• Journal of the Korean Arthroscopy Society
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• v.8 no.2
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• pp.98-102
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• 2004

Purpose: The purpose of this study was to make a report on the clinical prognosis of post traumatic lateral and posterolateral instability of the knee after LCL augmentation and popliteal tenodesis. Materials and Methods: The assessment was made among 21 cases who underwent augmentation of lateral collateral ligament(LCL) and popliteal tenodesis with allograft or artificial ligament (synthetic polyester, ABC ligament, Surgicraft, U.K.) at this Medical Center during the period from July 1996 to July 2003 and whose follow-up period was longer than one year. The authors recorded and analysed the physical findings (external rotation recurvatum test & posterolateral drawer test), stress roentgenograms(preoperative and postoperative) and Lysholm score. Results: The lateral and posterolateral instability of the knee were improved in 20 cases postoperatively, acccording to the clinical test and stress roentgenograms . Average Lysholm score was 52.5 preoperatively and 86.7 postoperatively .Conclusion: Our study found the surgery of lateral and posterolateral instability of the knee with augmentation of LCL and popliteal tenodesis using allograft or artiflcial ligament is simple technique. Taking these results into consideration, it seems to be one of effective methods of treatment.

• The Journal of Advanced Prosthodontics
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• v.12 no.6
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• pp.351-360
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• 2020

PURPOSE. The aim of the present study was to compare the stress distributions on the dental implants, abutments, and bone caused by different overdenture attachment types under functional chewing forces. MATERIALS AND METHODS. The 3D finite element models of the mandible, dental implants, attachment types, and prostheses were prepared. In accordance with a conventional dental implant supported overdenture design, the dental implants were positioned at the bone level in the canine teeth region bilaterally. A total of eight models using eight different attachment systems were used in this study. All the models were loaded to simulate chewing forces generated during the centric relationship (450 N), lateral movement (400 N), protrusive movement (400 N), and also in the presence of a food mass unilaterally (200 N). Stress outputs were obtained as the maximum principal stress and the equivalent von-Mises stress. RESULTS. In all attachment types, higher stress values were observed in the abutments, dental implants, and bone in the magnet attachments in different loading conditions. The highest stress values were observed among the magnet systems in the components of the Titanmagnetics model in all loading conditions (stresses were 15.4, 17.7, and 33.1 MPa on abutment, dental implant, and bone, respectively). The lowest stress value was observed in the models of Zest and O-Ring attachments. CONCLUSION. The results of the present study implied that attachment types permitting rotation and tolerating various angles created lower stresses on the bone, dental implants, and abutments.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.285-291
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• 2003

An experimental method to measure Q-parameter in-situ is described. The basic idea comes from the fact that the side necking near a crack tip indicates the loss of stress triaxiality, which can be scaled by Q. From the out-of-plane displacement and the in-plane strain near the surface of side necking, stress field averaged through the thickness is calculated and then Q is determined from the difference between the stress field and the HRR field corresponding to the identical J-integral. To prove the validity, three-dimensional finite element analysis has been performed for a CT configuration with side-groove. Q-value which was calculated directly from the near-tip stress field is compared with that determined by simulating the experimental procedure according to the proposed method, that is, the Q-value determined from the lateral displacement and the inplane strain. Also, the effect of location where the displacement and strain are measured is explored.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.260-263
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• 2005

In this study, we analyzed the plantar shear stress and pressure of diabetic foot patients during walking by using in-shoe local shear force and plantar pressure measurement system. Twelve normal subjects and three diabetic foot patients with diabetic neuropathy in lateral heel were participated in this study. The center of pressure in diabetic foot patients moved more medially and directed toward 1st, 2nd metatarsal heads and hallux during late stance period, making pressure at the medial heel and 2nd metatarsal head significantly higher than in the normal. Shear stress at the heel were changed significantly in early stance and the magnitude of shear stresses in each metatarsal head were also changed. Further studies would be very helpful to design foot orthoses in patients with diabetic neuropathy or other diseases.

• Steel and Composite Structures
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• v.49 no.3
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• pp.271-280
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• 2023

In this study, the three-dimensional finite element method is used to analyze the behavior of corner cracks in finite-thickness plates repaired with a composite patch. The normalized stress intensity factor at the crack front is used as fracture criterion. Comparison of stress intensity factor values at the internal and external positions of repaired quarter-elliptical corner crack was done, for three repair techniques. The influence of mechanical and geometrical properties of the adhesive layer and the composite patch on the variation of the stress intensity factor (SIF) at the crack-front was highlighted. The obtained results show that the application of double patch leads to a remarkable reduction of SIF at the crack front, compared to facial and lateral repairs.

• Journal of Korean Society of Steel Construction
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• v.16 no.2 s.69
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• pp.215-224
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• 2004

The inelastic lateral-torsional buckling behavior of the beam-columns and the columns was investigated in this paper. The energy method was deployed to study the inelastic buckling behavior of the beam-columns and columns. which requires the iterative solution of a fourth-order eigenproblem. Hitherto, the patterns of residual stress that satisfies the I-section manufacturing in Korea is not available, therefore the pattern of residual stress used in this study is a 'well-known' simplified pattern. The simplified pattern of the residual stresses is incorporated with the flow theory of plasticity to model the inelastic response. Firstly, this study investigates the inelastic lateral-torsional buckling behavior of the I-section beam-columns under a concentric axial compressive force and uniform bending, and the effect of residual stress on the inelastic buckling behavior of beam-columns is studied. The study is then extended to the inelastic buckling of the columns by eliminating a bending moment. These results are compared it with the design method in the Korean Steel Designers Manual (KSDM 1995). This study has found that design method in KSDM (1995) is excessively conservative.

• The Journal of Korean Academy of Prosthodontics
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• v.26 no.1
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• pp.153-169
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• 1988

There is a little scientific documentation reporting the stress, distribution to the edentulous mandible by different concepts of occlusal scheme. So, this study was to investigate the hypothesis that the magnitude and distribution of the occlusal stresses, transmitted through a mandibular complete denture base to the edentulous mandible, would be influenced by the lingualized occlusion. This investigation was performed to analyze the stresses induced in a three-dimensional photoelastic edentulous mandible, when a load is applied to the denture arranged into lingualized occlusion in centric relation, lateral and protrusive functional position. The mounted denture on a Dentatus Type ARO articulator was loaded in a pure vertical direction with 15kgs on the center of articulator in each case and the stresses were frozen into epoxy edentulous model at $127^{\circ}C$ in the stress freezing furnace. The stress-frozen epoxy models were sliced with diamond disc saw into 4mm thick. The slices were examined with a circular polariscope. The results were as follows: 1. In centric relation, the stresses were low at anteriors, and gradually increase to the premolar, molar area and highest at the first molar and gradually decrease from the second molar and lowest at the retromolar pad region. The lingual side showed higher stresses than labiobuccal side. 2. In lateral functional position, the working side showed higher stresses than the balancing side. In working side, the lingual side showed higher stresses than the buccal side and in balancing side, the buccal side showed higher stresses than the lingual side. 3. In protrusive position, stress distribution was symmetrical on the posteriors and the stresses were concentrated at the labial side of the anteriors.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1243-1251
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• 2013

The purpose of this study is to investigate the influence of initial clamping force of tension clamp on the performance of an elastic rail fastening system used in sharp curve track. In this study, the initial clamping force and the increasing lateral wheel loads were conducted in the analytical and experimental study, i.e., finite element analysis, laboratory and field test. Using the analytical and experimental results, the performance of the tension clamp was investigated. It was found that the stress of tension clamp depends on the initial clamping force. Therefore the initial clamping force appeared to directly affect the compression stress of the tension clamp. It was found that the compression stress of tension clamp was transferred to the tensile stress by applied the lateral wheel load in service sharp curve track. Further, it was concluded that the initial clamping force was applied on the strengthening force for the tension clamp and then the appropriate initial clamping force was important to ensure a stable performance and long term endurance of tension clamp.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.2
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• pp.176-183
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• 2010

In the steel deck box girder bridges, the deck is composed of deck plate, longitudinal and lateral direction ribs. The bridge, that is considered in this study, has been used for about 40 years and, recently, several cracks were found in the connection area of U-ribs. Further, additional cracks were occurred after some lateral rib plates and longitudinal frames were attached for the purpose of reinforcement. Therefore, the connection method in the U-ribs reinforcement was changed from the bolting to the weldment to get rid of stress concentration and further cracking. In this study, the stress in the U-ribs connection was analysed numerically and variable amplitude stress for the real traffic loads was measured experimentally before and after the frame reinforcement. Finally, the effects of reinforcement method were investigated and discussed.

• Proceedings of the Materials Research Society of Korea Conference
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• 1996.11a
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• pp.114-114
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• 1996