• Tribology and Lubricants
• /
• v.11 no.1
• /
• pp.50-57
• /
• 1995

When engine oil is used under severe running condition, the Lubricational characteristics is very important. I have studied the Lubricational characteristics with Compound Additives of engine oil for the Falex wear test machine. Adding detergent (Ca-phenate) to engine oil, the seizure is more improved than in case of non-adding, and adding Zn-DTP (Zinc dialkyl dithio phosphate), the extreme pressure property is excellent at the high load. But when the PTFE (Polytetra Fluoro Ethylene) and MoS$_{2}$ (Molybdenum disulfide) are added, the temperature characteristics and the anti-wear property become excellent because the stability can be maintained in a high temperature. The result are as follows, it can be improved that when the compound of the Ca-phenate and Zn-DTP, MoS$_{2}$, PTFE, etc. was added to engine oil, the lubrication characteristics become better. It is argued that it is improved because of excellence of the anti-wear, the extreame pressure properties and the heat stability.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.09a
• /
• pp.76-79
• /
• 2004

This research was carried out to evaluate role of supplementary reagents, such as phosphate and SDS, to remove hydrophobic organic contaminant from soils during the EK-Fenton process. The $H_2O$$_2$ stability improved due to the role as stabilizer of phosphate and SDS during the EK-Fenton process. Furthermore, although pH in region near cathode was 8.2 after test, $H_2O$$_2$ stability improved due to transportation of SDS in the region near cathode. Therefore, in tests using phosphate and SDS as supplementary reagent, the efficiency of phenanthrene treatment improved through the EK-Fenton process using longer reaction time.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.5
• /
• pp.794-803
• /
• 2016

This paper propose a sensorless control system of IPMSM with a adaptive back-EMF estimator and improved instantaneous reactive power compensator. A saliency-based back-EMF is estimated by using the adaptive algorithm. The estimated back-EMF is inputted to the phase locked loop(PLL) and the improved instantaneous reactive power(IRP) compensator for estimating the position/speed of the rotor and compensating the error components between the estimated and the actual position, respectively. The stability of the proposed system is achieved through Popov's hyper stability criteria. The validity of proposed algorithm is verified by the simulations and experiments.

• Journal of Ocean Engineering and Technology
• /
• v.18 no.6 s.61
• /
• pp.51-57
• /
• 2004

In this study, the improved three-dimensional analysis model designed for a more accurate analysis of marine cable-supported structures, is presented. In this improved analysis model, the beam elements, of which the stability function is derived using Taylor's series expansions, are used to model space frame structures, and the truss elements. The equivalent elastic modulus of the truss elements is evaluated on the assumption that the deflection curve of a cable has a catenary function. By using the proposed three-dimensional analysis model, nonlinear static analysis is carried out for some cable-supported structures. The results are compared with previous studies and show good agreement with their findings.

• Journal of People, Plants, and Environment
• /
• v.22 no.4
• /
• pp.365-373
• /
• 2019

This study was conducted to determine the effects of horticultural therapy on self-esteem of women with hearing impairment. Ten women with hearing impairment registered in the Mokpo Branch of the Korean Association of the Deaf participated in the horticultural therapy programs (HTP) for self-esteem. The self-esteem scale was used to evaluate the effects of the programs and scores were compared to determine the difference before and after the programs. Self-esteem was improved in all 10 subjects, and its mean value increased with statistical significance from 22.5 points before the programs to 29.8 points after the programs. The programs preferred by women with hearing impairment included 'making a centerpiece using scented candles and flowers', 'packing and planting pot spray chrysanthemum', 'making a topiary', 'planting Hedera helix', and 'planting cyclamen'. Therefore, it was suggested that self-esteem of women with hearing impairment were improved by increasing social and family support, emotional stability, positive feedback, and self-expression through horticultural therapy programs.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.9
• /
• pp.2114-2116
• /
• 2009

• Proceedings of the KIPE Conference
• /
• 2001.10a
• /
• pp.208-211
• /
• 2001

This paper proposes a novel flyback topology and its control scheme, where some disadvantages of the conventional one are eliminated while the circuit simplicity is maintained, and furthermore confirms the improvement of its dynamic response and stability analytically and experimentally.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.13 no.1
• /
• pp.166-173
• /
• 2005

A vehicle stability control logic for 4WD hybrid electric vehicle is proposed using the regenerative braking of the rear motor and electronic brake force distribution module. Performance of the stability control logic is evaluated for J-turn and single lane change. It is found from the simulation results that the regenerative braking at rear motor is able to provide improved stability compared with the vehicle performance without my stability control. Additional improvement can be achieved by applying the regenerative braking plus electronic brake farce distribution control. It is expected that the regenerative braking offers additional improvement of the fuel economy as well as the vehicle stability control.

• Journal of Microbiology and Biotechnology
• /
• v.27 no.4
• /
• pp.718-724
• /
• 2017

The combination of rabies immunoglobulin (RIG) with a vaccine is currently effective against rabies infections, but improvements are needed. Genetic engineering antibody technology is an attractive approach for developing novel antibodies to replace RIG. In our previous study, a single-chain variable fragment, scFv57R, against rabies virus glycoprotein was constructed. However, its inherent weak stability and short half-life compared with the parent RIG may limit its diagnostic and therapeutic application. Therefore, an acidic tail of synuclein (ATS) derived from the C-terminal acidic tail of human alpha-synuclein protein was fused to the C-terminus of scFv57R in order to help it resist adverse stress and improve the stability and half-life. The tail showed no apparent effect on the preparation procedure and affinity of the protein, nor did it change the neutralizing potency in vitro. In the ELISA test of molecular stability, the ATS fusion form of the protein, scFv57R-ATS, showed an increase in thermal stability and longer half-life in serum than scFv57R. The protection against fatal rabies virus challenge improved after fusing the tail to the scFv, which may be attributed to the improved stability. Thus, the ATS fusion approach presented here is easily implemented and can be used as a new strategy to improve the stability and half-life of engineered antibody proteins for practical applications.

• KSBB Journal
• /
• v.23 no.4
• /
• pp.340-344
• /
• 2008

Coprinus cinereus peroxidase (CiP) was often used as a catalyst for oxidative polymerization of a variety of phenol derivatives to produce a new class of polyphenols. Economical point of view, to know the mechanism of enzyme deactivation is significantly important because cost of enzyme is critically high. Hydrogen peroxide being used as oxidizing agent induced deactivation of peroxidase by destruction of heme structure. In the presence of hydrogen peroxide the stability of peroxidase was unexpectedly improved by adding organic solvent. Especially 2-propanol significantly improved enzyme stability among tested solvents. Radical scavenging by organic solvents may play a major role in protecting peroxidase from the oxidation of oxidizing radicals.