• 제목/요약/키워드: Multi Ground

검색결과 1,136건 처리시간 0.03초

확률론적 내진성능평가를 위한 다자유도 교량구조물의 지진취약도해석 (Seismic Fragility Analysis for Probabilistic Seismic Performance Evaluation of Multi-Degree-of-Freedom Bridge Structures)

  • 김학수;송종걸
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.269-272
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    • 2008
  • 구조물의 지진취약도곡선은 임의의 크기를 가진 지진에 대하여 구조물에 어느 규모이상의 손상이 발생할 확률을 의미하는 것으로 구조물의 내진성능평가 및 손실평가 하는데 아주 중요하다. 본 논문은 선진국의 지진취약도 추정기법을 분석하여 국내 실정에 적합한 지진취약도 추정 기법을 확립하기 위한 연구방법론을 제시하는 데 그 목적이 있다. 이를 위해 우선 지진취약도함수의 개발현황을 조사하였다. 그 다음 이러한 평가방법을 국내에 적용하기 위하여 국내의 교량구조물을 분류하였다. 마지막으로는 PSC Box 거더교에 대해서 지진취약도곡선을 평가하였다. 평가 결과 구조물의 분류와 손상상태는 구조물의 손상평가와 지진취약도해석에 아주 큰 영향을 미치는 것을 확인할 수 있었다.

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영상 인페인팅을 이용한 고품질의 가려짐 영역 보간 방법 (A High-Quality Occlusion Filling Method Using Image Inpainting)

  • 김용진;이상화;박종일
    • 방송공학회논문지
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    • 제15권1호
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    • pp.3-13
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    • 2010
  • 본 논문에서는 한 장의 기준 영상과 그에 상응하는 참 깊이 맵을 이용하여 가상의 다중 시점 영상 생성 시 발생하는 가려짐 영역 보간 방법을 제안한다. 이 방법은 영상 인페인팅 기술과 각각의 깊이 정도에 따른 층별 보간 기술을 이용한다. 우선, 기준 영상을 깊이 정보에 따라 여러 개의 층으로 분할한다. 각각의 층에 대해 가려짐 영역 내의 화소들은 영상 인페인팅 기술을 이용하여 보간한다. 마지막 단계 에서 개별적으로 보간된 층 영상들은 하나로 합성되어 가상 시점의 영상을 이룬다. 영상을 깊이 정보에 따라 분할함으로써, 각 깊이 정도에 대한 텍스처의 연관성을 보존하며 보간할 수 있으므로 기존의 방법에 비하여 보다 정확하고 세밀한 가려짐 영역 보간이 가능하다. 본 논문에서는 여러 가지 실험 결과를 통하여 제안한 방법의 효율성을 입증하였다.

회전익 항공기 다기능시현기의 이상시현을 방지하기 위한 DVI 케이블 개선 (DVI cable Improvement for Preventing MFD Abnormal Display of a Rotary-wing Aircraft)

  • 김영목;정상규;조재포;최두현
    • 한국항공우주학회지
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    • 제46권9호
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    • pp.782-789
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    • 2018
  • 한국형 기동헬기(KUH)의 다기능시현기(MFD)는 항공기 운용 중 임무컴퓨터(MC)로부터 영상정보(항법, 비행, 생존, 지형 및 정비 관련 정보)를 입력받아 시현한다. 체계개발 단계에서 식별된 MFD 이상시현(화면 깜박임 현상 등)은 항공기 초도양산 과정에서 DVI 케이블 차폐 성능 개선과 DVI 케이블 장착 경로 변경을 통하여 해소하였다. 항공기 납품 후 1~2년 정도 경과하였을 때 MFD 이상시현이 다시 발생하였고, 파생형헬기 시험평가 과정에서도 식별되었다. 이러한 MFD 이상시현의 해결을 위하여 항공기 체계 단위의 종합 검토를 수행하였고, DVI 케이블의 개선을 통한 설계 개선방안을 도출하였다. 본 논문에서는 MFD 이상시현의 발생원인을 분석하였고, 설계 개선방안 검토과정을 정리하였다. 그리고 설계 개선사항에 대한 타당성을 DVI 케이블 조립체 비교시험, SIL/지상/비행시험 결과를 바탕으로 입증하였다.

간척지 설치 온실의 난방부하 특성 분석 (Analysis of Heating Load Characteristics for Greenhouses Constructed in Reclaimed Lands)

  • 남상운;신현호
    • 한국농공학회논문집
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    • 제59권6호
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    • pp.1-8
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    • 2017
  • The purpose of this study was to provide basic data for development of environmental design technology for greenhouses constructed in reclaimed lands. We analyzed the climatic conditions around seven major reclaimed land areas in Korea, which have a plan to install advanced horticultural complexes. The characteristics of heating load through the thermal environment measurement of the greenhouse in Saemangeum were analyzed. The part to be applied to the environmental design of the greenhouses in reclaimed lands were reviewed. The overall heat transfer coefficient of the experimental greenhouse with the aluminum screen and multi-layer thermal curtain averaged $3.79W/m^2^{\circ}C$. It represents a 44 % heat savings rate compared with plastic greenhouses with a single covering, which was significantly lower than that of the common greenhouses with 2-layer thermal curtains. This is because the experimental greenhouse was installed on reclaimed land and wind was stronger than the inland area. Among the total heating load, the transmission heat loss accounted for 96.4~99.9 %, and the infiltration loss and the ground heat exchange were low. Therefore, it is necessary to take countermeasures to minimize the transmission heat loss for greenhouses constructed in reclaimed lands. As the reclaimed land is located on the seaside, the wind is stronger than the inland area, and the fog is frequent. Especially, Saemangeum area has 2.6 times stronger wind speed and 3.4 times longer fog duration than the inland area. In designing the heating systems for greenhouses in reclaimed lands, it is considered that the maximum heating load should be calculated by applying the wind coefficient larger than the inland area. It is reasonable to estimate the operation cost of the heating system by applying the adjustment factor 10 % larger than the average in calculating the seasonal heating load.

Outcome of Limited Resection for Lung Cancer

  • Cho, Jeong-Su;Jheon, Sang-Hoon;Park, Sung-Joon;Sung, Sook-Whan;Lee, Choon-Taek
    • Journal of Chest Surgery
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    • 제44권1호
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    • pp.51-57
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    • 2011
  • Background: Up to now, lobectomy, bilobectomy and pneumonectomy combined with extensive lymph node dissection have been regarded as the standard procedures for non-small cell lung cancer (NSCLC). In high-risk patients, however, limited resection (LR) has been attempted as a salvage procedure, and, recently, indication for LR has been extended to selected cases with early-stage NSCLC. Material and Methods: Among the 773 patients who underwent surgical procedures for NSCLC in Seoul National University Bundang Hospital from May 2003 to December 2008, 43 patients received LR. Medical records of these patients were retrospectively reviewed. Results: Mean age at operation was $66.0{\pm}12.4$ years, and there were 30 males. Twenty-five patients underwent conservative limited resection (CLR) and 18 underwent intentional limited resection (ILR). Indications for CLR were multiple primary lung cancer in 9 (9/25, 36%) and severe concomitant diseases in 5 (5/25, 20%). Of these, 6 patients underwent segmentectomy and 19 received wedge resection. During the follow-up period of $28.0{\pm}17.8$ months, 15 patient developed recurrent lung cancer. ILR was selectively performed in lesions almost purely composed of ground glass opacity (${\geq}$95%), or in small solid lesions (${\leq}$2 cm). Of these, 11 patients underwent segmentectomy and 7 underwent wedge resection. During the follow-up period of $31.7{\pm}11.6$ months, no patient developed recurrence. Conclusion: Intermediate-term outcome of LR for early-stage lung cancer is comparable to that of standard operation. For the delineation of the indications and appropriate surgical techniques for LR, prospective randomized multi-institutional study may be expedient.

Silicon Nitride Layer Deposited at Low Temperature for Multicrystalline Solar Cell Application

  • Karunagaran, B.;Yoo, J.S.;Kim, D.Y.;Kim, Kyung-Hae;Dhungel, S.K.;Mangalaraj, D.;Yi, Jun-Sin
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.276-279
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    • 2004
  • Plasma enhanced chemical vapor deposition (PECVD) of silicon nitride (SiN) is a proven technique for obtaining layers that meet the needs of surface passivation and anti-reflection coating. In addition, the deposition process appears to provoke bulk passivation as well due to diffusion of atomic hydrogen. This bulk passivation is an important advantage of PECVD deposition when compared to the conventional CVD techniques. A further advantage of PECVD is that the process takes place at a relatively low temperature of 300t, keeping the total thermal budget of the cell processing to a minimum. In this work SiN deposition was performed using a horizontal PECVD reactor system consisting of a long horizontal quartz tube that was radiantly heated. Special and long rectangular graphite plates served as both the electrodes to establish the plasma and holders of the wafers. The electrode configuration was designed to provide a uniform plasma environment for each wafer and to ensure the film uniformity. These horizontally oriented graphite electrodes were stacked parallel to one another, side by side, with alternating plates serving as power and ground electrodes for the RF power supply. The plasma was formed in the space between each pair of plates. Also this paper deals with the fabrication of multicrystalline silicon solar cells with PECVD SiN layers combined with high-throughput screen printing and RTP firing. Using this sequence we were able to obtain solar cells with an efficiency of 14% for polished multi crystalline Si wafers of size 125 m square.

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3D FEM analysis of earthquake induced pounding responses between asymmetric buildings

  • Bi, Kaiming;Hao, Hong;Sun, Zhiguo
    • Earthquakes and Structures
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    • 제13권4호
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    • pp.377-386
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    • 2017
  • Earthquake-induced pounding damages to building structures were repeatedly observed in many previous major earthquakes. Extensive researches have been carried out in this field. Previous studies mainly focused on the regular shaped buildings and each building was normally simplified as a single-degree-of-freedom (SDOF) system or a multi-degree-of-freedom (MDOF) system by assuming the masses of the building lumped at the floor levels. The researches on the pounding responses between irregular asymmetric buildings are rare. For the asymmetric buildings subjected to earthquake loading, torsional vibration modes of the structures are excited, which in turn may significantly change the structural responses. Moreover, contact element was normally used to consider the pounding phenomenon in previous studies, which may result in inaccurate estimations of the structural responses since this method is based on the point-to-point pounding assumption with the predetermined pounding locations. In reality, poundings may take place between any locations. In other words, the pounding locations cannot be predefined. To more realistically consider the arbitrary poundings between asymmetric structures, detailed three-dimensional (3D) finite element models (FEM) and arbitrary pounding algorithm are necessary. This paper carries out numerical simulations on the pounding responses between a symmetric rectangular-shaped building and an asymmetric L-shaped building by using the explicit finite element code LS-DYNA. The detailed 3D FEMs are developed and arbitrary 3D pounding locations between these two buildings under bi-directional earthquake ground motions are investigated. Special attention is paid to the relative locations of two adjacent buildings. The influences of the left-and-right, fore-and-aft relative locations and separation gap between the two buildings on the pounding responses are systematically investigated.

『돈키호테』에 나타난 모리스꼬의 정체성을 중심으로 (The Identity of Morisco in Don Quijote de La Mancha)

  • 임주인
    • 비교문화연구
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    • 제38권
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    • pp.265-295
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    • 2015
  • This article is concerned about a reason for which Cervantes participates an arabic author named Benengeli and morisco translator in his work instead of christian author. From the multi-cultural point of view, the time in which Don Qujote was published, belongs to the Golden Age. In other words, the society can not be supported by the ideology of Purity of Blood in that the morisco, converso (Christian Jewish) have been permitted to coexist in the name of christian proselyte or New Christian despite of invisible discrimination. An invisible discrimination is based on the prejudice and negative stereotype of Old Christian against the New Christian. Cervantes offers an o open space for readers to participate in the creative reading, giving up the absolute authority of author named Benengeli. The deep-rooted prejudice against morisco or muslim author makes the readers of Don Quijote do reinterpret the contents and have question about his sincerity. This disbelief is partly on the basis of hypothesis that Don Quijote would be passed on orally by an arabic or morisco. Leaving the hypothesis alone, Romance, festival performances of morisco or the aljamia literature in the Iberian Peninsula have the chivalry or knights of the Occident. The chivalry in Romance of morisco means that morisco would seek assimilation into the mainstream of Occidental Christian community. At the same time, morisco would be faced with the dilemma of loss of religious identity. But Taqiyya, islamic doctrine, offsets the dilemma between yearning to assimilate into mainstream and religious conscience of morisco in that Taqiyya permits morisco to convert to Christianity in case that they are in danger of life or the following risk. From this point of view, There is no room for doubt about the fact that Taqiyya contributed to social assimilation or multicultural society of the Iberian Peninsula. It has been a long time since a narrow-minded religious dogma and ideology became a anachronistic relic in multicultural society of Spain such as the Purity of Blood. From a relative viewpoint, Don Quijote provides a ground for the collective intelligence among christian, muslim(morisco) and converso through a liberal community between readers and authors who form a pluralistic society.

전술 에드혹 환경에서 이종망 게이트웨이 구조 및 시뮬레이션 연구 (Heterogeneous Network Gateway Architecture and Simulation for Tactical MANET)

  • 노봉수;한명훈;권대훈;함재현;윤선희;하재경;김기일
    • 한국시뮬레이션학회논문지
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    • 제28권2호
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    • pp.97-105
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    • 2019
  • 전술 에드혹 환경은 개별 지상 노드 간 분산적인 형태의 자율망으로 구성되므로 네트워크의 생존 가능성 및 유연성 측면에서 효과적이나 기동 간 통신 시 제한된 출력, 지형특성, 이동성 등의 제약으로 인하여 잦은 링크 단절 및 음영지역이 발생할 수 있다. 반면 위성 통신망은 지상 기동 망에 비해 지형특성과 이동성을 극복한 광역 무선 링크를 제공할 수 있는 장점이 있으나 상대적으로 한정된 대역폭 및 고지연 특성의 망이다. 미래 전장 환경에서 기존의 단독망 형태의 제약사항을 극복하고 지휘 통제 통신의 신뢰성 및 효율성을 높이기 위해서는 이종망 게이트웨이(Heterogeneous network gateway, HNG)를 중심으로 위성 통신망을 포함한 다계층 통합 네트워크 구조가 요구된다. 본 논문에서는 전술 에드혹 환경에서 위성-전술 에드혹 망을 통합적으로 고려하고 유통되는 임무 트래픽의 플로우 특성에 기반하여 신뢰성 있는 데이터 전달이 가능한 이종망 게이트웨이 구조 및 세부 알고리즘을 제시한다. 시뮬레이션은 네트워크 수준의 시뮬레이터인 Riverbed Modeler를 활용하여 제시하는 구조의 유효성을 확인하였다.

초고층 건물의 지반을 고려한 2D 및 3D 동적해석에 의한 거동 비교 연구 (A Comparative Study on the Behavior of High-rise Buildings by 2D and 3D Dynamic Analysis with Considering the Ground)

  • 유광호;백용;김승진
    • 한국지반환경공학회 논문집
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    • 제20권10호
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    • pp.5-14
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    • 2019
  • 최근 우리나라에서도 지진이 발생하여 대도시의 초고층 건물의 내진안정성에 대한 관심이 높아져 이에 대한 연구가 증가하고 있다. 또한 대부분의 내진설계 및 해석은 지반을 간접적으로 고려하고 있고, 3D 동적해석을 이용한 내진해석 연구는 미비한 실정이다. 따라서 본 연구에서는 지반을 포함한 SSI 연속체 모델에 기초한 2D 및 3D 동적해석을 수행하고 거동을 비교 분석하였다. 동적해석을 위해 지반범용해석 프로그램인 MIDAS GTS NX를 이용하여 선형시간이력해석을 수행하였다. 이를 위해 초고층 건물이 기반암 위에 시공되고 표층에 묻혀있는 것으로 가정하고, 선정된 파라미터를 기준으로 민감도 분석을 수행하였다. 동적거동은 수평변위, 층간변위비, 휨응력, 취약부를 이용하여 비교 분석하였다. 대부분의 경우, 2D 동적거동은 3D보다 크게 산출하여 더 보수적인 결과를 보였으며, 취약부의 수와 크기는 증가하는 것으로 나타났다.