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Power management unit chip design for automobile active-matrix organic light-emitting diode display module

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journal of Central South University 2009年第4期16卷 621-628页

作者： kim j h PARK j h kim j h CAO T V LEE T Y BAN h j YANG K kim h G hA P B kim Y h Department of Electronic Engineering Changwon National University 9 Sarim-Dong Changwon 641-773 Korea Denso PS Electronics Corporation 47 Seongsan-Dong Changwon 641-315 Korea

A power management unit （PMU） chip supplying dual panel supply voltage, which has a low electro-magnetic interference （EMI） characteristic and is favorable for miniaturization, is designed. A two-phase charge pump circuit using external pumping capacitor increases its pumping current and works out the charge-loss problem by using bulk-potential biasing circuit. A low-power start-up circuit is also proposed to reduce the power consumption of the band-gap reference voltage generator. And the ring oscillator used in the ELVSS power circuit is designed with logic devices by supplying the logic power supply to reduce the layout area. The PMU chip is designed with MagnaChip＇s 0.25 μ high-voltage process. The driving currents of ELVDD and ELVSS are more than 50 mA when a SPICE simulation is done.

关键词： DC-DC converter AMOLED charge pumping power management unit (PMU) dual panel supply voltage

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

Safety estimation of high-pressure hydraulic cylinder using FSI method

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排灌机械工程学报 2016年第5期34卷 418-423页

作者： kim j.h. hAN S.M. kim Y.j. Graduate School of Mechanical Engineering Sungkyunkwan University Suwon 16419 Republic of Korea hKC CO. Ltd. Ansan 425 - 836 Republic of Korea School of Mechanical Engineering Sungkyunkwan University Suwon 16419 Republic of Korea

hydraulic cylinder is a primary component of the hydraulic valve *** numerical study of hydraulic cylinder to evaluate the stress analysis,the life assessment and the performance of operation characteristics in hydraulic cylinder were *** calculation of safety factor,fatigue life,piston chamber pressure,rod chamber pressure and the change of velocity of piston with flow time after the beginning of hydraulic cylinder were *** analysis was performed using the commercial CFD code,ANSYS with unsteady,dynamic mesh model,two-way FSI(fluid-structure interaction)method and k-εturbulent *** internal pressure in hydraulic cylinder through stress analysis show higher than those of the yield strength.

关键词： two-way fluid-structure interaction high-pressure hydraulic cylinder durability life safety estimation dynamic mesh

Fault detection method with PCA and LDA and its application to induction motor

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journal of Central South University 2010年第6期17卷 1238-1242页

作者： jUNG D Y LEE S M 王洪梅 kim j h LEE S h Daeho Tech Company Limited Department of Electronics Engineering Inha University School of Mechatronics Changwon National University

A feature extraction and fusion algorithm was constructed by combining principal component analysis(PCA) and linear discriminant analysis(LDA) to detect a fault state of the induction *** yielding a feature vector with PCA and LDA from current signal that was measured by an experiment,the reference data were used to produce matching *** a diagnostic step,two matching values that were obtained by PCA and LDA,respectively,were combined by probability model,and a faulted signal was finally *** the proposed diagnosis algorithm brings only merits of PCA and LDA into relief,it shows excellent performance under the noisy *** simulation was executed under various noisy conditions in order to demonstrate the suitability of the proposed algorithm and showed more excellent performance than the case just using conventional PCA or LDA.

关键词： principal component analysis (PCA) linear discriminant analysis (LDA) induction motor fault diagnosis fusionalgorithm

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： h.T.jeong S.W.Lee W.j.kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the hCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

A Proposed Core Catcher System and Thermite Experimental Results

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journal of Energy and Power Engineering 2011年第11期5卷 1005-1014页

作者： h.Y. kim j.h. kim K.S. ha j.h. Song j.h. Park Thermal hydraulics Safety Research Division Korea Atomic Energy Research Institute Daejeon 305-353 Korea

To prevent direct contact of the melt and basemat concrete of the cavity in a postulated core melt accident, a core catcher concept is suggested. Upon ablation of the sacrificial layer on top of the core catcher while molten core material is discharged, a mixture of water and gas is injected from below. It is expected that a simultaneous injection of water and gas could prevent a possible steam explosion/spike and also suppress the rapid release of steam which might result in fast over-pressurization of the containment. A test facility for the core catcher using a thermite reaction technique for the generation of the melt was designed and constructed at Korea Atomic Energy Research Institute （KAERI）. The first series of tests were performed by using a mixture of Al, Fe2O3, and CaO as a stimulant. As a first try, only water was injected from the bottom of the melt through five water injection nozzles when the melt front reached the water injection nozzles. A description of the test facility for the core catcher, the thermite composition, and the methods of experiment is included. The test results are discussed.

关键词： Core catcher corium cooling sacrificial layer water injection severe accidient thermite reaction.

热输入对F69A4-ECM4-M4金属芯埋弧焊丝熔敷金属组织和力学性能的影响

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焊接学报 2018年第1期39卷 50-54页

作者：温培银栗卓新齐勇田张天理 kim h j 北京工业大学材料科学与工程学院北京100124 韩国工业技术研究院高级熔焊研究组

采用F69A4-ECM4-M4金属芯埋弧焊丝在不同的热输入(18.67,20.57,22.56,24.63 k j/cm)下焊接熔敷金属,并通过光学显微镜和扫描电镜对其组织进行了观察分析,采取冲击试验方法测试冲击韧性.结果表明,不同热输入的熔敷金属其组织形态和数量... 详细信息

采用F69A4-ECM4-M4金属芯埋弧焊丝在不同的热输入(18.67,20.57,22.56,24.63 k j/cm)下焊接熔敷金属,并通过光学显微镜和扫描电镜对其组织进行了观察分析,采取冲击试验方法测试冲击韧性.结果表明,不同热输入的熔敷金属其组织形态和数量也有着明显的差异;随着热输入的增加,其熔敷金属中柱状晶的宽度逐渐增大,-40℃的冲击韧性逐渐降低,断口形貌中放射区比例逐渐增加.当热输入为18.67 k j/cm时,熔敷金属显微组织主要由细小的针状铁素体组成,冲击吸收功达到最大值139 j.随着热输入的增加,熔敷金属高温停留时间长,熔敷金属组织中针状铁素体晶粒急聚长大,从而导致熔敷金属冲击韧性的下降.

关键词：热输入金属芯埋弧焊丝熔敷金属组织冲击韧性

柔性直流输电并网风电厂的低电压穿越能力改进(英文)

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电力系统自动化 2015年第3期39卷 14-22页

作者： Ranjan ShARMA Qiuwei WU Seung Tae ChA kim hφj jENSEN Tony Wederberg RASMUSSEN jacob ΦSTERGAARD Siemens Wind Power A/S Center for Electric Power and Energy Department of Electrical EngineeringTechnical University

To achieve active control of the AC voltage magnitude of wind power plant(WPP)collector network and improve the fault ride-through(FRT)capability,an FRT scheme based on feed forward DC voltage control is presented for voltage source converter-high voltage direct current(VSC-hVDC)connected offshore *** steady state operation,an open loop AC voltage control is implemented at the WPP-side VSC of the hVDC system so that any possible control interactions between WPP-side VSC and VSC of wind turbine are *** during any grid fault,a dynamic AC voltage reference is made according to both the DC voltage error and AC active current from the WPP collector system,thus ensuring fast and robust FRT of the VSC-hVDC-connected offshore *** the unbalanced fault condition in the host power system,the resulting oscillatory DC voltage is directly used in the VSC AC voltage controller at the WPP side so that the WPP collector system voltage also reflects the unbalance in the main *** domain simulations are performed to verify the efficacy of the FRT scheme based on the proposed feed forward DC voltage *** results show satisfactory FRT responses of the VSC-hVDC-connected offshore WPP under balanced and unbalanced faults in the host power system,as is shown under a serious fault in the WPP collector network.

关键词：电网故障连接海上能力直流输电系统电压控制器不平衡故障电厂

Boosted Lithium-Ion Transport Kinetics in n-Type Siloxene Anodes Enabled by Selective Nucleophilic Substitution of Phosphorus

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Nano-Micro Letters 2024年第10期16卷 618-637页

作者： Se In kim Woong-ju kim jin Gu Kang Dong-Wan kim School of Civil Environmental and Architectural EngineeringKorea University02841 SeoulSouth Korea Nanophotonics Research Center Korea Institute of Science and Technology02792 SeoulSouth Korea

Doped two-dimensional(2D)materials hold significant promise for advancing many technologies,such as microelectronics,optoelectronics,and energy ***,n-type 2D oxidized Si nanosheets,namely n-type siloxene(n-SX),are employed as Li-ion battery *** thermal evaporation of sodium hypophosphite at 275℃,P atoms are effectively incorporated into siloxene(SX)without compromising its 2D layered morphology and unique Kautsky-type crystal ***,selective nucleophilic substitution occurs,with only Si atoms being replaced by P atoms in the O_(3)≡Si-h *** resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types:(i)P atoms residing in Si sites and(ii)h *** doping concentrations are varied by controlling the amount of precursors or their mean free *** at 2000 mA g^(-1),the n-SX electrode with the optimized doping concentration(6.7×10^(19) atoms cm^(-3))delivers a capacity of 594 mAh g^(-1) with a 73%capacity retention after 500 *** improvements originate from the enhanced kinetics of charge transport processes,including electronic conduction,charge transfer,and solid-state *** approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage.

关键词： Li-ion battery Two-dimensional N-type siloxene Doping mechanism Kinetics