• Title/Summary/Keyword: method of sciences

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Design for Microstrip Patch Antenna with Dual Frequency and Dual Polarization for W-CDMA System

  • Min, Kyeong-Sik;Park, Se-Hyun;Kim, Dong-Chul;Hiroyuki Arai
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.05a
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    • pp.276-279
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    • 1999
  • This paper proposes a design for microstrip patch antenna with dual resonance and dual polarization fed by proximity coupled quarter wavelength stub. The antenna characteristics are analyzed by the FDTD method with Mur's 2nd order ABC. From the simulation results based on the FDTD method, frequency characteristics of structure parameters such as the patch size and the offset feed are investigated. The numerical results are compared with the experimental results, and the comparison shows reasonable agreement for a design frequency.

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CONVERGENCE OF PARALLEL MULTISPLITTING METHODS USING ILU FACTORIZATIONS

  • Yun, Jae-Heon;Oh, Se-Young;Kim, Eun-Heui
    • Journal of applied mathematics & informatics
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    • v.15 no.1_2
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    • pp.77-90
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    • 2004
  • In this paper, we study the convergence of both relaxed multisplitting method and nonstationary two-stage multisplitting method associated with a multisplitting which is obtained from the ILU factorizations for solving a linear system whose coefficient matrix is an H-matrix. Also, parallel performance results of nonstaionary two-stage multisplitting method using ILU factorizations as inner splittings on the IBM p690 supercomputer are provided to analyze theoretical results.

Integrated Modeling for the Design of Deformable Mirrors Using a Parametric Module Method

  • Zhu, Junqing;Sha, Wei;Chen, Changzheng;Zhang, Xingxiang;Ren, Jianyue
    • Journal of the Optical Society of Korea
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    • v.19 no.5
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    • pp.521-530
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    • 2015
  • Active optics is a key technology for future large-aperture space telescopes. In the design of deformable mirrors for space applications, the design parameter trade-off between the number of regularly configured actuators and the correction capability is essential but rarely analyzed, due to the lack of design legacy. This paper presents a parametric module method for integrated modeling of deformable mirrors with regularly configured actuators. A full design parameter space is explored to evaluate the correction capability and the mass of deformable mirrors, using an autoconstructed finite-element parametric modeling method that utilizes manual finite-element meshing for complex structures. These results are used to provide design guidelines for deformable mirrors. The integrated modeling method presented here can be used for future applied optics projects.

Real-time Automatic Target Tracking Based on a Fast Matching Method (고속정합법에 의한 실시간 자동 목표 추적)

  • 김세환;김남철
    • Proceedings of the Korean Institute of Communication Sciences Conference
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    • 1987.04a
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    • pp.60-66
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    • 1987
  • In this paper a fast matching method using subtemplate and search and down technique to reduce very heavy computational load of the conventional matching method, is presented The proposed method is spplied to an automatic target tracker in order to track one moving object in comparatively simple backgoriund. Experimental results show that istperformanced is not so degraded in spite of high computational reduction as that of the conventional matching method.

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Nitrate uptake of the red tide dinoflagellate Prorocentrum micans measured using a nutrient repletion method: effect of light intensity

  • Lee, Kyung Ha;Jeong, Hae Jin;Kim, Hye Jeong;Lim, An Suk
    • ALGAE
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    • v.32 no.2
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    • pp.139-153
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    • 2017
  • The ability of a red tide species to take up nutrients is a critical factor affecting its red tide dynamics and species competition. Nutrient uptake by red tide species has been conventionally measured by incubating nutrient-depleted cells for a short period at 1 or 2 light intensities. This method may be applicable to certain conditions under which cells remain in oligotrophic water for a long time and high nutrients are suddenly introduced. Thus, a new method should be developed that can be applicable to the conditions under which cells are maintained in eutrophicated waters in healthy conditions and experience light and dark cycles and different light intensities during vertical migration. In this study, a new repletion method reflecting these conditions was developed. The nitrate uptake rates of the red tide dinoflagellate Prorocentrum micans originally maintained in nitrate repletion and depletion conditions as a function of nitrate concentration were measured. With increasing light intensity from 10 to $100{\mu}E\;m^{-2}s^{-1}$, the maximum nitrate uptake rate ($V_{max}$) of P. micans increased from 3.6 to $10.8 pM\;cell^{-1}d^{-1}$ and the half saturation constant ($K_{s-NO3}$) increased from 4.1 to $6.9{\mu}M$. At $20{\mu}E\;m^{-2}s^{-1}$, the $V_{max}$ and $K_{s-NO3}$ of P. micans originally maintained in a nitrate repletion condition were similar to those maintained in a nitrate depletion condition. Thus, differences in cells under nutrient repletion and depletion conditions may not affect $K_{s-NO3}$ and $V_{max}$. Moreover, different light intensities may cause differences in the nitrate uptake of migratory phototrophic dinoflagellates.

A Three-Dimensional Deep Convolutional Neural Network for Automatic Segmentation and Diameter Measurement of Type B Aortic Dissection

  • Yitong Yu;Yang Gao;Jianyong Wei;Fangzhou Liao;Qianjiang Xiao;Jie Zhang;Weihua Yin;Bin Lu
    • Korean Journal of Radiology
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    • v.22 no.2
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    • pp.168-178
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    • 2021
  • Objective: To provide an automatic method for segmentation and diameter measurement of type B aortic dissection (TBAD). Materials and Methods: Aortic computed tomography angiographic images from 139 patients with TBAD were consecutively collected. We implemented a deep learning method based on a three-dimensional (3D) deep convolutional neural (CNN) network, which realizes automatic segmentation and measurement of the entire aorta (EA), true lumen (TL), and false lumen (FL). The accuracy, stability, and measurement time were compared between deep learning and manual methods. The intra- and inter-observer reproducibility of the manual method was also evaluated. Results: The mean dice coefficient scores were 0.958, 0.961, and 0.932 for EA, TL, and FL, respectively. There was a linear relationship between the reference standard and measurement by the manual and deep learning method (r = 0.964 and 0.991, respectively). The average measurement error of the deep learning method was less than that of the manual method (EA, 1.64% vs. 4.13%; TL, 2.46% vs. 11.67%; FL, 2.50% vs. 8.02%). Bland-Altman plots revealed that the deviations of the diameters between the deep learning method and the reference standard were -0.042 mm (-3.412 to 3.330 mm), -0.376 mm (-3.328 to 2.577 mm), and 0.026 mm (-3.040 to 3.092 mm) for EA, TL, and FL, respectively. For the manual method, the corresponding deviations were -0.166 mm (-1.419 to 1.086 mm), -0.050 mm (-0.970 to 1.070 mm), and -0.085 mm (-1.010 to 0.084 mm). Intra- and inter-observer differences were found in measurements with the manual method, but not with the deep learning method. The measurement time with the deep learning method was markedly shorter than with the manual method (21.7 ± 1.1 vs. 82.5 ± 16.1 minutes, p < 0.001). Conclusion: The performance of efficient segmentation and diameter measurement of TBADs based on the 3D deep CNN was both accurate and stable. This method is promising for evaluating aortic morphology automatically and alleviating the workload of radiologists in the near future.

Desitgn of push-push osciplier using even-odd mode analysis (Even-odd mode 해석을 이용한 push-push osciplier의 설계)

  • 주한기;송명선;임성준
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.2
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    • pp.514-525
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    • 1996
  • In this paper, Push-push Osciplier(Oscillator + Multiplier) has been analyzed by even-odd mode analysis method. A 10GHz DRO, an Osciplier using 10GHz DRO design method and an Osciplier using even-odd mode analysis method were designed, fabricated and tested to verify this method. The measured results verified the validity of the analysis method using even-odd mode analysis.

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Building English-to-Korean Transliteration Dictionary Based on Pronouncing Dictionary (발음 사전에 기반한 영.한 음차 표기 사전의 구축)

  • Lee, Do-Gil
    • Phonetics and Speech Sciences
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    • v.1 no.3
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    • pp.103-108
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    • 2009
  • This paper proposes a method for building a transliteration dictionary, which is based on pronouncing information extracted from two kinds of existing dictionaries. Also, it proposes a method for transforming the pronouncing information into Korean translitered words. To express the pronouncing information, we define Phoman code system. In order to avoid phonetic estimation process of English words which is the most important problem, the proposed method uses the pronouncing information extracted from the existing dictionaries. Therefore, unlike previous approaches, the proposed method does not need any incomplete phonetic estimation process so that it can produce accurate transliteration results. The proposed method has been fully implemented.

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