• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.6
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• pp.499-502
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• 2008

In this work, Ga-doped ZnO (GZO) thin films for gas sensor application were deposited on low temperature co-fired ceramics (LTCC) substrates, by RF magnetron sputtering method. The LTCC substrate is one of promising materials for this application since it has many advantages (e.g., low cost production, high manufacturing yields and easy realizing 3D structure etc.). The LTCC substrates with thickness of $400\;{\mu}m$ were fabricated by laminating 12 green tapes which consist of alumina and glass particle in an organic binder. The structural properties of the fabricated GZO thin film with thickness of 50 nm is analyzed by X-ray diffraction method (XRD) and field emission scanning electron microscope (FESEM). The film shows good adhesion to the substrate. The GZO gas sensors are tested by gas measurement system and show fast response and recovery characteristics to $NO_x$ gas that is 27.2 and 27.9 sec, recpectively.

• Journal of Mechanical Science and Technology
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• v.15 no.6
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• pp.804-812
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• 2001

A triboelectrostatic separation system for removing unburned carbon from coal fly ash is designed and evaluated. Fly ash from a coal-fired power plant is used as an accepted additive in concrete where it adds strength, sulfate resistance and reduced cost, provided acceptable levels of unburned carbon are maintained. Unfortunately, unburned carbon in coal fly ash absorbs some of other additives and reduces the concrete strength. This paper describes to investigate dry triboelectrostatic process to separate unburned carbon from coal fly ash and utilize it into economically valuable products. The laboratory-scale triboelectrostatic separation system consists of a particle feeding system, a tribocharger, a separation chamber, and collection systems. Particles of unburned carbon and fly ash can be imparted positive and negative surface charges, respectively, with a copper tribocharger due to differences in the work function values of the particles and the tribocharger, and can be separated by passing them through an external electric field. Results showed that fly ash recovery was strongly dependent on the electric field strength and the particle size. 70wt% of fly ash containing 6.5wt% of carbon contents could be recovered at carbon contents below 3%. The triboelectrostatic separation system showed a potential to be an effective method for removing unburned carbon from coal fly ash.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.1
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• pp.160-167
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• 2002

Stretch fabrics are wide-spread for high performance clothing use with requirements of fitness and adaptability to human's movement. A newly developed 100% PET high stretch fabric has excellent properties with respect to stretch, softness, bulkiness, and apparent volume compared to PET filament fabrics. The 100% PET high stretch fabric shows advantages of a dimensional stability, dye and agent adaptability in dying and finishing process, a property of stretch recovery after washing and lower production cost than that of spandex fabric. KES-FB was used to measure mechanical properties to various directions of the fabric. This study centered on whether the 100% PET high stretch fabric is suitable to quality and shape retention of fabric by testing several properties including tensile, compression, shear, bending and surface characteristic to various measuring directions. Tensile linearity showed maximum value at $0^{\circ}$ in plain and $90^{\circ}$ in twill. Shear Stiffness of plain and twill showed maximum value equally at $45^{\circ}\;and\;135^{\circ}$. Bending rigidity showed maximum value at $0^{\circ}$ in plain and $45^{\circ}$ twill. Mean deviation of MIU showed maximum value at $0^{\circ}\;and\;90^{\circ}$ in plain and $135^{\circ}$ in twill.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.26 no.3
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• pp.9-22
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• 2018

Korea meteorological administration(KMA) has started to levy air meteorological service charge on both national and foreign carriers since 2005. The charge has grown on 2010 and 2014 twice. However, KMA has still kept asking airlines to agree with another increase in the charge due to the low cost of goods recovery ratio of 7%. The air meteorological charge has changed from 2,210 KRW at the beginning to 11,400 KRW as of June 2018. According to ARIMA intervention time series analysis, it was proven national carriers would make a payment of 831 million KRW 2018 and 1,024 million KRW 2019, showing 186.2% and 123.2% increase compared to last year respectively. The total amount of charge for both national LCC and foreign airlines was aggregated up to 1,952 million KRW 2019, 227% bigger than the charge paid at 2017. Considering the 50% increase of consumer price index last decade, the increased charge would impair the global competitiveness of national carriers. It could be suggested that current air meteorological charge scheme be improved to apply overseas trend and for national carriers to have a competitive advantage in global aviation market.

• Journal of Advanced Navigation Technology
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• v.13 no.5
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• pp.699-704
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• 2009

The requirements of disaster prevention have been constantly increasing on highly disaster frequency by Global warming and environmental destruction. The damage occur more highly, especially when it's on the localized change of weather. It requires that we have methods of disaster prevention locally. In this paper, we design and implement a breakwater disaster prevention system integrated wireless sensor technique for the shore breakwater of East Sea that is raised anxiety about an accident occurrence due to stormy weather. The provided disaster prevention system perceive the seriousness of the situation that is chance of that happening by the information of realtime remote situation and a prediction system so that it could be of some help to reduce the damage of disaster and the cost of recovery.

• International Commerce and Information Review
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• v.12 no.3
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• pp.79-98
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• 2010

The National Conference of Commissioners on Uniform State Laws promulgated the Uniform Computer Information Transactions Act (UCITA) in 1999. In 2000 and 2002, this Act was also Amended. UCITA provides a comprehensive set of rules for licensing computer information, whether computer software or other clearly identified forms of computer information. Computerized databases and computerized music are other examples of computer information that would be subject to UCITA. It would also govern access contracts to sites containing computer information, whether on or off the Internet. UCITA would not govern contracts, even though they may be licensing contracts, for the traditional distribution of movies, books, periodicals, newspapers, or the like. Part 8 of UCITA provides a remedy structure somewhat modeled on that of Article 2 but adapted in significant respects to the different context of a computer information transaction. For example, 808 of UCITA recognizes the focus in a license context for a licensor's remedy should properly be on recovery for benefit conferred or for lost profit, rather than on damage measurement by a substitute transaction, where the license is non-exclusive so additional transactions are permitted and there is very little cost in reproduction of the information and its redistribution. Section 816 of UCITA also contains very important limitations on the generally recognized common law right of self-help as applicable in the electronic context.

• International Journal of Fluid Machinery and Systems
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• v.9 no.3
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• pp.256-264
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• 2016

To meet the demand of higher handling capacity, a mixed-flow submersible deep well pump was designed and tested. The main hydraulic components are made of plastics, which is free of erosion, light-weight, and environment-friendly. To simplify plastic molding process, and to improve productivity, an axial-radial guide vane was proposed. To clarify its effect on the performance, a radial guide vane and a space guide vane are developed as well. By comparison, the efficiency of the pump equipped with the axial-radial guide vane is higher than the radial guide vane and is lower than the space guide vane, and its high efficiency range is wide. The static pressure recovery of the axial guide vane is a bit lower than the space guide vane, but it is much larger than the radial guide vane. Taking the cost and molding complexity into consideration, the axial-radial guide vane is much economic, promoting its popularity for the moderate and high specific speed submersible deep well pumps.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.1
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• pp.45-53
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• 2015

The objective of this study is to develop a gas pro-treatment system for DME synthesis, wherein this system separates $CO_2$ from Flaring gas as Membrane, in order to save raw material ($CH_4$) cost of DME. In this study, hollow fiber membrane is developed, which is able to separate high-pressure gas, supported by polysulfone and coated with amorphous fluorinated polymer. Throughout the evaluation of the membrane's separation characteristics, the membrane is applied to this system. The membrane is designed by 2 stages for over 90% removal rate of $CO_2$ and over 90% recovery rate of $CH_4$. The bench scale of pro-treatment system is developed as $25Nm^3/hr$.

• Current Industrial and Technological Trends in Aerospace
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• v.8 no.1
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• pp.12-22
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• 2010

The great recession which caused by financial crisis made steep rise of oil price and the serious problems of the aircraft industry. High oil price increases operating cost and the recession decreases air traffic. After a period of high book order and delivery from global economic recovery, the aircraft order fell down suddenly. Also the Aircraft price and lease rate deceased and the MRO market is reduced, too. But, the air cargo and passenger increase again since late of 2009. So, it is difficult to predict the market movement, most of the forecasters agreed that the air traffic and aircraft demand will grow gradually in long term with the growth of emerging markets like China, India and Africa. And more efficient, safe and clean aircraft is needed and will need in the market.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.8
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• pp.318-330
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• 2003

The advantages of "VPN over Internet" are cost-effectiveness and flexibility However, the disadvantages are the lack of sufficient QoS mechanism and transmission capacity for high bandwidth service. Given this increasing demand for high bandwidth Internet and QoS assurances in "PN over Internet", IP/GMPLS based control plane combined with a high bandwidth capacity of DWDM optical network is seen as a very favorable approach for the realization of future "OVPN over IP/GMPLS over DWDM" Within OVPN for providing QoS guaranteed multimedia service over the NGOI(Next Generation Optical Internet) based on the "IP/GMPLS over DWDM" concept, differentiated QoS framework is one of the key issues to implement OVPN over DWDM-based NGOI. Keeping in mind that IETF(Internet Engineering Task Force) and ITU-T(International Telecommunication Union) are standardizing IP/GMPLS over DWDM protocol framework as a solution for the NGOI, in this paper, we suggest Optical-LSP establishment and QoS maintenance scheme based on DOQS(Differentiated Optical QoS Service) classes, which are the key issue of DOQS protocol framework for assuring end-to-end QoS in "OVPN over IP/GMPLS over DWDM".