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Analyzing the h19-and T65-epitopes in 38 kd phosphory-lated protein of Marek's disease viruses and comparing chicken immunological reactions to viruses point-mutated in the epitopes

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Science China(Life Sciences) 2004年第1期47卷 82-91页

作者： lee Lucy F Avian Disease and Oncology Laboratory East Lansing Ml 48823 USA

DNA sequencing analysis in 38 kd phosphorylated protein (pp38) ORF of Marek's disease viruses (MDV) indicated that all tested 10 virulent strains with different pathotypes had 'A' at base #320 and glutamine at aa#107 while reacted with monoclonal antibody (Mab) h19 in indirect fluorescence antibody test (IFA). however, vaccine strain CVI988 had 'G' at base#320 and arginine at aa#107 instead, when it was negative in IFA with Mab h19. Some strains were also reactive with Mab T65 in IFA while there was 'G' at base #326 and glycine at aa#109, but the other strains, which had 'A' at base #326 and glutamic acid at aa#109, did not react with Mab T65. By comparison of CVI988 to its point mutants CVI/rpp38(AG) and CVI/rpp38(AA) with 1 or 2 base(s) changes at bases #320 and /or #326 of pp38 gene for their reactivity with Mab h19 and T65, it was confirmed that the glutamine at aa#107 and glycine at aa#109 were critical to epitopes h19 and T65 respectively. Immuno-reactions to MDV were compared in SPF chickens inoculated with cloned CVI988 and its mutant CVI/rpp38(AG). It was found that antibody responses to MDV in chickens inoculated with CVI/rpp38(AG) were delayed and significantly lower than that in chickens inoculated with the native CVI988. By differential comparison of antibody titers to different antigens, a third epitope specific to CVI988 and dependent on arginine at aa#107 was suggested to be responsible for the big difference in antibody responses induced by native CVI988 and its mutant.

关键词： Marek's disease virus, pp38 gene, point mutant, epitopes, antibody responses.

Turbulent lock release gravity current

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Science China(Technological Sciences) 2001年第5期44卷 449-462页

作者：陈国谦 Joseph h.w.lee National Laboratory for Turbulence Research Department of Mechanics Peking University Beijing 100871China

The time evolution of a turbulent lock release gravity current, formed by a finite volume ofhomogeneous fluid released instantaneously into another fluid of slightly lower density, was studied byexperimental measurements of the density structure via elaborate digital image processing and by a nu-merical simulation of the flow and mixing using a two-equation turbulence model. The essential fact thatthe gravity current passes through an initial slumping phase in which the current head advances steadilyand a second self-similar phase in which the front velocity decreases like the negative third power of thetime after release is satisfactorily presented by the laboratory observation. An overall entrainment ratioproportional to the distance from the release point is found by the numerical simulation. The renormal-ization group (RNG) k- ε model for Reynolds-stress closure is validated to characterize the gravitycurrent with transitional and localized turbulence.

关键词： turbulence modeling, gravity current, environmental hydraulics.

A wide band fully-integrated CMOS oscillator tuned by a switched transformer

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A wide band fully-integrated CMOS oscillator tuned by a swit...

Model-based adaptive locomotion and clustering control of microparticles through ultrasonic topological charge modulation

2005年海峡两岸三地无线科技学术会

作者： J.-W.hsu S.-h.lee J.-F.lee S.-L.Jang Department of Electronic Engineering Taiwan University of Science and Technology 43 Keelung Road Section 4 Taipei

This paper presents a new CMOS LC VCO topology for wide-band application. The LC resonator consists of a switchable transformer with control transistors and varactors formed of accumulation mode MOS. The VCO has two control switching transistors to vary the effective resonator inductance, which is used to coarse-tune VCO output frequency, and MOS varactor is used to fine-tune the output frequency. It has been fabricated by using the 0.18 um 1P6M CMOS technologies and consumes current of 5.2 mA at 1.8 V supply voltage. The measured phase noise is -109.5 dBc/hz at 1Mhz offset from the oscillation frequency of 1.95Ghz. The frequency can be tuned from to l.8Ghz to 3.38Ghz.

关键词： Index Terms-CMOS Voltage-controlled oscillator (VCO) voltage controlled transformer tuning range

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Applied Mathematics and Mechanics(English Edition) 2023年第4期44卷 623-640页

作者： h.S.lee h.X.CAO D.JUNG C.S.KIM School of Mechanical Engineering Chonnam National UniversityGwangju 61186South Korea Korea Institute of Medical Microrobotics Gwangju 61011South Korea

We present a novel motion control technique for microrobot clusters to exploit the characteristics of the ultrasonic *** method comprises two steps,i.e.,introducing an ultrasonic actuation(UA)linear model for three-dimensional(3D)locomotion and controlling the topological charge(TC)in the ultrasonic vortex for microrobot ***,the TC is a controllable parameter for the expansion and contraction of the pressure null space inside the *** present a TC control method to cluster sporadically distributed microrobots in a specific *** validate the concept,a UA system composed of 30 ultrasonic transducers with 1 Mhz frequency is fabricated,and the characteristics of the generated acoustic pressure field are analyzed through ***,the performances of the adaptive controller for precise 3D locomotion and the TC control method for clustering are ***,the UA technology,which performs both clustering and locomotion in a complex manner,is validated with a gelatin phantom in an in-vitro environment.

关键词： ultrasonic actuation(UA) topological charge(TC) adaptive control particle manipulation

Numerical modelling of a low power non-transferred arc plasma reactor for methane conversion

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Plasma Science and Technology 2019年第6期21卷 29-37页

作者： B I MIN D K DINh D h.lee T h KIM S ChOI Institute for Nuclear Science and Technology Jeju National University 102 Jejudaehak-ro Jeju 63243Republic of Korea University of Science and Technology(UST) 217 Gajeong-ro Yuseong-gu Daejeon 34113 Republic of Korea Korea Institute of Machinery and Materials 156 Gajeongbuk-ro Yuseong-gu Daejeon 34103 Republic of Korea Department of Nuclear and Energy Engineering Jeju National University 102 Jejudaehak-ro Jeju 63243Republic of Korea

Thermal flow characteristics and the methane conversion reaction in a low power arc plasma reactor for efficient storage and transport of methane,which is the main component of shale gas,were *** temperature and velocity distributions were calculated according to the type of discharge gases and arc current level by a self-developed magnetohydrodynamics (MhD)code and a commercial ANSYS-FLUENT code;the transport of chemical species was analyzed as including the chemical reactions of methane *** simulated results were verified by the comparison of calculated and measured arc voltages with permissible low error as under 4%.Three C2 hydrocarbon gases with ethane (C2h6),ethylene (C2h4),and acetylene (C2h2)were selected as the converted species of methane from experimental *** mass fraction of C2 hydrocarbons and hydrogen as the product of the conversion reaction at the reactor was also *** values show good agreement with the actual experimental results in that the major conversion reaction occurred in C2h2 and hydrogen,and the conversions to C2h6,C2h4,and hydrogen were minor reactions of methane pyrolysis conversion.

关键词： numerical modelling non-transferred arc plasma methane chemical reaction

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

Fabrication of SAW Sensor for Detecting Chemical Agent

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稀有金属材料与工程 2006年第A03期35卷 433-435页

作者： J h.lee B S Joo J S huh D D lee School of Electronic & Electrical Engineering Kyungpook National UniversityKorea Dept.of Materials Science and Metallurgy Kyungpook National UniversityKorea

SAW sensors using five different types of polymer to detect of chemical agents(DMMP,Ch_3CN,Ch_2Cl_2,DCP) have been fabricated and its gas response characteristics were extensively *** polymers used as the sensing material are polyisobutylene(PIB),polyepichlorohydrin(PECh),polydimethylsiloxane(PDMS),polyisoprene(PIP)and polybutadiene(PBD).Their thin films were coated on quartz substrate by spin coating *** types of simulants gases,dimethylmethylphosphonate(DMMP),acetonitrile(Ch_3CN)and dichloromethane(Ch_2Cl_2),dichloropentane(DCP)were used as target gases,instead of the real nerve,blood,choking and vesicant *** spin coating of PIB and PECh,the substrates were heated to 65℃with N_2 flow for 1 h to remove the cyclohexane and ethylacetate which was used as solvent. PDMS was heated to 75℃with N_2 flow for 2 h to remove the ethylacetate which was used as *** and PIP on the substrate were heated to 60℃with N_2 flow for 1 h to remove the benzen which was used as *** sensing characteristics of the SAW sensors were measured by using E-5061A network analyzer.

关键词： SAW DMMP Ch3CN Ch2Cl2 DCP polymer film

Modeling and Design of h-Infinity Controller for Piezoelectric Actuator LIPCA

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Journal of Bionic Engineering 2010年第2期7卷 168-174页

作者： Gigun lee Kwanwoo You Taesam Kang Kwang Joon Yoon Jeong Oog lee Jung Keun Park Department of Aerospace Information Engineering Konkuk University

We proposed a dynamic model identification and design of an h-Infinity （i.e.h） controller using a LightweightPiezo-Composite Actuator （LIPCA）.A second-order dynamic model was obtained by using input and output data, and applyingan identification *** identified model coincides well with the real *** reduce the resonating mode that istypical of piezoelectric actuators, a notch filter was used.A feedback controller using the hcontrol scheme was designed basedon the identified dynamic model; thus, the LIPCA can be easily used as an actuator for biomemetic applications such as artificialmuscles or macro/micro positioning in *** control algorithm was implemented using a microprocessor, analogfilters, and power amplifying *** simulation and experimental results demonstrate that the proposed control algorithmworks well in real environment, providing robust performance and stability with uncertain disturbances.

关键词： piezoelectric actuator model identification h-infinity controller biomimetic artificial muscle LIPCA

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颗粒形状和表面因素对细粒方解石浮选的影响

国外非金属矿与宝石 1989年第3期 12-17页

作者： h.lee R.W.Smith 王力山东矿业学院

作者对粒度为0.1～40μm的人工和天然方解石进行了动电学研究和浮选试验。试验用物料的颗粒形状有明显的差别。人工矿样是用沉淀法从溶液中得到的,使用的浮选捕收剂为油酸钠和十四烷基硫酸钠。颗粒的形状及粒子的动电学特性对浮选效果... 详细信息

作者对粒度为0.1～40μm的人工和天然方解石进行了动电学研究和浮选试验。试验用物料的颗粒形状有明显的差别。人工矿样是用沉淀法从溶液中得到的,使用的浮选捕收剂为油酸钠和十四烷基硫酸钠。颗粒的形状及粒子的动电学特性对浮选效果的影响较小,天然矿样和人工矿样在浮选行为上存在一些微小的差异。尽管颗粒大小对其浮选过程具有一定的影响,然而,最重要的是如何使浮选矿浆产生明显的絮凝,以达到最好的浮选效果。（共6页)

关键词：方解石细粒浮选颗粒形状