• 전기의세계
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• v.25 no.5
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• pp.75-78
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• 1976

The most difficult problem encountered in impulse test of transformer is the determination of exact fauly for coil layer short. This paper is to establish one of improved standards in the above case by means of wave form analysis, based on the equivalent circuits and experimental investigation. During the fault occurs, the local oscillation in fault circuit is applicable where as the reflection wave is utilized to the main circuit. The result current wave form at neutral impeadance point is similar to the wave form by impulse test and has the singular wave form respectively.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1978.06a
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• pp.9.1-10
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• 1978

Recently the authors have observed various wave-forms by insertion of induction coil into the scala tympani as well as attached outer device in the outside of the body in damaged hair cells of the cats. In the cochlear nerve. action potential indicated different polarities induced by examination of the bundle of the cochlear nerve fibers. Impulse wave-form as a result of excitation of cohlear nerve fibers showed bipolar wave-form such as negative 1 and positive 1. Therefore action potential showed also bipolar wave-form as above mentioned. We can obtained suitable response with above mentioned outer and inner device as an exact oscillogram.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2001.11a
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• pp.163-166
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• 2001

In this paper, the superposition of ultrasonic signals which were generated by multi-source in a transformer was presented. For analysis of ultrasonic superposition, V$_{peak-peak}$ and pulse number of ultra-sonic signal were used. As a result, the wave form of ultrasonic superposition was classified into three types ; First type was the wave form whose V$_{peak-peak}$ was increased by the superposition of each signal's V$_{peak-peak}$. Second type was wave form whose V$_{peak-peak}$ was decreased by the superposition of each signal's V$_{peak-peak}$. And the other type was wave form whose peals were two or mere. And V$_{peak-peak}$ of superposed ultrasonic wave wads mostlv increased or decreased and pulse number of supe게osed u1trasonic wave was mostly increased.y increased.

• Fashion & Textile Research Journal
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• v.7 no.6
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• pp.641-649
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• 2005

This study is to make pH 9 reduction by adding NaOH to 1, 3, 5, 7, 9, 11% solution of thioglycollic acid, cysteine, cysteamin, to add it on helically winded natural hair and colored hair and leave them for 20, 40, 60 minutes, to add $NaBrO_3$ oxidant for 15 minutes and to compare and analyze the wave form. This study showed the results of permanent using thioglycollic acid, cysteine, cysteamin. In the permanent wave form according to the kind of reductant, concentration, and processing time, there were a little difference between thioglycollic acid and cysteine. But cysteamine not only showed apparent difference but also formed strong and elastic wave. The permanent wave is affected by the diagonosis of hair, the choice of permanent solution and the processing time. Therefore the scientific diagonosis of hair is to be considered first of all. By choosing the kind of solution, the concentration and the processing time according to the results of hair diagonosis and wave form, we can prevent the lengthening and damage of hair.

• Bulletin of the Society of Naval Architects of Korea
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• v.18 no.1
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• pp.9-18
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• 1981

The wave-pattern analysis has been one of important research tools in the towing tank, and applied for hull form design. The longitudinal-cut method of Newman and Sharma is adopted in KRIS deep towing tank. Instrumentations and data acquisition systems are developed for that. Local effects and truncation effects are estimated by using calculated wave patterns of simple source distributions. Wigley model of 2m is used to check the accuracy of the whole system. Cut positions and truncation points are changed to investigate characteristics of the wave-pattern analysis. Coefficients of wave-pattern resistance are low-estimated in comparison with those of Maruo and Ikehata. The general quality of the system is very good, but some more efforts to increase the accuracy are required. Two full-form models(one basic form, the other with bulbous bow) are tested to show high application-possibilities of the wave-pattern analysis for the hull form design.

• Journal of Korean Ophthalmic Optics Society
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• v.5 no.2
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• pp.5-9
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• 2000

The visual evoked potential was electrophysiological method for the identify of the EEG response on visual cortex. This test was objective test method on the eye function. This study was used the visual evoked potential for the objective color test. The subjects was a normal color function in Korean adults. The test condition was performed on the differens distance and illumination. According to convergence condition of color vision target. On the appearance of EEG wave of visual stimulation on visual cortex. The most EEG wave style was delta wave, and the next amount wave form was beta wave and theta wave, and the least EEG wave form was alpha wave. The histogram of amplitude of EEG wave form was almost non-Gaussian shape, and the phase diagram of amplitude was almost all linear shape. On the kinds of color vision target, the frequency of EEG wave style appeared a similar results.

• Bulletin of the Society of Naval Architects of Korea
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• v.17 no.1
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• pp.19-24
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• 1980

From the singularity distribution which obtained by minimum wave resistance condition, optimum hull form is obtained by stream line trancing method as Inui and Pien did. Thus obtained hull form has a extruded bottom along a keel line. Therefore the hull form must be modified to have flat bottom. This modification process is conducted by putting a fictitious bottom. It is found out that the wave resistance does not significantly alter at design speed even though the hull form has remarkably changed at the bottom. Therefore flattening the bottom by the effect of depth may be more rational for practical hull form design than ordinary manual hull-form modification.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.6
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• pp.527-534
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• 2018

The segment of the piston type wave board has been expressed as a submerged vertical line segment in the two dimensional wave flume. Either end of vertical line segment representing wave board could be located in fluid domain from free surface to the bottom of the flume. Naturally the segment could be extended from the bottom to the free surface of the flume. It is assumed that the piston motion of the wave board could be defined by the sinusoidal oscillation in horizontal direction. Simplified analytic solution of the submerged segment of wave board has been derived through the first order perturbation method in water of finite depth. The analytic solution has been utilized in expressing the wave generated by the piston type wave board installed on the upper or lower half of the flume. The wave form derived by the analytic solution have been compared with the wave profile obtained through the CFD calculation for the either of the above cases. It is appeared that the wave length and the wave height are coincided each other between analytic solution and CFD calculation. However the wave form obtained by CFD calculations are more closer to real wave form than those from analytic calculation. It is appeared that the linear solutions could be not only superposed by segment but also integrated by finite elements without limitation. Finally it is proven that the wave generated by the oscillation of flap type wave board could be derived by integrating the wave generated by the sinusoidal motion of the finite segment of the piston type wave board.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.5
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• pp.499-508
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• 2017

This paper uses optimization techniques to obtain bow hull form of a 66,000 DWT bulk carrier in calm water and in waves. Parametric modification functions of SAC and section shape of DLWL are used for hull form variation. Multi-objective functions are applied to minimize the wave-making resistance in calm water and added resistance in regular head wave of ${\lambda}/L=0.5$. WAVIS version 1.3 is used to obtain wave-making resistance. The modified Fujii and Takahashi's formula is applied to obtain the added resistance in short wave. The PSO algorithm is employed for the optimization technique. The resistance and motion characteristics in calm water and regular and irregular head waves of the three hull forms are compared. It has been shown that the optimal brings 13.2% reduction in the wave-making resistance and 13.8% reduction in the added resistance at ${\lambda}/L=0.5$; and the mean added resistance reduces by 9.5% at sea state 5.

• 한국기계연구소 소보
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• s.9
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• pp.169-181
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• 1982

This paper presents three methods for ship hull form improvement on the basis of wave pattern analysis. These methods are primarily based on the assumption that a linear relation exists between the small difference of hull sections and the difference of the wave amplitude functions. The improved hull form of ship is made by superposing a thin hull form on that of a parent model. The first method use the simplification of framelines and Michell's Theory to the formula of wave resistance for superposed thin ship. The second method use tent functions and Michell's Theory to that. And the third is experimental method.