• Journal of Astronomy and Space Sciences
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• v.15 no.2
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• pp.417-425
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• 1998

Monte Carlo analysis is performed for the first acquisition and tracking of the KOMP-SAT spacecrat in GSOC tracking station after separation from Taurus launch vehicle. The error bounds in position and velocity vector in Earth-fixed coordinate system at injection point are assumed based on the previous launch mission. Ten thousands injection orbital elements with normal distribution are generated and propagated for Monte Carlo analysis. The tracking antenna pointing errors at spacecraft rising time and closest approach time at German Space Operations Center(GSOC) Weiheim track-ing station are derived. Then the tracking antenna scanning angles are analyzed for acquisition and tracking of the KOMPSAT signal.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2003.11a
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• pp.51-55
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• 2003

소형 표시창에서 펜과 커서키를 이용한 타겟 포인팅 성능을 비교하기 위하여 두 가지 실험이 수행되었다. 첫 번째 실험에서 우리는 서로 다른 타겟 크기에서 두 가지 입력방법에 의한 참여자의 타겟 포인팅 성능을 조사하였다. 타겟의 크기가 5미리 보다 작을 경우 펜입력이 키를 기본으로 하는 입력보다 더 에러가 많지만 타겟 크기가 5미리일 때 에러율이 키입력과 같은 수준으로 감소한다는 것을 발견했다. 두 번째 실험에서 우리는 타겟의 개수가 미치는 영향을 조사하였다. 그 결과 타겟의 크기가 5미리일 때 타겟의 거리가 3단계의 경로길이를 초과할 경우 펜입력이 키입력보다 더 빨리 타겟을 포인팅할 수 있다는 것을 알았다.

• Journal of Korean Library and Information Science Society
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• v.34 no.3
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• pp.67-92
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• 2003

The purpose of this paper is to review the change of school library in Korea. The writer keeps an eye on the 'School Library Activation Project' initiated by the Ministry of Education. The writer concludes by pointing out some problems of school library in Korea at its present developmental stage.

• Structural Engineering and Mechanics
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• v.27 no.5
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• pp.555-574
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• 2007

Static response of an elastic beam on a two-parameter tensionless foundation is investigated by assuming that the beam is symmetrically subjected to a uniformly distributed load and concentrated edge loads. Governing equations of the problem are obtained and solved by pointing out that a concentrated edge foundation reaction in addition to a continuous foundation reaction along the beam axis in the case of complete contact and a discontinuity in the foundation reactions in the case of partial contact come into being as a direct result of the two-parameter foundation model. The numerical solution of the complete contact problem is straightforward. However, it is shown that the problem displays a highly non-linear character when the beam lifts off from the foundation. Numerical treatment of the governing equations is accomplished by adopting an iterative process to establish the contact length. Results are presented in figures to demonstrate the linear and non-linear behavior of the beam-foundation system for various values of the parameters of the problem comparatively.

• Journal of Astronomy and Space Sciences
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• v.22 no.3
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• pp.243-248
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• 2005

NORAD Two Line Element (TLE) is very useful to simplify the ground station antenna pointing and mission operations. When a satellite operations facility has the capability to determine NORAD type TLE which is independent of NORAD, it is important to analyze the applicable tracking data arcs for obtaining the best possible orbit. The applicable tracking data arcs for NORAD independent TLE orbit determination of the KOMPSAT-1 using GPS navigation solutions was analyzed for the best possible orbit determination and propagation results. Data spans of the GPS navigation solutions from 1 day to 5 days were used for TLE orbit determination and the results were used as Initial orbit for SGP4 orbit propagation. The operational orbit determination results using KOMPSAT-1 Mission Analysis and Planning System(MAPS) were used as references for the comparisons. The best-matched orbit determination was obtained when 3 days of GPS navigation solutions were used. The resulting 4 days of orbit propagation results were within 2 km of the KOMPSAI-1 MAPS results.

• Proceedings of the Korea Multimedia Society Conference
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• 2001.11a
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• pp.205-209
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• 2001

3D 가상판정에서의 네비게이션 기법은 공간에 대한 참여자의 몰입감과 사실감에 결정적인 영향을 미치는 매우 중요한 요소이다. 네비게이션 분야에 대한 기존의 연구는 주로 강력한 하드웨어를 기반으로 하는 몰입형 가상현실 분야 위주로 진행되어 왔다. 최근에는 인터넷을 기반으로 하는 비 몰입형 가상환경 분야에 대한 관심이 고조되고 있으나 참여자가 인지하는 3D-2D간의 공간적 불일치 문제를 해결해야 하는 어려움을 가지고 있다. 따라서 본 논문에서는 비 몰입형 가상환경에서 참여자의 3D 공간에 대한 인지적인 문제를 해결해 굴 수 있는 네비게이션 기법으로서, 포인팅에 기반 한 3D-2D간의 매핑, 이동 방향이나 목표지점을 제시하는 시각 피드백, 이동 중 참여자 시점 동시변경 기능들을 제안한다 제안된 기법은 3D 가상환경에서 일반 참여자의 네비게이션을 매우 효과적으로 지원할 수 있음을 확인하였다.

• Computers and Concrete
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• v.5 no.6
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• pp.545-558
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• 2008

The corrosion of RC structures demonstrates very complicated forms of deterioration intermingled together but all pointing to a decrease in the durability of RC structures due to the corrosion of reinforcing bars. Until now, nondestructive techniques, such as half-cell potential and polarization resistance, have been widely available in the world. The former provides information on the probability of corrosion while the latter is associated with information concerning corrosion rates. Inversion by the boundary element method (IBEM) was developed for considering concrete resistivity. The applicability of the procedure was examined through a numerical analysis and electrolytic tests for RC slabs. A distribution in such concrete resistivity is relatively inhomogeneous including cracks on the surface of slabs. Regarding cracks in concrete, the relative coefficient of concrete resistance was introduced to perform its analysis. Further, the procedure will be developed to identify the corroded region visually using 3-D VRML.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.445-453
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• 2016

Epidermal growth factor receptors (EGFRs/HERs) and downstream signaling pathways have been implicated in the pathogenesis of several malignancies including breast cancer and its resistance to treatment with chemotherapeutic drugs. Consequently, several monoclonal antibodies as well as small molecule inhibitors targeting these pathways have emerged as therapeutic tools in the recent past. However, studies have shown that utilizing these molecules in combination with chemotherapy has yielded only limited success. This review describes the current understanding of EGFRs/HERs and associated signaling pathways in relation to development of breast cancer and responses to various cancer treatments in the hope of pointing to improved prevention, diagnosis and treatment. Also, we review the role of breast cancer stem cells (BCSCs) in disease and the potential to target these cells.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9567-9574
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• 2014

${\beta}$-Blockers have been one of the most widely used and versatile drugs for the past half a century. A new potential for their use as anti-cancer drugs has emerged in the past few years. Various retrospective case control studies have been suggestive that use of ${\beta}$-blockers before the diagnosis of cancer could have preventive and protective effects against non-small cell lung carcinoma, melanoma, and breast, pancreatic and prostate cancers. Experimental and clinical observations are still inconclusive with some inconsistent findings. However, indications are pointing toward a positive role of some ${\beta}$-blockers against certain forms of cancers. This mini review is an effort to present the up to date published results of case-control studies and experimental findings.

• Journal of Korean Neurosurgical Society
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• v.38 no.2
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• pp.151-154
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• 2005

A 43-year-old woman was admitted with the chief complaint of progressive visual disturbance and her brain radiological studies disclosed well demarcated tumor at tuberculum sellae area and bilateral mirror image paraclinoid internal carotid artery saccular aneurysms. A larger left side aneurysm was pointing medialy and almost encased by the tumor. Although a brain tumor and intracranial aneurysm can be simultaneously treated by surgery, the high risk of intra-operative aneurysm rupture should be considered. Therefore, the author secondly performed tumor resection after the endovascular embolization of the aneurysm which was embedding the tumor using a Guglielmi detachable coil. After successful treatment of the patient with tuberculum sellae meningioma associated with bilateral mirror image paraclinoid aneurysms using endovascular and surgical techniques, the authors present the case with a review of the related literatures.