387 research outputs found
МЕТОД И СИСТЕМА ОЦЕНКИ ФИЗИОЛОГИЧЕСКИХ РЕЗЕРВОВ СПОРТСМЕНА ВО ВРЕМЯ ТРЕНИРОВОК
Introduction. An assessing of the sportsman's physiological reserve (PR) and its dynamics is important when planning and carrying out a training, forecasting sportsman's results. An importance of this problem increases in highperformance sports, and energy consumption sports. A complexity of solving of this problem is caused by the requirement of taking into account of the complex of the biomedical parameters and formation of an integral parameter. This parameter reflects functioning of various body systems which provide significant income to the sportsman’s result achievement. Objective. Development of the method and the system of PR assessing allowing complex investigation of the PR during the training process. Method and materials. For achievement of the aim the tasks were formulated and solved using methods of biomedical research and engineering, mathematical processing and analysis of the diagnostically valuable parameters. Results. The complex of the biomedical parameters reflecting sportsman’s body metabolism in condition of physical exercises is formed. They are the heart rate, the heart rate variability, the pulse frequency, the systolic and diastolic pressure, the respiratory rate, the blood saturation, and the stress index by Baevsky. It is important for PR assessing to assess parameters characterizing sportsman’s physiological reserves at the current moment and its dynamics. The circle diagram is proposed for taking into account of all mentioned parameters and its variation dynamics. The value of the integral PR parameter is an area of a polygon, which is obtained on the circle diagram using normalized values of the diagnostically significant parameters. The method of biomedical investigation of the sportsman and the method of PR assessing based on the complex of the body system parameters are developed. The scheme of assessing of sportsman's body physiological reserves before and after the training is proposed. The scheme allows to assess not only sportsman's body energy consumption during the training but also its recovery after the training. General structures of the biotechnical system and a structures of systems of picking up, registration, processing, and analysis of biomedical signals for assessing of sportsman's physiological reserves are developed. Special attention is given to the development of a wearable device for synchronous registration of the complex of biomedical parameters and algorithms of assessing of the diagnostically significant parameters of sportsman's body physiological reserves. Conclusion. The proposed method of sportsman's physiologic reserves investigation and the structure of the system with spatially distributed architecture allow sport medicine doctor and coach to assess an efficiency of sportsman's training process with respect to his potential capabilities, and efficiently control the training process.Введение. Оценка физиологического резерва (ФР) спортсмена и его динамики актуальна при планировании и проведении тренировок, прогнозировании результатов спортсмена. Актуальность данной проблемы усиливается в спорте высоких достижений, в частности в энергетически затратных видах спорта. Сложность решения этой проблемы обусловлена необходимостью учета комплекса медико-биологических показателей и формирования интегрального показателя, отражающего функционирование различных систем организма, которые обеспечивают значимый вклад в достижение результата спортсмена. Цель работы. Разработка метода и системы оценки ФР, позволяющих комплексно изучить ФР во время тренировочного процесса. Методы и материалы. Для достижения поставленной цели были сформулированы и решены задачи с использованием методов медико-биологических исследований, биомедицинской инженерии, математической обработки и анализа диагностически значимых показателей. Результаты. Сформирован комплекс медико-биологических показателей организма, отражающих метаболизм организма спортсмена в условиях физических нагрузок. Это частота сердечных сокращений, вариабельность сердечного ритма, частота пульса, систолическое и диастолическое давление, частота дыхания, сатурации крови, индекс напряженности Баевского. Для оценки ФР важно оценивать показатели, характеризующие физиологические резервы спортсмена в текущий момент времени и их динамику. Предложена круговая диаграмма для комплексного учета всех перечисленных показателей и динамики их изменения. Количественной мерой интегрального показателя ФР является площадь многогранника, полученного на круговой диаграмме по нормированным значениям диагностически значимых показателей. Разработан метод проведения медико-биологических исследований спортсмена и метод оценки ФР на основе комплекса показателей систем организма, предложена схема оценки физиологических резервов организма спортсмена до и после тренировок. Она позволяет оценить не только энергозатраты организма спортсмена во время тренировок, но и его восстановление после тренировок. Разработана обобщенная структура биотехнической системы и структуры системы съёма, регистрации, обработки и анализа биомедицинских сигналов для оценки физиологических резервов спортсмена. Особое внимание уделено разработке носимого устройства для синхронной регистрации комплекса биомедицинских сигналов и алгоритмам оценки диагностически значимых показателей физиологических резервов организма спортсмена. Заключение. Предложенный метод исследования физиологических резервов спортсмена и структура системы с пространственно-распределенной архитектурой позволяют тренеру и врачу спортивной медицины оценивать эффективность тренировочного процесса спортсмена с учетом его потенциальных возможностей, эффективно управлять тренировочным процессом
On Throughput for UAV Relay Assisted for Use in Disaster Communications
In this paper, the system performance of an energy harvesting (EH) unmanned aerial vehicle (UAV) system for use in disasters was investigated. The communication protocol was divided into two phases. In the first phase, a UAV relay (UR) harvested energy from a power beacon (PB). In the second phase, a base station (BS) transmitted the signal to the UR using non-orthogonal multiple access (NOMA); then, the UR used its harvested energy from the first phase to transfer the signal to two sensor clusters, i.e., low-priority and high-priority clusters, via the decode-and-forward (DF) technique. A closed-form expression for the throughput of the cluster heads of these clusters was derived to analyze the system performance. Monte Carlo simulations were employed to verify our approach
On initial value and terminal value problems for subdiffusive stochastic Rayleigh-Stokes equation
In this paper, we study two stochastic problems for time-fractional RayleighStokes equation including the initial value problem and the terminal value problem. Here, two problems are perturbed by Wiener process, the fractional derivative are
taken in the sense of Riemann-Liouville, the source function and the time-spatial noise are nonlinear and satisfy the globally Lipschitz conditions. We attempt to give some existence results and regularity properties for the mild solution of each problem
On stochastic nonclassical diffusion equation with standard and fractional Brownian motion
This paper is concerned with the mathematical analysis of terminal value problems for a
stochastic non-classical diffusion equation, where the source is assumed to be driven by classical
and fractional Brownian motions. Our two problems are to study in the sense of well-posedness
and ill-posedness meanings. Here, a terminal value problem is a problem of determining the
statistical properties of the initial data from the final time data. In the case 0 < β ≤ 1, where
β is the fractional order of a Laplace operator, we show that these are well-posed under certain
assumptions. We state a definition of ill-posedness and obtain the ill-poseness results for the
problems when β > 1. The major analysis tools in this paper are based on properties of stochastic
integrals with respect to the fractional Brownian motion
On terminal value problems for bi-parabolic equations driven by Wiener process and fractional Brownian motions
In this paper, we study two terminal value problems (TVPs) for stochastic bi-parabolic equations perturbed by standard Brownian motion and fractional Brownian motion with Hurst parameter h ∈ ( 1/2 , 1) separately. For each problem, we
provide a representation for the mild solution and find the space where the existence of the solution is guaranteed. Additionally, we show clearly that the solution of each problem is not stable, which leads to the ill-posedness of each problem. Finally, we propose two regularization results for both considered problems by using the filter regularization method
The impact of dimethylformamide on the synthesis of graphene quantum dots derived from graphene oxide
Graphene quantum dots (GQDs) have garnered immense interest in recent years due to their unique optical, electrical, and chemical properties, making them promising candidates for various applications in optoelectronics, bioimaging, and sensing. However, enhancing the control over the size, surface chemistry, and optical properties of GQDs remains a significant challenge. In this study, a novel recipe was proposed to successfully synthesize various GQDs via a typical solvothermal process, which has proven to be a versatile and scalable approach. In addition to the main ingredient – graphene oxide suspension, dimethylformamide (DMF) and hydrogen peroxide serving as a cutting agent were added to the reaction mixture. This synthesis method was found to be more promising than the reference one in which DMF was replaced by double distilled water. Through systematic experimentation, we demonstrated that the addition of DMF enables the successful GQD production over a wider range of reaction times; hence, the UV absorption band and photoluminescence properties of GQDs can be better adjusted. The dependence of photoluminescence on the excitation wavelength was observed in the as-prepared materials as they were excited with a range of wavelengths from 360 to 480 nm. The obtained insights not only advance our understanding of GQD synthesis but also open up avenues for tailoring their properties for specific applications
Corrigendum to The impact of dimethylformamide on the synthesis of graphene quantum dots derived from graphene oxide
The original article, “Khuong T. Truong, Thach H. Pham, Khai V. Tran. The impact of dimethylformamide on the synthesis of graphene quantum dots derived from graphene oxide. Chimica Techno Acta. 2023;10(4):202310405”, is available at: https://doi.org/10.15826/chimtech.2023.10.4.0
Building a Model of Organizational Activities Experience in Natural Sciences under Stem Education Orientation
STEM educational-oriented Natural Science experience activities are learner-oriented activities Taking learners as the center in all natural science research activities applying engineering technology and mathematics STEM in solving practical problems Based on theoretical research on experiential activities STEM education and the characteristics of Natural Sciences the article studies the educational forces inside and outside the school From there it is proposed to build a model of organizational structure for experiential activities in Natural Sciences oriented toward STEM education The results of this research are meaningful in helping principals see the importance and significance of coordinating educational forces inside and outside the school in organizing experiential activities in Natural Sciences according to orientation STEM education for student
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