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UAV Autopilot Design under External Disturbances

  • Eun, Youn-Ju;Hyochoong Bang;Tahk, Min-Jea
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.40.3-40
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    • 2002
  • Unmanned Aerial Vehicle(UAV) needs autonomous flight capability to accomplish various mission objectives. For this objective, the autopilot is a key element in the UAV system design. The principal goal of autopilot is to guide the aircraft under varying external disturbances throughout the mission phases. The external disturbances include gravity effect, wind gust, and other unexpected obstacles. The gust affects the aircraft flight performance to a significant extent. UAV's low speed, light weight, and the absence of human judgment makes un predictable gust more dangerous. Autopilot design in general takes the gust effect into account to satisfy flight performance requirement. In this study..

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A design of PCI-based reconfigurable verification environment for IP design (IP 검증을 위한 PCI 기반 리프로그램머블 설계 기능 에뮬레이션 환경 구현)

  • 최광재;조용권;이문기
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.65-68
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    • 2002
  • The verification of software part and HW/SW interface suffer from the absence of the hardware platform at the end of partitioning and coding phase in design cycle. In this paper we present the design of easy verification for hardware design. Hardware and software engineer can verify their software program and hardware design for a chip that is emulated in proposed verification environment. Besides, designer can easily design the DEMO system.

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MAGNETIC CURTAILMENT OF THE SHOCK-INDUCED THERMAL INSTABILITY

  • Hong, Seung-Soo;Koo, Bon-Chul
    • Journal of The Korean Astronomical Society
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    • v.17 no.2
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    • pp.115-125
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    • 1984
  • Effect of magnetic field on the thermal instability is studied in the radiatively cooling region behind an interstellar shock of moderate propagation velocity (${\sim}10\;km/sec$). It is shown that the presence of interstellar magnetic field of a few micro gauss is very effective in preventing the thermal instability from building-up density concentration. In the absence of magnetic field, the shock-induced thermal instability amplifies preshock density inhomogeneity by more than an order of magnitude. However, in the presence of magnetic field, the amplified density contrast is shown to be only a factor 2.

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Understanding the Material Removal Mechanisms of Abrasive Water Jet Drilling Process by Acoustic Emission Technique

  • Kwak, Hyo-Sung;Kovacevic, Radovan
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 1998.03a
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    • pp.40-52
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    • 1998
  • Among the non-traditional machining methods, Abrasive waterjet machining process shows big promise in drilling difficult-to-machine materials due to its numerous advantages such as absence of heat affect zone and thermal distortion. Acoustic emission signal technique is used to understand about material removal mechanisms during abrasive waterjet drilling process. More information about the drilling process is derived through frequency decomposition of auto regressive moving average modeling representing acoustic emission signals.

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Stereotactic Body Radiation Therapy for Treatment of Spinal Bone Metastasis

  • Cihan, Yasemin Benderli
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.937-938
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    • 2016
  • Stereotactic body radiation therapy (SBRT) appears an effective and safe treatment modality for spinal bone metastasis, which can enhance local control and improve quality of life. Life expectation, predicted fracture risk, localization, quality, size and number of metastasis and presence or absence of nerve compression seem to be important factors in decision-making for treatment. Further studies are needed to identify subsets of patient which will most benefit from treatment.

Route Stability of Mobile Ad Hoc Network Based on Proximity and Mobility (근접성과 이동성에 기초한 Ad Hoc망의 경로안정도)

  • 안성범;안홍영
    • Proceedings of the IEEK Conference
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    • 2003.07a
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    • pp.39-42
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    • 2003
  • Due to the highly dynamic topology and absence of any fixed infrastructure, stability of selected path in Ad Hoc Networks is of prime importance. The frequent route failure and high control overhead in routing protocol consumes system resources and lead to degraded system performance. In this paper we present route stability metrics reflectting relative position and velocity of nodes, which help determine a stable route.

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The Impacts of Korea Train Express Service Quality on Railroad Management Performance (고속철도(KTX)의 서비스품질이 철도 경영성과에 미치는 영향)

  • Park, Heung-Soon;Ju, Yong-Jun
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1744-1759
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    • 2007
  • This study intended to identify the problems of the railroad which are raised as one of the 21C next-generation but to define the direction for the absence of the national policy and examine the competitiveness of railway transportation which is a Green Network with low environmental destruction and high energy efficiency as the continuable means of transportation for the 21st century with superiority to energy crisis caused by high oil price, conclusion of the Kyoto Protocol for worsened air pollution, and reduced cost of traffic jam.

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Comparative Study on the Mutagenic Activity of Phenothiazines by UV-A Irradiations (UV-A 조사에 의한 Phenothiazines의 돌연변이원성 비교 연구)

  • 김봉희;박영아
    • Journal of Food Hygiene and Safety
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    • v.9 no.1
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    • pp.15-21
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    • 1994
  • The mutagenic activity of four phenothiazine derivatives such as chlorpromazine, perphenazine, trifluoperazine and thioridazine in conjunction with UV-A irradiation or not based on the Ames plate incorporation test in the presence and absence of liver microsomal enzyme(S9 fraction). None of these compounds and their photo-excited were detected as mutagen in the Salmonella microsome assay with TA 98 and TA 100.

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Evaluation of Researches on Strategy Content in Healthcare Organizations

  • Suh, Won-S.
    • Korea Journal of Hospital Management
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    • v.12 no.4
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    • pp.68-95
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    • 2007
  • The purpose of this paper is to provide the comprehensive review of empirical investigations in strategy content in healthcare organizations. Given the absence of relevant reviews in assessing an external validity of strategy content research in the healthcare industry, the paper, by taking convergent view, discern two main streams of research in the school of content: (1) the strategy-structure-performance (SSP) contingent, and (2) competitive strategies which test the propositions that business strategy, industry structure (IO economics). Finally, the paper suggests some future direction for research in this area.

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A Study on Margin (여백에 관하여)

  • 진정식
    • Proceedings of the Korea Contents Association Conference
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    • 2004.05a
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    • pp.121-127
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    • 2004
  • Just as it Is said that the darkness of the universe is not absence of light but the dark material itself, Moo-geuk and Tae-geuk are one thing, and an empty space is not empty but full of nothing, margin in fine art is a living space where negative space and positive shape do not exist separately but are connected to each other and combined into a unified space to perish ultimately.

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