• 제목/요약/키워드: OCT

검색결과 1,422건 처리시간 0.03초

벌선의 항해학적 고찰 (A Study on the Navigation of Fishing Raft)

  • 정공흔
    • 한국항해학회지
    • /
    • 제10권2호
    • /
    • pp.1-10
    • /
    • 1986
  • For the purpose of estimation of navigational method and ability about fishing raft, we have practical navigation of her from Chujado on Oct, 7 to Maryang-ri , Kangjin-kun, Jeonranman-do on Oct.10. The results obtained are as follow : 1. Ancient navigation of her is thought to over to an isolated island in the vicinity with a good informations and experiences. 2. Speed of her in outward voyage is 1.34 knots, but is varied with structure and shape of her and ability of fishing raftman. 3. The lee way(U) of her with sail of hight 2.5m and breadth about 1.2m according to windspeed(W) is U=$0.038{\times}W$ 4. We could estimate to take only three days to go over from Chujado to Maryang-ri, Kangjin-kun. Jeonranam-do by her with sail, and make a voyage total 55 miles for thirty-four hours and ten minutes i, e, mean speed is 1.6knots resulty.

  • PDF

컴퓨터 시뮬레이션에 의한 일렉트렛트 센서의 최적 전계 해석과 응용 (A Study of Optimum Electromagnetic Field Analysis and Application of the Electret Sensor Using Computer Simulation)

  • 정동회;김상걸;김성렬;김용주;김영천;이준웅
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
    • /
    • pp.435-438
    • /
    • 1998
  • In this paper, Electret is formed to range voltage -5[kV] to -8[kV] by corona charging in PTFE film and sensor is manufactured by method of moments in sensing infra sonic. Charges of charged film are calculated also TSC measurement and induced potential of sensing electrode according to the charges is become aware of computer simulation. Electret Infra Sonic Transducer, which is designed and manufactured according to the potential and electric field simulation in using method of moments, is proved as it is effectively. Because sensitivity that measured under 10[Hz] is that average value of sensitivity rising rate is 6.34 [dB/oct] as average value is $\pm$1 [dB/oct] range -5[kV] to -8[kV] in corona charging film. As a result, it is believed that characteristic of acquired transducer can be application of medical treatment, industry, and animal life researches and the study of noise elimination, what's more, is required.

  • PDF

Synthesis and Antibacterial Activity of Novel [3-(4-substitutedphenylamino)-8-azabicyclo [3.2.1] oct-8yl]-phenyl-methanone Derivatives

  • Reddy, B. Surendra;Reddy, A. Babul;Reddy, G. Ramachandra;Reddy, P. Raveendra
    • 대한화학회지
    • /
    • 제55권6호
    • /
    • pp.969-973
    • /
    • 2011
  • The synthesis, as well as spectroscopic and biological studies of a novel class of [3-(4-substitutedphenylamino)-8-azabicyclo [3.2.1] oct-8yl]-phenyl-methanone derivatives are described. All the synthesized compounds were characterized by elemental analysis FTIR, $^1H$-NMR, $^{13}C$ NMR, and Mass spectral data. All the synthesized compounds were exhibit in vitro antibacterial activity.

Wavelength-Swept Cascaded Raman Fiber Laser around 1300 nm for OCT Imaging

  • Lee, Hyung-Seok;Lee, Hwi Don;Jeong, Myung-Yung;Kim, Chang-Seok
    • Journal of the Optical Society of Korea
    • /
    • 제19권2호
    • /
    • pp.154-158
    • /
    • 2015
  • We experimentally demonstrated a novel wavelength-swept laser using a cascaded Raman gain around 1310 nm. A 1064/1310 wavelength division multiplexing (WDM) coupler and coupled fiber Bragg gratings mirrors at 1064, 1117, 1175, 1240 nm are effectively used to increase the power efficiency in a laser ring cavity with highly non-linear fiber (HNLF) of 2 km. Linear wavelength sweeping is demonstrated with the 100 Hz triangular driving signal to fiber Fabry-Perot tunable filter (FFP-TF) around the 1310 nm region. The measured sweeping range and output power were 27 nm and 2.1 mW, respectively, which are suitable for optical coherence tomography (OCT) imaging.

한국어 단모음의 성별, 연령별 특징변화 및 인식 (Changes in Features of Korean Vowels with Age and Sex of Speakers and Their Recognition)

  • 이용주;김경태;차균현
    • 대한전자공학회논문지
    • /
    • 제25권12호
    • /
    • pp.1503-1512
    • /
    • 1988
  • As the basic analysis to solve the within-and cross-speaker variability in phoneme based speech recognition, changes in pitch and formant frequencies of 8 Korean vowels with age and sex of speaker has been investigated by analyzing a large number fo samples. Conclusions obtained are as follows: 1) Changes in pitch frequency with age and sex of speaker for children are hard to distinguish and the difference of before and after the voice change is analyzed approximately 0.2 oct. for female an 0.9 oct. for male. 2) While most of the formants of vowel considerably change with the age of speaker, the change becomes smaller as the age becomes older. 3) While there is an indirect correlation between pitch and formant with change in age, it is hard to see a direct correlation. 4) When the objects of the recognition experiment by pitch and formants are various speakers in each age and sex, pitch also works as an efficient recognition parameter.

  • PDF

루프 미러로 구성된 기준팔을 가지는 파장 스위핑 OCT 구현 (Realization of Swept Source Optical Coherence Tomography with Loop Mirror Reference Arm)

  • 김훈섭;남궁명우;이정렬;엄진섭
    • 산업기술연구
    • /
    • 제27권B호
    • /
    • pp.121-123
    • /
    • 2007
  • As a reflector of reference arm in OCT systems, a coated fiber reflector has mostly used. Instead, this paper has realized the swaept source optical coherence tomography system using a loop mirror within a reference arm. Through the experiments for a tilted thin glass plate, we found that the loop mirror is better than the coated fiber typed mirror for obtaining the clear image.

  • PDF

OCT 기반 H.264 transcoder를 위한 half-pixel 보정 기법 (Half-Pixel Correction for H.264 Transcoding in the OCT domain)

  • 권순영;임성렬;정기동
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
    • /
    • pp.364-366
    • /
    • 2005
  • 최신 동영상 압축 표준인 H.264는 압축 효율을 높이기 위해 기존의 표준과는 다른 1/2 화소 생성 방법을 사용한다. 그러므로 기존의 동영상 압축표준으로 압축된 비트열을 DCT 상에서 H.264로 트랜스코딩(transcoding)하기 위해서는 추가적인 보정 작업이 필요하다. 본 논문에서는 MPEG-2로 압축된 비트열을 DCT 상에서 H.264로 트랜스코딩 할 때 두 표준 간 1/2 화소 값의 차이를 보정하는 기법을 제안한다. 제안된 1/2 화소 보정 기법에서는 DCT 상태의 창조 프레임을 이용하여 두 표준 간의 차이 값을 구하여 입력으로 들어온 블록의 값에 더하여 보정한다. 픽셀 기반에서 보정하는 기법과 성능을 비교한 결과 제안하는 기법이 화질 면에서 우수하며 움직임이 빠른 비디오의 경우 계산량이 높아지는 것으로 나타났다.

  • PDF

SNR 향상을 위한 OCT topology의 설계 (Optical coherence tomography topology design for SNR improvment)

  • 박양하;정태호;오상기;김요희
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.212-214
    • /
    • 2002
  • Basically, OCT use the interference effect of Michelson interferometer. The receiver noise of interferometer is a important fact to improve the system performance. To improve the system performance for high resolution image processing, we design a interferometer topology adding the attenuator to the reference arm. In this paper, we design the receiver noise parameter and computer simulation. In this results, SNR of the new topology system is improved 5dB compare to standard interferometer.

  • PDF

전산기에 의한 Ready-Mixed Concrete의 품질관리를 위한 배합계산법

  • 김길주
    • 레미콘
    • /
    • 3호통권7호
    • /
    • pp.33-44
    • /
    • 1986
  • 본고는 일본「Concrete공학 」(Vol.20,No.10. Oct 1982)에 발표된 아부도산, 후등화이, 최도홍의 "전산기에 의한 레미콘의 품질관리를 위한 배합계산법"를 토대로 하여, 건설재료연구회의 "레미콘의 제조와 품질관리"를 참고로 한 것이다.

  • PDF