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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

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

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

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

Design of a 2-DOF-PID controller using an improved sine-cosine algorithm for load frequency control of a three-area system with nonlinearities

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Protection and Control of Modern Power Systems 2022年第1期7卷 490-507页

作者： Neelesh kumar Gupta Manoj kumar Kar arun kumar Singh Department of Electrical Engineering NIT JamshedpurJamshedpurJharkhand 831014India

This paper proposes an improved sine-cosine algorithm(ISCA)based 2-DOF-PID controller for load frequency control.A three-area test system is built for study,while some physical constraints(nonlinearities)are considered for the investigation of a realistic power *** proposed method is used as the parameter optimizer of the LFC control-ler in different *** 2-DOF-PID controllers are used because of their capability of fast disturbance rejection without significant increase of overshoot in set-point *** 2-DOF-PID controllers’efficacy is observed by examining the responses with the outcomes obtained with PID and FOPID *** simulation results with the suggested scheme are correlated with some of the existing algorithms,such as SCA,SSA,ALO,and PSO in three dif-ferent scenarios,i.e.,a disturbance in two areas,in three areas,and in the presence of physical *** addition,the study is extended to a four-area power *** analysis is performed using the Wilcoxon Sign Rank Test(WSRT)on 20 independent *** confirms the supremacy of the proposed method.

关键词： 2-DOF-PID FOPID Load frequency control WSRT Statistical analysis Improved sine-cosine algorithm

Underground mining of thick coal seams

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International Journal of Mining Science and Technology 2015年第6期25卷 885-896页

作者： kumar Rakesh Singh arun kumar Mishra Arvind kumar Singh Rajendra Central Institute of Mining and Fuel Research (CIMFR under CSIR) Indian School of Mines (ISM)

This paper reviews underground mining methods for total thickness of a thick coal seam in single lift （TI＇rCSSL）. Review shows the required engineering for extraction of thick seams needs to be fitted with thickness of the seam, behavior of rock-mass and surrounding stress conditions for efficient mining. Variants of TI＇rCSSL are able to extract a maximum 10-12 m thickness only. An improvement in bending moment of the overlying coal band in longwall top coal caving （LTCC） provides better under-winning opportunity for the roof coal band. An acceptable limit of 25 MPa compressive strength of coal for the success of LTCC may be increased under favorable geo-technical conditions. Bord and pillar in India adopted induced caving of roof coal band for single lift depillaring of total thickness （SLDTr） of a compe- tent thick coal seam developed along floor. Case studies are given to arrest the adverse effects of extrac- tion height on pillars.

关键词： Thick coal seamSingle lift depillaring of total thicknessCSmIT)Extraction heightPillar instabilityCaving of coal

Channel estimation and channel tracking for correlated block-fading channels in massive MIMO systems

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Digital Communications and Networks 2018年第2期4卷 138-147页

作者： Suresh Dahiya arun kumar Singh Department of Electrical Engineering Indian Institute of Technology Jodhpur Rajasthan 342011 India

This paper presents a channel estimation and tracking method for correlated block-fading channels in massive MIMO wireless cellular systems. In order to conserve resources, the proposed algorithm requires the uplink pilot signal only once, at the start of communication. By utilizing the temporal correlation between consecutive Resource Blocks （RBs） and the error correction capability of turbo codes, the channel matrix in subsequent RBs is estimated at the Base Station （BS） itself using the uplink data of current the RB and the estimated channel matrix of previous the RB. Compared to existing blind estimation methods, the proposed method places fewer limitations on the system settings such as the number of BS antennas, the number of users, and the number of coherent channel usage compared to existing blind estimation methods. Simulation results show that the proposed algorithm provides better performance for a moderate RB size, a high-order of QAM scheme, and a smaller ratio of the number of BS antennas and mobile terminals （N/K）. For a reasonably small N/K （order of 10）, the proposed scheme achieves a lower symbol error probability than the conventional pilot-based estimation approach.

关键词： Massive MIMO Channel estimation Resource block Turbo coding Mobile terminal

Do parental coronary heart disease risk factors(non-modifiable) effect their young ones?

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Asian Pacific Journal of Tropical Biomedicine 2015年第2期5卷 113-123页

作者： arun kumar Department of Biochemistry Manipal College of Medical Sciences Kathmandu University

Objective:To study the differences between the lipid profiles of the subjects whose parents are having known non-modifiable risk factors such as obesity,hypertension(HTN),myocardial infarction and diabetes,and compare them with the lipid profiles of the subjects whose parents are not having those risk ***:A total of 402 subjects were recruited to this study.A detailed questionnaire which included information on the past medical history,height,weight,blood pressure,physical activity,smoke,alcohol,family history of coronary heart disease,*** and *** demographic data and dietary habits were completed by all *** samples were obtained from all subjects after 14 *** profiles were analyzed using automated *** results were analyzed using SPSS software ***:The mean body mass index of the population was well below the cut-off value of obesity(>24.5 kg/m") and high risk of future cardiovascular disorder(CVD) events in this age *** mean levels of total cholesterol(TC),triglycerides(TG) and TC/high density lipoprotein(HDL) were less than the risk levels indicative of future CVD events according to the ATP Ⅲ cut-off *** the mean HDL level in our population was slightly greater than the cut-off value while the mean low density lipoprotein level was almost similar to the risk *** were observed when the subjects without history of maternal obesity were compared with subjects with history of maternal *** greater percentage of subjects who are having risk levels of body mass *** density *** TC/*** that maternal obesity contributed to the greater susceptibility of developing CVD risk in their ***:Advancing age may result in changes that could be atherogenic in the *** atherogenic changes have already initialed when the subjects are about 21 years *** incidence of atherogenic changes is far greater when mothers wh

关键词： Non-modifiable cardiovascular risk factors Lipid profile Obesity Nepalese Basal metabolic index Athcrogcnesis