• Journal of Ginseng Research
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• 제15권3호
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• pp.179-182
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• 1991

The relationship between the brain monoamines and morphine tolerance was examined in ginseng total saponins treated mice. Ginseng total saponins (100 mg/kg, i.p.) did not antagonize morphine (10 mg/kg, s.c.) analgesia in mice. Daily treatment with ginseng total saponins (100 mg/kg) did not affect the brain levels of noradrenaline, dopamine and serotonin for 5 days but inhibited the development of morphine tolerance. This inhibition of the development of morphine tolerance was not attributed to the reductions of brain noradrenaline, dopamine and serotonin in mice treated with ginseng total saponins (100 mg/kg) daily. This result suggest that a newly equilibrated state of neurologic function may involve an underlying mechanism in mice treated with ginseng total saponins.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 학술대회지
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• pp.693-698
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• 2004

The cyber attacks on the computer system in nowadays are focused on works that do not operate specific application. The main key point that we protect information security system has an access control to keep an application. Most of system has a main function to protect an infrastructure such as hardware, network and operating system. In this paper, we have presented an intrusion tolerance system that can service an application in spite of cyber attacks. The proposed system is based on the middle ware integrating security mechanism and separate function of application and intrusion tolerance. The main factor we use security system in nowadays is service to keep a persistency. The proposed intrusion tolerance system is applicable to such as medical, national defense and banking system.

• 한국CDE학회논문집
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• 제10권4호
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• pp.284-292
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• 2005

This paper presents a new framework of kinematic tolerance synthesis and describes the implemented algorithm for planar mechanical systems comprised of higher kinematic pairs. Input to the synthesis algorithm is a parametric model of the mechanical system with allowed parameter ranges (tolerance ranges). The model is specified as the part profiles consisting of line and arc segments and the motion axes along which each part moves. The algorithm analyzes tolerance in generalized configuration space, called contact zones bounding the worst-case variations, and identifies bad system variations. The bad system variations then are removed out of the parameter ranges by adjusting the nominal parameter values if possible and then shrinking the ranges otherwise. This cycle is repeated until no more bad variations we found. I show the effectiveness of the algorithm by case studies on several mechanisms.

• The Korean Journal of Ecology
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• 제19권1호
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• pp.36-46
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• 1996

Variation of Al tolerance in Pinus densiflora, P. rigida and P. thunbergii was investigated in a solution culture. Root length decreased as Al concentration increased, and decreased more in dilute culture media than in dense one. Aluminum tolerance based on relative root length was in the order of P. rigida ＞ P. densiflora ＞ P. thunbergii. Al content in tissue increased as Al concentration of the media increased, but the reverse was true for content of Ca and Mg. Al tolerance for root length showed intraspecific variation, even under the same Al concentration in the media.

• 한국유체기계학회 논문집
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• 제2권3호
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• pp.30-36
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• 1999

Blade shape profile in the axial compressor is one of the most important factors governing its aerodynamic characteristics. Manufacturing tolerance, which is inevitable in the blade manufacturing processes, may change blade profile and as a consequence, it will affect the compressor performance. In this paper, influence of manufacturing tolerance on the aerodynamic characteristics of axial compressor blades with distortion of blade profile curvatures is investigated by using a flow simulation technique. It is found that manufacturing tolerance can be an important factor affecting the source of both profile and wake losses of the axial compressor blades.

• 품질경영학회지
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• 제36권2호
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• pp.20-27
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• 2008

Tolerance design has been identified as an important research area and a number of models have been proposed in the literature. This paper investigates the effect of limited capacity on tolerance design for products with nominal-the-best type (N-type) quality characteristics. The model is developed under the assumption that the reprocessed and nonreprocessed items are produced by the same manufacturing process and therefore their quality characteristics are identically and independently distributed. Profit models are constructed which involve four price/cost components; selling price, cost incurred by imperfect quality, reprocessing and quality inspection costs. Methods of finding the optimal tolerance limits are presented, and a numerical example is given. Sensitivity analyses are also performed to study the effect of a process standard deviation on this model.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.829-832
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• 2002

With the increase of storage density, high rotational speed and high access technologies in optical disk drive, mechanical issues, mainly noise and vibration, become critical. Up to now the researches of rubber mount for anti-vibration focused on how to calculate the static and the dynamic stiffness of rubber mount and leaved out of consideration of the dimensional tolerance of rubber mount for anti-vibration. This paper presents the effects of dimensional tolerance of rubber mount for anti-vibration on the dynamic characteristics of optical disk drive by finite element analysis and dynamic test. The relation between dimensional tolerance and dynamic characteristics of optical disk drive is observed and discussed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.95-100
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• 2006

Tolerance analysis method for natural frequencies of multi-body systems having a equilibrium position is suggested in this paper. To perform the tolerance analysis, the Monte-Carlo Method is conventionally employed. However, the Monte-Carlo Method has some weakness; spending too much time for analysis and having a low accuracy and hard to converge in the numerical unstable area. To resolve these problems, a tolerance analysis method is suggested in this paper. Sensitivity equations of natural frequencies are derived at the equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivity of natural frequencies can be calculated.

• 품질경영학회지
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• 제22권1호
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• pp.133-141
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• 1994

The determination of the tolerance on the lower-level characteristics for the given upper-level characteristics is an indispensable problem in manufacturing industries. The procedure, proposed by Taguchi, for this matter can be easily applied in engineering fields due to its conceptual simplicity. However, the previously developed methods are known to have some limitations in the field applications, because the value of each major factor determining the tolerance cannot be obtained exactly. In this paper, a tolerance design procedure is proposed under the assumption that the major factors to determine the tolerance is uncertain. For the validity of the method proposed in this paper, a hypothetical problem is employed and analyzed.

• 대한산업공학회지
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• 제36권4호
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• pp.243-247
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• 2010

Every products, which made by mass production, is not identical in their size but have variations in some intervals specified by tolerance dimensions. Tolerances play major role in standardization of part and its quality, and also make a huge impact on manufacturing cost. The optimal condition for tolerances is giving the values as loose as possible for low production cost while satisfying quality specification, which usually demand tight control of tolerances. Tolerance analysis is necessary to get an optimal solution for this conflict situation. This paper have studied tolerance analysis for universal joint assembly of vehicle steering system and tried to find useful results of the study for product design and quality control.