• Journal of fish pathology
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• v.24 no.3
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• pp.237-245
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• 2011

Disease survey was conducted to investigate the cause of high mortality in 23 farms of eel, Anguilla japonica, during the period from 2000 to 2010. Seven kinds of fish pathogens were confirmed in the tested fish, which included: Pseudodactylogyrus sp. (infection rate: 65.5%, 19/29 samples), aquabirnavirus (ABV, 62.5%, 15/24 samples), Edwardsiella sp. (44%, 11/25 samples), anguillid herpesvirus 1 (AngHV1, 16.7%, 2/12 samples), Heterosporis sp. (10.3%, 3/29 samples), Vibrio sp. (8%, 2/25 samples), Trichodina sp. (3.4%, 1/29 samples). The rate of single infection was 44.8% (13/29 samples), while 62.1% (18/29 samples) showed mixed type of infection with 2 to 5 different pathogens. The most predominant mixed infection were Pseudodactylogyrus sp.-Edwardsiella sp. (10.3%, 3/29 samples), Pseudodactylogyrus sp.-ABV (10.3%, 3/29 samples), Edwardsiella sp.-ABV (6.9%, 2/29 samples). Infection by the above infectious parasites, bacteria and virus was confirmed in tested eels of juvenile to adult sizes that were cultured at $25{\sim}30^{\circ}C$ in almost the examined farms.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.299-303
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• 2019

This study was conducted to investigate the species of native parasitoids attacking Phyllocnistis citrella and their parasitism in citrus orchards in Jeju, Korea. During the survey period from 2013 to 2014, seven parasitoids belonging to Chalcidoidea were found: majority of the parasitoids were Sympiesis striatipes with 73% and Quadrastichus sp. with 22% in Eulophidae. The others were Neochrysocharis sp., Pnigalio sp., Holcopelte sp., Ageniaspis sp. (Encyrtidae) and Trichomalopsis sp. (Pteromalidae). Average parasitism rate reached 10.7% in orchards with spraying insecticide, and 32.2% in environmental-friendly managed orchards.

• Geophysics and Geophysical Exploration
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• v.7 no.3
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• pp.164-173
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• 2004

To delineate geothermal water movement at the Pohang geothermal development site, Self-Potential (SP) survey and monitoring were carried out during pumping tests. Before drilling, background SP data have been gathered to figure out overall potential distribution of the site. The pumping test was performed in two separate periods: 24 hours in December 2003 and 72 hours in March 2004. SP monitoring started several days before the pumping tests with a 128-channel automatic recording system. The background SP survey showed a clear positive anomaly at the northern part of the boreholes, which may be interpreted as an up-flow Bone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. The first and second SP monitoring during the pumping tests performed to figure out the fluid flow in the geothermal reservoir but it was not easy to see clear variations of SP due to pumping and pumping stop. Since the area is covered by some 360 m-thick tertiary sediments with very low electrical resistivity (less than 10 ohm-m), the electrokinetic potential due to deep groundwater flow resulted in being seriously attenuated on the surface. However, when we compared the variation of SP with that of groundwater level and temperature of pumping water, we could identify some areas responsible to the pumping. Dominant SP changes are observed in the south-west part of the boreholes during both the preliminary and long-term pumping periods, where 3-D magnetotelluric survey showed low-resistivity anomaly at the depth of $600m\~1,000m$. Overall analysis suggests that there exist hydraulic connection through the southwestern part to the pumping well.

• Journal of Korea Port Economic Association
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• v.20 no.2
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• pp.151-167
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• 2004

Traditional traffic forecast has employed regression analysis or time-series analysis based on past trends of explanatory variables. However, not existing but planned port facilities do not have historical data for traffic estimation. Consequently, arbitrary traffic allocation has been subject to researcher's intuition. In this paper, container throughput at New Incheon Outer-South Port will be estimated using stated preference(SP) and sample enumeration methodology on the basis of survey data about the choice behaviors of port users in a theoretical situation. In the SP survey, shippers, freight forwarders and carriers were required to answer a choice between two alternative ports: Busan and Incheon. Although total 27 scenarios of questionnaires were constructed with 3 levels of 3 explanatory variables, each interviewee was asked to answer for just 9 scenarios chosen at random. A binary choice logit model was applied to the survey data. The elasticity of travel time is estimated to be very high, implying that building New Incheon Outer-South Port could be effective in relieving the congestion of the Kyungin corridor. The analysis result shows that increasing service level at Incheon Port would bring in the substantial diversion of container cargo in the Capital region to Incheon Port from Busan Port.

• Korean Journal of Veterinary Service
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• v.23 no.4
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• pp.341-348
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• 2000

Nowadays we continue to face challenges to the safety of our foods. It seems clear that contaminated meats provide the major route of listeria monocytogenes transmission from the environment to humans. L monocytogenes is the most important species associated with disease in humans among the listeria sp. The current incidence of symptomatic listeriosis caused by L monocytogenes is uncertain. Although the number of reports in the literature on listeriosis are increasing, it is likely that they are actually unrecognized or underreported because of a lack of awareness on the part of some laboratory workers who fail to isolate or identify these organisms. To get the information of sanitary development, we survey various meats (beef, pork, etc) in Kyongbuk area. Samples were collected from local meat shop at Kyongbuk area. Total sixty six case were isolated and identified from one hundreds and seven samples. L innocua was the most abundant in listeria sp. Among U isolates, the number of isolated L innocua was 43 (65.2%). The numbers of isolated L murrayi, L welshimeri, L monocytogenes and L seeligeri were 12(18.2%), 7(10.6%), 3(4.5%) and 1(1.5%), respectively, but L grayi, L iuanouii were not Isolated.

• Korean Journal of Veterinary Service
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• v.38 no.1
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• pp.13-17
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• 2015

Three serotypes (O, A and Asia1) of the foot-and-mouth disease (FMD) vaccine were injected into domestic cloven-hoofed animals in korea after the nationwide spread at the end of 2010. The purpose of this study was survey of FMD virus stuructural protein (SP) antibody titer in Yeongcheon by enzyme-linked immunosorbent assay (ELISA). Total 1,324 samples collected from 89 farms were tested. The overall seroprevalence of FMD virus SP antibodies was 58.8% (778/1,324) The seroprevalence of FMD virus SP antibody varied with species. Results in cattle (over 12 month old) and pig (90 to 130 day old) were 58.8% and 44.9% respectively.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.1-8
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• 1997

The aquatic animals of Tan stream were composed of 46 species, 28 families, 11 orders, 6 classes in 4 phyla during the survey period of April, 1996 to December, 1996. They were composed of 31 species in aquatic insecta, 6 species in annelida, 3 species in mollusca, 1 species in crustacea, and 5 species in fishes, respectively. Major dominant species in Tan stream were Chironomidae sp.1, Chironomidae sp.2, Chironomidae sp.3, Tubufucidae sp.1, Physa acuta and hirudo niponica. Dominance indices of benthic macroinvertebrates ranged highly from 95.74 to 100.00% at lower stream(site 4), but ranged 50.00 to 95.85% at site 1 through site 3. The aquatic animals ranged from 25 to 32 species at site 1 through site 3, but they were only 3 species at site 4 for survey period. Tan stream in the light of urban stream ecosystem has a little less riffle areas and hydrophyte areas by cementation of riparian area and channel type of water course. Therefore, the species of aquatic animals in Tan stream decreased because of deterioration of water quality according to reduction of self-purifcation ability and loss of microhabitat according to reduction of hydrophyte areas and riparian areas. The tendency of decreasing species of aquatic animals appeared seriously at lower stream From drive licence test authority at Kangnam-ku, Seoul to conjunction point of the Han river.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.570-607
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• 2023

The subgenus Tricoma Cobb, 1894 comprises free-living marine nematodes encompassing a total of 83 validated taxa. Within this diversity, twenty-one taxa thrive in the deep sea, while twenty-three are found in coral reefs, flat areas, or green algae. Additionally, eleven taxa inhabit the sublittoral zone at depths exceeding 10 meters, and the remaining taxa are situated on beaches, coasts, or in habitats lacking detailed information. In the course of a survey focused on the East Sea free-living marine nematodes, we identified four new and two previously unrecorded species belonging to the subgenus Tricoma. Specifically, two new species, Tricoma (Tricoma) breviseta sp. nov. and T. (T.) donghaensis sp. nov., were discovered in mud-sandy sediment in deepsea environments below 2000 meters within the Ulleung Basin and Hupo Bank. Two previously unrecorded species [T. (T.) paralucida Decraemer, 1987 and T. (T.) similis Cobb, 1912] and the two newly found species [T. (T.) longicauda sp. nov. and T. (T.) ulleungensis sp. nov.] were obtained from subtidal coarse sand at a depth of 20 meters during a survey of the waters surrounding Ulleungdo Island. The distribution and information on validated taxa within the subgenus Tricoma were systematically collected, reviewed, and cataloged. Detailed morphological features and illustrations of Tricoma species from Korea were provided through the use of differential interference contrast microscopy.

• Geophysics and Geophysical Exploration
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• v.5 no.4
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• pp.257-261
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• 2002

We have carried out integrated research including field survey and numerical modeling to appraise the applicability of SP method to the leakage problems of irrigation facilities. The leakage pattern of the dike studied here can be classified into the three categories: leakage through the abutment, leakage by piping through dike, and leakage due to the composite effects of landslide and distortion of the dike structure. for the numerical modeling to interpret quantitatively SP survey results acquired at dike, we have modified the computer code proposed by Sill (1983) to apply to the leakage problems. The numerical studies match the characteristic patterns of SP anomalies according to the leakage types and appear to be very useful to interpret the leakage zone and path. The SP monitoring results were also well coincided with tidal variations observed at every embankment so we found the SP method is quite effective not only to detect the leakage zone but also to determine the leakage trend. The numerical modeling results also reproduced the SP anomalies due to seawater leakage in the embankment.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.369-375
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• 2016

This survey was conducted during March to April 2014 in the main stream and tributaries of Xe Pian and Xe Namnoy in order to investigate fish fauna in the Bolaven Plateau. Fish belonging to twenty eight species and eight families were collected from the main stream and tributaries of Xe Namnoy and Xe Pian during the survey period. Among them, Devario salmonatus, Poropuntius bolovenensis, Annamia sp., Sewellia elongata, Schistura bolavenensis, Schistura sp.1, Schistura sp.2, Schistura sp.3, Schistura sp.4, and Macronathus sp. were endemic species in the Bolaven Plateau, indicating a high prevalence rate of endemic species (35.7%) in the area. Meanwhile, Kottelat (2000, 2013) has been reported that four species of Poropuntius inhabit the Bolaven Plateau. However, the major morphic characteristics of Poropuntius species found in the Bolaven Plateau were mostly overlapped, except for the shape of their mouth. The young fish of Poropuntius (> 70 mm SL) have only generalized mouth while the of adult fish the shape of their mouth have two phenotype (narrow and broad). Therefore, it is assumed that Poropuntius species in the Bolaven Plateau has trophic polymorphism as the same species exhibits two different mouth shapes.