• Transactions on Electrical and Electronic Materials
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• 제9권5호
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• pp.213-219
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• 2008

Pulse waves continuously change with respect to the characteristics and status of the cardiovascular system and in relation to the blood pressure (BP) and the pulse wave velocity (PWV). Monitoring the vascular condition by analyzing the variations in pulse waveforms has been used to diagnose vascular disorders and in drug treatment of arteriosclerosis and peripheral circulatory obstruction. In this paper, we investigated the vascular characteristic index with regard to the BP and classified by pulse wave signals. The pressure pulse wave and photoplethysmography (PPG) were measured simultaneously while subjects exercised, producing changes in the BP, to analyze the variation in the vascular characteristic index. We investigated the correlation between the BP and vascular characteristic index with regard to the classification methods of the pulse wave. The reflection index (RI) and vascular stiffness index were correlated with the diastolic BP, but no correlation was found between these parameters and the systolic BP. These results suggest the possibility of estimating BP through simple measurements of pulse waves.

• 상하수도학회지
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• 제20권3호
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• pp.451-460
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• 2006

While sludge settles down in a batch column, sludge concentration becomes high. Sludge concentration change is one of the most critical causes of the sludge settling velocity variation. Therefore, sludge concentration change causes sludge index to change. SVI is more sensitive than other sludge indexes to the change of sludge concentration. And if sludge-water interface has reached final height within 30minutes, SVI is not suitable for prediction of sludge settling characteristic, Therefore, SVIs of each sludge are, in some cases, different although each sludge has the same settling velocity. But SVI has been widely used to interpret sludge settling characteristic by a simple testing method. This work has two purposes. The first purpose is to predict sludge settling velocity by using sludge-water interface settling velocity. And the second purpose is to develop new sludge settling characteristic index to exactly interpret sludge settling characteristic by overcoming the limit of SVI.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.434-438
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• 2004

This paper has proposed presumable method of ergonomics estimate index from evoked potential of visual stimulation for establishment a fixed ergonomics estimate index. The proposed method presumes continuance time and amplitude of ergonomics using prony method. Band characteristic of alpha and beta band, and that of background and evoked potential was analyzed using FFT method. And, that were presumed continuance time and amplitude of ergonomics using porny method. As a result of that proposed method presumed band characteristic, continuance time and amplitude of ergonomics, classification of ergonomics of impatient, rage and fear were practicable.

• 한국수자원학회논문집
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• 제41권6호
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• pp.605-617
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• 2008

본 연구에서는 우리나라 홍수유출의 특성을 종합적으로 표현할 수 있는 홍수지수를 개발하였다. 홍수유출특성을 종합적으로 지수에 반영하기 위하여 유출곡선으로 표현되는 홍수유출의 특성을 홍수수문곡선의 상승률, 첨두유량, 홍수 응답시간, 첨두발생 전 홍수용적 등 4가지의 특성인자로 표현하였다. 이러한 유출특성인자를 객관적인 상대심도로 표현하기 위하여 본 연구에서는 특성인자의 분포함수를 표준정규분포함수로 변환하여 특성지수를 산정하였다. 본 연구에서 산정한 종합홍수지수(Comprehensive Flood Index, CFI)는 기존의 돌발홍수지수(Flash Flood Index, FFI)의 문제점을 보완한 것으로 홍수의 심도를 유역별로 상대평가할 수 있는 특징이 있다. 본 연구에서는 한강과 설마천 유역에 대하여 CFI를 산정하고, 상관분석과 회귀분석을 통해 FFI와 비교 평가하였다. CFI는 산정과정에서 특정 홍수유출 특성에 지배받지 않아 종합적으로 홍수유출특성을 표현할 수 있고, FFI에 비해 강우-유출관계를 효과적으로 설명할 수 있었다.

• 한국환경생태학회지
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• 제25권3호
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• pp.389-403
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• 2011

인간 활동이 생태계의 훼손과 생물다양성의 변화에 미치는 영향을 경관생태학적 측면에서 분석하고 해석하는 연구가 활발히 진행되고 있다. 본 연구는 우리나라의 35개 농촌마을을 대상으로 자연생태계의 교란정도를 알 수 있는 귀화식물분포현황을 조사하였다. 대상지에 대한 토지이용 현황도를 제작하고 이를 바탕으로 경관지수를 이용하여 경관생태학적특성을 정량화하였다. 이를 바탕으로 대상지의 경관지수와 귀화식물 분포특성의 상관관계를 분석하였다. 경관지수는 공간분석 프로그램인 FRAGSTATS를 이용하여 산출하였으며 귀화식물의 분포특성은 Urbanization Index와 Naturalization Index를 이용하였다. 연구 결과 귀화율과 패치밀도, 귀화율과 가장자리밀도, 귀화율과 면적가중평균형태지수 등이 양의 상관관계를 나타냈으며 귀화율과 핵심면적백분율, 귀화율과 평균핵심지역 등이 음의 상관관계가 있는 것으로 분석되었다.

• 한국정밀공학회지
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• 제21권12호
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• pp.37-43
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• 2004

The performance of magnetic abrasive finishing fur surface is evaluated by the characteristic curve. The characteristic curve is generated by experiment in surface finishing. For experiment, new magnetic inductor is designed and manufactured. 15 kinds of powders are provided to find the relationship between powder characteristic and finishing performance. As powder, Fe-TiC. Polymer-TiC and Fe-NbC are used with different size. The size of abrasives and location are also important factor for the performance. From characteristic curve, two index are obtained, which specify the initial finishing performance and endurance of finishing performance. It is proved that the performance index can be applied to select proper powder for efficient deburring. It is shown that the characteristic curve can be used as good tools for evaluating powder performance in surface finishing and deburring.

• 충청수학회지
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• 제19권2호
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• pp.123-131
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• 2006

In this paper, a numerical programming for Liapunov index of differential equations with periodic coefficients depending on parameters is given. The associated equations are given at first, then existence of periodic solutions to the associated equations is proved in this paper. And we compute periodic solution u(t) of the associated equations. Finally, we give the error of approximate calculation.

• 제어로봇시스템학회논문지
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• 제21권3호
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• pp.210-216
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• 2015

This paper proposes a method to determine vehicle driving state using the driving characteristics index. This index is a quantitative value to classify the driving state of a vehicle with its velocity and heading angle in that instant. It can classify driving state into straight driving, lane changing driving and curve driving in real time. In addition, the number of positional information is movably set up by designed region of interest. The proposed index is expressed on the stable driving states. Each driving state has characteristic tendency, and is compared with index distributional areas. The proposed method is verified by the actual driving experiment on the KATECH proving ground.

• 건축역사연구
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• 제21권2호
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• pp.37-52
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• 2012

This research has set up the fire fighting general index for Fire fighting of Crowded Wooden Building Cultural Asset which is composed of traditional wooden building instinct or complex. The results of this study are as follows. First, Fire fighting general index for crowded wooden building cultural asset, it is necessary to set fire fighting priority by considering fire risk and cultural asset characteristic and establish the system to cope with fire disaster in the most effective way by arranging facilities with restricted resource. Second, Fire risk is the index to draw fire and spread risk of cultural asset by applying index calculation processes such as fire load, burning velocity and ignition material spread characteristic to various aspects such as individual building and complex and combining their results. Cultural asset importance index consists of individual building evaluation, publicity security degree, area importance evaluation and historical landscape degree evaluation. Third, for each index combination process, weight of each index is drawn on the basis of AHP analysis result that is performed to the specialists of related fields. The formula to apply and combine it is prepared to apply the model to include meaning of each index and comparative importance degree.

• 전기학회논문지
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• 제57권9호
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• pp.1500-1506
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• 2008

In this paper, we proposed new reliability characteristic curve, which-can clearly show reliability property of transmission and substation system considering uncertainty such as frequency and duration of device fault. It express the relationship of duration of load curtailments, demand not supplied, and energy not served as “ y = $ax^{-1}$ " curve. and we proposed the method, which can objectively assess reliability of transmission and substation system using proposed characteristic curve as new reliability index. In this method, we used energy index of reliability(EIR) as a criterion of assessment. Finally, we performed a variety of case study for KEPCO system in order to verify usefulness of proposed method.