• Journal of Korean Society for Quality Management
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• v.18 no.2
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• pp.33-42
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• 1990

This paper proposes the maintenance model of multi-component system when the failure characteristics and types of components are considered. In this model, it is assumed that a system is composed of a critical component, a major component and a minor component. Also, failure types is classified into major failure and minor failure. If major failure occurs to critical component before system age replacement time, the system is renewed. If major failure does not occur until its age replacement time, preventive maintenance is performed at age replacement time T. Minimal repairs are carried out after each minor failure. Major component is minimal-repaired if any failure is discovered during operation. Minor component should be replaced as soon as any failure is found. This paper determines the optimal replacement time of the system which minimizes total maintenance cost. Numerical example illustrates these results.

• The Journal of Korean Medicine
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• v.29 no.4
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• pp.55-67
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• 2008

Objectives: The purpose of this study was to investigate the effect of Hwangryunhaedok-tang, its major component Coptidis Rhizoma, and the major component of Coptidis Rhizoma, berberine, on the expression of behavioral sensitization induced by the repeated administration of nicotine. Methods: Experimental ratswere divided into 3 groups and each group treated with saline, nicotine, and Hwangryunhaedok-tang. Experiments were performed on 4 further groups, each group treated with saline, nicotine, Coptidis Rhizoma, and berberine. To obtain rats addicted todrugs, nicotine was injected repeatedly. After 3 days of withdrawal phase, on the 11th day, rats were re-exposed to nicotine and thus able to induce the expression of the activity sensitization phenomenon successfully. To examine the change of c-Fos in the brain of experimental rats with the nicotine-induced activity sensitization, their neurological activation rate was assessed by c-Fos staining with Fos-like immunihistochemistry of the dopamine releasing area, the striatum and the nucleus accumbens. Results: The result demonstrate that Hwangryunhaedok-tang, its major component Coptidis Rhizoma and berberine,the major component of Coptidis Rhizoma, significantly reduced the walking activity rate in the drug addict models induced by nicotine administration, and Coptidis Rhizoma and its major component berberine reduce the marker of the neurological activation c-Fos, and thus revealed an effect of suppressing drug addiction. Conclusions: These results suggest the possibility of Hwangryunhaedok-tang, its major component Coptidis Rhizoma and the major component of Coptidis Rhizoma, berberine,as therapeutic for nicotine addiction.

• Journal of Korean Society for Quality Management
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• v.21 no.2
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• pp.109-120
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• 1993

Most systems are composed of components which have different failure chracteristics. Since the failure characteristics of components is different, it is rational and reasonable to establish a maintenance model to be considered repair and replacement policies which are proper to failure characteristics of these components. This paper proposes the age replacement time for a system composed of components which have different failure characteristics. In this model, it is assumed that a system is composed of a critical failure component, a major failure component, minor failure component. If any failure occurs to critical component before its age replacement time, the system should be replaced. If any failure does not occur until its age replacement time, preventive replacement should be performed at age replacement time T. Major component is minimal repaired if any failure occurs during operation. Minor component should be replaced as soon as failure is found. This paper determines the optimal replacement time of the system which minimize, total maintenance cost and initial stock Quantity of minor component within this optimal replacement time. Numerical example illustrates these results.

• Journal of Communications and Networks
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• v.12 no.2
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• pp.191-197
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• 2010

In this paper, we propose a novel methodology to identify border gateway protocol (BGP) updates associated with major events - affecting network reachability to multiple ASes - and separate them (statistically) from those attributable to minor events, which individually generate few updates, but collectively form the persistent background noise observed at BGP vantage points. Our methodology is based on principal component analysis, which enables us to transform and reduce the BGP updates into different AS clusters that are likely affected by distinct major events. We demonstrate the accuracy and effectiveness of our methodology through simulations and real BGP data.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.11 no.18
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• pp.35-39
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• 1988

In general, the characteristics of components which consist of multi component system can not be the same. This paper proposes a maintenance model of multi-component system according to the characteristics of each component. In this paper multi-component system is divided into three components-critical component, major component and minor component, respectively. Then we determine the optimal age replacement time of the system which minimizes total maintenance cost. Numerical examples are shown to illustrate the result.

• Journal of the Korean Graphic Arts Communication Society
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• v.16 no.3
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• pp.157-170
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• 1998

To investigate the most effective way of cellulase utilization on paper making process and the systematic way of how to combine its components for better use, purified two major cellulase were applied to bleached kraft pulp at various dosage in the refining process and estimated the synergism effect of each components in the characteristics of papermaking fiber. freeness was not changed by $C_1$ Component dosage but strongly increased by Cx Component dosage. Drop in fiber viscosity, increase in WQV, fiber shortening and fine generation was strongly influenced by Cx Component, it seems to be that Cx Component works a hydrogenate that breaks hydrogen bonding in fiber and enhances pooling effect of fiber. $C_1$ Component was little influenced these characteristics of fiber but considered to help to make fiber surface smooth.

• Journal of Korean Society for Quality Management
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• v.17 no.1
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• pp.1-10
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• 1989

In general, the characteristics of components which consist of multi-component system can not be the same. This paper proposes a maintenance model of multi-component system considering the characteristics of each component. In this paper, multi-component system is divided into three components-critical unit, major unit and minor unit, respectively. This paper determines the optimal replacement time of the system which minimizes total maintenance cost, optimal replacement period of major unit and initial stock quantity of minor unit within this optimal replacement time. Numerical examples are shown when the failure times of each unit have gamma distribution.

• Journal of Society of Preventive Korean Medicine
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• v.7 no.1
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• pp.133-138
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• 2003

It is well known that Dioscoreae Rhizoma tonifies and benefits the Spleen and Stomach, benefits the Lung and nourishes the Kidney. A major component isolated from this herb consist of dioscin, diosgenin, allantoin, starch, alanin, mucilage, choline, amylase, and glycoprotein. In this study, we aimed to measure the content of allantoin, one of major component, to determine the quality of Dioscoreae Rhizoma.

• Proceedings of the PSK Conference
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• 2003.10a
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• pp.56-56
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• 2003

Carduus marianus extract (formally called silymarin) have been used mainly as a medicament for hepatobiliary diseases. The major component of silymarin is silybin, which constitutes between 50 and 70% of the drug and is the major active component. Many experiments show the efficacy of silybin parenterally administerated. But, its bioavailability is low after oral administration due to its low solubility in water. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.296.2-296.2
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• 2003

Carduus marianus extract (formally called silymarin) have been used mainly as a medicament for hepatobiliary diseases. The major component of silymarin is silybin, which constitutes between 50 and 70％ of the drug and is the major active component. Many experiments show the efficacy of silybin parenterally administerated. But, its bioavalability is low after oral administration due to its low solubility in water. (omitted)