• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.237-248
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• 2018

The vertical distribution of hydrometeor before precipitation near the cloud base has been analyzed using a scanning lidar, rawinsonde data, and Cloud-Resolving Storm Simulator (CReSS). This study mostly focuses on 13 Desember 2016 only. The typical synoptic pattern of lake-effect snowstorm induced easterly in the Yeongdong region. Clouds generated due to high temperature difference between 850 hPa and sea surface (SST) penentrated in the Yeongdong region along with northerly and northeasterly, which eventually resulted precipitation. The cloud base height before the precipitation changed from 750 m to 1,280 m, which was in agreement with that from ceilometer at Sokcho. However, ceilometer tended to detect the cloud base 50 m ~ 100 m below strong signal of lidar backscattering coefficient. As a result, the depolarization ratio increased vertically while the backscattering coefficient decreased about 1,010 m~1,200 m above the ground. Lidar signal might be interpreted to be attenuated with the penetration depth of the cloud layer with of nonspherical hydrometeor (snow, ice cloud). An increase in backscattering signal and a decrease in depolarization ratio occured in the layer of 800 to 1,010 m, probably being associated with an increase in non-spherical particles. There seemed to be a shallow liquid layer with a low depolarization ratio (<0.1) in the layer of 850~900 m. As the altitude increases in the 680 m~850 m, the backscattering coefficient and depolarization ratio increase at the same time. In this range of height, the maximum value (0.6) is displayed. Such a result can be inferred that the nonspherical hydrometeor are distributed by a low density. At this time, the depolarization ratio and the backscattering coefficient did not increase under observed melting layer of 680 m. The lidar has a disadvantage that it is difficult for its beam to penetrate deep into clouds due to attenuation problem. However it is promising to distinguish hydrometeor morphology by utilizing the depolarization ratio and the backscattering coefficient, since its vertical high resolution (2.5 m) enable us to analyze detailed cloud microphysics. It would contribute to understanding cloud microphysics of cold clouds and snowfall when remote sensings including lidar, radar, and in-situ measurements could be timely utilized altogether.

• Journal of Bio-Environment Control
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• v.23 no.3
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• pp.229-234
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• 2014

We analyzed drainage water from coir substrate in which cucumber plants were grown in winter and elucidated changes in pH, EC, and major nutrients according to the growth stages to recommend nutrient solution management appropriate to each growth stage. From the analysis of drainage solution the growth stages of cucumber were desirable to be divided into two, planting to fruit setting and fruit setting to harvest in case of nutrient solution management. The time required was about 3 weeks from planting to the first fruit setting and thereafter 7~10 days more until the first harvest. Approximately every 3~4 days were needed until the upper flowers bloomed. The time required from fruit setting to harvest was not different much among flowers as cucumber plants grew. From the experimental results, EC of supplied solution was recommended to maintain a little high to $3.0dS{\cdot}m^{-1}$ until before fruit setting and lower a little to $2.0{\sim}2.3dS{\cdot}m^{-1}$ after that. Of course, the amount of solution supply should be increased as plants grew. In case of each nutrients, the recommendation of concentrations of nitrogen, phosphorus and calcium were 700, 60, and $110mg{\cdot}L^{-1}$ each until before fruit setting, and then 660, 50, and $100mg{\cdot}L^{-1}$ each after fruit setting. The concentrations of potassium and magnesium are recommended to start from 400 and $80mg{\cdot}L^{-1}$ until fruit setting and lower a little after that.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.721-728
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• 2008

DBPs(Disinfection By-Products) are most formed through the reactions between chlorine and NOM(Natural Organic Matter) in water treatment. In this study, occurrence of DBPs including THMs(Trihalomethanes) is evaluated. Also, influencing factors by the seasons and raw water quality were investigated for correlation among them and the characteristics of THMs formation by prechlorination process. This study investigated the operation condition for THMs removal depending on raw water quality. Water treatment plant from intake station to gauging well flows for about 10 hours in Y Water Supply Office. It is limited to control of THMs formation because of excessive reaction time between chlorine and THMs precursors in the intake station. Therefore, as multi-points prechlorination from intake station to gauging well, THMs formation was decreased in the water treatment, and it was willing to prevent overdosage of chlorine. The concentration of THMs was 0.021 mg/L in the summer, 0.015 mg/L in the winter, respectively. Also, THMs formation showed that 0.013 mg/L in the water of gauging well after prechlorination, 0.014 mg/L in the flocculation/sedimentation/filtration, 0.016 mg/L in the water after postchlorination, respectively. THMFP(Trihalomethane Formation Potential) removed 42.7% and 50% through the flocculation/sedimentation and filtration, respectively, and it is similar TOC removal efficiency. In this study, multi-points prechlorination from intake station to gauging well decreases in contact time and concencrations of NOM and chlorine. Also, it decreases in THMs and amount of chlorine uesd. In the result of multi-points prechlorination in the summer, the concentration of THMs was 0.013mg/L in the treated water. In view of these facts, THMs formation can be decreased approximately 50%.

• 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.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.100-112
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• 2005

Soil temperature was measured from the surface to 40 cm depth at three stations with different heights in tidal flat of Gomso Bay, west coast of Korea, for one month in every season 2004 to examine the thermal structure and the variation. Mean temperature in surface layer was higher in summer and lower in winter than in lower layer, reflecting the seasonal variation of vertically propagating structure of temperature by heating and cooling from the tidal flat surface. Standard deviation of temperature decreased from the surface to lower layer. Periodic variations of solar radiation energy and tide mainly caused short term variation of soil temperature, which was also intermittently influenced by precipitation and wind. Time series analysis showed the power spectral energy peaks at the periods of 24, 12 and 8 hours, and the strongest peak appeared at 24 hour period. These peaks can be interpreted as temperature waves forced by variations of solar radiation, diurnal tide and interaction of both variations, respectively. EOF analysis showed that the first and the second modes resolved 96% of variation of vertical temperature structure. The first mode was interpreted as the heating antl cooling from tidal flat surface and the second mode as the effect of phase lag produced by temperature wave propagation in the soil. The phase of heat transfer by 24 hour period wave, analyzed by cross spectrum, showed that mean phase difference of the temperature wave increased almost linearly with the soil depth. The time lags by the phase difference from surface to 10, 20 and 40cm were 3.2,6.5 and 9.8 hours, respectively. Vertical thermal diffusivity of temperature wave of 24 hour period was estimated using one dimensional thermal diffusion model. Average diffusivity over the soil depths and seasons resulted in $0.70{\times}10^{-6}m^2/s$ at the middle station and $0.57{\times}10^{-6}m^2/s$ at the lowest station. The depth-averaged diffusivity was large in spring and small in summer and the seasonal mean diffusivity vertically increased from 2 cm to 10 cm and decreased from 10 cm to 40 cm. Thermal propagation speeds were estimated by $8.75{\times}10^{-4}cm/s,\;3.8{\times}10{-4}cm/s,\;and\;1.7{\times}10^{-4}cm/s$ from 2 cm to 10 cm, 20 cm and 40 cm, respectively, indicating the speed reduction with depth increasing from the surface.

• Journal of agricultural medicine and community health
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• v.4 no.1
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• pp.41-61
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• 1979

Two interview surveys (1976 for 800 patients, 1978 for 200 patients) and an inventory survey through medical records(1978) for epileptic patients who have registered with the Korean Epilepsy Association (Rose Club) since 1971 were carried out by trained health workers in advance of survey. The data obtained from the analysis showed as follows: 1) 35.2% of patients were born in Seoul and 70. 6% of patients born elsewhere have lived in Seoul. 2) 50-60% of patients were 15-30 years cid. 3) 33.4%, 24,6 and 24.6 of all pupils and students went to elementary, junior and senior high schools respectively. 4) 21.2% of all pupils and students had dropped out of school and 51.4% of them were away from school because of epilepsy. 5) 3.1% of all patients had no job at all and students comprised 20.9% of patients followed by clerical work, commercial business and farming with about 6% in each group.6) Reasons given for unemployment such as dismissal (4.3%), quit (27.7%), hesitation to employ (42.5%)and discontinuance of job (25.5%) were basically due to epilepsy. 7) About half(46.2%) of all patients have become Christian since the Rose Club was a voluntary agency which has been sponsored by Christians. 8) 82. 6% of patients were diagnosed as having grand mal as the most. 9) 29.4% of patients explained aura with psychomotor disturbances and 13.8% with sensory disorders. 10) 46.3% of patients were attacked with seizures when they were tired and others(11.6% and 4.9%) after excessive eating and hunger. 11) Patients suffered more seizures in spring and summer rather than in autumn and winter and most patients had attacks 1-5 times a month. 12) For etiologic reasons of epilepsy, 35.5% of patients considered it was caused by psychological stress and 11.5% by trauma. Only 1.1% of patients considered it as having hereditary components. 13) 51% of patients were slow in caring for their own illnesses. They started to reat epilepsy after spending 5 years of time from the initial seizure. Only 5.4% of patients had received the modern anti-epileptic therapy right after the nitial seizure. 14) 62.1% of patients had no therapy or irregular or incomplete treatment before registration at the Rose Club Clinic. 15) Before registration at the Rose Club, 42.4% of patients received medical care. On the other hand, 25.6% went to herb doctors and 12.5% used to go to the drugstore in order to get anti-epileptic drugs. 16) 41. 6% of patients who took anti-epileptic drugs had more or less side-effects. Indigestion was the most common. 17) For continuation of treatment, 30.3% have received treatment for more than 5 years and the evident showed that epilepsy took a longer time to be cured. 18) Regarding the medical care received 44.2% of patients were very satisfied with effective care and 26.5% felt as good. 19) For attitudes toward epilepsy. 27.0% of patients and 68.2% of patients family were pessimistic. 20) 65.9% of patients had optimistic attitudes toward effectiveness of medical care of epilepsy. 21) 64.8% of wives and husbands had better understanding and cooperative for their spouses who had epilepsy. 22) 33.3% of patients were under-treated at the place of work. 23) 70.2% of patients wished to marry when they reach childbearing age and 63% wished to have children. Through the above results it is recommended for nation-wide epilepsy control that the sound and correct health education not only from health aspect but also from welfare aspect should be planned and implemented as soon as possible.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.209-215
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• 1990

Some preliminary studies were conducted to find out whether the levee-burning could justifiable for the suppression of insect pests, particularly the smaller brown planthopper (Laodelphax striatellus F.). Density surveys on pests and their enemies (mostly spiders) were carried out upto the mid May at an experimental paddy field located in Suwon after of it's levee $(72\times1m)$ was burned on Feb. 20, 1987. Results were discussed in relation to density recovering of both pests and their possible enemies (spiders) and summarized as below. Not a single individual of any pest or enemy was found from the levee upto sometime after the levee-burning. Grasses started to grow more vigorously in burned ares than in unburned upto about 60 days after the burning. And densities of both pest and enemies grew higher in burned areas than in unburned from about 75 days after the burning (in Early may). It is suspected that all individuals of pests and enemies fond from the burned areas could have immigrated from the surrounding areas. If levee-burning was carried out in much wider areas, much longer time would be needed to recover the density of both pests and enemies to the center region of the burning. Wingless spiders would require even longer time than winged pest species to re-establish in the center region of the widely burned field. Pirata subpiraticus, the most abundant spider species in Korean paddy fields, starts to move about and searches for food at above $9^{\circ}C$ which is somewhat lower than the critical temperature for the pest species. Thus P. subpiraticus would require more food than other pest species early in the spring, and therefore, it would have lower probability to survive than pest species particularly in burned areas. Experiments for pest suppression with levee-burning would better be carried on in much wider areas, and its justification seems to be discussed after man other disciplines related to both pests and their natural enemies were throughly studied together with their density surveys. However, according to the present point of vie, the opinion that levee-burning is helpful for controlling pests which over winter on levee areas could not be justifiable.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.87-90
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• 2013

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. Due to climate change, the occurrence of abnormal weather conditions has become more frequent, causing damage to vegetable crops grown in Korea. Hot pepper, chinese cabbage and radish, the three most popular vegetables in Korea, are produced more in the field than in the greenhouse. It has been a trend that the time for field transplanting of seedlings is getting earlier and earlier as the spring temperatures keep rising. Seedlings transplanted too early in the spring take a longer time to resume the normal growth, because they are exposed to suboptimal temperature conditions. This experiment was carried out to figure out the change of cellular tissue of chinese cabbage under the condition of low temperature to provide the information regarding the coming climatic change, on the performance of 'Chunkwang' chinese cabbage during the spring growing season. In our study, plant height, number of leaf, chlorophyll and leaf area was lower at the open field cultivation than heating house treatment after transplanting 50 days. Especially in fresh weight, compared with heating treatment, open field and not heated treatment were notably low with the 1/3 level. Of damage symptoms due to low temperature cabbage leaves about 10 sheets when $-3.0^{\circ}C$ conditions in chinese cabbage was a little bit of water soaking symptoms on the leaves. $-7.4^{\circ}C$ under increasingly severe water soaking symptoms of leaf turns yellow was dry. Microscopy results showed symptoms of $-3.0^{\circ}C$ when the mesophyll cell of palisade tissue and spongy tissue collapse, $-7.4^{\circ}C$ palisade tissue and spongy tissue was completely collapsed. The result of this study suggests that the growers should be cautioned not to transplant their chinese cabbage seedlings too early into the field, and should be re-transplanting or transplanting other plants if chinese cabbage are exposed to suboptimal temperature conditions ($-3.0^{\circ}C$ or $-7.4^{\circ}C$).

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.769-782
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• 2002

Three kinds of green forages(rye, oats and mixed forages) was harvested and mixed with rice straw, wheat bran and 2 grains(corn and soybean), which harvested 2 different dates(common harvesting dates, 7 days early to common harvesting dates). And each mixture was ensiled in 6 poly vinyl chlorides that was 60 liter, immediately. They were opened at 0, 5, 10, 25, 35, 60 and 100 days after ensiling for chemical analysis. And its effects of those TMFFs on feed values were observed. Average contents of water, crude protein, ADF, NDF, Ca and P of formulated TMFs were 72 to 75%, 14.75 to 18.24, 12.47 to 19.07, 39.82 to 47.01, 0.99 to 1.07 and 0.38 to respectively. Crude protein content was the highest in the mixed forages-TMFF and the lowest in the rye-TMFF. The ADF and NDF contents of rye-TMFF were higher than orthers. And CP, ADF, NDF, TDN, P and Ca contents were no significant difference among treatments regardless of storage period and harvest time, but all treatments indicated good quality. Intenal temperatures of TMFF were shown to be 1 to 5$^{\circ}C$ higher than ambient temperatures. The temperature of the Oat-TMFF formulated during winter sustained higher to the level of 6${\sim}$9$^{\circ}C$ for 10 days. The pH of TMFF were 4.0 to 4.2 and the content of $NH_3$-N was shown to be 7.79 to 8.23mg/$d{\ell}$. In the VFA contents, any tendency was not shown at all treatments depending on harvest time. Even though rye-TMFF showed the lowest VFA value. At all treatments except rye-TMFF, propionate production was increased and stable after 25 days of storage. Digestibility of rice straw from TMFF on DM basis was 15${\sim}$20% higher compared with non-treated rice straw.

• Journal of Embryo Transfer
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• v.18 no.2
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• pp.97-108
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• 2003

In-vitro fertilized Hanwoo embryos were biopsied for sex determination by PCR. Biopsied embryos were incubated for 1∼2 hours for the recovery. Those sexed Hanwoo embryos were transferred to 49 Hanwoo and 16 Holstein recipients from February 2000 to February 2001. Of 65 recipients, 14 cows(12 Hanwoo and 2 Holstein) delivered the same offspring as sex-determined by PCR, therefore the conception rate was 21.5%. 1. Total 65 embryos(male 35, female 30) were transferred to recipients, and 14 calves (male 6, female 8) were delivered. In comparison between sex by PCR method and sex of calves born after embryo transfer, the accuracy of sex determination was 100.0%. 2. The conception rate after transfer with biopsied embryo between Hanwoo and Holstein was 24.5% and 12.5% 3. The conception rate after transfer with biopsied embryo between fresh and frozen-thawed embryos was 23.5% and 14.3%. 4. The conception rate according to the season when embryo was transferred was 11.8, 29.4, 23.5 and 20.0% for spring, summer, autumn and winter, respectively. 5. The conception rate according to embryo quality after biopsy was 41.7, 30.0 and 0.0% for excellent, good and fair quality. 6. The conception rate according to thickness of uterine horn was 71.4, 18.9, 11.8 and 0.0% for 0, +, ++ and +++ thickness. 7. The conception rate according to the site in the uterine hem where embryo was put was 30.0, 20.0 and 10.0% for cranial, mid, and caudal part of uterine horn. 8. The conception rate according to the quality of corpus luteum ipsilateral to the uterine horn where embryos was transferred was 41.2, 14.3 and 15.4% for excellent, good and fair quality. 9. The conception rate according to the time required for embryo transfer was 18.2, 30.0, 30.0, 0.0 and 25.0% for 10, 15, 20, 25 and 30 minutes. 10. The conception rate according to parity of recipients was 26.5, 19.1, 14.3 and 0.0% for the primiparous, the 2nd parous, the 3rd parous and the 4th parous recipients. These results indicated that fresh embryos are more demanded than frozen-thawed embryos for good conception rate in embryo transfer with biopsied-sexed embryo. Also, it was indicated that we should consider embryo-recovering condition, recipient's uterine thickness, transfer site in uterine horn, quality of corpus luteum, time required for transfer and parity of recipient to achieve good conception rate in ET with biopsied-sexed embryos.