• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.835-836
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• 2011

• Journal of Korean Society of Water and Wastewater
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• v.29 no.1
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• pp.1-9
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• 2015

A combined treatment system using multiple source water is becoming important as an alternative to conventional water supply for small-scale water systems. In this research, combined water treatment systems were investigated for simultaneous use of multi-source water including rainwater, ground water, river water, and reclaimed wastewater. A laboratory-scale system was developed to systematically compare various combinations of water treatment processes, including sand filtration, microfiltration (MF), granular activated carbon (GAC), and nanofiltration (NF). Results showed that the efficiency of combined water treatment systems was affected by the quality of feed waters. In addition, a simply approach based on the concept of linear combination was suggested to support a decision-making for the optimum water treatment systems with the consideration of final water quality.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.40.3-41
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• 2015

We performed simultaneous observations of H2O and SiO masers toward VX Sgr using the Korean VLBI Network (KVN) and Source Frequency Phase Referencing (SFPR) method. The observations were carried out at 5 epochs from 2014 February to 2015 June. The relative locations of the SiO with respect to the H2O maser emission were determined at two epochs by SFPR for the first time. The H2O masers show well developed asymmetric outflow features which are spread up to ~300 mas in diameter. On the other hand, the SiO masers show a ring-like structure close to the central star with ~ 30 mas diameter. The SFPR observational results at two epochs (${\varphi}=0.83$ and 0.99) provide similar relative locations of H2O and SiO maser features. These superposed maps of H2O and SiO masers lead us to investigate the development of outflow motions from relatively spherical SiO maser regions close to central star to aspherical H2O maser regions according to optical phase of stellar pulsation together with the prediction of the position of central star.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.12
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• pp.5943-5962
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• 2017

A resource allocation algorithm based on simultaneous wireless information and power transfer (SWIPT) to maximize the system throughput is proposed in orthogonal frequency division multiplexing (OFDM) relay networks. The algorithm formulates the problem under the peak power constraints of the source and each subcarrier (SC), and the energy causality constraint of the relay. With the given SC allocation of the source, we give and prove the optimal propositions of the formulated problem. Then, the formulated problem could be decomposed into two separate throughput maximization sub-problems by setting the total power to transfer energy. Finally, several SC allocation schemes are proposed, which are energy priority scheme, information priority scheme, balanced allocation scheme and exhaustive scheme. The simulation results reveal that the energy priority scheme can significantly reduce computational complexity and achieve approximate performance with the exhaustive scheme.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.5 s.347
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• pp.1-6
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• 2006

By comparing video-overlay method where digital and SCM signal are modulated in different optical source, we experimentally investigated the performance of simultaneous modulation of data and broadcasting signals using a single LD for broadcasting in PON based optical access network. The experimental results show that by increasing the minimum value of injected current for LD modulation above about 1.5 times of threshold current of LD, data and broadcasting signals can modulate without mutual interference. We also proposed and demonstrated the scheme of optical transmitter optimized for simultaneous modulation of data and broadcasting signals where anode and cathode of LD are separately used as signal interface for data and broadcasting signals, respectively.

• Natural Product Sciences
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• v.24 no.3
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• pp.206-212
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• 2018

Xanthii Fructus has been traditionally used for the treatment of rhinitis, rheumatoid arthritis, and eczema. In this study, a high-performance liquid chromatography-photodiode array (HPLC-PDA) method was developed and then used for the simultaneous analysis of eight phenylpropanoids in Xanthii Fructus. The analytical column used for this separation was a $SunFire^{TM}$ $C_{18}$ column, maintained at $40^{\circ}C$. The mobile phase used was 1.0% acetic acid in distilled water and 1.0% acetic acid in acetonitrile with gradient elution. For identify of each component, the mass spectrometer (MS) was used a Waters triple quadrupole mass spectrometer requipped with electrospray ionization (ESI) source. The HPLC-PDA method showed good linearity: correlation coefficients were ${\geq}0.9996$. The limits of detection and quantification of the eight compounds were 0.02 - 0.04 and $0.06-0.14{\mu}g/mL$, respectively. The extraction recoveries ranged from 97.51 to 108.67%. The relative standard deviation values of intra- and inter-day precision were 0.06 - 1.55 and 0.09 - 1.68%, respectively. The validated HPLC-PDA method was applied to simultaneously analyse the amounts of eight phenlypropanoids in Xanthii Fructus.

• Journal of the Korean Society of Safety
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• v.33 no.3
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• pp.21-26
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• 2018

Approximately 20% of the total fire is electrical fire, and electrical energy is a potential source of heat. Large-scale fault currents that occur during a line ground fault flow into electric utility poles, electric power equipment, or electric appliances of the customer, and cause simultaneous electrical fire. In this paper, we investigated the possibility of fire through the change of fault current flowing in faulty and sound feeder in case of 1 line ground fault in 22.9 kV distribution line. We propose a fire investigation analysis method for simultaneous multiple electrical fire such as evidence analysis method, and fault current occurrence confirmation method in case of fire accident by analyzing the fault current occurring in the ground fault in the distribution line using EMTP, electric power system analysis program.

• Progress in Superconductivity
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• v.5 no.2
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• pp.128-131
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• 2004

The resistive superconducting fault current limiters (SFCLs) are very attractive devices for the electric power network. But they have some serious problems when the YBCO thin films were used for the current limiting materials due to the in homogeneities caused by manufacturing process. When the YBCO films have some inhomogeneities, simultaneous quenches are difficult to achieve when the fault current limiting units are connected in series for increasing operating voltage ratings. Magnetic field application is one of the prospective way of inducing simultaneous quenches far the series-connected resistive FCL components. Magnetic field was typically generated by the fault current thorough a coil, which is connected to components of the fault current limiter in series, leaving the problem, which provides significant inductance to the power line and suppresses critical current density of the superconducting components. In this article we investigated the possible application of the protective current transformer (p-CT), which is available current source to the magnetic coil. This system inductively coupled to the circuit, therefore, remarkably reducing impedance to the circuit. The current by the protective current transformer was directly fed to the coil, generating magnetic field large enough to reduce critical current density of the components. This successfully induced simultaneous quenches of the series-connected resistive FCL components.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.1
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• pp.44-48
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• 2002

In this paper, we demonstrated the simultaneous measurment of triple parameters such as strain, temperature, and vibration using single FBG/EFPI hybrid sensor. The FBG/EFPI sensor system for the strain and temperature measurement and the EFPI sensor system for the the vibration measurement were combined by a wavelength division multiplexer. The optical source of FBG/ EFPI sensor system is a wavelength-swept fiber laser(WSFL) and that of an EFPI sensor system is a laser diode. We performed the simultaneous measurement of thermal strain, temperature, and vibration of a aluminum beam placed in a thermal chamber and validated the efficiency of the constructed measurment system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.181-184
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• 2003

We investigated the effect of ethanol on the production of cellulose and acetic acid fermentation by Gluconacetobacter persimmonensis KJ145. Results showed that bacterial cellulose productivity was highest when 2% ethyl alcohol was added to apple-juice medium. For acetic acid production, 7% ethyl alcohol was needed. Optimal concentration of ethyl alcohol was 5% for simultaneous production of bacterial cellulose and acetic acid. For simultaneous production of bacterial cellulose and acetic acid, optimal nitrogen source and optimal concentration were corn steep liquor and 15% (w/v), respectively Optimal culture time for simultaneous production of bacterial cellulose and acetic acid was 14 days. At the optimal condition, Cluconacetobacter persimmonenis KJ145 produced 7.55 g/L of bacterial cellulose (dry weight).