• 한국지능시스템학회논문지
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• 제20권2호
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• pp.189-194
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• 2010

사용자들의 추천 서비스를 위해 다른 사용자들의 평가값을 이용하여 특정 사용자에게 서비스를 추천해 주는 추천 시스템은 협력적 필터링 방법을 널리 사용되고 있다. 하지만 이러한 추천시스템은 클러스터링 과정에서 이미 분류된 그룹에 특정 사용자가 분류되어 정확히 분류되지 못하고, 사용자들의 평가값 오차가 클 경우 정확하지 못한 결과를 추천할 수 있다. 본 논문에서는 예측 정확도를 높이기 위하여 특정 사용자의 분류 항목을 기준으로 재분류하고, 시간적으로 임계치를 넘어 선 사용자의 평가값을 찾아내어 보정한 후 협력적 필터링에 적용한 추천 시스템을 제안하였다. 본 시스템에서는 클러스터링 과정에서 이미 분류된 그룹에 특정 사용자를 분류하는 것이 아니라, 특정 사용자를 기준으로 그룹을 재편성하는 방법을 사용하였다. 또한 평가 정보를 표본 절사평균에서 하위 10%를 절사하여 평가 정보들을 보정하고, 나머지 자료들은 시간에 따른 가중치를 적용하였다. 실험 결과 제안한 방법은 일반적인 협력적 필터링보다 MAE를 사용할 경우 예측 정확도가 14.9% 정도 우수함을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제30권10호
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• pp.1425-1434
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• 2017

Objective: The main objective of this study was to determine the effect of different diets for early-weaned (EW) calves on rumen development, and how this affects fat deposition in the longissimus dorsi of adult Korean Hanwoo beef cattle. Methods: Three EW groups were established (each n = 12) in which two- week-old Hanwoo calves were fed for ten weeks with milk replacer+concentrate (T1), milk replacer+concentrate+roughage (T2), or milk replacer+concentrate+30% starch (T3); a control group (n = 12) was weaned as normal. At six months, 5 calves of each group were slaughtered and their organs were assessed and rumen papillae growth rates were measured. The remaining calves (n = 7 in each group) were raised to 20 months for further analysis. Results: Twenty-month-old EW calves had a higher body weight (BW), backfat thickness (BF), longissimus dorsi muscle area (LMA) and intramuscular fat (IMF) than the control (p<0.05). Organ growth, rumen histology, and gene expression patterns in the 6-month-old calves were positively related to the development of marbling in the loin, as assessed by ultrasound analysis (p<0.05). In the group fed the starch-enriched diet (T3), higher BW, BF, LMA, and IMF were present. The IMF beef quality score of 20-month-old cattle was 1+ for the T2 and T3 diets and 1 for the T1 diet (p<0.05). Conclusion: Papillae development was significantly greater in calves fed on high-concentrate diets and this may have resulted in the improved beef quality in the EW dietary groups compared to the control.

• 한국정보과학회논문지:시스템및이론
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• 제30권12호
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• pp.756-771
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• 2003

효율적인 동영상 검색 방법은 많은 양의 동영상 데이터를 관리하는 디지털 비디오 라이브러리 시스템에서 필수적으로 요구되는 기능이다. 본 논문에서는 샷 단위 동영상을 문맥, 전경, 배경, 오디오로 나누어 비교하여 질의 동영상과 비슷한 동영상을 찾아내는 예제 기반 동영상 검색 알고리즘을 제안하였고, 제안한 알고리즘에 따라서 저작 및 검색도구를 구현하였다. 샷간의 관계 정보 즉, 문맥을 고려한다는 것은 인접한 샷들 간의 오디오, 움직임 정보들과 같은 저급 수준 내용 정보 간에 변화 패턴을 비교한다는 것이다. 두 번째 비교 요소인 전경은 움직이는 객체들의 집합을 의미하고, 세 번째 비교 요소인 배경은 전경을 제외한 나머지 비디오 정보를 의미한다. 이러한 비교 방법은 동영상 제작 과정에 근거한 것으로써 사용자로 하여금 직관적인 비교를 할 수 있게 한다. 또한 질의 신을 직접 구성할 수 있게 하였고, 각각의 비교요소에 가중치를 부여할 수 있도록 하여서 사용자의 검색의도를 자유롭게 반영할 수 있도록 하였다. 본 논문에서는 동영상이 가지고 있는 의미 정보를 검색에 완전히 반영하지는 못하지만, 문맥을 통해서 부분적인 의미 정보를 사용할 수 있도록 하였으며, 질의 신 구성과 직관적인 비교 요소를 사용함으로써 사용자의 검색 의도를 최대한 반영하고자 하였다.

• Toxicological Research
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• 제8권2호
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• pp.235-253
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• 1992

A subacute toxicity study of cis-Malonato[(4R,5R)-4,5-bis(aminomethyl)-2-isopropyl-1,3-dioxolane]platinum(II)(SKI 2053R) was carried out to obtain information on its toxicological profiles, and to determine the maximum tolerated dose in beagle dogs. Four groups of beagle dogs (2M and 2F per group, 0,0.5,1.0,2.0mg/kg/day)were given 15 i.v. injections of SKI 2053R. In order to compare the toxic effects of SKI 2053R with those of cisplatin, one group was treated with cisplatin(0.7mg/kg/day)according to the same treatment schedule. The dosing schedule was divided into 3 courses of 5 consecutive days with 23-day dose-free intervals between each course. After completion of the treatments, remaining dogs were necropsied under established guidelines. Three of four dogs in the high dose group and one of four dogs in the middle dose group treated with SKI 2053R died of hypovolemic shock secondary to hemorrhagic and ulcerative enterocolitis. No toxicity-related mortality occurred in the low dose group of SKI 2053R. No survivor was observed in the group of cisplatin. Clinical signs including vomiting, diarrhea, anorexia and loss body weight were apparent in dogs given either cisplatin or high and middle doses of SKI 2053R. Severe thrombocytopenia and leukocytopenia were observed in the high dose group of SKI 2053R and cisplatin-treatment group, while toxicities as bone marrow suppression were reversible. The significant elevation of serum ALP values in group of SKI 2053R(2.0 mg/kg/day and 1.0mg/kg/day) and cisplatin(0.7mg/kg/day)was observed. Slight proteinuria waa observed in high and middle dose level groups of SKI 2053R. In histopathological examinations, pathological alterations of liver, kidney and spleen were noted dose-dependantly in dogs treated with SKI 2053R, and there was no overt sign of toxicity in low dose group of SKI 2053R. Compared to SKI 2053R, more severe durg-related toxicities occurred in dogs treated with cisplatin. It waw estimated that maximum tolerated dose of SKI 2053R in this treatment schedule was 0.5~0.7mg/kg/day. In conclusion, overall toxic potential of SKI 2053R was approximately 3 times lower than that of cisplatin with respect of lethality.

• The Korean Journal of Pain
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• 제12권1호
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• pp.36-42
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• 1999

Background: The current maximal recommended doses of lidocaine are 7 mg/kg with $5\;{\mu}g/ml$ of epinephrine. But in clinical practice, sometimes more doses of lidocaine are required to produce adequate regional anesthesia. Method: Twenty-two healthy women patients were divided into two groups and pretreated with valium 5 mg p.o., morphine 5 mg i.m., and midazolam 2 mg i.v. before operation. Of these, 7 mg/kg of 2% lidocaine with $5\;{\mu}g/ml$ of epinephrine were given to 11 patients epidurally. Initial 3 ml of epinephrine mixed lidocaine was given as a test dose and remaining doses were given 5 ml/30 sec with 3 min intervals. Radial arterial blood were drawn at 5, 10, 15, 20, 30, 45, 60, 90, 120 min to measure plasma lidocaine concentrations. After confirming all of the peak plasma concentrations of 7 mg/kg lidocaine were absolutely under $5\;{\mu}g/ml$, the other 11 patients were given 10 mg/kg of 2% lidocaine with $5\;{\mu}g/ml$ of epinephrine epidurally and blood samplings were taken according to the same method of 7 mg/kg group. The peak plasma concentration ($C_{max}$), time to reach to $C_{max}$ ($T_{max}$), time to reach to $T_4$, maximal sensory block level, systemic toxicity, and vital sign changes were investigated. Result: $C_{max}$ was significantly higher in 10 mg/kg group ($5.1{\pm}1.3\;{\mu}g/ml$) than 7 mg/kg group($3.3{\pm}0.5\;{\mu}g/ml$), but $T_{max}$ ($10.5{\pm}2.7$ min vs $10.9{\pm}3.1$ min) was not different. Time to reach $T_4$ was significantly shorter in 10 mg/kg group ($9.5{\pm}2.7$ min) than 7 mg/kg group ($12.7{\pm}3.2$ min) but maximal sensory block level ($T_{3.7{\pm}0.7}$ vs $T_{2.7{\pm}1.0}$) was not different. In four patients of 10 mg/kg group, peak plasma concentrations exceeded $5\;{\mu}g/ml$, but no systemic toxicities appeared. No significant vital sign changes were observed. Conclusion: The current maximal recommended doses of lidocaine, merely based on body weight are not always appropriate. Further studies are needed to determine more precise guideline of maximal doses that include various pharmacokinetic components.

• 한국임상수의학회지
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• 제28권3호
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• pp.310-313
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• 2011

6년령 암컷 시츄견이 체중 부하하는 파행을 동반한 좌측 앞다리굽이관절 주위의 종괴를 주증으로 충북대학교 동물의료센터에 내원하였다. 초음파 검사결과 피막에 싸인 고에코성의 종괴가 앞다리굽이관절에서 확인되었으며, 방사선학적 검사 결과 흉부나 복부로의 전이 소견은 관찰되지 않았다. Gun-biopsy 샘플을 이용한 세포학적 검사 결과 세포부동증, 다형성 등 악성의 지표를 보이는 종양세포들이 다수 확인되었으며, 치료를 위하여 좌측 전지의 절단술이 시행되었다. 절제된 조직의 조직병리학적 검사 결과 악성 말초 신경집종으로 진단되었다. 환자는 수술 후 보행이나 전신활력 등이 양호하였으나 술 후 5개월째에 좌측 전지 절단술을 시행했던 부위의 피하 종괴와 다른 두 곳의 피부 종괴가 발생하였다. 종괴는 수술적으로 제거되었으며, 절제된 조직의 세포학적 검사 결과 원발 종양과 유사한 소견으로 종양이 재발되었음이 확인되었다. 술 후 종양의 또 다른 재발을 막고 의심되는 폐 전이의 속도를 늦추기 위한 목적으로 cyclophosphamide와 piroxica을 병용한 화학요법이 시행되었다. 첫 수술로부터 26개월이 경과한 현재 환자는 만족할만한 삶의 질을 유지하며 생존하고 있다. 개의 악성 말초 신경집 종양에서 적극적인 외과적 절제와 metronomic chemotherapy의 병행은 효과적인 치료법이 될 수 있다.

• Journal of Periodontal and Implant Science
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• 제28권2호
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• pp.351-372
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• 1998

The purpose of this study was to evaluate in vitro effects of the loss of tooth substance and root surface changes following root planing with various periodontal instruments. The 39 extracted human teeth due to severe periodontal disease were included. The total 50 root surfaces of 30 teeth were root planed with following instruments : Group 1, with Gracey curette, Group 2, with ultrasonic scaler, Group 3, with rotating root planing bur, Group 4, with Gracey curette plus rubber cup polishing, and Group 5, with ultrasonic scaler plus rubber cup polishing. Following root planing, the amount of tooth substance loss was evaluated by measuring the weight of the removed tooth substance and then 5 specimens ($5{\times}5{\times}2mm$) were randomly selected from the each group for roughness measurement. Root planed areas of each specimen were subjected to five measurements using the Profilometer and an average surface roughness values(Ra) for each group was obtained. Statistical difference for roughness values of each group was analyzed using oneway ANOVA and student t-test. For scanning electron microscopic(SEM) examination of root surface changes following root planing, 15 root surfaces of remaining 9 teeth were root planed and 3 specimens were randomly selected. The mean loss of tooth substance removed was Group 1, $7.0{\pm}1.09mg$, Group 2, $1.3{\pm}1.00mg$, Group 3, $5.8{\pm}1.72mg$, Group 4, $8.7{\pm}1.34mg$, and Group 5, $4.5{\pm}1.68mg$ following root palning, respectively. These results indicate that curette is effective instrument in the respect of diseased root substance removal. The average surface roughness values are following results : Group 1 and Group 4 were the smoothest surface ($Ra=0.34{\pm}0.06{\mu}m$, $Ra=0.34{\pm}0.04{\mu}m$, respectively) and Group 2 was the roughest surface ($Ra=2.09{\pm}0.06{\mu}m$). Statistical analysis of roughness values demonstrated a highly significant difference (P<0.05) between each experimental groups. However, no statistically significant difference in roughness values were observed between the Group 1 and Group 4. The results in this study suggest that curette and/or polishing procedure should be done after root planing with ultrasonic scaler and caution should be used with dia-mond-coated bur during routine root planing procedure.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1993년도 제27차 학술대회 초록집
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• pp.100-100
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• 1993

구개인두성형술은 만성 코골음 및 폐쇄성 수면 무호흡증의 치료를 위해 널리 이용되고 있는 수술이며 수술 직후의 치료 효과 및 합병증에 대한 연구는 많이 이루어져 있으나 5년 이상의 장기 추적 관찰에 관한 연구는 드물게 보고 되고 있다. 이에 저자들은 1985년부터 1987년까지 구개인두성형술을 시행한 총 37명의 환자중 추적관찰이 가능했던 25명의 환자(남:18명, 여:7명)를 대상으로 수술전, 수술후 8주 및 수술후 5년이 지난 환자의 주관적 증상을 비교 평가 하였으며 중상의 변화와 함께 체중의 증감도 같이 조사하여 다음과 같은 결과를 얻었다. (1) 수술후 5년된 25명의 환자에서 코골음은 10명(40%)에서 완전히 사라졌고 정도의 차이(Grade 1 - 3)는 있지만 3명을 제외한 나머지 모두에서 호전을 보였다. (2) 수술전 AI>20이었던 15명의 환자에서 발견된 수면 무호흡증은 추적 관찰용 수면 다원 검사상 13명의 환자에서 Grade 0 - 1 (Oxygen saturation 86%)로의 호전을 보였고 수술후 5년이 지난뒤에도 증상의 변화 및 체중 변화는 없었다. (3) 수술 5년후에도 문제가 되는 합병증으로는 물을 급히 마실 때에만 코끝에 물방울이 비치는 정도의 구개인두부전 3례, 인두 비대칭 1례, 인두 건조감이 5례에서 관찰되었다. 그외 비인두 협착, 미각 상실, 및 호흡 순환계의 장애 둥 심각한 합병증은 발견되지 않았다.

• 대한치과보철학회지
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• 제44권1호
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• pp.124-134
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• 2006

Statement of problem: Streptococcus produces energy and forms extracellular polysaccharides by metabolizing sucrose. Insoluble glucan, a kind of extracellular polysaccharide, is the important material of dental plaque. Fructose affects the metabolism of sucrose. Purpose: The purpose of this study was to evaluate the effect of fructose on the metabolism of sucrose in Streptococcus mutans. Materials and methods: To determine the effect of fructose on the formation of artificial plaque by Streptococcus mutans Ingbritt, S. mutans and fructose were placed in beakers containing M17 broth and sucrose. The wires were hung on frameworks inserted into cork stoppers, and then immersed in each of the beakers. After the incubation with gentle shaking, each wire was weighed. To analyze the effect of fructose on the sucrose metabolism by S. mutans or glucosyltransferase, S. mutans and fructose were placed in M17 broth containing sucrose. After the incubation. the remaining sucrose and polymers were analysed by thin layer chromatography. Results: The following results were obtained; 1. When Streptococcus mutans was cultured in the media containing 3% sucrose for 8 hours, the mean weight of formed artificial plaque on the wires was $124.3{\pm}3.0mg$, whereas being reduced to $20.7{\pm}10.2mg$ in the media added with 3% sucrose and 4% fructose(p<0.05) 2. When the control containing glucose was added with sucrose, the optical density of Streptococcus mutans solution cultured for 24 hours was not increased compared with the control, while being increased by adding with fructose. 3. When Streptococcus mutans was incubated in the media added with sucrose and fructose for 8 hours, the number of viable cells was increased compared with the media added with sucrose. 4. The amount of remained sucrose was increased in Streptococcus mutans culture supernatant of media added with sucrose and fructose than with sucrose only. but the amount of produced insoluble glucan was decreased. 5. The amounts of remained sucrose and produced soluble glucan were increased in the culture of glucosyltransferase-contained media added with sucrose and fructose than with sucrose only, but the amount of produced insoluble glucan was decreased . Conclusion: These results indicated that the sucrose metabolism and the production of insoluble glucan were inhibited in Streptococcus mutans by adding fructose in the media containing sucrose.

• The Korean Journal of Physiology
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• 제5권1호
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• pp.59-69
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• 1971

Studies were undertaken on the changes in the renal blood flow by relating them with the alterations in the amplitudes in the rheogram of rabbits. The changing pattern of the electrical conductivity was recorded by means of the needle electrodes inserted into the kidney and the surrounding aluminium foil which was grounded. The Impedance Rheograph manufactured by the Narco Company was used. The small artifact which persisted after ligation of the renal vessels was subtracted from the value obtained in each pulsatile wave in the rheogram. The animals were nembutalized intravenously, 30 mg/kg. A plastic canule was inserted into the carotid artery and the arterial blood pressure was monitored continuously with the pressure transducer connected to the physiograph. Stepwise bleedings were performed on the animal. The first bleeding was between 13 to 18 ml in the amount, and it was folowed by consecutive hemorrhages, 5 or 10 ml each time. The total amount of bleeding was summed as much as 1.5-2% of the body weight. Two minutes fter each bleeding th arterial blood pressure, ECG and the rheogram were taken. That was the necessary time to obtain the stabilized picture of each parameter. After closing the bleeding process, the shed blood was retransfused into the animal and the response in the renal blood flow was observed as well as the arterial blood pressure. Particularly the presence or absence of the autoregulatory mechanism in the situation of the hemorrhage was also studied. The results obtained were as follows: 1. In 7 cases out of 22, that was about one third of the total number of experiments, the autoregulatory mechanism of the renal blood flow persisted even in acute hemorrhage, and the decreases in the renal blood flow were less than 10% of the control values even when the arterial blood pressure dropped to 66-87% of the original value obtained before the bleeding. 2. Because of the stepwise bleeding the exact blood pressure at which the renal blood flow reduced as much as one third of the control value could not be obtained. However, the results revealed that the approximate pressure, expressed as percentage of the control value, was 50-60% in 3 cases, 61-70% in 4 cases and 71-80% in 8 cases. In one case the decrease in the renal blood flow exceeded one third of the control value before the pressure dropped to 80% of the control. 3. In 19 cases the decreases in the renal blood flow exceeded one half of the control values by hemorrhage. Then the arterial blood pressure revealed less than 40% of the control value in 6-cases. In 2 cases the pressure was 51-60% of the control pressure. In 5 cases the range of bleed pressure was 61-70%, and in e remaining 6 cases the pressure ranged from 71 to 80% of e control value. 4. Out of 15 cases of retransfusion after definite decreases in the renal blood flow loller·ing the hemorrhage, 9 cases restored their renal blood flow. On the contrary 6 cases showed low values even when the shed blood was retransfused. 5. Theories concerning the mechanism of the autoregulation of the renal blood flow were reviewed for the purpose of explanation of the results obtained. However, there are much to be done before greater satisfaction