• 한국농공학회지
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• 제12권4호
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• pp.2063-2077
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• 1970

The Purpose of this study is to give the hydrologically basic data for the development of water resources in Korea and a quantity of daily average precipitation and its frequency in a year are investigated to study the presumption which is affected to river flow. Characteristics of precipitation is poor as source of water resources compared with its efficiency. So, because of such characteristics of precipitation, river flow also is in harmony and distribution of river flow comes to the result of irregularity, that is, range of river coefficiet between the quantity of maximum river flow and others river flow is big, and it is insufficient as source of water resources. Yearly river flow being expressed by daily unit indicates the ratio(%) of distribution to total yearly river flow, and the model of hydrograph is drawn up. The gives the basis to make yearly water balance sheet. This study is not completed, yet but in forth-coming days, the water will try continuously to give more correct basis for the development of water resources according to a great deal of data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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• pp.266-268
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• 2004

This paper presents the greenhouse gas emission trading scheme which is under progress as a pilot project at the power sector in preparation for UNFCCC. By referring UK's, Emission Trading is introduced incentive auction to maximize the reduction of greenhouse gas emission. At the 1st step, from year 2006 to 2008, only CO2 is regarded as an objective target to decrease but emission credit is excluded with an assumption and only 5 Generation company take part in as participants. The market operating procedure is composed of participants' registration, baseline verification, incentive auction, the registration of initial and yearly allocation, emission trading, yearly emission verification & approval, yearly obligation conformity, carry forward & incentive grant. It can be serve a guideline the whole aspects of emission trading which will start in 2006 including operation, verification and profit sharing.

• 한국농림기상학회지
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• 제4권3호
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• pp.141-150
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• 2002

본 연구는 경기도 가평과 관주 그리고 충청북도 영동에 조성된 잣나무 차대검정림을 대상으로 20년생까지의 연도별 구과 결실량에 미치는 미기후의 영향을 구명하기 위하여 수행되었다. 이를 위해 지역별ㆍ연도별 구과 결실량을 측정하여 분석하였으며, 지형기후학적 방법과 공간통계기법을 사용하여 차대검정림의 연도별 미기후 조건을 추정하여 구과 결실량에 미치는 영향을 분석하였다. 착과수 및 착과 본수를 조사한 결과 가평 지역은 9년생부터, 광주 지역은 10년 생부터 그리고 영동 지역은 이보다 훨씬 늦은 14년생부터 착과가 이루어지기 시작하여 지역별 편차가 있음을 알 수 있었다. 또한 지역별 총 착과수와 가계별 착과수에서도 큰 변이를 나타내고 있는 것으로 파악되었다. 구과 결실량과 지역별 미기후간의 상관분석 결과를 보면 가평 지역의 경우 개화수분 당년의 11월부터 익년 3월까지 5개월 간의 흐린 날수 합계가 높은 부의 상관을 나타내었으며, 광주 지역의 경우 개화수분 당년 6월부터 결실년도 8월까지 15개월 동안의 일조시수 합계가 유의성이 높은 부의 상관을 나타내었다. 한편, 영동 지역의 경우는 개화수분 당년의 11월부터 익년 3월까지의 평균기온 평균치와 개화수분 당년의 5월 평균기온 등에서 부의 상관관계를 인정할 수 있었다. 한편 구과 결실량을 기후지수에 의해 추정하기 위한 최적 회귀식은 지역별로 다양한 기후변수가 채택되었으나 비교적 설명력이 높아 여러 가지 환경 요인 중에서 미기후 조건이 구과 결실량에 영향을 미치는 것으로 판명되었다. 본 연구로부터 얻어진 결과는 잣나무 우량 종자생산에 적합한 입지선정에 필요한 정보로 활용될 수 있을 것으로 기대된다.

• 한국조명전기설비학회지:조명전기설비
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• 제9권5호
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• pp.37-40
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• 1995

In this paper, we investigate the daily load curve and yearly lighting hours of general and industrial Korean lighting apparatus. The daily load curve of lighting apparatus shows the peak use at 8 p.m. in general and 10 a.m. in industrial building. The yearly lighting hours are 2,948 hours in general and 4,066 hors in industrial building.

• 응용통계연구
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• 제21권5호
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• pp.739-754
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• 2008

다중탈퇴모형 연구에서 연(year) 기준의 다중탈퇴율과 연 기준의 절대탈퇴율을 상호 전환하는 방법에 집중되어 있다. 실제 실무에서는 월(month) 기준의 다중탈퇴율이 필요한 경우가 많으므로 본 논문에서는 연 기준의 절대탈퇴율을 월 기준의 다중탈퇴율로 전환하거나 연 기준의 다중탈퇴율을 일 기준의 절대탈퇴율로 전환하는 공식을 유도한다. 유도된 공식은 월 기준 대신에 일(day) 기준 또는 분기(quarter) 기준 또는 반기(semiannual) 기준 등으로도 전환 가능한 공식이다. 또한 월 기준의 절대탈퇴율에서 월 기준의 다중탈퇴율로 전환 가능한 공식도 제시한다. 절대탈퇴율에서 다중탈퇴율로 전환하는 과정에서 절대탈퇴율이 균등분포 가정(UDD: Uniform Distribution of Decrements)을 따른다고 한다. 다중탈퇴율에서 절대탈퇴율로 전환하는 과정에서는 다중탈퇴율이 UDD를 가정하는 경우와 상수탈퇴력 가정 (Constant force assumption)을 따르는 경우로 나누어서 공식을 유도한다. 유도된 공식은 Bowers 등 (1997)에 있는 전환 공식의 일반적인 형태임을 확인할 수 있다. 또한 유도된 공식을 활용하여 수치 예를 통하여 자료를 이용하여 절대탈퇴율과 다중탈퇴율의 전환 과정을 설명하며 유도된 공식들의 차이점을 비교한다.

• 한국농공학회논문집
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• 제59권5호
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• pp.109-126
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• 2017

Universal soil loss equation (USLE) is used to estimate soil loss solely or employed in any hydrologic models. Since soil erosion has been an issue in South Korea for decades, the Ministry of Environment enacted a law to regulate soil erosion in 2012, which is the Notification of topsoil erosion status. The notification is composed of preliminary and field investigations, the preliminary investigation suggests to use USLE and provides USLE factors. However, the USLE factors provided in the notification was prepared at least 10 years ago, therefore it is limited to reflect recent climate changes. Moreover the current yearly USLE approach does not provide an opportunity to consider seasonal variation of soil erosion in South Korea. A GIS-based model was therefore applied to evaluate the yearly USLE approach in the notification. The GIS-based model employs USLE to estimate soil loss, providing an opportunity to estimate monthly soil loss with monthly USLE factor databases. Soil loss was compared in five watersheds, which were Geumgang, Hangang, Nakdonggang, Seomjingang, and Yeongsangang watersheds. The minimum difference was found at Seomjingang watershed, the yearly potential soil loss were 40.15 Mg/ha/yr by the notification approach and 34.42 Mg/ha/yr by the GIS-based model using monthly approach. And, the maximum difference was found at Nakdonggang watershed, the yearly potential soil loss were 27.01 Mg/ha/yr by the notification approach and 10.67 Mg/ha/yr by the GIS-based model using monthly approach. As a part of the study result, it was found that the potential soil loss can be overestimated in the notification approach.

• 한국식생활문화학회지
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• 제29권4호
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• pp.342-347
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• 2014

This survey was conducted to investigate consumer preferences for branded and imported pork, including favorite cooking styles. Data were collected from a total of 252 consumers and analyzed. The results are summarized as follows. Consumers of branded pork showed a moderate preference "moderate" (54%). There was no significant difference in consumer preference for branded pork according to educational level or living area. However, there was a significant difference according to yearly income (p<0.05). Consumers in the high-income group preferred branded pork more than those in the low-income group. Most consumers did not like imported pork (64.6%). There was no significant difference in consumer preference for imported pork according to educational level or living area, whereas there was in the yearly income group (p<0.05). Whereas low-income consumers did not like imported pork, high-income consumers did. The royalty for purchasing of branded pork was shown "3.65" out of 5 points. Whereas there was no significant difference according to educational level, there was for living area and yearly income (p<0.05). Consumers living in large cities or having low income showed high royalty of purchase for branded pork. The royalty for purchase of imported pork was "2.08" out of 5 points. Significant differences for purchase royalty of imported pork were observed according to educational level, living area, and yearly income group (p<0.05). Consumers responded that they liked roasted pork (47.6%). Secondly, consumers liked stew (16.7%). There were no significant differences among various cooking styles in any of the groups.

• The Korean Journal of Ecology
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• 제24권6호
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• pp.335-339
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• 2001

The dynamic model was developed to simulate the photosynthetic rate of Phragmites communis stands in coastal ecosystem. The model was composed of the compartments of both climatic and biological variables. The former were photosynthetic photon flux density(PPFD), daily maximum- and minimum-temperature. The latter were combinations of the specific physiological responses of plant organs with the biomass of each organs. The PPFD and air temperature were calculated and using those values, gas exchange rate of each plant organ was calculated at every hour. The carbon budget was constructed using the modelled predictions. Analysis of annual productivity and fluxes showed that yearly gross population productivity, yearly population respiration and yearly net population productivity were 33.4, 21.3 and 12.1 $CO_2ton{\cdot}ha^{-2}{\cdot}yr^{-1}$, respectively. The final result was tested over two stands, produced promising predictions with regards to the levels of production attained. The model can be used to determine production potential under given climatic conditions and could even be applied to plant canopies with analogous biological characteristics.

• 한국물환경학회지
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• 제23권3호
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• pp.356-366
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• 2007

In this paper a methodology is developed to prioritize replacement of water distribution pipes according to the economical efficiency of replacement and assess the long-term effects of water main replacement policies on water distribution systems. The methodology is implemented with MATLAB to develop a computer algorithm which is used to apply the methodology to a case study water distribution system. A pipe break prediction model is used to estimate future costs of pipe repair and replacement, and the economically optimal replacement time of a pipe is estimated by obtaining the time at which the present worth of the total costs of repair and replacement is minimum. The equation for estimating the present worth of the total cost is modified to reflect the fact that a pipe can be replaced in between of failure events. The results of the analyses show that about 9.5% of the pipes in the case study system is required to be replaced within the planning horizon. Analyses of the yearly pipe replacement requirements for the case study system are provided along with the compositions of the replacement. The effects of water main replacement policies, for which yearly replacement length scenario and yearly replacement budget scenario are used, during a planning horizon are simulated in terms of the predicted number of pipe failures and the saved repair costs.

• 동력기계공학회지
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• 제16권2호
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• pp.30-35
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• 2012

The geothermal energy is one of the renewable energy sources which can contribute in accomplishing a vision and goal of the national plan on energy for a government suggestion. Especially, the geothermal energy is evaluated as the nearly unlimited resources. The yearly underground temperature distribution by depth is very important to the design of air-conditioning system which uses a geothermal energy. Furthermore, there has no data for comparisons to numerical analysis. In this study, the yearly underground temperature is measured under the depth of 2 m in Tongyeong, and these data are compared with numerical analysis results for checking the accuracy. The results showed that the experimental temperature and numerical results had a good agreements and these results will be utilized to predict a performance of air-conditioning system for using a geothermal energy.