forward scatter term usually made a slight improvement, on the order of one to two tenths of a percent. To obtain a representative model, at least two sets of BRF data at different incidence angles were needed.

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