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Communications in Theoretical Physics 2016年第9期65卷 291-296页

作者： Shah Mohammad Bahauddin mir mehedi faruk Physics and Astronomy Rice University Houston USA Theoretical Physics Blackett Laboratory Imperial College London SW7 2AZ United Kingdom Department of Theoretical Physics University of Dhaka Dhaka-1000 Banglagesh

From the unified statistical thermodynamics of quantum gases, the virial coefficients of ideal Bose and Fermi gases, trapped under generic power law potential are derived systematically. From the general result of virial coefficients, one can produce the known results in d = 3 and d = 2. But more importantly we found that, the virial coefficients of Bose and Fermi gases become identical(except the second virial coefficient, where the sign is different)when the gases are trapped under harmonic potential in d = 1. This result suggests the equivalence between Bose and Fermi gases established in d = 1(J. Stat. Phys. DOI 10.1007/s10955-015-1344-4). Also, it is found that the virial coefficients of two-dimensional free Bose(Fermi) gas are equal to the virial coefficients of one-dimensional harmonically trapped Bose(Fermi) gas.

关键词： virial coefficients quantum gas equivalence

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quantum gases power law potential grand potential condensation hierarchy

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Communications in Theoretical Physics 2016年第2期65卷 169-176页

作者： mir mehedi faruk Md.Sazzad Hossain Md.Muktadir Rahman Department of Theoretical Physics University of Dhaka Dhaka-lO00 Bangladesh Theoretical Physics Blackett Laboratory Imperial College London SW7 2AZ United Kingdom Department of Nuclear Engineering University of Dhaka Dhaka-1000 Bangladesh

The changes in characteristics of Bose condensation of ideal Bose gas due to an external generic power law potential U =∑~d_（i=1）ci｜xi/ai｜~（ni） are studied carefully. Detailed calculation of Kim et al.（J. Phys. Condens. Matter 11（1999） 10269） yielded the hierarchy of condensation transitions with changing fractional dimensionality. In this manuscript, some theorems regarding specific heat at constant volume CV are presented. Careful examination of these theorems reveal the existence of hidden hierarchy of the condensation transition in trapped systems as well.

关键词： Investigation of Bose Condensation in Ideal Bose Gas Trapped under Generic Power Law Potential in d Dimension

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Energy Fluctuation of Ideal Fermi Gas Trapped under Generic Power Law Potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) in d Dimensions

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Communications in Theoretical Physics 2016年第4期65卷 465-468页

作者： mir mehedi faruk Md.Muktadir Rahman Dwaipayan Debnath Md.Sakhawat Hossain Himel Theoretical Physics Blackett LaboratoryImperial College Department of Theoretical Physics University of Dhaka Department of Biomedical Physics and Technology University of Dhaka

Energy fluctuation of ideal Fermi gas trapped under generic power law potential U=Σ_(i=1)~d c_i|x_i/a_i|^(n_i) has been calculated in arbitrary *** fluctuation is scrutinized further in the degenerate limit μ>>K_B T with the help of Sommerfeld *** dependence of energy fluctuation on dimensionality and power law potential is studied in *** importantly our general result can not only exactly reproduce the recently published result regarding free and harmonically trapped ideal Fermi gas in d =3 but also can describe the outcome for any power law potential in arbitrary dimension.

关键词： Fermi gas power law potential energy fluctuation

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Ensemble and optimized hybrid algorithms through Runge Kutta optimizer for sewer sediment transport modeling using a data pre-processing approach

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International Journal of Sediment Research 2023年第6期38卷 847-858页

作者： Enes Gul mir Jafar Sadegh Safari Omer faruk Dursun Gokmen Tayfur Department of Civil Engineering Inonu University Department of Civil Engineering Yasar University Department of Civil Engineering Izmir Institute of Technology

Uncontrolled sediment deposition in drainage and sewer systems raises unexpected maintenance *** this end,implementation of an accurate model relying on effective parameters involved is a reliable *** this study,three machine learning techniques,namely extreme learning machine(ELM),multilayer perceptron neural network(MLPNN),and M5P model tree(M5PMT);and three optimization approaches of Runge Kutta(RUN),genetic algorithm(GA),and particle swarm optimization(PSO) are applied for *** optimization and ensemble hybridization approaches are applied in the modeling *** the case of hybrid optimized models,the ELM and MLPNN models are hybridized with RUN,GA,and PSO algorithms to develop six hybrid models of ELM-RUN,ELM-GA,ELMPSO,MLPNN-RUN,MLPNN-GA,and *** hybrid models are developed through coupling the ELM and MLPNN models with the M5PMT *** data pre-processing approach is applied to find the best randomness characteristic of the utilized *** illustrate that the RUNbased hybrid models outperform the GA-and PSO-based *** the MLPNN-RUN and MLPNN-M5PMT hybrid models generate better results than their alternatives,MLPNN-M5PMT slightly outperforms MLPNN-RUN model with a coefficient of determination of 0.84 and a root mean square error of *** current study shows the superiority of the ensemble-based approach to the optimization *** investigation is needed by considering alternative optimization techniques to enhance sediment transport modeling.

关键词： Ensemble learning Hybrid model Machine learning Open channels Sediment transport Sewer pipes