• Journal of the Korean Society for Aviation and Aeronautics
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• v.30 no.4
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• pp.191-198
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• 2022

Stress refers to various body reactions that occur when humans are stimulated by environmental conditions. The quality of education and flight skills can suffer if flight trainees are constantly subjected to high stress, even in the case of flight trainees, and as a result, it can harm becoming a pilot. It is therefore the aim of this study to identify stress factors (flight training, career, financial support, relationships with family and teachers) that student pilots face, to determine how these factors affect flight and academic immersion and abandonment, and to improve the quality of flight education.

• Defense and Technology
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• no.10 s.176
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• pp.8-9
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• 1993

록히드사가 제작한 마하 3의 첩보 비행기 SR-71 Blackbird가 1990년에 첩보 비행 임무를 종료하게 되었을 때, 많은 항공 전문가들은 미 공군이 무언가를 숨기고 있다고 생각하였다 지금까지 나타난 여러가지 징후들을 종합해 보면 SR-71의 후속비행기로서 마하 6의 속도를 가진 첩보 비행기가 존재한다는 심증이 굳어지고 있다 다른 첩보 비행기를 운용할 계획도 없이 SR-71만 운용 중지키로 하고 더 이상 이 문제에 대한 언급이 없는데 대해, 대부분의 군사 전문가들은 미 공군이 세계에서 가장 빠르고 고공으로 비행하는 비행기를 운용 중지하면서 그 후속 대안없이 손을 뗀다는 것과, 그럴 경우 정보수집임무의 많은 것을 포기해야한다는 점에 강한 의문을 소개한다 미 정부 관리들은 이런 종류의 비행기를 보유하고 있지 않다고 부인하면서 위성을 이용해 첩보 비행기가 수행하던 임무를 충분히 수행할 수 있다고 말하며, 또한 록히드사에서도 SR-71 후속 첩보기를 개발하는데 참여한 바 없다고 부인하고 있으나, 그동안 수집된 자료를 종합해보면 미 정부가 이 비밀 첩보기의 존재를 자의로 밝히던지 또는 타의에 의해 밝혀지던지 곧 노출될 것으로 보인다

• Journal of Astronomy and Space Sciences
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• v.22 no.1
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• pp.21-34
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• 2005

The initial conditions that generate bounded motion in eccentric reference orbit are determined for satellite formation flying. Because Hill's equations cannot describe the relative motion between two satellites in eccentric orbit, a new relative dynamics utilizing the nonlinearity and eccentricity correction for Hill's initial conditions is implemented. The constraint that matches angular rates of chief and deputy satellites is used to obtain the bounded motion between them. The constraint can be applied to satellite formation motions in eccentric orbit, since it implicates J2 perturbation due to the central body's aspherical gravitational forces. The periodic bounded motions are analyzed for the orbit with the eccentricity of less than 0.05 and about 0.5 km relative distance between chief and deputy satellites. It is mainly illustrated that the satellite formations in small eccentric orbits can have hounded motions; consequently, the formation can be kept by matching angular rates of the satellites. These results demonstrate an useful method that reduces the cost for operating satellites by providing effective initial conditions for satellite formation flying in eccentric orbit.

• The Korean Journal of Air & Space Law and Policy
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• v.22 no.1
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• pp.105-123
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• 2007

The launching of the Taepo-dong 1 on 31 August 1998 by the North Korea was the first case where the diplomatic protests was made against the flight, the purpose of which, the launching State claimed, consisted in space exploration and use. It is the principle regarding the freedom of space exploration and use, as included in the international treaty, that is relevant in applying the various rules and in defining the legal status of the flight. Its legal status, however, was not actually taken into account, as political negotiations leading to the test moratorium has been successful until present day in freezing the political crisis. This implies that the rules of the law lack the validity and logic sufficient in dictating the conduct of the States. This case shows that, in effect, it is not the rule but the politics that is to govern the status of the flight.

• The Korean Journal of Air & Space Law and Policy
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• no.spc
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• pp.87-104
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• 2007

The launching of the Taepo-dong 1 on 31 August 1998 by the North Korea was the first case where the diplomatic protests was made against the flight, the purpose of which, the launching State claimed, consisted in space exploration and use. It is the principle regarding the freedom of space exploration and use, as included in the international treaty, that is relevant in applying the various rules and in defining the legal status of the flight. Its legal status, however, was not actually taken into account, as political negotiations leading to the test moratorium has been successful until present day in freezing the political crisis. This implies that the rules of the law lack the validity and logic sufficient in dictating the conduct of the States. This case shows that, in effect, it is not the rule but the politics that is to govern the status of the flight.

• Korean Journal of Social Welfare
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• v.53
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• pp.75-104
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• 2003

This study was performed to analyze the process and develop the pattern of school dropout in the context of the Korean educational systems. Participants were 30 adolescents experiencing dropout one more times and their age ranged from 16 to 23. A major category derived and analysed from a grounded theory method of Strauss and Corbin(1990). The qualitative analysis indicated that dropout is contradictory experiences in Korea. Because it is emancipation from various distress of school systems as well as loss of various benefit as students, Main causes of dropout were identity problems, school frustrations(failure in school achievements), environmental disadvantaged and delinquencies. Sometimes these various causes are emerged at the same time. Most important condition of context which was decided was whether dropout was voluntary and considered. After dropout from school, it was important if there were resources such as emotional and informative supports. Especially informative support was critical to adjust after dropout. Dropout experience was divided largely into 4 patterns such as type of 'searching the identity', 'being disorganized', 'escaping' and 'frustration'. In chronological analysis resulted in 4 stages including 'stage I. loss of motivation', 'stage II. escaping from school', 'stage III. trial and error', 'stage IV changing the meaning of dropout in the life.

• Journal of Advanced Navigation Technology
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• v.20 no.3
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• pp.252-257
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• 2016

In this paper a novel access scheme for uplink multiuser transmission based on IEEE 802.11ax random access in in-aircraft wireless sensor networks is proposed. The proposed scheme provides an efficient access control mechanism with three divisions of OFDMA backoff counter (OBO): access, deferring, dropping, which controls the number of potential uplink transmission stations. The proposed scheme can be used efficiently in in-aircraft wireless sensor network where a large number of sensors need to be supported. By using the proposed scheme, since in-aircraft sensors attempt channel access using the proposed differentiated OBO parameters, the number of stations exceeds the access capacity can be efficiently controlled. This paper also provides the mathematical analysis of the proposed scheme, regarding the optimal parameters. According to the performance analysis, the proposed scheme is able to efficiently control the access behavior of wireless sensors in the network.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.2 no.1
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• pp.43-48
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• 1991

The College entrance examination stress syndrome is a kind of anxiety disorder. The underlying cause of this disorder is not a test anxiety itself. One's hidden inner and familial conflicts are more likely attributed to this disorder. Patient's the most common complaints are various psychosomatic symptoms but in severe cases underlying psychopathology may be activated and progress to major psychosis. In a broad sense adolescent's delinguent behavior, drug abuse, school drop-out and sucide are closely related to this syndrome. In clinical management of these patients, considering the special situation of impending examination, the therapist must access to central conflict theme in a short time without severe resistance. The authors classified this syndrome into 5 clinical subtypes ; 'the anxious group', 'the exhaustion group', 'the despair group', 'the emptyness group' and 'the boredome group'. Typical case of each subtype and it's management methods were presented briefly.