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Vibration Behavior of a Rotating Brush Roll in Contact with a Solid Roll (강체롤과 접촉 회전하는 브러시롤의 진동 현상)

  • 허주호
    • Journal of KSNVE
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    • v.7 no.3
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    • pp.499-509
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    • 1997
  • During the process of oxide removal from work rolls in sheet metal manufacture, filamentary brushes frequently exhibit a bouncing or chatter behavior. The dynamics of this phenomenon is investigated through the development of expressions for the non-linear contact stiffness between the brush and the roll. With formulation of simple structural models, the time responses in the presence and absence of friction under random excitation are investigated. Possible solutions for the minimization or avoidance of this bouncing or chatter problem are also suggested.

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The effect of rotation on piezo-thermoelastic medium using different theories

  • Othman, Mohamed I.A.;Ahmed, Ethar A.A.
    • Structural Engineering and Mechanics
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    • v.56 no.4
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    • pp.649-665
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    • 2015
  • The present paper attempts to investigate the propagation of plane waves in generalized piezo-thermoelastic medium under the effect of rotation. The normal mode analysis is used to obtain the expressions for the displacement components, the temperature, the stress and the strain components. Comparisons are made with the results predicted by different theories (Coupled theory, Lord-Schulman, Green-Lindsay) in the absence and presence of rotation.

Validation of Radioanalytical Techniques for Nuclear Waste Characterisation

  • Warwick, Phillip E.
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.4
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    • pp.363-373
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    • 2019
  • Waste characterisation associated with nuclear site decommissioning relies on radiochemical analysis of a diverse range of sample types, requiring extensive validation of analytical techniques using matrix-matched materials. The absence of relevant reference materials has hindered robust method development and validation. The paper discusses how method validation in support of nuclear waste characterisation can be achieved without using reference materials. The key stages in an analytical procedure are evaluated and a multi-stage approach is proposed with the ultimate aim of determining an operational envelope for an analytical procedure.

Triple Negative Breast Cancer

  • Cetin, Idil;Topcul, Mehmet
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2427-2431
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    • 2014
  • Triple-negative breast cancers (TNBC), characterized by absence of the estrogen receptor (ER) and progesterone receptor (PR) and lack of overexpression of human epidermal growth factor receptor 2 (HER2), have a poor prognosis. To overcome therapy limitations of TNBC, various new approaches are needed. This mini-review focuses on discovery of new targets and drugs which might offer new hope for TNBC patients.

Spectral Analysis of Four Term Differential Operator

  • Oluoch, Nyamwala Fredrick
    • Kyungpook Mathematical Journal
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    • v.50 no.1
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    • pp.15-35
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    • 2010
  • By strengthening dichotomy condition and weakening decay conditions, we show that a four term 2n-th order differential operator with unbounded coefficients is nonlimit-point. Using stringent conditions we show that the deficiency index of this operator is determined by the behaviour of the coefficients themselves. Similarly, we prove the absence of singular continuous spectrum and that the absolutely continuous spectrum has multiplicity two.

New Species of Genus Coeloplana (Ctenophora: Tentaculata: Platyctenida) from Korea

  • Song, Jun-Im;Hwang, Sung-Jin
    • Animal Systematics, Evolution and Diversity
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    • v.26 no.3
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    • pp.217-221
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    • 2010
  • Since November, 2006, the new creeping platyctenid ctenophore, Coeloplana anthostella n. sp., has been collected from twigs and polyp masses of encrusting dendronephthyans at a depth of 26-32 m off the coast of Munseom, Jejudo Island. This new species is distinguished from C. bocki Komai, 1920 and C. komai Utinomi, 1963 by its smaller size, the absence of dorsal papillae, and the deep scarlet colored star-shaped markings on the dorsal plane. This novel addition to ctenophore fauna is presently described and illustrated in detail.

Extension of the dynamic anti-reset windup method (다이나믹 리셋 와인드엎 방지방법의 확장)

  • 박종구;최종호
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.73-76
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    • 1996
  • This paper presents a dynamical anti-reset windup (ARW) compensation method for saturating control systems with multiple controllers and/or multiloop configuration. By regarding the difference of the controller states in the absence and presence of saturating actuators as an objective function, the dynamical compensator which minimize the objective function are derived in an integrated fashion. The proposed dynamical compensator is a closed form of the plant and controller parameters. The proposed method guarantees total stability of resulting system. An illustrative example is given to show the effectiveness of the proposed method.

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Normal State EPR Study of the n-type High-Tc Superconductors

  • Lee, Cheol-Eui;Kim, W.S.;Noh, S.J
    • Journal of Magnetics
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    • v.3 no.2
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    • pp.39-40
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    • 1998
  • Normal state EPR signals have been studied for the n-type$ high-T_c$ superconductors $Nd_{1.85}Ce_{0.15}CuO_{4-x} and Nd_2CuO_{3.6-x}F_{0.4-y}.$ Since EPR signals were observed only in quenched non-superconducting samples and were absent in furnace-cooled samples, our results suggest that no normal state EPR signals come from pure phase n-type hihg-Tc superconductors. Our observation is consistent with previously reported absence of nomal state EPR signals in the p-type high-Tc superconductors.

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Day Stay Anesthesia in Dentistry

  • Lee, Doo-Ik
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.1 no.1 s.1
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    • pp.5-9
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    • 2001
  • Day stay anesthesia should include: rapid smooth onset; rapid recovery without residual side effects; absence of adverse effects (N/V); and providing postoperative analgesia. General anesthesia with multi-modalities (inhalation, intravenous and local anesthesia) may be preferable in day stay surgery. Future studies on new drugs and techniques for day stay anesthesia need comparing the increased coat of newer treatments with the potential financial savings resulting from earlier hospital discharge, reduced supplemental drugs, and earlier return to work.

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Decentralized Control for Multimachine Power Systems with Nonlinear Interconnections and Disturbances

  • Jung, Kyu-Il;Kim, Kwang-Youn;Yoon, Tae-Woong;Gilsoo Jang
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.83.3-83
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    • 2002
  • $\textbullet$ In this paper, a robust decentralized excitation control scheme is proposed $\textbullet$ We prove that the proposed control system is practically stable $\textbullet$ The origin is globally uniformly asymptotically stable in the absence of the disturbance $\textbullet$ If assumption is not satisfied, the proposed control system is still guarantees L2 stability $\textbullet$ Simulations for a three-machine power system demonstrates the effectiveness of the proposed scheme

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