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Formation and Characterization of Titanium Modified Aluminide Coatings on IN738LC

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Formation and Characterization of Titanium Modified Aluminid...

A simple kinetic model for oxidative coupling of methane over La_(0.6)Sr_(0.4)Co_(0.8)Fe_(0.2)O_(3-δ) nanocatalyst

14～(th) Congress of International Federation for Heat Treament and Surface Engineering

作者： mohammad moradi Fakhreddin Ashrafizadeh Iranian Surface Research ＆ Engineering Centre （ISREC） Isfahan Iran Dept.of Materials Engineering Isfahan University of Technology IsfahanIran

＜正＞ Up to now, the aluminide coatings used to protect industrial components at high temperature and corrosive environments have been modified by Pt, Cr, Si and Ni. In this investigation, aluminide coatings were modified by titanium and the microstructural feature and formation mechanism were evaluated. The coatings were formed on a Ni-based superalloy（IN738LC） by a two stage process including titanizing at first and aluminizing thereafter. Pack cementation titanizing performed at temperatures 950℃and 1050℃in several mixtures of Ti, Al2O3 and NH4Cl. At the second stage, aluminum diffused into surface of the specimens by an industrial aluminizing process known as Elcoat101（4 hrs at 1050℃）. The modified coatings were characterized by means of standard optical microscopy, scanning electron microscopy, energy dispersive spectroscopy and X-Ray diffraction methods. The results show that Ti in the coatings is mainly present in the form of TiNi and Al67Cr8Ti25. Titanium modified coatings grew with a mechanism similar to simple aluminizing;this includes inward diffusion of Al from the pack to the substrate and then outward diffusion of Ni from the substrate to the coating. The advantages and characteristics of this two-stage modified coating is discussed and the process parameters are proposed to obtain a coating of optimum microstructure.

关键词： diffusion coating titanium aluminide superalloy pack cementation

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Journal of Natural Gas Chemistry 2011年第3期20卷 325-333页

作者： Ali Farsi Sattar Ghader Ali moradi Seyed Soheil Mansouri Vahid Shadravan Department of Chemical Engineering Shahid Bahonar University of Kerman Young Researchers Society Shahid Bahonar University of Kerman

A simplified kinetic model for the oxidative coupling of methane over a La0.6Sr0.4Co0.8Fe0.2O3-δ nanocatalyst is presented. The kinetic model was developed by experimental data in a catalytic micro-reactor covering a wide range of reaction conditions （0.04〈PO2〈0.15 atm, 0.2〈PCH4〈0.85 atm, 800〈T 〈900 °C）. Power law rate expressions were used for all reactions. The reaction scheme proposed in this work includes the most important reactions of oxidative coupling of methane and those involved in most of the available mechanisms in the literature. From the experimental data, kinetic parameters, i.e., pre-exponential factors, activation energies and power law exponents, were estimated. The compatibility of model results with experimental data was investigated and the accuracy of the model prediction was evaluated. Rates of methane consumption, C2＋ and COx formation, methane conversion, and C2＋ selectivity and yield were compared with experimental data using presented kinetics. The kinetic model was also compared with four previous kinetic models in terms of methane conversion.

关键词： nanocatalyst kinetic model oxidative coupling of methane

Multi Objective Load Shedding Framework

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Smart Grid and Renewable Energy 2015年第8期6卷 260-277页

作者： Atieh Delavari Milad Nemati mohammad H. moradi Power System Engineering HamedanIran Photovoltaic Systems Power Engineering HamedanIran Microgrids Control Power Engineering HamedanIran

In this paper, a multi-objective load shedding framework on the power system is presented. The frame work is useable in any kind of smart power systems;the word of smart here refers to the availability of data transmission infrastructure (like PLC or power line carrier) in the system, in order to carry the system data to the load shedding framework. This is an open framework that means it can optimize load shedding problem by considering unlimited number of objective functions, in other word, the number of objectives can be as much as the operator decides, finally in the end of frame work just one matrix breaker state is chosen in a way of having the most compatibility with the operator ideas which are determined by objectives importance percentage which are one input groups of the framework. A two-stage methodology is used for the optimal load shedding problem. In the first stage, Discrete Multi-objective Particle Swarm Optimization method is used to find a collection of the best states of load shedding (Pareto front). In the second stage, the fuzzy logic is used as a Pareto front inference engine. Fuzzy selection algorithm (FSA) is designed in a way that it can infer according to the operator’s opinion without the expert interference that means rule base is formed automatically by fuzzy algorithm. FSA is consisted of two parts. Membership functions and rules base are formed automatically in the first part, the former in accordance with the costs of Pareto front particles and the latter in correspondence with importance percentage of objectives which are entered to FSA by operator;in other word, decision matrix is formed automatically in the algorithm according to the cost of Pareto front particles and importance percentage of objectives. In the Second part, Mamdani inference engine scrutinizes the Pareto front particles by the use of formed membership functions and rules base to know if they are compatible to operator’s opinion or not. Getting this approach, cost

关键词： Objective Load Shedding Pareto Front Fuzzy

Quantitative and financial evaluation of non-timber forest products(case study:Zemkan basin forests,West of Iran)

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Journal of Forestry Research 2017年第2期28卷 371-379页

作者： Sohrab moradi Soleiman mohammadi Limaei Peter Lohmander Mehrdad Khanmohammadi Faculty of Agricultural Sciences Payame Noor UniversityTehranIran University of Guilan Sowmeh SaraIran Department of Forestry Faculty of Natural ResourcesUniversity of GuilanSowmeh SaraIran Department of Forest Economics Faculty of Forest SciencesSwedish University of Agricultural SciencesUmeaSweden Department of Environmental Sciences Faculty of Natural ResourcesUniversity of GuilanSowmeh SaraIran

Although Zagros forests in western Iran lack industrial timber value due to the severe climate and socioeconomics problems, non-timber products are of great value and importance due to their high economic potential and also their potential to improve the welfare of forestdwelling and forest-fringe villagers. This study was done in the forests of the Zemkan basin, an important part of central Zagros forests, Iran, to recognize the non-timber forest products（NTFPS）, investigate their potential economic value and role in people＇s livelihood. Data, collected using forest cruising, participatory observations, interviews with indigenous and local persons and experts, identified wild pistachio resin, wild pistachio fruit, oak fruit and oak syrup（Shokeh manna） among the non-timber products in this basin with total potential harvestable NTFPs of 77.16,771.602, 13248.68, and 1324.868 tons per year,respectively. The economic rent from NTFPs is 33 US$/ha/year and its total expected values with consideration of real interest rate when the exploiter invests the capital in the bank（6.4 %） and when money is borrowed from the bank to execute the incorporated projects（8.4 %） are $516/ha and $393/ha, respectively. Furthermore, families＇ economic share from potential profit of NTFPs is annually$601 per household. In addition wild pistachio resin has the highest share of the total potential profit of NTFPs and its equal to 51 % of the total of potential profit of ***, it is suggested that decisions be made to increase the infrastructure and strengthen the local selling market to enhance the cash income from NTFPs. Forest participatory management practices are suggested to organize and improve traditional use of the forests.

关键词： timber forests profit resin annually recognize fringe income household execute

Atlas of heating:Identifying regional climate-dependent heat demands in residential buildings of Iran

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Building Simulation 2021年第3期14卷 857-869页

作者： Pouria Orouji Ramin Hajian Mojgan moradi Saeed Mohaghegh Kamran Keynejad Mostafa Sefidgar Energy Department Asiawatt Engineering CompanyTehranIran Niroo Research Institute TehranIran Fouman Faculty of Engineering College of EngineeringUniversity of TehranGilanIran Pardis Islamic Azad University TehranIran

Due to different latitudes and variation of altitude in geographical areas in Iran,the climatic conditions of Iran are such that the variations of the heating degree-days(HDD)are in a broad range of 60 to 3000 for residential buildings in different climatic *** addition,in many cases,the building design and construction processes follow patterns which do not necessarily meet national energy requirements and *** on these two reasons,it is essential to identify the current status of energy consumption indicators in residential *** way,it gets more convenient to adopt new strategies to improve the current state of energy consumption of *** this study,heating energy consumption indices of residential buildings is *** the combination of the results of statistical data analysis,questionnaires,filled in for 500 buildings,and a reference building simulation in different climates of Iran,the heating atlas of residential buildings was *** to the results,the average heating energy index(HE1)of buildings in Iran can be less than 1 to more than 41.3(m^(3)(N.G)/(m^(2)-yr))depending on climatic conditions and building design and construction ***,in the coldest center of province,the average of this index is 26.3(m^(3)(N.G)/(m^(2)-yr))in the hottest one that is equal *** variations of the thermal base load(supply of hot water)varied from less than 13.12 to more than 378.84(m^(3)(N.G)/(person-yr)).In provincial capitals,the lowest thermal base load index(TBLI)of buildings is 24.78 and the highest is 226.49(m^(3)(N.G)/(person-yr)).In this paper,beside charts and tables,results of heating energy consumption indices are also presented in the form of graphical atlases,*** contour plots,to deliver a better picture of the whole country.

关键词： heating atlas reference building heating energy index thermal base load index residential building

Minimal Sufficiency in Rare Populations

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Journal of Mathematics and System Science 2012年第5期2卷 281-285页

作者： mohammad moradi Jennifer A. Brown Miriam Hodge Department of Science Razi University Kermanshah 67146 Iran Department of Mathematics and Statistics University of Canterbury Christchurch 8011 New Zealand

It is well understood that for conventional survey designs the set of unordered distinct units in a sample is a minimally sufficient statistic. This means that for inferential statistic of the sample, the value of the sampled units rather than the sample design is important. Sampling rare populations presents distinct challenges. Examples of rare populations are in biology with rare and endangered animals where there are only a few remaining individuals, or in social science, with the low incidence of people from an unusually high （or low） income group. Sampling rare populations tends to result in the case that many of the sample units do not contain information on the characteristic of interest （e.g., the rare animal, or people from the unusual income group）. For finite rare populations the set of unordered distinct rare-units in a sample is a minimally sufficient statistic. In an example case study of a rare buttercup, the properties of the minimal sufficient estimator are explored. We compare the efficiency of the estimator for the population total based on the minimally sufficient statistic, with the standard estimator for a range of sample sizes. The variance of the minimally sufficient estimator was always smaller than the variance of the sufficient estimator. For rare populations where non-rare units can be distinguished from rare units because they have the same fixed value, the minimal sufficient statistic is the rare units, if any, in the sample.

关键词： Rare population finite population sufficiency minimal sufficiency.

Efficient decomposition-based algorithm to solve long-term pipeline scheduling problem

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Petroleum Science 2019年第5期16卷 1159-1175页

作者： S.moradi S.A.Mir Hassani F.Hooshmand Department of Mathematics and Computer Science Amirkabir University of Technology(Tehran Polytechnic)TehranIran

This paper addresses the scheduling and inventory management of a straight pipeline system connecting a single refinery to multiple distribution *** increasing the number of batches and time periods,maintaining the model resolution by using linear programming-based methods and commercial solvers would be very *** this paper,we make an attempt to utilize the problem structure and develop a decomposition-based algorithm capable of finding near-optimal solutions for large instances in a reasonable *** algorithm starts with a relaxed version of the model and adds a family of cuts on the fly,so that a near-optimal solution is obtained within a few *** idea behind the cut generation is based on the knowledge of the underlying problem *** experiments on a real-world data case and some randomly generated instances confirm the efficiency of the proposed algorithm in terms of the solution quality and time.

关键词： Multi-product oil pipeline Batch sequencing Decomposition-based algorithm Combinatorial cuts Heuristic method

Design of Radial Basis Function Network Using Adaptive Particle Swarm Optimization and Orthogonal Least Squares

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Journal of Software Engineering and Applications 2010年第7期3卷 704-708页

作者： Majid moradi Zirkohi mohammad Mehdi Fateh Ali Akbarzade 不详

This paper presents a two-level learning method for designing an optimal Radial Basis Function Network (RBFN) using Adaptive Velocity Update Relaxation Particle Swarm Optimization algorithm (AVURPSO) and Orthogonal Least Squares algorithm (OLS) called as OLS-AVURPSO method. The novelty is to develop an AVURPSO algorithm to form the hybrid OLS-AVURPSO method for designing an optimal RBFN. The proposed method at the upper level finds the global optimum of the spread factor parameter using AVURPSO while at the lower level automatically constructs the RBFN using OLS algorithm. Simulation results confirm that the RBFN is superior to Multilayered Perceptron Network (MLPN) in terms of network size and computing time. To demonstrate the effectiveness of proposed OLS-AVURPSO in the design of RBFN, the Mackey-Glass Chaotic Time-Series as an example is modeled by both MLPN and RBFN.

关键词： Radial Basis Function Network Orthogonal Least Squares Algorithm Particle Swarm Optimization Mackey-Glass Chaotic Time-Series

Asphaltene precipitation modeling through ACE reaping of scaling equations

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Science China Chemistry 2014年第12期57卷 1774-1780页

作者： GHOLAMI Amin moradi Siyamak ASOODEH Mojtaba BAGHERIPOUR Parisa VAEZZADEH-ASADI Mohsen Faculty of Abadan Institute of Technology Petroleum University of Technology Department of Petroleum Engineering Kharg Branch Islamic Azad University

Precipitation and deposition of asphaltene have undesirable effects on the petroleum industry by increasing operational costs due to reduction of well productivity as well as catalyst *** we propose a reliable model for quantitative estimation of asphaltene *** equation is the most powerful and popular model for accurate prediction of asphaltene precipitated out of solution in crudes without regard to complex nature of *** employed a new mathematical-based approach known as alternating conditional expectation(ACE)technique for combining results of different scaling models in order to increase the accuracy of final *** of three well-known scaling equations,including Rassamdana(RE),Hu(HU),and Ashoori(AS),are input to ACE and the final output is produced through a nonlinear combination of scaling *** proposed methodology is capable of significantly increasing the precision of final estimation via a divide-andconquer principle in which ACE functions as the *** indicate the superiority of the proposed method compared with other individual scaling equation models.

关键词： asphaltene precipitation crude oil alternating conditional expectation scaling equation prediction