• 대한조선학회논문집
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• 제50권5호
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• pp.291-297
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• 2013

Generally, form factor is determined through ITTC method. Determining the form factor from ITTC method includes the assumption that the form factor of a full-scale ship is the same value as its model ship. In other words, the form factor is independent on Reynolds number. However, for the more appropriate prediction of the resistance performance of a full-scale ship, the form factor must be determined with the consideration of the variation attendant on Reynolds number. In this research, several Geosim ship models are adopted to investigate the scale effect, and correlation lines of form factor are improved to suggest the better extrapolation method for the prediction of the form factor of full-scale ship. The corrected form factors using the correlation lines are compared with those determined from the results of low-speed resistance tests. To consider the influence of hull form, the correlation lines are determined for the group of high-speed ships and the group of low-speed ships, respectively. The corrected form factors have shown good agreement among the prediction results from each Geosim ship model to the full-scale ship.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권1호
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• pp.195-211
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• 2015

Flat plate friction lines have been used in the process to estimate speed performance of full-scale ships in model tests. The results of the previous studies showed considerable differences in determining form factors depending on changes in plate friction lines and Reynolds numbers. These differences had a great influence on estimation of speed performance of full-scale ships. This study was conducted in two parts. In the first part, the scale effect of the form factor depending on change in the Reynolds number was studied based on CFD, in connection with three kinds of friction resistance curves: the ITTC-1957, the curve proposed by Grigson (1993; 1996), and the curve developed by Katsui et al. (2005). In the second part, change in the form factor by three kinds of friction resistance curves was investtigated based on model tests, and then the brake power and the revolution that were finally determined by expansion processes of full-scale ships. When three kinds of friction resistance curves were applied to each kind of ships, these were investigated: differences between resistance and self-propulsion components induced in the expansion processes of full-scale ships, correlation of effects between these components, and tendency of each kind of ships. Finally, what friction resistance curve was well consistent with results of test operation was examined per each kind of ships.

• 대한조선학회논문집
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• 제51권3호
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• pp.231-238
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• 2014

In this study, the self-propulsion tests are performed in INHA towing tank. And the effective wake characteristics of the KVLCC2 and the KCS models are compared by the experimental results. The form factor is independent of Reynolds number. To estimate the hydrodynamic performance of a full scale ship, the form factor is determined to consider attendant on Reynolds number. In this research, the power predictions are carried out considering the form factor difference of model and full scale ship. The results of this research could be used as one of the fundamental data to the powering performance prediction.

• 대한조선학회논문집
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• 제56권2호
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• pp.109-116
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• 2019

This paper carried out numerical analysis for estimating the propulsion performance of the model scale ONRT benchmark model of'Tokyo 2015 a workshop on CFD'. The method reflecting the scale effect of ITTC'78 method and form factor were used to compare the estimates of the effective wake ratio of full-scale. The numerical calculation was performed with Siemens's Star-CCM+, compared with IIHR model tests and the numerical analysis results of other research institutes, showing good agreement. In the case of an open stern and twin skeg ship, the validity of the ITTC'78 method can be confirmed by assuming that the effective wake ratio estimated from the numerical analysis results of model scale is similar to the effective wake ratio of full-scale.

• 대한조선학회논문집
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• 제48권3호
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• pp.222-232
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• 2011

This article examines the scale effect of the flow characteristics, resistance and propulsion performance on a 317k VLCC. The turbulent flows around a ship in both towing and self-propulsion conditions are analyzed by solving the Reynolds-averaged Navier-Stokes equation together with the application of Reynolds stress turbulence model. The computations are carried out in both model- and full-scale. A double-body model is applied for the treatment of free surface. An asymmetric body-force propeller is used. The speed performances including resistance and propulsion factors are obtained from two kinds of methods. One is to analyze the computational results in model scale through the revised ITTC' 78 method. The other is directly to analyze the computational results in full scale. Based on the computational predictions, scale effects of the resistance and the self-propulsion factors including form factor, thrust deduction fraction, effective wake fraction and various efficiencies are investigated. Scale effects of the streamline pattern, hull pressure and local flow characteristics including x-constant sections, propeller and center plane, and transom region are also investigated. This study presents a useful tool to hull-form and propeller designers, and towing-tank experimenters to take the scale effect into consideration.

• 디자인학연구
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• 제16권4호
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• pp.405-412
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• 2003

본 연구는 이용자 중심의 버스정류장 쉘터를 계획, 설계함에 있어서 필요한 시각적 선호요인을 파악하기 위하여 “주변 환경이 일정할 때 쉘터는 어떠한 요인에 의해 선호되어지는가？”에 대한 연구의문에서 출발하여 버스정류장 쉘터 형태에 영향을 미치는 선호요인을 구명하였다. 본 연구는 등간척도의 점수부가체계를 적용하여 이용자에 의한 쉘터 형태의 시각적 선호를 평가한 후 시각적 선호와 이에 영향을 미치는 선호요인들과의 관계를 다중회귀분석방법으로 검정하였다. 이상의 연구 결과를 통하여 버스정류장 쉘터 형태의 시각적 평가에 의한 요인분석 결과는 이용자 중심으로 한 버스정류장 쉘터 디자인에 큰 영향을 미칠 것이다. 그러므로 본 연구 결과는 버스정류장 쉘터의 계획 및 설치에 필요한 지식을 제공해 주고 이용자의 만족을 극대화할 수 있는 쉘터 디자인과 버스정류장 조성에 기여할 것이다. 또한 버스정류장 시설물 관리에 있어서 이용자 중심의 쉘터 관리를 전략적으로 마련하는데 유용한 지침을 제공할 것으로 판단된다. 특히 일상생활에서 대중교통 이용자의 시각적 평가에 의한 선호요인 분석은 버스정류장 계획에 요체가 될 것으로 판단된다.

• 한국의류학회지
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• 제18권5호
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• pp.646-660
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• 1994

The purpose of this study was to investigate the difference of the visual evaluation about Clothing form and the surface image of detail. This study consists of pre-experiment for selecting the method of expression among detail which shows difference of the image and main experiment for identifying the clothing image as clothing form and the suface image of detial. Main experiment is made of factorial design for three variables-clothing form (H-line, A-line, V-line, X-line), detail (frill, tape), direction (width, length). Questionaire consists of 24 semantic differential scale expressing clothing form and detail. The subjects were 100 female students majoring in clothing and textile.7he data were analyzed by Frequencey, Factor analysis, Anova, scheffe's test and MCA method. The major findings were; 1) The image of clothing form and the surface image of detail were composed of 5 factors; attractiveness, prettiness, attention, modern, young. 2) For the visual evaluation of clothing form as the surface image of detail, there were significant differences in prettiness and attention factors. For the pretty and attentive image, we should express by the image of frill. 3) For the visual evaluation of the image of detail as clothing forms variation, there were significant difference in prettiness by A-line and X-line. 4) For the effect of clothing form and the surface image of detail, main effect was significant in attractiveness, prettiness, attention, modern factor. For the pretty image of clothing, it will be expressed by the image of frill and A-line, X-line. For the attentive image of clothing, it will be expressed by the image of frill and V-line. For the modern image of clothing, it will be expressed by the image of tape and V-line.

• 재활치료과학
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• 제4권2호
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• pp.84-91
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• 2015

본 연구는 해외 많은 분야의 재활에서 적용되고 있는 peer mentor 프로그램을 국내에 연구적, 임상적으로 도입하여 뇌졸중 환자의 정신적, 신체적 회복을 돕는 방법을 소개하고자 하였다. 두 집단 실험 설계로 뇌졸중이 발생한지 3-6개월인 환자들을 대상으로 설계하였다. 동료멘토는 뇌졸중이 발생한지 2년이 지난 외래 환자로 서로 다른 회복수준을 보이는 환자들로 구성하고, 프로그램을 운영하기에 앞서 참가자들에게 심리적, 평가적, 정보적인 도움을 주는 방법과 프로그램 운영 방법에 대해 교육한다. 한국판 노인 우울 척도 단축형 (Geriatric Depression Scale Short Form-Korea Version; GDSSF-K)을 사용하여 프로그램 참가자들의 심리적 요인을 측정하고, 뇌졸중 영향척도(Stroke Impact Scale; SIS)를 통해 회복수준을, 노인 상지 기능평가도구(Upper Extremity Function Test for the Elderly; TEMPA)을 사용하여 신체적 요인을 측정한다. 본 연구를 토대로 연구를 진행하고자 하는 연구자는 본 연구에서 제안한 방법과 더불어 뇌졸중 환자의 회복에 더 효과적인 프로그램 적용 방법에 대한 모색이 필요할 것이다.

• 한국주거학회논문집
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• 제12권4호
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• pp.105-113
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• 2001

This research indicates to controversial point that store equipments were not applying correct development factor in the each apartment house by that change rate by scale and uniformity of form and inefficiency, effect of discount store is increasing in apartment house and progressed research. The result are as follows; First, interior main point of store of that influence greatly to change rate number of store be. Second, being lot area in jar in outside factor of store. Third, discount store separation appeared by leading person who influence greatly to change rate in middle who is contiguity market singleness residential quarter and contiguity existence of commercial district and nonexistence and discount store separation of only outside right near at hand. Construction of commerce equipment may have to consist in practical apartment house after examine various kinds factor such as store indoor, store outside and only outside while plan practical use of systematic and efficient commerce equipment focusing more in efficient utilization of commerce institution that consist after plan that is not planed commerce equipment focusing in development in plan of commerce equipment in apartment house hereafter accordingly.

• 교육시설 논문지
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• 제26권5호
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• pp.25-36
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• 2019

School gymnasium is a multi-purpose large space building for various events and physical education activities, and is a facility that requires an approach to the desirable structural design, besides mechanical problems of structure against loads. For the integrated structure design concerning the architectural features, the major considerations of gymnasium planning that are the internal and external shape of the gymnasium, the space scale with structure members, the structural efficiency by members weight reduction and openness of the gymnasium space will have to take into account in the structural planning. From this point of view, the several cases of the school gymnasium were investigated and the parametric analyses were performed to the models using the various structural system. The parameters were the composition elements of structure system that are profile of structure, rigidity of member, connection and anchorage and stability. At the result, It was presented that the profile of structure member was the most influential factor to structural efficiency and the effect of the form and space of gymnasium. Also the design informations of structure design having the various feature of form and space were presented for the initial gymnasium planning.