• Computers and Concrete
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• v.21 no.2
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• pp.181-187
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• 2018

In order to solve the life prediction problem of damaged coating steel bar in magnesium cement concrete, this study tries to establish the marginal distribution function by using the corrosion current density as a single degradation factor. Representing the degree of steel corrosion, the corrosion current density were tested in electrochemical workstation. Then based on the Copula function, the joint distribution function of the damaged coating was established. Therefore, it is indicated that the corrosion current density of the bare steel and coated steel bar can be used as the boundary element to establish the marginal distribution function. By using the Frank-Copula function of Copula Archimedean function family, the joint distribution function of the damaged coating steel bar was successfully established. Finally, the life of the damaged coating steel bar has been lost in 7320d. As a new method for the corrosion of steel bar under the multi-dimensional factors, the two-dimensional Copula function has certain practical significance by putting forward some new ideas.

• Communications for Statistical Applications and Methods
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• v.26 no.6
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• pp.583-589
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• 2019

Counterexamples of a skew-normal distribution are developed to improve our understanding of this distribution. Two examples on bivariate non-skew-normal distribution owning marginal skew-normal distributions are first provided. Sum of dependent skew-normal and normal variables does not follow a skew-normal distribution. Continuous bivariate density with discontinuous marginal density also exists in skew-normal distribution. An example presents that the range of possible correlations for bivariate skew-normal distribution is constrained in a relatively small set. For unified skew-normal variables, an example about converging in law are discussed. Convergence in distribution is involved in two separate examples for skew-normal variables. The point estimation problem, which is not a counterexample, is provided because of its importance in understanding the skew-normal distribution. These materials are useful for undergraduate and/or graduate teaching courses.

• Journal of Nutrition and Health
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• v.22 no.2
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• pp.91-101
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• 1989

This study was performed to investigate the effects of different dietary magnesium levels on systolic blood pressure and mineral distribution in normotensive and spontaneously hypertensive rats. In experiment 1, Normotensive rats(NTR ; Sprague Dawley, Female) were given diets containing regular magnesium (0.05% Mg ; rMg), marginal magnesium (0.01% Mg ; mMg) or marginal magnesium with stress(0.01% Mg + stress ; mMg + Str). In experiment 2, spontaneously hypertensive rats (SHR ; Kyoto Wistar, Femal) were fed diets containing regular magnesium(0.05% Mg ; rMg) and high magnesium (0.2% Mg ; hMG). The following were found ; 1) NTR treated with marginal magnesium with stress showed significant increase in systolic blood pressure (SBP). Marginal magnesium diet without stress resulted in nonsignificant increase in SBP. Significant in crease of blood pressure showed in NTR treated with marginal magnesium and stress was associated with decreased magnesium and increased calcium content in femur, reticulocyte and plasma. 2) In experiment 2, magnesium supplementation to SHR showed significant attenuation of their systolic blood pressure with increasing age. The attenuation of SBP showed in SHR was associated with increased magnesium, lowered calcium content in cardiac muscle and reticulocyte and decreased plasma sodium and aldosterone level.

• The Journal of Asian Finance, Economics and Business
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• v.3 no.4
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• pp.5-16
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• 2016

Prior literature expects a lower marginal cash value for weaker governance firms. We test this empirical hypothesis by using the sample of publicly traded Korean firms from 2005 to 2013. To measure the quality of governance structures, we employ the corporate governance scores provided by Korean Corporate Governance Services. The empirical model of Faulkender and Wang (2006) is adopted to estimate the marginal value of cash. Our empirical analysis shows a higher marginal value of cash for the good governance firms in the examination of the total governance score. This finding is consistent to the agency view of cash policy predicting a larger marginal value of cash for the firms with higher governance scores. However, this positive relationship is not robust for a subset of detailed governance scores; a lower marginal cash value is observed for the firms with better qualities of board structure, auditing, dividend policies. Moreover, our empirical analysis verifies a quite low level of marginal cash value for Korean firms, which supports the existence of severe agency conflicts in Korean corporations. Our results verify the significant role of agency conflicts between a manager and shareholders in the determination of marginal cash values in the Korean firms.

• Journal of Periodontal and Implant Science
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• v.36 no.2
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• pp.473-488
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• 2006

Adequate bone quality and stress distribution to the bone are of decisive importance for implant success. Even though the success rates of dental implants have been high, implant failures do occur. Overloading has been identified as a primary factor behind dental implant failure. The purpose of this study was to theoretically investigate the effect of two types of implants on the stress distribution in poor bone quality. Employing the finite element method, the study modeled a 4.1 mm diameter, 12.0 mm length implant placed in cortical or spongeous bone. A static loading of lOON was applied at the occlusal surface at 0, 30 degrees angle to the vertical axis of the implant. von Mises stresses concentrations in the supporting bone were analyzed with finite element analysis program. The results were as follows; 1. The stresses at the marginal bone were higher under buccal oblique load(30 degrees off of the long axis) than under vertical load. 2. Under buccal oblique load, the stresses were higher at the lingual marginal bone than at the buccal marginal bone, and the differences were almost the same. 3, Under vertical and oblique load, the stress was the highest at the marginal bone and lowest at the bone around apical portions of implant in cortical bone. 4, Under vertical load, Model 1 showed more effective stress distribution than Model 2 irrespective of bone types. On the other hand, Model 2 showed lower stress concentration than Model 1 under buccal oblique load.

• The Journal of Asian Finance, Economics and Business
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• v.3 no.4
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• pp.67-79
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• 2016

Prior literature expects a lower marginal cash value for weaker governance firms. We test this empirical hypothesis by using the sample of publicly traded Korean firms from 2005 to 2013. To measure the quality of governance structures, we employ the corporate governance scores provided by Korean Corporate Governance Services. The empirical model of Faulkender and Wang (2006) is adopted to estimate the marginal value of cash. Our empirical analysis shows a higher marginal value of cash for the good governance firms in the examination of the total governance score. This finding is consistent to the agency view of cash policy predicting a larger marginal value of cash for the firms with higher governance scores. However, this positive relationship is not robust for a subset of detailed governance scores; a lower marginal cash value is observed for the firms with better qualities of board structure, auditing, dividend policies. Moreover, our empirical analysis verifies a quite low level of marginal cash value for Korean firms, which supports the existence of severe agency conflicts in Korean corporations. Our results verify the significant role of agency conflicts between a manager and shareholders in the determination of marginal cash values in the Korean firms.

• Journal of the Korean Data and Information Science Society
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• v.25 no.5
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• pp.1107-1116
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• 2014

In this paper, we review recent developments in network analysis using the graph theory, and introduce ongoing research area with relevant theoretical results. In specific, we introduce basic notations in graph, and conditional and marginal approach in constructing the adjacency matrix. Also, we introduce the Marcenko-Pastur law, the Tracy-Widom law, the white Wishart distribution, and the spiked distribution. Finally, we mention the relationship between degrees and eigenvalues for the detection of hubs in a network.

• The Korean Journal of Applied Statistics
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• v.20 no.1
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• pp.117-132
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• 2007

In a $2\times2$ table showing binary agreement between two raters, it is known that Cohen's $\kappa$, a chance-corrected measure of agreement, has two paradoxes. $\kappa$ is substantially sensitive to raters' classification probabilities(marginal probabilities) and does not satisfy conditions as a chance-corrected measure of agreement. However, $\kappa$ and other established measures have a reasonable and similar value when each marginal distribution is close to 0.5. The objectives of this paper are to present a new measure of agreement, H, which resolves paradoxes of $\kappa$ by adjusting unbalanced marginal distributions and to compare the proposed measure with established measures through some examples.

• Journal of Energy Engineering
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• v.14 no.3 s.43
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• pp.167-172
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• 2005

This paper presents a methodology to support decision making for distribution system planning based on value. To evaluate the reliability value, we employ valued-based distribution reliability assessment. To evaluate the harmonics value, we employ a marginal pricing method, and by using reliability cost, harmonics cost, and construction cost, we can make the most economic decision. By applying the method to the real system, we show this method can get the best result which meet reliability and harmonics level.

• Asian Journal of Turfgrass Science
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• v.10 no.1
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• pp.13-20
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• 1996

This study was carried out to investigate the characteristics of spatial distributon patterns of users by each type of recreational activities at lawn areas in the parks. Study sites were lawn areas at Kyungju World and Seorabul Plaza in Bomun Resort Complex in Kyungju, Korea. Space types by each recreation activities are Repose Type, Sports Type, Play Type and Strolling Type. Main results are as follows ; 1. Sport Type activities were mainly distributed at the central areas of each lawn areas. 2.The density of Sports Type activities were affected by the form of lawn areas. For natural control of excess dynamic activities, Complex Form has more advantage in the distribution of dynamic activities. So, as the form of lawn areas in the parks, complex form is more desirable. 3.Repose Typo activities were distributed at marginal areas of lawns and surrounding woods. These, the static activities, were affected by Edge Effect in spatial distribution of activities. 4.Play Typo activities also were distributed at marginal areas of lawns. It was also affected by Edge Effect in spatial distribution. 5.Strolling Type activities were distributed evenly over all lawn areas.