• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.645-650
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• 2006

The heat transfer performance and energy transport ability are relatively high due to higher specific heat. Therefore, it can be used in fields such as heating, ventilating, air-conditioning, refrigeration and heat exchangers. In this study, liquid-cooling heat exchangers were designed and tested by varying geometry and operating conditions. In addition, liquid-cooling heat exchangers were tested to provide performance data for MPCM slurry. The liquid-cooling heat exchangers had twelve rectangular channels with flow paths of 1, 2, 4 and 12. Silicon rubber heaters were used to control the heat load to the heat exchanger. Heat input ranged from 293 to 800 W, and inlet temperatures of working fluid varied from 15S to $27^{\circ}C$. The standard deviation of surface temperature was strongly affected by the coolant of MPCM Slurry, All MPCM-cooling heat exchangers showed higher cooling performance than the water-cooling heat exchanger except one path channel heat exchanger.

• Membrane Journal
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• v.24 no.2
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• pp.142-150
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• 2014

This paper is to develop the process suitable for the advanced treatment of liquid fertilizer from the livestock night soil treatment facility (biogas plant). Nanofiltration (NF) and reverse osmosis (RO) process was used, respectively, for the advanced treatment of liquid fertilizer. And membrane bioreactor (MBR) with and without biomedia were tested, respectively, for the pretreatment. It was found that almost T-N of the liquid fertilizer was composed of ammoniacal nitrogen. Transmembrane pressure of MBR with biomedia increased slowly during the operation time, while that of MBR without biomedia increased rapidly at the initial time. But there was no difference observed in the removal efficiencies of COD, T-N, and T-P irrespective of the dosage of biomedia. When the liquid fertilizer was pretreated by MBR with biomedia, the removal efficiencies of COD, T-N, and T-P were 99.8, 86.5%, and 99.8% by NF, and 99.9, 86.8%, and 99.8% by RO, respectively. Compared with the effluent quality standards of the livestock night soil treatment facility, the water quality treated by MBR and NF/RO process met the standard for COD and T-P, but exceeded the permitted standard for T-N. In order to meet the effluent quality standard for T-N, it is necessary to change the MBR operation cycle or to add the secondary treatment by NF/RO.

• Journal of computational fluids engineering
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• v.8 no.3
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• pp.12-20
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• 2003

A numerical procedure for the calculation of solidification and melting phase change using PISO algorithm is presented. In case of phase change problem, the coupling between velocity/pressure/temperature and liquid fraction is important. The converged temperature and liquid fraction solution which satisfies the energy balance is acquired by applying enthalpy method into inner iteration in matrix solver. And a modified PISO algorithm version is introduced to properly solve the coupling between velocity/pressure/temperature and liquid fraction. A comparison of the proposed procedure with a standard iterative method shows improvement both in terms of computing speed and robustness.

• Korean Journal of Human Ecology
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• v.22 no.1
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• pp.17-27
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• 2013

The purpose of this study is to investigate children's liquid conservation concept according to their ages and task-situations in the water evaporation phenomenon. Thirty from each 4-, 6- and 8-year-old age groups (total of 90 subjects) were selected for this study. The subjects were recruited from two day-care centers, a kindergarten, and an elementary school, in Seoul. Statistical methods used for data analysis were frequencies, percentiles, means, standard deviations and repeated measures ANOVA. As a result, there was a significant difference in children's liquid conservation concept in the evaporation of water according to their ages and task-situations. 8-year-old children showed levels of cognition than 4- and 6-year-olds. Children showed higher levels of cognition in the task of drying than in the task of water level changes.

• Analytical Science and Technology
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• v.8 no.4
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• pp.457-460
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• 1995

A new hollow fiber filled with the lower refractive index liquid as core constructs a liquid core optical fiber(LCOF). The LCOF have been used as colorimetric cell to determine elements Cr and Cu in the presence of 70%- 50% ethanol or 50% dioxane aqueous solution, based on colored complex of Chromium(VI) with Diphenycarbazid(DPC) and copper with Chromaurd S(CAS) respectively. The sensitivity (1/ng/ml) of calibration curve of Cr and Cu are 0.052, 0.017 over the range 0 - 25, 0 - 24(ng/ml) respectively. The Cr in the animal gum and Nation Standard of China are determined with recoveries of 94 - 102%.

• Structural Engineering and Mechanics
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• v.53 no.6
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• pp.1127-1141
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• 2015

The optimum design of liquid column dampers in seismic vibration control considering system parameter uncertainty is usually performed by minimizing the unconditional response of a structure without any consideration to the variation of damper performance due to uncertainty. However, the system so designed may be sensitive to the variations of input system parameters due to uncertainty. The present study is concerned with robust design optimization (RDO) of liquid column vibration absorber (LCVA) considering random system parameters characterizing the primary structure and ground motion model. The RDO is obtained by minimizing the weighted sum of the mean value of the root mean square displacement of the primary structure as well as its standard deviation. A numerical study elucidates the importance of the RDO procedure for design of LCVA system by comparing the RDO results with the results obtained by the conventional stochastic structural optimization procedure and the unconditional response based optimization.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3190-3194
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• 2010

Mixed electrolytes formed by the combination of 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (BMP-TFSI) ionic liquid and standard liquid electrolyte are prepared and characterized. Linear sweep voltammetry measurements demonstrate that these mixed systems exhibit a wide electrochemical stability window, allowing them to be suitable electrolyte for carbonaceous anode-based lithium-ion batteries. Lithium-ion cells composed of graphite anode and $LiCoO_2$ cathode are assembled using the mixed electrolytes, and their cycling performances are evaluated. The cell containing proper content of BMP-TFSI shows good cycling performance comparable to that of a cell assembled with organic electrolyte. The presence of BMP-TFSI in the mixed electrolyte contributes to the reduction of the flammability of electrolyte solution and the improvement of the thermal stability of charged $Li_{1-x}CoO_2$ in the electrolyte solution.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.195-198
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• 2001

We developed the portable blood analysis system, which can be measured pH of the blood. This system is composed to electronic circuit, mechanism, and system software. Electronic circuit is composed to the sensor, pre-amp part, temperature regulation part, fluid sensing part, A/D(analog to digital) conversion part, main and peripheral device processing part. And the mechanism is composed to the flow cell and the liquid flow part. The liquid flow part is consisted of blood and washing control system under the control of the 6-channel solenoid valve and syringe rump. The system software is composed to measurement program, calibration program, washing and diagnostic program. The program of each routine is designed as sequential process for an efficiency. And the portable pH analysis system used two-point calibration method using the two types of corrective liquid. As a result, we obtained the calibration curve and calculated the value of pH. For verifying the system, we confirmed the output voltage of the sensor, and estimated reappearance of system using the standard liquid.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.4
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• pp.3153-3159
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• 1973

Although standard method of test for liquid limit procedure is issued under the fixed designation KSF-2303 in 1968, for both of general method and on point method, the latter of which is not still favorably used among laboratory engineers with its defficiency of adquate informations. This study intended as to furnish proper information to the laboratory engineers for the use of one point liquid limit test with full advantages of time-saving and labor-saving. further more, the following conversion formula to the one point method VS. general method is presented by the results of analytical study on 1017 Soil sampls existing liquid limit test data The formula is; $$W_L = W(\frac{N}{25})^{0.118}$$ The conversion factor (table-4) is also attached for the convenience of the users.

• Journal of the Korean Institute of Telematics and Electronics
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• v.23 no.1
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• pp.46-49
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• 1986

A 32x32 liquid crystal (LC) flat panel display using two-dimensional array of PMOS switches and capacitors is designed and fabricated. Standard PMOS process was followed to fabricate the switch and capacitor array on silicon wafer, on the top of which guest-host effect liquid crystal was wmployed as an electro-optical material for optical switching and liquid crystal display(LCD) with its external drive circuitry was basically successful. Remaining problems to be solved are improvement of contrast ratio, good surface alignment and uniformity.