• Title/Summary/Keyword: Jong-Hwa AN

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Analytical Method of additive in Polyester (I) (폴리에스테르의 첨가제 분석법(I))

  • Jung, Jong Hwa;Lee, Kyeong Hee
    • Analytical Science and Technology
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    • v.12 no.1
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    • pp.84-88
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    • 1999
  • A method to analyze additives in a polyester resin has been studied by utilizing a centrifuge and a thin layer chromatography. Identification of the separated organic and inorganic compounds were carried out by spectrophotometers, such as NMR, UV-VIS, IR and XRD. For the polyester resin studied in this research contained organic and inorganic compounds which were found to be a dimer form of 2-phenylbenzoazole and an anatase form of $TiO_2$, respectively.

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Improved Modular Inversion over GF(p)

  • Choi, Jong-Hwa;Kim, Yong-Dae;Ahn, Young-Il;You, Young-Gap
    • International Journal of Contents
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    • v.3 no.2
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    • pp.40-43
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    • 2007
  • This paper proposed a new modular inverse algorithm based on the right-shifting binary Euclidean algorithm. For an n-bit numbers, the number of operations for the proposed algorithm is reduced about 61.3% less than the classical binary extended Euclidean algorithm. The proposed algorithm implementation shows substantial reduction in computation time over Galois field GF(p).

Image Enhancement Method by Saturation and Contrast Improvement

  • Park, Gyu-Hee;Cho, Hwa-Hyun;Yun, Jong-Ho;Choi, Myung-Ryul
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1139-1142
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    • 2007
  • In this paper, an image enhancement method by saturation and contrast improvement is proposed. Histogram equalization with color difference makes higher contrast. By generating saturation amplification ratio with color difference, the saturation improves effectively. The experimental results show that the proposed algorithm has higher contrast and more natural - look than the conventional methods.

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A Design of Nonlinear Time-varying Fuzzy PID Controller for Position Control System using Embeded-sensor-type Hydraulic Cylinder

  • Park, Jang-Ho;Kim, Jin-Gyu;Ryu, Gi-Seok;Lee, Byung-Geul;Kim, Jong-Hwa
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.68.2-68
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    • 2001
  • A position control system using hydraulic cylinder is modeled as a nonlinear system. In order to control this nonlinear system, in this paper, the fuzzy PID control technique which has time-varying control parameters is adopted. In this study, an exclusive sensor to detect the position of hydraulic cylinder is used, which is embeded in hydraulic cylinder.

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A Study on the Integrated Simulator Scheme for Communication Networks (통신망 통합시뮬레이터의 구축방안에 관한 연구)

  • Kwon, Ho-Yeol;Kim, Hwa-Jong
    • Journal of Industrial Technology
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    • v.12
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    • pp.37-49
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    • 1992
  • We proposed an integrated simulator scheme for communication networks. The network modeling and Analysis methologies are firstly discussed along the design procedure of a network simulator, and then, the structure, kernel, and user interfaces are defined for the simulator. Finally, for the verification of our approach, simulations are performed for a simple queueing network and a pure ALOHA system using Ptolemy, a multi-paradigm simulation enviroment.

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An Encryption Method for Wearable Sensor Data Based on Time Synchronization (웨어러블 센서데이터를 위한 시각 동기화 기반 암호화 방법)

  • Choi, JongHwa;Ahn, Sanghyun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2016.10a
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    • pp.138-139
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    • 2016
  • 웨어러블 기기들의 환경은 저성능부터 고성능으로 다양하게 있다. 성능이 제한적인 기기에 대해서는 공개키 암호화 방식을 사용하여 지속적으로 통신하기에 어려웅움이 있다. 본 연구에서는 시각 정보를 이용한 비밀키 암호화 방식을 제안한다.

NONPARAMETRIC ONE-SIDED TESTS FOR MULTIVARIATE AND RIGHT CENSORED DATA

  • Park, Hyo-Il;Na, Jong-Hwa
    • Journal of the Korean Statistical Society
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    • v.32 no.4
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    • pp.373-384
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    • 2003
  • In this paper, we formulate multivariate one-sided alternatives and propose a class of nonparametric tests for possibly right censored data. We obtain the asymptotic tail probability (or p-value) by showing that our proposed test statistics have asymptotically multivariate normal distributions. Also, we illustrate our procedure with an example and compare it with other procedures in terms of empirical powers for the bivariate case. Finally, we discuss some properties of our test.