• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.26-31
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• 2002

The recent machine tools are requested so high-quality processing and productivity increasing. Therefore, it is so necessary to develop technology fur high-speed and high-precision. This thesis touches on the development of high speed and intellectual line center. At first, the line center is necessary that strong structure, compact structure and light weight design for high-speed processing and transfer. So, it is necessary that examination of new materials and structures for light-weight and control devices for precision processing. So. it is going to make mention of the process of 1st model production for the above-mentioned based on test model production and evaluation.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.12
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• pp.1492-1497
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• 1999

High impedance fault(HIF) is defined as fault the general overcurrent relay can not detect or interrupt. Especially when HIF occur in residential areas, energized high voltage conductor results in fire hazard, equipment damage or personal threat. This paper proposes the model of the high impedance fault in transmission line using the ZnO arrester and resistance to be implemented within EMTP. The performance of the proposed model is tested on a typical 154[kV] korean transmission line system under various fault conditions. Wavelet transform is efficient and useful for the detection of high impedance fault in power system, because it uses variable windows according to frequency. In this paper, HIF detection method using wavelet transform can distinguish HIF form similar fault like arcfurance load, capacitor bank switching and line switching.

• East Asian mathematical journal
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• v.26 no.2
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• pp.267-280
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• 2010

In this paper we study construction methods of $n^{th}$ line in triangle. Russian Mathematician Zetel suggested some construction methods of $n^{th}$ line in triangle 80 years ago. We find Zetel's papers, in detail explain the Zetel's construction methods, and suggest two elementary construction methods. Our results are received in the process of Research and Education program in science high school.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.41-44
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• 2003

We propose portable equipment that monitors current and voltage of high-potential power transmission lines. In the equipment, a current and voltage sensor are attached to an insulator that supports a power transmission line: A clamped to the power line and the detected current signal is transmitted to the ground station by a wireless optical link using transmission line is detected by a high resistance element, zinc oxide (ZnO). That acts as a potential divider between the power line and ground. We make an experimental device for 66kV power line and demonstrate that it can monitor currents proposed equipment is small-sized, light, and inexpensive in comparison with the conventional CT (current transformer) and PT (potential transformer) since it does not require high potential insulators and magnetic cores, further, the equipment is easily installed owing to its small size and its simple structure.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.4
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• pp.341-346
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• 2002

When a construction company builds a high structure. many piles should be driven into the ground by a hammer whose weight is 7,000 kg in order to make the ground under the structure safe and strong. So. it is essential to determine whether a pile is penetrated into the ground enough to support the weight of the structure since ground characteristics at different locations are different each other. This paper proposes a visual measurement system for pile rebound and penetration movement including vibration using a high-speed line-scan camera and a specially designed mark to recognize two-dimensional motion parameters of the mark using only a line-scan camera. A mark stacking white and black right-angled triangles is used for the measurement, and movement information for vertical distance, horizontal distance and rotational angle is determined simultaneously. Especially- by adopting a line-scan CCD camera whose line rate is 20 ㎑. the measurement performance of dynamic characteristics of the pile at impact instant is improved dramatically.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.213-219
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• 2012

In this paper, we suggested the method of signal integrity for noises and distortion signal generated between high speed information transmission modules by external effects. Suggested method for signal integrity of impedance matching to remove transmission line distortion, We divided the impedance matching between the transmitter and the receiver module with the single line and differential line methods after confirmed the improvement of signal distortions through ADS simulation. the experimental results indicated that it is possible to keep signal integrity without signal distortions by matching the optimal termination impedance which are considering the signal delay of transmission line for using the high-performance modules.

• The Research Journal of the Costume Culture
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• v.14 no.4
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• pp.609-624
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• 2006

The purpose of this study is to give the guideline to the pattern designing by supplying various images of the transformed shape of tailored collar with the location and angle of gorge line and laying measurement of the tailored collar while designing the tailored collar. The results of this study are as follows : Images of the sample at the case of 1cm of laying measurement looks 'urban', 'light', 'sharp', 'young', 'fashionable' and 'narrow' than that at the case of 7cm. When the laying measurement increases, the image of the sample looks more 'classical' and 'boorish'. The image of the sample 'light', 'sensuous' and 'young' at the case of sample of which laying measurements of the collar was 3cm. Second, at the case of sample whose laying measurements of the collar was 5cm, it was shown that the low location of gorge line made the image of the sample 'soft' and 'short'. On the other hand the image of the sample looked 'hard', 'keen' and 'long' by the high location of gorge line. Third, at the case of sample of which laying measurements of the collar was 7cm, low location of gorge line made the image of the sample look short. However, normal location of gorge line made the image of the sample looked 'fashionable'. The images of the samples of which laying measurements of the collar were 3cm, 5cm and 7cm, respectively, had changed with the angle of gorge line. First, the high angle of gorge line made the image of the sample 'rigid' and 'keen' at the case of sample of which laying measurements of the collar was 3cm. The high angle of gorge line made the image of the sample looked 'boorish' and 'singular'.

• Korean Journal of Animal Reproduction
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• v.22 no.2
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• pp.137-143
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• 1998

The effects of continuous GH(hGH) secretion on the female reproduction was studies in adults female transgenic rats expressing the hGH gene with a mouse whey acid protein (mWAP) promotor. Two line of transgenic female rats carrying the mWAP/hGH gene were established and used in the study. One was characterized by relatively high levels of serum hGH (high line), and the other had relatively low levels (low line). 1. High line female rats had recurring, Pseudopregancy-like estrous cycles accompanied by increased serum progesterone level for 2 weeks after ovulation, and they were fertile. 2. In the rats, luteinization occurred spontaneously without cervical stimulation, probably due to high levels of serum hGH, which has prolactin (PRL)-like activity in the rat. 3. Low line female rats had recurring, regular 4-days estrous PRL surge following cervical stimulation were not, detected and PRL secretion was not induced by a dopamine antagonist. 4. The ovarian tissue in this line had a much higher number of corpora lutea and grew much heavier than in normal littermates, suggesting impairment of PRL induced structural luteolized. Su, pp.ession of PRL secretion in the low line rats was, at least in part, due to a marked decrease in the number of lactotrophs in the pituitary. The present study shows that the serum hGH level plays a crucial role in regulating luteal function in female transgenic rats expressing the hGH gene.

• Journal of the Korean Society for Railway
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• v.12 no.3
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• pp.427-436
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• 2009

This paper introduced Railway Network Design Problem (RNDP) to provide priority decisions on high-speed railway investment scenarios defined by various network segments and train systems. The RNDP optimizes the objective functions of minimize total travel time. Results show that the priority of high-speed railway investment is found to be East-west, West-coast, and South-coast line respectively. An entirely new line built with 400km/h is found to be the best alternative to East-west line. Regarding West-coast and South-coast line, the combined alternative of upgrading Geolla and Kyeonjon line with 200km/h and building a new line with 400km/h and 350km/h for remains of each line is the best.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1802-1807
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• 2004

When a construction company builds a high structure, many piles should be driven into the ground by a hammer whose weight is 7,000 Kg in order to make the ground under the structure safe and strong. So, it is essential to determine whether a pile is penetrated into the ground enough to support the weight of the structure since ground characteristics at different locations are different each other. This paper proposes a visual measurement system for pile rebound and penetration movement including vibration using a high-speed line-scan camera and a specially designed mark to recognize two-dimensional motion parameters of the mark using only a line-scan camera. A mark stacking white and black right-angled triangles is used for the measurement, and movement information for vertical distance, horizontal distance and rotational angle is determined simultaneously