• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1214-1217
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• 2004

현재 전기용량의 국가표준은 1 kHz, 1592 Hz에서만 유지 및 보급이 되고 있다. 그러나 전기용량 및 임피던스를 측정하는 브리지와 LCR meter들은 비교적 넓은 주파수 범위에서 측정이 가능하도록 생산이 되고 있다. 따라서 이러한 기기들의 교정은 실제적으로 사용되고 있는 주파수 전 영역이 아닌 1 kHz 만 되고 있어서 완전한 교정이라고 할 수 없다. 본 논문에서는 이를 해결하기위하여 임피던스 analyzer의 one-port 측정기술을 사용하여 4-terminal-pair(이하 4TP) 전기용량 표준기 각각의 terminal에서 임피던스를 필요 주파수에서 측정하고, 측정된 임피던스 matrix를 이용하여 4TP의 transfer 어드미턴스와 출력임피던스를 계산 하였다.

• Korean Journal of Plant Resources
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• v.30 no.6
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• pp.654-661
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• 2017

Dual-color fluorescence in situ hybridization karyotype analysis was created using repetitive sequences including two types of rDNA repeats (45S and 5S rDNAs) and Arabidopsis-type telomere sequence repeats. The somatic metaphase cells of Carthamus tinctorius were observed as diploids (2n=2x=24). A symmetrical or slightly asymmetrical karyotype with seven pairs of metacentric and five pairs of submetacentric chromosomes was observed. The lengths of the somatic metaphase chromosomes ranged from 4.18 to $6.53{\mu}m$, with a total length of $60.71{\mu}m$. One locus of 45S rDNA was located on the pericentromeric regions of three pairs of chromosomes and the other pair was situated on the terminal regions of the short arms of a single pair of chromosomes. One locus of 5S rDNA was detected on the interstitial regions of the short arms of two pairs of chromosomes. Arabidopsis-type telomeric repeats were detected on the terminal regions of all pairs of chromosomes. Co-localization of loci between telomeric repeats and 45S rDNA was observed in a single pair of chromosomes. The results provide additional information for the existing physical mapping project of C. tinctorius and will also serve as a benchmark to a more intricate cytogenetic investigation of C. tinctorius and its related species.

• Journal of Applied Reliability
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• v.8 no.4
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• pp.181-192
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• 2008

In this paper, we proposed effective algorithm that do Availability of communication network account using total probability formula. Use path tracing method about PSTN linked with MSC in WCDMA considering occasion that do not consider mobility of terminal and Availability did account. First, express minimum path series gathering by structure function after network that do modeling by stochastic graph for communication network saves all minimal path sets between particular two abutments and we gain Availability value in angular variable after express structure function by Boolean operation form and Availability between two abutments did account.

• Journal of the Korean Institute of Telematics and Electronics
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• v.19 no.6
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• pp.1-8
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• 1982

In this paper a new analytic method for Ladder networks by weighted tree is proposed. In contrast to conventional tree concept that represents only information structure, in this paper, a tree with hierarchical structure is established by giving wei체t of impedance Z and admittance Y to branch and representing each node of its branch as a pair of voltage and current. Then, by defining generation level from tree structure and by parsing between standand level and arbitrary level, driving point impedance, transfer function and transfer impedance are simultaneously obtained instead of complex calculation method by inspection. The validity of this method is proved by the reciprocal theorem and this method is applied to four-terminal constants and the feedback network.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.109-122
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• 2002

The standard capacitor must have not only precise value of the capacitance but also the basic properties of low dielectric loss tangent. In the reforming process of capacitors, the dielectric loss tangent must be also reformed. In this paper, the development of standard capacitors of 10 and 100pF for the dielectric loss tangent standard using $Al_{2}O_{3}$ Crystal and the measurement of dielectric loss tangent are discussed. The dielectric loss tangent depends upon the surface between electrode and dielectric in capacitor. With using the Electric Field Simulator, precise design values of electrode are simulated. For the purpose of measuring capacitance effect just in the dielectric, 3-Terminal and 4-Terminal Pair configuration are applied respectively at the electrode and the connector for the measuring equipment. As stated above method, the standard capacitors of 10 and l00pF for the establishment of the dielectric loss tangent standard using the $Al_{2}O_{3}$ Crystal are made with low dielectric loss tangent less than 10-4.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4A
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• pp.408-416
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• 2010

A dumbbell-type CPW transmission-line structure has been proposed to improve the return loss of the transmission line between a driver IC and flip-chip-bonding VCSEL(Vertical Cavity Surface Emitting Laser) in a hybrid opto-electric circuit board(OECB). The proposed structure used a pair of dummy ground solder balls on the ground lines for flip-chip bonding of the VCSEL and designed the dumbbell-type CPW transmission line to improve reflection characteristics. The simulated results revealed that the return loss of the dumbbell-type CPW transmission line was 13-dB lower than the conventional CPW transmission line. A 4-dB improvement in the return loss was obtained using the dummy ground solder balls on the ground lines. The variation rate of the reflection characteristic with the variation of terminal impedances of the transmission line (at the output terminal of the driver IC and the input terminal of the VCSEL) is about ${\pm}2.5\;dB$.

• Bulletin of the Korean Chemical Society
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• v.12 no.1
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• pp.17-22
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• 1991

Fourier transform infrared spectroscopy has been applied to the characterization of titania supported molybdena. The equilibrium adsorption method seemed to produce molybdena species homogeneously dispersed on the support. Even under an oxidizing environment, molybdena species appeared to be able to possess coordinatively unsaturated $Mo^{5+}$ ions owing to the natures of TiO$_2$, i.e. oxygen deficiency and permeability toward oxygen diffusion. At the initial stage of reduction, the terminal double bond oxygen ( Mo=O ) seemed to be removed, generating presumably $Mo^{4+}$. The carbonyl bands at 2198 and 2190 $cm^{-1}$ observed after CO exposure were attributed to the $Mo^{5+}{\cdots}CO\;and\;Mo^{4+}\;{\cdots}CO$ complexes, respectively, while the band pair at 2136 and 2076 $cm^{-1}$ to $Mo^{4+}(CO)_2$.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.7-11
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• 2003

Karyotype analysis and chromosomal localization of 5S and 45S rDNAs using FISH (fluorescence in situ hybridization) technique were carried out in Nicotiana plumbaginifolia. Somatic chromosome number of N. plumbaginifolia was 2n=20 and kyarotype was composed of three pairs of metacentric chromosomes (1,2 and 7) and seven pairs of submetacentric chromosomes (3, 4, 5, 6, 8, 9 and 10). Length of chromosomes was ranged from 2.29 to 4.50 ${\mu}{\textrm}{m}$. Chromosome 1 and 2 were identified as satellite chromosomes. In FISH experiment, one pair of 5S rDNA signals was detected on the centromeric region of chromosome 2 and one pair of 45S rDNA signals was detected on the terminal region of chromosome 1.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.374-383
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• 2013

This paper presents a design for improvement of isolation characteristics by the inserted stub structure on ground plane of a handy terminal which is composed of a main antenna and a sub antenna covered LTE bandwidth. In order to compensate for a resonance length of proposed antenna and to realize a high isolation characteristic, a pair of stub was inserted and located on ground plane that currents from two antennas were converged. A simulated isolation characteristic of antenna without stub at the LTE class 13 band was about -5 dB, but its characteristics of proposed antenna with two stubs at uplink(777~787 MHz) and downlink(746~756 MHz) of the LTE class 13 band were about -12 dB and -15 dB, respectively. An average gain of a fabricated antenna with two stubs was observed about -2 dBi above and it showed good results with comparison of business condition that the average gain of commercial handy terminal has to appear -4 dBi above. The measured S-parameter characteristics and radiation patterns showed a reasonable agreement with the simulation results.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.3
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• pp.61-72
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• 2002

In this paper, we propose two timing-driven routing algorithms for single-source net and multi-source net as applications of 1-Steiner heuristic algorithm. Using the method of substituting the cost of 1-Steiner heuristic algorithms with interconnection delay, our routing algorithms can route both single-source net and multi-source net which have all critical source-terminal pairs or one critical pair efficiently Our single-source net routing algorithm reduced the average maximum interconnection delay by up to 2.1% as compared with previous single-source routing algorithm, SERT, and 10.6% as compared with SERT-C. and Our multi-source net routing algorithm increased the average maximum interconnection delay by up to 2.7% as compared with MCMD A-tree, but outperforms it by up to average 1.4% when the signal net has only subset of critical node pairs.