• 제목/요약/키워드: Open A. I.

검색결과 1,788건 처리시간 0.03초

Young Open Clusters: Their Uses in Star Formation Studies

  • Lim, Beomdu
    • 천문학회보
    • /
    • 제40권2호
    • /
    • pp.28.1-28.1
    • /
    • 2015
  • Open clusters are one of stellar systems consisting of a few hundreds to thousands of stars. The cluster members are, in general, believed to be a coeval stellar population at the same distance, and therefore they have almost the same properties in chemical composition and kinematics. Owing to these advantages, the clusters are utilized in many astronomy studies, such as the calibrations of distance and stellar age scales, assessments of stellar evolution theories, and the chemical evolution of the Galactic disk. Young open clusters are, inter alia, superb objects to study star formation process as most of stars are known to be formed in clusters. In this talk, I will review the uses of these young open clusters in star formation studies based on the ongoing work of our research group on the stellar initial mass function, an age spread problem, mass accretion rate of pre-main sequence stars, and a feedback of high-mass stars on surroundings.

  • PDF

융합기술연구소 실험공간의 특성과 오픈랩 시스템에 관한 연구 (A Study on Spatial Characteristics of the Converging Technology Laboratory and Open-Lab System)

  • 최진희
    • 교육시설
    • /
    • 제16권5호
    • /
    • pp.19-26
    • /
    • 2009
  • This study attempts to find out the spatial characteristics of the converging technology laboratory. For this, the understanding of the nature of converging technology and its necessary system requirements are crucial. The foremost concern lies in the 'flexibility' of the laboratory space, i.e. 'open-lab system', because of the multi-disciplinary spatial arrangement which is supposed to be open to a number of different research fields in the same building cluster. From the case analysis, this study reveals that in order to maximize the adjustability, the module based space unit plan should be considered at the earliest stage. In addition, it is also found from the analysis that the linkage of the communication spaces such as seminar room, auditorium, lounge, rest room, dining room, and corridors should be dealt with a higher degree of sophistication, since these facilitate the interaction of information at the behavioral level.

Interoperability of Spatial Data through Open Web Map Server

  • Cho, D.S.;Jang, I.S.;Min, K.W.;Park, J.H.
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
    • /
    • pp.488-490
    • /
    • 2003
  • Over the past few years, a number of studies have been made on web map services, which enable the GIS user to access spatial data through the web. They, however, have focused on only implementation techniques separately, such as map client implementation, map server implementation, communication between client and server, and the map data representation. Therefore, it is hard to share and practical use the spatial data, because they does not ensure interoperability in heterogeneous map servers. In this paper, we have designed and implemented the web map server with open architecture, which complies with the standard interfaces proposed by OpenGIS Consortium (OGC). In particular, we have extended the OGC’s interfaces for a map server to support one or more data sources. This paper has contributed to construction and practical use of web map services by newly proposing the method of implementation of a map server, which could be reused regardless of the types of data sources.

  • PDF

오픈소스 활용 드론에 대한 보안 위협과 Telemetry Hijacking을 이용한 군용 드론 공격 시나리오 연구 (A study on security threats to drones using open source and military drone attack scenarios using telemetry hijacking)

  • 이우진;서경덕;채병민
    • 융합보안논문지
    • /
    • 제20권4호
    • /
    • pp.103-112
    • /
    • 2020
  • 최근 민간에서는 취미/레저용 드론에 대한 관심이 많아지고 있으며 군에서도 북한, 미국, 이란 등 다양한 나라에서 드론을 활용하여 정찰, 파괴 등의 군사 목적으로 사용하게 되면서 우리 군 내에서도 드론 부대를 창설하여 드론 운용을 하는 등 다양한 드론 관련 연구가 진행되고 있다. 특히, 최근 드론 개발자들은 드론 비행 제어 소스코드의 크기가 커지고 기능들이 많아짐에 따라 오픈소스를 가져와 활용하는 것에 익숙해지고 있으며 별도의 보안 취약점에 대한 점검없이 활용하고 있다. 그러나 실제로 이러한 오픈소스는 공격자가 접근가능하기 때문에 다양한 취약점에 노출될 수 밖에 없으며, 본 논문에서는 Telemetry Hijacking 기법을 활용하여 이러한 취약점과 연계하여 오픈소스를 사용하는 군용 드론에 대한 공격 시나리오를 제시한다.

Lateral-torsional buckling of prismatic and tapered thin-walled open beams: assessing the influence of pre-buckling deflections

  • Andrade, A.;Camotim, D.
    • Steel and Composite Structures
    • /
    • 제4권4호
    • /
    • pp.281-301
    • /
    • 2004
  • The paper begins by presenting a unified variational approach to the lateral-torsional buckling (LTB) analysis of doubly symmetric prismatic and tapered thin-walled beams with open cross-sections, which accounts for the influence of the pre-buckling deflections. This approach (i) extends the kinematical assumptions usually adopted for prismatic beams, (ii) consistently uses shell membrane theory in general coordinates and (iii) adopts Trefftz's criterion to perform the bifurcation analysis. The proposed formulation is then applied to investigate the influence of the pre-buckling deflections on the LTB behaviour of prismatic and web-tapered I-section simply supported beams and cantilevers. After establishing an interesting analytical result, valid for prismatic members with shear centre loading, several elastic critical moments/loads are presented, discussed and, when possible, also compared with values reported in the literature. These numerical results, which are obtained by means of the Rayleigh-Ritz method, (i) highlight the qualitative differences existing between the LTB behaviours of simply supported beams and cantilevers and (ii) illustrate how the influence of the pre-buckling deflections on LTB is affected by a number of factors, namely ($ii_1$) the minor-to-major inertia ratio, ($ii_2$) the beam length, ($ii_3$) the location of the load point of application and ($ii_4$) the bending moment diagram shape.

양악 전방분절골절단술과 이부 성형술을 통한 개방교합의 치험례 (TREATMENT OF ANTERIOR OPEN BITE WITH BIMAXILLARY ANTERIOR SEGMENTAL OSTEOTOMY AND GENIOPLASTY)

  • 황용인;홍순민;박준우;이건주;조형준;천세환;박양호
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • 제34권3호
    • /
    • pp.355-364
    • /
    • 2008
  • Skeletal anterior open bite is a difficult problem to correct in orthodontic treatment. To treat adult patients who have skeletal anterior open bite, we considered two methods. Combination treatment of orthodontics & surgery and camouflage orthodontic treatment. In adults, treatment of severe skeletal anterior open bite consists mainly of surgically repositioning the maxilla or the mandible. However, camouflage therapy is often the treatment of choice for skeletal open bite patients who have mild to moderate skeletal discrepancies when growth modification is no longer possible. But excellent results generally require careful coordination of the orthodontic and surgical phases of treatment. This is a case report of a skeletal anterior open bite patients who were treated with orthodontic treatment and orthognathic surgery. First case was diagnosed as skeletal class I malocclusion & bimaxillary protrusion with anterior open bite, and finally treatment ended for removal of open bite with orthodontic procedure and bimaxillary anterior segmental osteotomy surgery. Second case was diagnosed as skeletal class II malocclusion with open bite & mandibular retrusion, and was treated with only camouflage orthodontics because she feared to have a surgery. In a regular follow up visit after debonding we proposed to the patient advanced genioplasty, and in her agreement her facial esthetics was improved through the surgery.

iA-Canvas를 이용한 통합 관리 시스템 구현 (Implementation of The Integrated Management System using iA-Canvas)

  • 김석찬;김기태;김제민;유원희
    • 디지털산업정보학회논문지
    • /
    • 제6권1호
    • /
    • pp.169-179
    • /
    • 2010
  • iA-Canvas is HMI program which is the industrial automation application developed based on the Java language, and can run on any OS such as Windows, UNIX, Linux. The iA-Canvas is built on object-oriented open structure and consider network functionality and user experience as a system of centralized management and distributed management. iA-Canvas is composed of several components such as Builder, IO Server, Viewer, and Web Service Module and provides a GUI control environment. This paper explains design and implementation of iA-Canvas that is a tool for development of integrated management system, and shows practical examples of integrated management system that use iA-Canvas.

Insertion of Alkali Metals into Open Framework, TaPS6 by Using Alkali Metal Halide Fluxes: Single Crystal Structures of K0.18TaPS6, K0.28TaPS6, and Rb0.09TaPS6

  • Do, Jung-Hwan;Dong, Yong-Kwan;Kim, Jung-Wook;Hahn, Song-I;Yun, Ho-Seop
    • Bulletin of the Korean Chemical Society
    • /
    • 제26권8호
    • /
    • pp.1260-1264
    • /
    • 2005
  • Three new quaternary tantalum thiophosphates, $K_{0.18}TaPS_6,\;K_{0.28}TaPS_6,\;and\;Rb_{0.09}TaPS_6$ have been synthesized by using reactive alkali metal halide fluxes and structurally characterized by single crystal X-ray diffraction techniques. The crystal structures of $K_{0.18}TaPS_6,\;K_{0.28}TaPS_6,\;and\;Rb_{0.09}TaPS_6$ contain 3-dimensional open framework anions, $[TaPS_6]^{x-}$(x = 0.09, 0.18, 0.28) with the empty channel which disordered alkali metal cations, $K^+\;and\;Rb^+$ are located in. Crystal data: $K_{0.18}TaPS_6$, tetragonal, space group$I4_1$/acd (no. 142), a=15.874(3) $\AA$, c=13.146(4) $\AA$, V=3312.7(12) ${\AA}^3$, K, Z=16, R1=0.0545. Crystal data: $K_{0.28}TaPS_6$, tetragonal, space group $I4_1$/acd (no. 142), a=15.880(2) $\AA$, c=13.134(3) $\AA$, V=3312.1(10) ${\AA}^3$, Z=16, R1=0.0562. Crystal data: $Rb_{0.09}TaPS_6$, tetragonal, space group I41/acd (no. 142), a=15.893(3) $\AA$, c=13.163(4) $\AA$, V=3324.7(15) ${\AA}^3$, Z=16, R1=0.0432.

Modified FR-4의 임상적용례 (CLINICAL APPLICATION OF MODIFIED FR-4)

  • 송재혁;이긍호;최영철
    • 대한소아치과학회지
    • /
    • 제28권2호
    • /
    • pp.323-328
    • /
    • 2001
  • 전치부 개교합은 상 하악 전치부가 폐구 시 절단 기능에 필수적인 수직피개가 결여되어 있는 상태를 말한다. 일반적인 원인으로는 손가락 빨기, 혀 내밀기, 유아성 연하, 비호흡 부전, 골격성장의 이상 또는 이들이 복합적으로 작용되어 나타날 수 있으며, 어떤 종류의 부정교합과도 함께 나타날 수 있다. 전치부 개교합을 위한 치료 방법은 다양하지만, Rolf Fr$\"{a}$nkel에 의해 고안된 Fr$\"{a}$nkel appliance(FR-4)는 골격성 I급 혹은 II급 부정교합과 함께 나타난 개교합의 치료에 특히 효과적인 것으로 알려져 있다. 서양인에서는 골격성 II급 부정교합이 높은 빈도로 나타나고, 개교합도 이와 함께 나타나는 경우가 많다. 그러나 동양인에서는 골격성 III급 부정교합의 빈도가 높고, 개교합 또한 이와 같은 골격형태와 함께 나타나는 경우가 흔히 있다. 이러한 문제점을 갖는 환자에 있어서 전통적인 FR-4의 사용이 개교합의 교정에 도움이 되었을지라도, 골격성 III급 부정교합을 악화시키는 것으로 나타났다. 두 가지 문제점을 동시에 교정하기 위하여, labial bow를 하악 전치부에, labial pads를 상악 전치부에 위치시킨 modified FR-4를 고안하게 되었다. 다음의 임상례는 전치부 개교합을 동반한 골격성 III급 부정교합을 보이는 환자를 대상으로, 전통적인 FR-4와 modified FR-4를 이용하여 치료한 결과를 비교한 것이다. 첫 번째 임상례는 전통적인 FR-4를 사용한 경우로서, 전치부 개교합은 개선되었으나 골격성 III급 부정교합의 형태가 심해졌다. 그러나 두 번째와 세 번째 임상례에서는 modified FR-4를 사용한 결과, 전치부 개교합과 III급 부정교합이 동시에 개선된 것으로 나타났다.

  • PDF