• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.3
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• pp.225-231
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• 2008

This study evaluated whether there is a difference between a conventional titanium distraction device and a TiN-coated device in terms of implant osseointegration after horizontal distraction osteogenesis in narrow alveolar bone. Four adult mongrel dogs, each weighing $9{\sim}10kg$, were used in this study. The lower premolars were extracted and horizontal distraction was performed with conventional titanium distraction devices (group 1) or TiN-coated devices (group 2). After an 8-week consolidation period, the implants were installed, and the dogs were sacrificed after another 8 weeks. The osseointegration around the implants was evaluated histomorphologically. There was one failure in experimental group 1 because of fracture of the device. Direct bone contact was achieved and there were no significant differences between the control group and experimental groups 1 and 2 in terms of osseointegration around the implants at 8 weeks. In summary, intraoral distraction osteogenesis is a good option for augmenting severely atrophied alveolar ridges, and the TiN-coated device may be useful because of its advantages, which include surface hardness, corrosion resistance, and reduced bacteria.

• Geotechnical Engineering
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• v.13 no.1
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• pp.19-34
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• 1997

Applications of geostatistical method to cone penetrometer data have been performed at the overconsolidated clay site. Randomlylocated 28 electronic CPT soundings (Location A) and consistently-located 38 CPT soundings(Location B) are investigated geostatistically. Variograms for Locations A and B have been developed for q, from the CPT data by using "kriging" principles, which establish the horizontal and vertical correlation distrances at this site. These vertical and horizontal correlation distances can be used to optimal sampling design, where, if one needs to compare two test results, sampling must be made within these vertical and horizontal correlation distances. Analysis of the variograms indicated that the geological formation between two locations are not very different in both vertical direction and horizontal direction.direction.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.207-212
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• 2002

The actual buckling of the railroad track structure is suspected to be a complex interaction between the vertical, lateral and torsional modes. To make the analysis tractable, however, most studies restrict themselves to either the vertical or the horizontal plane. Based on a comprehensive and realistic three-dimensional track model developed in the previous study, three dimensional buckling analysis of CWR track subjected to temperature load was performed. Using the study on buckling temperature and mode, sensitivity of track components such as tie spacing, ballast resistance, stiffness of pad-fastening system and rail size were investigated.

• Journal of Microbiology
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• v.45 no.6
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• pp.590-592
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• 2007

We report the isolation of Salmonella enterica serotype Typhimurium phage type DT104 (CCARM 8104) from swine in Korea. The CCARM 8104 isolate was resistant to nalidixic acid and showed reduced susceptibility to quinolones. The CCARM 8104 isolate had a missense mutation, Asp87Asn, in the quinolone resistance-determining region in gyrA and produced PSE-1. The CCARM 8104 isolate carried two different class 1 integrons, and the PSE-1 ${\beta}$-lactamase gene was inserted into a 1,200 bp class 1 integron. The presence of DT104 with pse-1 in an integron located in a plasmid and reduced susceptibility to quinolone in swine pose a significant threat of possible horizontal spread between swine and humans.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.407-414
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• 2000

The friction pendulum type seismic isolation system (FPS) has been developed to provide a simple and effective way to achieve earthquake resistance for buildings . The major advantages are: the isolation frequency can be easily achieved by designing a curvature of the surface and does not depend on the supported weight of a structure. The function of carrying vertical load is separated to the function of providing horizontal stiffness. Next the friction provides sufficient energy dissipation to protect the structure from earthquake response and resistance to the weak external disturbances such as wind load and ground vibrations due to traffic. In this paper, the friction coefficients are evaluated from number of experiments on the FPS test specimens. The relations between friction coefficient and the test waveform, velocity, and pressure are reviewed and further works are discussed.

• Steel and Composite Structures
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• v.29 no.3
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• pp.309-318
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• 2018

Steel girders are the structural members often used for passing long spans. Mostly being subjected to patch loading, or concentrated loading, steel girders are likely to face sudden deformation or damage e.g., web breathing. Horizontal or vertical stiffeners are employed to overcome this phenomenon. This study aims at assessing the feasibility of a machine learning method, namely the support vector machines (SVM) in predicting the patch loading resistance of longitudinally stiffened webs. A database consisting of 162 test data is utilized to develop SVM models and the model with best performance is selected for further inspection. Existing formulations proposed by other researchers are also investigated for comparison. BS5400 and other existing models (model I, model II and model III) appear to yield underestimated predictions with a large scatter; i.e., mean experimental-to-predicted ratios of 1.517, 1.092, 1.155 and 1.256, respectively; whereas the selected SVM model has high prediction accuracy with significantly less scatter. Robust nature and accurate predictions of SVM confirms its feasibility of potential use in solving complex engineering problems.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.251-254
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• 2009

Thermal performance of a thermosiphon for medium-temperature solar thermal application was investigated. The working fluid was Dowtherm A and the container was made of STS 316L. The thermosiphon had a outer diameter of 12.7 mm and a total length of 2 m, where the evaporator and the condenser had the same length of 0.3 m and the adiabatic section was 1.4 m. Both the evaporator and the condenser were aligned horizontal with an elevation difference of 0.18 m to utilize the gravitational force for the working-fluid return. The optimum fill charge ratio of the working fluid was investigated to obtain the maximum heat transport with the lowest thermal resistance. The maximun input thermal load was 500 W and thermal resistance was $0.60^{\circ}C/W$.

• Journal of the Korean Society for Railway
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• v.5 no.1
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• pp.1-9
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• 2002

Where the track is continuously welded over the bridge, the longitudinal forces will be distributed interactively between the track and the sub-structure by the rail-bridge interaction mechanism. The ratio between the longitudinal forces transmitted in each elements depends on the magnitude of the ballast resistance and the stiffness of the sub-structures. In this paper, the main factors affect on the longitudinal rail force are discussed and the parametric study for the behavior of CWR(Continuous Welded Rail) track was executed. It is concluded that the horizontal ballast resistance and the stiffness of the bridge sub-structure are the significant parameters affecting the stability of the continuous welded rail track.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1114-1119
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• 2010

Pile foundations have been used for upholding superstructure's loads. The researches on pile foundations subjected to compressive forces or horizontal loads have been actively carried out. However, recently, pile foundations, which are subjected to pull-out forces, are getting increased. The study on the pull-out resistance of piles becomes to be important. In addition, it is expected that belled piles will be used more and more, since the belled piles are effective to resist the pull-out forces. But there is still a lack of research on pull-out resistance of belled piles. Therefore, in order to investigate the resisting effect against pull-out of belled piles which is embedded in cohesionless soil. a series of pull-out test is performed on belled piles in field. Especially, the relation between load and displacement is analyzed through the pull-out test.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.191-192
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• 2009

Multi-purpose spatial structure is easy to modify the inner part of the building that is required vertical and horizontal enlargement and service change. Thus, the results indicate the effective lateral resistance system of multi-purpose spatial structure using mega elements.