• Animal Systematics, Evolution and Diversity
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• v.20 no.1
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• pp.79-85
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• 2004

Pholcus gosuensis sp. novo is described from the entrance zone of Gosu cave, Chungchengbuk-do, Korea. The species is characterized by male palpal organs with three expanded apophyses and developed callosity on procursus, two frontal apophyses of chelicerae and degrading appendix, and sclerotized arches on uterus externus. The species is related to P. crassus Paik 1978 and P. acutulus Paik, 1978 in having identical uncus and embolus but differentiated from those species by the combined characters of large apophyses and heavily sclerotized callosity on procursus, and structure of arches on uterus externus.

• The Journal of Advanced Prosthodontics
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• v.13 no.4
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• pp.205-215
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• 2021

PURPOSE. The purpose of this study was to compare the accuracy of three intraoral scanner (IOS) systems with three different dental arch widths. MATERIALS AND METHODS. Three dental models with different intermolar widths (small, medium, and large) were attached to metal bars of different lengths (30, 40, and 50 mm). The bars were measured with a coordinate measuring machine and used as references. Three IOSs were compared: TRIOS 3 (TRI), True Definition (TD), and Dental Wings (DW). The relative length and angular deviation of both ends of the metal bars from the scan data set (n = 15) were calculated and analyzed. RESULTS. Comparing among scanners in terms of trueness, the relative length deviation of DW in the small (1.28%) and medium (1.08%) arches were significantly higher than TRI (0.46% and 0.48%) and TD (0.33% and 0.18%). The angular deviation of DW in the small (1.75°) and medium (1.83°) arches were also significantly greater than TRI (0.63° and 0.40°) and TD (0.55° and 0.89°). Comparing within scanner, the large arch of DW showed better accuracy than other arch sizes (P < .05). On the other hand, the larger arch of TD presented a greater tendency of angular deviation in terms of trueness. No significant differences were found in terms of trueness between the arch widths of TRI group. CONCLUSION. The different widths of the dental arches can affect the accuracy of some intraoral scanners in full arch scan.

• The Journal of the Korean dental association
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• v.14 no.10
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• pp.805-806
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• 1976

• Journal of Korean Association for Spatial Structures
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• v.8 no.5
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• pp.9-13
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• 2008

• The Journal of the Korean dental association
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• v.11 no.7
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• pp.491-497
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• 1973

• Structural Engineering and Mechanics
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• v.67 no.5
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• pp.481-492
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• 2018

The current experimental study is the reinforcement of the simple curvature vault masonry structures. In this study, we discuss complex structure include vault and rib cover with two radii and actual dimensions under a vertical load. The unreinforced structure data were compared with analysis data. The analysis data are in good agreement with experimental data. In the first experiment, a structure without reinforcement is tested and according to the test results, the second structure was reinforced using the carbon polymer fibers and the same test is done to see the effects of reinforcement. Based on the test results of the first structure, the first cracks are created in the vault. Moreover, the reinforcement with carbon fibers will increase the loading capacity of the structure around 35%.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.340-343
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• 2007

The differential equations governing free, in-plane vibrations of non-circular arches with the translational (radial and tangential directions) and rotational springs at the ends, including the effects of rotatory inertia, shear deformation and axial deformation, are solved numerically using the corresponding boundary conditions. The lowest four natural frequencies for the parabolic geometry are calculated over a range of non-dimensional system parameters: the arch rise to span length ratio, the slenderness ratio, and the translational and rotational spring parameters.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1181-1184
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• 2007

The differential equations governing free, in-plane vibrations of linearly elastic circular arches with rotationally flexible supports, including the effects of rotatory inertia, shear deformation and axial deformation, are solved numerically using the corresponding boundary conditions. The lowest four natural frequencies and the corresponding mode shapes are obtained over a range of non-dimensional system parameters: the subtended angle, the slenderness ratio, and the rotational spring stiffness.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1169-1172
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• 2007

This paper deals with the free vibrations of cantilever arches with constant volume. Its cross-sectional shape is the regular polygon whose depth is varied with the linear functional fashion. The non-dimensional differential equations governing the free vibration of such arch are derived and solved numerically for calculating the natural frequencies. As the numerical results, the effects of arch parameters such as side number of cross section, section ratio and aspect ratio on the natural frequencies are reported in figures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.169-176
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• 1999

An improved formulation for spatial stability md free vibration of thin-walled curved beams with variable curvature and non-symmetric cross sections are presented based on the displacement field considering the second order terms of finite semitangential rotations. By introducing Vlasov's assumptions, the total potential energy is derived from the principle of linearized virtual work for a continuum. In this formulation, all displacement parameters and the warping function are defined at the centroid axis so that the coupled terms of bending and torsion are added to the elastic strain energy. Also, the potential energy due to initial stress resultants is consistently derived corresponding to the semitangential rotation and moment. The cubic Hermitian polynomials are utilized as shape functions for development of the curved thin-walled beam element having eight degrees of freedom. In order to illustrate the accuracy and practical usefulness of this study, . numerical solutions for free vibration of arches are presented and compared with resells of other researchers and solutions analyzed by the ABAQUS's shell element.