• Korean Journal of Environment and Ecology
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• v.31 no.3
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• pp.287-296
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• 2017

In order to check host plant diversity and to confirm the potential risk to be invaded, we documented host plant flora and plant part of C. pentagona, an invasive parasitic plant in field survey and induced parasitic infection by them in the laboratory experiment. Parasitic interaction(12% of total tree species) was found in twig and leaf of tree such as Quercus mongolica and Abies holophylla that was not developed into ligninfication. There were most host plant species belong to Compositae, but the species parasitic rate of family was higher in Cyperaceae, Polygonaceae and Leguminoceae. Through the inducible infection experiment with C. pentagona, all species except one species show parasitic interaction between host plan and C. pentagona. These result means that the limiting stage for invading area is dispersion process for invading other area in Korea. Infection plant part by C. pentagona was dominantly both shoot and leaf, rather than only leaf or only shoot. We found newly 12 families and 45 host plant species including 33 herbacious one and 12 woody one. Crop plant such as Setaria italica and 6 endangerd one such as Scrophularia takesimensis, especially the later rare endemic plant was to death by parasitic infection of C. pentagona. These results indicate that C. pentagona is potential risk to both wild and cultivated plant in Korea.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.10
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• pp.33-46
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• 2015

In this paper, we predicts the analog and digital circuit performance of FinFETs that are scaled down following the ITRS(International technology roadmap for semiconductors). For accurate prediction of the circuit performance of scaled down devices, accurate parasitic resistance and capacitance analytical models are developed and their accuracies are within 2 % compared to 3D TCAD simulation results. The parasitic capacitance models are developed using conformal mapping, and the parasitic resistance models are enhanced to include the fin extension length($L_{ext}$) with respect to the default parasitic resistance model of BSIM-CMG. A new algorithm is developed to fit the DC characteristics of BSIM-CMG to the reference DC data. The proposed capacitance and resistance models are implemented inside BSIM-CMG to replace the default parasitic model, and SPICE simulations are performed to predict circuit performances such as $f_T$, $f_{MAX}$, ring oscillators and common source amplifier. Using the proposed parasitic capacitance and resistance model, the device and circuit performances are quantitatively predicted down to 5 nm FinFET transistors. As the FinFET technology scales, due to the improvement in both DC characteristics and the parasitic elements, the circuit performance will improve.

• Korean journal of applied entomology
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• v.21 no.2 s.51
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• pp.87-94
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• 1982

The mymarids egg parasite of rice planthopper, Anagrus nr. flaveolus, were investigated to know their parasitic activities after overwitering in the paddy banks and barley fields, their host preferences and seasonal variations in the pesticide sprayed and unsprayed paddy fields of Gyeongnam province O.R.D. at Jinju from 1977 to 1979. The parasitic activities of Anagrus nr. flaveolus after overwintering in the paddy banks were high early in April and tended to decrease remarkably since mid-April by moving to the barley fields. The parasitic rate of Anagrus nr. flavelous was $47.2\~88\%$ between middle and late in April, the peak of egg deposition period. Anagrus nr. flaveolus parasitized Laodelphax striatellus, Nilaparvata lugens, and Sogatella furcifera, but didn't attack the eggs of Nephotettix cincticeps in the paddy fields. High preference was observed with Laodelphax steriatellus. The parasitic activities of Anagrus nr. flaveolus in the pesticide sprayed paddy fields were high in early July and from late August to early September. The parasitic rate in the pesticide unsprayed fields were higher than those of sprayed fields during the pesticide spraying period, from July to August and parasitic activities were active from October to before coming winter.

• Journal of agricultural medicine and community health
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• v.27 no.2
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• pp.67-73
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• 2002

집쥐가 인체 기생충 전파에 어느 정도의 역할을 하는지 그 양상을 밝히고자 전라북도 남원, 익산지역에서 포획한 집쥐의 체내 기생충 감염상을 조사하였다. 섬진강 상류 남원지역에서 32마리, 만경강 중류 익산지역에서 53마리를 채집하여 총 85마리였고, 종별로는 곰쥐(Rattus rattus) 28마리, 시궁쥐(Rattus norvegicus) 57마리였다. 결과를 요약하면 다음과 같다. 1. 남원, 익산지역의 집쥐 85마리 중 71마리(83.5%)에서 체내 기생충이 검출되었다. 2. 폐장이 회수되었던 집쥐 74마리 중 35마리(47.3%)에서 폐장에 기생하는 조직 기생충인 폐포자충(Pneumocystis carinii)이 검출되었다. 3. 전체 85마리의 가로막에서 선모충(Trichinella spiralis)을 조사하였고, 폐심장 혈관계에서 광동주혈선충(Angiostrongylus cantonensis)을 조사하였으나 한 예도 검출하지 못하였다. 4. 간을 조사한 바 85마리 중 간모세선충(Capillaria hepatica) 22례(25.9%), Taenia taeniaeformis의 유충(Cysticercus fasciolaris) 9례(10.6%), 간흡충(Clonorchis sinensis) 1례(1.2%)가 검출되었다. 5. 장내용물을 조사 한 바 85 마리 중 50례(58.9%)에서 윤충 및 원충이 검출되었다. 윤충은 쥐조충(Hymenolepis diminuta), 극구흡충류(Echinostoma sp.), 쥐요충류(Syphacia sp.), 분신충류(Strongyloides sp.) 등이었고 원충은 대장아메바(Entamoeba coli) 등이었다. 이상의 결과에서 인수공통 질환을 일으킬 수 있는 폐포자충, 쥐조충, 간흡충 등이 집쥐에 감염되어 있어 철저한 집쥐 관리가 요망된다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.83-84
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• 2016

A wideband stacked patch antenna with parasitic elements, rectangular and triangle shaped patches, is proposed. Two different shaped parasitic elements are placed in the above of main rectangular microstrip patch antenna in order to achieve wide bandwidth for 860 MHz band. Coupling between the main patch and parasitic patches is realized by thick air gap. The gap and locations of parasitic patches are found to be the main factor of the wideband impedance matching. The proposed antenna is designed on a ground plane with small size of $119mm{\times}109mm$ for application of compact transceivers. And the impedance bandwidth of the antenna should satisfied CDMA band to the 780MHz~890MHz.

• Korean journal of applied entomology
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• v.30 no.4
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• pp.233-240
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• 1991

A female Brachymeria lasus (Walker) was exposed to one or four pupae of host Hyphantria cunea Drury for 20 minutes within a petri dish $(1.5\times9cm)$ to learn factors influencing the host discrimination by the parasitoid. It rejected the parasitized host with its rejection ratio 73.3% for the one pupal exposure vs 100% for the four pupal exposure scheme. The parasitoid could discriminate the parasitized host by its antennal drumming and ovipositor probing due to a pheromone-like external marking which is effective only for a certain peiod of time, and a host quality associated with the parasitoid development, respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.7B
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• pp.875-879
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• 2001

마이크로스트립 패치안테나의 대역을 증가시키는 방법이 꾸준히 연구되고 있다. 본 연구에서는 구형 패치 구조에 기생 소자를 더한 형태로 구형 패치 외부에 바(bar)와 밴드(band) 모양의 기생소자를 설치하여 프린징 효과를 최소화 하고자 하였으며, 이로 인한 안테나 효율의 향상과 대역폭을 증가를 시키고자 하였으며, 또한 기생소자의 폭과 방사안테나의 간격을 조절하여 대역폭과 임피던스정합 특성의 변화를 해석하였다. 이를 이용하여 LMDS통신 주파수 대역인 24.6GHz∼28.5GHz에서 공진 대역을 갖도록 설계하였다. 정재파비 2.0 이하를 기준으로 기존의 패치안테나의 중심주파수에 대한 대역 이용율이 수 %인데 반하여, 본 연구에서 제시한 밴드를 설치한 구조의 경우 12.92%로 증가함을 알 수 있고, 또한 본 연구에서 제시한 외부 밴드를 갖는 구조가 급전선로와 패치 안테나와의 정합특성이 월등함을 확인하였다.

• Proceedings of the KIPE Conference
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• 2011.07a
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• pp.344-345
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• 2011

스마트 그리드 산업으로 인하여 신재생에너지의 활용이 중시되고 있는 시점에서 신재생에너지원을 더욱 효율적이고 안정적으로 사용하기 위해서는 에너지 저장장치의 필요성이 부각되고 있다. 신재생 에너지원을 사용하기 위한 부스트 컨버터와 충방전기를 설계시 일반적으로 시뮬레이션을 통해 설계를 하게 된다. 이때, 인덕터와 커패시터를 이상적인 소자라고 생각하고 시뮬레이션 하거나, 실제 하드웨어와 같이 인덕터와 커패시터에 기생하는 저항을 포함시켜 시뮬레이션을 하게 된다. 본 논문에서는 신재생 에너지원을 계통에 사용할 수 있도록 저전압 상태에서의 신재생 에너지원 출력전압을 승압시켜 인버터를 사용할 수 있도록 만들어 주는 부스트 컨버터의 인덕터를 이상적인 경우와 기생저항이 포함된 경우 각각의 조건하에서 충방전기와 연결하였을 경우 충방전기의 설계에 어떠한 영향을 주는지를 알기 위해 부스트 컨버터의 출력 임피던스 수식을 통해 분석한 MATLAB과 PSIM을 통해 시뮬레이션을 하여 증명하였다.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.99-105
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• 2002

A gregarious pupal endoparasitoid Tetrastichsus sp. (Hymenoptera: Eulophidae) was reared in vitro from oviposition to adult emergence on an artificial host. The host pupal case was made using 0.02 mm-thick polypropylene film, and was filled with a diet consisting of powders of Antheraea pernyi pupa, chicken yolk, infant formula, royal jelly, and Neisenheimer's salt solution. Female parasitoids reared in the artificial host produced smaller sized progeny than those reared in in vivo, but the adults reproduced fertile offsprings. Furthermore in vitro second-generation (G$_2$) females showed more improved biological characteristics, compared with their parents. The fecundity (mean no. adult progeny), oviposition period (days), and longevity (days) of G$_2$ female were evaluated as 45.7, 7.8, and 13.8, respectively Female biased sex ratio was obtained with 76.9% female progeny. The results demonstrated that Tetrastichus sp. is a promising parasitoid for in vitro mass production.

• Journal of IKEEE
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• v.22 no.1
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• pp.185-188
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• 2018

This paper describes the parasitic capacitance modeling according to the coil structure, section bobbin and winding method for hybrid choke coil with reduced parasitic capacitance capable of the EMI attenuation of broad bands from lower frequency to higher frequency applied in the EMI attenuation filter of LED-TV SMPS. Especially, the hybrid choke coil with reduced parasitic capacitance($C_p$) proposed in this paper can reduces the parasitic capacitance($C_p$) by adopting the winding methods of rectangular copper wire, compared to the conventional common mode choke coil with the winding method of automatic type. The first resonant frequency of the proposed hybrid choke coil has a tendency to increase as the parasitic capacitance is smaller and its impedance characteristics, especially in the high frequency bands, improves as the first resonant frequency increases. In the future, the proposed hybrid choke coil with reduced parasitic capacitance shows it can be actually utilized in not only LED-TV SMPS but also various applications such as LED Lighting, Note-PC Adapter, and so forth.