• The Korean Journal of Nuclear Medicine
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• v.20 no.2
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• pp.39-45
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• 1986

Resting gated blood pool scan was used to derive left ventricular functional changes in normals (N=13, mean age=43) and in patients with coronary artery disease (N=50, mean age=53). Peak filling rates, average filling rates, and ejection fractions were significantly depressed in coronary artery disease. (p<0.0005, each other). And in coronary artery disease with normal ejection fraction (N=21), peak filling rates and average filling rates were depressed also, and peak filling rates of coronary artery disease with normal ejection fraction were abnormal in 61.2% and average fillin rates were abnormal in 71.4%. It appears that (1) resting peak filling rates and average filling rates were sensitive and easily obtainable parameters of the diastolic dysfunction assosiated with coronary artery disease, (2) a significant proportion of coronary artery disease patients without any evidence of abnormal systolic function have depressed resting peak filling rates and average filling rates of the left ventricle.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.5
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• pp.657-665
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• 2003

Several interesting results were obtained from the flow visualization experiment in the accompanying paper, Part I. in the present study, Part II, a numerical study has been carried out to explain the detailed flow phenomena in micro-channel filling process. Hele-Shaw flow approximation was applied to the micro-channel geometry based on the small characteristic length. And surface tension effect has been introduced on the flow front as the boundary condition with the help of a dynamic contact angle concept between the melt front and the wall. A dimensional analysis for numerical results was carried out and a strong relationship between dimensionless pressure and Capillary number is obtained. The numerical analysis results are compared with the flow visualization experimental observations. And the numerical system developed in the present study seems to be able to predict the interesting micro-channel filling flow characteristics observed from experiments.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.843-847
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• 2014

In Super Junction (SJ) MOSFETs, charge balance is the most important issue of the SJ fabrication process. In order to achieve the best electrical characteristics, such as breakdown voltage and on-resistance, the N-type and P-type drift regions must be fully depleted when the drain bias approaches the breakdown voltage, which is known as the charge balance condition. In conventional charge balance analysis, based on multi-epi process SJ MOSFETs, analytical model has only N, P pillar width and doping concentration parameter. But applying a conventional charge balance principle to trench filling process, easier than Multi-epi process, is impossible due to the missing of the trench angle parameter. To achieve much more superior characteristics of on-resistance in trench filling SJ MOFET, the appropriate trench angle is necessary. So in this paper, modulated charge balance analysis is proposed, in which a trench angle parameter is added. The proposed method is validated using the TCAD simulation tool.

• Restorative Dentistry and Endodontics
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• v.12 no.1
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• pp.149-153
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• 1986

Clinical analysis on early evidence of the pulp response to composite resin filling (27 cases) was made and reached to the results as follow; 1. Under age 40's early symptome was reported within the 1st, 2nd, 3rd and 4th week after composite filling evenly and age 50's reported after 4th week. 2. Sensitive response to cold were 11 cases, to warm 3 cases and to both (cold, warm) were 9 cases. 3. Tenderness to percussion and light pressure on apical area were 5 cases.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.1838-1843
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• 2014

Nanoimprint lithography (NIL) fabrication process is regarded as the main alternative to existing expensive photo-lithography in areas such as micro- and nano-electronics including optical components and sensors, as well as the solar cell and display device industries. Functional patterns, including anti-reflective moth-eye pattern, photonic crystal pattern, fabricated by NIL can improve the overall efficiency of such devices. To successfully imprint a nano-sized pattern, the process conditions such as temperature, pressure, and time should be appropriately selected. In this paper, a cavity-filling process of the moth-eye pattern during the thermal-NIL within the temperature range, where the polymer resist shows the viscoelastic behaviors with consideration of stress relaxation effect of the polymer, were investigated with three-dimensional finite element analysis. The effects of initial thickness of polymer resist and imprinting pressure on cavity-filling process has been discussed. From the analysis results it was found that the cavity filling can be completed within 100 s, under the pressure of more than 4 MPa.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2364-2369
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• 2015

In this paper, the optimum RPM was suggested comparing rotor filling rate of RPM through the analysis of rotor's filling rate as studying and developing centrifugal-casting machine's method for high precision rotor in order to increase the related types of business's productivity. The result was similar to other result in industrial site, showing 99.47% of filling rate when rotational speeds are 600 rpm, so it is considered that if this result is conducted with additional research, it will be possible to plan a better process design. Besides, the optimum temperature of compact ladle was examined to produce high quality casting product through the analysis of compact ladle's conductivity. In the case of the heating device's absence using nicrome wire, Al solution solidifies falling drastically into $427^{\circ}C$. However, it is feasible to work over $427^{\circ}C$ which is the melting temperature of aluminium solution when the heating device of nicrome wire is included. It reveals that there is little temperature change.

• Tunnel and Underground Space
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• v.24 no.6
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• pp.449-463
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• 2014

There are many case studies and application cases in abandoned mines for hydraulic filling method filled by slurry or paste form, but research on the pneumatic filling is not applied in Korea. The damage of steel pipe is occurred by wear due to the flow of filling material in the bent area of steel pipe in traditional pneumatic filling method. In this study, the new pneumatic filling method was developed using a newly devised improved nozzle to improve the above problem. The model test for mine filling was performed in the laboratory for the simulated accessible or inaccessible mine cavities, and the filling efficiency by the results obtained from the test was calculated. The filling efficiency was analyzed from the variation of outlet angle, feed rate and grain size of sand in model test of simulated accessible mine cavity. The superiority of improved pneumatic filling method was proved through the analysis of filling efficiency by the results obtained from each model tests of gravitational, traditional, and improved filling method in simulated inaccessible mine cavity.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.4
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• pp.21-27
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• 2014

The injection molding process has several advantages enabling it to produce large quantities of molded plastic products using a repetitive process. In recent years, it has been necessary to develop an injection molding process with micro/nano-sized patterns for application to the semiconductor industry and to the bio/nano manufacturing industry. In this study, we apply gas pressure to the inside of a mold and consider the gas dissolution phenomenon for a resin filling into a micro pattern with a line structure. Using numerical analysis, we calculate the filling ratio with respect to time for various internal gas pressures and various aspect ratios of the micro-patterns.

• Journal of Welding and Joining
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• v.32 no.3
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• pp.11-18
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• 2014

TSV(through silicon via) filling technology is making a hole in Si wafer and electrically connecting technique between front and back of Si die by filling with conductive metal. This technology allows that a three-dimensionally connected Si die can make without a large number of wire-bonding. These TSV technologies require various engineering skills such as forming a via hole, forming a functional thin film, filling a conductive metal, polishing a wafer, chip stacking and TSV reliability analysis. This paper addresses the TSV filling using Cu electrodeposition. The impact of plating conditions with additives and current density on electrodeposition will be considered. There are additives such as accelerator, inhibitor, leveler, etc. suitably controlling the amount of the additive is important. Also, in order to fill conductive material in whole TSV hole, current wave forms such as PR(pulse reverse), PPR(periodic pulse reverse) are used. This study about semiconductor packaging will be able to contribute to the commercialization of 3D TSV technology.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.1
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• pp.26-32
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• 2012

In the present study, the stencil printing process using solder paste are numerically analyzed. The key design parameters in the stencil printing process are the printing conditions, stencil design, and solder paste properties. Among these parameters, the effects of printing conditions including the squeegee angle and squeegee pressure are investigated through finite element (FE) analysis. However, the FE analysis for the stencil printing process requires tremendous computational loads and time because this process carries micro-filling through thousands of micro-apertures in stencil. To overcome this difficulty in simulation, the present study proposes a two-step approach to sequentially perform the global domain analysis and the local domain analysis. That is, the pressure development under the squeegee are firstly calculated in the full analysis domain through the global analysis. The filling stage of the solder paste into a micro-aperture is then analyzed in the local analysis domain based on the results of the preceding global analysis.