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Frontiers in Energy 2015年第1期9卷 7-21页

作者： Y. K. BhATEShVAR h. d. MAThUR h. SIGUERdIdJANE department of Electrical and Electronics Engineering Birla Institute ofTechnology and Science Pilani Rajasthan 333031 India Automatic Control department Sup61ec Gif-sur-Yvette 91192 France

Among the available options for renewable energy integration in existing power system, wind power is being considered as one of the suited options for future electrical power generation. The major constraint of wind power generating system （WPGS） is that it does not provide inertial support because of power electronic converters between the grid and the WPGS to facilitate frequency stabilization. The proposed control strategy suggests a substantial contribution to system inertia in terms of short-term active power support in a two area restructured power system. The control scheme uses fuzzy logic based design and takes frequency deviation as input to provide quick active power support, which balances the drop in frequency and tie-line power during transient conditions. This paper presents a comprehensive study of the wind power impact with increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for the same power system model with the proposed control scheme. Simula- tion results advocates the justification of control scheme over other schemes.

关键词： two area power system automatic generationcontrol wind power generating system (WPGS) deregu-lated environment fuzzy logic controller (FLC)

Numerical Simulation of duct Flow with Fog droplets

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Journal of Thermal Science 2010年第6期19卷 533-539页

作者： Abhilash Suryan J. K. Lee d. S. Kim h. d. Kim department of Mechanical Engineering Andong National University FMTRC Daejoo Machinery Co.

Evaporative cooling is a widely used air cooling technique. In this method, evaporation of a liquid in the surrounding air cools the air in contact with it. In the current investigation, numerical simulations are carded out to visualize the evaporation and dynamics of tiny water droplets of different diameters in a long air duct. The effect of initial droplet size on the temperature and relative humidity distribution of the air stream in the duct is investigated. Three different initial conditions of air are considered to verify the influence of ambient conditions. droplet spray patterns are also analyzed to identify the suitable locations for the spray nozzles within the duct. The resuits obtained are displayed in a series of plots to provide a clear understanding of the evaporative cooling process as well as the droplet dynamics within the ducts.

关键词： Evaporative cooling Fog droplet Two-phase flow Relative humidity

Stereotactic radiosurgery for haemorrhagic cerebral cavernous malformation:a multi-institutional,retrospective study

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Stroke & Vascular Neurology 2024年第3期9卷 221-229,I0130,I0131页

作者： Chloe dumot Georgios Mantziaris Sam dayawansa Zhiyuan Xu Stylianos Pikis Selcuk Peker Yavuz Samanci Gokce d Ardor Ahmed M Nabeel Wael A Reda Sameh R Tawadros Khaled Abdelkarim Amr M N El-Shehaby Reem M Emad Eldin Ahmed h Elazzazi Nuria Martínez Moreno Roberto MartínezÁlvarez Roman Liscak Jaromir May david Mathieu Jean-Nicolas Tourigny Manjul Tripathi Akshay Rajput Narendra Kumar Rupinder Kaur Piero Picozzi Andrea Franzini herwin Speckter Wenceslao hernandez Anderson Brito Ronald E warnick Juan Alzate douglas Kondziolka Greg N Bowden Samir Patel Jason Sheehan department of Neurological Surgery Hospices Civils de LyonLyonFrance department of Neurological Surgery University of VirginiaCharlottesvilleVirginiaUSA department of Neurosurgery Koc University School of MedicineIstanbulTurkey Gamma-knife Center Nasser institute HospitalCairoEgypt Neurosurgery department Benha UniversityBenhaEgypt departments of Neurosurgery Ain Shams UniversityCairoEgypt department of Clinical Oncology Ain Shams UniversityCairoEgypt department of Radiation Oncology National Cancer InstituteCairo UniversityGizaEgypt Faculty of Medicine Extended Modular ProgramAin Shams UniversityCairoEgypt department of Radiosurgery Rúber Internacional HospitalMadridSpain department of Stereotactic and Radiation Neurosurgery Na Homolce HospitalPragueCzech Republic Neurosurgery Centre de recherche du CHUSUniversitéde SherbrookeSherbrookeQuebecCanada Neurosurgery PGIMERChandigarhChandigarhIndia Radiation Therapy PGIMERChandigarhChandigarhIndia Neurosurgery IRCCS Istituto Clinico HumanitasRozzanoMilanItaly dominican Gamma Knife Center and Radiology department CEDIMATSanto DomingoDominican Republic Gamma Knife Center Mayfield ClinicThe Jewish Hospital-Mercy HealthCincinnatiOhioUSA Neurosurgery NYU Langone HealthNew YorkNew YorkUSA Neurosurgery University of AlbertaEdmontonAlbertaCanada division of Radiation Oncology Department of OncologyUniversity of AlbertaEdmontonAlbertaCanada

Background Cerebral cavernous malformations(CCMs)frequently manifest with *** radiosurgery(SRS)has been employed for CCM not suitable for *** effect on reducing haemorrhage risk is still *** aim of this study was to expand on the safety and efficacy of SRS for haemorrhagic *** This retrospective multicentric study included CCM with at least one haemorrhage treated with single-session *** annual haemorrhagic rate(AhR)was calculated before and after *** event analysis and Cox regression were used to evaluate factors associated with *** radiation effects(AREs)and occurrence of new neurological deficits were *** The study included 381 patients (median age:37.5 years(Q1–Q3:25.8–51.9))with 414 *** AhR from diagnosis to SRS excluding the first haemorrhage was 11.08 per 100 CCM-years and was reduced to 2.7 per 100 CCM-years after *** recurrent event analysis,SRS,hR 0.27(95%CI 0.17 to 0.44),pd with a decreased risk of haemorrhage,and the presence of developmental venous anomaly(dVA)with an increased risk,hR 1.60(95%CI 1.07 to 2.40),p=*** cumulative risk of first haemorrhage after SRS was 9.4%(95%CI 6%to 12.6%)at 5 years and 15.6%(95%CI%9 to 21.8%)at 10 *** doses>13 Gy,hR 2.27(95%CI 1.20 to 4.32),p=0.012 and the presence of dVA,hR 2.08(95%CI 1.00 to 4.31),p=0.049 were factors associated with higher probability of post-SRS ***-SRS haemorrhage was symptomatic in 22 out of 381(5.8%)patients,presenting with transient(15/381)or permanent(7/381)neurological *** occurred in 11.1%(46/414)CCM and was responsible for transient neurological deficit in 3.9%(15/381)of the patients and permanent deficit in 1.1%(4/381)of the *** doses>13 Gy and CCM volume>0.7 cc were associated with increased risk of ARE.

关键词： doses haemorrhagic diagnosis

Optimization of Mass Bleed Control for Base drag Reduction of Supersonic Flight Bodies

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Journal of Thermal Science 2006年第3期15卷 206-212页

作者： Y.-K.Lee h.-d.Kim School of Mechanical Engineering Andong National University388 Songcheon-dongAndong760-749Korea

The minimization of base drag using mass bleed control is examined in consideration of various base to orifice exit area ratios for a body of revolution in the Mach 2.47 freestream Axisymmetric, compressible, rmss-averaged Navier-Stokes equations are solved using the standard k-ω model, a fully implicit finite volume scheme, and a second order upwind scheme. Base flow charcteristics are explained mgaarding the base configuration as well as the injection parameter which is defined as the mass flow rate of bleed jet non-dimensionalized by the product of the base area and fieestream mass flux. The results obtained through the present study show that for a smaller base area, the optimum mass bleed condition leading to minimum base drag occurs at relatively larger mass bleed, and a lalger orifice exit can offer better drag control.

关键词： base drag mass bleed drag reduction separation supersonic flow

Atomic-scale simulations of material behaviors and tribology properties for BCC metal film

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Chinese Physics B 2016年第1期25卷 412-418页

作者： h d Aristizabal P A Parra P Lopez E Restrepo-Parra PCM Computational Applications Universidad Nacional de Colombia-Sede ManizalesA.A.127ManizalesColombi Universidad Cató1ica de Manizales A.A.357ManizalesColombia

This work has two main purposes：（i） introducing the basic concepts of molecular dynamics analysis to material scientists and engineers, and （ii） providing a better understanding of instrumented indentation measurements, presenting an example of nanoindentation and scratch test simulations. To reach these purposes, three-dimensional molecular dynamics （Md） simulations of nanoindentation and scratch test technique were carried out for generic thin films that present BCC crystalline structures. Structures were oriented in the plane （100） and placed on FCC diamond substrates. A pair wise potential was employed to simulate the interaction between atoms of each layer and a repulsive radial potential was used to represent a spherical tip indenting the sample. Mechanical properties of this generic material were obtained by varying the indentation depth and dissociation energy. The load-unload curves and coefficient of friction were found for each test; on the other hand, dissociation energy was varied showing a better mechanical response for films that present grater dissociation energy. Structural change evolution was observed presenting vacancies and slips as the depth was varied.

关键词： molecular dynamics pair wise potential repulsive radial potential dissociation energy

Ultrafast magneto-optical dynamics in nickel(111)single crystal studied by the integration of ultrafast reflectivity and polarimetry probes

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Chinese Physics B 2024年第3期33卷 65-69页

作者：匡皓余军潇陈洁 h.E.Elsayed-Ali 李润泽 Peter M.Rentzepis School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China Center for Ultrafast Science and Technology Key Laboratory for Laser Plasmas (Ministry of Education)Collaborative Innovation Center of IFSA (CICIFSA)School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China department of Electrical and Computer Engineering Old Dominion UniversityNorfolkVirginia 23529USA department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTexas 77843USA

With the integration of ultrafast reflectivity and polarimetry probes,we observed carrier relaxation and spin dynamics induced by ultrafast laser excitation of Ni(111)single *** carrier relaxation time within the linear excitation range reveals that electron-phonon coupling and dissipation of photon energy into the bulk of the crystal take tens of *** the other hand,the observed spin dynamics indicate a longer time of about 120 *** further understand how the lattice degree of freedom is coupled with these dynamics may require the integration of an ultrafast diffraction probe.

关键词： ultrafast spin dynamics non-equilibrium dynamics multi-probe

Generic creep behavior and creep modeling of an aged surface support liner under tension

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第2期14卷 377-384页

作者： d.Guner O.Golbasi h.Ozturk department of Mining&Nuclear Engineering Missouri University of Science and TechnologyRollaMOUSA department of Mining Engineering Middle East Technical University(METU)AnkaraTurkey

Polymer-based materials have been motivated to be an alternative support system element in the mining/tunneling industry due to their logistic and geotechnical *** spray-on liner(TSL),a term to define the application of the material on the rock surface with a layer ranging from 2 mm to10 mm in thickness,shows some promising *** are mainly composed of plastic,polymer,or cement-based ingredients to a certain *** study intends to reveal the time-dependent response of TSL specimens,cured throughout 500 d,under four constant stress levels for stable laboratory *** results were correlated using two interrelated equations to predict the material’s service life(creep-rupture envelopes).The proposed correlations offered an insight into both the effective permanent support time and the strain amount at the liner *** time-dependent deformation of TSL,whose performance is highly responsive to creep behavior,was obtained so that the design engineers may use the findings to avoid the severe problems of material *** data were also used to develop a Burgers(four-element)creep *** the liner has a nonlinear time-dependent behavior,creep models were built for each stress level ***,a generic equation was obtained using the nonlinear parametric *** is a good agreement between the proposed model and the experimental *** proposed model can be used as a basis for future numerical studies related to the support behavior of aged surface support liners.

关键词： Time-dependent modeling Thin spray-on liner(TSL) Burgers model Creep constitutive model Stand-up time

Achieving superior strength-ductility synergy in a heterostructured magnesium alloy via low-temperature extrusion and low-temperature annealing

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Journal of Materials Science & Technology 2023年第32期163卷 32-44页

作者： h.Wang d.T.Zhang C.Qiu W.W.Zhang d.L.Chen Guangdong Key Laboratory for Advanced Metallic Materials Processing and Forming National Engineering Research Center of Near-net-shape Forming for Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China department of Mechanical and Industrial Engineering Toronto Metropolitan University(formerly Ryerson University)350 Victoria StreetTorontoON M5B 2K3Canada

A low-alloyed Mg-1.2Zn-0.1Ca(wt.%)alloy was fabricated via low-temperature extrusion and annealing at 250℃for different times(10,30,and 90 min)to attain heterostructures with different fine-grained fractions,focusing on the effect of heterostructure on the mechanical *** dynamic recrystallization(RX)occurred during extrusion at 150℃,and a lamellar structure consisting of fine RX grains and coarse unRX grains was *** subsequent annealing promoted static RX in the as-extruded alloy,leading to an increased fine-grained fraction from 67%to 95%.Meanwhile,the co-segregation of Zn and Ca atoms impeded the migration of grain boundaries,thus achieving a fine grain size of 0.8–1.6μ*** sample annealed for 10 min with a fine-grained fraction of 73%and an average RX grain size of 0.9μm exhibited a superior combination of high yield strength(305 MPa)and good ductility(20%).In comparison,an excellent elongation of 30%was achieved in the alloy with a nearly fully-RXed microstructure and an average grain size of 1.6μm after 90 min annealing,despite a lower yield strength of 228 *** unRX grains,the hard orientation with(01–10)parallel to the extrusion direction and high-density dislocations made it more difficult to deform compared with the RX grains,thus producing hetero-deformation induced(hdI)*** fine grains and high-density dislocations,hdI strengthening is the key to achieving the superior mechanical properties of the low-alloyed Mg alloy.

关键词： Low-alloyed magnesium alloy Low-temperature extrusion Annealing heterostructure Mechanical properties

Interaction of photons with silver and indium nuclei at energies up to 20 MeV

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Chinese Physics C 2024年第2期48卷 135-140页

作者： J.h.Khushvaktov M.A.demichev d.L.demin S.A.Evseev M.I.Gostkin V.V.Kobets F.A.Rasu-lova S.V.Rozov E.T.Ruziev A.A.Solnyshkin T.N.Tran E.A.Yakushev B.S.Yuldashev Joint Institute for Nuclear Research(JINR) DubnaRussia Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan(INP ASRU) TashkentUzbekistan Institute of Physics of the Vietnam Academy of Science and Technology(IP VAST) HanoiVietnam

The yields of photonuclear reactions in the 107Ag,113In,and 115In nuclei were *** Carlo simulations were performed using the Geant4 code,and the results were compared with the experimental *** isomeric ratios of the yields in the reactions 107Ag(γ,n)106m,gAg and 113In(γ,m)112m,gIn were determined,and the cross sections for the reactions 107Ag(γ,n)106gAg and 107Ag(γ,2n)105Ag at an energy of 20 MeV were calculated based on the experimental data.

关键词： 107Ag(γ,n)10mgAg and I13In(γ,n)12m-2In reactions cross section yield isomeric ratio simula-tion Geant4 TALYS

dEVELOPMENT OF NEW ThERMO-MEChANICAL SIMULATOR

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Acta Metallurgica Sinica(English Letters) 2004年第1期17卷 33-37页

作者： Z.G.Luo h.L.Su d.h.Zhang G.d.Wang X.h.Liu The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 ChinaThe State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 ChinaThe State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 ChinaThe State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 ChinaThe State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

A new multifunction thermo-mechanical simulator was successfully developed. The accuracy of measurement and control is very high through all digital control. More than twenty tests may be fulfilled including tension, compression, torsion, combination large deformation that meets the study of supersteel, etc. Its performance is introduced in the paper, such as designed ideas, machine structure, man-machine interface, control system, etc.

关键词： thermo-mechanical simulator multifunction control system combination large deformation