• 항공우주기술
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• 제7권1호
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• pp.223-228
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• 2008

본 논문에서는 아리랑위성 2호의 영상촬영 계획 절차를 살펴보고, 각 단계에서 발생할 수 있는 궤도예측 오차를 분석하였다. 이를 위해 영상촬영 계획을 수립하는 PSS와 명령계획을 작성하는 MAPS에서 각각 계산된 자세정보를 상호 비교하여 궤도예측 오차의 원인을 규명하였다. 또한, 아리랑위성 2호의 실제 영상자료를 이용하여 촬영된 영상의 중심점과 미리 계획된 목표지점 사이의 이탈거리인 촬영 지향오차를 계산하였다. 영상촬영 계획은 실제 촬영일보다 이전에 수행되어 궤도예측 오차를 어느 정도 포함하게 되므로, 영상촬영 계획 시 일정한 Margin을 적용해야 할 것으로 판단된다.

• 천문학회보
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• 제46권2호
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• pp.71.3-72
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• 2021

The Intensive Monitoring Survey of Nearby Galaxies (IMSNG) is a high cadence observation program monitoring nearby galaxies at < 50 Mpc with high probabilities of hosting supernovae (SNe). The current number of main IMSNG targets is 60, but with new wide-field facilities joining IMSNG, there is a possibility of increasing the likelihood of catching the early light curves of SNe among galaxies in the vicinity of the main targets. To test the feasibility of the expansion of the sample galaxies, we examine how much the probability of catching SNe increases by adjusting the field of view of the RASA36 telescope which is one of the IMSNG facilities with a large field of view of 6.25 deg2. We calculate supernova rates (SNRs) of galaxies within the FoV that contains main IMSNG galaxies from the stellar mass and star formation rate of the galaxies. Based on the SNRs of these galaxies, we find the best pointing of the telescope towards the highest SNR region. As a result, we present improved total SNR, with respect to the ordinary pointing on average where the IMSNG main target is placed at the center of FoV. The actual observation should be followed to test the effect of this strategy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 정보 및 제어부문
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• pp.632-634
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• 2005

In this paper, The Frenet-Serret formula of classical geometric curve theory with the concept of a missile pointing velocity vector are used to analyze and design a missile guidance law. The capture capability of this guidance law is qualitatively studied by comparing the rotations of the velocity vectors of missile and target relative to the line of sight vector. when fuzzy Table look-up theory applied in target-missile distance & angle displacement, this research. It's performance is better then classical research.

• 한국군사과학기술학회지
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• 제11권3호
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• pp.50-57
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• 2008

A telemetry ground station has a highly directional, parabolic tracking antenna to receive a weak telemetry signal from a target at a distance. The tracking antenna with narrow beam-width normally uses the auto-track method for the target tracking. This paper presents several issues in the auto-track method and introduces a new tracking method using Self-Slaving technique. Self-Slaving means that the tracking antenna is slaved to not data measured by RADAR but GPS/INS informations received by the telemetry system for pointing. The Self-Slaving method shows good performance in comparison with auto-track method.

• 전자공학회논문지S
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• 제35S권5호
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• pp.35-41
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• 1998

This paper presents a decoupling controller of the missile seeker scan loop with a spin-stabilized platform. A precise seeker motion with respect to the scan command is essential for the higher acquisition probability of the target. As the seeker scan loop is a deeply cross-coupled two input two output system, an accurate pointing or scanning for each axis to the target is very difficult, even though provided with the help of a high performance controller. When a decoupling control is applied to the seeker scan loop, the cross-coupling between two axes can be reduced to a remarkable amount. As a low order of controller is required for the real time operation, a PI controller with decoupling filter is suggested and compared with other controllers. A linearized dynamic model of seeker scan loop is used and validated through the comparison of experimental results of step responses.

• International Journal of Precision Engineering and Manufacturing
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• 제7권2호
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• pp.41-45
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• 2006

This paper deals with human spatial cognition using visual and auditory stimulation. More specially, this investigation is to observe the relationship between the head and the eye motor system for the localization of visual target direction in space and to try to describe what is the role of right-side versus left-side pinna. In the experiment of visual stimulation, nineteen red LEDs (Luminescent Diodes, Brightness: $210\;cd/^2$) arrayed in the horizontal plane of the surrounding panel are used. Here the LEDs are located 10 degrees apart from each other. Physiological parameters such as EOG (Electro-Oculography), head movement, and their synergic control are measured by BIOPAC system and 3SPACE FASTRAK. In the experiment of auditory stimulation, one side of the pinna function was distorted intentionally by inserting a short tube in the ear canal. The localization error caused by right and left side pinna distortion was investigated as well. Since a laser pointer showed much less error (0.5%) in localizing target position than FASTRAK (30%) that has been generally used, a laser pointer was used for the pointing task. It was found that harmonic components were not essential for auditory target localization. However, non-harmonic nearby frequency components was found to be more important in localizing the target direction of sound. We have found that the right pinna carries out one of the most important functions in localizing target direction and pure tone with only one frequency component is confusing to be localized. It was also found that the latency time is shorter in self moved tracking (SMT) than eye alone tracking (EAT) and eye hand tracking (EHT). These results can be used in further study on the characterization of human spatial cognition.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1241-1245
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• 2014

Cinobufacin is used clinically to treat patients with many solid malignant tumors. However, the mechanisms underlying action remain to be detailed. Our study focused on miRNAs involved in cinobufacin inhibition of GC cell proliferation. miRNA microarray analysis and real time PCR identified miR-494 as a significant cinobufacin-associated miRNA. In vivo, ectopic expression of miR-494 inhibited the proliferation and induced apoptosis of BGC-823 cells on CCK-8 and flow cytometry analysis. Further study verified BAG-1 (anti-apoptosis gene) to bea target of miR-494 by luciferase reporter assay and Western blotting. In summary, our study demonstrated that cinobufacin may inhibit the proliferation and promote the apoptosis of BGC-823 cells. Cinobufacin-associated miR-494 may indirectly be involved in cell proliferation and apoptosis by targeting BAG-1, pointing to use as a potential molecular target of cinobufacin in gastric cancer therapy.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2003년도 추계학술대회 논문집
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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.

• Asian Pacific Journal of Cancer Prevention
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• 제17권2호
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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.

• 한국전자파학회논문지
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• 제22권3호
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• pp.299-311
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• 2011

본 논문에서는 펄스 체이싱 스캔 방식을 이용한 바이스태틱 MTI 레이더 시스템에서 시스템 불안정 요인들을 식별하고 MTI 개선 성능에 미치는 영향에 대해 고찰하였다. 펄스 체이싱 스캔 방법은 송신 펄스 단위로 제한된 영역을 탐지하는 스캔 방법이며, MTI 필터는 작은 수의 펄스를 이용하여 클러터와 같은 간섭으로부터 표적을 분리할 수 있는 신호 처리 방법이다. 이상적인 MTI 신호 처리 과정은 클러터 자체의 특성에 의해서 클러터 감쇄 및 시스템 개선 성능이 제한되나, 제안된 바이스태틱 레이더 구조에서 MTI 성능은 펄스 체이싱 스캔 동안 수신빔 조향 오차에 의해 영향을 받을 수 있다. 또한, 바이스태틱 수신기에서 시간 동기 오차, COHO의 위상 오차 및 주파수/위상 동기 오차로부터 야기된 다른 시스템 불안정 요소들을 정의하고, 시스템 성능 개선에 미치는 영향들을 분석하였다.