• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.49.3-49.3
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• 2018

가시광 CCD나 HxRG 등의 적외선 어레이 디텍터는 천문관측기기를 구성하는 핵심부품으로, 관측기기의 종합 성능 결정에 중요한 영향을 미친다. 따라서 디텍터의 성능을 정확하게 진단하는 것은 관측기기의 성능을 예측하거나 유지 또는 개선하는데 중요한 요소가 된다. 한국천문연구원은 최근에 디텍터 성능을 직접적으로 측정할 수 있는 광전자 시스템을 구축하고 장치를 구동하기 위한 소프트웨어를 자체 개발하였다. 본 시스템을 기반으로 Andor iKon-M 카메라 CCD의 시스템 게인, 최대 포화전자수, 감도, 비선형성, 양자효율, 암전류, 읽기 잡음, 불량 픽셀의 특성을 측정하였으며 특히, 양자효율의 경우 디텍터의 구동 온도에 따라 파장별로 2%에서 30% 이상까지 편차가 발생하는 것을 확인하였다. 본 연구는 디텍터의 성능 평가와 그 중요성에 대하여 논의한다.

• Structural Engineering and Mechanics
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• v.55 no.2
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• pp.263-280
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• 2015

This paper describes a study of the collision of hard steel spheres against aluminium thin circular plates at speeds up to 140 m/s. The tests were monitored by a high speed camera and a chronoscope, which allowed the determination of the ballistic limit and the plate deformation pattern. Quasi-static material parameters were obtained from tests on a universal testing machine and dynamic mechanical characterization of two aluminium alloys were conducted in a split Hopkinson pressure bar. Using a damage model, the perforation of the plates was simulated by finite element analysis. Axisymmetric, shell and solid elements were employed with various parameters of the numerical analysis being thoroughly discussed, in special, the dynamic model parameters. A good agreement between experiments and the numerical analysis was obtained.

• Journal of the Korean Ceramic Society
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• v.28 no.3
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• pp.234-242
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• 1991

Ti-B system ceramics were prepared by the self-propagating high-temperature synthesis method from the mixture of metal titanium and boron powders The major crystalline phase as a function of boron content was TiB for mixtures containing 0.5 or 1.0mol B, and TiB2 for these containing over 1.3mol B. The combustion mode observed by a high-speed camera was steady-state. The Combustion velocity increased with increasing the boron content. Sintered TiB2 specimen showed the density of 97% of theoretical valve, Vicker's hardness of 2250kg/㎟ for 0.2kg load and three-point-flexure strength of 500MPa.

• Journal of Korea Multimedia Society
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• v.14 no.7
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• pp.858-865
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• 2011

In order to allow the user to efficiently browse, select, and retrieve a desired video part without having to deal directly with GBytes of compressed data, classification of shot motion characteristic has to be carried out as a preparation for such user interaction. The organization of video information for video database requires segmentation of a video into its constituent shots and their subsequent characterization in terms of content and camera movement in shot. In order to classify shot motion, it is a conventional way to use element of motion vector. However, there is a limit to estimate global camera motion because the way that uses motion vectors only represents local movement. For shot classification in terms of motion information, we propose a new scheme consisting of partial decoding of INTRA pictures and comparing the x, y displacement vector curve between the decoded I-frame and next P-frame in compressed video data.

• Biomedical Science Letters
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• v.21 no.1
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• pp.23-31
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• 2015

Recently, specific antibodies have been used extensively to diagnose and treat various diseases. It is essential to assess the efficacy and specificity of antibodies, especially the in vivo environment. Anti-HER-2/neu mAb was evaluated as a possible transporting agent for radioimmunotherapy. The monoclonal antibody was successfully radio-labeled with $^{131}I$. In vitro binding assays were performed to confirm its targeting ability using another radio-iodine, $^{125}I$. Binding percentage of $^{125}I$ labeled anti-HER-2/neu mAb in HER-2/neu expressing CT-26 cells was found to be 4.5%, whereas the binding percentage of $^{125}I$ labeled anti-HER-2/neu mAb in wild-type CT-26 was only 0.45%. In vivo images were obtained and analyzed through $\gamma$-camera and an optical fluorescent modality, IVIS-200. $\gamma$-camera images showed that $^{131}I$ labeled anti-HER-2/neu mAb accumulated in HER-2/neu CT-26 tumors. Optical imaging based on near infrared fluorescence labeled anti-HER-2/neu mAb showed higher fluorescence intensities in HER-2/neu CT-26 tumors than in wild-type CT-26 tumors. Anti-HER-2/neu mAb was found to specifically bind to its receptor expressing tumor. Our study demonstrates that in vivo imaging technique is a useful method for the evaluation of an antibody's therapeutic and diagnostic potentials.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.3
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• pp.847-852
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• 2010

Text in natural images has a various and important feature of image. Therefore, to detect text and extraction of text, recognizing it is a studied as an important research area. Lately, many applications of various fields is being developed based on mobile phone camera technology. Detecting edge component form gray-scale image and detect an boundary of text regions by local standard deviation and get an connected components using Euclidean distance of RGB color space. Labeling the detected edges and connected component and get bounding boxes each regions. Candidate of text achieved with heuristic rule of text. Detected candidate text regions was merged for generation for one candidate text region, then text region detected with verifying candidate text region using ectilarity characterization of adjacency and ectilarity between candidate text regions. Experctental results, We improved text region detection rate using completentary of edge and color connected component.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.171-179
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• 2005

It is essential to understand the role of wall lining materials when they are exposed to a fire from an ignition source. Full-scale test methods permit an assessment of the performance of a wall lining material. Fire growth models have been developed due to the costly expense associated with full-scale testing. The models require heat flux maps from the ignition burner flame as input data. Work to date was impeded by a lack of detailed spatial characterization of the heat flux maps due to the use of limited instrumentation. To increase the power of fire modeling, accurate and detailed heat flux maps from the ignition burner are essential. High level spatial resolution for surface temperature can be provided from an infrared camera. The objective of this study was to develop a heat flux mapping procedure for a room test burner flame to a wall configuration with surface temperature information taken from an infrared camera. A prototype experiment was performed using the ISO 9705 test burner to demonstrate the developed heat flux mapping procedure. The results of the experiment allow the heat flux and spatial resolutions of the method to be determined and compared to the methods currently available.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.12C
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• pp.1200-1208
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• 2003

Affective computing plays an important role in intelligent Human Computer Interactions(HCI). To detect emotional events, it is desirable to construct a computing model for extracting emotion related features from video. In this paper, we propose a statistical model based on the probabilistic distribution of low level features in video shots. The proposed method extracts low level features from video shots and then from a GMM(Gaussian Mixture Model) for them to detect emotional shots. As low level features, we use color, camera motion and sequence of shot lengths. The features can be modeled as a GMM by using EM(Expectation Maximization) algorithm and the relations between time and emotions are estimated by MLE(Maximum Likelihood Estimation). Finally, the two statistical models are combined together using Bayesian framework to detect emotional events in video.

• Journal of Computational Design and Engineering
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• v.1 no.3
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• pp.194-201
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• 2014

Optimization of design is an important step in obtaining tissue engineering scaffolds with appropriate shapes and inner micro-structures. Different shapes and sizes of scaffolds are modeled using UGS NX 6.0 software with variable pore sizes. The quality issue we are concerned is the scaffold porosity, which is mainly caused by the fabrication inaccuracies. Bone scaffolds are usually characterized using a scanning electron microscope, but this study presents a new automated inspection and classification technique. Due to many numbers and size variations for the pores, the manual inspection of the fabricated scaffolds tends to be error-prone and costly. Manual inspection also raises the chance of contamination. Thus, non-contact, precise inspection is preferred. In this study, the critical dimensions are automatically measured by the vision camera. The measured data are analyzed to classify the quality characteristics. The automated inspection and classification techniques developed in this study are expected to improve the quality of the fabricated scaffolds and reduce the overall cost of manufacturing.

• Journal of the Korean Ceramic Society
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• v.31 no.3
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• pp.265-274
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• 1994

Intermetallic Ti-Si system ceramics were synthesized from stochiometric mixtures of titanium and silicone powders in vacuum by Self-propagating High-temperature Synthesis(SHS). In each cases of Ti5Si3, Ti5Si4 and TiSi, and TiSi2 synthesis, 20wt% product dilution, direct ignition and SHS chemical furnace method were employed. The combustion modes, which were observed during the synthesis process by using the high speed camera, of Ti5Si3, Ti5Si4, TiSi, and TiSi2 exhibit spin, osciallatory, steady-state, and spin combustion, respectively. With increasing Ti/Si molar ratio an decrease of combustion velocities was found. From the results on the measurement of the flexural strength, the specimen hot pressed at 135$0^{\circ}C$ for 30 min using synthesized Ti5Si4 powders showed the highest flexural strength at 215 MPa.