• 제목/요약/키워드: NextGen

검색결과 51건 처리시간 0.021초

FAA의 차세대 항공운항(NexGen) 동향 (A Study on the Trends of the FAA's NextGen)

  • 김유광
    • 항공우주시스템공학회지
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    • 제6권3호
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    • pp.19-23
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    • 2012
  • "The FAA's Next Generation Air Transportation System" is a comprehensive overhaul of U.S National Airspace System to make air travel more convenient and dependable, while ensuring the flight is as safe, secure and hassle-free as possible. At its most basic level, NextGen represents an evolution from a ground-based system of air traffic control to a satellite-based system of air traffic management. This evolution is vital to meeting future demand, and to avoiding gridlock in the sky and at U.S airports. NextGen will open worldwide's skies to continued growth and increased safety while reducing aviation's environmental impact.

Samsung's $4^{th}$ Generation TFT- LCD Production Line Concept

  • Chang, Won-Kie
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2001년도 International Meeting on Information Display
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    • pp.9-12
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    • 2001
  • With the explosive growth of Note-PC and Desktop monitor market, TFT LCD market confronted a entire supply shortage during 1999. Forecasting a more booming stage for the next several years, many TFT-LCD panel manufacturers continue to expand the capacity of their existing plants and also make an additional investment in building new plants. The new investment is concentrated on the $4^{th}$ generation TFT LCD line in order to improve investment efficiency. The set up of the Samsung's Gen 3.5 line progressed with satisfactorily performance using $600{\times}720mm$ glass size. We have continuously reviewed several issues regarding the glass size for our next Gen. 4 line, which leads to adopt $730{\times}920mm$. Due to the continuous enlargement of a substrate size and following difficulty in transferring cassettes, the next line is expected to be the last line that employs "cassette transfer". The layout of the next line will shift from conventional "concentration-type" to "separation-type" configuration for the purpose of reducing transfer distance as well as transfer time. The details will be discussed in this paper.

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A load-bearing structural element with energy dissipation capability under harmonic excitation

  • Pontecorvo, Michael E.;Barbarino, Silvestro;Gandhi, Farhan S.;Bland, Scott;Snyder, Robert;Kudva, Jay;White, Edward V.
    • Advances in aircraft and spacecraft science
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    • 제2권3호
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    • pp.345-365
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    • 2015
  • This paper focuses on the design, fabrication, testing and analysis of a novel load-bearing element with energy dissipation capability. A single element comprises two von-Mises trusses (VMTs), which are sandwiched between two plates and connected to dashpots that stroke as the VMTs cycle between stable equilibrium states. The elements can be assembled in-plane to form a large plate-like structure or stacked with different properties in each layer for improved load-adaptability. Also introduced in the elements are pre-loaded springs (PLSs) that provide high initial stiffness and allow the element to carry a static load even when the VMTs cannot under harmonic disturbance input. Simulations of the system behavior using the Simscape environment show good overall correlation with test data. Good energy dissipation capability is observed over a frequency range from 0.1 Hz to 2 Hz. The test and simulation results show that a two layer prototype, having one soft VMT layer and one stiff VMT layer, can provide good energy dissipation over a decade of variation in harmonic load amplitude, while retaining the ability to carry static load due to the PLSs. The paper discusses how system design parameter changes affect the static load capability and the hysteresis behavior.

Adaptive Q-Algorithm for Multiple Tag Identification in EPCglobal Gen-2 RFID System

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • 제8권3호
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    • pp.307-311
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    • 2010
  • EPCglobal Class-1 Gen-2 protocol has been proposed for UHF-band RFID systems. In Gen-2 standard, Q-algorithm was proposed to select a frame size for the next query round without estimating the number of tags. Therefore, the Q-algorithm has advantage that the reader's algorithm is simpler than other algorithms. However, it is impossible to allocate the optimized frame size. Also, the original Q-algorithm did not define an optimized parameter C for adjusting the frame size. In this paper, we propose an adaptive Q-algorithm with the different parameter $C_c$ and $C_i$ in accordance with the status of reply slot. Simulation results show that the proposed adaptive Q-algorithm outperforms the original Gen-2 Q-algorithm.

Characterization of the performance of the next-generation controller for the BOES CCD

  • Park, Su-Hwan;Yu, Young Sam;Sung, Hyun-Il;Park, Yoon-Ho;Lee, Sang-Min;Bang, Seung-Cheol;Chun, Moo-Young;Seong, Hyeon-Cheol;Kim, Minjin
    • 천문학회보
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    • 제46권2호
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    • pp.76.2-76.2
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    • 2021
  • We present the characterization of the performance of the next-generation controller (SDSU Gen III) for BOAO Echelle Spectrograph CCD (BOES CCD) at the Bohyunsan Optical Astronomy Observatory. The current controller (SDSU Gen II) of the BOES CCD will be upgraded to SDSU Gen III to provide a more stabilized operation. To assess the performance of the new controller (e.g., conversion gain, full well capacity, S/N), we obtain various types of calibration images (e.g., bias, flat, science images of standard stars). Based on those datasets, we find that the overall performance of the new controller is somewhat comparable to that of the old controller if the slow mode is adopted for the readout. This may demonstrate that the new controller can be successfully substituted for the old controller without a substantial loss of performance. However, further analysis with a large dataset obtained in various observational conditions is necessary to confirm our results.

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Adaptive Slot-Count Selection Algorithm based on Tag Replies in EPCglobal Gen-2 RFID System

  • 임인택
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2011년도 추계학술대회
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    • pp.653-655
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    • 2011
  • EPCglobal proposed a Q-algorithm, which is used for selecting a slot-count in the next query round. However, it is impossible to allocate an optimized slot-count because the original Q-algorithm did not define an optimized weight C value. In this paper, we propose an adaptive Q-algorithm, in which we differentiate the weight values with respect to collision and empty slots. The weight values are defined with the identification time as well as the collision probability.

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Optimal Parameter Selection of Q-Algorithm in EPC global Gen-2 RFID System

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • 제7권4호
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    • pp.469-474
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    • 2009
  • Q-algorithm is proposed at EPC global Class-1 Generation-2 RFID systems to determine the frame size of next query round. In Q-algorithm, the reader calculates the frame size without estimating the number of tags. But, it uses only the slot conditions: empty, success, or collision. Therefore, it wastes less computational cost and is simpler than other algorithms. However, the constant parameter C value, which is used for calculating the next frame size, is not optimized. In this paper, we propose the optimized C values of Q-algorithm according to the number of tags within the identification range of reader through a lot of computer simulations.

미국과 유럽의 차세대 회전익 기술 개발 현황 (Next Generation Rotorcraft Technologies in USA and Europe)

  • 오세종;김성환
    • 한국항공우주학회지
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    • 제42권8호
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    • pp.713-721
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    • 2014
  • 현재 유럽과 미국에서는 각각 GRC(Green Rotorcraft) 와 SRW (Subsonic Rotary Wing program) 프로그램을 통하여 차세대 회전익기 개발이 진행 중에 있다. 이들 프로그램의 최종 목적은 현재 사용 중에 있는 단거리 여객기를 일부 대체 할 수 있는 틸트로터 타입의 중/소형 민간 회전익기 개발에 목적을 두고 있다. 또한 이들 틸트 로터의 민간 운영에 운영할 수 있는 안전한 운행을 위하여, 각각 개발 중인 air transport management(ATM) 시스템인 SESAR(Single European Sky ATM Research) 와 NextGen(Next Generation Air Transport System)과 융합하는 기술도 병행되고 있다. 이들 프로그램들은, 최종 목표인 틸트 로터기의 개발이 진행되는 중간 과정으로, 현재 사용되고 있는 헬리콥터의 성능의 향상도 병행하고 있다. 이러한 성능 개발은 좀 더 효율적인 추진기관, 능동 로터 시스템, 내/외부의 소음 감소 등에 중점을 두고 있다. 특히 유럽의 GRC 프로그램에서는 소음, 연료소비율, 배기가스 (CO2, NOx)의 절감 등에 매우 구체적인 목표를 설정하여 기술 개발을 진행 중에 있다.

헬기 운항안전 향상을 위한 북미지역의 개발 동향 (Development Trends of North America to Enhance the Flight Safety of Helicopter)

  • 오경륜;최석;박중용
    • 한국항행학회논문지
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    • 제17권6호
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    • pp.798-803
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    • 2013
  • 본 논문에서는 헬기운항안전 향상을 위한 북미대륙의 활동들을 소개하였다. 북미지역에서는 2009년 기준으로 전세계 민간헬기의 49%가 운용되고 있어, 이 지역에서의 헬기 운항안전을 위한 개발동향은 여타 헬기 운용지역에도 상당한 영향을 미칠 것으로 예상된다. 대규모 헬기가 운용되는 멕시코만의 헬기 운항안전을 위한 개발 사례와 미국 연방항공청(FAA, Federal Aviation Administration)의 NextGen 프로그램 및 국제민간항공기구 (ICAO, International Civil Aviation Organization)의 항공시스템블록업그레이드(ASBU, Aviation System Block Upgrades) 계획 실행을 위한 캐나다 계획 분석을 통해 헬기 관련 인프라 구축 동향 및 향후 헬기 운항안전 증진을 위해 나아갈 바와 기대효과에 대해 정리하였다.

지식기반신경망에서 은닉노드삽입을 이용한 영역이론정련화 (Theory Refinements in Knowledge-based Artificial Neural Networks by Adding Hidden Nodes)

  • 심동희
    • 한국정보처리학회논문지
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    • 제3권7호
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    • pp.1773-1780
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    • 1996
  • 인공지능의 기호적 방법과 수치적 방법을 결합한 지식기반신경망은 다른 기계 학 습모델보다 우수한 성능을 나타내고 있다. 그러나 지식기반신경망은 신경망으로 형성 된 후 동적으로 그 구조를 변경할 수 없어서 영역이론정련화 기능을 갖추지 못하였다. 지식기반신경망의 이러한 단점을 보완하기 위하여 TopGen 알고리즘이 제안되었으나 삽입된 은닉노드를 모두 입력 노드에 연결한 점, 빔탐색을 이용한 등의 문제를 안고 있다. 본 논문에서는 TopGen의 문제점을 해소하기 위하여 은닉 노드를 다음 하위계층 의 노드에 링크 시켰으며, 역추적을 허용한 언덕 오르기를 이용하는 알고리즘을 설계 하였다.

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