• Journal of the Korean Data and Information Science Society
• /
• 제20권3호
• /
• pp.563-575
• /
• 2009

본 연구는 Priester 등 (2004)에 의해서 제시된 기억기반 선택상황에서 태도-의사결정 통합모형인 '고려상표군과 선택에 대한 태도 및 태도강도의 영향모형'을 자극기반 선택상황으로 확장하였다. 즉 태도 및 태도강도가 고려상표군과 선택변수에 대한 역할 (모형 타당성측면)과 외부자극 요소인 제품 디스플레이 위치에 따른 물리적 현저성 강도의 역할 (모형 일반화측면)을 통해 모형의 확장가능성을 검토하였다. 본 연구는 기존 연구와 같이 태도 그 자체를 측정하여 행동이나 행동의도를 파악하는 대신에 '행동에 대한 태도'를 직접 측정할 수 있는 실험조사 방법을 토대로 로지스틱 회귀분석을 통해 실증적으로 분석하였다. 본 연구 결과는 기억기반에서 태도-의사결정간의 관련성에 대한 통합모형으로 제시된 모형의 특성들을 자극기반 상황에서 이론적 배경과 실증분석을 통해 모형타당성을 확인하여 모형의 일반화 가능성을 보여주었다.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2008년 영문 학술대회
• /
• pp.561-565
• /
• 2008

Generally, reaction wheels or thrusters are used for attitude control of a satellite. There is a potential method for the attitude control utilizing the plasma flow on the Low Earth Orbit. In the present study, experiments which simulate attitude control of a Low Earth Orbit Satellite using the ionosphere were conducted. In this experiment, a plasma flow was generated by a steady-state Hall type accelerator. However it is known that the Hall type accelerator, which is used as plasma source, produces a torque around its axis called "swirl torque". This torque would affect the attitude control in the above-mentioned experiments. First of all, we conducted the measurement of the swirl torque. Secondly, experiments using a satellite model with negative electrodes were conducted. The negative electrodes generated torque around the axis, and controlled the attitude of the satellite model by changing the applied voltage.

• Journal of Astronomy and Space Sciences
• /
• 제13권2호
• /
• pp.67-81
• /
• 1996

The attitude dynamics of KITSAT-1 are modeled including the gravity gradient stabilization method. We define the operation scenario during the initial attitude stabilization period by means of a magnetorquering control algorithm. The required constraints for the gravity gradient boom deployment are also examined. Attitude dynamics model and control laws are verified by analyzing in-orbit attitude sensor telemetry data.

• International Journal of Aeronautical and Space Sciences
• /
• 제14권1호
• /
• pp.58-66
• /
• 2013

This paper addresses the performance of three different types of attitude control systems for the Quad-rotor UAV to perform the flip maneuver. For this purpose, Quad-rotor UAV's 6-DOF dynamic model is derived, and it was used for designing an attitude controller of the Quad-rotor UAV. Attitude controllers are designed by three different methods. One is the open-loop control system design, another is the PD control system design, and the last method is the sliding mode control system design. Performances of all controllers are tested by 6-DOF simulation. In case of the open-loop control system, control inputs are calculated by the quad-rotor dynamic model and thrust system model that are identified by the thrust test. The 6-DOF realtime simulation environment was constructed in order to verify the performances of attitude controllers.

• Journal of Astronomy and Space Sciences
• /
• 제9권2호
• /
• pp.203-212
• /
• 1992

인공위성의 자세결정을 위해 3축 magnetometer에 의해 측정된 지구 자기장의 자료와 IGRF 모델(tilted-eccentric dipole 모델)을 사용하였다. 지구자기장 모델으 값들을 계산하여 magnetometer 측정자료들과 비교해 보았고 이것으로부터 두 자세각 $\alpha$ 각과 $\beta$들을 구하였다. 이 두 각들을 이용하여 자세결정에 사용되는 Z 축과 자기장의 수직성분 사이의 실 자세각 $\gamma$ 에 대한 bound $\gamma1$과 $\gamma2$를 계산하여 UoSAT-11, 14, 22의 자세 상태를 알아보았다.

• 한국생활과학회지
• /
• 제16권5호
• /
• pp.1031-1040
• /
• 2007

The purpose of this study was to assess the causal relationships of attitude toward fish eating, health involvement, convenience, fish consumption and age. A total of 235 questionnaires were completed. Structural equation model was used to assess the causal relationships among constructs. Results of the study demonstrated that the structural equation analysis result for the data also indicated excellent model fit. The influences of age on health involvement and convenience were statistically significant. The influences of health involvement on attitude toward fish eating and fish consumption behavior were statistically significant. The influence of convenience on fish consumption behavior were statistically significant. Moreover, the age had a significant indirect effect on attitude toward fish eating through health involvement. The age also had a significant indirect effect on fish consumption behavior through convenience.

• Advances in aircraft and spacecraft science
• /
• 제4권3호
• /
• pp.335-351
• /
• 2017

Kalman filter based spacecraft attitude estimation has been used in many space missions and has been widely discussed in literature. While some models in spacecraft attitude estimation include spacecraft dynamics, most do not. To our best knowledge, there is no comparison on which model is a better choice. In this paper, we discuss the reasons why spacecraft dynamics should be considered in the Kalman filter based spacecraft attitude estimation problem. We also propose a reduced quaternion spacecraft dynamics model which admits additive noise. Geometry of the reduced quaternion model and the additive noise are discussed. This treatment is easier in computation than the one with full quaternion. Simulations are conducted to verify our claims.

• 한국생활과학회지
• /
• 제17권1호
• /
• pp.141-150
• /
• 2008

The purpose of this study was to assess the causal relationships among hedonic belief, ambivalence, subjective norm, attitude and meat consumption behavior. A total of 318 questionnaires were completed. Structural equation model was used to measure the causal effects of constructs. Results of the study demonstrated that fit of the restricted baseline model is significantly worse than that of the unrestricted proposed model, in which more parameters are estimated. The effects of hedonic belief, ambivalence and subjective norm on attitude were statistically significant. The effects of hedonic belief, subjective norm and attitude on meat consumption were statistically significant. The effect of attitude on intention was statistically significant. Moreover, attitude played a mediating role in the relationships between hedonic belief and meat consumption, between ambivalence and meat consumption, and between subjective norm and intention. This study suggested that the consumer decision-making process for eating meat products is best modeled as a complex system that incorporates both direct and indirect effects on meat consumption. This study believed the evidence presented supports this position. Moreover, this study appeared to be a worthy area of pursuit.

• 한국식생활문화학회지
• /
• 제23권3호
• /
• pp.328-335
• /
• 2008

The objective of this study was to evaluate the causal relationships among environmental belief, ambivalence, subjective norm, attitude and meat consumption behavior. A total of 318 questionnaires were completed. A structural equation model was employed to assess the causal effects of constructs. The results of the study demonstrated that the structural analysis results for the data also indicated excellent model fit. The effects of environmental belief, ambivalence, and subjective norm on attitude were statistically significant. The effects of environmental belief, subjective norm and attitude on meat consumption were statistically significant. The effects of attitude on intention were statistically significant. As had been expected, intention exerted a significant effect on meat consumption. Moreover, environmental belief and ambivalence exerted significant indirect effects on meat consumption through attitude. Subjective norm exerted a significant indirect effect on meat consumption through attitude and intention. Subjective norm also exerted a significant indirect effect on intention through attitude. In developing and testing conceptual models which integrate the relationship among behavioral belief, attitude variable, behavioral intention and meat consumption, this study may approach a deeper understanding of the complex relationship among meat consumption behavior-related variables. Greater understanding of the complex relationship among meat consumption behavior-related variables can improve the practical or managerial diagnosis of the problem and opportunities for different marketing strategies including meat production and meat product development and marketing communication.

• 한국콘텐츠학회논문지
• /
• 제9권10호
• /
• pp.492-499
• /
• 2009

본 연구는 학습자의 효과적 학습을 위해 온라인 상 콘텐츠 품질을 구성하는 요소와 오프라인 강의가 콘텐츠 품질을 인식하는데 얼마나 영향을 주는가를 알아보기 위한 연구이다. 다속성 태도모델(multiattribute attitude model)의 속성만족도-중요도 모델(attribute satisfaction-importance model)을 중심으로 온라인 학습에 있어 콘텐츠 품질이 학습태도에 미치는 영향과 오프라인 강의를 병행했을 때의 학습태도(learning attitude) 형성의 변화에 대한 관계를 살펴보고자 한다. 콘텐츠 만족도에 대한 신념(belief)은 콘텐츠 품질을 구성하는 요소로 음성강의, 동영상강의, WBI방식 강의로 나누어 평가한다. 여기에 웹상의 강의와 오프라인 강의를 병행했을 때 형성되는 학습태도의 변화에 대해 연구한다.