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Journal of Materials Science & Technology 2004年第4期20卷 459-462页

作者： ZhenhuaWAnG ZhidongZHAnG c.J.choi B.K.kim J.c.kim ShenyangnationalLaboratoryforMaterialsScienceandInternationalcentreforMateri~alsPhysics InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China KoreaInstituteofMachineryandMaterials 66Sangnam-DongChangwonKyungnam641-010Korea

nanoparticles of Fe-co alloys and their oxides with the particle size below 20 nm were prepared by chemical vapor condensation process. The pure Ar, Ar+1%O2, Ar+3%O2 and Ar+6%O2 were used as carrier gases, with iron carbonyl and cobalt carbonyl as the precursors. XRD patterns showed that Fe-co metallic nanoparticles were synthesized by using pure Ar as carrier gas, and only metal oxides were obtained using Ar+(>3)%O2 as carrier gas. The HRTEM images and TG-DTA curves were used to study the core-shell structure of the different nanoparticles. The nanoparticles obtained in pure Ar consist of black core and light shell with thickness of 2~4 nm. However, in the particles obtained in Ar+6%02, the oxides core with visible lattice fringes are surrounded by thin shell.

关键词： Fe-co nanoparticles HRTEM cVc

current Status of the KSTAR Engineering

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Plasma Science and Technology 2004年第1期6卷 2159-2165页

作者： J.S.Bak K.kim c.H.choi Y.K.Oh B.c.kim n.I.Her H.L.Yang G.S.Lee the KSTAR Team Korea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 KoreaKorea Basic Science Institute 52 Yeoeun-Dong Yusung-Ku Daejeon 305-333 Korea

As there is substantial progress in the KSTAR tokamak engineering, all themajor structures and sub-systems are under fabrication and in procurement phase. The vacuum vessel,port, cryostat cylinder, lid, and bellows are being rigorously fabricated in the factory. The lowerpart of the KSTAR such as cryostat base and gravity support has been almost finished in itsfabrication. There are also great progresses and significant results in manufacturing of thesuperconducting magnet, including four Toroidal Field (TF) coils, lower and upper PF7 coils whichare the largest Poloidal Field (PF) coils. The TFOO coil, which has been made for test and back-upof the TF magnet system, was successfully tested in the cool-down and current charging. As thefabrications and procurements of major structures have been actively proceeded, assembly works werealso launched from Aug. 2003. More detailed description on these status, results, and plans will bedescribed in this paper.

关键词： KSTAR tokamak vacuum vessel magnet cryostat tokamak assembly

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： n c ROY M R TALUKDER A n cHOWDHURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh Bangladesh council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(ROS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Shape of the geometrically active atomic states of carbon

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chinese Physics B 2010年第2期19卷 219-224页

作者：熊庄 Bacalis n.c. AMS Research center Southeast University Theoretical and Physical chemistry Institute National Hellenic Research FoundationVasileos Constantinou 48AthensGreece 11635

We have developed a computer code for {／em ab initio} the variational configuration interaction calculation of the electronic structure of atoms via variationally optimized Lagurre type orbitals, treating the orbital effective charges as variational parameters. Excited states of the same symmetry, in order to avoid the inherent restrictions of the standard method of Hylleraas--Unheim and MacDonald, are computed variationally by minimizing the recently developed minimization functionals for excited states. By computing, at the minimum, the one-electron density and the probability distribution of the two-electron angle, and the most probable two-electron angle, we investigate the atomic states of the carbon atom. We show that, without resorting to the （admittedly unproven） concept of hybridization, as an intrinsic property of the atomic wave function, the most probable value of the two-electron angle is around the known angles of carbon bonding, i.e. either 109^／circ or 120^／circ or 180^／circ, depending on each low-lying state of the bare carbon atom.

关键词： carbon hybridization excited states variational principle

clustering-based label estimation for network anomaly detection

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Digital communications and networks 2021年第1期7卷 37-44页

作者： Sunhee Baek Donghwoon Kwon Sang c.Suh Hyunjoo kim Ikkyun kim Jinoh kim computer Science Department Texas A&M UniversityCommerceTX75429USA ETRI 218 Gajeong-roYuseong guDaejeon34129Republic of Korea

A substantial body of work has been done to identify network anomalies using supervised and unsupervised learning techniques with their unique strengths and *** this work,we propose a new approach that takes advantage of both worlds of unsupervised and supervised *** main objective of the proposed approach is to enable supervised anomaly detection without the provision of the associated labels by *** this end,we estimate the labels of each connection in the training phase using ***“estimated”labels are then utilized to establish a supervised learning model for the subsequent classification of connections in the testing *** set up a new property that defines anomalies in the context of network anomaly detection to improve the quality of estimated *** our extensive experiments with a public dataset(nSL-KDD),we will prove that the proposed method can achieve performance comparable to one with the “original”labels provided in the *** also introduce two heuristic functions that minimize the impact of the randomness of clustering to improve the overall quality of the estimated labels.

关键词： Label estimation network anomaly detection clustering randomness

Leveraging ROTI map derived from Indonesian GnSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan n.Muafiry Teguh n.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo Febrylian F.chabibi Umar A.Ahmad Wildan P.Tresna Asnawi Research center for climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management Facilities and Science and Technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s GnSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GnSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia continuously Operating Reference Station(Ina-cORS)network comprises over 300 GnSS receivers spanning equatorial to southern low-latitude ***-cORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron content(TEc)change index(ROTI)derived from this *** generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROTI maps of Ina-cORS are ***,the Ina-cORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROTI maps from Ina-cORS and GnSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROTI maps from Indonesia and integrating them with regional GnSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GnSS receivers’network Indonesia continuously Operating Reference Station(Ina-cORS) ionospheric map Rate of TEc change index(ROTI)map

numerical simulation and experimental study for rheo-forged component using direct and indirect die system

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Transactions of nonferrous Metals Society of china 2010年第9期20卷 1799-1804页

作者： H.H.kim c.G.KAnG Precision Manufacturing Systems Division Pusan National University School of Mechanical Engineering Pusan National University

Sand casting and die casting processes have been used widely for complex automotive products such as knuckle, arm, ***, a part fabricated by casting has limited strength due to manufacturing defects such as the dendrite structure, segregation and *** an attempt to offer a solution to these problems, forging has been used as an alternative ***, the forging process provides limited formability for complex shape ***-forging of metal offers not only superior mechanical strength but also requires significantly lower machine loads than solid forming *** order to produce semi-solid materials of the desired microstructure, a stirring process is applied during solidification of molten *** results of an A356 aluminum alloy sample, which are obtained by experiment and by simulation using DEFORM 3D, are present.

关键词： rheo-forging A356 alloy formability forming defects

Effect of Solute contents of Al-ni-Sr Alloy on Glass Forming Ability and Thermal Stability

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Journal of Rare Earths 2004年第Z2期22卷 73-77页

作者： Taek Soo kim J K Lee H J kim J c Bae Advanced Materials R&D center Korea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea Advanced Materials R&D CenterKorea Institute of Industrial Technology994-32 Dongchun-dongYeonsu-kuIncheon 406-130Korea

Glass forming ability (GFA) and structural characterization of a new amorphous Al-ni-Sr alloy melt spun were investigated on the theory of the factors for the glass formation. The GFA was varied with the ratio of ni to Sr in detail and successful amorphous phase dispersed with 2 ～ 5 nm precipitates was prepared from Al-ni5-Sr3. Thermal stability and crystallization behavior of the amorphous phase were determined by continuous and isothermal heating technique on DcS, resulting that the crystallization occurs by the growth of fcc Al nanocrystals on the preexistent nuclei.

关键词： glass formation crystallization Al base amorphous alloys rapid solidification

Quality incentive based congestion control for multimedia communication over IP networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第Z1期7卷 7-12页

作者： JOHAnSEn Stian kim Anna n. PERKIS Andrew centre for Quantifiable Quality of Service in communication Systems norwegian University of Science and Technology Trondheim N-7034Norway

In this paper we introduce a framework for using quality as an incentive to promote proper application level congestion control. Through integrating a joint-source channel coder and feedback-based congestion control scheme, we are able to construct accurate and efficient quality incentives. The framework is applicable in all network architectures where end-to-end congestion control may be used, and is as such not specific to either best-effort or traffic class-based architectures. The concept is presented along with preliminary simulations that highlight the resulting rate control accuracy. We also discuss how to implement some well-known congestion control schemes within our framework.

关键词： congestion control, Incentives, Video communication, Joint source/channel coding, Unequal error protection

Stellar energy loss rates associated with photoneutrino processes in the minimal extension of the standard model

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chinese Physics c 2023年第4期47卷 74-80页

作者： c.Aydın Department of Physics Karadeniz Technical University61080TrabzonTurkey

Using the minimal extension of the standard model and considering the charge radius and the anapole moments of a neutrino,we derive analytical expressions for the stellar energy loss rates associated with the production of a neutrino pair e+γ→ve+ve νein hot plasma under three limiting regimes(nondegenerate,intermediate,and degenerate electrons)of the temperature,electron chemical potential,and plasma *** obtained results reveal the presence of an extra contribution of approximately 10%based on the considered calculations.

关键词： neutrinos pair production stellar energy-loss rates form factors electron-positron plasmas