• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.203-208
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• 2012

Field experiment was carried out to identify the proper water exchange interval for the rice cultivation on reclaimed saline soil with different nitrogen levels in southwestern area. The nitrogen fertilizer was applied 14, 17 and 20 kg per 10a by ingredient, and intervals of water exchange treated 3, 6 and 9-day periods from transplanting of rice(Oryza sativa var. Cheongho) to maturing stage in Munpo soil series. The salinity levels ranged 0.10~0.24% and 0.24~0.32% of 3-day and 6-day respectively, whileas it ranged 0.35~0.52% for 9-day interval of water exchange during vegetative stage. Water exchange and nitrogen level showed significant effects on the plant growth, yield, and quality. The yield of milled rice on 3-day and 6-day interval of water exchange showed 497 kg/10a and 492 kg/10a and that were significantly higher than that of 9-day interval in 2008 and 2009. Milled rice yield of 9-day interval of water exchange was lower than that of 3-day and 6-day interval of all nitrogen levels. Plant growth and yield components were not significantly different between 3-day and 6-day interval of water exchange of all nitrogen levels. The combination of nitrogen fertilizer level of 17 kg/10a and 6-day interval of water exchange after transplanting might be recommended for maximum yield realization and minimize salt injury at reclaimed medium saline soil in southwestern area.

• The Korean Journal of Financial Management
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• v.23 no.1
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• pp.49-67
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• 2006

This study examines whether won/dollar futures have price discovery function and volatility spillover effect or not, using intraday won/dollar futures prices, volumes, and spot rates for the interval from March 2, 2005 through May 30, 2005. Futures prices and spot rates are non-stationary, but there is the cointegration relationship between two time series. Futures returns, spot returns, and volumes are stationary. Asymmetric effects on volatility in futures returns and spot returns does not exist. Analytical results of mean equations of the BGARCH-EC (bivariate GARCH-error correction) model show that the increase of futures returns raise spot returns after 5 minutes, which implies that futures returns lead spot returns and won/dollar futures have price discovery function. In addition, the long-run equilibrium relationship between the two returns could help forecast spot returns. Analytical results of variance equations indicate that short-run innovations in the futures market positively affect the conditional variances of spot returns, that is, there is the volatility spillover effect in the won/dollar futures market. A dummy variable of volumes does not have an effect on two returns but influences significantly on two conditional variances.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1324-1329
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• 2001

The depression of the external situation like the departure of WTO system and the plan of EEZ proclaim is forcing fishery into improving their fishing condition. By this international and domestic circumstance, development of the sea water cooling apparatus for fish hold storage is demanded sincerely. This study represents the thermal characteristics of the fish hold storage during transportation. The numerical analysis in this study is the finite volume method with the SIMPLE computational algorithm to study the seawater flow behavior in the fish hold storage. The computation were carried out with the variations of the circulating flow velocity and depth of fish hold storage. As the result of the three dimensional simulations, the mean temperature doesn't almost change by the circulating flow rate. find the mean temperature is suddenly changed by the ratio of depth of fish hold storage.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.10 no.1
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• pp.108-117
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• 1998

This study was performed to analyze the fluid flow characteristics and the temperature distribution of the aquarium for fish breeding. In this study, the finite volume method and turbulence k-$\varepsilon$ model with the SIMPLE computational algorithm are used to study the water flow in the aquarium. The calculation parameters are the circulating flow rate and the basin depth, and the experiments were carried out for the water flow visualization This numerical analysis gives reasonable velocity distributions in good agreement with the experimental data. As the results of the three dimmentional simulations, the sectional mean velocity increased as the sectional mean temperature increases for constant basin depth, and the mean velocity increased more rapidly for small basin depth than that of large basin depth, The mean velocity and temperature can be expressed as the function of the circulating flow rates and the basin depth.

• Journal of the Korean Data and Information Science Society
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• v.22 no.3
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• pp.467-476
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• 2011

We developed the hybrid model coupled with predictive model and business rule model for administration of injury by utilizing medical data of the National Health Insurance in Korea. We performed decision tree analysis using data mining methodology and used SAS Enterprise Miner 4.1. We also investigated under several business rule for benefits (expense paid by insurer) and claims of injury in National Health Insurance Corporation. We can see that the proposed hybrid model provides a quite efficient plausible results.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.5
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• pp.716-720
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• 2023

This study was designed to analyze the effects of reducing water turnover in olive flounder Paralichthys olivaceus farms, focusing on olive flounder growth, decreasing electricity costs, and developing measures to ensure business stability. Daily water turnover was set at 18 in the control group and six in the experimental group. Juvenile fish were reared for 12 months. No significant differences in mean weight were observed between groups until five months. After five months, the mean weight of the control group grew significantly faster than that of the experimental group. Maintaining water turnovers leverl at six turnovers for the first five months after stocking juvenile fish and then increasing water turnover resulted in a 34.4% reduction in electricity costs compared to the control group. This approach presents a potential method to enhance the profitability of olive flounder farms and ensure stable productivity and profitability without sacrificing olive flounder growth.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.405-407
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• 1997

본 논문은 자동차 번호판 용도문자를 인식하개 위한 전처리 과정으로써 웨이브릿 변환을 적용한 연구에 관해 기술한다. 웨이브릿 변환에 의하여 여과된 고주파 대역의 영상은 수평방향, 수직방향, 대각선 방향의 윤관석 형태로 세 개의 대역에 존재하게 되는데, 대상영상이 고주파 대역의 에너지량이 적게 나타나는 반면에 저주파 대역의 에너지량은 크므로 용도문자의 인식 과정에서 저주파 대역 부분만을 이용하였다. 저주파 대역에서 $20{\times}20$크기의 영상을 추출하고 영상을 정규화 하여 오츠알고리즘을 통한 이치화 과정을 거친 다음 역전파 신경망으로 인식함으로써 기존의 단순축소 방법보다 향상된 결과를 실험을 통하여 확인할 수 있었다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.12
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• pp.10-19
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• 2008

Daylight responsive dimming systems are energy saving systems using available daylight. It is not popular to be adopted in buildings because of blocked daylight by shading systems. Therefore, both daylight responsive dimming systems and automated roller shading systems should be integrated. In this research, prediction process of yearly lighting energy savings is developed for application integrated systems in buildings, and then the process is applied to an example building. The predicted data which are yearly lighting energy savings using developed process in a building are useful as a part of feasibility study for determination of application of such integrated systems.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.727-730
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• 2001

본 논문에서는 동영상 데이터의 효율적인 압축과 전송을 위하여 이산 웨이블렛 변환(Discrete Wavelet Transform)과 H.263 부호화[1] 방법을 이용한 영상 부호화 방법을 제안하였다. 이 방법은 웨이블렛 변환을 이용하여 영상을 여러 개의 주파수 영역별로 나누고 각각의 주파수특성에 따라 다른 부호화 방식을 취하게 된다. 제안된 방법은 정보량이 가장 많고 원본의 영상에 가장 가깝게 보존되는 저주파 영역은 H.263 부호화 방식을 사용하고, 나머지 고주파 영역은 산술부호화 방식을 사용함으로서 각각의 주파수 특성을 적절하게 고려한 압축을 하여 그 효율을 증대시키게 된다. 또한 웨이블렛 변환에 따른 저주파 영역의 크기는 실제 영상 크기의 4분의 1이 되는데, 이러한 사실은 H.263 부호화에서 움직임정보의 검출 단위인 매크로블럭(macro-block)의 개수를 줄여 웨이블렛 알고리즘 사용에 드는 추가적인 부호화 시간을 보상하게 한다. 저주파 영역의 H.263 부호화 방식으로 인한 양자화 오류로 나타나는 역 웨이블렛 변환에서의 화질열화를 최소화하기 위해 2단계 웨이블렛 변환을 사용했는데 실험결과 1단계 웨이블렛 변환을 사용한 영상에 비하여 화질이 개선됨을 알 수 있다.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.192.2-193
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• 2003

기존 저온저장고의 가습방법을 개선하고 아울러 음이온을 농산물의 선도 유지에 이용하고자 아쿠아이온발생시스템의 설계, 제작이 레너드효과를 응용하여 이루어졌다. 시스템의 아쿠아음이온의 발생량은 42,965음이온/cc, 입자크기는 $10^3$$\mu\textrm{m}$ 이하, 가습속도는 0.13$\ell$/h이었으며 85% 이상의 고습도 조건에서도 결로가 발생하지 않는 상태로 가습이 가능하였다. 아쿠아이온 클러스터에 의해 저장고는 90% 이상의 균일한 고습도와 정온을 유지할 수가 있었다. 아쿠아이온시스템의 경우 유해가스와 분진등을 흡착, 제거하여 저장고 내를 청정하게 유지시키는 기능이 있는데, 에틸렌가스 제거 효과는 초기 농도 50ppm에서 5분후에 50% 이상이 제거되고 2시간 후에는 3ppm 이하로 제거되었다. 아쿠아이온발생시스템이 브로콜리, 잎상추, 애호박 등의 보관에 적용되었다. 아쿠아이온발생시스템이 부착된 저장고($0^{\circ}C$)에서 20일동안 보관한 경우 기존 저장고에 보관한 경우에 비하여 감모율, 부패율 및 관능적 품질에 있어서 유의적으로 우수한 차이를 나타내었다.