• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.4
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• pp.53-59
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• 2003

Strain Energy Hinge(SEH) has been used in Korea Multi-purpose Satellite(KOMPSAT) series to deploy the solar panel due to the good record of reliability. However, when it reached a desired deployment position, a large buckling force is applied to the main body. This may cause structural damage and also affect control of the satellite. Therefore, reliable dynamic analysis for the deployment system is required at a design stage. Moreover, various mission of a satellite has made the size of solar panels got bigger, so elastic effect has to be considered seriously to get more precise analysis results. In this paper, a dynamic analysis method to predict the deployment is verified by KOMPSAT-2 deployment test.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.38-45
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• 2003

This research is concerned with the dynamic modeling of the multi-purpose satellite with deployable solar arrays equipped with strain energy hinges(SEH). To this end, we proposed the use of the equivalent torsional spring for the SEH and derived the equations of motion assuming that the satellite and solar arrays are being rigid. We also considered the effect of the support string for the ground experiment model, which has been observed as a critical factor affecting the deployment in the ground experiments. From the numerical simulation results, it is found that solar arrays are deployed in a similar pattern but the hub motions are different because of the support strings. It was concluded that the non-gravity deployment of the solar arrays can be approximately simulated by the ground experimental facility. The effects of the support string are also investigated by varying the length of the string. It was found that the current length of the string is adequate for the ground experiment. Ground experimental results will follow.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.12
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• pp.1007-1012
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• 2017

In this study, we performed the deployment test of shape memory polymer specimens for space antenna design. Poly(cyclootene) was cross-linked by dicumyl peroxide to make a PCO shape memory polymer. A miniature specimen with 120 mm diameter for a deployable antenna was fabricated with the PCO shape memory polymer. To investigate the deployment performance, the folded specimen as a temporary shape was heated by two heaters to the $15^{\circ}C$ higher temperature than the glass transition temperature of shape memory polymer. Firstly, the specimen was installed horizontally and tested. The deploying motion was captured by a digital camera and analyzed by a Tracker program. To reduce the effects of gravity, the specimen was installed vertically and tested again. The deployment performance of a shape memory polymer was investigated by comparing the results of horizontal and vertical installation tests.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.8
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• pp.603-609
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• 2017

In the deployable solid surface antennas, the effects on the performances of antenna due to the structural errors that occur during the deployment are analyzed. The deployable solid surface antennas employed in a satellite are launched in folded configuration and those are deployed in the space environment, and the effects on the antenna performance are calculated depending on the type of surface errors. When the deviation error occurs in one panel, the degradation of performance appears in the side where the incomplete deployment of panel occurs. By assuming that the panel error distribution is in cosine function, the effect of errors are calculated and analyzed with regard to the types and the magnitude of the error. If the antena panel error is uniform, the gain is reduced and pattern is symmetric. For the panel error of cosine 1 or 3 cycle, the main lobe tilts while the pattern is symmetric and the gain reduces for 2 or 4 cycle error.

• Journal of Aerospace System Engineering
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• v.13 no.5
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• pp.94-101
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• 2019

The dynamic characteristics of the composite reflector panels are numerically and experimentally investigated. A dynamics model of the panel is analytically developed based on a deployment mechanism of the antenna. The deployment is passively activated using elastic energy of a spring with two rotational degrees of freedom. Using the flexible multi-body dynamic analysis ADAMS, dynamic behavior of the panels such as velocities, deformations, as well as reaction forces during the deployment, are investigated in the gravity and zero-gravity cases. The reflector panel is manufactured using carbon fiber reinforced plastics (CFRPs) and its deployment characteristics are experimentally observed using a zero-gravity deployment test. The impact response and vibration problems that occur during deployment of the antenna panel have been identified and reliably deployed using dampers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.10
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• pp.705-711
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• 2019

Dynamic behaviors of the deployable composite reflector antenna are numerically and experimentally investigated. Equations of the motion are formalized using Kane's equation by considering multibody systems with two degrees of freedom such as folding and twisting angles. To interpret structural deformations of the reflector antenna, the composite reflector is modeled using a beam model with the FSDT(First-order Shear Deformation Theory). To determine design parameters such as a torsional spring stiffness and a damping coefficient depending on deployment duration, an inverted pendulum model is simply applied. Based on the determined parameters, dynamic characteristics of the deployable reflector are investigated. In addition, its results are verified and compared through deployment tests using a gravity compensation device.

• 프린팅코리아
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• v.14 no.9
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• pp.96-97
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• 2015

지식정보화와 인터넷이라는 용어가 낯설던 1990년대부터 학술지 데이터베이스 서비스 사업을 기초로 디지털 인쇄사업을 펼쳐왔던 한국학술정보(주)(대표이사 채종준)는 디지털 인쇄 보급 초창기부터 활발한 비즈니스를 전개해온 것으로 유명하다. 지난 2004년부터 본격적인 출판 사업을 전개해 매년 500여종의 단행본을 출간하고 있으며, 지난 5월에는 본사와 서울 충무로 북토리에 리코 프로 C7100SX 디지털 인쇄기를 도입해 부가가치 높은 POD 비즈니스를 전개하고 있다.

• Vending industry
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• v.8 no.3
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• pp.22-23
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• 2008

신선한 계란을 파는 자동판매기가 등장했다. 그동안 자판기 시장에 있어서는 계란을 반숙 완숙으로 조리해 판매하는 제품은 있었어도 계란을 팩으로 해 직접 판매하는 제품은 국내 최초이다. 이 제품을 전개하는 곳은 경기도 광주의 다한영농법인이라는 계란 생산 공급공체. 이 업체는 자판기를 통한 무인유통에 관심을 갖고 DK벤딩과 제휴를 통해 계란자판기를 생산 받아 시장 전개에 나섰다. 새로운 컨셉의 계란자판기가 과연 시장 인기를 끌 수 있을까?

• Satellite Communications and Space Industry
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• v.8 no.1 s.18
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• pp.138-151
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• 2000

본 원고는 ITS 구축에 따른 정보통신의 역할, 통신망 접속구조와 전송규격, 표준화 활동과 서비스 요구사항을 해석하고 국내의 ITS전개와 구축현황을 조사하여 정리하였다. 그리고 차세대 ITS 시스템의 전개와 무선 패킷 통신기술의 개발의 필요성과 ITS 접근전략의 제약요인을 기술하였다.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.61-66
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• 1995

이 논문의 목적은 육방형 핵연료집합체로 구성된 3차원 노심을 해석하기 위한 다항식전개법을 개발하는 것이다. 이를 위해 3차원 육방형 핵연료 집합체를 6개의 3차원 프리즘노드로 분할하였다. 그리고 각 꼭지점에서의 점중성자속, 프리즘 각면의 면중성자속과 노드평균중성자속을 미지변수로 하여 다항식전개법에 의해 프리즘노드내의 중성자속분포를 근사하였다. 각 중성자속간의 관계식으로서 프리즘노드내에서의 노달중성자평형식, 두 노드사이의 면에서의 중성자류 연속관계식, 각 꼭지점에서의 중성자누설평형식을 사용하였다. 다항식전개법은 해석함수 전개법에 비해 약 3배정도 빠르며 4군확산방정식에도 훌륭이 적용되었다. 그리고 VVBR-1000 3차원 벤치마크 문제에서 최대출력오차 2.6%, VVER-440 3차원 벤치마크 문제에서 12 평면과 24평면으로 나눈 경우 각각 최대출력오차 15%와 6.6%, SNR 3차원 문제에서 8 평면과 16 평면으로 나눈 경우 각각 최대오차 5.4%와 2,6%를 보였다.