• Journal of Korean Society of Transportation
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• v.7 no.1
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• pp.5-18
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• 1989

Understanding the future level of car ownership is essential in order to formulate various transportation policies. Despite its importance, however, a revies of literature indicates that previous studies treated car ownership as a linear function of income, GNP, degree of urbanization and etc. more detaild and accurate models of car ownership should be possible if information on major variables determining car ownership can be gathered. In this paper, three approaches have been chosen to develop mathematical models to predict future increase in car ownership in Korea. The three methords developed are : income distribution methords ; multiple regression models ; forecasting curves.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1992.04b
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• pp.403-412
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• 1992

This note examines a situation where a risk-neutral insurer and a risk-averse individual (prospective insured) negotiate to reach an arbitration point of the price of insurance over the terms of an insurance contract in order to maximize their respective self-interests. The situation is modeled as a Nash bargaining problem. We analyze the dependence of the price of insurance, which is determined by the Nash solution, on the parameters such as the size of insured loss, the probability of a loss, the degree of risk-aversion of the insured, and the riskiness of loss distribution.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.09a
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• pp.377-380
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• 2004

To identify the effect of landfill waste for groundwater and unsaturated air environment, soil gas survey and hydrogeochemical study were executed. The geology of the study area is granite and aquifer is mainly composed of sandy soil. The results of spatial distribution from soil gas showed the boundary of buried waste and processes and degree of waste decomposition. Groundwater contamination by leachate from landfill is controlled by groundwater flow attributed by the original topography and liner.

• Journal of applied mathematics & informatics
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• v.19 no.1_2
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• pp.427-438
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• 2005

From a notion of d-pseudo-orthogonality for a sequence of poly-nomials ($d\;\in\;{2,3,\cdots}$), this paper introduces three different characterizations of natural exponential families (NEF's) with polynomial variance functions of exact degree 2d-1. These results provide extended versions of the Meixner (1934), Shanbhag (1972, 1979) and Feinsilver (1986) characterization results of quadratic NEF's based on classical orthogonal polynomials. Some news sets of polynomials with (2d-1)-term recurrence relation are then pointed out and we completely illustrate the cases associated to the families of positive stable distributions.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.207-210
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• 2003

In this research analyzed the daily precipitation depths of 4 climatic stations in south eastern part of Korea. It aimed to present some indices for regionalization of the area. The items are frequency distributions of precipitation quantity and days and the longest days less than class limit set up by arithmetic differences. The regression analysis between class value and frequency show very good correlation coefficients better than 0.99 which are cubic equation for the precipitation, exponential equation for the precipitation days, and first degree equation for the longest day less than class limit.

• International Journal of Reliability and Applications
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• v.9 no.1
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• pp.1-5
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• 2008

A heuristic algorithm for reliability optimization of a distributed network system is developed so that the reliability of a large system can be determined efficiently. This heuristic bases on the determination of maximal reliability set of maximum node capacity, maximal link reliability and maximal node degree.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1992.10a
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• pp.39-44
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• 1992

This paper is concerned with formulations of the hierarchical $C^{o}$-plate element on the basis of Reissner-Mindlin plate theory. On reason for the development of the aforementioned element is that it is still difficult to construct elements based on h-version concepts which are accurate and stable against the shear locking effects. An adaptive mesh refinement and selective p-distribution of the polynomial degree using hp-version of the finite element method we proposed to verify the superior convergence and algorithmic efficiency with the help of the clamped L-shaped plate problems.s.

• Communications of the Korean Mathematical Society
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• v.16 no.2
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• pp.297-308
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• 2001

A partial ordering is developed here among conditionally positive quadrant dependent (CPQD) bivariate random vectors. This permits us to measure the degree of CPQD-ness and to compare pairs of CPQD random vectors. Some properties and closure under certain statistical operations are derived.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1998.06a
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• pp.17-24
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• 1998

This paper deals with the springback characteristics of cold rolled sheet steel through the use of the V-bending process and U-bending one. The influence of material properties on the springback of forming processes was investigated. In the V-bending process there was an optimum bend radius for each combination of parameters which produced minimal springback. In the U-bending process the blank holder force can control the degree of springback. A high blank holding force resulted in a uniform strain distribution and reduced the level of springback.

• Bulletin of the Korean Chemical Society
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• v.20 no.11
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• pp.1319-1322
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• 1999

Leucine zipper dynamically tunes the degree of bifurcation of the DNA binding segments in the basic region of the Fos-Jun bZIP complex. Molecular dynamics simulation indicated that site-specific mutagenesis of conserved leucine residues inside the leucine zipper domain caused the change of dynamic behavior of the basic region, and efficient DNA binding occurs only within a certain range of distance between the two DNA binding segments in the basic region. Distribution of α-helices in the hinge region is also suggested to influence the bifurcation of the DNA binding segments.