NOTES ON REGULAR AND INVERTIBLE AUTOMATA

Park, Chin_Hong,Shim, Hong-Tae 한국전산응용수학회 2004 Journal of applied mathematics & informatics Vol.16 No.1

We shall discuss some properties of quasi-homomorphisms associated with automata. We shall give some characterizations in terms of characteristic semigroups for regular and invertible attomata.

고호모시스테인증과 동반된 소뇌출혈 1예

홍석찬,안재영,조수진,정진상,이광호,홍승철,변홍식 대한신경과학회 1999 대한신경과학회지 Vol.17 No.3

양안스크린 방법을 이용한 물체의 정확한 3D 좌표구현에 관한 연구

홍진수,이광훈 순천향대학교 기초과학연구소 1999 순천향자연과학연구 논문집 Vol.5 No.2

The human visual system(HVS) is based on the principle of binocular disparity. Stereoscope method is relatively simple to device a scheme with the principle. Also, the method has remarkable depth-cue, even though it is too hard to decide that exactly position of the object. So, the discussion of present study is focused on display of the body's position by supplementing imperfection of stereoscope still remaining even though the evolution of vector calculations and plan equations are introduced in addition to the method.

회절현상을 이용하여 나노크기의 임의 형상을 제작하는 새로운 방법

홍진수 순천향대학교 기초과학연구소 2003 순천향자연과학연구 논문집 Vol.9 No.1

For the nano-scale patterning of arbitrary shape the photolithography and ion beam fabrication methods are employed. When, in the photolithography, the electromagnetic waves such as UV and X-ray are incident on the mask patterned in nano-scale, the diffraction effect are occurred and degrades nano-patterning. A convex lens is well-known Fourier transformer even though the size of aperture is very large compared to the wavelength of electromagnetic wave. if the Fourier-transformed mask is placed at the front side of the lens, the nano-scale pattern is observed on the plane with some distance away from the lens. The new method presented here is not more excellent than photolithography and ion beam methods, but its setup is very simple. Here the feasibility study has been done theoretically in the field of Fourier optics, and, in the future, should be confirmed with proper experiments.

이동무선채널에서 1-비트 차동검파를 갖는 CPM의 성능 향상

陳年鋼,方成日,姜洪求 단국대학교 1993 論文集 Vol.27 No.-

In this paper, the performance of constant envelope digital CPM with 1-bit differential detection has been analyzed in time selective fading AWGN channels. The analysis is based upon the canonic receiver model combining postdetection for performance enhancement. In radio mobile communication channel with AWGN and fading, it is shown that the diversity receiver is effective in decreasing influence of the AWGN and the fading. Among the CPM schemes, the performance of 2SRC is found to be the best. The 3RC and GMSK(B_iT=0.25) performances are quite close and 2RC and 2SRC performances are quite close.

펄스 제동복사로 여기된 단수명 이성질체 측정

홍진수 순천향대학교 기초과학연구소 1995 순천향자연과학연구 논문집 Vol.1 No.2

펄스 제동복사 엑스선으로 핵자를 공명흡수시켜 ㎲ 수명(lifetime)을 갖는 이성질체(isomer)를 생성하였다. 이 이성질체가 천이할 때 발생되는 감마선을 CsF 섬광기(scintillator)/광증폭기(PMT)로 이루어진 검출기로 측정하였다. 측정을 가능케하기 위해 엑스선 펄스가 입사할 때 검출기는 활동하지 못하고, 펄스가 없을 때 검출기 작동되도록 외부 전압으로 조정하였다. CsF는 한 개의 섬광 원소만이 알려져 있고 이 원소는 ㎱ 시간반응을 나타내기 때문에 이 보다 긴 시간반응을 보이는 NaI(Tl)보다 더 빨리 작동한다. 그러므로 CsF는 핵에너지 레벨의 시간정보를 알고자하는 실험에서 유용하게 쓰인다. 근래에 CsF의 결점인 가시광선 거둠율(light yield)은 많이 향상되어 NAI(Tl)가 응용되는 거의 모든 분야에 사용되어진다. CsF/PMT 검출기로 이성질체에 대한 데이터를 얻는 방법이 논의되고, 176Hf, 181Ta, 81Br, 201Hg의 이성질체로부터 시간 분광을 얻어 최초상태의 공명흡수로부터 생성된 이성질체의 적분단면적을 찾았다. 본 연구에서는 광여기 방법으로 176Hf, 201Hg 이성질체에 대한 결과를 최초로 얻었다. The gated CsF detection system described here provides an improvement on earlier techniques for the measurement of ㎲ nuclear fluorescence excited by pulsed bremsstrahlung. The use of CsF rather than the standard NaI(Tl) scintillator reduces the dead time of the detector by a factor of about 5 and the sample-to-converter separation by an order-of-magnitude. This extends the utility of the method to temporal domains poorly investigated previously and with a concomitant decrease in data collection times. This utility was illustrated by new results for the pumping of the ㎲ isomers of 181Ta and 81Br and the first demonstration of the photoexcitation of the metastables of 176Hf and 201Hg. It is expected that with further refinements in the reduction of EMI and improvements in the signal-to-noise ratio it will be possible to detect fluorescence with a halflife near 1 ㎲ pumped by bremsstrahlung.

감마선 레이저에 대한 전반적 고찰

홍진수 순천향대학교 기초과학연구소 1995 순천향자연과학연구 논문집 Vol.1 No.2

As the pumping methods for the development of gamma-ray lasers (grasers) neutron pumping and photoexcitation pumping methods have been propposed. It was demonstrated experimentally that the latter was more proper and efficient. Here the grasers have the photon energies in the range of 6∼120 keV (λ= 0.1 ∼ 2 Å) and so one should use the deexcitations between the nuclear excited states. The grasers pumped by neutron flux have been in main stream of their developments, but those basically have the limitation for output, i.e., single-photon output with the pumping power possible up to now. In 1982 Collins et al. proposed the upconversion which could be considered as the application of Raman effect to nuclear physics to lead the feasibility of grasers. Main frames of his proposal for grasers consisted of (1) host matrix; (2) flashed X-ray generator as pumping source; (3) nuclear candidates as laser active medium. Each component was discussed, and as the most tangible nuclear candidate, based on nuclear data sheets, the schematic energy levels of 178㎖ HF were shwon, and future experiments to be necessary for those were described.

내부전반사에 대한 고찰 Ⅱ : 구스-행켄 시프트 Goos-Ha¨nken shift

홍진수,박해윤 순천향대학교 기초과학연구소 2001 순천향자연과학연구 논문집 Vol.7 No.2

The detailed phenomenon of total internal reflection, Goos-Hanken shift, is discussed based on electromagnetic theory when two prisms are separated in narrow gap comparable to the wavelength of incident electromagnetic wave. The shift is quite important to estimate the optical properties of materials and thus it can be applied to enhance the performance of simple devices such as microscope, optic communication and optoelectronics.

이차원 영상을 이용한 물체의 삼차원 좌표구현

홍진수,박해윤 순천향대학교 기초과학연구소 2001 순천향자연과학연구 논문집 Vol.7 No.2

We need a whole processing to extract object's informations in the image. So, useful informations were found to use any operators with contrast to object's informations that are transformed to numerical informations. Generally, image processing is dealt with two-dimensional informations are not able to extract the depth-cue information, because it has only Hue, Saturation, Intensity informations. Thus, we need to use three- dimensional information so to extract to exactly object's informations. For the depth-cue information, theoretical methods with disparity are binocular disparity, monocular disparity, shade disparity and time-delay disparity, the other experimental methods with embodiment are Red-Blue polarization, othorgonal polarization, lenticular polarization and parallax barrier. In this paper, binocular disparity is discussed in theoretical methods to extract the depth-cue information. The depth-cue informations are obtained with image processing techniques such as modified modified Canny edge detect method, edge, edge pairs, coordinate pairs and dynamic programming. Also, we presented new method so that it could use to exact object's information with only edge informations in the case that disparity values are not well known.

고출력 펄스 레이저로 증착된 유기필름

홍진수,채희백,안성기,박해윤 순천향대학교 기초과학연구소 2001 순천향자연과학연구 논문집 Vol.7 No.2

유기발광 응용에 성공적으로 사용되어 새로운 물질을 개발할 때 기준으로 사용되는 Alq_3와 TPD필름을 기존의 증착법(열증착법과 스핀코터 기술)을 대체할 수 있는 고출력펄스레이저로 합성하였다. 펠릿 타겟은Q-스위칭 Nd:YAG 레이저의 532 nm와 355 nm를 사용하여 2&10^-6 Torr압력 하에서 용발시킨다. 슬라이드 유리 위에 증착된 필름은 유기발광 디바이스에 사용될 가능성이 있는지 알기 위해 다음과 같은 조사를 하였다: PL,AFM, 흡수 스펙트라, XRD. 355 nm 레이저로 유기필름을 증착하면 532 nm 경우의 필름보다 결합이 적고, 특히 열증착 필름보다 스트레스를 덜 받는다는 사실을 알 수 있다. 또한 타겟의 구조가 Alq_3 다를지라도 레이저 증착법으로 합성된 Alq_3 필름은 열증착과 동일한 구조를 갖는다는 사실을 알 수 있다. 어느 레이저를 사용하건 증착된 필름은 결정구조를 확인할 수 없을 정도로 비정질을 이룬다는 사실을 알 수 있다.