• Title/Summary/Keyword: sun

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A Study on the Utilization of Cheonan-river in view of Urbam Regeneration (도심재생의 측면에서 바라 본 천안천 활용실태조사)

  • Sung, Min-Ho;Kim, Dae-Jin;Kim, En-Bong;Lee, Hee-Won
    • Proceedings of the KAIS Fall Conference
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    • 2011.12b
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    • pp.453-456
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    • 2011
  • 전 세계적으로 도시수변공간 개발이 이슈화 되고 있는 요즘. 우리나라에서도 급속한 경제 발전에 따라 회손 되어버린 하천들의 정비사업이 활성화 되고 있다. 이에 본 연구에서는 도시수변공간과 도시재생에 대해 조사하여 이해하고 그 사례를 들어 어떠한 방법들로 개발되었는지 살펴본 뒤, 천안천의 형장조사를 통해 상류, 중류, 하류로 나누어 각각의 구역이 어떠한 방식으로 개발되었으며 현재 이용자들에게 어떻게 활용되는지를 파악하였다.

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A Comparative Study on Usage Condition of Cheonancheon and Wonseongcheon (천안천과 원성천의 현황 및 이용실태 비교조사)

  • Jeon, Soo-Jin;Choi, Ye-Sl;Jo, Jung-Mi;Lee, Hee-Won
    • Proceedings of the KAIS Fall Conference
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    • 2011.12b
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    • pp.449-452
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    • 2011
  • 본 연구에서는 도심 속 생태하천으로 탈바꿈하기 위한 '자연형 하천정화사업' 중 천안시의 하천정비사업과 관련하여 최근 집중 개발된 천안천과 원성천의 이용실태에 관하여 실증적 조사를 시행하였다. 천안천과 원성천의 현황을 비교 분석하여 비슷한 시기에 개발되었음에도 불구하고 원성천이 천안천에 비하여 보다 자연형에 가깝게 발전된 요인을 알아보고자 하였다.

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Calibration of Low-cost Inertia Navigation System with Sun Line of Sight Vector (태양시선벡터를 이용한 저가 관성항법시스템의 보정)

  • Jang, Se-Ah;Choi, Kee-Young
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.8
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    • pp.774-778
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    • 2008
  • The inaccuracy of inertial sensors used in low cost IMU's limits the usage to ARS, at best. Sensor fusion technologies are widely used to overcome this problem. GPS is the most popular secondary sensor, but GPS alone cannot fully compensate the IMU errors in the initial alignment process and rectilinear flights. This paper presents a new concept of aiding the low cost IMU with the sun line of sight vector. The simulation and experimental results in this paper proves that aiding of INS/GPS with the sun line of sight vector increases the observability and improves accuracy remarkably.

Validation and Development of Artificial Sky Dome Facilities with a Heliodon (인공 천공돔과 헬리오돈의 개발 및 성능실험 사례 연구)

  • Kim, Jeong-Tai;Kim, Gon
    • KIEAE Journal
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    • v.3 no.1
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    • pp.21-29
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    • 2003
  • Scale model measurements should be conducted under an actual sky or in a simulated sky where conditions can be held constant. A number of successful attempts have been made to develop artificial sky domes with man-made sun emulators. With reference to formerly-developed examples, sky simulator facility has recently been activated in oder to provide desirable sky conditions for teaching and studies. The structure is a 6m-diameter dome and promises to set various condition for energy related and lighting research activities. The sky dome is also equipped a heliodon, the tilt table, to facilitate additive direct sun impact under clear skies. Shading studies, using scale models with the heliodon, reveal how a building's design blocks or permits light's passage to the interior; solar access studies, and tests of the reflection and transmittance characteristics of new daylighting technologies. The design and construction specification and the initial operating experience with a building configuration are reported.

Properties of transient horizontal magnetic fields and their implication to the origin of quiet-Sun magnetism

  • Ishikawa, Ryohko
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.1
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    • pp.84.1-84.1
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    • 2012
  • Recent spectropolarimetric observations with high spatial resolution and high polarization sensitivity have provided us with new insight to better understand the quiet-Sun magnetism. This talk is concerned with the ubiquitous transient horizontal magnetic fields in the quiet-Sun, as revealed by the Solar Optical Telescope (SOT) on board Hinode satellite. Exploiting the SOT data with careful treatment of photon noise, we reveal the enigmatic properties of these horizontal magnetic fields such as lifetime, size, position in terms of granular structure, occurrence rate, three-dimensional structure, total magnetic flux, field strength distribution, relationship with the meso- and super-granulations and so on. Based on these observational consequences, we conjecture that the local dynamo process, which takes place in a relatively shallow layer with the granular size, produces these transient horizontal magnetic fields and that these horizontal magnetic fields contribute to the considerable amount of quiet-Sun magnetic fields. We also estimate the magnetic energy flux carried by these horizontal magnetic fields based on the statistical data, and find that the total magnetic energy is comparable to the total chromospheric and coronal energy loss, implying their important role for the chromospheric heating and dynamism.

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A Study on the Collector Characteristics of Evacuated Double Glass Tube by Artificial Sun (인공태양에 의한 이중 진공 유리관의 집열특성에 관한 연구)

  • Nam, Yong-Han;Shin, Jae-Ho;Mo, Joung-Gun;Chung, Han-Shik;Jeong, Hyo-Min;Suh, Jeong-Se
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.1542-1547
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    • 2003
  • This paper represents the solar collector performance with type of an evacuate double glass, and a copper tube was installed in center of collector to get a solar thermal energy. The one module of solar collector and artificial sun were used in this experiment The distance between artificial sun and solar collector was fixed at 0.5m, and this experimental condition was focused on winter season. The experiments were carried out. three times for getting a accurate data and the heat amount of one module evacuate d solar collector was estimated at out. 48 kcal/hr.

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A New Scheme for Watermarking Engineering Graph

  • Zhanchuan, Cai;Wei, Sun;Changzhen, Xiong;Dongxu, Qi
    • International Journal of CAD/CAM
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    • v.6 no.1
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    • pp.99-104
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    • 2006
  • Engineering graph plays an important role in design and manufacture, such as architecture, machinery, manufacture, military. However, almost no persons consider the security and copyright of two-dimensional engineering graph. A novel method for two-dimensional engineering graph watermark based U system is proposed in this paper. Watermarks generated by this technique can be successfully extracted even after rotation, translation and scaling transform.

COMS METEOROLOGICAL IMAGER SPACE LOOK SIDE SELECTION ALGORITHM

  • Park, Bong-Kyu;Lee, Sang-Cherl;Yang, Koon-Ho
    • Proceedings of the KSRS Conference
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    • 2008.10a
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    • pp.100-103
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    • 2008
  • COMS(Communication, Ocean and Meteorological Satellite) has multiple payloads; Meteorological Image(MI), Ocean Color Imager(GOCI) and Ka-band communication payloads. MI has 4 IR and 1 visible channel. In order to improve the quality of IR image, two calibration sources are used; black body image and cold space look data. In case of COMS, the space look is performed at 10.4 degree away from the nadir in east/west direction. During space look, SUN or moon intrusions are strictly forbidden, because it would degrade the quality of collected IR channel calibration data. Therefore we shall pay attention to select space look side depending on SUN and moon location. This paper proposes and discusses a simple and complete space look side selection logic based on SUN and moon intrusion event file. Computer simulation has been performed to analyze the performance of the proposed algorithm in term of east/west angular distance between space look position and hazardous intrusion sources; SUN and moon.

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Development of the Phase Difference Controller of Ultrasonic Motor using PLSI method (PLSI를 이용한 초음파 모터 위상차 제어기 개발)

  • Kim, Dong-Ok;Lee, Kam-Youn;Kim, Won-Bae;Choi, Han-Soo;Kim, Young-Dong
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.182-185
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    • 1995
  • The travelling ultrasonic motor(USM) has good some characteristics over conventional servo motors such as compact size, light weight, silent moton, high torque and high speed response. The USM is driven by 2-phase AC electricity. By adjusting the phase difference of the motor power we control rotation, speed and torque of USM. In this paper, we propose design method using PLSI(programmable Large Scale Integration) of USM controller to adjust the phase difference of the motor power. As compared the previous, the new controller has some advantage that high speed, predictable performance, low power and so on.

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Ganglion Cyst of the Posterior Cruciate Ligament -Two Cases Report- (슬관절 후방십자인대에 발생한 결절종 -증례보고-)

  • Cho, Jae-Yeong;Yoo, Hyun-Jong;Lee, Eui-Hyong;Lee, Ju-Youn
    • Journal of the Korean Arthroscopy Society
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    • v.2 no.2
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    • pp.189-192
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    • 1998
  • Ganglion cysts have been described in all joints. In the knee, although the finding of meniscal degenerative cysts is fairly common, a few cases have been reported concerning ganglion cysts of anterior cruciate ligament. However, ganglion cysts of posterior cruciate ligament are quite rare. We experienced two cases of ganglion cyst in the posterior cruciate ligament, which were treated successfully with arthroscopic debridement.

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