• Korean Journal of Fisheries and Aquatic Sciences
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• v.6 no.3_4
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• pp.112-122
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• 1973

Philometroides carassii (ISHII, 1931) is a parasitic nematode of Carassius auratus and gold fish. Recently a large number of parasitized fishes by this nematode have been reported by fish farmers in Korea. The present investigation was aimed to find out the life cycles of the parasites and effects of chemotherapeutic medicines on the emerged larvae from the adult parasites. Results of the study are summarized as follows : 1. Intermediate host of p. cararsii is a freshwater copepod, Cyclops sp. and the invaded lavae in the body cavity of copepod are capable for parasitizing the fish host after 3 hours of invasion. 2. The lavae eaten directly by the fish host are digested or excreted. 3. The larvae invaded in the fish intestine through the intermediate host pass into the body cavity in 1 to 10 days, and become subadult stage. After 18 to 20 months the subadults parasitic in the body cavity of the Carassius auratus, penetrate through muscle fissile into tile caudal fin where they become adults. Whereas those parasitic in the body cavity of the gold fish, 7 to 8 months the sutadults penetrate through muscle tissue into the caudal fin where they become adults. 1. Male subadults found in the body cavity of the Carassius auratus and gold fish, were larger than females, This is the first record of male subadults occurring in the fish host. 5. Among four different :drugs tested, most of all larvae died in 4 ppm of dipterex in 5 days. But no adults were harmed even in 6 ppm dipterex in 11 days.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.27-34
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• 1996

The geographical distribution and population density of rodents and chigger mites at six localities of Chollanam-do were investigated from October to December in 1993. Among total 142 field rodents collected by the modified Chemin wooden traps, 131 rodents were Aponemw usrari,us (92.3%) and 11 were Crocidurc losiurc (7.7%). Out of 142 field rodents, 92 were parasitized by chiggers, showing 69.0% of the infestation rate and 74.2 of the chiggor index. Infestation rate and chigger index of A. omfernrius and C. lusiurc were 73.3%, 80.4 and 18.2%, 0.5, respectively. From the trapped field rodents, 10,532 chiggers were collected and identified with 11 species of 4 genera. Leptotrombidium pcLLinun. the vector 3pecies of tsutsugamushi disease, was the dominant species, showing 8,038 chi99ers (76.31%). L. scutellnre was the second dominant species showing 1,359 chiggers (12.9%). The distribution of chigger mites was clearly localized by the species, showing the different dominant species according to localities. The predominant species was 1. scutellare (100%) in Changhung-gun, 1. scutellcre (41.5%) in Posong-gun, 1. pnllidum (88.8%) in Hwasun- gun, 1. pnLlidunl (59.2%) in Koksong-gun, 1. zetum (77.3%) in Hampyong-gun, and 1. pclpcle (63.4%) in Tamyang-gun. Regarding to the geographical distribution of chigger population density, the infestation rate and chigger index was most high in Hwasun-gun as 62.4% and 216.2 respectively, and next high in Koksong-gun as 22.4% and 77.7%, respectively.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.393-400
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• 2010

The parasitism, development time, hatchability, and progeny production of Trichogramma chilonis(TC) females developed in eggs of Helicoverpa assulta (HAs), Cadra cautella (CC), and Helicoverpa armigera (HAr), respectively, were compared with those developed in reciprocal eggs at constant temperatures of $25{\pm}2^{\circ}C$ and relative humidity of 50~70% under 16L-8D. Developmental performances of TC reared in each of the three hosts on the following hosts(host tested) appeared differently, and were affected most by the size of the proceeding hosts and test host. Among the parameters parasitism and progeny production were affected more than others. Parasitism was significantly different between the treatments, lowest in CC-HAr($10.1{\pm}2.05%$) and highest in HAr-HAs($47.0{\pm}2.09%$), and the hatchability showed similar pattern. Development time as well was shortest in the CC-HAr where previous host is smallest and test host is biggest. The highest number of progeny production of TC was observed in HAr-HAs($93.9{\pm}6.87$ wasps), and the lowest was CC-HAs($18.4{\pm}6.36$ wasps).

• Korean Journal of Plant Resources
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• v.22 no.2
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• pp.136-144
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• 2009

Germination tests on 3 species that have potential for use as sprout vegetables, such as Coreopsis tinctoria, Saussurea pulchella, and Matricaria recutica, were conducted for 20 days under different temperatures of $15{\sim}30^{\circ}C$, and conditions of light and dark. C. tinctoria showed germination of 83% under $15^{\circ}C$ and dark condition after 4 days, S. pulchella 51.7% under $25^{\circ}C$ and light condition after 20 days, and M. recutica 90.3% under $25^{\circ}C$ and dark condition after 4 days. To investigate optimum plantlet size before greening treatment, seeds germinated were allowed to grow under darkness. The optimum growth of C. tinctoria was obtained under $30^{\circ}C$ after 5 days, S. pulchella under $25^{\circ}C$ after 6 days, and M. recutica under $20^{\circ}C$ after 6 days. Greening treatment resulted in diminished longitudinal growth, but C. tinctoria and S. pulchella showed more vigorous latitudinal growth. Days required before marketing as sprout vegetables were different according to species - Three days of greening was good for C. tinctoria, 2 for S. pulchella, no greening for M. recutica. Generally, tightly sealed containers for minimum water loss were recommended for storage of sprout vegetables after harvest. However, storage methods for each species were different depending on various factors like temperature of storage, presence of ventilation holes of storage packages and forms of marketing. More detailed research for above 3 species is proposed.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.123-158
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• 2009

An attempt was made to stimulate future research by providing exemplary information, which would integrate published knowledge to solve specific pest problem caused by resistance. This review was directed to find a way for delaying resistance development with consideration of chemical(s) nature, of mixture, rotation, or mosaics, and of insecticide(s) compatible with the biological agents in integrated pest management (IPM). The application frequency, related to the resistance development, was influenced by insecticide activity from potentiation, residual period, and the vulnerability to resistance development of chemical, with secondary pest. Chemical affected feeding, locomotion, flight, mating, and predator avoidance. Insecticides with negative cross-resistance by the difference of target sites and mode of action would be adapted to mixture, rotation and mosaic. Mixtures for delaying resistance depend on each component killing very high percentage of the insects, considering allele dominance, cross-resistance, and immigration and fitness disadvantage. Potential disadvantages associated with mixtures include disruption of biological control, resistance in secondary pests, selecting very resistant population, and extending cross-resistance range. The rotation would use insecticides in high and low doses, or with different metabolic mechanisms. Mosaic apply insecticides to the different sectors of a grid for highly mobile insects, spray unrelated insecticides to sedentary aphids in different areas, or mix plots of insecticide-treated and untreated rows. On the evolution of pest resistance, selectivity and resistance of parasitoids and predator decreased the number of generations in which pesticide treatment is required and they could be complementary to refuges from pesticides To enhance the viability of parasitoids, the terms on the insecticides selectivity and factors affecting to the selectivity in field were examined. For establishment of resistant parasitoid, migration, survivorship, refuge, alternative pesticides were considered. To use parasitoids under the pressure of pesticides, resistant or tolerant parasitoids were tested, collected, and/or selected. A parasitoid parasitized more successfully in the susceptible host than the resistant. Factors affecting to selective toxicity of predator are mixing mineral oil, application method, insecticide contaminated prey, trait of individual insecticide, sub-lethal doses, and the developmental stage of predators. To improve the predator/prey ratio in field, application time, method, and formulation of pesticide, reducing dose rate, using mulches and weeds, multicropping and managing of surroundings are suggested. Plant resistance, predator activity, selective insect growth regulator, and alternative prey positively contributed to the increase of the ratio. Using selective insecticides or insecticide resistant predator controlled its phytophagous prey mites, kept them below an economic level, increased yield, and reduced the spray number and fruits damaged.

• The Journal of the Korea Contents Association
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• v.20 no.6
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• pp.51-63
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• 2020

This study analyzed newspaper reports in the United States and South Korea that focused on Parasite's unprecedented performance at the 2020 Academy Awards. The research focused on the power relationship between 'the established and the outsiders (Elias & Scotson, 1994)' as represented by the Academy Awards and Parasite, respectively. Qualitative content analysis and text analysis were conducted to examine the reporting of American and South Korean newspapers and illuminate three aspects of the power relations between the Academy Awards and Parasite. Three major findings were derived. First, the Academy traditionally has a reputation for marginalizing films with a non-English or Asian background, but recognition of Parasite at the 92nd ceremony changed the Academy's established position of power. Second, historically, the Academy Awards had been characterized by a group charisma that exerts stigmatization (through an English-oriented policy and language stigmatization) and accords North American films priority over non-English movies. Lastly, the reports of newspapers in the two countries are generally similar, but the Korean articles internalized the individual, society, and the state.

• Parasites, Hosts and Diseases
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• v.30 no.4
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• pp.349-354
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• 1992

A mass treatment of head louse infestation with SumithrinB powder (0. 4% phenothrin) in primary school children was implemented during the period of September 1991-May 1992. The infestation rate of total 2,515 children was 38.6% in average (21.2 % in boys and 57.5% in girls) . The reduction rate of head louse infestation was 93.4% with a single treatment and 94.8% with double consecutive treatments with about 10 days interval, which indicated that a single treatment would be recommended for the mass treatment in the community. Long term follow-up after Sumithrin powder application for head louse control in a primary school showed that the infestation rate dropped from 33.1% before treatment to 5.4% by seven months after treatment, giving a 83.4% reduction rate. Key words: Mass treatment, Sumithrin powder, head louse, Korea.

• Journal of the korean veterinary medical association
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• v.46 no.1
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• pp.63-72
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• 2010

지구상에 서식하고 있는 포유강(Class: Mammalia), 박쥐목(Order: Chiroptera)에 속하는 박쥐류는 1,000여종에 이르는 것으로 알려졌으며, 포유류 중에서 1/4을 차지하고 있으며, 그 2/3는 곤충류를 포식하는 식충성을 지니고 있다. 우리나라에 서식하고 있는 박쥐류는 관박쥐과(Family:Rhinolophidae) 2종, 애기박쥐과(Family: Vespertilionidae) 28종, 큰귀박쥐과(Family: Molossidae) 1종으로서 총 31종이며, 모두 식충성 동물이다. 흡충류라고 하는 것은 편형동물문에 속하는 기생성 동물의 한 군으로서, 항온동물의 장이나 그 밖에 조직에 기생하는 것은 모두 하나 또는 두개 이상의 중간숙주를 필요로 하는 이생 흡충이다. 제1중간숙주는 고둥이지만 제2중간숙주는 여러 가지 변온동물로서 그 대부분은 생활사에 있어서 수서 생활을 하는 시기가 있는 것에 한정되지만 이는 제1중간숙주의 체내에서 형성된 꼬리유충이라고 하는 흡충류의 유생이 보통 물 속을 헤엄쳐 다니다가 제2중간숙주에 침입하게 된다. 박쥐류는 여러 가지 땅강아지나 개똥벌레를 포식하기 때문에 이들 유생이 물 속에서 흡충류의 피낭유충에 감염되었을 경우 박쥐류가 흡충류의 종숙주로서 적합하면 그 체내에서 피낭유충이 장에서 탈랑하여 드디어 성충으로 된다. 만일, 감염된 수서 곤충의 유생이 우화되면 그 유생 시대에 감염된 피낭유충이 그 숙주의 변태와는 상관없이 그 기생이 이어져 적당한 종숙주에게 섭취되기를 기다리게 된다. 우리나라에 있어서 박쥐류에 기생하는 흡충류에 관한 조사 연구는 일찌기 도쿄문리과 대학 동물학 연구실의 Ogata(1938)에 의하여 이루어진 이래 경성제국대학 의학부의 Park(1939a,b)과 후쿠오까대학 의학부의 Kifune et al.(1983, 1997)이 있을 뿐 우리나라 학자에 의한 연구 보고는 접할 수 없는 형편이다. 그럼으로, 우리나라 학자도 이에 관한 더욱 더 깊은 관심을 가져야할 것으로 생각하는 바 이에 지금까지 보고된 자료를 종합, 검토하여 기술하고자 한다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.12
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• pp.1-9
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• 2000

A new method, the external resistance method (ERM method), is proposed for accurate extraction of the gate bias-dependent effective channel carrier mobility (${\mu}_{eff}$) and separated parasitic source/drain resistances ($R_S$ and $R_D$) of n-channel MOSFET's. The proposed ERM method is applied to n-channel LDD MOSFETs with two different gate lengths ($W_m/L_m=30{\mu}m/0.6{\mu}m,\;30{\mu}m/1{\mu}m$) in the linear mode of current-voltage characteristics ($I_D-V_{GS},\;V_{DS}$). We also considered gate voltage dependence of separated $R_2$ and $R_D$ in the accurate modeling and extraction of effective channel carrier mobility. Good agreement of experimental data is observed in submicron n-channel LDD MOSFETs. Combining with capacitance-voltage characteristics, the ERM method is expected to be very useful for accurate and efficient extraction of ${\mu}_{eff},\;R_D,\;R_S$, and other characteristic parameters in both symmetric and asymmetric structure MOSFET's in which parasitic resistances are critical to the improvement of high speed performance and reliability.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.11 s.114
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• pp.1082-1088
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• 2006

A turnstile antenna using the parasitic monopole has been developed for STSAT-2 TT&C application. The antenna consists of two radiating elements; a bow-tie dipole and a parasitic monopole. The bow-tie dipole is main radiating element, used a bow-tie structure for bandwidth improvement and size reduction. The parasitic monopole improved beamwidth and axial ratio. The input impedance of the antenna is about 50 ohm without a matching circuit. The proposed antenna has beamwidth of $>140^{\circ}$, axial ratio of < 3 dB and VSWR of < 1.5 in the band of $2.075{\sim}2.282GHz$.