• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.03a
• /
• pp.896-901
• /
• 2009

A Soil Nail is a structural element which provides load-transfer to the ground in excavation reinforcement applications. The nail may simply consist of a steel tendon, but most commonly the tendon is encapsulated in a cement grouted body to provide corrosion protection and improved load- transfer to the ground. For temporary excavation support in a congested urban area, the steel bar of Soil Nails should be removed to get permission of the private land to install Soil Nails. Several removable nail systems were developed and evaluated by pull-out load tests. The Soil Nail pull-out tests were performed on five nails installed in soft and hard rock at a 00 housing-redevelopment area in seoul. Two nails are plastic socket type and two are complex socket type mixed steel and plastic. The nail was 0.1mm in diameter, 4m long. In this study verification tests, and steel bar removing tests of plastic socket type nails and complex socket type nails were performed and presented.

• Structural Engineering and Mechanics
• /
• v.85 no.3
• /
• pp.407-417
• /
• 2023

Precast assembled bridge piers with hybrid connection (PASP) use both tendons and socket connections. To study the seismic performance of PASP, a full-scale in-situ test was performed based on an actual bridge project. The elastic-plastic fiber model of PASP was established using finite element software, and numerical analyses were performed to study the influence of prestress degree and socket depth on the PASP seismic performance. The results show that the typical failure mode of PASP under horizontal load is bending failure dominated by concrete cracking at the joint between the column and cushion cap. The cracking of the pier concrete and opening of joints depend on the prestress degree and socket depth. The prestressing tendons and socket connection can provide enough ductility, strength, restoration capability, and bending strength under small horizontal displacements. Although the bearing capacity and post yield stiffness of the pier can be improved to some extent by increasing the prestressing force, ductility is reduced, and residual deformation is increased. Overall, there are reasonable minimum socket depths to ensure the reliability of the socket connection.

• Design & Manufacturing
• /
• v.11 no.2
• /
• pp.9-14
• /
• 2017

The design and manufacturing tehcnology of IC sockets beyond 0.3mm pitch were presented. We compared the developed IC socket with the conventional one especially on the core metal-insulation part. Advanced machining techniques were employed to provide high precision. Our wire electrodischarge machining and high speed machining centers were able to maintain the micro-scale precision. We performed an injection molding analysis using a commercial analysis tool to predict the performance of the developed IC socket. We found that the solidification of the plastic resin and the high level of the clamping force are responsible for the defects such as incomplete filling and short shot. From these results, we modified the IC socket and successfully remove the defects. We were also able to find out that the new design socket needs less maintenance cost.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.27 no.3
• /
• pp.238-247
• /
• 2005

The placement of different graft materials and/or the use of occlusive membranes to cover the extraction socket entrance are techniques aimed at reducing alveolar ridge resorption and enhancing bone formation. However, in spite of its clinical advantage, the use of graft materials in fresh extraction socket has been questioned because particles of the grafted material have been found in alveolar sockets with fibrous union. The purposes of this study were to evaluate whether alveolar ridge resorption following tooth extraction could be reduced and bone formation could be enhanced by the application of absorbable gelatin spongy or gelatin spongy soaked with platelet rich plasma(PRP) used as a space filler in clinical and radiographic aspects. Eighty patients who were scheduled for extraction of both third molars were participated and carried out by one experienced surgeon. Following extraction of teeth, one extracted socket were treated with gelatin spongy as an experimental group A and the other were treated with gelatin spongy and PRP as an experimental group B. The routine extracted socket were healed without any treatment as a control group. From the period of extraction to 12 weeks postoperatively, we examined the clinical course and radiographic evaluation on socket at regular interval. Both experimental groups showed faster wound healing process than control clinically. Vertical gingival height of the extraction socket were less changed statistically in both experimental groups than control. The horizontal width change of the extraction socket were not significant statistically in any group. Radiographic changes of the alveolar bone height were less changed in both experimental groups and bone density were showed higher than control. There were a little difference between experimental group A and B. In conclusion, absorbable gelatin sponge and with PRP were considered as having preservation effects of extraction socket and stimulation of bone formation process after extraction.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.33 no.3
• /
• pp.264-269
• /
• 2011

An extraction socket was preserved and reconstructed using an autogenous tooth bone graft powder and block in two patients. The grafted site was healed 3 to 3.5 months after surgery. Implant treatment was successfully completed.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.23 no.1
• /
• pp.15-20
• /
• 2001

For the earlier diagnosis and treatment of delayed wound healing in extraction socket, we investigated the clinical, radiographic and histopathologic features of 106 patients with delayed wound healing diagnosed by biopsy. The patients were enrolled at the Department of Oral Pathology, Chosun University Dental Hospital. Among 106 delayed wound healing diagnosed by biopsy, cysts showed most significant 25 cases (23%), osteomyelitis showed 13 cases (12%), chronic maxillary sinusitis and squamous cell carcinoma showed 12 (11%) and 11 (10%) cases, respectively. We have analyzed these lesions through relevant literatures.

• Transactions of Materials Processing
• /
• v.16 no.6
• /
• pp.479-487
• /
• 2007

Die life is generally estimated taking failure life and wear amount into consideration. In this study, the forging die life was investigated considering both of these two factors. The fatigue life prediction for the die was performed using the stress-life method, i.e. Goodman's and Gerber's equations. The Archard's wear model was used in the wear life simulation. These die life prediction techniques were applied to the die used in the forging process of the socket ball joint of a transportation system. A rigid-plastic finite element analysis for the die forging process of the socket ball was carried out and also the elastic stress analysis for the die set was performed in order to get basic data for the die fatigue life prediction. The wear volume of the die was measured using a 3-dimensional measurement apparatus. The simulation results were relatively in good agreement with the experimental measurements.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2008.03a
• /
• pp.1250-1253
• /
• 2008

As a reinforcement technique, the application of removable soil nailing has been extended to solve the public grievance of typical soil nailing such as the geotechnical environmental problem and invasion of adjacent land. In the case of removable soil nailing, pullout capacity of the nail depends on the adhesive strength of a fixed socket. Because the existing fixed socket is made from a plastic product, the strength of a socket is less than a steel bar and then the yield failure by abrasion and deformation is occurred on the steel bar-socket contact surface. In this study, therefore, experimental analysis from laboratory test of a removable soil nail equipped with steel socket, improving the adhesive strength of steel bar-socket connection is performed to estimate the increase effect of pullout capacity of a soil nail.

• Archives of Plastic Surgery
• /
• v.48 no.1
• /
• pp.80-83
• /
• 2021

Eye socket contracture is a well-known late complication of enucleation surgery, and the additional insult of radiotherapy at an early age causes even further fibrosis and scarring of the socket. Management of the contracted socket is challenging, and several methods have been proposed. We report a case of eye socket contracture after enucleation and radiotherapy in which multiple reconstructive procedures failed. The recurrent contracture caused difficulty in housing and retaining the eye prosthesis. We reconstructed the lower eyelid with a facial artery myomucosal flap and nasolabial flap, and the upper eyelid with a Fricke flap following reconstruction of the orbital rims (supraorbital and infraorbital rims with a calvarial bone graft, and further augmentation of the infraorbital rim with a rib bone graft). Cosmesis post-reconstruction was acceptable and the prosthesis was retained very well.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.11 s.254
• /
• pp.1433-1438
• /
• 2006

A systematic approach to socket shape design of a concave piston assembly for a high pressure hydraulic pump of an excavator is presented in this paper. A design model is given and a methodology of socket shape design is proposed. An axisymmetric rigid-plastic finite element method is employed for predicting the approximate socket shape formed by a rotary forming process as well as for simulating the test process for separating the shoe from the piston assembly designed. It is verified that the predictions are in good agreement with the experiments. The approach is successfully applied to developing an optimal concave piston assembly.