• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1268-1277
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• 2023

In this study, to evaluate the possibility of utilizing Chamaecyparis obtusa (Siebold & Zucc.) Endl. (C. obtusa) leaf fractions as anti-inflammatory functional materials, C. obtusa extract extracted with 99% ethanol (CO99EL) was fractionated with hexane (CO99EL-H), chloroform (CO99EL-C), ethyl acetate (CO99EL-E), butanol (CO99EL-B) and distilled water (CO99EL-W). The anti-inflammatory effects of each fraction was performed using lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophages. Cytotoxicity was highest in CO99EL-H and CO99EL-C and lowest in CO99EL-W. Interestingly, LPS-induced iNOS expression and NO production were significantly reduced by CO99EL-H and CO99EL-E, and COX-2 expression was significantly reduced by CO99EL-B and CO99EL-W. In addition, interleukin (IL)-1𝛽, an inflammatory cytokine increased by LPS, was significantly reduced by CO99EL-C, CO99EL-E, CO99EL-B and CO99EL-W, and IL-6 was significantly reduced by CO99EL-B and CO99EL-W. Therefore, the janus kinase (JAK)/signaling transducer and activator of transcription (STAT) signaling pathway activated by LPS was significantly reduced by CO99EL-H and CO99EL-C, and the mitogen-activated protein kinase (MAPK) signaling pathway was slightly reduced by CO99EL-H and CO99EL-C. However, nuclear factor (NF)-𝜅B activity was not reduced by any fractions. Based on the results of this study, it was confirmed that CO99EL fractions have different anti-inflammatory mechanisms depending on the solvent used for fractionation.

• Environmental and Resource Economics Review
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• v.20 no.1
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• pp.1-31
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• 2011

By employing Environmental Input-Output Table 2005, which has 76 intermediate sector and 21 energy sources, this paper analyses the flow of energy demand and $CO_2$ after estimating an induced $CO_2$ emissions from 76 industrial sectors. Index of $CO_2$ intensity($CO_2/GDP$) and other index of $CO_2$ intensity($CO_2/calory$) showed that final demand sector uses more high calory energy source. Intermediate sector used less environmental friendly energy source and emit more $CO_2$ at same calory. Industries those has high induced $CO_2$ emissions are Thermal Power($32.587CO_2-g/Won$), Cement($10.370CO_2-g/Won$), Road Transportation($7.255CO_2-g/Won$), Cokes and Other Coal Products($5.791CO_2-g/Won$), Steam and Hot water supply, Sewage, Sanitary services($4.575CO_2-g/Won$). It is shown that industry such as Iron and Steel which has low $CO_2$ intensity, high backward linkage effect and high forward linkage effect makes high induced $CO_2$ emissions. Environmental load and $CO_2$ emissions in overall economy will decrease when not high $CO_2$ intensity industry but also low $CO_2$ intensity industry makes lower $CO_2$ intensity.

• Fire Science and Engineering
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• v.18 no.4
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• pp.27-34
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• 2004

We have conducted a numerical simulation under three-dimensional unsteady conditions in order to analyze the effect of flow and CO₂ mass transfer according to the distance between the CO₂ nozzle of CO₂ fire fighting system and the rear wall in a protection space. Flow fields and CO₂ concentration fields were measured. The different recirculation flow form and wall jet was developed according to increasing the distance between CO₂ nozzles and rear wall. In all the case, CO₂ mass transfer was generated toward the center of a protection space from each walls, but the CO₂ mass fraction of front and rear areas based on CO₂ nozzles showed higher or lower by increasing the distance between CO₂ nozzle and rear wall.

• Journal of the Korean Chemical Society
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• v.37 no.12
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• pp.1019-1024
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• 1993

The coadsorption of carbon monoxide and oxygen on polycrystalline nickel surface has been studied using XPS at the room temperaure. The adsorption of CO on the nickel surface precovered partially with oxygen is found to take place by the following steps: The CO molecules react with the preadsorbed oxygen atoms to liberate $CO_2$ gas at the initial stage of low CO exposures, and they are coadsorbed gradually with the increasing CO exposures. The extent of coadsorption at the higher CO exposures is found to decrease with the increasing degree of oxygen preadsorption. This finding is explained in terms of the reduced adsorption site for CO as a consequence of oxygen preadsorption. The CO molecules preadsorbed on the nickel surface inhibited the adsorption of $O_2$ molecules. The increase of oxygen exposure led to the dissociation of preadsorbed CO, and the NiO layers were formed concurrently. The dissociation was rendered to arise from an oxygen-to-CO energy transfer.

• Bulletin of the Korean Chemical Society
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• v.28 no.12
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• pp.2442-2444
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• 2007

CO adsorbates on the surface of Pt supported on carbon catalysts (Pt/C) were investigated by CO stripping voltammetry. Three types of CO adsorbed samples were prepared: by methanol dehydrogenation only (COm), by CO gas bubbling only (COg), and by methanol dehydrogenation followed by CO gas bubbling (COm+g). Our coverage data show that CO gas can be adsorbed on Pt/C catalyst already saturated with CO adsorbates by methanol dehydrogenation. The COm+g sample showed the properties of both COm as well as COg samples in terms of the potential although the CO adsorbed by dehydrogenation was completely exchanged with CO in the electrolyte solution. Therefore, the oxidation pathways of CO on Pt/C were observed to depend on the initial adsorption conditions of CO more strongly than on the CO coverage. Our results imply that an initial CO poisoning condition in fuel cell operation is an important factor to determine the difficulty in removing the adsorbed CO and confirm that the properties of the adsorbed CO do not change even with chemical replacement with CO in different conditions. In addition, our results indicate a low CO surface mobility on the Pt in an electrolyte solution.

• The Korean Journal of Physiology
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• v.1 no.2
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• pp.185-191
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• 1967

In order to evaluate the elimination of CO through the lung comparing with the decrease of CO content in the blood, authors had induced acute CO poisoning on 9 dogs. Arterial CO-Hb saturation, CO concentration, %, in expired gas and eliminated CO amount through the lung were measured at 1,5,10,30,60, and 120 minutes after acute CO poisoning in 6 dogs breathing room air and 3 dogs breathing room air and oxygen alternately. Results obtained are summarized as follows. In room air breathing group, arterial CO-Hb saturation averaged 50.8% , and 53.67 ml of CO was blew off through the lung during 120 minutes and in alternately air and oBygen breathing group, the arterial CO-Hb saturation averaged 65.6% and 95.6 ml of CO was blew off through the lung. The amount of CO eliminated in expired gas for 120 minute was much less than the amount of decreased CO in arterial blood which was calculated with the decreased CO-Hb content in the estimated circulating blood volume. Such difference between the amount of eliminated CO in expired gas and the decreased CO in blood might be attributed to the oxidation of CO to $CO_2$ in the tissues. Concentration of CO in expired gas was markedly increased and the rate of decrease in arterial CO-Hb saturation is enhanced by oxygen breathing. In early period of recovery from acute CO poisoning, neither the CO concentration in expired gas, nor, the rate of CO elimination (unlit 2 minutes after CO poisoning) showed close correlation with the blood CO-Hb saturation level. The reason seemed to be due to irregularly depressed or unevenly stimulated respiration which were induced by acute CO poisoning.

• Convergence Security Journal
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• v.17 no.5
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• pp.77-85
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• 2017

In this paper, we propose a key establishment scheme for multicast CoAP security. For multicast CoAP applications, a CoAP Request message from a CoAP client is sent to a group of CoAP servers while each CoAP server responds with a unicast CoAP Response message. In this case, the CoAP Request message should be secured with a group key common to both the CoAP client and servers, while a pairwise key(unicast key) should be employed to secure each CoAP Response message. In the proposed protocol, the CoAP client and the CoAP server establish the group key and the pairwise key using the ECDH in the initial CoAP message exchange process. The proposed protocol, which is highly efficient and scalable, can replace DTLS Handshake and it can support end-to-end security by setting pairwise keys.

• Journal of Distribution Science
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• v.13 no.12
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• pp.105-111
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• 2015

Purpose - Many global companies across industries are paying significant attention to co-creation activities, which enable consumers to participate in firms' value creation process, as a main model of new product development processes. In this study, we aim to examine different types of co-creation activities and their effects on consumer attitudes. We focus on upstream co-creation, downstream co-creation, autonomous co-creation, and sponsored co-creation. Upstream co-creation includes firms' control and management in the initial stage of new product development and prototype testing. Downstream co-creation indicates that consumers participate in firms-initiative activities at a later stage in new product development, such as public relations and marketing communications. Autonomous co-creation includes consumers' commitment activities in the absence of firms' rewards. However, under the sponsored co-creation, consumers can return monetary and social rewards from firms through their co-creation activities. The hypotheses regarding the effect of co-creation on consumer attitudes are as follows. (H1, H2, H3, H4) Upstream, downward, autonomous, and sponsored co-creation has positive effects on consumer attitude. (H5, H6) As intrinsic motivation increases, the positive effect of upstream and autonomous co-creation increases. (H7, H8) As extrinsic motivation increases, the positive effect of downward and sponsored co-creation increases. Research design, data, and methodology - To achieve our research goals, we analyzed responses from 246 samples from Korean consumers and verified the proposed hypotheses using a linear regression model. The samples include Korean consumers who experienced upstream, downstream, autonomous, and sponsored co-creation by firms. Results - First, both upstream co-creation and downstream co-creation with firms and consumers are found to have positive effects on consumer attitudes. Second, autonomous co-creation and sponsored co-creation are found to positively affect consumer attitudes. Third, consumers' intrinsic motivation has a fit-effect between upstream co-creation and autonomous co-creation, and their extrinsic motivation has a fit-effect between downstream co-creation and sponsored co-creation. Consumers who have strong intrinsic motivation are affected by upstream co-creation and autonomous co-creation. However, consumers who have strong extrinsic motivation are affected by downstream co-creation and sponsored co-creation. Conclusion - These results indicate that the fit between consumers' co-creation participation types and consumers'motivations is a significant factor in determining consumer attitudes. The results of this study imply that various types of consumer participation actually improve consumers' attitudes toward products and brands. In addition, our study also suggests that firms should consider the fit between co-creation types and consumers' motivations when they initiate co-creation activities. In this study, we survey consumers who participated in firms' co-creation activities. Future studies can compare different types of consumers. For instance, we can examine the different in different test by comparing experienced versus inexperienced consumers. Finally, we expand this research to user-generated content topics. This attending issue focuses on the mechanism that breaks down the boundaries and barriers between consumers and producers.

• Analytical Science and Technology
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• v.8 no.1
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• pp.55-62
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• 1995

Tetradentate Schiff base cobalt(II) complexes such as $Co(II)_2-N$, N-bis(salicylidene)-m-phenylendiimine; [$Co(II)_2(SMPD)_2(H_2O)_4$] and $Co(II)_2-N$, N-bis(salicylidene)-p-phenylendiimine: [$Co(II)_2(SPPD)_2(H_2O)_4$], and oxygen adducted cobalt (III) complexes such as [$Co(III)_2O_2(SMPD)_2(Py)_2$] and [$Co(III)_2O_2(SPPD)_2(Py)_2$] in pyridine solutions were synthesized. It was identified that the oxygen adducted cobalt(III) complexes have hexacoordinated octahedral configuration with pyridine and oxygen from the measurement of elemental analysis, AA, IR spectra, and TGA. The redox processes were investigated for the oxygen adducted complexes in 0.1M TEAP-pyridine solution, using cyclic voltammetry on the glassy carbon electrode. The redox processes of oxygen adducted Co(III) complexes result in $$[Co(III)_2-O_2-CO(III)]\rightarrow^{e^-}[Co(III)-O_2-Co(II)]\rightarrow^{e^-}[Co(II)-O_2-Co(II)]\rightleftarrows^{e^-}[Co(II)+Co(II)+O_2{\cdot}^-]\rightleftarrows^{e^-}[Co(II)+Co(I)+O_2{\cdot}^-]\rightleftarrows^{e^-}[Co(I)+Co(I)+O_2{\cdot}^-]$$.

• Journal of the Korean Chemical Society
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• v.31 no.6
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• pp.542-554
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• 1987

Tetradentate schiff base cobalt(II) complexes; Co(SED), Co(SND) and Co(SOPD) have been prepared, these complexes have react with dry oxygen in DMSO to form oxygen adducts cobalt(III) complexes; $[Co(SED)(DMSO)]_2O_2,\;[Co(SND)(DMSO)]_2O_2$ and $[Co(SOPD)(DMSO)]_2O_2$. It seems to be that the oxygen adducts cobalt(Ⅲ) complexes have heexa coordinated octahedral configration with tetradentate schiff base cobalt (III), DMSO and oxygen, and the mole ratio of oxygen to cobalt(II) complexes are 1 : 2, these complexes have been identified by IR-Spectra, T.G.A., magnetic susceptibilitis and elemental analysis of C.H.N. and Cobalt. The redox reaction process of Co(SED), Co(SND) and Co(SOPD) complexes was investigated by cyclic voltammetry with glassy carbon electrode in 0.1M TEAP-DMSO. The results of redox reaction process of Co(II) / Co(III) and Co(II) / Co(I) for cobalt(SED) and cobalt(SOPD) complexes and Co(II) / Co(III) process for cobalt(SND) complex are reversible process but Co(II) / Co(I) process of Cobalt(SND) complex is irreversible, and oxygen adduct complexes to quasi reversibly with oxygen should be very closed related to the redox potentials of range, $E_{pc}$ = -0.80~-0.89V and $E_{pa}$ = -0.70~-0.76V.