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1
Content available remote Data analysis system for surface potential of biological tissues
Hyka Oleksii, Vejar Andres, Rymarczyk Tomasz
Przegląd Elektrotechniczny
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2022
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R. 98, nr 5
157--160
EN
A portable low-power monitoring system for measuring surface biopotential and data processing is presented. The small device was designed using hardware and codesign. The system is based on a microcircuit consisting of a field-programmable gate array device and a dual-core microcontroller. The selected reconfigurable hardware provides the desired level of speed and accuracy combined with low power consumption for online data processing applications. Spectroscopy impedance measurements are used to analyze the electrical properties of biological tissue.
PL
Przedstawiono przenośny system monitorowania o niskim poborze mocy do pomiaru biopotencjału powierzchniowego i przetwarzania danych. Małe urządzenie zostało zaprojektowane z wykorzystaniem projektowania sprzętowego i kodowego. System oparty jest na mikroukładzie składającym się z programowalnej matrycy bramek oraz dwurdzeniowego mikrokontrolera. Wybrany rekonfigurowalny sprzęt zapewnia pożądany poziom szybkości i dokładności w połączeniu z niskim zużyciem energii dla aplikacji przetwarzania danych online. Pomiary impedancji w spektroskopii są wykorzystywane do analizy właściwości elektrycznych tkanki biologicznej.
2
Content available remote Processing multispectral images of the surface of biotissues using fuzzy logic
Petrov Oleksandr
Przegląd Elektrotechniczny
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2020
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R. 96, nr 12
71--75
EN
The method uses multispectral image segmentation based on measuring diffuse reflection coefficients at certain wavelengths of spectral channels, solving the inverse optical problem of determining the concentrations of hemoglobin destruction products in the near-surface biotissues, filtering and segmentation of the image, calculating the relative sizes of segments and determination of damages using fuzzy logic.
PL
Metoda wykorzystuje wielospektralną segmentację obrazu opartą na pomiarze współczynników odbicia rozproszonego przy określonych długościach fali kanałów widmowych, rozwiązując odwrotny problem optyczny określania stężeń produktów niszczenia hemoglobiny w biotekstach powierzchniowych, filtrowania i segmentacji obrazu, obliczania względnych rozmiarów segmentów i określanie uszkodzeń za pomocą logiki rozmytej.
3
Content available remote Instance Segmentation Model Created from Three Semantic Segmentations of Mask, Boundary and Centroid Pixels Verified on GlaS Dataset
Malík Peter, Krištofík Štefan, Knapová Kristína
Annals of Computer Science and Information Systems
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2020
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Vol. 21
569--576
EN
Segmentation is the key computer vision task in modern medicine applications. Instance segmentation became the prevalent way to improve segmentation performance in recent years. This work proposes a novel way to design an instance segmentation model that combines 3 semantic segmentation models dedicated for foreground, boundary and centroid predictions. It contains no detector so it is orthogonal to a standard instance segmentation design and can be used to improve the performance of a standard design. The presented custom designed model is verified on the Gland Segmentation in Colon Histology Images dataset.
4
Content available remote Acoustic excitation of electric field in water solution NaCl
Avrunin Oleg G., Bondarenko Igor S., Bondarenko Stanislav I., Kuzmenko Yulia V., Pinaieva Olga Yu., Kisała Piotr, Tleshova Akmaral, Luganskaya Saule
Przegląd Elektrotechniczny
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2019
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R. 95, nr 4
158--161
EN
The electric field value has been measured in an electroconducting water solution with NaCl, arising at simultaneously action on it of ultrasound and a direct magnetic field. Basic approaches and scheme of the laboratory device are proposed and designed. The basic characteristics of ultrasonic radiation in a place of measurement of electric field are defined, proceeding from its value and the experimental installation parameters. It is possible to assume, that at constant values of intensity of radiation and a magnetic field the value of measured voltage in the set areas of a body will give the new quantitative information on an organism state. Possibility of use of measurements of electric field for studying of properties of the biological tissue is discussed.
PL
Wartość pola elektrycznego została zmierzona w elektroprzewodzącym roztworze wodnym z NaCl, powstającym przy równoczesnym oddziaływaniu na nie ultradźwiękami i bezpośrednim polem magnetycznym. Zaproponowano i zaprojektowano podstawowe podejścia i schemat urządzenia laboratoryjnego. Określono podstawowe właściwości promieniowania ultradźwiękowego w miejscu pomiaru pola elektrycznego, wychodząc z jego wartości i eksperymentalnych parametrów instalacji. Można założyć, że przy stałych wartościach natężenia promieniowania i pola magnetycznego wartość mierzonego napięcia w zadanych obszarach ciała da nową informację ilościową o stanie organizmu. Omówiono możliwości wykorzystania pomiarów pola elektrycznego do badania właściwości tkanki biologicznej.
5
Content available remote Multispectral method and means for determining the distance of the shot on the basis of the study of gunshot injuries of the skin tissues
Petruk V., Kvaternyuk S., Kvaternyuk O., Mokanyuk O., Petruk R., Mussubekov R., Wójcik W., Toigozhinova A., Kalizhanova A.
Przegląd Elektrotechniczny
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2017
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R. 93, nr 3
129--132
EN
The work carried out research and development of methods and means of multispectral vision measurement control and diagnosing of parameters of inhomogeneous biological media for biomedical diagnostics with the use of the n-dimensional multispectral data for each pixel of the array of digital images obtained by the CCD camera. Application results can use to diagnose the nature and severity of gunshot injuries to the biomannequins, biological and physiological properties of the skin tissues that are close to the morphological and functional characteristics of human.
PL
W pracy przedstawiono badania oraz opracowanie metod i środków multispektralnych pomiarów wizyjnych i diagnozowania parametrów niejednorodnych mediów biologicznych dla diagnostyki biomedycznej z wykorzystaniem wielospektralnych n-wymiarowych danych dla każdego piksela tablicy cyfrowych obrazów uzyskanych z aparatu z matrycą CCD. Wyniki aplikacji mogą być użyte, do diagnozowania rodzaju i skali obrażeń postrzałowych bio-manekinów, właściwości biologicznych i fizjologicznych tkanek skóry, zbliżonych do ludzkich cech morfologicznych i funkcjonalnych.
6
Content available remote Governing Differential Equations for the Mechanics of Undamageable Materials
Voyiadjis G. Z., Kattan P. I.
Engineering Transactions
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2014
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Vol. 62, iss. 3
241–-267
EN
In this work the mathematical foundations of the mechanics of elastic undamageable materials are presented. In particular the governing differential equations are derived for both the scalar and tensorial cases. In the isotropic case it is found that the resulting scalar differential equations are simple and easy to solve. However, in the anisotropic case the tensorial differential equations are complicated and unsolvable at this time. The current work presents the solution in the form of explicit nonlinear stress-strain relations for the simple one-dimensional case. However, the general solution of the three-dimensional case remains unattainable at the present time. Only the governing tensorial differential equations are derived for this latter case. It is to be noted that the term “undamageable” is reflected in the context of the material stiffness and not the property of indestructibility due to various loading conditions. Thus, the undamageable material reflects that no microcracks or microvoids occur as well as no plastic yielding in the material. To illustrate this concept, a last section is added on applications.
7
Content available remote Modeling of temperature field inside the tissue with a blood vessel using the BEM-FDM algorithm
Majchrzak E., Borowska J., Klekot J., Tarasek D.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2012
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Vol. 11, nr 4
85-92
EN
The thermal interactions between the blood vessel and surrounding biological tissue are analyzed. The tissue temperature is described by the Pennes equation, while the equation determining the change of blood temperature along the blood vessel is formulated on the basis of adequate energy balance. These equations are coupled by a boundary condition given at the blood vessel wall. The problem is solved using the hybrid algorithm, this means the temperature field in biological tissue is determined by means of the boundary element method (BEM), while the blood temperature is determined by means of the finite difference method (FDM). In the final part the examples of computations are presented.
8
Content available remote Sensitivity of tissue freezing process on changes of time-dependent cryoprobe tip cooling rate
Mochnacki B., Siedlecki J.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2011
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Vol. 10, nr 2
191-197
EN
In the paper, the problems of thermal interactions between skin tissue and a cylindrical cryoprobe tip are discussed. The cryoprobe tip temperature is time-dependent and its changes from the initial temperature to the final one and back are assumed in the form of a broken line (successive sectors correspond to cooling and heating processes or cooling and heating ones divided by a horizontal sector (a constant freezing temperature)). The aim of the considerations resolves itself in the analysis of dependences between the tip cooling (heating) rate and the course of the freezing process. To solve the problem, the direct approach of sensitivity analysis is used. The mathematical model of freezing is based on the energy equation corresponding to the 'fixed domain method' in which a parameter called 'the substitute thermal capacity' appears. The sensitivity model results from the differentiation of energy equation and boundary-initial conditions with respect to the cooling (heating) rate. At the stage of computations, the finite differences method (FDM) is used. In the final part of paper, examples of computations are presented.
9
Content available remote Numerical analysis of heat transfer in countercurrent blood flow and biological tissue
Majchrzak E., Tarasek D.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2011
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Vol. 10, nr 2
143-153
EN
Bioheat transfer in biological tissue is described by the Pennes equation, while the change of blood temperature along the artery and vein is described by ordinary differential equations, at the same time the countercurrent blood flow is taken into account. The coupling of these equations results from the boundary conditions given by the blood vessel walls. There are two methods used here in order to calculate the temperatures along the blood vessels and across biological tissue. To solve the Pennes equation, the Multiple Reciprocity Boundary Element Method (MRBEM) is applied. It should be pointed out that this method does not require discretisation of the interior of the domain. The second method used in this paper is the Finite Difference Method (FDM) and it is applied to calculate the temperatures along the blood vessels, and it complements the previous one. It is important to note that the diameter of an artery is smaller than of a vein, which results from the physiological characteristics of these blood vessels. In the final part of the paper, the results of the computations are shown and conclusions are formulated.
10
Content available remote Application of BEM for numerical solution of thermal wave model of bioheat transfer
Kałuża G., Ładyga E.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2011
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Vol. 10, nr 1
83-91
EN
The thermal wave model of bioheat transfer supplemented by boundary and initial conditions is considered. To solve the problem, the boundary element method (BEM) is proposed. In the final part of the paper examples of numerical computations concerning the determination of the temperature field in a heating tissue are shown.
11
Content available remote Numerical modelling of tissue heating by means of the electromagnetic field
Majchrzak E., Paruch M.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2010
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Vol. 9, nr 1
89-97
EN
Electromagnetic field induced by two external electrodes and temperature field resulting from electrodes action in 3D domain of biological tissue is considered. External electric field causes the heat generation in tissue domain. The distribution of electric potential in domain considered is described by the Laplace equation, while the temperature field is described by the Pennes equation. These problems are coupled by source function being the additional component in Pennes equation and resulting from the electric field action. The boundary element method is applied to solve the coupled problem connected with the biological tissue heating. In the final part of the paper the examples of computations are shown.
12
Content available remote Numerical modeling of tissue coagulation during laser irradiation controlled by surface temperature
Jasiński M.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2010
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Vol. 9, nr 1
29-36
EN
The numerical analysis of thermal process proceeding in biological tissue during a laser irradiation controlled by surface temperature of tissue is presented. Heat transfer in the tissue is assumed to be transient and one-dimensional. The internal heat sources resulting from laser irradiation based on the Beer law are taken into account. Perfusion rate and effective scattering coefficient are treated as dependent on tissue injury. At the stage of numerical computations the boundary element method has been used. In the final part of paper the results obtained are shown.
13
Content available remote Numerical modeling of heat transfer in a single blood vessel and surrounding biological tissue
Majchrzak E., Tarasek D.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2010
|
Vol. 9, nr 2
145-152
EN
The thermal interactions between the single blood vessel and surrounding biological tissue are analyzed. The temperature in the tissue is described by the Pennes equation, while the equation determining the change of blood temperature along the blood vessel is formulated on the basis of adequate energy balance. These equations are coupled by boundary condition given at the blood vessel wall. There are two models considered here in terms of blood vessel types. First is the supplying vessel model and the other one is traversing vessel model. Both are distinguished in the computations. The solution of the problem has been provided by means of finite difference method.
14
Content available remote Influence of cryoprobe cooling/heating rate on the course of freezing process
Mochnacki B., Siedlecki J., Tuzikiewicz W.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2010
|
Vol. 9, nr 2
197-202
EN
The methods of sensitivity analysis are used in order to observe the influences of changes of the cryoprobe tip cooling/heating rate on a course of biological tissue freezing process. The temperature history of tip temperature is assumed in a form of broken line. The direct variant of sensitivity analysis is here applied. At the stage of numerical modeling the control volume method is used. In the final part of the paper the examples of computations are shown.
15
Content available remote Application of the boundary element method coupled with the artificial heat source procedure for numerical modelling of freezing process
Majchrzak E., Dziewoński M., Kałuża G.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2009
|
Vol. 8, nr 1
105-112
EN
The freezing process of biological tissue subjected to the action of external cylindrical cryoprobe is analyzed. From the mathematical point of view the problem belongs to the group of moving boundary ones because the shape and dimensions of frozen region are time dependent. In the paper the mathematical model of the process considered and the method of solution are presented. Next, the example of computations is shown.
16
Content available remote Application of the DRBEM for numerical solution of Cattaneo-Vernotte bioheat transfer equation
Majchrzak E., Kałuża G., Poteralska J.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2008
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Vol. 7, nr 1
111-120
EN
The 1D problem of heat transfer in the tissue subjected to action of external heat source is considered. This phenomenon is described by Cattaneo-Vernotte equation supplemented by adequate boundary and initial conditions. To solve the problem formulated the dual reciprocity boundary element method (DRBEM) is applied. In the final part of the paper the examples of computations are shown.
17
Content available remote Numerical solution of bioheat transfer equation by means of the dual reciprocity BEM
Drozdek J., Majchrzak E.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2007
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Vol. 6, nr 1
47-56
EN
Application of the standard boundary element method for numerical solution of the bioheat transfer equation requires discretization not only the boundary but also the interior of the domain considered. It results from the presence of internal heat sources in the biological tissue (metabolic and perfusion sources). In this paper the variant of the BEM which is connected only with the boundary discretization is presented. It is the essential advantage of the algorithm proposed in comparison with the classical one. As example, the problem of temperature field computations in heating biological tissue domain is solved.
18
Content available remote 3D thermal wave model of bioheat transfer : solution by means of finite difference method
Kałuża G., Majchrzak E.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2007
|
Vol. 6, nr 1
91-98
EN
Up to the present, the models describing temperature distribution in the biological tissue as a rule based on the Pennes bioheat transfer equation. Taking into account the nonhomogeneous inner structure of tissue the heat conduction proceeding in this domain should be described by the hyperbolic equation. In the paper the algorithm of numerical solution of hyperbolic heat conduction equation is presented. The explicit variant of finite differences method is applied and the results of computations are shown.
19
Modelling of heating tissue process with interval thermal parameters
Piasecka-Belkhayat A.
Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska
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2006
|
z. 26
285-290
EN
In the paper the numerical analysis of heat transfer process proceeding in the domain of a biological tissue is presented. In particular, the one-dimensional problem is considered, in which the thermophysical parameters (volumetric specific heat and heat conduction) are given as intervals. The problem discussed has been solved using the 1st scheme of the interval boundary element method. The interval Gauss elimination method with the decomposition procedure has been applied to solve the obtained interval system of equations. In the final part of the paper the results obtained are shown.
20
Content available remote Identification of latent heat of biological tissue subjected to the freezing
Majchrzak E., Dziewoński M., Kałuża G.
Prace Naukowe Instytutu Matematyki i Informatyki Politechniki Częstochowskiej
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2006
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Vol. 5, nr 1
106-113
EN
In the paper the inverse problem consisting in the identification of volumetric latent heat of tissue subjected to the freezing is presented. Three different hypotheses concerning the substitute thermal capacity associated with the latent heat evolution are discussed. The 1D problem is considered and on the basis of the cooling curve on the skin surface the volumetric latent heat is estimated. In order to solve the inverse problem the least squares method containing the sensitivity coefficients is applied. In the final part of the paper the results of computations are shown.
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