• Journal of the Korean Society for Precision Engineering
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• v.23 no.12 s.189
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• pp.103-110
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• 2006

The rail clamp is very important device to prevent that a container crane slips along a rail due to the wind blast as well as to locate the crane in the set position during an operating mode. Recently, the design wind speed criteria were intensified from the wind speed of 16m/s to 35m/s during an operating mode, and from 50m/s to 75m/s during a stowed mode in Korea, according to the 'Inspection Criteria for Facilities and Equipments in Port' reformed after typhoon 'Maemi'. In order to design the wedge type rail clamp for the reinforced design wind speed criteria of 35m/s, we carried out the finite element analysis of the rail clamp with respect to the wedge angle, and analyzed the relationship between the wedge angle and the sliding distance of the rail clamp.

• Journal of Korean Foot and Ankle Society
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• v.9 no.1
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• pp.59-63
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• 2005

Purpose: To present the procedure and results of dorsal wedge osteotomy fixated by bioabsorbable polyglycolide pins for the treatment of symptomatic Freiberg's disease. Materials and Methods: From January 1997 to December 2002, six patients with Freiberg's disease underwent dorsal wedge osteotomy of the metatarsal neck to bring the healthy plantar part of the metatarsal head into articulation. Bioabsorbable polyglycolide pins were used for the fixation and short-leg walking cast was applied for 4 weeks. Results: All patients returned to full daily activities without pain in three months after the operation. Radiographically, solid healing of the osteotomy was observed at average ten weeks. The active range of motion of the metatarsophalangeal joint increased by a mean gain of 30 degrees, and no complication such as displacement, osteolysis or sinus formation was observed. Conclusion: Dorsal wedge osteotomy fixated by bioabsorbable pins for patients with symptomatic Freiberg's disease is effective procedure that provides relatively early range of motion exercise and avoids second procedure for implant removal.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.527-534
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• 2000

136 cut slopes which extends from Namyangju to Chunchon city along the 46th national highway were investigated to analyze the influence factors affecting slope instability. Geologic and geotechnical conditions were examined and the detailed investigation were carried out for fifty five failed slopes. failure mode (wedge failure, planar failure, circular failure, sheet eroison and rock falls) are examined with respect to slope inclination, rock type, weathering grade and discontinuity patterns. It is suggested that the failure modes and their dimensions have relations to the morphology and geologic conditions of the slopes. Wedge failure has highest is the most frequent failure mode and falls, sheet erosions, planar failures and circular in descending order of failure percentage. Wedge failure is most dominant failure type over all lithology except quartzite formation. In slopes of well foliated and banded gneiss, failure ratio of wedge is up to 50% ca. Failure ratio(number of rock fall/number of total failure) of rock fall increases with increase fo slope inclinations and decrease of weathering grade. Dimension analyses of failed slopes shows wedge and circular failure has higher value of D/L and D/H than planar failure and sheet erosion.

• Journal of Chest Surgery
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• v.27 no.4
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• pp.328-330
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• 1994

Brachial plexus injury developing after axillary thoracotomy is an uncommon complication. But if it occurs, it may cause annoying events. We recently experienced 2 patients who developed brachial plexus injury after wedge resection by axillary thoracotomy . The first patient was a 22 year-old man with right spontaneous pneumothorax . After wedge resection of the right upper lung by axillary thoracotomy, he complained total paralysis of the right arm. An electromyogram was obtained at 7 days after operation, with the confirmation of brachial plexus injury. He was discharged at 22days after operation and brachial plexus injury was completely recovered 4 months after discharge. The second patient was a 17 year-old man with recurrent right pneumothorax. He underwent wedge resection of the right upper lung by axillary thoracotomy. Electromyogram confirmed the diagnosis of brachial plexus injury in the immediate postoperative period. He was discharged at 15 days after operation and brachial plexus injury was recovered 2months after discharge.Brachial plexus injury after axillary thoracotomy is caused by stretching around the clavicle and tendon of pectoralis minor by fixation of the abducted arm to the frame. Thus, when we perform wedge resection by axillary thoracotomy, we must avoid over-stretching of the brachial plexus in positioning. If brachial plexus injury develops, immediate attention and management with close rapport are important to avoid possible medicolegal problems.

• Journal of Korean Neurosurgical Society
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• v.46 no.3
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• pp.195-198
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• 2009

Objective : Medpor porous polyethylene was used to reconstruct small bone defects (gaps and burr holes) along a craniotomy bone flap. The feasibility and cosmetic results were evaluated. Methods : Medpor Craniotomy Gap Wedges, V and T, were designed. The V implant is a 10 cm-long wedge strip, the cross section of which is an isosceles triangle with a 4 mm-long base, making it suitable for gaps less than 4 mm after trimming. Meanwhile, the Medpor T wedge includes a 10 mm-wide thin plate on the top surface of the Medpor V Wedge, making it suitable for gaps wider than 4 mm and burr holes. Sixty-eight pterional craniotomies and 39 superciliary approaches were performed using the implants, and the operative results were evaluated with respect to the cosmetic results and pain or tenderness related to the cranial flap. Results : The small bone defects were eliminated with less than 10 minutes additional operative time. In a physical examination, there were no considerable cosmetic problems regarding to the cranial bone defects, such as a linear depression or dimple in the forehead, anterior temporal hollow, preauricular depression, and parietal burr hole defect. Plus, no patient suffered from any infectious complications. Conclusion : The Medpor Craniotomy Gap Wedge is technically easy to work with for reconstructing small bone defects, such as the bone gaps and burr holes created by a craniotomy, and produces excellent cosmetic results.

• Journal of Gastric Cancer
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• v.11 no.4
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• pp.225-229
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• 2011

Purpose: Laparoscopic wedge resection of gastric submucosal tumor may be difficult in case of the endophytic mass or the mass located unreachable area such as cardia, and intragastric approach can be useful. We would present the experiences of the intragastric wedge resection. Materials and Methods: There were 7 patients diagnosed as gastric submucosal tumor and underwent the intragastric wedge resection at Surgery, Chungnam National University Hospital. We reviewed medical record. Results: There were 3 male and 4 female. Mean age was 65 years-old (57~73). Mean body mass index was 26.28 kg/$m^2$ (21.28~35.30). Location of lesions was 4 cardia, 2 fundus and 1 midbody, respectively. Mean operation time was 83.6 minutes (70~105). All patients were healed without any complication. Mean postoperative hospital stay was 5.4 days (4~6). Mean size was 2.7 cm (2.3~3.8). Pathologic finding was 5 gastrointestinal stromal tumor and 2 leiomyoma. Conclusions: The single incision intragastric wedge resection of gastric submucosal tumor is feasible and acceptable, especially in mass of gastric upper part.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.3
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• pp.80-87
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• 2012

This paper suggests the slot wedge shape for reducing the cogging torque of a direct-drive permanent magnet synchronous generator for a bike. To consider easy coil winding, we applied a structure of open slot for the permanent magnet synchronous generator (PMSG). Because the cogging torque of PWSG with the open slot is very large, we are designed the appropriate specifications of the PMSG by selected the appropriate material of slot wedge and various slot wedge shapes. The prototype model is selected by design theory for reducing cogging torque and maximizing efficiency of PMSG. And the detailed structure design of the model was designed by the loading distribution method. The PMSG models were analyzed by finite element method. Finally, we have suggested appropriate material of slot wedges and its shape which has benefit to further reducing cogging torque and preventing decreasing of the generating power.

• Journal of the Korean Society of Propulsion Engineers
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• v.5 no.3
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• pp.10-18
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• 2001

In this paper, Supersonic jets impinging on a wedge were investigated in order to acquire fundamental design data for jet deflectors. Surface pressure distributions and pressure contours were obtained using a cold flow tester producing Mach 2 supersonic jets. Schlieren system was used to visualize the flow structure on the wedge surface. Numerical computations were performed and compared with the experimental results. Both results were in good agreement. The results showed that underexpansion ratio did not affect on the surface pressure distribution when the wedge is located at the nozzle exit. With increasing underexpansion ratio, pressure recovery decreased as the wedge is located farther from the nozzle exit. In the pressure contour, it was possible to locate the region where the peak pressure on the wedge surface was occurred.

• Journal of the Korean Institute of Gas
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• v.13 no.6
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• pp.1-8
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• 2009

This study pertains to damping device to reduce vibrational responses and shocks in multi-directions. To enhance the capability of disk spring damper which works for vertical vibration and shock, a multi-directional damper is proposed, which contains wedge system as well as disk spring stack. Wedge system converts horizontal load into vertical load. A mathematical model is proposed and investigated for the nonlinear behaviors of the disc spring damper containing wedge system. The results accord with the experimental results. Equivalent viscous damping in vertical and horizontal directions are found based upon energy dissipated.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.233-243
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• 2019

In this paper, numerical and experimental studies are performed to investigate the liquid impact on a free falling wedge. In the numerical simulation, the structure is assumed to be rigid and the elastic response is ignored. The fully nonlinear coupling between wedge and water is considered by an auxiliary function method based on the Boundary Element Method (BEM). At the intersection of the wedge surface and liquid surface, two coincident nodes are used to decouple the boundary conditions. The Eulerian free surface conditions in the local coordinate system are adopted to update the deformed free surface. In the experiments, five pressure sensors are fixed on each side of the wedge which is released from an experimental installation. Steel and aluminum wedges that have different structural elasticity are used in the experiments to investigate the influence of structural elasticity on the impact force. Numerical results are compared with experimental data and they agree very well. The influence of fluid gravity, body mass, initial entry speed and deadrise angle on the impact pressure are further investigated.