• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.168.2-168.2
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• 2015

We observed the temperature-dependent evolution and behavior of P3HT type-II phase during a real time annealing process from a cryo-cooled low temperature in the absence and presence of an Al electrode. A poly (3-hexylthiophene) (P3HT) Type-II phase in the P3HT:PCBM films started to form near at $-10^{\circ}C$, regardless of Al layer presence. In the absence of an Al layer, type-II phase was extinct at $30^{\circ}C$. However, the extinction temperature was extended to $50^{\circ}C$ in the presence of the Al layer. Simultaneously, combined with the type-II phase, a 1:3 ordered P3HT type-II (1/3,0,0) super-lattice peak evolved. These type-II domains tended to be formed near the Al electrode layer with higher aligned status than host P3HT crystals.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.2
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• pp.216-227
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• 2007

Statement of problem: For the long-term success of removable partial dentures, the bonding between metal framework and denture base resin is one of the important factors. To improve bonding between those, macro-mechanical retentive form that is included metal framework design has been generally used. However it has been known that sealing at the interface between metal framework and denture base resin is very weak, because this method uses mechanical bonding. Purpose: Many studies has been made to find a simple method which induces chemical bond, now various bonding system is applied to clinic. In this experiment, shear bond strengths of heat-cured denture base resin to the surface-treated Co-Cr alloy were measured before and after thermocycling. Chemically treated groups with Alloy $Primer^{TM}$, Super-Bond $C&B^{TM}$, and tribochemically treated group with $Rocatec^{TM}$ system were compared to the beadtreated control group. The data were analyzed with two-way ANOVA. Result: 1. Shear bond strength of bead-treated group is highest, and Alloy $Primer^{TM}$ treated group, Super-Bond $C&B^{TM}$ treated group, RocatecTM system treated group were followed. Statistically significant differences were found in each treated group(p<0.05). 2. Surface treatment and thermocycling affected shear bond strength(p<0.05), however there was no interaction between two factors(p>0.05). 3. Shear bond strengths of bead-treated group and Alloy $Primer^{TM}$ treated group showed no statistically significant difference before and after thermocycling(p>0.05), and those of Super-Bond $C&B^{TM}$ treated group and $Rocatec^{TM}$ system treated group showed statistically significant difference after thermocycling(p<0.05).

• Communications of the Korean Mathematical Society
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• v.23 no.3
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• pp.421-426
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• 2008

Let $M^n$ be a complete immersed super stable minimal submanifold in $\mathbb{R}^{n+p}$ with fiat normal bundle. We prove that if M has finite total $L^2$ norm of its second fundamental form, then M is an affine n-plane. We also prove that any complete immersed super stable minimal submanifold with flat normal bundle has only one end.

• Bulletin of the Korean Mathematical Society
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• v.46 no.6
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• pp.1213-1219
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• 2009

Let M$^n$ be a complete oriented non-compact minimally immersed submanifold in a complete Riemannian manifold N$^{n+p}$ of nonnegative curvature. We prove that if M is super-stable, then there are no non-trivial L$^2$ harmonic one forms on M. This is a generalization of the main result in [8].

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2008.10a
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• pp.77-78
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• 2008

Affinity between alkyl substituted super hydrophobic dyes and polypropylene fiber has been analyzed by using the molecular descriptor as a method to predict chemical and physical characteristics of compounds. Hydrophobicity of synthesized dyes calculated by LogP which is one of molecular descriptors was increased continuously as the length of alkyl substituents increased.

• Journal of the Korean Society of Physical Medicine
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• v.15 no.1
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• pp.33-42
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• 2020

PURPOSE: This study examined the effects of a whole body vibration-exercise program on the muscle strength, balance, and falling efficacy of super-aged women. METHODS: Thirty participants, who are over 75 years of age, were recruited. They were assigned randomly to an experimental group (n=15), which received whole body vibration exercise, and a control group (n=15), which received an exercise program that did not include vibration. The interventions lasted for four weeks, three times a day, and 25 minutes per session. To compare the effects of the intervention, a 30-second chair stand test (CST), Korean version of Berg balance scale (K-BBS), functional reach test (FRT), timed up and go test (TUG), and Korean version of the falls efficacy scale (K-FES) was used. RESULTS: The experimental group showed a significant increase (p.<05) before and after the intervention in the chair stand test (CST), Korean version of the Berg balance scale (K-BBS), functional reach test (FRT), timed up-and-go (TUG), and Korean version of the fall efficacy scale (K-FES). Compared to the control group, the experiment group showed a more significant increase (p.<05) in the CST, K-BBS, and FRT. CONCLUSION: A whole body vibration exercise program could be suggested as an effective intervention method for muscle and balance strengthening for super-aged women.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.3
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• pp.602-612
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• 2015

Current IEEE 802.11p which is suggested for vehicle to vehicle communication supports one hop communication. Thus, it has a limitation to carry out efficient data dissemination. In this thesis, we suggest LTE-D2D based vehicle network to provide efficient data dissemination in the vehicle environment. In this network architecture, we use name based message with IP packet options and we put the intermediate vehicle node called 'super vehicle node' and each normal vehicle node in the cell requests data to the super vehicle node. The super vehicle node responses data to the normal vehicle node. Performance analysis is based mathematical modeling. We compare LTE cellular network to LTE-D2D based vehicle network about throughput according to packet delivery time.

• 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.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.55-63
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• 2003

In this study, an experimental research of grinding characteristics using super-abrasives for surface carburized and heat treated SCM415 materials, which were usually used to make a linear motion guide block and were comparatively hard-to-machine materials, was carried out. In order to conduct a high efficiency and a accuracy grinding of such materials, grinding processes using CBN (Cubic boron nitride) and 38P grinding wheels have been attempted on a surface grinding machine. The grindability according to each grinding conditions was evaluated by means of a grinding force, a surface roughness and a residual stress. The experimental methods and results were presented in this paper. And also, from a proposed truing method the CBN wheels that combined a copper and a break truer gave a full scope to the wheel's performance.

• Journal of the Korean Society for Precision Engineering
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• v.9 no.4
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• pp.147-153
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• 1992

This study was undertaken to investigate the cutting behaviour of super duralumin (A2024-T3) with sintered carbide tool(P20). The cutting test was carried out under different conditions such as cutting speed, cutting depth and rake angle, etc. The specific cutting force Kc and Kt of vertical and radial forces decreases as cutting speed increases, especially the decrease rate of Kt becomes larger than of Kc as cutting speed increases. Kc and Kt in small cutting depth are much affected by work-hardening of surface layer. The chip width and shear angle become layer as cutting depth increases, especially chip width at feed of 0.1mm almost approaches cutting width. Relation between the friction coefficient of chip side and tool rake angle side can make the modelization studying the built-up edge size. The shear angle model equation of super duralumin generally agree with theory of Ernst-Merchant.