• Title/Summary/Keyword: the left-handed

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Intermacromolecular Complex Formation between Helix Strilctilral Polypeptides through Hydrogen Bonding (수소 결합을 통한 Helix 폴리 펩타이드사이의 복합체 형성)

  • 조병기;김창규
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.18 no.1
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    • pp.99-132
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    • 1992
  • Polypeptide has been used broadly as an active ingredient in cosmetics We thought it is very important to investigate the adsorption behavior of polypeptide in order to pre-estimate the effect of these polypeptides. For the study of polypeptide adsorption, we have investigated complex formation of basic homopolypeptides, poly(L-proline) Form I [PLP(I)], Form II [PLP(II)] and poly(4-hydroxy-L-proline) (PHLP) with acidic homopolypeptides, poly(L-glutamic acid) (PLGA), poly(D-glutamic acid) (PDGA) and poly(L-aspartic acid) (PLAA) through hydrogen bonding in a hydroalcoholic medium with viscometer, 1ight scatter, pH meter and circular dicroism (CD). The polypeptides used in this study have helical structure in some conditions. The result exhibited that al 1 the complexes were formed as the composition of basic/acidic homopolypeptide : L:2 irrespective of the complex systems used. A more favorable complex is formed in the PLP(II)-PLGA system than PHLP-PLGA because PLP(II) has a more flexible helical conformation, whereas PHLP has a more rigid helical conformation. The right-handed helix PLGA formed the complex favorably and quickly with the left-handed helix PLP(II), whereas the left-handed helix PDGA formed the complex favorably with the right-handed helix PLP(I). The effect of side chain of the acidic homopolypeptides on the complexation was also studied. The result showed that more favorable condition for the complexation was PLGA-PLP(II) system which has longer side chain at acidic homopolypeptide than PLAA - PLP(II). All the above facts were well supported by CD measurement for the complex systems. By the CD spectra for the complexes we could deduce the conformational change of each homopolypeptide in the complexes On the basis of the above results, we performed the adsorption test of PLP(I, II) and PHLP on the hair having a left-handed helix. The adsorption amount of each polypeptide was analyzed by HPLC. The result showed that PLP(I) was adsorbed more than PLP(II), PLP(II) was adsorbed more than PHLP on the hair. On adsorbing polypeptides having a helical structure on the hair through hydrogen bonding, it could be concluded that the helical polypeptides having the opposite directional structure to the hair are adsorbed more than those having the same directional structure with the hair and also the polypeptides having a flexible conformation are adsorbed more than those having a rigid conformation.

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Metamaterial CRLH Structure-based Balun for Common-Mode Current Indicator

  • Kahng, Sungtek;Lee, Jinil;Kim, Koon-Tae;Kim, Hyeong-Seok
    • Journal of Electrical Engineering and Technology
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    • v.9 no.1
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    • pp.301-306
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    • 2014
  • We proposed a new PCB-type 'common-mode current($I_c$) and differential-mode current($I_d$) detector' working for fast detection of $I_c$ and $I_d$ from the differential-mode signaling, with miniaturization effect and possibility of cheaper fabrication. In order to realize this device, we suggest a branch-line-coupler balun having a composite right- and left-handed(CRLH) one-layer microstrip phase-shifting line as compact as roughly ${\lambda}_g/14$. The presented balun obviously is different from the conventional bent-&-folded delay lines or slits on the ground for coupling the lines on the top and bottom dielectrics. As we connect the suggested balun output ports of the differential-mode signal lines via the through-port named U and coupled-port named L, $I_c$ and $I_d$ will appear at port ${\Delta}$ and port ${\Sigma}$ of the present device, in order. The validity of the design scheme is verified by the circuit-and numerical electromagnetic analyses, and the dispersion curve proving the metamaterial characteristics of the geometry. Besides, the examples of the $I_c$ and $I_d$ indicator are observed as the even and odd modes in differential-mode signal feeding. Also, the proposed device is shown to be very compact, compared with the conventional structure.

Dual-Band Class F Power Amplifier using CRLH-TLs for Multi-Band Antenna System (다중밴드 안테나 시스템을 위한 CRLH 전송선로를 이용한 이중대역 Class F 전력증폭기)

  • Kim, Sun-Young;Seo, Chul-Hun
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.12
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    • pp.7-12
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    • 2008
  • In this paper, a highly efficiency power amplifier is presented for multi-band antenna system. The class F power amplifier operating in dual-band designed with one LDMOSFET. An operating frequency of power amplifier is 900 MHz and 2.14 GHz respectively Matching networks and harmonic control circuits of amplifier are designed by using the unit cell of composite right/left-handed(CRLH) transmission line(TL) realized with lumped elements. The CRLH TL can lead to metamaterial transmission line with the dual-band holing capability. The dual-band operation of the CRLH TL is achieved by the frequency offset and the nonlinear phase slope of the CRLH TL for the matching network of the power amplifier. Because the control of all harmonic components for high efficiency is very difficult, we have controled only the second- and third-harmonics to obtain the high efficiency with the CRLH TL. Also, the proposed power amplifier has been realized by using the harmonic control circuit for not only the output matching network, but also the input matching network for better efficiency.

The Measurement Camera System of Flight Data of Golfball for the Application of Screen Golf Contents (스크린 골프 콘텐츠 적용을 위한 골프공 비행 데이터 추출 카메라 시스템)

  • Kim, ki-hyun;Park, hyun-woo;Yoon, ji-han;Joo, woo-suk;Lee, dong-hoon;Yun, tae-soo
    • Proceedings of the Korea Contents Association Conference
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    • 2009.05a
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    • pp.875-879
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    • 2009
  • In this paper, we propose the measurement camera system of flight data of golfball for the application of screen golf contents. The existing flight data extraction system that applied on the screen golf content divided plate is dependent on it. in this paper, the camera system install in the ceiling that is able to look at passing golf ball. And left-handed and left-handed bats in the clear of the restrictions. Using high-speed CCD camera is shooting the ball flying. Acquired image is calculated from the coordinates. The location information of the calculated golf ball calculates a speed and a direction by using the physical formula, it applies the golf contents. After this system is useful sports type contents baseball, soccer, tennis.

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Frequency Tunable and Miniaturized Zeroth-Order Resonant(ZOR) Antenna Design by Metamaterial (메타 물질을 이용하여 소형화와 주파수 가변이 가능한 영차 공진 안테나)

  • Jang, Young-Soo;Choi, Jae-Hyurk;Lim, Sung-Joon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.8
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    • pp.900-904
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    • 2010
  • In this paper, a frequency tunable zeroth-order resonant(ZOR) antenna has been implemented. The ZOR characteristics of the proposed antenna is realized by using a composite right-and left-handed(CRLH) transmission line which consists of a rectangular slot on the ground plane of a mushroom structured antenna in order to minimize the antenna size. In addition, the tunable devices are introduced on the slotted ground plane for frequency tuning capability. Depending on the on and off states of the tunable device on the slotted ground plane, a shunt inductance value of the CRLH transmission line is changed and its resonant frequency becomes tunable. From the experimental results, the resonant frequency of the proposed antenna is changed from 4.92 GHz to 2.96 GHz. Additionally, the proposed antenna's size is reduced by 94.24 % compared with the half-wavelength patch antenna.

Improvement of the Radiation Efficiency for a CPW(Co-Planar Waveguide)-Fed ZOR(Zeroth-Order Resonant) Antenna (Co-Planar Waveguide(CPW) 급전 영차 공진 안테나의 방사효율 개선)

  • Cho, Tae-Joon;Lee, Hong-Min
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.1
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    • pp.59-66
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    • 2011
  • In this paper, a co-planar waveguide(CPW)-fed zeroth-order resonant(ZOR) antenna with an improved radiation efficiency was built and tested. The unit cell of the proposed antenna consists of a series metal-insulator-metal(MIM) capacitor and a shorted shunt stub inductor. In order to reduce the antenna size and to achieve the high radiation efficiency two shorted shunt stub arms bent by 90 degree were connected to the ground plane through the via. The proposed antenna consisting of two unit cells has an open ended composite right/left-handed(CRLH) transmission line structure. As a result the dominantly radiating parts of the antenna comes from shunt stub arms and vertical vias. The total size of the fabricated zeroth-order resonant antenna is $0.22\;{\lambda}_0{\times}0.22\;{\lambda}_0$. The measured gain and efficiency of the fabricated antenna have been enhanced by 3.07 dBi and 75 %, respectively, at the zeroth-order resonant frequency of 2.97 GHz.

Circularly Polarized Microstrip Antenna Using I-Shape Ground Slot Perturbation and Perpendicular Feeding Network (I-모양 슬롯 섭동과 수직한 급전구조를 이용한 원형 편파 마이크로스트립 안테나)

  • Shin, Yooncheol;Noh, Yoonsang;Lee, Min-Jae;Pyo, Seongmin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.6
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    • pp.497-500
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    • 2017
  • This paper proposes a circularly polarized microstrip antenna using an I-shape ground slot perturbation and a perpendicular feeding network. The proposed antenna consists of the symmetrical and perpendicular feeding and the microstrip square radiator loaded with the I-shape ground slot perturbation. The left-handed circular polarization(LHCP) formed by a 90-degree phase difference can be radiated by the perpendicular feeding network and the ground slot perturbation. An implemented antenna is designed for the use in the satellite communication system operated in S-band of 2.2 GHz, and is to be the 91 MHz of -10 dB bandwidth. The measured results of the antenna gain, far-field radiation pattern, and axial ratio agree well with the simulation results.

Modeling of Radiation Effects for 1-D RLH-TL Using Extraction of Circuit Parameters (회로 파라미터 추출을 통한 1-D RLH-TL의 방사 효과 분석)

  • Choi, Chang-Ho;Lee, Bom-Son
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.2
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    • pp.214-222
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    • 2008
  • The equivalent circuit for the RLH-TL is proposed considering radiation effects due to the inclusion of a series capacitor and shunt inductor in a unit cell for the right/left-handed transmission line(RLH-TL). The design equations to realize a specific phase shift at a given frequency is also provided. The S-parameters for unit cells with N=1, 3, 5, and 10 are analyzed in various aspects based on the EM and circuit simulations especially for the purpose of controlling radiation along RLH-TL's. A modification formula for the radiation rate per unit cell is also proposed for good agreement between the EM and circuit simulation results.

Design of a Micro-strip Patch Array Antenna using CRLH Transmission Line Power Divider Supporting Infinite Wavelength (무한파장 전파특성을 갖는 CRLH 전송선로 전력 분배기를 이용한 마이크로스트립 패치 배열 안테나의 설계)

  • Kim, Jung-hyung;Lee, Hong-min
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.3 no.2
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    • pp.39-45
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    • 2010
  • In this paper, an equally spaced $3{\times}2$ microstrip patch array antenna based on the fundamental infinite wavelength supported by the composite right/left-handed (CRLH) transmission line (TL) is proposed. The proposed CRLH TL unit cell consists of an inter-digit capacitor to realize left-handed (LH) series capacitance and non-symmetric shunt meander line with a shorted via to realize LH shunt inductance. At the infinite wavelength frequency of 2.09 GHz a 6-port series power divider consisting of a 19 unit cells shows a maximum magnitude difference of 0.73 dB and a $0.52^{\circ}$ maximum phase difference between output ports. The measured resonant frequency and maximum gain of the fabricated array antenna is 2.09 GHz and 10.98 dBi, respectively.

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Design of ZOR antenna for 2.45GHz WLAN using CRLH-TL (CRLH-TL을 이용한 2.45GHz 무선랜용 ZOR 안테나 설계)

  • Kim, Seung-Hwan;Yu, Jin-Ha;Lee, Young-Soon
    • Journal of Advanced Navigation Technology
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    • v.16 no.5
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    • pp.773-780
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    • 2012
  • ZOR(zeroth order resonance) antenna for 2.45GHz WLAN(wireless local area network) is designed by use of CRLH-TL(composite right left handed transmission line) meta-material. The electrical length of conventional antennas is determined generally according to the resonant frequency, whereas that of ZOR antenna can be determined without reference to the resonant frequency. Therefore ZOR antenna has advantage in miniaturization of antenna in comparison with conventional antennas. In order to design such ZOR antenna, first unit cell with electrical length shorter than a quarter wavelength at 2.45GHz is designed to the some characteristics of homogeneous medium. In order to decrease resonant frequency and enhance frequency bandwidth, the proposed antenna is fed by CPW(co-planar waveguide) and short stub between radiation patch and ground plane is used for obtaining both higher inductance and smaller capacitance than previous mush-room type of CRLH-TL.