• International Journal of Aeronautical and Space Sciences
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• 제9권1호
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• pp.147-161
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• 2008

In this paper, fine attitude estimation using low-cost sensors for attitude pointing missions of spacecraft is addressed. Attitude kinematics and gyro models including bias models are in general utilized to estimate spacecraft attitude and angular rate. However, a linearized model and a transition matrix are derived in this paper from nonlinear spacecraft dynamics with external disturbances. A Kalman filtering technique is applied and offers relatively high estimation accuracy under dynamic uncertainties. The proposed approach is demonstrated using numerical simulations.

• 제어로봇시스템학회논문지
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• 제8권2호
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• pp.167-177
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• 2002

In Strapdown Inertial Navigation System(SDINS), error models based on previously proposed conversion equations between the attitude errors, are only valid in case the attitude errors are small. The SDINS error models have been independently studied according to the definition of the reference frame and of the attitude error. The conversion equations between the attitude errors applicable to SDINS with large attitude errors are newly derived. Lyapunov transformation matrices are also derived from the obtained results. Furthermore the general method, which is independent of the attitude error and the reference frame to derive SDINS error model, is proposed using the Lyapunov transformation.

• International Journal of Internet, Broadcasting and Communication
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• 제13권4호
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• pp.169-175
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• 2021

The purpose of this study was to investigate the relationship between the formation of advertising attitudes and purchase intentions for users' products according to the difference in engagement of SNS sports advertisements and provide them with evidence to suggest directions for SNS sports advertising strategies. For this purpose, after establishing a hypothesis between engagement, advertising attitude, and purchase intention, a questionnaire was distributed to employees of sports administration organizations that have experienced or are using SNS and statistically processed using 460 copies of self-administeration. Through this process, we obtained the following results. First, it was found that engagement had a significant effect on advertising attitude. Second, it was found that engagement had a significant effect on purchase intention. Third, it was found that advertising attitude had a significant effect on purchase intention. From the results of this study, it can be seen that the SNS sports advertisement engagement has a positive effect on the attitude and purchase intention of advertisements conducted on SNS. In other words, it should be actively used to increase more efficient advertising attitudes and purchase intentions through this identified engagement.

• 로봇학회논문지
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• 제9권4호
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• pp.216-224
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• 2014

This paper compares methods for attitude estimation of a UUV(Unmanned Underwater Vehicle). Attitude estimation plays a key role in underwater navigation using DVL(Doppler Velocity Log). The paper proposes attitude estimation methods using EKF(Extended Kalman Filter), UKF(Unscented Kalman Filter), and CF(Complementary Filter). It derives methods using the measurements from MEMS-AHRS(Microelectromechanical Systems-Attitude Heading Reference System) and DVL. The methods are used for navigation in a test pool and their navigation performance is compared. The results suggest that even if there is no measurement relative to some absolute landmarks, DVL-only navigation can be useful for navigation in a limited time and range.

• 대한가정학회지
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• 제37권3호
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• pp.157-174
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• 1999

The purpose of this study is to investigate かe factors related to the environment-oriented consumer behavior, and to analyze the effects of environmental knowledge, perception of environmental problems, and environment-oriented attitude on the environment-oriented consumer behavior. The data used in this study were collected through questionnaires on 535 wives living in Cheju City. The data were analvzed by using SPSS WIN program. The summaries of this study are as follows. Using behaviors was influenced by age and family income, but buying and disposing behavior are not influenced by socio-economic variables of wives. Environmental knowledge only has effects on disposing behaviors, and environment-oriented attitude behavior has effects on buying, using, and disposing behavior. But the perception of environmental problems hasn't effects on them. Wives' environment-oriented behavior are more effected by environment-oriented attitude than perception of environmental problems. In buying behavior, environment-oriented attitude is the most influential factor, and the reference group is the second influential factor. But in disposing behavior, the reference group is the most influential factor, and environment-oriented attitude is かe second influential factor.

• International Journal of Aeronautical and Space Sciences
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• 제18권3호
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• pp.555-564
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• 2017

In this paper, a new technique for attitude and heading reference system (AHRS) using low-cost MEMS sensors of the gyroscope, accelerometer, and magnetometer is addressed particularly in vibration environments. The motion of MEMS sensors interact with the scale factor and cross-coupling errors to produce random errors by the harsh environment. A new adaptive attitude estimation algorithm based on the Kalman filter is developed to overcome these undesirable side effects by analyzing windowed measurement error covariance. The key idea is that performance degradation of accelerometers, for example, due to linear vibrations can be reduced by the proposed measurement error covariance analysis. The computed error covariance is utilized to the measurement covariance of Kalman filters adaptively. Finally, the proposed approach is verified by using numerical simulations and experiments in an acceleration phase and/or vibrating environments.

• 대한임베디드공학회논문지
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• 제7권2호
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• pp.61-70
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• 2012

This paper describes terrain-adaptive attitude controller for a hybrid mobile platform which operates in wheel & track mode. The wheel mode of the hybrid mobile platform allows quick driving performance in the flatland, while the track mode provides adaptive movement in the rough ground or stairway. The switching of the platform between two modes is automatically controlled by attitude controller algorithm. In addition, in the track mode, the platform automatically adjusts its attitude angle to overcome the obstacles in front. This paper demonstrates the attitude controller for the aforementioned wheel-track hybrid mobile platform in order to overcome terrain obstacles by using an adaptive method. The driving performance of the hybrid mobile platform has been tested and verified in various surrounding environments in both wheel and track mode. Further, this paper presents the experiments by using the track structure of mobile platform on forming adaptive attitude under various types of obstacles. The practicability and effectiveness of the proposed attitude controller of the platform has been demonstrated in urban building and a test-bed.

• 한국보건간호학회지
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• 제26권2호
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• pp.248-257
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• 2012

Purpose: The aim of this study is to examine the relationship between sexual consciousness and attitude among male university students. Methods: Data were collected using self-reported questionnaires from 235 male university students at two universities located in Busan. SPSS 12.0 using descriptive statistics, t-test, ANOVA, and correlation coefficient was used for data analysis. Results: In the area of sexual consciousness, sexual male chauvinism appeared to be strongest in the area of gender ($2.60{\pm}0.57$). In the area of sexual attitude, abortion appeared to be the most opened area ($2.36{\pm}0.54$) among all areas. Religion, pleasure attitude, premarital virginity, sex admissibility and homosexuality were found to be factors affecting overall sexual consciousness. On the other hand, religion, sexuality, and gender appeared to be the factors that affected overall sexual attitude. In addition, the result of this study demonstrated a positive correlation between sexual consciousness and attitude. Conclusion: Development of various sex education programs reflecting the liberal sexual attitudes of university students, and provision of opportunities for establishment of healthy sexual consciousness and sexual attitude among university students accordingly are needed.

• IEIE Transactions on Smart Processing and Computing
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• 제6권1호
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• pp.1-9
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• 2017

This paper proposes to improve the performance of a strap down inertial navigation system using a foot-mounted low-cost inertial measurement unit/magnetometer by configuring an attitude and heading reference system. To track position accurately and for attitude estimations, considering different dynamic constraints, magnetic measurement and a zero velocity update technique is used. A conventional strap down method based on integrating angular rate to determine attitude will inevitably induce long-term drift, while magnetometers are subject to short-term orientation errors. To eliminate this accumulative error, and thus, use the navigation system for a long-duration mission, a hybrid configuration by integrating a miniature micro electromechanical system (MEMS)-based attitude and heading detector with the conventional navigation system is proposed in this paper. The attitude and heading detector is composed of three-axis MEMS accelerometers and three-axis MEMS magnetometers. With an absolute algorithm based on gravity and Earth's magnetic field, rather than an integral algorithm, the attitude detector can obtain an absolute attitude and heading estimation without drift errors, so it can be used to adjust the attitude and orientation of the strap down system. Finally, we verify (by both formula analysis and from test results) that the accumulative errors are effectively eliminated via this hybrid scheme.

• 성인간호학회지
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• 제24권2호
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• pp.160-170
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• 2012

Purpose: The aim of this study was to assess knowledge, attitude, correct metered dose inhaler (MDI) use and compliance with self management among patients with chronic obstructive pulmonary disease (COPD). Methods: The participants of this study consisted of 109 COPD patients who were outpatients in C and K hospital located in G city from March 1 to September 30th, 2010. Data were measured using self-administered questionnaires and observational checklist. The data were analyzed using SPSS/WIN 18.0 program that included mean, standard deviation, ANOVA, Sheffe test, and Pearson's correlation. Results: There were significant relationships between knowledge and attitude (r=.33, $p$ <.001), between knowledge and correct MDI use (r=.37, $p$ <.001), and between knowledge and self-management compliance (r=.28, $p$=.003). There was significant relationship between attitude and self-management compliance (r=.33. $p$ <.001). In contrast, attitude was not significantly related to correct MDI use. Conclusion: The study showed that COPD knowledge and attitude of patients were related compliance in managing their disease. Therefore, strategies need to be utilized in education programs which would improve knowledge and subsequently improve attitude and compliance.