• Journal of Ship and Ocean Technology
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• v.8 no.4
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• pp.17-25
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• 2004

Hull girder stress monitoring system for container ship uses four long-base-strain-gages at mid-ship to monitor the resultant stresses and the applied moment components of horizontal, vertical and torsional moments. The bending moments are estimated by using the conventional strain-moment relations, however, the torsional moment related to the warping strain requires the assumption of the shape of torsional moments over the hull girder. Though this shape could be a sine function with an adequate period, it largely depends upon certain empirical formulas. This paper introduces additional four long-base-strain-gages at mid-ship to derive the longitudinal slope of the warping strain because this slope is directly related to the torsional moment by Bi-moment concept. An open-channel-type cantilever beam has been selected as a simplified model for container ship and the result has proved that the suggested concepts can estimate the torsional component accurately. Finally this method can become reliable technique to derive all external moments in hull girder stress monitoring system for container ships.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.1
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• pp.137-149
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• 2018

In this paper, under the assumption of the symmetry point spread function, antireflective boundary conditions(AR-BCs) are considered in connection with the fast truncated Lagrange(FTL) method. The FTL method is proposed as an image restoration method for large-scale ill-conditioned BTTB(block Toeplitz with Toeplitz block) and BTHHTB(block Toeplitz-plus-Hankel matrix with Toeplitz-plus-Hankel blocks) linear systems([13, 17]). The implementation and efficiency of the FTL method in the AR-BCs are further illustrated. Especially, by employing the AR-BCs, both the continuity of the image and the continuity of its normal derivative are preserved at the boundary. A reconstructed image with less artifacts at the boundary is obtained as a result.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.23 no.5
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• pp.471-477
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• 2014

The purpose of this study was to predict the load effect on a damper installed at a nuclear power plant building after a tsunami using a volume of fluid (VOF) numerical analysis method. The wave height was determined by a sine wave function and the tsunami condition was estimated by the wave length. Also, using computational fluid dynamics (CFD), the maximum damper load was set as a boundary condition for the structural analysis that verified how stress and deformation affect the damper. As a result, such simulations estimated the highest stress distribution for a wave length of 350 m with a maximum stress present at the cross point of stiffness installed at the rear end of the damper. The total deformation was approximately 32 mm at the center of damper.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.217-221
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• 2016

In this paper, a springboard for diving is analysed to find out how much force a diver should apply to reach specific height when the diver jumps. The springboard is presumed to Co-rotational plane cantilever beam(CR-beam), so EDISON program related to Co-rotational framework is used. The force of the person is supposed to sine function and the demanded height is fixed. Same velocity makes same height regardless of diver's weight. So, the velocity of springboard when the feet of a diver are separated from the springboard is a main factor of the analysis. The result shows that there is no association between deformation and weight and also between velocity and weight. That is, the required force to reach a optimal height is fixed whatever the diver's weight is.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.408-410
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• 1994

This Paper Presents a learning strategy for neural networks based on genetic algorithms and evolution strategies. Genetic algorithms and evolution strategies are used to train weights of feedforward neural network to solve problems faster than neural network, especially backpropagation. Simulations are performed exclusive-OR problem, full-adder problem, sine function generator to demonstrate the effectiveness of neural-GA-ES.

• Korean Institute of Interior Design Journal
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• v.15 no.1 s.54
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• pp.71-78
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• 2006

This study aims to understand the meaning of 'wall' and spatial image transformation by the wall. To find the meaning of wall, some classical works and modern works - Le Corbusier's Domino system and Schroder House-are analyzed into functional aspect of wall, in result we know that wall has of evolved throughout history to become an Increasingly active component of our built environment. Whereas the wall permits variations in the human and natural environment, the wall could be changed a lot of different shapes. The results of this study are as follows; (1) Applying new attempt to the wall makes interactivity in spatial elements. (2) Through rotation of the wall, we find the periodicity of wall length with sine curve. (3) Wall made by points and linear elements can change the spatial image, because of there geometrical characteristics.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1316-1318
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• 2003

The Bernstein polynomial is one of the classic algorithms of panoramic images mosaic for shading into process applying in Virtual Reality modeling. Nevertheless, it is proven that the algorithm has its own limitation and weakness in applications. This paper was given the improved algorithm using Sinusoidal function for image mosaic. In order to put the new algorithm into image processing software as a flexible and general tool, it was further developed an extension for graduation image fusion and multi-images mosaic.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.98-100
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• 2005

DSPs used at motor control are usually fixed point processor. They need scaling because they cannot excute floating point calculation. Scaling for floating point calculation makes the DSP's speed down, complex coding and etc. Therefore the IQ math is adopted. IQ math makes the fixed point processor possible to calculate the floating point math. In addition, IQ math can reduce memory usage and be more faster than that without IQ math. It seems that IQ math is appropriate in motor position control. In comparison of the position calculation between the IQ math, math function and the sine table, the method using IQ math is superior than other methods.

• Journal of the Korea Concrete Institute
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• v.16 no.5 s.83
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• pp.581-589
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• 2004

This paper compares the fatigue behaviors of concretes subjected to flexural and split-tensional loadings, and proposes the fatigue reliability models based on experimental results and reliability analysis. The fatigue tests were performed for the specimens of $150 mm{\times}75 mm$ split tensional cylinders and $150 mm{\times}150 mm{\times}550 mm$ flexural beams under constant loadings at three levels (70, 80 and $90\%$) with 0.1 stress ratio, 20 Hz loading speed and sine wave. The reliability analysis on fatigue data was based on Weibull distribution of two-parameters. From fatigue test results, two criteria were proposed to reject the experimental fatigue data because of statistical variation of concrete fatigue data. Two parameters ($\alpha$and u) of Weibull distribution were obtained using graphical method, moment method and maximum likelihood method. The probability density function(P.D.F) and cumulative distribution function(C.D.F) of the Weibull distribution for fatigue life of pavement concrete were derived for various stress levels using parameters, $\alpha$ and u. The goodness-of-fit test by Kolmogorov-Smirnov test was acceptable at $5\%$ level of significance. Based on reliability analysis, a fatigue model for pavement concrete was proposed and compared from existing models.

• School Mathematics
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• v.11 no.1
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• pp.111-129
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• 2009

This paper is about didactical transposition, which is to transpose academic knowledge into practical knowledge intended to teach. The research questions are addressed as follows. 1. Are the 13 mathematics textbooks of the 10-Na level indisputable regarding with the didactical transposition, in terms that the order of arrangement and the way of explaining the knowledge of trigonometric functions being analyzed and that its logical construction and students' understandings are considered? 2. Can some transpositions for easier use of didactical manipulative, for more practical and for more principle based be proposed? To answer these questions, this research examined previous studies of mathematics education, specifically the organization of the textbook and the trigonometric functions, and also compared orders of arranging and ways of explaining trigonometric functions from the perspective of didactical transposition of 13 versions of the 10-Na level reorganized under the 7th curriculum. The paper investigated what lacks in the present textbook and sought a teaching guideline of trigonometric functions(especially about sector and graph, period, characters of trigonometric function, and sine rule).