• 방송공학회논문지
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• 제7권2호
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• pp.168-180
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• 2002

This paper proposes a novel method to detect unauthorized copies of digital images. This copy detection scheme can be used as either an alternative approach or a complementary approach to watermarking. A test image is reduced to 8$\times$8 sub-image by intensity averaging, and the AC coefficients of its discrete cosine transform (DCT) are used to compute distance from those generated from the query image, of which a user wants to find copies. Copies may be Processed to avoid copy detection or enhance image quality. We show ordinal measure of DCT coefficients, which is based on relative ordering of AC magnitude values and using distance metrics between two rank permutations, are robust to various modifications of the original image. The optimal threshold selection scheme using the maximum a posteriori (MAP) criterion is also addressed.

• 한국생산제조학회지
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• 제21권4호
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• pp.541-546
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• 2012

This study investigates the detection system of oil pollution level using single optical fiber sensor. This study focus on sensing of oil pollution by moisture and iron powder which are representatives of oil pollution factor. In addition, It is placed that the water and iron powder as an oil pollution factor in the oil tank which is the oil circulation in. The oil pollution detection system was measured by the changing of intensity of light and sensing gap. The result of this experimentation not only confirmed the contamination by moisture volume in the oil tank from the section 190ppm to 540ppm, but also monitored the contamination by iron volume from the section 1200ppm to 3500ppm. This study confirmed effectiveness of this detection system using optical fiber sensor. There is expectations of measuring another section by various optical fiber sensor.

• Mass Spectrometry Letters
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• 제8권1호
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• pp.14-17
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• 2017

The effect of cationization agent concentration on glycan detection via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was investigated using $Na^+$ ions in the form of NaCl as the cationization agent. NaCl solution concentrations ranging from 1 mM to 1 M were investigated. Glycans from ovalbumin were mixed with the cationization agent solution and the 2,5-dihydroxybenzoic acid (2,5-DHB) matrix solution in a volume ratio of 1:1:1. The resulting mixture was loaded onto the MALDI plate. Two MALDI-TOF MS instruments (Voyager DE-STR MALDI-TOF MS and Tinkerbell RT MALDI-TOF MS) were used for detection of glycans. The best detection, in terms of the number of identified glycans, the peak intensity, and the signal-to-noise (S/N) ratio, was obtained with NaCl concentrations of 0.01-0.1 M for both MALDI-TOF MS instruments.

• 한국자동차공학회논문집
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• 제7권6호
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• pp.42-48
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• 1999

Engine misfire causes of the negative effect on exhaust emission such as HC, CO, and NOX . Moreover, it causes damage to the three-way-catalyst(TWC) system permanently. The crankshaft velocity fluctuation(CVF) method has been applied for the real cars as misfire detection system usually, which utilizes the crank angle sensor input to calculate the variation of the crankshaft rotational speed. But this approach has the limit due to the fact that three could be problem under certain engine condition like as deceleration or high speed condition . Therefore the development of new methods are requested today. This study introduced the new method of misfire detection using breakdown voltage(BDV) characteristics between spark plug electrouds.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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• pp.86-93
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• 2017

In this paper, we propose a novel defect detection method using component tree representations of scanning electron microscopy (SEM) images. The component tree contains rich information about the topological structure of images such as the stiffness of intensity changes, area, and volume of the lobes. This information can be used effectively in detecting suspicious defect areas. A quasi-linear algorithm is available for constructing the component tree and computing these attributes. In this paper, we modify the original component tree algorithm to be suitable for our defect detection application. First, we exclude pixels that are near the ground level during the initial stage of component tree construction. Next, we detect significant lobes based on multiple attributes and edge information. Our experiments performed with actual SEM wafer images show promising results. For a $1000{\times}1000$ image, the proposed algorithm performed the whole process in 1.36 seconds.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1334-1336
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• 2001

In this study, laser ablation atomic fluorescence (LAAF) spectroscopy has been applied for a nanometer-scale surface analysis of Na-doped polymethyl methacrylate (PMMA). LAAF spectroscopy is a new sensitive element detection technique which involves atomizing of a sample by the laser ablation and detection of ablated plume by laser-induced fluorescence (LIF) spectroscopy. Using this technique in the detection of Na atoms with Na-doped PMMA, a detection limit is obtained as 36 fg for single laser shot. Further, the depth distribution in the sample is measured with a very high spatial resolution using a two-layer PMMA sample by observing the shot-by-shot LIF intensity from the Na atoms.

• 센서학회지
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• 제20권6호
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• pp.388-392
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• 2011

In this paper, a face detection method for interactive TV control system using a new feature, edge histogram feature, with a support vector machine(SVM) in the near-infrared(NIR) images is proposed. The edge histogram feature is extracted using 16-directional edge intensity and a histogram. Compared to the previous method using local binary pattern(LBP) feature, the proposed method using edge histogram feature has better performance in both smaller feature size and lower equal error rate(EER) for face detection experiments in NIR databases.

• Journal of Multimedia Information System
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• 제4권2호
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• pp.79-82
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• 2017

Smoke and fire have different shapes and colours. This article suggests a fully connected system which is used two features using Adaboost algorithm for constructing a strong classifier as linear combination. We calculate the local histogram feature by gradient and bin, local binary pattern value, and projection vectors for each cell. According to the histogram magnitude, this paper applied adapted weighting value to improve the recognition rate. To preserve the local region and shape feature which has edge intensity, this paper processed the normalization sequence. For the extracted features, this paper Adaboost algorithm which makes strong classification to classify the objects. Our smoke detection system based on the proposed approach leads to higher detection accuracy than other system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(4)
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• pp.215-218
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• 2002

The edges of an image hold much of the information in that image. The edges tell where objects are, their shape and size, and something about their texture. An edge is where the intensity of an image moves from a low value to a high value. We introduce the edge detection using the differential operator with Sobel operator and describe a nonparametric Wilcoxon test based on statistical hypothesis testing for the detection of edges. This paper proposes an efficient edge detection using Van der Waerden's statistic in original and noisy images. We use the threshold determined by specifying significance level a and an edge-height parameter. Comparison with our statistical test and Sobel operator shows that Van der Waerden method perform more effectively in both noisy and noise-free images.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 B
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• pp.883-885
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• 1995

Edges are one of the most important features used in various computer vision applications. Most of the known edge detection techniques are categorized into three gropus: First two approaches are to find gray level changes using first-order or second-order differentiation. The third method uses intrinsic propoeties of edges such as the result shown during scale space filtering. In this paper, we study various kind of edge detection techniques. Two images (Lenna image and a certain image which is composed of step, ramp, roof, and other artificial edge patterns) are used to compare different edge detection techniques and to verify the advantages and disadvantage of each techniques.