• Title/Summary/Keyword: Shape prior

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Statistical Approach to Noisy Band Removal for Enhancement of HIRIS Image Classification

  • Huan, Nguyen Van;Kim, Hak-Il
    • Proceedings of the KSRS Conference
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    • 2008.03a
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    • pp.195-200
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    • 2008
  • The accuracy of classifying pixels in HIRIS images is usually degraded by noisy bands since noisy bands may deform the typical shape of spectral reflectance. Proposed in this paper is a statistical method for noisy band removal which mainly makes use of the correlation coefficients between bands. Considering each band as a random variable, the correlation coefficient measures the strength and direction of a linear relationship between two random variables. While the correlation between two signal bands is high, existence of a noisy band will produce a low correlation due to ill-correlativeness and undirectedness. The application of the correlation coefficient as a measure for detecting noisy bands is under a two-pass screening scheme. This method is independent of the prior knowledge of the sensor or the cause resulted in the noise. The classification in this experiment uses the unsupervised k-nearest neighbor algorithm in accordance with the well-accepted Euclidean distance measure and the spectral angle mapper measure. This paper also proposes a hierarchical combination of these measures for spectral matching. Finally, a separability assessment based on the between-class and within-class scatter matrices is followed to evaluate the performance.

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A 3-dimensional Printed Molding Technique for the Management of Humeral Head Osteomyelitis

  • Moon, Young Lae;dev Bhardwaj, Harvinder;Kim, Boseon;Ryu, Kang Hyeon
    • Clinics in Shoulder and Elbow
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    • v.20 no.1
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    • pp.46-48
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    • 2017
  • There are many methods of making cement spacer in patients who require a two-staged operation for humeral head osteomyelitis. However, limitation of motion after the first surgery-due to inadequate size and insufficient intra-articular space for second surgery-remain to be an issue. To mitigate this issue, we made a cement spacer with the same size and shape of the patient humeral head. Four patients with humeral head osteomyelitis were enrolled in this study. To make the cement spacer, we used the Mimics program, and designed the molding box by a reverse engineering technique. We evaluated the range of motion and pain using a Constant score. The mean abduction was $50^{\circ}$($40^{\circ}-60^{\circ}$), forward flexion was $50^{\circ}$ ($30^{\circ}-70^{\circ}$), and average Constant score was 47.75 (44-52). Three-dimensional printed molding technique is one of the effective methods for humeral head osteomyelitis allowing for daily activities prior to the second surgery.

A Study on the Background and Characteristics of Textile Wallcovering in Flemish Painting (플랑드르 회화에 표현된 벽걸이 직물의 발달 배경과 특징에 관한 연구)

  • Lee, Joonhan;Kim, Sun Mee
    • Journal of Fashion Business
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    • v.24 no.4
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    • pp.19-29
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    • 2020
  • The purpose of this study was to investigate Renaissance wall-covering fabrics through Flemish paintings, that provides the details of the origin and development of background of modern wallcovering. The methods of the study are as follows. First, the background of textile development of Flanders in the 14th to 16th centuries were examined through a prior study. Second, the shape and use of wallcoverings in paintings painted during that time were analyzed and the process of changing to modern forms was studied. The residential environment with many stone buildings in relatively humid and cold weather created a need for decorative fabrics. Back then, the wool and flax fabric were not allowed to be worn on the body, so the materials were used for the development of interior fabrics. The characteristics of wall covering in Flemish paint can be summarized with movable, allegory, and decoration. Movable stems from the arrival of the emerging aristocrats of Flanders, who had enormous commercial trade and carried decorative fabrics; the mobility has become an allegory in reality as the royal and aristocratic use of wall-decorated fabrics is the symbol of authority. In addition, unlike Italy, where silk was procured from the East, fabrics manufactured using flax and wool were not suitable for clothing in terms of religion and practicality and were used to decorate walls.

Region of Interest Detection Based on Visual Attention and Threshold Segmentation in High Spatial Resolution Remote Sensing Images

  • Zhang, Libao;Li, Hao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.8
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    • pp.1843-1859
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    • 2013
  • The continuous increase of the spatial resolution of remote sensing images brings great challenge to image analysis and processing. Traditional prior knowledge-based region detection and target recognition algorithms for processing high resolution remote sensing images generally employ a global searching solution, which results in prohibitive computational complexity. In this paper, a more efficient region of interest (ROI) detection algorithm based on visual attention and threshold segmentation (VA-TS) is proposed, wherein a visual attention mechanism is used to eliminate image segmentation and feature detection to the entire image. The input image is subsampled to decrease the amount of data and the discrete moment transform (DMT) feature is extracted to provide a finer description of the edges. The feature maps are combined with weights according to the amount of the "strong points" and the "salient points". A threshold segmentation strategy is employed to obtain more accurate region of interest shape information with the very low computational complexity. Experimental statistics have shown that the proposed algorithm is computational efficient and provide more visually accurate detection results. The calculation time is only about 0.7% of the traditional Itti's model.

Distribution of Silver Particles in Silver-containing Activated Carbon Fibers

  • Ryu, S.K.;Eom, S.Y.;Cho, T.H.;Edie, D.D.
    • Carbon letters
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    • v.4 no.4
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    • pp.168-174
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    • 2003
  • Silver nitrate ($AgNO_3$) powder was mixed into a reformed pitch precursor. Then, the silver-containing pitch was melt spun to form round and "C" shape fibers. A wire mesh was inserted prior to the nozzle to improve the spinnability of the silvercontaining precursor pitch. Silver particles in the carbon fibers (CFs) were detected by XRD and TEM. These tests showed that silver particles were uniformly distributed and the total amount of silver remained constant during stabilization and carbonization. Next, the silver-containing CFs were activated by steam diluted in nitrogen gas. Silver particles accelerated the activation rate, but the specific surface areas of the silver-containing ACFs were similar to those of non-silver containing ACFs at the same burn-off levels. The specific surface area of the C-shaped activated carbon fibers was larger than that of the round activated carbon fibers. The likely reason is that the surface area of a C-shaped CF is about two times larger than that of a round CF when equivalent cross-sectional areas are compared. A small amount of silver particles in the periphery of the CFs was removed during the activation, but the remainder of silver was stayed within the ACFs.

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Synthesis of Cubic Boron Nitride by Al-Mg Solvents

  • Park, Jong-Ku;Park, S.T.;S.K. Singhal;S. J. Cui;K. Y. Eun
    • The Korean Journal of Ceramics
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    • v.3 no.3
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    • pp.187-190
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    • 1997
  • The aluminum-magnesium (Al-Mg) aklloys have been proved to be an effective solvent for synthesis of cubic-phase boron nitride (cBN) from hexagonal-phase boron nitride (hBN) at the conditions of high pressures and high temperatures (HP/HT). Various kinds of hBN powders having different crystallinity have been tested for cBN synthesis with Al-Mg solvents. The conversion ratio from hBN to cBN and the shape of synthesized cBN crystals appeared to be affected strongly by chemical composition and added amount of Al-Mg solvents as well as crystallinity of BN powders. As the magnesium content increased in the Al-Mg solvents, the conversion ratio increased and the size of cBN crystals became larger. The crystal facets developed well in the specimens with solvents having high Mg content. It was observed that a hBNlongrightarrowcBN transformation occurred more easily in the specimens having well crystallized hBN powders. Amorphous BN having much $B_2O_3$ impurity exhibited a low threshold temperature for transformation to cBN, which was attributed to crystallization of amorphous BN to well crystallized hBN prior to transformation into cBN with help of $B_2O_3$.

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MAP Kinase Activation is Required for the MMP-9 Induction by TNF-Stimulation

  • Kim, Kyung-Chan;Lee, Chu-Hee
    • Archives of Pharmacal Research
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    • v.28 no.11
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    • pp.1257-1262
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    • 2005
  • MMP-9 is a metalloproteinase capable of basement membrane degradation in vivo. Expression of MMP-9 can be found in normal conditions such as trophoblasts, osteoclasts, and leukocytes and their precursors. They also occur as well as in pathological conditions, such as the invasive growth of primary tumors, metastasis, angiogenesis, rheumatoid arthritis, and periodontal diseases. MMP-9 upregulation can be highly induced by a wide range of agents. These agents include growth factors, cytokines, cell-cell, and cell-ECM adhesion molecules, and agents altering cell shape. Here, we observed that TNF-$\alpha$ stimulated human monocytic cell line, HL-60 produced MMP-9 in a dose and time dependent manner. Real time PCR results indicated transcriptional upregulation of MMP-9 as early as 3 h post TNF-$\alpha$ stimulation. To investigate the signaling pathway underlined in TNF-$\alpha$ induced MMP-9 expression, three MAP kinase inhibitors were added to cells 1 h prior to TNF-$\alpha$ treatment. The ERK inhibitor completely abolished MMP-9 expression by TNF-$\alpha$. But neither p38 MAP kinase nor JNK inhibitor had an effect on TNF-$\alpha$ induced MMP-9 expression, suggesting that ERK activation is required for the MMP-9 induction by TNF-$\alpha$. Taken together, we found that TNF-$\alpha$ stimulation facilitates ERK activation, which results in the transcriptional upregulation of MMP-9 gene and subsequent MMP-9 production and secretion.

Robust Face Detection Based on Knowledge-Directed Specification of Bottom-Up Saliency

  • Lee, Yu-Bu;Lee, Suk-Han
    • ETRI Journal
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    • v.33 no.4
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    • pp.600-610
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    • 2011
  • This paper presents a novel approach to face detection by localizing faces as the goal-specific saliencies in a scene, using the framework of selective visual attention of a human with a particular goal in mind. The proposed approach aims at achieving human-like robustness as well as efficiency in face detection under large scene variations. The key is to establish how the specific knowledge relevant to the goal interacts with the bottom-up process of external visual stimuli for saliency detection. We propose a direct incorporation of the goal-related knowledge into the specification and/or modification of the internal process of a general bottom-up saliency detection framework. More specifically, prior knowledge of the human face, such as its size, skin color, and shape, is directly set to the window size and color signature for computing the center of difference, as well as to modify the importance weight, as a means of transforming into a goal-specific saliency detection. The experimental evaluation shows that the proposed method reaches a detection rate of 93.4% with a false positive rate of 7.1%, indicating the robustness against a wide variation of scale and rotation.

The study of the breakup mechanism of a liquid jet by using a high speed camera (고속도카메라에 의한 액주의 분열기구에 관한 연구)

  • 김덕줄;이충원
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.13 no.4
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    • pp.708-716
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    • 1989
  • The purpose of this study is to investigate the breakup mechanism of a liquid jet in a coaxial air flow. By using the high speed camera, measured were the instantaneous change of the wave length, amuplitude of disturbance, propagation velocity of wave and breakup length, and the relationships between those data were examined. The shape of the surface of the liquid jet appeared to be rather complicated and irregular. The growth rate of disturbance was not constant, and was changed at the moment of 3ms prior to the disintegration of the liquid jet. Simultaneously at this moment, the propagation velocities of the sequential waves were reversed and the wave length was rapidly decreased.

Development of On-line Life Monitoring System Software for High-temperature Components of Power Boilers (보일러 고온요소의 수명 감시시스템 소프트웨어 개발)

  • 윤필기;정동관;윤기봉
    • Proceedings of the Korea Society for Energy Engineering kosee Conference
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    • 1999.05a
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    • pp.171-176
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    • 1999
  • Nondestructive inspection and accompanying life analysis based on fracture mechanics were the major conventional methods for evaluating remaining life of critical high temperature components in power plants. By using these conventional methods, it has been difficult to perform in-service inspection for life prediction. Also, quantitative damage evaluation due to unexpected abrupt changes in operating temperature was almost impossible. Thus, many efforts have been made for evaluating remaining life during operation of the plants and predicting real-time life usage values based on the shape of structures, operating history, and material properties. In this study, a core software for on-line life monitoring system which carries out real-time life evaluation of a critical component in power boiler(high temperature steam headers) is developed. The software is capable of evaluating creep and fatigue life usage from the real-time stress data calculated by using temperature/stress transfer Green functions derived for the specific headers and by counting transient cycles. The major benefits of the developed software lie in determining future operating schedule, inspection interval, and replacement plan by monitoring real-time life usage based on prior operating history.

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