• 산업기술연구
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• 제30권A호
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• pp.83-88
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• 2010

Recently, the LED lighting is widely used to illumination purpose due to its high luminous efficiency and the long life time. However, the light power and lifetime is reduced by junction temperature increment of LED. So it is important to measure the junction temperature accurately. In this paper, we proposed a new design and implementation method of high power LED junction temperature measurement circuit. The proposed circuit has two current sources which are a driving current source and a measurement is verified by experiment, and the result shows that the proposed circuit is appropriate to practical use.

• 산업기술연구
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• 제27권B호
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• pp.9-14
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• 2007

In this paper, four types of igniters were modeled and their characteristics were researched. And then we analyzed and experimented the effect on the control IC operation in this system. Due to the high ignition voltage, the DC power line on control IC is contaminated with the impulsive noise voltage. So the control IC operation is stopped. Therefore we have found that contamination of DC power noise is reduced by shielding, grounding pattern, and filtering method. We showed that the experimental results are agreed with the theoritical value obtained by the four types of ignitor models.

• 대한소아치과학회지
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• 제25권1호
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• pp.144-151
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• 1998

Cleidocranial dysplasia (CCD), which is accepted as an autosomal disorder, is a generalized disorder of bone with severe dental abnormalities. Among the most characteristic anomalies seen are hypoplasia of clavicles or aplasia of clavicles, permanant non-ossification of cranial sutures & fontanels, delayed eruption of the permanant dentition & the presence of unerupted supernumerary teeth. CCD may first be noted by dentist because of many dental problems, so we should diagnose the disorder earlier & understand the development of dentition in CCD to ensure timely intervention with proper periodic dental X-ray.

• 반도체디스플레이기술학회지
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• 제8권1호
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• pp.19-25
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• 2009

Abstract JPEG2000 achieve quality scalability through the rate control method used in the encoding process, which embeds quality layers to the code-stream. This architecture might raise two drawbacks. First, when the coding process finishes, the number and bit-rates of quality layers are fixed, causing a lack of quality scalability to code-stream encoded with a single or few quality layers. Second, in Post compression rate distortion (PCRD) the bit streams after the truncation points discarded. Therefore, computational power for the discarded bit streams is wasted. For solving of problem, through bit rate control, there are many researches. Each proposed algorithms have specially target feature that is improved performance like reducing computational power. Research results have strength and weakness. For the mean time, research contents are reviewed and compared, so we proposed research direction in the future.

• Communications for Statistical Applications and Methods
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• 제13권2호
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• pp.297-307
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• 2006

Most methods for describing the relationship among random variables require specific probability distributions and some assumptions of random variables. The mutual information based on the entropy to measure the dependency among random variables does not need any specific assumptions. And the redundancy which is a analogous version of the mutual information was also proposed. In this paper, the redundancy and mutual information are explored to multi-dimensional categorical data. It is found that the redundancy for categorical data could be expressed as the function of the generalized likelihood ratio statistic under several kinds of independent log-linear models, so that the redundancy could also be used to analyze contingency tables. Whereas the generalized likelihood ratio statistic to test the goodness-of-fit of the log-linear models is sensitive to the sample size, the redundancy for categorical data does not depend on sample size but its cell probabilities itself.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2534-2536
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• 2001

The most of metalhalide lamp is what the momentary restarting cannot be realized when the arc tube is in the hot condition. But if the lamp is restarted in the hot conditidn, we must supply the high voltage pulse with 15kv between the both electrodes of lamp. The proposed ignitor has two ignitors. If we connect each ignitor at the both sides, the high voltages of two different frequencies are generated. if so, when the one of the ignitor generates the highest voltage and the other applied generates the lowest voltage. At this time, the widest difference of voltage is applied to electrodes of the lamp. In this way, we can restart the lamp with the voltage 15kv, even if the lamp is in the hot condition.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2005년도 춘계학술발표대회 논문집
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• pp.159-163
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• 2005

The purpose of this study was to analyze the relationship between the product characteristics and spatial configuration in a retail store. This study utilized the analytical method of Space Syntax, and the software package used for the analysis was New-wave and Pesh. The qualitative study focused on the showroom of 'H INTERIOR', a leading furniture company in Korea, and examined the accessibility of the space. The result showed that the main accessible route was well established in the retail store, and more trendy and fashionable products were likely to be displayed in more accessible places. Also, the products in the selected showroom were arranged according to the pricing information, so that products with lower price were displayed in more accessible places. This study suggested that it be important to adequately and appropriately display the products in relation to the characteristics of products, and implied that the method of Space Syntax was useful to strategically evaluate the display in retail spaces.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.378-382
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• 2004

This paper gives information which is applied to install the electrical equipment of amusement park and ride. For analyzing the standard of electrical equipment installation, we research the related regulation of National Electrical Code(2002), IEC 60364-series and Technical standards for Electrical facilities of internal standard. Among electrical equipments of amusement park and ride, especially we study the transformer vaults, overcurrent protection and ground protection of electrical equipment. So we the furnished the installation information of transformer vaults, overcurrent and ground protection at amusement park and ride.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.205-209
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• 2004

The metal halide lamps are now widely used in the application and commercial lighting due to their attracting properties such as good color rendering and high efficiency. But they have the serious problem of acoustic resonance for high frequency operation and they need the high voltage to ignite. So, they have not been applied to indoors. Over the past few years, a considerable number of studies have been conducted on the electronic ballast together with hot restarting and resonance phenomenon. But very few attempts have been made with the adaptive ignition method according to the lamp state. In this paper, electronic ballast is proposed for metal halide lamps with an igniter for adaptive ignition. The proposed electronic ballast can generate different ignition voltages according to the arc tube state.

• 한국농촌건축학회논문집
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• 제1권1호
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• pp.107-114
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• 1999

The purpose of this study is to suggest types and a model of utilization of abolished school as facilities of the aged in rural area. There are various types of abolished school. One of them is the facilities of the aged. It is not general type, but special case according to regions. So, this study is focused on the possibility of utilization for it. We expect that abolished school make an offer a type of facilities of the aged. By surveying exterior and interior space, and analysing the actual conditions of facilities and data of various types, I propose types of abolished school, design factors and model of using facilities of the aged.