A COMPARISON OF PARTICLE FILTER ALGORITHMS APPLIED TO THE TEMPERATURE FIELD ESTIMATION IN HYPERTHERMIA PHANTOMS

Author(s):  
Bernard Lamien ◽  
Helcio R. B. Orlande ◽  
Guillermo Elicabe
2006 ◽  
Vol 6 (3) ◽  
pp. 397-405
Author(s):  
M. Celano ◽  
P. P. Alberoni ◽  
V. Levizzani ◽  
A. R. Holt

Abstract. The recent gradual increase in the use of polarimetric radars prompts for possible improvements in the estimation of precipitation and the identification of the prevailing hydrometeor type. An analysis of different convection episodes (20 May 2003, 4 and 7 May 2004) is conducted in order to explore the attenuation effects at C band and their consequences on the rainfall field estimation using two polarimetric radars in the Po Valley, Italy, located about 90 km apart. A hydrometeor classification scheme, developed at the National Severe Storms Laboratory (NSSL), is used to detect the microphysical structure of the different cloud systems. The work is focused on the reconstruction of the 3-D organisation of the convective events, highlighting how the two radar systems ''see'' the storms from different points of view. Furthermore, the two distinct observations and the temperature field are used to correct the effect of attenuation.


Energies ◽  
2017 ◽  
Vol 10 (8) ◽  
pp. 1149 ◽  
Author(s):  
Bizhong Xia ◽  
Zhen Sun ◽  
Ruifeng Zhang ◽  
Deyu Cui ◽  
Zizhou Lao ◽  
...  

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
S. Prasanna ◽  
S. P. Venkateshan

A new methodology based on least-squares approach has been developed to estimate the temperature field from an interferogram recorded using a Differential interferometer (DI). The interferograms are digitally evaluated using two dimensional Fourier transforms to retrieve the temperature gradient field. Temperature field is constructed by fitting a cubic spline to the first derivatives data. The methodology has been applied to both experimental and synthetic interferograms. Both convective heat flux and temperature field were predicted accurately. The role of image noise and errors in the temperature measurements on the temperature field estimation have been studied with the aid of synthetic interferograms.


Author(s):  
Bernard Lamien ◽  
Leonardo A.B. Varon ◽  
Helcio R.B. Orlande ◽  
Guillermo E. Elicabe

Purpose The purpose of this paper is to focus on applications related to the hyperthermia treatment of cancer, with heating imposed either by a laser in the near-infrared range or by radiofrequency waves. The particle filter algorithms are compared in terms of computational time and solution accuracy. Design/methodology/approach The authors extend the analyses performed in their previous works to compare three different algorithms of the particle filter, as applied to the hyperthermia treatment of cancer. The particle filters examined here are the sampling importance resampling (SIR) algorithm, the auxiliary sampling importance resampling (ASIR) algorithm and Liu & West’s algorithm. Findings Liu & West’s algorithm resulted in the largest computational times. On the other hand, this filter was shown to be capable of dealing with very large uncertainties. In fact, besides the uncertainties in the model parameters, Gaussian noises, similar to those used for the SIR and ASIR filters, were added to the evolution models for the application of Liu & West’s filter. For the three filters, the estimated temperatures were in excellent agreement with the exact ones. Practical implications This work may help medical doctors in the future to prescribe treatment protocols and also opens the possibility of devising control strategies for the hyperthermia treatment of cancer. Originality/value The natural solution to couple the uncertain results from numerical simulations with the measurements that contain uncertainties, aiming at the better prediction of the temperature field of the tissues inside the body, is to formulate the problem in terms of state estimation, as performed in this work.


Author(s):  
Yuiko Koga ◽  
◽  
Akiyoshi Yamamoto ◽  
Hyoungseop Kim ◽  
Joo Kooi Tan ◽  
...  

Recently, the arteries sclerosis obliterans (ASO) or called peripheral arterial disease (PAD) typically caused by chronic ischemia of limbs increases remarkably. As one of the diagnosis methods, the image diagnosis methods such as MR image are applied in medical fields. In this paper, we propose a vascular extraction method using fresh blood imaging (FBI) method, as well as apply it to computer aided diagnosis (CAD) system. Especially, to prevent the spread outside of the region and improve the segment accuracy of peripheral artery areas, we introduce particle filter algorithms. We performed our method on automatic artery regions detection using non-enhanced MR images. Furthermore, we compared the extracted results to gold standard data and analyzed accuracy by receiver operating characteristic (ROC). The effectiveness of our proposed method and satisfactory of its detected accuracy were confirmed.


Sign in / Sign up

Export Citation Format

Share Document