• 조명전기설비학회논문지
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• 제18권4호
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• pp.155-159
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• 2004

본 논문은 마이크로 스트립 라인을 무선 랜(IEEE 802.11a, IEEE 802.11b, IEEE 802.llg)에 사용할 수 있는 SPDT FET 스위치를 설계하고 시뮬레이션 하였다. 특히 주파수에 따른 능동소자의 영향을 최소화하기 위하여 임피던스 변환회로를 적용하여 설계하였다. 이 SPDT스위치 수신경로의 삽입손실은 2(㎓)에서 4(㎓)까지 0.8(㏈)에서 1.462(㏈)를 나타내고 있으며, 4.7(㎓)에서 6.7(㎓)까지 1.26(㏈)에서 2.3(㏈)을 보이고, 격리도는 2[㎓)에서 6.7(㎓)의 대역에서 30(㏈)이하를 나타낸다. 그리고 송신경로에서의 삽입손실은 2(㎓)에서 4(㎓)까지 1.18(㏈)에서 2.87(㏈)를 나타내고 있으며, 4.7(㎓)에서 6.7(㎓)까지 0.625(㏈)에서 1.2(㏈)을 나타내고 있다. 격리도는 2(㎓)에서 6.7(㎓)의 대역에서 30(㏈)이하를 나타낸다

• Journal of Plant Biology
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• 제15권2호
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• pp.20-23
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• 1972

The isolations of fungi were observed, the isolations which were of rotting apples, pears, pine-seeds and dates cultivated in Korea, while they were living upon them. As a result of such observation. Penicillium sp. which rotted apples and pears could be isolated from the apples and pears. When the Penicillium sp. was inoculated into some fresh apples and pears, they were all rotted away. This fungus was identified as Penicillium expansum. Some fresh apples and pears inoculated with a mass of mycelium and conidia of P. janthinellun or some others inoculated with those of P. frequentans were not rotted. Though the P. expansum has been known to us a destructive not of pomaceous fruits, this fungus strain also caused the putrefaction of pears. It was found that P. expansum could be properly grown up at the temperature of $25^{\circ}C$ and pH 3~5 of media.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.170-177
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• 2004

A single degree of freedom system and transmissibility are key concepts in many problems of vibration isolation. In order to apply this approach, however, several assumptions must be satisfied, which are often not realistic. In this paper, an approach using vibration power flow is introduced to deal with vibration isolations in a more practical way. Procedures of this approach and some results of research are presented. Difficulties in this method are also discussed.

• 대한수의사회지
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• 제9권2호
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• pp.3-22
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• 1965

In 1908, Toxoplasma was demonstrated for the first time by Nicolle. Since then a number of isolations from birds and other mammalians including human were reported by many workers. Each strain of Toxoplasma isolated from various animals was identified as

• 한국전기전자재료학회논문지
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• 제25권12호
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• pp.949-954
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• 2012

The K-PCS and W-CDMA dual band dielectric duplexer and bandpass filters have been designed and fabricated. The dual band duplexer consists of the separate monoblock K-PCS and W-CDMA duplexers using common antenna port. The coupling capacitance and I/O impedance matching have been designed to minimize the cross interference between the bands. Isolations of crosspoint between Tx and Rx in K-PCS and W-CDMA dualband were about 47 dB and 100 dB, respectively. On the other hand, isolations of Tx and Rx in K-PCS and W-CDMA were about 66 dB and 65 dB, respectively. The difference between 47 dB and 100 dB originated from the different center frequencies in Tx and Rx of K-PCS and W-CDMA bands. The coupling capacitance of the bandwidth, I/O capacitance of I/O matching and impedance matching, and various capacitances were important role to fabricate the dielectric duplexer and bandpass filters.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1509_1510
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• 2009

This paper presents the design and simulation results of ohmic contact RF MEMS silicon switch with a high isolation at high frequencies along with the position of a contact part, initial off-state and intermediate off-state including the state where a contact part is placed right over a signal line of coplanar waveguide (CPW). The ohmic contact part is connected with comb drives made of high resistivity single crystalline silicon. The released contact part is $30{\mu}m$ apart from the edge of signal line on the glass substrate along the lateral direction (x-direction) at initial off-state. The electrostatic force of the comb electrode creates the x-directional movement thus initial state is converted to the intermediate off-state. The initial off-state of the switch results in isolations of -31 dB, -24 dB and reflections of -0.45 dB, -0.67 dB at 50 GHz and 110 GHz, respectively. It shows the isolation degradation when the contact part moves right over the signal line of CPW like an initial off-state of a conventional MEMS switch. The isolations and reflections are -31 dB, -24 dB and -0.50 dB, -1.31 dB at 50 GHz and 110 GHz, respectively at the intermediate off-state.

• 한국통신학회논문지
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• 제28권3A호
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• pp.179-184
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• 2003

본 논문에서는 ISM대역에서 수신경로의 격리도를 크게 송신경로의 삽입손실은 작게 하며 동시에 P1dB를 크게 하는 비대칭구조의 MMIC SPDT 스위치를 제안하였으며, 이를 ETRI에서 지원하는 IDEC MPW의 0.5㎛ GaAs MESFET으로 제작하였다. 이 SPDT 스위치 수신경로의 삽입손실은 3GHz에서 1.518dB, 5.75GHz에서 1.777dB이고, 격리도는 3GHz에서 38.474dB, 5.75GHz에서 29.125dB로 측정되었다. 그리고, 송신경로의 삽입손실은 3GHz에서 0.961dB, 5.75GHz에서 1.162dB이고, 격리도는 3GHz에서 23.259dB, 5.75GHz에서 16.632dB였다. 비대칭구조의 스위치는 대칭구조에 비하여 수신경로의 격리도가 3GHz에서 15.9dB, 5.75GHz에서 11.9dB 정도 개선되었으며, 삽입손실은 약 0.6dB 정도 증가하였다. 또한, SPDT 스위치 송신경로의 P1dB는 21.5dBm로 대칭구조에 비하여3.86dB 증가하였다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring
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• pp.383-390
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• 2000

The purpose of this paper is to investigate dynamic characteristics of an isolated bridge with a different location of seismic isolation at piers and to determine the best location of seismic isolation. The substructure of the bridge is two column framed type reinforced concrete and has relatively high piers so it has long natural period, To decide the best location of seismic isolations displacement shear force bending moment acceleration and absorbed energy are compared using fast nonlinear analysis. To isolate overall structures is effective to bending moments and shear forces for long period bridges.

• Mycobiology
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• 제28권1호
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• pp.1-4
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• 2000

The section of Annulata under genus Hypoxylon is a member of the Xylariaceae which has ascomata with ostioles papillate ill a flattened disc. The isolates of Hypoxylon collected from the Tropic to the Temperate are compared with similar taxa and described. These isolations under Annulata section are illustrated with a light microscopy and a scanning electron microscopy. Hypoxylon archeri is newly recorded from Korea. A key to the species is also included.

• Mycobiology
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• 제28권1호
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• pp.5-10
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• 2000

The genus Hypoxylon is a member of the Xylariaceae which has brown to dark brown and pha- seoliform single cell ascospores with a conspicuous full germ slit. The isolates of Hypoxylon collected from England, Hong Kong and Korea are compared with similar taxa and described. These isolations under Hypoxylon section are detailed and illustrated, using light microscopy and scanning electron microscopy. Hypoxylon howeianum and H. rubiginosum are described and compared with former collection from Korea. A key to the species is also included.