scholarly journals Feasibility of large volume tumor ablation using multiple-mode strategy with fast scanning method: A numerical study

2017 ◽  
Author(s):  
Hao Wu ◽  
Guofeng Shen ◽  
Shan Qiao ◽  
Yazhu Chen
Keyword(s):  
Large Volume ◽  
Numerical Study ◽  
Tumor Ablation ◽  
Scanning Method ◽  
Multiple Mode

Contact Residue for Simultaneous Removal of Vehicle’s Frequency and Surface Roughness in Scanning Bridge Frequencies Using Two Connected Vehicles

2021 ◽  
pp. 2171006
Author(s):  
Y. B. Yang ◽  
X. Q. Mo ◽  
K. Shi ◽  
Z. L. Wang ◽  
H. Xu ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Numerical Study ◽  
Contact Point ◽  
Connected Vehicles ◽  
Scanning Method ◽  
Contact Residue ◽  
Two Factors ◽  
Vehicle Response ◽  
Residual Response ◽  
Contact Response

Two factors are critical to the effectiveness of the vehicle scanning method for bridge frequencies. One is the frequency of the test vehicle itself. This can be eliminated by using the vehicle–bridge contact point response calculated from the vehicle response. The other is the surface roughness of the bridge, which can be removed by using the residual response of two connected vehicles. In this paper, it is demonstrated for the first time that both vehicle’s frequency and surface roughness can be simultaneously eliminated using the contact residue of two connected vehicles. Theoretically, a formulation is presented for both the contact response and residues. In the numerical study, the contact response is demonstrated to outperform the vehicle response as more bridge frequencies can be identified, while the contact residue is verified to work well for various surface roughnesses, vehicle spacings, and bridge damping ratios. For damped bridges with rough surfaces, the contact residue enables us to extract the first three bridge frequencies.

scholarly journals Calorimetric Non-Destructive Assay of Large Volume and Heterogeneous Radioactive Waste Drums

2020 ◽  
Vol 225 ◽  
pp. 06003
Author(s):  
W. R. Kubinski ◽  
C. Carasco ◽  
D. Kikola ◽  
C. Mathonat ◽  
D. Ricard ◽  
...  
Keyword(s):  
Radioactive Waste ◽  
Large Volume ◽  
Energy Deposition ◽  
Particle Flux ◽  
Background Radiation ◽  
Numerical Study ◽  
High Energy ◽  
Beta Emitters ◽  
Non Destructive ◽  
Waste Drums

The EU-CHANCE project aims at the issue of the characterization of conditioned radioactive waste (CRW) and one objective of CHANCE is to focus on: Calorimetry as a comprising non-destructive technique to reduce uncertainties on the inventory of radwaste containing shielded and hidden material difficult to be measured by other means. A MCNP6-based numerical study comprising the particle flux out of a 200L mock-up drum in a Large Volume Calorimeter (LVC) currently manufactured by KEP Nuclear (France) will be presented and discussed. For the analyses, the particle flux and energy deposition in each layer of the calorimeter were determined. The results yield that a significant fraction of the radiation would leave the system and not contribute to the measurable heat deposition. The expected energy deposition is obtained and cumulated for each layer over the whole energy range revealing the fraction of particles actually escaping the LVC calorimeter. While this escape fraction needs and can be determined, the LVC is a very suitable apparatus for the anticipated experiments on large and heterogeneous waste drums that possibly contain deeply buried beta-emitters (e.g. Sr/Y-90) or shielded alpha-sources hidden inside the drum with a significant level of gamma and neutron radiation background radiation. The high-energy part of this gamma and neutron flux may even reach the reference chamber of the calorimeter and deposit some energy there, compromising the calibration and may cause a double-bias.

Treatment Planning Optimization in Irreversible Electroporation for Complete Ablation of Variously Sized Cervical Tumors: A Numerical Study

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Lujia Ding ◽  
Michael Moser ◽  
Yigang Luo ◽  
Wenjun Zhang ◽  
Bing Zhang
Keyword(s):  
Numerical Study ◽  
Irreversible Electroporation ◽  
Tumor Ablation ◽  
Optimization Approach ◽  
Nsga Ii ◽  
Problem Model ◽  
Normal Tissues ◽  
Planning Optimization ◽  
Decision Variables ◽  
Cervical Tumors

Abstract Irreversible electroporation (IRE), a relatively new energy-based tumor ablation technology, has shown itself in the last decade to be able to safely ablate tumors with favorable clinical outcomes, yet little work has been done on optimizing the IRE protocol to variously sized tumors. Incomplete tumor ablation has been shown to be the main reason leading to the local recurrence and thus treatment failure. The goal of this study was to develop a general optimization approach to optimize the IRE protocol for cervical tumors in different sizes, while minimizing the damage to normal tissues. This kind of approach can lay a foundation for future personalized treatment of IRE. First, a statistical IRE cervical tumor death model was built using previous data in our group. Then, a multi-objective optimization problem model was built, in which the decision variables are five IRE-setting parameters, namely, the pulse strength (U), the length of active tip (H), the number of pulses delivered in one round between a pair of electrodes (A), the distance between electrodes (D), and the number of electrodes (N). The domains of the decision variables were determined based on the clinical experience. Finally, the problem model was solved by using nondominated sorting genetic algorithms II (NSGA-II) algorithm to give respective optimal protocol for three sizes of cervical tumors. Every protocol was assessed by the evaluation criterion established in the study to show the efficacy in a more straightforward way. The results of the study demonstrate this approach can theoretically provide the optimal IRE protocol for different sizes of tumors and may be generalizable to other types, sizes, and locations of tumors.

Scanning ion microscopy images

1987 ◽  
Vol 45 ◽  
pp. 180-181
Author(s):  
R. Levi-Setti ◽  
J.M. Chabala ◽  
Y.L. Wang
Keyword(s):  
Metal Ion ◽  
Secondary Emission ◽  
Scanning Method ◽  
Ion Channeling ◽  
Secondary Ions ◽  
High Resolution Images ◽  
Ion Microscopy ◽  
Z Contrast ◽  
Focused Beams ◽  
Microscopy Images

Finely focused beams extracted from liquid metal ion sources (LMIS) provide a wealth of secondary signals which can be exploited to create high resolution images by the scanning method. The images of scanning ion microscopy (SIM) encompass a variety of contrast mechanisms which we classify into two broad categories: a) Emission contrast and b) Analytical contrast.Emission contrast refers to those mechanisms inherent to the emission of secondaries by solids under ion bombardment. The contrast-carrying signals consist of ion-induced secondary electrons (ISE) and secondary ions (ISI). Both signals exhibit i) topographic emission contrast due to the existence of differential geometric emission and collection effects, ii) crystallographic emission contrast, due to primary ion channeling phenomena and differential oxidation of crystalline surfaces, iii) chemical emission or Z-contrast, related to the dependence of the secondary emission yields on the Z and surface chemical state of the target.

Selected Abstracts of Recent Research in Stuttering

1999 ◽  
Vol 9 (1) ◽  
pp. 5-6
Author(s):  
Carrie Bain ◽  
Nan Bernstein Ratner
Keyword(s):  
Large Volume ◽  
Clinical Relevance

Due to the large volume of fluency-related publications since the last column, we have chosen to highlight those articles of highest potential clinical relevance.

Intraoperative abdominal ultrasonography-guided large volume ethanol injection for hepatocellular carcinoma

2001 ◽  
Vol 120 (5) ◽  
pp. A482-A482
Author(s):  
R MONDRAGONSANCHEZ ◽  
A GARDUOLOPEZ ◽  
H MURRIETA ◽  
M FRIASMENDIVIL ◽  
R ESPEJO ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Large Volume ◽  
Abdominal Ultrasonography ◽  
Ethanol Injection

1511: Is Transurethral Resection Safe and Efficacious for Men with Large Volume Prostates

2006 ◽  
Vol 175 (4S) ◽  
pp. 488-488
Author(s):  
Frédéric Michel ◽  
Jad Watfa ◽  
Thomas Dubruille
Keyword(s):  
Large Volume ◽  
Transurethral Resection

Numerical study of the low-frequency atomic dynamics in a Lennard-Jones glass

1998 ◽  
Vol 77 (2) ◽  
pp. 473-484 ◽  
Author(s):  
M. Sampoli, P. Benassi, R. Dell'Anna,
Keyword(s):  
Numerical Study ◽  
Low Frequency ◽  
Lennard Jones
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