PH-0545 Daily and accumulated dose based on residual errors for pancreas SABR using two different approaches

2021 ◽  
Vol 161 ◽  
pp. S428-S429
Author(s):  
Y. Ez-zyouy ◽  
A. Gulyban ◽  
C. Bouchart ◽  
N. Reynaert
Keyword(s):  
Residual Errors ◽  
Accumulated Dose

scholarly journals Adaptive planning based on single beam optimization in passive scattering carbon ion radiotherapy for patients with pancreatic cancer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Yang Li ◽  
Yoshiki Kubota ◽  
Masahiko Okamoto ◽  
Shintaro Shiba ◽  
Shohei Okazaki ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Carbon Ion Radiotherapy ◽  
Adaptive Planning ◽  
Carbon Ion ◽  
Single Beam ◽  
Original Plan ◽  
Image Registration Algorithm ◽  
Passive Scattering ◽  
Accumulated Dose ◽  
Dose Difference

Abstract Background Daily anatomical deviations may distort the dose distribution in carbon ion radiotherapy (CIRT), which may cause treatment failure. Therefore, this study aimed to perform re-planning to maintain the dose coverage in patients with pancreatic cancer with passive scattering CIRT. Methods Eight patients with pancreatic cancer and 95 daily computed tomography (CT) sets were examined. Two types of adaptive plans based on new range compensators (RCs) (AP-1) and initial RCs (AP-2) were generated. In AP-2, each beam was optimized by manually adjusting the range shifter thickness and spread-out Bragg peak size to make dose reduction by < 3% of the original plan. Doses of the original plan with bone matching (BM) and tumor matching (TM) were examined for comparison. We calculated the accumulated dose using the contour and intensity-based deformable image registration algorithm. The dosimetric differences in respect to the original plan were compared between methods. Results Using TM and BM, mean ± standard deviations of daily CTV V95 (%) difference from the original plan was − 5.1 ± 6.2 and − 8.8 ± 8.8, respectively, but 1.2 ± 3.4 in AP-1 and − 0.5 ± 2.1 in AP-2 (P < 0.001). AP-1 and AP-2 enabled to maintain a satisfactory accumulated dose in all patients. The dose difference was 1.2 ± 2.8, − 2,1 ± 1.7, − 7.1 ± 5.2, and − 16.5 ± 15.0 for AP-1, AP-2, TM, and BM, respectively. However, AP-2 caused a dose increase in the duodenum, especially in the left–right beam. Conclusions The possible dose deterioration should be considered when performing the BM, even TM. Re-planning based on single beam optimization in passive scattering CIRT seems an effective and safe method of ensuring the treatment robustness in pancreatic cancer. Further study is necessary to spare healthy tissues, especially the duodenum.

scholarly journals Improvement of Heavy Load Robot Positioning Accuracy by Combining a Model-Based Identification for Geometric Parameters and an Optimized Neural Network for the Compensation of Nongeometric Errors

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Yuxiang Wang ◽  
Zhangwei Chen ◽  
Hongfei Zu ◽  
Xiang Zhang ◽  
Chentao Mao ◽  
...  
Keyword(s):  
Neural Network ◽  
Manufacturing Systems ◽  
Robot Manipulator ◽  
Joint Stiffness ◽  
Calibration Method ◽  
Geometric Parameters ◽  
Heavy Load ◽  
Positioning Accuracy ◽  
Robot Positioning ◽  
Residual Errors

The positioning accuracy of a robot is of great significance in advanced robotic manufacturing systems. This paper proposes a novel calibration method for improving robot positioning accuracy. First of all, geometric parameters are identified on the basis of the product of exponentials (POE) formula. The errors of the reduction ratio and the coupling ratio are identified at the same time. Then, joint stiffness identification is carried out by adding a load to the end-effector. Finally, residual errors caused by nongeometric parameters are compensated by a multilayer perceptron neural network (MLPNN) based on beetle swarm optimization algorithm. The calibration is implemented on a SIASUN SR210D robot manipulator. Results show that the proposed method possesses better performance in terms of faster convergence and higher precision.

Urban travel demand: The impact of Box-Cox transformations with nonspherical residual errors

1987 ◽  
Vol 21 (6) ◽  
pp. 443-477 ◽  
Author(s):  
Marcel G. Dagenais ◽  
Marc J.I. Gaudry ◽  
Tran Cong Liem
Keyword(s):  
Travel Demand ◽  
Urban Travel ◽  
The Impact ◽  
Residual Errors

PD-0554: CTV-to-PTV margin assessment for esophageal cancer radiotherapy based on accumulated dose analysis

2020 ◽  
Vol 152 ◽  
pp. S308
Author(s):  
M. Boekhoff ◽  
I. Defize ◽  
A. Kotte ◽  
N. Takahashi ◽  
J. Lagendijk ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Margin Assessment ◽  
Cancer Radiotherapy ◽  
Ptv Margin ◽  
Accumulated Dose

scholarly journals Articulation Rate and Speech-Sound Normalization Failure

2003 ◽  
Vol 46 (3) ◽  
pp. 724-737 ◽  
Author(s):  
Peter Flipsen
Keyword(s):  
Speech Sound ◽  
Unknown Origin ◽  
Preschool Age ◽  
Test Time ◽  
Motor Deficits ◽  
Conversational Speech ◽  
Articulation Rate ◽  
Outcome Group ◽  
Residual Errors

Not all children with speech delay (SD) of unknown origin develop fully normal speech even with intervention. Many retain residual distortion errors into adolescence and ultimately into adulthood. The current study examined whether articulation rate distinguishes those children who retain residual errors from those who normalize. Two groups of speech-delayed children originally identified at preschool age were retested at age 9 years (the early follow-up group) and at age 12–16 years (the late follow-up group), respectively. No differences in articulation rate were observed at either test time in conversational speech between those children who continued to produce residual distortion errors (RE) compared to those children who had fully normalized speech (NSA). For the late follow-up group, children in the RE outcome group articulated speech at significantly slower rates than the children in the NSA outcome group in an embedded words task using both syllables per second and phones per second measures. Findings suggested that children with SD of unknown origin who fail to normalize may have relative speech-motor deficits and possibly deficits in language formulation skill. Alternatively, slower articulation rate in structured tasks may represent some sort of compensation for the continuing presence of speech-sound errors. Possible motivations for such compensation are discussed.

An individualized strategy to estimate the effect of deformable registration uncertainty on accumulated dose in the upper abdomen

2018 ◽  
Vol 63 (12) ◽  
pp. 125005 ◽  
Author(s):  
Yibing Wang ◽  
Steven F Petit ◽  
Eliana Vásquez Osorio ◽  
Vikas Gupta ◽  
Alejandra Méndez Romero ◽  
...  
Keyword(s):  
Deformable Registration ◽  
Upper Abdomen ◽  
Accumulated Dose

scholarly journals Analytical solutions to contact problem with fractional derivatives in the sense of Caputo

2020 ◽  
Vol 24 (Suppl. 1) ◽  
pp. 313-323
Author(s):  
Muhammad Noor ◽  
Muhammad Rafiq ◽  
Salah-Ud-Din Khan ◽  
Muhammad Qureshi ◽  
Muhammad Kamran ◽  
...  
Keyword(s):  
Boundary Value Problem ◽  
Iteration Method ◽  
Boundary Value ◽  
Variational Iteration Method ◽  
Contact Problems ◽  
Function Technique ◽  
Fractional Boundary Value Problem ◽  
Variational Iteration ◽  
Residual Errors ◽  
Fractional Boundary Value Problems

The current study extends the applications of the variational iteration method for the analytical solution of fractional contact problems. The problem involves Caputo sense while calculating the derivative of fractional order, we apply the Penalty function technique to transform it into a system of fractional boundary value problems coupled with a known obstacle. The variational iteration method is employed to find the series solution of fractional boundary value problem. For different values of fractional parameters, residual errors of solutions are plotted to make sure the convergence and accuracy of the solution. The reasonably accurate results show that one of the highly effective and stable methods for the solution of fractional boundary value problem is the method of variational iteration.

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