• Journal of applied mathematics & informatics
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• v.13 no.1_2
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• pp.11-27
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• 2003

A fourth order in time and second order in space scheme using a finite-difference method is developed for the non-linear Boussinesq equation. For the solution of the resulting non-linear system a predictor-corrector pair is proposed. The method is analyzed for local truncation error and stability. The results of a number of numerical experiments for both the single and the double-soliton waves are given.

• Journal of applied mathematics & informatics
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• v.8 no.3
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• pp.683-691
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• 2001

A linearized finite-difference scheme is used to transform the initial/boundary-value problem associated with the nonlinear Schrodinger equation into a linear algebraic system. This method is developed by replacing the time and the nonlinear term by an appropriate parametric linearized scheme based on Taylor’s expansion. The resulting finite-difference method is analysed for stability and convergence. The results of a number of numerical experiments for the single-soliton wave are given.

• Journal of the Korean Society of Marine Environment & Safety
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• v.4 no.1
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• pp.1-12
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• 1998

The Ministry of Maritime Affairs and Fisheries embarked on Oct. 8, 1996, incorporating most of the previously fragmented maritime administrations into one single organization But the maritime administrative functions related to safely and security missions have not yet been merged into a synergetic whole, with versatile multi-functional systems working so effectively that better services to the public might be expected. Enhancing administrative capabilities requires that these missions be integrated into one institution and an enterprising management system be adopted to overcome bureaupathologies, such as complacency and inertness of administration.

• Wind and Structures
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• v.7 no.1
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• pp.29-40
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• 2004

This study has focused on aerodynamics for a wind-resistance design about the single and tandem box girder sections to realize a super-long span bridge in the near future. Three-dimensional static analysis of flows around the fundamental single and tandem box girder sections with fairing is carried out by means of the IBTD/FS finite element technique with LES turbulence model. As the results of the analysis, computations have verified aerodynamic characteristics of both sections by the histories of aerodynamic forces, the separation and reattachment flow patterns and the surface pressure distributions. The relationship between the section shapes and the aerodynamic characteristics is also investigated in both sections. And the mechanism about the generation of fluctuating aerodynamic forces is discussed.

• Structural Engineering and Mechanics
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• v.26 no.3
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• pp.231-250
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• 2007

The influence of masonry infills with eccentric openings on the seismic performance of reinforced concrete (r/c) frames that were designed in accordance with current code provisions are investigated. Eight 1/3-scale, single-story, single-bay frame specimens were tested under cyclic horizontal loading up to a drift level of 4%. In all examined cases the shear strength of columns was higher than the cracking shear strength of solid infill. The parameters investigated include the shape and the location of the opening. Assessment of the behavior of the frames is also attempted, based on the observed failure modes, strength, stiffness, ductility, energy dissipation capacity and degradation from cycling loading. Based on these results there can be deduced that masonry infills with eccentrically located openings has been proven to be beneficial to the seismic capacity of the bare r/c frames in terms of strength, stiffness, ductility and energy dissipation. The location of the opening must be as near to the edge of the infill as possible in order to provide an improvement in the performance of the infilled frame.

• Structural Engineering and Mechanics
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• v.31 no.4
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• pp.423-437
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• 2009

In order to perform a step-by-step force-displacement response analysis or dynamic time-history analysis of large buildings with masonry infilled R/C frames, a continuous force-deformation model based on an equivalent strut approach is proposed for masonry infill panels containing openings. The model, which is applicable for degrading elements, can be implemented to replicate a wide range of monotonic force-displacement behaviour, resulting from different design and geometry, by varying the control parameters of the model. The control parameters of the proposed continuous model are determined using experimental data. The experimental program includes fifteen 1/3-scale, single-story, single-bay reinforced concrete frame specimens subjected to lateral cyclic loading. The parameters investigated include the shape, the size, the location of the opening and the infill compressive strength. The actual properties of the infill and henceforth the characteristics needed for the diagonal strut model are based on the assessment of its lateral resistance by the subtraction of the response of the bare frame from the response of the infilled frame.

• Journal of Veterinary Science
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• v.23 no.4
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• pp.59.1-59.5
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• 2022

Korean Institutional Animal Care and Use Committee (IACUC) is currently facing some operational pressing issues. 1) Review of the animal protocol containing controversial technology. 2) Review of the multi-institution animal protocol. 3) Review of veterinary clinical trials for client-owned animals. 4) Delay in the review process in large institutions with a single IACUC. Here, the following three solutions are proposed to address the above issues. 1) Establishment of public IACUC. 2) Establishment of the Veterinary Clinical Study Committee as an advisory body to the IACUC. 3) Operating multiple committees rather than increasing the number of committee members on a single committee.

• Journal of Yeungnam Medical Science
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• v.27 no.2
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• pp.165-172
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• 2010

Primary thyroid lymphoma is a relatively rare thyroid tumor and usually a non-Hodgkin type. Its most common histologic type is the diffuse large B cell lymphoma followed by mucosa-associated lymphoid tissue(MALT). It is known to be frequently associated with autoimmune thyroiditis such as Hashimoto's thyroiditis. We report three cases of thyroid lymphoma at a single institution with are view of the literature.

• Journal of Gastric Cancer
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• v.12 no.4
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• pp.237-242
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• 2012

Purpose: Despite the great advances in laparoscopic techniques, most active general surgeons do not apply laparoscopic surgery in the treatment of duodenal ulcer perforation when facing a real-life emergency. Therefore, our study was designed to evaluate the feasibility of laparoscopic surgery in duodenal ulcer perforation, and provide a step-by-step protocol with tips and recommendations for less experienced surgeons. Materials and Methods: Between March, 2011 and May, 2012, 21 patients presenting with duodenal ulcer perforation underwent laparoscopic primary repair with omentopexy. There were no contraindications to perform laparoscopic surgery, and the choice of primary repair was decided according to the size of the perforation. The procedure for laparoscopic primary repair with omentopexy consisted of peritoneal lavage, primary suture, and omentopexy using a knot pusher. Results: During the operation, no conversion to open surgery or intra-operative events occurred. The median operation time was 45.0 minutes (20~80 minutes). Median day of commencement of a soft diet was day 6 (4~17 days). After surgery, the median hospital stay was 8.0 days (5~27 days). Postoperative complications occurred in one patient, which included a minor leakage. This complication was resolved by conservative management. Conclusions: Although our study was carried out on a small number of patients at a single institution, we conclude that laparoscopic primary repair can be an effective surgical method in the treatment of duodenal ulcer perforation. We believe that the detailed explanation of our procedure will help beginners to perform laparoscopic primary repair more easily.

• Korean Journal of Head & Neck Oncology
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• v.36 no.2
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• pp.1-7
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• 2020

Background/Objectives: Pediatric & Adolescent thyroid cancer is a steadily increasing malignancy. We aimed to report our experience at a single tertiary institution and to evaluate the risk factors for recurrence in pediatric & adolescent patients with differentiated thyroid carcinoma (DTC). Materials & Methods: The data of 42 pediatric & adolescent patients (aged ≤19 years) with DTC who underwent thyroidectomy at Seoul St. Mary's Hospital (Seoul, Korea) between December 1997 and February 2019 were retrospectively reviewed. Clinicopathologic features and surgical outcomes were retrospectively analyzed through complete chart reviews. Results: The mean age was 16.6 years. A total of 6 (14.3%) patients experienced recurrence after initial treatment. The recurrence rate was significantly different between total thyroidectomy (TT) and lobectomy groups (23.1% vs. 0%, p=0.038). However, no statistically significant differences were found in the recurrence rate according to lymph node ratio (LNR) of 0.4 (10.7% vs 21.4%; P=0.383). Multivariate analysis confirmed age (hazard ratio [HR], 0.443; P=0.008) and bilaterality (HR, 11.477; P=0.022) as significant risk factors for DFS. Conclusion: Pediatric & Adolescent thyroid cancer is a rare malignancy and TT is recommended as the treatment of choice. However, lobectomy may be considered for Pediatric & Adolescent patients with age >16 years, tumor size <1 cm, and no bilateral disease.