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Chinese Geographical Science 2008年第1期18卷 85-92页

作者： bahman Jabbarian AMIRI Kaneyuki NAKANE Division of Environmental Dynamics and Management Graduate School of Biosphere Science Hiroshima University 1-7-1 Kagamiyama Higashi-Hiroshima 739-8521 Japan

This study investigated the linkages between river water quality and land use in river catchments in Yama- guchi Prefecture, the western Japan, in order to examine the effect of land use changes of both entire catchment and buffer zone on river water quality. Dissolved Oxygen (DO), pH, Biological Oxygen Demand (BOD), Suspended Solids (SS), Escherichia coli, Total Nitrogen (TN) and Total Phosphorus (TP) were considered as river water quality indica- tors. Satellite images were applied to generating the land use map. Multiple regression model was applied to linking the changes in the river water quality with the land uses in both entire catchment area and buffer zone. The results in- dicate that the integrative application of land use data from the entire catchment and the buffer zone could give rise to more robust model to predict the concentrations of Suspended Solids (r2=0.88) and Total Nitrogen (r2=0.90), rather than models which separately considered land use data in catchment and buffer zone.

关键词： land use water quality buffer zone entire catchment Yamaguchi Prefecture Japan

Three-dimensional simulation of long-wavelength free-electron lasers with helical wiggler and ion-channel guiding

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Chinese Physics B 2013年第7期22卷 183-191页

作者： F. Jafari bahman B. Maraghechi Department of Physics Amirkabir University of Technology

A three-dimensional simulation of a steady-state amplifier model of a long-wavelength free-electron laser （FEL） with realizable helical wiggler and ion-channel guiding is presented. The set of coupled nonlinear differential equations for electron orbits and fields of TE 11 mode in a cylindrical waveguide are solved numerically by the Runge–Kutta algorithm with averages calculated by the Gaussian quadrature technique. Self-fields and space-charge effects are neglected, and the electron beam is assumed to be cold and slippage is ignored. The parameters correspond to the Compton regime. Evolution of the radiation power and growth rate along the wiggler is studied. Ion-channel density is chosen to obtain optimum efficiency. Simulations are preformed for the FEL operating in the neighborhood of 35 GHz and 16.5 GHz for the electron beam energies of 250 keV and 400 keV, respectively. The result of the saturated efficiency was found to be in good agreement with the simple estimation based on the phase-trapping model.

关键词： free-electron laser helical wiggler ion-channel guiding

Predictable forward performance processes in complete markets

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Probability, Uncertainty and Quantitative Risk 2023年第2期8卷 141-176页

作者： bahman Angoshtari Department of Mathematics University of MiamiCoral GablesFL 33146USA

We establish existence of Predictable Forward Performance Processes(PFPPs)in conditionally complete markets,which has been previously shown only in the binomial *** market model can be a discrete-time or a continuous-time model,and the investment horizon can be finite or *** show that the main step in construction of PFPPs is solving a one-period problem involving an integral equation,which is the counterpart of the functional equation found in the binomial *** this integral equation has been partially studied in the existing literature,we provide a new solution method using the Fourier transform for tempered *** also provide closedform solutions for PFPPs with inverse marginal functions that are completely monotonic and establish uniqueness of PFPPs within this *** apply our results to two special *** first one is the binomial market and is included to relate our work to the existing *** second example considers a generalized Black–Scholes model which,to the best of our knowledge,is a new result.

关键词： Forward performance processes Predictable preference Complete market Integral equation Completely monotonic inverse marginal Deconvolution Fourier transform

A New Extension of Chen Distribution with Applications to Lifetime Data

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Communications in Mathematics and Statistics 2021年第1期9卷 23-38页

作者： bahman Tarvirdizade Mohammad Ahmadpour Department of Mathematics Maku BranchIslamic Azad UniversityMakuIran

In this paper,we introduce a new lifetime distribution with increasing,decreasing and bathtub-shaped hazard rate function which is constructed by compounding of the Weibull and Chen distributions and is called Weibull–Chen(W–C)*** new distribution is more flexible to model the bathtub-shaped hazard rate data,and its hazard rate function is *** study its statistical properties including quantiles,moments,order statistics and Renyi *** estimation of parameters by maximum likelihood method is discussed,and a Monte Carlo simulation study is conducted to investigate the performance of the maximum likelihood ***,it is shown that the proposed distribution fits two real lifetime data better than other distributions.

关键词： Chen distribution Weibull distribution Maximum likelihood estimation Lifetime data analysis

Nanomagnetic Organogel Based on Dodecyl Methacrylate for Absorption and Removal of Organic Solvents

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Chinese Journal of Polymer Science 2019年第5期37卷 444-450页

作者： Hossein Ghasemzadeh Maryam Dargahi Ghazaleh Eyvazi bahman Vasheghani Farahani Department of Chemistry Faculty of ScienceImam Khomeini International University

A novel nanomagnetic organogel was synthesized by in situ emulsion polymerization-crosslinking method using dodecyl methacrylate(DDMA) and styrene(St) as monomers, divinylbenzene(DVB) as a crosslinking agent, azobisisobutyronitrile(AIBN) as an initiator, and Fe_3O_4 as a nanomagnetic particle. Modification of the network was carried out by inclusion of the multi-walled carbon nanotubes(MWCNT) into the organogel matrix. The structure of the nanocomposite was characterized using FTIR spectroscopy, SEM,TEM, TGA/DTG, VSM, and BET analysis. The effects of various parameters such as the amount of crosslinker, initiator, Fe_3O_4, and reaction time as well as monomer ratio on the oil absorption of the organogel were studied. The synthesized organogel can absorb about35.5, 22.1, 29.86, 14.58, 17.6, 15.3, and 13.7 g·g^(-1) of CHCl_3, toluene, CH_2Cl_2, hexane, crude oil, gasoline, and diesel oil, under the optimized polymerization conditions, respectively. The nanocomposite organogels can be easily separated by a magnetic field after absorption of organic solvents.

关键词： Nanomagnetic organogel Dodecyl methacrylate Styrene Crosslinking MWCNT

Mechanochemical preparation and structural characterization of Ta-doped chlorapatite nanopowders

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Progress in Natural Science:Materials International 2016年第6期26卷 546-554页

作者： bahman Nasiri-Tabrizi Wan Jefrey Basirun Belinda Pingguan-Murphy Advanced Materials Research Center Materials Engineering DepartmentNajafabad BranchIslamic Azad University Department of Chemistry Faculty of ScienceUniversity of Malaya Department of Biomedical Engineering Faculty of EngineeringUniversity of Malaya

Nanocrystalline tantalum-doped chlorapatite（Ta-doped ClA） was successfully synthesized using a facile mechanochemical method. In the absence of the dopant, milling for 3 h led to the formation of a poorly crystalline hydroxyapatite, while in its presence of the Ta dopant, Ta-doped ClA nanopowders were produced as a result of an oncoming reaction. The results indicated that lattice micro-strain, crystallite size, crystallinity level, phase percentage and hexagonal lattice constants of the substituted apatite nanopowders were dramatically affected by the doping concentration. The a-axis and unit cell volume increased with the increase in the doping concentration, owing to the ionic radius difference of Cl;and OH;ions. From the TEM observations, the doped powders consisted of nanoneedles with a mean size of 60 ± 20 nm in length and 14 ±4 nm in width.

关键词： Mechano-synthesis Structural features Lattice constants XRD-Rietveld refinement Ta-doped ClA

Characterization of single-crystal fluorapatite nanoparticles synthesized via mechanochemical method

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Particuology 2011年第5期9卷 537-544页

作者： Reza Ebrahimi-Kahrizsangi bahman Nasiri-Tabrizi Akbar Cham Materials Engineering Department Najafabad Branch Islamic Azad University

The synthesis of nanostructured fiuorapatite （FA; Calo（PO4）6F2） was explored from the starting materials of CaHPO4, Ca（OH）2, CaO, P205 and CaF2 via a mechanochemical process. In this research, the suitability of using the mechanochemical process to prepare a high crystalline phase of FA was studied. The characterization and structural features of the synthesized powders were evaluated using powder X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FT-IR）, energy dispersive X-ray spectroscopy （EDX）, scanning electron microscopy （SEM）, and transmission electron microscopy （TEM） techniques. The results from the structural studies indicate that the maximum lattice disturbance in the apatite structure after the mechanochemical process was at the （0 0 2） plane. Furthermore, the maximum particle size was below the crystallite size after 60 h of milling and subsequent thermal treatment at 600 ℃ for 1 h （heated up to 600 ℃ and kept for 1 h at this temperature）. We determined that this method gives rise to the single-crystal FA with an average size in the range of 25 ± 5 to 29 ± 9 rim. The present findings suggest that the solid-state reaction and appropriate thermal process simultaneously lead to the formation of nanostructured FA with spheroidal shape.

关键词： Fluorapatite Single-crystal Nanoparticles Mechanochemical Crystallinity

Advances in Manta Ray Foraging Optimization:A Comprehensive Survey

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Journal of Bionic Engineering 2024年第2期21卷 953-990页

作者： Farhad Soleimanian Gharehchopogh Shafi Ghafouri Mohammad Namazi bahman Arasteh Department of Computer Engineering Urmia BranchIslamic Azad UniversityUrmiaIran Department of Computer Engineering Tabriz BranchIslamic Azad UniversityTabrizIran Department of Computer Engineering Maybod BranchIslamic Azad UniversityMaybodIran Department of Software Engineering Faculty of Engineering and Natural ScienceIstinye UniversityIstanbulTurkey

This paper comprehensively analyzes the Manta Ray Foraging Optimization(MRFO)algorithm and its integration into diverse academic *** in 2020,the MRFO stands as a novel metaheuristic algorithm,drawing inspiration from manta rays’unique foraging behaviors—specifically cyclone,chain,and somersault *** biologically inspired strategies allow for effective solutions to intricate physical *** its potent exploitation and exploration capabilities,MRFO has emerged as a promising solution for complex optimization *** utility and benefits have found traction in numerous academic *** its inception in 2020,a plethora of MRFO-based research has been featured in esteemed international journals such as IEEE,Wiley,Elsevier,Springer,MDPI,Hindawi,and Taylor&Francis,as well as at international conference *** paper consolidates the available literature on MRFO applications,covering various adaptations like hybridized,improved,and other MRFO variants,alongside optimization *** trends indicate that 12%,31%,8%,and 49%of MRFO studies are distributed across these four categories respectively.

关键词： Manta ray foraging optimization Metaheuristic algorithms Hybridization Improved Optimization

An equivalent linearization method for nonlinear Van der Pol oscillator subjected to random vibration using orthogonal functions

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Control Theory and Technology 2018年第1期16卷 49-57页

作者： Amir YOUNESPOUR Hosein GHAFFARZADEH bahman Farahmand AZAR Faculty of Civil Engineering University of Tabriz Tabriz 51666 Iran

This paper deals with the idea of the orthogonal functions in the equivalent linearization of the nonlinear systems. Block Pulse （BP） function gives effective tools to approximate complex problems. The aim of this work is on using properties of the BP function as an orthogonal function in process of linearization. The BP functions have been used to propose an equivalent linearization method in the time domain to determine the unknown linearization coefficients. The accuracy of the proposed method compared with the other equivalent linearization approaches, including the regulation linearization and the dual criterion linearization methods. This study exploited the nonlinear Van der Pol oscillator system under stationary random excitation to demonstrate the feasibility of the proposed method. The validity of the analytical method is verified by applying different values of nonlinearity and intensity of excitation. Besides, by comparing the mean-square responses and frequency response functions of the linearized systems for a wide range of nonlinearity depicted the present method is in agreement with other methods.

关键词： Nonlinear system equivalent linearization orthogonal functions Van der Pol oscillator random vibration

Viscosity prediction in selected Iranian light oil reservoirs:Artificial neural network versus empirical correlations

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Petroleum Science 2013年第1期10卷 126-133页

作者： Mohammad Soleimani Lashkenari Majid Taghizadeh bahman Mehdizadeh Chemical Engineering Department Babol University of Technology National Iranian South Oil Company

Viscosity is a parameter that plays a pivotal role in reservoir fluid estimations. Several approaches have been presented in the literature （Beal, 1946; Khan et al, 1987; Beggs and Robinson, 1975; Kartoatmodjo and Schmidt, 1994; Vasquez and Beggs, 1980; Chew and Connally, 1959; Elsharkawy and Alikhan, 1999; Labedi, 1992） for predicting the viscosity of crude oil. However, the results obtained by these methods have significant errors when compared with the experimental data. In this study a robust artificial neural network （ANN） code was developed in the MATLAB software environment to predict the viscosity of Iranian crude oils. The results obtained by the ANN and the three well-established semi-empirical equations （Khan et al, 1987; Elsharkawy and Alikhan, 1999; Labedi, 1992） were compared with the experimental data. The prediction procedure was carried out at three different regimes： at, above and below the bubble-point pressure using the PVT data of 57 samples collected from central, southern and offshore oil fields of lran. It is confirmed that in comparison with the models previously published in literature, the ANN model has a better accuracy and performance in predicting the viscosity of Iranian crudes.

关键词： Viscosity crude oil artificial neural network empirical equations