• Journal of Power Electronics
• /
• v.9 no.6
• /
• pp.845-853
• /
• 2009

This paper presents a novel hybrid pole BLSRM (Bearingless Switched Reluctance Motor) and its radial force control scheme. The proposed hybrid pole BLSRM has separated radial force poles and rotating torque poles. According to the FEM analysis, the proposed BLSRM has an excellent linear characteristic of radial force and controllability that is independent from the torque current. The radial force can be produced by the radial force winding which is wound at the separated radial force poles. The rotating torque is produced by the excitation current of the torque windings which are wound at the torque pole. The proposed radial force control scheme is independent of the phase torque winding current. A simple PID controller and look-up table are used to maintain a constant rotor air-gap. The proposed BLSRM and its radial force control scheme are verified by FEM analysis and experimental tests.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.2 no.1
• /
• pp.151-155
• /
• 1978

General components and detergency of commercial shampoos have been investigated and the results are summerized in the following. Shampoos were analyzed for surfactants and additives by KS method and surfactants were confirmed by T.L.C. Considerable differences in amounts of non volatiles and surfactants were found. Three of them contain either lanoline or sterols as additives and in the three. propylene glycol was found in their liquid part. It was shown that predominant sufactant was anionic and in all, except one. a little ampholytic surfactant was detected. But, contrary to forecast, in only one a little of non ionic surfactant was detected. Detergency of shampoos was examined using artificially soiled wool muslin. Considerable difference was found, and all shampoos showed higher detergency than a synthetic powder type detergent for textiles. There were no significant correlation between detergency and amount of surfactants or suspending power of detergents.

• Applied Chemistry for Engineering
• /
• v.16 no.1
• /
• pp.1-8
• /
• 2005

Electrorheological (ER) fluids, typically composed of particles having higher dielectric constant or electric conductivity than that of suspending fluids with a low viscosity, undergo dramatic, reversible changes when exposed to an external electric field. Among various electroactive materials, we put our efforts on inorganic materials including zeolite, MCM-41, MCM-41/polyaniline composite and SBA-15/polyaniline composites. Their preparation and ER characteristics are introduced.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.20 no.1
• /
• pp.65-78
• /
• 2002

The suspension polymerization of styrene was carried out to obtain the narrow-size distribution of particle by using poly(vinyl alcohol) (PVA) as suspension stabilizer according to the degree of hydrolysis and the molecular weight. The stabilizing properties of suspension are also dependent on the interfacial tension of aqueous solution when PVA is added. When the polymerization process was carried out with low hydrolyzed PVA, it gave single, well-defined particles, while high hydrolyzed PVA gave clusters. The size of particle produced in this study ranged between 5${\mu}{\textrm}{m}$ and 10${\mu}{\textrm}{m}$. The suspending agent, PVA, influences on the drop size and drop stability, When the molecular weight of PVA is increased, the drop size decreases and the drops become more stable toward coalescence. An increase in the PVA concentration decreases the mean drop size and narrows the drop size distribution.

• Applied Biological Chemistry
• /
• v.20 no.2
• /
• pp.175-181
• /
• 1977

Lysosomal enzyme latency was demonstrated for hydrolases from porcine leukocyte by suspending sediment sfrom differential centrifugation in 0.125 to 0.250 M sucrose. Specific activities pH optima and activation energies were determined for hydrolases distributed in various sedimentation fractions and for enzymes solubilized by n-butyl alcohol extraction. Specific activities of the hydrolases revealed the heterogeneity of the Iysosomal fractions relative to enzyme content. pH optima identified the enzyme as acid hydrolases with optima for cathepsin D and aryl sulfatase also at pH 6.8. Activation energies of some hydrolases were low revealing that these enzymes could function efficiently during low temperature aging of meat.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.2 no.1
• /
• pp.61-72
• /
• 1999

A Technical Manual is the tool that offers a guidance to a maintenance engineer in order to exactly use and maintain of complicated weapon system. Because the modern weapon system are complex and functionality integrated, its quantity is massive. So We spend a lot of money on its publication and suspending recent information. To solve this problem, to reduce a risk of loss and use easily, this study develops the IETM(Interactive Electronic technical manual) which observes the CALS standard. This paper provide the development concept, environment, technic of IETM.

• Proceedings of the KIPE Conference
• /
• 2008.06a
• /
• pp.268-270
• /
• 2008

Bearingless switched reluctance motors (SRM) have combined advantages of conventional SRM and magnetic bearings. Therefore in this paper based on novel structure of Bearingless SRM, an accurate mathematic model of radial force is deduced. Meanwhile in order to realize steady suspending, a novel radial force control method- Direct Instantaneous Radial Force Control (DIRFC) is presented. The effectiveness of new model and DIRFC is proved by the simulation results.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.528-530
• /
• 2003

We present a novel photo-addressable electronic paper using an electrophoretic device, which can show and sustain the 2D images transferred by the UV illumination. The device consists of the organic photoconducting layer reacting with the UV illumination and the electronic ink (white particles and blue dye) dispersing in a suspending medium. The voltage impression under illuminating of UV make an image be transferred to the electrophoretic cell. The transferred image can be maintained by the bistability of the electrophoretic device.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2003.07a
• /
• pp.995-997
• /
• 2003

In this study, we have investigated the positively charged polymer particles using emulsifier-free emulsion polymerization for applications in electrophoretic displays. The FT-IR, Zeta potential and SEM characteristics showed that by emulsifier-free polymerization, the positively charged polymer particles were manufactured. Using these particles, we can obtain well-dispersed white latex particles in dielectric suspending media.

• Journal of the Korean Ceramic Society
• /
• v.28 no.2
• /
• pp.146-152
• /
• 1991

Ultra fine and homogeneous (Ni0.4Zn0.6)Fe2O4 ferrite powders were prepared by direct-wet, Hydrothermal and coprecipitation methods. In case that specific surface areas of Ni-Zn ferrite powders were over 220㎡/g, 100㎡/g, 30㎡/g individually direct-wet, hydrothermal and coprecipitation methods. The Ni-Zn ferrite magnetic fluids of which Solvents were benzene or kerosene was prepared by making cation surfactant adsorbed on the surface of the (Ni0.4Zn0.6)Fe2O4. The results that measured dispersion and viscosity by making cation surfactant adsorbed were as follows. 1. The adsorption amount of Oleric acid be proportioned the specific surface area of powders. 2. The maximum amount of Oleric acid was 36wt% of dried powders which has 220㎡/g of specific surface area. 3. The stability of fluid by direct-wet synthesis emthod in benzene or kerosene solvent excellent.