• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.492-496
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• 2001

Due to their better photosensitivity in X-ray, the amorphous selenium based photoreceptor is widely used on the X-ray conversion materials. It was possible to control the charge carrier transport of amorphous selenium by suitably alloying a-Se with other elements(e,g. As, Cl). In this paper, We investigated dopants(As, Cl) composition rate to improve dark resistivity and transport properties of charge carrier in amorphous selenium using by direct X-ray conversion material. Alloying a-Se with As inhibits the recrystallization of a-Se but introduces undesirable deep hole traps. then doping with Cl(in the ppm range) compensates for the deep hole traps. We investigated their composition rate in various doping conditions and then obtained optimum dopant composition rate. The result was Se-As 0.3%-Cl 30 ppm and X-ray Sensitivity was 0.57 pc/pixel$.$mR at 137 $\mu\textrm{m}$ x 137 $\mu\textrm{m}$ Pixel area.

• Journal of Mechanical Science and Technology
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• v.19 no.6
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• pp.1378-1389
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• 2005

This work provides the fundamental knowledge of energy transport characteristics during very short-pulse laser heating of semiconductors from a microscopic viewpoint. Based on the self-consistent hydrodynamic equations, in-situ interactions between carriers, optical phonons, and acoustic phonons are simulated to figure out energy transport mechanism during ultrafast pulse laser heating of a silicon substrate through the detailed information on the time and spatial evolutions of each temperature for carriers, longitudinal optical (LO) phonons, acoustic phonons. It is found that nonequilibrium between LO phonons and acoustic phonons should be considered for ultrafast pulse laser heating problem, two-peak structures become apparently present for the subpicosecond pulses because of the Auger heating. A substantial increase in carrier temperature is observed for lasers with a few picosecond pulse duration, whereas the temperature rise of acoustic and phonon temperatures is relatively small with decreasing laser pulse widths. A slight lagging behavior is observed due to the differences in relaxation times and heat capacities between two different phonons. Moreover, the laser fluence has a significant effect on the decaying rate of the Auger recombination.

• International Commerce and Information Review
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• v.12 no.2
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• pp.385-405
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• 2010

The purpose of this study is to investigate liability risk of air cargo carrier and suggests ideas for solving problems which could be happen to air transporters on the future. because of Air transport remains one of the world's fastest growing and most important industries. And important treaties and contracts specifying transporters' responsibility regarding big scale aircraft accidents are such as Warsaw Convention in 1929, Hague Protocol in 1955, Montreal Convention in 1999. The Montreal Convention, formally the Convention for the Unification of Certain Rules for International Carriage, is a treaty adopted by Diplomatic meeting of ICAO member states in 1999. It amended important provisions of the Warsaw Convention's concerning compensation for the victims of air disasters. In conclusion, suggests to the method of air cargo security and cargo legal liability insurance which is for air cargo carrier's risk management.

• Journal of the Korean Institute of Navigation
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• v.21 no.1
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• pp.89-102
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• 1997

Since 1979, the People's Republic of China has been opeining their marke tprogressively toward all over the world for developing its own domestic economy and international trade. China also has paid a great attention to the international maritime transport due to the fact that its volume of international trade has increased continuoulsy. Under such circumstance, the Chinese Maritime Code was issued in 1992 in which the regulation with regard to carrier's liability occupied an important position. The author, therefore, selected this issue for demonstration of the legal proinciples about carrier's liability which is provided in the Chinese Maritime Code. The study on the issue is under guidance of related international conventions. On the basis of the above, the differences between the Code and relevant conventions have been pointed out in order to make the people in the field of shipping understood for legal system with regard to carrier's liability in China which is a great potential partner of Korea in shipping and trade.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.74
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• pp.55-79
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• 2017

The Rotterdam Rules introduces new issues that have been ignored by previous international transport conventions. Among them, provisions on delivery of goods have been a much debated topic as it deviate from well established principles. Rotterdam Rules provides several alternatives in order to resolve uncertainty regarding delivery practice. The carrier have to make a resonable effort to deliver the goods following the required procedure which is different from transport document issued. Where the goods are not deliverable, the carrier could discharge from its obligations to deliver the goods when he deliver the goods by delivery instruction of shipper. In addition, he can take actions reasonably required according to circumstances if it is impossible to deliver the goods. These alternatives are not ideal, but they seem to be partly helping to solve practical problems arising in the process of delivery. However the delivery regime under the Rotterdam Rules could cause confusion in the traditional delivery principle. On the other hand, it puts a new burden on the parties concerned. In conclusion, the parties concerned should consider practical implications in issuing and transferring transport document as well as requesting and instructing delivery of goods.

• YAKHAK HOEJI
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• v.38 no.2
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• pp.114-122
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• 1994

A study on the absorption mechanism of cefixime(CF), an oral ${\alpha}-amino$ group deficient cephalosporin antibiotic, has been undertaken through the rat jejunum and nasal cavity using an in situ simultaneous perfusion technique developed in our laboratory. CF was well absorbed in the jejunum and nasal cavity of rats at pH 5.0, but not at pH 7.0. CF absorption was studied over four orders of magnitude in concentration to determine saturability. Disappearance of CF in the perfusate followed first-order kinetics at all tested concentrations. The apparent first-order absorption rate constant was found to be dependent on the concentration over the range of $0.1\;mM{\sim}3\;mM$ in the jejunum and nasal cavity of rats. Inhibitors were added to determine the competitive inhibition of CF absorption. The presence of L-tyrosine, L-phenylalanine, alanine-alanine, glycine-glycine and cefadroxil produced the significant inhibition of CF absorption in the nasal cavity and jejunum. However, there was no evidence of the inhibition in the presence of cefazolin. In addition, The CF absorption in the nasal cavity and jejunum was inhibited significantly by ouabain and 2,4-dinitrophenol(DNP). This study suggested that CF is absorbed across the rat nasal cavity and jejunum by carrier-mediated transport mechanism and energy consuming system.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.97-97
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• 2013

We present a comprehensive study on the integration of h-BN with silicon MOSFET. Temperature dependent mobility modeling is used to discern the effects of top-gate dielectric on carrier transport and identify limiting factors of the system. The result indicates that coulomb scattering and surface roughness scattering are the dominant scattering mechanisms for silicon MOSFETs at relatively low temperature. Interposing a layer of h-BN between $SiO_2$ and Si effectively weakens coulomb scattering by separating carriers in the silicon inversion layer from the charged centers as 2-dimensional h-BN is relatively inert and is expected to be free of dangling bonds or surface charge traps owing to the strong, in-plane, ionic bonding of the planar hexagonal lattice structure, thus leading to a significant improvement in mobility relative to undecorated system. Furthermore, the atomically planar surface of h-BN also suppresses surface roughness scattering in this Si MOSFET system, resulting in a monotonously increasing mobility curve along with gate voltage, which is different from the traditional one with a extremum in a certain voltage. Alternatively, high-k dielectrics can lead to enhanced transport properties through dielectric screening. Modeling indicates that we can achieve even higher mobility by using h-BN decorated $HfO_2$ as gate dielectric in silicon MOSFETs instead of h-BN decorated $SiO_2$.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.63-63
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• 2010

Ability to transport extracted carriers from NQDs is essential for the development of most NQD based applications. Strategies to facilitate carrier transport while preserving NQDs' optical characteristics include: 1) Fabricating neat films of NQDs with modified surfaces either by adapting series of ligands with certain limitations or by applying physical processes such as heat annealing 2) Coupling of NQDs to one-dimensional nanostructures such as single walled carbon nanotubes (SWNTs) or various types of nanowires. NQD-nanowire hybrid nanostructures are expected to facilitate selective wavelength absorption, charge transfer to 1-D nanostructures, and efficient carrier transport. Even with the vast interests in using NQD-SWNT hybrid materials in optoelectric applications, still, no reports so far have clearly elucidated the optoelectric behavior when they were assembled on the FET mainly because the complexity involving in both components in their preparation and characterization. We have monitored the optical properties of both components (NQDs, SWNTs) from the synthesis, to the assembly, and to the device. More importantly, by using pyridine molecules as a linker to non-covalently attach NQDs to SWNTs, we were able to assemble NQDs on SWNTs with precise density control without harming their electronic structures. Furthermore, by measuring electrical signals from the fabricated aligned SWNTs-FET using dielectrophoresis (DEP), we were able to elucidate the charge transfer mechanism.

• Bulletin of the Korean Chemical Society
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• v.13 no.4
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• pp.355-357
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• 1992

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.51-61
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• 2008

Most of Korea's 15 local airports, with the exception Jeju, Gimpo and Gimhae airports, have been several billion Won in the red each year. It has been reported that one of the causes of the poor financial performance is inaccurate air traffic demand predictions. Under the situation, the entry of low-cost carrier air service using turbo-prop airplanes into the domestic airlines market gets a wide range of support, which is expected to promote the convenience of consumers and help to activate local airports. In this study, the authors (1) suggest a high-speed transport demand model among existing airlines, Korea Train Express (KTX) and low-cost carrier air service; (2) try to make low-cost air carrier demand predictions for a route between Seoul and Daegu through a stated-preference survey; and (3), examine possible effectiveness of selected policy measures by establishing an estimation model. First, fare has a strong influence for mode choice between high-speed transport modes when considering the entry of low-cost carrier air service between Seoul and Daegu. Even low-cost carrier air service fare is set at 38,000 won, which is considerably low compared with that of KTX, in the regions where the total travel time is the same for both low-cost carrier air service and KTX, the probability of selecting low-cost carrier air service is 0.1, which shows little possibility of modal change between high speed transportation means. It is suggested that the fare of low-cost air service between Seoul and Daegu should be within the range of from of 38,000 to 44,000 Won; if it is higher, the demand is likely to be lower than expected.