• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2007.02a
• /
• pp.3-8
• /
• 2007

최근, 실감 영상에 대한 관심과 요구가 증가하면서 신개념 서비스인 3차원 다시점(Multi-view) 방송에 대한 연구가 다양하게 진행되고 있다. 이와 더불어 광고와 게시를 목적으로 입체 영상과 입체 디스플레이 장치의 수요가 증가하고 있어, 앞으로 다시점 영상 콘텐츠와 디스플레이 장치가 활발하게 보급될 전망이다. 다시점 영상 콘텐츠는 제작 단계에서 컴퓨터 그래픽스 객체를 합성하면 보다 목적에 부합하는 콘텐츠를 제작할 수 있다. 본 논문에서는 다시점 카메라로부터 얻은 RGB 텍스쳐 데이터와 깊이 테이터에 컴퓨터 그래픽스 객체를 합성하여 다시점 합성 영상을 생성하는 방법을 제안한다. 또한, 제작된 다시점 합성 영상을 검증하고 재생하는 다시점 비디오 뷰어를 설계, 구현 한다. 가상의 다시점 영상에 그래픽스 객체를 합성하는 방법은 후 합성 기반으로, 임의의 그래픽스 객체 모델을 생성하여 깊이 정보를 부여하고, 가상 시점 영상의 생성과 동일한 방법으로 그래픽스 객체의 각 시점별 영상을 생성한다. 끝으로 깊이정보를 사용하여 가상 시점 영상의 적절한 좌표공간으로 그래픽스 객체를 삽입한다. 그래픽스 합성의 정확성 검증을 위해 다시점 그래픽스 합성 영상을 디스플레이하는 뷰어는 2D 및 입체를 모두 지원하고, view switching, frozen moment, view sweeping 등의 interactive special effect기법과 다양한 포맷의 저장이 가능하다. 또한, 입체 영상의 실험에서는 그래픽 객체의 입체감 조절을 위해 실제 카메라 시점 간에 필요한 중간시점영상의 개수를 결정할 수 있다.

• Korean Journal of Food Science and Technology
• /
• v.14 no.3
• /
• pp.265-270
• /
• 1982

An attempt was made to investigate the antioxidant activity of maltol, kojic acid, levulinic acid, furfural, 5-hydroxymethyl furfural (5-HMF), and pyrazine which had been known to be important intermediates of Maillard browning reactions. The activity of these compounds was determined by comparing induction periods of soybean oil substrates containing each compound at a 0.01M level with that of a control. The induction period was arbitrarily taken as the time in hours for a substrate to reach a peroxide value of 60meq/kg oil. The substrates and control were stored at $45.0{\pm}1.0^{\circ}C$ for 30 days. The induction periods of the control, kojic acid, furfural, 5-HMF, maltol, levulinic acid, and pyrazine were respectively 468, 592, 510, 498, 486, 450, and 402 hours. Kojic acid demonstrated considerable antioxidant activity, whereas furfural, 5-HMF, and maltol showed weak activivity. Pyrazine and levulinic acid showed pro-oxidant activity. Although the prooxidant activity of pyrazine seemed definite, that of levulinic acid appeared very weak.

• Korean Journal of Food Science and Technology
• /
• v.18 no.5
• /
• pp.389-392
• /
• 1986

To evaluate a pigment of the flower of cockscomb, Cclosia critata. as a natural food colorant, jelly-po, candy and sherbet were chosen as model foods and colorized to red with the pigment of the flower. Color changes were evaluated by analyses with Hunter color difference colorimeter. Lovibond tintometer and UV-visible spectrophotometer. Also sensory evaluation was carried out. The results obtained indicated that the red pigment of the flower had a good potential as food colorant, when it is utilized under the certain limited conditions: low water activity such as candy or low temperature. Data obtained indicated good correlation between instrumental analyses and sensory evaluation as well.

• The KIPS Transactions:PartC
• /
• v.14C no.3 s.113
• /
• pp.285-292
• /
• 2007

In the adaptable bandwidth allocation technique, a transmission plan for variable rate video data is made by the CBA algorithm and the data is transmitted by considering network traffic. But the CBA algorithm produces a transmission plan where the size of the increasing interval of transmission rate is generally larger than the size of the decreasing interval. And the transmission rate in CBA algorithm is changed in overflow curve during the increasing interval of transmission rate. This ぉy cause many frames to be discarded when available transmission rate is small. In this paper, a smoothing algorithm is proposed, where transmission rate is changed in the middle of underflow curve and overflow curve, but the transmission rate increases at the minimum. In order to show the performance, the proposed algorithm and a CBA algorithm were applied to a transmission plan in the adaptable bandwidth allocation technique, and the minimum frame rates, the average frame rates, the variation of frame rates, and the numbers of discarded frames were compared in both algorithms.

• Journal of the Korean Institute of Gas
• /
• v.13 no.4
• /
• pp.46-52
• /
• 2009

Hydrogen can extend the lean misfire limit to a large extent when it is mixed with conventional fuels for an internal combustion engine. This study is about fuel reforming to produce hydrogen enriched gas as a fuel for engine. Especially gasoline, which consists of numerous hydrocarbon fuels, considered as source of reformed gas. Various hydrocarbons, including commercial fuel were reformed and potentialities of reformed gas on vehicles were accessed. The reforming efficiency and hydrogen yield were observed. Maximum hydrogen yield were found with different gas hourly space velocity(GHSV) and O2/C ratio of reforming conditions.

• Journal of the Korean Institute of Gas
• /
• v.22 no.4
• /
• pp.1-6
• /
• 2018

An LNG bunkering system stores LNG in a horizontal IMO's C-Type tank insulated with perlite powder, and $10^{-2}$ Torr vacuum in the annular space between the double walls. Current storage tanks have high heat leakage, evaporating over 2.0% daily. A more efficiently insulated storage tank reducing the evaporation rate is required to develope. This research carried out thermal analysis on a new effective insulation method, i.e. double shield insulation system, that separates high super vacuum in the annular space between two tanks with a perlite vacuum in the back side of outer tank. This highly efficient insulation system obtained an evaporation rate of 0.16% per day under a $10^{-4}$ Torr vacuum. Even if the space loses its vacuum, the new insulation system showed a lower evaporation rate of 5.23% than the present perlite system of 4.9%.

• The Journal of the Korea Contents Association
• /
• v.18 no.3
• /
• pp.34-40
• /
• 2018

In this study, the optimal buffer size is calculated for seamless video playback on a mobile device. Buffer means the memory space for multimedia packet which arrives in mobile device for video play such as VOD service. If the buffer size is too large, latency time before video playback can be longer. However, if it is too short, playback service can be paused because of shortage of packets arrived. Hence, the optimal buffer size insures QoS of video playback on mobile devices. We model the process of buffering into a discret-time queueing model. Mean busy period length and mean waiting time of Geo/G/1 queue with N-policy is analyzed. After then, we uses the main performance measures to present numerical examples to decide the optimal buffer size on mobile devices. Our results enhance the user satisfaction by insuring the seamless playback and minimizing the initial delay time in VOD streaming process.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.3
• /
• pp.41-48
• /
• 2017

Recently, there has been a lot of ongoing research regarding financial transactions and payments due to the emergence of financial technology (FinTech). Payments have been processed through cash and credit cards, and payment methods have been simplified and are more convenient, with mobile payment via mobile cards and mobile phones. This study offers a new mobile payment method by using a mobile phone instead of a card reader or terminal. For payments, authentication is processed with the user's biometrics and a built-in fingerprint scanner, and the payment is processed after receiving an authentication code issued by the authorizing institution to confirm the user's identity. User biometrics and payment information is secured from any kind of malicious hacker by saving it in a Fast Identity Online (FIDO) Trusted Execution Environment (TEE) section in a smartphone. Regarding key security, every key is securely created in the FIDO TEE section, providing secure mobile payment by neutralizing various malicious attacks, including sniffing and the man-in-the middle attack.

• The KIPS Transactions:PartA
• /
• v.18A no.6
• /
• pp.249-254
• /
• 2011

This paper describes an efficient design of the interpolation circuit to generate the luma and chroma sub-pixels for H.264 motion estimation. The circuit based on the proposed architecture does not require any input data buffering and processes the horizontal, vertical and diagonal sub-pixel interpolations in parallel. The performance of the circuit is further improved by simultaneously processing the 1/2-pixel and 1/4-pixel interpolations for luma components and the 1/8-pixel interpolations for chroma components. In order to reduce the circuit size, we store the intermediate data required to process all the interpolations in parallel in the internal SRAM's instead of registers. We described the proposed circuit at register transfer level and verified its operation on FPGA board. We also synthesized the gate-level circuit using 130nm CMOS standard cell library. It consists of 20,674 gates and has the maximum operating frequency of 244MHz. The total number of SPSRAM bits used in our circuit is 3,232. The size of our circuit (including logic gates and SRAM's) is smaller than others and the performance is still comparable to them.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2008.05a
• /
• pp.334-349
• /
• 2008

댐에는 하류 홍수피해 경감을 위한 방류설비와 댐에 저장된 물을 생활 농업 공업용수로 활용하기 위한 취수설비가 구축되어 있다. 취수설비는 고객의 요구에 부응하기 위해 여러 종류의 개선사례와 형식변경을 통해 날로 발전을 거듭하고 있다. 1970년대 소양강댐이 건설된 후 1990년대 중반까지는 수력발전을 목적으로 수차발전기 분해점검을 위한 수리용 게이트가 채택되어 저수지 중층부에 설치한 사례가 많다. 경제부흥 초창기 우리나라가 해외차관으로 건설한 소양강댐, 안동댐, 대청댐 등의 취수설비가 이에 해당한다. 이후 1990년대 말까지 하류 농작물 냉해방지를 위해 상온수의 물을 취수하는 표면취수설비가 임하댐, 주암댐, 용담댐 등에서 채택 운영되고 있다. 그러다가 횡성댐, 장흥댐 등이 건설되는 2000년대 초부터 기존의 냉해방지와 조류 등 환경변화에 대처가 가능하도록 저수지 전 구간을 수심별로 구분 선택하여 취수하는 다공식 취수설비와 표면취수설비가 동시에 설치되는 복식형 취수설비가 채택 운영됨에 따라 단순 수리용 게이트에서 복합적인 기능을 갖춘 취수설비로 발전을 하였다. 2002년 태풍 '루사'와 2003년 태풍 '매미'로 인해 유입된 고탁도수가 장기간 댐 내에 체류하여 하류용수공급에 심각한 문제점이 발생되고, 부영양화로 인한 적조현상 등이 사회적으로 크게 이슈화됨에 따라 임하댐과 용담댐에서는 표면취수설비를 중간구간 취수가 가능한 분리형 선택취수설비로 개선한 결과(임하댐(2006), 용담댐(2008)) 댐 본래의 순기능인 청정수 담수가 가능해졌을 뿐만 아니라, 하류생태계 보존에도 크게 이바지하였다. 또한, 최근에는 전 구간 선택취수가 가능하도록 화북댐에는 정류판형 선택취수설비, 부항댐 및 성덕댐에는 실린더 게이트가 국내 최초로 도입되는 전환기를 맞이하게 되었다.