• KSII Transactions on Internet and Information Systems (TIIS)
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• v.2 no.1
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• pp.51-62
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• 2008

This paper proposes a second-order implicit constraint enforcement method which yields enhanced controllability compared to a first-order implicit constraints enforcement method. Although the proposed method requires solving a linear system twice, it yields superior accuracy from the constraints error perspective and guarantees the precise and natural movement of objects, in contrast to the first-order method. Thus, the proposed method is the most suitable for exact prediction simulations. This paper describes the numerical formulation of second-order implicit constraints enforcement. To prove its superiority, the proposed method is compared with the firstorder method using a simple two-link simulation. In this paper, there is a reasonable discussion about the comparison of constraints error and the analysis of dynamic behavior using kinetic energy and potential energy.

• PNF and Movement
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• v.8 no.1
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• pp.31-39
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• 2010

Purpose : The purpose of this study is to ascertain whether age, body mass index(BMI) and exercise frequency(EF) are correlated with knee joint position sense in healthy women. Methods : Healthy women of 150 who participated in this study were tested knee joint position sense; each reposition error was analyzed according to the age, BMI and EF. Reposition error was measured with a Myrin goniometer. Results : The age groups, BMI groups and EF groups demonstrated significant differences of the knee joint position sense. The older the healthy women are, the higher BMI is, and the lower EF is, the more decreased knee joint position sense has become. Conclusion : The older the women are, the higher BMI is, and the lower EF is, the more decreased the knee joint position sense in healthy women is. Therefore it needs to be considered to require management of obesity and regular exercise for prevention of knee injuries due to decreased joint position sense.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.435-439
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• 2002

In view of reliability assessment, the failure mode analysis by performance tests for machine tools is researched in this study. First, the error analysis with circular movement test data is studied. The various errors and their origins are analyzed by the error equations and then related parts and failure modes are investigated. Second, This paper deals with analysis of vibration testing for machine tools spindle. The various frequency components are classified by fourier transform and order analysis. The simple measuring devices and web-based analysis programs for each test are also developed.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.5
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• pp.94-102
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• 1998

In this paper, we proposed a dynamic selection scheme of advnaced prediction mode(DAPM), which reduces computational cost and improves coding efficiency. We can select the mode between default prediction mode (DPM) and advanced prediction mode (APM) according to motion componenets in a frame dynamically. For this purpose, we defined error distribution of motion estimation (EDME) as sum of absolute difference(SAD) for each searching points. This distribution region is divided to four subregions. We calculate minimum values in each subregions and then, we determine whether block motion estimation is performed or not depending on the results. As a result, we reduced computational complexity to 30% without degradation of image quality compared to fixed APM(FAPM) by selecting DPM for linear movement.

• Journal of information and communication convergence engineering
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• v.10 no.3
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• pp.269-275
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• 2012

In this paper, we proposed a novel location estimation algorithm based on the concept of space-time signature matching in a moving target environment. In contrast to previous fingerprint-based approaches that rely on received signal strength (RSS) information only, the proposed algorithm uses angle, delay, and RSS information from the received signal to form a signature, which in turn is utilized for location estimation. We evaluated the performance of the proposed algorithm in terms of the average probability of error and the average error distance as a function of target movement. Simulation results confirmed the effectiveness of the proposed algorithm for location estimation even in moving target environment.

• Journal of Sensor Science and Technology
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• v.13 no.1
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• pp.1-11
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• 2004

Due to various types of errors added to dynamic weight measurement data, proper methods to reduce measurement errors are required to produce reliable weights. To cope with parasitic types of errors in real systems, information provided by the various sensors is utilized and combined in such a way to reduce the measurement errors of load cells. In addition to four channels of load cells from a trailer, an accelerometer is used to obtain the information to compensate the error induced from vertical movement of the vehicle due to the variation of ground level. A model trailer system is run to verify the effectiveness of the proposed method to reduce noise of dynamic weight measurements. Experiments show that the processed error magnitudes of less than 20 g can be obtained for 10 Kg experimental loads.

• Proceedings of the KIEE Conference
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• 1995.07a
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• pp.291-293
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• 1995

LPM(Linear pulse motor) was developed as a prototype. In this paper, the design results of prototype and its dynamic characteristics are shown. The prototype was designed by using permeance analysis and the thrust value was also confirmed by comparing with the analysis results of the finite element method. To verify the performance of LPM. dynamic characteristics were measured. In slewing characteristic of the LPM, the thrust value of prototype LPM is higher than commercial level. A X-Y table was structured as a application of the prototype LPM. A controller and user's interface was also developed. By using this control system, the position error of X-Y table was checked. The repeat position error in linear movement was under than ${\pm}$ 100 micron.

• Journal of The Korean Association For Science Education
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• v.27 no.5
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• pp.404-411
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• 2007

The purpose of this study was to examine the types of explanation about different experimental data on students' preconceptions on physical experiment. 45 students were selected from P University by examining their pre-test. The subjects had a scientific conception about a simple pendulum's period of movement, and expected that there was no change in the movement even when the mass of water increased in the can. The students were presented data about pendulum movement inside a can. They recorded this in a blank table and drew a graph about the movement of the pendulum. The responses of students were tested by presenting written anomalous experimental data. Students' recognition, trust about the anomalous data, cognitive conflict, belief change about their preconceptions were examined with written tests also. To measure students' cognitive conflict levels, CCLT (Cognitive Conflict Levels Test) developed in a previous study was used. Some students responded based on preconceptions and regarded the data as manufactured data or experimental error. The students who recognized the anomaly in the situation showed higher cognitive conflict levels than those who didn't recognize the anomaly in the situation. The students who changed their beliefs about preconceptions recognized the data as anomalous situations and showed high cognitive conflict levels than those who didn't abandon their preconceptions. The students who have unchanged beliefs about their preconceptions regarded the data as experimental error.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.464-467
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• 1997

In this paper, a high precision track following control algorithm is proposed for micro electrostatic actuator considering of the application for hard disk drive. The micro electrostatic actuator proposed has nonlinear voltage-displacement characteristic in a working range of 0.8.mu.m and has uni-directional movement. Mid range reference and open-loop bias are proposed for the revision of negative position error, and inverse model for linearization.

• Proceedings of the KWS Conference
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• 1993.05a
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• pp.115-119
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• 1993

Many qualitive analyses of sampled process variables have been attempted to predict nugget size in resistance spot welding process. In this paper, dynamic resistance and electrode movement signal which is a good indicative of the nugget size was examined by introducing an artificial neural network estimator. An artificial neural feedforward network with back-propagation of error was applied for the estimation of the nugget size. To assess the advantage of this method. results have been compared with conventional regression method.