• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.11
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• pp.47-53
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• 2006

The power losses due to modulation index for multi-modulation scheme were analyzed under various transmission mode of satellite control and the necessary satellite link margin for transmission mode were proposed in this paper On the basis of the analyses for interference between the transmission signals and threshold of satellite control signal receiver, the optimal subcarrier signals were proposed for satellite range measurement methods, respectively. The subcarrier signal of 12 kHz or 14 kHz is proper for telecommand using the ESA method, and 16 kHz for telecommand signal using the GSTDN method. On the other hand, the telemetry subcarrier of 65.536 kHz is a proper in the viewpoint of receiver threshold value.

• Mass Spectrometry Letters
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• v.3 no.2
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• pp.54-57
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• 2012

Mass spectrometric analysis was carried out using multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) for the precise and accurate determination of the isotope ratios of ultratrace levels of uranium dissolved in 3% $HNO_3$. We used the certified reference material (CRM) 112-A at a trace level of 100 pg/mL for the uranium isotopic measurement. Multiple collectors were utilized for the simultaneous measurement of uranium isotopes to reduce the signal uncertainty due to variations in the ion beam intensity over time. Mass bias correction was applied to the measured U isotopes to improve the precision and accuracy. Furthermore, elemental standard solution with certified values of platinum, iridium, gold, and thallium dissolved in 3% $HNO_3$ were analyzed to investigate the formation rates of the polyatomic ions of $Ir^{40}$ $Ar^+$, $Pt^{40}$ $Ar^+$, $Tl^{40}$ $Ar^+$, $Au^{40}$ $Ar^+$ for the concentration range of 50-400 pg/mL. Those polyatomic ions have mass-to-charge ratios in the 230-245 m/z region that it would contribute to the increase of background intensity of uranium, thorium, plutonium, and americium isotopes. The effect of the polyatomic ion interference on uranium isotope measurement has been estimated.

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.85-90
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• 2006

RFID(Radio Frequency IDentification) is appearing by point technology by Ubiquitous environment of new paradigm and Logistics' application But, RFID chip of this is high price and short bandwidth, low power and interference etc. can become technological problem This is getting into obstacle in common use. Reader and tag, Embedded software etc.. that are accomplishing standardization are imported paying most expensive royalty. This paper deals with a RFID cognition system that use PDA under ubiquitous environment to apply to Logistics system A RFID cognition system processes input/output of fundamental information attaching a tag onto products. And a RFID cognition system supports quick, correct and sqfe synthetic Logistics managerial system through construction of database. This can minimize logistics costs and improve the quality of customer service. A RFID cognition system has advantage that can widen range of application to area that cognition system of existent fixing style can not do. Also, it can expect economical effect through inexpensive system construction.

• Nuclear Engineering and Technology
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• v.24 no.2
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• pp.163-167
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• 1992

Nondestructive neutron activation analysis of copper in high purity Aluminum samples which can be used as a parameter of impurity is investigated and determined. Other 23 trace impurity elements in the samples are also determined. In the analysis of copper, the new irradiation method using thermal column was applied to reduce the interfering activity of 24Na produced by 27Al(n,$\alpha$)24Na reaction induced by fast neutron. As a result, the interference can be reduced to 100 times more than other activation methods. Also the influence by activity of 24Na is found in the range of 2~3 %. It has been observed that the copper contents in so-ratted“six nine”class standard aluminum samples are about 0.54 $\pm$ 0.08 ppm. By the comparison with other values re-ported, our results are reasonable and can be available as a improved routine analysis.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.12
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• pp.1219-1224
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• 2016

The current wireless power charge technologies are based on induction coupling, magnetic resonant coupling, electromagnetic wave, etc. However, the current wireless power charge technologies has several disadvantages including short transfer range, electromagnetic interference, etc. In this paper, we investigate and demonstrate a laser wireless power charge technology. A laser source is used in the transmitter to convert from electric power to optical power and a solar cell or a photodiode is used in the receiver to convert from optical power to electric power. The laser wireless power charge technology may be the most efficient wireless power charge technology in the long distance over than 10 meters. Our experimental results show a transfer efficiency of 2.15% at the 70-m long distance with a 100 mW laser transmitter and a photodiode receiver.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.9
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• pp.929-937
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• 2008

A GPS receiver system utilized on satellite launch vehicles should operate normally under harsh environments as well as high-dynamic conditions. The GPS receiver system to use for range safety of KSLV(Korea Space Launch Vehicle)-I that is the first satellite launch vehicle developed by KARI(Korea Aerospace Research Institute) has been confirmed to survive under the environment of the launcher through extensive terrestrial tests including humidity, high and low temperatures, vacuum, sinusoidal and random vibrations, shocks, acceleration, EMI/EMC(Electromagnetic Interference/ Electromagnetic Compatibility), etc. Several performance tests have been also carried out in order to evaluate tracking capability and accuracy of the GPS receiver under high-dynamic conditions using a GPS signal simulator. Some lessons-learned during development of the GPS receiver system and its special characteristics compared with COTS(Commercial-Off-The-Shelf) GPS receiver systems are described in this paper.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.765-773
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• 2009

Edwardsiella tarda is a pathogen with a broad host range that includes human and animals. The E. tarda hemolysin (Eth) system, which comprises EthA and EthB, is a noted virulence element that is widely distributed in pathogenic isolates of E. tarda. Previous study has shown that the expression of ethB is regulated by iron, which suggests the possibility that the ferric uptake regulator (Fur) is involved in the regulation of ethB. The work presented in this report supports the previous findings and demonstrates that ethB expression was decreased under conditions when the E. tarda Fur ($Fur_{Et}$) was overproduced, and enhanced when $Fur_{Et}$ was inactivated. We also identified a second ethB regulator, EthR, which is a transcription regulator of the GntR family. EthR represses ethB expression by direct interaction with the ethB promoter region. In addition to ethB, EthR also modulates, but positively, luxS expression and AI-2 production by binding to the luxS promoter region. The expression of ethR itself is subject to negative autoregulation; interference with this regulation by overexpressing ethR during the process of infection caused (i) drastic changes in ethB and luxS expressions, (ii) vitiation in the tissue dissemination and survival ability of the bacterium, and (iii) significant attenuation of the overall bacterial virulence. These results not only provide new insights into the regulation mechanisms of the Eth hemolysin and LuxS/AI-2 quorum sensing systems but also highlight the importance of these systems in bacterial virulence.

• Analytical Science and Technology
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• v.14 no.1
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• pp.34-43
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• 2001

The present work is aimed to evaluate the conditions of the hydride generation (HG) for germanium analysis by inductively coupled plasma (ICP)-atomic emission spectrometry (AES). Twelve different kinds of acids were used such as phosphoric, hydrochloric, nitric, sulfuric, perchloric, boric, tartaric, malic, oxalic, tannic, citric, and acetic acid. It was found that phosphoric acid yielded the maximum efficiency of hydride generation. Also, efficient hydride generation was obtined with the buffer solutions containing phosphate ions over a wide range of pH. In addition, in the presence of phosphoric acid the interference caused by metals was suppressed in the hydride generation of germanium. As the concentrations of a reducing agent and a stabilizing increased the hydride generation efficiency and the acid concentration proviaing the maximum intensity were increased. By using an analytical method developed in this study, the contents of germanium in water and rock samples were determined. The detection limit of germanium in the presence of phosphoric acid was $0.03{\mu}g/L$.

• Analytical Science and Technology
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• v.7 no.2
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• pp.141-147
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• 1994

The adsorptive stripping voltammetry of corticosterone was studied in $1.0{\times}10^{-2}M$ sodium hydroxide as supporting electrolyte. The analytical conditions were as follow : 360 sec. for deposition time, -8.0 volts deposition potential, medium size mercury drop, and 20mV/sec scan rate. Calibration curve has shown a linearlity in the range of $5.0{\times}10^{-9}M$ to $8.0{\times}10^{-7}M$ and the detection limits have been $9.5{\times}10^{-10}M$ for corticoterones. This method has shown such a high sensitivity even in dilute solution that has been useful for analyzing sex hormones in medical supplies without interference of additives.

• Analytical Science and Technology
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• v.7 no.2
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• pp.133-140
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• 1994

The determination of sex hormones by adsorpive stripping voltammetry in $1.0{\times}10^{-2}M$ sodium hydroxide as supporting electrolyte has been investigated in the conditions as follows : 240sec. for deposition time, -0.80 volts deposition potential, medium size mercury drop, and 20mV/sec scan rate. Calibration curve has shown a linearlity in the range of $5.0{\times}10^{-9}M$ to $8.0{\times}10^{-7}M$ and the detection limits have been $8.0{\times}10^{-10}M$ for progesterone and $1.4{\times}10^{-9}M$ for testosterone propionate. This method has shown such a good sensitivity even in dilute solution that has been use full for analyzing sex hormones in medical supplies without interference of additives.