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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

Two-dimensional Modeling of a Salt-gradient Solar Pond with Wall Shading Effect and Thermo-physical Properties Dependent on Temperature and Concentration

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Journal of Thermal Science 2011年第4期20卷 362-370页

作者： Mohsen Mazidi mohammad Hassan Shojaeefard mohammad Sh.Mazidi Hossein Shojaeefard Mechanical Engineering Department Islamic Azad University School of Mechanical Engineering Iran University of Science and Technology Management Business Administration Department Amirkabir University of Technology

In this paper,the behavior of a salt-gradient solar pond with the square cross-section has been studied experimentally and numerically.A small-scale solar pond were designed and built to provide quantitative data.A two-dimensional,transient heat and mass transfer model has been solved numerically by using finite-control-volume *** this study,all the thermo-physical properties are variable as the function of temperature and salt *** results as obtained for the experimental pond have been satisfactorily compared and validated against measured ***,the wall shading effect has been elaborated to improve the agreement between two sets of *** temperature of the storage zone is predicted well by the *** also can be observed that the initial concentration profile is preserved with *** stability of the pond in time has been investigated in order to distinguish the critical ***,the application of an energy analysis gives an efficiency of about 12%for the pond.

关键词： solar energy salt-gradient solar pond transient heat and mass transfer temperature and concentration profiles stability thermal efficiency

Modeling the effects of demand response on generation expansion planning in restructured power systems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第12期14卷 966-976页

作者： Mahdi SAMADI mohammad Hossein JAVIDI mohammad Sadegh GHAZIZADEH Department of Electrical Engineering Ferdowsi University of MashhadMashhadIran Department of Electrical Engineering Power and Water University of TechnologyTehranIran

Demand response is becoming a promising field of study in operation and planning of restructured power systems. More attention has recently been paid to demand response programs. Customers can contribute to the operation of power systems by deployment demand response. The growth of customers' participation in such programs may affect the planning of power systems. Therefore, it seems necessary to consider the effects of demand response in planning approaches. In this paper, the impact of demand responsiveness on decision making in generation expansion planning is modeled. Avoidance or deferment in installation of new generating units is comprehensively investigated and evaluated by introducing a new simple index. The effects of demand responsiveness are studied from the points of view of both customers and generation companies. The proposed model has been applied to a modified IEEE 30-bus system and the results of the study are discussed. Simulation results show that reducing just 3% of the customers' demand(due to price elasticity) may result in a benefit of about 10% for customers in the long term.

关键词： Demand response Generation expansion planning Responsive demand

Fabrication of phosphor bronze/Al two-phase material by recycling phosphor bronze chips using hot extrusion process and investigation of their microstructural and mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 809-817页

作者： Majid Hosseini mohammad Hossein Paydar Department of Materials Science and Engineering School of EngineeringShiraz UniversityShiraz 71964-84334Iran

Despite the existence of conventional methods for recycling chips,solid-state techniques have become popular,whereby waste metals are directly recycled into consolidated products with the desired shapes and *** investigated the feasibility of recycling phosphor bronze chips through a hot extrusion process using aluminum powder as a metal binder for the fabrication of a metal-fiber-reinforced aluminum matrix *** do so,mixtures containing 20 vol%–50 vol%of chips were prepared,cold-compacted,and *** quality of the consolidated samples was evaluated by determining the density of the fabricated composites and studying their *** addition,we performed tensile and hardness tests to evaluate the mechanical properties of the fabricated *** also analyzed the fracture surfaces of the samples to study the fracture mechanism as a function of the volume fraction of phosphor bronze chips in the fabricated *** results indicated that the most effective consolidation occurred in the sample containing 20 vol%of chips extruded at 465℃in which the chips serve as ideal fibers for improving the mechanical properties,especially the ultimate tensile strength,in comparison with those of Al matrixes that contain no chips but are produced under the same conditions.

关键词： recycling hot extrusion metal–metal composite phosphor bronze chips aluminum powder

An Alternative Technique for Compounding and Fabrication of Lithium Ion Conductive PVB Films with Enhanced Thermal Properties and Electrochromic Performance

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Chinese Journal of Polymer Science 2022年第10期40卷 1213-1222,I0009页

作者： mohammad Hossein Azarian Jatuphorn Wootthikanokkhan Materials Technology Program School of EnergyEnvironment and MaterialsKing Mongkut's University of Technology ThonburiBangkok 10140Thailand

This research concerns the development of lithium ions conductive electrolyte from poly(vinyl butyral)(PVB)resin for use as a special interlayer film in electrochromic *** obtain the final PVB film with high ionic conductivity and thermal stability,a masterbatch was firstly prepared by mixing of PVB resin with lithium salt(LiClO_(4))and additives in an aqueous ethanol *** this,the dried masterbatch were converted into final films by an extrusion *** this study,PVB film with the highest ionic conductivity value of 4.85×10^(-6) was obtained when the masterbatch was diluted with the neat PVB resin at the weight ratio of 2:1 in the extruder prior to *** results from cyclic voltammetry over 100 cycles,showed that performance of the electrochromic device(ITO/WO_(3)/PVB electrolyte/ITO)fabricated by using the above PVB film is stable and *** overall,this work demonstrates that ion conductive PVB films with compromised ionic conductivity and thermal stability can be prepared via an extrusion process without the need to modify chemical structure of *** was carried out through the masterbatch approach,by introducing (LiClO_(4)) salts into the plasticized PVB via a solution mixing process prior to converting it into a final film via the extrusion process.

关键词： Ionic conductivity Poly(vinyl butyral) Masterbatch mixing Solid polymer electrolyte Electrochromic glass Safety glass

An Effective Hybridization of Quantum-based Avian Navigation and Bonobo Optimizers to Solve Numerical and Mechanical Engineering Problems

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Journal of Bionic Engineering 2023年第3期20卷 1361-1385页

作者： mohammad H.Nadimi-Shahraki Faculty of Computer Engineering Najafabad BranchIslamic Azad UniversityNajafabad***Iran Big Data Research Center Najafabad BranchIslamic Azad UniversityNajafabad***Iran

Hybrid metaheuristic algorithms play a prominent role in improving algorithms' searchability by combining each algorithm's advantages and minimizing any substantial shortcomings. The Quantum-based Avian Navigation Optimizer Algorithm (QANA) is a recent metaheuristic algorithm inspired by the navigation behavior of migratory birds. Different experimental results show that QANA is a competitive and applicable algorithm in different optimization fields. However, it suffers from shortcomings such as low solution quality and premature convergence when tackling some complex problems. Therefore, instead of proposing a new algorithm to solve these weaknesses, we use the advantages of the bonobo optimizer to improve global search capability and mitigate premature convergence of the original QANA. The effectiveness of the proposed Hybrid Quantum-based Avian Navigation Optimizer Algorithm (HQANA) is assessed on 29 test functions of the CEC 2018 benchmark test suite with different dimensions, 30, 50, and 100. The results are then statistically investigated by the Friedman test and compared with the results of eight well-known optimization algorithms, including PSO, KH, GWO, WOA, CSA, HOA, BO, and QANA. Ultimately, five constrained engineering optimization problems from the latest test suite, CEC 2020 are used to assess the applicability of HQANA to solve complex real-world engineering optimization problems. The experimental and statistical findings prove that the proposed HQANA algorithm is superior to the comparative algorithms.

关键词： Optimization Metaheuristic algorithms Evolutionary algorithm Quantum-based avian navigation optimizer algorithm Engineering optimization problems,Bionic algorithm

Finding buckling points for nonlinear structures by dynamic relaxation scheme

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Frontiers of Structural and Civil Engineering 2020年第1期14卷 23-61页

作者： mohammad REZAIEE-PAJAND Hossein ESTIRI Civil Engineering Department Ferdowsi University of MashhadMashhad 91775-1111Iran

Dynamic Relaxation Method(DRM)is an explicit approach for solving the simultaneous systems of *** this tactic,the fictitious mass and damping are added to the static governing equations,and an artificial dynamic system is *** using DRM for nonlinear analysis,the structural static equilibrium path is *** outcome is extremely valuable,since it leads to the behavior of *** the finding related to the structural static path are the critical and buckling points for nonlinear *** this paper,a new way for calculating the load factor is proposed by setting the external work *** the dynamic relaxation scheme with external work technique has not been formulated so *** all incremental-iterative methods,the load factor increment sign should be determinated by extra *** sign leads to increase or decrease of the load *** is worth emphasizing that sign of the load factor increment changes at the load limit ***,the sign determinations are required in the common work control *** disadvantages are eliminated in the proposed *** fact,the suggested load factor depends only on the Dynamic Relaxation(DR)fictitious ***,all DR calculations are performed via vector ***,the load factor is calculated only by one formula,and it has the same relation in the all solution *** contrast to the arc length techniques,which requires the sign determined,the proposed scheme does not need any sign *** is shown that author’s technique is quicker than the other dynamic relaxation *** prove the capability and efficiency of the presented scheme,several numerical tests are *** results indicate that the suggested approach can trace the complex structural static paths,even in the snap-back and snap-through parts.

关键词： load factor external work dynamic relaxation static equilibrium path large displacement

Frost prediction based on a 3D CFD model of heat and mass transfer in a counter-cross-flow parallel-plate liquid-to-air membrane energy exchanger

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Building Simulation 2023年第11期16卷 2063-2076页

作者： mohammad Alipour Shotlou Nader Pourmahmoud Mechanical Engineering Department Urmia UniversityUrmiaIran

The frosting is a critical phenomenon in building systems because it decreases the performance of exchangers and damages *** this article,heat and mass transfer in a specified liquid-to-air membrane energy exchanger(LAMEE)and their effects on condensation and frost formation are simulated numerically using the 3D computational fluid dynamics(CFD)*** CFD model has been validated with experimental results for different design parameters,and the agreement is within±2%.The developed CFD model provides the distribution of temperature and humidity ratio and MgCh concentration along the *** the present study,effects of exchanger structure on producing viscosity and heat and mass transfer are *** selected LAMEE is a counter cross structure,therefore vortices appear in the inlet and outlet solution channel,and their influence can be seen on heat transfer in these *** addition,the diffusion of heat and mass transfer are studied on distributions of temperature and humidity *** show that the permeable membrane and moisture transfer make more regular temperature distribution along airflow direction in energy *** study provides an extended vision of heat and mass transfer.A 3-dimensional CFD model is developed to predict frost formation based on obtained temperature and humidity *** CFD model is validated with an experimental study by calculating the frost *** developed model distinguishes condensed and frosted areas,and a new parameter is defined for this purpose namely as the frosted humidity *** show that frost and condensation distributions depend significantly on temperature and humidity ratio *** temperature and humidity ratio to avoid air vapor to reach to saturation conditions is the better way to combat frosting.

关键词： frost CFD simulation moisture transfer membrane HVAC LAMEE

Application of reliability-centered maintenance for productivity improvement of open pit mining equipment:Case study of Sungun Copper Mine

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Journal of Central South University 2014年第6期21卷 2372-2382页

作者： Amin Moniri Morad mohammad Pourgol-mohammad Javad Sattarvand Department of Mining Engineering Sahand University of Technology Department of Mechanical Engineering Sahand University of Technology

Equipment plays an important role in open pit mining industry and its cost competence at efficient operation and maintenance techniques centered on reliability can lead to significant cost *** application of optimal maintenance process was investigated for minimizing the equipment breakdowns and downtimes in Sungun Copper *** results in the improved efficiency and productivity of the equipment and lowered expenses as well as the increased profit *** field operating data of 10 trucks are used to estimate the failure and maintenance profile for each component,and modeling and simulation are accomplished by using reliability block diagram *** analysis was then conducted to select proper probabilistic model for maintenance *** reliability of the system was evaluated and importance of each component was computed by weighted importance measure *** analysis led to identify the items with critical impact on availability of overall equipment in order to prioritize improvement ***,the availability of trucks was evaluated using Monte Carlo simulation and it is revealed that the uptime of the trucks is around 11000 h at 12000 operation ***,uncertainty analysis was performed to account for the uncertainty sources in data and models.

关键词： operating costs maintenance mining dump truck reliability availability uncertainty

A review of the efficacy of traditional Iranian medicine forinflammatory bowel disease

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World Journal of Gastroenterology 2010年第36期16卷 4504-4514页

作者： Roja Rahimi mohammad Abdollahi mohammad Reza Shams-Ardekani Faculty of Traditional Medicine Tehran University of Medical SciencesTehran ***Iran Faculty of Pharmacy Pharmaceutical Sciences Research CenterEndocrinology and Metabolism Research InstituteTehran University of Medical SciencesTehran ***Iran

The etiology of inflammatory bowel disease(IBD) is not yet known,but many factors such as defects in the immune system,oxidative stress,microbial content in the gastrointestinal tract,nuclear factor(NF)-κB,nitric oxide(NO),cyclooxygenase-2(Cox-2),and leukotriene B4(LB4) are thought to play a role in its *** traditional Iranian medicine(TIM),several medicinal plants are thought to be effective for the treatment of *** this study,information on all of these remedies were derived from all available old sources such as documents or notes and books and were added to the information derived from modern medical databases covering all in vitro,in vivo and clinical *** some of these plants,only one or two mechanisms of action have been found such as in Cassia fistula,Lepidium sativum,and Bunium ***,for some plants various mechanisms of action are *** example,Commiphora mukul is effective in IBD due to its immunomodulatory,antioxidant,and antibacterial properties and it decreases NF-κB,NO and *** herb,Plantago ovata,has immunomodulatory,antioxidant,anti-inflammatory and wound healing activities and decreases NO and *** the mechanisms of action of these plants,the combination of some of them may be useful because of their many mechanisms of action such as Pistacia lentiscus,Bunium persicum,Solanum nigrum,Plantago ovata,Boswellia,Solanum nigrum,Plantago ovata and Commiphora *** some of the herbal products used in TIM such as oleogum resin from Commiphora myrrha,seeds of Ocimum basilicum,seeds of Linum usitatissimum,gum resin of Dracaena cinnabari,seeds of Plantago major,seeds of Lallementia royleana,and seeds of Allium porrum,there is no or not enough studies to confirm their benefits in *** is suggested that an evaluation of the effects of these plants on different aspects of IBD should be performed.

关键词： Herbal medicine Inflammatory bowel disease Medicinal plants Traditional Iranian medicine