• Journal of Institute of Control, Robotics and Systems
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• v.19 no.7
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• pp.646-652
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• 2013

EU's Galileo project is a market-based GNSS (Global Navigation Satellite System) that is under development. It is expected that Galileo will provide the positioning services based on new technologies in 2020s. Because Galileo E1 signal for OS (Open Service) shares the same center frequency with GPS L1 C/A signal, CBOC (Composite Binary Offset Carrier) modulation scheme is used in the E1 signal to guarantee interoperability between two systems. With E1 signal consisting of a data channel and a pilot channel at the same frequency band, there exist several options in designing signal acquisition for Assisted-Galileo receivers. Furthermore, compared to SNR worksheet of Assisted-GPS, some factors should be examined in Assisted-Galileo due to different correlation profile and code length of E1 signal. This paper presents SNR worksheets of Galileo E1 signals in E1-B and E1-C channel. Three implementation losses that are quite different from GPS are mainly analyzed in establishing SNR worksheets. In the worksheet, hybrid long integration of 1.5s is considered to acquire weak signal less than -150dBm. Simulation results show that the final SNR of E1-B signal with -150dBm is 19.4dB and that of E1-C signal is 25.2dB. Comparison of relative computation shows that E1-B channel is more profitable to acquire the strongest signal in weak signal environment. With information from the first satellite signal acquisition, fast acquisition of the weak signal around -155dBm can be performed with E1-C signal in the subsequent satellites.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.13-20
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• 2016

The computerized management system for bridges is required due to the increased service life and number of bridges. This paper provides information and communication technology (ICT) - based bridge management system (BMS) to enable life cycle management through a comparative study with the development trend and function of domestic and foreign BMSs. BMS developed as an operation system combined an internet and mobile program, and was based on GIS technology and an object-based information management system. BMS supports the establishment of long-term strategies and short-term plans based on predicting the life-cycle performance profile and the necessary budget by object-based informatization for the whole life-cycle information of bridges. Useful knowledge information for supporting decision making was derived from the life-cycle management strategies establishment for approximately 6,000 existing bridges. BMS was developed to be applicable to all nationwide road bridges. In addition, it can be used practically to maintain the performance based on accurate maintenance result management, reducing cost by reasonable budget management, and enhancing the convenience and reliability of field data collection.

• Journal of Species Research
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• v.5 no.1
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• pp.22-26
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• 2016

Five bacterial strains designated DY37, BS333, JJ521, BM1, and DG13-2 were assigned to the genus Deinococcus were isolated from forest soil samples collected from Deogyusan, Busan, Changwon, and Seoul of South Korea. The isolates were Gram-staining negative or positive, and pale pink- or red-pigmented, short-rod shaped. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strains DY37, BS333, JJ521, BM1, and DG13-2 were most closely related to Deinococcus aquatilis CCM $7524^T$ (with 99.0% similarity), D. ficus CC-FR2-$10^T$ (100.0%), D. grandis KS $0485^T$ (99.2%), D. roseus TDMA-$uv51^T$ (98.9%), and D. yunweiensis $YIM007^T$(100.0%), respectively. These 5 species have never been proposed in Korea; therefore 5 species of 1 genera in the family Deinococcaceae in the order Deinococcales within the class Deinococci are reported for proteobacterial species found in Korea.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.8
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• pp.764-768
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• 2002

In this paper, a double balanced gilbert cell MMIC mixer was realized in Tachyonics SiGe HBT technology. The fabricated mixer has 17 dB conversion gain, 9.8 dB noise figure, -4.2 dBm output 1 dB compression point, -27 dBc RF to IF isolation, and the good input, output matching characteristics. It draws 10 mA from a 3 V supply. The simulation and the measured results are closer to each other, which confirms accuracy of the model library and reliability of the process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.706-712
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• 1999

PSD (particle size distribution) for 2,000 mg/$\ell$ natural loess in seawater showed normal distribution cure at 0 minute settling time, accompanying with very large particle distribution range with its mean particle diameter of 31.6 $\mu$m and coencient of variance of $72.6\%$, With elapsed time it showed that the PSD was rapidly changed from normal distribution cure to abnormal distribution curve, steepened the right-hand side of it and its coefficient of variance was getting increased because of rapid settling of large size particles, Cumulative weight distribution showed that 2,000 mg/$\ell$ natural loess in seawater was almost $100\%$ constituted of particles bigger than 20 $\mu$m in diameter. Ratio of $V_s/(D_{bm})^{1/2}$ for loess particles in seawater was increased with increase of particle size in geometrical progression. Almost all loess particles in seawater had Stokes settling velocity not less than 2,255 times of Brownian diffusion coefficient, There was almost to EDL (about 0.4 nm) around natural loess particles in seawater, Thus, there was always LVDW attractive force between loess particles approaching each other in seawater, and almost no EDL repulsive force. Loess particles were not always in the condition of easy floe formation. Concentration of natural loess in seawater increasing from 400 mg/$\ell$ to 10,000 mg/$\ell$, characteristics of the settling was changed from Type I settling (discrete settling) to Type II settling (flocculation settling). PVD (particle volume distribution) showed that natural loess particles in seawater were largely constituted of two types of particles, such as rapidly settling particles and suspended and dispersed particles for a long time. Amount of the latter was much less than that of the former.

• Journal of Life Science
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• v.29 no.2
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• pp.239-247
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• 2019

The aim of this study was to improve the efficacy and functionality of Viola mandshurica (VM). A water suspension of VM power was fermented for 72 hr with Bacillus methylotrophicus CBMB205 (BM) and Leuconostoc pseudomesenteroides NRIC1777 (LP) isolated from kimchi. The antioxidant activity and reducing power of fermented VM, its total phenolic and flavonoid compounds, as well its inhibitory activity on ${\alpha}$-amylase, ${\alpha}$-glucosidase, and pancreatic lipase were determined and compared to those of non-fermented VM (NVM), a negative control. The total phenolic and flavonoid compounds of VM fermented with BM and LP were higher than those of NVM by 1.4, 1.17, and about 3 times. There was no difference in 2, 2'-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity between fermented VM and NVM. However, there was a 2.1- and 1.6-fold increase in 2, 2'-azino-bis-(3-ethylbenzothzoline-6-sulfonic acid) (ABTS) radical scavenging activity in VM fermented with BM and LP, respectively. The reducing power of BM was 1.6 times as high as NVM, but no significant difference was found between LP and NVM. Fermented VM's inhibitory activity on ${\alpha}$-amylase, ${\alpha}$-glucosidase, and pancreatic lipase was much higher than that of NVM. Fermenting VM with BM was superior to fermenting it with LP, except flavonoid content. Taken together, VM fermented with BM could be used as a functional food and as an additive to cosmetics.

• Journal of the Korean Electrochemical Society
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• v.4 no.4
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• pp.152-159
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• 2001

Electric vehicle performance is very dependent on traction batteries. For developing the electric vehicles with high performance and good reliability, the traction batteries have to be managed to get maximum performance under various operating conditions. The enhancement of the battery performance can be accomplished by implementing battery management system (BMS) that plays important roles of optimizing the control mechanism of charge and discharge of the batteries as well as monitoring battery status. In this study the battery management system has been developed for maximizing the use of Ni/MH batteries in electric vehicle. This system provides several tasks: the control of charging and discharging, overcharge and over-discharge protection, the calculation and display of state of charge, safety and thermal management. The BMS was installed in and tested using the DEV5-5 electric vehicle developed by Daewoo Motor Co. and Institute for Advanced Engineering in Korea. The 18 modules of Panasonic Ni/MH battery, 12 V-95 Ah, were used in the DEV5-5. The high accuracy within the range of $3\%$ and the good reliability were shown in the test results. The BMS can also improve the performance and cycle life of Ni/MH battery pack as well as the reliability and safety of the electric vehicles (EV).

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.394-402
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• 2013

This paper presents design, fabrication and ruggedness test of switching-mode power amplifier using GaN(Gallium Nitride) HEMT(High Electron Mobility Transistor) for S-band radar applications. The power amplifier is designed to Class-F for high efficiency. The input signal for the measurement of the power amplifier is pulse signal at $100{\mu}s$ pulse width and duty cycle of 10 %. The measurement results of the fabricated Class-F power amplifier are a power gain of 10.8 dB, an output power of 40.8 dBm, a power added efficiency(PAE) of 54.2 %, and a drain efficiency of 62.6 %, at the center frequency. We proposed reliability test set-up of a power amplifier for ruggedness test. And we measured output power and efficiency according to VSWR(Voltage Standing Wave Ratio) variation. The designed power amplifier achieved output power of 32.6~41.1 dBm and drain efficiency of 23.4~63 % by changing VSWR, respectively.

• Food Science and Preservation
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• v.24 no.8
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• pp.1158-1167
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• 2017

In this study, ${\beta}$-1,3/1,6-glucan, lactic acid bacteria, and ${\beta}$-1,3/1,6-glucan+lactic acid bacteria were tested for 10 weeks using an immunodeficient animal model infected with LP-BM5 murine AIDS virus On the immune activity. Cytokines production, plasma immunoglobulin concentration, T cell and B cell proliferation were measured. As a result, the T cell proliferative capacity which was weakened by immunization with LP-BM5 murine AIDS virus increased significantly T cell proliferative capacity compared with the red ginseng control group. B cell proliferative capacity was significantly higher than the infected control group. Increased B cell proliferation was reduced. In the cytokine production, IL-2, IL-12 and IL-15 in the Th1-type cytokine increased the secretion of IL-2, IL-12 and IL-15 compared to the infected control. The proliferative capacity of the treated group was higher than that of the mixed treatment group. TNF-${\alpha}$ was significantly decreased compared with the infected control group. The IL-4, IL-6 and IL-10 levels were significantly inhibited in the infected control group and the Th1/Th2 type cytokine expression was regulated by immunohistochemistry. IgE, IgA, and IgG levels were significantly lower in the immunoglobulin secretion assay than in the control. As a result, the immunomodulatory effect of ${\beta}$-1,3/1,6-glucan+lactic acid bacteria was confirmed by mixing with LP-BM5 murine AIDS virus-infected immunodeficient animal model.

• ETRI Journal
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• v.27 no.3
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• pp.312-318
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• 2005

Mid-span spectral inversion (MSSI) has to utilize high optical pump power, for its operation principle is based on a nonlinear optical wavelength conversion. In this paper, a low pump-power operation of MSSI-based chromatic dispersion compensation (CDC) has been achieved successfully, for the first time to our knowledge, by introducing a noise pre-reduction scheme in cascaded wavelength conversions with periodically poled $LiNbO_3$ waveguides at a relatively low operation temperature. As preliminary studies, phase-matching properties and operation-temperature dependence of the wavelength converter (WC) were characterized. The WC pumped at 1549 nm exhibited a wide conversion bandwidth of 59 nm covering the entire C-band and a conversion efficiency of -23.6 dB at 11 dBm pump power. CDC experiments were implemented with 2.5 and 10 Gb/s transmission systems over 100 km single-mode fiber. Although it is well-known that the signal distortion due to chromatic dispersion is not critical at a 2.5 Gb/s transmission, the clear recovery of eye patterns was identified. At 10 Gb/s transmission experiments, eye patterns were retrieved distinctly from seriously distorted ones, and notable improvements in bit-error rates were acquired at a low pump power of 14 dBm.