• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.3
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• pp.107-113
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• 1989

The purpose of this study is to compare the results of shear-deformation of saturated sand under the 3 dimensional stress with the results of simple torque-shear test already reported, Japaness standard sand, Toyoura sand, was chosen as test sample and the equipments of the department of soil mechancis laboratory of Nihon University were used. The conclusions obtained are as follows. 1). The friction angle of sand (${\phi}$) is proportional to the density regardless of the condition of stress-strain. This is because of the reason that the lower the cell pressure becomes, the larger the volume changes in case of the same density. 2). The value of ${\varphi}$ are variable according to the condition of stress-strain in the same density, and ${\phi}_dTS$ is larger than ${\phi}_dPS$ and ${\phi}_dTC$ when cell pressure is low. 3). ${\phi}_dPS$ is larger then ${\phi}_dTS$, under the same denstiy and same cell pressure. Thus the shear strength of sand is decided according to the condition of stress-strain 4). the relationship between the stress ratio (q/p) and strain increment ration in the plane strain test is linear regardless of the density and the cell pressure of the test sample.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.173-178
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• 2008

In this paper, we will introduce rock physics modeling technique, which interrelate reservoir properties with seismic properties, and apply the technique to the Donghae-1 gas reservoir. From well-log data analysis, we obtained velocityporosity (Vp-$\phi$) relations for each formation. These relations can used to predict porosity from seismic data. In addition, we analyzed permeability data, which were obtained from core measurements and computational rock physics simulations. We then obtained permeability-porosity ($\kappa-\phi$) relations. Combining $\kappa-\phi$ with Vp-$\phi$ relations, we finally present quantitative Vp-$\kappa$ relations. As to Vp-$\phi$ modeling, we found that the degree of diagenesis and clay contents increase with depth. As to Vp-$\kappa$ relations, though \kappa-\phi relations are almost identical for all formations, we could obtain distinct Vp-$\kappa$ relations due to Vp-$\phi$ variations. In conclusion, the rock physics modeling, which bridges between seismic properties and reservoir properties, can be a very robust tool for quantitative reservoir characterization with less uncertainty.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.1
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• pp.67-74
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• 2000

This paper presents the analysis of partial discharge signals according to the particle states in GIS, for preventing the insulation failure and recognizing the particle states. In this paper, four states of particle (particle on electrode, particle on enclosure, particle on spacer and crossing particle) were simulated. And $\Phi$-Q-N distribution of partial discharge signals was analyzed and the statistical operator of the $\Phi$-Q distribution was analyzed. As a result, it was found that the states of particle were distinguished by analysis of the $\Phi$-Q-N distribution and the statistical operator of the $\Phi$-Q distribution.

• Korean Journal of Logic
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• v.17 no.2
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• pp.323-349
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• 2014

In this paper, we show that the standard completeness for the extension of UL with compensation-free reinforcement (cfr) $(({\phi}&{\psi}){\rightarrow}({\phi}{\wedge}{\psi})){\vee}(({\phi}{\vee}{\psi}){\rightarrow}({\phi}&{\psi}))$ can be established. More exactly, first, the compensation-freely reinforced uninorm logic $UL_{cfr}$ (the UL with (cfr)) is introduced. The algebraic structures of $UL_{cfr}$ are then defined, and its algebraic completeness is established. Next, standard completeness (i.e. completeness on [0, 1]) is established for $UL_{cfr}$ by using the method introduced in Yang (2009).

• Journal of the Korean Mathematical Society
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• v.54 no.2
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• pp.685-696
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• 2017

A linear mapping ${\phi}$ on an algebra $\mathcal{A}$ is called a centralizable mapping at $G{\in}{\mathcal{A}}$ if ${\phi}(AB)={\phi}(A)B= A{\phi}(B)$ for each A and B in $\mathcal{A}$ with AB = G, and ${\phi}$ is called a derivable mapping at $G{\in}{\mathcal{A}}$ if ${\phi}(AB)={\phi}(A)B+A{\phi}(B)$ for each A and B in $\mathcal{A}$ with AB = G. A point G in A is called a full-centralizable point (resp. full-derivable point) if every centralizable (resp. derivable) mapping at G is a centralizer (resp. derivation). We prove that every point in a von Neumann algebra or a triangular algebra is a full-centralizable point. We also prove that a point in a von Neumann algebra is a full-derivable point if and only if its central carrier is the unit.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.406-410
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• 2003

B. M. Schein([1]) considered systems of the form (${\Phi}$; ${\circ}$,-), where ${\Phi}$ is a set of functions closed under the composition "${\circ}$" of functions and the set theoretic subtraction "-". In this structure, (${\Phi}$; ${\circ}$) is a function semigroup and (${\Phi}$;-) is a subtraction algebra in the sense of [1]. He proved that every subtraction semigroup is isomorphic to a difference semigroup of invertible functions. Also this structure is closely related to the mathematical logic, Boolean algebra, Bck-algera, etc. In this paper, we define the near subtraction semigroup as a generalization of the subtraction semigroup, and define the notions of strong for it, and then we will search the general properties of this structure, the properties of ideals, and the application of it.

• BMB Reports
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• v.42 no.3
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• pp.160-165
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• 2009

The temperate Staphylococcus aureus phage ${\Phi}11$ harbors cI and cro repressor genes similar to those of lambdoid phages. Using extremely pure ${\Phi}11$ Cro (the product of the ${\Phi}11$ cro gene) we demonstrated that this protein possesses a single domain structure, forms dimers in solution at micromolar concentrations and maintains a largely $\alpha$-helical structure even at $45^{\circ}C$. ${\Phi}11$ Cro was sensitive to thermolysin at temperatures ranging from $55-75^{\circ}C$ and began to aggregate at ${\sim}63^{\circ}C$, suggesting that the protein is moderately thermostable. Of the three homologous 15-bp operators (O1, O2, and O3) in the ${\Phi}11$ cI-cro intergenic region, ${\Phi}11$ Cro only binds efficiently to O3, which is located upstream of the cI gene. Our comparative analyses indicate that the DNA binding capacity, secondary structure and dimerization efficiency of thermostable ${\Phi}11$ Cro are distinct from those of P22 Cro and $\lambda$ Cro, the best characterized representatives of the two structurally different Cro families.

• Health Policy and Management
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• v.19 no.1
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• pp.62-80
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• 2009

The purpose of this study was to examine the factors influencing the attitude toward the increasing role of private health insurance(PHI). In the Korea Welfare Panel Data 2007, a sample of 1,675 (adjusted by weight value: 1,607) respondents on an opinion on promoting PHI was used in the study. With independent variables including socio-demographic characteristics, health status, health-related behavior, and opinions on welfare service, ordered-probit model was used to analyze the attitude toward PHI. Negative opinion on the increasing role of PHI were responded by 54.6%(n=877) of the respondents, whereas 22.2%(n=373) were positive and 23.2%(n=357) were neutral. Old people, the better off, those with worse self-assessed health status, and those having an experience of health examination tend to have the positive attitude toward the increasing role of PHI. Women, those with chronic diseases or disorders and those who do not agree that comprehensive welfare benefits reduce work incentive showed negative attitude toward PHI. When comparing the needs for PHI before and after medical utilization, ex-ante need tends to strengthen the tendency to support private health insurance. This study will contribute to the discussion on the optimal mix of public and private health insurance in Korea by a better recognition of attitude toward PHI and health care system.

• Journal of Advanced Engineering and Technology
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• v.11 no.4
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• pp.253-257
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• 2018

Exhaust gas from the combustion of automobiles adversely affects the human body and even pollutes the atmosphere. This study investigated the influence of exhaust gas change on intake manifold using the nozzle. First, the flow analysis was performed using the 3D flow analysis program. When the nozzle inlet air velocity increased, the average air velocity in the nozzle diameters of ${\Phi}2.5$ and ${\Phi}5$ increased 37.3% and 31.9% respectively at the intake manifold outlet. As the nozzle inlet air velocity increased, the maximum flow rate of air increased to 42.2% and 32.6%, respectively at nozzle diameters of ${\Phi}2.5$ and ${\Phi}5$. In order to verify the analysis results, experiments on the exhaust gas were performed in the engine simulation system. As the nozzle inlet velocity increased, HC values decreased by 42.4% and 31.4% at nozzle diameters of ${\Phi}2.5$ and ${\Phi}5$, respectively. And CO values decreased by 40.7% and 31.1% at nozzle diameters of ${\Phi}2.5$ and ${\Phi}5$.

• Journal of the Korean Chemical Society
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• v.19 no.5
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• pp.289-293
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• 1975

According to the viscosity and density studies of an aqueous solution of dodecyl pyridinium chloride (DPC) it was shown that the 2nd critical micelle concentration (2nd cmc) existed in the solution in addition to the 1st cmc. The volume fraction ${\phi}_m$ of the hydrated micelle was calculated by using the following equation: ${\Pi}_{rm}=1+2.5{\phi}_m+14.1{\phi}_m^2$ It has been found that the increment of ${\phi}_m$ in the ${\phi}_m$ vs. $C_m$ curve decreased at near the 2nd cmc. And the partial specific volume ($\={v}$) of DPC obtained from the density measurement also decreased rapidly at near the 2nd cmc and remains constant value above the 2nd cmc. This may be attributed to a change in the micelle structure at the 2nd cmc caused by a variation in the type of aggregation and by a decrease in the counterion binding by the micelle.