• Journal of the Society of Naval Architects of Korea
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• v.48 no.5
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• pp.451-456
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• 2011

To ensure structural integrity of membrane type LNG tank, the rational assessment of the sloshing impact responses of tank structures should be preceded. The sloshing impact pressures acting on the insulation system of LNG tank are typical irregular loads and the resulting structural responses show very complex behaviors accompanied with fluid structure interaction. So it is not easy to estimate them accurately and immense time consuming calculation process would be necessary. In this research, a simplified method to analyse the dynamic structural responses of LNG tank insulation system under pressure time histories obtained by sloshing model test or numerical analysis was studied. The proposed technique based on the concept of linear combination of the triangular response functions which are the transient responses of structures under the unit triangular impact pressure acting on structures. The validity of suggested method was verified through the example calculations and applied to the dynamic structural response analysis of a real Mark III membrane type insulation system using the sloshing impact pressure time histories obtained by model test.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.819-827
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• 2019

Bragg reflection of water waves by three kinds of surface-piercing fixed structures with rectangular, cosinoidal and triangular shapes is studied. Boundary element method is used to analyze the wave scattering by these structures based on the linear wave theory. Results of reflection and transmission coefficients are validated by comparing with those available in literature. These structures with proper configurations are proved to be effective in attenuating waves by using Bragg reflection, and the triangular structures are found to be the best choices among the structures with same width and same area. Systematic calculations are then carried out for the triangular structures by varying the number, the draft, the width, the gap and the combination of width and gap of the structures to analyze their influences on the characteristics of Bragg reflection. The results are of reference values for design of the structures to attenuate waves based on the Bragg reflection.

• Advances in pediatric surgery
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• v.6 no.1
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• pp.19-26
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• 2000

This paper reports our 9-year experience treating 34 infants with biliary atresia utilizing a new non-invasive diagnostic method, ultrasonographic "triangular cord"(TC) sign. The TC sign is present when there is visualization of a triangular or a band-like echogenicity just cranial to the portal vein. The ultrasonographic TC sign appears to be a simple, non-invasive, time-saving and useful tool in the diagnosis of biliary atresia. Sensitivity is 84 %. Active bile excretion was restored in 90 % of the patients who were treated between 31-60days, 78 % of those between 61-90 days, and 33 % of those being 91days or older. The incidence of postoperative cholangitis was 36 %. Construction of an antireflux valve in the Roux-en-Y loop did not affect the incidence of postoperative cholangitis(p=0.18). Among 34 infants with biliary atresia, 23(68 %) are alive for 2-102 months after operation, and 12 are alive for more than 5 years. Five-year estimate survival by Kaplan-Meier method was 66 %.

• Wind and Structures
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• v.29 no.1
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• pp.43-53
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• 2019

Vortex-induced vibration of three circular cylinders (each of diameter D) in an equilateral triangular arrangement is investigated using the immersed boundary method. The cylinders, with one placed upstream and the other two side-by-side downstream, are free to vibrate in the cross-flow direction. The cylinder center-to-center spacing L is adopted as L/D = 2.0. Other parameters include the Reynolds number Re = 100, mass ratio $m^*=2.0$, reduced velocity $U_r=2{\sim}15$ and damping ratio ${\zeta}=0$. Cylinder vibration responses are dependent on $U_r$ and classified into five regimes, i.e. Regime I ($U_r{\leq}3.2$), Regime II ($3.2<U_r{\leq}5.0$), Regime III ($5.0<U_r{\leq}6.4$), Regime IV ($6.4<U_r{\leq}9.2$) and Regime V ($U_r>9.2$). Different facets of vibration amplitude, hydrodynamic forces, wake patterns and displacement spectra are extracted and presented in detail for each regime.

• Proceedings of The Korean Cleft Lip And Palate Association
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• 2002.02a
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• pp.49-58
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• 2002

• Journal of the Korean Society for Precision Engineering
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• v.23 no.7 s.184
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• pp.187-193
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• 2006

This paper introduces and illustrates the results of a new method for offsetting the triangular mesh generated from multiple surfaces. The meshes generated from each surface are separated each other and normal directions are different. The face normal vectors are flipped to upward and the lower faces covered by upper faces are deleted. The virtual normal vectors are introduced and used to of feet boundary. It was shown that new method is better than previous methods in offsetting the triangular meshes generated from multiple surfaces. The introduced offset method was applied for 3-axis tool path generation system and tested by NC machining.

• Proceedings of the KIEE Conference
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• 1998.07g
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• pp.2209-2211
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• 1998

This paper presents the matching algorithm with the satellite images using the image warping method. Two stereo images, which are used for the DEM(Digital Elevation Model) extraction, are generally distorted because the images are acquired at different locations and angles. Therefore, the matching Process can't be executed with the original images. To solve this problem, a dynamic triangular image warping method is proposed. At first, the initial matching is executed with seed point, and then, using the matched points from the initial matching, the distorted images is compensated. We experimented this algorithm with the parts of the $6000{\times}6000$ SPOT satellite images. The experiment results show this algorithm is superior to other warping algorithm.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.5
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• pp.849-863
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• 1992

A very simple and computationally efficient numerical method is developed for the free vibration of isotropic and orthotropic composite triangular plates. A set of two-dimensional simple series functions is used as an admissible displacement functions in the Rayleigh-Ritz method to obtain the natural frequencies, nodal patterns and mode shapes for the plates. From the prescribed starting function satisfying only the geometric boundary conditions, the higher terms in the series functions are constructed with adding order of polynominal. Natural frequencies, nodal patterns and mode shapes are obtained for right triangular plates with three different support conditions. The obtained numerical results are presented, and the isotropic and some orthotropic cases are verified with other numerical methods in the liternature.

• Journal of the Korea Concrete Institute
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• v.28 no.6
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• pp.713-722
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• 2016

The goal of this study was to assess the seismic performance of hollow cast-in-place and precast reinforced concrete bridge columns with triangular reinforcement details. The developed material quantity reduction details are economically feasible and rational, and facilitate shorter construction periods. By using a sophisticated nonlinear finite element analysis program, the accuracy and objectivity of the assessment process can be enhanced. The used numerical method gives a realistic prediction of seismic performance throughout the input ground motions for several hollow column specimens investigated. As a result, triangular reinforcement details were designed to be superior to the existing reinforcement details in terms of required seismic performance.

• Archives of Plastic Surgery
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• v.48 no.6
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• pp.614-621
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• 2021

Background Reconstruction of congenital microtia remains challenging, particularly in patients with a history of ear canaloplasty due to insufficient regional soft tissue. The insertion of a tissue expander prior to implantation of the cartilage framework has traditionally been employed. However, this procedure could induce additional morbidity. Herein, we present a method using V-Y advancement of a temporal triangular flap to gain additional soft tissue in these challenging cases. Methods Congenital microtia patients with a history of ear canaloplasty who underwent auricular reconstruction using the Nagata technique between 2016 and 2020 were reviewed. To obtain additional soft tissue, V-Y advancement of a temporal triangular flap was performed concurrently with implantation of the costal cartilage framework, without prior insertion of a tissue expander. The outcomes of these patients with respect to postoperative complications and esthetics were evaluated. Results Eight patients with bilateral lesions were included. No specific complications developed after the first-stage surgery. However, one patient experienced complications after the second stage (auricular elevation). An analysis of the esthetic results showed most patients had excellent outcomes, achieving a satisfactory convolution. The median number of operations needed to complete reconstruction was 2, which was fewer than required using the conventional method with prior insertion of a tissue expander. Conclusions In patients with a history of previous canaloplasty, V-Y advancement of a temporal triangular flap could serve as an alternative to tissue expansion for microtia reconstruction. This technique provided reliable and satisfactory results with a reduced number of surgical stages.