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

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

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Brain tissue segmentation based on spatial information fusion by Dempster-Shafer theory

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第7期13卷 520-533页

作者： Jamal GHASEMI Mohammad reza KARAMI MOLLAEI reza GHADERI ali HOJJATOLESLAMI Signal Processing Laboratory Faculty of Electrical and Computer EngineeringBabol University of TechnologyP.O.Box 484BabolIran School of Computing University of KentCanterbury CT2 7PDUK

As a result of noise and intensity non-uniformity,automatic segmentation of brain tissue in magnetic resonance imaging (MRI) is a challenging *** this study a novel brain MRI segmentation approach is presented which employs Dempster-Shafer theory (DST) to perform information *** the proposed method,fuzzy c-mean (FCM) is applied to separate features and then the outputs of FCM are interpreted as basic belief *** salient aspect of this paper is the interpretation of each FCM output as a belief structure with particular focal *** results of the proposed method are evaluated using Dice similarity and Accuracy *** and quantitative comparisons show that our method performs better and is more robust than the existing method.

关键词： Magnetic resonance imaging (MR/) Segmentation Fuzzy c-mean (FCM) Dempster-Shafer theory (DST)

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Relationship between fatigue life of asphalt concrete and polypropylene/polyester fibers using artificial neural network and genetic algorithm

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Journal of Central South University 2015年第5期22卷 1937-1946页

作者： Morteza Vadood Majid Safar Johari ali reza Rahai Textile Engineering Department Amirkabir University of Technology Civil and Environmental Engineering Department Amirkabir University of Technology

While various kinds of fibers are used to improve the hot mix asphalt(HMA) performance, a few works have been undertaken on the hybrid fiber-reinforced HMA. Therefore, the fatigue life of modified HMA samples using polypropylene and polyester fibers was evaluated and two models namely regression and artificial neural network(ANN) were used to predict the fatigue life based on the fibers parameters. As ANN contains many parameters such as the number of hidden layers which directly influence the prediction accuracy, genetic algorithm(GA) was used to solve optimization problem for ANN. Moreover, the trial and error method was used to optimize the GA parameters such as the population size. The comparison of the results obtained from regression and optimized ANN with GA shows that the two-hidden-layer ANN with two and five neurons in the first and second hidden layers, respectively, can predict the fatigue life of fiber-reinforced HMA with high accuracy(correlation coefficient of 0.96).

关键词： hot mix asphalt fatigue property reinforced fiber artificial neural network genetic algorithm

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Effects of preparation and operation conditions on precipitated iron nickel catalysts for Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第3期19卷 341-353页

作者： Mostafa Feyzi ali Akbar Mirzaei Hamid reza Bozorgzadeh Department of Chemistry Faculty of SciencesUniversity of Sistan & Baluchestan Research Institute of Petroleum Industry(RIPI) Gas Division

Iron nickel oxide catalysts were prepared using co-precipitation procedure and studied for the conversion of synthesis gas to light *** particular,the effects of a range of preparation variables such as Fe/Ni molar ratios of the precipitation solution,precipitate aging times,calcination conditions,different supports and loading of optimum support on the structure of catalysts and their catalytic performance for the tested reaction were *** was found that the catalyst containing 40%Fe/60%Ni/40wt%Al 2O3 ,which was aged for 180 min and calcined at 600 ℃ for 6 h was the optimum modified *** catalytic performance of optimal catalyst has been studied in different operation conditions such as reaction temperatures,H2 /CO molar feed ratios and reaction total *** of both precursors and calcined catalysts was carried out by powder X-ray diffraction（XRD）,scanning electron microscopy（SEM）,Brunauer-Emmett-Teller（BET） surface area measurements,thermal analysis methods such as thermal gravimetric analysis（TGA） and differential scanning calorimetry（DSC）.

关键词： iron nickel light olefins Fischer-Tropsch operation conditions

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Effective Controlled Islanding Method for Power Grids Solving a Sequence of Optimization Problems

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1004-1012页

作者： Mahdi Amini Haidar Samet ali reza Seifi Mahdi Davarpanah School of Electrical and Computer Engineering Shiraz UniversityShirazIran Department of Electrical Engineering Eindhoven University of TechnologyEindhoventhe Netherlands the Electrical and Computer Engineering School College of EngineeringUniversity of TehranTehranIran

Controlled islanding is an important approach to prevent instability in power *** this paper,a novel approach is proposed for power system separation,which consists of two steps:1)Finding multiple islanding scenarios;2)Choosing the best option to obtain the most desirable *** the first step,different islanding solutions are determined by a proposed hierarchical clustering *** this algorithm,which is based on a minimum active power flow disruption objective function,the generator coherency constraints are considered in the clustering *** the second step,the best separation scenario is chosen based on an arbitrary objective ***,in this paper,the amount of load shedding and the voltage profile deviation after separation are considered as the final criteria to select the best solution among available *** so doing,the degree of load importance is also taken into *** proposed two-step method is applied on an IEEE 9-bus test system and it is also evaluated on an IEEE 39-bus *** simulation results on the IEEE 39-bus grid and the comparative analysis with a state-of-the-art method confirm that the final islanding solution is more optimized based on the secondary criteria,which have not been addressed in the existing ***,the proposed method is computationally efficient and can be employed in real-scale power grids.

关键词： Graph theory hierarchical spectral clustering power system separation power system instability two-step approach.

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Statistical approach to determination of overhaul and maintenance cost of loading equipment in surface mining

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International Journal of Mining Science and Technology 2013年第3期23卷 441-446页

作者： Lashgari ali Sayadi Ahmad reza Department of Mining Engineering West Virginia University Department of Mining Faculty of Engineering Tarbiat Modares University

The purpose of this research was to develop a new approach in determination of overhaul and maintenance cost of loading equipment in surface mining. Two statistical models including univariate exponential regression (UER) and multivariate linear regression (MLR) were used in this study. Loading equipment parameters such as bucket capacity, machine weight, engine power, boom length, digging depth, and dumping height were considered as variables. The results obtained by models and mean absolute error rate indicate that these models can be applied as the useful tool in determination of overhaul and maintenance cost of loading equipment. The results of this study can be used by the decision-makers for the specific surface mining operations.

关键词： Overhaul and maintenance cost Loading equipment Surface mining Univariate exponential regression Multivariate linear regression Principal component analysis

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Application of 2,2'-dithiobis(4-methylthiazole) as sensing material for construction of Lu^(3+) PVC-membrane sensor

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Chinese Chemical Letters 2011年第8期22卷 977-980页

作者： Mohammad reza Abedi Hassan ali Zamani Department of Applied Chemistry Quchan BranchIslamic Azad UniversityQnchanIran

In this work a new Lu^（3＋） PVC-membrane sensor based on 2,2＇-dithiobis（4-methylthiazole）（TMT） has been *** sensor exhibits a Nernstian slope of 19.6±0.4 mV decade（？） in the concentration range of 1.0×10~6-1.0×10~2 mol L^1 and a detection limit of 6.8×10~7 mol L^*** could work well in the pH range of *** selectivity of the sensor against a lot of common alkaline,alkaline earth,transition,heavy metals and specially lanthanide ions was very good.

关键词： Ion-selective electrode Potentiometry Sensor PVC membrane

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Solvent-free preparation of arylaminotetrazole derivatives using aluminum(Ⅲ) hydrogensulfate as an effective catalyst

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Chinese Chemical Letters 2010年第8期21卷 892-896页

作者： Ferydoon Khamooshi ali reza Modarresi-Alam Deparment of Chemistry Faculty of ScienceUniversity of Sistan and Baluchestan

An efficient and simple method for the preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum（Ⅲ） hydrogensulfate（Al（HSO4）3） as an effective heterogeneous catalyst from secondary arylcyanamides. Generally,when the substitution in arylcyanamide is strongly electron-withdrawing the position of equilibrium would shift toward the isomer of 1-aryl-5-amino-1H-tetrazole（B） and as the electron-donating of substituent increased,the position of equilibrium is shifted toward the isomer of 5-arylamino-1H-tetrazole（A）.The present methodology offers several advantages,such as excellent yields,short reaction times,easy work-up and greener conditions.

关键词： 5-Arylamino-1H-tetrazole 1-Aryl-5-amino-1H-tetrazole Secondary arylcyanamide Aluminum(Ⅲ) hydrogensulfate(Al(HSO_4)_3) Heterogeneous catalyst Solvent-free Solid acid

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A fuzzy logic model to predict the out-of-seam dilution in longwall mining

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International Journal of Mining Science and Technology 2015年第1期25卷 91-98页

作者： ali Bahri Najafi Mohammad ali Ebrahimi Farsangi Golam reza Saeedi Mining Engineering Department Shahid Bahonar University of Kerman

The longwall mining method is often affected by the out-of-seam dilution （OSD）. Therefore, predicting and controlling of dilution are important factors for reducing mining costs. In this study, the fuzzy set theory and multiple regression models with parameters, including variation in seam thickness, dip of seam, seam thickness, depth of seam, and hydraulic radius as inputs to the models were applied to pre- dict the OSD in the longwall coal panels. Field data obtained from Kerman and Tabas coal mines, lran were used to develop and validate the models. Three indices including coefficient of determination （R2）, root mean square error （RMSE） and variance account for （VAF） were used to evaluate the perfor- mance of the models. With 10 randomly selected datasets, for the linear, polynomial, power, exponential, and fuzzy logic models, R2, RSME and VAF are equal to （0.85, 4.4, 84.4）, （0.61, 7.5, 59.6）, （0.84, 4.5, 72.7）, （0.80, 4.1, 79.6）, and （0.97, 2.1, 95.7）, respectively. The obtained results indicate that the fuzzy logic model predictor with R2 = 0.97, RMSE = 2.1, and VAF = 95.7 performs better than the other models.

关键词： Out-of-seam dilutionLongwall coal miningRegression modelingFuzzy set theoryKerman and Tabas coal mines

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Structural and Electronic Properties of Cyclic Peptide-gold Nanoparticle as a Drug Delivery System

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Chinese Journal of Structural Chemistry 2019年第4期38卷 566-580页

作者： KHOSHBAYAN Bahareh MORSali ali BOZORGMEHR Mohammad reza Department of Chemistry Mashhad Branch Islamic Azad University MashhadIran & Research Center for Animal Development Applied BiologyBranch Islamic Azad University

Using Au6 cluster and cyclooctaglycine model for gold nanoparticle(AuNP) and cyclic peptide(CP), twelve configurations for the functionalization of cyclic peptide-gold nanoparticle(CPAuNP) with gemcitabine(GEM) anticancer drug were investigated(CPAuNP/GEM1-12). Structural and electronic properties have been studied in gas phase and aqueous solution at M06-2 X/6-31 g(d,p). The energetic stability of CPAuNP/GEM1-12 was confirmed by the calculation of binding energies. Since the solubility of drug, CP and AuNP increases in CPAuNP/GEM1-12, cyclic peptide-gold nanoparticle could be used as an appropriate drug delivery system. Quantum molecular descriptors such as electrophilicity power and global hardness demonstrated that the reactivity of CP and GEM drug increases in CPAuNP/GEM1-12 configurations. The AIM analysis for CPAuNP/GEM1-12 indicated that the Au-L(L = H, O, F, C, N) interactions and intermolecular hydrogen bonds play important roles in this drug delivery system. All Au-Au and some of Au-L interactions are related to medium interactions. The most stable configurations are those in which GEM drug is parallel to the CPAuNP and interacts simultaneously with AuNP and CP.

关键词： gold nanoparticle gemcitabine cyclic peptide AIM analysis nanocarrier

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