• Journal of Information Technology Services
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• v.10 no.3
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• pp.95-112
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• 2011

This paper proposes a new registry model for systematically referencing standards in e-Business field. We have many systems that provide standards and additional information. However, there are several problems such as inefficient standard information, dependency on a standard type, high standard information acquisition cost, no relations between standard information, and so on. In this paper, a new registry model and its prototype implementation are described. The proposed model is defined based on ISO/IEC 11179-Metadata registries, which is one of the international standards for interoperability between data. The proposed model provides an integrated- systematic standard information support, and also considers technology stack and business processes for e-Business systems. This paper develops a prototype for the proposed model and implementation result. Finally, to show the contribution of our proposal, this paper shows the comparative evaluation between previous systems and our proposal with various comparative items.

• Journal of the korean Society of Automotive Engineers
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• v.11 no.5
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• pp.76-89
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• 1989

With the objective of studying the response of brain tissue in a transient rotational acceleration of the head, as occurs in car crash, the problem of a cylindrical case containing a prototype brain material of silicone gel and subjected to a rotational acceleration around the axis of the cylinder is analysed. The prototype material is considered to be homogeneous and isotropic, and is modeled alternatively as a linear elastic or a linear viscoelastic solid. The computational model for the present problem consists of a 3-dimensional isoparametric finite element model, wherein large deformations and large strains are treated through the updated Lagrangian approach. A comparison of the results of the present 3-dimensional computations, with the attendant assumptions on material data, is made with the results of independent experimental study. The deformation profiles and the major characteristics of response of the brain material are in good agreement with the test results. Moreover, the study suggests the possibility that the use of more accurate material data may yield very useful results even appropriate for accurate quantification of deformations.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.8 no.1
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• pp.1-7
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• 2012

A PHE (Process Heat Exchanger) is a key component required to transfer heat energy of $950^{\circ}C$ generated in a VHTR (Very High Temperature Reactor) to the chemical reaction that yields a large quantity of hydrogen. A small-scale PHE prototype made of Hastelloy-X is being tested in a small-scale gas loop at Korea Atomic Energy Research Institute. In order to properly evaluate the high-temperature structural integrity of the small-scale PHE prototype, it is very important to impose a proper constraint condition on its structural analysis model. For this effort, we tried to impose several constraint conditions on the structural analysis model and consequently fixed a proper and effective displacement constraints.

• Wind and Structures
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• v.20 no.6
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• pp.811-827
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• 2015

This study presents experimental and numerical aerodynamic investigation of a prototype vehicle. Aerodynamics forces examined which exerted on a prototype. This experimental study was implemented in a wind tunnel for the Reynolds number between $10^5-3.1{\times}10^5$. Numerical aerodynamic analysis of the vehicle is conducted for different Reynolds number by using FLUENT CFD software, with the k-$\varepsilon$ realizable turbulence model. The studied model aims at verifying the aerodynamic forces between experimental and numerical results. After the Reynolds number of $2.8{\times}10^5$, the drag coefficient obtained experimentally becomes independent of Reynolds number and has a value of 0.25.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.6
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• pp.131-137
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• 2007

In metal casting process, it is very difficult to predict the form accuracy of cast part and reduce repeatability error. In this study, the variations of form accuracy were measured in the process of metal cast prototyping, where RP part is manufactured from CAD model in the first, and then, wax part is cast in the vacuum environment using the RP part as master model, and finally metal prototype is cast using ceramic mold and the wax part as pattern. To investigate the variations of form accuracy, the averages and standard deviations of error distribution of the parts measured by 3D scanner were compared. It was observed that the biggest shrinkage is generated during the extraction of wax part in the second step and the biggest deterioration of form accuracy is generated during the metal part casting in the last step.

• International journal of advanced smart convergence
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• v.8 no.1
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• pp.58-64
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• 2019

In recent years, small mobile devices called personal mobility or smart mobility have attracted attention. Personal mobility refers to electric-driven personal transportation that can travel at close range and medium distance, including small electric vehicles, electric bicycles, electric motorcycles and electric scooters. Most of the electric scooters used in Korea are mainly imported from China. This is due to the fact that the price competitiveness of major components of electric scooters is owned in China. At this point, the domestic research direction is preferable for the composition and design of the electric scooter body rather than cost reduction for the components. In this study, we propose a new model of portable folding structure that is easy to use for electric scooters, which are personal vehicles using electric energy. We also made a prototype for practical use.

• International journal of advanced smart convergence
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• v.12 no.4
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• pp.451-457
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• 2023

Global warming is causing abnormal climates such as floods, droughts, and typhoons all over the world. According to some scientists, carbon dioxide emitted from automobiles is the main cause of global warming. To cope with this, each country is making efforts to replace the existing fossil fuel-powered engine-driven cars with electric vehicles. In order to commercialize small electric vehicles in Korea, it is necessary to solve many problems such as improvement of hill climbing capacity and improvement of power performance. In this study, we propose a proprietary model for a continuously variable transmission(CVT) of a small electric vehicle that can be operated on hills, in which a spring is mounted on a driving pulley and a driven pulley. A prototype of the CVT model using a spring was manufactured and attached to a small electric vehicle body.

• Explosives and Blasting
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• v.25 no.1
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• pp.53-65
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• 2007

When doing a blasting demolition on RC structures made of scale models, scale model members considering both a proper scale factor and mechanical characteristics of materials have to be similar to prototype RC members to analyze the collapse behavior of RC structures. In this study. a similitude law considering the density of prototype materials is calculated. Both mix of concrete and arrangement of reinforcement have been described referring to Concrete Standard Specification as well as Design Standard of Concrete Structure. The scale factor on scaled concrete models considering maximum size of coarse aggregate is about one-fifth of a cross section of prototype concrete members. A scale factor on staled steel bar models is about one-fifth of a nominal diameter of prototype steel bar. According to the mechanical test results of scale models, it can be concluded that the modified similitude law may be similar to compressive strength of prototype concrete and yield strength of prototype steel bar.

• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.661-665
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• 2010

Current subway station's office employee must perform safety management tasks by monitoring the various safety management systems. But these monitoring systems are limited in effective situational awareness and response to a state of emergency immediately. It is necessary to develop an integrated safety management system display. In this study, we developed subway station safety management system's (CCTV, fire detection & alarm system, screen door control equipment) integrated prototype display with ecological interface design framework and evaluated prototype display interface's usability with GOMS model. The result was that the ecological interface's performance was better than existing safety management system's interface.

• Magazine of the Korea Concrete Institute
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• v.8 no.3
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• pp.177-185
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• 1996

Four types of experiments were performed to check the similitude of member behavior between prototype and 1 /10 scale models : (1) Test of slender columns with P-$\Delta$ effect, (2) Test of short columns with and without confinement steel, (3) Test of simple beams without stirrups, and (4) 'T-beam test. Based on the results of experiments, the conclusions were made as follows : (1) The P-$\Delta$ effect of slender columns can be almost exactly represented by 1/10 scale model. (2) The effect of confinement on short columns by the hoop steel can be also roughly simulated by 1/10 scale model. (3) The failure modes of simple beams without stirrups are brittle shear failures in prototype whereas those of 1/10 scale models are the ductile yielding of tension steel followed by large diagonal tension cracking and compressive concrete failure. (4) The behaviors of prototype and 1/10 scale model in T-beams appear very similar.