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Journal of Materials Science & Technology 2012年第2期28卷 125-131页

作者： ali Parsapour Saied Nouri Khorasani mohammad Hossein Fathi Department of Materials Engineering Isfahan University of Technology Department of Chemical Engineering Isfahan University of Technology

Surface engineering technology is a suitable method for coatings on the metal surfaces or performing surface modification treatment, which can improve corrosion resistance and biocompatibility of metals. In this research, corrosion behavior of Nb coating on H2SO4 and HNO3 treated aiSI stainless steel 316L （SS） was evaluated. Nb coating was carried out using physical vapor deposition process on the SS. Characterization techniques including scanning electron microscopy （SEM） and energy dispersive X-ray （EDX） technique were used to investigate the microstructure and morphology of the coated and treated SS. Electrochemical potentiodynamic tests were performed in two types of physiological solutions and compared with the pristine SS specimens. Cyclic polarization tests were performed to evaluate resistivity against pitting. Experimental results indicate that Nb coating and surface treatment of the SS had a positive effect on improvement of corrosion behavior. The decrease in corrosion current densities was significant for coated and treated specimens. The corrosion current density was much lower than the values obtained for pristine specimens.

关键词： 316L stainless steel Corrosion behavior Nb coating Surface treatment

A GIS-based time-dependent seismic source modeling of Northern Iran

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 33-45页

作者： Mahdi Hashemi ali Asghar Alesheikh mohammad Reza Zolfaghari School of Information Seiences University of Pittsburgh Pittsburgh Pennsylvania 15260 USA Department of Geospatial Information Systems K.N. Toosi University of Technology Tehran 19697 Iran Civil Engineering Department K.N. Toosi Universiry of Technology Tehran 19697 Iran

： The first step in any seismic hazard study is the definition of seismogenic sources and the estimation of magnitude-frequency relationships for each source. There is as yet no standard methodology for source modeling and many researchers have worked on this topic. This study is an effort to define linear and area seismic sources for Northern Iran. The linear or fault sources are developed based on tectonic features and characteristic earthquakes while the area sources are developed based on spatial distribution of small to moderate earthquakes. Time-dependent recurrence relationships are developed for fault sources using renewal approach while time-independent frequency-magnitude relationships are proposed for area sources based on Poisson process. GIS functionalities are used in this study to introduce and incorporate spatial- temporal and geostatistical indices in delineating area seismic sources. The proposed methodology is used to model seismic sources for an area of about 500 by 400 square kilometers around Tehran. Previous researches and reports are studied to compile an earthquake/fault catalog that is as complete as possible. All events are transformed to uniform magnitude scale; duplicate events and dependent shocks are removed. Completeness and time distribution of the compiled catalog is taken into account. The proposed area and linear seismic sources in conjunction with defined recurrence relationships can be used to develop time-dependent probabilistic seismic hazard analysis of Northern Iran.

关键词： seismic source modeling geostatistical index seismic hazard GIS

Intelligent Petroleum Engineering

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Engineering 2022年第11期18卷 27-32页

作者： mohammad ali Mirza Mahtab Ghoroori Zhangxin Chen Department of Chemical and Petroleum Engineering University of CalgaryCalgaryAB T2N 1N4Canada

Data-driven approaches and artificial intelligence(ai)algorithms are promising enough to be relied on even more than physics-based methods;their main feed is data which is the fundamental element of each *** algorithms learn from data and unveil unseen patterns out of it The petroleum industry as a realm where huge volumes of data are generated every second is of great interest to this new *** the oil and gas industry is in the transition phase to oilfield digitization,there has been an increased drive to integrate data-driven modeling and machine learning(ML)algorithms in different petroleum engineering *** has been widely used in different areas of the *** extensive studies have been devoted to exploring ai applicability in various disciplines of this industry;however,lack of two main features is *** of the research is either not practical enough to be applicable in real-field challenges or limited to a specific problem and not *** must be given to data itself and the way it is classified and *** there are sheer volumes of data coming from different disciplines,they reside in departmental silos and are not accessible by *** order to derive as much insight as possible out of data,the data needs to be stored in a centralized repository from where the data can be readily consumed by different applications.

关键词： Artificial intelligence Machine learning Intelligent reservoir engineering Text mining Intelligent geoscience Intelligent drilling engineering

Modeling and optimization of the parameters affecting the in-situ microencapsulation process for producing epoxy-based self-healing anti-corrosion coatings

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Particuology 2018年第1期16卷 59-69页

作者： ali Ebrahiminiya mohammad Khorram Shadi Hassanajili Mehdi Javidi School of Chemical and Petroleum Engineering Shiraz University Shiraz lran Department of Materials Science and Engineering School of Engineering Shiraz University Shiraz lran

Micro/nanocapsules of urea-formaldehyde resin loaded with linseed oil, which are a self-healing agent in glass flake epoxy anti-corrosion paint, were prepared using a combination of ultrasonic homogenization and in-situ polymerization. The main objective of this study was to model and optimize the microen- capsulation process. Five-level central composite design was used to design, model, and optimize the microencapsulation process. A quadratic model was constructed to show the dependency of the per- centage of encapsulated linseed oil and capsule size, as model responses, on the studied independent variables （the rotational speed of the agitator and the power and duration of sonication）. Analysis of vari- ance showed that all of the variables have significant effects on the encapsulated linseed oil percentage, while the rotational speed of the agitator and sonication time is effective variables for controlling the capsule size. Under the determined optimum conditions, a maximum encapsulated linseed oil percentage （ELO%） of 93.9% and a minimum micro/nanocapsule size of 0.574 μm were achieved at 594 rpm agitation, 350 W sonication power, and 3 min sonication time. Validation of the model was performed. The percent- age relative errors between the predicted and experimental values of the ELO% and micro/nanocapsule size are 1.28% and 3.66%, respectively. The efficacy of the optimum micro/nanocapsules in healing cracks in a glass flake epoxy paint and corrosion protection was investigated by the salt spray test and Tafel polarization technique.

关键词： Urea-formaldehyde Response surface methodology Central composite design Ultrasonic homogenization Linseed oil Self-healing coating

aircraft robust multidisciplinary design optimization methodology based on fuzzy preference function

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Chinese Journal of Aeronautics 2018年第12期31卷 2248-2259页

作者： ali Reza BABAEI mohammad Reza SETAYANDEH Hamid FARROKHFAL Department of Mechanical and Aerospace Engineering Malek-Ashtar University of Technology

This paper presents a Fuzzy Preference Function-based Robust Multidisciplinary Design Optimization(FPF-RMDO) methodology. This method is an effective approach to multidisciplinary systems, which can be used to designer experiences during the design optimization process by fuzzy preference functions. In this study, two optimizations are done for Predator MQ-1 Unmanned Aerial Vehicle(UAV):(A) deterministic optimization and(B) robust optimization. In both problems, minimization of takeoff weight and drag is considered as objective functions, which have been optimized using Non-dominated Sorting Genetic Algorithm(NSGA). In the robust design optimization, cruise altitude and velocity are considered as uncertainties that are modeled by the Monte Carlo Simulation(MCS) method. Aerodynamics, stability and control, mass properties, performance, and center of gravity are used for multidisciplinary analysis. Robust design optimization results show 46% and 42% robustness improvement for takeoff weight and cruise drag relative to optimal design respectively.

关键词： Fuzzy logic Multidisciplinary design optimization Preference function Robust design Unmanned Aerial Vehicle(UAV)

Experimental study of a heavy fuel oil atomization by pressure-swirl injector in the application of entrained flow gasifier

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Chinese Journal of Chemical Engineering 2019年第4期27卷 765-771页

作者： Pouria Mikaniki Seyed mohammad ali Najafi Hojat Ghassemi School of Mechanical Engineering Iran University of Science and Technology

The available SMD(Sauter mean diameter) correlations on pressure-swirl injectors predict droplet sizing very different from each other, especially for heavy fuels. Also there was a lack in the literature for comparing available correlations. So an experimental study was conducted on a heavy fuel oil(HFO) spray, Mazut 380. A pressure swirl injector was designed and fabricated. The experiments for Mazut at 40℃ and 80℃ were compared with the results for water, including spray half cone angle, breakup length and mean droplet diameter,at different injection pressures. Lower spray angle, higher breakup length and larger droplets were observed for lower injection pressures and higher liquid viscosity. SMD was about 75 μm for water and about 87 μm for Mazut at 80℃. The results for droplet mean diameter were also compared with correlations from previous studies on pressure swirl atomizers. The SMD results show that for water spray, LISA method was in good agreement,also Babu and Ballester correlations were successful when high viscosity fluid was injected.

关键词： Atomization Pressure-swirl injector Mazut Size distribution Fuel Viscosity

Fuzzy model prediction of Co(Ⅲ)/Al_2O_3 catalytic behavior in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2011年第6期20卷 603-610页

作者： mohammad ali Takassi Mahdi Koolivand Salooki Morteza Esfandyari Department of Science Petroleum CollegePetroleum University of Technology Oil&Gas Processing Center of Excellence Chemical Engineering DepartmentUniversity of Tehran Department of Chemical Engineering Faculty of EngineeringFerdowsi University of Mashad

The application of Co（Ⅲ）/Al2O3 catalyst in Fischer-Tropsch synthesis（FTS）was studied in a wide range of synthesis gas conversions and compared with Fuzzy Simulation *** study applies fuzzy model to predicting the product composition of CH4,CO2 and CO in Fischer-Tropsch process for natural gas synthesis,in which the input vector was 4-dimension including four variables（operating pressure, operating temperature,time and CO/H2 ratio）of 70 different experiments and the output product is a composition of CO2,CO and CH4. The Mamdani algorithm has been applied to the training of the fuzzy system and the test set was used to evaluate the performance of the system including R2,ARE,AARE and *** results demonstrated that the predicted values from the model were in good consistency with the experimental *** work indicates how fuzzy inference system（FIS）,as a promising predicting technique,would be effectively used in FTS.

关键词： fuzzy inference system Fischer-Tropsch natural gas catalyst Co (III) Al2O3

Corrosion Behavior and Biocompatibility of Hydroxyapatite Coating on H_2SO_4 Passivated 316L SS for Human Body Implant

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 409-415页

作者： ali Parsapour Saied Nouri Khorasani mohammad Hossein Fathi Biomaterials Research Center Department of Chemical Engineering Isfahan University of Technology Department of Materials Engineering Isfahan University of Technology

The aim of this studies at simultaneous improvement of the corrosion behavior and biocompatibility of metallic implant and bone Osseointegration simultaneously. Stainless steel 316L （SS） was used as metallic substrate and after surface treatment with 15 vol.% sulfuric acid, it was coated with hydroxyapatite coating employing plasma - spraying process. Structure characterization techniques including XRD, SEM and EDX were also utilized to investigate the microstructure, morphology, and crystallinity of the coating. Electrochemical potentiodynamic tests were performed in two types of physiological solutions in order to determine and compare the corrosion resistance behavior of the coated and uncoated specimens as an indication of biocompatibility. The results indicate that the surface treatment and hydroxyapatite coating improve the corrosion resistance behavior of SS. The corrosion current density of the surface treated and the hydroxyapatite coated SS also decrease. These also show that surface treated and hydroxyapatite coated SS can be used as human body implants with the goals of corrosion resistance improvement （biocompatibility） and bone osseointegration.

关键词： Surface treatment Hydroxyapatite coating Corrosion behavior Plasma spray Stainless steel 316L Human body implant

Task Allocation Approach for Minimizing Make-Span inWireless Sensor Actor Networks

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Computer Systems Science & Engineering 2021年第11期39卷 165-178页

作者： mohammad Reza Okhovvat mohammad Taghi Kheirabadi ali Nodehi Morteza Okhovvat Department of Computer Engineering Gorgan BranchIslamic Azad UniversityGorganIran Health Management and Social Development Research Center Golestan University of Medical SciencesGorganIran

Wireless Sensor Actor Networks(WSANs)have contributed to the development of pervasive computing wherein time consideration to perform the tasks of pervasive applications is ***,time constraint is one of the major challenges of *** this paper,we propose an analytical approach based on queuing theory to minimize the total time taken for completion of tasks,i.e.,make-span,in WSANs with hybrid *** best allocation rates of tasks to actor nodes are figured out through solving inequities and qualities resulting from a steady state analysis of the proposed *** the calculated tasks arrival rates at each of the actors,the make-span could be *** assess the accuracy of the tasks assignment rates to each of the actors attained from the suggested analytical approach and to provide a graphical representation of the WSAN a formal model in terms of the generalized stochastic Petri net(GSPN)is *** proposed GSPN model is analyzed,tasks distribution weights to the actors are determined,and then tasks allocation rates can be *** the results achieved from the analytical approach and the GSPN model demonstrates that allocation rates and hence,the make-span figured out from proposed approach and the formal model are the *** results in typical scenarios show shorter make-span and longer network lifetime compared to when one of the two popular traditional task allocation algorithms,namely,opportunistic load balancing(OLB),and stochastic allocation(SA)algorithms,is used.

关键词： GSPN make-span optimization queuing system task allocation

Sediment settling in the Latian Dam in Iran

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International Journal of Sediment Research 2014年第2期29卷 208-217页

作者： Farhang BEHRANGI mohammad ali BANIHASHEMI Shayesteh MAHANI mohammad Reza RAHMANIAN Hydraulic Structures School of Civil EngineeringCollege of EngineeringUniversity of TehranPO Box 11365-4563TehranIran Ph.D.Student School of Civil Engineering College of EngineeringUniversity of TehranPO Box 11365-4563TehranIran.Assoc.Prof. Department of Civil Engineering the City College of New YorkNew YorkUSA.Assis.Prof. Department of Civil Engineering Shahrood University of TechnologyShahroodIran.Assis.Prof.

Among the difficulties that influence future dam operations,reservoir sedimentation is the most problematic for *** study predicted the amount and pattern of sedimentation for use in estimation of the useful lifespan of reservoirs and identification of optimal locations for outlets and intakes at the initial stages of dam *** surveys of different dams can provide better insight into this *** Dam in Iran has conducted hydrographic surveys during 7 time *** amount and process of sedimentation in this reservoir were determined,and predictions of distribution of sediments were validated by well-known,common *** formation of a delta in the reservoir was investigated for different time periods after *** problems due to the impacts of sedimentation on dam operation and the useful lifespan of the reservoir were *** addition,the study results may be used for developing empirical methods to predict sedimentation patterns in other reservoirs.

关键词： Sedimentation Dams Reservoirs Latian Dam Empirical methods Delta