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A New Approach of Solving Linear Fractional Programming Problem (LFP) by Using Computer Algorithm

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Open Journal of Optimization 2015年第3期4卷 74-86页

作者： Sumon Kumar Saha Md. Rezwan Hossain Md. Kutub Uddin rabindra nath Mondal Department of Applied Mathematics Gono Bishwabidyalay (University) Dhaka Bangladesh Department of Business Development Allcare Limited Dhaka Bangladesh Department of Mathematics University of Dhaka Dhaka Bangladesh Department of Mathematics Jagannath University Dhaka Bangladesh

In this paper, we study a new approach for solving linear fractional programming problem (LFP) by converting it into a single Linear Programming (LP) Problem, which can be solved by using any type of linear fractional programming technique. In the objective function of an LFP, if βis negative, the available methods are failed to solve, while our proposed method is capable of solving such problems. In the present paper, we propose a new method and develop FORTRAN programs to solve the problem. The optimal LFP solution procedure is illustrated with numerical examples and also by a computer program. We also compare our method with other available methods for solving LFP problems. Our proposed method of linear fractional programming (LFP) problem is very simple and easy to understand and apply.

关键词： Linear Programming Linear Fractional Programming Problem Computer Program

MOSFET栅氧泄漏隧穿电流的分析模型:量子力学研究(英文)

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微纳电子技术 2011年第6期48卷 357-364页

作者： Amit Chaudhry Jatindra nath roy 旁遮普大学工程与技术学院印度昌迪加尔91160014 Solar Semiconductor有限公司印度海得拉巴501359

研发了一种通过MOSFET的超薄栅氧化物分析直接隧穿电流密度的模型。采用Wentzel-Kramers-Brilliouin(WKB)近似计算了隧穿概率,利用清晰的表面势方程改进模型的准确性。在研究模型中考虑了Si衬底中反型层的量子化和多晶硅栅耗尽,还研究... 详细信息

研发了一种通过MOSFET的超薄栅氧化物分析直接隧穿电流密度的模型。采用Wentzel-Kramers-Brilliouin(WKB)近似计算了隧穿概率,利用清晰的表面势方程改进模型的准确性。在研究模型中考虑了Si衬底中反型层的量子化和多晶硅栅耗尽,还研究了多晶硅掺杂对栅氧化层隧穿电流的影响。仿真结果表明,栅氧化层隧穿电流随多晶硅栅掺杂浓度的增加而增加。该结论与已报道的结果相吻合,从而证明了该模型的正确性。

关键词：反型层量子化隧穿模型 Wentzel-Kramers-Brilliouin(WKB)近似多晶硅栅金属氧化物半导体场效应晶体管(MOSFET)

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Time-Dependent Flow with Convective Heat Transfer through a Curved Square Duct with Large Pressure Gradient

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Open Journal of Fluid Dynamics 2015年第3期5卷 238-255页

作者： rabindra nath Mondal Md. Nurul Amin Helal Poly Rani Shaha Nayan Kumar Poddar Department of Mathematics Jagannath University Dhaka Bangladesh Additional Director (Education) Training Directorate BGB Head Quarter Pilkhana Dhaka Bangladesh

A numerical study is presented for the fully developed two-dimensional laminar flow of viscous incompressible fluid through a curved square duct for the constant curvature δ = 0.1. In this paper, a spectral-based computational algorithm is employed as the principal tool for the simulations, while a Chebyshev polynomial and collocation method as secondary tools. Numerical calculations are carried out over a wide range of the pressure gradient parameter, the Dean number, 100 ≤ Dn ≤ 3000 for the Grashof number, Gr, ranging from 100 to 2000. The outer wall of the duct is treated heated while the inner wall cooled, the top and bottom walls being adiabatic. The main concern of the present study is to find out the unsteady flow behavior i.e. whether the unsteady flow is steady-state, periodic, multi-periodic or chaotic, if Dn or Gr is increased. It is found that the unsteady flow is periodic for Dn = 1000 at Gr = 100 and 500 and at Dn = 2000, Gr = 2000 but steady-state otherwise. It is also found that for large values of Dn, for example Dn = 3000, the unsteady flow undergoes in the scenario “periodic→chaotic→periodic”, if Gr is increased. Typical contours of secondary flow patterns and temperature profiles are also obtained, and it is found that the unsteady flow consists of single-, two-, three- and four-vortex solutions. The present study also shows that there is a strong interaction between the heating-induced buoyancy force and the centrifugal force in a curved square passage that stimulates fluid mixing and consequently enhance heat transfer in the fluid.

关键词： Curved Square Duct Secondary Flow Time-Evolution Periodic Solution Chaos

Development of Emission Factors for Quantification of Blasting Dust at Surface

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Journal of Environmental Protection 2010年第4期1卷 346-361页

作者： Surendra roy Govind Raj Adhikari Trilok nath Singh 不详

Environmental impact assessment (EIA) and environmental management plan (EMP) is a statutory requirement for execution of new mining projects or for expansion of the operating projects. For this purpose, quantification of blasting dust emission is required. This can be done by developing emission factors for blasting. The concept is similar to that of specific charge in blasting. For mining operations other than blasting, quantification of dust can be done using emis- sion factors. Emission estimation techniques are very limited for blasting. In this study, the emission factors were de- veloped by carrying out a detailed field study at one of the largest opencast coal mines of India in all four seasons. Da- ta on atmospheric and meteorological conditions were generated by installing sodar and automatic weather station at the mine site. Respirable dust samplers were installed for monitoring of the dust emitted during coal or overburden bench blasting. Emission factors for dust concentrations were developed in gram per cubic meter of rock excavated. The developed emission factors were used to estimate dust emissions for adjacent mines due to similarity in mining and meteorological conditions. Seasonal variations in moisture contents in benches, where dust was monitored, indicated the lowest emission factors in monsoon due to high moisture in the bench materials. Similar field studies were also conducted at another coalfield of India for two seasons. It was found that the emission factors are site-specific.

关键词： Emission Factor Blasting Dust Particulate Matter Surface Coal Mines

Human immunodeficiency virus/acquired immune deficiency syndrome: Using drug from mathematical perceptive

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World Journal of Virology 2015年第4期4卷 356-364页

作者： Amar nath Chatterjee Shubhankar Saha Priti Kumar roy Centre for Mathematical Biology and Ecology Department of Mathematics Jadavpur University

Entry of acquired immune deficiency syndrome virus into the host immune cell involves the participation of various components of host and viral cell unit. These components may be categorized as attachment of the viral surface envelope protein subunit, gp120, to the CD4+ receptor and chemokine coreceptors, CCR5 and CXCR4, present on T cell surface. The viral fusion protein, gp41, the second cleaved subunit of Env undergoes reconfiguration and the membrane fusion reaction itself. Since the CD4+ T cell population is actively involved; the ultimate outcome of human immunodeficiency virus infection is total collapse of the host immune system. Mathematical modeling of the stages in viral membrane protein-host cell receptor-coreceptor interaction and the effect of antibody vaccine on the viral entry into the susceptible host cell has been carried out using as impulsive differential equations. We have studied the effect of antibody vaccination and determined analytically the threshold value of drug dosage and dosing interval for optimum levels of infection. We have also investigated the effect of perfect adherence of drug dose on the immune cell count in extreme cases and observed that systematic drug dosage of the immune cells leads to longer and improved lives.

关键词： Human immunodeficiency virus Acquired immune deficiency syndrome Antibody vaccine Perfect drug adherence Impulsive differential equation

Saturation Effects on Immunopathogenic Mechanism of Psoriasis:A theoretical approach

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应用泛函分析学报 2011年第3期13卷 310-318页

作者： Priti Kumar roy Abhirup Datta Amar nath Chatterjee Center for Mathematical Biology and Ecology Department of MathematicsJadavpur University

Psoriasis vulgaris is a common chronic autoimmune inflammatory skin disease characterized by T-cell mediated hyper proliferation of *** type of skin disorder is characterized by macroscopic and also microscopic skin *** was observed that,psoriatic lesions are sharply demarcated,red and slightly raised lesions along with silver whitish *** striking feature of T-cell mediated chronic psoriatic lesions are the epidermal infiltration of predominantly oligoclonal CD8^+T-cells and probably also of CD4^+T-cells in the *** this research article we proposed a mathematical model for the chronic disease,psoriasis,consisting a set of differential equations, involving T-Lymphocytes cells,Dendritic cells and the epidermal Keratinocytes,incorporating half saturation constant through the T lymphocyte cells and also in that sense,it has been infiltrated in the activation process of keratinocytes in the course of the plaque of *** biological research on psoriasis has been established the suppression of epidermal T-cell *** we are interested to know how the cell biological system changes for introducing the half saturation constant in presence of suppression taking place DCs on the model *** analytical and numerical result reveal that due to control effect,the macrophages population density does not impede for the interaction between T-cell and keratinocytes.T-cell and keratinocyte population ultimately become stable after a certain period of time span.

关键词： dendritic cells helper T-cells Keratinocytes DCs dermis epidermis drug efficacy

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Effect of Angiotensin Receptor-Neprilysin Inhibitor versus Valsartan on Cardiac Status in Patients with Chronic Heart Failure with Reduced Ejection Fraction: A Randomized Clinical Trial in Rangpur Medical College Hospital, Bangladesh

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Open Journal of Internal Medicine 2020年第1期10卷 21-34页

作者： Shakil Ghafur Abu Zahid Haripada Sarkar rabindra nath Barman Abdullah Al-Mahmud Mahbubur Rahman Hasanul Islam Rangpur Medical College Hospital RangpurBangladesh

Background: Heart failure with reduced ejection fraction has a significant association with considerable morbidity and mortality, but there is still inadequacy in appropriate treatment to prevent this condition. We observed the effect of angiotensin receptor neprilysin inhibitor (ARNi) with such disorder compared to valsartan. Methods: In this single-blind trial, the patients were enrolled with chronic HF aged on or above 40 years, symptomatic NYHA class II - IV, an elevated NT-proBNP above 400 pg/ml level and a reduced LVEF of 40% or less. The patients were randomly assigned 1:1 to the treatment arms either ARNi (50 mg titrated to 100 mg twice a day) or valsartan (40 mg titrated to 80 mg twice a day) and followed for a median of 88 days. The primary outcome was mode of cardiovascular death and re-hospitalization for heart failure. Changes in the level of NT-proBNP and rate of ejection fraction were also measured. Results: Cardiovascular deaths occurred 4 (8%) in the ARNi treatment arm, while 11 (22%) in the valsartan treatment arm with significant hazard ratio in the ARNi group [Hazard Ratio = 0.37;95% CI: 0.34, 0.64;p = 0.042] during a median of 88 days of follow up period and 2 (4%) of the patients from the ARNi treatment arm were hospitalized due to HF, while in the valsartan treatment arm, 10 (20%) patients were hospitalized due to HF followed by receiving treatment respectively with hazard ratio in the ARNi group [Hazard Ratio = 0.80;95% CI: 0.57, 0.92;p Conclusion: Chronic treatment with the angiotensin receptor neprilysin inhibitor (ARNi) strongly decreases the NT-proBNP as well as morbidity and mortality and increases LVEF in patients with heart failure compared to valsartan.

关键词： Chronic Heart Failure Ejection Fraction Angiotensin Receptor-Neprilysin Inhibitor (ARNi) NT-proBNP

Insight of Viral Infection of Jatropha Curcas Plant(Future Fuel):A control based mathematical study

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应用泛函分析学报 2011年第4期13卷 366-374,412页

作者： Sumit Nandi Subhas Khajanchi Amar nath Chatterjee Priti Kumar roy Department of Chemistry Narula Institute of TechnologyKolkata-700109 Center for Mathematical Biology and Ecology Department of MathematicsJadavpur UniversityKolkata-700032 India

Jatropha Curcas Linnaeous(Jatropha Curcas L)is a wonder plant with a variety of applications and enormous economic ***,an alternative fuel from non edible vegetable oil of Jatropha Curcas plant,has the requisite potential of providing a promising and commercially viable alternative to diesel oil since it has the desirable physicochemical and performance characteristics comparable to *** alternative fuel is eco-friendly,cost effective and has the huge potentiality for the future generations throughout the *** effective cultivation of this plant, protection from different viral diseases is *** this paper,we describe the eco-epidemiological model of the plant Jatropha Curcas L for understanding the disease dynamics which helps to control the viral infection of the Jatropha Curcas plant *** this approach,this plant can grow ideally for the renewable green fuel of the future world.

关键词： Jatropha Curcas cell biodiesel asymptotic stability optimal control remedial application

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Phytochemical Screening and Evaluation of Pharmacological Potential of Baliospermum solanifolium Leaf Extract

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Clinical Complementary Medicine and Pharmacology 2024年第1期4卷 69-75页

作者： Amit Mazumder rabindra nath Acharyya Milton Kumar Kundu Pritam Kundu Md.Amirul Islam Md.Mustafizur Rahman Pharmacy Discipline Khulna UniversityKhulna-9208Bangladesh

Background:Baliospermum solanifolium is a traditional medicinal plant,locally known as“dantigaacha”from Eu-phorbiaceae family,and has been used in different diseases treatments likes helminthiasis,skin diseases,diabetes,snake-bite,and ***:Depending on the traditional uses of *** and the lack of scientific works,we aimed to conduct some pharmacological tests on its ***:Active constituents of *** were assessed by qualitative ***(2,2-diphenyl-1-picrylhydrazyl)was used for free radical scavenging *** change and mortality rate were used as indicators to assess the toxicity of *** antidiabetic potential was evaluated by oral glucose toler-ance test(OGTT)and alpha-glucosidase enzyme inhibitory *** antidiarrheal activity,castor oil-induced mice were *** test was carried out by disk diffusion assay and MIC ***,analgesic activity was done by acetic acid-induced writhing ***:*** contains alkaloids,carbohydrates,glycosides,flavonoids,tannis,phenolics *** toxicity test ensured the safety of the *** DPPH,the extract showed antioxidant activity with an IC50(con-centration needed to scavenge 50%DPPH)value of 61.65μg/*** phenolic,flavonoid and tannin contents were determined as 124 mg GAE/g,440 mg QE/g and 344 mg GAE/g dried extract,*** OGTT,the ex-tract reduced the blood glucose level *** the alpha-glucosidase inhibitory activity,the plant showed a concentration-dependent reduction of the enzyme at IC50 of 8.53 mg/*** the antidiarrheal test,*** inhibit defecation 30.69%and 53.41%at dose 250 mg/kg and 500 mg/kg,*** extract also showed antibacterial activity against four bacterial strains in the disk diffusion method and minimum inhibitory concen-tration(MIC)values were 62.5μg/mL,62.5μg/mL,125μg/mL and 62.5μg/mL against four bacterial strains,*** an

关键词： Baliospermum solanifolium Antioxidant Antidiabetic Antidiarrheal Antibacterial Analgesic