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Journal of Environmental Protection 2011年第5期2卷 662-667页

作者： Manda Karunakar Reddy Mareddy sumathi Scientist NEERI Zonal Laboratory Hyderabad

The aerodynamic diameter of an air borne particle is the key property in determining its respiratory deposition. The study aim to assess PM2.5 level and its size distribution at 5 traffic junctions located along the lateral highway connected to NH-202. A cascade impactor has been used to measure the size function range of PM2.5 apart from PM10 of atmospheric dust particles in air being PM2.5 is concern with respect to effect on human health and is able to tend deeply into the respiratory tract reaching the lungs. It is observed that weight % of PM2.5 values are in the range of 40% - 60% of PM10 and few values of PM2.5 are exceeding the standards prescribed by CPCB. It is concluded that free flow of traffic is main concern and maintenance of road should be carried out during low traffic hours.

关键词： PM2.5 Air Borne Particle Traffic Respirable Dust Particle Size

THD Analysis of Cascaded H-Bridge Inverter with Fuzzy Logic Controller

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Circuits and Systems 2017年第7期8卷 171-183页

作者： Sivakumar N. sumathi A. Department of EEE Jayalakshmi Institute of Technology Thoppur India Department of ECE Adhiyamaan College of Engineering Hosur India

In recent days, the multilevel inverter technology is widely applied to domestic and industrial applications for medium voltage conversion. But, the power quality issues of the multilevel inverter limit the usage of much sensitive equipment like medical instruments. The lower distortion level of the output voltage and current can generate a quality sinusoidal output voltage in inverters and they can be used for many applications. The harmonics can cause major problems in equipments due to the nonlinear loads connected with the power system. So, it is necessary to minimize the losses to raise its overall efficiency. In this paper, a new topology of seven level asymmetrical cascaded H-bridge multilevel inverter with a Fuzzy logic controller had been implemented to reduce the Total Harmonic Distortion (THD) and to improve the overall performance of the inverter. The proposed model is well suited for use with a solar PV application. In this topology, only six IGBT switches are used with three different voltage ratings of PV modules (1:2:4). The lower number of semiconductor switches leads to minimizing overall di/dt ratings and voltage stress on each switches and switching losses. The gate pulses generated by Sinusoidal Pulse Width Modulation (SPWM) technique with a Fuzzy logic controller are also introduced. A buck-boost converter is used to maintain the constant PV voltage level integrated by an MPPT technique followed by Perturb and Observer algorithm is also implemented. The MPPT is used to harness the maximum power of solar radiations under its various climatic conditions. The new topology is evaluated by a Matlab/Simulink model and compared with a hardware model. The results proved that the THD achieved by this topology is 1.66% and realized that it meets the IEEE harmonic standards.

关键词： Cascaded H-Bridge Multilevel Inverter THD Photo Voltaic Modules SPWM Fuzzy Logic Controller MPPT Technique

Performance Analysis of Accelerator Architectures and Programming Models for Parareal Algorithm Solutions of Ordinary Differential Equations

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Journal of Computer and Communications 2021年第2期9卷 29-56页

作者： sumathi Lakshmiranganatha Suresh S. Muknahallipatna Department of Electrical and Computer Engineering University of Wyoming Laramie USA

Increasing needs for the study of complex dynamical systems require computing solutions of a large number of ordinary and partial differential time-dependent equations in near real-time. Numerical integration algorithms, which are computationally expensive and inherently sequential, are typically used to compute solutions of ordinary and partial differential time-dependent equations. This presents challenges to study complex dynamical systems in near real-time. This paper examines the challenges of computing solutions of ordinary differential time-dependent equations using the Parareal algorithm belonging to the class of parallel-in-time algorithms on various high-performance computing accelerator-based architectures and associated programming models. The paper presents the code refactoring steps and performance analysis of the Parareal algorithm on two accelerator computing architectures: the Intel Xeon Phi CPU and Graphics Processing Unit many-core architectures, and with OpenMP, OpenACC, and CUDA programming models. The speedup and scaling performance analysis are used to demonstrate the suitability of the Parareal to compute the solutions of a single ordinary differential time-dependent equation and a family of interdependent ordinary differential time-dependent. The speedup, weak and strong scaling results demonstrate the suitability of Graphical Processing Units with the CUDA programming model as the most efficient accelerator for computing solutions of ordinary differential time-dependent equations using parallel-in-time algorithms. Considering the time and effort required to refactor the code for execution on the accelerator architectures, the Graphical Processing Units with the OpenACC programming model is the most efficient accelerator for computing solutions of ordinary differential time-dependent equations using parallel-in-time algorithms.

关键词： Accelerators Many-Core Directive-Based Time-Parallel Scaling Speedup

Reliability Analysis of a Redundant Cascade System by Using Markovian Approach

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Journal of Applied Mathematics and Physics 2015年第7期3卷 911-920页

作者： Nalabolu Swathi Tallapureddy sumathi Uma Maheswari Department of Mathematics Kakatiya University Warangal India

In the present work, it is assumed that the n-components are arranged in the hierarchial order. The n-cascade system surviving with loss of m components by k number of attacks is studied;the general equation for the reliability is obtained for the above said system;and the system reliability is computed numerically for 6-cascade system for 2-number of attacks.

关键词： Cascade System Redundancy Reliability Markov Process k Attacks

Ethane dimethylsulphonate selectively destroys Leydig cells in the adult bonnet monkeys (Macaca radiata)

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Asian Journal of Andrology 1999年第3期1卷 115-120页

作者： R.sumathi V.Sriraman B.S.Kurkalli F.F.G.Rommerts A.JagannadhaRao Department of Biochemistry Development and Genetics Indian Institute of ScienceBangalore 560012India Department of Biochemistry Erasmus University RotterdamRotterdam 3000 DRThe Netherlands 不详

Aim:To study the effect of intratesticular administration of ethane-1,2-dimethylsulphonate(EDS)which has been exten-sively used to selectively destroy Leydig cells in rats and study the role of gonadotropin in regulation of differentiation ofLeydig cells(LC)in the adult male bonnet *** and Results:In vitro studies with cultured interstitialcells isolated from monkey testis revealed an inhibitory effect of EDS on LC as assessed by decrease in testosterone *** administration of EDS(5,10,20,50 mg/testis)resulted in a dose-dependent rapid decrease inserum testosterone levels,with a 65%decrease with 5 mg of EDS by the 3rd day,which returned to control levels by the45th *** treatment resulted in a significant decrease in testicular *** addition a significant decrease in[(125)~I]hCG binding and phenylesterase activity in the interstitial cells was *** analysis of the testes onthe 5th day after administration of EDS revealed an interstitium devoid of LC indicating the destructive action of ***:The monkey LC are sensitive to destructive action of EDS.

关键词： Macaca radiata ethane dimethylsulphonate Leydig cells testosterone

Graphical Processing Unit Based Time-Parallel Numerical Method for Ordinary Differential Equations

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Journal of Computer and Communications 2020年第2期8卷 39-63页

作者： sumathi Lakshmiranganatha Suresh S. Muknahallipatna Department of Electrical and Computer Engineering University of Wyoming Laramie WY USA

On-line transient stability analysis of a power grid is crucial in determining whether the power grid will traverse to a steady state stable operating point after a disturbance. The transient stability analysis involves computing the solutions of the algebraic equations modeling the grid network and the ordinary differential equations modeling the dynamics of the electrical components like synchronous generators, exciters, governors, etc., of the grid in near real-time. In this research, we investigate the use of time-parallel approach in particular the Parareal algorithm implementation on Graphical Processing Unit using Compute Unified Device Architecture to compute solutions of ordinary differential equations. The numerical solution accuracy and computation time of the Parareal algorithm executing on the GPU are demonstrated on the single machine infinite bus test system. Two types of dynamic model of the single synchronous generator namely the classical and detailed models are studied. The numerical solutions of the ordinary differential equations computed by the Parareal algorithm are compared to that computed using the modified Euler’s method demonstrating the accuracy of the Parareal algorithm executing on GPU. Simulations are performed with varying numerical integration time steps, and the suitability of Parareal algorithm in computing near real-time solutions of ordinary different equations is presented. A speedup of 25× and 31× is achieved with the Parareal algorithm for classical and detailed dynamic models of the synchronous generator respectively compared to the sequential modified Euler’s method. The weak scaling efficiency of the Parareal algorithm when required to solve a large number of ordinary differential equations at each time step due to the increase in sequential computations and associated memory transfer latency between the CPU and GPU is discussed.

关键词： Time-Parallel Differential Equation Numerical Integration Graphic Processing Unit

Detection of Link Fault Using Risk Modelling and Improving QOS Parameters in IP/WDM Networks

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Circuits and Systems 2016年第9期7卷 2217-2233页

作者： K. Sashi Rekha M. sumathi Department of Information Technology R. M. K. Engineering College Thiruvallur India Department of Electronics and Communication Engineering Dhirajlal Gandhi College of Technology Salem India

An operational backbone network is connected with many routers and other devices. Identifying faults in the network is very difficult, so a fault localization mechanism is necessary to identify fault and alleviate it and correct the faults in order to reduce the network performance degradation. A risk model needs to be devised based on the dynamic database by creating alternate path and the network is reconfigured by identifying dynamic paths. In this paper, an on-demand link state routing approach is used for handling failures in IP backbone networks and a localization algorithm is used to improve QOS parameters based on threshold value of gateway. It is proved that on-demand link state routing guarantees loop-free forwarding to reachable destinations regardless of the number of failures in the network, and in case of localization algorithm using modification process packet loss is avoided based on threshold value of gateway. Heuristic algorithm is also used for reconfiguration of dynamic path for effective fault localization. In this paper, in order to change the traffic condition, reconfiguration strategic is dynamically used. Dijikstra’s shortest path algorithm has been used to determine the shortest path between node pairs. Using risk modeling mechanism, a small set of candidate faults is identified. The concept of Fault Localization is used to minimize the fault occurring in the node and sends original path to node pairs. The localization algorithm based on MODIFICATION PROCESS, packet loss is avoided in the network by checking threshold value of gateway. If the threshold value is maximum, router directly forwards the packet to destination through gateway and if the threshold value is minimum, router compresses the packet and forwards the packet to destination with notification via gateway.

关键词： Virtual Topology Reconfiguration Load Balancing Localization Algorithm On-Demand Link State Routing Localization Algorithm Based Modification

High-Performance FIR Filter Implementation Using Anurupye Vedic Multiplier

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Circuits and Systems 2016年第11期7卷 3723-3733页

作者： S. Jayakumar Dr. A. sumathi Department of EIE Adhiyamaan College of Engineering Hosur India Department of ECE Adhiyamaan College of Engineering Hosur India

In this, today’s world immeasurable analysis goes within the field of communication and signal processing applications. The FIR filter is mostly employed in filtering applications to enhance the quality of the signal. In any processor, the performance of the system is based on the speed of the multiplier unit involved in its operation. Since multiplier forms the indispensable building blocks of the FIR filter system. Its performance has contributed in determining the execution of the FIR filter system. Also, due to the tremendous development in the technology, many approaches such as an array, Vedic methods are made to speed up the multiplier computations. The problem in speed-up operation and resource utilization of hardware with all the conventional methods due to the critical path found in partial products has to be optimized using proposed method. This paper presents the implementation and execution of a FIR Filter design using Anurupye multiplier. Here the FIR filter is examined by using various multiplier algorithms such as Anurupye, Urdhava Tiryagbhyam, and array multipliers. The FIR filter is simulated for analyzing delay;area and power are meted out and lessened by utilizing proposed Anurupye multiplier. The FIR filter design utilizing proposed multiplier offers delay around 18.99 and only 4% of LUT slice utilization compared to existing methods. This architecture is coded in VHDL, simulated using the ModelSim and synthesized with Xilinx.

关键词： Finite Impulse Response (FIR) Filter Urdhava Triyagbhyam Anurupye Vedic Multiplier Very High-Speed Hardware Description Language (VHDL)

Oscillatory and Asymptotic Behaviour of Solutions of Two Nonlinear Dimensional Difference Systems

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Journal of Applied Mathematics and Physics 2019年第4期7卷 1001-1011页

作者： G. Saraswathi P. sumathi Department of Mathematics Chellammal Women’s College Chennai India Department of Mathematics C. Kandaswami Naidu College for Men Chennai India

This paper deals with the some oscillation criteria for the two dimensional difference system of the form: . Examples illustrating the results are inserted.

关键词： Asymptotic Two-Dimensional Difference Systems

印度南部2型糖尿病患者糖尿病视网膜病变相关危险因素的研究（英文）

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国际眼科杂志 2017年第9期17卷 1615-1619页

作者： Senthilvel Vasudevan sumathi Senthilvel Jayanthi Sureshbabu 甘露医学科学研究院生物统计系印度喀拉拉邦682041 甘露护理学院基础护理与助产系印度喀拉拉邦682041 印度医学科学研究所印度本地治里605004

目的:探究2型糖尿病患者糖尿病视网膜病变(DR)的严重度及受试者中糖尿病视网膜病变严重程度与其病程、糖化血红蛋白水平、高血压史、年龄和性别的相关性。方法:横断面研究。2012-05/06,采取简单随机抽样方法进行结构化问卷调查,收集100... 详细信息

目的:探究2型糖尿病患者糖尿病视网膜病变(DR)的严重度及受试者中糖尿病视网膜病变严重程度与其病程、糖化血红蛋白水平、高血压史、年龄和性别的相关性。方法:横断面研究。2012-05/06,采取简单随机抽样方法进行结构化问卷调查,收集100例年龄≥35岁糖尿病视网膜病变患者。进行描述性统计、单变量和多变量有序逻辑回归分析。用excel表进行数据录入,并用SPSS 21.0进行数据分析(P<0.05)。结果:100例患者,平均年龄53.16±10.81(35~78)岁。通过单因素分析发现,糖尿病视网膜病变严重度与年龄(P<0.01),糖尿病病程(P<0.001),糖化血红蛋白水平(P<0.001),糖尿病家族史(P<0.01),高血压病史(P<0.05),均呈正相关,高密度脂蛋白(HDL)及年龄与DR严重程度无相关性。除年龄因素外,上述所有因素均为影响糖尿病视网膜病变严重度的独立风险因素。结论:研究表明,糖尿病病程、糖化血红蛋白水平、糖尿病家族史、高血压病史以及性别与糖尿病视网膜病变严重程度密切相关。但多因素分析中,年龄、HDL因素与DR严重程度无关。因此,利用现有治疗手段的有效性和及时控制,可以预防和消除视力威胁性疾病,延缓DR的发生。

关键词：糖尿病视网膜病变风险因素糖尿病视网膜病变严重度多变量分析