• Journal of Animal Environmental Science
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• v.14 no.2
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• pp.105-112
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• 2008

This study was carried out to investigate evaporation rate of moisture per surface area and degradation rate of organic matter in full scale escalator reversing composting facility were analyzed to develope a computer program for the computation of an optimum volume of composting facility according to handling methods of swine farm, moisture levels of manure, degradation rate of organics and evaporation rate of moisture during composting. The obtained results can be followed as bellow; The temperature in full scale escalator reversing composting facility during composting reached $70^{\circ}C$ in 4 days and maintained until 11 days. Reduction rate of moisture and density was average 1.20% and 29.7%, respectively. Annual degradation rate of organic matter was 3.53%, showing lowest rate in winter as 3.23%. These seasonal degradation rate could be a factor to be considered for proper management and installation of composting facility. When computed with the amount of feces, urine, slurry and manure plus wastewater produced, the optimum volumes of composting facility for slurry and manure plus wastewater including each 95% moisture was $229m^3$ and $277m^3$, respectively, showing 21% ($48m^3$) difference.

• Korean Journal of Remote Sensing
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• v.33 no.6_1
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• pp.917-930
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• 2017

To understand the temporal and spatial variations of surface chlorophyll-a concentration (Chl-a) distribution in the Indian Ocean ($30^{\circ}E{\sim}120^{\circ}E$, $30^{\circ}S{\sim}30^{\circ}N$) by the Indian Ocean Dipole (IOD), we conducted EOF and K means analyses of monthly satellite-derived Chl-a data in the region during 1998~2016 periods. Chl-a showed low values in the central region of the Indian Ocean and relatively high values in the upwelling region and around the marginal regions of the Indian Ocean. It also had a strong seasonal variation of Chl-a, showing the lowest value in the spring and the highest value in summer due to the change of the monsoon and current system. The EOF analysis showed that Chl-a variation in EOF mode 1 is related to ENSO (El $Ni{\tilde{n}}o$/Southern Oscillation) and that of mode 2 is linked to IOD. Both modes explained spatially opposite trends of Chl-a in the east and west Indian Ocean. From K means analysis, the Chl-a variation in the east and west Indian Ocean, and around India have relatively good relationship with IOD while that in the tropical and middle Indian Ocean closely associated with ENSO. The spatial and temporal distribution of Chl-a also showed distinct spatial and temporal variations depend on the different types of IOD events. IOD classifies two patterns, which occurred during the developing ENSO (First Type IOD) and the year following ENSO event (Second Type IOD). Chl-a variation in the First Type IOD started in summer and peaked in fall around the east and west Indian Ocean. Chl-a variation in the Second Type IOD occurred started in spring, peaked in summer and fall, and disappeared in winter. In the Chl-a variation related to IOD, developing process appearing in the Chl-a difference between the east and west Indian ocean was similar. Chl-a variation in the northern Indian Ocean were opposite trend with changing developing phase of IOD.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6958-6965
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• 2014

This study examined the occurring pattern of potential risky species and the related abiotic factors for port-specific environmental management considering the control of ballast water-induced foreign species at Incheon seaport. From a total of 62 species observed during the study, 13 red-tide and 7 toxic phytoplankton, normally occurring species in Korean waters, occurred from the seasonal investigation at the inner and outer sites of the Incheon seaport from 2007 to 2009. The number of potential risky phytoplankton was relatively high at the outer site of the port during summer and winter. Red-tide species, such as Skeletonema spp., Thalassiosira nordenskioldii, and Paralia sulcata, dominated the total standing crops at the inner site (avg. 72.4%) and outer site (avg. 77.6%) in spring and summer, being positively correlated with the concentrations of total suspended solids (TSS) and pH (p<0.05). In summer, the red-tide species (Skeletonema spp.) and toxic species (Alexandrium catenella, A. tamarense, Dinophysis acuminata and Pseudo-nitzschia spp.) co-dominated (avg. 74.2%) at the inner site, while Skeletonema spp. and P. sulcata predominated (avg. 67.2%) at the outer site. During the study periods, the toxic species were significantly and positively correlated with the chemical oxygen demand (COD), dissolved inorganic nitrogen, silicate and phosphate (p < 0.05). The chlorophyll-a (chl-a) concentration of phytoplankton at the outer site ranged from 1.49 to $5.46{\mu}g/L$ on average, which was 3-5 times higher than that at the inner site in spring, summer and autumn, whereas there was no difference in the concentration between inner (avg. $0.94{\mu}g/L$) and outer (avg. $0.95{\mu}g/L$) sites in winter. In summary, diverse red-tide species dominated and a relatively high chl-a concentration existed at the outer site, whereas a relatively high number of toxic species and low chl-a concentration was observed at the inner site in summer. The potential risky species can outbreak in association with the concentration of nutrients, COD and TSS, suggesting that distinctive management of potential risky species is needed considering the environmental characteristics of Incheon seaport.

• Korean Journal of Veterinary Service
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• v.24 no.3
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• pp.223-241
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• 2001

From September 1996 to September 1999, 419 Korean-native calves with diseases under 6-month old collected from Kyonggi, Chungcheong, Chonlla and Kyongsang were examined by clinical, microbiological, parasitic, hematologic and histopathological mean. Among them, 124 cases were tested about the neutralization antibodies against infectious bovine rhinotracheitis virus(IBRV), Parainfluenza-3 virus(PI-3V), bovine uiral diarrhea virus(BVDV), bovine ephemeral fever virus(BEFV). In calf diseases in the survey, enteric diseases(72.8%) were most frequently involved and the following orders were taken by respiratory(17.4%) and reproductive (5.0%) disorders. In the causative pathogens associated with calf diseases and motality, 48.4% was induced by bacteria origin and also 35.6% by viral agents. Calf mortality was up to 76.3% in the cae of bacterial diseases and 55.7% in viral diseases. In bacterial diseases, frequent disorders were composed of colibacillosis(52.7%), salmonellosis(13.8%), pasteurellosis(12.8%) and campylobacteriosis(3.9%) and their mortalities showed 73.8% in colibacillosis, 73.0% in pasteurellosis, 67.9% in salmonellosis and 50.0% in campylobacteriosis (50.0%). Among the outbreaks of viral diseases, there were BVD(22.8%), bovine rotavirus infection(20.8%), bovine coronavirus infection(16.8%), bovine respiratory syncytial virus infection(15.4%), IBR(15.4%). Akabane disease(4.7%) and Chuzan diseases(3.4%). Interesting results through this studies were obtained the first isolate to Chuzan virus and Ainovirus in Korea which could be promised the development for diagnostic method and vaccines soon. Calf mortality to Akabane and Chuzan diseases was 100%. Main parasitic diseases were occupied by coccidiosis and babesiosis and their mortality of babesiosis was 20.0%. Other diseases were abomasal impaction(6.7%) and toxicosis(4.5%). The mortality of abomasal impaction was 89.3%. In some causes with malformations(1.9%) were confirmed as anasarca, derodidymus, polymelia, humerus hypoplasia, and tracheal collapse. Calf diseases had mostly been occurred in one month old grout (52.5%) and its prevalence was 25.1% in two to three month old group and 22.4% in four to six month old group. In calf mortality by age, there were 37.9% in one month old group, 18.1% in two and three month old group, and 13.8% in four to six month old group, respectively. The older the age of calf, the less the prevalence of calf enteric diseases. Respiratory diseases in calves to be tested frequently occurred in one to two month old group (41.4%). In one month old calves, the prevalence of enteric disease was 80.0%(p<0.05) and that of reproductive and respiratory disease was 9.5% and 8.2%, respectively. In two month old and four to six month old, enteric disease was 65.7% and 63.8% and respiratory disease was 28.6% and 26.6%. Seasonal prevalence and mortality of Korean-native calf diseases were not a significant difference. Prevalence of calf diseases in summer(31.5%) frequently occurred to compare that in winter(20.3%). Abortion and malformation in calves frequently occurred in spring. Hematological values in 84 calves with clinical signs showed mild to marked leukocytosis. Also, there was slight increase in hematocrit, platelet, mean corpuscular volume and mean plasma volume, but all of those were included the higher level to normal ranges. Calves with respiratory signs showed slightly erythrocytosis. One hundred seventy three calves without clinical signs were not significant different to ill cases in hematological values, but number of platelets was in higher normal range. In 125 calves, 84.8% was taken the antibody to IBRV, but 72% with the antibody had recorded the titer level lower than log$_2$5. The neutralizing antibody levels of higher than $log_{2}5$ to PI-3V and BVD virus were 60.8% and 67.2% cases, respectively. There were the cases of 57.6% had the neutralizing antibody level lower than log$_2$5 to BEFV.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.3
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• pp.222-229
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• 2009

This study was performed to evaluate effect of different fertilization management practices on soil microbial activities and community structure using soil enzyme activities and PLFA contents in volcanic ash citrus orchard soil. Six experiment plots have differently managed based on the recommended application rate(NPK) of chemical fertilizer and compost for 13 years. Experiment plots were composed of no-fertilization(control), compost only, half amount of NPK with compost (1/2NPK+COM), NPK, NPK with compost(NPK+COM), and 3 times amount of NPK(3NPK). Soil samples collected in early March, May, July, and September 2007. Urease activity was high at NPK+COM in March, May, and September. It was higher in NPK+COM than in NPK. Urease activity decreased according to the order NPK>compost>control in March and May; compost>NPK>control in July and September. Dehydrogenase activity was significantly higher in 1/2NPK+COM($4.3ug\;TPF\;g^{-1}\;24h^{-1}$) than in control($2.4ug\;TPF\;g^{-1}\;24h^{-1}$), May. $\beta$-glucosidase activity was significantly higher in NPK and 1/2NPK+COM than in control, May. In March, Total PLFA contents were higher in NPK+COM($349.2n\;mol\;g^{-1}$) than in 3NPK($228.5n\;mol\;g^{-1}$). And that were higher in 1/2NPK+COM($237.8n\;mol\;g^{-1}$) than in 3NPK($133.1n\;mol\;g^{-1}$), May. Distribution ratio of soil microbial groups by PLFA biomaker were not significantly difference in between seasonal and treatments. Principal component analysis by PLFA profiles showed that microbial community in compost and 3NPK plot were different compared with other treatments in March. But Differences in compost and 3NPK plot were not found in May. Our result showed that the change of microbial community structure affected by fertilization effect and seasonable variation.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.230-240
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• 2008

The primary aim of this study is to estimate the home range of a pair of raccoon dogs(Nyctereutes procyonoides koreensis) and to compare with the previous study of raccoon dogs in a rural area of Gurye, the southern part of South Korea. Radiotracking was regularly carried out on 2 raccoon dogs for 2 days every 2 months(in June, August, October and December, 2006). During the 2 days, radiotracking was usually conducted every $1{\sim}3$ hours through day and night. The analysis of tracking data with a total of $46{\sim}64$ bearings showed that the total home range size of the pair was $0.41km^2$, and mean home range size was $0.32km^2$ by 95% minimum convex polygons(MCP) estimate. The home ranges of the male and female were largely overlapping(about $70{\sim}95%$), and the sizes were not very much different from each other. However, there was a big difference between day $(0.01km^2)$ and night-time $(0.35km^2)$ home ranges, and it was largest in summer$(0.56km^2)$ and smallest in winter $(<0.01km^2)$. In addition, the home range of the pair included 1 core area and 4 different feeding areas. In conclusion, our raccoon dog home range data using the same individuals but with more frequent bearings per day and more extended tracking intervals still showed very similar results to the previous study with less frequent bearings per day and more extensive tracking days.

• Korean journal of applied entomology
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• v.43 no.4 s.137
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• pp.281-289
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• 2004

The sex pheromone blend (28-12AC : E8-12AC : Z8-12OH = 95 : 5 : 1) of oriental fruit moth, Grapholita molesta (Busck), was evaluated with reference to its male attractivity at different dosage and lure longevity of 1.0 mg in a field condition. Also, degree-days (DD) were calculated up to major phenological events of G. molesta using seasonal adult flights monitored by pheromone traps and egg population densities in early season in Suwon peach orchards. In the range of 0.1-4.0 mg dosage examined, G. molesta males caught in pheromone trap decreased with increasing total pheromone doses. The highest number of G. molesta males were attracted in traps baited with 0.1 mg-lure, and there were no significantly differences among 0.5 to 4.0 mg-lure. In longevity test with a 1.0 mg-lure, there was no difference in mean numbers of G. molesta males caught between traps with fresh-baited lures every 20d and field-lasted lures up to ${\approx}50d$ after trap installation, but thereafter more G. molesta males were attracted in the field-lasted lures than in the fresh-baited lures. Accumulated degree-days (DD) from January 1 to the first adult emergence (biofix) were 39DD at a lower threshold temperature $8.1^{\circ}C$. Degree-days from the biofix up to the 1st adult peak through 4th peak were 98DD, 620DD, 1233DD, and 1916DD, respectively. Required degree-days from the 1st adult peak to the 1st egg peak were 130DD, while the 2nd egg peak timing was simultaneous with the 2nd adult peak. Further, management strategies of G. molesta were discussed in peach orchards.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.3
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• pp.141-150
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• 2015

Dinoflagellates are ubiquitous and important primary producers in the oceans. They have diverse trophic modes, i.e., phototrophic, heterotrophic, and mixotrophic modes and thereby, play important ecological role in marine microbial food-web. While many studies have been focused on planktonic dinoflagellates in pelagic ecosystems, benthic, sand-dwelling dinoflagellates that inhabit in intertidal zone have been very poorly documented worldwide. We investigated biodiversity, occurrence, and molecular phylogeny of benthic, sand-dwelling dinoflagellates from the intertidal flat of Dongho, west coast of Korea during low-tide, monthly from November 2012 to February 2014. About 27 species of 13 genera in orders Gonyaulacales, Gymnodiniales, Peridiniales, Prorocentrales have been identified, of which members in the genus Amphidinium constituted a major part of the sand-dwelling dinoflagellates in this area. A total of 34 isolates from 16 species of the sand-dwelling dinoflagellates were isolated from Dongho, Mohang, Gamami, and Songho in the west coast and Hyupjae in Jeju of Korea, their 28S rDNA sequences were successfully amplified, and applied for molecular phylogenetic analyses. In the 28S rDNA phylogeny, Amphidinium species diverged across three major clusters within the order Gymnodiniales and formed polyphyletic group. Based on the unambiguously aligned partial 28S rDNA sequences including variable D2 region, the genotypes of Amphidinium mootonorum Korean strains greatly differed from that of Canadian strain with 19.2% of pairwise nucleotide difference, suggesting that further ultrastructural studies may provide additional characters to clearly separate these genotypes. Two potential toxic species, Amphidinium carterae and A. operculatum appeared occasionally during this study. Quantitative assessment and toxicity of those species should be addressed in the future.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.407-414
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• 2013

This study was carried out to understand the physiological characteristics of 'Manpungbae' (Pyrus pyrifolia Nakai) pears through the seasonal changes of pericarp structure and anatomical differences between bagging and non-bagging treatment, and also fruit quality and peel coloration characteristics at the harvest time. The pericarp at full bloom was consists of outer epidermis, hypodermis, parenchyma cell, and inner epidermis from the exterior. The cell layers from the outer epidermis to vascular bundle increased rapidly 7-10 layers to 18-26 layers from full bloom (FB) to 77 days after full bloom (DAFB) and did not change significantly until maturity. Thus, the cell division period of 'Manpungbae' pear was until 77 DAFB and during this period, the thickness from hypodermis to vascular bundle increased from $73.1{\mu}m$ to $195{\mu}m$ in this period. Stone cells were formed from seven to 21 DAFB and stone cell clusters were formed around 49 DAFB. The cork cell layer was formed between 49 and 77 DAFB. 'Manpungbae' fruit pericarp was consists of 4.5 layers of the cork cell layers and seven layers of hypodermis which has the tannin at harvest time (161 DAFB). Comparison of the fruit enlargement and fruit structure development by bagging or non-bagging showed that 'Manpungbae' fruits without bagging had more than three cork cell layer than those with bagging at maturity. The size of stone cell clusters were varied in two treatments. Fruit weight was higher in the non-bagging treatment but there was no difference in soluble solid contents (SSC) between two treatments. The weight of the 'Manpunbae' fruit was distributed from 301 g to more 900 g and the average fruit weight was 677.2 g at harvest time, and fruits in the range of 551-800 g accounted for 71.6% of total production. The SSC, acidity and SSC/acidity ratio was $10.2-12.1^{\circ}Brix$, 0.10-1.24% and 9.76-14.31 respectively, and the SSC was higher in bigger fruit which had a very higher positive correlation with a fruit weight. However, the fruit firmness tended to be lower with fruit size which had a very higher negative correlation with the fruit weight and SSC. The cork cell layer numbers between yellowish brown and green pericarp were not different significantly, in 3.8 and 3.5 respectively.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.8 no.2
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• pp.150-156
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• 2005

Purpose: We divided the children diagnosed with intususception into three different age groups and compared the clinical symptoms and treatment outcomes in order to analysis diagnosis and treatment of Intusussception. Methods: A retrospective chart review was established of 159 patients diagnosed with intussuception who had been admitted to Department of Pediatrics and General Surgery, Bundang CHA hospital from January, 2000 to May, 2004. We divided the patients into three groups, according to their age. Those who were under five months of age (group I; 21 patients), those between 5~11 months of age (group II; 61 patients), and those older than 11 months of age (group III; 77 patients). Then we compared the age, sex, seasonal distribution of occurrence, the cause, the clinical features, radiologic review, the type of intusussception, surgical methods, recurrence rate and treatment outcomes, among these three groups. Results: On comparing the clinical symptoms and signs among the three groups, the most common major clinical symptom and sign was irritabiltity in all three groups. Vomiting with irritability was statistically more common in group I (p<0.05) and bloody stool was most frequent in group III. The average time taken until a diagnosis was made after the symptom onset was, 21 hours in group I, 20 hours in group II and 22 hours in group III. Which showed no significant difference. But there was a higher rate of delayed diagnosis in group I, which took over 48 hours until the diagnosis was made (group I; 23.8%, group II; 4.9%, group III; 7.8%). Simple abdominal X-rays showed more frequent instances of intestinal obstruction in group I (p<0.05). The primary treatment done was barium enema which showed a failure rate of 52.4% in group I, 26.2% in group II and 14.3% in group III. Showing the highest failure rate in group I. Conclusion: The youngest group had vague symptoms which lead to delayed diagnosis and more frequent surgical procedures. As so, we advocate the importance of further evaluation and close observation, considering intussusception in children with symptoms of irritability and vomiting, especially in the early infant group.