초고속 전송에 대한 Ultrashort Laser Pulse의 새로운 스펙트럼 분석

전진성,조형래,오용선 韓國海洋大學校電波通信硏究所 1999 電波通信硏究所論文集 Vol.1 No.-

본 논문에서는, Class-2 PRS 모델의 전달함수인 Raised-Cosine 펄스를 이용하여 극초단 레이저펄스의 전송특성을 분석하였다. 이는 Class-1 PRS 모델에서와 같이 부분응답시스템의 수정된 모델로부터 얻어지는 고차원펄스를 이용하여 그 차수의 증가에 따라 FWHM폭이 현저히 감소하여 분석하고자 하는 극초단펄스의 형태에 근접하는 펄스를 제시하였으며, 그 스펙트럼과 전송대역폭도 차수에 따라 일률적으로 유도되므로 Gaussian, Sech형태의 펄스 같은 고전적인 방법과는 달리 광범위하고 정확한 전송특성을 분석하는데 매우 유용함을 밝혔다. 먼저, 부분응답시스템의 일반적인 모델을 수정하여 어떤 형태의 고차원펄스도 적용할 수 있는 새로운 방법을 제안하였다. 그리고 제안된 모델을 이용하여 어떠한 형태의 FWHM을 가지는 극초단펄스의 전송에 대한 새로운 분석 방법을 제안하였다 제안된 방법을 사용하여, 설정 펄스 폭을 τ=1(㎰)으로 설정, 고차원펄스의 차수 n=1~100에서 얻어지는 FWHM 1(㎰)~100(fs)의 극초단펄스의 스펙트럼을 제시하였고, Class-2 PRS 모델의 FWHM 폭이 Class-1 PRS 모델보다는 차수 n에 따라서 약 50~100(fs)정도 좁은 FWHM 폭을 가짐을 밝혔다. 이에 대한 전송특성은 레이저펄스의 보편적인 신호방식인 Unipolar 체계로 설정하여, 가능한 펄스간격에 따른 PSD를 유도하여 제시하였다. 이러한 결과들은 고전적인 실험 방법과는 일치함을 물론 미래 극초단펄스 연구에 대한 혁신적인 방법으로 사용될 수 있을 것이다. In this paper, we analyze transmission characteristics of ultrashort laser pulses using the property of Raised-cosine pulse which are systematically obtained following Class-2 PRS model. The high-order pulses are easily derived from a modified PRS system model as Class-1 PRS model. This may be based on the fact that the spectra and bandwidths of the high-order pulses are beautifully related to their orders. And we make clear they are very useful to cover wider area and more accurate transmission characteristics of ultrashort pulses than Gaussian or Sech pulse approximations used conventionally. First modifying the generalized PRS system model, we propose a new model for deriving any type of high-order pulse. And we offer a novel analysis method of ultrashort pulse transmission which has any shape and FWHM, using the proposed model. In addition, by fixing the pulse range τ=1(㎰) and varying the order of the pulse from n=1 to n=100, we obtain spectra of ultrashort pulses with 1(㎰)~100(fs) FWHM's, and width of FWHM in the Class-2 PRS model 50~100(fs) smaller than Class-1 PRS model. As a one-step further, we derive PSD's of their pulse trains when they are applied to Unipolar signaling scheme. These PSD's are decided in the range of possible pulse intervals. All of these results are not only coincided with some conventional experimental works but also will be applied to any pioneering ultrashort pulse in the future.

Identification of a Gene Cluster in Streptomyces spectabilis-spectinomycin producer

오태진,김형준,송재경 선문대학교 대학원 2000 대학원학술논문집 Vol.2 No.-

Spectinomycin (Spc) is an aminoglycoside antibiotic which shows remarkable broad-spectrum. From a chromosomal cosmid library of Streptomyces spectabills, a Spc producer, a clone (pSPM8) was isolated by homology to the dTDP-glucose 4,6-dehydratase and aminotransferase genes which obtained from S. spectabilis genome using a polymerase chain reaction. From this clone, a 5.8-kb DNA region was sequenced and found to encode four open reading frames and one Incomplete reading frame. The putative orfl protein reveals 29% amino acid sequence homology of putative myo-inosltol-2-dehydrogenase from Vibrio anguillarnm. The orf2 is about 46% homologous to putative myo-inositol-1-monophosphotase of Mycobacterium leprae. The orf3 showed strong homology (67.4%) to putative export protein (spcT) from S. flavopersicus. The amino acid sequence deduced from 0114 showed a high similarity (70.8%) to a spectinomycin resistance gene (spcN) from S. flavoperslcus. Expression of orf4 in E. coti BL21 showed the spectinomycin resistance.

연장 가골에 골 이식 대체물 투여가 골 경화에 미치는 영향 : 가토 경골에서의 방사선 및 골 밀도의 변화 Changes of Radiography & Bone Mineral Density in the Tibia of Rabbits

오창욱,김풍택,박병철,송해룡,박일형,백준호,박형진 경북대학교 병원 2003 경북대학교병원의학연구소논문집 Vol.7 No.1

목적 : 골 연장술 후 생기는 연장 가골에 황화 칼슘과 이종 이식골을 투여하여 골 경화 속도에 대한 영향을 알아보기 위한 실험이었다. 연구대상 및 방법 : 성장중인 뉴질랜드 화이트 토끼(2.0-2.5㎏)의 경골 간부에 골막을 보호하고, 절골술을 시행하고, 5일간의 휴지기후 외고정 장치를 이용하여 1주일 동안 7㎜가 연장될 때까지 하루 1㎜씩 2회의 리듬을 가지고 골 연장을 실시하였다. 제1 실험 군 7마리에는 연장이 끝난 직후 황화 칼슘(Osteoset^(ⓡ), Wright medical USA) 1정, 제 2 실험 군 7마리에는 이종 이식골의 일종인 Lubboc 5㎟을 각각 연장된 가골 부에 주입하고, 단순 연장한 대조군 7마리와 함께, 방사선 및 골 밀도비를 측정하고 추시하여, 골 경화의 진행속도를 비교하였다. 방사선 촬영은 전후면 및 측면사진을 1주 간격으로 촬영하였고, 골밀도 측정은 DEXA(dual energy X-ray absorptionmetry, Lunar^(ⓡ)) 장치를 2주일 간격으로 시행하였다. 결과 : 방사선 소견상, 제 1실험군의 연장가골의 완전 경화시간은 평균 14주, 제 2실험군은 154 주로 각각 대조군의 16.9주보다 단축되었으며, 골 밀도 비에서도, 두 실험군에서 최고치가 대조군의 값보다 높고, 최고치까지의 경과기간도 빨랐다. 결론 : 본 연구에서 연장 가골에 황화칼슘 및 이종 이식골의 투여가 골 경화의 기간을 단축시킬 수 있고, 외고정 장치의 빠른 제거에 도움이 될 수 있음을 알았다. Purpose : This study was designed to know the effect of calcium-sulfate and xenograft on the distracted callus after lengthening. Materials & Methods : We had operation of subperiosteal osteotomy and external fixation on the tibial diaphysis of young New Zealand White rabbits(2.0-2.5㎏); after 5 days of latency period, 7㎜(1㎜/day, 2times/day) of tibial lengthening was reached in a week. At 1 week after lengthening, the 1st experimental group of 7 rabbits received a pellet of calcium sulfate(Osteoset, Wright medical, USA) in the distraction gap, and the 2nd experimental group of 7 rabbits received 5㎜ 2 of xenogrfat(Lubboc) in the distraction gap. But, the control group of 7 rabbits did not receive any of above materials. We compared three groups with the changes of radiographic findings at every week and bone mineral ratio(DEXA) at every two weeks. Results : The time to complete consolidation of distraction callus of both experimental group(calcium sulfate;14 weeks, xenograft; 15.4 weeks) was shorter than that of control group(16.9 weeks) in radiographic findings. Maximum value of bone mineral ratio of distraction callus was higher and the time to reach the highest value was also shortened in the both experimental group compared to control group. Conclusion : By use of bone substitutes as like calcium sulfate or xenograft in the distraction callus with external fixator, it may be possible to shorten the consolidation period and the fixator-wearing period.

패턴 Top Rounding 효과를 고려한 패턴 붕괴 전산모사

이형주,박준택,오혜근 한양대학교 이학기술연구소 2002 이학기술연구지 Vol.5 No.-

패턴의 선폭이 100 nm 이하로 작아짐에 따라 발생하는 패턴의 붕괴 현상은 반도체생산과 수율에 많은 영향을 미친다. 패턴 붕괴 현상은 리소그래피 과정 중 현상 후 세척액을 건조하는 과정에서 주로 발생하며 세척액의 표면장력에 의한 모세관 현상이 주된 원인으로 알려져 있다. 패턴 붕괴 현상을 시뮬레이션하기 위하여 패턴이 세척액에 외해서 균일한 압력을 받을 때와 집중 압력을 받을 때의 역학적 모델을 세우고 각각의 모델을 통하여 선폭과 패턴간의 거리에 따른 임계 높이/선폭비 (aspect ratio)를 계산하여 실제 실험 결과와 일치하는 모델을 선정하였다. 시뮬레이션 결과 패턴의 top 부분이 둥근 (rounded top) 패턴이 각진 (flat p) 패턴에 비해 변형이 줄어들 수 있다는 것을 확인할 수 있었다. The pattern size is reduced as the device is more integrated. The resist deformation phenomenon has been a serious problem under 100 nm line width pattems. The most applicable model for an existing empirical result is chosen to create a simulation tool by comparing the two mechanical models when a pattern receives a distributed pressure or a concentrated pressure from the rinse liquid. Based on the chosen model, the critical aspect ratio with respect to line width and space can be calculated. The simulated results show that the pattern collapse phenomenon is reduced for a rounded top resist profile rather than for aflat top profile

다환방향족 탄화수소에 오염된 토양에서 분리한 Pseudomonas sp. KK1의 생리학적 특성

윤병준,강형일,오덕철 제주대학교 생명과학연구소 2001 제주생명과학연구 Vol.4 No.-

Strain KK1 was isolated from soil contaminated with polycyclic aromatic hydrocarbons and able to mineralize anthracene, naphthalene, and phenanthrene. In this study, strain KK1 was tested to evaluate carbazole-degrading potential using radiorespirometry. When KK1 was pre-grown on phenanthrene the cells were able to mineralize carbazole much more rapidly, suggesting a possible close linkage between the pathways for catabolism of carbazole and phenanthrene. Such an increase in carbazole degradation was not appreciable when KK1 was pre-grown on naphthalene. Strain KK1 was identified as the genus Pseudomonas with over 90 % confidence based on BIOLOG system and FAME analysis. Analysis of PLFAs extracted from kk1 cells on carbazole medium revealed that lipids 10:0 3OH, 17:0 cyclo, and 18:0 were representatives produced or significantly increased in response to carbazole. Tests for antibiotics provided the data that strain KK1 was resistant to antibiotic ampicillin, but susceptibile to chloramphenicol, gentamycin, kanamycin, streptomycin, and tetracycline. Strain KK1 demonstrated strong resistance to most heavy metals such as Ba, Cd, Fe, Hg, Pb used in this study.

영아의 상순에 발생한 유피낭종

김성오,문성환,이제호,최형준,최병재 大韓小兒齒科學會 2004 大韓小兒齒科學會誌 Vol.31 No.3

유피낭종(dermoid cyst)은 표피형태의 상피세포로 이루어진 낭종의 벽에 피부부속조직을 포함하는 발생학적 낭종이다. 눈썹 부근이나 구강저의 중심선에 호발하지만 혀, 입술, 협점막의 병소도 보고된 바 있다. 이 병소는 천천히 커지고 무통성이며 임파선비대는 동반하지 않는다. 내용물은 피지성, 화농성등이며 크기는 수 mm에서 12cm까지 다양하다. 조직학적 특징은 상피세포 이장과 낭종벽내의 땀샘, 피지샘, 모낭동의 피부부속조직의 존재이다. 유피낭종의 치료는 완전절제이다. 완전한 절제시 재발의 가능성은 거의 없다. 본 증례의 2세 여자 환아는 1년 전에 넘어진 이후 상순에 딱딱한 것이 생겼다는 것을 주소로 연세대학교 치과대학병원 소아치과에 내원하였다. 임상 구강검사 결과 둥근 고무질감의 종괴가 상순에서 관찰되었다. 조직학적 검사를 위해 조직생검을 시행하였으며, 낭종의 벽에서 피지샘이 관찰되었다. 이에 상순에서는 드물게 발생하는 유피낭종으로 진단되어 보고하는 바이다. Dermoid cyst is a developmental cyst that is lined by epidermis-like epithelium and contains dermal adnexal structures in the cyst wall. Dermoid cyst most occur in the eye brow although occasionally develop in other locations such as midline of the floor of the mouth, tongue, lip and buccal mucosa. The lesion is slow growing and painless without lympadenopathy. The contents of the dermoid cyst can be caseous or sebaceous. The size can vary from a few millimeters to 12cm in diameter. Histologically, dermoid cyst is lined by epidermis and adnexaes such as sweat gland, sebaceous glands and hair follicles are present in the cyst wall. The 2-year-old female of this case visited Department of Pediatric Dentistry, College of Dentistry, Yonsei University with a chief complaint of the emergence of mass on her upper lip. An excisional biopsy was carried out for a histological examination and sebaceous gland was observed in the cyst wall. The lesion was diagnosed as dermoid cyst. Delmoid cyst does not recur if complete excision is accomplished.

영구치 TWINNING예 대한 증례보고

김성오,최형준,이종갑,이승일 大韓小兒齒科學會 1997 大韓小兒齒科學會誌 Vol.24 No.4

As one of the developmental disturbance in shape of teeth, a twinning very rare frequency in permanent teeth. Because it is possible to diagnose the twinning by use of the radiograph, it is very important to detect this anomaly early by careful examining the radiographs. The twinning produces several orthodontic problem such as crowding, protrusion, ectopic eruption of adjacent teeth. Therefore it is necessary, in proper time, the extraction and orthodontic treatment should perform.

복합적인 레지스트 패턴 붕괴현장의 역학적 해석

이형주,박준택,안일신,김옥근,오혜근 한양대학교 이학기술연구소 2003 이학기술연구지 Vol.6 No.-

패턴의 선폭이 100nm이하로 작아짐에 따라 패턴이 부러지고, 휘고, 떨어져 나가는 현상이 발생하는데 이러한 현상을 패턴 붕괴 현상이라고 하며, 반도체 생산과 수율에 많은 영향을 미친다. 패턴 붕괴 현상은 리소그래피 과정 중 현상 후 세척액을 건조하는 과정에서 주로 발생하며 세척액의 표면장력에 의한 모세관 현상이 주된 원인으로 알려져 있다. 패턴 붕괴 현상을 시뮬레이션하기 위하여 패턴이 세척액에 의해서 균일한 압력을 받을 때와 집중 압력을 받을 때의 역학적 모델을 세우기 각각의 모델을 통하여 선폭과 패턴간의 거리에 따른 임계 높이/선폭비 (aspect ratio) 를 계산하여 실제 실험 결과와 일치하는 모델을 선정하였다. 또한 패턴 내부에 생기는 stress 에 의한 부러짐 현상과 패턴 과 레지스트 패턴 하부 층 사이의 접착력 부족으로 발생하는 떨어짐 현상을 해석하였다. High aspect ratio resist patterns with dimensions below 100 nm often bend, break or tear. These phenomena are generically called "resist pattern collapse". Pattern collapse is a very serious problem in fine patterning of less than 100 nm critical dimension (CD), so that it decreases the yield. In order to mechanically analyze this phenomenon and create its simulator, two models have been made and compared. In this paper, various approaches with various analyses are made to understand pattern collapse. Also, the critical aspect ratio for 100 nm node, that determines whether pattern collapse happens or not, can be calculated with these approaches. Finally, tear type caused by insufficiency of adhesion strength between the substrate and the resist is analyzed with a point of view of the surface free energy.

항균 활성을 가진 천연약재의 검색

송형석,이지연,오성준,백남인,김해영 경희대학교 생명자원과학연구원 2000 硏究論文集 Vol.21 No.-

We investigated the antimicrobial activity of the hot-water extracts and methanol extracts from medicinal plants. Sixty-two samples were tested by disk diffusion method at concentrations of 5,000ppm and 10,000ppm. Seven species of medicinal plants showed a significant antimicrobial activity against various food-borne microorganisms.

아르곤 레이저를 이용한 광중합 수복재의 물리적 성질에 관한 연구

최형준,주상호,김성오,이종갑 大韓小兒齒科學會 1998 大韓小兒齒科學會誌 Vol.25 No.2

The purpose of this study is to evaluate and compare the results of argon laser for 5 seconds, argon laser for 10 seconds, and visible light for 40 seconds photo-polyerization in compressive strength, microhardness, curing depth, temperature rising during polymerization, and polymerization shrinkage. Hybrid type composite resin(Z-100) and compomer (Dyract) were used to be compared. The compressive strength was measured by an Instron (1mm/min cross head speed) in 60 specimens and the microhardness of the surface was expressed by Vickers Hardness Number (VHN) in 30 specimens. The curing depth was evaluated comparing the different values of upeer and lower VHN according to irradiation time and thickness for the light sourece polymeriaztion in 60 specimens. the temperature rising during photopolymerization was observed by the temperature change with thermocouple sensitizer beneath 40 specimens at th argon laser for 10 seconds and visible light 40 seconds irradiation. the polymerization shinkage was evaluated by calculating the decrease of % volume by using a dilatometer in 30 specimens. The results were as follows : 1. In the case of compressive strength, the argon laser polymerization groups were higher than visible light group in Z-100 (p<0.05). In Dyract, the argon laser 5 seconds group did not show a significant difference with the visible light 40 seconds group. The argon laser 10 seconds group showed the markedly low value when compared with other g개ups (p<0.05) 2. In micriohardness, Z-100 was better than Dyract when comparing by VHNs(p<0.05) ; however, there was not a significant difference between two materials in the visible light 40 seconds group and the argon laser 10 seconds groups. 3. In the study of curing depth, Z-100 showed the consistent polymerization in argon laser irradiation because there was no difference in the VHN decrease according to the thickness change. Over the thickness control, the results did not show a significant difference between visible light and argon laser group in Z-100 ; however, in the case of Dyrct, the visible light 40 seconds group was better than the argon laser groups(p<0.05). 4. There was a significant difference between the two materials in temperature rising during polymerization (p<0.05), but not a significant difference between irradiation times. 5. There was not a significant difference between the two materials in polymerization shrink-age. The argon laser 5 seconds group was smaller than the other groups (p<0.05). It could be concluded that z-100 polymerization was recommended to use the argon laser for reduction of the irradiation time while Dyract was recommended to use the visible light polymerization.