• Proceedings of the KSME Conference
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• 2004.11a
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• pp.480-485
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• 2004

The applications of composite materials have increased over the past few decades in a variety of structures that require high ratio of stiffness and strength to weight ratios. Recently the thick open section composite beams are used extensively as load carrying members and stiffeners of structural elements. However, most of studies on thick composite beams are limited only to closed section beams. In this study, an open cross-section thick-walled composite beam model which includes coupled stiffness, transverse shear, and warping effects is suggested and the deflections associated with the thick-walled composite beams and thin-walled composite beams are obtained and compared with the finite element analysis results.

• Journal of Veterinary Science
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• v.24 no.2
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• pp.28.1-28.7
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• 2023

A three-year-old female spayed Lurcher was referred for the treatment of a highly comminuted distal tibial articular fracture. Resection of the area of comminution with a transverse osteotomy of the tibial diaphysis and talar ridges was performed, followed by modified pantarsal arthrodesis and a calcaneotibial screw. The treatment resulted in 7 cm of tibial shortening, equating to a 28% reduction in the total tibial length. Radiographic union of the arthrodesis was successful. Fair use of the pelvic limb was documented long-term. Combined acute limb shortening and modified pantarsal arthrodesis resulted in an acceptable outcome and could be considered in cases of highly comminuted distal tibial fractures.

• Steel and Composite Structures
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• v.23 no.1
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• pp.17-29
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• 2017

The seismic performance of steel beam to concrete-encased composite column with unsymmetrical steel section joints is investigated and reported within this paper. Experimental and analytical evaluation were conducted on a total of 8 specimens with T-shaped and L-shaped steel section under lateral cyclic loading and axial compression. The test parameters included concrete strength, stirrup ratio and axial compression ratio. The response of the specimens was presented in terms of their hysterisis loop behavior, stress distribution, joint shear strength, and performance degradation. The experiment indicated good structural behavior and good seismic performance. In addition, a three-dimensional nonlinear finite-element analysis simulating was conducted to simulate their seismic behaviors. The finite-element analysis incorporated both bond-slip relationship and crack interface interaction between steel and concrete. The results were also compared with the test data, and the analytical prediction of joint shear strength was satisfactory for both joints with T-shaped and L-shaped steel section columns. The steel beam to concrete-encased composite column with unsymmetrical steel section joints can develop stable hysteretic response and large energy absorption capacity by providing enough stirrups and decreased spacing of transverse ties in column.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.525-530
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• 2007

Although just developed in recent years, curved box girder has widely used in modern highway system due to their load resistance capacity as well as aesthetic considerations. According to recent literature reviews on curved box girder designs, distortional load was not considered as much as it deserves to be. In practice, the effect of distributional force is very small in straight bridge systems but yet unknown how it is in curved bridge systems. For the reason, this paper will show up an extensive parametric study on distortional behavior of curved box girder with trapezoidal section. Based on Dabrowski formulas, using finite element method, various bridges were investigated. In this study, following parameters will be included: span length, curvature radius, section height, section width, and internal section angle (web slope). From the obtained results, some initial geometric parameters are proposed for curved box girder bridges.

• Journal of Plant Biology
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• v.13 no.2
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• pp.1-10
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• 1970

This experiment surveys ecological and morphological phase on Prasiola sp. in the mountain torrent of Chodang-ri, Keunduck-myon, Samchuck-gun, Kangwon-do, Korea from November 1968 through January 1970 and the results obtained were summarized as follows. 1. The temperature of the surface water was 12.4$\pm$2.3$^{\circ}C$, and pH was 7.25$\pm$0.2. 2. The external forms of thallus are very variable, but its basic form likely lanceolated and ovated. 3. The length of thallus is 0.6cm-8.8cm (3.6$\pm$1.72cm), and the width, 0.2cm-5.5cm(1.7$\pm$0.92cm). (The inside of the parentheses the average for 500 individuals). 4. It is observed that thallus at the time of formation of a monospore is a monostratum cell whose thickness is 21$\pm$3.2$\mu$. 5. Thickness of thallus at the transveres section at the time of heteroplanogametes formation is 29.9$\pm$2.2$\mu$, and that of the female gametes cell is 6.3$\pm$1.7$\times$6.3$\pm$0.8$\mu$, and that of the male gametes cell is 2.8$\pm$0.6$\times$28.1$\pm$1.1$\mu$. 6. As for growth, it begins with apical growth, followed by marginal growth. It seems to grow, through cell division when microsopical papillae are produced in growth line cell of marginal rigion thus by fusioning microscopical papillae. 7. The two kinds of thallus, one produced from a monospore and other from a planozygotes, are both haplonts and observed as n-3. 8. It seems that a thallus sprouts in April and increases its number through a asexual reproduction by a monospore and begins a sexual reproduction in November by forming gametes. 9. Female gametes are produced 16 from one thallus cell, whose structure shows 8 cells in the surface view and 4 layers in transverse section. Male gametes are produced 128 from one thallus cell, 16 cells surface, 8 layers in transverse section.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.1-9
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• 2015

Transverse steel bars are used in the plastic hinge zone of columns to insure adequate confinement, prevention of longitudinal bar buckling and ductile behavior. Fabrication and placement of rectangular hoops and cross-ties in columns are difficult to construct. Details of reinforcement for rectangular section require a lot of rectangular hoops and cross-ties. In this paper, to solve these problems, the new lateral confinement method using oblong hoop is proposed for the transverse confinement of the flared column. It can be the alternative for oblong cross-section and flared column with improved workability and cost-efficiency. The final objectives of this study are to suggest appropriate oblong hoop details and to provide quantitative reference data and tendency for seismic performance or damage assessment based on the drift levels such as residual deformation, elastic strain energy. This paper describes factors of seismic performance such as ultimate displacement/drift ratio, displacement ductility, response modification factor, equivalent viscous damping ratio and effective stiffness.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.201-204
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• 2008

The Sectional Design Model(AASHTO LRFD) is appropriate for the design of typical bridge girders, slabs, and other regions of components where the assumptions of traditional engineering beam theory are valid. The shear resistance of a concrete member may be separated into a component, $V_c$, that relies on tensile stresses in the concrete, $V_s$, that relies on tensile stresses in the transverse reinforcement. The expressions for $V_c$ and $V_s$ apply to both prestressed and nonprestressed section, with the terms ${\beta}$ and ${\theta}$ depending on the applied loading(M, V, N, and T) and the properties of the section. With ${\beta}$ taken as 2.0 and ${\theta}$ as 45$^{\circ}$, the expressions for shear strength become essentially identical to those traditionally used for evaluating shear resistance. Recent large-scale experiments, however, have demonstrated that these traditional expression can be seriously unconservative for large members not containing transverse reinforcement. And This paper can present only a brief introduction to shear design of AASHTO LRFD and is to review of the technical difficulty.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.18-25
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• 2012

This paper estimates the ductility of reinforced concrete columns according to configurations of transverse reinforcement. A total of 8 reinforced concrete columns were cast and tested in flexure. The test variables in this study were the configurations, yield strength, and amount of transverse reinforcement. The specimens had a cross-section of $250{\times}250mm$ and had a shear span-to-depth ratio of 4.1 to induce flexural failure. In the test, cyclic lateral load was applied to the specimens with a constant axial load. The experimental result indicated that the specimens with proposed configurations of transverse reinforcement showed higher ductility and energy dissipation capacity than the specimens with rectangular tie.

• Journal of the Korean Society of Safety
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• v.19 no.4 s.68
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• pp.25-30
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• 2004

Unidirectional fiber-metal matrix composites have superior mechanical properties along the longitudinal direction. However, the applicability of continuous fiber reinforced MMCs is somewhat limited due to their relatively poor transverse properties. Therefore, the transverse properties of MMCs are significantly influenced by the properties of the fiber/matrix interface. In this study, the interfacial stress states of transversely loaded unidirectional fiber reinforced metal matrix composites investigated by using elastic-plastic finite element analysis. Different fiber volume fractions $(5-60\%)$ were studied numerically. The interface was treated as thin layer (with different properties) with a finite thickness between the fiber and the matrix. The fiber is modeled as transversely isotropic linear-elastic, and the matrix as isotropic elastic-plastic material. The analyses were based on a two-dimensional generalized plane strain model of a cross-section of an unidirectional composite by the ANSYS finite element analysis code.

• Structural Engineering and Mechanics
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• v.27 no.6
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• pp.741-771
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• 2007

Tests were conducted on two partially pre-stressed concrete solid beams subjected to combined loading of bending, shear and torsion. The beams were designed using the Direct Design Method which is based on the Lower Bound Theorem of the Theory of Plasticity. Both beams were of $300{\times}300mm$ cross-section and 3.8 m length. The two main variables studied were the ratio of the maximum shear stress due to the twisting moment, to the shear stress arising from the shear force, which was varied between 0.69 and 3.04, and the ratio of the maximum twisting moment to the maximum bending moment which was varied between 0.26 and 1.19. The required reinforcement from the Direct Design Method was compared with requirements from the ACI and the BSI codes. It was found that, in the case of bending dominance, the required longitudinal reinforcements from all methods were close to each other while the BSI required much larger transverse reinforcement. In the case of torsion dominance, the BSI method required much larger longitudinal and transverse reinforcement than the both the ACI and the DDM methods. The difference in the transverse reinforcement is more pronounce. Experimental investigation showed good agreement between design and experimental failure loads of the beams designed using the Direct Design Method. Both beams failed within an acceptable range of the design loads and underwent ductile behaviour up to failure. The results indicate that the Direct Design Method can be successfully used to design partially prestressed concrete solid beams which cater for the combined effect of bending, shear and torsion loads.