• 한국해양공학회지
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• 제17권2호
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• pp.67-71
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• 2003

Using motions (Maruo) and wave reflection (the author), speed loss due to wind (van Berlekom) and ITTC standard spectrum, and various effects of weather(:such as weather intensity, ship type, ship size and draught) on ship speed performance at sea were investigated. Further, a comparison of the relative effects of weather and hull roughness on speed loss was also studied for a VLCC.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 추계학술대회(제116회) 및 13회 Workshop 제3회 한ㆍ일 치과보존학회 공동학술대회 초록집
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• pp.586.2-586
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• 2001

The selection of a curing light is a multifactorial decision. While each method of polymerization presents unique clinical benefits, the optimal light-curing technique remains to be determined. The objective of this study was to check the difference of micro hardness and microleakage according to various light intensity (50, 100, 200, 300, 400, 600 ㎽/$\textrm{cm}^2$) and curing time (10, 20, 40 seconds). A3 color of two composite resin, hybrid type DenFil and submicron type Esthet X were tested.(중략)

• 대한토목학회논문집
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• 제13권2호
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• pp.183-190
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• 1993

강우현상은 지역별로 그 특성이 다르고, 장기간을 관측하여 보면 강우특성도 전에 비해서 많이 변화하므로 보다 정확한 배수계획의 수립이나 수공구조물계획을 위해서는 그 지역의 최근의 관측자료까지 포함한 강우특성을 연구하여 적용하는 것이 바람직하다. 따라서 제주지방의 주요 우량관측소(제주시, 서귀포, 성산포)의 최근 20년간(年間)의 자기우량기록지에서 연최대(年最大) 강우량만을 골라서 우량지속기간별로 실측우량을 발췌하였으며, 강우강도식은 일반적으로 많이 사용하고 있는 Talbot형(型), Sherman형(型), Japanese형(型)에다 새로운 Semi-log형(型)을 추가해서 제주지방의 지역별 최적확률 강우강도식을 유도해 본 결과 제주시는 확률년이 3년(年)~5년(年)에는 Japanese형(型), 그 외는 Talbot형(型)이고, 서귀포는 Sherman형(型), 성산포는 Talbot형(型)으로 나타났다.

• 한국수자원학회논문집
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• 제39권6호
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• pp.521-531
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• 2006

본 논문은 최근 발생한 집중호우와 이상강우를 고려하며 인천지역에서 사용중인 확률강우강도식에 대한 새로운 확률강우강도식을 제안하였으며, 기상청 자료를 이용하여 지속시간 10분$\sim$24시간까지의 임의시간 연최대강우량을 산정하였다. 강우지속기간별 확률강우량을 추정하기 위하여 개의 확률분포형을 적용하였으며 Chi-square 검정방법, Kolmogorov-Smirnov 검정방법, framer Von Mises 검정방법으로 적합도 검정과 함께 최근 강우에 대한 경향을 분석하고 실제 발생한 강우 중에서 최대 발생 강우량을 고려하여 적정분포인 GEV 분포를 확률 분포형으로 선정하였다. 확률강우강도식은 최소자승법을 사용하여 Talbot형, Sherman형, Japanese형, 통합형 I 및 II 형태로 산정하였고, 지역내 하수도 및 하천의 지속시간을 감안하여 확률강우강도식을 결정하였다. 또한 정확성을 고려하여 통합형 I을 선택하였고 지속시간에 따른 강우강도식의 확률강우와 관측치를 감안한 강도식을 인천지역의 강우강도식으로 제안하였다.

• 경영과정보연구
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• 제38권1호
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• pp.1-21
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• 2019

본 연구는 최고경영자와 이사회의 네트워크밀도와 R&D투자 간의 관계와 이들 관계에 영향을 미칠 수 있는 기업분할의 유형과 제도의 영향을 분석하는데 주된 목적을 두고 실행되었다. 연구목적의 달성을 위해 외환위기가 발생하고 기업분할 관련법(상법 530조)이 제정된 직후인 1999년부터 가장 최근의 자료수집이 가능한 2016년까지 총 18년의 연구기간 동안 기업분할을 실행한 국내기업들을 대상으로 다중회귀분석을 실행하였다, 분석결과는 국내기업 최고경영자와 이사회의 네트워크밀도와 R&D투자 간에 유의한 정(+)의 관계가 있음을 보여주고 있다. 또한 기업분할 유형과 관련하여 최고경영자와 이사회의 네트워크밀도와 R&D투자 간의 정의 관계는 비관련분할에서 보다 관련분할을 실행한 기업에서 강화되었음을 보여주고 있으며, 기업분할 제도와 관련해서는 물적분할보다 인적분할을 실행한 기업들에서 이들 관계가 강화되었음을 보여주고 있다. 신속한 의사결정이 요구되는 사안임에도 불구하고 장기적인 관점에서 높은 수준의 불확실성과 위험을 수반하게 되는 R&D투자결정에 있어 최고경영자와 이사회 간의 네트워크밀도가 긍정적인 영향을 미칠 수 있음을 보여주는 본 연구의 분석결과는 최고경영진들 간의 신뢰의 중요성을 강조해 온 네트워크이론의 주장과 일치한다. 또한 혁신역량 강화를 위한 R&D투자결정에 있어 개인수준의 요인들뿐만 아니라 조직수준의 요인이 함께 고려되어야 함을 시사하고 있다. 본 연구는 향후 기업분할의 활용을 통한 보다 전략적인 국내기업 지배구조의 개선방안에 대한 연구를 강화하는 동기를 제공해 줄 수 있을 것으로 기대된다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2000년도 추계학술발표회 초록집
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• pp.1-2
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• 2000

In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the onventional rotating barrel, vibrational barrel(vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components. The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed thatbthe average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value. Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components. However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. 2H20 + e $\rightarrow$M/TEX> 20H + H2.. Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure there by resulting to bad plating condition.

• 대기
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• 제29권4호
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• pp.381-390
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• 2019

This study investigates the impacts of urban land-use fraction and temperature advection on the urban heat island intensity over the Seoul metropolitan area using the UM (Unified Model) with the MORUSES (Met Office Reading Urban Surface Exchange Scheme) during the heat wave over the region from 2 to 8, August 2016. Two simulations are performed with two different land-use type, the urban (urban simulation) and the urban surfaces replaced with grass (rural simulation), in order to calculate the urban heat island intensity defined as the 1.5-m temperature difference between the urban and the rural simulations. The land-use type for the urban simulation is obtained from Korea Ministry of Environment (2007) land-use data after it is converted into the types used in the UM. It is found that the urban heat island intensity over high urban-fraction regions in the metropolitan area is as large as 1℃ in daytime and 3.2℃ in nighttime, i.e., the effects of urban heat island is much larger for night than day. It is also found that the magnitude of urban heat island intensity increases linearly with urban land-use fraction. Spatially, the estimated the urban heat island intensities are systematically larger in the downwind regions of the metropolitan area than in the upwind area due to the effects of temperature advection. Results of this study indicate that urban surface fraction in the city area and temperature advection play a key role in determining the spatial distribution and magnitude of urban heat island intensity.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.660-663
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• 2006

Rainfall estimation is important to weather forecast, flood control, hydrological plan. The empirical and statistical methods by measured data(surface rain gauge, rainfall radar, Satellite) is commonly used for rainfall estimation. In this study, the rainfall intensity for East Asia region was estimated using the empirical relationship between SSM/I data of DMSP satellite and brightness temperature of GEOS-9(10.7${\mu}m$) with cloud types(ISCCP and MSG classification). And the empirical formula for rainfall estimation was produced by PMM (Probability Matching Method).

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2468-2473
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• 2005

Because the rain gauges of tipping bucket type can easily use the digital signal, the rain gauges are widely used for the meteorological observation. In general, the resolution of rain gauges of tipping bucket type can be categorized by the 0.1mm, 0.5mm, and 1.0mm classes. But, the error of the tipping bucket rain gauges is made by the intensity of rainfalls and is expected to make the standard calibration method for error measurement. Thus, we developed the hardware of standard calibration facility for rain gauges by weighting measurement method and proposed the standard procedure by rainfall intensity in this study Also, we calculated the error for the rainfall intensity and obtained useful result through the proposed calibration method.

• 제어로봇시스템학회논문지
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• 제12권8호
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• pp.818-823
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• 2006

Because the rain gauges of tipping bucket type can easily use the digital signal, the rain gauges are widely used for the meteorological observation. In general, the resolution of rain gauges of tipping bucket type can be categorized by the 0.1mm, 0.5mm, and 1.0mm classes. But, the error of the tipping bucket rain gauges is made by the intensity of rainfalls and is expected to make the standard calibration method for error measurement. Thus, we developed the hardware of standard calibration facility for rain gauges by weighting measurement method and proposed the standard procedure by rainfall intensity in this study Also, we calculated the uncertainty for the rainfall intensity and obtained useful result through the proposed calibration method.