• Journal of the Korean Society for Heat Treatment
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• v.21 no.1
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• pp.3-9
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• 2008

Al-Co-N thin films, Al-Co-N/Al-N and Al-Co-N/Al-Co multilayers containing various amounts of Co content were deposited by using a two-facing targets type dc sputtering (TFTS) system. The films were also annealed successively and isothermally at different annealing temperatures. Irrespective of Co content and preparation methods, all the as-deposited films were observed non-magnetized. It was found that annealing conditions can control the magnetic and electrical properties as well as the microstructure of the films.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.133-134
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• 2004

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.253-261
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• 2005

Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.4
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• pp.7-12
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• 2014

IETF (Internet Engineering Task Force) CoAP (Constrained Application Protocol) protocol is supported communication between sensor or actuator nodes by in a constrained environment, such as small amount of memory, and low power. CoAP and HTTP protocol can convert easily, and can use to monitor or controll the infrastructure utility through low-power sensor and actuator networks in IoT (Internet of Thing) and M2M (Machine-to-Machine) environment. IETF CoRE(Constrained RESTful environments) Working Group proposed CoAP protocol in 2010, and began to standardize it. Recently, CoAP protocol is published RFC (Request for Comments) 7252. In this paper, we design and implement of CoAP protocol for testing the interoperability in heterogeneous operating environments. For this experiment, we developed the CoAP client program based on Windows environment and CoAP server program in Linux environment to test the interoperability.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.795-798
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• 2004

After showing 32 inch two-dimensionally integrated fluorescent lamp (TIFL) and its module at SID '04, 40 inch TIFL and its module of prototype have been developed at the first time. It is the biggest size in the world as well as has a backlight unit without BEF optical film. The luminance of TIFL is 14000 nit at 190 watt power consumption and its luminous efficacy is 51 lumen/watt. The use of TIFL simplifies backlight assembly process and removes high price optical sheets. As a result, LCD TV, used by TIFL, is rapidly going to expand its market share in the large size TV area.

• Fire Science and Engineering
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• v.19 no.2 s.58
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• pp.37-44
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• 2005

We have conducted a numerical simulation under three-dimensional unsteady conditions in order to analyze the characteristics of flow and the distribution of $CO_2$ agent concentration according to the number of $CO_2$ agent nozzle. The engine room of a ship was selected as a protection space, and flow fields and $CO_2$ concentration fields were measured. In case of increasing the number of $CO_2$ nozzle from 2 nozzles to 4 nozzles, the distribution of CO2 concentration showed low, and in case of increasing the number of $CO_2$ nozzle to above 6 nozzles, the recirculating flow affected to all region was generated. In case of increasing the number of $CO_2$ agent nozzle to above 4 nozzles, the iso-concentration line below 0.36 expanded or contracted slightly. Therefor, the proper number and the arrangement of $CO_2$ agent nozzle are considered when $CO_2$ fire fighting system is designed.

• Journal of Bio-Environment Control
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• v.11 no.2
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• pp.51-55
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• 2002

Green peppers (Capsicum annuum L. cv, Soonjung) were grown under different combinations of $CO_2$ concentration and temperature levels and examined on the effect of elevated $CO_2$ and temeprature on plant growth, carbon and nitrogen concentrations. Plant height was stimulated by elevated $CO_2$ levels at 20.3 and 22.6$^{\circ}C$. Leaf area and fresh weight were remarkedly increased by high $CO_2$ concentration at 22.6$^{\circ}C$. Dry weights of leaf, stem, root, and whole plant were increased as temperature increased at 611 ppm $CO_2$, but those values decreased at 22.6$^{\circ}C$ in 397 ppm $CO_2$ concentration. Elevated $CO_2$ increased plant growth by 1.5 times at 20.5$^{\circ}C$ and 22.6$^{\circ}C$. C/N ratio increased with increasing temperature under elevated $CO_2$ levels.

• Resources Recycling
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• v.9 no.4
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• pp.37-43
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• 2000

Leaching of $LiCoO_2$ as a cathodic active materials for recovering Li and Co from spent lithium ion battery was investigated in terms of reaction variables. At the optimum condition determined in the previous work, Li and Co in a $H_2SO_4$ and $HNO_3$ solution were dissolved 70~80% and 40%, respectively. Li and Co were leached over 95% with the addition of a reductant such as $Na_2S_2O_3$ or $H_2O_2$. This behavior is probably due to the reduction of $Co^{3+}$ to $Co^{2+}$. Leaching of $LiCoCo_2$ powder obtained by calcination of an electrode materials from spent batteries was also carried out. Leaching efficiency of Li and Co were over 99% at the optimum condition with $H_2O_2$ addition of 1.7 vol.%. It seems to be due to the activation of $LiCoO_2$ by repeated charging and discharging or an imperfect crystal structure by deintercalation of Li.

• Polymer(Korea)
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• v.35 no.6
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• pp.586-592
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• 2011

In this study, we synthesized vinylbenzyl chloride-co-styrene-co hydroxyethyl acrylate (VBC-co-St-co-HEA) copolymer that can be applied to redox the flow battery process. The anion exchange membrane was prepared by the amination and crosslinking of VBC-co-St-co-HEA copolymer. The chemical structure and thermal properties of VBC-co-St-co-HEA copolymer and aminated VBC-co-St-co-HEA(AVSH) membrane were characterized by FTIR, $^1H$ NMR, TGA, and GPC analysis. The membrane properties such as ion exchange capacity(IEC), electrical resistance, ion conductivity and efficiency of all-vanadium redox flow battery were measured. The IEC value, electrical resistance, and ion conductivity were 1.17 meq/g, $1.9{\Omega}{\cdot}cm^2$, 0.009 S/cm, respectively. The charge-discharge efficiency, voltage efficiency and energy efficiency from all-vanadium redox flow battery test were 99.5, 72.6 and 72.1%, respectively.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2019.05a
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• pp.341-342
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• 2019