• Journal of the Korean Institute of Telematics and Electronics
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• v.11 no.6
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• pp.33-37
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• 1974

In this paper, the radiation characteristics for the array of a circular loop antenna is studied in moving media. The medium is assumed to be homogeneous, isotropic, and to move with a constant velocity much less than the speed of light. The integral equation for the current distribution is derived and the current functions is found by means of courier Series as a solution of the integral equation. The electric field is derived from the current on circular loop antenna and the Dyadic Green's Function in moving media. The numerical calculation of the electric field concerning to the two element antenna array,, in which one element is parasitic, is carried out. The field patterns are plotted from the computed values. As a result, the field patterns in moving media, compared with the patterns in stationary media, are found to decrease in the direction of media velocity and increase in the opposite direction, and the maximum directivity is shifted.

• Journal of the Korea Convergence Society
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• v.8 no.8
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• pp.325-332
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• 2017

This study was performed to investigate the effects of receiver's moving speed and pass types on anticipation timing response. Ten subjects were required to make a total of 24 passes in coincidence with an experimentally manipulated moving light signal in randomly three different conditions by performing chest and bound pass. Results of analyses revealed AE, CE, and VE increased as moving velocity became constant-acceleration condition. In addition, chest pass was more accuracy and consistency than bound pass on AE and CE. These findings indicated that moving velocity and pass type served as the major determination of coincident timing response on passing in basketball.

• Journal of the Korean Institute of Telematics and Electronics
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• v.7 no.3
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• pp.12-18
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• 1970

In this paper, the radiation characteristics of a Circular Loop Antenna is studied in a moving homogeneous, isotropic and linear media with a constant velocity much less than the speed of light. In Stuffing the radiation characteristics, Srst vector potential on the loop antenna is derived in the moving media by appling Maxwell-Minkowaski's theory. Next, using the derived relations, the electric and magnetic Seld is calculated for the spec-i Sed wave length ana velocity of the media. The Seld patterns in the moving media are compared with those of stationary media. We find that the intensity of the field is reduced in the direction of the media velocity and increased in the opposite direction only for the component parallel with the plane of the antenna. The deviation from the stationary media is proportional to the velocity of the media and the frequency of source current.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.224-227
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• 1998

Linear motors are increasingly employed as direct actuators replacing the more conventional systems composed by a rotating motor and a mechanical device. Linear DC motor is useful in a high speed and high accuracy positioning system with a feedback controller. Because of these advantages, linear DC motors have already been used as motors of pen recorders and magnetic disk storage devices, these are moving coil type linear DC motors as these movers are light. Moving magnet type linear DC motor has advantages at long stroke motors because its mover's feeding wires for driving is not necessary. This paper is concerned with the analysis of linear DC motor that is moving magnet type with unipolar. In order to analyze the dynamic behaviour a mathematical model based on a simplified field analysis developed. A two dimensional finite element field solution is employed in order to illustrate the effect of yoke saturation and motor performance. It is deduced the relation between the limit value of the thrust of the linear DC motor and the dimension of the yokes.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.408-413
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• 2005

This paper presents a technique which extracts a moving object from omni-directional images and estimates a real coordinates of the moving object using 3D parabolic coordinate transformation. To process real-time, a moving object was extracted by proposed Hue histogram Matching Algorithms. We demonstrate our proposed technique could extract a moving object strongly without effects of light changing and estimate approximation values of real coordinates with theoretical and experimental arguments.

• Agricultural and Biosystems Engineering
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• v.7 no.1
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• pp.8-12
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• 2006

This study was conducted to develop a real-time internal quality evaluation technique for Korean red ginseng using NIR spectroscopy while they were moving to be graded. Internal qualities of Korean red ginseng were defined by color, amount of white core and cavity in the red ginseng. To evaluate the internal quality, PLS (Partial Least Square) model was developed. Spectrum saturation can be occurred when most red ginseng has a sound internal quality expressed by higher light transmittance ratio, but that could not found in the ginseng of internal white core under the same light situation. And, if spectrum saturation is obtained, it is hard to identify the exact information of internal quality. In order to evaluate of the internal quality regardless of having internal normal core or white core, an integral time controlled method was used to obtain traditional spectrum. This procedure was applied in real-time process when red ginseng was moving to be graded in the line. Among the 450 samples including 223 internal normal ginsengs and 227 internal white core ginsengs, 315 ginsengs (70%) were used to develop a calibration model and 135 ginsengs were spent to validate the model. The result of quality evaluation by the model was very good showing SEP and bias were 0.3573 and 0.0310, respectively, and the accuracy was 95.6%.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.7
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• pp.1-7
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• 2013

LED lamps are appropriate to the light source for use in broadcasting lighting. When the lighting frequency of LED lamp is different from the shutter frequency of camera, however, the flicker appears on the moving image which is taken by the camera under the dimmed light of LED lamp with conventional dimming methods. In this study, a new dimming method for the LED lamps used as the broadcasting lighting is proposed to minimize the flicker. A lighting period in the proposed dimming method is divided into the several sub-periods which have weight of the bits. Also, the proposed dimming method has characteristics that are optimizing the turn-on timings of two LED lamps to reduce the turn-off periods of the lamps and not to overlap the turn-on periods of the lamps. In the experiments, the incidence of the flicker is taken by the camera under several lighting conditions of the conventional dimming methods and the proposed dimming method. In addition, the brightness values of the frames are obtained in the moving image, and incidence of the flicker is evaluated and compared with conventional methods. From the results, the incidence of the flicker in the proposed method is more improved than the conventional methods.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.86-89
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• 2005

A computational work has been performed to investigate the aerodynamics of a projectile which is launched from the two-stage light gas gun. A moving coordinate method for a multi-domain technique is employed to simulate unsteady projectile flows with a moving boundary. The effect of a virtual mass is added to the axisymmetric unsteady Euler equation system. The computed results reasonably capture the major flow characteristics which we generated in launching the projectile supersonically, such as the interaction between the shock wave and the blast wave, the interaction between the vortical flow and the barrel shock, and the steady under-expanded jet. The present computational results properly predict the velocity, acceleration, and drag histories of the projectile.

• Korean Journal of Optics and Photonics
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• v.11 no.4
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• pp.250-254
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• 2000

We have constructed laser Doppler velocimetry system using self-mixing effect with a semiconductor laser. This technology is based on the frequency mixing phenomena which occurs when light scattered back from the moving object into the laser cavity interferes with light inside the laser. We have compared the value of Doppler shifted frequency with the velocity variation of the wheel. Frequency dependence on the angle between the moving direction of rotating aluminum wheel and the incident beam also have been proved. As an illustration of the performance of the velocimeter, velocity measurements of a rotating disk are described. Doppler signal shows a good linear relationship with velocity of rotating disk.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1574-1585
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• 2007

In the more and more continues traffic difficulty which comes to be serious it is for solve, in order to like this used plan for new town light train automatic fare collection system, the city development which is balance and the passenger whom it uses, in consequence of the fact that recently believer instruction, the automatic fare collection system the reverse which is convenient is used in the scripture season which is embossed with means it introduces it operates and a manpower with the scientific service control which leads the electric computer anger of passenger service improvement and accounting and statistical business it reduces, the use is convenient and the possibility facility of operating efficiently in rational plan in order to be, description below for the service automation equipment where the efficiency improves it is. Service automation equipment uses a scripture season to be the first boundary gate of the passenger, there must be a place where it uses a service automation facility and in order to be convenient, it considers the moving area and a wait of the reverse station passenger moving area and the space where, must secure the automatic fare collection system which it follows in automation of facility and the service operation of the reverse station which is ticket sale, the collection of tickets back the passenger is convenient and in order it will be able to use, must do and must consider, must arrange the efficient characteristic of the maintenance civil official services.