• 한국항해항만학회지
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• 제37권5호
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• pp.559-565
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• 2013

본 연구의 목적은 우리나라 항만의 예선 서비스 현황, 운영제도 및 구조적인 문제점이 무엇인지를 살펴보고 예선제도가 갖고 있는 문제점을 계층적으로 분석하여 개선사항의 우선순위를 도출하고자 한다. 우리나라의 예선 서비스 개선에 관한 주요 요인들 중에서 고객요인, 예선운영협의회 운영 행태, 예선법규, 서비스품질 등과 비교해서 예선운영제도(자유계약제, 순번제)가 가장 시급히 개선되어져야 하는 것으로 조사되었다. 예선업체들의 서비스 마인드 개선도 중요한 요인이며, 신규 예선업체의 시장진입을 용이하게 하는 예선진입제도의 개정 또한 중요한 요인으로 나타났다. 본 연구의 결과, 우리나라 예선제도 및 서비스 개선 요인들 중 가장 중요한 것은 예선업자들의 서비스 의식을 제고할 수 있는 예선운영제도의 변화인 것으로 나타났다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2311-2315
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• 2013

Objective: To investigate the expression level of TUG1 and one of its transcript variants (n377360) in osteosarcoma cells and assess the role of TUG1 in proliferation and apoptosis in the U2OS cell line. Methods: TUG1 and n377360 expression levels in patients with osteosarcomas and the U2OS human osteosarcoma cell line were evaluated using real-time quantitative PCR. U2OS cells were transected with TUG1 and n377360 siRNA or non-targeting siRNA. MTS was performed to assess the cell proliferation and flow cytometry was applied to analyze apoptosis. Results: We found significantly higher TUG1 and n377360 expression levels in osteosarcoma tissues compared with matched non-tumorous tissues. In line with this, suppression of TUG1 and n377360 expression by siRNA significantly impaired the cell proliferation potential of osteosarcoma cells. Furthermore, inhibition of TUG1 expression significantly promoted osteosarcoma cell apoptosis. Conclusions: The overexpression of TUG1 and n377360 in osteosarcoma specimens and the functional role of TUG1 and n377360 regarding cell proliferation and apoptosis in an osteosarcoma cell line provided evidence that the use of TUG1 or n377360 may be a viable but an as yet unexplored therapeutic strategy in tumors that over express these factors.

• Restorative Dentistry and Endodontics
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• 제42권4호
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• pp.273-281
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• 2017

Objectives: The aims of this study were to quantify tug-back by measuring the pulling force and investigate the correlation of clinical tug-back pulling force with in vitro gutta-percha (GP) cone adaptation score using micro-computed tomography (${\mu}CT$). Materials and Methods: Twenty-eight roots from human single-rooted teeth were divided into 2 groups. In the ProTaper Next (PTN) group, root canals were prepared with PTN, and in the ProFile (PF) group, root canals were prepared using PF (n = 14). The degree of tug-back was scored after selecting taper-matched GP cones. A novel method using a spring balance was designed to quantify the tug-back by measuring the pulling force. The correlation between tug-back scores, pulling force, and percentage of the gutta-percha occupied area (pGPOA) within apical 3 mm was investigated using ${\mu}CT$. The data were analyzed using Pearson's correlation analysis, one-way analysis of variance (ANOVA) and Tukey's test. Results: Specimens with a strong tug-back had a mean pulling force of 1.24 N (range, 0.15-1.70 N). This study showed a positive correlation between tug-back score, pulling force, and pGPOA. However, there was no significant difference in these factors between the PTN and PF groups. Regardless of the groups, pGPOA and pulling force were significantly higher in the specimens with a higher tug-back score (p < 0.05). Conclusions: The degree of subjective tug-back was a definitive determinant for master cone adaptation in the root canal. The use of the tug-back scoring system and pulling force allows the interpretation of subjective tug-back in a more objective and quantitative manner.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.3-13
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• 2004

The total tug capacity needed for berthing/de-berthing operations of a ship may vary depending on the ship type, size, loading conditions, and environmental circumstances. Traditionally, total tug capacity is determined based on the local guidelines of port authorities or on the rule of thumb. However, the social demands for the enhancement of ship safety at harbor and the economical demands for the cost-effectiveness of tug usage makes it necessary for port authorities to develop more reasonable and detailed guidelines on tug usage which takes various conditions into account. In this paper, the method to estimate the optimum tug capacity of VLCC is suggested by considering various ship conditions such as its size, loading conditions, and environmental circumstances such as wind, wave, tidal currents, and geographical characteristics of a terminal. This method is applied to a VLCC terminal located in Gwang-Yang Harbor of Korea and the results are compared with the local guidelines of the harbor, which shows that there may be a room for the amendment of local guidelines on tug usage.

• 한국항해항만학회지
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• 제36권1호
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• pp.15-20
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• 2012

예선이 부선을 선미예인하고 있는 상황에서의 예부선 조종특성을 확인하기 위하여, 예선 단독 실선시운전과 예부선 통합 실선시운전 시험을 수행하였다. 속력시험, 가감속시험, 10도 선회시험, 20도 선회시험, 10도 지그재그시험, 20도 지그재그시험을 통하여 다양한 상황에서의 예선과 부선의 운항 특성을 확인하였다. 그 결과, 부선이 선미예인되는 경우, 예선의 전술선회직경은 예선 단독운항일 때보다 증가하며, 선수동요각 변화율이 낮음을 확인하였고, 침로 변경을 함에 있어 부선의 선수동요각 변화가 늦고, 오버슈트각이 큰 것을 확인하였다. 또한 선회나 침로 변경 시, 부선의 선회궤적이 예선의 선회궤적 안쪽에도 존재할 수 있음을 확인하였다. 따라서 부선을 선미예인하는 운항자는, 선회 및 침로변경 시 예부선의 선회궤적, 예부선의 선수동요각 변화시간 및 오버슈트각이 증가하는 것을 충분히 인지하고 운항해야 할 것으로 판단된다.

• 대한조선학회 특별논문집
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• 대한조선학회 2009년도 특별논문집
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• pp.65-70
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• 2009

In case that tug boat pushes side structures of other large vessels to maneuver, it is required that contacted side structures of the maneuvered vessels have enough structural safety against tug push loads. The objective of this study is to evaluate the structural effect of carling which is installed between side longitudinal stiffeners. A comparative study of side structures with carling and without carling is performed to evaluate the effect of carling member by both FE analysis. According to the result, it is found that the carlings play effective role in the strength of side plates and side longitudinal stiffeners against tug push loads.

• Physical Therapy Rehabilitation Science
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• 제6권4호
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• pp.176-181
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• 2017

Objective: The timed up and go (TUG) test is method used to determine the functional mobility of persons with stroke. Its reliability, validity, reaction rate, fall prediction, and psychological characteristics concerning ambulation ability have been validated. However, the relationship between TUG performance and community ambulation ability is unclear. The purpose of this study was to investigate whether the TUG performance time could indicate community ambulation levels (CAL) differentially in persons with chronic stroke. Design: Cross-sectional study. Methods: Eighty-seven stroke patients had participated in this study. Based on the self-reporting survey results on the difficulties experienced when walking outdoors, the subjects were divided into the independent community ambulation (ICA) group (n=35) and the dependent community ambulation group (n=52). Based on the area under the curve (AUC), the discrimination validity of the TUG performance time was calculated for classifying CAL. The Binomial Logistic Regression Model was utilized to produce the likelihood ratio of selected TUG cut-off values for the distinguishing of community ambulation ability. Results: The selected TUG cut-off values and the area under the curve were <14.87 seconds (AUC=0.871, 95% confidence interval=0.797-0.945), representing a mid-level accuracy. Concerning the likelihood ratio of the selected TUG cut-off value, it was found that the group with TUG performance times shorter than 14.87 seconds showed a 2.889 times higher probability of ICA than those with a TUG score of 14.87 seconds or longer (p<0.05). Conclusions: The TUG can be viewed as an assessment tool that is capable of classifying CAL.

• 한국전문물리치료학회지
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• 제20권4호
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• pp.40-46
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• 2013

The purpose of this study was to determine which spatiotemporal gait parameters obtained during hemiplegic walking could be a predictive factor for the Timed Up and Go test (TUG). Two hundreds nine subjects who had suffered a stroke were recruited for this study. They were participated in two assessments; the TUG test and gait analysis. The relationship between the TUG test and spatiotemporal parameters was analyzed using Pearson's correlation coefficients. In addition, to predict the spatiotemporal gait parameters that correlated most with the TUG scores, we used multiple linear regression analyses (stepwise method). The results show that the normalized velocity was strongly correlated with the TUG performance (r=-.72, p<.001). Additionally, single support percentage (SSP), double support percentage (DSP), step time difference (STD), and step length difference (SLD) significantly were correlated with the TUG test. Normalized velocity, STD, DSP of affected side, and SSP of non-affected side explained 53%, 8%, 3%, 2%, of variance in the TUG test respectively. In conclusion, an increase in gait velocity and a decrease in STD would be effective indicators of improvement on the functional mobility in the stroke rehabilitation.

• 한국항해항만학회지
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• 제32권9호
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• pp.711-716
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• 2008

Marine accidents related to the tug-barges are frequent recently, such as oil spill caused by collision between oil tankers and tug-barges. There are many causes of these accidents, but poor working condition of operators takes up a considerable part of most causes. That is, the danger of accidents caused by fatigue accumulation exists in tug-barges of less than 200 gross tonnage engaged on near-coastal voyages or short shipping, because of the long-distance navigational watch by only one master. This paper aims to deduce problems of human element part out of the plan of sqfe navigation, and to propose legal amendments for preventing marine accidents by tug-barges.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2008년도 춘계학술발표회
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• pp.43-47
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• 2008

예부선 운항 시 부두의 전안, 이안 및 좁은 수로를 항행할 경우 접할 수 있는 안벽근처의 항행과, 두 선박이 접근하여 평행항의 상을 반대 방향으로 항과 할 경우의 유체력 상호작용을 살펴보기 위하여, 본 연구에서는 예선의 부선 예항 시뮬레이션을 실시한 후 부선의 선수방향, 예선의 회두 모멘트와 횡방향의 힘과 같은 유체력 특성을 조사 및 분석하여 그에 따르는 안전한 예부선의 조선방안을 제시하였다.