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<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD with OASIS Tables with MathML3 v1.4 20241031//EN" "https://jats.nlm.nih.gov/archiving/1.4/JATS-archive-oasis-article1-4-mathml3.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" dtd-version="1.4" article-type="research-article" xml:lang="en"><front><journal-meta><journal-title-group><journal-title xml:lang="ru">Математическая физика и компьютерное моделирование</journal-title></journal-title-group><issn publication-format="print">2587-6325</issn><issn publication-format="electronic">2587-6902</issn></journal-meta><article-meta><article-id pub-id-type="doi">10.15688/mpcm.jvolsu.2023.3.6</article-id><article-categories><subj-group><subject>Other</subject></subj-group></article-categories><title-group><article-title xml:lang="ru">Численное исследование влияния изменения электрической проводимости на решение прямой задачи электроимпедансной томографии</article-title><trans-title-group xml:lang="en"><trans-title>Numerical Study of the Influence of Changes in Electrical Conductivity on the Solution of the Direct Problem of Electrical Impedance Tomography</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="ru"><surname>Афанасьева</surname><given-names>Анна Александровна</given-names></name><name xml:lang="en"><surname>Afanaseva</surname><given-names>Anna A.</given-names></name></name-alternatives><xref ref-type="aff" rid="aff1"/><email>anna.afanaseva@stud.tsu.ru</email></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="ru"><surname>Старченко</surname><given-names>Александр Васильевич</given-names></name><name xml:lang="en"><surname>Starchenko</surname><given-names>Alexander V.</given-names></name></name-alternatives><xref ref-type="aff" rid="aff1"/><email>starch@math.tsu.ru</email></contrib><aff-alternatives id="aff1"><aff xml:lang="en"><institution>Tomsk State University (Tomsk, Russian Federation)</institution></aff><aff xml:lang="ru"><institution>Томский государственный университет (Томск, Российская Федерация)</institution></aff></aff-alternatives></contrib-group><pub-date pub-type="epub" iso-8601-date="2023-10-24"><day>24</day><month>10</month><year>2023</year></pub-date><volume>26</volume><issue>3</issue><fpage>76</fpage><lpage>88</lpage><history><date date-type="received" iso-8601-date="2023-06-08"><day>08</day><month>06</month><year>2023</year></date><date date-type="accepted" iso-8601-date="2023-06-28"><day>28</day><month>06</month><year>2023</year></date></history><permissions><license xlink:href="https://creativecommons.org/licenses/by-nc/4.0/" xlink:title="CC BY-NC 4.0"><ali:license_ref>https://creativecommons.org/licenses/by-nc/4.0/</ali:license_ref><license-p xml:lang="ru">CC BY-NC 4.0</license-p></license></permissions><abstract xml:lang="ru"><p>В электроимпедансной томографии (ЭИТ) определяется проводимость внутри тела с помощью электрических измерений, выполняемая на исследуемой поверхности. Сама задача ЭИТ относится к обратной задаче и является некорректной, особенно в реальных приложениях, где доступны только частичные граничные данные. ЭИТ делится на прямую и обратную задачи. Информация, полученная при решении прямой задачи, будет полезна при решении обратных задач ЭИТ, так как необходимо понимать, какие данные измерений важны, как измерять напряжение, как подавать ток, чтобы получить больше информации о внутренней структуре объекта. Чем больше будет полезной информации о распределении напряжения, тем лучше получится определить распределение проводимости в обратной задаче. В данной работе проведено численное исследование влияния изменения электрической проводимости на решение прямой задачи электроимпедансной томографии. Учитываются вариации того, как различные проводимости, конфигурации тока и сопротивления электродов влияют на напряжение.</p></abstract><abstract xml:lang="en" abstract-type="summary"><p>Electrical Impedance Tomography (EIT) uses electrical stimulation and measurement at the body surface to image the electrical properties of internal tissues. It has the advantage of non-invasiveness and high temporal resolution but suffers from poor spatial resolution and sensitivity to electrode movement and contact quality. EIT can be useful to applications where there are conductive contrasts between tissues, fluids or gases, such as imaging of cancerous or ischemic tissue or functional monitoring of breathing, blood flow, gastric motility and neural activity. The work uses a complete electrode model (CEM), which is a practical model in EIT, which most realistically models electrodes. This model can simulate EIT measurements with much greater accuracy than continuum models. The mathematical formulation of the problem is written as follows: In the article [15] shows that in order for the problem to have a unique solution, the following condition must be met: Numerical studies are consistent with the conclusions from the article [14]. Useful information in the EIT is contained mainly on a small part of the boundary, i.e., on the electrodes close to the perturbations of the electrical conductivity. Boundary measurements, which are the input to the inverse conductivity problem, are more sensitive to anomalies near the boundary and to larger anomalies. This study is useful in order to know the critical values of the parameters (size, location) of a low-amplitude perturbation of conductivity, at which the measurements are insensitive and, therefore, inhomogeneities cannot be detected.</p></abstract><kwd-group xml:lang="en"><kwd>contact impedance</kwd><kwd>elliptic equation with piecewise constant coefficients</kwd><kwd>unstructured grids</kwd><kwd>complete electrode model</kwd><kwd>conductivity</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>уравнение эллиптического типа с кусочнопостоянными коэффициентами</kwd><kwd>неструктурированные сетки</kwd><kwd>полная электродная модель</kwd><kwd>проводимость</kwd><kwd>контактное сопротивление</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена при поддержке Министерства науки и высшего образования РФ (соглашение № 075-02-2023-943).</funding-statement><funding-statement xml:lang="en">This work was supported by the Ministry of Science and Higher Education of the Russian Federation (agreement No. 075-02-2023-943).</funding-statement></funding-group></article-meta></front><back><ref-list><ref id="ref1"><mixed-citation publication-type="other" xml:lang="ru">Афанасьева, А. 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