• Transactions of Materials Processing
• /
• v.9 no.4
• /
• pp.404-412
• /
• 2000

It is desirable to use the square grid analysis with the aid of the stereo vision and image processing techniques in order to automatically measure the surface-strain distribution over a stamped part. But this method has some inherent problems such as the difficulty in enhancement of bad images, the measurement error due to the digital image resolution and the limit of the area that can be measured at a time. Therefore, it is still hard to measure the strain distribution over the entire surface of a medium-or large-sized stamped part even by using an automated strain measurement system. In this study, several methods which enable to solve these problems considerably without losing accuracy and precision In measurement are suggested. The superposition of images that have different high-lightened or damaged part from each other gives much enhanced image. A new algorithm for constructing of the element connectivity from the line-thinned image helps recognize up to 1,000 elements. And the geometry assembling algorithm including the global error minimization makes it possible to measure a large specimen with reliability and efficiency.

• Transactions of the Korean Society of Mechanical Engineers B
• /
• v.25 no.8
• /
• pp.1140-1147
• /
• 2001

Experimental schemes that enable characterization of phase-change phenomena in the microscale regime are essential for understanding the phase-change kinetics. Particularly, monitoring rapid vaporization on a submicron length scale is an important yet challenging task in a variety of laser-processing application, including steam laser cleaning and liquid-assisted material ablation. This paper introduces a novel technique based on Michelson interferometry for probing the liquid-vaporization process on a solid surface heated by a KrF excimer laser pulse(λ=248nm, FWHM=24ns) in water. The effective thickness of a microbubble layer has been measured with nanosecond time resolution. The maximum bubble size and growth rate are estimated to be of the order of 0.1㎛ and 1m/s, respectively. The results show that the acoustic enhancement in the laser induced vaporization process is caused by bubble expansion in the initial growth stage, not by bubble collapse. This work demonstrates that the interference method is effective for detecting bubble nucleation and microscale vaporization kinetics.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.10 no.2
• /
• pp.37-44
• /
• 1992

Although scanners are much more expensive than other input devices expect for some low quality devices, raster scanner and vectorizing softwares have been used and will be used as a means for the data entry in GIS. In this study, the accuracy of raster data and vectorizing in data entry by scanning technology, the coverage generation are investigated. As a result, the deterioration of spatial resolution can be improved by using the histogram analysis and the line enhancement when we scan a map at a lower dpi. It is to be desired that a raster scanner dpi is selected 150 dpi or 200 dpi among five densities (75 dpi, 150, dpi, 200 dpi, 300 dpi, 400 dpi) in view of the storage of raster data and the RMSE of coverage generation. Also, it was very important role of the choice of trace parameters to trace raster data in the vectorizing procedure.

• Korean Journal of Child Studies
• /
• v.25 no.6
• /
• pp.171-189
• /
• 2004

Children develop emotional intelligence during the early years of life, and according to experts, emotional intelligence(EI) is a more reliable predictor of academic achievement than IQ. However, nowadays children appear to be low on emotional well-being. This has potentially negative consequences, not only for academic achievement but also for personal relationships. The purpose of this study was to develop emotional education program for young children(EEPYC). In this study, EI is defined to carry out reasoning in regard to emotions and to use emotion for enhancement of thought. Designed to facilitate development of young children's EI. EEPYC is based on the four branch model, which is mental EI model and based on the guiding principle of Collaborative to Advance Social and Emotional Learning. The subgroups(curricular) that compose EEPYC are Emotional Perception, appraisal, and expression, Self-recognition program, Self-esteem program, Emotional Stress Regulation, Emotional problem solving & conflict resolution. EEPYC has the potential of fostering emotional intelligence. Moreover, EEPYC can promote a motivation, prosocial activity, and regulation of stress. This helps young children to develope cognition and emotion in harmonious fashion.

• Journal of Sensor Science and Technology
• /
• v.24 no.6
• /
• pp.423-428
• /
• 2015

A bimetallic chip made of gold and silver was investigated in intensity interrogation mode to confirm enhancement of the SPR sensor resolution. Both reflectance curves of the bimetallic chip and the conventional gold chip was acquired and compared. The line width of the reflectance curve of the bimetallic chip was narrower than that of the conventional Au chip, resulting in steeper tangential slope. The reflectance was monitored at the angle related to the steepest tangential slope. The change in reflectance of the bimetallic chip was larger than that of the Au chip. The critical angle was analyzed by differentiating the reflectance with respect to incident angle twice. Acquiring the critical angle regarding to the sample informs the refractive index of the sample. Using various concentration of Bovine Serum Albumin, we confirmed that refractive index was linearly related to variation of reflectance of the bimetallic chip.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.10
• /
• pp.1853-1859
• /
• 2008

In this paper, we propose a novel method to improve the visual quality of reconstructed images for 3D pattern recognition based on the computational integral imaging reconstruction (CIIR). The proposed CIIR method provides improved 3D reconstructed images by superimposing magnified elemental images by a combination of a round mapping model and image interpolation algorithms. To objectively evaluate the proposed method, we introduce an experimental framework for a computational pickup process and a CIIR process using a Gaussian function and evaluate the proposed method. We also carry out experiments on 3D objects and present their results.

• Current Optics and Photonics
• /
• v.5 no.4
• /
• pp.351-361
• /
• 2021

Speckle imaging is capable of dynamic data acquisition at high spatiotemporal resolution, and has played a vital role in the functional study of biological specimens. The presence of various optical scatterers within the tissue causes alteration of speckle contrast. Thus structures like blood vessels can be delineated and quantified. Although laser speckle imaging is frequently used, an optimization process to ensure the maximum speckle contrast has not been available. In this respect, we here report an experimental procedure to optimize speckle contrast via applying different combinations of varying polarization of the illuminating laser light and multiple analyzer angles. Specifically, samples were illuminated by the p-polarization, 45°-polarization, and s-polarization of the incident laser, and speckle images were recorded without and with the analyzer rotated from 0° to 180° (Δ = 30°). Following the baseline imaging of a solid diffuser and a fixed brain sample, laser speckle contrast imaging (LSCI) was successfully performed to visualize in vivo mouse-brain blood flow. For oblique laser illumination, the maximum contrast achieved with p-polarized and s-polarized light was perpendicular to the analyzer's axis. This study demonstrates the optimization process for maximizing the speckle contrast, which can improve blood-flow estimation in vivo.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.30 no.3
• /
• pp.236-242
• /
• 2019

Ultra-wideband(UWB) is a technology that can transmit and receive signals at high speeds using a very short signal of wideband of several GHz, and has been recently used in the field of radar technology. Impulse radio(IR)-UWB radar is used in the field of motion recognition with high resolution. In this work, we studied motion recognition using IR-UWB radar. We constructed a development environment to acquire data about motion and implemented a signal processing algorithm for performance enhancement. Based on the signal processing result, the performance was verified through feature extraction and learning of motion.

• Korean Journal of Heritage: History & Science
• /
• v.36
• /
• pp.39-67
• /
• 2003

In this paper we examine cultural properties of the North Korea from 'the law of the Democratic People's Republic of Korea on Protection of Cultural Property". This law was adopted the Resolution of the Standing Committee of the Supreme People's Assembly of DPR of Korea in 1994. For our study, some other laws or rules established after the end of Japanese colonial occupation (1910-1945) in North Korea were examined. The policy on protection and conservation of cultural property in North Korea seems to have taken place a relatively rapid. The purpose of this law is to carry out the policy with a view to contributing to establishment of strict system and order for protection and management of cultural property, to their preservation in original state, to their proper inheritance and development, and to enhancement of national pride and confidence among the people. This law consists of 6 chapters (52 articles): (1) Fundamentals of the law on protection of cultural property, (2) Archaeological excavation and collection of cultural relics, (3) Evaluation and registration of cultural property, (4) Preservation and management of cultural property, (5) Restoration of cultural property, and (6) Guidance and control of cultural property protection. Nevertheless, it is difficult to find the evidence of efforts to exploit the cultural properties from an academic point of view in North Korea since the late 1980s.

• The Bulletin of The Korean Astronomical Society
• /
• v.44 no.1
• /
• pp.85.1-85.1
• /
• 2019

Accurate estimation of the masses, the ages, and the chemical abundances of host stars is crucial to understand physical characteristics of exo-planetary systems. In this study, we investigate physical dimensions of 94 planet-hosting stars based on spectroscopic observation and stellar evolutionary computation, From the high resolution echelle spectroscopy of the BOES observation, we have analysed metallicities and alpha-element enhancements of host stars. By combining recent spectro-photometric observations, stellar parameters are calibrated within the frame work of the standard stellar theory. In general, the minimum chi-square estimation can be strongly biased in cases that stellar properties rapidly changes after the terminal age main-sequence. Instead, we adopt a Bayesian statistics considering a priori distribution of stellar parameters during the rapid evolutionary phases. we determine a reliable set of stellar parameters between theoretical model grids. To overcome this statistical bias, (1) we adopt a Bayesian statistics considering a priori distribution of stellar parameters during the rapid evolutionary phases and (2) we construct the fine model grid that covers mass range ($0.2{\sim}3.0M_{\odot}$) with the mass step ${\Delta}M=0.01M_{\odot}$, metallicities Z = 0.0001 ~ 0.04, and the helium and the alpha-element enhancement. In this presentation, we introduce our calibration scheme for several hosting stars.