• Proceedings of the KSR Conference
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• 1999.11a
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• pp.209-217
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• 1999

A catenary system should be designed to be an uniform elasticity over a span in order to maintain the lowest possible loss of contact between a pantograph and a contact wire. A elasticity disuniformity of a catenary can be regarded as a important design factor used for predicting the current collection performance for a catenary. There are a couple of formulas to calculate elasticity disuniformity of a catenary according to the literature survey, The effectiveness of these formulas is reviewed by performing catenary elasticity and loss of contact analysis for 5 different configurations of catenary systems using a beam element based FEM program, KRRI developed program, and the loss of contact by GASENDO, RTRI developed program, respective]y. The results reveals that these formulas are not suitable to predict the current collection performance for a catenary. Therefore, a new formula based on the standard deviation of the elasticity over a span is proposed in this study. The analysis results show that the new formula for an elasticity disuniformity of a catenary is very effective in predicting the current collection performance for a catenary.

• Journal of Ocean Engineering and Technology
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• v.35 no.3
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• pp.238-246
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• 2021

The survivability of a naval ship is the ability of the ship and its onboard systems to remain functional and continue a designated mission in man-made hostile environments. A passive decoy system is primarily used as a weapon system for improving the survivability of a naval ship. In this study, an engagement scenario-based simulation program was developed for decoy effectiveness assessments against an anti-ship missile (ASM), which tracks a target with sea-skimming and active radar homing. The program can explain the characteristics of a target ship, such as the radar cross section and evasive maneuvers, as well as the operational performance of the onboard decoy system, the guidance method of the ASM, and the engagement environment's wind speed and direction. This paper describes the theory and formulations, configuration, and user interface of the developed program. Numerical examples of a decoy effect assessment of a virtual naval ship against an ASM are presented.

• Journal of Endocrine Surgery
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• v.18 no.4
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• pp.236-239
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• 2018

Secondary hyperparathyroidism (SHPTH) occurs commonly in patients with end-stage renal disease (ESRD). Uncontrolled SHPTH is associated with complications of calcium deposition including calciphylaxis and elevated rates of cardiovascular morbidity. Current treatment recommendations for medically refractory disease include total parathyroidectomy, often with autotransplantation (TPTH+AT) of minced parathyroid gland. Surgical intervention is associated with a reduction in cardiovascular mortality. We report a case of a 56-year-old man with ESRD who developed SHPTH and underwent TPTH+AT of parathyroid tissue into the right brachioradialis muscle. Over the course of 7 years he developed a mass at the site of the autotransplanted gland as well as recurrent refractory hyperparathyroidism with increased forearm uptake noted on sestamibi scan. After excision of this mass, pathology demonstrated hyperplasia of the minced gland fragments which were embedded within a mass of fibroadipose tissue rather than the muscle tissue it was originally transplanted in.

• International journal of steel structures
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• v.18 no.5
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• pp.1560-1576
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• 2018

With the aim to provide an efficient platform for the elastic-plastic analysis of steel structures, reinforced concrete (RC) structures and steel-concrete composite structures, a program iFiberLUT based on the fiber model was developed within the framework of ABAQUS. This program contains an ABAQUS Fiber Generator which can automatically divide the beam and column cross sections into fiber sections, and a material library which includes several concrete and steel uniaxial material models. The range of applications of iFiberLUT is introduced and its feasibility is verified through previously reported test data of individual structural members as well as planar steel frames, RC frames and composite frames subjected to various loadings. The simulation results indicate that the developed program is able to achieve high calculation accuracy and favorable convergence within a wide range of applications.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.345-354
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• 2022

The purpose of this study was to analyzed the current status of the of the Virtual Reality-based education for healthcare students in Korea. Five databases (KoreaMed, KMbase, NDSL, KISS, KiSTi) were searched prior to July 2022. A total 10 articles met the inclusion criteria. 5 articles developed VR-based education contents and the other 5 articles were using vSim already developed as a VR education program and evaluated the effectiveness. As a result of this literature review, VR-based education program was found to be effective in improving the healthcare students' competency. VR-based education program could be considered to improve the healthcare students' clinical practice ability.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.717-724
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• 2009

Most recent programs in and out of the country are related to urban renewal projects. Contemporary project management information systems have been developed was to manage single or multiple projects focusing on their construction phase, and those have limitations to apply to large-scale complicated mega projects. So, this study explain the core concept of decision support modules for iPMIS (Intelligent Program Management Information System) and its major functions to support project owner and participants by introducing ontology in the web environment. This study confined the scope of research to the planning phase of urban environment improvement projects. Ontological logic structure and relation about planning works is essential parts and three functions to implement decision support module are developed.

• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.67.1-67.1
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• 2020

Adaptive Optics (AO) is the technology for ground-based telescopes to overcome the interference caused by atmospheric turbulence. We are developing an AO system for the 1-m telescope at Seoul National University Observatory (SNUO). The seeing size of the SNUO is 2 arcseconds on average, and 0.85 arcseconds at best condition. Our system is based on MEMS deformable mirror and Shack-Hartmann wavefront sensor. We developed the wavefront sensor using a cheap CMOS camera, and measured phase disturbance at SNUO. To verify the performance of the AO system, we designed an artificial phase disturber that produces similar scale phase error, measured at SNUO. We carried out laboratory tests in which the AO system measures and corrects the wavefront using the phase disturber and an F/6 light source, the same as that of SNUO telescope. The control system was developed in C++. The system performs closed-loop PI correction up to 100 Hz at a consumer-grade PC.

• Structural Engineering and Mechanics
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• v.87 no.3
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• pp.243-254
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• 2023

Engineering structures usually suffer from cracks. The crack geometry has an influence on the structural mechanical properties and subsequent crack propagations. However, as an extensively utilized method in fracture analysis, the extended finite element method provided by Abaqus fails to output the specific location and dimensions of fractures. In this study, a technique to capture the crack geometry is proposed. The technique is based on the invariant level set method (I-LSM), which can avoid updating the level set function during crack development. The solution is achieved by an open-source plug-in programmed by Python. Three examples were performed to verify the effectiveness and robustness of the program. The result shows that the developed program can accurately output the crack geometry in both the 2D and 3D models. The open-source plug-in codes are included as supplementary material.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.20 no.1
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• pp.197-208
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• 2009

The purpose of this study is to develop a cultural program model and to provide a cultural program manual for public library. The various program models and manuals were analyzed from the literature, and program expert interviews were conducted. The results show that the culture program model includes inner factors and outer factors. Inner factors include program objective and resources as a program framework. The outer factors include program subject and format, and are what to show and how to show. A cultural program manual is developed for individual public library. The manual has 12 levels and each level has several actions which focus on important role.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.5
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• pp.1201-1206
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• 2014

Retail stores are mostly relying their product management on handwriting. This handwriting management is limited and poor at managing the status of stocking and releasing. Also, to confirm real-time product status, additional statistic system is required. POS system developed to overcome foresaid problems is operating only in big and special stores because of expensive price and limited space. Therefore, new automated management system which has low installation price needs to be developed and adopted instead of handwriting management system. In this paper, we developed real-time product management system which can manage the products in retail stores by utilizing NFC function in mobile device.