• The Journal of Korean Academy of Prosthodontics
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• v.47 no.2
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• pp.191-198
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• 2009

Statement of problem: Ceramics have been important materials for the restoration of teeth. The demands of patients for tooth-colored restorations and the availability of various dental ceramics has driven the increased use of new types of dental ceramic materials. Improved physical properties of theses materials have expanded its use even in posterior crowns and fixed partial dentures. However, ceramic still has limitation such as low loading capability. This is critical for long-span bridge, because bridge is more subject to tensile force. Purpose: The wire reinforced ceramic was designed to increase the fracture resistance of ceramic restoration. The purpose of this study was to evaluate the fracture resistance of wire reinforced ceramic. Material and methods: Heat pressed ceramic(ingot No.200 : IPS Empress 2, Ivoclar Vivadent, Liechtenstein) and Ni-Cr wire(Alfa Aesar, Johnson Matthey Company, USA) of 0.41 mm diameter were used in this study. Five groups of twelve uniform sized ceramic specimens(width 4 mm, thickness 2 mm, length 15 mm) were fabricated. Each group had different wire arrangement. Wireless ceramic was used as control group. The experimental groups were divided according to wire number and position. One, two and three strands of wires were positioned on the longitudinal axis of specimen. In another experimental group, three strands of wires positioned on the longitudinal axis and five strands of wires positioned on the transverse axis. Three-point bending test was done with universal testing machine(Z020, Zwick, Germany) to compare the flexural modulus, flexural strength, strain at fracture and fracture toughness of each group. Fractured ceramic specimens were cross-sectioned with caborundum disc and grinded with sandpaper to observe interface between ceramic and Ni-Cr wire. The interface between ceramic and Ni-Cr wire was analyzed with scanning electron microscope(JSM-6360, JEOL, Japan) under platinum coating. Results: The results obtained were as follows: 1. The average and standard deviation in flexural modulus, flexural strength and fracture toughness showed no statistical differences between control and experimental groups. However, strain was significantly increased in wire inserted ceramics(P<.001). 2. Control group showed wedge fracture aspects across specimen, while experimental groups showed cracks across specimen. 3. Scanning electron microscopic image of cross-sectioned and longitudinally-sectioned specimens showed no gap at the interface between ceramic and Ni-Cr wire. Conclusion: The results of this study showed that wire inserted ceramics have a high strain characteristic. However, wire inserted ceramics was not enough to use at posterior area of mouth in relation to flexural modulus and flexural strength. Therefore, we need further studies.

• The Journal of the Convergence on Culture Technology
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• v.1 no.2
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• pp.77-83
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• 2015

The purpose of this study is to prove the increase of range of motion of shoulder joint in the patients with shoulder adhesive capsulitis by applying the vibratory stimulation. In terms of subjects of the study, the experimental group 15(4 male, 11 female)and the control group 15(5 male, 10 female) were divided. The measurement of the shoulder range of motion was taken by measuring the degrees of flexion, abduction, and external rotation with a goniometer from pre treatment to one to four weeks. The results were as follows : In the experimental group and control group, there was the statistical significance in the range of motion of the shoulder flexion, abduction, and external rotation during four weeks. In summary, the vibratory stimulation are effective interventions for improving shoulder adhesive capsulitis, patient's range of motion of shoulder joint.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.117-117
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• 2012

Dyeing and fastness properties of 800nm sea-Island type PET nanofilament fabrics have been investigated. The dye uptake of nanofilament commended at lower temperatures and showed faster rate of dye uptake. The build up and wet fastness propertied of disperse dye on nanofilament were relatively poor since the more dye was needed to achieve a given depth of shade due to the large surface area.

• Magazine of the Korea Concrete Institute
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• v.6 no.3
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• pp.173-179
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• 1994

Test results to evaluate the rr~echanical properties of epoxy-coated reinforcing bars are described. Tests include adhesion, impact, bend, and abrasion test of epoxy coating to reinforcing steel, specified in relevant KS and ASTM standards. Three nomnal thicknesses of epoxy coating, $120{\mu}m$, $220{\mu}m$, $300{\mu}m$ are used. The results show good adhesion and abrasion resistance satisfying the requirements. The results also show faily good bendability. However, the thicker the coating, the weaker the adhesion is. Impact resistance is in the tolerable range, but it is recorrmerided that careful treatments are required during handling of epoxy-coated bars. From the results, epoxy-coated bars, with a coating thickness ranging from $150{\mu}m$ to $300{\mu}m$, should well perform for fabrication in field construction.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.3
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• pp.207-214
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• 2016

The aim of this study was to evaluate Influence on intra-limb coordination in individuals wearing knee brace during walking. Seven healthy male adults ($32.3{\pm}2.7$ years old, $175.2{\pm}3.8cm$, $76.2{\pm}8.7kg$) participated. They wore knee brace or didn't wear any knee brace and were asked to walk along a 10 m long walkway. Spatiotemporal parameters, angles of the lower limbs, and intra-limb continuous relative phase (CRP) were measured and calculated. No differences of spatiotemporal parameters were shown (all p > 0.05). There were no changes in the angle and its range of motion (ROM) in the hip for the subjects as wearing knee brace, while ROM ($65.5{\pm}3.7^{\circ}$ vs. $60.5{\pm}3.5^{\circ}$, p < 0.05) of the angle and maximum flexion angles (stance: $31.9{\pm}4.6$ vs. $25.6{\pm}5.5$, swing: $76.7{\pm}3.1$ vs. $68.9{\pm}3.4$, all p < 0.05) in the knee significantly decreased. No changes in ROM of angle in the ankle were shown, whereas maximum dorsiflexion decreased ($22.4{\pm}2.6$ vs. $19.2{\pm}2.1$, p < 0.05) and maximum plantarflexion increased ($9.5{\pm}3.0$ vs. $15.7{\pm}2.2$, p<0.05). There were no changes in most of CRP between joints. CRP between the hip and knee joints decreased ($93.0{\pm}7.8$ vs, $84.7{\pm}4.9$, p < 0.05). Most of CRP standard deviation increased (between the hip and ankle joint during swing: $25.1{\pm}6.7$ vs. $32.4{\pm}1.9$, between the knee and ankle joint during stance: $46.0{\pm}12.9$ vs. $80.1{\pm}31.1$, between the knee and ankle joint during swing: $34.5{\pm}4.1$ vs. $37.6{\pm}3.1$, all p < 0.05). These results indicated that wearing knee brace affected joint angle and intra-limb coordination, but less affected gait features.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.67-75
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• 2009

Purpose: This study evaluated the clinical outcomes of debridement arthroplasty using the posteromedial approach in elbow joints with pain and bony limitation of motion. Materials and Methods: This study involved 16 elbows in 16 patients with pain and bony limitation of motion, which were treated by debridement arthroplasty using the posteromedial approach from March 2005 to March 2008. The mean follow up period was 27.6 (13~52) months. The clinical outcomes were analyzed using the Visual Analogue Scale(VAS) for pain scale, the preoperative and postoperative range of motion and the Mayo Elbow Performance Scores(MEPS). Results: The VAS was decreased significantly from a preoperative mean of 4.5 to a postoperative mean 1.1 (p<0.001). The average arc of motion improved significantly from $61.6 (0~90)^{\circ}$ preoperatively to $109.4 (80-120)^{\circ}$ postoperatively (p<0.001). The MEPS also improved significantly from 59.4 to 85.6 postoperatively (p<0.001). There were no complications, such as hematoma and elbow instability. Conclusion: Debridement arthroplasty using the posteromedial approach is a useful surgical procedure in the elbow joint with pain and bony limitation of motion, where all compartments can be debrided, the ulnar nerve can be manipulated easily and damage to the medial collateral ligament can be minimized.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.81-90
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• 2018

The purpose of this study is to evaluate the effect of downward speed limit of urban arterial roads at 29 sites in Busan Metropolitan Police Agency to reduce road traffic accidents from '10 to '15. As a result of analyzing the traffic accidents occurred for 1~3 years after the decrease in the speed limit, the number of traffic accidents decreased by 3.09% and the number of injured persons decreased by 8.76%, but the number of deaths decreased by 36.73% The results of this study are as follows. The average speed reduction rate of 6.31km/h was decreased by investigating the change of the vehicle speed before and after the downward speed limit, and the change of average speed was statistically significant in most of the sections. The rate of compliance with the speed limit increased by 10.26% p, which is considered to have greatly improved overall traffic safety. A survey conducted by residents near the target area with a lower speed limit showed that 57.9% of the respondents felt the driving speed of the vehicle was lowered. However, this project was focused on vehicles with limited speed road signs and traffic safety signs, Only 25.8% of respondents said walking safety was improved. In the future, it is necessary to consider the safety of pedestrians by improving roads around roads such as road curvature and separation. In addition, there is a clear positive result in terms of decreasing the fatal accidents in the downward speed limit zone of Busan Metropolitan Subway. However, more detailed analysis is needed for the 29 accidents. Therefore, it is expected that traffic practitioners will be able to utilize it as a basis to increase the accident reduction effect by setting an appropriate speed limit based on the easy and objective grounds.

• Tuberculosis and Respiratory Diseases
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• v.57 no.5
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• pp.484-488
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• 2004

In adults, aspiration of foreign bodies into tracheobronchus is sometimes presented atypically, mimicking chronic pulmonary diseases such as bronchial asthma, pneumonia, or empyema, especially without notice of aspiration or choking. In such cases, diagnosis and adequate treatments are often delayed. Suspicion of foreign body aspiration and computed tomography and bronchoscopic examination make correct diagnosis more early. We report a case of bronchial foreign body, which had been misdiagnosed as bronchial asthma with wheezing in the whole lung filed, and reversible airway obstruction in the spirometry.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.84-88
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• 2011

Purpose: We report here on two cases of calcific tendinitis at the origin of the common extensor tendons of the forearm. Materials and Methods: A 42 year-old female complained of left elbow pain and flexion contracture. After obtaining the simple radiographs and MRI, surgical excision of the calcific deposits was done under the diagnosis of calcific tendinitis. A 25 year-old female complained of right elbow pain and a limited range of motion. Simple radiographs showed a calcific deposit just distal to the lateral epicondyle, and then she was managed with extracorporeal shock wave therapy. Results: The pain disappeared completely and both patients regained a full range of motion after treatments. Conclusion: Calcific tendinitis at the origin of the common extensor tendons of the forearm should be included in the differential diagnosis of the lateral elbow diseases that cause pain and a limited range of motion.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.75-81
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• 2006

슬관절 전치환술은 관절염이나 사고로 인해 일상적인 활동의 제약을 받는 환자의 슬관절을 인공 관절로 대체함으로써 본래의 기능을 복원하고자 하는 수술이다. 이 수술은 인공 관절의 위치 및 정렬에 매우 민감하게 영향을 받기 때문에 수술이 잘못되는 경우 정렬 이상으로 인한 해리, 삽입물의 파손, 인공 슬관절 주위 골절, 슬개골 탈구, 굴곡 각도의 제한 등의 증상이 발생할 수 있다. 현재의 인공 관절은 임상에 적용되는 다양한 인공 관절 중에서 적당한 형상의 관절을 선택하여 시술되고 있지만 환자의 골 형상에 정확히 일치하는 인공 관절 선택의 어려움 때문에 종종 시술 후 부작용이 발생한다든지 심지어는 재수술을 해야 될 경우도 발생하게 된다. 본 논문은 Mechanical CAD 소프트웨어인 CATIA에서 제공하는 절단, Assembly, Analysis, Kinematic Simulation 기능 등을 이용하여 가상 수술을 수행하는 과정을 보여준다. 슬관절 전치환술 과정을 그대로 재현하여 절단량과 절단각을 결정하고 환자의 골격 형상에 적합한 최적의 인공 관절을 실제 수술 전에 미리 선정할 수 있다. CAD 시스템을 이용함으로써 외과의들이 실제 수술 시에 시행착오법을 통해 인공 관절을 선택하는 과정을 줄이고 수술의 정확도를 높일 수 있다. 향후 ADAMS나 ANSYS와 연계하여 수술 후 동작이나 하중을 분석할 수 있으며, 수술 과정에 대한 교육용으로 활용될 수 있다.