• The Transactions of the Korean Institute of Electrical Engineers C
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• v.51 no.6
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• pp.253-259
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• 2002

This paper deals with the effects of grounding conductors for metal oxide surge arresters. When surge arresters are improperly installed, the results can cause costly damage of electrical equipments. In particular, the route of surge arrester connection is very important because bends and links of leads increase the impedances to lightning surges and tend to nullify the effectiveness of a grounding conductor. Therefore, there is a need to know how effective installation of lightning surge arresters is made in order to control voltage and to absorb energy at high lightning currents. The effectiveness of a grounding conductor and 18 [㎸] metal oxide distribution line arresters was experimentally investigated under the lightning and oscillatory impulse voltages. Thus, the results are as follows; (1) The induced voltage of a grounding conductor is drastically not affected by length of a connecting line, but it is very sensitive to types of grounding conductor. (2) The coaxial cable having a low characteristic impedance is suitable as a grounding conductor. (3) It is also clear from these results that bonding the metal raceway enclosing the grounding conductor to the grounding electrode is very effective because of skin effect. (4) The induced voltages of grounding conductors for the oscillatory impulse voltages are approximately twice as large as those for the lightning impulse voltages.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.3
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• pp.629-635
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• 2017

In this paper, we proposed a nonlinear synthesis filter for noise reduction to reduce the effects of Gaussian noise and impulse noise. When the centralization of the local mask is judged to be Gaussian noise by the noise judgment, the weight value of the weight filter are applied differently according to the spatial weight filter and the pixel change by using the sample variance in the local mask. And if it is determined as the impulse noise, we proposed an algorithm that applies different weights of local histogram weight filter and standard median filter according to noise density of mask. In order to evaluate the performance of the proposed filter algorithm, we used PSNR(peak signal to noise ratio) and compared existing methods and proposed filter algorithm in the mixed noise environment with Gaussian noise, impulsive noise, and two noises mixed.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.2
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• pp.475-481
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• 2014

As the society develops to advanced digital information times, many studies are underway about digital video processing technology areas such as image restoration. There are typical methods to restore the image which have been damaged by the impulse noise like SM(standard median) filter and CWM(center weighted median) filter. These filters show excellent noise reduction capabilities in low noise density areas, but in high noise density areas, noise reduction capabilities are not sufficient. In this paper, in order to restore the degraded images in impulse(Salt & Pepper) noise environment, the image restoration filter algorithm was suggested which expands and subdivide the mask focusing on damaged pixels. And to demonstrate the superiority of the proposed algorithm used PSNR (peak signal to noise ratio) as the standard of judgement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.4
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• pp.394-400
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• 2019

Noise removal is one of the required step in processing digital video and there are many researches to develop algorithm that fits with its purpose and environment. However, present impulse noise removal methods are lacking in its function in terms of removing noise in edge and high frequency factors. Therefore, this research has Extended range of masks depending on density to determine noise so that high frequency factors can be preserved. The range of resolution is set based on median and standard deviation of inside resolution after removing impulse noise. afterwards, those resolution within the range are calculated by adding weight to have the final output value. The suggested algorithm has an enhanced function in removing noise in various areas with many edge and high frequency factors than present methods and their functions are compared through simulation.

• Journal of IKEEE
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• v.25 no.4
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• pp.721-727
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• 2021

This paper proposes a UWB (Ultar-wideband) impulse generator using the gated ring oscillator. The oscillator and PLL circuits which generate a several GHz LO signal for the conventional architecture are replaced with the gated ring oscillator. Therefore, the system complexity is decreased. The proposed architecture controls the duty of enable signal, which is used for the head switch of ring oscillator. The control of the duty enables to tun off the oscillator during the guard interval and stop wasting the power consumption. The pulse shaping method using the counter makes the small side lobe and preserves the bandwidth regardless of the change on the center frequency. Designed UWB impulse generator could change the center frequency from 6.0 GHz to 8.8 GHz with a digital bit control, while it preserves the bandwidth as about 1.5 GHz.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.6
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• pp.543-549
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• 2005

This paper deals with modeling and analysis fer the landing motion of a human-body model. First, the dynamic model of a floating human body is derived. The external impulse exerted on the ground as well as the internal impulse experienced at the joints of the human body model is analyzed. Second, a motion planning algorithm exploiting the kinematic redundancy is suggested to ensure stability in terms of ZMP stability condition during a series of landing phases. Four phases of landing motion are investigated. In simulation, the external and internal impulses experienced at the human joints and the ZMP history resulting from the motion planning are analyzed for two different configurations. h desired landing posture is suggested by comparison of the simulation results.

• Journal of Families and Better Life
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• v.24 no.5 s.83
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• pp.175-189
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• 2006

The purpose of this study was to develop a standardized scale to measure consumption self-regulation. A preliminary 38-item scale was developed through a literature review. One thousand-twelve consumers responded to an online survey using the preliminary scale. A series of tests, such as test-retest, item-to-total correlation, Cronbach's reliability coefficient and factor analysis, were conducted using the survey data and a final scale comprising 30 items was then constructed. The consumption self-regulation scale consisted of four factors: (1) impulse control, (2) gratification delay, (3)self-reliance, and (4) self-management.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.1
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• pp.117-120
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• 2008

This paper investigates the convergence condition of ADILC(iterative learning control with advanced output data) for nonminimum phase systems. ADILC has simple learning structure including both minimum phase and nonminimum phase systems. However, for nonminimum phase systems, the overall time horizon must be considered in input update law. This makes the dimension of convergence condition matrix large. In this paper, a new sufficient condition is proposed to satisfy the convergence condition. Also, it has been shown that this sufficient condition can be satisfied although it is not full impulse response.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.5
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• pp.125-130
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• 2016

A low-recoil direct gun is useful in reducing the fire impulse generated by using a traditional shell. To apply a control equation to an AMESim Model, we have formulated a control equation for a recoil mechanism from the free object diagram. By modeling this equation, we have been able to compare the recoil distance and recoil force of a low-recoil direct gun. Here, we can analyze the recoil characteristics between traditional direct guns and low-recoil direct guns with perforated muzzle brakes. It is possible to mount a low-recoil direct gun with a perforated muzzle brake on a lightweight tracked vehicle by reducing its fire impulse.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.225-227
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• 2006

This note investigates the convergence condition of ADILC (iterative learning control with advanced output data) for nonminimum phase systems. ADILC has simple learning structure including both minimum phase and nonminimum phase systems. However, for nonminimum phase systems, the overall time horizon must be considered in input update law. This makes the dimension of convergence condition matrix large. In this paper, a new sufficient condition is proposed to satisfy the convergence condition. Also, it has been shown that this sufficient condition can be satisfied although it is not full impulse response.