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Numerical storm surge model with higher order finite difference method of lines for the coast of Bangladesh

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Acta Oceanologica Sinica 2019年第6期38卷 100-116页

作者： Gour Chandra Paul md. Emran ali Department of Mathematics University of RajshahiRajshahi 6205Bangladesh Department of Textile Engineering Northern University BangladeshDhaka 1230Bangladesh

In this study, the method of lines (MOLs) with higher order central difference approximation method coupled with the classical fourth order Runge-Kutta (RK(4,4)) method is used in solving shallow water equations (SWEs) in Cartesian coordinates to foresee water levels associated with a storm accurately along the coast of Bangladesh. In doing so, the partial derivatives of the SWEs with respect to the space variables were discretized with 5-point central difference, as a test case, to obtain a system of ordinary differential equations with time as an independent variable for every spatial grid point, which with initial conditions were solved by the RK(4,4) method. The complex land-sea interface and bottom topographic details were incorporated closely using nested schemes. The coastal and island boundaries were rectangularized through proper stair step representation, and the storing positions of the scalar and momentum variables were specified according to the rules of structured C-grid. A stable tidal regime was made over the model domain considering the effect of the major tidal constituent, M2 along the southern open boundary of the outermost parent scheme. The Meghna River fresh water discharge was taken into account for the inner most child scheme. To take into account the dynamic interaction of tide and surge, the generated tidal regime was introduced as the initial state of the sea, and the surge was then made to come over it through computer simulation. Numerical experiments were performed with the cyclone April 1991 to simulate water levels due to tide, surge, and their interaction at different stations along the coast of Bangladesh. Our computed results were found to compare reasonable well with the limited observed data obtained from Bangladesh Inland Water Transport Authority (BIWTA) and were found to be better in comparison with the results obtained through the regular finite difference method and the 3-point central difference MOLs coupled with the RK(4,

关键词： shallow water equations method of lines higher order finite difference approximation method surge nested scheme

Selection of Rice Genotypes for Salinity Tolerance Through Morpho-Biochemical Assessment

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Rice science 2014年第5期21卷 288-298页

作者： md. Nasim ali Bhaswati GHOSH Saikat GANTAIT Somsubhra CHAKRABORTY Department of Agricultural Biotechnology Faculty Centre for Integrated Rural Development and Management School of Agriculture and Rural Development Ramakrishna Mission Vivekananda UniversityRamakrishna Mission Ashrama NarendrapurKolkata 700103 India Department of Crop Science Faculty of Agriculture University Putra Malaysia43400 Serdang SelangorMalaysia Sasya Shyamala Krishi Vigyan Kendra Ramakrishna Mission Vivekananda UniversityArapanch Sonarpur Kolkata 700150 India

The present study reported the morpho-biochemical evaluation of 15 selected rice genotypes for salt tolerance at the seedling stage. Growth parameters including shoot length, root length, plant biomass, plant turgid weight, plant dry weight along with relative water content were measured after exposure to saline solution （with electrical conductivity value of 12 dS/m）. Genotypes, showing significant differential responses towards salinity in the fields, were assessed through 14 salinity-linked morpho-biochemical attributes, measured at 14 d after exposure of seedling in saline nutrient solution. Relative water content, chlorophyll a/b, peroxidase activity and plant biomass were identified as potential indicators of salt tolerance. Principal component analysis and successive Hierarchical clustering using Euclidean distance revealed that Talmugur, Gheus, Ghunsi, Langalmura, Sabitapalui, and Sholerpona were promising genotypes for further breeding programmes in rice. The maximum Euclidean distance was plotted between Thavallakanan and Talmugur （7.49）, followed by Thavallakanan and Langalmura （6.82）, indicating these combinations may be exploited as parental lines in hybridization programmes to develop salinity tolerant variety.

关键词： chlorophyll content electrical conductivity Oryza sativa L. peroxidase activity prolinecontent relative water content salinity tolerance sugar content superoxide dismutase

Mitigation Rice Yield Scaled Methane Emission and Soil Salinity Stress with Feasible Soil Amendments

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Journal of Agricultural Chemistry and Environment 2021年第1期10卷 16-36页

作者： Laila Khatun Muhammad Aslam ali Mahmud Hossain sumon md. Bazlul Islam Fahima Khatun Department of Environmental Science Bangladesh Agricultural University Mymensingh Bangladesh Department of Soil Science Bangladesh Agricultural University Mymensingh Bangladesh Department of Seed Science and Technology Bangladesh Agricultural University Mymensingh Bangladesh Department of Pathobiology Bangabandhu Sheikh Mujibur Rahman Agricultural University Gazipur Bangladesh

Sea level rise and saline water intrusion have been affecting land use and crop production especially rice in the coastal areas of major rice growing countries including Bangladesh. The upward trend in salinity intrusion has been hampering crop production, particularly rice cultivation in the coastal areas of Bangladesh. Therefore, an experiment was conducted on rice planted saline soils under the Nethouse at Bangladesh Agricultural University, Mymensingh to improve the properties of salt affected soils for rice cultivation as well as controlling methane (CH4) emissions with feasible soil organic amendments and recommended inorganic fertilizers. The experimental treatments were arranged under 25 mM NaCl, 50 mM NaCl and 75 mM NaCl salinity levels with different combinations of NPKSZn, biochar, phosphogypsum and Trichocompost. It was found that CH4 emission rates were suppressed with phospho-gypsum and biochar amendments within the salinity level 25 mM to 50 mM, beyond this salinity level (at 75 mM), soil amendments were not effective to control CH4 emissions. From panicle initiation to grain ripening stages treatment T4 (100% NPKSZn + 75 mM NaCl stress) showed the highest CH4 emission rate, while lower CH4 emission rate was recorded in T5 (100% NPKSZn + 25 mM NaCl stress + Phospho-gypsum) and T8 treatment (100% NPKSZn + 50 mM NaCl + Phospho-gypsum). In case of s

关键词： CH4 Rice Saline Soils Phosphogypsum Biochar Trichocompost

Effects of Hydromagnetic and Thermophoresis of Unsteady Forced Convection Boundary Layer Flow over Flat Plates

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Journal of Applied Mathematics and Physics 2016年第9期4卷 1756-1776页

作者： md. Jashim Uddin md. Yeakub ali Department of Mathematics Chittagong University of Engineering & Technology Chittagong-4349 Bangladesh Department of Electrical & Electronic Engineering International Islamic University Chittagong Chittagong-4318 Bangladesh

In this paper, we analyze unsteady two dimensional hydromagnetic forced convection boundary layer flow of a viscous incompressible fluid along flat plates with thermophoresis. The potential flow velocity has been taken as a function of the distance x and time t. The governing partial differential equations are transformed to ordinary differential equation by applying local similarity transformation. The resulting similarity equations are then solved numerically for unsteady case, applying Nachtsheim-Swigert shooting iteration technique with six order Runge-Kutta method. The variations in fluid velocity, fluid temperature and species concentration are displayed graphically and discussed for different material parameters entering into the analysis. The effects of the pertinent parameters on the skin-friction coefficient, wall heat transfer coefficient and wall deposition flux rate are also displayed in tabulated form and discussed them from the physical point of view. An analysis of the obtained results shows that the flow field is influenced appreciably by the magnetic field parameter and the thermophoresis particle deposition.

关键词： Forced Convection Hydromagnetic Field Similarity Solution Unsteady Thermophoresis

Critical Properties of the Two-Dimensional Villain Model with Ferromagnetic Impurities

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World Journal of Mechanics 2017年第6期7卷 167-175页

作者： md. Yeakub ali Department of Mathematics Chittagong University of Engineering & Technology Chittagong Bangladesh

This work investigates the square lattice in the presence of an-ti-ferromagnetic exchange considering the two-dimensional Ising Villain model. A computational scheme is constructed to evaluate the degeneracy of ground states at zero temperature employing the Pfaffian method through perturbation theory. The entropy and canonical spin glass of the considered model are precisely obtained. The critical point between the Villain phase and canonical spin glass phase with the line fit of entropy at the thermodynamic limit is investigated. It is also shown that the transition point of the Villain model lies in the low concentration regime.

关键词： Villain Entropy Critical Point Square Lattice

Vector Autoregressive （VAR） Modeling and Projection of DSE

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Chinese Business Review 2015年第6期14卷 273-289页

作者： Ahammad Hossain md. Kamruzzaman md. Ayub ali Varendra University Rajshahi Bangladesh University of Rajshahi Rajshahi Bangladesh

In this paper, vector autoregressive （VAR） models have been recognized for the selected indicators of Dhaka stock exchange （DSE）. Bangladesh uses the micro economic variables, such as stock trade, invested stock capital, stock volume, current market value, and DSE general indexes which have the direct impact on DSE prices. The data were collected for the period from June 2004 to July 2013 as the basis on daily scale. But to get the maximum explorative information and reduction of volatility, the data have been transformed to the monthly scale. The outliers and extreme values of the study variables are detected through box and whisker plot. To detect the unit root property of the study variables, various unit root tests have been applied. The forecast performance of the different VAR models is compared to have the minimum residual. Moreover, the dynamics of this financial market is analyzed through Granger causality and impulse response analysis.

关键词： vector autoregressive (VAR) model impulse response analysis Granger causality

Bangla language modeling algorithm for automatic recognition of hand-sign-spelled Bangla sign language

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Frontiers of Computer Science 2020年第3期14卷 45-64页

作者： Muhammad Aminur RAHAMAN Mahmood JASIM md.Haider ali md.HASANUZZAMAN Department of Computer Science and Engineering University of DhakaDhaka-1000Bangladesh

Because of using traditional hand-sign segmentation and classification algorithm,many diversities of Bangla language including joint-letters,dependent vowels *** representing 51 Bangla written characters by using only 36 hand-signs,continuous hand-sign-spelled Bangla sign language(BdSL)recognition is *** paper presents a Bangla language modeling algorithm for automatic recognition of hand-sign-spelled Bangla sign language which consists of two *** phase is designed for hand-sign classification and the second phase is designed for Bangla language modeling algorithm(BLMA)for automatic recognition of hand-sign-spelled Bangla sign *** first phase,we have proposed two step classifiers for hand-sign classification using normalized outer boundary vector(NOBV)and window-grid vector(WGV)by calculating maximum inter correlation coefficient(ICC)between test feature vector and pre-trained feature *** first,the system classifies hand-signs using *** classification score does not satisfy specific threshold then another classifier based on WGV is *** system is trained using 5,200 images and tested using another(5,200×6)images of 52 hand-signs from 10 signers in 6 different challenging environments achieving mean accuracy of 95.83%for classification with the computational cost of 39.972 milliseconds per *** the Second Phase,we have proposed Bangla language modeling algorithm(BLMA)which discovers all"hidden characters"based on"recognized characters"from 52 hand-signs of BdSL to make any Bangla words,composite numerals and sentences in BdSL with no training,only based on the result of first *** the best of our knowledge,the proposed system is the first system in BdSL designed on automatic recognition of hand-sign-spelled BdSL for large *** system is tested for BLMA using hand-sign-spelled 500 words,100 composite numerals and 80 sentences in BdSL achieving mean accuracy of 93.50%,95.50%and 90.50%respectively.

关键词： Bangla sign language(BdSL) hand-sign classification Bangla language modeling rules(BLMR) Bangla language modeling algorithm(BLMA)

A Review on Self-healing in Modern Power Distribution Systems

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1719-1733页

作者： Seyed ali Arefifar md.Shahin Alam Abdullah Hamadi IEEE Department of Electrical and Computer Engineering Oakland UniversityRochesterUSA Department of Energy and Technology Odessa CollegeOdessaUSA School of Engineering and Technology Western Illinois UniversityMacombUSA

The ever-increasing dependence on electrical power has posed more challenges to power system engineers to deliver secure, stable, and sustained energy to electricity consumers. Due to the increasing occurrence of short-and long-term power interruptions in the power system, the need for a systematic approach to mitigate the negative impacts of such events is further manifested. Self-healing and its control strategies are generally accepted as a solution for this concern. Due to the importance of self-healing subject in power distribution systems, this paper conducts a comprehensive literature review on self-healing from existing published papers. The concept of self-healing is briefly described, and the published papers in this area are categorized based on key factors such as self-healing optimization goals, available control actions, and solution methods. Some proficient techniques adopted for self-healing improvements are also classified to have a better comparison and selection of methods for new investigators. Moreover, future research directions that need to be explored to improve self-healing operations in modern power distribution systems are investigated and described at the end of this paper.

关键词： Self-healing distributed generator renewable energy source microgrid optimization reconfiguration service restoration automation system

ARIMA With GARCH Family Modeling and Projection on Share Volume of DSE

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Economics World 2015年第4期3卷 171-184页

作者： Ahammad Hossain md. Kamruzzaman md. Ayub ali Varendra University Rajshahi Bangladesh University ofRajshahi Rajshahi Bangladesh

A suitable statistical model has been explored for the investors as well as the researchers to resolve the future estimation of share volume by using daily stock volume data from Dhaka Stock Exchange （DSE）. The daily volume data from the June 1, 2004 to April 19, 2010 were retrieved from DSE website as a secondary data source. The Maximum Likelihood---Autoregressive Conditional Heteroskedasticity （ARCH）（Marquardt） method has been applied to construct the models for the stock volume data of DSE by using statistical package software E-Views of verson-5. First of all, an ＂Auto Regressive Integrated Moving Average （ARIMA） model＂ was fitted and observed that heteroscedastic volatilities were still present there. To eliminate this dilemma, ARCH class of volatility models has been used and finally the ARIMA with EGARCH model has been explored. Findings of this study have recognized that ARIMA with EGARCH model implies low mean square error, low mean absolute error, low bias proportion, and low variance proportion for share volume data with comparing to other models. Hence, the modelling concept established in this study would be a decisive study for the investors as well as the researchers.

关键词： ARIMA Generalized ARCH (GARCH) family models stock volume projection strategy