• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.2
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• pp.51-60
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• 2012

An improved method for detecting fault distance in overhead transmission lines is described in this paper. Based on single-ended measurement, propagation theory of traveling waves together with the wavelet transform technique is used. In estimating fault location, a simple, but fundamental method using the time difference between the two consecutive peaks of transient signals is considered; however, a new method to enhance measurement sensitivity and its accuracy is sought. The algorithm is developed based on the lattice diagram for traveling waves. Representing both the ground mode and alpha mode of traveling waves, in a lattice diagram, several relationships to enhance recognition rate or estimation accuracy for fault location can be found. For various cases with fault types, fault locations, and fault inception angles, fault resistances are examined using the proposed algorithm on a typical transmission line configuration. As a result, it is shown that the proposed system can be used effectively to detect fault distance.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.29B no.2
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• pp.40-49
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• 1992

In this paper,a new approach-using the linear movement of the lens location in a camera and focal distance in each location for the measurement of the depth of the 3-D object from several 2-D images-is proposed. The sharply focused edges are extracted from the images obtained by moving the lens of the camera, that is, the distance between the lens and the image plane, in the range allowed by the camera lens system. Then the depthin formation of the edges are obtained by the lens location. In our method, the accurate and complicated control system of the camera and a special algorithm for tracing the accurate focus point are not necessary, and the method has some advantage that the depth of all objects in a scene are measured by only the linear movement of the lens location of the camera. The accuracy of the extracted depth information is approximately 5% of object distances between 1 and 2m. We can see the possibility of application of the method in the depth measurement of the 3-D objects.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.10
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• pp.1774-1779
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• 2016

This paper proposes a portable cable fault detection system with automatic fault distinction and distance measurement using time-frequency correlation and reference signal elimination method and automatic fault classification algorithm in order to have more accurate fault determination and location detection than conventional time domain refelectometry (TDR) system despite increased signal attenuation due to the long distance to cable fault location. The performance of the developed system method was validated via an experiment in the test field constructed for the standardized performance test of power cable fault location equipments. The performance evaluation showed that accuracy of the developed system is less than 1.34%. Also, an error of automatic fault type and location by detection of phase and peak value through elimination of the reference signal and normalization of correlation coefficient and automatic fault classification algorithm not occurred.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.4
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• pp.424-429
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• 2014

In this paper, an image-based luminance measurement system(LMS) is proposed to measure the luminance of outdoor signboards. We design the LMS that can improve disadvantages of efficiency of the point-luminance meter and portability of face-luminance meter using the image of DSLR camera and print out the luminance value by using the proposed luminance analysis algorithm in real time. Outdoor signboards have various size and shape, and are also installed on the various place. Luminance of the signboard is influenced by measurement location, angle, color, etc. Therefore, we measure the change of luminance value in accordance with measurement location for accurate luminance measurement and then consider the luminance value according to the measurement distance. We obtain a numerical relation between luminance value and measurement location. The proposed LMS is verified through comparative experiment with point-luminance meter.

• Industry Promotion Research
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• v.6 no.3
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• pp.19-24
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• 2021

There should be no problem in the measurement system for scientific quality management. In this paper, we want to correctly identify the factors that can affect the measurement results during the measurement process and identify what causes them when the measurement results cause problems in terms of location and variation. Variations in the measurement system are largely described in terms of location and dispersion. Location-related attributes are accuracy, stability, and linearity while dispersion-related attributes are reproducibility and repeatability. Analyzing the factors associated with dispersion is an R&R analysis, in which the size of repeatability and reproducibility is represented by a range of differences between multiple measurements and a range of differences between measurements, and 99% of dispersion is determined. Experimental design can also be used for measurement system analysis. Proper analysis is performed only when the factors causing the fluctuation, the worker and the product, are correctly identified as random or fixed factors.

• Journal of Multimedia Information System
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• v.8 no.1
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• pp.11-16
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• 2021

This study developed a design to estimate the location of rescue demander using the sound system at disaster site, in the conditions of indoor positioning cannot be performed properly. It is a location tracing system through smart phone application. It generates sound wave information of rescuer at the rescue site, and it can be used as assistant means for indoor location tracing at the disaster site using sound wave receiving measurement technology.

• Journal of Acupuncture Research
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• v.23 no.6
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• pp.77-83
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• 2006

Objectives : The purpose of this study was to investigate the location of LI20 and ST3 by facial measurement according to Sasang Costitution, Sex and Age. Methods : To collect the photograph of face, we used the face measurement apparatus, and then analysed whether ST3 was located out of the nasolabial sulcus or not. Results : ST3 was located at the lateral to the nasolabial sulcus in 94.9%; 92.1% of Soyangin, 97.7% of Taeumin, 94.4% of Soeumin 92.3% of male, and 92.3% of female according to Sasang Constitution and sex. According to age distribution, the highest percentage(100%) was appeared at $16{\sim}20$ age, and the lowest(91.8%) was appeared at $70{\sim}74$ age. Conclusion : This study suggests that actual measurement would be nessesary with classical literature to determine the location of acupuncture point, and we need more study in other race.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.10
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• pp.653-658
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• 2016

A study on the measurement of critical heat flux using the transient inverse heat conduction method in spray cooling was performed. The inverse heat conduction method estimates the surface heat flux or temperature using a measured interior temperature history. The effects of the measuring time interval and location of temperature measurement on the measurement of critical heat flux were primarily investigated. The following results were obtained. The estimated critical heat flux decreased as the time interval of temperature measurement increased. Meanwhile, the effect of measurement location on critical heat flux was not significant. It was also found, from the experimental results, that the critical superheat increased as the measurement location of thermocouple neared the heat transfer surface.

• Korean Journal of Acupuncture
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• v.35 no.4
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• pp.203-209
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• 2018

Objectives : The GB18 belongs to one of the 92 controversial points in the development of WHO standard of acupuncture point location. The number of Chon measurement of GB18 is described differently in the A-B Classic of Acupuncture and Moxibustion (ChimGuGakEulKyung; AB Classic) and the Complete Compendium of Acupuncture and Moxibustion(ChimGuDaeSeong; Complete Compendium). The aim of the study is to review the point location of GB18 and compare the relation of the location of BL7. In addition, I would like to propose new locating method of GB18. Methods : In order to review I examined the expressions of the location of GB18 and the mapping location on the acupuncture chart in the landmark classic acupuncture literatures. Results : In the most literatures, the location of GB18 was described by the distance from the GB17. The distance was 1.5 chon with one exception of 1 chon. The intervals from GB15 to GB18 was 1 chon or 1.5 chon. Although the distance from the anterior hairline is the same as 4 chon, mapping points of GB18 and BL7 on the acupuncture chart were different. Conclusions : Consequently, in the AB Classic, meaning of the location is the actual distance of scalp surface. In the Complete Compendium, however, meaning of the location is the hypothetical distance in the imaginary scalp surface. Therefore, it is safe to find the GB18 on the same level with GV20 on the connecting line of bilateral auricular apexes. The relation of GB18 and BL7 should be reconsidered.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.352-355
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• 2009

The ground resistance has been used as a method of estimating the capability of counterpoise. When transient currents blow through a ground electrode, it is reasonable to evaluate the performance of ground electrode system as a ground impedance instead of ground resistance. However, the measurement method of ground impedance for counterpoise is not clearly presented. This paper describes the measurement method of ground impedance considering the earth mutual resistances and AC mutual coupling. When we measure the ground impedance, the error due to earth mutual resistances depends on the distance between the auxiliary electrodes and the electrode under test. The measurement accuracy of high frequency ground impedance is mainly influenced by the location of the current electrode and the potential electrode.