• Journal of the Korean Vacuum Society
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• v.13 no.1
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• pp.1-8
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• 2004

The SOI wafer fabrication technique has been developed by using ion-cut process, based on proton implantation and wafer bonding techniques. It has been shown by TRIM simulation that 65 keV proton implantation is required for the standard SOI wafer (200 nm SOI, 400 nm BOX) fabrication. In order to investigate the optimum proton dose and primary annealing condition for wafer splitting, the surface morphologic change has been observed such as blistering and flaking. As a result, effective dose is found to be in the 6∼$9\times10^{16}$ $H^{+}/\textrm{cm}^2$ range, and the annealing at $550^{\circ}C$ for 30 minutes is expected to be optimum for wafer splitting. The depth distribution of implanted hydrogen has been experimentally confirmed by ERD and SIMS measurements. The microstructure evolution in the damaged layer was also studied by X-TEM analysis.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.2
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• pp.113-120
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• 2017

HCP(Half Cell Potential) method has been widely used since it is recognized as a efficient NDT(Non Destructive Technique) for corrosion detection. This work is for an evaluation of relation between corrosion amount and measured HCP in dried condition through ICM(Impressed Current Method) for accelerating corrosion. For the work, cement mortar specimens with three w/c ratios and four cover depths are prepared, and corrosion test based on ICM is performed for 6 hours, 18 hour, and 42 hours with constant 20V of electrical charge, respectively. From the test, corrosion amount increases with reduced cover depth, increasing w/c ratio, and extended corrosion period, where corrosion amount is evaluated to linearly increases with measured HCP in dried condition. In order to evaluate corrosion amount through measured HCP, the measured HCP level is firstly determined and then corrosion amount is to be compared with measured HCP, which is evaluated to be more reasonable with higher C.O.V.

• Journal of the Korean Chemical Society
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• v.43 no.2
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• pp.182-192
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• 1999

The new GD/ICP-AES quick change over system has been developed and characterized. Within less than 15 minutes, ICP-AES could be switched to GD-AES and vise a versa. As a result, both solid and liquid samples could be analyzed in a very short period of time by the ICP/GD-AES quick change over system developed in our laboratory. The influences of the experimental variables, such as flow rate of coolant gas, flow rate of auxiliary gas, flow rate of sample carrier gas, sampling depth, orifice size of sampling cone, and rf (radio frequency) power on emission intensity have been presented. The detection limits of Cd(I) 228.8 nm, Mn (II) 257.61 nm, and Fe(II) 259.95 nm were found to be 3.86, 1.49, and 5.79 ppb, respectively. And linealities of the calibration curves were measured to be unity.

• The KIPS Transactions:PartB
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• v.9B no.3
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• pp.327-336
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• 2002

Texture analysis is an important technique in many image understanding areas, such as perception of surface, object, shape and depth. But the previous works are intend to the issue of only texture segment, that is not capable of acquiring recognition information. No unsupervised method is basased on the recognition of texture in image. we propose a novel approach for efficient texture image analysis that uses unsupervised learning schemes for the texture recognition. The self-organization neural network for multiple texture image identification is based on block-based clustering and merging. The texture features used are the angle and magnitude in orientation-field that might be different from the sample textures. In order to show the performance of the proposed system, After we have attempted to build a various texture images. The final segmentation is achieved by using efficient edge detection algorithm applying to block-based dilation. The experimental results show that the performance of the system Is very successful.

• Journal of Biomedical Engineering Research
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• v.28 no.1
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• pp.84-94
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• 2007

In order to collect information on local distribution of conductivity and permittivity underneath a scan probe, we developed a multi-frequency trans-admittance scanner (TAS). Applying a sinusoidal voltage with variable frequency on a chosen distal part of a human body, we measure exit currents from 320 grounded electrodes placed on a chosen surface of the subject. The electrodes are packaged inside a small and light scan probe. The system includes one voltage source and 17 digital ammeters. Front-end of each ammeter is a current-to-voltage converter with virtual grounding of a chosen electrode. The rest of the ammeter is a voltmeter performing digital phase-sensitive demodulation. Using resistor loads, we calibrate the system including the scan probe to compensate frequency-dependent variability of current measurements and also inter-channel variability among multiple. We found that SNR of each ammeter is about 85dB and the minimal measurable current is 5nA. Using saline phantoms with objects made from TX-151, we verified the performance of the lesion estimation algorithm. The error rate of the depth estimation was about 19.7%. For the size estimate, the error rate was about 15.3%. The results suggest improvement in lesion estimation algorithm based on multi-frequency trans-admittance data.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.45 no.3
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• pp.151-156
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• 2009

This study shows that the distribution density of snow crab, Chionoecetes opilio, was estimated using an underwater video monitoring system attached on the towing sledge. The field experiments were carried out at the coastal waters around Chuksan, East Sea, where ranged from 110 to 130m depth during September and October 2007. The sledge was towed for 40 minutes and the towing speed was controlled between 1.5 to 1.7 knot and each research areas were calculated to multiply towed distance by the detection width of the video monitoring system(1.2m), and then, distribution density of snow crab in each observations were estimated as a counted number of crab per 1,000$m^2$. The result shows that their survey, taken between two months, reflected similar results during survey period, and the maximum and mean distribution densities in September estimated to be 77.0(number/1,000$m^2$) and 19.9, respectively, and those of October were 36.0 and 21.8, respectively.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.1
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• pp.341-363
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• 2016

Haze or fog is a common natural phenomenon. In foggy weather, the captured pictures are difficult to be applied to computer vision system, such as road traffic detection, target tracking, etc. Therefore, the image dehazing technique has become a hotspot in the field of image processing. This paper presents an overview of the existing achievements on the image dehazing technique. The intent of this paper is not to review all the relevant works that have appeared in the literature, but rather to focus on two main works, that is, image dehazing scheme based on atmospheric veil and image dehazing scheme based on dark channel prior. After the overview and a comparative study, we propose an improved image dehazing method, which is based on two image dehazing schemes mentioned above. Our image dehazing method can obtain the fog-free images by proposing a more desirable atmospheric veil and estimating atmospheric light more accurately. In addition, we adjust the transmission of the sky regions and conduct tone mapping for the obtained images. Compared with other state of the art algorithms, experiment results show that images recovered by our algorithm are clearer and more natural, especially at distant scene and places where scene depth jumps abruptly.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.11B
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• pp.1403-1412
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• 2011

This study performed a detecting research of promising R&D field utilizing intuitive methodology regarding OLED illumination industry. For this, 69 professionals of the illumination industry in Korea were composed as a panel to hold an in-depth interview and survey for 1 month. The study classified the OLED illumination industry as 4 fields of panel, material/component for panel, manufacturing equipment, and lighting system, and selected core technology for each field, and divided it into a total of 14 possible fields for R&D. As a result of evaluating the technological competitive power for each field, the field in Korea which received the highest technological competitive power was OLED panel, and contrarily, technological competitive power of material/component for OLED panel showed the lowest, which requires improvement Meanwhile, evaluating economical aspect, conformity to policy, and effectiveness of R&D in general, 7 promising R&D fields were selected. The 4 core technologies of OLED panel, which are, white, transparent, color change and flexible OLED manufacturing technology were evaluated as the most promising fields, and next, organic material for surface light source, material/component for substrate and equipment for forming large sized substrate were evaluated as promising fields.

• Geophysics and Geophysical Exploration
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• v.16 no.4
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• pp.234-239
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• 2013

The $M_W$ 9.0 thrust-fault earthquake has occurred in the Pacific coast of Tohoku, Japan, on March 11, 2011. We present the detection of the great earthquake and analyze T-waves associated with the main event and two other big aftershocks ($M_W$ > 7) recorded in a hydroacoustic array (H11N) in the Pacific Ocean by performing array and spectral analysis to examine characteristics of T-waves generated from the big events. The complex rupture process of the main event directly influences on the shape of the T-waves, and the peak locates on where T-waves excited from fast rupturing process arrive. We compare the two aftershocks with different fault type and show that the fault type and the source depth change shape and spectral contents of T-waves.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2036-2041
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• 2005

The underwater multi-agent technology has many potential for the various activities related to ocean development/conservation in the near future. For example, in such fields as water pollution investigation, aquaculture control, or coral reef research, we feel a growing need for a system that realizes underwater continuous monitoring in the wide rang e. In this case, the target monitoring area will be sliced planar hierarchically toward the depth as monitoring layers, and many AUVs arranged on each layer track the given trajectory and gather various environmental information continuously, with communicating each other in the layer or with other layers. To realize those systems we need to develop AUV multi-agent technologies. So we are now building basic systems for basin experiment for the development of AUV multi-agent behavior. We must experience many situations and problems to be solved for the development of its elemental technologies by using real systems as well as our computer simulations. In this paper we introduce our concept of the experiment in the near future and the hardware/software design of our two types of handy AUVs and ultrasound ranging/communication system for that experiment. One AUV is designed using a 17inches-diameter glass sphere with DOS/V and RT-Linux based subsystems, which is intended to use not only in the basin but also in the calm real sea. The other AUV is designed for the basin experiment using a 7inches-diameter acrylic sphere with low-cost embedded system with SH-2 based subsystems. The basin experiment to verify the basic AUV facilities and ultrasound ranging for position detection was carried out.