• Journal of Korean Society of Water and Wastewater
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• v.28 no.2
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• pp.181-193
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• 2014

Various treatment system for residuals have applied to save water resources, but most of them were not be satisfied with legal standard consistently. In this study, submerged membrane treatment system was operated to treat water treatment plant residuals and operation parameters was evaluated. Result of this experiment, high concentration organic matters contributed to high increase Transmembrane pressure(TMP) of membrane system(from 0.05 bar to 0.35 bar). And backwash process was effective to stabilize membrane system operation. After Cleaning-In-Place(CIP), permeability was recovered about 100 % from first operation condition. Inorganic matters (Fe, Mn, Al, Ca, Mg) were not effective membrane filtration performance. The quality of residual treatment was satisfied with drinking water quality standard and a treated water from that system was suitable for water reuse.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.10
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• pp.1110-1118
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• 2012

In this study, for reducing the residual vibration in high speed motion control stage, an improved 5th order polynomial motion profile was developed. When a stage is moving, the current through the motor coils has the same profile of input motion profile of acceleration, therefore the characteristics of the acceleration input profile directly affect on the performance of the amplifier that includes the current control loop. Commonly low cost amplifier and motor has a narrow current control bandwidth, therefore the proposed algorithm was designed based on this practical constraint. Simulation and experimental results showed that the proposed algorithm clearly has low residual vibration characteristics than conventional 5th order polynomial motion profile on the same drive condition.

• Structural Engineering and Mechanics
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• v.45 no.4
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• pp.471-494
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• 2013

In this paper, identification of isotropic and orthotropic linear elastic material constitutive parameters has been demonstrated by a FEA-free energy-based inverse analysis method. An important feature of the proposed method is that it requires no finite element (FE) simulation of the tested material. Full-field displacements calculated using digital image correlation (DIC) are used to compute DIC stress fields enforcing the equilibrium condition and DIC strain fields using interpolation functions. Boundary tractions and displacements are implicitly recast into an objective function that measures the energy residual of external work and internal elastic strain energy. The energy conservation principle states that the residual should be zero, and so minimizing this objective function inversely identifies the constitutive parameters. Synthetic data from simulated testing of isotropic materials and orthotropic composite materials under 2D plane stress conditions are used for verification of the proposed method. When identifying the constitutive parameters, it is beneficial to apply loadings in multiple directions, and in ways that create non-uniform stress distributions. The sensitivity of the parameter identification method to noise in both the measured full-field DIC displacements and loadings has been investigated.

• International Journal of Naval Architecture and Ocean Engineering
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• v.8 no.6
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• pp.563-576
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• 2016

The flight deck of an aircraft carrier is relatively vulnerable compared to its hull, as the damage of some subsystems on the flight deck may cause the carrier losing its operational capability. Therefore, this work aims to represent a simulative method for evaluating the resistance of the flight deck's operational capability in the condition that the aircraft carrier is together with its strike group and the enemy uses the anti-ship missiles with the cluster warheads to attack. In the simulations, the susceptibility of the carrier and the vulnerability of the aircraft guarantee resources are gained. Then, with the help of the closed queuing network, the residual sortie generation rate can be solved, which reflects the flight deck's residual operational capability. The results have proven that the flight deck is of strong resistance to these attacks while it is very sensitive to the loss of some key aircraft guarantee resources.

• Journal of Environmental Science International
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• v.14 no.2
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• pp.193-199
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• 2005

To obtain the residual organochlorine pesticides in the ginseng, the methods of multi-analysis for BHC's isomer, DDT's isomer and other organochlorine pesticides by GC-ECD are surveyed. The relative retention time for $\alpha-BHC,\;\beta-BHC,\;\delta-BHC\;and\;\gamma-BHC$ is 1.000, 1.025, 1.034 and 1.056, respectively. The relative retention time for o,p-DDE, p,p-DDE, o,o-DDD, o,p-DDT, o,p-DDD, and p,p-DDT is 1.199, 1.230, 1.242, 1.286, 1.329 and 1.333, respectively. The BHC isomers, DDT's isomer and other organochlorine pesticides are separated with multianalysis condition. The qualified defection concentration for $\alpha-BHC$, Quintozene, Aldrin, Captan, $\alpha-Endosulfan$, and Dieldrin is 0.95ng/g, 0.27ng/g, 1.04ng/g, 0.63ng/g, 0.55ng/g and 0.62ng/g, respectively. The qualified defection concentration for Fenhexamid, Endrin, $\beta-Endosulfan$, o,p-DDT, Endosulfan-sulfate is 5.71ng/g, 0.61ng/g, 0.48ng/g, 0.44ng/g and 0.51ng/g, respectively. BHC, Aldrin, Dieldrin, Endrin and DDT, which were Korea Food & Drug Administration advisory pesticides, are not detected in soil environment. Also it's residual organochlorine pesticides are not polluted in the ginseng on Sangju Korea.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.918-921
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• 2001

In grinding process, the heat of $1200^{\circ}$~$1500^{\circ}$ on the grinding area between grinding wheel and workpiece is generated. It decreases the surface integrity of workpiece and causes the thermal damages such as the deformed layer, residual stress and grinding burn. Generally coolant is widely used for preventing the heat generation on the grinding area, but it deteriorates the working condition by polluting the atmosphere of workplace and in the end pollutes the environment. The grinding methods using the compressed cold air and mist are the cooling methods to substitute conventional coolant. They can decrease the environmental pollution through not using coolant any more or minimizing it. In this study, the cooling effects of grinding methods using the compressed cold air and mist have been investigated. The grinding system equipped with the water bathe and mist spray nozzle was developed. The energy partition to workpiece through measuring the temperature on the workpiece surface was calculated. The surface integrity of workpiece and thermal damage like the deformed layer were analyzed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.10
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• pp.1571-1579
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• 1997

The development of a new material which should be continuously use under severe environment of very high temperature has been urgently requested. For the development of such super-heat resistant materials, the main problem is not only to make the superior thermal barrier properties but also to actively release thermal stress. So, a new concept of functionally graded material(FGM) has been proposed to overcome this problem. A composition and microstructure of FGM are varied continuously from place to place in ways designed to provide it with the maximum function of mitigating the induced thermal stress. So, FGM can be applied in the aerospace, the electronic and the medical field, etc.. In this study, thermal stress analysis of sintering PSZ/NiCrAlY graded material was conducted theoretically using a finite-element program. The temperature condition was sintering temperature assuming a cooling-down process up to room temperature. Fracture damage mechanism was anlayzed by the parameters of residual stress. It could be known that FGM provided with the function of mitigating the induced thermal stress.

• Nuclear Engineering and Technology
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• v.47 no.4
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• pp.434-442
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• 2015

The advanced passive pressurized water reactor (PWR) is being constructed in China and the passive residual heat removal (PRHR) system was designed to remove the decay heat. During accident scenarios with increase of heat removal from the primary coolant system, the actuation of the PRHR will enhance the cooldown of the primary coolant system. There is a risk of power excursion during the cooldown of the primary coolant system. Therefore, it is necessary to analyze the thermal hydraulic behavior of the reactor coolant system (RCS) at this condition. The advanced passive PWR model, including major components in the RCS, is built by SCDAP/RELAP5 code. The thermal hydraulic behavior of the core is studied for two typical accident sequences with PRHR actuation to investigate the core cooling capability with conservative assumptions, a main steam line break (MSLB) event and inadvertent opening of a steam generator (SG) safety valve event. The results show that the core is ultimately shut down by the boric acid solution delivered by Core Makeup Tank (CMT) injections. The effects of CMT boric acid concentration and the activation delay time on accident consequences are analyzed for MSLB, which shows that there is no consequential damage to the fuel or reactor coolant system in the selected conditions.

• Microbiology and Biotechnology Letters
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• v.23 no.3
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• pp.346-351
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• 1995

To produce ethanol from Jerusalem artichoke powder efficiently, Kluyveromyces marxianus F043 cells were encapsulated in 2% sodium alginate and were cultured in a countinuous reactor to investigate the fermentation properties. Immobilized K. marxianus F043 cells were activated for 48 hours in a fermentor for continuous ethanol production. The culture in a CSTR using a Jerusalem artichoke substrate treated with 2% cellulase showed a decrease in ethanol concentration and an increase in residual saccharide concentration with a increasing dilution rate. Optimum conditions for high ethanol productivity and low residual saccharide output were clarified to be given at a dilution rate of 0.2 h$^{-1}$ and a Jerusalem artichoke medium concentration of 75 g/l. Ethanol productivity of 3.1 g/l-h and saccharide utilization of 62.6% were obtained under the optimum condition. When the fermentation was performed for 3 weeks under these conditions, the effluent medium showed stable ethanol concentrations of 16.3 - 17.9 g/l and viable cells of 6.60-7.16 log cells/ml without contamination. Trace amounts of methyl, n-propyl, iso-butyl, isoamyl alcohols besides ethanol were detected.

• 전기의세계
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• v.21 no.6
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• pp.17-20
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• 1972

The magnetic properties of Ba-Ferrite ( $M^{+2}$O.nF $e_{2}$ $O_{3}$ is highly improved under the condition of composition ratio n=4.4 when B $i_{2}$ $O_{3}$ is added to Ferrite, the adding amount and sintering temperature which affect the magnetic properties were investigated and the following results; were obtained; 1. Magnetic properties are varied with B $i_{2}$ $O_{3}$ content and singering temperature, and coercive force and residual induction can be improved with B $i_{2}$ $O_{3}$. 2. The optimal content of B $i_{2}$ $O_{3}$ amount is about 4 mol %, 3. Without the addition of B $i_{2}$ $O_{3}$, the optimal sintering temperature is about 1300.deg. C, but when 4 mol % of B $i_{2}$ $O_{3}$ is added, the optimal sintering temperature falls to the range of 900.deg. C to 1100.deg. C and it also improves magnetic properties. 4. Residual induction increases as the singering temperature is raised to 1100.deg. C. Coercive force also increased as the sintering temperature is raised to 1000.deg. C, but it rapidly decreases when sintering temperature goes beyond 1000.deg. C. 5. Only a negligible change may be noticed in the decrease of Curie temperature by the addition of about 4 mol % of B $i_{2}$ $O_{3}$.