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

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1360-1364
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• 2009

Necessity of removable soil nailing has been arisen in the soil nailing system because of problem such as civil petition for geotechnical environment and invasion of the ground boundary line and payments for use besides geotechnical engineering. Removable soil nailing system is improved soil nailing system that fixed socket arranged in boring hole for increasement of skin friction. In this study, field pull-out tests are carried out more 4 times considering installed distance of fixed socket and analyze skin friction behavior characteristics in fixed socket through analysis of measurements of strain gauge attached to fixed socket. Also, to evaluate application for wedge type removable soil nailing system analyzing displacement aspects through field pull-out tests by trial construction.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.137-144
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• 1999

Recently a removable soil nail is demanded due to problems beyond of economical and engineering purpose. In this study removable soil nails are developed and field pull-out tests are carried out 16 times in order to analysis pull-out characteristics of the removable soil nail. For the spacing and the installed position of fixed socket, the length of the soil nail, and W/C ratio of cement grout in the removable soil nail, pull-out characteristics of pull-out tests are analyzed. From the pull-out characteristics of removable soil nails, it is found that the spacing of fixed socket and W/C ratio of cement grout are important design parameters.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.1330-1333
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• 2009

The soil nailing method had used in variable construction field because of construction convenience and reinforcement effect. Especially, the removal soil nailing method is useful support system in vertical excavation. In this study, to develop the wedge type removable soil nailing method for improvement of the removal soil nailing method. Because of the reinforcement materials is most important in soil nailing method, to evaluate the mechanical characteristics during laboratory strength test in this study. To conduct bond strength test of deformed bar combined with a wedged screw inside plastic fixed socket for evaluate the strength characteristics of wedge type removable soil nailing method and evaluate the strength characteristics of fixed socket based on laboratory tests.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.40-45
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• 2005

Techniques used for throcket motors are mainly classified as fixed nozzles with mechanical exhaust jet interferences on the expansion region (such as jet tabs and jet vanes) and movable nozzles(such as ball&socket md flexible seal). Using the numerical analysis and the cold-flow test, this paper evaluates the performance of supersonic nozzle for asymmetric entrance shape at tilted position of ball&socket nozzle. Numerical results show that the asymmetric effects in the flow fields are gradually diminished up to the nozzle throat and are not noticeable downstream of the nozzle throat. Although the calculated thrust and the lateral force are less than those of cold-flow test, two results show a flirty good agreement.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.149-156
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• 1998

In suspension bridges, the axial farces in the wires are transferred by side pressure on the semicircular face, and further from the strand shoe through rods to a base plate fixed to the massive concrete part of the anchor block. For prefabricated strands the most common way of anchoring is by socketing the ends of the strands. In this study, strand shoe and hanger socket are analyzed far various load conditions using Finite Element Method. The finite element models are built using MSC/PATRAN and analysis is carried out using MSC/NASTRAN. Results are again completely processed using MSC/PATRAN. From the results of the analysis, trends of deformation and stress distribution are reviewed and important factors to consider in the design of strand shoe and hanger socket are discussed.

• Proceedings of the KAIS Fall Conference
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• 2012.05b
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• pp.607-608
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• 2012

본 논문에서는 콘센트의 품질이나 기능이 비약적으로 발전하였으나, 기존 노출형 콘센트에 플러그를 연결하는 경우에 쉽게 빠지는 경우가 발생하거나, 콘센트와 플러그가 외부에 바로 노출되어 있어 먼지나 수분에 취약한 문제가 있어 그 해결책을 해결하고자 하였다. 콘센트와 플러그 사이에 콘센트 고정 장치를 결합하는 방법을 제시하고, 매입형 콘센트의 경우에도 고정 장치를 쉽게 결합하여 빠지는 현상을 방지하고, 먼지나 수분에 의한 감전사고 예방 효과를 누릴 수 있는 제품을 개발하고자 하였다.

• The Journal of Advanced Prosthodontics
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• v.4 no.3
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• pp.174-178
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• 2012

When performing a tooth extraction, imminent collapse of the tissue by resorption and remodeling of the socket is a natural occurrence. The procedure for the preservation of the alveolar ridge has been widely described in the dental literatures and aims to maintain hard and soft tissues in the extraction site for optimal rehabilitation either with conventional fixed or removable prosthetics or implant-supported prosthesis.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.481-488
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• 1999

Recently a removable soil nail is demanded due to problems beyond of economical and engineering purpose. In this study controlled displacement and controlled force field pull-out tests are carried out 7 times in order to evaluate short-term and long-term pull-out characteristics of the removable soil nail. For evaluating application of removable soil nailing system, bending tests of removable soil nails and tensile tests of fixed sockets are carried out. In the removable soil nailing system, the predicted horizontal displacements from FLAC-2D are also compared with the field measurements occurred in stepwise excavation. And approach for the stability analysis of removable soil nailing system after removed is proposed.

• Journal of Periodontal and Implant Science
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• v.49 no.3
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• pp.171-184
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• 2019

Purpose: To evaluate the effects of intra-alveolar socket grafting, subepithelial connective tissue grafts, and individualized abutments on peri-implant hard and soft tissue outcomes following immediate implant placement. Methods: This randomized experimental study employed 5 mongrel dogs, with 4 sites per dog (total of 20 sites). The mesial roots of P3 and P4 were extracted in each hemimandible and immediate dental implants were placed. Each site was randomly assigned to 1 of 4 different treatment groups: standardized healing abutment (control group), alloplastic bone substitute material (BSS) + standardized healing abutment (SA group), BSS + individualized healing abutment (IA group), and BSS + individualized healing abutment + a subepithelial connective tissue graft (IAG group). Clinical, histological, and profilometric analyses were performed. The intergroup differences were calculated using the Bonferroni test, setting statistical significance at P<0.05. Results: Clinically, the control and SA groups demonstrated a coronal shift in the buccal height of the mucosa ($0.88{\pm}0.48mm$ and $0.37{\pm}1.1mm$, respectively). The IA and IAG groups exhibited an apical shift of the mucosa ($-0.7{\pm}1.15mm$ and $-1.1{\pm}0.96mm$, respectively). Histologically, the SA and control groups demonstrated marginal mucosa heights of $4.1{\pm}0.28mm$ and $4.0{\pm}0.53mm$ relative to the implant shoulder, respectively. The IA and IAG groups, in contrast, only showed a height of 2.6mm. In addition, the height of the mucosa in relation to the most coronal buccal bone crest or bone substitute particles was not significantly different among the groups. Volumetrically, the IA group ($-0.73{\pm}0.46mm$) lost less volume on the buccal side than the control ($-0.93{\pm}0.44mm$), SA ($-0.97{\pm}0.73mm$), and IAG ($-0.88{\pm}0.45mm$) groups. Conclusions: The control group demonstrated the most favorable change of height of the margo mucosae and the largest dimensions of the peri-implant soft tissues. However, the addition of a bone substitute material and an individualized healing abutment resulted in slightly better preservation of the peri-implant soft tissue contour.