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1.
Grim, Joel Q.
EXPERIMENTAL AND COMPUTATIONAL STUDIES OF NONLINEAR QUENCHING IN MATERIALS USED AS RADIATION DETECTORS.
Degree: 2012, Wake Forest University
URL: http://hdl.handle.net/10339/37441
► The next generation of radiation detectors used in security scanning, medical imaging, and high energy physics applications depend on understanding the physical mechanisms that limit…
(more)
▼ The next generation of radiation detectors used in security scanning, medical imaging, and high energy physics applications depend on understanding the physical mechanisms that limit intrinsic energy resolution. Nonproportionality between electron energy response and the initial energy of a stopping electron is a significant cause of the degradation of energy resolution. The physical origin of nonproportional response is generally regarded to start with nonlinear quenching, proportional to 2nd or 3rd power of local excitation density. A large part of the present work is the experimental determination of the important physical parameters governing nonproportional response. To that end, both the magnitude and kinetic order of nonlinear quenching rates have been determined using an above-gap z-scan technique in materials ranging from halides such as CsI:Tl and SrI2:Eu, to oxides and semiconductors. It is shown that the kinetic order of nonlinear quenching has direct consequences on scintillator light yield and proportionality. Furthermore, 2nd order quenching indicates the carrier population is dominated by bound electrons and holes (excitons or self-trapped excitons), and 3rd order quenching implies free carriers. A population of free carriers or bound electrons and holes has consequences beyond the difference in light yield and proportionality that result from pure 2nd or 3rd order quenching. For example, in halides with self-trapped holes, the mobile electrons can move away from the dense core of holes thus escaping nonlinear quenching. Coupled with calculations of hot electron group velocity, we have used this information to explain why NaI:Tl and SrI2:Eu have better proportionality and light yield than oxides and flourides, as well as why SrI2:Eu has better light yield and proportionality than NaI:Tl.
Subjects/Keywords: Geant4
…Monte Carlo electron cascade simulations using Geant4.
Calculated
electron response for… …of energy
deposition were conducted using Geant4 with the low-energy electromagnetic… …coincidence
and K-dip. An example of the Geant4 electron cascade simulation is shown in Fig. 5 for… …using Geant4. Ten different tracks
with initial electron energy of 150 keV are shown.
In…
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APA (6th Edition):
Grim, J. Q. (2012). EXPERIMENTAL AND COMPUTATIONAL STUDIES OF NONLINEAR QUENCHING IN MATERIALS USED AS RADIATION DETECTORS. (Thesis). Wake Forest University. Retrieved from http://hdl.handle.net/10339/37441
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Grim, Joel Q. “EXPERIMENTAL AND COMPUTATIONAL STUDIES OF NONLINEAR QUENCHING IN MATERIALS USED AS RADIATION DETECTORS.” 2012. Thesis, Wake Forest University. Accessed March 04, 2021.
http://hdl.handle.net/10339/37441.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Grim, Joel Q. “EXPERIMENTAL AND COMPUTATIONAL STUDIES OF NONLINEAR QUENCHING IN MATERIALS USED AS RADIATION DETECTORS.” 2012. Web. 04 Mar 2021.
Vancouver:
Grim JQ. EXPERIMENTAL AND COMPUTATIONAL STUDIES OF NONLINEAR QUENCHING IN MATERIALS USED AS RADIATION DETECTORS. [Internet] [Thesis]. Wake Forest University; 2012. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10339/37441.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Grim JQ. EXPERIMENTAL AND COMPUTATIONAL STUDIES OF NONLINEAR QUENCHING IN MATERIALS USED AS RADIATION DETECTORS. [Thesis]. Wake Forest University; 2012. Available from: http://hdl.handle.net/10339/37441
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Queens University
2.
Liu, Shuo.
The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB
.
Degree: Physics, Engineering Physics and Astronomy, 2011, Queens University
URL: http://hdl.handle.net/1974/6298
► SuperCDMS is the next generation of the Cryogenic Dark Matter Search experiment (CDMS), aimed at the detection of the Weakly Interacting dark matter Particles (WIMPs)…
(more)
▼ SuperCDMS is the next generation of the Cryogenic Dark Matter Search experiment (CDMS), aimed at the detection of the Weakly Interacting dark matter Particles (WIMPs) with the use of phonon and ionization signals in germanium detectors operated at about 40 mK. The current experiment is operating in the Soudan underground laboratory in northern Minnesota. However, due to limitation of cosmic ray muons, in the next stage of SuperCDMS, the whole experiment will be moved to a deeper site at SNOLAB. This could reduce the influence of extraterrestrial high energy particles to a negligible level, leaving the natural radioactivity locally existing in the laboratory wall rock as the dominating background source. Along with this relocation, newly designed detectors will be implemented to further increase the sensitivity. The prototype of this kind of detector has been manufactured, but it needs to be carefully tested prior to its formal application. To thoroughly examine its performance, especially in an environment that is less affected by cosmic rays, a new detector testing facility is to be built underground at SNOLAB (STF) surrounded by a water tank serving as the passive shield against the natural radioactivity. A series of Monte Carlo simulations have been performed to investigate the effectiveness of the water tank shield, the background level and also the energy spectra of events in the detectors. The goal of 1 neutron/day and 1 Hz of gammas for external sources can be achieved.
Subjects/Keywords: GEANT4
;
STF
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APA (6th Edition):
Liu, S. (2011). The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB
. (Thesis). Queens University. Retrieved from http://hdl.handle.net/1974/6298
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Liu, Shuo. “The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB
.” 2011. Thesis, Queens University. Accessed March 04, 2021.
http://hdl.handle.net/1974/6298.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Liu, Shuo. “The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB
.” 2011. Web. 04 Mar 2021.
Vancouver:
Liu S. The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB
. [Internet] [Thesis]. Queens University; 2011. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1974/6298.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Liu S. The Limiting Background in a Detector Testing Facility for SuperCDMS at SNOLAB
. [Thesis]. Queens University; 2011. Available from: http://hdl.handle.net/1974/6298
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Utah
3.
van den akker, Mary Evelyn.
A macroscopic and microscopic study of radon exposure using geant4 and mcnpx to estimate dose rates and dna damage.
Degree: MSin Nuclear Engineering, Civil & Environmental Engineering, 2015, University of Utah
URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3975/rec/49
► Radon is considered the second-leading cause of lung cancer after smoking. Epidemiological studies have been conducted in miner cohorts as well as general populations to…
(more)
▼ Radon is considered the second-leading cause of lung cancer after smoking. Epidemiological studies have been conducted in miner cohorts as well as general populations to estimate the risks associated with high and low dose exposures. There are problems with extrapolating risk estimates to low dose exposures, mainly that the dose-response curve at low doses is not well understood. Calculated dosimetric quantities give average energy depositions in an organ or a whole body, but morphological features of an individual can affect these values. As opposed to human phantom models, Computed Tomography (CT) scans provide unique, patient-specific geometries that are valuable in modeling the radiological effects of the short-lived radon progeny sources. Monte Carlo particle transport code Geant4 was used with the CT scan data to model radon inhalation in the main bronchial bifurcation. The equivalent dose rates are near the lower bounds of estimates found in the literature, depending on source volume. To complement the macroscopic study, simulations were run in a small tissue volume in Geant4-DNA toolkit. As an expansion of Geant4 meant to simulate direct physical interactions at the cellular level, the particle track structure of the radon progeny alphas can be analyzed to estimate the damage that can occur in sensitive cellular structures like the DNA molecule. These estimates of DNA double strand breaks are lower than those found in Geant4-DNA studies. Further refinements of the microscopic model are at the cutting edge of nanodosimetry research.
Subjects/Keywords: Dosimetry; Geant4; Radon
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APA ·
Chicago ·
MLA ·
Vancouver ·
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to Zotero / EndNote / Reference
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APA (6th Edition):
van den akker, M. E. (2015). A macroscopic and microscopic study of radon exposure using geant4 and mcnpx to estimate dose rates and dna damage. (Masters Thesis). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3975/rec/49
Chicago Manual of Style (16th Edition):
van den akker, Mary Evelyn. “A macroscopic and microscopic study of radon exposure using geant4 and mcnpx to estimate dose rates and dna damage.” 2015. Masters Thesis, University of Utah. Accessed March 04, 2021.
http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3975/rec/49.
MLA Handbook (7th Edition):
van den akker, Mary Evelyn. “A macroscopic and microscopic study of radon exposure using geant4 and mcnpx to estimate dose rates and dna damage.” 2015. Web. 04 Mar 2021.
Vancouver:
van den akker ME. A macroscopic and microscopic study of radon exposure using geant4 and mcnpx to estimate dose rates and dna damage. [Internet] [Masters thesis]. University of Utah; 2015. [cited 2021 Mar 04].
Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3975/rec/49.
Council of Science Editors:
van den akker ME. A macroscopic and microscopic study of radon exposure using geant4 and mcnpx to estimate dose rates and dna damage. [Masters Thesis]. University of Utah; 2015. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/3975/rec/49

University of Utah
4.
Lund, Matthew Lawrence.
High-performing simulations of the space radiation environment for the international space station and apollo missions.
Degree: MSin Nuclear Engineering, Civil & Environmental Engineering, 2016, University of Utah
URL: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/4081/rec/1229
► The space radiation environment is a significant challenge to future manned and unmanned space travels. Future missions will rely more on accurate simulations of radiation…
(more)
▼ The space radiation environment is a significant challenge to future manned and unmanned space travels. Future missions will rely more on accurate simulations of radiation transport in space through spacecraft to predict astronaut dose and energy deposition within spacecraft electronics. The International Space Station provides long-term measurements of the radiation environment in Low Earth Orbit (LEO); however, only the Apollo missions provided dosimetry data beyond LEO. Thus dosimetry analysis for deep space missions is poorly supported with currently available data, and there is a need to develop dosimetry-predicting models for extended deep space missions. GEANT4, a Monte Carlo Method, provides a powerful toolkit in C++ for simulation of radiation transport in arbitrary media, thus including the spacecraft and space travels. The newest version of GEANT4 supports multithreading and MPI, resulting in faster distributive processing of simula- tions in high-performance computing clusters. This thesis introduces a new application based on GEANT4 that greatly reduces computational time using Kingspeak and Ember computational clus- ters at the Center for High Performance Computing (CHPC) to simulate radiation transport through full spacecraft geometry, reducing simulation time to hours instead of weeks without post simula- tion processing. Additionally, this thesis introduces a new set of detectors besides the historically used International Commission of Radiation Units (ICRU) spheres for calculating dose distribution, including a Thermoluminescent Detector (TLD), Tissue Equivalent Proportional Counter (TEPC), and human phantom combined with a series of new primitive scorers in GEANT4 to calculate dose equivalence based on the International Commission of Radiation Protection (ICRP) standards. The developed models in this thesis predict dose depositions in the International Space Station and during the Apollo missions showing good agreement with experimental measurements. From these models the greatest contributor to radiation dose for the Apollo missions was from Galactic Cosmic Rays due to the short time within the radiation belts. The Apollo 14 dose measurements were an order of magnitude higher compared to other Apollo missions. The GEANT4 model of the Apollo Command Module shows consistent doses due to Galactic Cosmic Rays and Radiation Belts for all missions, with a small variation in dose distribution across the capsule. The model also predicts well the dose depositions and equivalent dose values in various human organs for the International Space Station or Apollo Command Module.
Subjects/Keywords: Apollo; GEANT4; ISS; radiation; shielding
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lund, M. L. (2016). High-performing simulations of the space radiation environment for the international space station and apollo missions. (Masters Thesis). University of Utah. Retrieved from http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/4081/rec/1229
Chicago Manual of Style (16th Edition):
Lund, Matthew Lawrence. “High-performing simulations of the space radiation environment for the international space station and apollo missions.” 2016. Masters Thesis, University of Utah. Accessed March 04, 2021.
http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/4081/rec/1229.
MLA Handbook (7th Edition):
Lund, Matthew Lawrence. “High-performing simulations of the space radiation environment for the international space station and apollo missions.” 2016. Web. 04 Mar 2021.
Vancouver:
Lund ML. High-performing simulations of the space radiation environment for the international space station and apollo missions. [Internet] [Masters thesis]. University of Utah; 2016. [cited 2021 Mar 04].
Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/4081/rec/1229.
Council of Science Editors:
Lund ML. High-performing simulations of the space radiation environment for the international space station and apollo missions. [Masters Thesis]. University of Utah; 2016. Available from: http://content.lib.utah.edu/cdm/singleitem/collection/etd3/id/4081/rec/1229

Texas A&M University
5.
Guan, Fada 1982-.
Application of Dynamic Monte Carlo Technique in Proton Beam Radiotherapy using Geant4 Simulation Toolkit.
Degree: PhD, Nuclear Engineering, 2012, Texas A&M University
URL: http://hdl.handle.net/1969.1/149220
► Monte Carlo method has been successfully applied in simulating the particles transport problems. Most of the Monte Carlo simulation tools are static and they can…
(more)
▼ Monte Carlo method has been successfully applied in simulating the particles transport problems. Most of the Monte Carlo simulation tools are static and they can only be used to perform the static simulations for the problems with fixed physics and geometry settings. Proton therapy is a dynamic treatment technique in the clinical application. In this research, we developed a method to perform the dynamic Monte Carlo simulation of proton therapy using
Geant4 simulation toolkit. A passive-scattering treatment nozzle equipped with a rotating range modulation wheel was modeled in this research.
One important application of the Monte Carlo simulation is to predict the spatial dose distribution in the target geometry. For simplification, a mathematical model of a human body is usually used as the target, but only the average dose over the whole organ or tissue can be obtained rather than the accurate spatial dose distribution. In this research, we developed a method using MATLAB to convert the medical images of a patient from CT scanning into the patient voxel geometry. Hence, if the patient voxel geometry is used as the target in the Monte Carlo simulation, the accurate spatial dose distribution in the target can be obtained.
A data analysis tool?root was used to score the simulation results during a
Geant4 simulation and to analyze the data and plot results after simulation.
Finally, we successfully obtained the accurate spatial dose distribution in part of a human body after treating a patient with prostate cancer using proton therapy.
Advisors/Committee Members: Poston, John W (advisor), Braby, Leslie A (committee member), Ford, John R (committee member), Turner, Nancy D (committee member).
Subjects/Keywords: Geant4; Proton Therapy; Monte Carlo
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APA ·
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MLA ·
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APA (6th Edition):
Guan, F. 1. (2012). Application of Dynamic Monte Carlo Technique in Proton Beam Radiotherapy using Geant4 Simulation Toolkit. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/149220
Chicago Manual of Style (16th Edition):
Guan, Fada 1982-. “Application of Dynamic Monte Carlo Technique in Proton Beam Radiotherapy using Geant4 Simulation Toolkit.” 2012. Doctoral Dissertation, Texas A&M University. Accessed March 04, 2021.
http://hdl.handle.net/1969.1/149220.
MLA Handbook (7th Edition):
Guan, Fada 1982-. “Application of Dynamic Monte Carlo Technique in Proton Beam Radiotherapy using Geant4 Simulation Toolkit.” 2012. Web. 04 Mar 2021.
Vancouver:
Guan F1. Application of Dynamic Monte Carlo Technique in Proton Beam Radiotherapy using Geant4 Simulation Toolkit. [Internet] [Doctoral dissertation]. Texas A&M University; 2012. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/1969.1/149220.
Council of Science Editors:
Guan F1. Application of Dynamic Monte Carlo Technique in Proton Beam Radiotherapy using Geant4 Simulation Toolkit. [Doctoral Dissertation]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/149220

McMaster University
6.
Ford, Wesley.
Benchmarking of G4STORK for the Coolant Void Reactivity of the Super Critical Water Reactor Design.
Degree: MASc, 2016, McMaster University
URL: http://hdl.handle.net/11375/20027
► The objectives of this thesis were the validation of G4STORK to use it for the investigation of the SCWR lattice cell. MCNP6 was chosen as…
(more)
▼ The objectives of this thesis were the validation of G4STORK to use it for the investigation of the SCWR lattice cell. MCNP6 was chosen as the program that the methodology of G4STORK would be validated against. Over multiple steps, the methodology of G4STORK was matched to that of MCNP6 (described here, 3.4). After each step, the output of the two programs were compared, allowing us to pinpoint why and where discrepancies came about. At the end of this process, we were able to show that when G4STORK used the same assumptions as MCNP6, it produced similar results (shown here, 4.1.4). The results of G4STORK simulating the SCWR lattice cell, using its more accurate default methodology, was then compared to those of MCNP6 (shown here, 4.2.1). Large differences in the results were seen to occur, because of the inaccurate assumptions used by MCNP6, during transient cases. We concluded that despite the existence of minor discrepancies between the results of MCNP and G4STORK for some cases, G4STORK is still the theoretically more accurate method for simulating lattice cell cases such as these, due to MCNP’s use of the generational method.
Thesis
Master of Applied Science (MASc)
Advisors/Committee Members: Buijs, Adriaan, Nuclear Engineering.
Subjects/Keywords: SCWR MCNP GEANT4 G4STORK Benchmark
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ford, W. (2016). Benchmarking of G4STORK for the Coolant Void Reactivity of the Super Critical Water Reactor Design. (Masters Thesis). McMaster University. Retrieved from http://hdl.handle.net/11375/20027
Chicago Manual of Style (16th Edition):
Ford, Wesley. “Benchmarking of G4STORK for the Coolant Void Reactivity of the Super Critical Water Reactor Design.” 2016. Masters Thesis, McMaster University. Accessed March 04, 2021.
http://hdl.handle.net/11375/20027.
MLA Handbook (7th Edition):
Ford, Wesley. “Benchmarking of G4STORK for the Coolant Void Reactivity of the Super Critical Water Reactor Design.” 2016. Web. 04 Mar 2021.
Vancouver:
Ford W. Benchmarking of G4STORK for the Coolant Void Reactivity of the Super Critical Water Reactor Design. [Internet] [Masters thesis]. McMaster University; 2016. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/11375/20027.
Council of Science Editors:
Ford W. Benchmarking of G4STORK for the Coolant Void Reactivity of the Super Critical Water Reactor Design. [Masters Thesis]. McMaster University; 2016. Available from: http://hdl.handle.net/11375/20027

University of Wollongong
7.
Pope, Dane.
The dosimetric effect of prostatic calcifications on Low Dose Rate (LDR) brachytherapy.
Degree: MS- Research, 2013, University of Wollongong
URL: ;
https://ro.uow.edu.au/theses/3887
► Low Dose Rate brachytherapy is a widely used procedure in Australia and in the world to cure prostate cancer. Commercial Treatment Planning System (TPS)…
(more)
▼ Low Dose Rate brachytherapy is a widely used procedure in Australia and in the world to cure prostate cancer. Commercial Treatment Planning System (TPS) used in every day clinical practice approximates all tissues to water, neglecting the existence of calcifications. However, their presence in the prostate may perturb the dose because of their higher photoelectric effect cross section in comparison to water.
This study addresses quantitatively the effect of prostatic calcification in the clinical outcome of brachytherapy treatment, through of experimental measurements and Monte Carlo simulations.
Four pathological calcification samples were characterised with µ-PIXE to determine their heavy elemental composition. Spectral analysis detected eight elements with atomic number greater than 13. It was discovered that calcium, phosphorus and zinc were the most predominant heavy elements in the calcification composition.
The dosimetric effect of the four calcification samples was studied experimentally. Each calcification was embedded in a PMMA phantom and located between a closely placed I-125 brachytherapy seed and a MOSkinTMdetector. Dose rate reductions between 3.41% and 40.12% were observed.
Geant4 based simulations were used to evaluate quantitatively the dosimetric effect of calcifications. Four real patient brachytherapy treatments were modelled in the simulation experimental set-up, in terms of distribution of brachytherapy seeds and calcifications in the prostate. Different calcification compositions were modelled.
Dose reductions were observed to be around 7-20% and 20-30% for small and average sized calculi, respectively. Single large calcifications and closely placed calculi caused dose reductions between 30-60%. It was also found that calculi smaller than 0.5mm in diameter have a negligible dosimetric impact.
The simulation study showed a varying reduction on dosimetric parameters when a hydroxyapatite composition was adopted to model the patients’ calcifications. It was calculated that the parameter D90 was reduced by 2-3% regardless of calcification surface area and volume. The parameters V100, V150 and V200 were reduced by as much as 2.5% and on average by 1%. These reductions were also found to relate to the surface area and volume of calcifications.
This work shows that calcifications can have a statistically significant impact on the clinical outcome of brachytherapy treatment. Such impact depends strongly on specific factors in the patient anatomy and treatment. These factors include the brachytherapy seeds distribution, the number, size, composition and spatial distribution of calcifications in the prostate.
Subjects/Keywords: LDR brachytherapy; calcifications; prostate; Geant4
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Pope, D. (2013). The dosimetric effect of prostatic calcifications on Low Dose Rate (LDR) brachytherapy. (Masters Thesis). University of Wollongong. Retrieved from ; https://ro.uow.edu.au/theses/3887
Chicago Manual of Style (16th Edition):
Pope, Dane. “The dosimetric effect of prostatic calcifications on Low Dose Rate (LDR) brachytherapy.” 2013. Masters Thesis, University of Wollongong. Accessed March 04, 2021.
; https://ro.uow.edu.au/theses/3887.
MLA Handbook (7th Edition):
Pope, Dane. “The dosimetric effect of prostatic calcifications on Low Dose Rate (LDR) brachytherapy.” 2013. Web. 04 Mar 2021.
Vancouver:
Pope D. The dosimetric effect of prostatic calcifications on Low Dose Rate (LDR) brachytherapy. [Internet] [Masters thesis]. University of Wollongong; 2013. [cited 2021 Mar 04].
Available from: ; https://ro.uow.edu.au/theses/3887.
Council of Science Editors:
Pope D. The dosimetric effect of prostatic calcifications on Low Dose Rate (LDR) brachytherapy. [Masters Thesis]. University of Wollongong; 2013. Available from: ; https://ro.uow.edu.au/theses/3887

University of Wollongong
8.
Peter Lazarakis, Peter.
Assessment of Monte Carlo approaches to nanodosimetry.
Degree: PhD, 2016, University of Wollongong
URL: ;
https://ro.uow.edu.au/theses/4658
Though Nanodosimetry is a relatively new field it is rapidly developing into a potentially important tool in the fields of radiation protection and radiobiology. This thesis focused on an investigation into the use of Monte Carlo tools for Nanodosimetric based studies.
Subjects/Keywords: Nanodosimetry; Monte Carlo; Geant4
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Peter Lazarakis, P. (2016). Assessment of Monte Carlo approaches to nanodosimetry. (Doctoral Dissertation). University of Wollongong. Retrieved from ; https://ro.uow.edu.au/theses/4658
Chicago Manual of Style (16th Edition):
Peter Lazarakis, Peter. “Assessment of Monte Carlo approaches to nanodosimetry.” 2016. Doctoral Dissertation, University of Wollongong. Accessed March 04, 2021.
; https://ro.uow.edu.au/theses/4658.
MLA Handbook (7th Edition):
Peter Lazarakis, Peter. “Assessment of Monte Carlo approaches to nanodosimetry.” 2016. Web. 04 Mar 2021.
Vancouver:
Peter Lazarakis P. Assessment of Monte Carlo approaches to nanodosimetry. [Internet] [Doctoral dissertation]. University of Wollongong; 2016. [cited 2021 Mar 04].
Available from: ; https://ro.uow.edu.au/theses/4658.
Council of Science Editors:
Peter Lazarakis P. Assessment of Monte Carlo approaches to nanodosimetry. [Doctoral Dissertation]. University of Wollongong; 2016. Available from: ; https://ro.uow.edu.au/theses/4658
9.
ANDRADE, Wellington Gomes de.
Experimento computacional para produção de feixes neutrônicos monoenergéticos gerados a partir de prótons de um acelerador tipo cíclotron
.
Degree: 2018, Universidade Federal de Pernambuco
URL: https://repositorio.ufpe.br/handle/123456789/30327
► Aceleradores tipo cíclotron são capazes de acelerar prótons até 18 MeV e dêuterons até 9 MeV. Estes aceleradores são utilizados para a produção de radiofármacos,…
(more)
▼ Aceleradores tipo cíclotron são capazes de acelerar prótons até 18 MeV e dêuterons até 9 MeV. Estes aceleradores são utilizados para a produção de radiofármacos, porém alguns possuem um canal experimental voltado à pesquisa. Diante disso, foi de interesse desse trabalho o estudo da viabilidade de implementação do feixe neutrônico a partir desse canal experimental, visto que demais fontes geradoras de nêutrons não são capazes de fornecer um fluxo contínuo e uniforme de nêutrons. Logo, foi realizado uma simulação computacional com o código
GEANT4 versão 10.0.1.p03 utilizando como dados características desse acelerador; feixe primário de prótons, energia em MeV e adotado como alvo o Berílio-9, o qual possui uma espessura de 2,5 mm. Os nêutrons gerados foram medidos a uma distância de 50 cm e sob os ângulos de 0º, 15º, 30º, 45º, 60º, 70º e 90º em relação ao feixe incidente. O exemplo foi baseado em estudos experimentais e validado através do método estatístico T pareado como descrito em literatura. Dessa forma, este trabalho resultou na afirmação de que é possível implementar um feixe neutrônico monoenergético a partir de um canal experimental do acelerador cíclotron.
Advisors/Committee Members: LIMA, Fernando Roberto de Andrade (advisor), VILELA, Eudice Correia (advisor), http://lattes.cnpq.br/9870663748100803 (advisor).
Subjects/Keywords: Ciclotron;
GEANT4;
Nêutrons monoenergéticos
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
ANDRADE, W. G. d. (2018). Experimento computacional para produção de feixes neutrônicos monoenergéticos gerados a partir de prótons de um acelerador tipo cíclotron
. (Doctoral Dissertation). Universidade Federal de Pernambuco. Retrieved from https://repositorio.ufpe.br/handle/123456789/30327
Chicago Manual of Style (16th Edition):
ANDRADE, Wellington Gomes de. “Experimento computacional para produção de feixes neutrônicos monoenergéticos gerados a partir de prótons de um acelerador tipo cíclotron
.” 2018. Doctoral Dissertation, Universidade Federal de Pernambuco. Accessed March 04, 2021.
https://repositorio.ufpe.br/handle/123456789/30327.
MLA Handbook (7th Edition):
ANDRADE, Wellington Gomes de. “Experimento computacional para produção de feixes neutrônicos monoenergéticos gerados a partir de prótons de um acelerador tipo cíclotron
.” 2018. Web. 04 Mar 2021.
Vancouver:
ANDRADE WGd. Experimento computacional para produção de feixes neutrônicos monoenergéticos gerados a partir de prótons de um acelerador tipo cíclotron
. [Internet] [Doctoral dissertation]. Universidade Federal de Pernambuco; 2018. [cited 2021 Mar 04].
Available from: https://repositorio.ufpe.br/handle/123456789/30327.
Council of Science Editors:
ANDRADE WGd. Experimento computacional para produção de feixes neutrônicos monoenergéticos gerados a partir de prótons de um acelerador tipo cíclotron
. [Doctoral Dissertation]. Universidade Federal de Pernambuco; 2018. Available from: https://repositorio.ufpe.br/handle/123456789/30327

Luleå University of Technology
10.
Strand, Liselott.
Design of Particle Instrument for the Energization and Radiation in Geospace (ERG) Spacecraft.
Degree: 2013, Luleå University of Technology
URL: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-57074
► Geospace is the region of outer space near Earth, which includes the magnetosphere and the upper region of the atmosphere. It is a hazardous…
(more)
▼ Geospace is the region of outer space near Earth, which includes the magnetosphere and the upper region of the atmosphere. It is a hazardous environment that contains high energy particles and is strongly dependant on the space weather. Studies show a high correlation between satellite operational anomalies, such as deep dielectric charging, and large flux enhancement of relativistic electrons in the outer radiation belt. An astronaut is exposed to radiation through high energy protons and relativistic electrons during extravehicular activities since these kinds of particles can penetrate a space suit. Furthermore, high energy particles can penetrate and transmit through instrument walls and thereby contaminate measurements through secondary electrons detected as noise. In order to prevent these radiation-induced effects it is crucial to explore and study how the space weather affects the radiation environment in geospace. The Energization and Radiation in Geospace (ERG) project is currently under development in the Institute of Space and Astronautical Science (ISAS)/ Japan Aerospace Exploration Agency (JAXA) for the declining phase of solar cycle 24. The main objective of this mission is to understand the dynamics of the Earth’s radiation belts. The satellite will be launched into the inner magnetosphere in December 2015. A set of instruments to cover a wide energy range and measure both ions and electrons will be onboard. One of those instruments is the Low Energy Particle instrument for ions (LEP-i). It is very difficult to measure low energy particles (<tens of keV) inside the inner magnetosphere since high energy particles will contaminate the measurements and produce a high background noise level. Therefore it is of utmost importance that the instrument is sufficiently shielded, which lead to another challenge of minimizing the mass of the instrument housing during the design process. The purpose of this thesis has been to optimize the thickness of the LEP-i instrument housing, preferably to reduce the total mass of the original design. This has been done by evaluation of the noise count rate levels in the detector and the Total Ionization Dose (TID) of the electronics boards through numerical simulations. The simulations have been done in the software Geant4, which is a toolkit for accurate simulation of particle passage through matter. Both the LEP-i instrument geometry and the satellite structure with the other onboard instruments have been included in the computer model. The results of the simulations; the noise count rate and the TID, have been plotted over the corresponding decrement in mass that the decrease of a wall thickness represent. From the simulations it has been concluded that the total mass of the LEP-i instrument housing can be reduced by approximately 1.22 kg compared to the original housing design, through decrement of several housing walls. From a scientific point of view, an apogee altitude of at least 30 700 km for the ERG satellite, is necessary to successfully achieve the mission…
Subjects/Keywords: Technology; Partikelinstrument; Geant4; Teknik
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Strand, L. (2013). Design of Particle Instrument for the Energization and Radiation in Geospace (ERG) Spacecraft. (Thesis). Luleå University of Technology. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-57074
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Strand, Liselott. “Design of Particle Instrument for the Energization and Radiation in Geospace (ERG) Spacecraft.” 2013. Thesis, Luleå University of Technology. Accessed March 04, 2021.
http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-57074.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Strand, Liselott. “Design of Particle Instrument for the Energization and Radiation in Geospace (ERG) Spacecraft.” 2013. Web. 04 Mar 2021.
Vancouver:
Strand L. Design of Particle Instrument for the Energization and Radiation in Geospace (ERG) Spacecraft. [Internet] [Thesis]. Luleå University of Technology; 2013. [cited 2021 Mar 04].
Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-57074.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Strand L. Design of Particle Instrument for the Energization and Radiation in Geospace (ERG) Spacecraft. [Thesis]. Luleå University of Technology; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-57074
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Colorado School of Mines
11.
Grover, Hannah N.
Efficiency optimization of a HPGe clover array for implantation decay experiments at FRIB.
Degree: MS(M.S.), Physics, 2018, Colorado School of Mines
URL: http://hdl.handle.net/11124/172582
► The Facility for Rare Isotope Beams is a new state-of-the-art facility being built at Michigan State University in order to better understand the the fundamental…
(more)
▼ The Facility for Rare Isotope Beams is a new state-of-the-art facility being built at Michigan State University in order to better understand the the fundamental building blocks of the universe. The decay station group hopes to combine a clover style gamma ray detector array with a small, planar HPGe detector to study some of the most exotic nuclei. This project focused on ensuring that this combination would maintain or improve the photon efficiency of a clover style array on its own, as well as optimizing the size of the planar HPGe detectors in the center of the array configuration. The results from simulations done in
Geant4 show that the efficiency of this combination of detectors is higher than just a clover array, and even significantly high for low energy gamma rays. In addition, the optimum radius of the planar HPGe detectors is 3.5 cm when considering both the cost and efficiency for the total configuration.
Advisors/Committee Members: Leach, Kyle (advisor), Shafer, Jenifer C. (committee member), Sarazin, Frederic (committee member).
Subjects/Keywords: Geant4; GRIFFIN; FRIB; spectroscopy; GeDSSD
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Grover, H. N. (2018). Efficiency optimization of a HPGe clover array for implantation decay experiments at FRIB. (Masters Thesis). Colorado School of Mines. Retrieved from http://hdl.handle.net/11124/172582
Chicago Manual of Style (16th Edition):
Grover, Hannah N. “Efficiency optimization of a HPGe clover array for implantation decay experiments at FRIB.” 2018. Masters Thesis, Colorado School of Mines. Accessed March 04, 2021.
http://hdl.handle.net/11124/172582.
MLA Handbook (7th Edition):
Grover, Hannah N. “Efficiency optimization of a HPGe clover array for implantation decay experiments at FRIB.” 2018. Web. 04 Mar 2021.
Vancouver:
Grover HN. Efficiency optimization of a HPGe clover array for implantation decay experiments at FRIB. [Internet] [Masters thesis]. Colorado School of Mines; 2018. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/11124/172582.
Council of Science Editors:
Grover HN. Efficiency optimization of a HPGe clover array for implantation decay experiments at FRIB. [Masters Thesis]. Colorado School of Mines; 2018. Available from: http://hdl.handle.net/11124/172582

Delft University of Technology
12.
Reichert, Jules (author).
Asteroid Muon Tomography: A feasibility study on using galactic cosmic rays to map small Solar System body interiors.
Degree: 2021, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:409c0c23-f012-400c-93c2-d780d56ed6f0
► Asteroids and comets are thought to be the primordial remnants of our early Solar System, their interior structure and composition providing a snapshot of this…
(more)
▼ Asteroids and comets are thought to be the primordial remnants of our early Solar System, their interior structure and composition providing a snapshot of this turbulent era of planet formation. Thus far, everything we know of the internals of these small Solar System bodies has been inferred from surface observations and meteorite mineralogy. Evidence suggests however that their surface characteristics might not be representative of their interior features, due to effects like granular convection and space weathering. One proposed method to directly measure these features makes use of the already present galactic cosmic ray flux. Muons are created in collisions between the asteroid surface and these cosmic rays, their properties altered by the type and quantity of material traversed. By measuring the muon flux exiting the surface, the interior can be reconstructed. This thesis surveys the feasibility of muon tomography in space, with model creation and particle passage simulations.
Aerospace Engineering
Advisors/Committee Members: Menicucci, A. (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: muon; tomography; asteroid; interior; Geant4
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Reichert, J. (. (2021). Asteroid Muon Tomography: A feasibility study on using galactic cosmic rays to map small Solar System body interiors. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:409c0c23-f012-400c-93c2-d780d56ed6f0
Chicago Manual of Style (16th Edition):
Reichert, Jules (author). “Asteroid Muon Tomography: A feasibility study on using galactic cosmic rays to map small Solar System body interiors.” 2021. Masters Thesis, Delft University of Technology. Accessed March 04, 2021.
http://resolver.tudelft.nl/uuid:409c0c23-f012-400c-93c2-d780d56ed6f0.
MLA Handbook (7th Edition):
Reichert, Jules (author). “Asteroid Muon Tomography: A feasibility study on using galactic cosmic rays to map small Solar System body interiors.” 2021. Web. 04 Mar 2021.
Vancouver:
Reichert J(. Asteroid Muon Tomography: A feasibility study on using galactic cosmic rays to map small Solar System body interiors. [Internet] [Masters thesis]. Delft University of Technology; 2021. [cited 2021 Mar 04].
Available from: http://resolver.tudelft.nl/uuid:409c0c23-f012-400c-93c2-d780d56ed6f0.
Council of Science Editors:
Reichert J(. Asteroid Muon Tomography: A feasibility study on using galactic cosmic rays to map small Solar System body interiors. [Masters Thesis]. Delft University of Technology; 2021. Available from: http://resolver.tudelft.nl/uuid:409c0c23-f012-400c-93c2-d780d56ed6f0

Penn State University
13.
Logoglu, Faruk.
COATED MICRO-PARTICLES FOR IMPROVED NEUTRON DETECTION WITH 6LiF:ZnS(Ag).
Degree: 2019, Penn State University
URL: https://submit-etda.libraries.psu.edu/catalog/16479ful51
► The supply of 3He has diminished due to the increased use in homeland security, medicine and science applications over the years, which has raised the…
(more)
▼ The supply of 3He has diminished due to the increased use in homeland security, medicine and science applications over the years, which has raised the price of the isotope.[1] This fact led to research on alternative ways of neutron detection. One of those ways is to use 6LiF:ZnS(Ag) scintillation detectors with 6Li acting as a neutron converter and the ZnS as inorganic scintillator that converts the energy of ionizing radiation into light to be detected by photon detectors. The Li is highly enriched in 6Li to a minimum of 95% to increase the neutron capture probability and therefore the tritium and alpha particle production. [2] The Li comes with the chemical compound of LiF since the Li metal has highly reactive chemical properties.
The existing neutron detection technology employs mixing of 6LiF and ZnS(Ag) grains in an optically transparent binder which holds the mixture together. Although this detection approach works, it has some shortcomings such as opaqueness of ZnS to its own light, which limits the thickness of the detectors and clustering of grains of the same type. This effect results in deteriorated light production and light transport properties of the scintillator.
The proposed way to overcome these problems is to design a coated micro-particle detector that utilizes 6LiF coated with ZnS and the distribution of these particles throughout the active volume of the detector. MCNP6,
GEANT4 and custom Monte Carlo code have been used to optimize the 6LiF micro-particle radius.
GEANT4 has been used to optimize the ZnS coating thickness and the pitch, which is the distance between the two micro-particles. Moreover, the commercially available EJ-426 detectors were modeled in
GEANT4 using LiF and ZnS grains distributed throughout the detection medium which is between two clear polyester sheets and the simulation results were compared to the experimental results for model validation.
The optimal dimension for the LiF radius was found to be 19μm and the optimal ZnS thickness was found to be 1μm. The best detectors were found to have the dimensions of 60μm pitch, 0.6mm thickness and 80μm pitch, 1mm thickness, on the average performing 1.7 times better than the best performing existing technology. A code was written in
GEANT4 to simulate the randomly distributed particles with varying radii and thicknesses as well as position and shape to test the proposed technology.
Advisors/Committee Members: Marek Flaska, Thesis Advisor/Co-Advisor, Arthur Thompson Motta, Committee Member, Azaree Tresong Lintereur, Committee Member.
Subjects/Keywords: Coated micro-particles; 6LiF:ZnS(Ag); GEANT4; Optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Logoglu, F. (2019). COATED MICRO-PARTICLES FOR IMPROVED NEUTRON DETECTION WITH 6LiF:ZnS(Ag). (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/16479ful51
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Logoglu, Faruk. “COATED MICRO-PARTICLES FOR IMPROVED NEUTRON DETECTION WITH 6LiF:ZnS(Ag).” 2019. Thesis, Penn State University. Accessed March 04, 2021.
https://submit-etda.libraries.psu.edu/catalog/16479ful51.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Logoglu, Faruk. “COATED MICRO-PARTICLES FOR IMPROVED NEUTRON DETECTION WITH 6LiF:ZnS(Ag).” 2019. Web. 04 Mar 2021.
Vancouver:
Logoglu F. COATED MICRO-PARTICLES FOR IMPROVED NEUTRON DETECTION WITH 6LiF:ZnS(Ag). [Internet] [Thesis]. Penn State University; 2019. [cited 2021 Mar 04].
Available from: https://submit-etda.libraries.psu.edu/catalog/16479ful51.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Logoglu F. COATED MICRO-PARTICLES FOR IMPROVED NEUTRON DETECTION WITH 6LiF:ZnS(Ag). [Thesis]. Penn State University; 2019. Available from: https://submit-etda.libraries.psu.edu/catalog/16479ful51
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universidade Nova
14.
Lopes, Gonçalo Filipe Barros.
Implementação de um sistema para simulação por Monte Carlo da passagem de fotões através do olho humano mediante a utilização da plataforma GEANT4 – II.
Degree: 2012, Universidade Nova
URL: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/7705
► Dissertação para obtenção do Grau de Mestre em Engenharia Biomédica
O olho humano é constituído internamente por um tecido complexo e opticamente heterogéneo, a retina.…
(more)
▼ Dissertação para obtenção do Grau de Mestre em
Engenharia Biomédica
O olho humano é constituído internamente por um tecido complexo e opticamente heterogéneo, a retina. A retina capta os estímulos luminosos exteriores e converte-os em impulsos nervosos que dão origem à sensação visual. A Degeneração Macular Relacionada com a Idade (DMRI) é uma doença crónica e irreversível. Ela causa danos na retina por acumulação de materiais extracelulares, o que leva à perda da acuidade visual. Um dos sintomas mais comuns da DMRI é o aparecimento de drusas, nódulos irregulares de cor amarelada. Devido ao seu potencial irreversível é importante diagnosticar atempadamente para um tratamento precoce. Nesse sentido, construiu-se um modelo da retina através da plataforma GEANT4, que permitiu simular e analisar os fenómenos de dispersão provocados por essa doença. A plataforma GEANT4 possui bibliotecas de classes C++ e aplica métodos de Monte Carlo que possibilitam simular a propagação dos fotões no fundo ocular.
De modo a testar a validade da implementação efectuada, foi realizado um estudo dos valores de reflectância, transmitância e absorvância para comparação com outro método conhecido que descreve o transporte da luz em várias camadas de tecidos, Monte Carlo Modeling of Light Transport in Multi-layered Tissues (MCML). Concluiu-se que existe uma diferença significativa entre os valores previstos pelas duas implementações. É sugerida uma explicação para as referidas diferenças. Posteriormente, foi realizada uma avaliação com os valores de reflectância encontrados na literatura para o fundo ocular e retina. Essa avaliação validou a implementação efectuada no GEANT4 para o estudo do fundo ocular. Por fim, foram efectuados estudos que demonstraram que a distribuição espacial dos fotões é altamente dependente do livre percurso médio de dispersão do objecto em estudo, a drusa. Foram ainda realizadas simulações que pretenderam aproximar o estudo das condições reais a que um possível diagnóstico poderá estar sujeito. O trabalho efectuado forneceu dados importantes acerca da distribuição espacial dos fotões provocada pela doença que foi implementada, e trás alguma luz à forma como os fotões se propagam no fundo ocular.
Advisors/Committee Members: Vieira, Pedro, Santos, José Paulo.
Subjects/Keywords: GEANT4; Olho; Retina; Luz; Drusa; Reflectância
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lopes, G. F. B. (2012). Implementação de um sistema para simulação por Monte Carlo da passagem de fotões através do olho humano mediante a utilização da plataforma GEANT4 – II. (Thesis). Universidade Nova. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/7705
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Lopes, Gonçalo Filipe Barros. “Implementação de um sistema para simulação por Monte Carlo da passagem de fotões através do olho humano mediante a utilização da plataforma GEANT4 – II.” 2012. Thesis, Universidade Nova. Accessed March 04, 2021.
http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/7705.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Lopes, Gonçalo Filipe Barros. “Implementação de um sistema para simulação por Monte Carlo da passagem de fotões através do olho humano mediante a utilização da plataforma GEANT4 – II.” 2012. Web. 04 Mar 2021.
Vancouver:
Lopes GFB. Implementação de um sistema para simulação por Monte Carlo da passagem de fotões através do olho humano mediante a utilização da plataforma GEANT4 – II. [Internet] [Thesis]. Universidade Nova; 2012. [cited 2021 Mar 04].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/7705.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Lopes GFB. Implementação de um sistema para simulação por Monte Carlo da passagem de fotões através do olho humano mediante a utilização da plataforma GEANT4 – II. [Thesis]. Universidade Nova; 2012. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/7705
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
15.
Pham, Quang Trung.
Couplage et validation de l'extension GeantA-DNA dans la plateforme de simulation Monte Carlo GATE pour l'irradiation de molécules d'ADN dans un environnement de grille de calcul : Coupling and validation of the Geant4-DNA extension into the Gate Monte Carlo simulation platform for the irradiation of DNA molecules in a grid computing environment.
Degree: Docteur es, Physique Corpusculaire, 2014, Université Blaise-Pascale, Clermont-Ferrand II
URL: http://www.theses.fr/2014CLF22456
► Les méthodes de simulation Monte-Carlo s’étendent avec succès à différents domaines de la physique médicale mais aussi à différentes échelles, par exemple de la planification…
(more)
▼ Les méthodes de simulation Monte-Carlo s’étendent avec succès à différents domaines de la physique médicale mais aussi à différentes échelles, par exemple de la planification des traitements de radiothérapie jusqu’à une prévision des effets des rayonnements au niveau des cellules cancéreuses. La plateforme de simulation Monte-Carlo GATE, basée sur l’outil Geant4, propose des fonctionnalités dédiées aux simulations en physique médicale (médecine nucléaire et radiothérapie). Pour les applications en radiobiologie, les modèles physiques Geant4-DNA implémentés jusqu’à très basse énergie (eV) permettent d’estimer des quantités micro-dosimétriques d’intérêt. Dans le but d’implémenter une plateforme de simulation Monte-Carlo multi-échelles, nous nous sommes d’abord intéressés à la validation des modèles physiques de Geant4-DNA, puis à leur intégration dans la plateforme de simulation GATE et enfin à une validation de cette implémentation dans un contexte de radiothérapie et protonthérapie. De manière à valider les modèles physiques de Geant4-DNA, des points kernels de dose en électrons mono-énergétiques (de 10 keV à 100 keV) ont été simulés en utilisant les modèles physiques de Geant4 et de Geant4-DNA et ils ont comparés au code Monte-Carlo EGSnrc. Les parcours et pouvoirs d’arrêts des électrons (de 7,4 eV à 1 MeV) et des protons (de 1 keV à 100 MeV) calculés avec Geant4-DNA (processus et modèles préalablement intégrés dans GATE) ont ensuite été validés. Nous avons alors proposé de simuler avec la plateforme GATE l’impact de faisceaux cliniques et pré-cliniques sur l’ADN cellulaire. Nous avons ainsi modélisé un faisceau de protonthérapie de 193,1 MeV, un accélérateur linéaire en mode électrons de 6 MeV et un irradiateur RX de 250 kV. Ces simulations ont d’abord été validées en milieu aqueux par une comparaison de la dose macroscopique avec des mesures expérimentales. Les faisceaux ont ensuite été utilisés pour calculer, pour chacun d’entre eux, les fréquences de dépôts d’énergie à l’ADN. La molécule d’ADN a été simulée tout d’abord grâce à des cylindres équivalents en dimension à 10 paires de base (2 nm x 2 nm), équivalents à la taille d’un nucléosome (10 nm x 5 nm) et équivalents à la taille d’une fibre de chromatine (25 nm x 25 nm). Tous ces cylindres ont été placés aléatoirement dans un volume d’eau liquide (de rayon 500 nm). Nous avons ensuite reconstruit la molécule d’ADN dans Geant4 à partir de la lecture de fichiers PDB (Protein Data Bank) représentant douze paires de base de la molécule d’ADN et un dinucléosome (347 paires de base). Enfin, nous avons développé un outil permettant de corréler les positions de dépôts d’énergie directs dans l’eau liquide avec les coordonnées des paires de base de l’ADN, afin de calculer les nombres de cassures simple et double brin de l’ADN. Tous les calculs réalisés au cours de ce travail, ont été déployés sur l’Infrastructure de Grille Européenne ; des tests de performance sont proposés pour mesurer l’intérêt de ce type d’architecture pour les calculs Monte-Carlo.
The Monte Carlo…
Advisors/Committee Members: Incerti, Sébastien (thesis director).
Subjects/Keywords: Simulations Monte-Carlo; Geant4/Geant4-DNA/GATE; Radiobiologie; Faisceaux cliniques et préclinique; Monte Carlo simulations; Geant4/Geant4-DNA/GATE; Radiobiology; Clinical and preclinical beams
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APA (6th Edition):
Pham, Q. T. (2014). Couplage et validation de l'extension GeantA-DNA dans la plateforme de simulation Monte Carlo GATE pour l'irradiation de molécules d'ADN dans un environnement de grille de calcul : Coupling and validation of the Geant4-DNA extension into the Gate Monte Carlo simulation platform for the irradiation of DNA molecules in a grid computing environment. (Doctoral Dissertation). Université Blaise-Pascale, Clermont-Ferrand II. Retrieved from http://www.theses.fr/2014CLF22456
Chicago Manual of Style (16th Edition):
Pham, Quang Trung. “Couplage et validation de l'extension GeantA-DNA dans la plateforme de simulation Monte Carlo GATE pour l'irradiation de molécules d'ADN dans un environnement de grille de calcul : Coupling and validation of the Geant4-DNA extension into the Gate Monte Carlo simulation platform for the irradiation of DNA molecules in a grid computing environment.” 2014. Doctoral Dissertation, Université Blaise-Pascale, Clermont-Ferrand II. Accessed March 04, 2021.
http://www.theses.fr/2014CLF22456.
MLA Handbook (7th Edition):
Pham, Quang Trung. “Couplage et validation de l'extension GeantA-DNA dans la plateforme de simulation Monte Carlo GATE pour l'irradiation de molécules d'ADN dans un environnement de grille de calcul : Coupling and validation of the Geant4-DNA extension into the Gate Monte Carlo simulation platform for the irradiation of DNA molecules in a grid computing environment.” 2014. Web. 04 Mar 2021.
Vancouver:
Pham QT. Couplage et validation de l'extension GeantA-DNA dans la plateforme de simulation Monte Carlo GATE pour l'irradiation de molécules d'ADN dans un environnement de grille de calcul : Coupling and validation of the Geant4-DNA extension into the Gate Monte Carlo simulation platform for the irradiation of DNA molecules in a grid computing environment. [Internet] [Doctoral dissertation]. Université Blaise-Pascale, Clermont-Ferrand II; 2014. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2014CLF22456.
Council of Science Editors:
Pham QT. Couplage et validation de l'extension GeantA-DNA dans la plateforme de simulation Monte Carlo GATE pour l'irradiation de molécules d'ADN dans un environnement de grille de calcul : Coupling and validation of the Geant4-DNA extension into the Gate Monte Carlo simulation platform for the irradiation of DNA molecules in a grid computing environment. [Doctoral Dissertation]. Université Blaise-Pascale, Clermont-Ferrand II; 2014. Available from: http://www.theses.fr/2014CLF22456

University of Arizona
16.
Aguwa, Kasarachi.
Radiation Dose Study in Nuclear Medicine Using GATE
.
Degree: 2015, University of Arizona
URL: http://hdl.handle.net/10150/593601
► Dose as a result of radiation exposure is the notion generally used to disclose the imparted energy in a volume of tissue to a potential…
(more)
▼ Dose as a result of radiation exposure is the notion generally used to disclose the imparted energy in a volume of tissue to a potential biological effect. The basic unit defined by the international system of units (SI system) is the radiation absorbed dose, which is expressed as the mean imparted energy in a mass element of the tissue known as "gray" (Gy) or J/kg. The procedure for ascertaining the absorbed dose is complicated since it involves the radiation transport of numerous types of charged particles and coupled photon interactions. The most precise method is to perform a full 3D Monte Carlo simulation of the radiation transport. There are various Monte Carlo toolkits that have tool compartments for dose calculations and measurements. The dose studies in this thesis were performed using the
GEANT4 Application for Emission Tomography (GATE) software (Janet al., 2011) GATE simulation toolkit has been used extensively in the medical imaging community, due to the fact that it uses the full capabilities of
GEANT4. It also utilizes an easy to-learn GATE macro language, which is more accessible than learning the
GEANT4/C++ programming language. This work combines GATE with digital phantoms generated using the NCAT (NURBS-based cardiac-torso phantom) toolkit (Segars et al., 2004) to allow efficient and effective estimation of 3D radiation dose maps. The GATE simulation tool has developed into a beneficial tool for Monte Carlo simulations involving both radiotherapy and imaging experiments. This work will present an overview of absorbed dose of common radionuclides used in nuclear medicine and serve as a guide to a user who is setting up a GATE simulation for a PET and SPECT study.
Advisors/Committee Members: Kupinski, Matthew A (advisor), Kupinski, Matthew A. (committeemember), Barrett, Harrison H. (committeemember), Clarkson, Eric W. (committeemember).
Subjects/Keywords: Geant4;
Nuclear Medicine;
Radiation;
Optical Sciences;
GATE
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Aguwa, K. (2015). Radiation Dose Study in Nuclear Medicine Using GATE
. (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/593601
Chicago Manual of Style (16th Edition):
Aguwa, Kasarachi. “Radiation Dose Study in Nuclear Medicine Using GATE
.” 2015. Masters Thesis, University of Arizona. Accessed March 04, 2021.
http://hdl.handle.net/10150/593601.
MLA Handbook (7th Edition):
Aguwa, Kasarachi. “Radiation Dose Study in Nuclear Medicine Using GATE
.” 2015. Web. 04 Mar 2021.
Vancouver:
Aguwa K. Radiation Dose Study in Nuclear Medicine Using GATE
. [Internet] [Masters thesis]. University of Arizona; 2015. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10150/593601.
Council of Science Editors:
Aguwa K. Radiation Dose Study in Nuclear Medicine Using GATE
. [Masters Thesis]. University of Arizona; 2015. Available from: http://hdl.handle.net/10150/593601
17.
Tang, Nicolas.
Évaluation, à partir de modélisations nanodosimétriques, de l'influence de la compaction de la chromatine sur les effets radio-induits précoces et extension aux effets tardifs (réparation des dommages à l’ADN et mort cellulaire). : Evaluation, from nanodosimetric modeling, of the influence of chromatin compaction on early radiation-induced effects and extension to late effects (DNA damage repair and cell death).
Degree: Docteur es, Astrophysique, Plasmas, nucléaire, 2019, Bordeaux
URL: http://www.theses.fr/2019BORD0160
► Ce travail de thèse s'inscrit dans le cadre d'une recherche fondamentale visant à améliorer la compréhension des mécanismes d'interaction des rayonnements ionisants avec la matière…
(more)
▼ Ce travail de thèse s'inscrit dans le cadre d'une recherche fondamentale visant à améliorer la compréhension des mécanismes d'interaction des rayonnements ionisants avec la matière biologique en s’intéressant à la prédiction par simulations numériques des dommages précoces radio-induits à l’ADN. Dans un premier temps, une étude sur le rôle des différents niveaux de compaction de la chromatine (hétérochromatine et euchromatine) dans l’induction de ces premiers effets, à savoir les cassures de brins de l’ADN, est proposée. De nouveaux modèles géométriques réalistes de noyaux cellulaires intégrant la compaction de la chromatine ont donc été créés et utilisés dans une chaîne de calcul, basée sur le code Monte Carlo ouvert et généraliste Geant4 et son extension Geant4-DNA, permettant de simuler les étapes physique, physico-chimique et chimique menant aux cassures de brin. Les développements effectués dans cette thèse ont également permis d’étudier l’impact de plusieurs types de rayonnement (protons, alphas, photons) sur les dommages radio-induits. Les différents résultats ont été confrontés à des données expérimentales et en particulier à celles obtenues par l’équipe de radiobiologistes de l’IRSN. Enfin, une étude portant sur les effets plus tardifs comme la réparation de l’ADN et la mort cellulaire a été réalisée par l’utilisation conjointe de la chaîne de calcul et de certains modèles paramétriques issus de la littérature. Ainsi, les résultats obtenus dans cette thèse ont permis d’acquérir de nouvelles connaissances et de développer des outils de calcul qui seront bientôt disponibles en accès libre à la communauté scientifique afin de prédire des effets biologiques de plusieurs types de rayonnement dans la perspective d’améliorer les modèles de risque.
This thesis work is part of a fundamental research aimed at improving the understanding of the mechanisms of interaction of ionizing radiation with biological matter by focusing on the prediction of early radiation-induced DNA damage by numerical simulations. As a first step, a study on the role of the different levels of chromatin compaction (heterochromatin and euchromatin) in the induction of these early effects, namely DNA strand breaks, is proposed. New realistic geometric models of cell nuclei integrating chromatin compaction have therefore been created and used in a calculation chain, based on the open source and general purpose Monte Carlo code Geant4 and its extension Geant4-DNA, to simulate the physical, physico-chemical and chemical stages leading to strand breaks. Developments in this thesis have also allowed studying the impact of several types of radiation (protons, alphas, photons) on radiation-induced damage. The various results were compared with experimental data and in particular those obtained by the IRSN team of radiobiologists. Finally, a study on later effects such as DNA repair and cell death was carried out using both the calculation chain and some parametric models from the literature. Thus, the results obtained in this thesis have made it…
Advisors/Committee Members: Incerti, Sébastien (thesis director).
Subjects/Keywords: Geant4/Geant4-DNA; Hétérochromatine; Euchromatine; Dommages à l'ADN; Réparation de l'ADN; Survie cellulaire; Geant4/Geant4-DNA; Heterochromatin; Euchromatin; DNA damage; DNA repair; Cell survival
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tang, N. (2019). Évaluation, à partir de modélisations nanodosimétriques, de l'influence de la compaction de la chromatine sur les effets radio-induits précoces et extension aux effets tardifs (réparation des dommages à l’ADN et mort cellulaire). : Evaluation, from nanodosimetric modeling, of the influence of chromatin compaction on early radiation-induced effects and extension to late effects (DNA damage repair and cell death). (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2019BORD0160
Chicago Manual of Style (16th Edition):
Tang, Nicolas. “Évaluation, à partir de modélisations nanodosimétriques, de l'influence de la compaction de la chromatine sur les effets radio-induits précoces et extension aux effets tardifs (réparation des dommages à l’ADN et mort cellulaire). : Evaluation, from nanodosimetric modeling, of the influence of chromatin compaction on early radiation-induced effects and extension to late effects (DNA damage repair and cell death).” 2019. Doctoral Dissertation, Bordeaux. Accessed March 04, 2021.
http://www.theses.fr/2019BORD0160.
MLA Handbook (7th Edition):
Tang, Nicolas. “Évaluation, à partir de modélisations nanodosimétriques, de l'influence de la compaction de la chromatine sur les effets radio-induits précoces et extension aux effets tardifs (réparation des dommages à l’ADN et mort cellulaire). : Evaluation, from nanodosimetric modeling, of the influence of chromatin compaction on early radiation-induced effects and extension to late effects (DNA damage repair and cell death).” 2019. Web. 04 Mar 2021.
Vancouver:
Tang N. Évaluation, à partir de modélisations nanodosimétriques, de l'influence de la compaction de la chromatine sur les effets radio-induits précoces et extension aux effets tardifs (réparation des dommages à l’ADN et mort cellulaire). : Evaluation, from nanodosimetric modeling, of the influence of chromatin compaction on early radiation-induced effects and extension to late effects (DNA damage repair and cell death). [Internet] [Doctoral dissertation]. Bordeaux; 2019. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2019BORD0160.
Council of Science Editors:
Tang N. Évaluation, à partir de modélisations nanodosimétriques, de l'influence de la compaction de la chromatine sur les effets radio-induits précoces et extension aux effets tardifs (réparation des dommages à l’ADN et mort cellulaire). : Evaluation, from nanodosimetric modeling, of the influence of chromatin compaction on early radiation-induced effects and extension to late effects (DNA damage repair and cell death). [Doctoral Dissertation]. Bordeaux; 2019. Available from: http://www.theses.fr/2019BORD0160
18.
Manuel Antonio Castro Ávila.
Estudo computacional da concepção e do desempenho da câmera de raios X do experimento protoMIRAX.
Degree: 2011, Instituto Nacional de Pesquisas Espaciais
URL: http://urlib.net/sid.inpe.br/mtc-m19/2011/02.10.13.46
► A construção de instrumentos focalizadores de radiação eletromagnética de altas energias, acima de ∼15 keV, ainda é um grande desafio tecnológico devido aos limites impostos…
(more)
▼ A construção de instrumentos focalizadores de radiação eletromagnética de altas energias, acima de ∼15 keV, ainda é um grande desafio tecnológico devido aos limites impostos pela óptica geométrica. Recentemente lançado, o satélite NuSTAR da NASA deverá conseguir elevar esse patamar até aproximadamente 80 keV. No entanto, em raios it{X} duros e raios γ de baixa energia, o método mais adequado para se produzir imagens em astrofísica ainda é o de máscara codificada, amplamente utilizado em experimentos em balões e satélites. Embora não produza imagens com alta relação sinal/ruído, pois não há concentração de fótons oriundos das fontes, o método permite imageamento com boa resolução angular em amplos campos de visada. Neste trabalho, fazemos um estudo computacional para definir em detalhe a melhor configuração possível para a câmera de raios it{X} do experimento de balão estratosférico protoMIRAX, da Divisão de Astrofísica do INPE. O experimento consiste essencialmente de uma câmera imageadora que utiliza a técnica da máscara codificada para obter imagens do céu de 30 a 200 keV num campo de visada de 20° x 20° FWHM, utilizando detectores CdZnTe de última geração. Foram realizadas simulações utilizando o conceituado pacote Geant4 para prever o ruído de fundo a ser observado em voos de balão, gerado por diversos tipos de partículas e fótons. Para isso foi concebido um modelo de massa detalhado para a câmera e foi feito um estudo dos campos de radiação em altitudes de balão. O conhecimento da intensidade e do espectro de ruído de fundo é fundamental para se definir os melhores materiais a serem utilizados, a estrutura do sistema de blindagem lateral e inferior, e a fração aberta da máscara, além de serem parâmetros fundamentais para se estimar a sensibilidade do instrumento. Foram realizadas também simulações de Monte Carlo com o objetivo de se determinar os parâmetros ideais para a máscara codificada do protoMIRAX. A aplicação de um método iterativo de reconstrução mostrou-se útil para a obtenção de resoluções angulares superiores aos instrumentos convencionais quando o ruído de fundo é relativamente fraco. Essa técnica permite a construção de câmeras de máscara codificada com aberturas de tamanho significativamente menor do que a resolução espacial do plano detector, algo que nunca foi utilizado em astrofísica.
Building focusing instruments for high-energy electromagnetic radiation above ∼ 15 keV is still a major technological challenge due to the limitations imposed by geometric optics. NASA s recently launched NuSTAR satellite shall extend this limit to 80 keV. However, at hard it{X} rays and low energy γ rays, the coded mask imaging technique is still the most suitable one, and it is widely used in both balloon and satellite experiments. Even though coded-mask systems do not provide images with high signal-to-noise ratios due to the fact that there is no concentration of photons coming from the sources, the technique allows imaging with good angular resolution in wide fields of…
Advisors/Committee Members: Haroldo Fraga de Campos Velho, João Braga, Jorge Mejía Cabeza.
Subjects/Keywords: máscara codificada; métodos iterativos; Geant4; ruído de fundo; imageamento em raios X; coded mask; iterative methods; Geant4; background; X-ray imaging
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ávila, M. A. C. (2011). Estudo computacional da concepção e do desempenho da câmera de raios X do experimento protoMIRAX. (Thesis). Instituto Nacional de Pesquisas Espaciais. Retrieved from http://urlib.net/sid.inpe.br/mtc-m19/2011/02.10.13.46
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ávila, Manuel Antonio Castro. “Estudo computacional da concepção e do desempenho da câmera de raios X do experimento protoMIRAX.” 2011. Thesis, Instituto Nacional de Pesquisas Espaciais. Accessed March 04, 2021.
http://urlib.net/sid.inpe.br/mtc-m19/2011/02.10.13.46.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ávila, Manuel Antonio Castro. “Estudo computacional da concepção e do desempenho da câmera de raios X do experimento protoMIRAX.” 2011. Web. 04 Mar 2021.
Vancouver:
Ávila MAC. Estudo computacional da concepção e do desempenho da câmera de raios X do experimento protoMIRAX. [Internet] [Thesis]. Instituto Nacional de Pesquisas Espaciais; 2011. [cited 2021 Mar 04].
Available from: http://urlib.net/sid.inpe.br/mtc-m19/2011/02.10.13.46.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ávila MAC. Estudo computacional da concepção e do desempenho da câmera de raios X do experimento protoMIRAX. [Thesis]. Instituto Nacional de Pesquisas Espaciais; 2011. Available from: http://urlib.net/sid.inpe.br/mtc-m19/2011/02.10.13.46
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
19.
Guimarães, Carla da Costa.
Monitoração individual externa: experimentos e simulações com o método de Monte Carlo.
Degree: PhD, Física, 2005, University of São Paulo
URL: http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072009-185822/
;
► Neste trabalho avaliamos a possibilidade de aplicar técnicas de simulação utilizando o método de Monte Carlo em dosimetria de fótons na monitoração individual externa. Para…
(more)
▼ Neste trabalho avaliamos a possibilidade de aplicar técnicas de simulação utilizando o método de Monte Carlo em dosimetria de fótons na monitoração individual externa. Para isso, simulamos experimentos com monitores de radiação contendo detectores termoluminescentes, TLD-100 e CaF2:NaCl, empregando a ferramenta computacional GEANT4. Começamos desenvolvendo um método de simulação de feixes de radiação produzidos pela incidência de elétrons em um alvo de tungstênio e filtragem pela janela de berílio e filtros adicionais para obter a radiação de qualidade desejada. Este processo, usado para simular campos de radiação de um tubo de raios X, foi validado através da comparação de características dos espectros simulados com valores de referência estabelecidos em normas internacionais, sendo estas características a camada semi-redutora, também medida experimentalmente, a energia média e a resolução espectral. Na simulação dos monitores termoluminescentes foram introduzidas aproximações na modelagem do detector para possibilitar a comparação entre os resultados experimentais e teóricos. Uma delas foi na densidade do detector de CaF2:NaCl, acrescentando 6% de ar na sua composição, tendo em vista a diferença entre o valor calculado e o obtido através de medidas. Foi também introduzida a aproximação referente à auto-atenuação de luz no detector de CaF2:NaCl no processo de leitura, empregando o coeficiente de atenuação de luz de 2,20(25) mm-1. Determinamos os coeficientes de conversão cp, do kerma no ar para o equivalente de dose pessoal, em simuladores de paralelepípedo de polimetil metacrilato (PMMA) com água, irradiados com feixes de radiação X com espectro estreito e largo, recomendados em normas [ISO 4037-1], e com os feixes implantados no Laboratório de Dosimetria. Verificamos que a intensidade de radiação retro-espalhada por este simulador é similar àquela do simulador de paralelepípedo sólido de tecido-equivalente ICRU. Na prática, isto torna o simulador de PMMA repleto de água, que além de ser barato é fácil de construir, um bom substituto para o simulador ICRU. Uma análise detalhada dos resultados obtidos mostrou que a utilização da grandeza kerma no meio na avaliação dos coeficientes de conversão cp para profundidades da ordem ou menores que 0,07 mm não é boa para feixes de fótons com energia no intervalo de 200 a 1250 keV. Nesta região, deve-se calcular o coeficiente de conversão empregando a dose absorvida. Concluise que o GEANT4 é uma ferramenta adequada não só para simular os monitores termoluminescentes e os procedimentos empregados na rotina do Laboratório de Dosimetria, mas para auxiliar na interpretação de todos os resultados experimentais obtidos na monitoração individual externa, nem sempre previstos.
In this work, we have evaluated the possibility of applying the Monte Carlo simulation technique in photon dosimetry of external individual monitoring. The GEANT4 toolkit was employed to simulate experiments with radiation monitors containing TLD-100 and CaF2:NaCl thermoluminescent detectors. As a first step,…
Advisors/Committee Members: Okuno, Emico.
Subjects/Keywords: Dosimetria; Dosimetry; GEANT4; GEANT4; Individual monitoring; Monitoração Individual
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Guimarães, C. d. C. (2005). Monitoração individual externa: experimentos e simulações com o método de Monte Carlo. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072009-185822/ ;
Chicago Manual of Style (16th Edition):
Guimarães, Carla da Costa. “Monitoração individual externa: experimentos e simulações com o método de Monte Carlo.” 2005. Doctoral Dissertation, University of São Paulo. Accessed March 04, 2021.
http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072009-185822/ ;.
MLA Handbook (7th Edition):
Guimarães, Carla da Costa. “Monitoração individual externa: experimentos e simulações com o método de Monte Carlo.” 2005. Web. 04 Mar 2021.
Vancouver:
Guimarães CdC. Monitoração individual externa: experimentos e simulações com o método de Monte Carlo. [Internet] [Doctoral dissertation]. University of São Paulo; 2005. [cited 2021 Mar 04].
Available from: http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072009-185822/ ;.
Council of Science Editors:
Guimarães CdC. Monitoração individual externa: experimentos e simulações com o método de Monte Carlo. [Doctoral Dissertation]. University of São Paulo; 2005. Available from: http://www.teses.usp.br/teses/disponiveis/43/43134/tde-06072009-185822/ ;
20.
Béné, Samuel.
Imagerie tomograpbique d'un volcan à l'aide des muons atmosphériques : Tomographic imaging of volcanoes using atmospheric muons.
Degree: Docteur es, Physique Corpusculaire, 2016, Université Blaise-Pascale, Clermont-Ferrand II
URL: http://www.theses.fr/2016CLF22786
► Les muons atmosphériques sont des particules élémentaires créées lors de l’interaction des rayons cosmiques de haute énergie avec les atomes de la haute atmosphère. Leur…
(more)
▼ Les muons atmosphériques sont des particules élémentaires créées lors de l’interaction des rayons cosmiques de haute énergie avec les atomes de la haute atmosphère. Leur capacité à traverser de grandes quantités de matière et leur abondance au niveau du sol permet d’utiliser leur flux comme support à la radiographie de grands objets. Cette technique, la muographie, possède notamment comme sujet d’application possible l’étude de volcans. La collaboration Tomuvol, au sein de laquelle cette thèse s’est déroulée, vise à mettre au point un détecteur et les techniques d’analyse permettant la réalisation d’une telle mesure avec comme sujet d’étude un volcan auvergnat : le Puy de Dôme. Ce manuscrit présente les contributions à ce travail du point de vue instrumental tout d’abord, avec la calibration et l’optimisation des performances des chambres GRPC utilisées pour la mesure. Les performances du détecteur lors des diverses campagnes de prise de données qui se sont déroulées au pied du Puy de Dôme sont également résumées. Dans une deuxième partie, l’accent est porté sur l’analyse physique des données obtenues avec, dans un premier temps, la description des travaux de simulation Monte-Carlo mis en œuvre avec le logiciel GEANT4. Puis, une technique d’estimation du flux transmis de muons atmosphériques à l’aide d’une méthode de type noyaux est présentée, et la carte de densité estimée du Puy de Dôme qui en découle est comparée aux résultats issus de techniques géophysiques.
Atmospheric muons are elementary particles originating from the interaction of high energy cosmic rays with atoms in the upper atmosphere. Their ability to travel through a large amount of matter and their abundance at ground level allows for their flux to be used as a probe for the radiography of big objects. This technique, muography, can in particular be of interest for the study of volcanoes. The Tomuvol collaboration, within which this thesis took place, aims at developing a detector and analysis techniques allowing to perform such a measurment, using a volcano from Auvergne as a case study : the Puy de Dôme. This document describes the author’s contributions to this work, focusing on the intrumentation aspect first, with the calibration and optimisation of the GRPC chambers used to perform the measurment. The performances of the detector during the various campaigns of data acquisition at the base of the Puy de Dôme are also sumed up. A second part is dedicated to the physical analysis of the data with, firstly, the description of the Monte-Carlo simulations that were developed using the GEANT4 software. Then, a kernel-like estimation method of the transmitted flux of atmospheric muons is described, and the density map of the Puy de Dôme thus obtained is compared to results coming from geophysical techniques.
Advisors/Committee Members: Cârloganu, Cristina (thesis director).
Subjects/Keywords: Muographie; Volcan; Muons atmosphériques; GRPC; GEANT4; Estimation par noyaux; Muography; Volcano; Atmospheric muons; GRPC; GEANT4; Kernel estimation
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APA (6th Edition):
Béné, S. (2016). Imagerie tomograpbique d'un volcan à l'aide des muons atmosphériques : Tomographic imaging of volcanoes using atmospheric muons. (Doctoral Dissertation). Université Blaise-Pascale, Clermont-Ferrand II. Retrieved from http://www.theses.fr/2016CLF22786
Chicago Manual of Style (16th Edition):
Béné, Samuel. “Imagerie tomograpbique d'un volcan à l'aide des muons atmosphériques : Tomographic imaging of volcanoes using atmospheric muons.” 2016. Doctoral Dissertation, Université Blaise-Pascale, Clermont-Ferrand II. Accessed March 04, 2021.
http://www.theses.fr/2016CLF22786.
MLA Handbook (7th Edition):
Béné, Samuel. “Imagerie tomograpbique d'un volcan à l'aide des muons atmosphériques : Tomographic imaging of volcanoes using atmospheric muons.” 2016. Web. 04 Mar 2021.
Vancouver:
Béné S. Imagerie tomograpbique d'un volcan à l'aide des muons atmosphériques : Tomographic imaging of volcanoes using atmospheric muons. [Internet] [Doctoral dissertation]. Université Blaise-Pascale, Clermont-Ferrand II; 2016. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2016CLF22786.
Council of Science Editors:
Béné S. Imagerie tomograpbique d'un volcan à l'aide des muons atmosphériques : Tomographic imaging of volcanoes using atmospheric muons. [Doctoral Dissertation]. Université Blaise-Pascale, Clermont-Ferrand II; 2016. Available from: http://www.theses.fr/2016CLF22786
21.
Perrot, Yann.
Evaluation de la dose déposée par des faisceaux d'électrons en radiothérapie dans des fantômes voxelisés en utilisant la plateforme de simulation Monte Carlo GATE fondée sur GEANT4 dans un environnement de grille : Evaluation of the dose deposited by electron beams in radiotherapy in voxelized phantoms using the Monte Carlo GATE simulation platform based on GEANT4 in a grid environment.
Degree: Docteur es, Physique Corpusculaire, 2011, Université Blaise-Pascale, Clermont-Ferrand II
URL: http://www.theses.fr/2011CLF22188
► La planification de traitement en radiothérapie nécessite un calcul précis de la dose délivrée au patient. La méthode la plus fiable pour y parvenir est…
(more)
▼ La planification de traitement en radiothérapie nécessite un calcul précis de la dose délivrée au patient. La méthode la plus fiable pour y parvenir est la simulation du transport des particules par technique Monte Carlo. Cette thèse constitue la première étude concernant la validation de la plateforme de simulation Monte Carlo GATE (GEANT4 Application for Tomographic Emission), basée sur les librairies de GEANT4 (GEometry ANd Tracking), pour le calcul de la dose absorbée déposée par des faisceaux d’électrons. L’objectif de cette thèse est de montrer que GATE/GEANT4 est capable d’atteindre le niveau d’exigences requis pour le calcul de la dose absorbée lors d’une planification de traitement, dans des situations où les algorithmes analytiques, actuellement utilisés dans les services de radiothérapie, n’atteignent pas un niveau de précision satisfaisant. L’enjeu est de prouver que GATE/GEANT4 est adapté pour la planification de traitement utilisant des électrons et capable de rivaliser avec d’autres codes Monte Carlo reconnus. Cet enjeu a été démontré par la simulation avec GATE/GEANT4 de faisceaux et des sources d’électrons réalistes utilisées en radiothérapie externe ou en radiothérapie moléculaire et la production de distributions de dose absorbée en accord avec les mesures expérimentales et avec d’autres codes Monte Carlo de référence pour la physique médicale. Par ailleurs, des recommandations quant à l’utilisation des paramètres de simulation à fixer, assurant un calcul de la distribution de dose absorbée satisfaisant les spécifications en radiothérapie, sont proposées.
Radiation therapy treatment planning requires accurate determination of absorbed dose in the patient. Monte Carlo simulation is the most accurate method for solving the transport problem of particles in matter. This thesis is the first study dealing with the validation of the Monte Carlo simulation plateform GATE (GEANT4 Application for Tomographic Emission), based on GEANT4 (GEometry And Tracking) libraries, for the computation of absorbed dose deposited by electron beams. This thesis aims at demonstrating that GATE/GEANT4 calculations are able to reach treatment planning requirements in situations where analatycal algorithms are not satisfactory. The goal is to prove that GATE/GEANT4 is useful for treatment planning using electrons and competes with well validated Monte Carlo codes. This is demonstrated by the simulations with GATE/GEANT4 of realistic electron beams and electron sources used for external radiation therapy or targeted radiation therapy. The computed absorbed dose distributions are in agreement with experimental measurements and/or calculations from other Monte Carlo codes. Furthermore, guidelines are proposed to fix the physics parameters of the GATE/GEANT4 simulations in order to ensure the accuracy of absorbed dose calculations according to radiation therapy requirements.
Advisors/Committee Members: Breton, Vincent (thesis director).
Subjects/Keywords: Radiothérapie; Faisceaux d’électrons; Simulations Monte Carlo; GATE/GEANT4; Radiation therapy; Electron beams; Monte Carlo simulations; GATE/GEANT4
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Perrot, Y. (2011). Evaluation de la dose déposée par des faisceaux d'électrons en radiothérapie dans des fantômes voxelisés en utilisant la plateforme de simulation Monte Carlo GATE fondée sur GEANT4 dans un environnement de grille : Evaluation of the dose deposited by electron beams in radiotherapy in voxelized phantoms using the Monte Carlo GATE simulation platform based on GEANT4 in a grid environment. (Doctoral Dissertation). Université Blaise-Pascale, Clermont-Ferrand II. Retrieved from http://www.theses.fr/2011CLF22188
Chicago Manual of Style (16th Edition):
Perrot, Yann. “Evaluation de la dose déposée par des faisceaux d'électrons en radiothérapie dans des fantômes voxelisés en utilisant la plateforme de simulation Monte Carlo GATE fondée sur GEANT4 dans un environnement de grille : Evaluation of the dose deposited by electron beams in radiotherapy in voxelized phantoms using the Monte Carlo GATE simulation platform based on GEANT4 in a grid environment.” 2011. Doctoral Dissertation, Université Blaise-Pascale, Clermont-Ferrand II. Accessed March 04, 2021.
http://www.theses.fr/2011CLF22188.
MLA Handbook (7th Edition):
Perrot, Yann. “Evaluation de la dose déposée par des faisceaux d'électrons en radiothérapie dans des fantômes voxelisés en utilisant la plateforme de simulation Monte Carlo GATE fondée sur GEANT4 dans un environnement de grille : Evaluation of the dose deposited by electron beams in radiotherapy in voxelized phantoms using the Monte Carlo GATE simulation platform based on GEANT4 in a grid environment.” 2011. Web. 04 Mar 2021.
Vancouver:
Perrot Y. Evaluation de la dose déposée par des faisceaux d'électrons en radiothérapie dans des fantômes voxelisés en utilisant la plateforme de simulation Monte Carlo GATE fondée sur GEANT4 dans un environnement de grille : Evaluation of the dose deposited by electron beams in radiotherapy in voxelized phantoms using the Monte Carlo GATE simulation platform based on GEANT4 in a grid environment. [Internet] [Doctoral dissertation]. Université Blaise-Pascale, Clermont-Ferrand II; 2011. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2011CLF22188.
Council of Science Editors:
Perrot Y. Evaluation de la dose déposée par des faisceaux d'électrons en radiothérapie dans des fantômes voxelisés en utilisant la plateforme de simulation Monte Carlo GATE fondée sur GEANT4 dans un environnement de grille : Evaluation of the dose deposited by electron beams in radiotherapy in voxelized phantoms using the Monte Carlo GATE simulation platform based on GEANT4 in a grid environment. [Doctoral Dissertation]. Université Blaise-Pascale, Clermont-Ferrand II; 2011. Available from: http://www.theses.fr/2011CLF22188
22.
Richard, Marie-Hélène.
Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie.
Degree: Docteur es, Physique, 2012, Université Claude Bernard – Lyon I
URL: http://www.theses.fr/2012LYO10124
► L'hadronthérapie est une technique innovante de radiothérapie par ions carbone ou protons visant à améliorer les traitements actuels. La précision balistique accrue renforce la nécessité…
(more)
▼ L'hadronthérapie est une technique innovante de radiothérapie par ions carbone ou protons visant à améliorer les traitements actuels. La précision balistique accrue renforce la nécessité d'un contrôle du dépôt de dose, si possible en temps réel. Une manière de réaliser ce contrôle est de détecter avec une caméra Compton le gamma prompt émis lors des fragmentations nucléaires pendant l'irradiation du patient. Dans un premier temps, la géométrie de deux types de caméra Compton (double diffusion puis simple diffusion) a été optimisée par simulation Monte Carlo. Cette optimisation a été réalisée en étudiant la réponse des caméras à une source ponctuelle de photons avec un spectre en énergie réaliste. La réponse de la caméra optimisée à l'irradiation d'un fantôme d'eau par un faisceau d'ions carbone ou de protons a ensuite été simulée. Ces simulations ont tout d'abord été confrontées à des mesures effectuées avec un prototype de taille réduite. Ces mesures ont ensuite été utilisées pour évaluer les taux de comptage dans les détecteurs attendus en conditions cliniques. Dans la configuration actuelle de la caméra, ces taux sont élevés et les phénomènes d'empilement risquent d'être problématiques. Enfin, il est démontré que le dispositif étudié est sensible à un déplacement du pic de Bragg de plus ou moins 5 mm malgré les problèmes de coïncidences fortuites et malgré le bruit introduit par l'algorithme de reconstruction utilisé.
Ion beam therapy is an innovative radiotherapy technique using mainly carbon ion and proton irradiations. Its aim is to improve the current treatment modalities. Because of the sharpness of the dose distributions, a control of the dose if possible in real time is highly desirable. A possibility is to detect the prompt gamma rays emitted subsequently to the nuclear fragmentations occurring during the treatment of the patient. In a first time two different Compton cameras (double and single scattering) have been optimised by means of Monte Carlo simulations. The response of the camera to a photon point source with a realistic energy spectrum was studied. Then, the response of the camera to the irradiation of a water phantom by a proton beam was simulated. It was first compared with measurement performed with small-size detectors. Then, using the previous measurements, we evaluated the counting rates expected in clinical conditions. In the current set-up of the camera, these counting rates are pretty high. Pile up and random coincidences will be problematic. Finally we demonstrate that the detection system is capable to detect a longitudinal shift in the Bragg peak of +or- 5 mm, even with the current reconstruction algorithm.
Advisors/Committee Members: Ray, Cédric (thesis director), Létang, Jean-Michel (thesis director).
Subjects/Keywords: Hadronthérapie; Geant4; Monte Carlo; Gamma prompts; Ion beam therapy; Geant4; Monte Carlo; Compton camera; Prompt gamma ray; 537.535
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Richard, M. (2012). Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie. (Doctoral Dissertation). Université Claude Bernard – Lyon I. Retrieved from http://www.theses.fr/2012LYO10124
Chicago Manual of Style (16th Edition):
Richard, Marie-Hélène. “Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie.” 2012. Doctoral Dissertation, Université Claude Bernard – Lyon I. Accessed March 04, 2021.
http://www.theses.fr/2012LYO10124.
MLA Handbook (7th Edition):
Richard, Marie-Hélène. “Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie.” 2012. Web. 04 Mar 2021.
Vancouver:
Richard M. Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie. [Internet] [Doctoral dissertation]. Université Claude Bernard – Lyon I; 2012. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2012LYO10124.
Council of Science Editors:
Richard M. Design study of a Compton camera for prompts-gamma imaging during ion beam therapy : Conception d'une caméra Compton pour le contrôle en ligne en hadronthérapie. [Doctoral Dissertation]. Université Claude Bernard – Lyon I; 2012. Available from: http://www.theses.fr/2012LYO10124

Université de Bordeaux I
23.
Tran, Ngoc Hoang.
Extension et validation de l’outil Geant4 dans le cadre du projet Geant4-DNA pour la prédiction des dommages biologiques radio-induits à l’échelle cellulaire : Sur la validation des modèles paramétriques appliqués en analyse de survie et fiabilité.
Degree: Docteur es, Physique nucléaire, 2012, Université de Bordeaux I
URL: http://www.theses.fr/2012BOR14575
► L’étude des effets biologiques des radiations ionisantes à l’échelle de la cellule individuelle et en particulier sur l’ADN du noyau cellulaire reste un enjeu majeur…
(more)
▼ L’étude des effets biologiques des radiations ionisantes à l’échelle de la cellule individuelle et en particulier sur l’ADN du noyau cellulaire reste un enjeu majeur de la radiobiologie actuelle. L’objectif principal des recherches actuelles est de déterminer quels peuvent être les effets biologiques délétères des radiations ionisantes pour la santé humaine, en particulier dans le domaine des faibles doses de radiation. Afin d’étudier précisément la réponse des cellules aux radiations ionisantes, de nombreuses études expérimentales des effets des radiations ionisantes sur les cellules, tissus et organismes biologiques aux basses énergies ont accumulées de grandes quantités de données de qualité sur la réponse de cellules aux radiations. Il existe également de nombreux modèles semi-empiriques de survie cellulaire qui incorporent des paramètres biologiques et physiques. En parallèle, des stochastiques basées sur la technique « Monte Carlo » pour modéliser les processus élémentaires en physique, chimie et biologie sont en cours de développement. L’outil
Geant4 développé dès 1993 (CERN et KEK) en utilisant des techniques informatiques de dernière génération (C++) permet à l’utilisateur de construire une simulation complète grâce à de nombreuses fonctionnalités : formes géométriques, matériaux, particules élémentaires, processus physiques électromagnétiques et hadroniques, visualisation, analyse de données, interactivité et extensibilité… Cependant,
Geant4 présente un certain nombre de limitations pour la simulation des effets biologiques des radiations ionisants à l’échelle subcellulaire : les modèles standard ne prennent pas compte le technique « pas-à-pas », les modèles physique sont limités à basse énergie, il n’a pas des descriptions des cibles moléculaires et
Geant4 n’est pas capable de simuler les étapes physico-chimique et chimique nécessaire pour déterminer l’oxydation des bases et les éventuelles cassures d’ADN.Dans ce contexte, le projet
Geant4-DNA propose d’étendre
Geant4 afin de modéliser les interactions des radiations ionisantes à l’échelle de la cellule biologique et la molécule d’ADN et aux basses énergies. Au cours du travail de thèse, j’ai tout d’abord validé les modèles physiques en comparant les résultats de simulation à une grande collection de données expérimentales disponibles dans la littérature. L’accord entre les valeurs de sections efficaces totales et différentielles et les mesures expérimentales a été quantifié à l’aide du test statistique Kolmogorov-Smirnov. J’ai par la suite amélioré les classes des processus de diffusion élastique des électrons et travailler sur les calculs théoriques du modèle de diffusion élastique des protons et des alphas dans l’eau liquide auparavant inexistant dans
Geant4-DNA. J’ai effectué une combinaison des processus multi-échelles des modèles de
Geant4-DNA (à l’échelle microscopique) avec les modèles électromagnétiques disponibles dans l’outil
Geant4 (les processus d’interaction des photons et autres modèles de
Geant4). A la fin de mon travail, j’ai participé à…
Advisors/Committee Members: Incerti, Sébastien (thesis director), Champion, Christophe (thesis director).
Subjects/Keywords: Geant4-DNA; Monte Carlo; Simulation; Modalisation; Physiques médical; Dommages biologiques; Geant4-DNA; Monte Carlo; Simulation; Modeling; Medical physics; Biological damages
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tran, N. H. (2012). Extension et validation de l’outil Geant4 dans le cadre du projet Geant4-DNA pour la prédiction des dommages biologiques radio-induits à l’échelle cellulaire : Sur la validation des modèles paramétriques appliqués en analyse de survie et fiabilité. (Doctoral Dissertation). Université de Bordeaux I. Retrieved from http://www.theses.fr/2012BOR14575
Chicago Manual of Style (16th Edition):
Tran, Ngoc Hoang. “Extension et validation de l’outil Geant4 dans le cadre du projet Geant4-DNA pour la prédiction des dommages biologiques radio-induits à l’échelle cellulaire : Sur la validation des modèles paramétriques appliqués en analyse de survie et fiabilité.” 2012. Doctoral Dissertation, Université de Bordeaux I. Accessed March 04, 2021.
http://www.theses.fr/2012BOR14575.
MLA Handbook (7th Edition):
Tran, Ngoc Hoang. “Extension et validation de l’outil Geant4 dans le cadre du projet Geant4-DNA pour la prédiction des dommages biologiques radio-induits à l’échelle cellulaire : Sur la validation des modèles paramétriques appliqués en analyse de survie et fiabilité.” 2012. Web. 04 Mar 2021.
Vancouver:
Tran NH. Extension et validation de l’outil Geant4 dans le cadre du projet Geant4-DNA pour la prédiction des dommages biologiques radio-induits à l’échelle cellulaire : Sur la validation des modèles paramétriques appliqués en analyse de survie et fiabilité. [Internet] [Doctoral dissertation]. Université de Bordeaux I; 2012. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2012BOR14575.
Council of Science Editors:
Tran NH. Extension et validation de l’outil Geant4 dans le cadre du projet Geant4-DNA pour la prédiction des dommages biologiques radio-induits à l’échelle cellulaire : Sur la validation des modèles paramétriques appliqués en analyse de survie et fiabilité. [Doctoral Dissertation]. Université de Bordeaux I; 2012. Available from: http://www.theses.fr/2012BOR14575
24.
Perier, Aurélien.
Modes d’exposition au xénon-133 dans un bâtiment réacteur : Exposure mode study to xenon-133 in a reactor building.
Degree: Docteur es, Constituants élémentaires et physique théorique, 2014, Nantes, Ecole des Mines
URL: http://www.theses.fr/2014EMNA0184
► Le travail décrit dans cette thèse porte sur l’évaluation du mode d’exposition externe et interne au xénon-133. Ce radionucléide est un des principaux produits de…
(more)
▼ Le travail décrit dans cette thèse porte sur l’évaluation du mode d’exposition externe et interne au xénon-133. Ce radionucléide est un des principaux produits de fission du combustible des réacteurs nucléaires. En cas de défaut de gaine combustible, le xénon-133 peut potentiellement exposer le personnel lors de ses interventions dans le bâtiment réacteur. En dosimétrie, les simulations Monte-Carlo sont des outils adaptés pour simuler le transport des rayonnements ionisants dans la matière. A partir des critères de radioprotection actuels, nous avons développé de nouvelles méthodes afin d’améliorer notre compréhension de l’exposition externe et interne auxénon-133 à l’intérieur d’un bâtiment réacteur. Ces nouvelles approches sont basées sur l’utilisation d’un fantôme anthropomorphe, d’une géométrie réaliste de bâtiment réacteur, de simulations Monte-Carlo GEANT4 et de modèles en compartiments. L’exposition externe dans un bâtiment réacteur a été menée en retenant un scénario d’exposition réaliste et conservatif. Nous avons quantifié le débit de dose efficace et le débit de dose équivalente au cristallin. L’exposition interne se produit lorsque le xénon-133 est inhalé. Les poumons sont les premiers organes exposés par l’inhalation du xénon-133, leur débit de dose équivalente a été quantifié. Un modèle biocinétique a été utilisé pour évaluer l’exposition interne au xénon-133. Cette thèse a permis de quantifier les grandeurs dosimétriques liées aux modes d’exposition externe et interne au xénon-133, d’étudier l’impact des changements de limites dosimétriques introduits par la Commission Internationale de Radioprotection prochainement retranscrits dans la réglementation française, et de comprendre la cinétique du xénon-133 dans le corps humain. Nous avons montré que les grandeurs dosimétriques sont nettement inférieures aux limites dosimétriques de la réglementation actuelle et future.
The work described in this thesis focuses on the external and internal dose assessment to xenon-133. During the nuclear reactor operation, fission products and radioactive inert gases, as ¹³³Xe, are generated and might be responsible for the exposure of workers incase of clad defect.Particle Monte Carlo transport code is adapted inradioprotection to quantify dosimetric quantities.The study of exposure to xenon-133 is conducted byusing Monte-Carlo simulations based on GEANT4, ananthropomorphic phantom, a realistic geometry of thereactor building, and compartmental models.The external exposure inside a reactor building isconducted with a realistic and conservative exposurescenario. The effective dose rate and the eye lensequivalent dose rate are determined by Monte-Carlosimulations. Due to the particular emission spectrum ofxenon-133, the equivalent dose rate to the lens of eyesis discussed in the light of expected new eye doselimits.The internal exposure occurs while xenon-133 isinhaled. The lungs are firstly exposed by inhalation, andtheir equivalent dose rate is obtained by Monte-Carlosimulations. A biokinetic model is used to evaluate…
Advisors/Committee Members: Grambow, Bernd (thesis director).
Subjects/Keywords: Xénon-133; Fantôme anthropomorphe; Calcul Monte-Carlo; GEANT4; Radioprotection; Xenon-133; Anthropomorphic phantom; Monte-Carlo code; GEANT4; Radioprotection
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Perier, A. (2014). Modes d’exposition au xénon-133 dans un bâtiment réacteur : Exposure mode study to xenon-133 in a reactor building. (Doctoral Dissertation). Nantes, Ecole des Mines. Retrieved from http://www.theses.fr/2014EMNA0184
Chicago Manual of Style (16th Edition):
Perier, Aurélien. “Modes d’exposition au xénon-133 dans un bâtiment réacteur : Exposure mode study to xenon-133 in a reactor building.” 2014. Doctoral Dissertation, Nantes, Ecole des Mines. Accessed March 04, 2021.
http://www.theses.fr/2014EMNA0184.
MLA Handbook (7th Edition):
Perier, Aurélien. “Modes d’exposition au xénon-133 dans un bâtiment réacteur : Exposure mode study to xenon-133 in a reactor building.” 2014. Web. 04 Mar 2021.
Vancouver:
Perier A. Modes d’exposition au xénon-133 dans un bâtiment réacteur : Exposure mode study to xenon-133 in a reactor building. [Internet] [Doctoral dissertation]. Nantes, Ecole des Mines; 2014. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2014EMNA0184.
Council of Science Editors:
Perier A. Modes d’exposition au xénon-133 dans un bâtiment réacteur : Exposure mode study to xenon-133 in a reactor building. [Doctoral Dissertation]. Nantes, Ecole des Mines; 2014. Available from: http://www.theses.fr/2014EMNA0184
25.
Pepitone, Kévin.
Etude de la production, de la propagation et de la focalisation d'un faisceau d'électrons impulsionnel intense : Study of the production, the propagation and the focusing of an electron beam.
Degree: Docteur es, Astrophysique, plasmas, nucléaire, 2014, Bordeaux
URL: http://www.theses.fr/2014BORD0158
► Le faisceau d’électrons (500 keV, 30 kA, 100 ns) produit par le générateur RKA (Relativistic Klystron Amplifier) est utilisé pour étudier des matériaux soumis à…
(more)
▼ Le faisceau d’électrons (500 keV, 30 kA, 100 ns) produit par le générateur RKA (Relativistic Klystron Amplifier) est utilisé pour étudier des matériaux soumis à des chocs de basse fluence (< 10 cal/cm²). Leur réponse dépend des caractéristiques du faisceau, principalement en termes d’homogénéité spatiale lors de l’impact. Dans ce but, nous avons utilisé des diagnostics électriques et un diagnostic optique basé sur l’émission Cerenkov. Les photons visibles produits sont détectables par des caméras rapides. Nous avons ainsi pu étudier l’homogénéité du faisceau émis dans la diode sous vide en fonction des matériaux utilisés pour la cathode et pour l’anode, mais aussi pu suivre sa propagation dans une enceinte contenant un gaz à basse pression.Chaque partie de l’installation a été optimisée lors de cette thèse. Nous avons constaté qu’une cathode en velours avec des fibres bien ordonnées était le meilleur émetteur. Une anode d’une dizaine de micromètres d’épaisseur permet de diffuser le faisceau avant qu’il n’impacte la cible, améliorant encore son homogénéité. Ces travaux sur la diode ont été complétés par une étude de la propagation du faisceau dans une enceinte remplie d’air ou d’argon à différentes pressions, avec ou sans focalisation produite par un champ magnétique externe. D’après les résultats expérimentaux, un faisceau d’électrons de 400 keV, 4,2 kA peut être propagé, avec un rayon constant, dans 0,7 mbar d’argon. Enfin, pour interpréter les expériences, des simulations ont été réalisées à l’aide du code Monte Carlo Geant4 pour calculer l’interaction du faisceau avec la cible Cerenkov et l’anode. Au niveau de l’émission et du transport du faisceau, le bon accord obtenu avec les prédictions du code PIC Magic permet d’estimer les distributions des électrons par la simulation et d’initialiser correctement les calculs de réponse des matériaux.
The electron beam (500 keV, 30 kA, 100 ns) of the RKA (Relativistic Klystron Amplifier) generator is used to study materials under shocks at low fluences (< 10 cal/cm²). Their response depends on the beam characteristics at the impact location, mainly in terms of spatial homogeneity. We have used electrical diagnostics as well as an optical diagnostics where the visible photons produced by Cerenkov emission in a silica target are collected by fast cameras. Beam homogeneity has been studied in the vacuum diode as a function of the materials used for the cathode and the anode. Beam propagation and focusing in a chamber filled with a low-pressure gas has also been investigated.Each part of the installation has been optimized during this work. We found that, among the tested materials, a velvet cathode with well-aligned fibers is the best emitter. An anode of thickness about ten micrometers improves the beam homogeneity by scattering of electrons. Next, we focused on beam propagation and focusing in the chamber. For example, a 400 keV, 4.2 kA electron beam can be propagated at constant radius in argon at 0.7 mbar. We performed simulations with the Monte Carlo code Geant4 in…
Advisors/Committee Members: Tikhonchuk, Vladimir (thesis director), Gardelle, Jacques (thesis director).
Subjects/Keywords: Faisceau d’électrons; Propagation; Focalisation; Production; Effet Cerenkov; Geant4; Durcissement; Electron beam; Propagation; Focusing; Production; Cerenkov emission; Geant4; Homogeneity
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APA ·
Chicago ·
MLA ·
Vancouver ·
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Export
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APA (6th Edition):
Pepitone, K. (2014). Etude de la production, de la propagation et de la focalisation d'un faisceau d'électrons impulsionnel intense : Study of the production, the propagation and the focusing of an electron beam. (Doctoral Dissertation). Bordeaux. Retrieved from http://www.theses.fr/2014BORD0158
Chicago Manual of Style (16th Edition):
Pepitone, Kévin. “Etude de la production, de la propagation et de la focalisation d'un faisceau d'électrons impulsionnel intense : Study of the production, the propagation and the focusing of an electron beam.” 2014. Doctoral Dissertation, Bordeaux. Accessed March 04, 2021.
http://www.theses.fr/2014BORD0158.
MLA Handbook (7th Edition):
Pepitone, Kévin. “Etude de la production, de la propagation et de la focalisation d'un faisceau d'électrons impulsionnel intense : Study of the production, the propagation and the focusing of an electron beam.” 2014. Web. 04 Mar 2021.
Vancouver:
Pepitone K. Etude de la production, de la propagation et de la focalisation d'un faisceau d'électrons impulsionnel intense : Study of the production, the propagation and the focusing of an electron beam. [Internet] [Doctoral dissertation]. Bordeaux; 2014. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2014BORD0158.
Council of Science Editors:
Pepitone K. Etude de la production, de la propagation et de la focalisation d'un faisceau d'électrons impulsionnel intense : Study of the production, the propagation and the focusing of an electron beam. [Doctoral Dissertation]. Bordeaux; 2014. Available from: http://www.theses.fr/2014BORD0158

Université Paris-Sud – Paris XI
26.
Ogheard, Florestan.
Développement d’un système de mesure directe du débit d’émission de sources neutroniques : Development of a direct measurement system for the standardization of neutron emission rates.
Degree: Docteur es, Physique nucléaire, 2012, Université Paris-Sud – Paris XI
URL: http://www.theses.fr/2012PA112176
► La méthode de mesure de référence du débit d’émission de sources neutroniques se fonde sur la technique du bain de manganèse. Elle est destinée à…
(more)
▼ La méthode de mesure de référence du débit d’émission de sources neutroniques se fonde sur la technique du bain de manganèse. Elle est destinée à étalonner des sources de neutrons utilisant des radionucléides (241AmBe, 239PuBe, 252Cf,…) en termes de débit d’émission neutronique sous 4π sr. Ce dispositif est complété par un banc de mesure de l’anisotropie d’émission utilisant un support rotatif et un compteur long de type BF3. La source à mesurer est immergée dans une solution de sulfate de manganèse et les neutrons émis sont capturés par les constituants du bain. Dans une configuration classique (sphère de bain de manganèse de 1 m de diamètre et solution concentrée), environ la moitié de ces neutrons conduisent à la création de 56Mn par réaction (n, γ) sur 55Mn. Le radionucléide 56Mn a une période radioactive d’environ 2,6 heures et le bain de manganèse atteint son activité de saturation en 56Mn quand le nombre d’atomes radioactifs créés par unité de temps devient égal au nombre d’atomes se désintégrant pendant ce même temps. Le débit d’émission de la source peut alors être déduit de l’activité en 56Mn de la solution à saturation, via une modélisation ad hoc des réactions nucléaires se produisant dans le bain. Cette installation a été récemment rénovée au LNE-LNHB afin de respecter les règles de sécurité et de radioprotection en vigueur. Cette rénovation a été l’occasion de moderniser et de remettre à niveau les méthodes de mesure et de modélisation du bain et d’entreprendre une étude sur le développement d’un détecteur original pour la mesure directe en ligne de l’activité du manganèse. Ce détecteur est fondé sur la méthode de mesure par coïncidences β-γ. La voie bêta est constituée de deux photomultiplicateurs permettant de détecter l’émission de lumière due à l’effet Cerenkov et la voie gamma utilise un détecteur à scintillateur solide. L’intérêt de cette méthode de mesure est qu’elle permet d’avoir accès à l’activité du bain sans nécessiter d’étalonnage préalable, contrairement à la méthode classique qui utilise un compteur gamma et nécessite la fabrication d’une source de haute activité. Le principe de mesure a été validé à l'aide d'un prototype de détecteur et d'une modélisation effectuée à l'aide du code de calcul stochastique
GEANT4. Le détecteur définitif a été réalisé et les mesures obtenues ont été comparées à celles données par une méthode primaire présente au laboratoire. Par ailleurs, des modélisations du bain de manganèse effectuées sous
GEANT4, MCNPX et FLUKA, ont été comparées afin de choisir le code le plus fiable. Cette comparaison a permis d'identifier des lacunes notamment dans le code
GEANT4 ainsi que des facteurs d'incertitude nécessitant une attention particulière, tels que la modélisation de l'émission neutronique et le choix des sections efficaces. Enfin, un étalonnage de source neutronique a été réalisé grâce à la méthode Cerenkov-gamma et aux facteurs correctifs donnés par la nouvelle modélisation du bain sous MCNPX. Ces mesures ont été complétées dans le cadre d'une comparaison comprenant…
Advisors/Committee Members: Cassette, Philippe (thesis director).
Subjects/Keywords: Source neutronique; Bain de manganèse; Étalonnage; Métrologie; GEANT4; MCNPX; Neutron source; Manganese bath; Calibration; Metrology; GEANT4; MCNPX
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ogheard, F. (2012). Développement d’un système de mesure directe du débit d’émission de sources neutroniques : Development of a direct measurement system for the standardization of neutron emission rates. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2012PA112176
Chicago Manual of Style (16th Edition):
Ogheard, Florestan. “Développement d’un système de mesure directe du débit d’émission de sources neutroniques : Development of a direct measurement system for the standardization of neutron emission rates.” 2012. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed March 04, 2021.
http://www.theses.fr/2012PA112176.
MLA Handbook (7th Edition):
Ogheard, Florestan. “Développement d’un système de mesure directe du débit d’émission de sources neutroniques : Development of a direct measurement system for the standardization of neutron emission rates.” 2012. Web. 04 Mar 2021.
Vancouver:
Ogheard F. Développement d’un système de mesure directe du débit d’émission de sources neutroniques : Development of a direct measurement system for the standardization of neutron emission rates. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2012. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2012PA112176.
Council of Science Editors:
Ogheard F. Développement d’un système de mesure directe du débit d’émission de sources neutroniques : Development of a direct measurement system for the standardization of neutron emission rates. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2012. Available from: http://www.theses.fr/2012PA112176
27.
Paschalis, Pavlos.
Έλεγχος ποιότητας δεδομένων υψηλής ανάλυσης των μετρητών νετρονίων και ανάπτυξη τεχνικών προσομοίωσης.
Degree: 2014, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)
URL: http://hdl.handle.net/10442/hedi/35224
► It is well known that the neutron monitors are still the most reliable detectors for the measurements of the cosmic ray intensity. The foundation of…
(more)
▼ It is well known that the neutron monitors are still the most reliable detectors for the measurements of the cosmic ray intensity. The foundation of the High resolution Neutron Monitor Database in real time (NMDB), has created the need of high quality data provided from each one of the cosmic ray stations including the one of the University of Athens, where this thesis was completed. For this purpose, a series of data correction algorithms have been created, the ANN and ANN Plus based on artificial neural networks, the Edge Editor based on statistical criteria and an optimized version of the established Median Editor. The excellence of the Edge Editor has been proven and evaluated by the scientific community. For the pressure corrected data, a method for the calculation of the barometric coefficient by using a reference station has been developed. For the management of the measurements, a number of applications have been developed which are currently in use at the Athens' station with reliable results. Finally, simulations with Geant4 have been developed, for the study of the Neutron Monitors and of the particle cascades in the Earth's atmosphere with very impressive results, which allow future applications in Space weather.
Είναι γνωστό ότι οι μετρητές νετρονίων παραμένουν οι πιο αξιόπιστοι και μακρόχρονοι ανιχνευτές της έντασης της κοσμικής ακτινοβολίας. Η δημιουργία της διεθνούς βάσης NMDB, όπου συλλέγονται τα υψηλής ανάλυσης δεδομένα των Μετρητών Νετρονίων σε πραγματικό χρόνο, δημιούργησε την ανάγκη ελέγχου της ποιότητος των δεδομένων που παρέχονται από όλους τους σταθμούς κοσμικής ακτινοβολίας, μεταξύ των οποίων και του Πανεπιστημίου Αθηνών στον οποίο διεξήχθη η παρούσα διατριβή. Για τον σκοπό αυτό αναπτύχτηκε μια σειρά από νέους αλγορίθμους διόρθωσης των δεδομένων, οι ANN και ANN Plus βασισμένοι σε τεχνητά νευρωνικά δίκτυα, ο Edge Editor βασισμένος σε στατιστικά κριτήρια, καθώς και μία βελτιστοποιημένη έκδοση του καθιερωμένου Median Editor. Η υπεροχή του Edge Editor απεδείχθη και αξιολογήθηκε από την επιστημονική κοινότητα. Για τη διόρθωση των μετρήσεων ως προς την πίεση αναπτύχτηκε μέθοδος προσδιορισμού του βαρομετρικού συντελεστή με χρήση σταθμού αναφοράς. Για τη διαχείριση των μετρήσεων υλοποιήθηκε μια σειρά εφαρμογών, οι οποίες λειτουργούν αξιόπιστα στο σταθμό της Αθήνας. Τέλος, πραγματοποιήθηκαν προσομοιώσεις με χρήση του πακέτου Geant4, τόσο για τη μελέτη του Μετρητή Νετρονίων όσο και των καταιονισμών σωματιδίων εντός της γήινης ατμόσφαιρας με πολύ εντυπωσιακά αποτελέσματα, τα οποία ανοίγουν το δρόμο για μελλοντικές εφαρμογές στο Διαστημικό καιρό.
Subjects/Keywords: Κοσμική ακτινοβολία; Μετρητής νετρονίων; Προσομοιώσεις GEANT4; Αλγόριθμοι διόρθωσης δεδομένων; Cosmic rays; Neutron monitor; Simulations GEANT4; Algorithms data correction
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Paschalis, P. (2014). Έλεγχος ποιότητας δεδομένων υψηλής ανάλυσης των μετρητών νετρονίων και ανάπτυξη τεχνικών προσομοίωσης. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/35224
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Paschalis, Pavlos. “Έλεγχος ποιότητας δεδομένων υψηλής ανάλυσης των μετρητών νετρονίων και ανάπτυξη τεχνικών προσομοίωσης.” 2014. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed March 04, 2021.
http://hdl.handle.net/10442/hedi/35224.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Paschalis, Pavlos. “Έλεγχος ποιότητας δεδομένων υψηλής ανάλυσης των μετρητών νετρονίων και ανάπτυξη τεχνικών προσομοίωσης.” 2014. Web. 04 Mar 2021.
Vancouver:
Paschalis P. Έλεγχος ποιότητας δεδομένων υψηλής ανάλυσης των μετρητών νετρονίων και ανάπτυξη τεχνικών προσομοίωσης. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2014. [cited 2021 Mar 04].
Available from: http://hdl.handle.net/10442/hedi/35224.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Paschalis P. Έλεγχος ποιότητας δεδομένων υψηλής ανάλυσης των μετρητών νετρονίων και ανάπτυξη τεχνικών προσομοίωσης. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 2014. Available from: http://hdl.handle.net/10442/hedi/35224
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
28.
Lampe, Nathanael.
De l’impact à long terme des radiations ionisantes sur les systèmes vivants : The long term impact of ionising radiation on living systems.
Degree: Docteur es, Physique, 2017, Université Clermont Auvergne (2017-2020)
URL: http://www.theses.fr/2017CLFAC011
► La vie sur Terre s’est adaptée à un environnement où il y a un faible et persistent bruit de fond radiatif qui interagit avec les…
(more)
▼ La vie sur Terre s’est adaptée à un environnement où il y a un faible et persistent bruit de fond radiatif qui interagit avec les cellules. Loin des effets clairement nocifs des radiations à haute dose, il est difficile d’évaluer et de comprendre les impacts des faibles doses de la radioactivité naturelle sur les systèmes vivants. Nous avons tenté d’étudier si le bruit de fond radiatif est un facteur important dans l’évolution, en menant des expériences évolutives identiques avec Escherichia coli au Laboratoire de Physique Corpusculaire de Clermont-Ferrand, et au Laboratoire Souterrain de Modane. Malgré une différence d’un facteur 7,3 entre les taux d’interaction des rayonnements ionisants avec les cellules dans les deux laboratoires, aucune différence significative n’a pu être trouvée dans le fitness compétitif des populations cellulaires évoluées dans chaque laboratoire. Par simulation, nous avons montré que le taux d’interaction entre le bruit de fond radiatif et E. coli est cent fois plus faible que le taux de mutations d’origine endémique, ce qui renforce l’hypothèse que les radiations naturelles ont peu d’effet sur l’évolution. Dans le cadre du projet Geant4-DNA, nous avons développé une application complète de simulation mécanistique des dommages radio-induits à l’ADN, afin d’explorer davantage cette hypothèse. Avec cette application, on a irradié un modèle du génome d’E. coli, montrant que pour l’irradiation par des électrons d’énergies > 10 keV, le rendement des cassures double brin est de 0,006 – 0,010 CDB Gy-1 Mbp-1, selon le modèle de piégeage des radicaux chimiques. Ce résultat est en accord avec des données expérimentales, et souligne plus encore que les radiations ionisantes d’origine naturelle n’ont qu’une contribution mineure aux mutations responsables de l’évolution.
All life on earth has adapted to an environment where there is a small, persistent, radiation background interacting with cells. Unlike evaluating the clearly harmful effects of high radiation doses, understanding the effects of this low persistent radiation dose on living systems is incredibly difficult. We have attempted to study whether background radiation is an important factor in evolution by conducting identical evolution experiments with Escherichia coli in the Clermont-Ferrand Particle Physics Laboratory and the Modane Underground Laboratory. Despite a 7.3 fold difference in the rate of interactions between the radiation background and cells between the two environments, no significant difference was found in the competitive fitness of the cell populations grown at each location. Using simulations, we showed that the rate at which ionising radiation interacts with cells is one hundred times less frequent than E. coli’s mutation rate in our experimental conditions, supporting the contention that natural radiation has no strong evolutionary effect. To further support this conclusion, we developed a mechanistic simulation for DNA damage as part of the Geant4-DNA project. Using this application, we irradiated a model of an E.…
Advisors/Committee Members: Breton, Vincent (thesis director), Sarramia, David (thesis director), Incerti, Sébastien (thesis director).
Subjects/Keywords: Faibles doses de radiations; Radiation naturelle; Évolvabilité; Dommage ADN; Simulation; Geant4; Low dose radiation; Natural radiation; Evolvability; DNA damage; Simulation; Geant4
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Lampe, N. (2017). De l’impact à long terme des radiations ionisantes sur les systèmes vivants : The long term impact of ionising radiation on living systems. (Doctoral Dissertation). Université Clermont Auvergne (2017-2020). Retrieved from http://www.theses.fr/2017CLFAC011
Chicago Manual of Style (16th Edition):
Lampe, Nathanael. “De l’impact à long terme des radiations ionisantes sur les systèmes vivants : The long term impact of ionising radiation on living systems.” 2017. Doctoral Dissertation, Université Clermont Auvergne (2017-2020). Accessed March 04, 2021.
http://www.theses.fr/2017CLFAC011.
MLA Handbook (7th Edition):
Lampe, Nathanael. “De l’impact à long terme des radiations ionisantes sur les systèmes vivants : The long term impact of ionising radiation on living systems.” 2017. Web. 04 Mar 2021.
Vancouver:
Lampe N. De l’impact à long terme des radiations ionisantes sur les systèmes vivants : The long term impact of ionising radiation on living systems. [Internet] [Doctoral dissertation]. Université Clermont Auvergne (2017-2020); 2017. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2017CLFAC011.
Council of Science Editors:
Lampe N. De l’impact à long terme des radiations ionisantes sur les systèmes vivants : The long term impact of ionising radiation on living systems. [Doctoral Dissertation]. Université Clermont Auvergne (2017-2020); 2017. Available from: http://www.theses.fr/2017CLFAC011
29.
Zahradnik, Izabella Anna.
Diamond-Based Microdosimetry for Hadron Therapy : Microdosimètre en diamant pour la hadronthérapie.
Degree: Docteur es, Imagerie médicale et radioactivité, 2020, université Paris-Saclay
URL: http://www.theses.fr/2020UPASP057
► La hadronthérapie est un traitement innovant du cancer qui permet de détruire les cellules tumorales plus efficacement que par la radiothérapie conventionnelle utilisant des photons.…
(more)
▼ La hadronthérapie est un traitement innovant du cancer qui permet de détruire les cellules tumorales plus efficacement que par la radiothérapie conventionnelle utilisant des photons. Actuellement, le transfert d'énergie linéique (TEL) des particules est utilisé comme paramètre pour prédire l'efficacité biologique relative (EBR) des faisceaux de particules. Cependant les limitations de l’utilisation de ce paramètre ont conduit à l'introduction d'une quantité stochastique mesurable appelée énergie linéale des particules, qui constitue la base de la microdosimétrie. La valeur mesurée expérimentalement de l’énergie linéale est essentielle pour valider les simulations et les modèles dans l’objectif d’améliorer en conséquence l'efficacité du traitement. Actuellement, aucun détecteur microdosimétrique permettant la mesure de l'énergie linéale n'est disponible pour un usage en routine clinique. L'objectif de ce projet de doctorat est de développer un nouveau type de microdosimètre à l’état solide, équivalent au tissu, à base de diamant. Ce détecteur à haute résolution spatiale doit permettre de réaliser des mesures d'énergie linéale dans des conditions cliniques pendant un traitement de hadronthérapie. Diverses techniques de microfabrication, telles que la gravure par CVD, le dépôt de couches minces et la photolithographie, ont été utilisées pour créer des prototypes de microdosimètres en diamant au CEA, en France. Plusieurs générations de microdosimètres ont été fabriquées et caractérisées par un processus itératif afin d’aboutir à une version de dosimètre la plus optimisée possible. Les caractérisations, sous microfaisceaux de particules ont été réalisées par IBIC (Ion Beam Induce Charge) sur la plateforme AIFIRA au CENBG en France et à l’ANSTO en Australie. Les prototypes finaux ont été intégrés à une électronique multicanal appropriée et leurs performances ont été testées dans des centres médicaux de proton et d'ions lourds à l'IC-CPO en France, ainsi qu'au HIMAC au Japon. Les mesures obtenues ont été comparées à celles d'autres dispositifs développés dans ce domaine ainsi qu’aux simulations obtenues avec le codes de transport de particules Monte Carlo, Geant4.
Hadron therapy is an innovative type of radiotherapy for cancer treatment which enables tumor cells to be more effectively destroyed than by conventional radiotherapy using photons. At present, the linear energy transfer (LET) of particles is used as a fundamental parameter in predicting the relative biological effectiveness (RBE) of particle beams. However, serious limitations of the LET concept with respect to the RBE and the difference between different types of radiation have been discussed. These limitations led to the introduction of a measurable stochastic quantity called lineal energy of particles, which provides a fundamental basis for microdosimetry. Having access to such experimentally measured quantities is essential for validating simulations and models, which in turn improve the treatment efficiency. Currently, no microdosimetric detectors using…
Advisors/Committee Members: Tromson, Dominique (thesis director).
Subjects/Keywords: Hadronthérapie; Microdosimètre; Energie linéale; Diamant monocristallins CVD; IBIC; MC GEANT4; Hadron therapy; Microdosimetry; Lineal energy; ScCVD diamond; IBIC; MC GEANT4
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Zahradnik, I. A. (2020). Diamond-Based Microdosimetry for Hadron Therapy : Microdosimètre en diamant pour la hadronthérapie. (Doctoral Dissertation). université Paris-Saclay. Retrieved from http://www.theses.fr/2020UPASP057
Chicago Manual of Style (16th Edition):
Zahradnik, Izabella Anna. “Diamond-Based Microdosimetry for Hadron Therapy : Microdosimètre en diamant pour la hadronthérapie.” 2020. Doctoral Dissertation, université Paris-Saclay. Accessed March 04, 2021.
http://www.theses.fr/2020UPASP057.
MLA Handbook (7th Edition):
Zahradnik, Izabella Anna. “Diamond-Based Microdosimetry for Hadron Therapy : Microdosimètre en diamant pour la hadronthérapie.” 2020. Web. 04 Mar 2021.
Vancouver:
Zahradnik IA. Diamond-Based Microdosimetry for Hadron Therapy : Microdosimètre en diamant pour la hadronthérapie. [Internet] [Doctoral dissertation]. université Paris-Saclay; 2020. [cited 2021 Mar 04].
Available from: http://www.theses.fr/2020UPASP057.
Council of Science Editors:
Zahradnik IA. Diamond-Based Microdosimetry for Hadron Therapy : Microdosimètre en diamant pour la hadronthérapie. [Doctoral Dissertation]. université Paris-Saclay; 2020. Available from: http://www.theses.fr/2020UPASP057

RMIT University
30.
Turnbull, S.
Muon interaction with lead shielding producing activation: implications for gamma-ray spectrometry.
Degree: 2011, RMIT University
URL: http://researchbank.rmit.edu.au/view/rmit:161164
► This work investigates the generation of neutron flux inside lead shielding due to cosmic rays as a function of shielding thickness by use of the…
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▼ This work investigates the generation of neutron flux inside lead shielding due to cosmic rays as a function of shielding thickness by use of the GEANT Monte-Carlo modelling code. GEANT allows for the Monte-Carlo modelling of the transport of particles in matter. This includes muons, the particles of interest here, which originate from cosmic ray showers As part of this project an estimate of the gold activation rate, the number of 198Au isotopes produced during irradiation from neutrons produced from muon interaction with Pb in the shielding of a Gamma Ray Spectroscopy (GRS) detector, was determined. The source of the muons was cosmic rays which interacted with particles in the atmosphere. The main results of this project can be summarised as follows: 1. The creation of neutrons from muons interacting with lead shielding is a significant effect which must be taken into account in accurate GRS experiments. 2. The production of neutrons is relatively constant in the muon energy range of 200-800 MeV 3. The neutron energy spectrum is effectively the same over the muon energy range 200-800 MeV. 4. From the point of view of neutron activation of gold, the activation rate of gold atoms is maximised at muon energy of 600 MeV. Data obtained from these simulations is of general importance for the optimisation of materials used in shielding for gamma-ray spectrometry.
Subjects/Keywords: Fields of Research; Monte-Carlo modelling; GEANT4; Gamma Ray Spectroscopy
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APA (6th Edition):
Turnbull, S. (2011). Muon interaction with lead shielding producing activation: implications for gamma-ray spectrometry. (Thesis). RMIT University. Retrieved from http://researchbank.rmit.edu.au/view/rmit:161164
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Turnbull, S. “Muon interaction with lead shielding producing activation: implications for gamma-ray spectrometry.” 2011. Thesis, RMIT University. Accessed March 04, 2021.
http://researchbank.rmit.edu.au/view/rmit:161164.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Turnbull, S. “Muon interaction with lead shielding producing activation: implications for gamma-ray spectrometry.” 2011. Web. 04 Mar 2021.
Vancouver:
Turnbull S. Muon interaction with lead shielding producing activation: implications for gamma-ray spectrometry. [Internet] [Thesis]. RMIT University; 2011. [cited 2021 Mar 04].
Available from: http://researchbank.rmit.edu.au/view/rmit:161164.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Turnbull S. Muon interaction with lead shielding producing activation: implications for gamma-ray spectrometry. [Thesis]. RMIT University; 2011. Available from: http://researchbank.rmit.edu.au/view/rmit:161164
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
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