• Environmental Engineering Research
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• v.23 no.1
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• pp.1-9
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• 2018

The degradation of methylene blue (MB) in an aqueous solution by nano-metallic particles (NMPs) was studied to evaluate the possibility of applying NMPs to remove MB from the wastewater. Scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to characterize the synthesized NMPs before and after the reaction. The effects of the NMP dosage, the initial pH, the initial concentration of MB and the amount of $H_2O_2$ on the MB degradation outcomes were studied. The highest removal rate of MB was achieved to be 100% with an initial MB concentration of 5 mg/L, followed by 99.6% with an initial concentration of 10 mg/L under the following treatment conditions: dose of NMP of 0.15 g/L, concentration of $H_2O_2-100mM$ and a temperature of $25^{\circ}C$. The SEM analysis revealed that the nano particles were not spherical in shape. FTIR spectra shows occurrence of metal oxides on the surfaces of the NMPs. The XPS analyses results represent that Fe, Zn, N, Ca, C and O were occurred on the surfaces of the NMPs. The degradation of MB was suitable for the pseudo-first-order kinetics.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.10A
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• pp.1177-1188
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• 2004

This paper describes and analyzes the performance of MB-OFDM UWB system that is suggested as one of standards in IEEE 802.15 TG3a for UWB application. UMBchannel model that has been contributed in IEEE 802.15 SG3a is a wideband channel model of 6Ghz bandwidth, so we modify it to have 3 subband channels that are obtained by filtering conventional U Channel, considering center frequency hopping and system bandwidth. From simulations, we compare performances of MB-OFDM system in AWGN and WB channel and verify the frequency and time domain diversity gains from time End frequency spreading technique. We also compare and analyze the performance of proposed SFBC MB-OFDM with that of conventional MB-OFDM system. Simulation results show SFBC MB-OFDM system outperforms conventional MB-OFDM system about 1.5dB of Eb/No at target BER of 10$^{-m4}$./.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.1A
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• pp.47-53
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• 2003

This paper describes the design of a 155 Mb/s multiplexer-demultiplexer chip. This device for a 2.5 Gb/s SDH based transmission system is to interleave the parallel data of 51 Mb/s into 155 Mb/s serial data output, and is to deinterleave a serial input bit stream of 155 Mb/s into the parallel output of 51 Mb/s The input and output of the device are TTL compatible at the low-speed end, but 100K ECL compatible at the high-speed end The device has been fabricated with a 0.7${\mu}m$ BiCMOS gate array The fabricated chip shows the typical phase margin of 180 degrees and output data skew less than 470 ps at the high-speed end. And power dissipation is evaluated under 2.0W.

• Journal of Chest Surgery
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• v.35 no.1
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• pp.27-35
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• 2002

Background: A perioperative myocardial infarction(PMI) is one of the major complications after CABG. Among diagnostic methods of PMI, CK-MB activity assays have been increasingly replaced by CK-MB mass assays, which have more sensitive, simple measurement. Also, new cardiac-specific and -sensitive marker, cardiac troponin I(cTnl), has been shown to be a marker of myocardial infarction. We report our evaluation of clinical significance of CK-MB mass and cTnl as a marker of PMI after CABG. Material and Method: We studied 32 patients who underwent CABG at Kangdong Sacred Hospital between April 2000 and April 2001. Postoperative serum CK-MB activity level, serum CK-MB mass, cTnl, electrocardiogram, echocardiogram, and clinical data were recorded prospectively The diagnosis of PMI was defined as positive 2 among 3 or all of the following , by a new Q wave on the electrocardiogram, by serum CK-MB activity higher than 200 lU/L within 72 hours after operation, and by new regional wall motion abnormality on the echocardiogram. Result: After CABG, 3 patients had sustained a PMI according to current diagnostic criteria. As serum CK-MB activity time course, a level of CK-MB activity 12 hours after CABG had very linear correlated significance with serum CK-MB mass 24hours(R=0.946) and cTnl 48 hours(R=0.933) after CABG(p=0.000). As we used a receiver operating characteristics curve(ROC curve) for a diagnostic cutoff value in patients with PMI, serum CK-MB mass levels higher than 30.05 ug/L 24 hours after CABG detected the presence of PMI with an area under the ROC curve of 1.0, a sensitivity of 100%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 100%. Also serum cTnl levels higher than 17.15 ug/L 48 hours after CABG detected the presence of PMI with an area under the ROC curve of 0.98, a sensitivity of 100%, a specificity of 96.6%, a positive preclictive value of 75%, and a negative predictive value of 100% Conclusion: We concluded that both the measurement of CK-MB mass and cTnl are the easier, accurate methods as a diagnostic marker of PMT after CABG, also as a proposal of diagnostic cutoff value enables to an early detection of PMI. However, a 1arger number of patient will be needed because of statistic limitation that a small number of participating patients, a small number of PMI.

• Journal of Veterinary Clinics
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• v.9 no.2
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• pp.433-449
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• 1992

Total CPK activities and CPK isoenzymes fractions of the sera and tissues were examined to obtain the physiological basic data of ruminant available in veterinary clinical practice. For the sera total CPK activities and CPK isoenzymes fractions, total 39 clinically healthy Korean native goats (3 to 10 months old, IS of female and 18 of male) and 6 of Korean native goats (1 to 2 years old, 3 of female and 3 of male) were used. Seventeen Korean native cattle (3 to 6 years old, 10 of female and 7 of male) and 27 Holstein-Friesian cattle (2 to 8 months old, 7 of female and 3 to 12 years old, 20 of female) were also examined for the sera total CPK activities and CPK isoenzymes fractions. For the total CPK activities and CPK isoenzyme fractions, 3 of female Korean native goats (7 months old), 3 of female Korean native cattle (2 years old) and 3 of dairy cattle (2 years old, 2 of female and 1 of male) were used. The tissues examined were the cerebrum (2 of Korean native cattle), spinal cord (1 of Korean native cattle), heart, lung, diaphragm, reticulum, liver, spleen, kidney, jejunum. colon and femoral muscle. The results obtained were as follows : 1. In Korean native goats less than 1-year-old. serum total CPK activities were 67.8${\pm}$17.7(39.0~96.5) IU/$\ell$ in female and 63.4${\pm}$19.0(28.7~94.4) IU/$\ell$ in male. Further they were 67.0${\pm}$5.3(59.5~70.7) IU/$\ell$ and 54.5${\pm}$11.1(39.1~69.4) IU/$\ell$ in female and male Korean native goats over 1-year-old, respectively. Serum total CPK activities of female were slightly higher than those of male. Significance between age and sex was not found. 2. Serum total CPK activities were 56.8${\pm}$19.7(27.6~90.5) IU/$\ell$ and 65.6${\pm}$10.8(52.8~78.0) IU/$\ell$ in female and male Korean native adult cattle, respectively, Serum total CPK activities of male were slightly higher than those of female, but they were not significant 3. Serum total CPK activities we,e 72.5${\pm}$8.2(57.2~83.2) IU/$\ell$ and 60.8${\pm}$12.5(42.7~80.6) IU/$\ell$ in calves and adult of dairy acttle, respectively. Serum total CPK activities of calves were significantly higher than those of adult(p<0.05). 4. In Korean native goats less than 1-year-old, serum CPK isoenzymes fractions were high with decreasing order of MM>MB>BB and MM>BB>MB in female and male, respectively. Further they were high with decreasing order of MM>MB>BB and MM>B8>MB in female and male Korean native goats over 1-year-old, respectively. The main fractions of CPK isoenzymes were MM in sera of Korean native goats. 5. Serum CPK Isoenzyme fractions were high with decreasing order of MM>MB>BB In both female and male of Korean native cattle. The main fraction among them was MM. 6. Serum CPK isoenzymes fractions were high with decreasing order of MM>BB>MB in both calves and adult of dairy cattle. The main fraction among them was MM. 7. Total CPK activities were high with decreasing order of the femoral muscle>kidney>reticulum>diaphragm>liver>spleen>heart>colon>lung>jejunum in Korean native goats. 8. Total CPK activities were high with decreasing order of the spinal cord >cerebrum>femoral muscle>reticulum>kidney>liver>spleen>diaphragm>lung>colon>heart>jejunum in Korean native cattle. 9. Total CPK activities were high with decreasing order. of the femoral muscle >liver>retoculum>kidney>heart>colon>lung>spleen>jejunum>diaphrasm in dairy cattle. 10. The pattern of the cardiac CPK isoenzymes fractions was identical in Korean native goats, Korean native cattle and dairy cattle. They were high in the order of MM>MB without BB fractions and the main fraction was MM. 11. The pattern of the pulmonary CPK isoenzymes fractions was the same Korean native goats, Korean native cattle and dairy cattle. They were high with decreasing order of MM>MB>BB and the main fraction among them was MM. 12. The pattern of CPK isoenzymes fractions of the diaphragm was Identical in Korean native goats and Korean native cattle. They were high with decreasing order of MM >BB >MB except dairy cattle (MM>MB>BB) but the main fraction among them was MM. 13. The pattern of the reticular CPK isoenzymes fractions was identical in Korean native cattle and dairy cattle. They were high with decreasing order of BB >MM >MB except Korean native goats(BB>MB>MM) but the main, fraction among them was BB 14. The pattern of the hepatic CPK isoenzymrs fractions was identical in Korean native cattle and dairy cattle. They were high with decreasing order of MB >BB >MM except Korean native goats(MB>MM>BB)but the main fraction was MB. 15. The splenic CPK isoenzymes fractions showed different pattern. They were high with decreasing order of MB>BB>MM, MM>BB>MB and BB>MB>MM in Korean native goats, Korean native cattle and dairy cattle, respectively. The main fraction among them was different from each other. 16. The pattern of the renal CPK isoenzymes fractions was identical in Korean native cattle and dairy cattle. They were high with decreasing order of MM >MB>BB except Korean native goats(BB>MB>MM). 17. The CPK isoenzymes fractions of the Jejunums showed different pattern. They were high with decreasing order MM>MB>BB, MM>BB>MB and BB>MM>MB in Korean native goats, Korean native cattle and dairy cattle, respectively. The main fractions were MM In Korean native goats and Korean native cattle, and BB in dairy cattle. 18. The colonic CPK isoenzymes fractions showed different pattern. They were high with decreasing order of MM>MB>BB, MM>BB>MB and BB>rrfB>MM in Korean native goats, Korean native cattle and dairy cattle, respectively. The main fractions were MM in Korean native goats and Korean . native cattle, and BB in dairy cattle. 19. The cerebral CPK isoenzymes fractions were high with decreasing order of BB >MM without MB detected in Korean native cattle and those of spinal cord were high with decreasing order of BB >MM >MB. The main fractions in both cerebrum and spinal cord were BB.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.935-938
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• 2008

DoS/DDoS 공격과 웜 공격으로 대표되는 트래픽 폭주 공격은 그 특성상 사전 차단이 어렵기 때문에 빠르고 정확한 탐지는 공격 탐지 시스템이 갖추어야 할 필수요건이다. 기존의 SNMP MIB 기반 트래픽 폭주공격 탐지 방법은 1 분 이상의 탐지 시간을 요구하였다. 본 논문은 SNMP MIB 객체의 상관 관계를 이용한 빠른 트래픽 폭주 공격 탐지 알고리즘을 제안한다. 또한 빠른 탐지 시간으로 발생되는 시스템의 부하와 탐지 트래픽을 최소화하는 방안도 함께 제시한다. 공격 탐지 방법은 3 단계로 구성되는데, 1 단계에서는 MIB 정보의 갱신주기를 바탕으로 탐지 시점을 결정하고, 2 단계에서는 MIB 정보간의 상관 관계를 이용하여 공격의 징후를 판단하고, 3 단계에서는 프로토콜 별 상세 분석을 통하여 공격 탐지뿐만 아니라 공격 유형까지 판단한다. 따라서 빠르고 정확하게 공격을 탐지할 수 있고, 공격 유형을 분류해 낼 수 있어 신속한 대처가 가능해 질 수있다.

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.330-335
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• 2019

The aim of this study was to investigate the rheological properties of arabinogalactans (AGs) solution isolated from moth bean (MB), navy bean (NB), and soybean (SB) including monosaccharide compositions, intrinsic viscosity, steady shear and dynamic shear rheological properties. The major monosaccharides in MB, NB, and SB were arabinose (64.8, 51.4, and 42.6%) and galactose (13.4, 19.6, and 46.2%). The yield stresses for 5% (w/v) NB and 2.5% (w/v) SB solutions were assessed as 2.10 Pa and 1.98 Pa, respectively, but in case of MB solution, it was observed to be negligible. While 5% MB solution showed rheopectic property, 5% NB and SB solutions showed thixotropic properties. As a result of frequency sweep experiment, the G' values in 2.5% MB and NB were larger than the G" value showed but 2.5% SB exhibited G" value greater than G'. These results would be useful for future application as a food additive in the food industry.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.4
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• pp.25-31
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• 2017

This paper presents a 270/540/750/1500-Mb/s serial-data transmitter realized in a $0.13-{\mu}m$ CMOS technology for the applications of video data transmission. A low-cost RG-58 copper cable(5C-HFBT-RG6T) is exploited as a transmission medium connected to a single BNC connector, which shows cable loss 45 dB in maximum at 1.5 GHz. RLGC modeling provides an equivalent circuit for SPICE simulations of which characteristics are very similar to the measured cable loss. The loss can be compensated by pre-emphasis at transmitter and equalization at receiver if needed. Measurements of the proposed transmitter chip demonstrate the operations of 270-Mb/s, 540-Mb/s, 750-Mb/s and 1.5-Gb/s, and provide the output voltage levels of $370mV_{pp}$ at 1.5 Gb/s even with the pre-emphasis turned-off. The total power consumption is 104 mW from 1.2/3.3-V supplies and the chip occupies the area of $1.65{\times}0.9mm^2$.

• Journal of IKEEE
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• v.13 no.4
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• pp.70-74
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• 2009

In this paper, We propose the visible light communication(VLC) link based on white light emitting diode (LED) and Photo detector(PD). The proposed architecture is demonstrated experimentally and its performance is verified through the experimental results of quality-factor(Q-factor) and eye pattern of 10Mb/s PRBS signal. The ambient light effect from a typical type fluorescent lamp source was also analyzed. when the distance between the LED and the PD is about 1m, error free wireless transmission of the LED was achieved up to 10Mb/s data rate. Under the condition with ambient light, low BER, data transmission of the VLC link is achieved up to 5Mb/s data rate at 1m. Also, when the PD is placed away from the center, low BER data transmission of the VLC link is achieved up to 1Mb/s at 10cm and 10Mb/s at 5cm.

• Analytical Science and Technology
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• v.26 no.5
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• pp.326-332
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• 2013

Geosmin and 2-methylisoborneol (2-MIB) are volatile organic compounds responsible for the majority of unpleasant taste and odor events in drinking water. Geosmin and 2-MIB are byproducts of blue-green algae (cyanobacteria) with musty and earthy odors. These compounds have odor threshold concentration at ng/L levels. It is needed to develop a sensitive method for determination of geosmin and 2-MIB to control the quality of drinking water. In this study, geosmin and 2-MIB in water samples were determined by gas chromatography-mass spectrometry (GC-MS) with headspace-solid phase microextraction (HS-SMPE). The detection limits of this method were 1.072 ng/L and 1.021 ng/L for geosmin and 2-MIB, respectively. Good accuracy and precision was also obtained by this method. Concentrations of the two compounds were measured in raw waters from Nakdong River in the cyanobacterial blooming season. Water bloom formed by cyanobacteria has been occurred currently in Nakdong River. It is needed to investigate the concentrations of geosmin and 2-MIB to control the quality of drinking water from Nakdong River. Both geosmin and 2-MIB were detected in raw waters from Nakdong River at concentrations ranging from 4 to 24 ng/L and 6 to 16 ng/L, respectively.