• Journal of Power Electronics
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• 제15권4호
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• pp.1085-1092
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• 2015

In this paper, the expressions of the estimated information of a single-phase enhanced phase-locked loop (EPLL), when input signal contains harmonics and a DC offset while the fundamental component takes step changes, are derived. The theoretical analysis results indicate that in the estimated information, the n^th-order harmonics cause n+1^th-order periodic ripples, and the DC offset causes a periodic ripple at the fundamental frequency. Step changes of the amplitude, phase angle and frequency of the fundamental component cause a transient periodic ripple at twice the frequency. These periodic ripples deteriorate the performance of the EPLL. A hybrid filter based EPLL (HF-EPLL) is proposed to eliminate these periodic ripples. A delay signal cancellation filter is set at the input of the EPLL to cancel the DC offset and even-order harmonics. A sliding Goertzel transform-based filter is introduced into the amplitude estimation loop and frequency estimation loop to eliminate the periodic ripples caused by the residual input odd-order harmonics and step change of the input fundamental component. The parameter design rules of the two filters are discussed in detail. Experimental waveforms of both the conventional EPLL and the proposed HF-EPLL are given and compared with each other to verify the theoretical analysis and advantages of the proposed HF-EPLL.

• 대한한의학원전학회지
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• 제20권4호
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• pp.251-265
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• 2007

This study is a research on the etiology in Wu Youke's wenyi theory. In regard to the etiology of epidemic disease that had been spread on a very large scale at that time, Wu Youke denied the traditional theory which urged the irregular change of climate as the cause of epidemic disease, and proposed the concept of 'zaqi' which was considered by him to be something that could be the real cause of epidemic disease. And He treated the wenyi disease as something that has the same meaning with wenbing, so his concept on wenbing was basically the thing that treats 'zaqi' as the fundamental cause of wenbing and treats the concept of 'wen(溫)' as an environmental cause that could help activate the virulence of 'zaqi'. Such concept like this was the thing somewhat different from the traditional etiological theory that considers the change of climate as the principal cause of waigan(外感)-disease, and it must for the most part have been originated from the experience of Wu Youke himself. But this study, in contrast, based on the thing he denied the traditional theory on the irregular change of climate, has been done in the point of view that fundamental concept of his wenyi theory such as 'zaqi' was not only originated from his clinical experience but also from the influence of paradigm shift in the natural philosophy of that time. There had been so much change in cosmology and natural philosophy from the fundamental basis at that time, and the the most principal concept of it was that there always exists irregular faces in the change of nature. Such concept like this got into its stride from about 17th century, and it was expressed in the form of the severe criticism against the traditional natural philosophy. In regard to this, this study has outlined the academic thought of the leading scholars who made a significant progress in such a paradigm shift, and it includes the scholars like Wang Tingxiang, Wang Fuzhi, Hu Wei, Huang Zongxi, who played their role in the time of the latter period of Ming dynasty and the former period of Qing dynasty.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제15권2호
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• pp.31-38
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• 2009

The purpose of this study is to research the fundamental cause of psychological stress and healing elements related to the waterscape design of contemporary architecture. As one of the solution, analysis of the psychological function of waterscape of natural elements in composition of architectural space was included. This study is focused on the form and psychological function of waterscape, and concerned with the cause of psychological stress at the same time. Also, this study includes analyzed cased with both inside and outside of contemporary architecture. The result will show that the waterscape will be useful solution for healing of fundamental cause of psychological stress with sixteen psychological healing elements through compositional elements of waterscape.

• 산업기술연구
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• 제2권
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• pp.61-67
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• 1982

The cause of efflorescence originated from calciumsilicate hydrate brick was studied and some reports on efflorescence were reviewed. The main ingredient of undesirable efflorescence powder was sodium sulphate. It was found that influx of sodium and sulphur components was resulted from hydration water and fine sand.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2012년 춘계학술대회
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• pp.35-41
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• 2012

The unsafe act and unsafe condition is induced by the fundamental cause factors of industrial accidents. In this paper, stress is classified into job, life and workplace stress. Therefore, the purpose of this paper is to develop a Korean stress model focused on the unmarried workers in order to prevent fundamental industrial accidents. The results of this paper are followed. First, the oriental culture and idea in Korea is directly connected to the central axis of all life. Accordingly, concrete and systematic safety management methods should be proposed from the point of Korean culture. Finally, the industrial accident questionnaire needs an item that reports the mental and physical condition of workers in order to prevent occupational diseases.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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• pp.375-382
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• 1999

The fundamental vibration period of a shearwall apartments cannot estimate accurately by means of empirical formulas specified in present codes, The objective of this paper is to estimate the period of a shearwall apartments by microtremor measurement. A micretremor is the continuous small oscillation of the ground cause by traffic and operation machinery. Microtremors are extensively studied primarily in Japan to estimate conveniently subsurface structures of soil deposits and building vibrations. It is obtained the results that the fundamental periods estimated by microtremor measurement are shorter than those values by dynamic analysis of building.

• 한국안전학회지
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• 제4권1호
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• pp.83-90
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• 1989

Recently, due to the increase of 220V distribution lines and equipments preventive measures to cope with several kinds of electric accidents is revealed as an urgent problem. This study investigates the following matters; the cause and present condition of e1ectric shock accident, the influence of electric shock on human body, the safety limit of electric shock, the method of distribution voltage, the insulation of electrical load apparatus, the teachnics of electric shock prevention and foreign materials concerned with this subject etc. This paper present the fundamental cause of electric shock and syntbetic preventive counter measure of electric shock, too.

• Nuclear Engineering and Technology
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• 제49권1호
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• pp.71-81
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• 2017

When an integral pressurized water reactor is operated under low power conditions, once-through steam generator group operation strategy is applied. However, group operation strategy will cause nonuniform coolant flow distribution at the core inlet and lower plenum. To help coolant flow mix more uniformly, a flow mixing chamber (FMC) has been designed. In this paper, computational fluid dynamics methods have been used to investigate the coolant distribution by the effect of FMC. Velocity and temperature characteristics under different low power conditions and optimized FMC configuration have been analyzed. The results illustrate that the FMC can help improve the nonuniform coolant temperature distribution at the core inlet effectively; at the same time, the FMC will induce more resistance in the downcomer and lower plenum.

• Korean Journal of Acupuncture
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• 제17권1호
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• pp.123-140
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• 2000

The purpose of this study is to understand the special character and the tendency of the movement change that 12 meridians possess. We studied about the incidental and fundamental rule of the six atmospheric influence that was presented by Pyobonjoong(the incidental, fundamental, intermediate) theory, and the Hwang won-uh's the Six Channel activity of the Qi theory that presented movement form of the meridian through the six atmospheric influence. Then we found the following substances. The Pyobonjoong(the incidental, fundamental, intermediate) theory is applicable to understand the special character and the tendency of the movement change that Meridians possess. But, because the Pyobonjoong(the incidental, fundamental, intermediate) theory can't classify the characteristic difference of the hand and foot meridians, then the principle that can devide the meridians of the hand and foot, must be supplied. The Jungwha(right changing)-Daewha(opposite changing) theory is able to concretely classify the special character of the hand and foot six meridians. And Hwang's Shawha(superintending change)-Jongwha(following change) theory that is base on Jungwha(right changing)-Daewha(opposite changing) theory, is able to classify the special character of the hand and foot six meridians, too. If the concept of the Meridians is understood by the Shawha(superintending change)-Jongwha(following change) theory, the special character of the hand and foot six meridians could be concretely classified and then the meridian of the Bowels and the six atmospheric influence corresponded to the meridians could be expansively explained as the point that take charge and control these special Qi in the human body The Bon-Qi(fundamental Qi) act on the special character of Shawha(superintending change) six meridians and the tendency of the movement change is cause by the insufficiency and excessiveness of the Bon-Qi(fundamental Qi). The Qi of the Shawha(superintending change) meridians act on the special character of Jongwha(following change) six meridians and the tendency of the movement change is cause by the exuberance of Yang and the deficiency of Yang.

• 동의신경정신과학회지
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• 제15권2호
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• pp.11-22
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• 2004

Objects : This study was aimed to investigate relation to the Psychologic factor and Mental disorder of Women. Methods : Research data is based on Booindaejoenyangbang(婦人大全良方) and Dongyipogam(東醫寶鑑). And study the psycho elements in Mental disorder of Women. Results : 1. Psychologic factor have a part in A cause for mental disorder of women, certainly. 2. The weakness is fundamental cause for mental disorder of women and the Wind is an immediate cause frequently. 3. Most mental disorder of women develop severe psychiatric symptoms. 4. Psychologic factor is concerned to causing and symptoms at various diseases of women. Conclusion : The results suggest that women is delicate at the psychologic factor, so mental disorders are taken easily.