• Journal of the Institute of Convergence Signal Processing
• /
• v.10 no.3
• /
• pp.151-157
• /
• 2009

In this paper, we proposed an algorithm of redeye correction. For naturally redeye correction, we assumed positions of the redeye at an image which produced redeye, and we estimated rate of the redeye to apply the appropriate redeye correction suitably. We extract and label pixels those are possible of generating redeye using red, skin and reflected light color. The each labeled group is decided by rates of length and width, dimension, density, the color of white of the eye and reflected light color of groups for the redeye group. We corrected positions of redeye using blurring effect, naturally. In the case of designing the proposed algorithm, we designed the redeye correction hardware using the minimum of memories for efficiency of hardware.

• 프린팅코리아
• /
• v.12 no.9
• /
• pp.90-93
• /
• 2013

한국코닥은 불황을 이기는 대표 아이템으로 소노라 XP 무현상 판재를 추천한다. 코닥 소노라 XP 무현상 판재는 이름의 X에서 알 수 있듯이 No Processing, 즉 무현상 과정을 강조한다. 또한 자연 그대로의 상태를 보존하고 있는 북아메리카 사막 지명인 소노라(Sonora)를 이름으로 차용함으로써 환경친화적인 의미를 상징화하고 있다. 친환경적이면서도 가격을 뛰어넘는 가치를 창출함으로써 고객의 부가가치를 높여주고 고정비용을 낮춰주는 제품이라고 할 수 있다.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.37 no.7
• /
• pp.637-646
• /
• 2013

This study aims to numerically investigate the natural convection characteristics of a magnetic fluid in a cubic cavity. The governing equations of the magnetic fluid are solved using the Generalized-Simplified Marker and Cell Method (GSMAC). The natural convection and heat transfer characteristics of the magnetic fluid were analyzed by varying the intensity and direction of the magnetic field. As a result, it was found that the natural convection characteristics were controlled by the intensity and direction of the magnetic field, and the mean Nusselt numbers were minimized at a vertical intensity of H=-4000 and horizontal intensity of H=12000 of the magnetic field. In addition, the mean Nusselt numbers increased with the intensities of the magnetic field, regardless of the direction of the magnetic field.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.34 no.7
• /
• pp.721-727
• /
• 2010

The spontaneous ignition of coal stockpile causes serious safety and economic problems. Such spontaneous ignition occurs in coal stockpile when the rate of heat released by the oxidation of coal is greater than the rate of heat lost to the surroundings. In this study, a two-dimensional unsteady model is adopted for studying spontaneous ignition and the numerical results are compared with experimental results. The numerical results are in a good agreement with the experimental ones. Depending on the porosity, the internal maximum temperature, pressure, and oxygen mass fraction during spontaneous ignition are investigated. On the basis of the numerical results, the transient temperature variations for several shapes of coal stockpiles are analyzed. Further, the physical mechanisms of hot-spot formation and spontaneous ignition are analyzed.

• The Journal of the Korea Contents Association
• /
• v.6 no.5
• /
• pp.42-55
• /
• 2006

In most multimedia systems, the environment is considered as a passive background. In virtual environment simulating real world, however, terrain affects many events such as wind, rain, cloud. Therefore, it is necessary to model terrain and meteorological phenomenon in order to simulate realistic virtual environment. In those modeling, not only height and location information but also environmental factors such as temperature and humidity are important. An event is composed of many activities and subevents based on causality and consists of precondition , procedure and effects. Each part of an event is formulated in terms of a number of parameter variables, which correspond to its associated factors on existence or states of entities and relation. This paper represents terrain and environmental factor using contour map. Moreover, we define various events and their procedures in terms of causality in virtual environment.

• Journal of the Korean Magnetics Society
• /
• v.17 no.6
• /
• pp.253-258
• /
• 2007

In this study, an analysis of natural convection of magnetic fluids in a closed-semicircular pipe was performed by the numerical methods. For the numerical method GSMAC method of Siliomis is used. From the results of numerical methods it is verified that the natural convection of the magnetic fluid, I investigated the nature convection phenomenon of the magnetic fluid with numerical analysis and was going to study the thermodynamic characteristic of the magnetic fluid. Because the effect of magnetic field control natural convection, we needed to find effective method to eliminate heat in the cure of heat transfer.

• Proceedings of the Korea Contents Association Conference
• /
• 2003.05a
• /
• pp.132-138
• /
• 2003

The caustic effect provides some of the most amazing indirect illuminated light patterns or scenery one could find in nature. We can perceive this in forms of twinkling stars, shimmering, visually deflected spoon in the water and other various occasions. To generate the caustic effect more realistic and effectively in 3D animation the understanding of the caustic effect and its application is very crucial. However, thor exists various factors in creating the caustic effect other than two main factors discussed in this paper and these factors will require to be studied and tested. In this report, various cases, which used the caustic effect to create more realistic scenery are studied and the role of the caustic effect played in various sceneries are analyzed. In addition to these case studies it is also experimented with changes in different conditions On the basis of the result of case studies, the report demonstrates how the caustic effect can be used to create more realistic scenery by conducting substantiate experiment and research on practicing 3D animation. With all of these researches, the paper is to present the education guide to produce more realistic scenery in 3D animation.

• RED RIBBON
• /
• s.64
• /
• pp.34-35
• /
• 2005

• 한국방재학회:학술대회논문집
• /
• 2011.02a
• /
• pp.171-171
• /
• 2011

급격한 기상이변과 자연현상의 변화에 의해 자연재해가 발생하며, 이러한 변화로 인해 전 세계적으로 환경뿐만 아니라 방재의 중요성 또한 대두되고 있으나, 강우 강도의 예측 분야에서는 여유추정시간의 차이로 인해 방재현상에 대한 구체적인 협력을 하지 못했던 것이 사실이다. 현재 가장 많이 사용하고 있는 레이더 강우자료와 지상 우량계의 강우자료는 여유추정시간이 3시간에서 4시간 사이의 단기 예측만을 가능하게 한다. 본 연구에서는 이의 개선을 위하여 청미천 유역을 대상으로 GIS를 이용하여 CN value를 추출하고, 지역 강우 모형인 Weather Research Forecast(WRF) - Advanced Research WRF(ARW)를 통하여 모의한 강우자료에 대하여 과거 같은 기간의 강우자료와 비교 검증한 후 지역 강우 모형을 통하여 모의한 자료를 HEC-HMS의 Input자료로 활용하여 지역 유출량을 산정한다. 또한 유역의 지표면 유출 모의를 통하여 강우-유출현상과 수리-수문학적 과정을 상호 연결하고, 강우에 의한 유역 지표면에서의 유출을 도출하며, 최적화된 매개변수들의 조합을 개선하여 대상유역의 현상을 보다 유사하게 나타낼 것이다. 이와 함께 WRF-ARW 모형을 통하여 여유추정시간의 증가를 모색하며 그로인한 홍수예측 및 경계체계를 확립하기 위해 연구를 진행한다. 이 지역강우 모형의 대한민국 지형의 적용성 즉, 대한민국 지형에 가장 잘 어울리는 최적화된 매개변수들의 조합을 알아내고 그의 적용현실성을 찾아내려 한다. 더 나아가 강우에 대한 예측을 통해 홍수 경보 체계를 위한 자료로 활용할 수 있는 방안 또한 모색할 것이다.

• Proceedings of the KIPE Conference
• /
• 2016.07a
• /
• pp.385-386
• /
• 2016

직접 변조 방식(direct modulation)을 사용한 Modular Multilevel Converter(MMC)의 6개의 암 캐패시터 전압의 자연균형화(Natural Balancing) 현상은 여러 연구 및 실험에서 관측되고 있다. 또한, 이러한 현상의 원리뿐만 아니라, 시스템 파라미터와 밸런싱 동특성사이의 관계가 수학적인 분석을 통하여 검증되었다. 직접 변조 방식은 간접 변조 방식(indirect modulation)과 달리, 입/출력 AC 및 DC 측 제어기 외에 암 캐패시터 전압 밸런싱을 위한 순환전류 제어기가 존재하지 않지만, 캐패시터 맥동 저감을 위해 일반적으로 캐패시터 2 고조파 맥동 제어기를 필요로 한다. 본 논문에서는 이러한 직접 변조방식을 사용한 MMC의 2고조파 전압 맥동 제어기가 암 캐패시터 전압 자연 밸런싱에 미치는 영향을 고찰하고 분석한다. 또한, 2 고조파 전압 맥동 제어기의 유무에 따른 전압 자연 밸런싱의 동특성에 대한 비교를 400MW MMC full-scale 시뮬레이션을 통해 살펴보도록 한다.