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Analytical Method to Analyze the Effect of Tolerance on the Modal Characteristic of Multi-body Systems in Dynamic Equilibrium (동적 평형위치에 있는 다물체계의 모드특성에 미치는 공차의 영향 분석을 위한 해석적 방법)

  • Kim, Bum-Suk;Yoo, Hong-Hee
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.05a
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    • pp.109-114
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    • 2007
  • Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo Method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo Method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated at the dynamic equilibrium position. The effect of tolerance on the modal characteristic can be analyzed from tolerance analysis method.

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Tolerance Control for the Inner Open-Switch Faults of a T-Type Three-Level Rectifier

  • Lee, June-Seok;Lee, Kyo-Beum
    • Journal of Power Electronics
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    • v.14 no.6
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    • pp.1157-1165
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    • 2014
  • The T-type topology is a three-level topology that has an advantage in terms of its number of switching device and its efficiency when compared to the neutral-point clamped (NPC)-type topology. With the recent increase in the usage of the T-type topology, the interest in its reliability has also increased. Therefore, a tolerance control for a T-type rectifier is necessary to improve the reliability of applications when an open-switch fault occurs. NPC-type rectifiers cannot eliminate input current distortion completely. However, the T-type rectifier is able to restore distorted current. In this paper, a tolerance control for the $S_{x2}$ and $S_{x3}$ open-switch faults of a T-type rectifier is proposed where it is advantageous in terms of efficiency when compared with other tolerance controls. The performance of the proposed tolerance control is verified through simulation and experimental results.

Oral Tolerance: Not Simple But more Complex

  • Chung, Yeonseok;Kang, Chang-Yuil
    • IMMUNE NETWORK
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    • v.3 no.3
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    • pp.169-175
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    • 2003
  • The intestinal immune system can discriminate between harmful and unharmful antigens and do not provoke productive immunity to unharmful antigen. Thus oral administration of antigen is one of classical methods for inducing antigen-specific immune tolerance in the periphery. Furthermore, oral tolerance has been investigated for the treatment of autoimmune disorders in human clinical trials. However, the detail mechanism of oral tolerance and contributing factors are not defined clearly at this time. Recent studies demonstrate unique types of immune cell that suppressing immune response, such as regulatory T cell and tolerogenic dendritic cell. This article reviews the factors involved in oral tolerance and discusses our current understanding base on the recent literatures and our works.

A Study on Tolerance Design of Mechanisms using the Taguchi Method (다구찌 기법을 이용한 기구의 공차설게에 관한 연구)

  • 박경호;한형석;박태원
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.813-818
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    • 1996
  • This paper presents a method for tolerance design using the Taguchi Method(TM) and general purpose mechanism analysis program. Also the tolerance design method is with respect to performance improvement of a mechanism. To use the orthogonal array, mathematical model of a mechanism is established and experiments are carried out by the general purpose mechanism analysis program. The contact model is used to consider a clearance effect. This method is applied to the tolerance design of the VTR Deck mechanism. This method can be used in tolerance design of general mechanisms.

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Effect of Ginseng Saponin on the Analgesic Effect and Tolerance Development of Clonidine

  • Kim, Hack-Seang;Park, Seung-Ki;Hwang, Seong-Lok;Oh, Ki-Wan;Lee, Myung-Koo
    • Korean Journal of Pharmacognosy
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    • v.21 no.1
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    • pp.103-109
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    • 1990
  • The antagonism against clonidine-induced analgesia by ginseng saponin (GS) and the inhibitory effect of GS on the development of clonidine-induced tolerance were evaluated in mice. GS, when administered systemically, intracerebrally and intrathecally, antagonized significantly the analgesic effect of clonidine. GS, when injected intraperitoneally not only inhibited the development of clonidine-induced analgesic tolerance, but also enhanced the analgesic effect of clonidine on the 2nd and 5th day. Naloxone did not antagonize the analgesic effect of clonidine and had no influence on the deveolpment of tolerance of both acute and delayed types. These results indicate that the antagonism against clonidine-induced analgesia and the inhibition of the deveolpment of clonidine-induced tolerance by GS are not mediated by the opioid mechanism.

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Effects of Ginseng Saponins on the Development and Loss of Morphine Tolerance and Dependence

  • Kim, Hack-Seang;Oh, Sei-Kwan;Choi, Kang-Ju;Park, Jung-Sup
    • Korean Journal of Pharmacognosy
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    • v.17 no.2
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    • pp.139-147
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    • 1986
  • Ginseng saponins(GS), protopanaxadiol saponins(PD) and protopanaxatriol saponins (PT) were tested for the inhibition of the development of morphine tolerance and dependence antagonism of morphine analgesia and the loss of morphine tolerance and dependence in mice The results were as follows: 1. Inhibition of the development of morphine tolerance and dependence. 2. Antagonism of morphine analgesia. 3. Increase in the loss of morphine tolerance and dependence. Antagonism of morphine by ginseng saponins and its reversal by L-DOPA and 5-HTP suggest some possibility that catecholamines and serotonin levels might be associated with the results.

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Tolerance Analysis and Design Improvement of a Lens System for Mobile Phone Camera (휴대폰용 카메라 모듈의 렌즈 시스템에 대한 공차 해석 및 설계 개선에 관한 연구)

  • Jung, Sang-Jin;Choi, Byung-Lyul;Choi, Dong-Hoon;Kim, Ju-Ho
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1063-1068
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    • 2008
  • A lens system of a camera module for mobile phones is comprised of the composition and design of various shapes of lens. To improve responses such as the modular transfer function (MTF), a lens system should always be constructed by considering uncertainty that can be caused by manufacturing and assembly error. In this study, tolerance optimization using the Latin Hypercube Sampling (LHS) technique is performed. In order to reduce the computational burden of the tolerance optimization process and decrease the influence from numerical noise effectively, we use the Progressive Quadratic Response Surface Modeling (PQRSM), which is one of Sequential Approximate Optimization (SAO) techniques. Using this method, we achieved optimal tolerance for each lens and obtained reliability for satisfying user‘s requirements. In addition, through the design process the manufacturing and assembly cost of a lens system was reduced.

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Molecular Analysis of Freeze-Tolerance Enhanced by Treatment of Trinexapac-Ethyl in Kentucky Bluegrass

  • Hwang, Cheol Ho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.44 no.2
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    • pp.176-179
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    • 1999
  • Trinexapac-ethyl[ 4-(cyclopropyl- $\alpha$ -hydroxy-methylene)-3,5-dioxocyclohexane carboxylic acid ethylester] is a growth-retardant for plants by inhibiting a key step in biosynthesis of GA. A treatment of trinexapacethyl generally induces a reduction in vegetative growth and also inhibits heading. In addition, the trinexapacethyl was known to enhance the freeze-tolerance in annual bluegrass, however, the mechanism is not known yet. One possible reason for the enhanced freeze-tolerance may be the antifreeze protein known to be accumulated in intercellular space of the leaf during cold acclimation. In order to see the possible in-duction of the synthesis of antifreeze proteins by trinexacpacethyl, the apoplastic proteins extracted from Kentucky bluegrass treated with trinexapacethyl were analyzed by SDS-PAGE and the presence of the antifreeze protein was observed. In addition, western analysis showed the identity of the protein induced by both a cold acclimation and a trinexapacethyl treatment. It appears that an enhanced freeze-tolerance of the turf grass by trinexapacethyl is due to the synthesis and/or accumulation of the antifreeze protein similar to the enhanced freeze tolerance induced by cold acclimation.

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An Estimate of the Mediation Effect of Risk Tolerance among Marital Status, Gender, and Investing Behavior

  • Heo, Wookjae;Grable, John E.;Nobre, Liana;Ruiz-Menjivar, Jorge
    • International Journal of Human Ecology
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    • v.17 no.1
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    • pp.1-14
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    • 2016
  • This paper presents a series of path models that were developed to test whether financial risk tolerance mediates the association between the following four variables and investing behavior: (a) male and married, (b) female and married, (c) male and single, or (d) female and single. Data for this study were obtained from a proprietary consumer survey of risk-tolerance attitudes. Four path models were developed to test relationships among the variables in 2008, 2009, 2010, and 2011. These years were chosen to represent the depth and recovery periods in the Great Recession. The total number of respondents was 29,641. Findings showed that financial risk tolerance was positively associated with risky investing behavior (i.e., equity ownership) in each of the four periods. The associations among the gender-marital status variables and investing behavior were mixed; however, findings did indicate that risk tolerance mediates these relationships by sometimes amplifying and occasionally attenuating risky behavior. Based on the findings, implications and limitation are presented.

Extraction and Specification of Requirements for Intrusion Tolerant Software Modeling (침입감내 소프트웨어 모델링을 위한 요구사항 추출 및 명세)

  • 조은숙;이강신
    • Journal of the Korea Society for Simulation
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    • v.13 no.1
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    • pp.51-63
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    • 2004
  • Current distributed systems are attacked from the outside as well as in which new intrusions are occurred. In particular there is a growing but largely unnoticed intrusion threat due to the emerging middleware technologies such as CORBA, WAP, XML support, and enterprise application integrators. In order to cope with these attacks, intrusion tolerance technology is introduced. Intrusion tolerance technology means that it can provide services normally although attacks are occurred into system. There are intrusion tolerance architectures such as ITUA, HACQIT, SITAR, and so on as a part of DARPA project. In this paper, we analyze and discuss existing intrusion tolerance architectures with respect to intrusion tolerance technology. Also, we extract intrusion tolerant requirements, which are required to develop ,intrusion tolerant system. We propose UML-IT(Intrusion Tolerance) profiles and specify intrusion tolerant software by applying UML-IT profiles.

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