• Title/Summary/Keyword: CCD

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Vehicle Detection using Feature Points with Directional Features (방향성 특징을 가지는 특징 점에 의한 차량 검출)

  • Choi Dong-Hyuk;Kim Byoung-Soo
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.42 no.2 s.302
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    • pp.11-18
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    • 2005
  • To detect vehicles in image, first the image is transformed with the steerable pyramid which has independent directions and levels. Feature vectors are the collection of filter responses at different scales of a steerable image pyramid. For the detection of vehicles in image, feature vectors in feature points of the vehicle image is used. First the feature points are selected with the grid points in vehicle image that are evenly spaced, and second, the feature points are comer points which m selected by human, and last the feature points are corner Points which are selected in grid points. Next the feature vectors of the model vehicle image we compared the patch of the test images, and if the distance of the model and the patch of the test images is lower than the predefined threshold, the input patch is decided to a vehicle. In experiment, the total 11,191 vehicle images are captured at day(10,576) and night(624) in the two local roads. And the $92.0\%$ at day and $87.3\%$ at night detection rate is achieved.

Micro-crack Detection in Polycrystalline Solar Cells using Improved Anisotropic Diffusion Model (개선된 비등방 확산 모델을 이용한 다결정형 솔라셀의 마이크로 크랙 검출)

  • Ko, JinSeok;Rheem, JaeYeol
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.183-190
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    • 2013
  • In this paper, we propose an improved anisotropic diffusion model for micro-crack detection in heterogeneously textured surface of polycrystalline solar wafers. Due to the nature of the image sensor, the gray-level of the diagonal micro-crack is non-uniform. Thus, the conventional algorithms can't fully detect diagonal micro-cracks when the number of iteration is not enough. However, the increasing of the iteration number leads to increase computation time and detects micro-crack thicker than the original micro-crack. In order to overcome this drawback, we use the gradient of north, south, east, and west directions as well as extended directions. To calculate the diffusion coefficients, we compare the gradients of conventional directions and extended directions and apply the larger gradient values to the coefficient function. This is because the proposed method reflects the information of diagonal micro-crack. Comparing to Tsai et al.'s and Ko and Rheem's, the proposed algorithm shows superior efficiency in detecting the diagonal micro-cracks with less iterations in the images of polycrystalline solar wafers. In addition, it also shows that the thickness of segmented micro-crack is similar to the orignal micro-crack.

Technique for the Measurement of Crack Widths at Notched / Unnotched Regions and Local Strains (콘크리트의 노치 및 비노치 구역에서의 균열폭 및 국부 변형률 정밀 측정기법)

  • Choi, Sok-Hwan;Lim, Bub-Mook;Oh, Chang-Kook;Joh, Chang-Bin
    • Journal of the Korea Concrete Institute
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    • v.24 no.2
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    • pp.205-214
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    • 2012
  • Crack widths play an important role in the serviceability limit state. When crack widths are controlled sufficiently, the reinforcement corrosion can be reduced using only existing concrete cover thickness due to low permeability in the region of finely distributed hair-cracks. Thus, the knowledge about the tensile crack opening is essential in designing more durable concrete structures. Therefore, numerous researches related to the topic have been performed. Nevertheless accurate measurement of a crack width is not a simple task due to several reasons such as unknown potential crack formation location and crack opening damaging strain gages. In order to overcome these difficulties and measure precise crack widths, a displacement measurement system was developed using digital image correlation. Accuracy calibration tests gave an average measurement error of 0.069 pixels and a standard deviation of 0.050 pixels. Direct tensile test was performed using ultra high performance concrete specimens. Crack widths at both notched and unnotched locations were measured and compared with clip-in gages at various loading steps to obtain crack opening profile. Tensile deformation characteristics of concrete were well visualized using displacement vectors and full-field displacement contour maps. The proposed technique made it possible to measure crack widths at arbitrary locations, which is difficult with conventional gages such as clip-in gages or displacement transducers.

Fiber Classification and Detection Technique Proposed for Applying on the PVA-ECC Sectional Image (PVA-ECC단면 이미지의 섬유 분류 및 검출 기법)

  • Kim, Yun-Yong;Lee, Bang-Yeon;Kim, Jin-Keun
    • Journal of the Korea Concrete Institute
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    • v.20 no.4
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    • pp.513-522
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    • 2008
  • The fiber dispersion performance in fiber-reinforced cementitious composites is a crucial factor with respect to achieving desired mechanical performance. However, evaluation of the fiber dispersion performance in the composite PVA-ECC (Polyvinyl alcohol-Engineered Cementitious Composite) is extremely challenging because of the low contrast of PVA fibers with the cement-based matrix. In the present work, an enhanced fiber detection technique is developed and demonstrated. Using a fluorescence technique on the PVA-ECC, PVA fibers are observed as green dots in the cross-section of the composite. After capturing the fluorescence image with a Charged Couple Device (CCD) camera through a microscope. The fibers are more accurately detected by employing a series of process based on a categorization, watershed segmentation, and morphological reconstruction.

Comparison of Anti-Inflammatory Activity of Spirulina maxima Extract by Ultrasonication and Water Extraction Process (Spirulina maxima의 초음파 및 열수 추출 공정에 따른 항염증 효과 비교 탐색)

  • Sin, Jae Bin;Choi, Woon Yong;Kang, Do Hyung;Lee, Hyeon Yong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.12
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    • pp.1852-1857
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    • 2014
  • The aim of this study was to compare the anti-inflammatory activities of Spirulina maxima treated with ultrasonication and water extraction process. S. maxima extracted via ultrasonication showed low cytotoxicity (16.90%) in a normal human cell line, CCD-986sk. Especially, S. maxima ultrasonication extract showed the highest DPPH radical scavenging activities (46.82%) compared to water extract (31.30%) at $100^{\circ}C$. In addition, ultrasonication extract showed a high amount of flavonoids (21.60 mg/g) and total phenols ($8.36{\mu}g/mL$). Nitric oxide production by 1.0 mg/mL of S. maxima ultrasonication extract strongly inhibited ($1.3770{\mu}M$), whereas water extract showed lower inhibition ($1.5784{\mu}M$). TNF-${\alpha}$ and IL-6 cytokines were effectively inhibited by 1.0 mg/mL of S. maxima ultrasonication extract, which shows strong antioxidant activities. Based on these results, it can be concluded that the ultrasonication process increase anti-inflammatory activity of S. maxima extract.

DISK OF Be STAR WITH EMISSION (Hα 방출선을 통한 Be 항성 원반)

  • Ahn, Dae-Gun;Bae, Jang-Ho;Lee, Sang-Gak;Shin, Young-Woo;Ko, Yeon-Gyung;Kang, Suk-Chul
    • Publications of The Korean Astronomical Society
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    • v.22 no.4
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    • pp.133-140
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    • 2007
  • We have determined the disk size of Be stars by using $H{\alpha}$ emission. We observed spectra of Be stars with telescope in SNU, equipped with SB SGS (Santa Babara Self Guided Spectrograph) and CCD ST-8. The size of disk of Be stars was estimated with the Be star model of Grundstrom & Gies (2006). This study suggests that the medium resolution spectra taken with small telescope equipped with commercial spectrograph are useful to estimate the approximate size of the $H{\alpha}$ emitting disk around Be stars.

A Study on the Method of High-Speed Reading of Postal 4-state Bar Code for Supporting Automatic Processing (우편용 4-state 바코드 고속판독 방법에 관한 연구)

  • Park, Moon-Sung;Kim, Hye-Kyu;Jung, Hoe-Kyung
    • The KIPS Transactions:PartD
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    • v.8D no.3
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    • pp.285-294
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    • 2001
  • Recently many efforts on the development of automatic processing system for delivery sequency sorting have been performed in ETRI, which requires the use of postal 4-state bar code system to encode delivery points. This paper addresses the issue on the extension of read range and the improvement of image processing method. For the improvement of image processing procedure, applied information acquisition method through basic two thresholds onto the horizontal axial line of gray image based on reference information of 4-state bar code symbology. Symbol values are computed after creating two threshold values based on the obtained information through search of horizontal axial values. The implementation result of 4-state bar code reader are obtained the symbol values within 30~60 msec (58,000~116,000 mail item/hour)without noise removal or image rotation in spite of the incline $\pm 45^{\circ}$.

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Development of Automatic Sorting System for Black Plastics Using Laser Induced Breakdown Spectroscopy (LIBS) (LIBS를 이용한 흑색 플라스틱의 자동선별 시스템 개발)

  • Park, Eun Kyu;Jung, Bam Bit;Choi, Woo Zin;Oh, Sung Kwun
    • Resources Recycling
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    • v.26 no.6
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    • pp.73-83
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    • 2017
  • Used small household appliances have a wide variety of product types and component materials, and contain high percentage of black plastics. However, they are not being recycled efficiently as conventional sensors such as near-infrared ray (NIR), etc. are not able to detect black plastic by types. In the present study, an automatic sorting system was developed based on laser-induced breakdown spectroscopy (LIBS) to promote the recycling of waste plastics. The system we developed mainly consists of sample feeder, automatic position recognition system, LIBS device, separator and control unit. By applying laser pulse on the target sample, characteristic spectral data can be obtained and analyzed by using CCD detectors. The obtained data was then treated by using a classifier, which was developed based on artificial intelligent algorithm. The separation tests on waste plastics also were carried out by using a lab-scale automatic sorting system and the test results will be discussed. The classification rate of the radial basis neural network (RBFNNs) classifier developed in this study was about > 97%. The recognition rate of the black plastic by types with the automatic sorting system was more than 94.0% and the sorting efficiency was more than 80.0%. Automatic sorting system based on LIBS technology is in its infant stage and it has a high potential for utilization in and outside Korea due to its excellent economic efficiency.

An Image Management System of Frame Unit on a Hand-held Device Environments (휴대장치 환경을 위한 프레임 단위의 영상 데이터 관리 시스템)

  • Choi, Jun-Hyeog;Yoon, Kyung-Bae;Han, Seung-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.7
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    • pp.29-36
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    • 2008
  • This paper proposes algorithm for the system that can search for an image of a frame unit, and we implement it. A system already inserts in images after generating the cord that mechanical decoding and identification are possible. We are independent of an external noise in a frame unit, and a system to propose at these papers can search for an image recorded by search condition to include recording date, recording time, a recording place or filming course etc. This system is composed by image insertion wealth to insert data to an image to data image code generation wealth, a frame generating data image code you apply a code generation rule to be fixed in order to express to a price to have continued like data entry wealth, GPS locator values and direction price receiving an image signal, image decoding signals and an image search signal to include search condition, and to have continuity from users each of an image. Also, image decoding we decipher about the noise that was already added from the outsides in a telerecording process, a copy process or storage processes inserted in images by real time, and searching image information by search condition. Consequently we implement decoder, and provide the early system that you use, and we easily insert data code among images. and we can search. and maximization can get precision regarding an image search and use satisfaction as we use algorithm to propose at these papers.

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Optimization of the re-extraction process of ethanol from catechin components from Korean green tea extract (한국산 녹차추출물 catechin 성분의 ethanol 재추출 공정 최적화)

  • Jo, In-Hee;Kim, Myung-Kyoo;Jang, Suh-Yoon;Kim, Na-Ra;Lee, Won-Young
    • Food Science and Preservation
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    • v.23 no.5
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    • pp.696-703
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    • 2016
  • The purpose of this study was to determine the optimum re-extraction conditions of ethanol from catechin in Korean green tea (Camellia sinensis L.) using response surface methodology (RSM). The experiments were carried out according to a five level and two variable central composite design (CCD). The two independent variables were solvent ratio to sample content (1, 4, 7, 10, 13 mL/g) and extraction temperature (-20, -10, 0, 10, $20^{\circ}C$) on the dependent variables including yield, epigallocatechin (EGC), epicathchin (EC), epigallocatechingallate (EGCG), epicatechingallate (ECG), total catechin and caffeine. ANOVA results showed that Coefficients of determination ($R^2$) of estimated models for dependent variables were ranged from 0.9054~0.9778, while $R^2$ of caffeine were estimated 0.8770. The optimum ranges for the maximized extraction including yield, EGC, EC, EGCG, ECG, caffeine and total catechin were 4.5~7.5 mL/g in ratio of ethanol to sample and $-8{\sim}8^{\circ}C$ in extraction temperature. The actual values of yield, EGC, EC, EGCG, ECG, caffeine and total catechin, respectively, at the optimized conditions were 35.02%, 13.31%, 3.978%, 19.11%, 4.29%, 5.30% and 40.68%.