• Title/Summary/Keyword: Edge projection

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Lane Detection and Tracking Algorithm for 3D Fluorescence Image Analysis (3D 형광이미지 분석을 위한 레인 검출 및 추적 알고리즘)

  • Lee, Bok Ju;Moon, Hyuck;Choi, Young Kyu
    • Journal of the Semiconductor & Display Technology
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    • v.15 no.1
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    • pp.27-32
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    • 2016
  • A new lane detection algorithm is proposed for the analysis of DNA fingerprints from a polymerase chain reaction (PCR) gel electrophoresis image. Although several research results have been previously reported, it is still challenging to extract lanes precisely from images having abrupt background brightness difference and bent lanes. We propose an edge based algorithm for calculating the average lane width and lane cycle. Our method adopts sub-pixel algorithm for extracting rising-edges and falling edges precisely and estimates the lane width and cycle by using k-means clustering algorithm. To handle the curved lanes, we partition the gel image into small portions, and track the lane centers in each partitioned image. 32 gel images including 534 lanes are used to evaluate the performance of our method. Experimental results show that our method is robust to images having background difference and bent lanes without any preprocessing.

Development of Database Supported Graph Library and Graph Algorithms (데이터베이스에 기반한 그래프 라이브러리 및 그래프 알고리즘 개발)

  • 박휴찬;추인경
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.6 no.5
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    • pp.653-660
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    • 2002
  • This paper proposes a method for storing graphs and defining graph algorithms based on the well-developed relational database. In this method, graphs are represented in the form of relations. Each vertex and edge of a graph is represented as tuples of the table and saved in a database. We developed a library of graph operations for the storage and management of graphs and the development of graph applications. Furthermore, we defined graph algorithms in terms of relational algebraic operations such as projection, selection, and join. They can be implemented with the database language such as SQL. This database approach provides an efficient methodology to deal with very large-scale graphs and to support the development of graph applications.

3D Automatic Mesh Generation Scheme for the Boundary Element Method (경계요소법을 위한 3차원 자동요소분할)

  • Lee, H.B.;Lee, S.H.;Kim, H.S.;Lee, K.S.;Hahn, S.Y.
    • Proceedings of the KIEE Conference
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    • 1993.07b
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    • pp.935-937
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    • 1993
  • This paper presents a three dimensional automatic mesh generation scheme for the boundary element method, and this scheme can be applicable to practical problems of complex shape. The geometry of the problem is expressed as an assemblage of linear Coon's surfaces, and each surface is made up of four edge curves which are defined in the form of a parametric function. Curves are automatically segmented according to their characteristics. With these segments of curves, interior points and triangular mesh elements are generated in the parametric plane using Lindholm's method, and then their projection on the real surface forms the initial mesh. The refinement of initial mesh is performed so that the discrete triangular planes are close to the real continuous surfaces. The bisection method is used for the refinement. Finally, interior points in the refined mesh are rearranged so as to make each element be close with an equilateral triangle. An attempt has been made to apply the proposed method to a DY(Deflection Yoke) model.

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Resistance, electron- and laser-beam welding of zirconium alloys for nuclear applications: A review

  • Slobodyan, Mikhail
    • Nuclear Engineering and Technology
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    • v.53 no.4
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    • pp.1049-1078
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    • 2021
  • The review summarizes the published data on the widely applied electron-beam, laser-beam, as well as resistance upset, projection, and spot welding of zirconium alloys for nuclear applications. It provides the results of their analysis to identify common patterns in this area. Great attention has been paid to the quality requirements, the edge preparation, up-to-date equipment, process parameters, as well as post-weld treatment and processing. Also, quality control and weld repair methods have been mentioned. Finally, conclusions have been drawn about a significant gap between the capabilities of advanced welding equipment to control the microstructure and, accordingly, the properties of welded joints of the zirconium alloys and existing algorithms that enable to realize them in the nuclear industry. Considering the ever-increasing demands on the high-burnup accident tolerant nuclear fuel assemblies, great efforts should be focused on the improving the welding procedures by implementing predefined heat input cycles. However, a lot of research is required, since the number of possible combinations of the zirconium alloys, designs and dimensions of the joints dramatically exceeds the quantity of published results on the effect of the welding parameters on the properties of the welds.

Observation of Dynamic Movement of Probing Pin on PCB Pad Using Electrical Reliability Test (인쇄회로 기판의 전기검사에서의 미세 탐침과 패드의 동적 거동 현상 관측)

  • Song, Seongmin;Cha, Gangil;Kim, Myungkyu;Jeon, Seungho;Yu, SangSeok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.3
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    • pp.245-251
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    • 2015
  • In an electrical reliability test of a printed circuit board (PCB), the impact of the micro probing pins on the PCB needs to be checked to ascertain the quality of the circuit. In this study, the impact of the dynamic movement of the probing pin on the pad was observed. As a misaligned pin can exert horizontal force on the pad of the PCB, this study focused on the behavior of a misaligned probing pin. The parameters of observation were the circular and flat edges of the probing pin. The effects of the speed of movement, diameter, and the length of projection of the probing pin were also investigated. The results demonstrated that slippage angle is strongly affected by the shape of the edge of the probing pin, and that projection length is an important factor affecting pin slippage. In contrast, the speed of movement of the probing pin was able to double the slippage angle.

A Study on a Multiresolution Filtering Algorithm based on a Physical Model of SPECT Lesion Detectability (SPECT 이상조직 검출능 모델에 근거한 다해상도 필터링 기법 연구)

  • Kim, Jeong-Hui;Kim, Gwang-Ik
    • Journal of Biomedical Engineering Research
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    • v.19 no.6
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    • pp.551-562
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    • 1998
  • Amultiresolution filtering algorithm based on the physical SPECT lesion detachability provides and optimal solution for SPECT reconstruction problem. Related to the previous study, we estimated the SPECT lesion detection capability by m minimum detectable lesion sizes (MDLSs), and generated m reconstruction filters which are designed to maximize the smoothing effect at a fixed MDLS-dependent resolution level $\frac{MDLS}{4\sqrt{2In2}}$. The proposed multiresolution filtering algorithm used a coarse-to-fine approach for the m-level resolution filter images obtained from these m filters for a given projection image. First, the local homogeneity is determined for every pixel of the filter images, by comparing the local variance value computed in a window centered at the pixel and the mode determined from the distribution of the local variances. Based on the local homogeneity, the pixels declared as homogeneous are chosen from the filter image of the lowest resolution, and for the other pixels the same process is repeated for the higher resolution filter images. For the non-homogeneous pixels after this pixels after this repetition process ends, the pixel values of the highest resolution filter image are substituted. From the results of the simulated experiments, the proposed multiresolution filtering algorithm showed a strong smoothing effect in the homogeneous regions and a significant resolution improvement near the edge regions of the projection images, and so produced good adaptability effects in the reconstructed images.

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Automated Algorithm for Super Resolution(SR) using Satellite Images (위성영상을 이용한 Super Resolution(SR)을 위한 자동화 알고리즘)

  • Lee, S-Ra-El;Ko, Kyung-Sik;Park, Jong-Won
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.2
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    • pp.209-216
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    • 2018
  • High-resolution satellite imagery is used in diverse fields such as meteorological observation, topography observation, remote sensing (RS), military facility monitoring and protection of cultural heritage. In satellite imagery, low-resolution imagery can take place depending on the conditions of hardware (e.g., optical system, satellite operation altitude, image sensor, etc.) even though the images were obtained from the same satellite imaging system. Once a satellite is launched, the adjustment of the imaging system cannot be done to improve the resolution of the degraded images. Therefore, there should be a way to improve resolution, using the satellite imagery. In this study, a super resolution (SR) algorithm was adopted to improve resolution, using such low-resolution satellite imagery. The SR algorithm is an algorithm which enhances image resolution by matching multiple low-resolution images. In satellite imagery, however, it is difficult to get several images on the same region. To take care of this problem, this study performed the SR algorithm by calibrating geometric changes on images after applying automatic extraction of feature points and projection transform. As a result, a clear edge was found just like the SR results in which feature points were manually obtained.

Characterization of Deep Learning-Based and Hybrid Iterative Reconstruction for Image Quality Optimization at Computer Tomography Angiography (전산화단층촬영조영술에서 화질 최적화를 위한 딥러닝 기반 및 하이브리드 반복 재구성의 특성분석)

  • Pil-Hyun, Jeon;Chang-Lae, Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.1
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    • pp.1-9
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    • 2023
  • For optimal image quality of computer tomography angiography (CTA), different iodine concentrations and scan parameters were applied to quantitatively evaluate the image quality characteristics of filtered back projection (FBP), hybrid-iterative reconstruction (hybrid-IR), and deep learning reconstruction (DLR). A 320-row-detector CT scanner scanned a phantom with various iodine concentrations (1.2, 2.9, 4.9, 6.9, 10.4, 14.3, 18.4, and 25.9 mg/mL) located at the edge of a cylindrical water phantom with a diameter of 19 cm. Data obtained using each reconstruction technique was analyzed through noise, coefficient of variation (COV), and root mean square error (RMSE). As the iodine concentration increased, the CT number value increased, but the noise change did not show any special characteristics. COV decreased with increasing iodine concentration for FBP, adaptive iterative dose reduction (AIDR) 3D, and advanced intelligent clear-IQ engine (AiCE) at various tube voltages and tube currents. In addition, when the iodine concentration was low, there was a slight difference in COV between the reconstitution techniques, but there was little difference as the iodine concentration increased. AiCE showed the characteristic that RMSE decreased as the iodine concentration increased but rather increased after a specific concentration (4.9 mg/mL). Therefore, the user will have to consider the characteristics of scan parameters such as tube current and tube voltage as well as iodine concentration according to the reconstruction technique for optimal CTA image acquisition.

Effects of TGF-$\beta$3 on Epithelial-mesenchymal transformation and Epidermal growth factor receptor expression in palatogenesis of chicken embryo (계태아 발생시 TGF-$\beta$3가 구개판 내측돌기상피의 상피간엽변환 및 상피성장인자수용체 발현에 미치는 영향)

  • Yang Byoung-Eun;Lee Jong-Ho
    • Korean Journal of Cleft Lip And Palate
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    • v.4 no.1
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    • pp.13-26
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    • 2001
  • Cleft lip and/or palate is the congenital orofacial malformation most commonly occurred in humans, The disease is multifactorial and is probably caused by genetic and/or environmental factors, So, there are many problems in research concerning etiology and in treatment of the disease, Even the most practiced and sophisticated methods of surgical repair are necessarily followed by scar contraction and fibrosis, which result in skeletal defects, dental abnormalities, cosmetic disfigurement, and speech impairment, As a result, Fetal surgery can be considered but practiced rarely when the deformity is not fatal to life, And treatment of cleft palate is performed in the form of medicine projection into uterus in animal experiments, Many studies show that growth factor and its receptor emerge from the developing palate; and the epidermal growth factor receptors have a important role in craniofacial development and in palatal fusion, The palatal morphogenesis of the avine is different from the mammal's; it takes the form of physiologic cleft palate, Recently, cleft palate fusion experiment was performed when the avine were in the period of palate formation through the exogenous TGF-β3 addition, and it showed that the exogenous TGF-β3 makes fusion of divided palate through certain process when cleft palate is occurred in palatal formation, In this study, I had the conformation of the fusion of cleft palate through the addition of TGF-β in case of chicken embryo, and observed the effect of TGF-β in EGF receptor distribution, And the following is the results of this study, 1. In case of the TGF-βl and β3 addition group, there was the decrease of EGFR(Epidermal Growth Factor Receptor) immunoreactivity in mesenchymal cells beneath the medial edge epithelium and also in epithelial mesenchymal interface which is between medial edge epithelium and nasal septum in 72 hours, 2, The immunoreactivity of the control group resembles that of normal chicken embryo palate in development, 3. In the view through fluorescence confocal microscopy, there was confluence in TGF-β3 addition group, This shows that the confluence induced by exogenous TGF-β3 is related to EGFR expression in palate of chicken embryo, which is a physiologic cleft palate model.

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Improvement of Building Region Correspondence between SLI and Vector Map Based on Region Splitting (영역분할에 의한 SLI와 벡터 지도 간의 건물영역 일치도 향상)

  • Lee, Jeong Ho;Ga, Chill O;Kim, Yong Il;Yu, Ki Yun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.4
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    • pp.405-412
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    • 2012
  • After the spatial discrepancy between SLI(Street-Level Imagery) and vector map is removed by their conflation, the corresponding building regions can be found based on SLI parameters. The building region correspondence, however, is not perfect even after the conflation. This paper aims to improve the correspondence of building regions by region splitting of an SLI. Regions are initialized by the seed lines, projection of building objects onto SLI scene. First, sky images are generated by filtering, segmentation, and sky region detection. Candidates for split lines are detected by edge detector, and then images are splitted into building regions by optimal split lines based on color difference and sky existence. The experiments demonstrated that the proposed region splitting method had improved the accuracy of building region correspondence from 83.3% to 89.7%. The result can be utilized effectively for enhancement of SLI services.