• Journal of Environmental Impact Assessment
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• v.6 no.1
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• pp.105-110
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• 1997

Sanitary landfill is a general method as a final disposal of municipal solid waste(MSW), therefore leachate characteristics are very various as lime goes by because of highly concentrated organic acids are contained non biodegradable COD. So it is hard to abide by the mandatory standards of discharge eventhough applying the physicochemical and biological processes to treat the leachate. The process of treating leachate are determined by the degree of removal and components, but they are highly contained organic materials. It is a removal method to use jointly with the physicochemical process if the hard and fast rule is needed. The critical components of material are COD, ammonia, salts and heavy metals in the case of treating biologically. Biological process is to use metabolism of microorganism, therefore it is a desirable condition which heavy metals are not contained, because they acting as an inhibitor of enzyme. Of these are contained, organic decomposition and synthetic function of microorganisms decrease significantly. Consequently, this research paper lays emphasis on the concentration of heavy metals in leachate and for the purpose of forecasting the factors which are affecting the leaching of metalic waste in some degree, experimented the various reacting conditions. 1. When the concentration of heavy metals in leachate is in comparison with the level eluted after reaction, at pH 7.9 the result of reaction for PCB to CCL scrap showed that Zn, Mn, Cu was more eluted 11.6 times, 340.3 times, and 2,705.5 times respectively than the leachate undiluted solution. 2. At the condition of strong acid pH 4.7, the concentration of heavy metals in EM undiluted solution showed that Zn, Mn, Cu was more eluted 26.5 times, 147.3 times, and 3,656.3 times respectively than leachate undiluted solution. 3. When the ratio leachate to EM was 50 vs 50(V/V%), Mn was more eluted 198.7 times than leachate undiluted solution, but Zn and Cu do not show the meaningful results. 4. The color of landfill leachate was black-brown. And fulvic acid that is main ingredient of NBD COD contained, oxygen of 44~50%. For that reason, I estimated that the level of Zn, Mn, Cu was higher than the case of leachate. 5. COD of leachate from general landfill is difficult to remove. Because the solution of heavy metals is improved by the character of leachate(pH & ingredient of oxygen etc.) hence the Mn, Cu, Zn act as disturbing factor, the biochemical treatment is hard. Therefore the type of PCB & CCL scrap, iron, aluminum contained metals need to previously separate from general wastes as much as possible.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1148-1152
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• 2008

Molten carbonate oxidation (MCO) is one of the promising alternative technologies for the treatment of the chlorinated organic compounds because it is capable of trapping chlorine during a destruction of them. In this study, destructions of chlorinated organic compounds ($C_6H_5Cl$, $C_2HCl_3$ and $CCl_4$) and an insulated oil containing PCBs were performed by using the two stage molten carbonate oxidation system. MCO reactor temperature largely affected the destruction of the chlorinated organic compounds. Destruction of the chlorinated organics very efficient in the primary MCO reactor however a significant amount of CO was emitted from the MCO system. This CO emission was gradually decreased by an increase in the primary reactor temperature and oxidizing air feed rate. The HCl emission from the MCO system was below 7 ppm regardless of tested conditions. The chlorine collection efficiencies were in the range of 99.95-99.99%. The destruction of PCBs in the insulated oil was efficient at a temperature above $900^{\circ}C$ and overall destruction efficiency of them was determined as over 99.9999%.

• Solar Energy
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• v.15 no.2
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• pp.65-75
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• 1995

We have summarised some important aspects of our recent basic and applied studies in the area of photocatalytic detoxifcation with Degussa P25 titanium dioxide($TiO_2$) being the photocatalyst. Heterogeneousphotocatalytic decompositions of two components such as TCE-chloroform, TCE-phenol and TCE-benzene as well as single component organic, TCE, chloroform and $CCl_4$ were carried out to investigate the effect of additional compound on the TCE decomposition rate. In laboratory experiments, the optimum flow rate of TCE solution was $200cm^3/min$ with annular photoreactor in the presence of 0.1 wt% $TiO_2$ powder under illumination. It was observed that the second compound such as $CHCl_3$, phenol and benzene has a negative effect on the TCE decomposition rate. Result presented that TCE decomposition ratio was increased at low pH in the TCE-phenol two component solution. It could be shown that the photocatalytic reactor exhibits technical feasibility of detoxifying the multicomponent under proper experimental conditions.

• Journal of the Korean Society for information Management
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• v.37 no.4
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• pp.255-286
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• 2020

This study aims to identify the methods of implementation for the 'National Research Foundation of Korea Open Access 2021(Plan)'. This study covers the methods of implementation in the three following core items: 1) developing the details on the amount, method, and procedures of APC support; 2) proposing methods for facilitating the transition of domestic Korean academic journals to open access journals; and 3) developing methods of entrusting papers to open access repositories. APC support should be guaranteed at a reasonable level. The average or median of APC values for the previous three years will be applied to set the upper limit for support each year. APC support will be provided when the paper is published to open access journals or transitioning journals to open access. Hybrid journals or dual access journals are not included. Support for open access publishing of academic journals in Korea during the transition period will be available for open access journals that have registered for CCL in KJCI or journals that have submitted their application for transitioning to open access. Publishing in hybrid, dual access or subscription-based journals must be accompanied by items related to copyright such as embargo. Research results will be used for the detailed implementation plan of 'NRF OA2021 (Plan)'. They will serve as the base data for the rapid, stable, and sustainable implementation of open access policy in NRF, addressing the Korean domestic academic journal publishing environment and the field of international academic communication.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.2
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• pp.271-291
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• 2023

The purpose of this study is to analyze the current status and effects of open access conversion of journals from 7 societies that participated in the "Open Access Publication Declaration Academic Societies in the Field of Library and Information Science", and to identify problems and suggest improvement directions. To this end, the study analyzed the current status based on the elements presented in the "Roadmap for Open Access Publishing Conversion of the Library and Information Science Journals in Korea" and analyzed citation rates. The following problems were identified. First, some journals were not applying CCL or were unable to register it accurately with KJCI, and none of the 7 journals were registered with DOAJ. Second, the newly used journal platforms had not yet registered all previous issues after the conversion. Third, there was a tendency for the article processing charges to be partially increased, and there was also a tendency for editorial staff expenses to increase. Fourth, citation indexes after conversion were lower for both journals compared to the previous 4-5 years. This study proposes that joint publication of journals is necessary to solve practical problems jointly with societies while promoting economies of scale and suggests the need for further development of a roadmap.

• The Journal of the Acoustical Society of Korea
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• v.26 no.4
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• pp.159-165
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• 2007

In this paper, we propose a new pre-selection of candidate units that is suitable for the unit selection based Japanese TTS system. General pre-selection method performed by calculating a context-dependent cost within IP (Intonation Phrase). Different from other languages, however. Japanese has an accent represented as the height of a relative pitch, and several words form a single accentual phrase. Also. the prosody in Japanese changes in accentual phrase units. By reflecting such prosodic change in pre-selection. the qualify of synthesized speech can be improved. Furthermore, by calculating a context-dependent cost within accentual phrase, synthesis speed can be improved than calculating within intonation phrase. The proposed method defines AP. analyzes AP in context and performs pre-selection using accentual phrase matching which calculates CCL (connected context length) of the Phoneme's candidates that should be synthesized in each accentual phrase. The baseline system used in the proposed method is VoiceText, which is a synthesizer of Voiceware. Evaluations were made on perceptual error (intonation error, concatenation mismatch error) and synthesis time. Experimental result showed that the proposed method improved the qualify of synthesized speech. as well as shortened the synthesis time.

• Bulletin of the Korean Chemical Society
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• v.26 no.10
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• pp.1525-1528
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• 2005

The synthesis and characterization of ${K_3[Ru(C_2O_4)3]{\cdot}4H_2O\;(C_2O_4}^{2-}$ = oxalato anoin) complex are described, and its redox properties (in buffer solution of pH = 12) have been investigated. This complex is used for in situ generation of oxoruthenates complexes which have been characterized by electronic spectroscopy. Reaction of ${K_3[Ru(C_2O_4)3]{\cdot}4H_2O$ with excess ${S_2O_8}^{2-}$ in molar KOH generates trans-${[RuO_3(OH)_2]^{2-}/S_2O_8}^{2-}$ reagent while with excess ${BrO_3}^-$ in molar $Na_2CO_3$ generates ${[RuO_4]^-/BrO_3}^-$ reagent. Avoiding the direct use of [$RuO_4$] the organic-soluble $(n-Pr_4N)^+[RuO_4]^-$, (TPAP) has been isolated by reaction of $K_3[Ru(C_2O_4)3]{\cdot}4H_2O$ with excess ${BrO_3}^-$ in molar carbonate and n-$Pr_4$NOH. In a mixture of $H_2O/CCl_4$ ruthenium tetraoxide can be generated by reaction of $K_3[Ru(C_2O_4)3]{\cdot}4H_2O$ with excess ${IO_4}^-$. The catalytic activities of oxoruthenates that have been made from $K_3[Ru(C_2O_4)3]{\cdot}4H_2O$ towards the oxidation of benzyl alcohol, piperonyl alcohol, benzaldehyde and benzyl amine at room temperature have been studied.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.4
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• pp.805-815
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• 1994

The development of automatic production systems has a trend toward Computer Integrated Manufacturing System(CIMS) in recent years. In hardware configuration, CIMS are composed of intelligent CAD/CAM work stations, multifunction CNC machining centers including material handling systems. The DNC systems present the key element of automation hierarchy in a FMS. A DNC system is one which connects a number of numerically-controlled machines to a common memory in a digital computer for part program storage with provision for on-demand distribution of part program data to machines using communication in hierarchical structure of central computer, control computer and cell controller. This paper describes the development of Behind-the-Tape-Reader(BTR) type DNC system using CYBER 180-830 as a central computer and IBM PC-386 cell control computer and NC lathe with FANUC 5T NC controller. In this system, the connection between central computer and cell control computer is done via RS-232C serial interface board, and the connection between cell control computer and FANUC 5T controller is done via parallel interface board. The software consists of two module, central computer communication module for NC program downloading and status uploading, NC machine running module for NC operating.

• Advances in Traditional Medicine
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• v.9 no.3
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• pp.252-258
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• 2009

Shade-dried flowers of Sarcostemma brevistigma Wight Syn (SBF) belonging to Asclepiadaceae yielded a rare flavonol glycoside viz., Quercetin 5a prenyl, 3-O-glucosyl, 7-O-(4c-p-coumaroyl) neohesperidoside which were characterized based on chemical and spectral (including 2D NMR) studies. The ethyl acetate fraction of alcoholic concentrate (test sample) of flowers of this plant (SBF) was evaluated for its hepatoprotective and inhibition of lipid peroxidation activities to investigate the scientific basis of the traditional uses. The oral administration in varying doses viz., 125 and 250 mg/kg of aqueous suspension of SBF to rats for 7 days produced significant (P < 0.01) hepatoprotective effect comparable to that of standard drug silymarin. The SBF afforded good hepatoprotection against $CCl_4$ induced elevation levels of serum marker enzymes, serum bilirubin and liver weight. The free radical scavenging effects of SBF and flavonol glycoside (SA) were assigned by $Fe^{2+}$/ascorbate induction method (in vitro), which revealed the inhibition of lipid peroxidation. The SBF and SA showed prominent anti-lipid peroxidation activity ($IC_{50}$ about $\sim$180 mg/ml and 11.0 mg/ml respectively), which was comparable to standard drug curcumin ($IC_{50}$ about $\sim$8.25 mg/ml). Thus the hepatoprotective activity of SB could be correlated to the free radical scavenging property of the flavonol glycoside.

• Journal of the Korean Chemical Society
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• v.11 no.4
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• pp.143-149
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• 1967

The Transient State Theory of Significant Liquid Structure is applied to a binary liquid solution of benzene and carbon tetrachloride, which gives slightly positive deviation from Raoults law. The partition function for the solution is derived according to the proposed theory. The various thermodynamic properties such as total and partial vapor pressures, molar volumes, entropies of mixing, and compressibilities are calculated at three different temperatures, 298.15^{\circ}K$, 313.15^{\circ}K$ and 343.1515^{\circ}K$. The calculated values agree satisfactorily with experimental data.