• International Journal of Control, Automation, and Systems
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• v.2 no.3
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• pp.289-297
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• 2004

This paper deals with the design and control of passive multiple trailer systems for practical applications. Due to the cost and complexity of the trailer mechanism, passive systems are preferred to active systems in this research. The design and control objective is to minimize the trajectory tracking errors occurring in passive multiple trailers. Three sorts of passive trailer systems, off-hooked, direct-hooked, and three-point, are discussed in this paper. Trajectory tracking performance and stability issues under constant curvature reference trajectories are investigated for these three types. As well, various simulations and experiments have been performed for each type. It is shown that the proposed off-hooked trailer system produces a tracking performance that is superior to the others.

• Korean Journal of Applied Biomechanics
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• v.13 no.3
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• pp.1-14
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• 2003

This study was conducted to investigate the principles and motions for increasing the jumping height of Fosbury Flop. The subjects were three male jumpers who were former Korean national team players. Their jumping motions were analyzed using the DLT method of three-dimensional cinematography. The conclusions were as follows. 1. The horizontal velocity of approach run and decreasing of this velocity during the take off phase were increased as the jumping height was increased. Therefore, in order to increase the jumping height, the horizontal velocity of approachrun should be increased and decreased properly during the take-off phase. The average height of the analyzed Dials was 2.15m. The average horizontal velocity of approachrun was 7.49m/s and decreased to 4.16m/s at the instance of take-off. 2. The vertical velocity of the center of gravity was increased as the ascending height of the center of gravity during the take-off phase was increased. Therefore, the center of gravity at the instant of touch down should be lowered. This could be possible by increasing the length of the last stride and the backward lean angle of the body. The average length of the last stride was 111.1% of the standing height, the average height of the center of gravity was 46.6% of the standing height and the average backward lean angle of the body was 40.3 degrees.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.06a
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• pp.236-242
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• 2001

In this paper the effect of bump compliance, load, and the number of pad on the lift-off speed is studied. When the load is greater and bump compliance lower, the shaft is lifted off at higher rotating speed. And when the load is applied near the center of pad, lift-off speed is lower. When the number of pad increases, the lift-off speed is higher. The lift-off characteristics can be used to lengthen the life time of the coating and design the rotating machinery supported by bump bearings.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.948-951
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• 2005

New technology that reduces photolithography process steps from 4 to 3 in fabrication of TFT LCD is introduced. The core technology for 3mask-TFTs is the lift-off process [1], by which the PAS and PXL layer are formed simultaneously. To evaluate the stability of this lift-off process, outgases from photo resist on a substrate during ITO deposition and the quality of ITO film were analyzed and the conventional photo resist stripper machine which operates lift-off process was examined to see its ability to reduce particle problems of the machine. Through the development of total process and design for TFTs using this 3mask technology, panels in TN and IPS modes which exhibit same performances of a display using a conventional process were achieved. In addition, this process was already verified in the mass production line and now some products are being produced by the 3mask technology.

• International journal of advanced smart convergence
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• v.9 no.2
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• pp.38-48
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• 2020

The shaking-off the dust from balustrade of higher stories may cause the higher risk of falling accident rate. Main purpose of this study was to quantify an effect of balustrade heights and blanket types on possibility of falling accident relative to one's motor controllability during shaking-off the dust of the blanket from balcony. Female participants, who consisted of total 10 under condition of balustrade height of 3 kinds (90 cm, 110 cm, 130 cm) and blanket types (0.4 kg, 1.6 kg, 3 kg, 200^⁎230 cm), performed repetitively the task of shaking-off the dust of the blanket. Vertical position and velocity of center of mass due to increase of blanket weigh in case of balustrade height of 90 cm was increased, but vertical ground reaction force was decreased swiftly. That is, the higher balustrade height was, the less distance difference between center of mass and center of pressure was.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.10
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• pp.1141-1145
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• 2011

Recently, there are many issues about R2R printing technique for mass production of electronic devices. Among the various Roll-to-roll based printing techniques such as gravure, off-set, flexo and so on, "Gravure off-set printing technique" has an advantage of higher printing resolution. The printing unit of gravure off-set printing technique usually consists of plate roll, blanket roll and impressure roll whose. Linear velocities should be synchronized each other for fine pattern printing. However, roller's manufacturing error and printing variations such as pringting pressure, printing speed, roll stroke and so on actually affected their synchronization anf thus the quality of fine fattern. In this paper, we analyzed the effective of synchronization error on printing quality. Also, this paper reviews the relative motion with each roll. And, this paper studys the synchronization error about its generation problem.

• International Journal of Advanced Culture Technology
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• v.3 no.2
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• pp.34-41
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• 2015

Bonding strength of a thermal sprayed coating is difficult to measure using a conventional pull-off test method. Scratch test is a potential alternative testing method. An adhesive and a cohesive bond strength of the coating can be measured by the pull-off test while the scratch test performed on the cross-section of the thermal sprayed coating can only demonstrate the cohesive bond strength of the coating. Nevertheless, it is still beneficial to perform the scratch testing on the cross-section of the coating for the sake of comparison thus providing an alternative to the pull-off test. The scratch test method can reduce testing time and cost in the long run due to a significant cost reduction in consumables and energy and time saving from the curing step of the glue used in the pull-off test. This research investigates the possibility of using the scratch test to measure the cohesive bond strength of Mo/NiCrBSi composite coating. The results from the pull-off test and the scratch test indicate that the cohesive bond strengths of the Mo composite coating show similar trend and that the cohesive bond strength are increased when increasing NiCrBSi content.

• International Journal of Contents
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• v.2 no.3
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• pp.22-26
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• 2006

In this paper we introduce a new circle detection algorithm for occluded on/off pupil and iris boundary extraction. The proposed algorithm employs 7-step processing to detect a center and radius of occluded on/off eye images using the property of the chords. The algorithm deals with two types of occluded pupil and iris boundary information; one is composed of circle-shaped, incomplete objects, which is called occluded on iris images and the other type consists of arc objects in which circular information has partially disappeared, called occluded off iris images. This method shows that the center and radius of iris boundary can be detected from as little as one-third of the occluded on/off iris information image. It is also shown that the proposed algorithm computed the center and radius of the incomplete iris boundary information which has partially occluded and disappeared. Experimental results on RGB images and IR images show that the proposed method has encouraging performance of boundary detection for pupil and iris segmentation. The experimental results show satisfactorily the detection of circle from incomplete circle shape information which is occluded as well as the detection of pupil/iris boundary circle of the occluded on/off image.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.17-18
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• 2002

Last year, a three-year research program was started in order to establish an external audit system to radiotherapy QA in Japan. It consists of questionnaire surveys, mailed (off-site) dosimetry and visited (on-site) dosimetry at radiotherapy facilities in Japan. The first questionnaire was sent to all Japanese radiotherapy facilities in October 2001, surveying basic QA procedures at each facility. 628 answers were returned with the return rate of 87%. In February 2002, the second questionnaire was sent. Off-site and on-site dosimetry have been tested in several facilities, and will be started soon. We anticipates that this program will gradually grow to a radiotherapy quality control center similar to Radiological Physics Center at MD Anderson Hospital.

• Journal of TMJ Balancing Medicine
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• v.13 no.sup
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• pp.1-8
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• 2023

Objectives: Parkinson's disease (PD) is currently the most rapidly increasing degenerative brain disease due to population aging and westernization of lifestyle. Levodopa is the most commonly used drug to manage PD symptoms. However, levodopa has a problem in that the wearing-off phenomenon occurs as the duration and dose of administration increase. In order to investigate the wearing-off phenomenon in PD patients and devise countermeasures, we conducted a questionnaire survey in Korea. Methods: For the study, a questionnaire with a total of seven items was prepared. Part IV of the MDS-UPDRS (Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale) and the WOQ-9 (9-symptom Wearing-off Questionnaire) were used as references. Results: Of the 48 patients who completed the questionnaire, all 47 patients who completed the questionnaire experienced the wearing-off phenomenon. Only one of the patients diagnosed with PD a year ago did not experience the wearing-off phenomenon. Patients frequently mentioned a lack of sleep and stress as aggravating factors for wearing-off. They also stated that in order to resolve the off-state, they walked, massaged, warmed up the body, stretched and exercised. Conclusions: Because wearing-off is such a common occurrence, it is thought necessary to develop wearing-off prevention and resolution measures that PD patients can use in their daily lives.