C2N2H10ㆍCr2O7의 결정구조 연구

고기영,남궁해,박상수 국민대학교 2001 기초과학연구소 논문집 Vol.20 No.-

비등방성 확산 필터와 형태학적 처리를 이용한 역하프토닝

고기영,주동현,염동훈,김두영 동아대학교 정보기술연구소 2001 情報通信硏究所論文誌 Vol.8 No.2

Digital Halftoning convert a continuous-tone images to a binary images. Inverse halftoning addresses the problem of recovering a continuous image from a halftoned binary image. Simple low pass filtering can remove the high frequency noise but it also removes the edge information. Thus the edge information should be separated from the halftoning noise. As a result, the edge of result image is blurring. This paper present that we obtain continuous-tone-image which using Anisotropic diffusion filter. To reduce noise without blurring the edges of reconstructed image use edge map. The experimental result show that proposed method gives a higher PSNR and better subjective quality than conventional methods. As a result, the edge information of reconstructed image reduce blurring.

시정수 비교기를 이용한 작은 크기의 위상고정루프

고기영,최영식,Ko, Gi-Yeong,Choi, Young-Shig 한국정보통신학회 2017 한국정보통신학회논문지 Vol.21 No.11

A novel structure of phase locked loop (PLL) with a time constant comparator and a current compensator has been proposed. The proposed PLL uses small capacitors which are impossible for stable operation in a conventional PLL. It is small enough to be integrated into a single chip. The time constant comparator detects the loop filter output voltage variations using signals which are passed through small and large RC time constants. The signal from the large RC time constant node is the average of the loop filter output voltage. The output voltage of another node is approximately equal to the present loop filter voltage. The output of the time constant comparator controls a current compensator and charge/discharge small size loop filter capacitors. It makes the proposed PLL operate stably. It has been simulated and proved by HSPICE in a CMOS $0.18{\mu}m$ 1.8V process.

Early-late 감지기를 사용한 고속 단일 커패시터 루프필터 위상고정루프

고기영,최영식,Ko, Ki-Yeong,Choi, Yong-Shig 한국정보통신학회 2017 한국정보통신학회논문지 Vol.21 No.2

A novel structure of phase locked loop (PLL) which has small size and fast locking time with Early-late detector, Duty-rate modulator, and Lock status indicator (LSI) is proposed in this paper. The area of loop filter usually occupying the larger portion of the chip is minimized using a single small capacitor. While the conventional PLL with a single capacitor loop filter cannot work stably, the proposed PLL with two charge pumps works stably because the output voltage waveform of the proposed a single capacitor loop filter is the same as the output voltage waveform of the conventional 2nd-order loop filter. The two charge pumps are controlled by the Early-late detector which detects early-late status of UP and DN signals, and Duty-rate modulator which generates a steady duty-rate signal. Fast locking time is achieved using LSI. It has been simulated and proved by HSPICE in a CMOS $0.18{\mu}m$ 1.8V process.

매몰형 포트 카테터의 담도스텐트 내부 설치술: 개에서의 실험적 연구

고기영,이임식,최원찬 대한영상의학회 2004 대한영상의학회지 Vol.50 No.4

Purpose: To investigate the feasibility of port catheter placement following a biliary stent placement. Materials and Methods: We employed 14 mongrel dogs as test subject. and after the puncture of their gall bladders using sonographic guidance, a 10-mm in diameter metallic stent was placed at the common duct. In 12 dogs, a 6.3 F port catheter was placed into the duodenum through the common duct and a port was secured at the subcutaneous space following stent placement. As a control group, an 8.5 F drain tube was placed into the gallbladder without port catheter placement in the remaining two dogs. Irrigation of the bile duct was performed every week by injection of saline into the port, and the port catheter was replaced three weeks later in two dogs. Information relating to the success of the procedure, complications and the five-week follow-up cholangiographic findings were obtained. Results: Placement of a biliary stent and a port catheter was technically successful in 13 (93%) dogs, while stent migration (n=3), gallbladder rupture (n=1) and death (n=5) due to subcutaneous abscess and peritonitis also occurred. The follow-up was achieved in eight dogs (seven dogs with a port catheter placement and one dog with a drain tube placement). Irrigation of the bile duct and port catheter replacement were successfully achieved without any complications. Cholangiograms obtained five weeks after stent placement showed diffuse biliary dilation with granulation tissue formation. However, focal biliary stricture was seen in one dog with stent placement alone. Conclusion: Placement of a port catheter following biliary stent placement seems to be feasible. However, further investigation is necessary to reduce the current complications. 목적: 금속 스텐트를 삽입한 담도에 포트 카테터를 삽입하는 것의 시술 가능성을 알아보고자 하였다. 대상과 방법: 잡견 14마리를 대상으로 초음파 유도하에 담낭을 천자한 후 유도철사를 총담관으 로 진입시켜 직경 10 mm의 담도 스텐트를 설치하였다. 스텐트 설치 후 12마리에서는 6.3 F 포트 카테터를 십이지장까지 삽입한 후 포트는 피하에 이식하였고, 나머지 두마리는 대조군으 로서 담도 스텐트 삽입 후 포트 카테터의 삽입없이 담즙의 유출을 예방하기 위해 담낭에 8.5 F 배액관을 설치하였다. 포트 카테터를 삽입한 개에서는 1주일 간격으로 포트를 천자하여 담 도를 세척하였고, 그 중 2마리는 3주후 포트 카테터를 교체하였다. 시술 성공율, 추적기간 동 안의 합병증, 담도 조영 소견 등을 분석하였다. 결과: 스텐트와 포트 카테터의 설치는 13예(93%) 에서 성공하였다. 합병증으로 십이지장으로 의 스텐트 이동(n=3), 담낭 파열(n=1), 피하농양, 복막염 등으로 인한 사망(n=5) 등이 발생 하였다. 5주간의 추적이 8예(포트 카테터를 삽입한 7예, 담낭 배액관을 삽입한 1예)에서 가능 하였으며 포트 천자를 통한 담도 세척과 포트 카테터의 교체는 합병증없이 가능하였다. 추적 담도 조영술상 모든 예에서 전반적인 담도 확장과 스텐트 삽입 부위의 미만성 육아조직 증식 소견이 보였지만 국소적인 담도 협착 소견은 담도 스텐트만 삽입하였던 1예에서 관찰되었다. 결론: 금속 스텐트를 삽입한 담도에 포트 카테터를 삽입하여 포트를 통해 담도를 세척하는 것 은 가능하였다. 임상에 적용하기에 앞서 합병증을 감소시키기 위한 연구가 좀 더 필요할 것으 로 생각된다

ThinkQuest Korea : 인터넷과 교육의 만남

고기영 한국스쿨넷학회 2000 학술발표 논문집 Vol.2000 No.1

Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II)의 결정구조

고기영,남궁해,한상곤,Go, Gi-Yeong,Nam, Gung-Hae,Han, Sang-Gon 한국결정학회 1998 韓國結晶學會誌 Vol.9 No.1

Bis(ethylenediamine)palladium(II)-Bis(oxalato)palladate(II0, (Pd(C2H8N2)2.Pd(C2O4)2)의 단위 착이온 및 결정의 구조들을 x-선 회절법으로 연구하였다. 이 결정은 단사정계이고, 공간군은 P21/c(군 번호=14)이다. 단위세포는 a=6.959(2), b=13.506(2), c=15.339(2) Å, β=99.94(3)이며, V=1420 Å3, Fw=509.04 Dc=2.380 gcm-3, F(000)=992, μ=25.46 cm-1 Z=4이다. 회절반점들의 세기는 흑연 단색화 장치가 있는 자동 4축 회절기로 얻었으며 Mo-KαX-선 (λ=0.7107 Å)을 사용하였다. 구조분석은 중금속법으로 풀었으며, 최소자승법으로 정밀화하였고, 최종 신뢰도 값들은 1472개의 회절반점에 대하여 R=0.021, Rw=0.030, Rall=0.032 및 S=2.10이었다. 착음이온들은 근본적인 평면구조로써, 이들의 충진구조는 a-축을 따라서 면간거리가 3.41Å인 이중체가 3.44Å 간격으로 배열되어있다.

언어적 측면에서 고찰한 디자인과 음악의 상호관련성에 관한 고찰

고기영 이화여자대학교 대학원 1988 硏究論叢 Vol.16 No.-

일본인 한국어 학습자의 조사 ‘을/를’, ‘이/가’ 교체 연구 - ‘-고 싶다’ 구문을 대상으로 -

고기영,박선희 한국언어과학회 2020 언어과학 Vol.27 No.1

LMS 적응 필터링 알고리즘과 에지맵을 이용한 역하프토닝

고기영,김두영 동아대학교 생산기술연구소 1999 生産技術硏究所硏究論文集 Vol.4 No.1

Digital Halftoning convert a continuous-tone images to a binary images. There are many good methods for digital halftoning: ordered dither, error diffusion and more recently direct binary search(DBS). Inverse halftoning addresses the problem of recovering a continuous image from a halftoned binary image. Simple low pass filtering can remove the high frequency noise but it also removes the edge information. Thus the edge information should be separated from the halftoning noise. As a result, the edge of result image is blurring. The 512×512 continuous tone Lenna image is halftoned by using clustered-dot ordered dithering, dispersed-dot ordered dithering, error diffusion method. This paper present that we obtain continuous-tone-image which using LMS adaptive filtering algorithm. This image discover the optimal filter weights. To reduce noise without blurring the edges of reconstructed image use edge map. Simulation results show that proposed method gives a higher PSNR and better subjective quality than conventional methods. As a result, the edge information of reconstructed image reduce blurring.