• Title/Summary/Keyword: overlap method

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Limitations of time resolution and spatial overlap caused by group velocity mismatch in experiments using ultrashort UV and visible optical pulses. (자외선과 가시광선 극초단 펄스 실험의 군속도 차이에 의한 시간 분해능 및 공간 겹침의 제한)

  • 김성규
    • Korean Journal of Optics and Photonics
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    • v.5 no.2
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    • pp.252-259
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    • 1994
  • The method of calculating overlap dispersion caused by group velocity mismatch between uv and visible pulses in ultrafast pump-probe experiments is presented to discuss limitations of the time resolution and signal intensity. The calculations show arrangements using a single focusing lens shall result in undesirable time resolution and low signal intensity. Achromatic doublets result in unrealistic solutions. However, dramatic improvement in the time resolution and signal intensity is expected in the optical arrangements using separate lens for each pulse and in the arrangements using a cutoff secondary lens with a main lens. lens.

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Fractal coding of Textural Images (텍스처 영상의 프락탈 코딩)

  • Jang, Jong-Whan
    • The Journal of Natural Sciences
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    • v.8 no.2
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    • pp.77-82
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    • 1996
  • New very low bit rate segmentation image coding technique is proposed by segmenting image into textually homogeneous regions. Regions are classified into on of three perceptually distinct texture classes (perceived constant intensity (class I), smooth texture (class II), and rough texture (class III) using the human Visual System (HVS) and the fractals. To design very low bit rate image coder, it is very important to determine nonoverlap and overlap segmentation method for each texture class. Good quality reconstructed images are obtained with about 0.10 to 0.21 bit per pixel (bpp) for many different types of imagery.

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Determination of Water with Trifluoroacetic Anhydride by NMR (Trifluoroacetic Anhydride를 이용한 NMR에 의한 수분정량)

  • 이왕규;박만기;김박광;권세호;성방훈
    • YAKHAK HOEJI
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    • v.26 no.4
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    • pp.257-260
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    • 1982
  • Measurement of water is a subject of continued interest. High resolution proton magnetic resonance has not been very effective in the determination of water. Especially spectral overlap with other proton signals from the sample is undesirable result. However, trifluoroacetic anhydride reacts with water and forms trifluoroacetic acid and the proton signal of trifluoroacetic acid did not overlap with that of samples. By use of this fact, water in acetone, ethyl ether, dioxane, dichloroethane and methyl isobutyl ketone is analyzed by high resolution proton magnetic resonance (PMR). This method is capable of detecting as little as 200ppm of $H_{2}O$. And it is very rapid, simple and accurate.

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Halftoning Method by CMY Printing Using BNM

  • Kim, Yun-Tae;Kim, Jeong-Yeop;Kim, Hee-Soo;Yeong Ho ha
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.851-854
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    • 2000
  • Digital halftoning is a technique to make an equivalent binary image from scanned photo or graphic images. Low pass filtering characteristic of human visual system can be applied to get the effect of spatial averaging of local area consisted of black and white pixels for gray image. The overlapping of black dot decreases brightness and black dot is very sensitive to human visual system in the bright region. In this paper, for gray-level expression, only bright gray region in the color image is considered for blue noise mask (BNM) approach. To solve this problem, BNM with CMY dot is used for the bright region instead of black dot. Dot-on-dot model with single mask causes the problem making much black dot overlap, color distortion. Therefore approach with three masks for C, M and Y each is proposed to decrease pixel overlap and color distortion.

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Overlap Integrals and Recoursion Formulas for Morse Wavefunction

  • Lee, Mu-Sang;Carreira, L.A.;Berkowitz, D.A.
    • Bulletin of the Korean Chemical Society
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    • v.7 no.1
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    • pp.6-12
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    • 1986
  • Overlap integrals for the case in which the ground and excited states are represented by Morse potential functions were derived. In order to calculate the spectral intensities in Morse wavefunctions, a method of expanding the wavefunctions of one state in terms of the other was developed to allow the ground and the excited state frequencies to be different. From the expansion of Morse wavefunctions, recursion formulas were developed for variational matrix elements of Morse wavefunctions. The matrix elements can be calculated using these recursion formulas and the diagonalized results which eigenvalues (allowed energies) were all successfully satisfied to Morse energy formulas.

Analysis on Durability Performance of Spot Welding by the Status of Over-Slam Bumper in Hood System (후드 오버슬램범퍼 조립 상태에 따른 점용접의 내구성능 영향 분석)

  • Lee, Hyuk
    • Journal of Applied Reliability
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    • v.17 no.4
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    • pp.273-279
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    • 2017
  • Purpose: Recently, Issues on security for vehicles are getting increased all around the world. Especially, hood panel needs to be thinner for the protection of pedestrians. But thinner panel makes durability get worse. So, it is needed to satisfy both of them. Methods: Durability effectiveness will be studied because properties and assembly allowance of over-slam bumper mostly affects durability of hood panel. Overlap of over-slam bumper can be made in production line and it can affect durability of spot welding in hood inner panel. Daguchi method is used to catch the condition in which load gets smaller and location, hardness and quantity of overlap are selected to be factors. Durability effectiveness is analyzed with the factors. Result: the mechanism that affects on spot welding is identified. The test was conducted in both open/close and driving condition and the relation between both conditions is analyzed. Conclusion: The test contributed to durability of hood panel with optimization of over-slam bumper.

A Mechanism Study of a HyperSpectral Image Sensor for Nadir and Slant Range Operation (직하방과 빗각 촬영 운용을 위한 초분광 영상센서 구동방식에 관한 연구)

  • Lee, Kyeongyeon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.22 no.4
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    • pp.484-491
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    • 2019
  • General Hyperspectral Image Sensor acquires an image of line form such as a thin rectangle shape because of using 1D array Push Broom or Whisk Broom scanning method. A special mechanism is required for a Hyperspectral Image Sensor to operate for nadir and slant range. To design the mechanism, the characteristics of the flight motion and the overlap rate between consecutive frames were analyzed. Also, system requirements were proposed through modeling and simulation.

COUNTING OF FLOWERS BASED ON K-MEANS CLUSTERING AND WATERSHED SEGMENTATION

  • PAN ZHAO;BYEONG-CHUN SHIN
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.27 no.2
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    • pp.146-159
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    • 2023
  • This paper proposes a hybrid algorithm combining K-means clustering and watershed algorithms for flower segmentation and counting. We use the K-means clustering algorithm to obtain the main colors in a complex background according to the cluster centers and then take a color space transformation to extract pixel values for the hue, saturation, and value of flower color. Next, we apply the threshold segmentation technique to segment flowers precisely and obtain the binary image of flowers. Based on this, we take the Euclidean distance transformation to obtain the distance map and apply it to find the local maxima of the connected components. Afterward, the proposed algorithm adaptively determines a minimum distance between each peak and apply it to label connected components using the watershed segmentation with eight-connectivity. On a dataset of 30 images, the test results reveal that the proposed method is more efficient and precise for the counting of overlapped flowers ignoring the degree of overlap, number of overlap, and relatively irregular shape.

A Study on the Optimization of IoU (IoU의 최적화에 관한 연구)

  • Xu, Xin
    • Proceedings of the Korea Information Processing Society Conference
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    • 2020.05a
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    • pp.595-598
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    • 2020
  • IoU (Intersection over Union) is the most commonly used index in target detection. The core requirement of target detection is what is in the image and where. Based on these two problems, classification training and positional regression training are needed. However, in the process of position regression, the most commonly used method is to obtain the IoU of the predicted bounding box and ground-truth bounding box. Calculating bounding box regression losses should take into account three important geometric measures, namely the overlap area, the distance, and the aspect ratio. Although GIoU (Generalized Intersection over Union) improves the calculation function of image overlap degree, it still can't represent the distance and aspect ratio of the graph well. As a result of technological progress, Bounding-Box is no longer represented by coordinates x,y,w and h of four positions. Therefore, the IoU can be further optimized with the center point and aspect ratio of Bounding-Box.

Modeling of Instrumental Tone considering Main frequency and Harmonics (기본 주파수와 고조파 성분을 고려한 악기음의 모델링)

  • 오복환;이동규;이두수
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.1127-1130
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    • 1999
  • In this paper, using one method of Additive Synthesis, Analysis-by-synthesis/Overlap-Add (ABS/OLA) method, analysis and synthesis of musical tones is processed. But peak detection of frequency domain is processed by proposed method considering the view of acoustics. It is that that harmonics frequency is times of main frequency. Using this fact, peak detection of frequency domain is useful for detection of tonal component identified musical note. It is possible to realize high-quality lour bit rate audio.

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