• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.283-288
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• 2004

In case while modulation index (M) is more than 0.7, the spectrum of motor voltage and current of a conventional two-phase SRP scheme are not reduced considerably. To solve the problems of a conventional two-phase SRP, this paper proposes a two-phase SRP(DZSRP) with double zero vector mode which zero vector is selected as V(111) in case of $M\;\geqq\;0.7$, and zero vector is selected as V(000) if M < 0.7. For the validity of the proposed method, a 16 bit micro-controller C167 was used and the experiments were conducted with the 1.5kw induction motor under load condition. And the experimental results show that the switching noise spectrum for all the M are spread to a wide band area.

• International Commerce and Information Review
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• v.10 no.2
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• pp.283-304
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• 2008

According to globalization and localization of world economics international trade payment method was also changed. A traditional payment was Letter of Credit basis, however it is being increased to various methods such as remittance, documentary collection(D/P, D/A) and open account. In order to acquire a secure export payment, exporters prefer to L/C basis which is guaranteed by a reliable bank. However, the L/C should bear a security so that importers would rather documentary collection than L/C. The reasons for the preference of collection payment rather than L/C are a low commission cost, the conversion of buyer's market from seller's market due to severe competition in the world market, transaction increase between main office and branches and a right to control the goods until executing the payment by exporters. Besides of them, collection payment can handle safer and faster than open account basis. However, the collection payment has a risk which it isn't guaranteed by bank for the payment so that I would suggest countermeasures to minimize the payment risk utilizing the collection basis as follows; using export credit insurance system, a large domestic credit report provider such as D&B for absolutely fresh and new information, a collection proxy service for overseas deferred credit and suggestion specifying to order B/L not straight one on consignee in order to transfer the right of ownership with endorsement without problem.

• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.283-291
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• 2014

Talc ($Mg_3Si_4O_{10}(OH)_2$), one of sheet silicates, is soft and has been widely used in industry. Powdered talc specimen was synthesized at the pressure of 200 MPa and temperature of $600^{\circ}C$ using external heated hydrothermal high pressure apparatus. High pressure angular dispersive X-ray diffraction (ADXRD) mode experiments were performed at the Pohang Light Source (PLS) using the symmetrical diamond anvil cell (SDAC). Compression pressure was loaded up to 11.06 GPa at room temperature. This synthetic talc shows no phase transition(s) within the present pressure limit. Based on ADXRD data, bulk modulus of talc was calculated to be 72.4 GPa using Birch-Muranghan equation of state (EOS). This value is lower than that of natural talc determined previously.

• Preventive Nutrition and Food Science
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• v.9 no.3
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• pp.283-288
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• 2004

Superoxide dismutase (SOD) from tomato (Lycopersicon esculentum Mill.) fruit was purified by ammonium sulphate precipitation, Sephadex G-100 and DEAE-cellulose column chromatographies. A 22 fold purification and an overall yield of 44% were achieved. The purified enzyme was a homodimer with Mr 37.1 kDa and subunit Mr 18.2 kDa as judged by SDS-PAGE. SOD showed $K_{m}$ values of 25 ${\times}$ 10$^{-6}$ M and 1.7 ${\times}$ 10$^{-6}$ M for nitroblue tetrazolium (NBT) and riboflavin as substrates, respectively. The enzyme was thermostable upto 5$0^{\circ}C$ and exhibited pH optima of 7.8. The effect of metal ions and some other compounds on enzyme activity was studied. $Co^{2+}$ and $Mg^{2+}$ were found to enhance relative enzyme activities by 27 % and 73 %, respectively, while M $n^{2+}$ inhibited the SOD activity by 64%. However, $Ca^{2+}$ and C $u^{2+}$ had no effect on enzyme activity. Other compounds like $H_2O$$_2$ and Na $N_3$ inhibited enzymatic activities by 60% and 32%, respectively, while sodium dodecyl sulphate (SDS), chloroform plus ethanol and $\beta$-mercaptoethanol had no effect on the activity of SOD. of SOD.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.278-283
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• 2013

A gram-positive, rod-shaped, spore-forming, motile thermophilic bacterium was isolated from a sterilization oven. The microorganism GWE1, formally named Geobacillus wiegelii identified as a member of the genus Geobacillus. GWE1 grew under aerobic conditions of between $60-80^{\circ}C$ (optimum $670^{\circ}C$), in a pH range of 3.0-8.0 (optimum $pH^{70^{\circ}C}$ 5.8), and between 0 and 2 M NaCl (optimum 0.3 M). The membrane polar lipids were dominated by branched saturated fatty acids, which included as the major constituents; iso-15:0 (13.3%), 16:1(${\omega}7$) (12.8%), 16:0 (28.5%), iso-17:0 (13.5%) and anteiso-17:0 (12.3%). The DNA G+C content was 47.2 mol% (determined by HPLC). The 16S rRNA gene sequence of GWE1 showed a high similarity with Geobacillus caldoxylosilyticus (97%). However, the level of DNA-DNA relatedness was only 58%. These data suggest that GWE1 is probably a novel specie of the genus Geobacillus.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.55-55
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• 2022

Corylopsis Siebold & Zucc. (Hamamelidaceae) is widely used for horticultural plant and comprise ca. 25 species in East Asia (1 species in Korea; 4 species in Japan; 20 species in China). Previous revisions have gone from 7 to more than 30 species, causing confusion in the nursery industry and public gardens. Due to morphological similarity within Corylopsis, molecular research is needed to distinguish it. In this study, the chloroplast genome of C. gotoana and C. pauciflora distributed in Japan was completed by using NGS (Next-Generation Sequencing) technique. The genome size of C. gotoana and C. pauciflora were 159,434 bp (large single-copy (LSC): 88,164 bp; small single-copy (SSC): 18,702 bp; inverted repeat regions (IRs): 26,284 bp) and 159,363 bp (LSC: 88,097 bp; SSC: 18,700 bp; IRs: 26,283 bp), respectively. In addition, we investigated the repeats, SNPs, and indels, and that could be used as DNA markers. Phylogenetic analysis demonstrated that C. pauciflora was sister to C. gotoana and C. spicata. The genus Corylopsis is a monophyletic group and Loropetalum is closely related to Corylopsis. The results of our study will provide the basic data necessary for the analysis of the species identification markers and genetic diversity within the genus Corylopsis in the future.

• Journal of the Korean Society for Heat Treatment
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• v.17 no.5
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• pp.283-292
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• 2004

The effects of the annealing parameters on microstructures were examined in a cold-rolled high strength steel containing 0.1% C, 0.5% Si, 1.5% Mn, and 0.04% Nb. It was impossible to avoid martensite in the microstructure even though the continuous annealing parameters were controlled. This indicates that the alloying elements such as silicon and manganese contributing to manganese equivalent($Mn_{eq}$) should be reduced to produce the ferrite-pearlite microstructure for the solid solution and precipitation hardened steel. It was found that a decrease in the rapid cooling temperature to $520^{\circ}C$ was effective to change the microstructure from ferrite-martensite to ferrite-pearlite-martensite. Typical dual-phase properties exhibiting a low yield ratio and a continuous yielding behavior were obtained when the rapid cooling temperature was in the range of $680^{\circ}C$ to $600^{\circ}C$. The critical volume fraction of martensite for the typical properties of dual-phase steel was about 11 percent.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.283-287
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• 1997

In order to identify the structural requirement at 4-position of 1-arylsulfonyl-4-phenyl-4,5-dihydro-2-limidazolones 3 for their cytotoxicity, the corresponding 1-arylsulfonyl-4-cyclohexyl-4,5-dihydro-2-imidazolones 4 were synthesized and their in vitro cytotoxicity against human solid tumor cell lines were measured. Unlike compounds 3a-c, cyclohexyl analogues 4a-c do not show the cytotoxicity. This dramatic loss of activity of these analogues on the volume change with the bulkier cyclohexyl group indicates that the planar structure at 4-position of 1-arylsulfonyl-4-pheny-4,5-dihydro-2-limidazolones 3 is required for their activity as an important pharmacophoric moiety.

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.283-289
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• 1998

To determine the differences among cultivated , non-cultivated and imported bupleurum falcatum, contents and compositions of fatty acids and saikosaponins which are known as a major biologically acitive compounds in Bupleurum falcatum were meausred with GC and HPLC. Color of grinded powder of Bupleuri radix determined by colorimeter showed that the imported one has the highest white and yellow coloer Among the Bupleuri radix cultivated in China, Hong-siho(red-Bupleurum) produced in Yungil Province contained the highest red color. Cultivated Korean Bupleurum radix contained higher saikosaponi a, c, and than the imported ones which were cultivated in Yungil, Ankuk , and Gillium Province in China. Levels of saikosaponin c are 3 times higher in cultivated Korean Bupleuria radix compared the with imported ones. Furthermore, Bupleurum falcatum cultivated in Korea contained higher amount of palmitic and linoleic acids than those of improted and non-cultivated ones. Particularly they contain two to six times higher linoleic acid.

• Nutrition Research and Practice
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• v.2 no.4
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• pp.283-288
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• 2008

This study was carried out to determine whether a short-tenn zinc supplementation contributes to beneficial changes in glycemic control among type 2 diabetic patients. Seventy-six diabetic subjects and 72 normal adults participated in this study. Subjects were divided into supplemented and control groups. Forty-four diabetic patients and 34 normal subjects were supplemented with 50 mg zinc daily as zinc gluconate for 4 weeks. Zinc status was assessed from fasting plasma levels and urinary excretion. The effects of zinc supplementation on fasting blood glucose, $HbA_{1c}$, insulin, and C-peptide were measured at the beginning of the study and after 4 weeks of supplementation. The changes in glycemic control indicators were compared between diabetic groups, classified by baseline $HbA_{1c}$ levels, and by diabetic duration. At baseline, the incidence of marginal zinc deficiency in the diabetic group, as determined by plasma zinc level, was approximately twice as high as in the normal adult group. The changes of $HbA_{1c}$ concentration, and fasting blood glucose following supplementation were not statistically significant in diabetic subjects. In normal subjects, a significant decrease of $HbA_{1c}$ occurred only in the zinc supplemented group. No significant changes were observed for serum insulin and C-peptide in diabetic as well as normal subjects. However, when the changes were compared by baseline $HbA_{1c}$ level, we found that diabetic subjects with $HbA_{1c}\;{\geq}\;7.5%$ showed significantly improved levels of $HbA_{1c}$ and fasting glucose after Zn supplementation. While such improvement in fasting blood glucose was significant among diabetics with shorter diabetic duration, significant levels of increase in serum insulin and C-peptide were observed in zinc supplemented subjects with longer diabetic duration. Fasting blood glucose was significantly decreased, whereas serum insulin and C-peptide were increased in diabetics with marginal zinc status. Therefore, we suggest that Zn supplementation for a short-term period may improve glycemic control in diabetic patients with higher $HbA_{1c}$ levels and marginal zinc status.