[1] Zhou Zhengdong, Chen Yuanhua, Wang Dongdong, Yu Zili, et al. Reconstruction of the linac photon spectrumbased on prior knowledge and the genetic algorithm [J]. Journal of Southeast University (English Edition), 2014, 30 (3): 311-314. [doi:10.3969/j.issn.1003-7985.2014.03.010]

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Reconstruction of the linac photon spectrumbased on prior knowledge and the genetic algorithm()

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Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]

Volumn:

30

Issue:

2014 3

Page:

311-314

Research Field:

Computer Science and Engineering

Publishing date:

2014-09-30

Info

Title:

Reconstruction of the linac photon spectrumbased on prior knowledge and the genetic algorithm

Author(s):

Zhou Zhengdong;  Chen Yuanhua;  Wang Dongdong;  Yu Zili

Department of Nuclear Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China

Keywords:

reconstruction of the photon spectrum;  prior knowledge;  genetic algorithm(GA);  percent depth dose(PDD);  Monte Carlo simulation

PACS:

TP391;R318

DOI:

10.3969/j.issn.1003-7985.2014.03.010

Abstract:

In order to derive the linac photon spectrum accurately, both the prior constrained model and the genetic algorithm(GA)are employed using the measured percentage depth dose(PDD)data and the Monte Carlo simulated monoenergetic PDDs, where two steps are involved. First, the spectrum is modeled as a prior analytical function with two parameters α and E_p optimized with the GA. Secondly, the linac photon spectrum is modeled as a discretization constrained model optimized with the GA. The solved analytical function in the first step is used to generate initial solutions for the GA’s first run in this step. The method is applied to the Varian iX linear accelerator to derive the energy spectra of its 6 and 15 MV photon beams. The experimental results show that both the reconstructed spectrums and the derived PDDs with the proposed method are in good agreement with those calculated using the Monte Carlo simulation.

References:

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Memo

Memo:

Biography: Zhou Zhengdong(1969—), male, doctor, associate professor, zzd_-msc@nuaa.edu.cn.
Citation: Zhou Zhengdong, Chen Yuanhua, Wang Dongdong, et al. Reconstruction of the linac photon spectrum based on prior knowledge and the genetic algorithm[J].Journal of Southeast University(English Edition), 2014, 30(3):311-314.[doi:10.3969/j.issn.1003-7985.2014.03.010]

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