• Korea Petroleum Association Journal
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• no.7 s.249
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• pp.66-76
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• 2005

●2004년 세계 석유 소비는 8천75만7천 b/d로 전년대비 3.4% 증가하여 1978년 이래 최고상승률을 기록했다. 소비 비중은 미국이 전체의 24.9%를 점유하여 1위를 차지했고 중국(8.2%), 일본(6.4%), 러시아연방(3.4%), 독일(3.3%), 인도(3.2%), 한국(2.8%)순으로 나타났다. ●석유소비증가량은 중국이 전년대비 무려 15.8%인 246만 3천b/d증가하였고 미국은 2.8%인 48만 4천 b/d 증가한 반면 일본은 3.0%인 16만 7천 b/d감소하는 등 전체적으로 246만 7천 b/d증가하였다. ●세계석유생산은 8천 26만 b/d로 전년대비 4.5% 증가하였고 생산량 순으로는 사우디아리비아가 전체의 13.1%를 점유하여 1위를 차지하였고, 러시아연방(11.9%), 미국(8.5%), 이란(5.2%), 멕시코(4.9%), 중국(4.5%) 순으로 나타났다. ●세계석유매장량은 1조 1,886억 배럴로 가채년수는 405년이며 국가별로는 사우디아라비아가 전체의 22.1%를 점유하여 1위를 차지하였고 이란(11.1%), 이라크(9.7%), 쿠웨이트(8.3%), UAE(8.2%), 베네수엘라(6.5%), 러시아연방(6.1%) 순으로 나타났다. ●세계정제능력은 8천 459만 2천b/d로 전년대비 0.8% 증가하였다. 국가별로는 미국이 전체의 20.1%를 점유하여 1위를 차지하였고 중국(6.9%), 러시아연방(6.4%), 일본(5.4%), 한국(3.1%) 순으로 나타났다.

• Parasites, Hosts and Diseases
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• v.52 no.1
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• pp.93-97
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• 2014

Subolesin (4D8), the ortholog of insect akirins, is a highly conserved protective antigen and thus has the potential for development of a broad-spectrum vaccine against ticks and mosquitoes. To date, no protective antigens have been characterized nor tested as candidate vaccines against Dermacentor silvarum bites and transmission of associated pathogens. In this study, we cloned the open reading frame (ORF) of D. silvarum 4D8 cDNA (Ds4D8), which consisted of 498 bp encoding 165 amino acid residues. The results of sequence alignments and phylogenetic analysis demonstrated that D. silvarum 4D8 (Ds4D8) is highly conserved showing more than 81% identity of amino acid sequences with those of other hard ticks. Additionally, Ds4D8 containing restriction sites was ligated into the pET-32(a+) expression vector and the recombinant plasmid was transformed into Escherichia coli rosetta. The recombinant Ds4D8 (rDs4D8) was induced by isopropyl ${\beta}$-D-thiogalactopyranoside (IPTG) and purified using Ni affinity chromatography. The SDS-PAGE results showed that the molecular weight of rDs4D8 was 40 kDa, which was consistent with the expected molecular mass considering 22 kDa histidine-tagged thioredoxin (TRX) protein from the expression vector. Western blot results showed that rabbit anti-D. silvarum serum recognized the expressed rDs4D8, suggesting an immune response against rDs4D8. These results provided the basis for developing a candidate vaccine against D. silvarum ticks and transmission of associated pathogens.

• Journal of Advanced Navigation Technology
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• v.13 no.1
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• pp.48-53
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• 2009

The CMOS RF front-end for Global Positioning System(GPS)are implemented in 1P8M CMOS $0.13{\mu}m$ process. The LNAs consist of LNA1 with high gain and low NF, and LNA2 with low gain and high IIP3 for supporting operation with active and passive antenna. the measured performances of both LNAs are 16.4/13.8 dB gain, 1.4/1.68 dB NF, and -8/-4.4 dBm IIP3 with 3.2/2 mA form 1.2 V supply, respectively. The quadrature downconversion mixer is followed by transimpedance amplifier with gain controllability from 27.5 to 41 dB. The front-end performances in LNA1 mode are 39.8 dB conversion gain, 2.2 dB NF, and -33.4 dBm IIP3 with 6.6 mW power consumption.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.3
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• pp.358-365
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• 2008

A differential-gain-controlled LNA is designed and implemented in 0.18 um CMOS technology for $3.1{\sim}4.8GHz$ UWB system. In high gain mode, measurements show a differential power gain of $14.1{\sim}15.8dB,\;13.3{\sim}15dB$, respectably, an input return loss higher then 10dB, an input IP3 of -19.3 dBm, a noise figure of $4.85{\sim}5.09dB$, while consuming only 19.8 mW of power from a 1.8V DC supply. In low gain mode, measurements show a differential power gain of $-6.1{\sim}-4.2dB,\;-7.6{\sim}-5.6dB$, respectably, an input return loss higher then 10dB, an input IP3 of -1.45 dBm, a noise figure of $8.8{\sim}10.3dB$, while consuming only 5.4mW of power from a 1.8V DC supply.

• The Korean Journal of Vision Science
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• v.20 no.4
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• pp.413-420
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• 2018

Purpose : We present a novel method for the analysis of blue light applied by the analysis method of David L. with optical experiment and blue light by measuring the transmittance by dividing it by the refractive power in the spectacle lens made by MR8. Methods : The lenses of -8.00D, -7.00D, -6.00D, -5.00D, -4.00D, -3.00D, and 0.00D manufactured by MR8 being sold in the market, were selected. The transmittance was measured at the intervals of 5 nm from 200 to 1000 nm with UV-VIS Spectrophotometers (SolidSpec 3700), and they were in range of the blue light (380 to 500 nm) analyzed by a David L.'s analysis method. Results : All of the MR8 lenses selected for this study almost completely blocked at the UV range. A lens of -8.00D was measured as the lowest transmittance of 59.56% in the blue light area and low values were measured at the blue areas 1 and 2 according to the analysis of David L.In the infrared ray area, the transmittance of all lenses gradually decreased. The average value of the luminous transmittance was 23.67% ~ 26.33% and then gradually decreased from -4.00D. Conclusion : Applying the analysis of David L., a minimum of 41.28% and a maximum of 46.60% were measured at the blue light 1 area and a minimum of 87.30% and a maximum of 97.55% were measured at the blue light 2 area. A minimum of 86.83% and a maximum of 96.55% were measured at the blue light 3 area, and the average was 94%. The luminous transmittance of the -3.00D lens was 26.33%, which was the highest, and that -8.00D was 23.67%, which was the lowest.

• The Journal of Korean Institute of Information Technology
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• v.17 no.3
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• pp.31-41
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• 2019

In this paper, we design and implement the simulator for the transmitter and receiver of 4D-8PSK TCM with 2.0, 2.25, 2.5, and 2.75 bits/symbol-channel transmission efficiency recommended by the CCSDS for satellite communications, and then analyze the BER performance of 4D-8PSK TCM system in AWGN channel. The transmitter of 4D-8PSK TCM is designed in accordance with the recommendation in the CCSDS standard. Meanwhile, for the receiver design of 4D-8PSK TCM, we design the differential decoder generalizing the differential encoder/decoder scheme. The trellis decoding algorithm is designed by applying the auxiliary trellis information and the Viterbi algorithm, and an 8-dimensional constellation mapper equation given in the CCSDS standard is deconstructed to design constellation mapper. Especially, we present the optimized receiver for 4D-8PSK TCM system by investigating the BER performances for the traceback lengths in the Viterbi decoder through computer simulations..

• Journal of Advanced Navigation Technology
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• v.28 no.2
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• pp.232-237
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• 2024

In this paper, a broadband double dipole quasi-Yagi antenna using a 4×2 meander line array structure for maintaining 8 dBi gain was studied. The 4×2 meanderline array structure consists of a unit cell in the shape of a meanderline conductor, and it was placed above the second dipole antenna of the double dipole quasi-Yagi antenna. A double dipole quasi-Yagi antenna with generally used multiple strip directors was designed on an FR4 substrate with the same size, and the input reflection coefficient and gain characteristics were compared. Comparison results showed that the impedance frequency bandwidth increased by 6.3% compared to when using the multiple strip directors, the frequency bandwidth with a gain of 8 dBi or more increased by 10.1%, and average gain also slightly increased. The frequency band of the fabricated antenna for a voltage standing wave ratio less than 2 was 1.548-2.846 GHz(59.1%), and gain was measured to be more than 8 dBi in the 1.6-2.8 GHz band.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.1-5
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• 1998

This study describes the effect of the growth regulators such as 2,L-D and BA, on the structural abnormalities of somatic embryos derived from leaf explants of Angelica gigas Nakai, Also, the relationship between the cotyledon number of a somatic embryo and its germinability is explored. Embryogenic calli were selected from calli formed on explants cultured on MS solid basal medium supplemented with 0.5mg/L 2,4-D, 1mg/L 2,4-D, 1mg/L plus 0.1mg/L BA, and 1 mg/L 2,4-D plus 0.5mg/L BA. Cotyledonary abnormalities were observed in somatic embryos which were developed from embryogenic calli cultured on MS medium containing 1mg/L 2,4-D for 8 weeks and then subcultured on 2,4-D free MS medium for 3 weeks. The frequency of abnormalities was as follows: 22.8% one cotyledon, 42.5% two cotyledons, 16.8% three cotyledons, 7.8% four cotyledons, 1.8% five cotyledons, and 8.2% jar shaped cotyledon. In addition, ABA treatment indicated an improvement of the somatic embryo with normal cotyledon (65.3%). ABA was important role to the high production of normal somatic embryos. Two cotyledon embryos showed germinability 77.8%. However the germinability of somatic embryos with anomalous cotyledons was prominently low: One cotyledon, 62.5%; three cotyledons, 43.3%; four cotyledons, 60%; five cotyledons, 50% and jar shaped cotyledon, zero%. Thus, germinability was essentially, inversely proportional to cotyledon number.

• Archives of Pharmacal Research
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• v.26 no.2
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• pp.132-137
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• 2003

Three cerebrosides 2, 3, and 5 and two terpene glycosides 1 and 4 have been isolated from the methanol extract of the root of Aster scaber. Their structures were determined as 3-Ο-$\beta$-D-glucuronopyranosyl-oleanolic acid methyl ester (1), (2S, 3S, 4R, 2 R, 8Z, 15 Z)-N-2 -hydroxy-15 -tetracosenoyl-1-Ο-$\beta$-D-glucopyranosyl-4-hydroxy-8-sphingenine (2), (2S, 3S, 4R, 8Z)-N-octadecanoyl-1-Ο-$\beta$-D-glucopyranosyl-4-hydroxy-8-sphingenine (3), 1$\alpha$-hydroxy-6$\beta$-Ο-$\beta$-D-glucosyl-eudesm-3-ene (4), and (2S, 3S, 4R, 2 R, 8Z)-N-2 -hydroxy-hexadecanoyl-1-Ο-$\beta$-D-glucopyranosyl-4-hydroxy-8-sphingenine (5) on the basis of spectroscopic methods.

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.312-317
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• 2001

7'-Aldehyde-nucleosides analogue (2a, 2c) were synthesized from 6-N-benzoyl-2',3'-O-isopropylideneadenosine and uridine. The condensation of 2 with ethoxycarbonylmethylene Wittig reagent produced the adenosine and uridine analogues containing extended conjugated diene and ethoxycarbonyl group, ethyl-1',5',6',7',8'-pentadeoxy-1'-(adenin-9-yl)-$\beta$-D-ribo-nona-5'(E),7'(E)-dienofuranuronate (4b) and ethyl-1'. 5',6',7',8'-pentadeoxy-1'-(uracil-1-yl)-$\beta$-D-ribo-nona-5'(E),7'-(E)-dienofuranuronate (4c). 9-[8',8'-dibromo-5',6',7',8' -tetradeoxy-$\beta$-D-ribo-octa-5'(E),7'(E)-diene]nucleosides (6b, 6c) were also prepared from 2 with similar method.