• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.244-247
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• 2008

The phenomena of oil whip in steam turbine takes place for the un-balancing force between rotor shaft and bearing oil film. The several parameters that affect onset of oil whip have been well known. However, the major parameter of oil whip is shaft mis-alinement. A oil whip causes the high vibration and the shutdown of rotor system. We mostly stop the steam turbine to adjust a shaft re-alinement concerning oil whip. In this case, It needs many costs for maintenance and long shutdown times. In this study, we study and observe the oil whip of the 300MW steam turbine in many years and we conduct the field test for another steam turbine for reducing vibration from oil whip. The results of this study are that a oil whip takes place with a particular rotating speed or a particular turbine output and the oil temperature change is a very effective method for on-line oil whip treatment.

• 한국항행학회논문지
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• 제16권1호
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• pp.35-40
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• 2012

본 논문에서는 선박 통신용 HF 휩 안테나의 소형화 방법을 제안한다. HF 휩 안테나의 크기를 줄이기 위해 선형 휩 안테나의 끝 부분을 헬리컬 형태로 변형하였다. 상용 휩 안테나에 비해 60% 정도의 크기를 갖는 휩 안테나를 설계하였고, 상용의 휩 안테나와 변형된 휩 안테나를 사용한 통신실험을 수행하였다. 실험을 통해 제안하는 휩 안테나가 선박 통신용 상용 휩 안테나를 대체할 수 있음을 확인하였다.

• 플랜트 저널
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• 제4권4호
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• pp.56-61
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• 2008

The phenomena of oil whip in steam turbines take place for the unbalance force between a rotor shaft and bearing oil film. The several parameters that affect onset of oil whip have been well known. However, the major parameter of oil whip is shaft mis-alinement. A oil whip causes the high vibration and the shutdown of rotor system. We mostly stop the steam turbine to adjust a shaft re-alinement concerning oil whip. In this case, it needs many costs for maintenance and long shutdown times. In this study, we study and observe the oil whip of the 300MW steam turbine in many years and we conduct the field test for another steam turbine for reducing vibration from oil whip. The results of this study are that a oil whip takes place with a particular rotating speed or a particular turbine output and the oil temperature change is a very effective method for on-line oil whip treatment.

• Fisheries and Aquatic Sciences
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• 제24권6호
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• pp.207-218
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• 2021

This study evaluated the risk of foodborne illness from highly pathogenic Vibrio spp. (Vibrio vulnificus and V. cholerae) by raw whip-arm octopus (Octopus minor) consumption. In total 180 samples of raw whip-arm octopus were collected from markets and examined for the prevalence of V. vulnificus and V. cholerae. Predictive models describing the kinetic behavior of Vibrio spp. in raw whip-arm octopus were developed, and the data on amounts and frequency of raw whip-arm octopus consumption were collected. Using the collected data, a risk assessment simulation was conducted to estimate the probability of foodborne illness raw whip-arm octopus consumption using @RISK. Initial contamination levels of Vibrio spp. in raw whip-arm octopus were -3.9 Log colony-forming unit/g, as estimated by beta distribution fitting. The developed predictive models were appropriate to describe Vibrio spp. in raw whip-arm octopus during distribution and storage with R² values of 0.946-0.964. The consumption frequency and daily consumption amounts of raw whip-arm octopus per person were 0.47% and 57.65 g, respectively. The probability of foodborne illness from raw whip-arm octopus consumption was estimated to be 8.71 × 10^-15 for V. vulnificus and 7.08 × 10^-13 for V. cholerae. These results suggest that the risk of Vibrio spp. infection from raw whip-arm octopus consumption is low in South Korea.

• Nuclear Engineering and Technology
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• 제25권3호
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• pp.353-360
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• 1993

원자력 발전소에서는 고에너지배관이 파단되는 가상 배관 휩 현상으로부터 구조물을 보호하기 위하여 많은 종류의 배관 휩 구속장치(Pipe Whip Restraint, PWR)가 설치되어 있다. 이 배관 휩 구속장치를 보다 합당하게 설계하거나 배관 휩 구속장치의 설계타당성을 평가하기 위하여 배관 휩 현상을 자세히 관찰하는 것이 필요하다. 이와 같은 이유로 배관 휩 현상을 해석하는 방법 개발자 개발된 방법의 타당성을 입증하기 위한 다양한 연구 프로그램이 여러나라에서 수행되어 왔다. 본 연구에서는 배관 휩 구속장치에 가해지는 충격하중을 계산하기 위해 범용 유한요소 전산 프로그램인 ANSYS내의 여러 형태의 유한요소들을 이용하여 가상 배관 휩 현상을 모의했으며 계산 결과는 U자형 배관 휩 구속장치를 갖는 배관계통의 배관 휩 모의시험으로부터 구해진 대상 실험 결과와 비교, 검토되었다. 배관 휩 구속장치와 배관 사이의 갭요소나 스프링요소를 갖는 계산모델의 일부는 해당 실험결과와 비교해 볼 때 배관 휩 구속장치에 걸리는 인장력을 사고기간 동안에 잘 모의함을 보여서 배관 휩 구속장치의 설계타당성을 평가하는데 유용 할 것으로 판단된다.

• 한국식생활문화학회지
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• 제18권1호
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• pp.9-16
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• 2003

The purpose of this study was to develop the standardized recipe and to analyze the nutrients of stir-fried whip-arm octopus as one of the kind of traditional local foods in Busan. The standardized recipe was developed by using cookbooks, home recipes, and the recipes by commercial food restaurants. The nutrient was analyzed by using an AOAC method. Sensory evaluations were made on nine sensory attributes by a 12-member panel. As the results, the whip-arm octopus was recorded as a food source for health, rejuvenation in Jasanobo. Since early 1900, the stir-fried method has been used for cooking with the ship-arm octopus. The main ingredients were whip-arm octopus, onion, large green onion as the local stir-fried whip-arm octopus in Busan. The ingredients of soup were shrimp, little neck clam, and water. Seasoning sauce was mixed with red pepper powder, soy sauce, sesame oil, chopped garlic, chopped onion, and sugar. The seasoning sauce was fermented for three days. The results of sensory scores were salty seasoning 3.66/5.00, taste 3.75/5.00, thickness 3.84/5.00, and smell 4.09. Nutrient retention per 100g of the stir-fried whip-arm octopus was 67.54kcal, protein 6.43g, fat 1.66g, Ca 28.06mg, Fe 2.56mg, cholesterol 68mg, and taurin 51mg. Fatty acid consists of various unsaturated fatty acids such as linoleic acid(46.24%) and oleic acid(33.67%).

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.539-543
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• 2001

Almost all rotating machinery has bearings. Bearing is one of the most important part of rotating machinery. Vibration of rotating machinery depend on its bearing conditions. Bearing conditions are followings ; oil gap, bearing type, bearing temperature, bearing oil condition. Especially, bearing oil condition influences on rotating machinery vibration directly. In this paper we have discussed the abnormal vibration of turbine due to oil condition. oil whip problem was occured in the certain power plant. and we had sloved this problem through the control of operating values and alignment.

• 응용통계연구
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• 제29권7호
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• pp.1283-1294
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• 2016

한국 프로야구팀들의 실점을 설명하기 위한 수비지표를 연구하였다. 출루율과 장타율을 결합한 OPS가 팀들의 득점력을 매우 잘 설명한다는 사실을 동기로 하여 본 논문에서는 팀들의 실점을 설명하기 위한 수비지표를 연구하였다. 여러 가지의 수비지표 중 팀의 실점과 상관관계가 높은 것들을 결합하여 만든 몇 가지의 결합 지표들을 고려하였다. 프로야구 원년인 1982년부터 2015년까지의 정규리그 전 경기 자료를 분석한 결과 수정WHIP와 이닝당피홈런의 가중평균으로 정의되는 가중수정WPH2가 실점을 가장 잘 설명해줬다. 구체적으로 수정WHIP에 34%, 이닝당피홈런에 66%의 가중값을 두는 가중수정WPH2가 팀의 경기당 평균실점과 0.95362의 상관계수를 갖는 최적의 지표인 것으로 나타났다. 이 결과는 Kim과 Kim (2015a)에서 얻어진 지표에 의한 결과보다 좀 더 향상된 결과이다. 시대별 분석에서도 크게 다르지 않은 결과를 얻었다. 또한 얻어진 지표의 값이 좋은 투수 10명씩의 명단을 최근 3년간에 대해 연도별로 작성해보았다.

• 한국통신학회논문지
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• 제28권1A호
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• pp.41-46
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• 2003

직선형의 주 휩에 일정한 각도로 연결된 보조 휩을 갖는 선박용 안테나에 대해 보조 휩의 영향에 따른 안테나의 특성 변화를 조사하고, 이를 바탕으로 적절한 보조 휩을 갖는 중 단파대 선박용 휩 안테나를 설계하고자 한다. 먼저 완전 도체 평판 위에서 보조 휩의 개수, 위치, 길이 및 각도 등의 변화에 따른 안테나의 이득, 반사손실 및 복사패턴을 조사하여 보조 휩의 영향을 분석하였다. 이것을 바탕으로 안테나 구조를 결정하고, 이것을 한국해양대학교의 실습선에 설치하여, 바다 위에서 선박과 함께 안테나를 시뮬레이션을 하여 안테나의 특성을 계산하고, 입력 임피던스를 측정하여 시뮬레이션 값과 유사한 결과를 얻었다.

• 한국압력기기공학회 논문집
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• 제13권1호
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• pp.54-60
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• 2017

When a sudden rupture occurs in high energy lines, ejection of inner fluid with high temperature and pressure causes blast wave as well as thrust forces on the ruptured pipe itself. The present study is to examine pipe whip behaviors and blast wave phenomena under postulated pipe break conditions. In this context, typical numerical models were generated by taking a MSL (Main Steam Line) piping, a steam generator and containment building. Subsequently, numerical analyses were carried out by changing break locations; one is pipe whip analyses to assess displacements and stresses of the broken pipe due to the thrust force. The other is blast wave analyses to evaluate the broken pipe due to the blast wave by considering the pipe whip. As a result, the stress value of the steam generator increased by about 7~21% and von Mises stress of steam generator outlet nozzle exceeded the yield strength of the material. In the displacement results, rapid movement of pipe occurred at 0.1 sec due to the blast wave, and the maximum displacement increased by about 2~9%.