• Biomolecules & Therapeutics
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• v.19 no.1
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• pp.109-117
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• 2011

In this work, we have investigated the effect of polyoxyethylene alkyl ester nonionic surfactants on percutaneous permeation enhancement of a model drug, ketoprofen. We also investigated the mechanism involved in the enhancement using impedance and solubility measurement. Three groups of nonionic surfactants with different ethylene oxide content were studied. The permeation results showed that all surfactants enhanced the percutaneous absorption, irrespective of the molecular weight. The permeation results from PEG-45 monostearate (PEGMS45) were rather unexpected. Impedance and solubility results indicate that the mechanism involved in the enhancement of permeation by PEG-10 monooleate (PEGMO10) and PEGMS45 is rather different. The results from PEGMS45 suggest that it could be a potential candidate as a skin penetration enhancer with high molecular weight, which may poses less skin irritation and systemic side effect than the smaller surfactant molecules. Overall, this work provided some useful information on percutaneous transport enhancement and the mechanistic insights involved in skin permeation for these nonionic surfactants.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.21 no.2
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• pp.85-91
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• 2013

The NGAP and TRAINAIR PLUS programme goal is to improve the safety and efficiency of air transport through the establishment, maintenance and monitoring of high standards of training and competency of aviation personnel on a world-wide basis and in a cost-effective manner. According to the trend, the approval of training organization must be change. In this study, personnel training system and certification mechanism were studied.

• Korean System Dynamics Review
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• v.11 no.1
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• pp.5-26
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• 2010

To revitalize the trucking market, many studies are being done but it still has a lot of problems such as imbalance between supply and demand, poor profit structure of truck owners, ect. Therefore, it aims to study what kinds of prerequisite are needed to solve these problems through analyzing system structure and mechanism of the market. To achieve it, System Dynamics methodology, appropriate to make a simulation model and analyze dynamics of the system, is utilized. To obtain an empirical research point of view, time series data related on trucking market-provided by The Korea Transport Institute-are used. In addition, interview with a local representative logistics company and a ICD(Inland Container Depot) operation company is performed to find out technical and functional supporting factors to solve the existing problems in the market.

• Journal of Surface Science and Engineering
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• v.36 no.2
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• pp.141-147
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• 2003

Silicon carbide thin film was deposited in APCVD and LPCVD system with 1,3-DSB precursor 1,3-DSB is the single precursor to deposit SiC on Si at low temperature. SiC film was deposited at $850^{\circ}C$ lower than ordinary temperature ($1000~1200^{\circ}C$) in CVD process. SiC thin film glowed to high oriented (111) plane in APCVD system. In LPCVD system, SiC film groved to preferred (220) plane at same temperature. This discrepancy between preferred planes can be described by the difference of deposition mechanism. Amorphous phase and crystal defect were observed in APCVD system with the main growth mechanism of mass transport limited region. But in LPCVD system, we got the SIC film of uniform, faceted structure and high quality.

• Journal of Integrative Natural Science
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• v.5 no.2
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• pp.72-78
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• 2012

Multidrug resistance is a major obstacle in cancer chemotherapy. Cancer cells efflux chemotherapeutic drug out of cell by means of transporter and reduce the active concentration of it inside cell. Such transporters are member of the ATP binding cassettes (ABC) protein. It includes P-gp, multiple resistant protein (MRP), and breast cancer resistant protein (BCRP). These proteins are widely distributed in the human cells such as kidney, lung, endothelial cells of blood brain barrier etc. However, there are number of drugs developed for it, but most of them are getting transported by it. So, still there is necessity of a good modulator, which could effectively combat the transport of chemotherapeutic agents. Natural products origin modulators were found to be effective against transporter such as flavonoids, which belongs to third generation modulators. They have advantage over synthetic inhibitor in the sense that they have simple structure and abundant in nature. This review focuses on the P-gp structure its architecture, efflux mechanism, herbal inhibitors and their mechanism of action.

• ETRI Journal
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• v.26 no.2
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• pp.112-121
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• 2004

Digital Multimedia Broadcasting (DMB) is an upcoming standard in Korea used to provide mobile multimedia broadcasting service based on the Eureka-147 Digital Audio Broadcasting (DAB) system. The current dominant multimedia coding standard, MPEG-4, is foreseen to play an important role in forthcoming DMB services. However, the current approaches for transporting MPEG-4 content over DMB networks are not optimized. To address this issue we propose a novel MPEG-4 stream multiplexer, called M4SMux, which provides better stream multiplexing and delivery over DMB networks. M4SMux features an MPEG-4 elementary-stream interleaving mechanism that reduces the multiplexing overhead and a multiplex configuration mechanism that utilizes M4SLinkTable for easy content access. In addition, we propose an error correction method which enhances transport efficiency.

• 한국전산유체공학회:학술대회논문집
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• 2002.05a
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• pp.115-120
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• 2002

A two-dimensional direct numerical simulations was peformed to investigate the flame structure of $CH_4/N_2$-Air counterflow nonpremixed flame interacting with a single vortex. The detailed transport properties and a modified 16-step augmented reduced mechanism based on Miller and Bowman's detailed reaction mechanism were adopted in this calculation. To quantify the strain on flame induced by a vortex, a scalar dissipation rate (SDR) is introduced. Results show that the fuel- and air-side vortex cause an unsteady extinction. In this case, the flame interacting with a vortex is extinguished in much larger SDR than steady flame. It was also found that air- side vortex extinguishes a flame more rapidly than fuel -side vortex.

• Korean Journal of Bronchoesophagology
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• v.3 no.2
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• pp.313-317
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• 1997

Airway mucus provides the protective functions such as lubrication, barrier, disposal of trapped materials, and humidification. In the normal state, the mucus do not interfere with Bas transport and the other vital functions of lung. In diseases such as asthma, bronchitis, and cystic fibrosis, the mucus hypersecretion was physiologically developed in the response of multiple neurohumoral mechanism system. And regardless of the mechanism, many clinical sequelae result from mucus hypersecretion: atelectasis, infection, increased airway resistance, increased work of breathing, increased cough with its resultant complication. And the condensation of mucus tv mucus hypersecretion can make the mucus plug by which bronchial obstruction is developed. We have experienced a 7 Pear-old male patient with recurrent pneumonic symtom, which the bronchial obstruction was developed by the impacted mucus plug on the bronchoscopic finding. We report this case with the review of literature.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.291-294
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• 2006

Studies of the effectiveness of anthraquinone (AQ) in kraft-AQ pulping in terms of its mechanism of mass transfer have been conducted. Experiments performed have demonstrated an 'apparent solubility' of AQ in caustic solutions of wood lignin. The adsorption behavior of AQ species was also analyzed. Anthraquinone-2-sulfonic acid (AQ-S), a water-soluble derivative of AQ, showed selective adsorption on wood. A mechanism for the transport of AQ into wood chips during kraft pulping are proposed, and some explanations for previously unexplained observations are addressed.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.6
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• pp.163-172
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• 2003

Proposed in this paper is an authentication mechanism for multimedia streaming data in the Intemet multicast environment. The multicast authentication mechanism is coupled with the packet-level forward error correction code which has been recently applied for a reliable multicast transport transmission. Associated with this, Reed-Solomon erasure code is chosen for tolerating packet loss so that each of the received packets can be authenticated independently of the lost packets.