• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2003.10a
• /
• pp.119-119
• /
• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2003.10a
• /
• pp.87-87
• /
• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2003.10a
• /
• pp.132-132
• /
• 2003

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.12 no.2
• /
• pp.127-138
• /
• 2012

In this paper, we propose a real-time virtual re-convergence hardware platform especially to reduce the visual fatigue caused by stereoscopy. Our unique idea to reduce visual fatigue is to utilize the virtual re-convergence based on the optimized disparity-map that contains more depth information in the negative disparity area than in the positive area. Our virtual re-convergence hardware platform, which consists of image rectification, disparity estimation, depth post-processing, and virtual view control, is realized in real time with 60 fps on a single Xilinx Virtex-5 FPGA chip.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.11 no.2
• /
• pp.835-850
• /
• 2019

The numerical simulations for the Vortex-induced Vibration (VIV) of the cylinders with different combinations of mass ratio and frequency ratio were performed under the Reynolds (Re) number ranges of 1450-10200, 5800-40800 and 13050-91800 by using the embedded programs in OpenFoam. By combining with the modified SST k-ω turbulence model, the coupled Unsteady Reynolds-Average Navier-Stokes equations and double-degree-of-freedom vibration equations were solved. After analyzing the results, it is found that the some characteristics of the VIV have changed with the increase of the range of Re number, and the effects of Re number on vibration characteristics are also different under different combinations of mass ratio and frequency ratio. On this basis, the influence law of Re number on the characteristics of VIV of the cylinders is summarized, which can provide a reference for the research of VIV under higher Re number.

• Journal of KIISE:Software and Applications
• /
• v.29 no.9
• /
• pp.619-630
• /
• 2002

The various software engineering techniques have been come out in order to cope with the software crisis since 1980's. The software Engineering has focused on the process of software component development. The process products a development guide for a quality and productive improvement of software. But, most of the methodologies assume that a new system will be constructed and reused in the future. these do not actually support efficiently how we reuse legacy system's resources and construct a new system. In this paper, we present an efficient Reengineering Process for reusing legacy systems, RUP+re, which extends and customizes RUP. Rup+re consists of Reverse Engineering Workflow, Re-Engineering Workflow and forward Engineering Process. We describe RUP+re's workflows with their own detail steps and verify them practically through the case study. So, we provide efficient guidelines to the software Reengineering process construction which reuses the resources of a legacy system.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.10 no.4
• /
• pp.477-490
• /
• 2018

Effects of inflow Reynolds number (Re), turbulence intensity (I) and pressure gradient on the transition flow over a blade section were studied using the ${\gamma}-Re{\theta}$ transition model (STAR-CCM+). Results show that the $Re_T$ (transition Re) at the transition location ($P_T$) varies strongly with Re, I and the magnitude of pressure gradient. The $Re_T$ increases significantly with the increase of the magnitude of favorable pressure gradient. It demonstrates that the $Re_T$ on different blade sections of a rotating propeller are different. More importantly, when there is strong adverse pressure gradient, the $P_T$ is always close to the minimum pressure point. Based on these conclusions, the $P_T$ on model propeller blade surface can be estimated. Numerical investigations of pressure distribution and transition flow on a propeller blade section prove these findings. Last, a simple method was proposed to estimate the $P_T$ only based on the propeller geometry and the advance coefficient.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09a
• /
• pp.686-687
• /
• 2006

The encapsulated induction melting and hot pressing were employed to prepare Fe-doped $CoSb_3$ skutterudites and their thermoelectric properties were investigated. Single phase $\delta-CoSb_3$ was successfully obtained by the subsequent heat treatment at 773K for 24 hours. Iron atoms acted as electron acceptors by substituting cobalt atoms. Thermoelectric properties were remarkably improved by the appropriate doping. $Co_{0.7}Fe_{0.3}Sb_3$ was found as an optimum composition for best thermoelectric properties in this work.

• Journal of the Korean Ceramic Society
• /
• v.42 no.11 s.282
• /
• pp.763-769
• /
• 2005

Ferroelectric $ReMnO_3$(Re:Ho, Er) thin films were deposited on Si(100) substrate by Metal-Organic Chemical Vapor Deposition (MOCVD). Crystallinity and electric properties of $ReMnO_3$(Re:Ho, Er) thin films were investigated as a function of thermal heat treatment process, CHP (Conventional Heat-treatment Process) and RTP (Rapid Thermal Process). $ReMnO_3$(Re:Ho, Er) thin films prepared by RTP showed higher c-axis preferred orientation and homogeneous surface roughness than those prepared by CHP. The remnant polarization of ferroelectric hysteresis loop of $ReMnO_3$(Re:Ho, Er) thin films was strongly dependent on the c­axis preferred orientation of hexagonal single phase, and the leakage current characteristics of thin films were dependent on the homogeneity of grain size as well as surface roughness of thin films.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.361-364
• /
• 1997

The re-enty guidance design involves trajectory optimization, generation of a reference drag acceleration profile with the satisfaction of trajectory constraints. This reference drag acceleration profile can be considered as the reference trajectory. This paper proposes the atmospheric re-entry system which is composed of longitudinal, later and range control. This paper shows the a performance of a re-entry guidance and control system using feedback linearization control and predictive control.