• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.4
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• pp.59-71
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• 1994

A multi-polynomial method is proposed to synthesize DRRD cam profiles. A cam lift duration s divided into 10 sections, each of them is expressed by a polynomial equation. 12 design variables are extracted from the cam profile displacement, velocity, and acceleration curves. Because all the design variables have physical meanings which are familiar to most cam designers, it is easy to imagine a profile shape from the design variables. The design envelope of the method is wide enough to be used in DRRD automotive cam designs. Polydyne cams, widely used in automotive engines, are included into the envelope. Unlike Polydyne cams, the method provides capability of wide velocity factor variations, which gives much flexibility in flat-faced tappet design. Area factor of profiles designed by the method can be increased 5-10% compared to those of Polydyne cams without increasing acceleration factor. The method is especially useful for cam profile optimizations.

• Journal of Powder Materials
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• v.6 no.2
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• pp.139-144
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• 1999

The pure Ti, Ni and carbon powders were reaction milled to synthesize the TiC-Ni based cermet powders with ultrafine microstructures. After milling, the ultrafine TiC or amorphous Ti-Ni phase was obtained, respectively, according to the milling condition. The effects of milling variables on the synthesizing behavior of the powders were investigated in detail. The sintered TiC-Ni based cermet of the reaction milled powders consisted of very fine TiC of 0.2~1.5$\mu$m, as compared with that of a commercial cermet of 3~5$\mu$m. This demonstrates the potenial of reaction milling as an effective processing route for the preparation of cermet materials.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.14-17
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• 2012

Submicron silver particles were synthesized by chemical reduction with various room temperature ionic liquids. The size and distribution of silver particles were significantly affected by the anion type of ionic liquids and this is mainly attributed to the different abilities of the anions to coordinate with the silver particle, leading to various coagulation of silver particles. Among ionic liquids, 1-butyl-3-methylimidazolium hexafluorophosphate was the most effective to synthesize submicron silver particles.

• Journal of the Korean Society for Library and Information Science
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• v.28
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• pp.193-245
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• 1995

New curriculum for information and library science is proposed on the notion of the internship and scholarly characteristics. The future of the information and library science is expected as the discipline to synthesize the natural science and the social science. Especially the internship is strongly suggested as the post graduate program. To draw the conclusion. the history of the information and library science and its educational background are analyzed. The states of the historical developments of the information and library science are explained in terms of philosophy. The functional and scholarly environments of the information and library science are also investigated. Secondarily it concludes that the curriculum development for information and library science is not aimed on the skills but on the phenomena.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10c
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• pp.409-414
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• 2007

Active Appearance Model is a well-known model that can represent a non-rigid object effectively. However, since it uses the fixed appearance model, the fitting results are often unsatisfactory when the imaging condition of the target image is different from that of training images. To alleviate this problem, incremental AAM was proposed which updates its appearance bases in an on-line manner. However, it cannot deal with the sudden changes of illumination. To overcome this, we propose a novel scheme to update the appearance bases. When a new person appears in the input image, we synthesize illuminated images of that person and update the appearance bases of AAM using it. Since we update the appearance bases using synthesized illuminated images in advance, the AAM can fit their model to a target image well when the illumination changes drastically. The experimental results show that our proposed algorithm improves the fitting performance over both the incremental AAM and the original AAM.

• Textile Coloration and Finishing
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• v.19 no.6
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• pp.35-38
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• 2007

FTriphenylamine dye compound having diheteryl moiety was synthesized and its photoluminescent property was investigated. Organic luminescent materials have received great attentions due to potential application subjects onto full color image displays. In this context, the dye (III) for light emitting materials was synthesized using 2-(4-amino-2-hydroxyphenyl)benzoxazole (I) and 4,4'-diformyltriphenylamine (II). It is well known that the amino groups of compound (I) react with carbonyl groups, especially an aldehyde, to afford azomethine linkages. The dye shows bulish-green fluorescence property, which is anticipated for the light-emitting material for display devices. In this context, our aim is to synthesize diheteryl-substituted triphenylamine fluorescent dye as an emitting material. The spectroscopic characteristics and the fluorescent properties of this dye molecule were examined and determined.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.4
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• pp.537-547
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• 2015

A Monte Carlo (MC) simulation was conducted to predict the reliability of a newly developed pyrotechnic pin puller. The reliability model is based on the stress-strength interference model that states that failure occurs if the stress exceeds the strength. In this study, the stress is considered to be the energy consumed by movement of a pin shaft, and the strength is considered to be the energy generated by pyrotechnic combustion for driving the pin shaft. Failure of the pin puller can thus be defined as the consumed energy being greater than the generated energy. These energies were calculated using a performance model formulated in the previous study of the present authors. The MC method was used to synthesize the probability densities of the two energies and evaluate the reliability of the pin puller. From a probabilistic perspective, the calculated reliability was compared to a deterministic safety factor. A sensitivity analysis was also conducted to determine which design parameters most affect the reliability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.87-88
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• 2018

The change in the degree of powder in cement is very important because it plays a major role in the reaction in the concrete. In this study, we intend to apply the principle of early estimation of concrete strength using the non-middling method previously conducted to the quality evaluation of cement powder. In other words, it is proposed to analyze the potential of Hydrometer density values and the data of temperature variation in the trust solution to propose a method of acceptance inspection. According to the experimental results, the quick evaluation of the cement distributorship will be possible if the resulting regression results are used : y = 161867.4 x₁ + 117.953 x₂ - 165437 (R = 0.9158).

• Journal of Family Resource Management and Policy Review
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• v.19 no.3
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• pp.1-16
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• 2015

The purpose of this study was to synthesize the results of studies on the effects of multi-cultural education program for Korean children. Using the author's own selection criteria, 17 studies were finally selected and 31 effect sizes were calculated from these studies and used for meta analysis. The overall effect size for all studies on the random effect model was .802, and it was positive and high. Given the heterogeneity among the effect size, subgroup analysis was conducted. According to the analysis, effect sizes significantly differed depending on program goal, concerned multi-cultural higher than others. Result also showed that the high scored effect sizes were the general family, pre-school age children group, and the program were 11-20 children group in size, and 11~20 times in frequency of education.

• Ceramist
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• v.21 no.2
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• pp.29-37
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• 2018

In order to overcome the problems of existing low-dimensional materials (carbon nanotubes, graphene, transition metal dichalcogenides, etc) researches on new 1D materials have been studied. In the case of $LiMo_3Se_3$ and $Mo_6S_{9-x}I_x$, continuous researches have been carried out for 3D bulk synthesis and atomic scale dispersion. Recently, quantum confinement effect of $LiMo_3Se_3$ and bio-stability of $Mo_6S_{9-x}I_x$ have been proven and various applications have started to be studied. In addition, device application results using new 1D materials such as $Sb_2Se_3$ (optoelectronic devices using the property of effectively reducing exciton decay due to no dangling bond) and $VS_4$ (electrochemical energy storage using the space between 1-D nanostructures) have been reported very importantly. Therefore, it can be claimed that it has reached a very important time to find and synthesize new 1D materials and to report various characteristics not existing.