• 대한수학회지
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• 제33권3호
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• pp.495-505
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• 1996

Let $\Omega$ be a bounded domain in $R^d, d \geq 1$, with smooth boundary $\partial\Omega$, and let $0 < T < \infty$ be given.

• 충청수학회지
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• 제7권1호
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• pp.13-23
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• 1994

In this paper, we consider the higher-order type theoretic language L and construct a type model D of complete partial ordered set. We show that the complete partial ordered set for the language L gives rise to a category and generates a topos.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전기설비전문위원
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• pp.99-102
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• 2005

In order to development of diagnosis system for mold transformer, partial discharge measurement technique is recommended the best effective method for the evaluation of insulation condition on high voltage winding part. However, this technique was not applied to mold transformer yet. The purpose of this paper is to describe the method of partial discharge measurement for mold transformer with coupling sensor and measuring system. As we reviewed and developed the on-line partial discharge test technique, ceramic coupling sensor, measuring system, terminal box and index parameters.

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.181-190
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• 2007

The phylogenie relationships existing among 14 parasitic Platyhelminthes in the Republic of Korea were investigated via the use of the partial 28S ribosomal DNA (rDNA) D1 region and the partial mitochondrial cytochrome c oxidase subunit 1 (mCOI) DNA sequences. The nucleotide sequences were analyzed by length, G + C %, nucleotide differences and gaps in order to determine the analyzed phylogenie relationships. The phylogenie patterns of the 28S rDNA D1 and mCOI regions were closely related within the same class and order as analyzed by the PAUP 4.0 program, with the exception of a few species. These findings indicate that the 28S rDNA gene sequence is more highly conserved than are the mCOI gene sequences. The 28S rDNA gene may prove useful in studies of the systematics and population genetic structures of parasitic Platyhelminthes.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.553-556
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• 2004

In this study we have performed ab initio computer simulations to investigate the conformational characteristics of the tetraethyl (1) and triethyl ester (2) of p-tert-butylcalix[4]arene. The structures of different conformational isomers for each compound have been optimized using ab initio RHF/6-31G methods. After optimization, B3LYP/6-31+G(d,p) single point calculations of the final structures are done to include the effect of electron correlation and the basis set with diffuse function and polarization function. Relative stability of tetraethyl ester (1) of p-tert-butylcalix[4]arene is in following order: cone (most stable) > partial cone > 1,3- alternate > 1,2-alternate isomer. Relative stability of triethyl ester (2) of p-tert-butylcalix[4]arene is in following order: cone (most stable) > 2-partial cone > 1-partial cone > 3-partial cone ~ 1,3-alternate ~ 1,2- alternate isomer.

• 한국안전학회지
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• 제24권2호
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• pp.30-36
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• 2009

This paper aims at the precursor analysis and DB development of electrical fires based on thermal and current signals for partial disconnection and poor contact on electric wires through experiments and simulations. Also, DB system required for developing the precursor DB with these data was studied and designed. Firstly, in case of partial disconnection, characteristics were derived and analyzed by experiment and electrical-thermal finite element method(Flux 3D) on the model wires which consist of VCTF and IV electric wires. Based on the characteristics, About 351 partial disconnection precursor patterns were generated by the thermal analysis for electric wire according to deterioration time under normal state and 200% overload state of rated current. Secondly, in order to develop poor contact precursor patterns, temperature value and the current signal were considered. In simulating the poor contact situation on connector area of MCCB, connection torque was changed. Through the experimental analysis, about 251 poor contact precursor patterns were generated. Finally, Using thermal precursor patterns obtained by partial disconnection and poor contact, electrical fire thermal precursor DB was developed.

• Kyungpook Mathematical Journal
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• 제47권2호
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• pp.191-202
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• 2007

By using the weighted averaging techniques, we establish oscillation criteria for the second order damped quasilinear elliptic differential equation $$\sum_{i,j=1}^{N}D_i(a_{ij}(x){\parallel}Dy{\parallel}^{p-2}D_jy)+{\langle}b(x),\;{\parallel}Dy{\parallel}^{p-2}Dy{\rangle}+c(x)f(y)=0,\;p>1$$. The obtained theorems include and improve some existing ones for the undamped halflinear partial differential equation and the semilinear elliptic equation.

• Steel and Composite Structures
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• 제45권5호
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• pp.621-640
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• 2022

In the present article, the vibration response of a geometrically imperfect bi-directional functionally graded plate (2D-FGP) with geometric discontinuities and micro-structural defects (porosities) has been investigated. A porosity model has been developed to incorporate the effective material properties of the bi-directional FGP which varies in two directions i.e. along the axial and transverse direction. The geometric discontinuity is also introduced in the plate in the form of a circular cut-out at the center of the plate. The structural kinematic formulation is based on the non-polynomial trigonometric higher-order shear deformation theory (HSDT). Finite element formulation is done using C° continuous Lagrangian quadrilateral four-noded element with seven degrees of freedom per node. The equations of motion have been derived using a variational approach. Convergence and validation studies have been documented to confirm the accuracy and efficiency of the present formulation. A detailed investigation study has been done to evaluate the influence of the circular cut-out, geometric imperfection, porosity inclusions, partial supports, volume fraction indexes (along with the thickness and length), and geometrical configurations on the vibration response of 2D-FGP. It is concluded that after a particular cut-out dimension, the vibration response of the 2D FGP exhibits non-monotonic behavior.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.837-845
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• 2009

We have performed DFT calculations to investigate the conformational characteristics and hydrogen bonds of the calix[6]arene (1) and p-tert-butylcalix[6]arene (2). The structures of various conformers of 1 were optimized by using the B3LYP/6-31G(d,p) and /6-31+G(d,p) methods followed by single point calculation of MPW1PW91/ 6-31G(d,p). The relative stability of the conformers of 1 is in the following order: cone (pinched: most stable) > partial-cone > cone (winged) $\sim$ 1,2-alternate $\sim$ 1,2,3-alternate > 1,4-alternate > 1,3-alternate > 1,3,5-alternate. The structures of different conformers of 2 were optimized by using the B3LYP/6-31G(d,p) method followed by single point calculation of MPW1PW91/6-31G(d,p). The relative stability of the conformers of 2 is in the following order: cone (pinched) > 1,2-alternate > cone (winged) > 1,4-alternate $\sim$ partial-cone > 1,2,3-alternate > 1,3,5alternate > 1,3-alternate. One of the important factors affecting the relative stabilities of the various conformers of the 1 and 2 is the number and strength of the intramolecular hydrogen bonds.

• 한국의류학회지
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• 제20권4호
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• pp.565-572
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• 1996

The purpose of this study was to measure partial heat resistance of Hanbok when it worn. Since Hanbok varies from season to season, four different set of Hanboks (R, SN, p and S) were tested. Also Durumagi (D) which is worn over Hanbok (5) to keep warm from winter cold was tested as well. The thermal manikin was used in this experiment. The room temperature, air velocity and the relative humidity was set at $20\pm0.5^{\circ}C$, 0.15 m/sec and $50\pm$5% respectively. The mean skin temperature of the manikin was set at $33\pm0.5^{\circ}C$. The results were as follows: 1. The order from the least total heat resistance to the most was SN, R, p, 5 and D. 2. Upper arms had the highest heat resistance among the 13 parts. The next was abdomen thighs, buttock, legs, forearms and chest, back, and head, the order from the most to the least.