• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.349-362
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• 1999

To understand the role of protozoa in the early formation of microbial fouling community, the studies on the formation of microbial film, the succession of microbial fouling communities, and the grazing pressure on bacteria population in microbial film were carried out in the laboratory, Inchon outer port and Inchon inner harbour. Bacteria and heterotrophic flagellates formed primary microbial film on the aluminum surface within 6 hours and oligotrich ciliates were observed 2 cells $mm^{-2}$ on the same surface at 9 hours in Inchon inner harbour which had physically stagnant condition. The larvaes of Balanus albicostatus which were dominant meiobenthos in Inchon coastal area attached on the glass surface at the first day of experiment. Heterotrophic flagellates showed maximum abundance of 465 cells $mm^{-2}$ at the 13rd day and ciliates showed maximum abundance of 63 cells $mm^{-2}$ at the 11st day in the Inchon inner harbour. In the Inchon outer port which opens to the outer sea, the maximum abundance of protozoa occurred at early phase, but not so many. The dominant heterotrophic flagellates were Metrornonas simplex and Bodonids. Dominant ciliates were small tintinnids and oligotrich ciliate Strombidium sp., Large Strombidium (oligotrich ciliate) and sessile Acineta turberosa (suctorian ciliate) occurred after 10 days. The attached larvae of Balanus occurred as biofouling organism on the early surface and showed maximum abundance of 18 indiv. $cm^{-2}$ at 7th day. At that time, adult barnacles were observed on the surface and dead barnacles were observed after two days. Except barnacles, the larvaes of Anthozoa sp., Oysters (Crassostrea gigas) and Polychaeta were observed on the surface from 3rd day. 3 benthic copepods including Harpacticus sp., I isopod, 1 polychaeta and 1 gastropoda were observed as predators of the microbial film on the surface after 7 days when microbial film developed very well. Although the ingestion rates of protozoa on the bactctia of the rnicrobi31 film were relatively low, the average grazing rate of protozoa on bacteria was high of 0.058 $h^{-1}$. This implied that the grazing pressure of protozoa influences the mortality of bacteria populations on the microbial film. but protozoa cannot get enough energy from only bacteria on the microbial film.

• Childhood Kidney Diseases
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• v.3 no.2
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• pp.153-160
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• 1999

Purpose : Present study was undertaken to find out significance of clinical presentation, initial laboratory data and renal biopsy findings on subsequent clinical course of IgA nephropathy in children. Methods : Clinical and laboratory data were analysed retrospectively from 60 children who have been admitted to the Pediatric Department of Kyungpook National University Hospital for the past 11 years and diagnosed as IgA nephropathy. Renal biopsy findings were graded according to the pathologic subclass proposed by Haas. Results : Pathologic grading according to Haas subclassification showed 10 cases in subclass I, 36 in II, 12 in IV and 2 in V and none in subclass II. Sex distribution showed male predominance (male to female ratio = 3 : 1) and mean age at onset of disease was $10.4{\pm}2.8$ years. Episodes of gross hematuria was seen in 71.7% and IgA level increased in 28.3% of children and these were not associated with pathologic grading nor clinical outcomes. With increasing subclass grading, serum protein and albumin decreased and 24 hours urinary protein excretion increased. Normalization of urinalysis (disappearance of hematuria) was seen in 14% at 1-2 years and 37.1% at 3-4 years of follow up period. In 3 cases, renal function deteriorated progressively and they belonged one each to the Haas subclass III, IV and V. Conclusion : In children with IgA nephropathy, progression to chronic renal failure appears to be quite high and pathologic grading according to Haas' subclassification seems to predict patient's outcome faily well. However, firm conclusion cannot be drawn from present study due to the small numbers of patients and short follow-up period. Therefore further multicenter study involving larger numbers of patients and longer periods of follow-up over 10 years was to be undertaken.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.345-359
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• 2002

The purpose of the study was to provide the fundamental data to instruct athletes through the analysis athletes' movement in javelin. Three athletes in the level of national representative were participated in this study. The study analyzed kinematic variables(lead foot and releasing javelin) through 3-D analysis and obtained the following results. 1. During withdrawal, it is important to maintain of running horizontal velocity. 2. It was showed that throng average height was $84{\pm}3.3%$ and javelin adequative degree, Among the athletes, $S_2$ who had the best record was released the javelin with the fast velocity, but throw the javelin with the less releasing velocity. 3. $S_2$ released after lead foot were completely landed and therefore it is no problem in a kinematic aspect. However, $S_1$ angle was too small. it caused increase of release velocity to be prevented. 4. $S_2$ showing the best result indicated shorter in duration time. Generally, the shorter duration time in release phase showed the longer release distance. Especially $S_1$ and $S_3$ showing the worse result indicated the longer duration time in preparatory phase, causing the breakup of force. Therefore to improve the record, it should be decreased the duration time in preparatory phase. 5. Compared with $S_1$ and $S_3$, $S_2$ showing the best record indicated the higher velocity in center of mass, trunk, upper arm, lower arm and hand That is the higher velocity of upper arm at release leaded the better velocity transfer from upper arm to following lower arm and hand, these action should be considered to be helpful of better record. According to the above conclusion, when the athletic leaders cauch athletes, they should focus on maintaining knee angle, upper body and hip angle in a previous stage of release and throwing angle, throwing height, throwing velocity in a release stage.

• Korean Journal of Applied Biomechanics
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• v.12 no.2
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• pp.17-32
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• 2002

The purpose of this study was to find the rational method to analyze golf swing with specific property of club shaft. Three subjects were filmed by two high speed digital cameras with 500 fps. The phase analyzed was downswing of each subject. The three-dimensional coordinates of the anatomical landmarks were obtained with motion analysis system Kwon3d 3.0 version and smoothed by lowpass digital filter with cutoff frequency 6Hz. From these data, kinematic and kinetic variables were calculated using Matlab(ver 5.0) The variables for this study were angular velocity and accelerations, which were calculated and following conclusions have been made : 1) Golf swing time of stiff club is faster than that of regular club. 2) In shoulder joint motion of swing with the stiff club, x-stiff showed mort rapid negative acceleration than that of regular club. 3) In regular club, the velocity of club head would be more effective velocity, which was increasing, than those of other clubs before impact. 4) In wrist joint motion of swing with stiff club, x-stiff club showed faster than regular club in the downswing and impact more rapid negative acceleration.

• Korean Journal of Weed Science
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• v.11 no.1
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• pp.50-59
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• 1991

Residual period and carry-over effect of some herbicides were determined using a bioassay method in six summer crops(potato, carrot, corn, water melon, soybean, and sesame). The effects were measured at regular time intervals after applying different rates of the herbicides. There were no great differences in residual period and carry-over injury between the soils and kinds of crops used. However, the residual period varied with the herbicides studied and the carry-over injury was dependent upon season and rate of the herbicide application, sampling depth of soil, and kind and seeding date of the test plant. When the residual herbicides were applied, the carry-over injury could be minimized by selecting tolernet crops, delaying seeding of the crops after application of the herbicides, and regulating the cultivation depth. Herbicides which showed no residual effect by the end of the cropping period(100-120 days for summer crops) and no carry-over effect were alachlor, trifluralin, ethalfluralin, metribuzin, and prometryn. When pendimethalin, metolachlor, linuron, methabenzthiazuron, and simazine were applied at the recommended rate or less, there was no carry -over injury at harvesting time. With doubling the recommended rate, however, the carry-over effect was found in sensitive crops. Napropamide applied at the rate of 300 g a.i./10 a brought about carry-over injury for Italian ryegrass and barley at 140 days in summer crops, whereas the injury was not found in Cruciferae (radish, Chinese cabbage). Nitralin applied at the rate of 150-300 g a.i./10a caused the carry-over injury for Italian ryegrass and barley at 140 days in summer crops. However, there was no injury for Cruciferae.

• Korean Journal of Weed Science
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• v.3 no.1
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• pp.57-68
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• 1983

To estimate the possible amount of weed-crop competitions under the various cropping patterns of two rice cultivars of different type, comparisons between weedy check and weed-free plots in plant height, tillering number, and plant weight were investigated. Fluctuations in Importance Value, competition value, and net productivities were used to discuss the crop-weed competition, respectively. As a result, differences in dominant weed species, competitive crop variety, most effective cropping pattern, and crop yielding characteristics under the different weed competitions were investigated, respectively.

• Journal of the Korean Vacuum Society
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• v.22 no.6
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• pp.313-320
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• 2013

The $AlAs_xSb_{1-x}$ step-graded buffer (SGB) layer was grown on the Silicon (Si) substrate to overcome lattice mismatch between Si substrate and $Al_{0.3}Ga_{0.7}As$/GaAs multiple quantum wells (MQWs). The value of root-mean-square (RMS) surface roughness for 5 nm-thick GaAs grown on $AlAs_xSb_{1-x}$ step-graded buffer layer was ~1.7 nm. $Al_{0.3}Ga_{0.7}As$/GaAs MQWs with AlAs/GaAs short period superlattice (SPS) were formed on the $AlAs_xSb_{1-x}$/Si substrate. Photoluminescence (PL) peak at 10 K for the $Al_{0.3}Ga_{0.7}As$/GaAs MQW structure showed relatively low intensity at ~813 nm. The RMS surface roughness of the $Al_{0.3}Ga_{0.7}As$/GaAs MQW structure was ~42.9 nm. The crystal defects were observed on the cross-sectional transmission electron microscope (TEM) images of the $Al_{0.3}Ga_{0.7}As$/GaAs MQW structure. The decrease of PL intensity and increase of RMS surface roughness would be due to the formation of the crystal defects.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1241-1245
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• 2006

절 성토사면에 구조물을 설치할 경우 가장 중요하게 고려되어야 하는 점은 사면의 안정성 여부이다. 특히, 절 성토사면에 설치된 구조물이 붕괴되는 가장 큰 원인은 뒷채움재 내에 존재하는 수압의 영향이라는 것을 우리는 이미 많은 연구와 경험을 통해 알고 있다. 만일 지하수위가 존재하는 상태에서 단시간에 발생되는 집중호우로 인해 수위가 갑자기 상승하였을 경우, 구조물을 통해 전혀 배수되지 않는다면 절 성토사면의 안정성은 급격히 저하될 것이다. 이러한 사면의 배수압을 소산시킬 수 있는 공법은 여러 가지가 있으나, 본 연구에서는 특히 제주도의 지역적 특성을 고려하여 화산석을 채움재로 사용한 Mattress/Filter를 절 성토사면에 설치함으로써 배수압을 소산시킬 수 있는 방법을 연구하였다. Mattress/Filter는 제방 또는 절 성토사면의 파괴와 침식을 방지하기 위해 사면에 설치하는 육각형의 철망구조로서 유연성, 다공성, 배수성 및 식생성과 같은 특징이 있으며, 콘크리트 구조물과 달리 별도의 배수시설을 필요로 하지 않는 장점이 있다. 또한 본 연구에 사용된 Mattress/Filter의 채움재인 화산석은 현재 제주도 지역에 방대하게 분포되어 있다. 특히 현무암은 제주도 암석 전체의 90%이상을 차지하고 있으며, 투수성이 매우 큰 암석이다. 현무암의 공극률은 그 종류에 따라 $0.02{\sim}0.36$의 범위로 나타난다. 특히, 표선리현무암의 경우 평균 공극률이 0.23으로 나타나 모래의 공극률인 $0.3{\sim}0.8$에 비교하여 볼 때, 연구에 사용된 재료는 아주 우수한 투수성을 가진 것으로 판명된다. 또한 현무암의 경우 암석의 겉 표면이 미세한 다공질 조직으로 이루어져 있다. 따라서 암석자체에 물이 정체될 수 있어 구조물을 통해 배수될 때 암석이 머금고 있는 물로 인해 추가적으로 발생하는 중력은 다른 재료가 가지지 못한 화산석의 또 다른 장점이라 할 수 있다.서는 자료변환 및 가공이 필요하다. 즉, 각 상습침수지구에 필요한 지형도는 국립지리원에서 제작된 1:5,000 수치지형도가 있으나 이는 자료가 방대하고 상습침수지구에 필요하지 않은 자료들을 많이 포함하고 있으므로 상습침수지구의 데이터를 인터넷을 통해 서비스하기 위해서는 많은 불필요한 레이어의 삭제, 서비스 속도를 고려한 데이터의 일반화작업, 지도의 축소.확대 등 자료제공 방식에 따른 작업 그리고 가시성을 고려한 심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴 분석기간의 주식가격정보에 의하여 최대한 발휘될 수 있음을 확인하였다.(M1), 무역적자의 폭, 산업

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1826-1831
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• 2010

This study was carried out to examine the changes of the quality feature and antioxidant activity of grape by-products. This experiment was to arrange the basic data for developing a functional material using grape by-products which were useless resources. Hot-air and freeze drying were followed by the gamma irradiation of 1~20 kGy. Hunter's color value, in case of hot-air drying, showed the highest L and a value in the 3 kGy, and it decreased according to the increase of the exposure dose. In the case of fre ze drying it showed the highest L and b value at the highest exposure, 20 kGy. It was considered that the breakdown of the pigment through high temperature processing was launched and the influence according to the gamma irradiation was not shown. The gamma irradiation of 3 kGy appeared to have a good influence on the color of the grape by-products which went through hot-air drying. The contents of the total phenolic compounds, in case of hot-air drying, showed the highest total polyphenol contents in the 3 kGy irradiation and it decreased according to the increase of the exposure dose; in contrast, the higher phenolic contents showed in the irradiated group than in the control. In case of freeze drying, the highest phenolic contents appeared in the control but 3 kGy showed the highest one in the irradiated group. Results of radical scavenging activity using DPPH and ABTS indicated that 3 kGy showed the highest radical scavenging activity in hot-air and freeze drying. Therefore, it was found that gamma irradiation of 3 kGy could improve the color and antioxidant activity of grape by-products, but an antioxidant activity of grape by-product due to the gamma irradiation was a little affected in the aspects of by-product utilization.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.1 no.1
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• pp.30-36
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• 1998

Purpose: It is well known that duodenal ulcer disease does not relapse if H. pylori is cleared from the gastric mucosa. Little is known about the recurrence of duodenal ulcer in children. The purpose of this study was to evaluate the effect of the eradication of H. pylori in duodenal ulcer in children upon the duodenal ulcer recurrence. Methods: 105 patients (M:F=78:27) diagnosed as duodenal ulcer by endoscopy in 1987~1995 were reviewed clinically, and were parted into two groups. The two treatment groups were ranitidine/antacid (RAN/ANT) and ranitidine/amoxicillin/denol (RAN/AMX/D). The latter was for H. pylori-positive children with duodenal ulcer who were diagnosed by serology and/or antral biopsies for histology, culture, and urease testing. The recurrence rates were compared between the two groups. Results: 1) 30 patients with primary duodenal ulcer underwent endoscopy for H. pylori and 27 (90.0%) of them were positive for H. pylori. 2) 27 of H. pylori-positive children received RAN/AMX/D. 23(85.2%) of them showed cure of duodenal ulcer and eradication of H. pylori. 3) The duodenal ulcer recurrence rate in RAN/ANT group was 65.3% and the rate in RAN/AMX/D was 4.3% by a year. Conclusions: There is a strong correlation between the duodenal ulceration and H. pylori infection in children, and the eradication of H. pylori in duodenal ulcer patients reduces the recurrence of the ulcer. Because of the low incidence of duodenal ulcers in children, a multicenter prospective study is required to determine the effect of treating H. pylori infetion on the long term natural history of duodenal ulcer disease.