• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.3
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• pp.257-267
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• 2015

This paper presents a ultra-wideband sinuous antenna that operates in a whole frequency range (0.824~5.85 GHz) of Cellular/GSM-800, GSM900, ISM, GPS, DCS/GSM1800, PCS/GSM1900, WCDMA/UMTS/IMT2000, WiBro, WLAN and WiMax. The proposed antenna, which is composed of two sinuous arms, is designed as a self-complementary structure in order to have frequency-independent characteristics. It also uses a wideband balun of Klopfenstein taper structure to match to $50{\Omega}$. Experimental results show that the -10 dB return loss bandwidth of the proposed antenna is 5.24 GHz that ranges from 0.76 to 6 GHz, which covers all the frequency bands of the various wireless services. Within the entire operating frequency range, the measured radiation patterns in both E-plane and H-plane show nearly constant bidirectional broadside beams and the maximum antenna gain is measured to fall between 2.32~6.01 dBi.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1414-1416
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• 2016

In this paper, a SWB (Super-WideBand) dipole antenna with self-complementary structure is proposed for signal intelligence. The proposed antenna consists of a self-complementary dipole antenna and a tapered balun for balanced feeding. The measured -10 dB reflection bandwidth of the proposed antenna is more than 28:1 (0.73-20 GHz) and 3 dB axial ratio bandwidth is 3.25:1 (1.91-6.22 GHz) with RHCP (Right Hand Circular Polarization) at +z direction. The measured radiation patterns are omni-directional in lower frequency band and bi-directional in higher frequency band. The measured peak gain within -10 dB reflection bandwidth varies from 2.83 dBi to 7.66 dBi.

• BMB Reports
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• v.31 no.1
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• pp.89-94
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• 1998

The structures of the self-complementary decamer duplexes, $d(ACGTATACGT)_2$ (TATA-duplex) and $d(ACGTTAACGT)_2$, (TTAA-duplex) has been obtained in solution by proton NMR spectroscopy and restrained molecular dynamics. The duplexes are essentially B-type, with distortions apparent at the TATA and TTAA steps. Theses distortions and their effects on dynamics have been investigated by the measurement of imino proton exchange time of the base-pairs. The unusual opening kinetics of central A T base-pairs could be correlated to the abnormal structural properties of the corresponding sequences.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.620-621
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• 2008

Transparent electronics has been one of the key terminologies forecasting the ubiquitous technology era. Several researchers have thus extensively developed transparent oxide-based thin-film transistors (TFTs) on glass and plastic substrates although in general high voltage operating devices have been mainly studied considering transparent display drivers. However, low voltage operating oxide TFTs with transparent electrodes are very necessary if we are aiming at logic circuit applications, for which transparent complementary or one-type channel inverters are required. The most effective and low power consuming inverter should be a form of complementary p-channel and n-channel transistors but real application of those complementary TFT inverters also requires electrical- and even photo-stabilities. Since p-type oxide TFTs have not been developed yet, we previously adopted organic pentacene TFTs for the p-channel while ZnO TFTs were chosen for n-channel on sputter-deposited $AlO_x$ film. As a result, decent inverting behavior was achieved but some electrical gate instability was unavoidable at the ZnO/$AlO_x$ channel interface. Here, considering such gate instability issues we have designed a unique transparent complementary TFT (CTFTs) inverter structure with top n-ZnO channel and bottom p-pentacene channel based on 12 nm-thin nano-oxide/self assembled monolayer laminated dielectric, which has a large dielectric strength comparable to that of thin film amorphous $Al_2O_3$. Our transparent CTFT inverter well operate under 3 V, demonstrating a maximum voltage gain of ~20, good electrical and even photoelectric stabilities. The device transmittance was over 60 % and this type of transparent inverter has never been reported, to the best of our limited knowledge.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.2
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• pp.374-382
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• 2017

This paper proposed a 2 stages 2-arm sinuous antenna that operates in frequency range 0.8-6GHz. The proposed antenna's total radius is 60mm, in which 1st stage's radius is 50mm which is designed as self-complementary structure(cell's angle width $90^{\circ}$) with 8 cell, and 2nd stage is composed of non-self-complementary structure with 0.5 cell of cell's angle width $720^{\circ}$ in the radius width 10mm. Measurement's result shows that -10dB return loss starts at 0.807GHz, but 1 stage 2-arm sinuous antenna that use the same radius starts at about 0.878GHz, so proposed the possibility of the miniaturization of the sinuous antenna.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.6
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• pp.612-620
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• 2008

In this parer, parabolic edge planar monopole antenna for UWB communication is presented. The antenna have broadband property structurally through planar monopole and ground which have parabolic edge. It is designed close to self-complementary structure as changing curvature of edge of monopole and ground. Monopole and ground of proposed antenna exist on coplanar plane, and excite as coaxial feeding. It used FR4 dielectric substrate of ${\varepsilon}_r=4.4$, and the size is $26{\times}31{\times}1.6mm$. Return loss is more than 10 dB in $3.1{\sim}10.6GHz$. Radiation pattern is about the same that of dipole antenna at all frequency. At measured result, max gain is $1.37{\sim}6.02dBi$ at E-plane.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.11
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• pp.1225-1232
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• 2009

In this paper, a parabolic edge planar monopole antenna for indoor DTV reception is presented. The antenna has broadband property with the planar monopole and ground of parabolic edges. It is designed close to self-complementary structure as changing curvature of edges of monopole and ground. Monopole and ground conductors of the antenna are on the same plane, and excited through CPW feeding. It is fabricated on an FR4 dielectric substrate of $\varepsilon_r=4.4$, and the dimension is $40\;mm{\times}200\;mm{\times}1.6\;mm$. Return loss is larger than 10 dB in 470~806 MHz. Maximum gain is 1.86 dBi on E-plane at 810 MHz and 3.86 dBi on H-plane at 600 MHz.

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2684-2688
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• 2014

Two two-dimensional cyanide- and phenoxo-bridged heterometallic M(II)-Mn(III) (M = Ni, Pd) coordination polymers $\{[Mn(saltmen)]_4[Ni(CN)_4]\}(ClO_4)_2{\cdot}CH_3OH{\cdot}H_2O$ (1) and $\{[Mn(saltmen)]_4[Pd(CN)_4]\}(ClO_4)_2{\cdot}CH_3CN{\cdot}H_2O$ (2) ($saltmen^{2-}$ = N,N'-(1,1,2,2-tetramethylethylene)bis(salicylideneaminato)dianion) have been obtained by using $K_2[M(CN)_4]$ as building blocks and a salen-tpye Schiff-base manganese(III) compound as assembling segment. Single X-ray analysis reveals their isostrutural cyanide-bridged $MMn_4$ pentanuclear cationic structure. The four Schiff base manganese units of the pentanuclear entity are self-complementary through the phenoxo oxygen atoms from the neighboring complex, therefore forming cyanide- and phenoxo-bridged 2D sheet-like structure. Investigation over magnetic susceptibilities reveals the overall ferromagnetic coupling between the adjacent Mn(III) ions bridged by the phenoxo oxygen atoms with J = 2.13 and $2.21cm^{-1}$ for complexes 1 and 2, respectively.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2906-2910
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• 2011

A fluorescent nucleoside analogue, $^AC$, featuring two non-complementary nucleobases linked through an ethynyl group, was synthesized. The extended ${\pi}$-conjugation imparts $^AC$ with red-shifted absorbance (relative to adenine and cytosine) and pale-blue fluorescence. It spontaneously forms nanoparticles, which exhibit considerably enhanced fluorescence, without the help of any additional stabilizing agent. The DMSO/water ratio was an important factor influencing the construction of the NPs. X-ray crystallography confirmed the structure of $^AC$; dynamic light scattering and scanning electron microscopy confirmed the existence of the nanoparticles.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1273-1274
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• 2015

본 논문에서는 주파수 무관(frequency independence) 특성을 갖는 자기상보 구조(self-complementary structure)로 된 안테나의 급전선로(feed line)로 사용할 수 있는 초광대역 발룬(ultra-wideband balun)을 제안하였다. 발룬을 설계하기 위해 클로펜스타인 테이퍼(Klopfenstein taper)를 사용하여 임피던스 프로파일(impedance profile)을 구하고 이를 평행 스트립 선로(parallel strip line) 구조로 구현하기 위해 등각사상방법(conformal mapping method)을 이용했다. 설계한 발룬을 직접 제작하여 측정한 결과, 대역폭은 반사손실 -10 dB를 기준으로 할 때 0.45~10.53 GHz까지 10.08 GHz로 나타나, UHF(ultra high frequency) 통신대역에서 UWB(ultra-wideband) 통신대역에 이르기까지 매우 넓은 주파수 범위에서 자기상보형 안테나의 입력 임피던스 $188{\Omega}$을 $50{\Omega}$의 특성 임피던스에 정합시킬 수 있음을 확인하였다.