• Analytical Science and Technology
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• v.26 no.5
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• pp.315-325
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• 2013

The possibility of acute hepatotoxicity caused by dimethylformamide (DMF) requires regular monitoring of the workers who are using DMF to prevent the occupational disease. The authors performed ambient and biological monitoring of workers involved in synthetic leather manufacturing processes using DMF to assess the correlation between the markers of ambient and biological monitoring of DMF. The authors monitored 142 workers occupationally exposed to DMF from 19 workshops in the synthetic leather and ink manufacturing industries located in northern region of Gyeonggi-do. The subjects answered questionnaire on work procedure and use of personal protective equipment to be classified by exposure type. DMF in air samples collected using personal air samplers, diffusive and active sampler, was analysed using gas chromatograph-flame ionization detector (GC-FID) with DB-FFAP column (length 30 m, i.d. 0.25 mm, film thickness 0.25 ${\mu}m$). Urinary N-methylformamide (NMF) was analysed using gas chromatograph-mass selective detector (GC-MSD) at selected ion monitoring (SIM) mode with DB-624 column (length 60 m, i.d. 0.25 mm, film thickness 1.40 ${\mu}m$). Geometric mean (GM) and geometric standard deviation (GSD) of the ambient DMF was $6.85{\pm}3.43$ ppm, and GM and GSD of urinary NMF was $42.3{\pm}2.7$ mg/L. The ratio of subjects with DMF level over 10 ppm was 44%, and those with urinary NMF over 15 mg/L was 87%. NMF in urine adjusted by DMF in air was $4.61{\pm}2.57$ mg/L/ppm and $9.50{\pm}2.41$ mg/L/ppm, respectively, with or without respirator. There was seasonal differences of NMF in urine adjusted by DMF in air, $7.63{\pm}2.74$ mg/L/ppm in summer and $4.53{\pm}2.29$ mg/L/ppm in winter. The urinary NMF concentration which corresponds to 10 ppm of ambient DMF was 52.7 mg/L (r=0.650, n=128). Considering the difference of the route of exposure which resulted from the compliance of wearing personal protective equipment, the estimated contribution of respiratory and dermal exposure route for DMF was 48.5% vs. 51.5%.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.202-210
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• 1983

In order to elucidate the taste compounds of Korean catfish, Parasilurus asotus, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals in the extracts of Korean catfish were analyzed, and then evaluated by sensory test of synthetic extract prepared on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. In free amino acid composition, glycine was dominant occupying $25\%$ of total free amino acids. The other abundant free amino acids were lysine, taurine and alanine. Judging from the result of analysis of nucleotides, IMP was dominant showing about $70\%$ of total nucleotides while ATP, ADP, AMP, inosine and hypoxanthine were low in content. Among organic bases, total creatinine was abundant and its nitrogen content occupied more than $50\%$ of the total extractive nitrogen. The amount of betaine was 18mg/100g and trace amount of trimethylamine and trimethylamine oxide were detected. The main organic acids were succinic, butyric, propionic and valeric acid. On the other hand, oxalic, fumaric, maleic, tartaric and citric acids were analyzed in trace. As for the sugars, glucose was found to be the most abundant monosaccharide. Extremely small amounts of fructoae, inositol were also detected and ribose and arabinose were trace in content. $K^+,\;Na^+,\;PO_{4}^{3-}$ and $Cl^-$ were found to be the major ions and small amount of $Ca^{2+}$ were defected. The synthetic extract, prepared with about 40 pure chemicals based on the analytical data satisfactorily revealed the natural taste of the original extract except slight difference in meaty taste and mildness. From the results of omission test the major components which contribute to produce the taste were serine, IMP, succinic acid and $PO_{4}^{3-}$.

• Journal of the Health Care and Life Science
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• v.9 no.1
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• pp.141-146
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• 2021

Determination of capsaicin, dihydrocapsaicin and nonivamide in pungent liquids of self-defense spray were studied. The nonivamide having almost same spicy taste with capsaicin have been containing a few amounts in natural products, it had called as synthetic capsaicin or PAVA, have used to flavorings for foodstuffs and incapacitating agents of riot controls. Nowadays, it has been occasionally found that the quality controls of a self-defense sprays were not properly due to flood of illegal self-defense sprays. Thus, the simple analytical method with gas chromatography is developed, it is identified whether the products which have contained synthetic capsaicin were marked like natural materials as well as the pungent ingredients in it obeyed with permissible concentration to human or not was investigated. Finally, the pungent components and amounts in some kinds of self-defense spray were investigated.

• Journal of the Korea Society for Simulation
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• v.19 no.4
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• pp.235-247
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• 2010

An environmental factor is very important in a war game model supporting military training. Most war game models in Korean armed forces apply the same weather conditions to all operation areas. As a result, it fails to derive a high-fidelity simulation result. For this reason this study attempts to develop factor techniques for a high-fidelity war game that can apply distributed synthetic atmospheric environment modeling data to a military simulation. The major developed factor technology of this study applies regional distributed precipitation data to the 2D-GIS based Simplified Detection Probability Model(SDPM) that was developed for this study. By doing this, this study shows that diversely distributed local weather conditions can be applied to a military simulation depending on the model resolution from theater level to engineering level, on the use from training model to analytical model, and on the description level from corps level to battalion level.

• 보존과학연구
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• s.22
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• pp.93-114
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• 2001

The composition analysis of Danchung pigments at Geunjeongjeon Hall in Gyeongbokgung Palace were carried out by FXRF and MXRD. The analytical result of the inside pigments at Geunjeongjeon showed that these painted in use the mineral pigments. Gold pigment was pure gold(Au).The main composition identified in green pigments were chalcanthite($CuSO_4$.$5H_2O$) and celadonite($K(Mg, Fe, Al)_2$.$(Si, Al)_4O_10(OH)_2$ ). Red pigments werecinnnabar(HgS).The analytical result of the outside pigments at Geunjeongjeon revealed that these applied to the artificial synthetic pigment. Yellow pigment was chromeyellow($PbCrO_4$). The main composition identified in red pigments were red lead($Pb_3O_4$)and hematite($Fe_2O_3$). Green pigments were emeral green($C_2H_3A_s3Cu_2O_8$) and chromegreen($Cr_2O_3$). Blue pigment was lazurite($Na_6Ca2Al_6Si_6O_24(SO_4)_2$), titanium dioxide($TiO_2$) of white pigment.

• Analytical Science and Technology
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• v.7 no.1
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• pp.41-52
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• 1994

The importance of separation comes from demands on study for exact effect of synthetic drugs and the reactivity of enantiomer in biological system. Racemization rate was measured under the influence of heat, acid, UV-light, enzyme(trypsin) and 6N-HCl at $105^{\circ}C$ on alanine, threonine, isoleucine, lecuine, aspartic acid, methionine, glutamic acid, tyrosine. The method for the identification of overlapped amino acids with GC was developed from the close study of fragmentation pattern with mass spectrometry. With cyclodextrin bonded phase by HPLC, the separation of dansyl amino acid was tested for compartison.

• Analytical Science and Technology
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• v.10 no.4
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• pp.291-299
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• 1997

2,2'-iminodibenzoic acid-cellulose was prepared by reacting 2,2'-iminodibenzoic acid salt with cellulose-Cl obtained by chlorination of cellulose-OH which is the major component of sawdust. The adsorptivity of Pb(II) and Cu(II) was studied using the synthetic chelating adsorbent. The adsorption amounts of those ions increased with increasing pH and the optimum adsorption time of metal ion was about 1hr. The adsorptivity of Pb(II) was larger than that of Cu(II).

• Analytical Science and Technology
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• v.5 no.1
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• pp.33-39
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• 1992

THF-based crown-4 of 16-membered rings having tetrahydrofuran unit was synthesized by an acid-catalyzed condensation of furan and acetone followed by hydrogenation in an effort to obtain highly elective ionophores for lithium ions. The new ionophore was compared with previously reported ionophores under similar measurement conditions with the same plasticizer, tris(2-ethylhexyl) phosphate in poly(vinyl chloride)(PVC) membrane electrodes. Separate solution method was used to determine relative selectivity coefficients for the electrode. The selectivity coefficients($K_{LiM}^{POT}$) of lithium over ammonium, alkali and alkaline earth metal ions go from about $2.4{\times}10^{-1}$ to $2.3{\times}10^{-4}$ to working range and pH dependence have also been studied.

• Analytical Science and Technology
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• v.10 no.6
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• pp.433-438
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• 1997

The enhancing effect of n-octanol on the fluorescence intensity of the $Eu^{3+}$-thenoyltrifluoroacetone(TTA) system in the presence of Triton X-100 was studied using spectrofluorometric method. This complex exhibited very intense $Eu^{3+}$ ion fluorescence at 619nm, when optically excited at 345nm. Optimum conditions for the determination of n-octanol have also been investigated. The calibration graph was linear over the range $1{\times}10^{-5}M{\sim}1{\times}10^{-7}M$ and the detection limit for n-octanol is $1{\times}10^{-9}M$. The result obtained in the analysis of the synthetic sample agreed with the known value in the error range and the relative standard deviation was ca. 3.5%.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.197-204
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• 2020

Nowadays, many construction engineering and technology enterprises are evolving to find that prosperity is driven and inspired by an open economy with dynamic markets and fierce multifaceted competition. Besides brand and product uniqueness, the ability to quickly provide customers with quotes are matters of concern. Such a requirement for prompt cost estimation of construction investment projects with the use of a construction price index poses a significant challenge to contractors. This is because the nature of the construction industry is shaped by changes in domestic and foreign economic factors, socio-financial issues, and is under the influence of various micro and macro factors. This paper presents a fuzzy decision-making approach for calculating critical factors that affect the construction price index. A qualitative approach was implemented based on in-depth interviews of experts in the construction industry in Vietnam. A synthetic comparison matrix was calculated using Buckley approach. The CoA approach was applied to defuzzified the fuzzy weights of factors that affect the construction price index. The research results show that the top five critical factors affecting the construction price index in Vietnam are (1) consumer price index, (2) gross domestic product, (3) basic interest rate, (4) foreign exchange rate, and (5) total export and import.