• Journal of Institute of Control, Robotics and Systems
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• v.15 no.9
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• pp.909-915
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• 2009

This work is to develop a vision system for high precision alignment between upper and lower plates required at the imprinting process of the large LCD flat panel. We compose a gantry-stage that has highly repeated accuracy for high precision alignment and achieves analysis about thermal transformations of stage itself. Position error in the stage is corrected by feedback control from the analysis. This system can confirm alignment mark of upper and lower plates by using two cameras at a time for the alignment of two plates. Pattern matching that uses geometric feature is proposed to consider the recognition problem for alignment mark of two plates. It is algorithm to correct central point and angle for the alignment from the recognized mark of upper and lower plates based on the special characteristics. At the alignment process, revision for error position is performed through Look and Move techniques.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.6
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• pp.463-472
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• 2017

Inertial Navigation System Alignment is the process to determine direction cosine matrix which is the transformation matrix between the INS body frame and navigation frame. INS initial position value is necessary to INS attitude calculation, so that user should wait until he get such value to start the INS alignment. To remove the waiting time, we propose an alignment algorithm that immediately starts after the INS power on by using pseudo initial position input and then is completed with attitude error compensation by entering true position later. We analyse effect of INS sensor error on attitude in process of time and verify the performance and usefulness of the close-loop alignment algorithm which corrects attitude error from the change of initial position.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3703-3716
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• 2022

Target alignment technology is one of the most critical technologies in laser fusion experiments and is an important technology related to the success of laser fusion experiments. In this study, by combining the open-loop and closed-loop errors of the target alignment, the Kalman state observer is used to estimate the position of the target, which improves the observation precision of the target alignment. Then the optimized result is used to guide the alignment of the target. This method can greatly optimize the target alignment error and reduce uncertainty. With the improvement of the target alignment precision, it will greatly improve the reliability and repeatability of the experiments' results, thereby improving the success rate of the experiments.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.3
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• pp.1-6
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• 2009

This paper presents a geometrical error compensation of tool alignment for sharp edge bite on B axis controlled machine. In precision micro patterning, bite alignment is crucial parameter for machined surface. To decrease bite alignment error, plus tilted bite from B axis center is touched to reference work piece(pin gauge) and checked the deviation from original position. Same process is repeated for maximum touch deviation value. From this touched position value, wheel alignment error in X axis and Z axis can be calculated on B axis center. Experimental results show that this compensation method is efficient to correct sharp edge bite alignment.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.708-715
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• 2010

In Strapdown Inertial Navigation System, alignment accuracy is the most important factor to determine the performance of navigation. However by an existing self-alignment method, it takes a long time to acquire the alignment accuracy that we want. So, to attain the desired alignment accuracy in as little as $\bigcirc$ minutes, we have developed the precise multi-position alignment method. In this paper, it is proposed a inertial measurement matching transfer alignment method among alignment methods to minimize the alignment error in a short time. It is based on a mixed velocity-DCM matching method be suitable to the operating environment of vertical launching system. The compensation methods to reduce misalign error, especially azimuth angle error incurred by measurement time-delay error and body flexure error are analyzed and evaluated with simulation. This simulation results are finally confirmed by experimentations using FMS(Flight Motion Simulator) in Lab and the integration test to follow the fire control mission.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.54 no.1
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• pp.26-32
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• 2005

Rotor position information is essential in the operation of the switched reluctance motor(SRM) drive for generation the phase current switching signals. When an incremental encoder is used as a rotor position sensor, the initial rotor position can not be detected. Some sensorless rotor position estimation methods also have the same problem. In these systems, to initially align the rotor, the forced alignment method has a delay and reverse rotation before the motor can start. Therefore it can not be acceptable for unidirectional drive systems. So the forced alignment method is not desirable in all drive systems and the research on the SRM drives should be directed to a system without rotor alignment. In this paper, a new detection method of initial rotor position using the rate of change of current is suggested. Firstly, di/dt versus θ/sub R/ reference table, which is the relation between the rate of change of current and rotor position, is generated and then the squared Euclidean distance method is used to estimate the rotor position based on the table. The simulated and experimental results are presented demonstrating the feasibility and accuracy of this method.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.28 no.1
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• pp.39-51
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• 2022

Background: The purpose of this study is to investigate the effect of neck and shoulder self-stretching exercise using audiovisual media on neck pain, postural alignment, and joint position error in women with chronic neck pain. Methods: The subjects included 20 women that gave consent to participate in the study voluntarily. They performed the self-stretching exercises using audiovisual media was carried out 20 minutes 5 times a week during 3 weeks. Neck disability index (NDI) and visual analogue scale (VAS) were used to measure the functional disability and pain, A pressure pain threshold was measured using an algometer, and a cervical range of motion (CROM) measurement tool was used to measure the range of motion and error of proprioceptive position sense of the cervical spine. To assess posture alignment, forward head angle (FHA), forward shoulder angle (FSA) were measured using image J software. Results: The neck pain intensity was statistically significantly within group (p<.05). Neck and shoulder functional disability were a statistically significant difference within group (p<.05). Splenius capitis and upper trapezius pressure pain threshold were statistically significant difference in within group (p<.05). The postural alignment was statistically significantly within group (p<.05). The cervical range of motion in neck extension, right and left lateral flexion were statistically significantly within group (p<.05). The joint position error in neck flexion, extension, right and left lateral flexion decreased statistically significantly within group (p<.05). Conclusion: Self-stretching exercise using audiovisual media increased the mobility of the neck, decreased neck pain and joint position error, and improved posture alignment. As a result, there was a positive effect by applying the self-stretching exercise using audiovisual media to people with neck pain. Based on this, it is thought that it can be used as the basis for research related to home training programs for healthy self-management.

• The Journal of Korean Physical Therapy
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• v.28 no.1
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• pp.33-38
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• 2016

Purpose: The aim of this study was to determine the effectiveness of pelvic tilt training using an inclinometer on joint position sense and postural alignment in individuals with stroke. Methods: Thirty-one subjects with chronic stroke were divided into two groups: the experimental group (16 subjects) and the control group (15 subjects). Subjects in both groups received neuro-developmental therapy five times per week. In addition, the patients in the experimental group also received pelvic tilt training using an inclinometer for 30 minutes, 3 times a week for 4 weeks. Maximal range of anterior, posterior pelvic tilt and joint position sense were used to evaluate pelvic tilt motion. Image analysis was performed for evaluation of postural alignment on in standing position. Results: Significant difference in Iimprovement of pre- and post-intervention of joint position sense was observed showed significant difference (p<0.05) in all groups. Experimental groups showed sSignificant differences in maximal range of posterior pelvic tilt in on the paretic side were observed in the experimental groups compared to with the control group (p<0.05). Conclusion: These findings suggest that pelvic tilt training using an inclinometer may help to improve range of pelvic tilt and joint position sense of stroke patients.

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.23-29
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• 2009

Purpose: This study examined the effects of the symmetrical scapular alignment on the weight bearing of hemiplegic patients in the standing position. Methods: PALM (PALpation Meter) test and Gaitview AFA-50 were used to measure the skeletal alignment of the scapula and the weight bearing loaded on the affected and unaffected sides before and after training. The data was analyzed using a paired t-test on the SPSS 12.0 program for descriptive statistics. A p value <0.05 was considered significant. Results: The mean difference in the scapular alignments on sup. & mid. & inf. area in the hemiplegic side before and after training was $0.93\pm0.50cm$ and $0.58\pm0.43cm$, respectively. There was a significant decrease after training rather than that before (p<0.05). The mean weight bearing on the foot area in the hemiplegic patients before and after training was $9.12\pm5.51N/cm^2$ and $4.36\pm4.11N/cm^2$, respectively,. There was a significant decrease after training rather than that before (p<0.05). The scapuar alignments and weight bearing data on the standing position were grouped around the average (to central point) in the distribution graph. Conclusion: These findings suggest that the symmetrical scapular alignment can serve as an effective means of improving the weight bearing ability of hemiplegic patients.

• Journal of Korean Medicine Rehabilitation
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• v.18 no.4
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• pp.161-169
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• 2008

Objectives : This study was carried out to investigate the relationship of pelvic alignment between AP view of the pelvis in standing and supine position. Methods : Sixteen healthy peoples who get $51.59{\pm}4.14$ as average in SF-36 were evaluated by X-ray findings. After measuring innomiate measurement, off centering measurement, sacral ala measurement, illium shadow measurement, the area of obturator foramen, those were analyzed statistically. Results : It was not all to be corresponded to distort pelvic alignment of AP view of the pelvis in standing and in supine. Sometimes it was the opposite result. Conclusions : These results suggest that the diagnosis of pelvic alignment to go through on each position is brought about disagreement with each other.