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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 976-988页

作者： Ashkan TASHK mohammad Sadegh HELFROUSH mohammad javad dehghani Faculty of Electrical Engineering Shiraz University of Technology Shiraz Iran

We introduce a novel coarse ridge orientation smoothing algorithm based on orthogonal polynomials, which can be used to estimate the orientation field (OF) for fingerprint areas of no ridge information. This method does not need any base information of singular points (SPs). The algorithm uses a consecutive application of filtering-and model-based orientation smoothing methods. A Gaussian filter has been employed for the former. The latter conditionally employs one of the orthogonal polynomials such as Legendre and Chebyshev type I or II, based on the results obtained at the filtering-based stage. To evaluate our proposed method, a variety of exclusive fingerprint classification and minutiae-based matching experiments have been conducted on the fingerprint images of FVC2000 DB2, FVC2004 DB3 and DB4 databases. Results showed that our proposed method has achieved higher SP detection, classification, and verification performance as compared to competing methods.

关键词： Coherence Consistency Fingerprint orientation Legendre/Chebyshev orthogonal polynomials

Waveform Design for Cognitive Radar with Deterministic Extended Targets in the Presence of Clutter

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International Journal of Communications, Network and System Sciences 2016年第6期9卷 250-268页

作者： Vahid Karimi Reza Mohseni Yaser Norouzi mohammad javad dehghani Department of Electrical Engineering Shiraz University of Technology Shiraz Iran Department of Electrical Engineering Amirkabir University of Technology Tehran Iran

Adjusting radar transmitted waveform to its environment is one of the most important roles in cognitive radar;having the capability of updating transmitted waveforms in different applications is a key point. It has been shown in many studies that if the waveform is designed according to the target and clutter characteristics, the detection performance will improve significantly. The uncertainty of the target radar signatures decreases via maximizing MI and the probability of extended target detection is increases via maximizing SNR. In this paper, a waveform design approach based on maximizing both SNR and MI and with regard to target and clutter shape is presented. The detection performance for proposed waveform is compared with previous proposed waveforms. The present paper compares different scenarios of target and clutter and using the probability of detection as a cost function to investigate the advantages and disadvantages of each waveform in different scenarios which are mainly discussed in this text. The desired waveform for cognitive radar is selected based on simultaneously making compromises between SNR and MI, which plays an important role in cognitive radar systems and based on the assumption addressed in the text, the best waveform transmitted into the environment.

关键词： Signal to Noise Ratio Mutual Information Cognitive Radar Deterministic Extended Target Clutter

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

Migration Algorithm:A New Human-BasedMetaheuristic Approach for Solving Optimization Problems

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 1695-1730页

作者： Pavel Trojovsky mohammad dehghani Department of Mathematics Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic

This paper introduces a newmetaheuristic algorithmcalledMigration Algorithm(MA),which is helpful in solving optimization *** fundamental inspiration of MA is the process of human migration,which aims to improve job,educational,economic,and living conditions,and so *** of the proposed MAis presented in two phases to empower the proposed approach in exploration and exploitation during the search *** the exploration phase,the algorithm population is updated based on the simulation of choosing the migration destination among the available *** the exploitation phase,the algorithm population is updated based on the efforts of individuals in the migration destination to adapt to the new environment and improve their ***’s performance is evaluated on fifty-two standard benchmark functions consisting of unimodal and multimodal types and the CEC 2017 test *** addition,MA’s results are compared with the performance of twelve well-known metaheuristic *** optimization results show the proposed MA approach’s high ability to balance exploration and exploitation to achieve suitable solutions for optimization *** analysis and comparison of the simulation results show that MA has provided superior performance against competitor algorithms in most benchmark ***,the implementation of MA on four engineering design problems indicates the effective capability of the proposed approach in handling optimization tasks in real-world applications.

关键词： Optimization metaheuristic migration human-based algorithm exploration exploitation

Fuzzy TOPSIS method to primary crusher selection for Golegohar Iron Mine(Iran)

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Journal of Central South University 2014年第11期21卷 4352-4359页

作者： mohammad javad Rahimdel mohammad Karamoozian Department of Mining Engineering Sahand University of TechnologyTabriz 51335-1996 Iran Faculty of Mining Engineering Petroleum and Geophysics Shahrood University of TechnologyShahrood 361999 5161 Iran

Selection of the crusher required a great deal of design regarding to the mine planning. Selection of suitable primary crusher from all of available primary crushers is a multi-criterion decision making(MCDM) problem. The present work explores the use of technique for order performance by similarity to ideal solution(TOPSIS) with fuzzy set theory to select best primary crusher for Golegohar Iron Mine in Iran. Gyratory, double toggle jaw, single toggle jaw, high speed roll crusher, low speed sizer, impact crusher, hammer mill and feeder breaker crushers have been considered as alternatives. Also, the capacity, feed size, product size, rock compressive strength, abrasion index and application of primary crusher for mobile plants were considered as criteria for solution of this MCDM problem. To determine the order of the alternatives, closeness coefficient is defined by calculating the distances to the fuzzy positive ideal solution(FPIS) and fuzzy negative ideal solution(FNIS). Results of our work based on fuzzy TOPSIS method show that the gyratory is the best primary crusher for the studied mine.

关键词： primary crusher multi-criterion decision making(MCDM) technique for order performance by similarity to ideal solution fuzzy set theory Golegohar Iron Mine gyratory crusher

Graphene oxide based carbon composite as adsorbent for Hg removal:Preparation, characterization, kinetics and isotherm studies

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1170-1175页

作者： Tayebeh Esfandiyari Navid Nasirizadeh mohammad dehghani mohammad Hassan Ehrampoosh Department of Environmental Health Engineering Shaheed Sadoughi University of Medical Sciences Young Researchers and Elite Club Yazd Branch Islamic Azad University

The presence of Hg in the aqueous media is known to cause severe health issues in both humans and *** technologies and especially adsorbents have been applied for its removal. In this study, a graphene oxide–carbon composite(GO–CC) as a new adsorbent was prepared by sol gel procedure and characterized using field emission scanning electron microscopy, BET and EDX. The effects of different variables including solution p H, contact time, adsorbent dose and GO ratio in adsorbent matrix on the removal capacity of Hg were studied. The isotherm data correlated well with the Langmuir isotherm model. Further analysis recommended that the Hg^(2+) adsorption process is governed by the intra-particle and external mass transfer, in which the film diffusion was the rate restrictive step. The presented composite has maximum absorption capacity, q_(max) of 68.8 mg·g^(-1), which is comparable with carbon based adsorbent reported in the previous publications.

关键词： Adsorbent Mercury removal Sol gel Carbon composite

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