• Computers and Concrete
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• v.25 no.5
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• pp.411-425
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• 2020

In this paper, the shell material has been taken as functionally graded material and their material quantity is located by the exponential volume fraction law. Moreover, the impact of ring supports around the shell circumference has been examined for their various positions along the shell axial length. These rings support restraints the radial displacement in the transverse direction. While the axial modal deformation functions have been estimated by characteristic beam functions and nature of materials used for construction of cylindrical shells. The fundamental natural frequency of cylindrical shell of parameter versus ratios of length- and height-to-radius for a wide range has been reported and investigated through the study. In addition, by increasing height-to-radius ratio resulting frequencies also increase and frequencies decrease on ratio of length-to-radius. Though the trends of frequency values of both ratios are converse to each other with three different boundary conditions. Also it is examined the position of ring supports with length-to radius ratio, height-to-radius ratio and varying the exponent of volume fraction. MATLAB software package has been utilized for extracting shell frequency spectra. The obtained results are confirmed by comparing with available literature.

• Structural Engineering and Mechanics
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• v.75 no.2
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• pp.157-174
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• 2020

In the present paper, a simple analytical model is developed based on a new refined parabolic shear deformation theory (RPSDT) for free vibration and buckling analysis of orthotropic rectangular plates with simply supported boundary conditions. The displacement field is simpler than those of other higher-order theories since it is modeled with only two unknowns and accounts for a parabolic distribution of the transverse shear stress through the plate thickness. The governing differential equations related to the present theory are obtained from the principle of virtual work, while the solution of the eigenvalue problem is achieved by assuming a Navier technique in the form of a double trigonometric series that satisfy the edge boundary conditions of the plate. Numerical results are presented and compared with previously published results for orthotropic rectangular plates in order to verify the precision of the proposed analytical model and to assess the impacts of several parameters such as the modulus ratio, the side-to-thickness ratio and the geometric ratio on natural frequencies and critical buckling loads. From these results, it can be concluded that the present computations are in excellent agreement with the other higher-order theories.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.29-32
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• 2009

Purpose: Introduction of the mammary implant through the abdominal route has been well known since late 1960s, but the use of transabdominal route for contralateral breast augmentation in transverse rectus abdominis musculocutaneous (TRAM) flap breast reconstruction patients has not been reported in Korean literature. The authors report their experience with technical points as well as the selection of the appropriate patients. Methods: Simultaneous contralateral augmentation mammaplasty through transabdominal route was performed in 11 patients who underwent TRAM breast reconstruction from August 2003 to May 2008 with a mean follow up of 27 months. The pocket was created under direct vision: 3 subglandular, 7 subpectoral, and 1 dual plane was dissected. Eight saline and 3 silicone gel implants were used with an average volume of 165 cc. Results: There were no complications such as infection, hematoma, implant displacement, and capsular contracture. The result was well maintained throughout the follow up period. Conclusion: Transabdominal route could be recommended in selected patients for contralateral augmentation in TRAM breast reconstruction.

• Journal of Korean Society of Steel Construction
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• v.12 no.4 s.47
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• pp.363-374
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• 2000

An accurate method is presented for vibrations of rhombic plates having three different combinations of clamped, simply supported, and free edge conditions. A specific feature here is that the analysis explicitly considers the moment singularities that occur in the two opposite corners having obtuse angles of the rhombic plates. Stationary conditions of single-field Lagrangian functional are derived using the Ritz method. Convergence studies of frequencies show that the corner functions accelerate the convergence rate of solutions. In this paper, accurate frequencies and normalized contours of the vibratory transverse displacement are presented for highly skewed rhombic plates, so that a significant effect of corner stress singularities nay be understood.

• Journal of Theoretical and Applied Mechanics
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• v.2 no.1
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• pp.1-14
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• 1996

In this paper, breaking waves are generated in a 2-D wave tank and simulated by using a higher-order boundary element method. A piston-type wavemaker is operated by signals composed of elementary waves. The phase of elementary waves is determined by the linear theory such that they are focused to a prescribed position. Calculated plunging waves coincide well with experiment. A steel box with different plate thicknesses is installed at a predetermined position in the tank. Measured impulsive pressures due to breaking waves are found to be 0.8-1.2$\rho$C2, where $\rho$ corresponds to water density and C to wave celerity. The transverse displacement of the plate is described in terms of modal eigenfunctions. The natural frequencies measured by impact tests in air for thin plate coincide with the computational and theoretical values. The radiationpotential due to plate vibration is derived and the radiation force is expressed in terms of hydroelastic added mass and damping forces. Comparison of natural frequencies of plate in water proves that hydroelastic added mass and damping are properly considered. The measured strain due to regular waves supports the calculated one, but there are apparent discrepancies between theory and experiment in the impulsive case.

• Journal of Dental Rehabilitation and Applied Science
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• v.23 no.4
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• pp.373-384
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• 2007

The purpose of this study was to analyse the stress distribution on the craniofacial suture and cranium after application of RME. Twelve years and six months old boy and twenty years old adult male were chosen for taking computed-tomography for FEM. From DICOM visual information, it was processed by 3-dimensional image construction program Mimics 10.01. Hounsfield unit(HU) which shows gray scale of CT image is picked for revealing mechanical properties of each model. The models have been accomplished with various range of physical properties. After applying 5.0 mm expansion, the maxillary complex model was obeserved for analyzing displacement and stress distribution of the model. The amount of transverse expansion of child and adult maxilla is different according to its location. It appears that it decreases gradually with the distance from separation site. In child, maximum compressive stress located broad area in zygomatic buttress department and the ends of frontal process of maxilla, pterygoid plate, and bones surrounding orbit. However, in adult maximum compressive stress was located smaller area and the stres was higher than child.

• Journal of Veterinary Clinics
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• v.21 no.4
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• pp.406-408
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• 2004

A nine-month-old male Jindo with non weight-bearing on the right forelimb in flexed position, pain and edema of the elbow, and resist elbow extension was brought to the Veterinary Teaching Hospital, Chungbuk National University. Elbow radiographs showed loss of humeroradial joint space and lateral displacement of the radius and ulna. Closed reduction was reported the best therapy in most cases of luxation of the elbow but conservative reduction was impossible. Open reduction of the luxated elbow was performed and ruptured collateral ligaments were identified. Displaced elbow was required bloody surgical operation and gentle reduction to restore elbow joint. Internal reduction of choice for elbow luxation with rupture of collateral ligament in the dog was a double locking-loop suture pattern. To ensure secure grasping of parallel bundles of ligament fibers to transverse bites of each suture were placed superficial to the longitudinal bites. All ligaments were repaired with 3-metric (size 2 USP) monofilament polypropylene suture. No complications have been noted during a five-month follow up.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.5
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• pp.301-310
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• 2016

There are differences in seismic behavior between non-skewed bridges and skewed bridges due to in-plane rotations caused by pounding between the skewed deck and its abutments during strong earthquake. Many advances have been made in developing design codes and guidelines for dynamic analyses of non-skewed bridges. However, there remain significant uncertainties with regard to the structural response of skewed bridges caused by unusual seismic response characteristics. The purpose of this study is performing non-linear time history analysis of the bridges using abutment-soil interaction model considering pounding between the skewed deck and its abutments, and analyzing global seismic behavior characteristics of the skewed bridges to assess the possibility of unseating. Refined bridge model with abutment back fill, shear key and elastomeric bearing was developed using non-linear spring element. In order to evaluate the amplification of longitudinal and transverse displacement response, non-linear time history analysis was performed for single span bridges. Far-fault and near-fault ground motions were used as input ground motions. According to each parameter, seismic behavior of skewed bridges was evaluated.

• Journal of Korean Foot and Ankle Society
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• v.23 no.4
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• pp.143-148
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• 2019

Although many patients who undergo bunion repair do well and have satisfactory results, a critical evaluation of these results shows the potential for improvement. Metatarsal deformity of the hallux valgus is a 3-dimensional deformity, including rotation in the coronal plane. Theoretically, it is important to understand the 3-dimensional displacement of the first metatarsal for correcting the deformities of valgus rotation in the frontal plane. Yet the current methods of metatarsal osteotomy principally attempt to correct the deformity in the transverse plane. The modified technique for the Lapidus procedure can be used in a variety of hallux valgus conditions and severities, and the early results suggest that a powerful correction can be maintained. In addition, efforts have been made to correct the 3-dimensional deformity by performing metatarsal shaft osteotomy. In the case of degenerative arthritis, first metatarsophalangeal joint arthrodesis is a good option to correct the 3-dimensional deformation. Correction of the 3-dimensional deformity, including a rotational deformity in the frontal plane of the metatarsals, should be considered when selecting surgical treatment and is essential for achieving a good prognosis for patients with hallux valgus. This article reviews the classification and treatment of hallux valgus for correction of the 3-dimensional deformity.

• Structural Engineering and Mechanics
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• v.66 no.1
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• pp.61-73
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• 2018

In this article, a higher shear deformation theory (HSDT) is improved to consider the influence of thickness stretching in functionally graded (FG) plates. The proposed HSDT has fewer numbers of variables and equations of motion than the first-order shear deformation theory (FSDT), but considers the transverse shear deformation influences without requiring shear correction coefficients. The kinematic of the present improved HSDT is modified by considering undetermined integral terms in in-plane displacements and a parabolic distribution of the vertical displacement within the thickness, and consequently, the thickness stretching influence is taken into account. Analytical solutions of simply supported FG plates are found, and the computed results are compared with 3D solutions and those generated by other HSDTs. Verification examples demonstrate that the developed theory is not only more accurate than the refined plate theory, but also comparable with the HSDTs which use more number of variables.