• 한국전산유체공학회:학술대회논문집
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• 2009.04a
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• pp.116-120
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• 2009

A two-dimensional unsteady inviscid flow solver has been developed for the simulation of complex geometric configurations on adaptive Cartesian meshes. Embedded condition was used for boundary condition and a predictor-corrector explicit time marching scheme was used for time-accurate numerical simulation. The Cartesian mesh generator, which was previously developed for steady problem, was used grid generation for unsteady flow. The solver was based on ALE formulation for body motion. For diminishing the effects of cut-cells, the cell merging method was used. Using cell merging method, it was eliminated the CFL constraints. The conservation problem, which is caused cell-type variation around region swept by solid boundary, was also solved using cell merging method. The results are presented for 2D circular cylinder and missile launching problem.

• Structural Engineering and Mechanics
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• v.43 no.4
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• pp.439-448
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• 2012

This paper investigates the load sharing of double circular arc helical gears considering the influence of assembly errors. Based on a load sharing formulae, a three-dimensional finite element tooth contact analysis (TCA) is implemented with commercial software package ANSYS. The finite element grid for the double circular arc gear contact model is automatically generated by using the APDL (ANSYS Parameter Design Language) embedded in ANSYS. The realistic rotation of gears is achieved by using a coupling degree-of-freedom method. Numerical simulations are carried out to exemplify the proposed approach. The distribution of contact stress and bending stress under specific loading conditions are computed and compared with those obtained from Hertz contact theory and empirical formulae to demonstrate the efficiency of the proposed load sharing calculation formulae and TCA approach.

• Journal of information and communication convergence engineering
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• v.8 no.6
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• pp.709-715
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• 2010

This paper represents a map building and localization system for mobile robot. Map building and navigation is a complex problem because map integrity cannot be sustained by odometry alone due to errors introduced by wheel slippage, distortion and simple linealized odometry equation. For accurate localization, we propose sensor fusion system using encoder sensor and indoor GPS module as relative sensor and absolute sensor, respectively. To build a map, we developed a sensor based navigation algorithm and grid based map building algorithm based on Embedded Linux O.S. A wall following decision engine like an expert system was proposed for map building navigation. We proved this system's validity through field test.

• Journal of Power System Engineering
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• v.9 no.1
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• pp.23-29
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• 2005

Numerical analysis of three-dimensional viscous flow-fields in the turbine rotor passages was carried out to investigate flow physics including the interaction between secondary vortices, tip leakage vortex, and the rotor wake. The blade tip geometry was accurately modeled adopting the embedded H grid system. An explicit four-stage Runge-Kutta scheme was used for the time integration of both the mean flow and turbulence equations. The computational results for the entire turbine rotor flows, particularly the tip clearance flow and the secondary flows, were interpreted and compared with the experimental data from the Penn State turbine stage. The predictions for major features of the flow field have been found to be in good agreement with the experimental data.

• 한국전산유체공학회:학술대회논문집
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• 2003.08a
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• pp.171-175
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• 2003

Numerical analysis of three-dimensional viscous flow-fields in the turbine rotor passages is carried out to investigate flow physics including the interaction between secondary vortices, tip leakage vortex, and the rotor wake. The blade tip geometry is accurately modeled adopting the embedded H grid topology. An explicit four-stage Runge-Kutta scheme is used for the time integration of both the mean flow and turbulence equations. The computational results for the entire turbine rotor flows, particularly the tip clearance flow and the secondary flows, are interpreted and compared with the experimental data from the Penn State turbine stage. Good agreement between the experimental data and the numerical prediction was achieved in the sense of the major features of the flow fields.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.13-17
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• 2004

In recent years, the deterioration of reinforced concrete structures has become a serious problem in civil engineering fields. This situation is mainly due to corrosion of steel reinforcing bars embedded in concrete. Recently, there has been a greatly increased demand for the use of FRP (fiber reinforced plastic) in civil engineering field due to their superior mechanical and physical properties. This paper presents an experimental study on the behavior of concrete bridge deck reinforced with FRP Box, FRP Plate, and FRP Re-bar. In tlIe study, mechanical properties of FRP Box, FRP Plate, GFRP Re-bar, and CFRP Grid have been investigated. Full scale one-way deck slab was tested under four point lateral load (equivalent to actual wheel load of DB-24 including impact). Load-deflection and load-strain data were collected through LVDT's and strain gages attached to the specimen.

• Journal of Advanced Navigation Technology
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• v.17 no.6
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• pp.664-671
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• 2013

In this paper, in an aircraft power can be measured by wireless AEMS (aircraft electric power measurement monitoring system) system is proposed. AEMS has been design based on current commercialized power measuring systems analysis with improvement and connects it with most talked about item, smart phone and monitoring system. And also adopting real time power measuring system, constitute more practical power measuring system by controlling electricity usage in real time.

• Journal of architectural history
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• v.12 no.1 s.33
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• pp.25-41
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• 2003

This paper is a study of Le Corbusier's trace regulateur of the 1920s, particularly its role in the design of the Villas La Roche-Jeanneret and Stein-de Monzie. It proceeds on the basis of the following three themes: first, the relation between the regulating line and the dom-ino frame; second, its status as a proportional device based not on a module system but one that defines relations; third, its function as an essential practical device in the design process. In the Villa La Roche-Jeanneret, the embedded horizontal planes of the dom-ino frame were constant, but the vortical lines of the columns were altered according to the changes in plan. Initially, a left-hand bay window formed a symmetry with the right-hand bay window, the only constant in the design process. With subsequent changes, mullion sections of the horizontal window and roof elements came to provide the reference points for the regulating line. Eventually, a regulating line different from the one that controlled the bay window and the elongated volume came to control the entrance hall of Villa La Roche, resulting in three different kinds of regulating lines in the final version. In contrast to the Villa La Roche-Jeanneret, a singular and consistent regulation line was anticipated in the earliest design stages of the Villa Stein-de Monzie. The repetition of its A:B grid and the standard $2.5m{\times}1.0m$ sliding window determined the proportions of both its plan and elevation, and thus the regulating line became 'automatic,' losing its viability as a practical tool. Though the regulating titles of the La Roche-Jeanneret look as if they were an afterthought, drawn after the design was complete, they were most active, requiring tenacity and discipline in their application. On the other hand, the seemingly 'redundant' regulating line of the Villa Stein-de Monzie gains its raison d'etre from the dom-ino frame. Its cantilevers and uninterrupted horizontal window could be used in decisive fashion because of the guarantee that the correct proportion would always be maintained. Thus we discover that Le Corbusier's discipline of the 1920s had a certain spectrum of flexibility. His 'parti' ranged from the extremely loose and malleable grid of the Villa La Roche-Jeanneret to the fixed grid of the Villa Stein-de Monzie. In different ways, these projects retain the tension between the dom-ino frame and the regulating line. For Le Corbusier, as much as the grid was an object with fixed attributes, it was also an active medium manipulated by the will of the architect.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.8
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• pp.685-692
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• 2007

This paper describes the development procedure of GUI Program for the automated generation of airfoil performance table used in helicopter comprehensive code. Considering commercialization, the program is developed based on the Windows operating system. In addition, it is aimed to enhance user's convenience by including embedded postprocessor which enables real-time display of calculation procedure and grid system. Using the validated CFD code, the aerodynamic analyses are automated for a given range of Mach number and angles of attack. The computational grid system is designed to generate automatically once the surface coordinates are given. Mixed-Language scheme is employed in order to combine the CFD code in Fortran with C++ based GUI program, which makes the time-consuming code conversion unnecessary.

• The KIPS Transactions:PartA
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• v.10A no.4
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• pp.389-396
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• 2003

InfiniBand technology is being accepted as the future system interconnect to serve as the high-end enterprise fabric for cluster computing. This paper presents the design and implementation of the InfiniBand system interconnect, focusing on an InfiniBand host channel adapter (HCA) based on dual ARM9 processor cores The HCA is an SoC tailed KinCA which connects a host node onto the InfiniBand network both in hardware and in software. Since the ARM9 processor core does not provide necessary features for multiprocessor configuration, novel inter-processor communication and interrupt mechanisms between the two processors were designed and embedded within the KinCA chip. Kinch was fabricated as a 564-pin enhanced BGA (Bail Grid Array) device using 0.18${\mu}{\textrm}{m}$ CMOS technology Mounted on host nodes, it provides 10 Gbps outbound and inbound channels for transmit and receive, respectively, resulting in a high-performance cluster system.