• Journal of the Korean Society of Industry Convergence
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• v.21 no.6
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• pp.429-437
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• 2018

The process gas piping of the offshore plant can cause a massive explosion if the gas leakage occurs during operation. For the purpose of precaution of gas leakage accident, an air pressure test is performed on the process equipment tests using a test pump as much as the power to the piping inner side, mix 99% nitrogen gas and 1% helium gas. The purpose of the air pressure test is to check the work conformity process by handling and regulation for initial piping process, assembly, installation of module, welding, center alignment of the pipes assembling flange gasket in an unrestrained free state. In this paper, the regulation of the problematic air pressure test was analyzed and the solution criteria were established. And leakage tests of existing equipment were performed applying these solution methods. As a result, it was confirmed that there was no problem.

• Restorative Dentistry and Endodontics
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• v.18 no.1
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• pp.55-72
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• 1993

The aim of this study was to compare the marginal leakage of class II light curing composite resin restoration according to filling methods. With using acid etching technique and dentin bonding agent, various methods were suggested to eliminate or reduce the marginal leakage. In this study, class II cavities were prepared in 100 extracted human premolars with cementum margin(1mm below the CEJ) and the teeth were randomly assigned to 5 groups of 20 teeth each. The teeth in group 1, 2, 3 and 4 were restored by direct filling methods using P-50 and Clearfil Photoposterior of 10 teeth each, but the method of insertion of the restorative materials varied with each group. And the teeth in group 5 were restored by inlay method using Kulzer Inlay and CR Inlay. Filling methods are as follows : Group 1 : The composite resin was inserted in one layer in the proximal box and one layer in the occlusal portion. Group 2 : Insertion was in two equally thick horizontal layers in the proximal box. Group 3 : Insertion was in two diagonally placed layers in the proximal box. Group 4 : The composite resin was inserted in the same way as in group 3 except that a glass ionomer liner was first placed on the axial wall and gingival floor. Group 5 : The teeth were restored by Inlay technique using dure cure resin cement. All the teeth were thermocycled, stained with 1 % methylene blue solution, sectioned mesiodistally, and scored for marginal leakage. To compare the marginal leakage, ANOVA and T-test were used in analysis. The following results were obtained : 1. In direct filling methods, there was no significant difference in marginal leakage at both occlusal and cervical margins. 2. In all groups, occlusal margin showed significantly less leakage than cervical margin. 3. In group using glass ionomer liner, there was no significant reduction of marginal leakage at the cervical margin. 4. The group restored by inlay method showed significantly less marginal leakage than groups restored by direct filling methods at both occlusal and gingival margins. 5. There was no significant difference in each group according to filling materials.

• Membrane Journal
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• v.4 no.3
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• pp.163-170
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• 1994

The separation of inorganic salt from amino acid solution using was performed electrodialysis. In order to review the availability of electrodialysis using isoelectric point of amino acid as a bio-separation technique, electrodialysis stacks were designed using ion exchange membrane. Separation of NaCl from amino acid solution was performed in the condition similar to amino acid fermentation process. To obtain otimum conditions of separation, leakage of amino acid depending of pH and limiting current density were measured. On the basis of optimum condition, removal of NaCl and leakage of amino acid were investigated quantitatively in batch and continuous process, and current efficiencies were also obtained. As a result of batch experiment for 11 hours each amino acid solution, removal efficiencies of NaCl were in the ranges of 96.1~96.2%. Amino acid leakage rate of glycine, methionine, alanine were 2.5, 1.7, 2.0% respectively. Current efficiencies were in the ranges of 44.5~44.6%. As a result of continuous experiment in various flow rate of each amino acid solution, it took 120 ~ 150 min to reach to steady state. Removal efficiency of NaCl was increased as the flow rate was decreased, but current efficiency was decreased. At the steady states, there were no leakage of amino acid.

• Journal of the Korean Vacuum Society
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• v.19 no.1
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• pp.52-57
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• 2010

$BiFeO_3/Pb(Zr_{0.52}Ti_{0.48})O_3$(BFO/PZT) multilayer thin films have been prepared on a Pt/Ti/$SiO_2$/Si(100) substrate by chemical solution deposition. BFO single layer, BFO/PZT bilayer and multilayer thin films were studied for comparison. X-ray diffraction analysis showed that the crystal structure of all films was multi-orientated perovskite phase without amorphous and impurity phase. The leakage current density at 500 kV/cm was reduced by approximately four and five orders of magnitude by bilayer and multilayer structure films, compared with BFO single layer film. The low leakage current density leads to saturated P-E hysteresis loops of bilayer and multilayer films. In BFO/PZT multlayer film, saturated remanent polarization of $44.3{\mu}C/cm^2$ was obtained at room temperature at 1 kHz with the coercive field($2E_c$) of 681.4 kV/cm.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.1041-1044
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• 1999

This paper propose a solution to resolve data overflow or leakage when a subscriber receive data to service provider. The set-top box can communicate with a service provider and can inform the service provider its data overflow or leakage. When service provider received this control signal, it changes data transmit rate and transmits data with changed rate. The buffer of set-top box is important because incoming data from a service provider are stored by it.

• Tribology and Lubricants
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• v.8 no.2
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• pp.44-49
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• 1992

Hydrodynamic lateral forces acting on circumferentially grooved and tapered pistons in hydraulic piston pumps are analyzed for the case where the axis of piston and cylinder are tilted with each other. The effects of grooves and tilting on lateral force and leakage flowrate are discussed from the analytical solution of one-dimensional Reynolds equation. The analytical solution is in accordance with the numerical solution of two-dimensional Reynolds equation as the number of grooves increases.

• Journal of Chest Surgery
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• v.19 no.2
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• pp.217-224
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• 1986

Using an isolated rat heart preparation under both aerobic and ischemic condition, we observed the myocardial protective effect of verapamil cardioplegia. Isolated working hearts were subjected to global ischemia at 25oC. Before ischemic arrest, rat hearts were treated with cold potassium cardioplegic solution [K=30 mEq/L] in control group and cold potassium cardioplegic solution added with verapamil [1 mg/L] in other group. After 30 min. of ischemia, hemodynamic parameters and creatine kinase leakage in coronary effluent were observed. Verapamil group exhibited greater percent of recovery in aortic pressure [p<0.01], aortic flow [p<0.01], and stroke volume [p<0.05]. Although there were no significant difference in creatine kinase leakage and the percent recovery of cardiac output between verapamil and control group, verapamil group showed better myocardial function. But the time to recover regular sinus rhythm was significantly [p<0.001] prolonged in verapamil group.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.528-534
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• 2001

Basic equations and its solution procedure are derived for the analysis of an annular pump seal in which the rotor has a large static displacement from the centered position. The Bulk-flow is assumed for a control volume set in the seal clearance and the flow is assumed to be completely turbulent in axial and circumferential direction. Moody's wall-friction-factor formula is used for the calculation of wall shear stresses in the control volume. For the reaction force developed by the seal, linearized zeroth-order and first-order perturbation equations are developed for small motion about an eccentric position. Flow variables are expanded by using Fourier series for the solution procedure. Integration of the resultant first-order pressure distribution along and around the seal defines the 12 elements of rotordynamic coefficients of the eccentric annular pump seal. The results of leakage and rotordynamic coefficients are presented and compared with the Marquette's experimental results and the San Andres' theoretical analysis.

• Journal of information and communication convergence engineering
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• v.1 no.2
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• pp.70-73
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• 2003

We have studied the effects of solvents and additives in the precursor solutions on the characteristics of barium strontium titanate (BST) thin films. The solution having two solvents, ie. acetic acid for barium acetate and strontium acetate and 2-methoxyethanol for titanium isopropoxide and also having an additive of ethylene glycol shows good stability and remains homogeneous even after a month of ageing. It produces excellent BST thin film without cracks. Dielectric constant, loss tangent at 10KHz and leakage current density at 3V of the BST (70/30) thin film made from this solution are 339, 0.052 and 13.3 ${\mu}\textrm{A}$/$\texmrm{cm}^2$, respectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.51-56
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• 2005

It does not find for solution by limitation of technological mechanism of existent of leakage maintenance material. So, it is paid for huge expense because continuous repeat maintenance work is consisting. Furthermore, it is indicated by big problem in construction work that is constructed by field experience that thing by definite and systematic theory is not with proper performance test and analysis up to now. Therefore, wish to measure physical performance change by various environment condition maintenance of structure and performance construction work aspect in that apply to water leakage maintenance material using of acrylic resin system water expansion, leakage maintenance material in this research, and present suitable form of construction work under these environment. also, wish to ready diversified remedy by oversea market opening.