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Chinese Physics Letters 2006年第10期23卷 2670-2673页

作者： b.Kutlu m.Civi Department of Physics Gazi University 06500 Ankara Turkey

We study the order parameter probability distribution at the critical point for the three-dimensional spin-1/2 and spin-1 Ising models on the simple cubic lattice under periodic boundary conditions. The finite size scaling relation for the order parameter probability distribution is tested and verified numerically by microcanonical Creutz cellular automata simulations. The state critical exponent δ, which characterizes the far tail regime of the scaling order parameter probability distribution, is estimated for three-dimensional Ising models using the cellular automaton simulations at the critical temperature. The results are in good agreement with the monte Carlo calculations.

关键词： bLUmE-CAPEL mODEL mONTE-CARLO RENORmALIZATION-GROUP TRICRITICAL bEHAVIOR FREE-ENERGY mAGNETIZATION UNIVERSALITY SImULATION DImENSIONS EXPONENTS

Characterization of Austenite Dynamic Recrystallization under Different Z Parameters in a microalloyed Steel

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Journal of materials Science & Technology 2011年第4期27卷 359-363页

作者： m.Shaban b.Eghbali Department of materials Science and Engineering Sahand University of Technology

A low carbon Nb-Ti microalloyed steel was subjected to hot torsion testing over the temperature range 850-1100℃ and strain rates 0.01-1 s-1 to study the influence of deformation conditions on the dynamic recrystallization characteristics of austenite. The results show that dynamic recrystallization occurs more easily with the decrease of strain rate and the increase of deformation temperature. The complete dynamically recrystallized grain size as a function of Zener-Hollomon parameter was established. It was found that dynamically recrystallized grain sizes decrease with increasing strain rate and decreasing deformation temperature. The effect of microalloying elements on peak strain was investigated and the solute drag corrected peak strain was determined. Also, the dynamic recrystallization map of austenite was obtained by using recrystallization critical parameters.

关键词： Dynamic recrystallization microalloyed steel Grain size Hot torsion

PROXImAL POINT ALGORITHm FOR mINImIZATION OF DC FUNCTION

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Journal of Computational mathematics 2003年第4期21卷 451-462页

作者： Wen-yuSun Raimundo.J.b.Sampaio m.A.b.Candido SchoolofmathematicsandComputerScience NanjingNormalUniversityNanjing2100g7China ProgramadePos-GraduacaoemInformaticaAplicada PontificiaUniversidadeCatolicadoParana(PUCPR)CEP:80215-g01CuritibaPRBrazil ProgramadePos-GraduacaoemInformaticaAplicada PontificiaUniversidadeCatolicadoParana(PUCPR)CEP:80215-g01CuritibaPRBrazil

In this paper we present some algorithms for minimization of DC function (difference of two convex functions). They are descent methods of the proximal-type which use the convex properties of the two convex functions separately. We also consider an approximate proximal point algorithm. Some properties of the ε-subdifferential and the ε-directional derivative are discussed. The convergence properties of the algorithms are established in both exact and approximate forms. Finally, we give some applications to the concave programming and maximum eigenvalue problems.

关键词： Nonconvex optimization Nonsmooth optimization DC function Proximal point algorithm ε-subgradient.

Suitability of lost cores in rheocasting process

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中国有色金属学会会刊：英文版 2010年第S3期20卷 948-953页

作者： H.mICHELS m.büNCK A.büHRIG-POLACZEK Giesserei-Institut RWTH Aachen Intzestraeβ5Aachen 52072Germany

When treated in pressure die casting processes the semi-solid aluminum alloys demand resilient cores which can bear the stress occurring during filling and the final pressure *** design of permanent cores is highly restricted in order to maintain *** cores provide the possibility of complex,undercut geometrical shapes which is mandatory for a variety of casting ***,eligible materials which show appropriate resilience and proper decomposition properties at the same time,and in the upper echelon of cost-effectiveness,are seldom *** the semi-solid process suited between HPDC and GDC regarding the core stress,several common and economically efficient lost core systems could be used.A selection of potentially suitable materials was identified and *** range of testing comprises widespread sand core-systems(amin-pur-coldbox and CO2-water-glass) as well as materials less commonly used,namely salt,plastic and *** types of conditioning are applied to enhance the surface *** mechanical properties of the sand cores are enhanced by different heat treatment methods during *** cores are tested producing a research component cast on a HPDC machine with semi-solid A356 slurry fabricated in the cooling channel *** cast component was analyzed regarding shape stability,core removability and surface as well as the structure *** results show the importance of the surface conditioning for the sand-cores while salt and zinc produce good parts comparable to the reference steel core quality.

关键词： aluminum semi-solid rheocasting cooling channel lost core sand salt zinc plastic

Effects of an Electric Field on the Cylindrical Dust Acoustic Wave in magnetized Complex Plasmas

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Chinese Physics Letters 2012年第7期29卷 184-186页

作者： b.Farokhi m.Eghbali Department of Physics Faculty of ScienceArak UniversityArak 38156-8-8349Iran

Stability of a dust acoustic wave in cylindrical complex plasmas is *** of a static magnetic field (axial) and an electric field (radial) on the propagation of a low frequency wave are *** linear dispersion relations of rotational modes and breathing modes are *** a dusty plasma is confined in a finite region,the void behavior is observed at high speed *** structures of different-mode-number solutions are illustrated.

关键词： wave cylindrical illustrated

Influence of some rock strength properties on jaw crusher performance in granite quarry

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mining Science and Technology 2010年第2期20卷 204-208页

作者： OLALEYE b m Department of mining Engineering Federal University of Technology

The influence of rock strength properties on Jaw Crusher performance was carried out to determine the effect of rock strength on crushing time and grain size distribution of the *** was conducted on four different rock samples namely marble,dolomite,limestone and granite which were representatively selected from fragmented lumps in *** compressive strength and Point load tests were carried out on each rock sample as well as crushing time and size *** results of the strength parameters of each sample were correlated with the crushing time and the grain size distribution of the rock *** results of the strength tests show that granite has the highest mean value of 101.67 mPa for Unconfined Compressive Strength(UCS) test,6.43 mPa for Point Load test while dolomite has the least mean value of 30.56 mPa for UCS test and 0.95 mPa for Point Load *** to the International Society for Rock mechanic(ISRm) standard,the granite rock sample may be classified as having very high strength and dolomite rock sample,low ***,the granite rock has the highest crushing time(21.0 s) and dolomite rock has the least value(5.0 s).based on the results of the investigation,it was found out that there is a great influence of strength properties on crushing time of rock types.

关键词： rock strength jaw crusher crushing time grain size distribution efficiency

The Influence of the magnetic Field on the Electrical breakdown Phenomena

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Plasma Science and Technology 2007年第1期9卷 45-51页

作者： m.RADmILOVI -RADJENOVI b.RADJNOVI Institute of Physics P.O.Box 5711001 BelgradeSerbia Vin a Institute of Nuclear Sciences P.O.Box 522BelgradeSerbia

A simple phenomenological model and detailed simulation studies of the breakdown phenomena in argon and nitrogen under the simultaneous action of electric and magnetic fields are presented in this paper. Expressions for the breakdown voltage have been derived taking into account variations of both the ionization coefficient and the secondary electron yield in a magnetic field. Calculations were performed by using XOOPIC code, an Object Oriented Particle in Cell code, with both the original and the improved secondary emission model with inclusion of the influence of the magnetic field on the secondary electron production. The simulation results presented here clearly show that the inclusion of the dependence of the secondary electron yield on the magnetic field leads to better agreement with existing experimental results.

关键词： breakdown voltage ionization coefficient secondary electron emission simulation technique

Optimal Simultaneous Allocation of Electric Vehicle Charging Stations and Capacitors in Radial Distribution Network Considering Reliability

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Journal of modern Power Systems and Clean Energy 2024年第5期12卷 1584-1595页

作者： b.Vinod Kumar Aneesa Farhan m A the Department of Electrical and Electronic Engineering National Institute of Technology TiruchirappalliTamilnaduIndia

The popularity of electric vehicles(EVs)has sparked a greater awareness of carbon emissions and climate *** mobility expansion and EV adoption have led to an increased infrastructure for electric vehicle charging stations(EVCSs),impacting radial distribution networks(RDNs).To reduce the impact of voltage drop,the increased power loss(PL),lower system interruption costs,and proper allocation and positioning of the EVCSs and capacitors are *** paper focuses on the allocation of EVCS and capacitor installations in RDN by maximizing net present value(NPV),considering the reduction in energy losses and interruption *** a part of the analysis considering reliability,several compensation coefficients are used to evaluate failure rates and pinpoint those that will improve *** locate the best nodes for EVCSs and capacitors,the hybrid of grey wolf optimization(GWO)and particle swarm optimization(PSO)(HGWO_PSO)and the hybrid of PSO and Cuckoo search(CS)(HPSO_CS)algorithms are proposed,forming a combination of GWO,PSO,and CS *** impact of EVCSs on NPV is also investigated in this *** effectiveness of the proposed optimization algorithms is validated on an IEEE 33-bus RDN.

关键词： Electric vehicle charging station optimization radial distribution network vehicle-to-grid loss reduction reliability

Effects of calcination temperature and time on the Ca3Co4O9 purity when synthesized using starch-assisted sol-gel combustion method

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Journal of Advanced Ceramics 2020年第2期9卷 162-172页

作者： m.A.mOHAmmED m.b.UDAY S.IZmAN School of mechanical Engineering Faculty of EngineeringUniversiti Teknologi Malaysia(UTM)UTM Skudai 81310JohorMalaysia Centre for Advanced Composite materials(CACm) Institute for Vehicle Systems and EngineeringUniversiti Teknologi MalaysiaUTM Skudai 81310JohorMalaysia Department of materials Engineering College of EngineeringUniversity of BasrahBasrahIraq

Ca3Co4O9 is a p-type semiconducting material that is well-known for its thermoelectric(TE),magnetic,electronic,and electro-optic *** this study,sol–gel autoignition was used to prepare Ca3Co4O9 at different calcination temperatures(773,873,973,and 1073 K)and time(4,6,8,10,12,and 14 h)using starch as a *** phase and microstructure of the prepared Ca3Co4O9 powder were ***–differential thermal analysis(TGA)confirms that the final weight loss occurred at 1073 K to form Ca3Co4O9 stable *** variable-pressure scanning electron microscopy(VP-SEm)images show that the size of powder particles increases from 1.15 to 1.47μm as calcination time increases from 4 to 12 h,and the size remains almost constant thereafter.A similar pattern is also observed on the increment of the crystallite size and percentage of crystallinity with X-ray diffraction(XRD)*** highest crystallinity is found about 92.9%when the powder was calcinated at 1073 K for 12 and 14 h with 458 and 460Åcrystallite size,*** dispersive X-ray spectroscopy(EDS)analysis demonstrates that the calcinated powder has a high intensity of Ca,Co,and O with uniform ***-resolution transmission electron microscopy(HRTEm)images prove that there is no distinct lattice distortion defect on the crystal structure.

关键词： calcium cobalt oxide sol-gel starch combustion method crystallite size crystallinity

Laminar natural convection characteristics in an enclosure with heated hexagonal block for non-Newtonian power law fluids

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Chinese Journal of Chemical Engineering 2017年第5期25卷 555-571页

作者： Krunal m.Gangawane b.manikandan Department of Chemical Engineering College of Engineering StudiesUniversity of Petroleum and Energy Studies

This work illustrates the steady state, two dimensional natural convective flow and heat transfer features in square enclosure containing heated hexagonal block maintained either at constant wall temperature(CWT) or uniform heat flux(UHF) thermal conditions. Governing equations(mass, momentum and energy) are solved by using finite volume method(FVm) with 3rd order accurate QUICK discretization scheme and SImPLE algorithm for range of field pertinent parameters such as, Grashof number(10~3≤ Gr ≤ 10~6), Prandtl number(1 ≤ Pr ≤ 100) and power law index(0.5 ≤ n ≤ 1.5). The analysis of momentum and heat transfer characteristics are delineated by evolution of streamlines, isotherms, variation of average Nusselt number value and Colburn factor for natural convection(j_(nH)). A remarkable change is observed on fluid flow and thermal distribution pattern in cavity for both thermal conditions. Nusselt number shows linear variation with Grashof and Prandtl numbers; while rate of heat transfer by convection decreases for power law index value. Higher heat transfer rate can be achieved by using uniform heat flux condition. A Nusselt number correlation is developed for possible utilization in engineering/scientific design purpose.

关键词： Square cavity Heated block Grashof number Natural convection Power law index