• ETRI Journal
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• v.13 no.4
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• pp.52-57
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• 1991

We fabricated very high. speed PIN Photodiode module for the application of high speed optical receiver. OMVPE was used for the growth of InP layer on InGaAs absorption layer. The structure was the combination of mesa and planartype. Fabrication procedure was more complicated than simple mesa or simple planar type structure because we used semiinsulating InP substrate in order to reduce stray capacitance. The results at-5V were as follows : dark current was less than 1nA, capacitance was 0.55pF, and cutoff frequency was above 3GHz, and rise and fall time was about 100ps.

• Proceedings of the Optical Society of Korea Conference
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• 2003.07a
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• pp.88-89
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• 2003

현대 시대에 광통신 시스템은 안정적이고 높은 단일 모드를 갖는 광원을 필요로 한다. 이 조건을 만족하는 λ／4 phase shifted DFB는 높은 단일모드 생성을 보였으나 high spatial hole burning문제점을 가지고 있다. λ／4 phase shift를 사용하지 않은 dual-pitch grating DFB가 소개되었지만 제작상의 어려움을 가지고 있다. 또 다른 구조인 selection-free tapered stripe DFB lasers가 제안되었는데 제작이 간단하면서도 높은 단일모드 생성을 보였다. (중략)

• 대한생식의학회:학술대회논문집
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• 1996.11a
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• pp.54.2-55
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• 1996

• 공원문화
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• s.33
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• pp.16-19
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• 1986

이 글은 1984년 9월 14-19일 제1차 세계문화공원회의가 미국 콜로라도주 Mesa Verde 국립공원에서 개최되었을 때 본회이사인 김 헌규 박사가 발표한 내용을 간추린 것인데 미국에서 원문도착이 늦어져 이제 게재하게 됨을 밝힌다.

• Proceedings of the Korean Vacuum Society Conference
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• 1994.06a
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• pp.73-73
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• 1994

• Journal of the Korean Society of Propulsion Engineers
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• v.3 no.1
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• pp.78-85
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• 1999

Burning characteristics of solid propellants embedded with four kinds of metal wires(Ag, Cu, Al, Ni-Cr wire) were studied with varying wire diameters(O.10.8 mm) lot N-5 propellant. It was found that the order of the burning rate increment ratio($r_w$/$r_sb$) was Ag wire > Cu wire > Al wire> Ni-Cr wire which was the same as the order of the magnitude of thermal diffusivity. The burning rate increment ratio($r_w$/$r_sb$) of N-5 propellant was less than that of composite Propellant because of the difference of adiabatic flame temperature and flame structure. When Ag, Cu and Al wire having high thermal diffusivity were embedded in N-5 propellant, the plateau and mesa characteristics of the double base propellant were disappeared, but not disappeared in the case of propellant embedded with Ni-Cr wire due to its poor thermal conductivity.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.3
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• pp.447-456
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• 1999

Objective: The purpose of this study was to evaluate outcome of intracytoplasmic sperm injection (ICSI) using epididymal and testicular sperm in patients with azoospermia. Methods: From March, 1993 to May, 1999, a retrospective clinical analysis was done of a total of 140 cycles in 112 patients who underwent ICSI. Subjects were divided into three groups: ejaculated-ICSI group included 42 cycles in 34 patients with ejaculated sperm who underwent ICSI due to severe oligospermia and past history of failed or poor fertilization in the previous in vitro fertilization and embryo tranfer (IVF-ET) cycles, microsurgical epididymal sperm aspiration and intracytoplasmic sperm injection (MESA-ICSI) group included 50 cycles in 42 patients with congenital absence of the vas deferens (CAVD) or unreconstructable obstructive azoospermia and testicular sperm extraction and intracytoplasmic sperm injection (TESE-ICSI) group included 48 cycles in 36 patients with no spermatozoa which can be retrieved from epididymis or non-obstructive azoospermia. Results: Normal two-pronuclear fertilization rates were similar in three groups: 64.4% for ejaculated-ICSI group, 59.4% for MESA-ICSI group and 60.4% for TESE-ICSI group. The pregnancy rates were 26.2%, 26.0% and 25.0% respectively. There were no significant differences in the fertilization, cleavage, and clinical pregnancy rates among ICSI cycles using ejaculated, epididymal and testicular sperm. Conclusion: Epididymal and testicular sperm obtained in azoospermic patients can fertilize oocyte successfully and may lead to be similar fertilization rates and clinical pregnancy rates to ejaculated sperm.

• Information and Communications Magazine
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• v.24 no.7
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• pp.69-78
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• 2007

본고에서는 광대역 무선 멀티미디어 재난통신 기술의 기술개발 동향 및 표준화 동향을 알아본다. 기술 개발동향의 경우는 정보시스템, 센서망, 통신 인프라 측면에서 개발하고 있는 프로젝트 내용을 분석하고 필요한 기술들을 알아본다. 표준의 경우는 MESA, ETSI (EMTEL, TETRA, SES) 등 주요 표준 단체의 표준 추진현황을 살펴보고 내용을 설명한다.

• Proceedings of the KIEE Conference
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• 1984.07a
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• pp.207-208
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• 1984

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.28-28
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• 2002