• Proceedings of the Korea Information Processing Society Conference
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• 2014.11a
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• pp.171-172
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• 2014

This paper proposes a SDN based Proxy Mobile IPv6 (PMIPv6) architecture for heterogeneous vehicular networks (SDN-VANET), to provide the continuity of service during the horizontal handovers and to reduce the delay during vertical and horizontal handovers. SDN-VANET mainly relies on DSRC road side units (RSUs) for V2I communication and to overcome the coverage problem SDN-VANET performs the vertical handover between DSRC and LTE/UMTS. To date there is no standard to perform network layer vertical handovers. Therefore the proposed SDN-VANET architecture also doesn't provide any mechanism for vertical network layer handovers, but solves the horizontal network layer handovers in DSRC or LTE/UMTS through introducing PMIPv6 in the architecture.

• Progress in Superconductivity
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• v.3 no.1
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• pp.1-4
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• 2001

Interface-engineered junctions with $YbBa_2$$Cu_3$$O_{7}$ as the counter electrode were demonstrated. The junctions exhibited excellent Josephson characteristics with a Josephson critical current ($I_{c}$) ranging from 0.1 mA to 8 mA and a magnetic field modulation of the $I_{c}$ exceeding 80% at 4.2 K while maintaining complete c-axis orientation of the counter-electrode layer. The$ 1\sigma$ spreads in $I_{c}$ for junctions with an average $I_{c}$ of 1-2 mA were 5-8% for 16 junctions within a chip, and 9.3% for a 100-junction array. Our dI/dV measurements suggest that a theoretical approach taking into account both a highly transparent barrier and the proximity effect is required to fully understand the Junction characteristics.ristics.

• Asia pacific journal of information systems
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• v.30 no.1
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• pp.94-119
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• 2020

Digital platforms characterized by network effects enable provisioning of various types of services and provide a mechanism for linking producers and consumers. Identifying the key Quality of Service attributes of such platforms is vital for their continued success and growth. In this paper, a set of quality attributes for platforms is first extracted from different extant quality models. Then actual user feedback data from three platform providers are analysed and mapped against the set of quality attributes to determine the key attributes that are relevant. These findings are corroborated with qualitative data from interviews of different stakeholders. The results show that service quality characteristics are important to the success of platforms. Functional characteristics of platforms assume importance where the digital contributions of the platform is higher. Apart from these, 'fitness for use' as a major determinant of quality is also important in digital platforms.

• Fisheries and Aquatic Sciences
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• v.22 no.12
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• pp.30.1-30.11
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• 2019

Marine natural products isolated from the sponge Fascaplysinopsis cf reticulata, in French Polynesia, were investigated as an alternative to antibiotics to control pathogens in aquaculture. The overuse of antibiotics in aquaculture is largely considered to be an environmental pollution, because it supports the transfer of antibiotic resistance genes within the aquatic environment. One environmentally friendly alternative to antibiotics is the use of quorum sensing inhibitors (QSIs). Quorum sensing (QS) is a regulatory mechanism in bacteria which control virulence factors through the secretion of autoinducers (AIs), such as acyl-homoserine lactone (AHL) in gram-negative bacteria. Vibrio harveyi QS is controlled through three parallel pathways: HAI-1, AI-2, and CAI-1. Bioassay-guided purification of F. cf reticulata extract was conducted on two bacterial species, i.e., Tenacibaculum maritimum and V. harveyi for antibiotic and QS inhibition bioactivities. Toxicity bioassay of fractions was also evaluated on the freshwater fish Poecilia reticulata and the marine fish Acanthurus triostegus. Cyclohexanic and dichloromethane fractions of F. cf reticulata exhibited QS inhibition on V. harveyi and antibiotic bioactivities on V. harveyi and T. maritimum, respectively. Palauolide (1) and fascaplysin (2) were purified as major molecules from the cyclohexanic and dichloromethane fractions, respectively. Palauolide inhibited QS of V. harveyi through HAI-1 QS pathway at 50 ㎍ ml^-1 (26 μM), while fascaplysin affected the bacterial growth of V. harveyi (50 ㎍ ml^-1) and T. maritimum (0.25 ㎍). The toxicity of fascaplysin-enriched fraction (FEF) was evaluated and exhibited a toxic effect against fish at 50 ㎍ ml^-1. This study demonstrated for the first time the QSI potential of palauolide (1). Future research may assess the toxicity of both the cyclohexanic fraction of the sponge and palauolide (1) on fish, to confirm their potential as alternative to antibiotics in fish farming.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.04a
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• pp.1-6
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• 2003

In injection molding of an optical disk, a toric lens, etc., their performance depends on the transcription preciseness of fine surface structure of a mold. However, transcription behavior has not been made clear yet, because transcription is made in very short time and the structure is very small. In this paper, transcription properties have been examined, by using V-grooves of various sizes. machined on mold surfaces, and the following results are obtained. (1) Transcription properties have been made clear experimentally and it was found that the mold temperature $T_D$ makes great influence on the transcription property and that compression applying time $t_c$ should be taken more than 2.0s for fine transcription. (2) A mechanical model of transcription process, in consideration with strain recovery due to viscoelastic property of polymer. is proposed. (3) Simulation results agree with experimental ones fairly well. It means that the transcription model is useful for estimation of transcription property in advance of an actual. injection molding.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.1
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• pp.45-54
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• 2004

Major symptoms of allergic rhinitis are nasal obstructions, sneezing and watery rhinorrhea. Gamigyeji-tang has been used to treat for watery rhinorrhea, which is one of the symptoms of allergic rhinitis. This experimental study was done to rescarch effects of Gamigyeji-tang. We have studied effect of mice on OVA-induced Production of IL-4, IL-5, IFN-${\gamma}$ by Murine Splenocytes, and effect of OVA-induced total IgE and OVA-Specific IgE. The results were as follows ; 1. In IL-4 study, Gamigyeji-tang treated group was proved significant inhibitory effect(p〈0.005) 2. In IL-5 study, Gamigyeji-tang treated group was proved significant inhibitory effect.(p〈0.05) 3. In IFN-${\gamma}$ study, Gamigyeji-tang treated group was proved significant inhibitory effect(p〈0.000001) 4. In Total IgE, Gamigyeji-tang treated group didn't showed significant inhibitory effect. 5. In OVA-specific IgE, Gamigyeji-tang treated group didn't showed significant inhibitory effect. According to this result, Gamigyejj-tang was concluded to be effective on anti-allergic action. More studies are required to investigate the mechanism of inhibition by herbal medicine in allergic rhinitis model.

• Biomolecules & Therapeutics
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• v.9 no.2
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• pp.88-95
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• 2001

(+)-Methamphetamine (METH) is a psychostimulant, which has been the most popular abused drug in Korea. The rewarding mechanism in METH abuse has been reported to be mediated by dopaminergic system. Recently, it has been reported that dopamine releaser (phentermine) plays a dominant role in the discriminative stimulus effects of METH, whereas 5-HT releaser (fenfluramine) can strongly modify METH self-administration. The present study is designed to assess the behavioral changes and the changes of the serotonin receptors in the brains of rats administered repeated of self-administered METH. The repeated administration of 1.0 mg/kg/day METH for 12 days increased locomotor activities, and there was no difference between i.v. and i.p. treatment. Rats had actively acquired METH self-administration for 3 weeks at 0.1 or 0.2 mg/kg/injection. Whereas, it was taken few days to acquire sucrose pellet self-administration. The binding of [$^3$H]-8-hydroxy-DPAT (5-H $T_{1A}$ receptors) and [$^3$H]-5-carboxytryptamine (5-H $T_{1B}$ receptors) to brain sections was examined. Both passive administration and self-administration of METH did not change significantly the serotonin receptors levels in hippocampus, striatum and nucleus accumbens. These results suggest that serotonin receptors may not change in the acquisition period of METH self-administration, and we are trying to investigate the serotonin receptors levels of brain in rats maintained of METH self-administration.n.n.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.6
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• pp.317-323
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• 2003

Interneuron diversity is one of the key factors to hinder understanding the mechanism of cortical neural network functions even with their important roles. We characterized inhibitory interneurons in layer II/III of the rat primary visual cortex, using patch-clamp recording and confocal reconstruction, and classified inhibitory interneurons into fast spiking (FS), late spiking (LS), burst spiking (BS), and regular spiking non-pyramidal (RSNP) neurons according to their electrophysiological characteristics. Global parameters to identify inhibitory interneurons were resting membrane potential (＞-70 mV) and action potential (AP) width (＜0.9 msec at half amplitude). FS could be differentiated from LS, based on smaller amplitude of the AP (＜∼50 mV) and shorter peak-to-trough time (P-T time) of the afterhyperpolarization (＜4 msec). In addition to the shorter AP width, RSNP had the higher input resistance (＞200 $M{Omega}$) and the shorter P-T time (＜20 msec) than those of regular spiking pyramidal neurons. Confocal reconstruction of recorded cells revealed characteristic morphology of each subtype of inhibitory interneurons. Thus, our results provide at least four subtypes of inhibitory interneurons in layer II/III of the rat primary visual cortex and a classification scheme of inhibitory interneurons.

• Korean Journal of Materials Research
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• v.11 no.8
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• pp.679-684
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• 2001

The surface of natural graphite has not only good electrical conductivities and lubrication properties but also has strong hydrophobicity. There are no functional groups and chemical properties on it. It is difficult to join with any other ions and to disperse in aqueous system. In order to increase dispersion ability throughout modification of surface property, it is necessary to let graphite have some function on its surface by the adsorption of surfactant molecules. In this study, using zeta potential adsorbed surfactant molecules(ABDM) on graphite surface and its surface Properties turn hydrophobic into hydrophilic. The dispersing mechanism of graphite particles in aqueous system has been explained using the DLVO theory, It is concluded that the high dispersable graphite suspension of which dispersing stability$(T_{1/2})$ is 44.5 hours at pH 10 and 22.5mV zeta potential can be produced.

• Journal of the Microelectronics and Packaging Society
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• v.12 no.1 s.34
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• pp.53-58
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• 2005

We researched damage formation and failure mechanism under DC(direct current) and AC(alternative current) in order to estimate reliability of Cu interconnects in ULSI. Higher current density and temperature induces more short TTF(time to failure) during interconnects carry DC. Measurement reveals that Cu electromigration has activation energy of 0.96eV and current density exponent value of 4. Thermal fatigue is occurred under DC, and higher frequency and ${\Delta}$T value gives more severe damage during interconnects carry AC Through failure morphology analysis with respect to texture, we observed that damages had grown widely and facetted grains had appeared in (100)grain but damages in (111) had grown thickness direction of line and had induced a failure rapidly.