• Korean journal of applied entomology
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• v.48 no.4
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• pp.553-556
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• 2009

We surveyed natural enemies of Pachynematus itoi Okutani, newly recorded sawfly pest of Larix leptolepis, and investigated their occurrence and life cycle at Cheolwon and Taebaek, Gangwon Province in 2006~2007. Endasys liaoningensis was identified as main natural enemy of P. itoi Okutani. Parasitism of E. liaoningensiswas was 42%. Emergence period of E. liaoningensis was from May to September, and the peak of emergence was from 21th May to 20th June. It was suggested that the occurrence number and period of E. liaoningensis were quite closely relative to those of host, P. itoi.

• Journal of the korean veterinary medical association
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• v.28 no.6
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• pp.321-329
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• 1992

'주' 필자는 최근(1992년 3월 5일$\~$30일)에, 한일공동 연구사업 수행을 위하여 일본정부 과학기술청의 <개별 전문가 초청계획>에 의한 초청을 받아 일본 농림수산성 가축위생시험장을 다녀왔다. 본래, 일본에 가게된 주 목적은 '소 타일레리아병에 관한 병원학적 비교연구'이었으며, 진드기 체내 및 우체내에 있어서의 타일레리아 원충의 발육단계별 정밀진단과 정제백신 개발을 위한 생물공학적 기술응용 연구가 주요 과제내용이었다. 마침, 제 113회 일본 수의학회 학술대회(1992년 4월 2일$\~$4일)의 개최가 예정되어 있었고, 이 학회의 <기생충학 분과회 심포지움>의 주제가 '톱밥 축사에 있어서의 새로운 선충성 질병'이었으며, 그 심포지움의 대장으로 예정되어 있는 평 조형 박사(일본 농림수산성 가축위생시험장 기생충연구실 실장)및 공동연구자 중촌의남 박사 등과 접촉하여 연구실 견학 및 토의를 할 수 있는 기회를 가진 바 있으며(사진 참조), 관련된 최신문헌을 입수한 바 있다. 본 편에서는, 최근에 일본에서 새로운 기생충성 질병으로 문제시 되고 있는 '송아지 돌연사'와 관련하여, 그 병원체인 유두분선충(Strongyloides papilosus)의 감염피해 실태와 인공감염시험 결과 등에 대하여 금년도 일본수의학회 기생충학 분과회 심포지움 주제발표 내용을 중심으로 하여 해설을 드리고 한편, 유두분선충증의 병원체 및 생활환모형, 감염역학과 감염성립조건, 진단 및 치료대책, 향후 연구문제와 전망 등에 대하여 함께 고찰해 보고자 한다.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.3
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• pp.173-173
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• 2004

In this paper, a wideband two-layer H-shaped microstrip antenna for WLAN is designed. To increase the bandwidth of microstrip patch antenna a configuration of stacked type using parastic element is used. Furthermore, to reduce the size of microstrip patch antenna, two techniques are employed . the first one is H-shaped patch type and the second one is that the main radiator and parastic patch are shorted to the ground plane using ten shorting posts. The antenna bandwidth and radiation characteristics are calculated by ENSEMBLE ver. 5.0 simulation software, and compared with the experimental results. Experiment results show that the bandwidth of antenna in 740㎒ centered at 5.46㎓(13.5%), which is close agreement with the calculations, 770㎒(13%). Also, the antenna size can be reduced by 71.5% compared with the half wavelength rectangular microstrip antenna using the same substrate at the same frequency.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.39 no.11
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• pp.40-46
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• 2002

A MEMS(Micro Electro Mechanical System) package using a doped-silicon(Si) carrier for coplanar microwave and millimeter-wave integrated circuits is proposed in order to reduce parasitic problems of leakage, coupling and resonance. The proposed carrier scheme is verified by fabrication and measuring a GaAs CPW(Coplanar Waveguide) on the three types of Si-carriers(gold-plated high resistivity, lightly doped, high resistivity). The proposed MEMS package using the lightly doped(15 ${\Omega}{\cdot}$) Si-carrier shows parasitic-free performance since the lossy Si-carrier effectively absorbs and suppresses the resonant leakage.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.55-59
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• 2013

A new method using RF Ids determined from measured S-parameters is proposed to extract the gate-voltage dependent effective carrier velocity of bulk MOSFETs in the saturation region without additional dc Ids measurement data suffering parasitic resistance effect that becomes larger with continuous down-scaling to sub-$0.1{\mu}m$. This method also allows us to extract the carrier velocity in the saturation region without the difficult extraction of bias-dependent parasitic gate-source capacitance and effective channel length. Using the RF technique, the electron velocity overshoot exceeding the bulk saturation velocity is observed in bulk N-MOSFETs with a polysilicon gate length of $0.065{\mu}m$.

• Journal of fish pathology
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• v.17 no.2
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• pp.99-103
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• 2004

White spot disease by Cryptocaryon irritans broke out among cultured river puffer (Takifugu obscurus) cultured in sea water in Oct. 2001 and May 2004. Many white spots were easily observed on the gills with the naked eyes. The parasites attached on the gills at the base of the gill lamellae. The trophonts penetrated the interlamellar epithelium. Epithelial cell proliferation in interlamellar spaces occurred. PAS- positive mucous cells were prominent in the proliferated epithelium.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.6
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• pp.528-537
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• 2002

In this paper, the extended FDTD is used for the analysis of microwave circuits including active elements. Lumped elements such as R, L, C which are inserted into a microstrip line are analyzed with the FDTD lumped element modeling. Parasitic capacitance and inductance could be obtained using network modeling and so it is sure that FDTD lumped element modeling makes it possible to get more accurate data which include parasite components. Moreover, a balanced mixer using two diodes that are modeled by an extended FDTD is designed and the more exact characteristic of the mixer is acquired than in current circuit simulator.

• Korean journal of applied entomology
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• v.17 no.1 s.34
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• pp.65-69
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• 1978

An intensive survey of rice insect pests and their natural enemies with special references on parasites of rice stem-borers was made during the last 5 years(1973-77). The results were obtained as follows: 1. 15 species of hymenopterous parasites from the rice stem-borers were identified; Trichogrammatidae-2 spp, Scelionidae-1 sp, Braconidae-5 spp, Ichneumonidae-7spp. 2. The two Trichogrammatids species, Apanteles chilonis and Microgaster russata are first records from Korea. 3. Museum presence specimens of the 3 species: Trichogramma chilonis, Eriborus terebrans and Gombrus ruficoxatus, we previously identified in Korea, could not be located in this periods of study.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11B
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• pp.1620-1627
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• 2001

In this paper, a broadband microstrip antenna for PCS and IMT-2000 service is designed. To obtain the broadband characteristics of an antenna, we utilized the multi-layered structure composed of two foam material layers, parasitic element and aperture coupled feeding network. The broadband characteristic is obtained by changing the size of parasitic element and the height of foam materials. In addition to that, the usage of metal layer at the distance of λ/4 from feed-line, back radiation is reduced. The bandwidth of a single element for VSWR less than 1.3 is about 550MHz. The bandwidth of a designed 1$\times$4 array antenna for VSWR less than 1.3 is about 460MHz. The gain of a designed array antenna is about 11.15∼12.15dBi and the front-to-back ratio is about 30dB.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.102-110
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• 1985

In order to determine the epidemiological pattern of the Paragonimus westermani, the infestation rates for the cercarial and metacer-carial larvae of digenetic trematodes in the snail and crayfish hosts, and the prevalence of Paragonimus westermani among the residents in the vicinity of the stream Namdae, Wyangpi, and Kwang, in the Ulchin county, Kyungpook Province were studied from March to October in 1984. The population density of the snails per square meter of the habitats ranged from 5 to 25, with an average of 15. Among the seven habitats, one, Ducheon, had snails infested with the cercariae of Paragonimus westermani, and the proportion of infested snails was very low, the average being 0.152 per thousand. Of six hundred and four crayfish examined, 113 or 18.7 per cent harboured the encysted larvae of Paragonimus westermani. A high infestation rate for the metacercariae in the crayfish was found in two habitats; 39.0 per cent in the Ducheon and 21. 6 per cent m the Sokwang. The prevalence of Paragonimus westermani among the residents in Ulchin county was relatively high, 25.8 per cent by the Paragonimus intradermal tests, and the difference in the rate of infection between males and females was found to be significant (t>2). The results obtained in this study indicate that endemic foci of Paragonimus westermani exist in Ulchin county and the prevalence of this lung fluke among the residents is relatively high.