• 제목/요약/키워드: Collapse line

검색결과 111건 처리시간 0.024초

저손실 융착접속을 이용한 광자결정 광섬유 간섭계 (Fiber Interferometers Based on Low Loss Fusion Splicing of Photonic Crystal Fibers)

  • 안진수;김길환;이관일;이경식;이상배
    • 한국광학회지
    • /
    • 제21권5호
    • /
    • pp.200-205
    • /
    • 2010
  • 본 논문에서는 포토닉 밴드갭 광섬유(Photonic Bandgap Fiber: PBGF) 사이에 중공광섬유(Hollow Optical Fiber: HOF)를 융착 접속시켜 만든 광섬유 간섭계와 넓은 모드 면적을 가지는 광자결정 광섬유(Large Mode Area-Photonic Crystal Fiber: LMA-PCF)사이에 HOF를 융착접속시켜 만든 광섬유 간섭계의 온도 및 스트레인에 대한 광학적 특성을 분석하였다. PBGF 또는 LMA-PCF와 HOF의 융착접속시 광섬유내 공기구멍을 최대한 유지하도록 융착조건을 최적화하여 접속 손실을 줄였다. PBGF와 HOF로 구성된 광섬유 간섭계의 온도 및 스트레인에 대한 민감도는 각각 15.4 pm/$^{\circ}C$와 0.24 pm/${\mu}\varepsilon$으로 측정되었으며, LMA-PCF와 HOF로 구성된 광섬유 간섭계의 온도 및 스트레인에 대한 민감도는 각각 17.4 pm/$^{\circ}C$와 0.2 pm/${\mu}\varepsilon$으로 측정되었다.

안면다한증에서 경요도 절제용 전기절제 내시경을 이용한 교감신경간 소작술 (T2 Sympathicotomy with TUR Electroresectoscope for Facial Hyperhidrosis)

  • 최봉춘;이영철;이효근;김찬
    • The Korean Journal of Pain
    • /
    • 제11권2호
    • /
    • pp.220-225
    • /
    • 1998
  • Background: The patients of facial hyperhidrosis have been known that they had much difficulties in interpersonal relationships and social activities due to excessive hidrosis when they were in stress, hot weather, or having meals. Previous drug therapy and stellate ganglion block have only temporary effects. The surgical method, $T_1$ sympathetomy has the risk of Hornor's syndrome. For that reasons, the sympathicotomy of proximal and distal portions of $T_2$ sympathetic ganglion with electroresectoscope used in transurethral resection seemed to be appropriate procedure, and we would like to report the results of our procedure. Method: Under the general anesthesia with semi-sitting position, and the portal was made through the small incision along the upper border of the 4th rib at the crossing point of mid-axillary line. After the partial collapse of lung by insufflation of 300 to 500 ml of $CO_2$, $T_2$ sympathetic ganglion was identified and resected proximally and distally with electro-cauterization. Finally the lung was expanded by limiting flow until the airway pressure reached 30 to 40 cm$H_2O$, and the wound was closed after removal of electroresectoscope. Result: There was no postoperative complication requiring surgical interventions. The facial sweating was stopped immediately after the operation and all the patients appeared to be satisfied. Conclusion: $T_2$ sympathicotomy with TUR electroresectoscope is thought be the minimal invasive and highly successful method in the treatment of facial hyperhidrosis. But longer terms follow-up will be needed to prove this result.

  • PDF

노후화된 농업용 저수지의 효율적인 리모델링 방법 (Effective Method for Remodeling of Deteriorated Agricultural Reservoirs)

  • 이영학;이달원
    • 한국농공학회논문집
    • /
    • 제59권4호
    • /
    • pp.43-52
    • /
    • 2017
  • This study analyzed pore water pressure, earth pressure and settlement through laboratory model tests in order to suggest the effective remodeling method in the case of reinforcing the upstream and downstream slope of deteriorated reservoirs that has no cores and filters or is not functional. The method of remodeling the upstream slope using dredge soil is first prevent seepage by installing the core, and the leakage water can be rapidly discharged through a filter installed on the downstream slope. Therefore, it is considered a highly efficient method of remodeling that reduces piping phenomena and increasing the storage capacity of the reservoir. The variation of earth pressure without the core and filter was greater than with it, while the change largely showed in the upstream slope, the downstream slope did not show any significant changes. The remodeling method of the downstream slope with the core appeared differently pore water pressure depending on the presence of the vertical and horizontal filters. In the upstream slope, the pore water pressure rises sharply, the base and middle gradually increased, and the downstream slope appeared small. The pore water pressure of embankment with a vertical and horizontal filter will be smaller than without it. The remodeling of deteriorated reservoir that does not have the function of the filter, the vertical filter must be installed in a position that is higher than the expected seepage line by removing portions of the downstream slopes. Since the horizontal filter is an important structure that provides stable drainage during an earthquake or concentrated leak, it is necessary to examine any change in the seepage characteristics depending on the filter intervals via three-dimensional finite element analysis, and it should be connected to the tow-drain to reduce the possibility of the collapse of the reservoir.

FUNS - Filaments, the Universal Nursery of Stars. I. Physical Properties of Filaments and Dense Cores in L1478

  • Chung, Eun Jung;Kim, Shinyoung;Soam, Archana;Lee, Chang Won
    • 천문학회보
    • /
    • 제43권1호
    • /
    • pp.45.1-45.1
    • /
    • 2018
  • Formation of filaments and subsequent dense cores in ISM is one of the essential questions to address in star formation. To investigate this scenario in detail, we recently started a molecular line survey namely 'Filaments, the Universal Nursery of Stars (FUNS)' toward nearby filamentary clouds in Gould Belt using TRAO 14m single dish telescope equipped with a 16 multi-beam array. In the present work, we report the first look results of kinematics of a low mass star forming region L1478 of California molecular cloud. This region is found to be consisting of long filaments with a hub-filament structure. We performed On-The-Fly mapping observations covering ~1.1 square degree area of this region using C18O(1-0) as a low density tracer and 0.13 square degree area using N2H+(1-0) as a high density tracer, respectively. CS (2-1) and SO (32-21) were also used simultaneously to map ~290 square arcminute area of this region. We identified 10 filaments applying Dendrogram technique to C18O data-cube and 13 dense cores using FellWalker and N2H+ data set. Basic physical properties of filaments such as mass, length, width, velocity field, and velocity dispersion are derived. It is found that filaments in L~1478 are velocity coherent and supercritical. Especially the filaments which are highly supercritical are found to have dense cores detected in N2H+. Non-thermal velocity dispersions derived from C18O and N2H+ suggest that most of the dense cores are subsonic or transonic while the surrounding filaments are transonic or supersonic. We concluded that filaments in L~1478 are gravitationally unstable which might collapse to form dense cores and stars. We also suggest that formation mechanism can be different in individual filament depending on its morphology and environment.

  • PDF

JERS-1 SAR를 이용한 가은 폐탄광 지역 지반침하 관측 (Observation of the Ground Subsidence in the Abandoned Gaeun Coal Mining Area using JERS-1 SAR)

  • 정한철;김상완;김복철;민경덕;원중선
    • 자원환경지질
    • /
    • 제37권5호
    • /
    • pp.509-519
    • /
    • 2004
  • JERS-1 L밴드 SAR 위성에서 얻어진 25개의 레이더간섭도를 이용하여 1992년 11월 5일부터 1998년 10월 1일 사이 경상북도 문경시 가은읍 폐탄광 일대의 지반 침하량을 측정하였다. SAR 영상에서 긴밀도가 높은 고정 산란체(PS: permanent scatterer)를 이용한 시계열 분석을 통해서 지반침하를 계산하였고, 현장조사된 균열등급 분포도와 비교하였다. 고정된 산란체는 1차적으로 진폭값과 간섭쌍의 긴밀도 영상을 이용하여 계산하였는데, 산악지역에 비해 도심지역에서 우세하게 선정되었다. 계산된 변위량은 붕락과 같은 급격한 비선형의 변위는 제외되고, 영상 획득 기간 내의 평균 변위량이다. 연구지역 내 계산된 주시방향으로의 평균 지표면 변위속도는 0.19cm/yr이고, 추정오차는 0.18cm/yr이다. 그리고 옛 가은 본갱의 중심부와 가은역 맞은편 일대에서 관측된 침하량은 0.49cm/yr, 1.66cm/yr로 연구지역에서 가장 뚜렷한 침하 양상을 보였다.

시티 노마드의 라이프스타일과 패션스타일에 관한 연구 (A Study on the Lifestyle and Fashion Style of City Nomads)

  • 김혜정
    • 패션비즈니스
    • /
    • 제21권5호
    • /
    • pp.15-29
    • /
    • 2017
  • The purpose of this study is to examine modern people's lifestyle and identify their needs by analyzing clothing behavior through city nomads' attitudes in dairy life, tastes, and methods to pursue in their life. This study tries to understand substitute values as ethical life emerging recently, free life style of mental emotion, clothing behaviors, and fashion style represented by the results. Upon observing city nomads' fashion trend, tunics symbolizing flexibility and comfort and simultaneously reflect colors in a monk style or from basic items that have been used. City nomads' fashion trend also reveals androgynous freeness-and-easiness. City nomads reflect a folksy inspiration, and different cultural perspectives appear in a mixed fashion. Multi-purpose gypsy/boho style is ideal for traveling and occupying smaller spaces in line with the nomadic lifestyle reflectings an American casual image partially by way of gypsy or bohemian nuances. Motorcycle jeans symbolizing functionality for traveling are becoming a part of everyday life. The fashions discussed are categorized as urban, tourer, sports and road. Everyday sportswear - athleisure - is attracting attention enabling a healthy and sound lifestyle. Athleisure is fashion wear harmonizing workplace with leisure, and everyday life and social gatherings. Athleisure represents a significant collapse of the boundary of high fashion and street fashion. Urban- tech wear is light and enables modern people to perform garment and gear functions simultaneously, making storage useful using various technical devices by elevating activity and functionality. Urban outdoor fashion holding functionality and adding modern fashion in appearance has appeared.

Cultural and Social Implications of Metrosexual Mode

  • Oh, Yun-Jeong;Cho, Kyu-Hwa
    • 패션비즈니스
    • /
    • 제10권3호
    • /
    • pp.117-128
    • /
    • 2006
  • The purpose of this study was to understand changes of the current young generation's lifestyle, aesthetic attitude for an appearance, and way of thinking by making a close investigation into metrosexual, the recent mode, and find out its cultural and social implications. As a method of the study, the literature and the Internet data were reviewed. Articles from newspapers, magazines and the Internet were chosen roughly from the year 2000 to now because metrosexual mode remarkably boomed before and after 2000. Books related to the theory on the mode in a costume culture were referred. Also, articles in daily newspapers which dealt with cultural and social issues were reviewed, fashion magazines for men such as Esquire and GQ showing the new trend in men's lifestyle and fashion were examined, and the Internet providing us the latest news from cultural and social topics to fashion trends were investigated. The backgrounds of the rise of metrosexual mode were a collapse of stereotypes in various fields, spread of lookism in a visual image period, extension of commercialism, and expansion of men's character casual trend. Metrosexual was defined as an urban male with a strong aesthetic sense who spends a great deal of time and money on his appearance and lifestyle. His fashion style was characterized by slim and flowing silhouette, feminine and luxurious materials such as transparent chiffon, silk and cotton with a light and soft touch, and a knitted wear with a flowing line, a wide variety of vivid and pastel colors, floral and geometric patterns, and the decorative details like lace, beads, embroidery, and fur. From spread of this mode, two cultural and social implications were extracted. Firstly, the current young generation's aesthetic standards for the perfect man changed from macho man to considerate man who had a good appearance and this suggested that a conventional sex role broke down. Secondly, men began to explore for their own identity escaping from traditionally standardized masculinity that they had been forced to follow.

환경친화적인 초임계 이산화 탄소 공정을 이용한 포토레지스트의 합성 (Synthesis of Photoresist Using Environmental-benign Supercritical $CO_2$ Processes)

  • 허완수;이상원;박혜진;김장엽;홍유석;유기풍
    • 폴리머
    • /
    • 제28권6호
    • /
    • pp.445-454
    • /
    • 2004
  • 반도체의 최소 회로 선폭이 더욱 미세해지면서 포토레지스트 현상액으로 초임계 이산화 탄소를 응용하려는 연구가 진행되고 있다. 초임계 이산화 탄소는 환경친화적이며, 미세 화상 공정 단계에서 표면장력이 작아 패턴 붕괴를 막을 수 있고, 고분자에 대한 선택적 용해도가 큰 장점을 지니고 있다. 본 연구에서는 초임계 이산화 탄소 전용 포토레지스트의 기본 수지 합성을 위해 t-부틸 메타크릴레이트 (t-BMA)와 과불소화 데실 메타크릴레이트 (F17MA)를 단량체로 이용하여 다양한 몰비로 공중합하였고, 공중합체의 초임계 이산화 탄소에 대한 용해도를 분석하였다. 합성된 고분자와 광산 발생제를 섞어 제조한 포토레지스트는 노광을 통해 초임계 이산화 탄소에 대한 용해도가 감소되므로, 합성된 고분자의 초임계 이산화 탄소 전용 포토레지스트로서의 가능성을 확인하였다.

황천항해중인 선수선교선의 내항성능평가기준 설정 방안에 관한 연구 - 해난사고 실례를 통한 갑판침수 평가기준치 설정에 대한 개선방안 고찰 - (A Methodology to Provide the Criterion for the Seakeeping Performance of a Fore-Bridge-Ship in Rough Seas - The Problem on the Application of the Past Deckrwetness Criterion Based on the Accident of a Fore-Bridge-Ship -)

  • 공길영;김철승
    • 해양환경안전학회지
    • /
    • 제7권3호
    • /
    • pp.17-28
    • /
    • 2001
  • The wheelhouse front glass of a Fore-Bridge-Ship (Ro-Ro Ship) was broken by the shipping of water in rough seas, and then the flooding of seawater into the wheelhouse caused the uncontrollable condition of the ship. The hull which was entered into the floating condition rolled severely, and the heavy rolling caused secondary damage such as the collapse of a lot of cargo. It was an incredible accident because the height of bow freeboard was about 2.5 times higher than the standard height of minimum bow freeboard regulated by the International Load Line Convention(1966). And it would be also difficult for navigators to imagine a great deal of seawater flooding into the wheelhouse because the front glass was positioned at about 20m height above the sea surface. In this paper, we carried out the evaluation for the safety navigation of the Fore-Bridge-Ship numerically against ship's speed and encountering angle to the wave in each sea state of rough sea, by using the integrated seakeeping performance index (ISPI) which is able to evaluate synthetically the safety operation of ships. And then the problem on the application of the past criteria proposed as the safety navigation of a merchant ship was clarified by inquiring the dangerousness of the shipping of water at her bow deck, which caused the breakage of the wheelhouse front glass.

  • PDF

개별요소법을 이용한 도로함몰 붕괴양상 추정에 관한 연구 (A Study on Estimation of the Collapse Pattern of Road Sink Using Distinct Element Method)

  • 함명수;박선우;이현동
    • 한국방재안전학회논문집
    • /
    • 제12권2호
    • /
    • pp.57-63
    • /
    • 2019
  • 서울시에서 2010년부터 2016년까지 발생한 도로함몰 발생 건수는 총 4,737건으로 매년 증가하여 사회문제도 대두되고 있다. 특히 도로함몰은 충적층이 두껍게 분포하는 송파구와 구로구에 집중되어 나타나는데 이는 하수관로 또는 지하철이 통과하는 지역의 지반특성이 큰 영향을 미치기 때문이다. 도로함몰에 대한 대책방안을 수립하기 위해서는 누수가 발생하는 구간에서의 지반특성과 지반거동의 관계를 정확하게 규명하는 것이 필요하다. 이 논문에서는 충적층에 가장 흔하게 나타나는 사질토와 점성토를 대상으로 개별요소법 프로그램 중 하나인 EDEM 프로그램을 이용하여 지층 내 공동의 위치 및 크기를 달리하여 시뮬레이션을 수행하였다. 그 결과 점성토 지반보다 사질토 지반에서 함몰 규모가 크게 발생한 것으로 나타났으며, 점착력이 없는 사질토 지반에서는 지하 공동의 깊이가 깊고 지하 공동의 규모가 증가할수록 도로함몰이 쉽게 발생하는 양상을 보인 반면, 점착력이 있는 점성토 모델에서는 지하 공동의 깊이가 얕을수록 도로함몰이 쉽게 발생하는 양상을 보였다.