• The Bulletin of The Korean Astronomical Society
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• v.25 no.1
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• pp.48-48
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• 2000

• Journal of the Chungcheong Mathematical Society
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• v.16 no.1
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• pp.61-71
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• 2003

We obtain a necessary condition for splitting T-space off a space in terms of cyclic maps, and also obtain a necessary condition for splitting co-T-spaces in terms of cocyclic maps.

• Journal of The Korean Astronomical Society
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• v.29 no.1
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• pp.75-81
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• 1996

We mapped the $^{13}CO$ line in the dark nebula L134 using the 14-m Taeduck radio telescope with a 57 arcsec beam and one beam spacing. The cloud has a spherical shape with an intensity peak ridge extended from the northwest to the southeast directions. The halfwidth and the radial velocity of the lines peak at the region of the cloud center. The radial velocity decreases from the cloud center towards the north and south directions. The integrated line intensity distributions in the space-velocity plane show some structure and a velocity gradient. The $^{13}CO$ and $H_2CO$ clouds and dark clouds are closely related in space in shape, outer boundary, and intensity peak positions. The $^{13}CO$ integrated line intensity is linearly proportional to the visual extinction.

• ETRI Journal
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• v.45 no.2
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• pp.203-212
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• 2023

In this study, we developed a co-located and space-shared multiple-input multiple-output (MIMO) antenna module with a modular design and high integration level. The proposed antenna pair includes a half-wavelength loop antenna and a dipole-type antenna printed on the front and back sides of a compact modular board. Owing to their modal orthogonality, these two independent antenna elements are highly self-isolated and free of additional decoupling components, even though they are assembled at the same location and within the same space. Thus, the proposed antenna is attractive in 5G MIMO systems. Furthermore, the proposed co-located and space-shared MIMO antenna module was employed in a 5G smartphone to verify their radiation and diversity performances. A 12 × 12 MIMO antenna system was simulated and fabricated using the proposed module. Based on the results, the proposed module can be employed in large-scale MIMO antenna systems for current and future terminal devices owing to its high integration, compactness, simple implementation, and inherent isolation.

• Bulletin of the Korean Space Science Society
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• 1995.04a
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• pp.20-20
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• 1995

• The Bulletin of The Korean Astronomical Society
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• v.28 no.1
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• pp.43-43
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• 2003

• The KIPS Transactions:PartB
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• v.8B no.3
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• pp.269-282
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• 2001

최근 웹의 확산과 더불어 제품개발을 위하여 공동작업 구성원들 사이의 정보 공유와 재사용을 지원하는 웹 기반의 공동작업 지원 시스템 개발에 대한 관심이 고조되고 있다. 기업 및 공공기관의 공동작업은 광범위하게 분산되어 있는 경우가 많으며, 여러 작업그룹 내의 구성원은 이러한 환경에서 효과적으로 서로의 정보를 교환하고 공유할 수 있는 작업공간을 필요로 한다. 또한 공동작업의 결과로서 생성된 기술문서의 체계적인 관리 기능과 실시간 의사전달의 기능 등이 함께 제공되는 것이 바람직하다. 본 논문에서는 웹 기반의 공동작업 지원 시스템인 CoWare의 설계와 구현에 대하여 설명한다. CoWare는 통합시스템으로서 CoSpace, CoDocs, CoMail로 명명된 세 개의 관련된 시스템으로 구성된다. CoSpace는 자료의 저장과 공유를 위하여 개인 및 작업그룹을 위한 작업공간을 제공하고, CoDocs는 전자문서의 체계적인 관리를 지원하며, CoMail은 실시간 의사전달의 기능을 제공한다. CoSpace, CoDocs, 그리고 CoMail은 기본적으로 사용자 정보, 사용자 그룹정보, 작업그룹정보의 공유를 통하여 상호 연계되어, 보다 자연스럽고 효율적으로 공동작업을 지원할 수 있다.

• Bulletin of the Korean Space Science Society
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• 1998.10a
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• pp.23.1-23
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• 1998

No Abstract.See Full-text

• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.243-248
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• 2004

We present measurements of interstellar CO absorption lines in the spectra of 7 early-type stars that were observed with the FUSE(Far Ultraviolet Spectroscopic Explore.) Among 54 early-type target stars in the Galactic disk and halo observed with the BBFS(Berkeley Extreme and Far-ultraviolet Spectrometer), we choose 7 program stars (HD 37903, HD 97991, HD 149881, HD 156110, HD 164794, HD 214080 and HD 219188) which have only a single velocity component in the high-resolution optical measurements, in order to avoid line blending. To analyze the CO molecule, we select the E-X (0-0) band at $1076{\AA}$, which has a large oscillate. strength and is not blended with other interstellar absorption lines. We detect the CO absorption lines in three (HD 37903, HD 164794, and HD 214080) out of seven targets, and derive CO column densities for those targets. We also estimated the CO to $H_2$ ratios toward the three stars, based on the previously estimated $H_2$ column densities.

• 제어로봇시스템학회:학술대회논문집
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• 1986.10a
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• pp.68-72
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• 1986

Upper bounds of the perturbed Co-semigroups of the infinite dimensional systems are investigated by using the algebraic Riccati equation(ARE). In the case that the solution P of the ARE is strictly positive, the perturbed semigroups are uniformly bounded. A sufficient condition for the solution P to be strictly positive is provided. The uniform boundedness plays an important role in extending approximately weak stability to weak stability on th whole space. Exponential Stability of the perturbed semigroups is studied by using the Young's inequlity. Some further discussions on the uniform boundedness of the perturbed semigroups are given.