• Proceedings of the KSR Conference
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• 2003.05a
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• pp.46-52
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• 2003

In this study, the full scale testing method of the geogrid-reiuorced soil Segmental Retaining Walll(SRW) under the simulated train loading were proposed in order to evaluate the applicability of reinforced soil SRW in railway embankment. The train loading was simulated by the design static wheel load and the impact coefficient due to the train passing velocity. This test was focused on the static performance of reinforced soil SRW in terms of the following measuring systems ; the horizontal earth pressure displacement acting on the facing block and the tensile strain along the geogrid. The data gathered from this full scale testing was compared with numerical analysis results by FLAC.

• The Journal of Advanced Prosthodontics
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• v.2 no.1
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• pp.1-3
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• 2010

BACKGROUND. Even though excellent impression materials are now available for making accurate replication for hard and soft tissue, the numerous dentists have faced lots of obstacles in making simultaneous impressions of multiple abutments. CASE DESCRIPTION. This article describes a modified method of tray fabrication using auto-polymerizing acrylic resin and impression technique for multiple prepared teeth in cases with limitations and difficulties in taking dental impressions. CLINICAL IMPLICATION. This segmental tray technique has several advantages, including higher impression quality, fewer impressions, and being more comfortable for the patient and less stressful for the clinician.

• Journal of Digital Convergence
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• v.20 no.4
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• pp.159-168
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• 2022

This study was conducted to classify segmental group based on the factors of foodservice motivation and then conducted a survey for one month from July 15 to August 14, 2021 to analyze the influence of demographic characteristics, usage behavior, and motivation on eating out choice behavior. A total of 310 copies were used for empirical analysis. The result is as follows. First, males showed higher task type than females, and females showed higher number of change type, gastronomic type, and fit type. Second, in demographic characteristics, all groups showed strong motivation for foodservice in married people aged 31-40 and 41-50. Third, in the restaurant selecting behavior difference between the segmental groups according to the motivation for foodservice the most preferred menu was korean food for fit type, gourmet type, duty type and western food was the highest in the change type. Fourth, in the ordering method of difference in restaurant selecting behavior among segmental groups, all four groups showed higher order type than unlimited type or buffets type. The limitations of this study are limited to the food field and analysis should be done, but the results of the study on specific food items have not been obtained. Therefore, it is hoped that the future research will be conducted by designating specific food fields.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.186-189
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• 2003

Precast Segmental method was developed in germany 1950s. This method has been adoptted in long span girder mainly owing to easy construction effect. But, so far, The limit exists that this method is constructed in a portion of span and hard conveyance and foundation. This study was performed to analysis behavior difference of two rectanglar section girder, spliced girder that was jointed 5-sliced 0.8m segment and monolithic girder that was produced in one body 4m span

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1990.10a
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• pp.101-104
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• 1990

The program which could determine cross-sectional dimensions of the box girder bridge at tile stage of preliminary design was developed using the optimal technique in this study. It could minimize the cost and time required in the design of box girder bridges and the construction with the prestressed precast segmental method. Objective cost function consisted of four independent variables such as widths and depth of the cross-section. The Nelder-Mead method was used to solve the nonconstrained nonlinear problem like this.

• Journal of Korean Neurosurgical Society
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• v.38 no.4
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• pp.255-258
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• 2005

Objective : Lumbar lordotic curve on L4 to S1 level is important in maintaining spinal sagittal alignment. Although there has been no definite report in lordotic value, loss of lumbar lordotic curve may lead to pathologic change especially in degenerative lumbar disease. This study examines the changes of lumbar lordotic curve after posterior lumbar interbody fusion with wedge shape cage. Methods : We studied 45patients who had undergone posterior lumbar interbody fusion with wedge shape cage and screw fixation due to degenerative lumbar disease. Preoperative and postoperative lateral radiographs were taken and one independent observer measured the change of lordotic curve and height of intervertebral space where cages were placed. Segmental lordotic curve angle was measured by Cobb method. Height of intervertebral space was measured by averaging the sum of anterior, posterior, and midpoint interbody distance. Clinical outcome was assessed on Prolo scale at 1month of postoperative period. Results : Nineteen paired wedge shape cages were placed on L4-5 level and 6 paired same cages were inserted on L5-S1 level. Among them, 18patients showed increased segmental lordotic curve angle. Mean increased segmental lordotic curve angle after placing the wedge shape cages was $1.96^{\circ}$. Mean increased disc height was 3.21mm. No cases showed retropulsion of cage. The clinical success rate on Prolo's scale was 92.0%. Conclusion : Posterior lumbar interbody fusion with wedge shape cage provides increased lordotic curve, increased height of intervertebral space, and satisfactory clinical outcome in a short-term period.

• Archives of Reconstructive Microsurgery
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• v.16 no.2
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• pp.100-107
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• 2007

Treatment of giant cell tumor of distal radius can be treated in several ways according to the aggressiveness of the tumor. But the management of giant cell tumor involving juxta-articular portion has always been a difficult problem. In some giant cell tumors with bony destruction, a wide segmental resection may be needed for preventing to recur. But a main problem is preserving of bony continuity in bony defect as well as preservation of joint function. We have attempted to overcome these problems by using a microvascular technique to transfer the fibula with peroneal vascular pedicle or anterior tibial vessel as living bone graft. From April 1984 to July 2005, we performed the reconstruction of wide bone defect after segmental resection of giant cell tumor in 14 cases, using Vascularized Fibular Graft, which occur at the distal radius. VFG with peroneal vascular pedicle was in 8 cases and anterior tibial vessel was 6 cases. Recipient artery was radial artery in all cases. Method of connection was end to end anastomosis in 11 cases, and end to side in 3 cases. An average follow-up was 6 years 6 months, average bone defect after wide segmental resection of lesion was 6.8 cm. All cases revealed good bony union in average 6.5 months, and we got the wide range of motion of wrist joint without recurrence and serious complications. Grafted bone was all alive. In functional analysis, there was good in 7 cases, fair in 4 cases and bad in 1 case. Pain was decreased in all cases but there was nearly normal joint in only 4 cases. Vascularized fibular graft around wrist joint provided good functional restoration without local recurrence.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.305-308
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• 2008

The purpose of this study is to propose the confinement effectiveness of precast segmental concrete that binding by lateral confining steel in the method of precast segmental concrete pridge piers construction. Generally, the confinement effect of concrete that binding by lateral confining steel is defined by the confinement effectiveness coefficient and the confinement effectiveness coefficient is defined as the ratio of area of effectively confined concrete core to area of confined concrete core. The area of effectively confined concrete core is defined by Arching action occurred on a space of lateral confinement steel and The area of confined concrete core is defined by the ratio of area of longitudinal reinforcement to area of core of section. But in case of precast segmental concrete, concrete cover that exist on top and bottom of concrete segment should be considered.

• Journal of the Korean Geotechnical Society
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• v.24 no.9
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• pp.23-32
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• 2008

This paper presents the global stability of geosynthetic reinforced segmental retaining walls in tiered configuration. Four design cases of walls with different geometries and offset distances were analyzed based on the FHWA and NCMA design guidelines and the discrepancies between the different guidelines were identified. A series of global slope stability analyses were conducted using the limit-equilibrium analysis and the continuum mechanics based shear strength reduction method with the aim of identifying failure patterns and the associated factors of safety. The results indicated among other things that the FHWA design approach yields conservative results both in the external and internal stability calculations, i.e., lower factors of safety, than the NCMA design approach. It was also found that required reinforcement lengths are usually governed by the global slope stability requirement rather than the external stability calculations. Also shown is that the required reinforcement lengths for the upper tiers are much longer than those based on the current design guidelines.

• Structural Engineering and Mechanics
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• v.20 no.6
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• pp.673-693
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• 2005

A general step-by-step simulation for the time-dependent analysis of segmentally-erected prestressed concrete box-girder bridges is presented. A three dimensional finite-element model for the balanced-cantilever construction of segmental bridges, including effects of the load history, material nonlinearity, creep, shrinkage, and aging of concrete and the relaxation of prestressing steel was developed using ABAQUS software. The models included three-dimensional shell elements to model the box-girder walls and Rebar elements representing the prestressing tendons. The step-by-step procedure allows simulating the construction stages, effects of time-dependent deformations of materials and changes in the structural system of the bridges. The structural responses during construction and throughout the service life were traced. A comparison of the developed computer simulation with available experimental results was conducted and good agreement was found. Deflection of the bridge deck, changes in stresses and strains and the redistribution of internal forces were calculated for different examples of bridges, built by the balanced-cantilever method, over thirty-year duration. Significant time-dependent effects on the bridge deflections and redistribution of internal forces and stresses were observed. The ultimate load carrying capacities of the bridges and the behavior before collapse were also determined. It was observed that the ultimate load carrying capacity of such bridges decreases with time as a result of time-dependent effects.