• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.4
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• pp.47-56
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• 2005

In GPS/INS/barometer navigation system for UAV, vertical channel damping loop was introduced to suppress divergence of the vertical axis error of INS, which could be reduced to the level of accuracy of pressure altitude measured by a pitot-static tube. Because static pressure measured by the pitot-static tube depends on the speed and attitude of the vehicle, static pressure error models, based on aerodynamic data from wind tunnel test, CFD analysis, and flight test, were applied to reduce the error of pressure altitude. Through flight tests and sensitivity analyses, the error model using the ratio of differential pressure and static pressure turned out to be superior to the model using only differential pressure, especially in case of high altitude flight. Both models were proposed to compensate the effect of vehicle speed change and used differential and static pressure which could be obtained directly from the output of pressure transducer.

• Journal of Aerospace System Engineering
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• v.12 no.2
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• pp.23-29
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• 2018

Contrail is type of clouds which are formed by a condensation of water vapour from the aircraft exhaust when the aircraft is flying the cold atmosphere. Since contrails have considerable effect on greenhouse-effect and military stealth efficiency, researches about contrail avoidance technology has been conducted for decades. However, none of the previous researches concerning contrail avoidance was carried out in Korea. Thus, review of the previous study regarding contrail reduction is absolutely needed. In this paper, researches conducted by several countries are categorically introduced, and practicabilities of their methods are analyzed. This paper also suggests some practical and systematized way to conduct future researches about contrail avoidance.

• Journal of the Korea Society of Computer and Information
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• v.20 no.1
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• pp.247-254
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• 2015

This study is to explore the effects of adolescent's stress on juvenile delinquents and the moderating effects of communication between adolescent and the parents. For this study, we sampled and surveyed middle school students. The analytical results are the followings. Juvenile's stress has a significant effects on juvenile's delinquents and the level of communication between juveniles and the parents is an important factor concerned with juvenile's delinquents. This study suggested some policy implications based on this results.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3D
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• pp.511-517
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• 2006

In this paper, we studied the techniques to analyze the flying safety area focused on the air base rules for military that has been the criteria of the altitude restrictions around the airfield for both civilian and military purposes in Korea. We wanted to present the effective method to analyze the restricted area and to help solving problems that could result recently from the altitude restrictions around the airfield at the beginning of the development projects. To do this we proposed the methods to effectively generate the model of the flying safety area in accordance with the air base rules using 3D GIS techniques and to automatically identify the obstructions caused by the natural and man-made features in those areas. To apply the proposed methods actually to the airfield chosen for the study area, we presented the approaches to generate geospatial informations based on the commercial digital maps and satellite imagery and by generating the flying safety area model, identifying the obstructions, and visualizing the integrated model for the flying safety area analysis we showed the practical usability of the proposed techniques.

• Korean Journal of Social Welfare Studies
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• v.43 no.1
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• pp.5-29
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• 2012

The present study was to explore what makes adolescents think of themselves as troublemakers even without conduct problems. It was expected that the failure to attain socio-developmental milestones(e.g., healthy relationships with others, academic achievement) would lead to form trait aspect of deviant self-concept. A latent state-trait autoregressive modeling was used to analyze five annual waves of data from 3,449 adolescents taken from the Korean Youth Panel Study. We decomposed trait and state aspect of deviant self-concept and identified significant predictors of trait-like deviant self-concept, while additionally testing for gender differences. Our results showed that conduct problems had greater effect on deviant self-concept among girls compared with boys. Conduct problem was most predictive of deviant self-concept, and yet both poor peer-relations and school failures predisposed adolescents to have deviant self-concept. Low academic achievement conferred risk for trait aspects of deviant self-concept with no gender difference, whereas poor peer relation was more predictive among girls. It highlights the cultural value system underlying self-concept and how and why adolescents think of themselves as troublemakers.

• 대한공업교육학회지
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• v.37 no.1
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• pp.21-41
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• 2012

The objective of this study was to examine the relation between delinquency and career maturity in school adolescents and to determine whether activities for enhancing career maturity can have protective effects against juvenile delinquencies. Research questions for this study are: first, how serious school adolescents' delinquencies are; and second, what relation there is between delinquency and career maturity in school adolescents. Third, how different is school adolescents' career maturity according to their experience in delinquencies? The results of this study were as follows. First, 55.8% of the school adolescents committed one or more of the 14 types of delinquent acts included in the delinquency inventory during the last one year, and the percentage was higher among male students than among female ones. Second, no correlation was observed between the school adolescents' overall delinquency level and overall career maturity. According to the sub-factors of career maturity, however, the overall delinquency level was in a negative correlation with objectiveness and a positive correlation with independence/decisiveness. That is, objectiveness was higher in the group without experiences in delinquencies than in the group with such experiences. and Type II status offenses (truancy, runaway) was in a negative correlation with overall career maturity, and in a negative correlation with objectiveness and confidence. Third, no significant difference was observed in career maturity between those with experience in delinquencies and those without. Among the sub-factors of career maturity, however, objectiveness was higher in those without experience in delinquencies than in those with. and Overall career maturity, and objectiveness and confidence among the sub-factors of career maturity were significantly higher in those without experience in Type II (truancy, runaway) status offenses than those with. The results of this study suggest that the objectiveness of career maturity can be a protective factor against juvenile delinquency. Furthermore, they suggest that activities for enhancing career maturity may protect adolescents from Type II status offenses. These results may provide basic materials necessary to develop career counseling approaches and interventions strategies for preventing school adolescents' delinquencies.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1993.04a
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• pp.35-39
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• 1993

항공기의 플러터 현상을 예방키 위한 개발시의 주요 공학적 임무로는 플러 터 해석, 풍동 플러터 시험, 실기체에 대한 지상진동시험 및 비행 플러터 시 험이 있다. 이들 업무는 군용 항공기의 경우에는 군사 규격서, 민간 항공기 의 경우는 FAR 규정 등에 항공기 개발 및 개조시에는 필히 수행토록 명시 되어 있으며, 특히 개발항공기의 인증을 받기 위해서는 초도 비행전까지 필 수적으로 완료되어야 하는 업무이다. 이중 항공기 지상진동시험은 개발항공 기의 초도 비행전에 실기체를 대상으로 하는 구조 동특성 규명시험으로써 플러터 해석 모델의 정확도를 입증하고 그 해석모델을 수정하거나 개선시키 는데 필요한 구조의 동특성 변수들을 실험적으로 규명하는 시험이다. 이 시 험은 개발된 항공기의 초도비행허가를 획득하고 비행속도제한을 설정키 위 해서 초도비행 직전에 초도 개발 비행기를 대상으로 필수적으로 수행되어야 하는 필수적 시험이다. 이에 따라 개발된 항공기의 전기체 지상진동시험을 수행하였고, 시험데이터의 모달해석을 하였다. 이 시험을 수행하기 위해 3개 의 가진기를 사용하였고, 모두 159개의 지점에서 주파수응답 함수를 얻었다. 최대 48 채널의 데이터 획득시스템을 사용하였으므로, 네번에 걸쳐 측정위치 를 옮겨 전체데이타를 획득하였다. 지상진동 시험의 최종해석 결과는 유한요 소 모델의 유효성을 검토하는데 사용되었고, 시험 데이타를 이용한 가진응답 해석(Forced Response Analysis)을 통하여 비행플러터 시험시에 사용되는 플러터 가진기의 위치선정 및 가진력의 크기를 결정하는데 이용하였다.ncy)가 저주 파수대로 천이(Lower Shift)하는 현상이 나타났으며, 일정한 작업량이라도 작업중량을 줄이고 작업 빈도를 높여서 작업할 경우에 이러한 현상이 더욱 두드러졌다. 작업시간의 경과에 따른 MVIS의 감소 현상은 작업빈도가 높고 비대칭형 작업일 때 가장 크게 나타났다. 총손실을 줄이고, 상대적 비용절감효과를 갖게할 수 있다고 하였다. 따라서 본 연구에서는 성인 여성기성복의 치수적합성을 높이기위하여 출산 후 중년에 접어 들면서 체형이 변화되는 것을 고려하여 연령을 분류하고(18세-34세, 30세-51세), 각 연령 집단에 따른 체형을 각각 3가지로 분류하였다. 이에 따라 의복 생산시의 총손실을 줄이기위한 상의, 하의생산시 필요한 부위별 최적규격치 간격을 제시하였다.적인 기능으로 보여지는 것에 좁혀서 작업능력의 연령증가 변화에 대하여다원적 평가를 하는 것이 실제적이라고 할 수 있다. 따라서 본 연구에서는 인간이 가지고 있는 다수의 기능중에서 수지교 치성과 연령증가와의 관계를 조사한다. 만약 연령증가 만으로 수지교치성을 평가 할 수 없는 경우에는 어떠한 요인이 수지기민성의 변화에 영향을 미치는가를 검토한다.t list)에서 자동적으로 사건들의 순서가 결정되도록 확장하였으며, 설비 제어방식에 있어서도 FIFO, LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.16-29
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• 2016

The total area of paddy field was estimated to be 55 % of the cultivated lands in South Korea, which is approximately 1 million hectares. Organisms inhabiting paddy fields if they are sensitive to environmental changes can be environmental indicator of paddy fields. Biological indicators such as phenology and distributional range are evaluated as intuitive and quantitative method to analyze the impact of climate change. This study aims to estimate flight time change of Hydrophilidae species' based on the RCP 8.5 climate change scenario. Unmanned monitoring systems were installed in Haenam, Buan, Dangjin and Cheorwon relative to the latitudinal gradient. In the three regions excepting Cheorwon, it was able to measure the abundance of flying Hydrochara affinis and Sternolophus rufipes. Degree-day for the flight time was determined based either on field measurement values and estimates of 2020s, 2050s and 2080s from KMA climate change scenario data. As a result, it is found that date of both species of initial flight becomes 15 days earlier, that of peak flight becomes 22 days earlier and that of final flight does 27 days earlier in 2080s compared to 2020s. The climate change impact on flight time is greater in coastal area, rural area and valley than inland area, urban area and plan. H. affinis and S. rufipes can be used as climate change indicator species.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.13 no.1
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• pp.1-8
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• 2005

The purpose of the study is to show the need for the development of standard materials which can be used for flight training and pilot practical tests in the future. In this paper the flight training and evaluation references of flight training institutes certified by the Ministry of Construction and Transportation(MOCT) are compared with references of the international organization such as ICAO and FAA. As a result it is found that the flight schools certified by the MOCT have used different references for flight training and evaluation. Therefore, this study suggests creation and operation of an expert advisory group to develop new standards for flight training and evaluation, so called " Flight Training Manual", in Korea.

• Proceedings of the Korea Contents Association Conference
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• 2003.11a
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• pp.395-401
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• 2003

다목적 대형 댐의 건설로 수몰된 과거의 삶의 공간을 20년이 지나서 다시 복원한다는 것은 그곳에 살던 실향민 등에게는 참으로 반가운 소식이다. 본 연구에서는 1980년대 초에 완공된 충주댐으로 인하여 물 속에 잠긴 청풍지구를 수몰이전의 입체 지형 공간적으로 원형복원하기 위한 원격탐사 기법을 적용한 것이다. 비교적 해상도가 좋은 인공위성 사진자료와 댐 수몰이전의 디지털 위성영상 데이터를 수집하고, 수몰직전에 제작된 지형도를 이용하여 위성영상자료의 통합 적용하여 수몰직전의 지형공간정보를 현재시간으로 영상 복원하기 위하여 원격탐사 기법을 적용한 것이다 이를 위하여 지형도에서 추출한 등고선과 현재의 등고선과의 접목을 통하여 청풍 주변지역을 중심으로 당시의 수치표고모형을 생성하였다. 또한 이를 입체적으로 보여주기 위한 투시조감도를 각 방향에서 생성함으로서 수몰이전의 아름다운 모습을 3차원적으로 영상복원 하였다. 또한 좀더 가까이서 수몰마을을 보기 위한 근접비행시뮬레이션 동영상을 제작하여 과거 기억 속의 고향을 영상에서 찾아볼 수 있도록 한 것이다.