• YAKHAK HOEJI
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• v.43 no.1
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• pp.5-10
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• 1999

As one of the serial studies on the specific and indigenous plants of Mt. Chiri the constituents of aerial part from filipendula formosa (Rosaceae) were investigated. From of the MeOH extract, five flavonol glycosides, kaempferol-3-O-$\beta$-D-galactopyranoside, querecetin-3-O-$\beta$-D-galactopyranoside, quercetin-3-O-$\alpha$-Lrhamopyranosyl (1 6)-$\beta$-D-galactopyranoside, kaempferol-3-O-$\alpha$-L-rhamnopyranosyl (1 6)-$\beta$-D-galactopyranoside and quercetin-7-O-$\beta$-D-glucopyranosy-3-O-$\beta$-D-galactopyranoside were isolated by column chromatographic separation using Amberlite XAD-2 and Sephadex LH-20, and identified physicochemical evidences (IR, FAB-Mass, $^1H,{\;}^{13}C-NMR$).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.5
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• pp.748-754
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• 2000

A novel single feed wide band CP stacked microstrip antenna using crossed slots has been designed, fabricated and measured. For the single rediating element the designed 10dB return loss bandwidth is 34.5%99.45~13.54 GHz), 3dB axial ratio bandwidth is 18.7%(11.17~13.39GHz), and 6 dB gain bandwidth is 29%(10.21~13.64GHz). For the 2$\times$2 array designed using a sequential rotation method, the 10dB return loss bandwidth is 35.9%(9.69~13.94GHz), 3dB axial ratio bandwidth is 34.6GHz (9.93~14.03GHz), and 6dB gain bandwidth is 27.4%(10.35~13.6GHz). For the fabricated 8$\times$8 array antenna, the 10dB return loss bandwidth is 27.3%(10.17~13.41GHz), 3dB axial ratio bandwidth is 27.9GHz(10.1~13.4GHz), and the radiation pattern is good agreement with theory. This antenna can be used for broadband applications for communications or broadcasting in Ku band.

• Journal of Korean Ophthalmic Optics Society
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• v.9 no.2
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• pp.323-332
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• 2004

This study researched the visual acuity test object and Auto-refractormeter, visual of near power. The object were composed of middle aged, the old men and women who in habit Daegu. The results were as follows : 1. The subjects consisted of 537 people, 29.98% men, 70.02% women. 2. The emmetropia was 1.12% for myopia, 2.79% for hyperopia, 96.09% for astigmatism. 3. The abnormal refraction was composition for myopic compound astigmatism(16.57%), hyperopia compound astigmatism(45.62%), Mixed astigmatism(33.89%). 4. On the Myopic Spherical Equivalent(S.E) power, the range of -0.50D ${\leq}$ M.S.E < -1.00D was 21.67%, -1.00D ${\leq}$ M.S.E < -2.00D was 48.89%, -2.00D ${\leq}$ M.S.E < -6.00D was 29.44%. 5. On the Hyperopic Spherical Equivalent(S.E) power, the range of +0.50D ${\leq}$ H.S.E < +1.00D was 28.57%, +1.00D ${\leq}$ H.S.E < +2.00D was 49.30%, +2.00D ${\leq}$ H.S.E < +6.00D was 23.13%. 6. The addition power was 1.00D(8.01%), 1.50D(8.57%), 2.00D(13.78%), 2.50D(16.57%), 3.00D(16.95%), 3.50D(17.88%), 4.00D(18.25%).

• Journal of Broadcast Engineering
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• v.12 no.6
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• pp.641-648
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• 2007

The decoding structure of up-to-date ATSC DTV receivers is well optimized, and it seems that 14.6 dB is the unbreakable minimum SNR in the AWGN channel. But the SNR satisfying the Shannon capacity of DTV receivers is 11.76 dB, So, the SNR gab between the 14.6 dB and the 11.76 dB is about 2.8 dB. In order to approach the Shannon capacity we propose a recursive trellis decoder which uses reliable feedback data obtained by an RS decoder. The performance enhancement of about 0.8 dB can be achieved in case of the AWGN channel.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.645-654
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• 1999

Interleukin-6(IL-6) stimulate osteoclast differentiation. $17{\beta}$-estradiol, 1,25-dihydroxyvitamin $D_3$(1,25-$(OH)_2D_3$) and interleukin-$1{\beta}$ inhibit or stimulate osteoclast differentiation by decreasing or increasing the synthesis of interleukin-6(IL-6) from stromal/osteoblastic cells, respectively. Periodontal ligament(PDL) cells reside between the alveolar bone and the cementum and have osteoblastic characteristics. To estimate the effect of $17{\beta}$-estradiol and 1,25$(OH)_2D_3$ on IL-6 production of PDL cells, PDL cells were treated with $17{\beta}$-estradiol or 1,25-$(OH)_2D_3$ in the absence or the presence of IL-$1{\beta}$. The concentration of IL-6 produced form PDL cells was determined by enzym linked immunosorbent assay(ELISA). In unstimulated PDL cells, we detected constitutive production of IL-6 at 1st and 2nd day. IL-$1{\beta}$ increased IL-6 synthesis at 1st day and 2nd day. $17{\beta}$-estradiol had no significant effect on the secretion of this cytokine, either constitutively or after stimulation with IL- $1{\beta}$(0.05 ng/ml). 1,25-$(OH)_2D_3$($10^{-8}M$) decreased not only constitutive IL-6 production but also IL-$1{\beta}$-induced IL-6 production at 2nd day. These results suggest that 1,25-$(OH)_2D_3$ may control IL-$1{\beta}$-induced osteoclast differentiation by decreasing IL-$1{\beta}$-induced IL-6 secretion of PDL cells.

• Food Engineering Progress
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• v.21 no.2
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• pp.103-109
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• 2017

Alginate lyase from Streptomyces violaceoruber was purified by DEAE sephacel chromatography and SP sepharose chromatography. The specific activity of the purified enzyme was 14.6 units/mg protein, representing a 40.6-fold purification of the crude extract. The final preparation thus obtained showed a single band on Tricine-SDS polyacrylamide gel electrophoresis whose molecular weight was determined to be 23.3 kDa. The polyMG block of sodium alginate was hydrolyzed by the purified alginate lyase and then separated by activated carbon column chromatography and bio gel P-2 gel filtration. The main hydrolysates were composed of hetero type M/G-oligosaccharides with the degrees of polymerization (D.P.) being 6 and 8. To investigate the effects of hetero type M/G-oligosaccharides from the sodium alginate on the growth of some intestinal bacteria, cells were cultivated individually on the modified-MRS medium containing D.P. 6 and 8 M/G-oligosaccharides. B. longumgrew 4.25-fold and 6.44-fold more effectively by the treatment of D.P. 6 and 8 M/G-oligosaccharides compared with those of standard MRS medium. In addition, B. bifidumgrew 3.3-fold and 5.4-fold more effectively by the treatment of D.P. 6 and 8 M/G-oligosaccharides. In conclusion, D.P. 8 was more effective than D.P. 6 hetero M/G-oligosaccharides as regards the growth of Bifidobacteriumspp. and Lactobacillus spp.

• Journal of IKEEE
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• v.22 no.4
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• pp.1012-1018
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• 2018

In this paper, CMOS SAR (Successive Approximation Register) A/D converter with 1.8V supply voltage is designed for IoT sensor processing. This paper proposes design of a 12-bit SAR A/D converter with two A / D converters in parallel to improve the sampling rate. A/D converter1 of the two A/D converters determines all the 12-bit bits, and another A/D converter2 uses the upper six bits of the other A/D converters to minimize power consumption and switching energy. Since the second A/D converter2 does not determine the upper 6 bits, the control circuits and SAR Logic are not needed and the area is minimized. In addition, the switching energy increases as the large capacitor capacity and the large voltage change in the C-DAC, and the second A/D converter does not determine the upper 6 bits, thereby reducing the switching energy. It is also possible to reduce the process variation in the C-DAC by proposed structure by the split capacitor capacity in the C-DAC equals the unit capacitor capacity. The proposed SAR A/D converter was designed using 0.18um CMOS process, and the supply voltage of 1.8V, the conversion speed of 10MS/s, and the Effective Number of Bit (ENOB) of 10.2 bits were measured. The area of core block is $600{\times}900um^2$, the total power consumption is $79.58{\mu}W$, and the FOM (Figure of Merit) is 6.716fJ / step.

• Natural Product Sciences
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• v.16 no.4
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• pp.207-210
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• 2010

Phytochemical investigation of Salvia plebeia resulted in the isolation of nine compounds. Their structures were determined to be 6-methoxynaringenin (1), 6-methoxynaringenin-7-O-$\beta$-D-glucoside (2), hispidulin (3), homoplantaginin (4), nepetin (5), nepitrin (6), 6-hydroxyluteolin (7), caffeic acid (8) and rosmarinic acid (9) by spectroscopic analyses. 6-Methoxynaringenin (1), 6-hydroxyluteolin (7) and rosmarinic acid (9) were isolated from this plant for the first time.

• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.185-188
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• 2001

We have developed a synthetic method for dTDP-4-keto-6-deoxy-D-glucose with four enzyme system. We have used crude extracts from cultures of Escherichia coli BL21 strains harboring plasmids containing different sources. dTDP-4-keto-6-deoxy-D-glucose was synthesized by the combination of thymidine-monophosphate kinase, acetate kinase, dTDP-glucose synthase and dTDP-D-glucose 4,6-dehydratase in a batch system, starting the reaction with dTMP. The enzymatic synthesis strategy allowed a dTMP conversion with a 95%.

• Proceedings of the KIEE Conference
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• 2003.07c
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• pp.1867-1869
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• 2003

In this paper, chamber(Circuit breaker compartment of C-GIS) made of stainless steel with 4 mm width is used. Artificial defect was made on enclosure or HV conductor of chamber and $SF_6$ gas was injected into it according to pressure. In this experiment, Acoustic emission sensors of different types was used to compare sensitivity to detect acoustic signal occurred by Partial discharge(PD) of according to types and resonance frequency in $SF_6$ gas atmosphere. Sensors used in tests was R6I, R15I and 2/4/6 Pre-Amplifier connected with R6IU without pre. amp. In case of R6IU, gain was adjusted with 40 dB like other sensors and operated by differential mode. Post amplifier(post. amp) and band pass filter(BPF) were developed Gain of post. amp. is 60 dB and BPF has band width of $50{\sim}300$ kHz. Also, envelope circuit developed reduces frequency of AE sensor. As a result, in $SF_6$ atmosphere, R6IU and R6I had resonance frequency of 60 Hz was better than R15I. Also, R6IU was better than R6I because of type property of pre.amp. had differential mode.