• Transactions of Materials Processing
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• v.18 no.2
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• pp.172-176
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• 2009

In this paper, new aspherical surface polishing mechanism is suggested to polish aspherical glass lens mold by both airbag polishing tool and reverse-rotational eccentric motion. Up to now, conventional aspherical lens polishing method by the small tool polishing uses the aspherical surface profile and the trajectory of the polishing tool is also controlled. However, full contact concept by airbag polishing tool and no position control make the easy polishing setup and does not need aspherical design profile. An aspherical lens polishing machine was made for this study and a tool mark removal experiment fur the fine-grounded lens mold was successfully performed.

• Journal of Korean Society of Steel Construction
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• v.11 no.1 s.38
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• pp.89-98
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• 1999

The objective of this paper is to investigate the structural behavior of concrete filled steel tubular columns subjected to eccentric load. With experiment and analytical study, the buckling behavior of columns is investigated and compared with each other to the view of main parameters. Appling foreign standards in the experimental results, we suggested new strength formula of concrete-filled steel tubular columns. The parameters are slenderness, eccentric ratio, and concrete filled or not. The experiment are carried out by simple loading.

• Structural Engineering and Mechanics
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• v.73 no.1
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• pp.83-95
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• 2020

In this work, a mathematical model of beam-column system carrying a double eccentric end mass system is investigated, and solved analytically based on the exact solution analysis. The model considers the case in which the double eccentric end mass is a rigid storage tank containing fluid. Both Timoshenko and Bernoulli-Euler beam bending theories are considered. Equation of motion, general solution and boundary conditions for the present system model are developed and presented in dimensional and non-dimensional format. Several important non-dimensional design parameters are introduced. Symbolic and/or explicit formulae of the frequency and mode shape equations are formulated. To the authors knowledge, the present reduced closed form symbolic and explicit frequency equations have not appeared in literature. For different applications, the results are validated using commercial finite element package, namely ANSYS. The beam-column system investigated in this paper is significant for many engineering applications, especially, in mechanical and structural systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5789-5796
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• 2011

This study examined the effect of VT(Vibration Training) on the symptoms of DOMS (Delayed-Onset Muscle Soreness) before induced by eccentric exercise of the left leg triceps surae. Twenty one healthy adult men and women who had not participated in a regular exercise program for the lower extremities were assigned to one of two experimental groups: vibration training group, Control group. We measured the VAS(Visual Analogue Scale), ankle plantar flexor strength, triceps surae circumference, CK(Creatine Kinase) before and after exercise and 24, 48 and 72 hours after eccentric exercise. After inducing DOMS, VAS showed significant differences between groups at a point of time 48 hours, and showed significant differences within groups in accordance with the time of measurement(p<.05). Plantar flexor strength of groups with VT did not show significant difference between groups but, showed significant differences within groups in accordance with the time of measurement(p<.05). Triceps surae circumference of groups with VT did not show significant difference between groups but, showed significant differences within groups in accordance with the time of measurement(p<.05). CK of groups with VT did not show significant difference between groups but, showed significant differences within groups in accordance with the time of measurement(p<.05). As a result of the study, VT prior to eccentric exercise is effective to inhibit pain. So, this method can be suggested to prevent DOMS in doing an unfamiliar activites.

• The Journal of Korean Physical Therapy
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• v.13 no.1
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• pp.19-31
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• 2001

The twenty one individuals with total knee replacement who were admitted to Kang-Dong Hospital for comprehensive physical therapy were studied in order to demonstrate the effectiveness of an isokinetic test program using the Cybex 6000 machine. The subjects were divided into three groups with the isometric exercise group receiving isometric exercise. the isokinetic eccentric exercise group, and isokinetic eccentric exorcise group receiving isokinetic exercise(eccentric. concentric) to knee flexors and extensors muscles for a six weeks period using the Cybex 6000. The results were follow :1 . The peak torque was increased significantly in the flexors and extensors of the isokinetic conccentric exorcise among three groups(p<.05). 2. The progress of peak torque was increased significantly in the flexors and extensors of the isokinetic conccentric exercise among three groups(p<.05). 3. The total work was more increased significantly in the flexors and extensors of the isokinetic conccentric exercise among three groups(p<.05). 4. The progress of total work was more increased significantly in the flexors and extensors of the isokinetic conccentric exercise among three groups(p<;.05). 5. The ratio of endurance was not increased significantly in all three groups. 6. The extensors in the peak torque was likely to recover rapidly than the flexors. 7.The average R.O.M in the pre-exercise and post-exercise was not different significantly in all three groups. According to the above results, In the muscle strength recovery for total knee replacement patients, isokinetic concentric exercise group was significantly greater than the isokinetic eccentric and isometric exercise groups after a six weeks training.

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.295-307
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• 1997

This study was performed to investigate the reproductibility of eccentric mandibular movements according to preferred chewing side, range of mouth opening, type of lateral guidance and involvement of temporomandibular disorders. 50 patients with temporomandibular disorders and 65 dental students without any signs and symptoms were randomly selected for this study as the patients group and the control group, respectively. For recording and observation of eccentric mandibular movement trajectory, BioEGN$^\textregistered$ of Biopak$^\textregistered$ system (Bioresearch Inc., USA) was used. Each eccentric movement to anterior, right and left side was performed three times similar to the movement pattern for Pantronic Reproducibility Index. mandibular path was analyzed by three dimensional positional change and the three paths from one direction were compared with one another. From this, reproducibility index of one-directional lateral movement could be calculated, and total reproducibility index, named BioEGN reproducibility index(BERI), was also computed from three-directional eccentric movement likewise. BioEGN reproducibility Index could have four value of score by small or large scale, and by outgoing or incoming movement. The data were analyzed by SAS/stat program and the results obtained were as follows: 1. Right side chewing subjects showed more consistent pattern In reproducibility index in comparison between patients group and control group than left chewing subjects have done, and reproducibility was low in patients group. However, there was no difference between the two stoups in bilateral chewing subjects. 2. There were no difference in reproducibility index between preferred chewing side and contralateral side in unilateral chewing subjects whereas reproducibility index in left side on outgoing movement were higher than in right side in bilateral chewing subjects. 3. Difference in total reproducibility index(BERI) between canine guidance group and non-canine guidance group were not observed though difference in reproducibility index on lateral movement were observed in part. 4. There were no difference in reproducibility index between affected side and contralateral side in unilaterally affected patients, and between unilaterally affected patients and bilaterally affected patients in patients group. 5. Highly significant positive correlationship were shown among the four 쇼pes of total reproducibility index(BERI) in total subjects, and range of clinical mouth opening was negatively correlated with BEBI on outgoing movements and with index on outgoing movement to preferred side.

• Korean Journal of Oriental Medicine
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• v.13 no.3
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• pp.29-37
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• 2007

Narratives are the old stories handed down for a long time, which are not personal creations but common ones for ages. They were formed from the public consciousness, passed orally and recorded in letters. There have been lots of studies on narratives about characters, whereas there have been poor in the studies on the great doctors. The author examined the narratives about great doctors in literature for successive generations, and made researches on world view and consciousness of reality reflected on the age directly or indirectly. The author inquired into the descriptions and constructions of the narratives separately, and classified the great doctors in literature into the miraculous doctors, eccentric doctors and righteous doctors. Therefore truly great doctor is the one who treats not only personal diseases but also social problems, and who tries to harmonize with human beings and nature.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1609-1613
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• 2003

This research focused on the development of automatically exclusive production equipment of corrupad as changing manual system into automatic system to increase the output. Therefore the minimization of the problem of the rewinding mechanism with eccentric cantilever structure is key to the achievement of the high performance for automation production. Proto-type corrupad rewinding machine is manufactured after considering the effect of the rotational vibration and natural frequency of the structure of machine by using 3D design packages such as ADAMS and I-deas. For evaluating the performance of the proto-type machine, simulations of dynamic and static characteristics using 3D design packages, a series of modal tests by accelerometer and measurements of dynamic behavior by high-speed camera for rewinding part, were carried out. As a result, the proto-type machine was not affected with the rotational vibration. Whirling error of eccentric cantilever structure in driving is small. Therefore the machine developed is most suitable to produce corrupad automatically. However reinforcement of the structure in axial direction is required due to so vibration in that direction.

• Physical Therapy Rehabilitation Science
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• v.5 no.1
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• pp.40-46
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• 2016

Objective: The purpose of this study was to examine the effect on multifidus and external oblique abdominis muscle activation during hip contraction of three types (concentric, isometric, eccentric) in standing position. Design: Cross-sectional study. Methods: Twenty healthy adult men volunteered to participate in this study. Muscle activation was recorded from gluteus maximus, both multifidus, and both external oblique abdominis by surface electromyography (EMG) while holding position in the type of gluteus maximus contraction. EMG values were normalized by maximum muscle contractions (% maximum voluntary isometric contraction). All subjects performed hip extension with three contraction methods. The type of gluteus maximus contraction using Thera-band was composed of concentric contraction (type 1), isometric contraction (type 2), and eccentric contraction (type 3). To measure muscle activation on the gluteus maximus contraction type, each position were maintained for 5 seconds with data collection taken place during middle three seconds. Muscle activation was measured in each position three times. Results: For the results of this study, there was no significant difference within three contraction patterns of the gluteus maximus (concentric, isometric, and eccentric) each both multifidus, both external oblique abdominis, and gluteus maximus. And there was no significant difference among both multifidus, both external oblique abdominis, and gluteus maximus each hip extension contraction type. Conclusions: These findings suggest that specific contraction types of the gluteus maximus does not lead to a more effective activation of the multifidus, external oblique abdominis, and gluteus maximus.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.6
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• pp.631-637
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• 2013

The characteristics of involute gear pump with eccentric gap between gear tip and housing have been studied in terms of volumetric flow rate and/or flow efficiency. The analysis has been done with FLUENT/R-13 employing with k-e model for the turbulent flow under the given conditions of rotational velocity, gap distance and outlet pressure. The effect of parameters continues to be shown for the eccentric gear as same as for the concentric gear such that the volumetric flow rate (volumetric efficiency) increases as the increases of rotational velocity and decrease of gap distance and of outlet pressure. In the meantime, the shape of pressure build-up appears to be exponentially increase as gap distance decreases at upstream position. The pressure is rapidly developing in the upstream and remains almost constant thereafter in the downstream of circumferential flow path. This typical characteristics becomes more profound as eccentricity increases. The pump performance for the eccentric gear pump with minimum gap distance shows better than its concentric counterpart. However, it shows not for the concentric pump with minimum gap distance. Therefore, the gap reduction due to eccentricity may be positive for pump performance.