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MATHEMATICAL DESCRIPTION OF GROWTH OF MULTIPLE ROOT BRANCHING STRUCTURE IN A PLANT

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International Journal of Biomathematics 2013年第3期6卷 1-10页

作者： arun kumar Department of Mathematics Government College Kota (Raj.) India

An existing growth model of Edelstien is extended and modified for multiple root branching structure or root hairs of any plant. Numerical and analytical solutions for the model are developed and compared. In the derivation it is assumed that multiple root branches are attached to the root surface that acts as a continuous source of new tips. The numerical scheme is derived with anticipation of the fact that comparison with experimental data may necessitate a more complicated model.

关键词： Uptake parameter asymptotic matching van Genuchten formula relativewater content.

Fractionally Delayed Kalman Filter

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IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 169-177页

作者： Abhinoy kumar singh Discipline of Electrical Engineering Indian Institute of Technology Indore

The conventional Kalman filter is based on the assumption of non-delayed measurements. Several modifications appear to address this problem, but they are constrained by two crucial assumptions: 1) the delay is an integer multiple of the sampling interval, and 2) a stochastic model representing the relationship between delayed measurements and a sequence of possible non-delayed measurements is known. Practical problems often fail to satisfy these assumptions, leading to poor estimation accuracy and frequent track-failure. This paper introduces a new variant of the Kalman filter, which is free from the stochastic model requirement and addresses the problem of fractional *** proposed algorithm fixes the maximum delay(problem specific), which can be tuned by the practitioners for varying delay possibilities. A sequence of hypothetically defined intermediate instants characterizes fractional delays while maximum likelihood based delay identification could preclude the stochastic model requirement. Fractional delay realization could help in improving estimation accuracy. Moreover, precluding the need of a stochastic model could enhance the practical applicability. A comparative analysis with ordinary Kalman filter shows the high estimation accuracy of the proposed method in the presence of delay.

关键词： Gaussian likelihood Kalman filter optimal Kalman gain randomly delayed measurements

Effect of simvastatin on paraoxonase 1(PON1) activity and oxidative stress

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Asian Pacific Journal of Tropical Medicine 2010年第4期3卷 310-314页

作者： arun kumar Department of Biochemistry College of MedicineThe West Bengal University of Health SciencesKalyaniNadia Pin:741235

Objective:To investigate the effect of simvastatin treatment on lipid pr of ile and oxidative stress in hypercholesterolaemic Indian population and determine the effect of simvastatin treatment on the activity of paraoxonase（PON）.Methods:Analyzed initially before medication administration and four months later after *** and lipoprotein measurement were done by enzymatic kits,high density lipoprotein（HDL） was determined by phosphotungstic acid precipitation method and low density lipoprotein（LDL） was calculated by Friedewald’s *** peroxidation was measured by three markers namely,conjugated diene,total peroxide,and *** diene was assayed by Buege and Aust *** peroxide was determined by FOX2 *** determination was carried out by Flemming method and total antioxidant status was determined by *** activity was determined by measuring the absorbance inrease of p-nitrophenol at 405 *** activity was calculated from the molar coefficient of 1 310 M-1 cm-1.Results:Simvastatin significantly reduced total cholesterol,triglycerides,LDL,conjugated diene,total peroxide and MDA levels,where as antioxidant status was significantly ***,simvastatin significantly increased PON1 activity towards ***:The results from the current study indicate simvastatin may have important antioxidant properties via increasing PON activity.

关键词： Hypercholesterolaemia Simvastatin Oxidative stress India

Major Development Under Gaussian Filtering Since Unscented Kalman Filter

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1308-1325页

作者： Abhinoy kumar singh IEEE Department of Electrical Engineering Indian Institute of Technology Indore

Filtering is a recursive estimation of hidden states of a dynamic system from noisy *** problems appear in several branches of science and technology,ranging from target tracking to biomedical monitoring.A commonly practiced approach of filtering with nonlinear systems is Gaussian *** early Gaussian filters used a derivative-based implementation,and suffered from several drawbacks,such as the smoothness requirements of system models and poor stability.A derivative-free numerical approximation-based Gaussian filter,named the unscented Kalman filter(UKF),was introduced in the nineties,which offered several advantages over the derivativebased Gaussian *** the proposition of UKF,derivativefree Gaussian filtering has been a highly active research *** paper reviews significant developments made under Gaussian filtering since the proposition of *** review is particularly focused on three categories of developments:i)advancing the numerical approximation methods;ii)modifying the conventional Gaussian approach to further improve the filtering performance;and iii)constrained filtering to address the problem of discrete-time formulation of process *** review highlights the computational aspect of recent developments in all three *** performance of various filters are analyzed by simulating them with real-life target tracking problems.

关键词： Bayesian framework cubature rule-based filtering Gaussian filters Gaussian sum and square-root filtering nonlinear filtering quadrature rule-based filtering unscented transformation

A Parallel Interval Computation Model for Global Optimization with Automatic Load Balancing

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Journal of Computer Science & Technology 2012年第4期27卷 744-753页

作者：吴勇 arun kumar Department of International Business and Asian Studies Griffith University School of Aerospace Mechanical and Manufacturing EngineeringRMIT University

In this paper, we propose a decentralized parallel computation model for global optimization using interval analysis. The model is adaptive to any number of processors and the workload is automatically and evenly distributed among all processors by alternative message passing. The problems received by each processor are processed based on their local dominance properties, which avoids unnecessary interval evaluations. Further, the problem is treated as a whole at the beginning of computation so that no initial decomposition scheme is required. Numerical experiments indicate that the model works well and is stable with different number of parallel processors, distributes the load evenly among the processors, and provides an impressive speedup, especially when the problem is time-consuming to solve.

关键词： parallel processing automatic load balancing computation model interval analysis global optimization

A state-of-the-art review of solar passive building system for heating or cooling purpose

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Frontiers in Energy 2016年第3期10卷 347-354页

作者： arun kumar NANDA C K PANIGRAHI Birla Institute of Technology Mesra Ranchiranchi 835215 India School of Electrical Engineering Kalinga Institute of Industrial Technology Bhubaneswar 751024 India

The major portion of energy in a building is consumed by heating, ventilating, and air-conditioning （HVAC）. The traditional heating and cooling systems contribute greatly to the emission of greenhouse gases, especially carbon dioxide. Four different ways, i.e., Trombe wall, solar chimney, unglazed transpired solar facade, and solar roof, are adopted for solar heating. Similarly, two major ways, i.e., evaporative cooling and building integrated evaporative cooling are adopted for cooling of the building. Therefore, an attempt has been made in this paper to compile the developments of solar heating and cooling technologies in a building.

关键词： HVAC heating cooling solar heating carbondioxide (CO2) emissions

Determination of the particle load based on detailed suspended sediment measurements at a hydropower plant

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International Journal of Sediment Research 2019年第5期34卷 409-421页

作者： Anant kumar Rai arun kumar Alternate Hydro Energy Centre

Suspended sediment particles contained in inflows of water systems of hydropower plants(HPPs) cause hydro-abrasive erosion of the hydraulic turbines and structures leading to significant maintenance costs,efficiency reductions, and downtime. Relevant parameters such as suspended sediment concentration(SSC), particle size distribution(PSD), shape, and mineralogical composition were measured with an online multi-frequency acoustic instrument and based on manually taken samples from the end of the sand trap of the Toss HPP in the Himalayan region, India. In the laboratory, the samples were analyzed using the gravimetric method, laser diffraction, turbidity, dynamic digital image processing, scanning electron microscope, petrography analysis, energy-dispersive X-ray spectroscopy, and X-ray *** online instrument and the samples provided measurement results at a single point. To investigate vertical gradients in concentration and particle sizes, additional samples were collected 9 times at 7 relative water depths. The SSC, most particle sizes, and particle shape were found to be evenly distributed over depth except d90, i.e. the diameter which is not exceeded by 90% of the particle mass. d90 measured at 76% of the water depth was in the range of fine sand and was multiplied by 1.05 to obtain an average value representative for the entire depth. Improved methodologies to quantify both particle shape and size in an analytical model for hydro-abrasive erosion are proposed. Also, the PSD measuring performance of laser diffraction and dynamic imaging was studied and similar values of the median particle sizes were obtained from both instruments. Further, multi-frequency acoustic, turbidity and laser diffraction techniques were found suitable for SSC measurement at the test case HPP.

关键词： Suspended sediment concentration Hydro-abrasive erosion Hydropower Particle size distribution Particle shape Mineralogical composition

Analyzing hydro abrasive erosion in Kaplan turbine:A case study from India

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Journal of Hydrodynamics 2016年第5期28卷 863-872页

作者： Anant Kr.RAI arun kumar Alternate Hydro Energy Centre IIT Roorkee

Sediment flow through hydro turbine causes erosion of hydraulic components resulting in drop of turbine efficiency, parti- cularly in hydropower plants of the Himalayan region. The measurement of erosion and monitoring of sediment flow in turbine are major concerns in erosion study. Attempts have been made to study erosion mainly in Pelton and Francis turbines. In this study, a simple and effective method has been presented to measure erosion in a Kaplan turbine of a run-of-river scheme Chilla hydropower plant in foothills of Himalaya. Recent techniques were used to measure sediment parameters like concentration, size, shape and mineral content. A standard erosion model is applied to estimate the erosion in Kaplan turbine blade, runner chamber and draft tube cone. A calibration factor has been proposed to apply the erosion model for site specific conditions. It has been found that the outer trailing edges of the turbine blade and upper rtmner chamber are most erosion prone zones. Sediment analysis revealed that effective operation can reduce erosion in turbine components. The estimated erosion values from model are found to be consistent with measu- red values. Finally, suggestions for design improvements and effective operation of erosion affected hydropower plants are given.

关键词： turbine sediment erosion measurement IEC 62364 hydropower

Modeling the drain current and its equation parameters for lightly doped symmetrical double-gate MOSFETs

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Journal of Semiconductors 2015年第4期36卷 44-50页

作者： Mini Bhartia arun kumar Chatterjee Electronics and Communication Department Thapar Institute of Engineering and Technology

A 2D model for the potential distribution in silicon film is derived for a symmetrical double gate MOS- FET in weak inversion. This 2D potential distribution model is used to analytically derive an expression for the subthreshold slope and threshold voltage. A drain current model for lightly doped symmetrical DG MOSFETs is then presented by considering weak and strong inversion regions including short channel effects, series source to drain resistance and channel length modulation parameters. These derived models are compared with the simulation results of the SILVACO （Atlas） tool for different channel lengths and silicon film thicknesses. Lastly, the effect of the fixed oxide charge on the drain current model has been studied through simulation. It is observed that the obtained analytical models of syrnmetrical double gate MOSFETs are in good agreement with the simulated results for a channel length to silicon film thickness ratio greater than or equal to 2.

关键词： double gate MOSFET 2D potential distribution model drain current model