• Journal of the Society of Naval Architects of Korea
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• v.50 no.5
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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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• v.7 no.1
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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.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.3
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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.

• Journal of the Society of Naval Architects of Korea
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• v.56 no.2
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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.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.3
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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.

• Archives of design research
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• v.16 no.4
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• pp.405-412
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• 2003

This research investigated the preference factor which has an effect on the forms of bus stop shelter in order to grasp the visual preference factor, which is necessary for planning and designing of bus stop shelter centering around user, starting with the question of the research regarding that a shelter is preferred by what kind of factor when the environmental conditions are regular. This research examined the relation between visual preference and preference factor which has an effect on it with Multiple Regression Analysis after evaluating visual preference for shelter form by user as applying of scoring system of Interval Scale. The result of the factor analysis by visual evaluation for the form of bus stop shelter through the said research result will have an great effect on the design of bus stop shelter centering around its user. Therefore, this research result will give a knowledge which is necessary for the plan and the installation of bus stop shelter, and contributes to shelter design and bus stop promotion which can maximize the satisfaction of user. As well, concerning the management of bus stop facilities, it will give useful guidelines for planning strategically the shelter management centering around user. In particular, It is estimated that the preference factor analysis by visual evaluation of the mass transportation user in daily life will be the cardinal point for bus stop plan.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.5
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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.

• Therapeutic Science for Rehabilitation
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• v.4 no.2
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• pp.84-91
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• 2015

The purpose of this study was introduce peer mentoring which is well used in various rehabilitation areas in overseas country to Korea academically and clinically and help psychological and physical recovery for stroke survivor. It was two group experimental design study, this protocol is designed for stroke survivor, 3-6 months after the onset. Peermentors were consisted of outpatients who is stroke survivor in different recovery levels, at least 2 year after the onset. Peermentors received education about how to support and mentor participants of the program emotionally, appraisally, and informationally and how to run the program. Geriatric Depression Scale Short Form-Korea Version(GDSSF-K) is used to measure psychological factor, Stroke Impact Scale(SIS) is used to measure recovery level of patient, and for physical factor Upper Extremity Function Test for the Elderly(TEMPA) was used. A researcher who is interested in the peer mentor program needs to find more effective applying method based on be offered method in this study for helping recovery after stroke.

• Journal of the Korean housing association
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• v.12 no.4
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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.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.5
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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.