A Priori Deterministic Computational-Cost Optimization of Weight-Dependent Variance-Reduction Parameters for Monte Carlo Neutral-Particle Transport

Solomon, Clell J.; Sood, Avneet; Booth, Thomas E.; Shultis, J. Kenneth

doi:10.13182/nse12-81

Cited by 4 publications

(24 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…TPS dosimetry calculations are based on pre-calculated MC dosimetry data acquired with the 192 Ir source centred in specific phantom geometries. TPS cannot account any changes in scatter conditions imposed by phantom geometry condition and source dwell positions at different distances in phantom boundary while that is possible in the MC simulation [20][21][22][23]. Currently utilized commercial TPS ignores not only the effect of tissue heterogeneity within the patient, but also it denies the effect of the finite patient volume.…”

Section: Results Phantom Validationmentioning

confidence: 99%

“…We employed the MCNP 4C version, which was released in 1999 and has a prominent capability of geometric modeling and calculating dose distribution within the human body. This code uses a three-dimensional (3D) geometry and transports neutron, photon, and electrons in the energy range from 1 keV to 1 GeV for simulation [20][21][22][23]. Low energy phenomena, such as characteristic X-ray and Auger electrons, are accurately modeled.…”

Section: Monte Carlo Simulationmentioning

confidence: 99%

See 1 more Smart Citation

Estimation and Evaluation of Tissue Inhomogeneity Effect on Dose Distribution for High Dose Rate Iridium 192 Source Using Monte Carlo Simulation and Film Dosimetery

Adelnia¹,

Fatehi²

2016

J Nucl Med Radiat Ther

View full text Add to dashboard Cite

The aim of this work was to present a theoretical analysis of how phantom dimensions and tissue heterogeneities in interstitial brachytherapy affect on dose distributions. This work was carried out using Gafchromic film measurement and Monte Carlo simulation for 192 Ir source. Results show that treatment planning systems (TPS) which consider the patient geometry as homogeneous medium, lead to a dose underestimation up to 8.2% for lung and an overestimation up to 9% for bone. These values depend on the thickness and distance from the source. Thus, TPSs currently in use for clinical brachytherapy cannot consider the effect of tissue heterogeneity on dose distribution.

show abstract

Section: Results Phantom Validationmentioning

confidence: 99%

Section: Monte Carlo Simulationmentioning

confidence: 99%

Estimation and Evaluation of Tissue Inhomogeneity Effect on Dose Distribution for High Dose Rate Iridium 192 Source Using Monte Carlo Simulation and Film Dosimetery

Adelnia¹,

Fatehi²

2016

J Nucl Med Radiat Ther

View full text Add to dashboard Cite

show abstract

“…In addition, the FTEs were developed to estimate the computational cost for transport and these variance-reduction techniques in the MCNP code. With that, [58,59] also demonstrate the effectiveness of this approach and a tool created to carry it out.…”

Section: Solomon Schultis Booth and Soodmentioning

confidence: 86%

“…In 2010, the history-score-moment equations were generalized by Solomon, Schultis, Booth, and Sood to treat weight-dependent variance-reduction techniques (most notably: weight windows) as described in [58,59]. Weight-dependent transport kernels for weight windows were derived (and other transport kernels for importance splitting, rouletting, weight cutoff, and implicit capture were re-derived).…”

Section: Solomon Schultis Booth and Soodmentioning

confidence: 99%

Cost-optimized Automated Variance Reduction for Highly Angle-dependent Radiation Transport Analyses [Dissertation]

2023

View full text Add to dashboard Cite

I appreciate Ms. Peggy Jo Gramer's and Dr. Garnette Roberts's ceaseless work to ensure that all needs, academic and personal, were addressed during my time as a doctoral student.My gratitude also goes to mentors from earlier in my career, Mr. Stan Anderson, Mr. Arnie Fero, and Dr. Gianluca Longoni, for instilling strong engineering principles and for encouraging me to follow a path that lead me to this point.

show abstract

“…However, Becker and Larsen showed that there is no rigorous mathematical link between the FOM and the Monte Carlo particle distribution, though the improvement in the FOM from a higher particle population is observable. Solomon et al 68 proposed a method to optimize the FOM by calculating the tally variance and the average computational time per history, thereby directly optimizing the FOM. This method is called the Cost Optimized Variance Reduction Technique (COVRT).…”

Section: Other Vr Methodsmentioning

confidence: 99%

Review of Hybrid Methods for Deep-Penetration Neutron Transport

Munk

Slaybaugh

2019

Nuclear Science and Engineering

View full text Add to dashboard Cite

Methods for deep-penetration radiation transport remain important for radiation shielding, nonproliferation, nuclear threat reduction, and medical applications. As these applications become more ubiquitous, the need for accurate and reliable transport methods appropriate for these systems persists. For such systems, hybrid methods often obtain reliable answers in the shortest time by leveraging the speed and uniform uncertainty distribution of a deterministic solution to bias Monte Carlo transport and reduce the variance in the solution. This work reviews the state of the art among such hybrid methods. First, we summarize variance reduction (VR) for Monte Carlo radiation transport and existing efforts to automate these techniques. Relations among VR, importance, and the adjoint solution of the neutron transport equation are then discussed. Based on this exposition, the work transitions from theory to a critical review of existing VR implementations in modern nuclear engineering software. At present, the Consistent Adjoint-Driven Importance Sampling (CADIS) and Forward-Weighted Consistent Adjoint-Driven Importance Sampling (FW-CADIS) hybrid methods are the gold standard by which to reduce the variance in problems that have deeply penetrating radiation. The CADIS and FW-CADIS methods use an adjoint scalar flux to generate VR parameters for Monte Carlo radiation transport. Additionally, efforts to incorporate angular information into VR methods for Monte Carlo are summarized. Finally, we assess various implementations of these methods and the degree to which they improve VR for their target applications.

show abstract

A Priori Deterministic Computational-Cost Optimization of Weight-Dependent Variance-Reduction Parameters for Monte Carlo Neutral-Particle Transport

Cited by 4 publications

References 7 publications

Estimation and Evaluation of Tissue Inhomogeneity Effect on Dose Distribution for High Dose Rate Iridium 192 Source Using Monte Carlo Simulation and Film Dosimetery

Estimation and Evaluation of Tissue Inhomogeneity Effect on Dose Distribution for High Dose Rate Iridium 192 Source Using Monte Carlo Simulation and Film Dosimetery

Cost-optimized Automated Variance Reduction for Highly Angle-dependent Radiation Transport Analyses [Dissertation]

Review of Hybrid Methods for Deep-Penetration Neutron Transport

Contact Info

Product

Resources

About