• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.200-204
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• 2012

In engineering hydrology, an estimation of precipitation loss is one of the most important issues for successful modeling to forecast flooding or evaluate water resources for both surface and subsurface flows in a watershed. An accurate estimation of precipitation loss is required for successful implementation of rainfall-runoff models. Precipitation loss or hydrological abstraction may be defined as the portion of the precipitation that does not contribute to the direct runoff. It may consist of several loss elements or abstractions of precipitation such as infiltration, depression storage, evaporation or evapotranspiration, and interception. A composite loss rate model that combines four loss rates over time is derived as a lumped form of a continuous time function for a storm event. The composite loss rate model developed is an exponential model similar to Horton's infiltration model, but its parameters have different meanings. In this model, the initial loss rate is related to antecedent precipitation amounts prior to a storm event, and the decay factor of the loss rate is a composite decay of four losses.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제8권2호
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• pp.273-286
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• 1997

본 연구는 주의력결핍 ${\cdot}$ 과잉행동장애 환아에서 사건관련전위와 연속과제수행에 대한 methylphenidate(MPH)의 영향을 평가하고 사건관련전위의 변화와 연속과제수행의 변화 사이의 상관성을 알아보고자 시행되었다. 11명의 주의력결핍 ${\cdot}$ 과잉행동장애 남아에서 MPH(0.5mg/kg)의 급성효과를 알아보기위하여 사건관련전위와 연속과제수행검사를 시행하여 다음과 같은 결과를 얻었다. 약물 투여후, Fz에서 표준자극에 대한 P3 잠복기가 유의하게 감소하였고 Pz, Oz에서 표적자극에 대한 P2 진폭, 그리고 Cz에서 표적자극에 대한 P3 진폭이 유의하게 증가하였다. 또한 CPT-X 파라다임에서 탈락수와 오보수, 그리고 CPT-AX 파라다임에서 오보수가 유의하게 감소하였으며 CPT-X 파라다임의 반응의 정확도(the number of correct responses to targets, Hits)와 민감도(Perceptual sensitivity, d') 그리고 CPT-AX 파라다임의 민감도가 유의하게 증가하였다. 마지막으로 Fz에서 표적자극에 대한 P3 잠복기의 변화와 CPT-AX 파라다임의 민감도의 변화사이에는 음의 상관(p<0.05)이 있었고 Pz에서의 표적자극에 대한 P2 진폭의 변화와 CPT-X 파라다임의 민감도의 변화 사이에는 유의한 양의 상관(p<0.05)이 있었다. 결론적으로 MPH는 주의력결핍 ${\cdot}$ 과잉행동장애 아동에서 변화지향반응, 과제와 연관된 자극에 대한 반응, 정확도, 민감도를 개선시키며 비표적자극으로부터 표적자극을 구별하는 능력의 증가는 큰 기억요소를 요하는 과제에서는 자극 평가시간의 단축을 반영하며 단순과제에서는 변화지향반응의 개선을 반영하는 것으로 나타났다.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2006년도 추계학술대회
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• pp.327-336
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• 2006

The odds ratio is used for assessing the disease-exposure association, because epidemiological data for case-control of cohort studies are often summarized into 2 ${\times}$ 2 tables. In this paper we define the odds ratio function(ORF) that extends odds ratio used on discrete survival event data to continuous survival time data and propose estimation procedures with censored data. The first one is a nonparametric estimator based on the Nelson-Aalen estimator of comulative hazard function, and the others are obtained using the concept of empirical odds ratio. Asymptotic properties such as consistency and weak convergence results are also provided. The ORF provides a simple interpretation and is comparable to survival function or comulative hazard function in comparing two groups. The mean square errors are investigated via Monte Carlo simulation. The result are finally illustrated using the Melanoma data.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.458-461
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• 2007

Recently, the continuous welded rail(CWR) track has been used for less maintenance of the High-speed railway tracks. In case of CWR track, track buckling has always been an unpredictable event under the high compressive stress in rail. The behavior and stress state of CWR track is manily influenced by its thermal variations, and it is important to understand seasonal variations of rail temperature and stress to predict the track stability. This paper describes the in-site measurement for the rail temperature and rail stress, and the correlation between the rail temperature and stress was examined.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.2110-2111
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• 2008

Continuous on-line temperature monitoring allows corrective measures to be taken to prevent upcoming failure. Continuous temperature monitoring and event recording provides information on the energized equipment's response to normal and emergency conditions. On-line temperature monitoring helps to coordinate equipment specifications and ratings, determine the real limits of the monitored equipment and optimize facility operations. Using wireless technique eliminates any need for special cables and wires with lower installation costs if compared to other types of online condition monitoring equipment. In addition, wireless temperature monitoring works well under difficult conditions in strategically important locations. Wireless technology for on-line condition monitoring of energized equipment is applicable both as standalone system and with an interface with power quality monitoring system.

• 전력전자학회논문지
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• 제24권3호
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• pp.207-214
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• 2019

In this study, discrete-time domain analysis is proposed to investigate the input current of a buck AC/DC light-emitting diode (LED) driver. The buck power factor correction converter can operate in both discontinuous conduction mode (DCM) and continuous conduction mode (CCM). Two discontinuous and two continuous conduction operating modes are possible depending on which event terminates the conduction of the main switch in a switching cycle. All four operating modes are considered in the discrete-time domain analysis. The peak current-mode control with slope compensation is used to design a low-cost AC/DC LED driver. A slope compensation design of the buck AC/DC LED driver is described on the basis of a discrete-time domain analysis. Experimental results are presented to confirm the usefulness of the proposed analysis.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 추계학술대회
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• pp.129-132
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• 2010

인터넷의 발전으로 사용자는 방대한 양의 데이터로부터 유용한 정보를 획득할 수 있다. 이러한 데이터는 스트림 데이터와 유사하게 연속적으로 발생하기 때문에 사용자의 요구에 맞는 정보만을 추출하기 위한 효율적인 기법이 필요하다. 전통적인 정보 추출 방법은 사용자의 요구를 질의로 변환하여 대용량의 데이터를 대상으로 처리하였다. 그러나 이 방법은 연속적으로 변화하는 데이터를 대상으로 매번 사용자의 질의를 처리하기 때문에 비효율적이다. 이 논문에서는 인터넷에서 발생하는 데이터의 변화를 이벤트로 표현하고, 사용자의 요구사항을 프로파일로 정의한 이벤트-프로파일 모델을 제안한다. 그리고 이 모델을 기반으로 이벤트와 프로파일을 효율적으로 처리하기 위한 여과방법을 제안한다. 또한 제안된 모델을 기반으로 시스템을 구현하고 다양한 데이터 셋을 대상으로 실험평가를 실시하여 제안하는 방법의 우수성을 입증한다.

• 한국정보통신학회논문지
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• 제15권8호
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• pp.1750-1755
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• 2011

최근 다양한 정보검색 기법의 발달로 인해 사용자는 인터넷으로부터 유용한 데이터를 쉽게 획득할 수 있다. 이러한 데이터는 스트림 데이터와 유사하게 연속적으로 발생하기 때문에 인터넷에서 발생하는 대량의 데이터 중에서 사용자의 요구에 맞는 데이터만을 추출하기 위한 기법이 필요하다. 전통적인 데이터 추출 방법에서는 데이터를 먼저 데이터베이스에 저장한 후에 사용자의 요구를 질의로 변환하여 처리하였다. 그러나 이러한 방법은 연속적으로 발생하는 대용량의 데이터에 대하여 사용자 질의를 처리하는 경우에 비효율적인 문제가 있다. 이 논문에서는 인터넷에서 발생하는 데이터의 변화를 이벤트로 표현하고, 사용자의 요구사항을 프로파일로 정의한 이벤트-프로파일 모델을 제안한다. 그리고 이 모델을 기반으로 이벤트와 프로파일을 효율적으로 처리하기 위한 여과방법을 제안한다. 또한 제안된 모델을 기반으로 시스템을 구현하고 다양한 데이터 셋을 대상으로 실험평가를 실시하여 제안하는 방법의 우수성을 입증한다.

• 한국농공학회논문집
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• 제62권4호
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• pp.13-22
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• 2020

The Doam Lake watershed has a significant impact on the downstream water system due to nutrients and sediment outflow during rainfall caused by steep slopes, soil losses, and fertilization. These non-point sources are unclear in the discharge area and are affected by land use patterns, soil characteristics, and topographical features of the watershed. Therefore, this study conducted rainfall monitoring from July to October 2019 in Songcheon upstream of the Doam Lake watershed, one of the non-point pollution source management areas. Then, after analyzing rainfall runoff, Event Mean Concentration (EMC) and Mass First Flush ratio (MFFn) were calculated to compare and analyze the characteristics of rainfall and the non-point pollutant discharge. As a result of the analysis, it showed various non-point pollutant emission characteristics for each rainfall event. In addition, the concentration of EMC and the MFFn were affected by the average rainfall intensity and the maximum rainfall intensity, and were not significantly affected by the number of antecedent drying days. In the future, it is expected that effective non-point source reduction measures and management measures according to rainfall intensity through continuous monitoring and analysis will be needed.

• 한국연극학
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• 제48호
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• pp.549-569
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• 2012

Since 1995, the Local autonomy era has opened, local festivals have been increasing throughout the country. Traditional culture festivals are also increasing. Performing traditional culture festivals is effective for maintenance and transmission of traditional culture as well as creation and nurturing of local culture. They are also effective promoting local economy. Depending on realization level of character, place and costume based on historic research, traditional culture festivals are classified as the "Representation event" or the "Reenactment event". But there are two problems. The first is unexacting classification method for festival types made by Central government yearly. The second is unable to meet one of two goals which are protecting traditional culture and stimulating local economy throughout increasing tourists. The purpose of this study is to suggest improvement of classification method for festival types, and to offer two suggestions for ensure successful local festivals. First of all, I suggest advanced classification method for festival types. For more sophisticated collection process of national festival status, local government department should ensure purpose of festivals, and central government department should add 3 steps to existing process. For example professional committee for judgement of festival types should be founded for consulting of local and central government department. The second suggestion is reinforcement of historic research for the Representation of traditional culture event. The representation of traditional culture should focus on protection of tradition, and could be perfect by continuous historic research. The last suggestion is cooperation with local governments each other for the Reenactment of traditional culture event. The Reenactment of traditional culture should focus on promoting local economy by increasing tourists. So local governments who have similar traditional events should cooperate to get preventing loss of resource and overcome weakness of promoting.