• Journal of Advanced Marine Engineering and Technology
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• v.28 no.8
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• pp.1258-1269
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• 2004

The fluid dynamic characteristics of a circular arc type sea anchor were calculated by a discrete vortex method. The flow for the surface of the sea anchor was represented by arranging bound vortices at adequate intervals. The simulations were performed by assuming that the separations occur at edges. With time, the drag coefficient was almost constant but the lift coefficient oscillated in a cycle due to von Karman's vortex street. As the camber ratios increase, the drag coefficient and Strouhal number were almost constant but the oscillating amplitude of the lift coefficient increased largely.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.6
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• pp.76-81
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• 2006

In this paper, profile error measurement method of a turbine blade using 3D-scanner is developed. The method begins with scanning the upper and lower sides of the blade on which three small balls are attached, and constructs a solid measurement model by registering the two scanned surfaces. Airfoils are derived from the model at each interval by intersecting it with a plane, and arranged with design airfoils. The $2^2$ factorial design search method is engaged in arranging the two airfoils, from which the main blade parameters including the edge radius are computed. The developed measurement technique is applied to practical blade manufacturing and validates its effectiveness.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1303-1308
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• 2008

In this study, we researched how to estimate life-stress relationship and acceleration factor through performing accelerated life test and analyzing it. The purpose of this study is to predict life of pneumatic cylinder within short time which is widely used in automation manufacturing line. In design of accelerated life test, we selected operating pressure and load that have the most influence on main failure mode of pneumatic cylinder as accelerated factor. We used two-way factorial design for arranging of test condition to accelerated factor and accelerated level.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.3
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• pp.365-372
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• 2003

The Flow patterns around two cylinders in various arrangements were studied by a discrete vortex method. The flow for the surface of each cylinder was represented by arranging bound vortices at adequate intervals. The viscous diffusion of fluid was represented by the random walk method. The vortex distributions. streaklines. timelines and velocity vectors around two cylinders were calculated for centre-to-centre pitch ratios of P/D=1.5 and 2.5, attack ang1es of $a=0^{circ}, 30^{circ}, 60^{circ} and 90^{\circ}$. and Reynolds number of Re= 1200. The results of simulation correspond to the photographs by flow visualization and the flow intereference between two cylinders in various arrangements were clearly visualized by a numerical simulation.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2012.06a
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• pp.152-153
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• 2012

While engine room arranging pipe which is used from the vessel, It measured the internal flow of 90 degree elbow which is used from the main condenser. Fluid flow in elbow of 90 degree is measured by PIV and Dewetron system. The Reynolds number adopts 50000 and experimental study of flow field in the elbow.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.210-215
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• 2003

A fine hot-wire is used both as a heating element and a temperature sensor in transient hot-wire method. The traditional sensor system is unnecessarily big so that it takes large fluid volume to measure the thermal conductivity. To dramatically reduce this fluid volume, a new sensor fabrication and a data processing method are proposed in this article. Contrast to the conventional and most popular two wire sensor, the new sensor system is made up of divided multiple long and short wires. Through validation experiments, it is found that the measured thermal conductivities of the glycerin are exactly same each other between the conventional and proposed new method. Also some technical considerations in arranging the multiple wires are briefly discussed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.763-764
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• 2012

In this paper, we propose the method to derive effective GRM coefficients for each $2^n$ polarities using triangle cell. In this paper, cell is defined so as to obtain GRM coefficients efficiently. After arranging 2n given RM coefficients of first row of cell, sequence modulo sum is performed in parallel to low column by a fixed numerical formula. To prove the efficiency of proposed arithmetic method, it is compared with earlier method.

• Phonetics and Speech Sciences
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• v.8 no.2
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• pp.23-30
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• 2016

This paper describes some implementation schemes of CNN in view of mini-batch DNN training for efficient second order optimization. This uses same procedure updating parameters of DNN to train parameters of CNN by simply arranging an input image as a sequence of local patches, which is actually equivalent with mini-batch DNN training. Through this conversion, second order optimization providing higher performance can be simply conducted to train the parameters of CNN. In both results of image recognition on MNIST DB and syllable automatic speech recognition, our proposed scheme for CNN implementation shows better performance than one based on DNN.

• Proceedings of the KOSOMBE Conference
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• v.1989 no.05
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• pp.67-69
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• 1989

In this paper, principles of Rhcoencephalography(RBG) was described and RBG was designed and developed. Using the developed instrument, RBG waveforms of the left and right brain, RBG waveform changes by posture, were observed. It was found that RBG waveforms could be observed noninvasively. RBG can be easily applied for testing the effect of various drugs related to CBF(Cerebral blood flow) since it is quite sensitive to the relative changes of CBF. Various cerebral diseases can be diagnosed by analyzing the RBG waveforms. The area of restricted cerebral blood vessels can be located by arranging the appropriate electrode configuration.

• Journal of Sensor Science and Technology
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• v.11 no.4
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• pp.191-199
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• 2002

This paper presents the design concept, theoretical investigation, and fabrication of a six-degree of freedom (6-DOF) turbulent flow micro sensor utilizing the piezoresistive effect in silicon. Unlike other flow sensors, which typically measure just one component of wall shear stress, the proposed sensor can independently detect six components of force and moment on a test particle in a turbulent flow. By combining conventional and four-terminal piezoresistors in Si (111), and arranging them suitably on the sensing area, the total number of piezoresistors used in this sensing chip is only eighteen, much fewer than the forty eight piezoresistors of the prior art piezoresistive 6-DOF force sensor.