Vahid Badeli, Sascha Ranftl, Gian Marco Melito, Alice Reinbacher-Köstinger, Wolfgang Von Der Linden, Katrin Ellermann and Oszkar Biro
This paper aims to introduce a non-invasive and convenient method to detect a life-threatening disease called aortic dissection. A Bayesian inference based on enhanced…
Abstract
Purpose
This paper aims to introduce a non-invasive and convenient method to detect a life-threatening disease called aortic dissection. A Bayesian inference based on enhanced multi-sensors impedance cardiography (ICG) method has been applied to classify signals from healthy and sick patients.
Design/methodology/approach
A 3D numerical model consisting of simplified organ geometries is used to simulate the electrical impedance changes in the ICG-relevant domain of the human torso. The Bayesian probability theory is used for detecting an aortic dissection, which provides information about the probabilities for both cases, a dissected and a healthy aorta. Thus, the reliability and the uncertainty of the disease identification are found by this method and may indicate further diagnostic clarification.
Findings
The Bayesian classification shows that the enhanced multi-sensors ICG is more reliable in detecting aortic dissection than conventional ICG. Bayesian probability theory allows a rigorous quantification of all uncertainties to draw reliable conclusions for the medical treatment of aortic dissection.
Originality/value
This paper presents a non-invasive and reliable method based on a numerical simulation that could be beneficial for the medical management of aortic dissection patients. With this method, clinicians would be able to monitor the patient’s status and make better decisions in the treatment procedure of each patient.
Details
Keywords
Christian Magele, Michael Jaindl, Alice Köstinger, Werner Renhart, Bogdan Cranganu‐Cretu and Jasmin Smajic
The purpose of this paper is to extend a (μ/ρ, λ) evolution strategy to perform remarkably more globally and to detect as many solutions as possible close to the Pareto optimal…
Abstract
Purpose
The purpose of this paper is to extend a (μ/ρ, λ) evolution strategy to perform remarkably more globally and to detect as many solutions as possible close to the Pareto optimal front.
Design/methodology/approach
A C‐link cluster algorithm is used to group the parameter configurations of the current population into more or less independent clusters. Following this procedure, recombination (a classical operator of evolutionary strategies) is modified. Recombination within a cluster is performed with a higher probability than recombination of individuals coming from detached clusters.
Findings
It is shown that this new method ends up virtually always in the global solution of a multi‐modal test function. When applied to a real‐world application, several solutions very close to the front of Pareto optimal solutions are detected.
Research limitations/implications
Stochastic optimization strategies need a very large number of function calls to exhibit their ability to reach very good local if not the global solution. Therefore, the application of such methods is still limited to problems where the forward solutions can be obtained with a reasonable computational effort.
Originality/value
The main improvement is the usage of approximate number of isolated clusters to dynamically update the size of the population in order to save computation time, to find the global solution with a higher probability and to use more than one objective function to cover a larger part of the Pareto optimal front.
Details
Keywords
Werner Renhart, Mario Bellina, Christian Magele and Alice Köstinger
The purpose of this paper is to achieve a very accurate localization of hidden metallic objects in human medicine applications.
Abstract
Purpose
The purpose of this paper is to achieve a very accurate localization of hidden metallic objects in human medicine applications.
Design/methodology/approach
The proposed methodology takes advantage of the eddy current effect within a metallic object. Its magnetic reaction field will be measured, e.g. with giant magnetic resistor (GMR) sensors.
Findings
A comparison of measurements and numerical results obtained by finite element computations demonstrate the reliability and positively gives a clue about the feasibility of the suggested method.
Research limitations/implications
While measuring noisy signals, the use of a lock‐in amplifier is rather expensive; especially, in applications with a high number of GMR sensors the use of channel multiplexer must be considered, which again may generate noise.
Originality/value
The paper shows how appropriate shielding of external fields in the measurement setup ensures results of satisfying quality.