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Effect of Deep Cryogenic Heat Treatment on the Wear Behavior of Carburized DIN 1.7131 Grade Steel

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 348-353页

作者： kamran Amini AliReza Araghi Amin Akhbarizadeh Department of Materials Science Majlesi BranchIslamic Azad University Department of Materials Science and Engineering Shiraz BranchIslamic Azad University

The effects of the deep cryogenic heat treatment on the microstructural changes,wear resistance,and hardness of carburized DIN 1.7131 grade steel were *** show that cryogenic heat treatment reduced the retained austenite and increased the carbide *** addition,after the cryogenic heat treatment,carbide shows a more uniform distribution,as compared to the conventionally treated *** was also clarified that the hardness of the cryogenically treated samples was improved,but the relative improvement decreases with the distance as the surface *** has been shown that the wear resistance improves due to the cryogenic heat treatment,and the predominant wear mechanism is a combination of the adhesive and tribo-chemical wear.

关键词： DIN 1.7131 grade steel Carburized steel Hardness Deep cryogenic heat treatment Tribo-chemical wear

Diketene-based neat four-component synthesis of the dihydropyrimidinones and dihydropyridine backbones using silica sulfuric acid(SSA)

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Chinese Chemical Letters 2012年第8期23卷 930-932页

作者： Sadegh Rostamnia kamran Lamei Organic and Nano Group(ONG) Department of ChemistryFaculty of ScienceUniversity of MaraghehP.O.Box 55181-83111MaraghehIran

Heterocyclic skeleton building blocks to afford dihydropyrimidinones and dihydropyridines based on neat adducts of diketene, alcohols and aldehydes via silica sulfuric acid （SSA） catalyzed ring opening of diketene i... 详细信息

关键词： Diketene Dihydropyrimidinone Dihydropyridine Heterocyclic skeleton Silica sulfuric acid

A self-routing load balancing algorithm in parallel computing: comparison to the central algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第6期12卷 455-463页

作者： Razieh Sadat SADJADY kamran ZAMANIFAR Department of Computer Engineering Islamic Azad University

Load balancing is an important stage of a system using parallel computing where the aim is the balance of workload among all processors of the system. In this paper, we introduce a new load balancing algorithm with new capabilities for parallel systems, among which is the independence of a separate route-finder algorithm between the load receiver and sender nodes. In addition to simulation of the new algorithm, due to similarity in behavior to the proposed algorithm, the central algorithm is simulated. Simulation results show that, the system performance increases with the increase of the degree of neighborhood between the processors. These results also indicate the algorithm’s high compatibility with environment changes.

关键词： Parallel computing Load balancing Distributed system

Effect of deep cryogenic treatment on the formation of nano-sized carbides and the wear behavior of D2 tool steel

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 795-799页

作者： kamran Amini Amin Akhbarizadeh Sirus Javadpour Department of Materials Science and Engineering Majlesi Branch Islamic Azad University Isfahan 86315/111 Iran Department of Materials Science and Engineering School of Engineering Shiraz University Zand Ave. Shiraz *** Fars Iran

The effect of deep cryogenic treatment on the microstructure, hardness, and wear behavior of D2 tool steel was studied by scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, X-ray diffraction （XRD）, hardness test, pin-on-disk wear test, and the reciprocating pin-on-fiat wear test. The results show that deep cryogenic treatment eliminates retained austenite, makes a better carbide distribution, and increases the carbide content. Furthermore, some new nano-sized carbides form during the deep cryogenic treatment, thereby increasing the hardness and improving the wear behavior of the samples.

关键词： cryogenic treatment tool steel nano-sized carbides wear resistance hardness austenite

A two-dimensional limit equilibrium computer code for analysis of complex toppling slope failures

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第1期13卷 114-130页

作者： Akbar Ardestani Mehdi Amini kamran Esmaeili School of Mining Engineering College of EngineeringUniversity of TehranTehranIran Department of Civil and Mineral Engineering University of TorontoTorontoOntarioCanada

Evaluation of blocky or layered rock slopes against toppling failures has remained of great concern for engineers in various rock mechanics *** step-by-step analytical solutions have been developed for analyzing these types of slope ***,manual application of these analytical solutions for real case studies can be time-consuming,complicated,and in certain cases even *** study will first examine existing methods for toppling failure analyses that are reviewed,modified and generalized to consider the effects of a wide range of external and dead loads on slope ***,based on the generalized presented formulae,a Windows form computer code is programmed using Visual C#for analysis of common types of toppling *** parameters,including slope geometry,joint sets parameters,rock and soil properties,ground water level,dynamic loads,support anchor loads as well as magnitudes and forms of external forces,are first loaded into the *** input data are then saved and used to graphically draw the slope *** is followed by automatic identification of the toppling failure mode and a deterministic analysis of the slope stability against this failure *** results are presented using a graphical *** developed code allows probabilistic introduction of the input parameters via probability distribution functions(PDFs)and thus a probabilistic analysis of the toppling failure modes using Monte-Carlo simulation *** allows calculation of the probability of slope ***,several published case studies and typical examples are analyzed with the developed *** outcomes are compared with those of the main references to assess the performance and robustness of the developed computer *** comparisons demonstrate good agreement between the results.

关键词： Rock slope Toppling failures Analytical solution Windows form application Deterministic analysis Probabilistic analysis

Loss of offsite power (LOOP) accident analysis by integration of deterministic and probabilistic approaches in Bushehr-1 VVER-1000/V446 nuclear power plant

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Nuclear Science and Techniques 2022年第5期33卷 39-52页

作者： Mohsen Esfandiari Gholamreza Jahanfarnia kamran Sepanloo Ehsan Zarifi Department of Nuclear Engineering Science and Research BranchIslamic Azad UniversityTehranIran Reactor and Nuclear Safety School Nuclear Science and Technology Research Institute(NSTRI)TehranIran

The results of an accident analysis for the loss of offsite power(LOOP)scenario in a reference Bushehr-1 VVER-1000/V446 nuclear power plant(NPP)are presented in this *** study attempted to provide a better analysis of LOOP accident management by integrating deterministic and probabilistic *** RELAP5 code was used to investigate the occurrence of specific thermal–hydraulic *** probabilistic safety assessment of the LOOP accident is presented using the SAPHIRE *** accident data were extracted from the Bushehr NPP final safety analysis reports and probabilistic safety analysis reports.A deterministic approach was used to reduce the core damage frequency in the probabilistic analysis of LOOP *** probabilistic approach was used to better observe the philosophy of defense in depth and safety margins in the deterministic analysis of the LOOP *** results show that the integration of the two approaches in LOOP accident investigations improved accident control.

关键词： Loss of offsite power Deterministic Probabilistic Integration RELAP5 SAPHIRE

Polarimetric Synthetic Aperture Radar Image Classification by a Hybrid Method

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Tsinghua Science and Technology 2007年第1期12卷 97-104页

作者： kamran Ullah Khan 杨建 Department of Electronic Engineering Tsinghua University

Different methods proposed so far for accurate classification of land cover types in polarimetric synthetic aperture radar （SAR） image are data specific and no general method is available. A novel hybrid framework for this classification was developed in this work. A set of effective features derived from the coherence matrix of polarimetric SAR data was proposed. Constituents of the feature set are wavelet, texture, and nonlinear features. The proposed feature set has a strong discrimination power. A neural network was used as the classification engine in a unique way. By exploiting the speed of the conjugate gradient method and the convergence rate of the Levenberg-Marquardt method （near the optimal point）, an overall speed up of the classification procedure was achieved. Principal component analysis （PCA） was used to shrink the dimension of the feature vector without sacrificing much of the classification accuracy. The proposed approach is compared with the maximum likelihood estimator （MLE） based on the complex Wishart distribution and the results show the superiority of the proposed method, with the average classification accuracy by the proposed method （95.4%） higher than that of the MLE （93.77%）. Use of PCA to reduce the dimensionality of the feature vector helps reduce the memory requirements and computational cost, thereby enhancing the speed of the process.

关键词： undecimated discrete wavelet transform (UDWT) neural network principal component analysis (PCA)

Surface treatment of titanium dental implant with H2O2 solution

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1281-1286页

作者： Mohammad Khodaei kamran Amini Alireza Valanezhad Ikuya Watanabe Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan ***Iran Center for Advanced Engineering Research Majlesi BranchIslamic Azad UniversityIsfahan 196151194Iran Department of Dental and Biomedical Materials Science Graduate School of Biomedical SciencesNagasaki University1-7-1 SakamotoNagasaki 852-8588Japan

The surface treatment is important for titanium and its alloys as promising candidates for dental implantation due to their bioinert *** surface samples were modified using H2O2 solution at different times up to 72 h to boost their *** to the results of the field emission scanning electron microscopy test,some nanostructures are formed on the surface of treated titanium samples and increased in size by increasing the time of treatment up to 24 *** 24 h of application,the sharpness of nanostructures decreased and the micro-cracks and discontinuity in the coating surface *** results of the X-ray diffraction study and Raman spectroscopy revealed that anatase(TiO2)was formed on the surface of treated titanium *** peak intensity of Raman spectroscopy increased with an improvement in treatment time of up to 24 h and then decreased due to the discontinuity of the *** wettability and ability to form apatite were reached at 6 h of *** is clear that the treatment time has a significant effect on the surface treatment of titanium using the H2O2 solution.

关键词： titanium implant surface treatment hydrogen peroxide anatase dental implant

A Split-Step Predictor-Corrector Method for Space-Fractional Reaction-Diffusion Equations with Nonhomogeneous Boundary Conditions

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Communications on Applied Mathematics and Computation 2019年第4期1卷 525-544页

作者： kamran Kazmi Abdul Khaliq Department of Mathematics University of Wisconsin OshkoshOshkoshWI 54901USA Department of Mathematical Sciences and Center for Computational Sciences Middle Tennessee State UniversityMurfreesboroTN 37132USA

A split-step second-order predictor-corrector method for space-fractional reaction-diffusion equations with nonhomogeneous boundary conditions is presented and analyzed for the stability and *** matrix transfer technique is used for spatial discretization of the *** method is shown to be unconditionally stable and second-order *** experiments are performed to confirm the stability and secondorder convergence of the *** split-step predictor-corrector method is also compared with an IMEX predictor-corrector method which is found to incur oscillatory behavior for some time *** method is seen to produce reliable and oscillatioresults for any time step when implemented on numerical examples with nonsmooth initial *** also present a priori reliability constraint for the IMEX predictor-corrector method to avoid unwanted oscillations and show its validity numerically.

关键词： Fractional Laplacian Space-fractional reaction diffusion equations Non-homogeneous boundary conditions Matrix transfer technique Predictor-corrector method