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World Journal of Radiology 2013年第1期5卷 5-16页

作者： Hans U Kerl Lars Gerigk marc A Brockmann Sonia Huck mansour AlZghloul Christoph Groden Thomas Hauser Armin m Nagel Ingo S Nlte Department of Neuroradiology University Medical Center MannheimUniversity of Heidelberg68167 MannheimGermany Division of Radiology German Cancer Research Center69120 HeidelbergGermany Department of medical Physics and Radiology German Cancer Research Center69120 HeidelbergGermany

AIm:To evaluate different promising magnetic resonance imaging(mRI) methods at 7.0 Tesla(T) for the pre-stereotactic visualization of the zona incerta(ZI).mETHODS:Two neuroradiologists qualitatively and quantitatively examined T2-turbo spin-echo(T2-TSE),T1-weighted gradient-echo,as well as FLASH2D-T2Star and susceptibility-weighted imaging(SWI) for the visualization of the ZI at 7.0 T *** and image quality for the ZI were independently examined using a 6-scale grading ***-rater reliability using Cohen's kappa coefficient(κ) were ***-tonoise ratios(CNR),and signal-to-noise ratios(SNR) for the ZI were calculated for all *** in delineation,SNR,and CNR between the sequences were statistically assessed using a paired *** the anatomic validation the coronal FLASH2D-T2Star images were co-registered with a stereotactic atlas(Schaltenbrand-Wahren).RESULTS:The rostral part of the ZI(rZI) could easily be identified and was best and reliably visualized in the coronal FLASH2D-T2Star *** caudal part was not definable in any of the *** major artifacts in the rZI were observed in any of the ***2D-T2Star and SWI imaging offered significant higher CNR values for the rZI compared to T2-TSE images(P > 0.05).The co-registration of the coronal FLASH2D-T2Star images with the stereotactic atlas schema(Schaltenbrand-Wahren) confirmed the correct localization of the ZI in all ***:FLASH2D-T2Star imaging(particularly coronal view) provides the reliable and currently optimal visualization of the rZI at 7.0 *** results can facilitate a better and more precise targeting of the caudal part of the ZI than ever before.

关键词： Deep brain stimulation Essential tremor magnetic resonance imaging Parkinson’s disease Zona incerta 7 Tesla

Cross-Tier Interference mitigation in 3D HetNets for lte and Wi-Fi Access

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Intelligent Automation & Soft Computing 2023年第1期35卷 1211-1227页

作者： m.Rekha m.Bhuvaneswari Department of Electronics and Communication Engineering Dhanalakshmi Srinivasan Engineering College(Autonomous)Perambalur621212Tamil NaduIndia Department of Electronics and Communication Engineering Anna University BIT campusTiruchirappalli620024Tamil NaduIndia

Due to the unprecedented rate of transformation in thefield of wireless communication industry,there is a need to prioritise the coverage,network power and throughput as *** Heterogeneous Networks(HetNets)the low power node inclusion like Femto and Pico cells creates a network of multi-Tier(m-Tier)which is regarded as the most significant strategy for enhancing the coverage,throughput,4G Long Term Evolution(lte)*** work mainly focuses on m-Tier 3D Heterogeneous Networks Energy Efficiency(EE)based Carrier Aggregation(CA)scheme for streaming real-time huge data like ***,m-Tier 3D HetNets scheme was made for investigating Signal to Noise Interference Ratio(SNIR)on assessing the collective Pico-tier and Femto-tier ***,the scheme of channel allocation is scrutinised so as to esti-mate throughput from the multiple ***,with the use of CA technique,the problem of energy efficiency for m-Tier 3D Heterogeneous Network(HetNet)in relation to energy metrics and throughput was evaluated with the use of lte and Wireless Fidelity(Wi-Fi)*** simulation is carried out in a mATLAB setting,and the outcomes reveal a huge impact on *** simulation is carried in terms of EE,transmission time,throughput,packet success rate,convergence probability,and coverage *** analysis from simu-lation shows that on improving the output of the device,interference among small cell base stations is reduced on increasing *** outcomes attained aid in the effective creation of m-Tier 3D HetNets for enhancing EE by employing multi-Stream Carrier Aggregation(mSCA)in HetNets.

关键词： Heterogeneous networks multi-tier 3D HetNets energy efficiency carrier aggregation lte Wi-Fi

Time-Resolved Emission Spectroscopic Study of Laser-Induced Steel Plasmas

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Plasma Science and Technology 2013年第6期15卷 546-551页

作者： m.L.SHAH A.K.PULHANI B.m.SURI G.P.GUPTA Laser and Plasma Technology Division Bhabha Atomic Research CentreMumbai-400 085India

Laser-induced steel plasma is generated by focusing a Q-switched Nd：YAG visible laser（532 nm wavelength） with an irradiance of 1 x 109 W/cm2 on a steel sample in air at atmospheric *** Echelle spectrograph coupled with a gateable intensified charge-coupled detector is used to record the plasma *** time-resolved spectroscopic measurements of the plasma emissions,the temperature and electron number density of the steel plasma are determined for many times of the detector *** validity of the assumption by the spectroscopic methods that the laser-induced plasma（LIP） is optically thin and is also in local thermodynamic equilibrium.lte） has been evaluated for many delay *** the temporal evolution of the intensity ratio of two Fe I lines and matching it with its theoretical value,the delay times where the plasma is optically thin and is also in lte are found to be 800 ns,900 ns and 1000 ns.

关键词： laser-induced plasma steel emission spectroscopy plasma temperature and electron number density

measurement of the pion form factor for m_(ππ)～2 between 0.1 and 0.85 GeV^2 with the kloe detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan E.müller Institut für Kernphysik Johannes Gutenberg-Universitt

The kloe experiment at the φ-factory DAФPNE has measured the pion form factor in the range between 0.1 〈 mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the mππ^2 region covered by kloe ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

EFFICIENT SIXTH ORDER P-STABLE mETHODS WITH mINImAL LOCAL TRUNCATION ERROR FOR y"=f(x,y)

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Journal of Computational mathematics 2002年第2期20卷 175-184页

作者： Kai-li Xiang R.m.Thomas Department of Computer Science Southwest Petroleum InstituteNanchong 637001China Department of mathematics UMISTManchesterM60 1 QDUK

A family of symmetric (hybrid) two step sixth P-stable methods for the accurate numerical integration of second order periodic initial value problems have been considered in this paper. These methods, which require only three (new) function evaluation per iteration and per step integration. These methods have minimal local truncation error (lte) and smaller phase-lag of sixth order than some sixth orders P-stable methods in [1-3,10-11]. The theoretical and numerical results show that these methods in this paper are more accurate and efficient than some methods proposed in [1-3,10].

关键词： second order periodic initial value problems P-stable phase-lag local truncation error

Effect of radiation on compressibility of hot dense sodium and iron plasma using improved screened hydrogenic model with𝑙splitting

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Chinese Physics B 2021年第3期30卷 225-236页

作者： Amjad Ali G Shabbir Naz Rukhsana Kouser Ghazala Tasneem m Saleem Shahzad Aman-ur-Rehman m H Nasim Department of Physics and Applied mathematics Pakistan Institute of Engineering and Applied SciencesIslamabad 45650Pakistan Department of Nuclear Engineering Pakistan Institute of Engineering and Applied SciencesIslamabad 45650Pakistan

High pressure investigations of matter involve the study of strong shock wave dynamics within the materials which gives rise to many thermal effects leading to dissociation of molecules,ionization of atoms,and radiation emission,*** response of materials experiencing a strong shock can be determined by its shock Hugoniot calculations which are frequently applied in numerical and experimental studies in inertial confinement fusion,laboratory astrophysical plasma,*** studies involve high energy density plasmas in which the radiation plays an important role in determining the energy deposition and maximum compressibility achieved by the shock within *** this study,we present an investigation for the effect of radiation pressure on the maximum compressibility of the material using shock Hugoniot *** shock Hugoniot calculations,an equation of state(EOS)is developed in which electronic contributions for EOS calculations are taken from an improved screened hydrogenic model with−l splitting(I-SHmL)[High Energy Density Physics(2018)2648]under local thermodynamic equilibrium.lte)*** thermal ionic part calculations are adopted from the state of the art Cowan model while the cold ionic contributions are adopted from the scaled binding energy *** Shock Hugoniot calculations are carried out for sodium and iron plasmas and our calculated results show excellent agreement with published results obtained by using either sophisticated self-consistent models or the first principle study.

关键词： self-consistent-field methods thermodynamics of plasmas average atom model shock Hugoniot calculation

Numerical and Experimental Investigation on the In-Flight melting Behaviour of Granulated Powders in Induction Thermal Plasmas

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Plasma Science and Technology 2009年第1期11卷 71-77页

作者：姚耀春 md.m.HOSSAIN T.WATANABE National Engineering Laboratory of Vacuum metallurgy Kunming University of Science and Technology Department of Environmental Chemistry and Engineering Tokyo Institute of Technology Department of Electronics and Communications Engineering East West University

An innovative in-flight glass melting technology with thermal plasmas was developed for the purpose of energy conservation and environment protection. In this study, modelling and experiments of argon-oxygen induction thermal plasmas were conducted to investigate the melting behaviour of granulated soda-lime glass powders injected into the plasma. A two-dimensional local thermodynamic equilibrium （lte） model was performed to simulate the heat and momentum transfer between plasma and particle. Results showed that the particle temperature was strongly affected by the flow rate of carrier gas and the particle size of raw material. A higher flow rate of carrier gas led to lower particle temperature and less energy transferred to particles which resulted in lower vitrification. The incomplete melting of large particles was attributed to the lower central temperature of the particle caused by a larger heat capacity. The numerical analysis explained well the experimental results, which can provide valuable practical guidelines for the process control in the melting process for the glass industry.

关键词： induction thermal plasmas size. heat transfer numerical modelling carrier gas flow rate particle

Elite Opposition Based metaheuristic Framework for Load Balancing in lte Network

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Computers, materials & Continua 2022年第6期71卷 5765-5781页

作者： m.R.Sivagar N.Prabakaran Department of Computer Science and Engineering Sathyabama Institute of Science&TechnologyChennai600119India Department of Electronics and Communication Engineering Koneru Lakshmaiah Education FoundationGuntur522502Andhra PradeshIndia

In present scenario of wireless communications,Long Term Evolution(lte)based network technology is evolved and provides consistent data delivery with high speed andminimal delay through mobile *** traffic management and effective utilization of network resources are the key factors of lte ***,there are some major issues in lte that are to be considered are effective load scheduling and traffic *** lte is a depraved technology,it is been suffering from these *** addressing that,this paper develops an Elite Opposition based Spider monkey Optimization Framework for Efficient Load Balancing(SmO-ELB).In this model,load computation of each mobile node is done with Bounding Theory based Load derivations and optimal cell selection for seamless communication is processed with Spider monkey Optimization *** simulation results show that the proposed model provides better results than exiting works in terms of efficiency,packet delivery ratio,Call Dropping Ratio(CDR)and Call Blocking Ratio(CBR).

关键词： Spider monkey optimization load balancing long term evolution optimal cell selection handover lte networks QoS

Investigation of electron beam effects on L-shell mo plasma produced by a compact LC generator using pattern recognition

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matter and Radiation at Extremes 2019年第2期4卷 52-58页

作者： m.F.Yilmaz Y.Danisman m.Ozdemir B.Karlık J.Larour Basic Sciences Engineering DepartmentImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of mathematics and Computer Sciences Queensborough Community CollegeCUNYBaysideNew York 11364USA Neurosurgical Simulation Research and Training Centre Department of NeurosurgeryMontreal Neurological Institute and HospitalMcGill UniversityMontrealQuebec H3A 2B4Canada Laboratoire de Physique des Plasmas(LPP) Ecole PolytechniqueUPMCCNRSPalaiseauFrance

In this paper,the effects of an electron beam on X-pinch-produced spectra of L-shellmoplasma are investigated for the first time by principal component analysis(PCA);this analysis is compared with that of line ratio diagnostics.A spectral database for PCA extraction is arranged using a non-Local Thermodynamic Equilibrium(non-lte)collisional radiative L-shell mo *** vector spectra of L-shell mo,including F,Ne,Na and mg-like transitions are studied to investigate the polarization types of these ***1 vector spectra of F,Ne,Na and mg-like transitions result in linear polarization of Stokes Q ***,PC2 vector spectra show linear polarization of Stokes U profiles of 2p^(5)3s of Ne-like transitions which are known as responsive to a magnetic field[Trabert,Beiersdorfer,and Crespo Lo´pez-Urrutia,*** ***.,Sect.B 408,107–109(2017)].A 3D representation of PCA coefficients demonstrates that addition of an electron beam to the non-lte model generates quantized,collective clusters which are translations of each other that follow V-shaped cascade trajectories,except for the case f=*** extracted principal coefficients are used as a database for an Artificial Neural Network(ANN)to estimate the plasma electron temperature,density and beam fractions of the time-integrated,spatially resolved L-shellmoX-pinch plasma ***-based ANNs provide an advantage in reducing the network topology,with a more efficient backpropagation supervised learning *** modeled plasma electron temperature is about Te;660 eV and density n_(e)=1×10^(20) cm^(-3),in the presence of the fraction of the beams with f-0.1 and centered energy of 5 keV.

关键词： spectrum. beam transitions