블록화 현상의 측정을 통한 영상의 화질평가

이상우,박상주,Lee, Sang-Woo,Park, Sang-Ju 한국정보처리학회 2008 정보처리학회논문지B Vol.15 No.5

Block based transform coding is most popular approach for image and video compression. However it suffers from severe quality degradation especially from blocking artifacts. The subjective quality degradation caused by such blocking artifacts in general does not agree well with an objecive quality measurement such as PSNR. Hence new quality evaluation technique is necessary. We propose a new image quality assessment method by measuring blocking artifacts for block based transform coded images. In order to characterize blocking artifacts, proposed method utilizes the facts that, blocking artifacts, when occur, have different pixel values along the block boundaries and such differences usually continuously span along the whole boundaries. This method does not require the original uncompressed image. It operates on single block boundary and quantifies the amount of blocking artifacts on it. Experiments on various compressed images various bitrates show that proposed quantitative measure of blocking artifacts matches well with the subjective quality of them judged by human visual system. 블록 기반의 변환 부호화 방식은 영상 압축 표준에 널리 사용되고 있다. 이러한 방식에서 발생하는 여러 종류의 화질 열화 현상 중 블록의 경계에서 나타나는 블록화 현상은 화질을 떨어뜨리는 대표적인 요인이다. 블록화 현상에 의한 화질 열화는 기존의 PSNR 같은 화질 측정값과 부합하지 않아 새로운 평가 기법의 개발이 필요하다. 본 논문은 블록 기반 변환 부호화 방식으로 압축된 영상에서 블록화 현상이 발생한 정도를 측정하여 화질을 평가하는 새로운 기법을 제안한다. 본 논문에서 제안하는 기법은, 블록화 현상이 블록 경계에서 발생하면 경계면에서 양쪽 화소의 밝기값의 차이가 나며, 대개 그 길이가 블록의 경계 길이 만큼 이어지는 특징을 이용하여 블록화 현상을 찾아낸다. 본 논문에서 제안하는 방법은 원본 영상이 필요치 않고, 블록 경계에서 동작하며, 블록화 현상의 발생 정도를 수치화 한다. 다양한 압축 영상에 본 기법을 적용한 결과, 제안하는 블록화 현상 평가 수치는 인간의 시각 특성에 기반한 주관적 화질 평가와 부합하는 것을 확인하였다.

원산지규정 분석을 통한 수출 중고품에 대한 FTA 특혜관세 활용방안

이상우,이춘수,Sang-Woo Lee,Chun-Su Lee 한국국제상학회 2015 國際商學 Vol.30 No.2

오늘날 무역거래의 대상은 대부분 신품인 경우가 많으나, 최근 물품의 내구성이 증대되 면서 중고차량, 중고기계 등 중고품의 무역거래량도 점차 늘어나고 있는 추세를 보이고 있 다. 이에 중고품에 대한 FTA 특혜관세 활용방안 및 법적 근거에 대한 검토가 필요하다. 그 러나 중고품의 경우 기존 FTA 협정에서 관련 규정이 거의 없기 때문에 중고품이 FTA 특혜 관세의 대상이 될 수 있는지의 여부, 중고품에 대한 원산지판정 방법 등의 문제를 논하는 데에 한계가 있다. 본 연구는 수출 중고품의 FTA 활용현황과 활용상의 문제점을 파악하고, FTA 협정문에 서 규정하고 있는 중고품 관련 원산지규정분석을 통해 중고품의 FTA 특혜관세활용방안을 모색하는데 연구목적을 두고 있다. 특히, 중고품관련 원산지규정 분석을 각 국가별 체결협정 대상으로 검토하기 위해서 중고품의 FTA 특혜관세 적용 가능성 파악을 위한 FTA 협정 상 관련 규정에 대한 검토, 원산지결정기준의 충족 여부에 대한 검토 그리고 신품의 원산지 지위의 중고품 승계문제를 다루고 중고품 수출시 특혜관세 활용방안을 위해 시스템구축 사례를 제시한다. The objective of this study is to grasp the FTA utilization status for used goods that are exported and the problems related to utilization, and to grope for a plan to utilize the FTA preferential tariffs by analyzing rules of origin specified in FTAs in relation to used goods. This study performed a literature review utilizing secondary sources and interview. For used goods, as there are almost no related provisions in the existing FTAs, there are limitations in discussing issues such as whether used goods can be an object of an FTA preferential tariff or not, and the method to determine the county of origin of used goods. Accordingly, cooperation from original manufactures is required for utilization of the FTA preferential tariff on used goods, and a plan to institutionalize such a part should be arranged. Also, rules of origin for used goods is required to be separately specified to allow easier application differently from that of new goods considering the present situation where utilization is practically difficult.

$Ar/N_2 및 Kr/N_2$혼합가스의 교류절연파괴 특성

이상우,김인식,이동인,이광식,김이국,Lee, Sang-Woo,Kim, In-Sik,Lee, Dong-In,Lee, Kwang-Sik,Kim, Lee-Kook 대한전기학회 2001 전기학회논문지C Vol.50 No.12

In this paper, the ac breakdown characteristics of pure Ar, Kr and $N_2$ gas with gas pressure range of 58.8-137.3[kPa] under uniform and non-uniform fields were investigated, and the measured values were compared with those In Ar/$N_2$ and Kr/$N_2$ gas mixtures with pressure varying. Summarizing the experimental results, the breakdown voltages of Pure $N_2$gas, under uniform and non-uniform fields, were increased about 4.8 and 1.1 times than those of pure Ar gas, and about 4.4 and 1.2 times than those of pure Kr gas, and the ac breakdown voltage increased with the pressure increasing. The breakdown voltages of Ar/$N_2$ gas mixtures were decreased with decreasing the mixture ratio of Pure $N_2$ gas. In case of Ar(85%)/$N_2$ (15%) and Ar(70%)/$N_2$ (30%) gas mixtures comparing to the pure Ar gas, the breakdown voltages under uniform field were increased about 1.8 and 2.2 times, and under non-uniform field were increased about 1.1 and 1.3 times at the pressure of 101.3[kPa]. Also, in case of Kr(85%)/$N_2$ (15%) and Kr(70%)/$N_2$ (30%) gas mixtures comparing to the pure Kr gas, the breakdown voltages under uniform field were increased about 1.7 and 2.0 times, and under non-uniform field were increased about 1.0 and 1.2 times. Corona inception voltage of Kr(70%)/$N_2$(30%) gas mixtures under non-uniform fields were increased about 1.28 times than those of Ar(70%)/$N_2$ (30%) gas mixtures. In case of practical incandescent lamps, luminous and lifetime of Kr(70%)/$N_2$ (30%) gas mixtures were increased about 1.15 and 1.21 times than those of Ar(70%)/$N_2$ (30%) gas mixtures.

남북한 분단체제와 신상옥의 영화

이상우(Lee Sang-Woo) 한국어문학회 2010 語文學 Vol.0 No.110

This article examine the relation between Korea’s division system and the films of Shin Sang-ok, who was one of very famous Korean film directors in the golden age of Korean cinemas. Shin Sang-ok has been maybe the only Korean director, who produced his films in two Koreas. Before he was kidnapped by North Korean kidnap gangs, he was an outstanding film director in South Korea, who produced several popular films, as like 〈A Romance Papa〉, 〈King Yeonsan〉, 〈the evergreen tree〉, 〈a guest and mother)〉, 〈the Red muffler〉, and so on. Also, He managed the biggest film company ‘Shin Film’ and the biggest film studio ‘Anyang Film Studio’ in South Korea in 1960s, he maintained to good relation with the president Park Chung-hee’s government at that time. However, as Shin criticized the film policy of Park Chung-hee’s government, especially the problem of film censorship, the conflicts between them went to worse way in 1970’s. And then Shin was kidnapped with his ex-wife a famous Korean film actress Choi Eun-hee to North Korea. Shin abd Choi stayed in there during the 8 years and produced 7 films in North Korea’s Monolithic Ideal Logical System by Kim Jung-il’s enforcement and immense supports. At that time, Shin produced several remarkable films in North Korea, as like 〈not returned the emissary〉, 〈the salt〉, 〈a story of the escape〉. Finally, Shin and Choi escaped from North Korea for obtaining the freedom to the Western world. Two Koreas’s division system brought the restriction of creative film making to a film director Shin Sang-ok.

군 소화기 사격장 소음측정 및 소음저감 방안 평가

이상우,김희석,정상조,Lee, Sang-Woo,Kim, Hee-Seok,Jeong, Sang-Jo 한국군사과학기술학회 2009 한국군사과학기술학회지 Vol.12 No.1

Civil petitions and law suits against the military rifle shooting noise have been increased because many military shooting ranges are located near civilian residential area. In order to solve the noise problems, military have devised various methods. In this study, propagation properties of rifle shot through atmosphere were investigated. The military rifle shooting noise level at 5m from muzzle was between $l14{\sim}120dB$ in all directions. The noise level loom both backward and sideward away from system firing range consisting lines of 8 shooting locations were 90dB, when shots were all fired within 10 seconds. At present some of military bases established sound barriers, muzzle enclosures, silencers, and indoor shooting ranges to reduce noises and these prevention methods can reduce noise by $5{\sim}20dB,\;5{\sim}9dB,\;5{\sim}13dB,\;40{\sim}50dB$, respectively. Even though indoor shooting range has the best performance, it requires very expensive construction cost and has short length between target and shooter. In comparison, muzzle enclosure is cheap, but because it is installed in fixed position it can only be used in one shooting position. Therefore a commander should select appropriate methods to reduce military rifle shooting noise considering distance from residential area to the range, mission of military training, budget, etc.

ITU-T SG3

이상우,박혜진,전승화,이병남,강신원,박기식,Lee, Sang-U,Park, Hye-Jin,Jeon, Seung-Hwa,Lee, Byeong-Nam,Gang, Sin-Won,Park, Gi-Sik 한국정보통신기술협회 2005 TTA저널 Vol.101 No.-

중국증권시장의 정보이전효과에 관한 연구

이상우,이의경,Lee, Sang-Woo,Lee, Eui-Kyung 한국데이터정보과학회 2012 한국데이터정보과학회지 Vol.23 No.6

본 논문은 중국의 상해, 심천, 홍콩증권시장간의 정보이전효과를 연구한 것이다. 세 개의 중국 증권시장은 모두 미국의 증권시장수익률에 강하게 영향을 받는데 그 정도는 개방화가 제일 잘된 홍콩증권시장이 가장 크며 상해증권시장, 심천증권시장의 순으로 영향을 받는 것으로 나타나고 있다. 상해증권시장이나 심천증권시장은 서로 간에 수익률이전효과나 변동성전이효과가 존재하지 않지만 이 두 시장은 모두 홍콩증권시장수익률의 영향을 받는 것으로 나타났다. 하지만 미국증권시장의 움직임을 통제하면 이러한 효과는 사라지게 되어 중국의 증권시장간의 정보이전효과는 존재하지 않는 것으로 나타나고 있다. 이러한 결론은 중국의 세 개의 증권시장이 상호독립적인 성격이 강하다는 것을 의미하며, 중국의 증권시장 연구 시 시장 간의 독립성을 반영해야 할 것으로 생각된다. This study examines stock market co-movement among three China stock markets: Shanghai stock market, Shenzhen stock market, Hongkong stock market. US stock market leads three China stock markets and Honkong stock market leads Shanghai and Shenzhen stock market. But there are no lead-lag effects among China stock markets after controlling US stock market effect. These results could be important for the investors and firms that are interested in China stock markets.

소형 연료전지 연계형 DC GRID 부하 특성

이상우,이상철,권오성,배준형,박태준,강진규,이동하,Lee, Sang-Woo,Lee, Sang-Cheol,Kwon, O-Sung,Bae, Jun-Hyung,Park, Tae-Joon,Kang, Jin-Kyu,Lee, Dong-Ha 한국태양에너지학회 2012 한국태양에너지학회 논문집 Vol.32 No.suppl3

In recent years, understanding the dynamics of DC distribution system has become critically important due mainly to the increasing needs for the interconnection of DC distributed generators and the (DC-based) electric vehicle (EV) charging systems. In this paper, the characteristics of the DC grid system connected to the compact proton exchange membrane fuel cell (PEMFC) has been studied. In particular, the voltage and current transient phenomena were measured by varying the load of the DC grid system. Also, the voltage and current ripple were measured at the different load conditions. Our experimental results clearly manifested that the study contributes to the establishment of fundamental method to characterize the small DC grid system including distributed generation.

평행한 이중 슬롯과 Taper형 급전선로를 이용한 광대역, 고이득 마이크로스트립 안테나의 설계

이상우,이재성,김철수,Lee, Sang-Woo,Lee, Jae-Sung,Kim, Chol-Soo 한국전자파학회 2007 한국전자파학회논문지 Vol.18 No.3

본 논문은 IEEE 802.11a의 표준 규격$(5.15\sim5.25\;GHz,\;5.25\sim5.35\;GHz,\;5.725\sim5.825\;GHz)$을 하나로 통합할 수 있는 광대역, 고이득 안테나를 설계 및 제작하였다. 광대역 구현을 위해 사각 패치에 평행한 이중 슬롯을 삽입하였으며, 동축 프로브 급전 방식을 적용하여 슬롯에 의한 정전 성분을 상쇄시키고, $\lambda_g/4$ 임피던스 변환기를 Taper형 선로로 구성하여 광대역 임피던스 정합이 용이하게 하였다. 안테나의 이득을 개선하기 위하여 $2\times2$ 배열 구조로 최종 설계하였으며, 최종 제작한 안테나는 $5.01\sim5.95\;GHz(B/W\doteqdot940\;MHz)$ 대역에서 return loss -10 dB 이하의 양호한 반사 손실과 13 dBi 이상의 높은 이득을 얻을 수 있었다. In this paper, we have designed and fabricated a wide-band and high gain antenna which can integrate a standard of IEEE 802.1la$(5.15\sim5.25\;GHz,\;5.25\sim5.35\;GHz,\;5.725\sim5.825\;GHz)$. We inserted a parallel dual slot into a rectangular patch to have wide-band, and we offset an element of capacitance from the slot by using coaxial probe feeding method. We also designed a converter of $\lambda_g/4$ impedance with taper type line so that wide-band impedance can be matched easily. We finally designed structure with $2\times2$ array in order to improve the antenna gain, and the final fabricated antenna could have a good return loss(Return loss$\leq$-10 dB) and a high gain(over 13 dBi) at the range of $5.01\sim5.95\;GHz(B/W\doteqdot940\;MHz)$.

RF 스퍼터링법을 이용한 $LiNbO_3/Si$구조의 전기적 및 구조적 특성

이상우,김광호,이원종,Lee, Sang-Woo,Kim, Kwang-Ho,Lee, Won-Jong 한국전기전자재료학회 1998 전기전자재료학회논문지 Vol.11 No.2

The $LiNbO_3$ thin films were prepared directly on Si(100) substrates by conventional RF magnetron spurttering system for nonvolatile memory applications. RTA(Rapid Thermal Annealing) treatment was performed for as-deposited films in an oxygen atmosphere at 600 $^{\circ}C$ for 60 s. The rapid thermal annealed films were changed to poly-crystalline ferroelectric nature from amorphous of as-deposition. The resistivity of the ferroelectric $LiNbO_3$ film was increased from a typical value of $1{\sim}2{\times}10^8{\Omega}{\cdot}cm$ before the annealing to about $1{\times}10^{13}{\Omega}{\cdot}cm$ at 500 kV/cm and reduced the interface state density of the $LiNbO_3/Si$ (100) interface to about $1{\times}10^{11}/cm^2{\cdot}eV$. Ferroelectric hysteresis measurements using a Sawyer-Tower circuit yielded remanent polarization ($P_r$) and coercive field ($E_c$) values of about 1.2 ${\mu}C/cm^2$ and 120 kV/cm, respectively.