• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.379-387
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• 2004

When an organism is exposed to various toxicants chronically, reactive oxygen species(ROS) are accumulated and eventually result in several biological effects from gene expression to cell death. In the present study we investigated the oxidative damage of 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin(TCDD) and/or benzo(a)pyrene (B(a)P) in C100 cells. C100 cells treated with TCDD(30 nM) and B(a)P($3{\mu}M$) underwent diverse oxidative stress as determined through thiobarbituric acid-reactive substances(TBARS) formation, DNA fragmentation, DNA single strand break(SSB) assay, immunohistochemical staining of 8-hydroxy-2'-deoxyguanosine(8-OHdG), and mRNA expressions of antioxidant enzymatic genes such as Cu/Zn-SOD gene, GPx(glutathione peroxidase 5) gene, and catalase gene. Lipid peroxidation in C100 cells was determined through measuing the formation of TBARS. For theat, the cells were pretreated with TCDD(30 nM) and/or B(a)P($3{\mu}M$) for 0.5, 1, 2 and 4 days. TBARS formation was increased in TCDD(30 nM) and B(a)P($3{\mu}M$) and mixture($30nM\;TCDD+3{\mu}M\;B(a)P$) and positive control treatment groups comparing to the controls. Mixture treatment induced more DNA fragmentation than the single treatment group at day 6. Also, SSB in all treatment groups was clearly observed when compared with the negative control group. As with the expression of antioxidant enzyme, GPx 5mRNA, B(a)P alone and mixture($30nM\;TCDD+3{\mu}M\;B(a)P$) treatment were higher comparing to those of the negative control and TCDD treatment groups. Our results suggest that exposure of C100 cells to mixture of TCDD and B(a)P leads to significant oxidative damage comparing to the exposures to the individual chemicals. Mechanisms of action are discussed. Additional studies are needed to elucidate the detailed mechanism of mixture-induced toxicity.

• Food Science and Preservation
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• v.20 no.1
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• pp.37-44
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• 2013

To investigate the usability of the bitterns produced during salt manufacture, the characteristics of soybean curds coagulated with bitterns like solar salt bitterns (SSB), dehydrated salt bitterns (DSB), concentrated sea water (CSW) and bitterns produced during the storage of solar salt (BSS) were measured. The Mg contents of all the bitterns were the same, but the Na content of the BSS was 1.0-2.0 times as high as that of the other bitterns. The yield of the soybean curds did not differ with the addition of coagulants, except for the CSW. However, the soybean curds were acquired in large quantities by the DSB and CSW. The mg and Na contents of the soybean curds that were made with the bitterns were higher than those of $MgCl_2$. The heavy metals were below 3 ppm in the curds, especially those produced by the CSW, but Pb was not detected. Among the mechanical characteristics of the soybean curds, their adhesiveness was not affected by the coagulants, but the mechanical hardness of the curds produced by the DSB and CSW was lower. The sensory evaluation showed that the curds that were produced by the bitterns were more highly preferred than those produced by $MgCl_2$. In particular, the soybean curd that was made with the CSW was favored due to its soft texture. The results of this study, particularly the high yield of the curds that showed a soft texture, showed that the bitterns, especially the CSW, could be used safely and economically.

• Journal of IKEEE
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• v.7 no.2 s.13
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• pp.236-244
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• 2003

In this paper, RF and IF circuits for mobile terminals which have usually been implemented using expensive BiCMOS processes are designed using CMOS circuits, and a Tx CMOS RF/IF single chip for PCS applications is designed. The designed circuit consists of an IF block including an IF PLL frequency synthesizer, an IF mixer, and a VGA and an RF block including a SSB RF mixer and a driver amplifier, and performs all transmit signal processing functions required between digital baseband and the power amplifier. The phase noise level of the designed IF PLL frequency synthesizer is -114dBc/Hz@100kHz and the lock time is less than $300{\mu}s$. It consumes 5.3mA from a 3V power supply. The conversion gain and OIP3 of the IF mixer block are 3.6dB and -11.3dBm. It consumes 5.3mA. The 3dB frequencies of the VGA are greater than 250MHz for all gain settings. The designed VGA consumes 10mA. The designed RF block exhibits a gain of 14.93dB and an OIP3 of 6.97dBm. The image and carrier suppressions are 35dBc and 31dBc, respectively. It consumes 63.4mA. The designed circuits are under fabrication using a $0.35{\mu}m$ CMOS process. The designed entire chip consumes 84mA from a 3V supply, and its area is $1.6㎜{\times}3.5㎜$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.6 s.121
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• pp.602-611
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• 2007

In this paper, the forward link of UHF RFID system is modeled in accordance with the EPCglobal class 1 generation 2(EPCglobal C1G2) UHF Radio-Frequency Identity protocol specification at $860{\sim}960MHz$. Based on the constructed model, characteristics on the forward link signal for the EPCglobal C1G2 RFID reader are simulated with the help of a MATLAB softwarein order to extract the design parameters of a transmit digital filter which meets the Korean RFID regulations. Herein, the forward link model is consisted of PIE source coding, transmit digital filter, modulation, local oscillator, and antenna. From the simulation results, the ranges of three design parameters(roll-off factor, cutoff frequency, the number of tabs) for transmit digital filter are obtained with different modulation techniques and the Tari(type a reference interval) values. Finally, DSB/SSB-ASK modulation technique can not satisfy the EPCglobal C1G2 specification when Tari equals to $6.25{\mu}sec$ in a multiple-reader environment. Consequently this paper can provide a guideline for design parameters of a RFID reader as well as the basic scheme of analyzing frequency interference problems in RFID environments, including multiple-reader and dense-reader environments.

• Clinical and Experimental Pediatrics
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• v.48 no.3
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• pp.342-345
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• 2005

Neonatal lupus erythematosus(NLE) is a distinct subset of lupus characterized by cutaneous findings, cardiac conduction defects, hepatic or hematologic abnormalities. These manifestations are associated with the presence of maternal auto-antibodies such as anti-SSA/Ro, anti-SSB/La, and rarely anti-RNP($U_1RNP$) antibodies. Cases of $U_1RNP$ antibody-positive NLE have somewhat atypical cutaneous manifestation without cardiac or systemic abnormalities. We report a case of cutaneous NLE associated with $U_1RNP$ antibodies.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.5
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• pp.9-14
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• 2013

This paper is designed frequency multiplier with low phase noise using DLL technique. The VCDL is designed using a differential structure to reduce common-mode noise. The proposed frequency multiplier is fabricated in a 65nm, 1.2V TSMC CMOS process, and the operating frequency range from 10MHz to 24MHz was measured. The SSB phase noise is measured to be -125dBc/Hz at 1MHz from 38.4MHz carrier. A total area of $0.032mm^2$were consumed in the chip, including the output buffer. Total current is 1.8mA at 1.2V supply voltage.

• Neonatal Medicine
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• v.18 no.2
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• pp.391-394
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• 2011

Neonatal lupus erythematosus (NLE) is a rare disease characterized by typical clinical features and the transplacental passage of maternal autoantibodies, particularly anti-SSA/Ro. The major clinical manifestations are cutaneous lupus lesions, congenital heart block, hematological disorders, and hepatobiliary diseases. We report a case of NLE presenting with multiple round and oval target-like erythematous skin lesions and abnormal liver function, born to a clinically asymptomatic mother whose diagnosis was made retrospectively only after her newborn's diagnosis. Both the infant and the mother were positive for the anti-SSA/Ro and anti-SSB/La antibodies.

• Steel and Composite Structures
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• v.13 no.4
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• pp.367-382
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• 2012

This paper is dedicated to the buckling behaviors of strengthened perforated plates under edge shear loading, which is a typical load pattern of steel plates in civil engineering, especially in plate and box girders. The square plates considered each has a centric circular hole and is simply supported on four edges in the out-of-plane direction. Three types of strengthening stiffeners named ringed stiffener (RS), flat stiffener (FSA and FSB) and strip stiffener (SSA, SSB and SSC) are mainly discussed. The finite element method (FEM) has been employed to analyse the elastic and elasto-plastic buckling behavior of unstrengthened and strengthened perforated plates. Results show that most of the strengthened perforated plates behave higher buckling strengths than the unstrengthened ones, while the enhancements in elastic buckling stress and elasto-plastic ultimate strength are closely related to stiffener types as well as plate geometric parameters including plate slenderness ratio and hole diameter to plate width ratio. The critical slenderness ratios of shear loaded strengthened perforated plates, which determine the practical buckling pattern (i.e., elastic or elasto-plastic buckling) of the plates, are also studied. Based on the contrastive analyses of strengthening efficiency considering the influence of stiffener consumption, the most efficient cutout-strengthening methods for shear loaded perforated square plates with different slenderness ratios and circular hole diameter to plate width ratios are preliminarily identified.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.192-195
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• 2013

Commercialization of AIS, it make be possible to provide VTS service efficiency and to decide quickly navigational action among vessels. Communications at sea mostly doing by communicating equipments(SSB, VHF, etc.). Especially, it is impossible to provide VTS service to non-listening vessels and non-reponse vessels. These vessels are main reason that make the problems communcating among vessels at sea. Solution of these, Displaying stand by channel of each vessels in real time, it can be improve response rate(factor) to non-listening vessels and non-response vessels. It will bhe helpful to improve safety at sea.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.66.1-66.1
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• 2012

We have developed superconducting mixer receivers for 129 GHz VLBI observation in Korean VLBI Network(KVN). The developed mixer has a radial waveguide probe with simple transmission line LC transformer as a tuning circuit to its 5 series-connected junctions, which can have 125-165 GHz as operation RF frequency. For IF signal path a high impedance quarter-wavelength line connects the probe to one end of symmetric RF chokes. DSB receiver noise of the mixer was about 40 K over 4-6 GHz IF band whereas we achieved about uncorrected SSB noise temperature of 70 K and better than 10 dB IRR in 2SB configuration with 8-10 GHz IF band. Insert-type receiver cartridges using the mixers have been assembled for all three KVN stations. On-site performance summary in commissioning phase is presented.