• Journal of Preventive Medicine and Public Health
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• v.32 no.2
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• pp.113-122
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• 1999

Objectives: The purpose of this study was to describe the trends of original research in the Korean Journal of Preventive Medicine, and to evaluate the quality of original articles about lead poisoning. Method: The data for the analysis of trends in preventive medicine research was taker from a total of 829 original articles published in the Korean Journal of Preventive Medicine from 1968 to 1997, The qualitative meta-analysis was measured against a checklist of evaluation criteria, which were divided into 10 categories, with 46 articles on lead poisoning. The evaluation process was performed independently by two evaluators, Results: The number of articles per 100 members over the study period increased by almost 4 pieces in the early 1980s, and by more than 9 pieces in the mid-1990s. In the major classifications of subjects, environmental and industrial health, epidemiology and health statistics, and health policy and management published 370 pieces (44.0%), 137 pisces (16.5%), 322 pieces (38.9%) respectively. In the order of the number of articles, five themes about health significance, including metal exposure (73 pieces), diseases associated with exposure to organic solvents (45 pieces), air pollution (36 pieces), maternal and child health (32 pieces), and occupational health (3D pieces) received consistent attention throughout the years $1968\sim1997$. The overall mean score of article qualify about lead poisoning was 37.8 out of 50. Of the articles any information on the purpose and hypothesis described well, Of those the originality of the subjects, the form of article's (including tables and figures), and the number of inappropriate words of abstracts showed very low score. For multiple regression analyses, the number of joint research institutes and the acceptance of research grants about the article quality were statistically significant. Conclusions: The number of original research reports in the Korean J Prev Med has recently increased and their subjects bave diversified. Of the basis of this study, the articles need improvement in the areas of abstracts, tables and illustrations (figures), etc. The Korean Society for Preventive Medicine will revise contribution regulations for manuscripts submitted to the Korean J Prev Med. Future studies should address these issues and perform the quantitative mata-analysis about the specific subjects including the quality of articles.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.302-309
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• 2013

The highly porous cellulosic aerogels were prepared by freeze-drying method using sodium hydroxide-urea aqueous solution in the process of dissolution, gelation, regeneration and organic solvent substitution. The structural characteristics of porous aerogel were analyzed using scanning electron microscopy and nitrogen adsorption apparatus. As a result, the dissolving pulp was completely dissolved, but filter papers and holocellulose were divided into two layers (dissolved and undissolved parts) in the process of centrifugation. The structure of aerogel from dissolved pulp showed porous pores in the surface and net-shaped network in the inner part. Aerogels from filter paper and holocellulose had the condensed porous network surface and the open-pore nano-fibril network inner structure. Undissolved form of fibers was observed in the aqueous solution of aerogel from holocellulose. The BET value ($S_{BET}$) of aerogel from dissolved pulp was ranged in 260~326 $m^2/g$, and it was decreased with the increase of concentration. Whereas, the $S_{BET}$ value of aerogel from filter paper (198~418 $m^2/g$) was increased with the increase of concentration. The $S_{BET}$ value of aerogel from holocellulose were 137 $m^2/g$ at 2% (w/w) of cellulose, and it was increased to maximum 401 $m^2/g$ at 4% (w/w) of cellulose. Then, it was decreased at 5% (w/w) of cellulose.

• Korean Journal of Environmental Agriculture
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• v.19 no.5
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• pp.401-418
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• 2000

1. Production of the artificial zeolite from coal ash Coal fly ash is mainly composed of several oxides including $SiO_2$ and $Al_2O_3$ derived from inorganic compounds remained after burning. As minor components, $Fe_2O_3$ and oxides of Mg, Ca, P, Ti (trace) are also contained in the ash. These components are presented as glass form resulting from fusion in the process of the combustion of coal. In other word, coal ash may refer to a kind of aluminosilicate glass that is known to easily change to zeolite-like materials by hydrothermal reaction. Lots of hot seawater is disposing near thermal power plants after cooling turbine generator periodically. Using seawater in the hydrothermal reaction caused to produce low price artificial zeolite by reduction of sodium hydroxide consumption, heating energy and water cost. As coal ash were reacted hydrothermally, peaks of quartz and mullite in the ash were weakened and disappeared, and new Na-Pl peaks were appeared strengthily. Si-O-Si bonding of the bituminous coal ash was changed to Si-O-Al (and $Fe^{3+}$) bonding by the reaction. Therefore the produced Na-Pl type zeolite had high CEC of 276.7 $cmol^+{\cdot}kg^{-1}$ and well developed molecular sieve structure with low concentration of heavy metals. 2. Utilization of the artificial zeolite in agro-environment The artificial zeolite(1g) could remove 123.5 mg of zinc, 164.7 mg copper, 184.4 mg cadmium and 350.6 mg lead in the synthetic wastewater. The removability is higher 2.8 times in zinc, 3.3 times in copper, 4.7 times in cadmium and 4.8 times in lead than natural zeolite and charcoal powder. When the heavy metals were treated at the ratio of 150 $kg{\cdot}ha^{-1}$ to the rice plant, various growth inhibition were observed; brownish discoloration and death of leaf sheath, growth inhibition in culm length, number of panicles and grains, grain ripening and rice yield. But these growth inhibition was greatly alleviated by the application of artificial zeolite, therefore, rice yield increased $1.1{\sim}3.2$ times according to the metal kind. In addition, the concentration of heavy metals in the brown rice also lowered by $27{\sim}75%$. Artificial Granular Zeolites (AGZ) was developed for the purification of wastewater. Canon exchange capacity was 126.8 $cmol^+{\cdot}kg^{-1}$. AGZ had Na-Pl peaks mainly with some minor $C_3S$ peaks in X-ray diffractogram. In addition, AGZs had various pore structure that may be adhere the suspended solid and offer microbiological niche to decompose organic pollutants. AGZ could remove ammonium, orthophosphate and heavy metals simultaneously. Mixing ratio of artificial zeolite in AGZs was related positively with removal efficiency of $NH_4\;^+$ and negatively with that of $PO_4\;^{3-}$. Root growth of rice seedling was inhibited severely in the mine wastewater because of strong acidity and high concentration of heavy metals. As AGZ(1 kg) stayed in the wastewater(100L) for 4days, water quality turned into safely for agricultural usage and rice seedlings grew normally.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.25-33
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• 2018

Renewable energy has been of interests in the area of modern alternative fuels. Biogas is produced in waste landfill sites through anaerobic digestion processes, including hydrolysis, acidogenesis, organic acid fermentation (acetogenesis), and methane fermentation (methanogenesis). High contents of fine dust and moisture limited its utilization for direct combustion, town gas and vehicle fuel. Thus, this study proposed a new design for a cooling device using a centrifugal cyclone for simultaneous removal of fine dust and moisture as a pretreatment in the purification processes. A heat exchanger and an ID fan, which are installed inside and outside of the cyclone, in order to cool the humid gas below the freezing point and form a foggy mist. Such an atmosphere enhanced to capture fine dust as recirculating the cold mist flow. The water removal rate was 80.8% at a relative humidity of 95%, and the particle removal efficiency was 98.3% for $2.5{\mu}m$. Simultaneous removal efficiency was 70.8% and 99.6% for particle and moisture respectively.

• Cartoon and Animation Studies
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• s.31
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• pp.227-248
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• 2013

With the advancement of computers, opening title sequences in movies are continuously improving. Initially, titles and opening credits were created using what is called the optical method, whereby text was photographed on separate film and then copied onto the movies film negative. In contemporary movie making, however, the title sequence may be seamlessly integrated into the beginning of the movie by an insertion method that not only allows for more diverse technical expression, including the use of both 2D and 3D graphics, but also for its emergence as an independent art form. As such a title sequence, in as little as 50 seconds or up to 10 minutes, is able to convey the films concept while also suggesting more implicit intricacies of plot and thereby eliciting greater interest in the movie. Moreover, according to the directors intent and for a variety of purposes, the title sequence, while maintaining its autonomy, is inseparable from the movie as an organic whole; therefore, it is possible to create works that are highly original in nature. The purpose of this study is to analyze the kinetic typography that appears in title sequences of ten films produced by the Korean entertainment industry in 2012. Production techniques are analyzed in a variety of ways in order to predict the future direction of opening title sequences, as well as present aesthetic and technical models for their creation.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.9
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• pp.641-647
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• 2014

In this study, sludge waste which has a difficulty in treating it was used to manufacture a fiber type of biosorbent. To solve the problems such as the release of organic pollutants and the difficulty in separating solid from treated water, entrapment method using Ca-alginate was used to immobilize sludge waste. Considering ease of manufacture as well as improvement of adsorptive ability, the biosorbent was manufactured in the form of fiber type. Optimum immobilization condition for minimizing the amount of alginate used and maximizing the performance of biosorbent was determined to be 10 g/L alginate concentration, 40 g/L sludge concentration, and 0.3-0.4 mm fiber diameter. The maximum Cd(II) uptake of the biosorbent was 60.73 mg/g. Pseudo-second-order kinetic model and Langmuir isotherm model adequately described the dynamic and equilibrium behaviors of Cd(II) biosorption onto the biosorbent, respectively. In conclusion, sludge waste generated from wastewater treatment process is a cheap raw material for the manufacture of biosorbent which can be used to remove toxic heavy metals from industrial wastewaters efficiently.

• Journal of the Korean Wood Science and Technology
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• v.16 no.2
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• pp.79-89
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• 1988

This experiment was carried out to investigate the difference of compositions between petroleum ether extract and its tall oil in Pinus rigida Mill. xylem and to obtain the basic data on effective extraction and its utilization of by-product, resin and fatty acid, when pulp making. After both petroleum ether extract from wood meal and its tall oil in pitch pine were separated to the resin and fatty acid by using DEAE-Sephadex and aluminum oxide column, these were analyzed with gas chromatograph. The results obtained were as follows: 1. Fatty acids contained as ester form in living trees were varied by peroxide of organic solvent in petroleum ehter extraction and cooking chemicals in cooking. 2. Pimaric-type acid was eluted earlier than abietic-type acid in resin acids and the fewer the carbons, the earlier the elution in fatty acids. 3. The retention time of SE-30 column was even smaller than that of OV-101 column but the relative retention time obtained by using methyl pimarate and methyl stearate as internal standard was nearly identical. 4. Both petroleum ether extract and tall oil mainly consisted of resin acids, expecially abietic-type acid. 5. Tall oil had more fatty acid but less resin acid than petroleum ether extract. Also, the content of unidentified materials was increased owing to the isomerization and the shift of double bond position in unsaturated fatty acids by high temperature and cooking chemicals when cooking.

• Food Science and Preservation
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• v.19 no.1
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• pp.159-166
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• 2012

To investigate the characteristics of $Gammakgeolli$ to which processed forms of persimmon were added, $Gokkam$, $Gammalaengi$, whole powder, peel powder, and paste were used as various processed forms. The moisture, total polyphenol, and soluble-solid contents of the persimmon used for making $Gammakgeolli$ showed a big difference according to the processed form of persimmon, and influenced the total polyphenol and alcohol contents of the $Gammakgeolli$. The pH and total acid of the $Gammakgeolli$, which were 3.7~4.1 and 0.20~0.29% (w/v), respectively, were similar to those of commercial $Makgeolli$. The amino acidity increased on the fifth day after fermentation from that on the third day, and showed relatively high levels in the whole power, peel power, and paste. The volatile-acid contents of the $Gammakgeolli$s were within the range of 80~100 ppm and showed the highest level in the persimmon-paste-treated sample. Among the major organic acids of $Gammakgeolli$ (oxalic, citric, tartaric, malic, succinic, lactic, and acetic acid), lactic acid had the highest concentration. The $Gammakgeolli$ to which hole power or paste was added showed a high level of yellowness and a good color in the sensatory evaluation. In the sensory evaluation (selection rate) of the taste and overall acceptability, the $Gammakgeolli$ treated with $Gammalaengi$ was the best.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1261-1262
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• 2008

Laser-based crystallization techniques are ideally-suited for forming high-quality crystalline Si films on active-matrix display backplanes, because the highly-localized energy deposition allows for transformation of the as-deposited a-Si without damaging high-temperature-intolerant glass and plastic substrates. However, certain significant and non-trivial attributes must be satisfied for a particular method and implementation to be considered manufacturing-worthy. The crystallization process step must yield a Si microstructure that permits fabrication of thin-film transistors with sufficient uniformity and performance for the intended application and, the realization and implementation of the method must meet specific requirements of viability, robustness and economy in order to be accepted in mass production environments. In recent years, Low Temperature Polycrystalline Silicon (LTPS) has demonstrated its advantages through successful implementation in the application spaces that include highly-integrated active-matrix liquid-crystal displays (AMLCDs), cost competitive AMLCDs, and most recently, active-matrix organic light-emitting diode displays (AMOLEDs). In the mobile display market segment, LTPS continues to gain market share, as consumers demand mobile devices with higher display performance, longer battery life and reduced form factor. LTPS-based mobile displays have clearly demonstrated significant advantages in this regard. While the benefits of LTPS for mobile phones are well recognized, other mobile electronic applications such as portable multimedia players, tablet computers, ultra-mobile personal computers and notebook computers also stand to benefit from the performance and potential cost advantages offered by LTPS. Recently, significant efforts have been made to enable robust and cost-effective LTPS backplane manufacturing for AMOLED displays. The majority of the technical focus has been placed on ensuring the formation of extremely uniform poly-Si films. Although current commercially available AMOLED displays are aimed primarily at mobile applications, it is expected that continued development of the technology will soon lead to larger display sizes. Since LTPS backplanes are essentially required for AMOLED displays, LTPS manufacturing technology must be ready to scale the high degree of uniformity beyond the small and medium displays sizes. It is imperative for the manufacturers of LTPS crystallization equipment to ensure that the widespread adoption of the technology is not hindered by limitations of performance, uniformity or display size. In our presentation, we plan to present the state of the art in light sources and beam delivery systems used in high-volume manufacturing laser crystallization equipment. We will show that excimer-laser-based crystallization technologies are currently meeting the stringent requirements of AMOLED display fabrication, and are well positioned to meet the future demands for manufacturing these displays as well.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.227-238
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• 2016

This review article highlights different types of nano-sized catalysts for the selective alcohol oxidation to form aldehydes (or ketones) with supported or immobilized metal nanoparticles. Metal nanoparticle catalysts are obtained through dispersing metal nanoparticles over a solid support with a large surface area. The nanocatalysts have wide technological applications to industrial and academic fields such as organic synthesis, fuel cells, biodiesel production, oil cracking, energy conversion and storage, medicine, water treatment, solid rocket propellants, chemicals and dyes. One of main reactions for the nanocatalyst is an aerobic oxidation of alcohols to produce important intermediates for various applications. The oxidation of alcohols by supported nanocatalysts including gold, palladium, ruthenium, and vanadium is very economical, green and environmentally benign reaction leading to decrease byproducts and reduce the cost of reagents as opposed to stoichiometric reactions. In addition, the room temperature alcohol oxidation using nanocatalysts is introduced.