Сринивасан Сабаратинам
Факультет компьютерных наук
Должности
- Доцент — Факультет компьютерных наук, Департамент анализа данных и искусственного интеллекта
- Старший научный сотрудник — Факультет компьютерных наук, Научно-учебная лаборатория моделирования и управления сложными системами
Био
- · Начал работать в НИУ ВШЭ в 2021 году.
Образование
- 2016 · PhD
- 2010 · Магистратура: Университет Бхаратидасан, специальность «Физика», квалификация «Магистр наук»
Опыт работы
- · 2021-2024: : Постдок: Лаборатория моделирования и управления сложными системами, Национальный исследовательский университет (ВШЭ), Москва, Россия. Личная страница
- · 2019-2021: : Постдок: Группа BSICoS, I3A, Арагонский институт инженерных исследований, Университет Сарагосы, Испания
- · 2017-2019: : Постдок/руководитель проекта: Кафедра физики и астрофизики, Делийский университет, Нью-Дели, Индия
- · 2017-2018: : Технический ассистент и преподаватель: Преподавание программирования на языке 'C' для магистрантов в компьютерной лаборатории, кафедра физики и астрофизики, Делийский университет, Нью-Дели -110007. Эта возможность была предоставлена в рамках программы NPDF
- · 2016-2017: : Доцент кафедры физики: Преподавал инженерную физику и материаловедение на факультете науки и гуманитарных наук, Академия высшего образования Карпагам, Университет Карпагам, г. Коимбатур, Тамилнад, Индия (18.01.2017 - 30.04.2017)
- · 2013-2016: : Технический ассистент и преподаватель: Поддержка магистрантов в Школе физики, Университет Бхаратхидасан, в рамках программы UGC-BSR. Исследовательская стипендия в области науки для выдающихся студентов в форме старшего научного сотрудника/младшего научного сотрудника (29.03.2013 - 28.11.2016)
Идентификаторы исследователя
- ORCID:
0000-0003-2445-4800 - ResearcherID:
AAY-1493-2020 - Google Scholar: https://scholar.google.com/citations?user=ANWFuZIAAAAJ&hl=en
Публикации (27)
Dynamics analysis and fractional-order nonlinearity system via memristor-based Chua oscillator
2023 · ARTICLE · en
This article discusses the utilisation of a Chua oscillator with a memristor to produce chaos with minimal nonlinearity. The memristor, a device that changes its flux or charges over time, has its nonlinear strength altered fractionally to determine the lowest-order memristor nonlinearity for generating chaos. An experimental analog circuit in real-time has been constructed. A linear parameter varying (LPV) approach, incorporating a suitable Lyapunov functional (LK) method, has been introduced to find new sufficient conditions for the robust stability of the resulting closed-loop system through linear matrix inequalities (LMIs). By observing the behaviour of the system without control, it is possible to understand the basic characteristics of chaotic oscillations and how they are affected by changes in the fractional order. These results can then be used as a starting point to study the effectiveness of various control techniques, such as feedback control, in reducing chaos and stabilising the system of this article. The efficiency of the cost-function-based control scheme is evaluated using the simulation results and relevant applications are addressed.
Artificial Intelligence and Mathematical Models of Power Grids Driven by Renewable Energy Sources: A Survey
2023 · ARTICLE · en
To face the impact of climate change in all dimensions of our society in the near future, the European Union (EU) has established an ambitious target. Until 2050, the share of renewable power shall increase up to 75% of all power injected into nowadays’ power grids. While being clean and having become significantly cheaper, renewable energy sources (RES) still present an important disadvantage compared to conventional sources. They show strong fluctuations, which introduce significant uncertainties when predicting the global power outcome and confound the causes and mechanisms underlying the phenomena in the grid, such as blackouts, extreme events, and amplitude death. To properly understand the nature of these fluctuations and model them is one of the key challenges in future energy research worldwide. This review collects some of the most important and recent approaches to model and assess the behavior of power grids driven by renewable energy sources. The goal of this survey is to draw a map to facilitate the different stakeholders and power grid researchers to navigate through some of the most recent advances in this field. We present some of the main research questions underlying power grid functioning and monitoring, as well as the main modeling approaches. These models can be classified as AI- or mathematically inspired models and include dynamical systems, Bayesian inference, stochastic differential equations, machine learning methods, deep learning, reinforcement learning, and reservoir computing. The content is aimed at the broad audience potentially interested in this topic, including academic researchers, engineers, public policy, and decision-makers. Additionally, we also provide an overview of the main repositories and open sources of power grid data and related data sets, including wind speed measurements and other geophysical data.
Fuzzy Sampled-Data Stabilization of Hidden Oscillations in a Memristor-Based Dynamical System
2023 · ARTICLE · en
In the manuscript, we report the dynamics of the Takagi–Sugeno (T–S) fuzzy memristor-based hidden system via sampled-data control. For an open-loop formulation, the system dynamics are studied. We found extreme events, hidden attractors, and trivial period doubling scenarios and confirmed them through numerical, analytical, statistical and experimental analyses. Furthermore, to enable stability analysis and control combination, the (T–S) fuzzy algorithm is employed to control the dynamics of a nonlinear system. First, we designed the sampled data fuzzy controller (SDFC) for the proposed system. Second, the Lyapunov–Krasovskii functional (LKF) strategy, novel integral inequality mechanisms, and certain sufficient conditions are determined by deriving the linear matrix inequalities (LMIs), which ensure the asymptotic stability of the system. Moreover, the sampled data control gains are computed for the large sampling interval, and numerically obtained results confirm the theoretical results. Additionally, a simple real-time analog electronic circuit is constructed, and experimental data is obtained, and finally, numerically simulated results were verified through MATLAB.
Super-extreme events in a forced Bonhoeffer–van der Pol oscillator
2023 · ARTICLE · en
Super-extreme events (SEEs) are considered rare events and have been reported by only a few researchers. However, interest in these occurrences have increased nowadays because of their possible applications in analysing different systems, such as biological, chemical, electrical and engineering systems. In this paper, we report the phenomenon of SEEs in the forced Bonhoeffer–van der Pol (BVP) oscillator-a two-dimensional forced system. We investigate the general dynamics of this system through time series analysis, two-dimensional phase diagrams, surface-of-section plots, one-parameter bifurcation diagrams, Lyapunov spectra and verify the existence of SEEs using characterisation tools, such as phase slips studies and probability distributions analysis. The novelty of our work lies in the fact that we report the observation of extreme and super-extreme events in real-time by simple low-dimensional nonlinear circuit.
Emergence of extreme events in coupled systems with time-dependent interactions
2022 · ARTICLE · en
We present a class of extreme events manifested in dynamical systems involving time-dependentattractive and repulsive couplings. We consider two cases of time-varying coupling strengths -(i) explicit time-dependence (periodically varying) and (ii) implicit time dependence (distance-dependent coupling). In both of these cases, the coupled systems generate quasi-stable equilibriumpoints, which in turn are responsible for the generation of extreme events. In the explicit time-dependent case, the quasi-stable equilibrium points are periodically created whenever the amplitudeof the external force is higher than the threshold value. In the implicit time-dependent case, theyexist whenever the distance between the trajectories is below a critical distance. We demonstrate theresults with the examples of two, three, and a network of hundred coupled Stuart-Landau oscillators.We also show the prevalence of this phenomenon in other dynamical systems (van der Pol oscillator)and highlight its applications in natural systems.
Dynamical Analysis of T–S Fuzzy Financial Systems: A Sampled-Data Control Approach
2022 · ARTICLE · en
This paper investigates the sampled-data stabilization of the Takagi–Sugano (T–S) fuzzy system, focusing on the existence of extreme event (EE) and its application to the financial model. The mathematical model of finance system is constructed through real time hardware experiment for the first time. The EE is identified in certain ranges of system parameters, is characterized and confirmed through numerical, analytical and experimental investigations. The stability analysis confirms that the EE occurs via an interior crisis phenomenon. The dynamical system is identified through bifurcation analysis and its corresponding Lyapunov exponent. The second phase of the manuscript is that, by building an appropriate Lyapunov function, sufficient conditions are derived to guarantee that the addressed T–S fuzzy financial system is asymptotically stable. The proposed stability conditions are expressed in terms of linear matrix inequalities (LMIs). In addition, the sampled-data control techniques are used to stabilize the EE. Finally, the simulation result is presented to support the proposed control scheme.
Estimation of potassium levels in hemodialysis patients by T wave nonlinear dynamics and morphology markers
2022 · ARTICLE · en
Objective: Noninvasive screening of hypo- and hyperkalemia can prevent fatal arrhythmia in end-stage renal disease (ESRD) patients, but current methods for monitoring of serum potassium ([K+]) have important limita-tions. We investigated changes in nonlinear dynamics and morphology of the T wave in the electrocardiogram (ECG) of ESRD patients during hemodialysis (HD), assessing their relationship with [K+]and designing a [K+]estimator.
Fabrication and characterizations of electro-mechanical actuators based on fullerene-reinforced biocompatible polymer
2022 · ARTICLE · en
Fullerenes have been extensively investigated in biomedical and material science, owing to their distinct physic- chemical properties. At this juncture, we validated the improved electro-mechanical actuation of Fullerene- reinforced sulfonated polyetherimide (SPEI) as a novel electromechanical actuator. In the specific, tiny amount of Fullerene (0.5 wt%) reinforced in the SPEI matrix, the bending distortion of the Fullerene-SPEI ac- tuators is tripled. As-prepared actuators showed excellent proton conductivity, substantial mechanical strength, high dielectric constant and blocking force, and exhibited large bending motion under harmonic and step re- sponses. Moreover, the biocompatibility of Fullerenes and SPEI makes these actuators as auspicious candidates in biomedical devices, robotics, and smart textiles
New results on T–S fuzzy sampled-data stabilization for switched chaotic systems with its applications
2022 · ARTICLE · en
This study presents a T–S fuzzy-based sampled-data controller for switched chaotic systems. First, we designed the switched-based sampled-data fuzzy controller. Second, a novel time-dependent Lyapunov–Krasovskii functional (LKF) approach with the information of switching signals is proposed, which covers all information of the sampling interval and the time-delay information in the controller, improving the integral inequality, some sufficient conditions are established, which makes the proposed closed-loop system be exponentially stable. Subsequently, the derived conditions are formulated with respect to linear matrix inequalities (LMIs). Meanwhile, the corresponding sampled-data controller gains are designed under the larger sampling interval. Finally, the suggested T–S fuzzy sampled-data controller (TSFSD) is used to demonstrate the usefulness of the approaches in the Lorenz system, Chen system, and Lu system.
Dynamical Analysis and Sampled-Data Stabilization of Memristor-Based Chua’s Circuits
2021 · ARTICLE · en
In this paper, we investigate sampled-data stabilization of memristor nonlinearity in Chua's circuits. The system stability pertaining to its switching nonlinearity covers two situations of flux thresholds. Through the stability analysis, the multistability characteristic is proved by its periodic invariant stable line. Moreover, the dynamical features of the considered system are examined in details by numerical and corresponding simulated experiments. Several statistical and analytical characteristic methods are used to confirm the existence of chaotic attractors. With the help of Lyapunov stability theory, new sufficient conditions are formulated using the linear matrix inequality (LMI) method to ensure robust stability and stabilization of closed-loop systems. Finally, we present a numerical example to ascertain the validity of the theoretical results obtained.
Курсы (1)
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Modern Concepts of Dynamical Neural Networks · 2 раза
2025/2026, 2024/2025 · Магистратура / Магистратура направление: 01.04.02 Прикладная математика и информатика / Маго-лего · Анг