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Auto-tuning PVT data using multi-objective optimization:Application of NSGA-II algorithm

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Petroleum 2024年第1期10卷 135-149页

作者： Abdolhadi Zarifi mohammad Madani mohammad Jafarzadegan Reservoir Engineering Systems Petroleum Engineering DepartmentMain Office Building of National Iranian South Oil Company(NISOC)AhvazIran Reservoir Engineering Division Petroleum Engineering DepartmentPetroleum Engineering and Development Company(PEDEC)TehranIran Combined Planning Management National Iranian Oil Company(NIOC)TehranIran

Reservoir simulation is known as perhaps the most widely used,accurate,and reliable method for field development in the petroleum *** integral part of a reliable reservoir simulation process is to consider robust and rigorous tuned EOS ***,EOS models are tuned iteratively through arduous workflows against experimental PVT ***,this comes with a number of drawbacks such as forcingly using weight factors,which upon alteration adversely affects the optimization *** objective of the current work is thus to introduce an auto-tune PVT matching tool using NSGA-II multi-objective *** order to illustrate the robustness of the presented technique,three different PVT samples are used,including two black-oil and one gas condensate *** utilize PengRobinson EOS during all the manual and auto-tuning *** of auto-tuned EOS-generated results with those of experimental and computed statistical error values for these samples clearly show that the proposed method is *** addition,the proposed method,contrary to the manual matching process,provides the engineer with several matched solutions,which allows them to select a match based on the engineering background to be best amenable to the problem at *** addition,the proposed technique is fast,and can output several solutions within less time compared to the traditional manual matching method.

关键词： Auto-tuning PVT Equation of state NSGA-II Multi-objective optimization

Enhanced removal of nitrate and phosphate from wastewater by Chlorella vulgaris: Multi-objective optimization and CFD simulation

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Chinese Journal of Chemical Engineering 2019年第3期27卷 639-648页

作者： mohammad Bagher Sabeti mohammad Amin Hejazi Afzal Karimi Faculty of Chemical and Petroleum Engineering University of Tabriz Department of Food Biotechnology Branch for Northwest & West Region Agricultural Biotechnology Research Institute of Iran Agricultural Education and Extension Organization (AREEO) Department of Biotechnology Faculty of Advanced Technologies in Medicine Iran University of Medical Sciences

To enhance the efficiency of wastewater biotreatment with microalgae, the effects of physical parameters need to be investigated and optimized. In this regard, the individual and interactive effects of temperature, p H and aeration rate on the performance of biological removal of nitrate and phosphate by Chlorella vulgaris were studied by response surface methodology(RSM). Furthermore, a multi-objective optimization technique was applied to the response equations to simultaneously find optimal combinations of input parameters capable of removing the highest possible amount of nitrate and phosphate. The optimal calculated values were temperature of 26.3 °C, pH of 8 and aeration rate of 4.7 L·min^(-1). Interestingly, under the optimum condition, approximately 85% of total nitrate and 77% of whole phosphate were removed after 48 h and 24 h, respectively, which were in excellent agreement with the predicted values. Finally, the effect of baffle on mixing performance and, as a result, on bioremoval efficiency was investigated in Stirred Tank Photobioreactor(STP) by means of Computational Fluid Dynamics(CFD). Flow behavior indicated substantial enhancement in mixing performance when the baffle was inserted into the tank. Obtained simulation results were validated experimentally. Under the optimum condition, due to proper mixing in baffled STP, nitrate and phosphate removal increased up to 93% and 86%,respectively, compared to unbaffled one.

关键词： Nitrate Phosphate Nutrient removal Response surface methodology Stirred Tank Photobioreactor Computational Fluid Dynamics

Evaluation of seismic reliability of gravity dam-reservoirinhomogeneous foundation coupled system

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 701-715页

作者： Hamid Taghavi GANJI mohammad ALEMBAGHERI mohammad Houshmand KHANEGHAHI Department of Civil and Environmental Engineering Amirkabir University of TechnologyTehranIran Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran Department of Civil Engineering Shahid Beheshti UniversityTehranIran

The seismic performance of gravity dam-reservoir-foundation coupled system is investigated utilizing probabilistic *** this research,the uncertainties associated with modeling parameters are incorporated in nonlinear response history simulations to realistically quantify their effects on the seismic performance of the *** methodology is applied to Pine Flat gravity dam and the foundation is considered to be inhomogeneous assuming a constant spatial geometry but with various rock material *** sources of uncertainty are taken into account in the reliability analysis using Latin Hypercube Sampling *** effects of the deconvolution process,number of samples,and foundation inhomogeneity are investigated.

关键词： gravity dams dam-reservoir-foundation interaction seismic reliability inhomogeneous foundation earthquake deconvolution

Production of ultra-transparent glass-ceramics via controlled crystallization of nanocrystals in the glassy matrix of LAST

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International Journal of Minerals,Metallurgy and Materials 2014年第1期21卷 71-76页

作者： mohammad Sadegh Shakeri Materials and Energy Research Center(MERC)

Microstructural variation in glass-ceramics encompasses the range from nanocrystalline transparent materials to microcrystalline tough materials. In this investigation, the crystallization process was controlled for the development of ultra transparent LiEO-A1203-SiO2 glass-ceramics containing TiO2 as a nucleating agent （LAST）. Results of UV-Vis absorption spectra were compared with the expected theo- retical values calculated by the Rayleigh scattering method for the determination of ultra transparency. Results of the investigation illustrate that the control of crystallization increases the range of ultra transparency by the reduction of crystal size and their uniformity in the glassy matrix. Last but not the least, the optimized samples are ultra transparent approximately in the whole light wavelengths.

关键词： glass-ceramics transparency nanocrystals crystallization

Geometrically Nonlinear Bending Analysis of Metal-Ceramic Composite Beams under Thermomechanical Loading

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 701-713页

作者： TORABIZADEH mohammad Amin Department of Industrial Design Engineering University of Applied Science and Technology

A new method is developed to derive equilibrium equations of Metal-Ceramic beams based on first order shear deformation plate theory which is named first order shear deformation beam theory2(FSDBT2). Equilibrium equations obtained from conventional method (FSDBT1) is compared with FSDBT2 and the case of cylindrical bending of Metal-Ceramic composite plates for non-linear thermomechanical deformations and various loadings and boundary conditions. These equations are solved by using three different methods (analytical, perturbation technique and finite element solution). The through-thickness variation of the volume fraction of the ceramic phase in a Metal-Ceramic beam is assumed to be given by a power-law type function. The non-linear strain-displacement relations in the von-Kármán sense are used to study the effect of geometric non-linearity. Also, four other representative averaging estimation methods, the linear rule, Mori-Tanaka, Self-Consistent and Wakashima-Tsukamoto schemes, by comparing with the power-law type function are also investigated. Temperature distribution through the thickness of the beams in thermal loadings is obtained by solving the one-dimensional heat transfer equation. Finally it is concluded that for Metal-Ceramic composites, these two theories result in identical static responses. Also the displacement field and equilibrium equations in the case of cylindrical bending of Metal-Ceramic plates are the same as those supposed in FSDBT2.

关键词： thermomechanical loading functionally graded beams monlinear analysis analytical solution

Hierarchical data replication strategy to improve performance in cloud computing

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Frontiers of Computer Science 2021年第2期15卷 63-79页

作者： Najme MANSOURI mohammad Masoud JAVIDI Behnam mohammad Hasani ZADE Department of Computer Science Shahid Bahonar University of KermanKerman76169-14111Iran Mahani Mathematical Research Center Shahid Bahonar University of KermanKerman76169-14111Iran

Cloud computing environment is getting more interesting as a new trend of data *** replication has been widely applied to improve data access in distributed systems such as Grid and ***,due to the finite storage capacity of each site,copies that are useful for future jobs can be wastefully deleted and replaced with less valuable ***,it is considerable to have appropriate replication strategy that can dynamically store the replicas while satisfying quality of service(QoS)requirements and storage capacity *** this paper,we present a dynamic replication algorithm,named hierarchical data replication strategy(HDRS).HDRS consists of the replica creation that can adaptively increase replicas based on exponential growth or decay rate,the replica placement according to the access load and labeling technique,and finally the replica replacement based on the value of file in the *** evaluate different dynamic data replication methods using CloudSim *** demonstrate that HDRS can reduce response time and bandwidth usage compared with other *** means that the HDRS can determine a popular file and replicates it to the best *** method avoids useless replications and decreases access latency by balancing the load of sites.

关键词： cloud computing data replication multi-tier architecture simulation load balance

Chaos in a fractional-order micro-electro-mechanical resonator and its suppression

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Chinese Physics B 2012年第10期21卷 159-167页

作者： mohammad Pourmahmood Aghababa Electrical Engineering Department Urmia University of TechnologyUrmiaIran

The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exhibits *** attractors of the system are plotted to validate its chaotic ***,a novel fractional finite-time controller is introduced to suppress the chaos of the FOMEMRS with model uncertainties and external disturbances in a given finite *** the latest version of the fractional Lyapunov theory,the finite time stability and robustness of the proposed scheme are ***,we present some computer simulations to illustrate the usefulness and applicability of the proposed method.

关键词： micro-electro-mechanical resonator chaotic behavior fractional calculus fractional finite-time controller

Optimization of a continuous ultrasound assisted oxidative desulfurization(UAOD) process of diesel using response surface methodology(RSM) considering operating cost

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Chinese Journal of Chemical Engineering 2020年第5期28卷 1384-1396页

作者： mohammad Dana mohammad Amin Sobati Shahrokh Shahhosseini Aminreza Ansari School of Chemical Engineering Iran University of Science and Technology(IUST)TehranIran

A continuous-flow ultrasound-assisted oxidative desulfurization(UAOD)of partially hydro-treated diesel has been investigated using hydrogen peroxide-formic acid as simple and easy to apply oxidation *** effects of different operating parameters of oxidation stage including residence time(2–24 min),formic acid to sulfur molar ratio(10–150),and oxidant to sulfur molar ratio(5–35)on the sulfur removal have been studied using response surface methodology(RSM)based on Box–Behnken *** the operating costs of the continuous-flow oxidation stage including chemical and electrical energy consumption,the appropriate values of operating parameters were selected as follows:residence time of 16 min,the formic acid to sulfur molar ratio of 54.47,and the oxidant to sulfur molar ratio of *** these conditions,the sulfur removal and the volume ratio of the hydrocarbon phase to the aqueous phase were 86.90%and 4.34,*** drastic reduction in the chemical consumption in the oxidation stage,the volume ratio of the hydrocarbon phase to the aqueous phase was increased up to ***,the formic acid to sulfur molar ratio and the oxidant to sulfur molar ratio were obtained 23.64 and 3.58,respectively,which lead to sulfur removal of 84.38%with considerable improvements on the operating cost of oxidation stage in comparison with the previous works.

关键词： Ultrasound-Assisted Oxidative Desulfurization(UAOD) Continuous-flow system Sulfur removal Response Surface Methodology(RSM) Operating cost

A Galvanostatic Modeling for Preparation of Electrodeposited Nanocrystalline Coatings by Control of Current Density

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Journal of Materials Science & Technology 2012年第12期28卷 1071-1076页

作者： Ali mohammad Rashidi School of Engineering Razi UniversityP.O. Box 67149-67346 Kermanshah Iran

The correlation between the grain size of electrodeposited coatings and the current densities was modeled by considering galvanostatic conditions. In order to test the model by experimental results, nanocrystalline （NC） nickel samples were deposited at different current densities using a Watts bath. The grain size of the deposits was evaluated by X-ray diffraction （XRD） technique. Model predictions were validated by finding a curve being the best-fit to the experimental results which were gathered from literature for different NC coatings in addition to those data measured in this research for NC nickel coatings. According to our model, the variation of grain size with the reciprocal of the current density follows a power law. A good agreement between the experimental results and model predictions was observed which indicated that the derived analytical model is applicable for producting the nanocrystalline electrodeposits with the desired grain size by controling current density.

关键词： Electrodeposition Galvanostatic modeling Grain size control Nanocrystalline