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Reliability-based maintenance scheduling of hydraulic system of rotary drilling machines

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International Journal of Mining Science and Technology 2013年第5期23卷 771-775页

作者： mohammad javad rahimdel mohammad Ataei Reza Khalokakaei Seyed Hadi Hoseinie Faculty of Mining Engineering Sahand University of Technology Faculty of Mining Engineering Geophysics and PetroleumShahrood University of Technology Division of Operation and Maintenance Engineering Lulea University of Technology

Hydraulic system has a critical and important role in drilling *** failure in this system leads to problems in power system and machine *** the failure cannot be prevented entirely,it is important to minimize its *** is one of the most effcient and important method to study safe operation probability of hydraulic *** this research,the reliability of hydraulic system of four rotary drilling machines in Sarcheshmeh Copper Mine in Iran has been *** data analysis shows that the time between failures(TBF)of Machines A and C obey the Weibull(2P)and Weibull(3P)distribution,***,the TBF of Machines B and D obey the lognormal *** regard to reliability plots of hydraulic systems,preventive reliability-based maintenance time intervals for 80%reliability levels for machines in this system are 10 h.

关键词： Reliability Drilling Hydraulic Maintenance

Application of analytical hierarchy process to selection of primary crusher

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International Journal of Mining Science and Technology 2014年第4期24卷 519-523页

作者： rahimdel mohammad javad Ataei mohammad Faculty of Mining Engineering Sahand University of Technology Faculty of Mining Engineering Petroleum and Geophysics Shahrood University of Technology

Selection of crusher required a great deal of design based on the mining plan and operation input. Selection of the best primary crusher from all of available primary crushers is a Multi-Criterion Decision Making （MCDM） problem, in this paper, the Analytical Hierarchy Process （AHP） method was used to selection of the best primary crusher for Golegohar Iron Mine in Iran. For this reason, gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impactor, hammer mill and feeder breaker crushers were considered as alternatives and capacity, feed size, product size, rock compressive strength, abrasion index and mobility of crusher were considered as criteria. As a result of our study, the gyvratory crusher was offered as the best primary crusher for the studied mine.

关键词： MCDMA nalytical Hierarchy Process Primary crusher selection Golegohar Iron Mine

A Nonlinear Coordinated Approach to Enhance the Transient Stability of Wind Energy-Based Power Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1087-1097页

作者： mohammad javad Morshed the Department of Electrical and Computer Engineering University of Louisiana at LafayetteLafayetteLA 70504 USA

This paper proposes a novel framework that enables the simultaneous coordination of the controllers of doubly fed induction generators(DFIGs) and synchronous generators(SGs).The proposed coordination approach is based on the zero dynamics method aims at enhancing the transient stability of multi-machine power systems under a wide range of operating conditions. The proposed approach was implemented to the IEEE39-bus power systems. Transient stability margin measured in terms of critical clearing time along with eigenvalue analysis and time domain simulations were considered in the performance assessment. The obtained results were also compared to those achieved using a conventional power system stabilizer/power oscillation(PSS/POD) technique and the interconnection and damping assignment passivity-based controller(IDA-PBC). The performance analysis confirmed the ability of the proposed approach to enhance damping and improve system’s transient stability margin under a wide range of operating conditions.

关键词： Doubly fed induction generator(DFIG) excitation controller multi-machine power system synchronous generator(SG) transient stability zero dynamics

Application of Statistical Methods to Biomarkers for Geochemical Evaluation and Genetic Type Determination of Gas Condensates in the Persian Gulf and Coastal Fars,Southern Iran

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1246-1256页

作者： mohammad javad SEIDY mohammad Hossein SABERI Petroleum Engineering Department Semnan UniversitySemnanIran The New Technology Campus Petroleum Engineering DepartmentSemnan UniversitySemnanIran

In a comprehensive geochemical study,the genetic relationships among 14 samples of gas condensates from the Persian Gulf were investigated for the purpose of evaluating the respective source rocks in terms of both age and sedimentary *** analysis was used for categorization and determination of a certitude range to determine the genetic type of the condensate families in the studied *** samples were collected from Late Permian-Triassic reservoirs(Dalan and Kangan formations)located in 6 gasfields(gas condensate)hosting some of Iran’s most important gas/gas condensate *** by gas chromatography-mass spectrometry(GC-MS),a total of 16 biomarker parameters(10 maturity-related parameters and 6 sedimentary environment-related parameters)were used to evaluate the samples in terms of thermal maturity(and hence their positions in the maturity chart),the sedimentary environment of the source rock and the *** of Hierarchical Clustering Analysis(HCA)and Principal Component Analysis(PCA)to the collected data led to the categorization of the samples into three main genetic groups,Ⅰ-Ⅲ.GroupsⅠandⅢwere found to be located in the east and the west of the Persian Gulf,respectively,while GroupⅡwas developed between the two other groups.

关键词： gas condensate satistical methods genetic linkage thermal maturation Persian Gulf Coastal Fars

A Sliding Mode Approach to Enhance the Power Quality of Wind Turbines Under Unbalanced Voltage Conditions

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 566-574页

作者： mohammad javad Morshed Afef Fekih IEEE the Department of Electrical and Computer Engineering University of Louisiana at Lafayette

An integral terminal sliding mode-based control design is proposed in this paper to enhance the power quality of wind turbines under unbalanced voltage conditions. The design combines the robustness, fast response, and high quality transient characteristics of the integral terminal sliding mode control with the estimation properties of disturbance observers. The controller gains were auto-tuned using a fuzzy logic *** effectiveness of the proposed design was assessed under deep voltage sag conditions and parameter variations. Its dynamic response was also compared to that of a standard SMC *** performance analysis and simulation results confirmed the ability of the proposed approach to maintain the active power,currents, DC-link voltage and electromagnetic torque within their acceptable ranges even under the most severe unbalanced voltage conditions. It was also shown to be robust to uncertainties and parameter variations, while effectively mitigating chattering in comparison with the standard SMC.

关键词： Doubly fed induction generators(DFIG) fuzzy approach integral terminal sliding mode control(ITSMC) observer power quality voltage unbalances wind turbines

A novel hybrid algorithm based on a harmony search and artificial bee colony for solving a portfolio optimization problem using a mean-semi variance approach

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Journal of Central South University 2016年第1期23卷 181-188页

作者： Seyed mohammad Seyedhosseini mohammad javad Esfahani Mehdi Ghaffari Department of Industrial Engineering Iran University of Science and Technology Young Researchers and Elite Club Naragh BranchIslamic Azad University Department of Industrial Engineering Naragh BranchIslamic Azad University

Portfolio selection is one of the major capital allocation and budgeting issues in financial management, and a variety of models have been presented for optimal selection. Semi-variance is usually considered as a risk factor in drawing up an efficient frontier and the optimal portfolio. Since semi-variance offers a better estimation of the actual risk portfolio, it was used as a measure to approximate the risk of investment in this work. The optimal portfolio selection is one of the non-deterministic polynomial(NP)-hard problems that have not been presented in an exact algorithm, which can solve this problem in a polynomial time. Meta-heuristic algorithms are usually used to solve such problems. A novel hybrid harmony search and artificial bee colony algorithm and its application were introduced in order to draw efficient frontier portfolios. Computational results show that this algorithm is more successful than the harmony search method and genetic algorithm. In addition, it is more accurate in finding optimal solutions at all levels of risk and return.

关键词： portfolio optimizations mean-variance model mean semi-variance model harmony search and artificial bee colony efficient frontier

Micromechanical simulation and experimental investigation of aluminum-based nanocomposites

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Defence Technology（防务技术） 2021年第1期17卷 196-201页

作者： mohammad javad Ghasemi mohammad Silani Ali Maleki Mostafa Jamshidian Department of Mechanical Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

Ceramic reinforced metal matrix nanocomposites are widely used in aerospace and auto industries due to their enhanced mechanical and physical *** this research,we investigate the mechanical properties of aluminum/Nano-silica composites through experiments and ***/Nanosilica composite samples with different weight percentages of silica nanoparticles are prepared via powder *** this method,Nano-silica and aluminum powders are mixed and compressed in a mold,followed by sintering at high *** tensile testing of the nanocomposite samples shows that adding one percent of Nano-silica causes a considerable increase in mechanical properties of nanocomposite compared to pure aluminum.A computational micromechanical model,based on a representative volume element of aluminum/silica nanocomposite,is developed in a commercial finite element *** model employs an elastoplastic material model along with a ductile damage model for aluminum matrix and linear elastic model for nano-silica *** careful determination of model parameters from the experimental results of pure aluminum samples prepared by powder metallurgy,the proposed computational model has shown satisfactory agreement with *** validated computational model can be used to perform a parametric study to optimize the microstructure of nanocomposite for enhanced mechanical properties.

关键词： Aluminum/nano-silica composites Powder metallurgy Micromechanics

Stability of Nonlinear Systems Using Optimal Fuzzy Controllers and Its Simulation by Java Programming

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IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1519-1527页

作者： mohammad javad Mahmoodabadi Saideh Arabani Mostaghim Department of Mechanical Engineering Sirjan University of TechnologySirjan ***Iran Department of Computer Engineering Faculty of EngineeringUniversity of GuilanRasht 3756Iran

In this paper, at first, the single input rule modules(SIRMs) dynamically connected fuzzy inference model is used to stabilize a double inverted pendulum system. Then, a multiobjective particle swarm optimization(MOPSO) is implemented to optimize the fuzzy controller parameters in order to decrease the distance error of the cart and summation of the angle errors of the pendulums, simultaneously. The feasibility and efficiency of the proposed Pareto front is assessed in comparison with results reported in literature and obtained from other ***, the Java programming with applets is utilized to simulate the stability of the nonlinear system and explain the internetbased control.

关键词： Double inverted pendulum system fuzzy control Java programming multi-objective algorithm particle swarm optimization(PSO)

Strengthening of reinforced concrete beams using fiberreinforced cementitious matrix systems fabricated with custom-designed mortar and fabrics

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Frontiers of Structural and Civil Engineering 2023年第7期17卷 1100-1116页

作者： Ahmadreza RAMEZANI mohammad Reza ESFAHANI javad SABZI Faculty of Engineering Ferdowsi University of MashhadMashhadIran

The performance of a new fiber-reinforced cementitious matrix(FRCM)system developed using custom-designed mortar and fabrics is investigated in this *** behavior of this system is evaluated in terms of both the flexural and shear strengthening of reinforced concrete *** beams are designed to assess the effectiveness of the FRCM system in terms of flexural strengthening,and four specimens are designed to investigate their shear *** parameters investigated for flexural strengthening are the number of layers,span/depth ratio,and the strengthening *** previous studies,custom fabrics with similar axial stiffness are used in all strengthening methods in this *** the shear-strengthened specimens,the effects of the span/depth ratio and strengthening system type(fiberreinforced polymer(FRP)or FRCM)are *** proposed FRCM system exhibits desirable flexural and shear strengthening for enhancing the load capacity,provides sufficient bonding with the substrate,and prevents premature failure *** the similar axial stiffness of fabrics used in both FRCM and FRP systems and the higher load capacity of specimens strengthened by the former,cement-based mortar performs better than epoxy.

关键词： fiber-reinforced cementitious matrix flexural strengthening shear strengthening carbon fiber-reinforced polymer shear span