• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.34 no.4
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• pp.386-392
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• 1998

• Tribology and Lubricants
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• v.22 no.5
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• pp.282-289
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• 2006

This paper is to investigate the wear behaviors of two type ceramics, $Al_{2}O_{3}\;and\;TiO_{2}$, by coated plasma thermal spray method under the lubricative environment. The lubricative environments are grease fluids, a general hydraulic fluids, and bearing fluids. The wear testing machine used a pin on disk type. Wear characteristics, which were friction force, friction coefficient and the specific wear rate, according to the lubricative environments were obtained at the four kinds of load and sliding velocity is 0.2 m/sec. After the wear experiments, the wear surfaces of the each test specimen were observed by a scanning electronic microscope.

• Journal of the korean veterinary medical association
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• v.23 no.5
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• pp.289-301
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• 1987

Outbreaks of foulbrood in honey bees rearing on Cheju Island(an apiary with 172 colonies) and in Pusan City(an apiary with 100 colonies) were reported in April, 1987. The disease striked on Cheju Island was identified as American foulbrood caused by Bacil

• The Korean Journal of Soil Zoology
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• v.2 no.2
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• pp.76-82
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• 1997

Mortality of some agro-forest insect pests, Agrotis segetum, Blitopertha orientalis, Agerastica coerulea, Glyphodes perspectalis and Acantholyda parki caused by entomopathogenic nematodes was investigated in laboratory and in pot. Steinernema carpocapsae All and Pocheon strain were effective against 2nd of 3rd instar larvae of A. segetum showing 100% mortalities at the concentration of 10Ijs/larva but not effective against 4th inster larvae. Mortality of B. orientalis was 100% after 26 days in H. bacteriopora NC 1, H. bacteriophora Hamyang and S. glageri NC strain treatment. S. monticulum also showed 100% mortalities against A. coerulea andd G. perspectalis at the concentration of 80 and 40 Ijs/larva. However, H. bacteriophora Cheju and S. glaseri Cheju strain were not effective against A. parki, i.e., showing 23.3 and 20.0% mortalities, respectively at the concentration of 160Ijs/larva. S. glaseri Hanrim strain was more effective than H. bacteriophora Cheju strain against Pryeria sinica.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.845-851
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• 1998

In order to manage the water quality from the flowing streams in Cheju Island, the characteristics of water quality was investigated from August, 1996 to May, 1997 and the pollutant loadings for future were estimated from the watershed at each stream. Comparing the mean concentrations of each water quality with the criterion of water quality in river, it was under I class except for Changgo Stream, for DO, under I class at the whole station for SS and under II class for BOD. As the pollutant loadings at each stream in 2020 is compared with those in 1996, the estimated results are as follows : 1) for BOD, 59% at Donghong Stream, 24% at Yeonoe Stream, 44% at Ohngpo Stream and 57% at Changgo Stream. 2) for T-N, 91% at Donghong Stream, 76% at Yeonoe Stream, 63% at Ohngpo Stream and 89% at Changgo Stream. 3) for T-P, 69% at Donghong Stream, 42% at Yeonoe Stream, 45% at Ohngpo Stream and 73% at Changgo Stream. The point source loadings discharged through combined sewer could be treated at sewage treatment plant. However, the expected slow decreasing rate of BOD, T-N, and T-P loadings is due to the part of untreated nonpoint source loadings. Nonpoint source loading overflow typically occurs when the flow of stormwater combined with sewage exceeds the capacity of the interceptor sewers. Since most of the sewers used in Cheju Island are the combined sewers, the combined overflow sewage is bypassed into the receiving water area after a rainstorm. Therefore, a means to control nonpoint source loadings should be considered for the river and marine water quality management.

• Korean Journal of Animal Reproduction
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• v.10 no.1
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• pp.58-65
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• 1986

The results from a survery on the reproduction of a, pp.oximately 500 dairy cows raised in four different farming areas including Cheju city, Jochun, Hallim and Sung-up are summarized as follows; 1. At the occurrence of first estrus, the average age of the heifers was 15.1 months (330 Kg/B.W.), and at first conception 18.0 months (354Kg/B.W.). There was no regional differences. 2. The average interval of the estrous cycle was 20.4 days. And the repetition of esturs after unsuccessful insemination occurred on an average of 1.6 times, especially 2.0 times in the herds of the Jochun district. 3. The ages at the first calving were similar to the data recorded for the domestic mainland's herds at 27.1 months. But some regional differences were recognized within the four districts: i.e. 28.6 (Cheju city), 27.4(Jochun), 27.1(Hallim) and 25.3 months (Sung-up). There was no significant differences in sex ratio of newborns at 50.4%(♂) and 49.6%(♀). 4. The intervals of esturs recurrence and the following conception after calving were 80.0 and 95.8 days respectively. In the followsing conception intervals after cavling, 90.6-97.4 days were average for the herds of Cheju city and Jochun districts, 62.4-69.7 days for those of Hallim and Sung-up districts. 5. The average gestation period was 279.8 days, and was almost identical in the four districts. 6. The calving intervals was 377.7 days in average, and it was shorter than the data recorded for the domestic mainland's herds. Also it was reduce gradually according to the calving frequency.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.229-233
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• 1974

The author studied On the inorganic substances in the muscles of Branchiostegus joponicus japonicus, Chromis notatus, Haliotis gigantea mataka, obtaining the following results ; 1) The results of quantitative analysis are shown in Table 3. 2) It is noticeable that the concentration of Cu, P, Fe, Ca, and Na in the muscles of Branchiostegus joponicus japonicus (demersal fish), Chromis notatus (pelagic fish) and Haliotis gigantea mataka (shell fish) are quite different in the three species.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2005.11a
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• pp.147-150
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• 2005

Fixed lighting of public ways for both vehicles and pedestrians can create a nighttime environment in which people see comfortably and can quickly and accurately identify objects on the roadway being travelled roadway lighting can improve traffic safety, achieve efficient traffic movement and promote the general use of the facility during darkness. The design of a roadway lighting system involves consideration of visibility, economics, esthetics, safety and environmental conditions. This paper describe estimation of horizontal illuminance by actual measurement at main streets in Jejusi. We try to evaluate Jejusi Roadway Lighting Conditions for modeling by computer simulation.

• Korean Journal of Environmental Biology
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• v.23 no.2 s.58
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• pp.206-213
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• 2005

The diurnal and seasonal variations of antioxidative enzyme activity and the O-J-I-P transients were investigated from the leaves of Crinum asiaticum var. japonicum under winter stress in natural habitat, in order to diagnose quantitatively physiological states of plants under stresses. The activities of superoxide dismutase and peroxidase increased slightly in winter. Especially, peroxidase acitivity was higher at dawn and night in winter and some isoforms were detected only in early winter. In the O-J-I-P transients, the fluorescence intensity of J, I, P steps decreased significantly in winter season, contrary to its high value in summer season. Of the chlorophyll fluorescence parameters derived from the O-J-I-P transients, Fm and $\Phi_{po}$ decreased with the increase of ABS/RC depending on temperature drop in winter.

• Korean Journal of Veterinary Research
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• v.48 no.3
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• pp.323-326
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• 2008

A two-year-old mixed breed sow was requested to the Veterinary Pathology Laboratory of Cheju National University with a clinical signs of severe abdominal pain and sudden death. Grossly, there was severe hemorrhage in abdominal cavity. Most of internal parenchymas and subcutaneous muscle showed severe pale discoloration. Both ovaries were enlarged with oval to round protruding multilobular masses and dark red in color. And they were firm and contained multiple small cysts in their cut surface. Histopathologically, numerous neoplastic granulosa cells had spherical-to-oval, hyperchromatic nuclei and scant eosinophilic cytoplasms were distributed with follicular pattern in ovarian masses. And the typical Call-Exner bodies, distinctive microcavityies, were observed in the center of small neoplastic follicles. Based on the gross and histopathologic findings, this case was diagnosed as granulosa cell tumor. In our best knowledge, this is believed to be the first report of granulosa cell tumor in a sow in Korea.