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Mining Science and Technology 2010年第5期20卷 691-695页

作者： SAFARI Mohsen ATAEI Mohammad khalokakaie reza KARAMOZIAN Mohammad Faculty of Mining Engineering Petroleum & GeophysicsShahrood University of Technology

Locating the mineral processing plant near a mine is the most important parameter that affects the whole *** factors,and their preferences,should be considered in this *** factors include economical,geological,technical,environmental and tectonic parameters.A multi-criteria decision making method is necessary to rank the *** this paper we describe how plant location is selected by using the Analytic Hierarchy Process(AHP).This method,with eight criteria,was used to select a location for the mineral processing plant at the Sangan iron ore mine(phase 1).Three alternatives for the processing plant were *** main criteria were distance from the mine,access to heavy machinery transport,the amount of excavation required for grading,bed mixture capacity,belt conveyor length,distance from the tailing dam,distance from the waste dumps and surface water diversion ***,the alternatives were ranked and the best location was proposed.

关键词： mineral processing multi-criteria decision making Sangan iron ore mine AHP

Reliability and maintainability analysis of electrical system of drum shearers

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Journal of Coal Science & Engineering(China) 2011年第2期17卷 192-197页

作者： SEYED Hadi Hoseinie MOHAMMAD Ataei reza khalokakaie UDAY Kumar Faculty of Mining Petroleum ＆ Geophysics Shahrood University of Technology Shahrood *** Iran Division of Operation and Maintenance Engineering Lulea University of Technology Lulea 97187 Sweden

The reliability and maintainability of electrical system of drum shearer at Parvade. 1 Coal Mine in central Iran was analyzed. The maintenance and failure data were collected during 19 months of shearer operation. According to trend and serial correlation tests, the data were independent and identically distributed （iid） and therefore the statistical techniques were used for modeling. The data analysis show that the time between failures （TBF） and time to repair （TTR） data obey the lognormal and Weibull 3 parameters distribution respectively. Reliability-based preventive maintenance time intervals for electrical system of the drum shearer were calculated with regard to reliability plot. The reliability-based maintenance intervals for 90%, 80%, 70% and 50% reliability level are respectively 9.91, 17.96, 27.56 and 56.1 h. Also the calculations show that time to repair （TTR） of this system varies in range 0.17-4 h with 1.002 h as mean time to repair （MTTR）. There is a 80% chance that the electrical system of shearer of Parvade. 1 mine repair will be accomplished within 1.45 h.

关键词： drum shearer electrical system reliabilitv maintenance

Prediction of cavity growth rate during underground coal gasification using multiple regression analysis

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International Journal of Coal Science & Technology 2015年第4期2卷 318-324页

作者： Mehdi Najafi Seyed Mohammad Esmaiel Jalali reza khalokakaie Farrokh Forouhandeh Department of Mining and Metallurgical Engineering YazdUniversity Safayieh P.O. Box 89195-741 Yazd Iran Faculty of Mining Engineering Petroleum and GeophysicsShahrood University Shahrud Iran Department of Mathematics Shahrood University ShahrudIran

During underground coal gasification （UCG）, whereby coal is converted to syngas in situ, a cavity is formed in the coal seam. The cavity growth rate （CGR） or the moving rate of the gasification face is affected by controllable （operation pressure, gasification time, geometry of UCG panel） and uncontrollable （coal seam properties） factors. The CGR is usually predicted by mathematical models and laboratory experiments, which are time consuming, cumbersome and expensive. In this paper, a new simple model for CGR is developed using non-linear regression analysis, based on data from 1 l UCG field trials. The empirical model compares satisfactorily with Perkins model and can reliably predict CGR.

关键词： Underground coal gasification (UCG) - Cavity growth rate . Multiple regression analysis ~ Empirical model

Serendipity in Recommender Systems:A Systematic Literature Review

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Journal of Computer Science & Technology 2021年第2期36卷 375-396页

作者： reza Jafari Ziarani reza Ravanmehr Department of Computer Engineering Central Tehran BranchIslamic Azad UniversityTehran ***Iran

A recommender system is employed to accurately recommend items,which are expected to attract the user's *** over-emphasis on the accuracy of the recommendations can cause information over-specialization and make recommendations boring and even *** and diversity are two partly useful solutions to these ***,novel and diverse recommendations cannot merely ensure that users are attracted since such recommendations may not be relevant to the user's ***,it is necessary to consider other criteria,such as unexpectedness and *** is a criterion for making appealing and useful *** usefulness of serendipitous recommendations is the main superiority of this criterion over novelty and *** bulk of studies of recommender systems have focused on serendipity in recent ***,a systematic literature review is conducted in this paper on previous studies of serendipity-oriented recommender ***,this paper focuses on the contextual convergence of serendipity definitions,datasets,serendipitous recommendation methods,and their evaluation ***,the trends and existing potentials of the serendipity-oriented recommender systems are discussed for future *** results of the systematic literature review present that the quality and the quantity of articles in the serendipity-oriented recommender systems are progressing.

关键词： systematic literature review recommender system serendipity evaluation metric evaluation method

Cooperative Neuro Adaptive Control of Leader Following Uncertain Multi-Agent Systems with Unknown Hysteresis and Dead-Zone

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Journal of Systems Science & Complexity 2020年第2期33卷 312-332页

作者： SHAHNAZI reza Department of Electrical Engineering Faculty of EngineeringUniversity of GuilanRasht ***Iran

In this paper,a cooperative adaptive control of leader-following uncertain nonlinear multiagent systems is *** communication network is weighted undirected graph with fixed *** uncertain nonlinear model for each agent is a higher-order integrator with unknown nonlinear functions,unknown disturbances and unknown input ***,the gains of input actuators are unknown nonlinear functions with unknown *** most common behaviors of input actuators in practical applications are hysteresis and *** this paper,backlash-like hysteresis and dead-zone are used to model the input *** universal approximation theorem proved for neural networks,the unknown nonlinear functions are *** unknown weights of neural networks are derived by proposing appropriate adaptive *** cope with modeling errors and disturbances an adaptive robust structure is *** Lyapunov synthesis approach not only all the adaptive laws are derived but also it is proved that the closed-loop network is cooperatively semi-globally uniformly ultimately bounded(CSUUB).In order to investigate the effectiveness of the proposed method,it is applied to agents modeled with highly nonlinear mathematical equations and inverted *** results demonstrate the effectiveness and applicability of the proposed method in dealing with both numerical and practical multi-agent systems.

关键词： Adaptive neural network backlash-like hysteresis dead-zone leader-following multi-agent systems weighted undirected graph

Exponential B-spline collocation method for numerical solution of the generalized regularized long wave equation

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Chinese Physics B 2015年第5期24卷 177-190页

作者： reza Mohammadi Department of Mathematics University of Neyshabur

The aim of the present paper is to present a numerical algorithm for the time-dependent generalized regularized long wave equation with boundary conditions. We semi-discretize the continuous problem by means of the Crank-Nicolson finite difference method in the temporal direction and exponential B-spline collocation method in the spatial direction. The method is shown to be unconditionally stable. It is shown that the method is convergent with an order of θ（k2 ＋ h2）. Our scheme leads to a tri-diagonal nonlinear system. This new method has lower computational cost in comparison to the Sinc-collocation method. Finally, numerical examples demonstrate the stability and accuracy of this method.

关键词： solitary waves GRLW equation exponential B-spline collocation

Enhanced empirical models for predicting the drift capacity of less ductile RC columns with flexural,shear,or axial failure modes

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1251-1270页

作者： Mohammad reza AZADI KAKAVAND reza ALLAHVIRDIZADEH Unit of Strength of Materials and Structural Analysis Institute of Basic Sciences in Engineering SciencesUniversity of InnsbruckInnsbruck 6020Austria ISISE Department of Civil EngineeringUniversity of MinhoGuimaraes 4800-058Portugal

Capacity of components subjected to earthquake actions is still a widely interesting research topic. Hence, developing precise tools for predicting drift capacities of reinforced concrete (RC) columns is of great interest. RC columns are not only frequently constructed, but also their composite behavior makes the capacity prediction a task faced with many uncertainties. In the current article, novel empirical approaches are presented for predicting flexural, shear and axial failure modes in RC columns. To this aim, an extensive experimental database was created by collecting outcomes of previously conducted experimental tests since 1964, which are available in the literature. It serves as the basis for deriving the equations for predicting the drift capacity of RC columns by different regression analyses (both linear with different orders and nonlinear). Furthermore, fragility curves are determined for comparing the obtained results with the experimental results and with previously proposed models, like the ones of ASCE/SEI41-13. It is demonstrated that the proposed equations predict drift capacities, which are in better agreement with experimental results than those computed by previously published models. In addition, the reliability of the proposed equations is higher from a probabilistic point of view.

关键词： flexural-shear-axial failure drift capacity reinforced concrete columns statistical analysis fragility curves

Power Quality Assessment of Voltage Positive Feedback Based Islanding Detection Algorithm

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Journal of Modern Power Systems and Clean Energy 2020年第4期8卷 787-795页

作者： reza Bakhshi-Jafarabadi reza Ghazi Javad Sadeh Electrical Engineering Department Faculty of EngineeringFerdowsi University of MashhadMashhadIran

Islanding refers to a condition where distributed generators(DGs)inject power solely to the local load after electrical separation from power *** islanding detection methods(IDMs)categorized into remote,active,and passive groups have been reported to detect this undesirable *** active techniques,a disturbance is injected into the DG’s controller to drift a local yardstick out of the permissible *** this disturbance leads to more effective detections even in well-balanced island,it raises the total harmonic distortion(THD)of the output current under the normal operation *** paper analyzes the power quality aspect of the modified sliding mode controller as a new active IDM for grid-connected photovoltaic system(GCPVS)with a string *** performance is compared with the voltage positive feedback(VPF)method,a well-known active *** evaluation is carried out for a 1 k Wp GCPVS in MATLAB/Simulink platform by measuring the output current harmonics and THD as well as the efficiency under various penetration and disturbance *** output results demonstrate that since the proposed disturbance changes the amplitude of the output current,it does not generate harmonics/***,it has a negligible adverse effect on power *** is finally concluded that the performance of the sliding mode-based IDM is reliable from the standpoints of islanding detection and power quality.

关键词： Islanding detection method(IDM) power quality sliding mode controller total harmonic distortion(THD) voltage positive feedback(VPF)

Casting fluidity,viscosity,microstructure and tensile properties of aluminum matrix composites with different Mg_(2)Si contents

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Rare Metals 2022年第8期41卷 2767-2776页

作者： reza Vatankhah Barenji Department of Industrial Engineering Hacettepe UniveristyBeytepe Campus06800AnkaraTurkey

The effect of Mg_(2)Si amount on the properties of Al-Mg_(2)Si as-cast composites was investigated in this *** with different amounts of Mg_(2)Si(15 wt%,20 wt%and 25 wt%)were fabricated,and the fluidity,viscosity,porosity formation and tensile properties were then *** addition,optical microscope and scanning electron microscope were used for micros tructural studies and *** results reveal that with the amount of Mg_(2)Si increasing,the morphology of the primary Mg_(2)Si becomes irregular,the size of primary Mg_(2)Si increases,fluidity decreases,viscosity increases,and porosity amount *** reason for the higher amounts of porosities is the lower fluidity and higher *** addition,Al-15%Mg_(2)Si shows better tensile properties and higher quality index compared to other ***,the fracture surface of the composite with lower Mg_(2)Si amount reveals more ductile mode than those with higher Mg_(2)Si amount.

关键词： Al-Mg_(2)Si Microstructure Fluidity Tensile behavior Porosity

Detection mechanism and classification of design principles of peroxidase mimic based colorimetric sensors: A brief overview

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1492-1503页

作者： Ali reza Hormozi Jangi Mohammad reza Hormozi Jangi Saeed reza Hormozi Jangi Department of Chemistry College of SciencesShiraz UniversityShiraz 71454Iran

Synthesis and characterization of enzyme mimics with characteristic stability and high catalytic efficiency is an interesting field for ***,with the development of nanoscience and introducing of Fe3O4 magnetic nanoparticles as peroxidase mimics in 2007,various nanomaterials such as noble metals,metal oxides,and carbon materials were introduced as enzyme mimics(nanozymes).Various nanomaterials exhibit peroxidaselike activity,hence,most of the nanozymes are peroxidase *** the nanozyme based sensors were previously classified,the classifications have been focused on the type of nanozyme ***,the nanozyme based sensors were classified as peroxidase,hydrolase,and urease mimic-based ***,heretofore,these sensors are not classified based on the detection mechanism and principles of system *** aim of this review is the focus on the peroxidase mimic based colorimetric sensors as the most common nanozyme-based sensors and their classification based on principles of sensor design and review of the detection mechanism of the current mimic peroxidase based ***,some current challenges and future developments in this field are discussed.

关键词： Peroxidase mimic Nanozyme Enzyme-peroxidase mimic hybrids HP sensing pH sensing Enzyme co-embedded nanomaterials