• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.4
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• pp.49-58
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• 2011

Typically, vision-based AR systems operate on the basis of prior knowledge of the environment such as a square marker. The traditional marker-based AR system has a limitation that the marker has to be located in the sensing range. Therefore, there have been considerable research efforts for the techniques known as real-time camera tracking, in which the system attempts to add unknown 3D features to its feature map, and these then provide registration even when the reference map is out of the sensing range. In this paper, we describe a real-time camera tracking framework specifically designed to track a monocular camera in a desktop workspace. Basic idea of the proposed scheme is that a real-time camera tracking is achieved on the basis of a plane tracking algorithm. Also we suggest a method for re-detecting features to maintain registration of virtual objects. The proposed method can cope with the problem that the features cannot be tracked, when they go out of the sensing range. The main advantage of the proposed system are not only low computational cost but also convenient. It can be applicable to an augmented reality system for mobile computing environment.

• Journal of the Korean Wood Science and Technology
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• v.38 no.6
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• pp.518-525
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• 2010

Infrared (IR) thermography which is the technique for detecting invisible infrared light emitted by objects due to their surface thermal condition and for producing an image of the light has been applied in various field without damaging the objects. It also could be used indirectly to examine the inside of an object. In this study, insulation property of wooden house in Korea Forest Research Institute (KFRI) was evaluated with according to "Thermal performance of building - Quantitative detection of thermal irregularities in building envelopes - infrared method (KS F 2829)". This method uses "Temperature Difference Ratio (TDR)" between outdoor wall surface and indoor wall surface of wooden building for evaluating its thermal performance. The thermal performance of a room on the 2nd floor of the wooden house was focused in this study and IR thermography on the indoor and outdoor surface of the house was captured by IR camera. Heat loss from the corner and the window of the wooden house as well as wall of the house was quantitatively evaluated and the invisible heat loss in the wall was detected. It is expected that the results from this study could contribute to improve the wooden building energy efficiency.

• YAKHAK HOEJI
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• v.57 no.2
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• pp.87-94
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• 2013

An analytical methodology based on solid-space extraction (SPE) with with Bond Elut Certify cartridge (Varian, 130 mg) has been developed for the qualification and quantitation of strychnine in blood. After the elution layer was evaporated, the residue was reconstituted with methanol for GC/MS. Internal standard was used 10 mg/l dextromethorphan. Strychnine is a potent central nervous stimulant and convulsant, and an alkaloid found in seeds of Strychnos nux-vomica. It was used therapeutically to improve circulation and muscle tone in oral or intramuscular doses of 0.05~8 mg. The fatal dose of strychnine for humans is 50~100 mg. A man was found dead lying curled up the corner of the large room in a roof house after the fire fighter opened a locked door inside to put out the fire. The postmortem blood and gastric contents were analyzed for toxicological testing. Strychnine and brucine were detected using GC/MS first in gastric contents extracts. The contents of strychnine was 0.083 mg/l in heart blood, 0.088 mg/l in peripheral blood and 4.0 mg/kg in gastric contents, respectively. Method validation was carried out in terms of linearity, accuracy, precision (intraday, interday) in blood. The assay is linear over 0.05~10 mg/l ($r^2$=0.999). Limit of detection (LOD) and limit of quantitation (LOQ) in blood were determined 0.02 mg/l (S/N=3) and 0.07 mg/l (S/N=10), respectively. Accuracy (bias%) of strychnine with 0.1, 1 and 10 mg/l was 12.0% (n=6), 9.3% (n=6) and 6.9% (n=6), respectively. Intraday precision (CV%) of strychnine with, 0.1, 1 and 10 mg/l were 6.4%, 10.4%, 1.2% (n=6), respectively. Interday precision (CV%) of strychnine with 0.1, 1 and 10 mg/l over three days were 24.0%, 18.5%, 13.8% (n=18), respectively. Relative recovery with 0.1, 1 and 10 mg/l (in blood) were 114.9%, 99.3% and 87.4% (n=6), respectively. The described method can be applied in forensic toxicology to determine strychnine in blood samples.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.5-9
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• 2004

In this paper, we studied the OCT(Optical Coherence Tomography) system which it has been extensively studied because of having some advantages such as high resolution cross-sectional images, low cost, and small size configuration. A basic principle of OCT system is Michelson interferometer. The characteristics of light source determine the resolution and the transmission depth. As a results, the light source have a commercial SLD with a central wavelength of 1,285 nm and FWHM(Full Width at Half Maximum) of 35.3 nm. The optical delay line part is necessary to equal of the optical path length with scattered light or reflected light from sample. In order to equal the optical path length, the stage which is attached to reference mirror is moved linearly by step motor And the interferometer is configured with the Michelson interferometer using single mod fiber, the scanner can be focused of the sample by using the reference arm. Also, the 2-dimensional cross-sectional images were measured with scanning the transverse direction of the sample by using step motor. After detecting the internal signal of lateral direction at a paint of sample, scanner is moved to obtain the cross-sectional image of 2-demensional by using step motor. Photodiode has been used which has high detection sensitivity, excellent noise characteristic, and dynamic range from 800 nm to 1,700 nm. It is detected mixed small signal between noise and interference signal with high frequency After filtering and amplifying this signal, only envelope curve of interference signal is detected. And then, cross-sectional image is shown through converting this signal into digitalized signal using A／D converter. The resolution of the OCT system is about 30$\mu\textrm{m}$ which corresponds to the theoretical resolution. Also, the cross-sectional image of ping-pong ball is measured. The OCT system is configured with Michelson interferometer which has a low contrast because of reducing the power of feedback interference light. Such a problem is overcomed by using the improved inteferometer. Also, in order to obtain the cross-sectional image within a short time, it is necessary to reduce the measurement time for improving the optical delay line.