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An incremental ant colony optimization based approach to task assignment to processors for multiprocessor scheduling

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Frontiers of Information Technology & Electronic Engineering 2017年第4期18卷 498-510页

作者： hamid reza BOVEIRI Sama Technical and Vocational Training College Islamic Azad University Shoushtar Branch Shoushtar Iran

Optimized task scheduling is one of the most important challenges to achieve high performance in multiprocessor environments such as parallel and distributed systems. Most introduced task-scheduling algorithms are based on the so-called list scheduling technique. The basic idea behind list scheduling is to prepare a sequence of nodes in the form of a list for scheduling by assigning them some priority measurements, and then repeatedly removing the node with the highest priority from the list and allocating it to the processor providing the earliest start time （EST）. Therefore, it can be inferred that the makespans obtained are dominated by two major factors：（1） which order of tasks should be selected （sequence subproblem）; （2） how the selected order should be assigned to the processors （assignment subproblem）. A number of good approaches for overcoming the task sequence dilemma have been proposed in the literature, while the task assignment problem has not been studied much. The results of this study prove that assigning tasks to the processors using the traditional EST method is not optimum; in addition, a novel approach based on the ant colony optimization algorithm is introduced, which can find far better solutions.

关键词： Ant colony optimization List scheduling Multiprocessor task graph scheduling Parallel and distributed systems

Characterization and corrosion behavior of Al-Co-rare earth(Ce-La)amorphous alloy

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Journal of Rare Earths 2023年第5期41卷 771-779,I0006页

作者： Seyed Ali Mousavi Sayed hamid Hashemi Ali Ashrafi reza Shoja Razavi Seyyed Mehdi Ghazi Mirsaeed Faculty of Materials and Manufacturing Technologies Malek Ashtar University of TechnologyTehran167885611Iran Department of Materials Engineering Malek Ashtar University of TechnologyIsfahanShahin-shahrIran Department of Materials Engineering Isfahan University of TechnologyIsfahan***Iran

A new Al-based amorphous alloy with excellent corrosion resistance and high thermal stability was produced in the Al-Co-RE(Ce-La)*** this regard,two different amorphous-nanocrystalline ribbons:Al_(87.6)-Co_(6.4)-Ce_(3.8-)La_(2.2)(M_(1))and Al_(82.3)-Co_(10.1)-Ce_(4.8)-La_(2.8)(M_(2))were prepared using melt *** results reveal the supercooled liquid region(ATx)of 218℃which shows that the M2alloy has higher thermal stability in comparison to the *** M2ribbons present the superior corrosion resistance because of the formation of amorphous *** icorr,Ecorr,Epit,and Epit-Ecorrvalues of fully amorphous Al-Co-Ce-La metallic ribbons have a better trend of anti-corrosion performance compared to other crystalline and amorphous aluminum alloys.

关键词： Amorphous alloys Melt-spinning Rare earth metal Corrosion behavior

Synthesis and Crystal Structure of N-(2-(1,3,4-oxadiazol-2-yl)phenyl)-2,3-dimethylaniline

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Chinese Journal of Structural Chemistry 2014年第3期33卷 407-414页

作者： Ali Souldozi Seyed hamid reza Shojaei Ali Ramazani Katarzyna ?lepokura Tadeusz Lis Department of Chemistry Urmia Branch Islamic Azad University Department of Physics Urmia Branch Islamic Azad University Department of Chemistry Zanjan Branch Islamic Azad University Faculty of Chemistry University of Wroc?aw 14 Joliot-Curie St. 50-383 Wroc?aw Poland

The title compound, N-（2-（1,3,4-oxadiazol-2-yl）phenyl）-2,3-dimethylaniline, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, ^1H- and ^13C-NMR spectroscopy, elemental analysis and mass spectrometry. These experimental studies were supported by theoretical optimizations.

关键词： single-crystal X-ray structure 1,3,4-oxadiazoles N-(2-(1,3,4-oxadiazol-2- yl)phenyl)-2,3-dimethylaniline (N-isocyanimino)triphenylphosphorane

Evaluation of charge storage ability of chrome doped Mn2O3 nanostructures derived by cathodic electrodeposition

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Progress in Natural Science:Materials International 2016年第6期26卷 523-527页

作者： hamideh Darjazi Saied Saeed Hosseiny Davarani hamid reza Moazami Taher Yousefi Farideh Tabatabaei Department of Materials Enginnering Naghshe Jahan Institute of Higher Education 2. Faculty of ChemistryShahid Beheshti University 3. School of Physics and acceleratorsNSTRI 4. NFCRSNuclear Science and Technology Research Institute

A facile synthetic route has been proposed to prepare cauliflower-like nanostructures of Cr doped MnO. The synthesis was carried out by constant current cathodic electrodeposition from Mnnitrate solutions containing minor amounts of dichromate. It was found that the presence of Cr mediates the formation of cathodic MnOwhich then reacts with the excess Mnspecies to form MnOnanostructures. X-Ray Diffraction(XRD),Scanning Electron Microscopy(SEM) and Differential Thermal Analysis(DTA) were used to characterize the nanostructures. The storage ability of the obtained nanostructures was investigated by cyclic voltammetry(CV)in 0.5 M NaSOsolution. The results indicated that the Cr doped manganese oxide material shows better performance than the non-doped one, and the charge capacity(SC) of doped manganese oxide(218 F/g) was higher than pure manganese oxide(208 F/g).

关键词： Electro synthesis Nanoparticles Energy storage Supercapacitor Manganese oxide

Synthesis and Crystal Structure of Methyl 2-(Diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate

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Chinese Journal of Structural Chemistry 2013年第1期32卷 82-88页

作者： Ali Souldozi Seyed hamid reza Shojaei Ali Ramazani Katarzyna lepokura Tadeusz Lis Department of Chemistry Urmia Branch Islamic Azad University P. O. Box 969 Urmia Iran Department of Physics Urmia Branch Islamic Azad University P. O. Box 969 Urmia Iran Department of Chemistry Zanjan Branch Islamic Azad University P. O. Box 49195-467 Zanjan Iran Faculty of Chemistry University of Wroclaw 14 Joliot-Curie St. 50-383 Wroclaw Poland

The title compound, methyl 2-（diphenylamino）-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573（3）, b = 19.533（7）, c = 9.876（3）, β = 92.35（4）°, V = 1845.2（10）3, T = 85（2） K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections with I2σ（I）.

关键词： single-crystal X-ray structure multi-component reaction methyl 2-(diphenylamino)-4-phenyl-1 3-thiazole-5-carboxylate benzoyl isothiocyanate diphenylamine dimethyl acetylenedicarboxylate

二氧化硅键合丙基哌-N-氨基磺酸作为可回收固体酸催化剂制备2-氨基-3-氰基-4-芳基-5,10-二氧代-5,10-二氢-4H-苯并[g]苯并吡喃和羟基取代的萘-1,4-二酮衍生物(英文)

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催化学报 2014年第2期35卷 242-246页

作者： Fahime Khorami hamid reza Shaterian Department of Chemistry Faculty of SciencesUniversity of Sistan and Baluchestan

An efficient method for the synthesis of 2-amino-3-cyano-4-aryl-5,10-dioxo-5,10-dihydro-4H- ben-zo[g]chromenes and hydroxy-substituted naphthalene-1,4-dione derivatives, using silica-bonded propylpiperazine-N-sulfamic acid as a solid acid, green, heterogeneous catalyst, under ambient and solvent-free conditions, is described. A simple procedure, high yields, short reaction time, safety, and reusability of the catalyst are advantages of these protocols.

关键词：固体酸催化剂氨基磺酸苯并吡喃酮衍生物二氧代二氧化硅丙基键合

Analysis of Spatial Autocorrelation Patterns of Heavy and Super-Heavy Rainfall in Iran

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Advances in Atmospheric Sciences 2017年第9期34卷 1069-1081页

作者： Iman ROUSTA Mehdi DOOSTKAMIAN Esmaeil HAGHIGHI hamid reza GHAFARIAN MALAMIRI Parvane YARAHMADI Department of Geography Yazd University Department of Geography Zanjan University Department of Geography Tabriz University Department of Geography Khwarizmi University

Rainfall is a highly variable climatic element, and rainfall-related changes occur in spatial and temporal dimensions within a regional climate. The purpose of this study is to investigate the spatial autocorrelation changes of Iran＇s heavy and super-heavy rainfall over the past 40 years. For this purpose, the daily rainfall data of 664 meteorological stations between 1971 and 2011 are used. To analyze the changes in rainfall within a decade, geostatistical techniques like spatial autocorrelation analysis of hot spots, based on the Getis-Ord Gi statistic, are employed. Furthermore, programming features in MATLAB, Surfer, and GIS are used. The results indicate that the Caspian coast, the northwest and west of the western foothills of the Zagros Mountains of Iran, the inner regions of Iran, and southern parts of Southeast and Northeast Iran, have the highest likelihood of heavy and super-heavy rainfall. The spatial pattern of heavy rainfall shows that, despite its oscillation in different periods, the maximum positive spatial autocorrelation pattern of heavy rainfall includes areas of the west, northwest and west coast of the Caspian Sea. On the other hand, a negative spatial autocorrelation pattern of heavy rainfall is observed in central Iran and parts of the east, particularly in Zabul. Finally, it is found that patterns of super-heavy rainfall are similar to those of heavy rainfall.

关键词： Iran heavy rainfall super-heavy rainfall spatial autocorrelation Gi index

Is multi-hazard mapping effective in assessing natural hazards and integrated watershed management?

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Geoscience Frontiers 2020年第4期11卷 1203-1217页

作者： hamid reza Pourghasemi Amiya Gayen Mohsen Edalat Mehrdad Zarafshar John P.Tiefenbacher Department of Natural Resources and Environmental Engineering College of AgricultureShiraz University71441-65186ShirazIran Department of Geography Ballygunge Science CollegeUniversity of CalcuttaKolkataWest Bengal700019India Crop Production and Plant Breeding Department School of AgricultureShiraz University71441-65186ShirazIran Natural Resources Department Fars Agricultural and Natural Resources Research and Education CenterAREEOShirazFarsIran Department of Geography Texas State UniversitySan MarcosTX78666USA

Natural hazards are often studied in ***,there is a great need to examine hazards holistically to better manage the complex of threats found in any *** regions of the world have complex hazard landscapes wherein risk from individual and/or multiple extreme events is *** parts of Iran experience a complex array of natural hazards-floods,earthquakes,landslides,forest fires,subsidence,and *** effectiveness of risk mitigation is in part a function of whether the complex of hazards can be collectively considered,visualized,and *** study develops and tests individual and collective multihazard risk maps for floods,landslides,and forest fires to visualize the spatial distribution of risk in Fars Province,southern *** do this,two well-known machine-learning algorithms-SVM and MARS-are used to predict the distribution of these *** floods,landslides,and forest fires were surveyed and *** locations of occurrence of these events(individually and collectively) were randomly separated into training(70%) and testing(30%) data *** conditioning factors(for floods,landslides,and forest fires) employed to model the risk distributions are aspect,elevation,drainage density,distance from faults,geology,LULC,profile curvature,annual mean rainfall,plan curvature,distance from man-made residential structures,distance from nearest river,distance from nearest road,slope gradient,soil types,mean annual temperature,and *** outputs of the two models were assessed using receiver-operating-characteristic(ROC) curves,true-skill statistics(TSS),and the correlation and deviance values from each models for each *** areas-under-the-curves(AUC) for the MARS model prediction were 76.0%,91.2%,and 90.1% for floods,landslides,and forest fires,***,the AUCs for the SVM model were 75.5%,89.0%,and 91.5%.The TSS reveals that the MARS model was better able to predict landslide risk,but was less able to

关键词： Multi-hazard risk mapping Considering flood Landside and forest fire jointly Machine-learning algorithms

Prediction of malaria cases in the southeastern Iran using climatic variables:An 18-year SARIMA time series analysis

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Asian Pacific Journal of Tropical Medicine 2021年第10期14卷 463-471页

作者： hamid reza Tohidinik Hossein Keshavarz Mehdi Mohebali Mandana Sanjar Gholamreza Hassanpour HIV/STI Surveillance Research Center and WHO Collaborating Center for HIV SurveillanceInstitute for Futures Studies in HealthKerman University of Medical SciencesKermanIran Center for Research of Endemic Parasites of Iran(CREPI) Tehran University of Medical SciencesTehranIran Department of Medical Parasitology&Mycology School of Public HealthTehran University of Medical SciencesTehranIran

Objective:To predict future trends in the incidence of malaria cases in the southeast of Iran as the most important area of malaria using Seasonal Autoregressive Integrated Moving Average(SARIMA)model,and to check the effect of meteorological variables on the disease ***:SARIMA method was applied to fit a model on malaria incidence from April 2001 to March 2018 in Sistan and Baluchistan province in southeastern *** variables such as temperature,rainfall,rainy days,humidity,sunny hours and wind speed were also included in the multivariable model as ***,the best fitted model was adopted to predict the number of malaria cases for the next 12 ***:The best-fitted univariate model for the prediction of malaria in the southeast of Iran was SARIMA(1,0,0)(1,1,1)12[Akaike Information Criterion(AIC)=307.4,validation root mean square error(RMSE)=0.43].The occurrence of malaria in a given month was mostly related to the number of cases occurring in the previous 1(p=1)and 12(P=1)*** inverse number of rainy days with 8-month lag(β=0.3292)and temperature with 3-month lag(β=-0.0026)were the best predictors that could improve the predictive performance of the univariate ***,SARIMA(1,0,0)(1,1,1)12 including mean temperature with a 3-month lag(validation RMSE=0.414)was selected as the final multivariable ***:The number of malaria cases in a given month can be predicted by the number of cases in the prior 1 and 12 *** number of rainy days with an 8-month lag and temperature with a 3-month lag can improve the predictive power of the model.

关键词： Malaria Time series SARIMA Forecasting Climate Iran