• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.271-275
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• 2006

This paper describes the design and realization of full attitude system based on MEMS IMU and GPS carrier phase. The work can be divided into two parts: First, initial heading is determined by using two GPS receivers. And this paper discusses the usage of space geometry conditions to reduce the range of ambiguity search. The method presented in this paper was tested on the static. On the static condition, an accuracy better than 0.06 degrees for heading for 3.48m long baseline has been achieved. Integration of GPS and low cost MEMS IMU are used to realize the real-time heading attitude system. Second, level attitude (pitch and roll) is determined using the method of frequency-velocity for the feedback control. At the same time, the method using the attitude based on MEMS IMU to help determination of the range of ambiguity search is proposed. The results done on the sea show that an alternative means to provide real-time, cost-effective, accurate and reliable attitude information for attitude surveys. Though motivated by a big ships application, the design can be applied to other vehicles.

• 간호행정학회지
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• 제1권2호
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• pp.325-337
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• 1995

This study attempted to increase quality of nursing care by assessing the nurses' attitudes for computerization in nursing practice and ensuring right recognition and attitude for computerized system. Study subjects are 311 nurses who are working at 4 general hospitals. Those hospitals are selected according to the degree of computerized in Kyoung In Province. Study instrument consists of 20 items and 12 general questionnaire which was developed by Brodt and Stronge(1985) and modified by Lee(1991). Data collection was done from april 19th in 1995 to april 29th. Data gathered were analized number, t-test, ANOVA by using SPSS. The study results are as follows : 1. Study subject's attitude for computer application showed positive response as mean score of 3.44 especially nurses who had experience using computer showed 100% pro-response. 2. Study subject's attitude by age was significant statistically(F=3.9589, p=.0038), among them age 25-30 revealed the highest positive scores, and age 40 showed the lowest positive scores. 3. Study subject's attitude by education level showed no significant difference(F=1.4182, 2437), and those who are more educated showed more positive response. 4. Study subject's attitude by duty years showed no significant difference(F=2.2648, p=.0622), and those who had 7- 9 duty years had the highest positive attitude however those who have 10 duty years showed lowest positive attitude. 5. Study subject's attitude by position revealed no significant difference(F=2.0017, p=.1369), and the charge nurse groups who were using computer showed the highest scores. 6. Study subject's attitude by computerized type showed significant difference(F=23.9665, p=.0000), and G hospital which had computer system in nursing area obtained the highest positive scores. 7. study subject's attitude by presence of computer education showed no significant differenec(F=.9002, P=.3435), and non computer educated groups showed the highest positive response. 8. Study subject's attitude by computer education place revealed no significant difference(F=4.3723, p=.0020). and the groups who were taught individually or in the institution obtained the highest positive scores. 9. Study subject's attitude by duty year computer use showed no significant response(F=.9591, P=.3282), and groups of computer use showed the high degree of positive response. 10. Study subject's attitude by duty year using computer showed significant difference(F=5.9174, p=.0009),and the groups using computer for 6 years or group of 4-6 years showed the highest degree of positive response and the groups using computer for 1 year showed the lowest degree of positive response.

• Journal of Positioning, Navigation, and Timing
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• 제13권3호
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• pp.237-244
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• 2024

An Attitude and Heading Reference System (AHRS) provides the attitude of a vehicle with a constant velocity using an Inertial Measurement Unit (IMU) and a magnetometer. In this case, in order to avoid the disadvantage of a gyroscope, an AHRS using a Gyro-Free IMU (GF-IMU) that is composed of only accelerometers may be considered instead of the gyroscopes. In this paper, a design method of an AHRS using a GF-IMU is proposed. The proposed AHRS consists of roll and pitch calculation, yaw calculation, angular acceleration and angular velocity calculation, attitude calculation, and a Kalman filter. In particular, since the angular velocity cannot be measured from a gyroscope, the angular acceleration is obtained from the accelerometer output, and the angular velocity is calculated by integrating it. In order to show the usefulness of the proposed method, a performance evaluation was carried out. The performance evaluation results show that the attitude estimation performance of the proposed AHRS is similar to that of the conventional AHRS.

• 보건교육건강증진학회지
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• 제21권3호
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• pp.87-100
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• 2004

Objective: This research has been conducted in order to conduct sex education using information and communication technologies (ICT) which is currently taught to elementary school students, understand how this method of education affects the knowledge of and attitude towards sexual health in them, so that it could be actually applied in classrooms. Subject: 115 students were divided into three different groups: a comparison group of 38 students (who were given no sex education at all), control 2 group of 39 students (who were given sex education via video programmes), and control 1 group of 38 students (who were given sex education using ICT). Research Tool: A questionnaire used by the literature studies. After verifying content validity, it was modified and supplemented in this way: sex knowledge was reduced to 26, and sex attitude was also reduced to 11. The reliability of the research tool was Cronbach's a=0.86 for sex knowledge tool, and Cronbach's a=0.81 for sex attitude tool. The collected data have been analysed using SPSS 11.0 program. The content validity was analysed by factor analysis and multiple regression analysis, and hypothesis verification was analysed using repeated measure ANOVA test. Result: 1) In sex knowledge marks, there was a significant difference according to the group (p=.009) and point of time (p=.000), and there was a significant interaction between the groups and point of time(P=.000). As a result, it turned out that both video programmes and ICT were significantly effective in improve the knowledge. 2) In sex attitude marks, there were no significant differences according to the group (p=.213), but there was a significant difference according to point of time (p=.002), and there was a significant interaction between the groups and point of time(P=.018). As a result, it turned out that only the education method using ICT was effective in improving the attitude. Conclusion: From the results of this research, it can be said that the sex education using ICT was the most effective method in improving the sex knowledge and attitude of students at elementary school. Therefore, it is advisable that the sex education methods using ICT should be developed and applied continuously.

• 제어로봇시스템학회논문지
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• 제14권9호
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• pp.881-885
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• 2008

To calculate the attitude in ARS(Attitude Reference System) using 3 gyros and 3 accelerometers, gyro drift must be compensated with accelerometer to avoid divergence of attitude error. Kalman filter is most popular method to integrate those two sensor outputs. In this paper, new Kalman filtering method is proposed for roll and pitch attitude estimation. New states are defined to make linear equation and algorithm for changing Kalman filter parameters is proposed to ignore disturbances of acceleration. This algorithm can be easily applied to low cost ARS.

• International Journal of Aeronautical and Space Sciences
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• 제6권2호
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• pp.17-22
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• 2005

As one of validation tool for attitude determination system, we have used various constraints using priori information which is known through base vector set up. However these conventional constraints cannot guarantee validity in terms of final solutions such as Euler angle. So we suggest attitude boundary concept to verify the final attitude solution on the flying airplane, it is based on the combination of velocity based attitude estimation technique and ambiguity resolution. we can say it can check invalid solution effectively at just one epoch without repeatability test of resolved cycle ambiguity. In this paper we show that the suggested constraint can effectively reject incorrectly resolved cycle ambiguity the conventional constraints have missed.

• 대한전기학회논문지
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• 제45권2호
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• pp.265-272
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• 1996

In this paper, attitude computation algorithm for a strap down ARS(Attitude Reference System)of an underwater vehicle has been studied. Attitude errors o the ARS using low-level gyroscopes tend to increase with time due to gyroscope errors. To cope with this problem, a mixing algorithm of accelerometer aided attitude computation has been developed. The algorithm can successfully bound the error increase for cruising motion, but it gives instantaneously large errors when a vehicle maneuvers. To improve the performance in case of vehicle's maneuver, a new attitude computation mixing algorithm complying state of vehicle and to manage the adjustment of the gains which are invariant in the existing algorithm. In addition, a gain scheduling method is applied to fuzzy inference composition process for real-time computation. Monte Carlo simulation results show that the proposed algorithm provides better performance than the existing algorithm.

• 반도체디스플레이기술학회지
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• 제9권2호
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• pp.41-47
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• 2010

In this paper we suggest an improvement upon the previous method of estimating a body's attitude. This paper presents a method that overcomes the shortcomings of previous studies. Applying the method of separating the acceleration of gravity component from the accelerometer's output improves the performance of the attitude estimation and extends the scope. In order to apply the method of the attitude estimation in an actively moving body, a new acceleration value containing the acceleration of gravity is calculated. This paper also proposes the method which minimizes the estimation error in estimating the moving body's attitude which is changing rapidly. Finally, this paper suggests a method that detects the gyroscope's drift and compensates for this drift using accelerometer. Applying the method improves the performance of the attitude estimation.

• 제어로봇시스템학회논문지
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• 제12권3호
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• pp.300-306
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• 2006

In this paper an error analysis of 3-dimensional GNSS attitude determination system is given. The attitude error covariance matrix is derived and analyzed. It implies that attitude errors are affected by the baseline length and configuration, the satellites numbers and geometry, receiver measurement noises and the nominal attitude of the vehicle. By defining Euler Angle Dilution Of Precision (EADOP) which is analogous to GDOP, roll, pitch and yaw errors can be efficiently analyzed. However the expression of the attitude error is too complex to get some intuitions. Therefore with a commonly adopted assumption, new expressions for attitude error are derived. The formulas are easy to compute and represent the attitude error as a function of the nominal attitude of a vehicle, the baseline configuration and the receiver noise. Using the formula, the accuracy of the attitude can be analytically predicted without the computer simulations. Applications to some widely used configurations reveal the effectiveness of the proposed method.

• 한국의류산업학회지
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• 제10권4호
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• pp.506-514
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• 2008

The purpose of this study was to investigate the effect of attitude towards parent brand on extended fashion products in case of fashion brand extension. The subjects of this study were 386 college students and data were collected using survey questionnaire. For data analysis, factor analysis and path analysis were applied. The results showed that there were four factors (e.g., familiarity attitude, emotional attitude, value-expressive attitude, utility information attitude) in attitude towards parent brand and six factors (e.g., economical risk, utilitarian risk, social risk, psychological risk, time/advantage loss risk, risk for losing opportunity) under perceived risk in extended product. The results showed that attitude towards parent brand had a negative effect on perceived risk in extended products and had a positive effect on attitude towards extended products. Perceived risk in extended products then had a negative effect on purchase intention of extended products whereas attitude towards extended products had a positive effect on purchase intention of extended products.