• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3671-3676
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• 2013

A series of carbon nanotube, $C_{60}$, and graphene modified $TiO_2$ nanocomposites were prepared by hydrothermal method. X-ray diffraction, $N_2$ adsorption, UV-Vis spectroscopy, photoluminescence, and Electrochemical impedance spectra were used to characterize the prepared composite materials The results reveal that incorporating $TiO_2$ with carbon materials can extend the adsorption edge of all the $TiO_2$-carbon nanocomposites to the visible light region. The photocatalytic activities were tested in the degradation of 2,4,6-trichlorophenol (TCP) under visible light. No obvious difference in essence was observed in structural and optical properties among three series of carbon modified $TiO_2$ nanocomposites. Three series of carbon materials modified $TiO_2$ composites follow the analogous tentative reaction mechanism for TCP degradation. GR modified $TiO_2$ nanocomposite exhibits the strongest interaction and the most effective interfacial charge transfer among three carbon materials, thus shows the highest electron-hole separation rate, leading to the highest photocatalytic activity and stability.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.6
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• pp.466-472
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• 2010

Introduction: This study examined the effect of recombinant human bone morphogenetic protein (rhBMP)-2 and $\beta$-tricalcium phosphate ($\beta$-TCP) on new bone formation in a rabbit calvarium using a rapid prototype titanium cap (RP Ti cap). Materials and Methods: Eight New Zealand white rabbits were used in this study. Hemispherical RP Ti caps (10 mm in diameter) were implanted subperiosteally on the rabbit calvaria. $\beta$-TCP was filled in the RP Ti cap in the control group, and rhBMP-2 soaked $\beta$-TCP was used in experimental group. The rabbits were sacrificed 2 and 4 weeks after the operation. The volume and pattern of newly formed bone was analyzed by micro computed tomography (CT). Results: Macroscopically, there were no abnormal findings in any of the animals. The micro CT images revealed new bone from the calvaria that expanded gradually toward the top of the titanium cap, particularly along the inner surface of the titanium cap in the experimental group at 4 weeks after grafting. There was no significant difference in new bone volume ratio between the control and experimental groups at 2 weeks after grafting. There was a statistically significant difference in the new bone volume ratio between the experimental ($14.1{\pm}1.8\;%$) and control ($7.2{\pm}1.5\;%$) groups at 4 weeks after grafting (P<0.01). Conclusion: The RP Ti cap can effectively guide new bone formation and rhBMP-2 can induce the new bone formation.

• Korean Journal of Acupuncture
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• v.28 no.3
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• pp.85-98
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• 2011

Objectives : The aim of this thesis is to examine the effect of acupuncture treatment at the GB37 on normal humans by using the power spectral analysis of the EEG. Methods : EEG (Electroencephalogram) power spectrum exhibits site-specific and state-related differences in specific frequency bands. In this thesis, the power spectrum was measured by the complexity. the 32 channels EEG study was carried out in the 13 subjects (12 males ; age=22.58 years old, 1 females ; 22 years old). Results : In the ${\alpha}$ (alpha) band, the power values at F7, F3, F4, F8, FTC2, C4, T4, CP1, CP2, TCP2, TT2, Pz, P4, Po1, Po2, O1, Oz, O2 channels (p<0.05) during the GB37-acupoint treatment were significantly changed. And in many channels were decreased. In the ${\beta}$ (beta) band, the power values at Cz, C4, T4, Tcp1, T6, Po1, O1, Oz, O2 channels (p<0.05) during the GB37-acupoint treatment were significantly changed. And in many channels were decreased. In the ${\delta}$(delta) band, the power values at Fp1, TT2 channels (p<0.05) during the GB37-acupoint treatment were significantly changed. And in many channels were decreased. In the $\theta$ (theta) band, the power values at Fp1, F8, FTC2, Pz channels (p<0.05) during the GB37-acupoint treatment were significantly changed. And in many channels were decreased. Conclusions : This results suggest that the acupuncture treatment at the GB37 significantly mostly change the power spectrum value on the alpha (18 channels), beta (9 channels) bands.

• Elastomers and Composites
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• v.37 no.4
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• pp.224-233
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• 2002

This study has investigated the flame retardant properties of EPDM rubber with the addition of various flame retardants. Carbon black, stearic acid, zinc oxide cross-linking agent were mixed with EPDM rubber to produce the base rubber E0 without the addition of flame retardants. Phosphorus flame retardant Tricrecyl phosphate(TCP) was added to E0 in 0.5, 1, 1.5, 2 phr to make E1~E4 samples and red phosphorus was added in 3, 6, 9, 12 phr to make E5~E8 samples. A flame retardant of the bromine family Decabromodiphenyloxide(DBDPO), and a chlorinated paraffin retardant of the chlorine family was added to E0 in 3, 6, 9, 12 phr to make E9~E12 and E13~E16 samples, repectively. Basic physical properties such as tensile strength, tear strength and hardness were measured for all the rubber samples with various flame retardant additions. There was no substantial differences. On the other hand, Oxygen index and UL94 were measured to study flame retardant properties. From oxygen index measurements E0 sample showed a value of 23.5%, indicating the improvement of flame retardant properties. Also from UL94 measurements, it was found that addition of red phosphorus resulted in maximum flame retardant effect. It was found that increasing the amount of addition resulted in decreasing combustion rate and improving flame retardant effect regardless of the kind of flame retardant.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1183-1190
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• 2018

The environmental regulations are being strengthened all over the world, and the introduction of electric vehicles are actively being considered to cope with them effectively. It is essential to establish a charging infrastructure, which is an essential element of electric vehicle distribution. In this paper, power line communication technology essential for smart charging infrastructure is studied. A control board capable of achieving a physical layer speed of 10Mbps and a TCP/IP layer of 4.5Mbps, which conforms to the ISO/IEC 15118 international standard, and a control board mounted on the board and compliant with international standards. We have developed a software solution to perform functions for linking. In addition, in order to be applied to the combo-type DC fast charger, the hardware was designed to meet the industrial environment standard and the V2G communication module was developed by integrating it with the software solution.

• Journal of Broadcast Engineering
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• v.6 no.3
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• pp.205-214
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• 2001

In this Paper, we present an MP4 file streaming system over IP networks. Using the proposed system a user can access MP4 contents in the servers via H) networks and interact with the contents. The MP4 file format is designed to contain the media information of MPEG-4 and is object-oriented. The presented streaming server system contains GUI, session manager, splitter, SL- packetizer and transmitter. In addition, we knave implemented the client system based on the GUI -2D player, the MPEG-4 reference software. The Presented streaming system is designed use RTF for the media data requiring real-time streaming RTCP for QoS management and TCP for the data such as IOD(Initial Object Descriptor), OD(Object Descriptor) BIFS(Binary Format for Scene), which should be transmitted for the streaming and the data, such as still image and text, which can be entirely transmitted in a packet.

• Korean Journal of Acupuncture
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• v.20 no.3
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• pp.49-60
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• 2003

The aim of this study was to examine the effects of electroacupuncture(EA) at the PC6 (Naegwan) on normal humans using KarhunenLoeve decomposition method. Electroencephalogram(EEG) is a multi-scaled signal consisting of several components of time series with different dominant frequency ranges and different origins. EEG KarhunenLoeve decomposition method exibit site-specific and state-related differences in specific frequency bands. In this study, KarhunenLoeve decomposition method was used as a measure(D2) of complexity. 30 channel EEG study was carried out in 10 subjects (10 males; $age=21.4{\pm}0.5$ years). Results : We found that the average values and standard deviations of D2 at FP1, FP2, FTC1, FTC2, TT1, TT2, T4, TCP1, P3, P4, T6, OZ channel (p<0.05) were higher than during the acupuncture treatment, and the average values and standard deviations of D2 at F3, F8 channels(p<0.05) were lowered than during the acupuncture treatment. However, the comparison with that before and after the treatment shows no significant differences in all channels.

• Journal of KIISE:Information Networking
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• v.34 no.1
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• pp.16-26
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• 2007

It is well known that, in the near future, the lifetime of the IPv4 address space will be limited and available 32-bit IP network addresses will not be left my more. In order to solve such IPv4 address space problem in an effective way, the transition to the new version using IPv6 architecture is inevitably required. This paper presents the design and implementation of IPv4/IPv6 dual stack at the GSM Phone based on Linux Kernel 2.4 IPv6 Protocol Stack. It designs appropriately in GSM Phone environment and it is tested by a network of Linux IPv4/IPv6 dual stack on PPP. The test was processed with a test scenario and it was found that the results were successful.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1141-1149
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• 2014

The present study was conducted to investigate a supplemental effect of magnesium hydrogen phosphate (MHP, $MgHPO_4$) as an alternative phosphorus (P) source on growth and feed utilization of juvenile far eastern catfish (Silurus asotus) in comparison with three conventional P additives (monocalcium phosphate (MCP), dicalcium phosphate (DCP) and tricalcium phosphate [TCP]) as positive controls. A basal diet as a negative control was prepared without P supplementation and four supplemental P sources were added at the level of 2%. Five groups of 450 fish having mean body weight of 11.3 g following 24 h fasting after three week adaptation period were randomly distributed into each of 15 tanks (30 fish/tank). Fish were hand-fed to apparent satiety twice a day for 8 weeks. Fish fed MHP had weight gain (WG), protein efficiency ratio and specific growth rate comparable to those fed MCP. Fish fed MHP and MCP had feed efficiency (FE) significantly higher (p<0.05) than those fed DCP. Fish groups fed control and TCP showed the lower FE than the other groups which was significantly different (p<0.05) from those of fish fed the other diets. Survival rate was not significantly different (p>0.05) among treatments. Fish fed control had the lowest hematocrit, which was significantly different (p<0.05) from that of fish fed MHP. Fish fed MCP and MHP had plasma P higher (p<0.05) than fish fed the other diets. Relative efficiencies of MCP, DCP and TCP to MHP were found to be 100.5 and 101.3%, 92.0 and 91.6%, and 79.1 and 80.9% for WG and FE, respectively. P availability was determined to be 88.1%, 75.2%, 8.7%, and 90.9% for MCP, DCP, TCP, and MHP, respectively. Consequently, MHP recovered from wastewater stream showed that as an alternative P source its performance was comparative with MCP on growth and feed utilization of juvenile far eastern catfish.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.2
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• pp.92-98
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• 2012

The co-precipitation technique has been applied to synthesize biphasic calcium phosphate (BCP). $Ca(NO_3)_2{\cdot}4H_2O$, $(NH_4)_2HPO_4$, TEOS and $Mg(NO_3)_2{\cdot}6H_2O$ as the starting materials was used. After the heat treatment of powder crystalline phases HAp and ${\beta}$-TCP analysis showed a mixed phase. The overall spectra appear to have mainly two modes corresponding to characteristic $PO^{3-}_4$ and $OH^-$ groups. After immersion in Hanks' Balanced Salt Solution (HBSS) for 1 week a precipitation started to be formed with individual small granules on the specimen surface. An MTT assay indicated that ionic substituted BCP powders had no cytotoxic effects on MG-63 cells, and that they have good biocompatibility.