• 한국군사과학기술학회지
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• 제23권6호
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• pp.565-573
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• 2020

Unlike fin-stabilized projectiles, there has been some difficulty measuring the attitudes of spin-stabilized projectiles during the long-range flight due to their high spin rates. In this work, solar and geomagnetic sensors were used to measure the attitude of a spin-stabilized projectile. A method to calculate the attitude of the projectile from the signals of the sensors was introduced as well as the methods to process the signals of the sensors. To validate the methods, the attitude of a projectile was calculated with the sensor signals from the actual flight data.

• International Journal of Aeronautical and Space Sciences
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• 제3권2호
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• pp.1-12
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• 2002

This paper considers the robust and optimal three-axis attitude stabilization of rigid spacecraft with inertia uncertainties. The attitude motion of rigid spacecraft described in terms of either the Cayley-Rodrigues parameters or the Modified Rodrigues parameters is considered. A class of robust nonlinear control laws with relaxed feedback gain structures is proposed for attitude stabilization of rigid spacecraft with inertia uncertainties. Global asymptotic stability of the proposed control laws is shown by using the LaSalle Invariance Principle. The optimality properties of the proposed control laws are also investigated by using the Hamilton-Jacobi theory. A numerical example is given to illustrate the theoretical results presented in this paper.

• 경영과학
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• 제29권1호
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• pp.115-129
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• 2012

Service Encounter employees play a crucial role in service delivery and building relationships with customers and their attitudes and behaviors towards customers determine customers' perceived service quality and satisfaction. Past research indicates that TQM managerial practices are a critical determinant of employee's attitude and performance in the workplace. Therefore, this study investigates a model examining the relationship among TQM, employees' attitude and service performance in a hospital. Our measurement results were acceptable in terms of reliability and validity. The statistical testing shows significance on the positive relationship in the sequential order of TQM, employee's attitude and service performance. In conclusion, the theoretical and practical implications of this study were discussed, along with its limitations.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2007년도 한국우주과학회보 제16권2호
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• pp.135-138
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• 2007

The present work is to estimate the stability region of the State-Dependent Riccati Equation (SDRE) controlled system, which is used for a decentralized coordinated attitude control in satellite formation flying. In this research, currently emerging methods which estimate region of attraction for the SDRE controllers are introduced and the methods are applied to attitude control systems. The results guarantee the stability of the given decentralized coordinated attitude control system in satellite formation flying.

• 한국군사과학기술학회지
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• 제3권2호
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• pp.131-139
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• 2000

A design of CPS attitude determination system is described in this paper. The designed system is a low cost high precision 24 channel single frequency GPS(Global Positioning System) receiver which provides a precise absolute heading and pitch (or roll) as well as a position. It uses commercial chip-set and consists of two RF parts, two signal-tracking parts, a processor, memory parts and I/Os. In order to determine precise attitude, accurate carrier phase measurements and an efficient integer ambiguity resolution method are required. To meet these requirements, a PLL (Phase Locked Loops) is designed, and an algorithm called ARCE (Ambiguity Resolution with Constraint Equation) is adopted. The hardware and software structure of the system will be described, and the performance evaluated under various conditions will be presented. The test results will promise that more reliable navigation system be possible because the system provides all navigational information such as position, velocity, time and attitude.

• 한국군사과학기술학회지
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• 제12권1호
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• pp.44-50
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• 2009

In this study, the relationship between military pilot's spatial ability and unusual attitude recovery was investigate. MRT(Mental Rotation Test) was measured with spatial ability whereas recovery time and error rates were mearsured with respect to 11 unusual attitudes. Eight fighter pilots and eight rear cockpit pilots of F-4E participated in this study. The results showed that MRT response time was significantly correlated with unusual attitude recovery time. The regression equation showed that unusual attitude recovery time was linearly related to MRT response time and could be explained by MRT response time more than 66%. In conclusion, it is recommended that a training is needed to improve the mental rotation ability in a visually restricted environments during maneuvering.

• 항공우주기술
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• 제1권1호
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• pp.65-71
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• 2002

다목적 실용위성의 자세제어계 mode는 크게 Sun, Maneuver, Science Mode로 나누어진다. 이중 Manuever Mode는 다시 Attitude Hold submode 와 Δ-V Burn submode로 나누어진다. 본 논문은 지상으로 송신된 playback 데이터를 이용하여 자세제어계 Maneuver Mode의 동작상태를 주로 분석하였다. Maneuver Mode중 attitude hold submode에서의 nadir pointing performance, 그리고 Δ-V Burn submode에서의 pitch/ roll 90도 maneuver 후 추력기 점화 과정에 대한 성능 분석을 수행하였으며 자세제어계 서브시스템 설계 규격을 만족함을 검증하였다.

• 대한지구과학교육학회지
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• 제16권3호
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• pp.351-362
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• 2023

이 연구는 중학생의 자기조절학습 전략과 같은 인지적 요인과 과학에 대한 태도, 과학적 자기효능감과 같은 정의적 요인의 과학 핵심역량에 대한 직·간접 효과를 검증하여 변인 간의 구조적 관계를 규명하고자 하였다. 이를 위해 광역시 소재 S 중학교의 전학년 학생 438명의 자료를 사용하여 변인 간의 인과 관계를 살펴보았다. 중학생의 자기조절학습 전략, 과학에 대한 태도, 과학적 자기효능감은 과학 핵심역량에 직접적인 영향을 미쳤으며, 자기조절학습 전략은 과학에 대한 태도, 과학적 자기효능감에 직접적인 영향을 미치는 것으로 나타났다. 또한 중학생의 자기조절학습 전략은 과학에 대한 태도와 과학적 자기효능감을 매개로 과학 핵심역량에 간접적인 영향을 미쳤다. 그러므로 중학생의 과학 핵심역량 함양을 위해서는 인지적 요인인 자기조절학습 전략과 정의적 요인인 과학에 대한 태도와 과학적 자기효능감을 고려한 종합적 관점에서 학생들을 교육할 필요가 있다.

• 한국임상보건과학회지
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• 제3권2호
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• pp.361-371
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• 2015

Purpose. The purposed of this study was done to DNR attitude and terminal care performance among hospital nurses. Methods. The participants were 207 nurses working in hospital nurses in D and G cities. Data on DNR attitude and terminal care performance were collected via questionnaire between April 2015 and July 2015. Data analysis was done with SPSS 12.0 program and included one-way ANOVA, independent t-test, and Pearson correlation. Result. DNR attitude of participants in this study were shown to have high levels (DNR attitude: M=32.64/60, SD=6.14). Terminal care performance of participants in this study were shown to have poor levels (physical M=20.72/32, SD=3.77, psychological M=20.26/32, SD=3.85, spiritual M=9.62/24, SD=3.65). The attitude of the hospital nurse was significantly different according to the marital status. The terminal care performance was significantly different according to experience of terminal care. The DNR attitude by nurses was positively correlation to physioloical terminal care performance(r=.137, p<.049) but the relationship between the psychological terminal care performance( r=.016, p=.815) and spiritual terminal care performance showed no correlation(r=-.099, p=.157). Conclusion. The results of this study indicate that it is necessary to increase DNR attitude and to encourage terminal care performance among hospital nurses.

• 한국산학기술학회논문지
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• 제19권7호
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• pp.125-132
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• 2018

본 연구의 목적은 어린이집 유아교사들의 과학교수효능감과 유아의 과학적 태도가 어떤 관계를 보이는지 살펴 본 후, 교사-영유아와의 상호작용의 질을 높일 수 있는 매개변인으로 교수창의성을 투입하여 교사 영유아와의 관계가 어떻게 변화되는지를 알아보는 것이다. 본 연구는 2018년 경기 수원지역의 어린이집 유아교사 303명을 대상으로 설문조사를 실시하였고, 자료 분석을 위해 SPSS 23.0과 AMOS 23.0을 이용하여 구조방정식 모형과 Sobel-test를 실시하였다. 분석결과, 유아교사의 과학교수효능감은 유아교사의 창의성과 유아의 과학적 태도에 긍정적인 영향을 미치는 것으로 나타났다. 또한 유아교사의 창의성은 유아의 과학적 태도에 긍정적인 영향을 미치는 것으로 나타났다. Sobel-test 결과, 유아교사의 과학교수효능감과 유아의 과학적 태도 간의 관계에서 유아교사의 창의성은 매개역할을 하여 유아의 과학적 태도를 증진시키는 데에 중요한 변수로 작용하였다. 결론적으로 유아교사의 교수 창의성은 유아의 과학적 태도 향상을 위해 긍정적인 영향을 미치는 중요한 변인임을 확인하였다. 따라서 유아교사가 과학교수활동을 할 때 교수 창의성을 높일 수 있는 교육이 동시에 제공된다면 유아의 과학적 태도의 질을 높이는데 기여할 수 있을 것이다.