• Journal of Preventive Medicine and Public Health
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• v.4 no.1
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• pp.41-64
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• 1971

During the period from July 1st to the end of November 1970, a survey on air pollution and noise level was made in Seoul, Pusan and Taegu, the three largest cities in Korea. Each city was divided into 4-6 areas; the industrial area, the semi-industrial area, the commercial area, the residential area, the park area and the downtown area. Thirty eight sites were selected from each area. A. Method of Measurement : Dustfall was measured by the Deposit Gauge Method, sulfur oxides by $PbO_2$ cylinder method, suspended particles by the Digital Dust Indicator, Sulfur dioxide ($SO_2$) and Carbon Monoxide (CO) by the MSA & Kitakawa Detector and the noise levels by Rion Sound Survey meter. B. Results: 1. The mean value of dustfall in 3 cities was $30.42ton/km^2/month$, ranging from 8.69 to 95.44. 2. The mean values of dustfall by city were $33.17ton/km^2/month$ in Seoul, 32.11 in Pusan and 25.97 in Taegu. 3. The mean values of dustfall showed a trend of decreasing order of semi-industrial area, downtown area, industrial area, commercial area, residential area, and park area. 4. The mean value of dustfall in Seoul by area were $52.32ton/km^2/month$ in downtown, 50.54 in semi-industrial area, 40.37 in industrial area, 24,19 in commercial area, 16.25 in park area and 15.39 in residential area in order of concentration. 5. The mean values of dustfall in Pusan by area were $48.27ton/km^2/month$ in semi-industrial area, 36.68 in industrial area 25.31 in commercial area, and 18.19 in residential area. 6. The mean values of dustfall in Taegu by area were $36.46ton/km^2/month$ in downtown area, 33.52 in industrial area, 20.37 in commercial area and 13.55 in residential area. 7. The mean values of sulfur oxides in 3 cities were $1.52mg\;SO_3/day/100cm^2\;PbO_2$, ranging from 0.32 to 4.72. 8. The mean values of sulfur oxides by city were $1.89mg\;SO_3/day/100cm^2\;PbO_2$ in Pusan, 1.64 in Seoul and 1.21 in Taegu. 9. The mean values of sulfur oxides by area in 3 cities were $2.16mg\;SO_3/day/100cm^2\;PbO_2$ in industrial area, 1.69 in semi-industrial area, 1.50 in commercial area, 1.48 in downtown area, 1.32 in residential area and 0.94 in the park area, respectively. 10. The monthly mean values of sulfur oxides contents showed a steady increase from July reaching a peak in November. 11. The mean values of suspended particles was $2.89mg/m^3$, ranging from 1.15 to 5.27. 12. The mean values of suspended particles by city were $3.14mg/m^3$ in Seoul, 2.79 in Taegu and 2.25 in Pusan. 13. The mean values of noise level in 3 cities was 71.3 phon, ranging from 49 to 99 phon. 14. The mean values of noise level by city were 73 phon in Seoul, 72 in Pusan, and 69 in Taegu in that order. 15. The mean values of noise level by area in 3 cities showed a decrease in the order of the downtown area, commercial area, industrial area and semi-industrial area, park area and residential area. 16. The comparison of the noise levels by area in 3 cities indicated that the highest level was detected in the downtown area in Seoul and Taegu and in the industrial area in Pusan. 17. The daily average concentration of sulfur dioxides ($SO_2$) in 3 cities was 0.081 ppm, ranging from 0.004 to 0.196. 18. The daily average concentrations of sulfur dioxides by city were 0.092 ppm in Seoul, 0.089 in Pusan and 0.062 in Taegu in that order. 19. The weekly average concentration of carbon monoxides(CO) was 27.59 ppm. 20. The daily average concentrations of carbon monoxides by city were 33.37 ppm. in Seoul, 25.76 in Pusan and 23.65 in Taegu in that order. 21. The concentration of $SO_2$ and CO reaches a peak from 6 p. m. to 8 p. m. 22. About 3 times probably the daily average concentration of CO could be detected in the downtown area probably due to heavy traffic emission in comparison with that in the industial area. 23. As for daily variation of the concentration of $SO_2$ and CO it was found that the concentration maintains relatively higher value during weekdays in the industrial area and on the first part of the week in the downtown area.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.238-245
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• 2001

Optimal conditions for processing. of seasoned-dried Pacific saury treated with liquid smoke (T2) were evaluated by physicochemical and microbial experiments and sensory evaluation, comparing with control (seasoning only, C) and treatment I $(0.05\%\;Rosemary\;instead\;of\;liquid\;smoke,\;Tl)$. Two hrs of seasoning time was set, and 23 hrs of drying time was determined in all samples. Finally, T2 product was made by soaking treatments (three times of 1 sec, 8 sec and 1 sec) in $5\%$ (v/v) liquid smoke (Scansmoke PB 2110) after 30 min, 4 hrs and 22 hrs of hot-air drying, respectively. The histamine contents in 3 seasoned-dried products were in a 15.33-26.99 mg/l00g range. The water activities of 3 seasoned-dried products were 0.719-0.735 range, and the pH of T2 was lower than the others. In the comparison of POV and TBA values among products, the TBA values and POV of Tl and T2 were significantly low compared to C, and also the viable cell counts of T2 was relatively lower than those of the others. In the color values, significant changes were not found among products, and in the sensory evaluation for odor, taste and overall acceptance, T2 had relatively higher preference on the whole items.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.12
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• pp.943-948
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• 2012

A new water energy harvester module, which is composed of piezoelectric bimorph cantilevers, harvesting circuit and a shaft with 16 impellers at a center axis, was fabricated for energy harvesting application. High energy density $Pb(Zr_{0.54}Ti_{0.46})O_3$ + 0.2 wt% $Cr_2O_3$ + 1.0 wt% $Nb_2O_5$ (PZT-CN) thick film obtained by tape casting method was used for the bimorph cantilever. The PZT-CN bimorph cantilever with a proof mass of 49 g exhibited extremely high output power of 22.5 mW (24 $mW//cm^3$) at resonance frequency of 11 Hz. In addition, the fabricated water energy harvester has a cylindrical structure with 48 bimorph cantilevers clamped at inner surface. A significantly high output power of 433 mW was obtained at a rotation speed of 120 rpm with a resistive load of $500{\Omega}$ for the water energy harvester.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.5
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• pp.697-711
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• 2004

Severe haze, mist, and fog phenomena occurred in the central part of Korea during 15~25 May 2003 resulted in poor visibility and air quality. When these phenomena occurred, Korean peninsula was under the effects of anticyclone. The atmosphere was stable, and wind speed was so weak. Under this meteorological conditions, air quality was worse and worse. The characteristics of aerosol in Seoul, Incheon, and Gosan (Jeju) during this period are investigated from the $PM_{10}$. TSP concentrations and aerosol number concentrations. Concentrations of $PM_{10}$ and TSP measured at KMA increased upto 176 and 230 J.${\mu}g/m^3$ on 22 May 2003, respectively. Aerosol number concentrations of size range from 0.82 to 6.06 ${\mu}m$ increased in Seoul on 17, 19, and 21~24 May 2003, and the concentrations of $NO_2$ and $SO_2$had maximum value of 0.165 ppm at Gwanak Mt. and 0.036 ppm at Guro-dong on 23 May 2003, respectively. Result from analysis on heavy metal elements showed high concentrations of Zn, Pb, Cr, Ni, Cu, and Cd during 20~24 May 2003. This event is examined by comprehensive analyses of synoptic weather conditions, satellite images, concentrations of suspended particles and air pollutants, and heavy metal elements.

• Journal of Environmental Science International
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• v.13 no.5
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• pp.479-488
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• 2004

Five sediment cores from the tidal flat of artificial Lake Shihwa are analyzed in terms of sedimentology and geochemistry to evaluate the heavy metal contamination and redox condition of surficial sediment following the Shihwa seawall construction. The variability of concentrations of various elements depends on the depositional environment, and reflects the various redox conditions and sediment provenances. The amounts of Ti and Al and their ratio of Ti/ Al with respect to Li clearly indicate that there is an anthropogenic contribution to the surficial sediment. The high concentrations of heavy metals suggest an anthropogenic contribution at ST. 34 and ST. 22. Concentrations of most elements (Cr, Cu, Zn and Pb) are higher near the Shihwa-Banwol industrial complex than in the central part of Lake Shihwa. Concentrations of heavy metal in surficial sediment near the Shihwa-Banwol industrial complex are two to eight times higher than in the center of Lake Shihwa. Enrichment factors (EF), which are normalized by the unpolluted shale, suggests a significant metallic contamination near the Shihwa-Banwol industrial complex (SBIC). The redox condition is divided into two anoxic and mixed oxi $c_oxic zones based on the carbon:sulfur (C/S) ratios of organic matter and elemental relationships. Correlations among geochemical elements Mn, U and Mo are significantly different from site to site, and may therefore be an indicator of the spatial redox condition. Controlling factors for switching anoxic/oxic conditions are thought to be water depth and the differences in industrial effluent supply. The variations of the Cu/Mn ratio in the sediments confirms above mentioned spatial differences of a redox condition in part, and therefore shows a location-dependence redox condition in sediments at four other sites. The redox condition of the surficial sediment characteristics of the Shihwa Lake are controlled by its geographic location and water depth.th.

• Journal of Environmental Science International
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• v.26 no.6
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• pp.797-802
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• 2017

This study aimed to remove organic matter and heavy metals that could affect the recycling of soils contaminated by heavy metals, by means of electrolysis, carried out simultaneously with the leaching of the soil. To ensure better experimental equipment, a soil electrolysis apparatus, equipped with spiral paddles, was used to agitate the heavy-metal-contaminated soil effectively. The heavy-metal-contaminated soil was electrolyzed by varying the voltage to 5 V(Condition 1), 15 V(Condition 2), and 20 V(Condition 3), under the optimal operating conditions of the electrolysis apparatus, as determined through previous studies. The results showed that the pH of the electrolyte solution and the heavy-metal-contaminated soil, after electrolysis, tended to decrease with an increase in voltage. The highest removal efficiencies of TOC and $COD_{Cr}$ were 18.8% and 29.1%, 38.8% and 4.2%, and 33.3% and 50.0%, under conditions 1, 2 and 3, respectively. Heavy metals such as Cd and As were not detected in this experiment. The removal efficiencies of Cu, Pb and Cr were 4.7%, 8.3% and 2.1%, respectively, under Condition 1, while they were 42.9%, 15.2% and 22.1%, respectively, under Condition 2, and 4.7%, 23.0%, and 24.9%, respectively, under Condition 3. These results suggest that varying the voltage with the soil electrolysis apparatus for removing contaminants for the recycling of heavy-metal-contaminated soil allows the selective removal of contaminants. Therefore, the results of this study can be valuable as basic data for future studies on soil remediation.

• Journal of Environmental Health Sciences
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• v.2 no.1
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• pp.37-48
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• 1975

Air pollutants were measured to get useful data in preventing and controlling the pollution at industrial and semi-industrial, commercial, cross-road and residential areas by season in Busan from September 1973 to June 1974. Teated were dustfalls(ton/$km^2$/month)by Deposit Gauge method, sulfuric anhydride(mg $SO_3/day/100cm^2 PbO_2$) by Lead Peroxide candle method. The relations between pollution and metherologlcal factors and source of pollution were discussed, The findings are as follows: 1. The mean value of dustfalls was 24.8 tons rangi~ng from 12.5 tons to 44.5 tons. The highest amount of dustfalls of 29.0 tons was measured in crossroad areas while the 1oeest of 22.7 tons in commercial areas, and Winter the highest of 27.7 tons while in Spring the lowest of 21.2 tons. 2. The mean value of water soluble substances was 31.7 per cent, and seasonal variation of pH was shown as 4.20 in Autumn, 3.85 in Summer and 2.76 in Winter. 3. The mean value of sulfuric anhydride was 1.54mg ranging from 0.197mg to 4.162 mg. The highest concentration of sulfuric anhydride of 2.03mg was detected in cross-road areas while thelowest of 1.23mg in residential areas, and Summer the highest of 2.18mg while in Spring the lowest of 1.09mg(0. 92mg in Nov. 1973) 4. Dustfalls are more with the decreased of relative humidity and precipitation while concentrat:on of sulfuric anhydrides are more with the increased of relative humidity. 5. There is a probability of occuring chronic symptoms(respiratory and others) as the dustfalls with 24.8 tons and sulfuric anhydride with 1.54mg in Busan. According to this, it is the time to discuss monitoring system and systematic preventing methods.

• The Research Journal of the Costume Culture
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• v.19 no.3
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• pp.612-621
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• 2011

The process of making or cultivating indigo dyes is very cumbersome and complex. The dye extraction and dyeing methods using general plant dye, moth repellent dye, fast acting natural dye, and other dyes are very different. This research investigates the extraction of indigo dye and liquid dye extraction of polygonum(indigo) plants using calcium oxide water. While extracting indigo dye the concentration of purified indigo dye may be controlled by adjusting the pH level. Due to the various uses of dyes the adjustment of surface color must be considered. In regard to the change according to different concentrations of reducing agents, it was found that cotton fabrics and ramie fabrics show the highest color difference at 0.4% and 0.3% respectively. As the reduction temperature increases, the color difference increases as well. The maximum color difference was found to appear at $90^{\circ}C$. Cotton fabrics and ramie fabrics showed 70.55 and 67.01 respectively. The color difference increases as the concentration of dyes increases, but at a concentration of 300%, cotton fabrics was found to show 6.22PB in H value using the Munsell color system, containing purple and blue color. The pH of the polygonum dyes extracted through this experiment were adjusted by adding calcium oxide to the experimental water, without directly adding calcium oxide to the liquid polygonum extract. In a refine state, it was mixed with polygonum extract to extract a more refine and highly concentrated indigo dye. When lye and reducing agents are added to extracted indigo dye and sealed for long-term storage, it can be effective and easily used for dyeing.

• Journal of the Korean Wood Science and Technology
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• v.29 no.1
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• pp.22-30
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• 2001

Composites with various layer constructions involving the ratio of S/P were produced from wood strands(S) and particles(P) (Cryptomeria japonica D.Don) to measure various Young's moduli and anisotropy by ultrasonics. As a result, static Young's moduli of composites were almost same as dynamic Young's moduli obtained from natural frequency. However, these were smaller than those evaluated from ultrasonic wave propagation velocity. The differences between propagation velocity of the parallel(${\parallel}$) and perpendicular(${\bot}$) in-plane direction resulted in a tendency of anisotropy. The tendency of anisotropy was larger in three-layer constructions than in seven-layer constructions. The differences of strand surface layers showed larger values than those of particle surface layers. Also, composites with higher weight ratio of strand had a tendency to propagate rapidly in each direction. In contrast to these results, the propagation velocity in the thickness direction had a tendency to propagate rapidly in composites with particle surface layers and the lower weight ratio of strand.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.209-213
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• 2012

The propolis was collected from the whole part of Korea Peninsula, such as central, southern, and Jeju island, to analyze the general composition including total flavonoid and phenolic contents, heavy metals, colors, amino acids, and crude lipid. The total flavonoid and phenolic contents of middle region in Korea Peninsula (4.26% and 13.06 g/100 g gallic acid) were higher than southern region (2.53%, 10.9 g/100 g gallic acid) and Jeju island (0.03%, 7.22g/100 g gallic acid), respectively. The heavy metals contents showed that Zn contents were found in $0.44{\pm}0.2ppm$ and a harmful heavy metal such as Cr, Cd, Pb, Ni, Cu, As, and Hg were not detected at all in our experiment. The colors of extracted propolis showed a various spectrum from yellow to red purple. Various amino acids were also detected as proline, valine, methionine and the average crude lipid contents of propolis were 42.4%. All data collected in South Korea were very first executed in our institution for the purposes of utilizing and developing the industrial insects, honeybees as well as silkworm.