• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.2028-2030
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• 2012

The single-crystal structure of $CaCl_2{\cdot}2C_6H_{12}O_6{\cdot}3H_2O$ was determined with Mr=525.34, a=16.054(7) ${\AA}$, b=7.864(4) ${\AA}$, c=10.909(5) ${\AA}$, ${\beta}=127.894(8)^{\circ}$, V=1086.9(9) ${\AA}^3$, C2, Z=2 and $R$=0.0227 for 1727 observed reflections. The fructose moiety of the complex exists as a ${\beta}$-D-pyranose. The calcium ion is surrounded by eight oxygen atoms, These are arranged in symmetry-related pairs derived from four sugar and two water molecules. Three nonvicinal hydroxyl groups of fructose are involved in calcium binding. All the hydroxyl groups and water molecules are involved in forming an extensive hydrogen-bond network.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.4
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• pp.144-148
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• 2005

In this study, the microwave dielectric properties of $0-6TiTe_3O_8-0.4MgTiO_3$ ceramic with $H_3BO_3$ and SnO were investigated to reduce the sintering time for the LTCC application. According to the X-ray diffraction patterns, both of $0-6TiTe_3O_8-0.4MgTiO_3$ ceramic with $H_3BO_3$ and SnO had the columbite structure of $TiTe_3O_8$ Phase, the ilmenite structure of $MgTiO_3$ phase. The density and dielectric constant of the $0-6TiTe_3O_8-0.4MgTiO_3$ ceramics with $H_3BO_3$ sintered at $830^{\circ}C$ for 1 hour were decreased but the quality factor was not changed with addition of $H_3BO_3$. Also the temperature coefficient of resonant frequency was not changed hardly. In the case of addition of SnO, the density and dielectric constant were increased but the quality factor was decreased and the temperature coefficient of resonant frequency was shifted to the negative(-) direction.

• Archives of Pharmacal Research
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• v.21 no.2
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• pp.106-112
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• 1998

Structure-activity relationship of 20 fluoroquinolones was studied using the susceptible and 4 resistant Escherichia coli which were developed against 4 fluoroquinolones [ciprofloxacin (1), KR-10755 (6), norfloxacin (2), and ofloxacin (3)] in our laboratory. The C-7 and C-8 substituents of fluoroquinolone were important in various functions such as the inhibitory activity on DNA gyrase, permeability, and efflux. Among 20 fluoroquinolones, compounds with a 3-methyl-3,7-diazabicyclo[3.3.0]octan-1(5)-ene-7-yl substituent at the C-7 position or a chlorine substituent at the C-8 position showed a good inhibitory activity on DNA gyrase (especially a mutated DNA gyrase). Compounds with a 3,7-diazabicyclo [3.3.0]octan-1(5)-ene-7-yl substituent at the C-7 position showed good permeability in the susceptible and resistant strains, while compounds with a fluorine substituent at the C-8 position were less eff luxed from cells.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.9-14
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• 1977

The productive structure and the productivity of ${\times}$Populus albaglandulosa plantations, where are middle parts of the Korean peninsula, were studied by means of stratifying clip technique and of allometry. The densities of stands in the sample areas were 693 trees/ha in 6 year-old plantation and 527 or 625 trees/ha in 9 year-old one. The photosynthetic part of the productive structure was not shown normal conical form but layering. So this was efficient to transmit solar radiation into the stand floor. The standing crop of the terrestrial parts of 6 year-old plantation was 18.11 ton/ha and that of 9 year-old one 38.8 to 47.3 ton/ha. The wood volume to trunk to 6 year-old was $31.3m^3/ha$ and that of 9 year-old was 68.8 to $83.9m^3/ha$. The annual net production of 6 year-old plantation was 4.8 ton/ha/year and that of 9 year-old one was 10.0 to 11.7 ton/ha/year and its wood volume of trunks was 17.9 to $21.1m^3/ha/year$. In the 9 year-old plantation the standing crop or the annual net production was different between two sample areas. This seemed that the cause was not due to chemical character but to physical character of soil.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.3 no.1
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• pp.24-30
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• 2010

In this paper, a novel electrically small monopole type resonant antenna is proposed. The very short length monopole (${\iota}{\approx}{\lambda}_g/15$ ) acts as a capacitive element and the slot on the ground structure acts as an inductive element, hence the combined system with these two elements thus form an LC resonator. The equivalent circuit model of the antenna structure was used to analysis and qualify the design correctness. Although the proposed antenna has very small size, it shows good performances. The measured maximum gain and radiation efficiency of the fabricated antenna at the frequency of 2.1 GHz was 3.6 dBi and 77.8 %, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.7
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• pp.712-720
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• 2003

In this paper, a multi-layered metallic disk array structure(MDAS) excited by cross-dipole elements was proposed for efficiently shaping of flat-topped element patterns(FTEP) with circular polarization. The MDAS excited by cross-dipole elements has advantages to decrease in volume and weight of an overall array antenna and so, it is appropriate for the FTEP applications of a ralativlely low frequency band. In order to verify the effectness of this structure, the MDAS breadboard operated at X-band(7.9 ∼ 8.4 GHz) was fabricated, and its design parameters were experimentally optimized on the basis of the previous design experience. The experimental results were shown that the MDAS could shape good FTEPs of ${\pm}$20$^{\circ}$beam width at least within a 6.1 % frequency band.

• Korean Journal of Crystallography
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• v.13 no.3_4
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• pp.148-151
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• 2002

The molecular and crystal structure of metalaxyl C/sub15/H/sub21/NO₄, was determined by single crystal x-ray diffraction study. Crystallographic data for, title compound P2₁/c, a=7.849(4) Å, b=13.081(5) Å, c=15.100(3) Å, β=101.8(2)°, V= 1517.6(3) ų, Z=4. The molecular. Structure model was solved by direct method and refined by full-matrix least- squares. The final reliable factor, R, is 0.067 for 1694 independent reflections (F/sub o//sup 2/>4σ(F/sub o//sup 2/)). The molecular structure of title compound shows an intramolecular hydrogen bond: Cl2-Hl2A…O1.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1213-1221
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• 2002

Friedel-Crafts alkylation reaction of an isomeric mixture of 1,2,3,4,5,6,7,8- (2) and 1,2,3,4,5,6,7,8-octahydrophenanthrene (2') with excess vinylchlorosilanes such as vinyl(methyl)dichlorosilane (1a) and vinyltrichlorosilane (1b) in the presence of aluminum chloride catalyst at 80 $^{\circ}C$ gives only one dialkylated products, 9,10-bis[2-(chlorosilyl)ethyl]-1,2,3,4,5,6,7,8-octahydroanthrenes [(Cl2XSiCH2CH2)2C14H16: X = Me (4a), Cl (4b)] in good yields, but 9,10-bis[2-(chlorosilyl)ethyl]-1,2,3,4,5,6,7,8-octahydrophenanthrenes are not obtained. However, monoalkylation of 2 with 1 affords a mixture of both isomeric compounds, 9-[2-(chlorosilyl)ethyl]-1,2,3,4,5,6,7,8-octahydroanthracenes 3 and -phenanthrenes 3'. The yield of product 3' is always higher than that of 3. When a mixture of 3 and 3' is alkylated again with 1, only product 4 without phenanthrene type compounds is obtained, indicating that the isomerizations between 2 and 2', or 3 and 3'occur under the alkylation condition. The alkylation with dimethylvinylchlorosilane or trimethylvinylsilane did not proceed. The structure of 4a is determined by X-ray single crystal diffraction analysis.

• Journal of Life Science
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• v.14 no.6 s.67
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• pp.1009-1017
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• 2004

Sialyltransferases cloned so far show the remarkable tissue-specific expression, which is correlated with the existence of cell type-specific sialylated sugar structure in glycoconjugates. In the previous studies, we found various mRNA isoforms of human sialyltransferases generated by alternative splicing and alternative promoter utilization. To understand the regulatory mechanisms for specific expression of human sialyltransferase genes and for production of their mRNA isoforms, in this study, we have isolated and characterized five kinds of human sialyltransferase genes: hST3Gal II, hST8Sia II, hST8Sia III, hST8Sia IV, and hST8Sia V. The hST3Gal II gene is composed of six exons, which span over 17kb, with exons ranging in size from 46 to over 1017 bp. The hST8Sia III gene comprises over 10 kb, and consists of only four exons, which is much smaller and simpler than other human sialyltransferase genes. In contrast, three genes (hST8Sia II, hST8Sia IV and hST8Sia V) span more than 70 kb, and comprise five or more exons. All exon-intron boundaries follow the GT-AG rule. In particular, the sialylmotif L, which is a highly conserved region in all cloned sialyltransferases, was found in one exon of hST8Sia III, whereas this motif is encoded by discrete exons in the other human sialyltransferases. Exon structures of these sialyltransferase genes show the structural diversity, as found in other human sialyltransferase genes reported so far. We determined the transcription start site of hST3Gal II gene by the 5'-RACE and cap site hunting experiments.

• Culinary science and hospitality research
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• v.11 no.3 s.26
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• pp.151-165
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• 2005

The current study aims to help field managers of companies providing foodservice for institutions to establish the more appropriate cost management strategy by analyzing the cost structure of foodservice center in institutions by operating types and the number of people served. From the result analyzing 161 foodservice centers, the number of factories was highest with 39.8% while offices 26.7%, schools 20.5%, and hospitals 13%. In terms of the number of people served, below 500 persons was 27.6%, 501${\sim}$l,000 persons was 23.9%, 1,001${\sim}$2,000 persons was 22.7%, and over 2,001 persons was 25%. In the demographic characteristics of managers, women occupied over 92%. The reason for this is usually dieticians perform management duties. For the age of workers, 70.8% were older than 40s, which ran become the cause of a rise in cost by causing the decrease of productivity by aging. Therefore, appropriate countermeasures are required. In case of workers in production, women occupy 962 persons (82.2%) rating absolute majority like mangers. This is because cooks are in charge of almost every producing activity of meal facilities. In addition, more than 72.9% of workers in production were over 40 years old, which requires diversified studies to promote efficiency of production associated with the aging problem. In proportion of sales compared with cost material cost presented the highest percentage with 54.5% while labor cost 28.3%, general expenses 9.6% and business profit 7.6%.