• Journal of Korea Society of Waste Management
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• v.35 no.8
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• pp.709-720
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• 2018

Since the import ban of plastic waste in China has been enforced, plastic wastes were not properly collected and recycled in Korea. Hence, the management strategies for plastic waste in Korea should be improved by examining the regulations and policy in developed countries such as United States, Japan, EU and United Kingdom. The management strategy for the recycling cycle should be implemented to expand the labeling system of separation and discharge, reduce the consumption of plastic products, automate the separation and sorting method in recycling facilities, and improve the economical efficiency of the recycling cycle. The concept of residual waste (secondary waste) in the material flow analysis should be implemented to identify the shortage point in the plastic waste stream. Finally, the cooperation with international communities is required for a transboundary movement of plastic waste, which includes participation at the working group of international standards to recycle plastic waste.

• Journal of Ocean Engineering and Technology
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• v.16 no.6
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• pp.44-48
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• 2002

In lateral ground flow, slope stability, and land slide problems, H-piles have often been used, on a horizontally deforming ground, to prevent the failure of mass of soil in a downward and outward movement of a slope. Here, theoretical equations are derived to estimate the lateral force, assuming that the Mohr-Coulomb's plastic states occur in the ground, just around H-piles. In this study, some model experiments were performed to check the lateral forces determined from theoretical equations, using several pile widths, heights and various interval ratios between H-piles for sand specimens. The solution of the theoretical equation, derived from previous studies, showed reasonable characteristics for constants of soil, as well as for the interval, widths, and heights of H-Pile.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.1
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• pp.32-36
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• 2010

The purpose of this study was to evaluate the clinical outcomes of patients with temporomandibular joint disorder before and after performance of arthrocentesis and stabilization splint therapy. The subjects of this study were 33 patients with limited mouth opening or pain or joint effusion who visited the Department of Oral and Maxillofacial Surgery, St Mary's Hospital, Catholic University of Korea. The arthrocentesis was performed and the stabilization splint was worn immediately after the arthrocentesis. Comparing the clinical outcomes of treatment at the times of first medical examination, 3 months and 6 months later on treatment. The results are as follows; 1. Statistically significant increase in the amount of maximum mouth opening occurred 3 months and 6 months later on treatment. 2. Statistically significant decrease in the average value of pain on test measured by VAS during maximum mouth opening, protrusive movement, right lateral movement, left lateral movement occured 3 months and 6 months later on treatment. The results suggested that arthrocentesis and stabilization splint therapy provide a improvement on patients with temporomandibular joint disorder when the exact diagnosis were provided.

• The korean journal of orthodontics
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• v.21 no.3
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• pp.543-560
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• 1991

Practitioners are aware of the presence of friction between bracket system and archwire during sliding movement of teeth. Clinically a mesiodistally applied force must exceed the frictional force to produce a tooth movement. The objective of this study were to determine, on a dry condition, changes in magnitude of friction with respect to load, 3rd order inclination (Torque), archwire materials and ligature type. Three wire alloys (Stainless Steel, TMA, NiTi) in two wire sizes (.016, .016x, .022 inch) were examined respect to two bracket system (Straight, Standard), and two ligature type (Metal, Plastic ligature) at three levels of load (100g, 150g, 200g). The results were as follows; 1. Frictional resistance was found to increase with increasing load for S.S., TMA, NiTi. 2. The straight bracket system was exhibited more frictional force than standard bracket system for .016x, .022 S.S. tightly ligated metal ligature. But, torque difference did not increase friction for loose metal ligature & plastic ligature. 3. Regardless of the ligature type, torque and load, stainless steel wire sliding against stainless steel exhibited the lowest friction, and TMA sliding against stainless steel exhibited the highest friction. 4. The loose stainless steel ligature generated lower frictional resistance than plastic ligature in all experimental groups. 5. The following factors affected friction in decreasing order; wire material ligature type, and load.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.41
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• pp.48.1-48.7
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• 2019

Background: Soft tissue asymmetry such as lip canting or deviation of the philtrum is an important influencing factor for unbalanced facial appearance. Lip canting could be improved by the correction of the occlusal canting or positional change of the mentum. Although there are many studies about changes of lip canting, however, postoperative changes of philtrum deviation have not been yet reported. In this study, we investigate the positional change of the philtrum after orthognathic surgery and influencing factors. Methods: Positional change of the philtrum was evaluated in 41 patients with facial asymmetry who underwent bimaxillary surgery, in relation to other anatomical soft tissue landmarks using a frontal clinical photo. The surgical movement of the maxillary and mandibular dental midline and canting were measured in postero-anterior cephalogram before and 1 day after surgery. The same procedure was repeated in patients with more than 1.5 mm perioperative change of the mandibular dental midline after bimaxillary surgery. Results: Maxillary dental midline shifting and canting correction did not have a significant correlation with lateral movement of the philtrum midline. However, the mandibular shift had a statistically significant correlation with a lateral movement of the philtrum (p < 0.05) as well as other linear parameters and angle values. Conclusion: The horizontal change of the philtrum is influenced by lateral mandibular movement in patients with facial asymmetry, rather than maxillary lateral movement.

• Journal of the Korean Geotechnical Society
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• v.18 no.5
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• pp.55-65
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• 2002

Model tests were performed to investigate the mechanism of lateral earth pressure on a buried pipe, which was installed in a plastic flowing soil mass undergoing lateral movement. On the basis of failure mode tests, the equation of lateral earth pressure to apply Maxwell's visco-elastic model was proposed to consider the soil deformation velocity. Through a series of model tests of differential soil deformation velocity, lateral earth pressure of theoretical equation was compared with experimental results. When lateral soil movement was raised, the lateral earth pressure acting on buried pipe increases linearly with the soil deformation velocity. It shows that the lateral earth pressure on buried pipe is largely affected by soil deformation velocity. When plastic soil movement was raised, lateral earth pressure predicted by theoretical equation showed good agreement with experimental results. Also, coefficient of viscosity by theoretical equation had a good agreement with direct shear test results.

• Proceedings of the Korean Geotechical Society Conference
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• 1996.10a
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• pp.337-344
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• 1996

• The monthly packaging world
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• s.319
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• pp.48-58
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• 2019

• Archives of Plastic Surgery
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• v.33 no.4
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• pp.449-453
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• 2006

Purpose: Perceiving the experience that $MRD_1$ is increased after small-incision double-eyelid operation, it has been statistically verified the improvement of $MRD_1$ retrospectively. Therefore, we suggest new interpretation for Korean-specific small eye and more definite classification for ptosis. Methods: In operation, we made 3 small incisions according to the line designed on upper eyelid and removed some soft tissues including connective tissues. Then, figure-of-8 continuous buried ligation was performed through the incision windows. This study is a retrospective study, measures $MRD_1$ changes and excursion distance change of eyelid margine and eyebrow using pre-and post-operative photos of 14 patients. Results: Postoperative photos were taken on the 4th day and all of 14 patients had an improvement in $MRD_1$ statistically. The excursion distance of upper eyelid was improved in half of patients, though not in the range of statistical verification. It was statistically confirmed that the movement of eyebrow was reduced after operation. Conclusion: It is thought that $MRD_1$ improvement without any operation on levator complex means that soft tissue including connective tissue eliminated in operation restricts the movement of upper eyelid. It is defined such factors as burden factors and such phenomenon as burdened eyelid. It is thougt that Korean's small eye is mainly burdened eyelid and cosmetic improvement may be obtaind even by removing such burden factors.

• Archives of Plastic Surgery
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• v.34 no.4
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• pp.436-440
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• 2007

Purpose: TRAM flap surgery has settled down as a common method for breast reconstruction after mastectomy. We investigated how TRAM flap surgery influences on the patients' physical movement capability by observing their capability of sit-ups as well as exercises they usually enjoy. Methods: A total of consecutive 375 patients were investigated who had breast reconstruction with unilateral pedicled TRAM flap surgery at Asan Medical Center from July 2001 to August 2005. The patients were asked to sit up right before the surgery and do it again 6 months later and 1 year later. 221 patients were followed up 6 month after the surgery. And 132 patients were followed up 1 year after the surgery. In addition, 155 patients who used to exercise before the surgery were also asked to show us the change in their physical movement capability one year after their surgery. Results: 139 patients showed decrease in the counted number of sit-ups, 48 increase, and 34 showed no change between 6 months in the first group of 221 patients. Among the second group of 132 patients, 64 showed decrease, 39 increase, and 29 no change a year later. There was a statistical significant decrease in the number of sit-ups between pre-operation and six months later and between pre-operation and one year later. According to the research on the exercise that 155 patients participated, 3 of them showed improvement in athletic ability, 7 showed decrease, while the rest, 145 patients, showed no change at all. Conclusion: Considering no difference in usual exercise ability, some patients' increase in the number of sit-ups and the effect of anticancer treatment, we found that the loss of abdominal wall function on this research is not too serious to exclude TRAM flap surgery in the field of breast reconstruction