• Asian Journal of Atmospheric Environment
• /
• v.2 no.1
• /
• pp.34-46
• /
• 2008

Emissions inputs for use in air quality modeling of Korea were generated with the emissions inventory data from the National Institute of Environmental Research (NIER), maintained under the Clean Air Policy Support System (CAPSS) database. Source Classification Codes (SCC) in the Korea emissions inventory were adapted to use with the U.S. EPA's Sparse Matrix Operator Kernel Emissions (SMOKE) by finding the best-matching SMOKE default SCCs for the chemical speciation and temporal allocation. A set of 19 surrogate spatial allocation factors for South Korea were developed utilizing the Multi-scale Integrated Modeling System (MIMS) Spatial Allocator and Korean GIS databases. The mobile and area source emissions data, after temporal allocation, show typical sinusoidal diurnal variations with high peaks during daytime, while point source emissions show weak diurnal variations. The model-ready emissions are speciated for the carbon bond version 4 (CB-4) chemical mechanism. Volatile organic carbon (VOC) emissions from painting related industries in area source category significantly contribute to TOL (Toluene) and XYL (Xylene) emissions. ETH (Ethylene) emissions are largely contributed from point industrial incineration facilities and various mobile sources. On the other hand, a large portion of OLE (Olefin) emissions are speciated from mobile sources in addition to those contributed by the polypropylene industry in point source. It was found that FORM (Formaldehyde) is mostly emitted from petroleum industry and heavy duty diesel vehicles. Chemical speciation of PM2.5 emissions shows that PEC (primary fine elemental carbon) and POA (primary fine organic aerosol) are the most abundant species from diesel and gasoline vehicles. To reduce uncertainties in processing the Korea emission inventory due to the mapping of Korean SCCs to those of U.S., it would be practical to develop and use domestic source profiles for the top 10 SCCs for area and point sources and top 5 SCCs for on-road mobile sources when VOC emissions from the sources are more than 90% of the total.

• Advances in materials Research
• /
• v.13 no.3
• /
• pp.211-220
• /
• 2024

Polylactic acid or polylactide (PLA) is a biodegradable thermoplastic that can be produced from renewable material to create various components for industrial purposes. In 3D printing technology, PLA is used due to its good mechanical, electrical, printing properties, environmentally friendly and non-toxic properties. However, the physical properties and excellent electrical insulation properties of PLA have limited its application. In this study, with the carbon black (CB) as filler added into PLA, the lattice spacing and morphology were investigated by using X-ray diffraction (XRD) and scanning electron microscope (SEM), respectively. The physical properties of PLA-carbon composite were evaluated by using tensile test, shore D hardness test and density and voids measurement. Impedance test was conducted to investigate the electrical properties of PLA-Carbon composites. The results demonstrate that the inclusion of carbon black as filler enhances the physical properties of the PLA-carbon composites, including tensile properties, hardness, and density. The addition of carbon black also leads to improved electrical conductivity of the composites. Better enhancement toward the electrical properties of PLA-carbon composites is observed with 1wt% of carbon black in N774 grade. The N550 grade with 2wt% of carbon black shows better improvement in the physical properties of PLA-carbon composites, achieving 10.686 MPa in tensile testing, 43.330 in shore D hardness test, and a density of 1.200 g/cm3 in density measurement. The findings suggest that PLA-carbon composites have the potential for enhanced performance in various industrial applications, particularly in sectors requiring improved physical and electrical properties.

• KEPCO Journal on Electric Power and Energy
• /
• v.8 no.1
• /
• pp.15-19
• /
• 2022

The radial distribution systems (RDS) commonly used around the world has the following disadvantages. First, when the DL is operated on a radial system, the line utilization rate is usually kept low. Second, if a fault occurs in the radial DL, a power outage of 3 to 5 minutes is occurring depending on the operator's proficiency and fault situation until the fault section is separated and the normal section is replaced. To solve this problem, Various methods have been proposed at domestic and foreign to solve this problem, and in Korea, research is underway on the advanced system of operating multiple linked DL always. A system that is electrically linked always, and that is built to enable high-speed communication during the protection coordination is named networked distribution system (NDS). Because the load shares the DL, the line utilization rate can be improved, and even if the line faults, the normal section does not need to be cut off, so the normal section does not experience a power outage. However, since it is impossible to predict in which direction the fault current will flow when a failure occurs in the NDS, a communication-based protection coordination is used, but there is no backup protection coordination method in case of communication failure. Therefore, in this paper, we propose a protective cooperation method to apply as a backup method when communication fails in NDS. The new method is to change TCC by location of CB using voltage drop in case of fault.

• Korean Journal of Breeding Science
• /
• v.41 no.3
• /
• pp.220-227
• /
• 2009

This study was conducted to select superior families based on the open-pollinated (OP) progeny tests of P. densiflora. A total of 232 OP families were analyzed for relative height growth. The OP progeny test trials were established at 1 to 4 sites from 1975 to 1987. To minimize temporal and spatial variation, we applied the standardization method for family selection. In each progeny test, superior and inferior families were selected at ages of 10, 20 and 30. Relative height growth rate (RHGR), growth speed at a given time unit, was comparatively high at age of 10 with range from 0.1 to 0.6 and showed a large variation among families. However, after age 15, the RHGR was low (average 0.04) and also the variation was not significantly different among families. To reduce selection errors due to age differences (from age 23 to 35) of tests, we made the family selection after age 15 when the values of RHGR were stable. Height growth at each age was transformed to be height growth at age 35 based on the RHGR. As the results, family CB2, CB3, KW99 and KW2 were selected as superior families and KW158, KW22, KB40 and GG1 were considered as inferior ones, respectively. Rank correlations (r) between test ages and selection age 35 were high and statistically significant; r = 0.881 between age 30 and 35, 0.653 between age 20 and 35, and -0.222 between age 10 and 35.

• Journal of Microbiology and Biotechnology
• /
• v.21 no.3
• /
• pp.267-273
• /
• 2011

Methyl violet, used extensively in the commercial textile industry and as a biological stain, is a hazardous recalcitrant. Aspergillus sp. strain CB-TKL-1 isolated from a water sample from Tsumoriri Lake, Karzok, Ladakh, India, was found to completely decolorize methyl violet within 24 h when cultured under aerobic conditions at $25^{\circ}C$. The rate of decolorization was determined by monitoring the decrease in the absorbance maxima of the dye by UV-visible spectroscopy. The decolorization of methyl violet was optimal at pH 5.5 and $30^{\circ}C$ when agitated at 200 rpm. Addition of glucose or arabinose (2%) as a carbon source and sodium nitrate or soyapeptone (0.2%) as a nitrogen source enhanced the decolorization ability of the culture. Furthermore, the culture exhibited a maximum decolorization rate of methyl violet after 24 h when the C:N ratio was 10. Nine N-demethylated decolorized products of methyl violet were identified based on UV-visible spectroscopy, Fourier transform infrared (FTIR), and LC-MS analyses. The decolorization of methyl violet at the end of 24 h generated mono-, di-, tri-, tetra-, penta-, and hexa-N-demethylated intermediates of pararosaniline. The variation of the relative absorption peaks in the decolorized sample indicated a linear decrease of hexa-N-demethylated compounds to non-N-demethylated pararosaniline, indicating a stepwise N-demethylation in the decolorization process.

• Journal of Microbiology and Biotechnology
• /
• v.22 no.5
• /
• pp.637-641
• /
• 2012

TPDex, a putative dextranase from Thermoanaerobacter pseudethanolicus, was purified as a single 70 kDa band of 7.37 U/mg. Its optimum pH was 5.2 and the enzyme was stable between pH 3.1 and 8.5 at $70^{\circ}C$. A half-life comparison showed that TPDex was stable for 7.4 h at $70^{\circ}C$, whereas Chaetominum dextranase (CEDex), currently used as a dextranase for sugar milling, was stable at $55^{\circ}C$. TPDex showed broad dextranase activity regardless of dextran types, including dextran T2000, 742CB dextran, and alternan. TPDex showed the highest thermostability among the characterized dextranases, and may be a suitable enzyme for use in sugar manufacture without decreased temperature.

• Food Science of Animal Resources
• /
• v.40 no.5
• /
• pp.772-784
• /
• 2020

This study was performed to investigate the effects of taste-related compounds and antioxidatve profiles of retorted samgyetang made from fresh and dried Cordyceps militaris (C. militaris) mushrooms. A total of 48 carcasses were prepared from commercial broilers (CB; Ross, 4 weeks old) and randomly distributed into eight different treatments. Each treatment group consisted of 6 chicken carcasses made with the addition of broth in different condition and concentration of C. militaris mushrooms. The addition concentration was based on the broth volume (v/w) under either fresh or dried conditions ranging from 0% as a control to 1%, 2%, and 3% of C. militaris mushrooms. C. militaris mushrooms contributed to an improvement of meat tenderness and the antioxidative profile that led to a greater suppression of lipid oxidation. The addition of C. militaris mushrooms at 2% could also enrich the flavor and taste-related compounds, particularly the increase in 5'-AMP and umami-related free amino acid compounds, L-aspartic acid and L-glutamic acid. Different addition forms of C. militaris mushrooms, particularly fresh or dried mushrooms, had only small effects on bioactive compounds, where the dried addition could possibly enrich samgyetang broth with higher cordycepin and adenosine contents than the fresh addition. Besides, the addition of C. militaris mushrooms in the dried form could also contribute to a higher antioxidative profile. Eventually, the addition of C. militaris mushrooms with a minimum addition of 2% contributed to an improvement of meat quality, antioxidative profile and flavor improvement of samgyetang.

• Journal of Microbiology and Biotechnology
• /
• v.29 no.3
• /
• pp.382-391
• /
• 2019

Many poultry eggs are discarded worldwide because of infection (i.e., avian flu) or presence of high levels of pesticides. The possibility of adopting egg yolk as a source material to produce polyhydroxyalkanoate (PHA) biopolymer was examined in this study. Cupriavidus necator Re2133/pCB81 was used for the production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) or poly(3HHx), a polymer that would normally require long-chain fatty acids as carbon feedstocks for the incorporation of 3HHx monomers. The optimal medium contained 5% egg yolk oil and ammonium nitrate as a nitrogen source, with a carbon/nitrogen (C/N) ratio of 20. Time course monitoring using the optimized medium was conducted for 5 days. Biomass production was 13.1 g/l, with 43.7% co-polymer content. Comparison with other studies using plant oils and the current study using egg yolk oil revealed similar polymer yields. Thus, discarded egg yolks could be a potential source of PHA.

• The Korean Journal of Nuclear Medicine
• /
• v.12 no.2
• /
• pp.7-16
• /
• 1978

To elucidate the depaminergic control of T.S.H. secretion, we analized the pattern of T.S.H. secretion in seven normal controls and nine primary hypothyroid subjects, before and after single or combined administration of specific dopaminergic,receptor blocker, metoclopramide, and specific depaminergic receptor stimulant, bromergocryptine(CB-154). The results obtained were as follows: 1) There was a significant rise in T.S.H. levels after intra venous injection of metocloramide (10mg) in hypothyroid subjects. But there was no significant rise in T.S.H. levels in normal controls. The T.S.H. response to metoclopramide varied considerably, being large in mild cases and small in severely hypothyroid subjects. 2) There was a significant fall in T.S.H. levels after oral administration of bromergocryptine (2mg) in hypothyroid subjects, but there was no significant fall in T.S.H. levels in normal controls. 3) There was no significant fluctuation in T.S.H. levels after combined administration of both metoclopramide and bromergocrytine. 4) There was no significant fluctuation in T.S.H. levels after intravenous injection of normal saline(2ml) in both hypothyroid and normal subjects. 5) There was no significant change in serum $T_3\;and\;T_4$ after administration of metoclopramide and and bromergocryptine respectively and serially. These data support the fact that there is a dopaminergic control in the secretion of T.S.H. in the human.

• Journal of Intelligence and Information Systems
• /
• v.12 no.2
• /
• pp.1-15
• /
• 2006

Currently the mobile web service is growing with a tremendous speed and mobile contents are spreading extensively. However, it is hard to search what the user wants because of some limitations of cellular phones. And the music is the most popular content, but many users experience frustrations to search their desired music. To solve these problems, this research proposes a hybrid recommendation system, MOBICORS-music (MOBIle COntents Recommender System for Music). Basically it follows the procedure of Collaborative Filtering (CF) system, but it uses Contents-Based (CB) data representation for neighborhood formation and recommendation of new music. Based on this data representation, MOBICORS-music solves the new item ramp-up problem and results better performance than existing CF systems. The procedure of MOBICORS-music is explained step by step with an illustrative example.