• The Journal of the Korean dental association
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• v.56 no.10
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• pp.567-571
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• 2018

Obturation is a important procedure of root canal treatment. Canal filling should be both provide a hermetic seal for the root canal system and eliminate leakage channel from the oral cavity. Gutta-percha have been the standard material of choice for root canal obturation. Canal filling has been aimed at maximizing the amount of gutta-percha and minimizing the amount of sealer. However recently, single cone technique has been introduced that include calcium silicate-based sealer and single gutta-percha cone. It is important to select an obturation technique that offers consistency and is easy to use. From the standpoint of appropriate technology, the single cone technique is thought to be useful for general dentist.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2016.11a
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• pp.124.1-124.1
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• 2016

In this work, uniform thickness and good adhesion of electrodeposited copper layer were achieved on AZ91 Mg alloy in alkaline noncyanide copper solution containing pyrophosphate ion by employing appropriate zincate pretreatment. Without zincate pretreatment, the electrodeposited copper layer on AZ91 Mg alloy was porous and showed poor adhesion which was explained by small number of nucleation sites of copper due to rapid dissolution of the magnesium substrate in the pyrophosphate solution. The zincate pretreatment was found as one of the most important steps that can form a conducting layer to cover AZ91 surface which decreased the dissolution rate of AZ91 Mg alloy about 40 times in the copper pyrophosphate solution. Electrodeposited copper layer on AZ91 Mg alloy after an appropriate zincate pretreatment showed good adhesion and uniform thickness with bright surface appearance, independent of the deposition time but the surface roughness of the electrodeposited copper layer increased with increasing Cu deposition time.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2001.01a
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• pp.219-223
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• 2001

Within a mechanical system such as an automotive the number of standard machine parts is increasing, so that the parts selection becomes more important than ever before. Selection of appropriate bearings in the preliminary design phase of a machine is also important. In this paper, three decision-making approaches are compared to find out a model that is appropriate to bearing selection problem. An artificial neural network, which is trained with real design cases, is used to select a bearing mechanism at the first step. Then, the subtype of the bearing is selected by the weighting factor method. Finally, types of peripherals such as lubrication methods are determined by a rule-based expert system.

• Knowledge Management Research
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• v.11 no.1
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• pp.37-50
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• 2010

Bioharmaceutical technologies have consistently been areas in which large licensing agreements have been negotiated. However, there are very limited informations in the open literature on how its running royalty rates are determined and no specific methods are yet provided. The purpose of this study is to suggest an appropriate method for the estimation of running royalty of bioharmaceutical technology in licensing agreements. Here distribution of risk-adjusted operating margins are obtained by simulation using statistics of success rates in the stage of clinical trials and profit margins. Three factors based on technology, business and license legal terms are considered and combined as licensing competitiveness level. Finally, reasonable running royalty is estimated by combining simulated distribution and licensing competitiveness level. This suggested method is expected to practically useful for licensor to establish an appropriate running royalty rate for licensing.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.05a
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• pp.20-23
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• 1999

The current three-stage cold extrusion process including upsetting to produce a flange is investigated for the purpose of improvement of manufacturing process. The main goal of this study is to obtain an appropriate process sequence which can produce the required part most economically without overloading of tools and select an appropriate process for reducing manufacturing cost. The current process sequence is simulated and design criteria are examined. Based on the results of simulation of the current three-stage process, a design strategy for improving the process sequence is developed using the thick-wall pipes. Based on the results of simulation of the one-stage processes, the forming processes of a flange for improving the conventional process are proposed.

• Asia pacific journal of information systems
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• v.3 no.1
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• pp.190-213
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• 1993

The information revolution is sweeping through the global economy. Information technology is transforming the structure of competition. The successful implementation of information technology is dependent on the effectiveness of information systems planning. However, it is very difficult to select an appropriate methodology for information systems planning given an organization situation. A contingency model is proposed on the selection of an appropriate approach depending upon the organizational situation. Although the contingency framework is not yet theoretically proved, the approaches suggested here turned out to be of benefit to the cases of the two real world projects studied. These approaches attempt to combine Business Systems Planning of IBM and Critical Success Factors in two different manners to make planning process more efficient and effective.

• Journal of Ocean Engineering and Technology
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• v.11 no.4
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• pp.239-248
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• 1997

The nesting of parts cut on raw steel plate has been a subject of interest to the shipbuilding industry for many years. "Nesting" is defined operation of layout of the parts on the raw material with minimizing the waste rate. Therefore, it is very important to optimize the cutting area. Since the existing nesting programs are prepared for expensive workstations and the expert, it is needed to develop nesting program for personal computer to improve the technology of small/middle sized shipyards and their productivity. This study involves development and application of appropriate optimization technique to solve the problem of plate nesting. And the appropriate D/B for storing nesting data developed, the function of D/B is introduced in this paper.his paper.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.7-12
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• 2009

In JPEG2000, the Cohen-Daubechies-Feauveau (CDF) 9/7-tap wavelet filter adopted in lossy compression is implemented by the lifting scheme or by the convolution scheme while the LeGall 5/3-tap wavelet filter adopted in lossless compression is implemented just by the lifting scheme. However, these filters are not optimal in terms of Peak Signal-to-Noise Ratio (PSNR) values, and irrational coefficients of wavelet filters are complicated. In this paper, we proposed a method to optimize image quality based on wavelet filter design and on wavelet decomposition. First, we propose a design of wavelet filters by selecting the most appropriate rational coefficients of wavelet filters. These filters are shown to have better performance than previous wavelet ones. Then, we choose the most appropriate wavelet decomposition to get the optimal PSNR values of images.

• Journal of Institute of Convergence Technology
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• v.4 no.1
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• pp.33-35
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• 2014

Investigation of flow characteristics behind a edged backward facing step is important for selecting appropriate positions of building constructions in the desert area. In the present study, the effect of edge angles on the flow characteristics is investigated using a commercial software CFD-ACE+. When the edge angle is less than 30 degree, reattachment length decreases, whereas when the edge angle is larger than 30 degrees, reattachment angle increases. It can be concluded that the flow patterns behind an edged backward facing step is classified as the two, streamlined and bluffed bodies. Appropriate edge angles have an effect of increasing the momentum toward the wall, which can reduce the reattachment length. It can be said that present results can be utilized for diverse industrial applications that includes the backward facing step.

• Journal of Science and Technology Studies
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• v.18 no.3
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• pp.45-101
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• 2018

This paper discusses an important dimension of the globalization of science by investigating the lived experiences of nineteen expatriate scientists in six institutions in South Korea. Although much has been written on the globalization and science, few works have dealt with scientific experts? migration across national borders in contemporary contexts. In this regard, the lives of foreign science professors in Korea offer an interesting case, as they illustrate how the ideas of global science both clash with and appropriate Korea?s local practices and discourses. I argue that the globality of science is a main factor that fosters the continued Korean stay of many foreign scientists, who manage and appropriate what is entailed in this globality, namely, Korea?s perceived status as a peripheral country in the dynamics between "center" and "periphery." This includes several strategies and unintended situations differing according to each foreign scientist?s ethnic origins, professional experiences, and institutional circumstances, which lead them to make sense of their continued stay in Korea.