• Title/Summary/Keyword: artificial source

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Heat Source Identification Technique of Aircraft and Flare using 2-color Detectable Infrared Sensors (복수 대역 감지 적외선 센서를 이용한 항공기와 플레어의 열원 식별 기술)

  • Lee, Dong-Si;Lee, Kee-Keun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.7
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    • pp.1031-1039
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    • 2015
  • Present guided missiles are equipped with infrared seeker to find the infrared sources radiating from target plane and then chase, which results in an improvement of the hitting success rate when in striking target objects. To interrupt the chases from the guided missile, the target plane spreads the flare, avoiding the missile attracts. Our research is to develop a 2-color infrared identification technique to discern the flare and real thermal source from target plane. Considering flare radiation properties and EM atmosphere transmission rates, two channels were selected, in which main channel (MC) was in a range of 3.7 μm∼4.8 μm and auxiliary channel (AC) in 1.7 μm∼2.3 μm. A 2500K heat source was used for an artificial flare source, while a 570K heat source was utilized for airplane infrared source in experimental testing. Two infrared sensors detectable only at each chanel were employed in order to measure the voltage ratio from two channels, identifying the flare and real target plane via comparison the voltage ratio. Several experimental conditions were imported in order to prove that our proposed 2-color infrared identification technique is very efficient way to discern heat sources from aircraft and flare, demonstrating that our proposed technique is very promising means for our force’s InfraRed Counter Counter Measure (IRCCM) in order to countermeasure opposite force’s InfraRed Counter Measures (IRCM).

Estimation of Source parameters of South Korean Earthquakes (국내 지진의 지진원 변수 추정)

  • 이전희
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 2000.04a
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    • pp.28-35
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    • 2000
  • The quality factor and the seismic source parameters such as the $\chi$ corner frequency and the stress drop were estimated from the small-to-medium instrumental earthquake data in south Korea. The Q facter with 95% confidence level ranges from 1519 to 2158. The regression equation of $\chi$in terms of epicentral distance R, is obtained as $\chi$=0.006717+0.00015R. And the stress drop is estimated as 50 bar which is similar to the previous results carried out by independent researchers. Artificial ground motions were simulated using the estimated earthquake parameter values and compared with real earthquake, The simulated response spectrum is very similar to real one.

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A Study on the Architectural Expression of the light Appeared in the Works of Le Corbusier (르 꼬르뷔제 건축에 나타난 빛의 건축적 표현에 관한 연구)

  • Kim, Chang-Sung
    • KIEAE Journal
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    • v.12 no.4
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    • pp.71-76
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    • 2012
  • The light is one of the most important factors in architectural design. Especially, natural light is the valuable source of illumination that can be utilized for better indoor environment. Compared to artificial light, it is a sustainable energy source without the cost of electric energy and offers a more natural feeling to residents stayed in buildings. Natural light also creates light and shadow in building. It enables people to perceive the depth of space. Many architects have tried to suggest various technologies to create optimum indoor environment by using the natural light. Therefore, this paper tried to examine the works of Le Corbusier and to analyze how to control the light in his works and apply it to his design. It will help to know how he created different characteristics to spaces by using natural light.

A neural network based sensor modeling for 6-DOF motions of objects

  • Park, Won-Shik;Hyungsuck Cho
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.97.5-97
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    • 2002
  • A sensor modeling via artificial neural network is presented in this paper. The optical sensor has been designed to treasure absolute 3-dimensional positions and orientations of objects in 6-DOF. The method utilizes a triangular pyramidal mirror having an equilateral cross-sectional shape referred as 3-facet mirror. The mirror has three lateral reflective surfaces inclined 45 degrees to its bottom surface. The 3-facet mirror is mounted on the object whose 6-DOF motion is to be measured. As optical components, a He-Ne laser source and three position-sensitive detectors(PSD) are used. The laser beam is emitted from the He-Ne laser source located at the upright position and vertically incident o...

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Exploration of a Light Shelf System for Multi-Layered Vegetable Cultivation (자연광 다층 작물재배를 위한 광선반 시스템에 관한 연구)

  • Jang, Seong-Teak;Chang, Seong-Ju
    • KIEAE Journal
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    • v.13 no.2
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    • pp.61-66
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    • 2013
  • This study is to eliminate the need for conventional high density plant factory's artificial light source such as LED to reduce the initial investment of the light source installation as well as the operation cost. Use of solar light could enhance the quality of the vegetables similar to those grown in the natural environment. Provision of solar light into the multilayer vegetable cultivation facilities and collecting maximum and sustainable sunlight without too much loss by tracing solar path and properly distributing it through careful control during daytime are crucial for realizing the investigated rooftop light shelf system for multi-layered vegetable cultivation. In this study, we developed an innovative way of effectively allocating sunlight inside even to otherwise shaded zone of a multi-layer vegetable cultivation facility. To prove the effectiveness of the system's sunlight collection and distribution capability, both simulation and experiment in Daejeon are performed and the outcome is analyzed.

Designing of efficient super-wide bandwidth extension system using enhanced parameter estimation in time domain (시간 영역에서 개선된 파라미터 추론을 통한 효율적인 초광대역 확장 시스템 설계)

  • Jeon, Jong-jeon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2018.10a
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    • pp.431-433
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    • 2018
  • This paper proposes the system that offer super-wideband speech which is made by artificial bandwidth extension technique using wideband speech signal in time-domain. wideband excitation signal and line spectrum pair(LSP) are extracted based on source-filter model in time-domain. Two parameters are extended by each bandwidth extension algorithms, and then, super-wideband speech parameters are estimated. and synthesized. Subjective test shows super-wideband speech is better speech quality than wideband speech signal.

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Multilevel acceleration of scattering-source iterations with application to electron transport

  • Drumm, Clif;Fan, Wesley
    • Nuclear Engineering and Technology
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    • v.49 no.6
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    • pp.1114-1124
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    • 2017
  • Acceleration/preconditioning strategies available in the SCEPTRE radiation transport code are described. A flexible transport synthetic acceleration (TSA) algorithm that uses a low-order discrete-ordinates ($S_N$) or spherical-harmonics ($P_N$) solve to accelerate convergence of a high-order $S_N$ source-iteration (SI) solve is described. Convergence of the low-order solves can be further accelerated by applying off-the-shelf incomplete-factorization or algebraic-multigrid methods. Also available is an algorithm that uses a generalized minimum residual (GMRES) iterative method rather than SI for convergence, using a parallel sweep-based solver to build up a Krylov subspace. TSA has been applied as a preconditioner to accelerate the convergence of the GMRES iterations. The methods are applied to several problems involving electron transport and problems with artificial cross sections with large scattering ratios. These methods were compared and evaluated by considering material discontinuities and scattering anisotropy. Observed accelerations obtained are highly problem dependent, but speedup factors around 10 have been observed in typical applications.

Growth of plug seedlings raised under fluorescent lamps as artificial light source for close illumination (근접조명용 인공광원으로 형광등하에서 육묘된 플러그묘의 생장 특성)

  • 김용현
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1998.10a
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    • pp.47-54
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    • 1998
  • 인공광형 식물공장의 광원으로는 고압나트륨등, 메탈할라이드등, 형광등이 주로 사용되고 있다. 고압나트륨등과 메탈할라이드등은 램프효율은 높으나 각각 청색광 또는 적색광이 부족하여 식물공장의 근접 조명용 단독 광원으로서는 부적합하다. 형광등은 고압나트륨등과 같은 고휘도 방전등에 비해서 광속은 낮으나 광이용효율이 높기 때문에 조직배양묘의 광원으로 널리 사용되고 있다. (중략)

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Review of measurement of impact sound improvement for light-weight floor (경량 바닥구조의 바닥충격음 저감량 실험실 측정방법 고찰)

  • Jang, Gil-Soo;Jung, Kwang-Yong;Kim, Sun-Woo
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.950-955
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    • 2002
  • ISO 140-11 specifies a method for measuring the acoustic properties of floor coverings from the view-point of reducing impact sound transmission. This test method is limited to the specification of procedures for the physical measurement of sound originating from an artificial impact source under laboratory conditions. In this study, ISO 140-11 was reviewed to applicable to domestic floor coverings installed on lightweight floors.

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Study on Development & Implementation of Online Generator Frequency Response Test (On-line 발전기 주파수응답시험 개발 및 적용에 관한 연구)

  • Oh, Chang-Soo;Kwak, Wol-Hwan
    • Proceedings of the KIEE Conference
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    • 2006.07a
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    • pp.48-49
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    • 2006
  • Recently, Importance of Generator's Active/Reactive Power Control Capability is highly emphasized for prevention of Large Blackout. Especially, Generator's frequency Response Capability is important to the Power System Frequency Stability. This paper deals with the Development & Implementation of Each Generator Frequency Response Capability Test via the Injection of Artificial Frequency to the Online Generator. Actual On-line Generator's frequency Response Test was successfully implemented to 13 Generator having various fuel source.

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