• Textile Coloration and Finishing
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• v.16 no.1
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• pp.18-25
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• 2004

In this study, the effect of microwave which can increase temperature rapidly on polyester alkaline dyeing was investigated. The final K/S values of polyester fabrics dyed by microwave lower than those of atmospheric dyeing because of the evaporation loss of dyeing solution. If the dyeing time makes longer as much as that in atmospheric dyeing, the K/S values of polyester fabrics dyed under microwave were similar to those of atmospheric dyeing. The K/S values of polyester fabrics dyed in pH 9.5 were higher than those in pH 5.5 in case of aliphatic carriers. The K/S values of organic reagent pretreated polyester fabrics dyed by use of aromatic carriers were not higher than those of non-treated polyester fabrics. But the K/S values of polyester fabrics dyed by use of aliphatic carriers were higher than those of non-treated polyester fabrics. The tensile strength were decreased with increasing of dyebath pH because the polyester fabrics were easily decomposed by high alkali.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.02a
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• pp.266-268
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• 2003

The neon liquefier by using GM cryocooler is designed and in process of manufacturing for the cooling of 100 hp high temperature superconductor (HTS) motor. It was used the principle of thermosyphon that the rotor of the motor is cooled by the latent heat of liquidized neon. The cold-box was designed to minimize heat loss by conduction, convection, radiation. Two heat exchanger were made to liquefy neon by the direct contact of neon gas on the cold head. As a first stage of our project, evaporation apparatus will be setup in the inner field of the cold-box and then the performance of neon liquefier will be test.

• Proceedings of the Membrane Society of Korea Conference
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• 1991.04a
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• pp.10-12
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• 1991

The first membrane technology applied in the Japanese industry was a. electro-dialysis(ED) process using ion-exchange meabranes. These membranes were first developed in early 50ties and the Japanese government decided to use this method for concentration of sea water to produce salt, which was then produced by solar evaporation. This development program started from 1960 by the Japan monopoly Coop. (at that time). To apply ED process for sea-water concentrat ion it was necessary to develop ion-exchange membranes having very low electric resistance to avoid energy loss due to Joule heat, and those having selectivity to permeate single valent ions only to avoid scale formation in the ED stacks. These Japanese companies, Asahi Glass, Asahi Chemical and Tokuyama Soda, have succeeded to develop such membranes, and until 1971 all of the seven salt manufacturing companies had adopted ED for production of food salt.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.282-285
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• 1999

Fabrication and pakaging method for low delve voltage and 10Gbps Ti diffused waveguide LiNbO$_3$ optical intensity modulator are described. Optical waveguides were prepared by conventionaly electron-beam evaporation and Ti-indiffusion into Z-cut plate LiNbO$_3$. Traveling-wave electrodes were used for obtaining the wideband frequency response and impedance matching. Microwave effective index and characteristic impedance measured by time domain reflectometry and compared with the calculated value by conformal mapping. The characteristics of 10Gbps modulator at the 1550nm wavelength are as follows : perfect modulation voltage Is about 5V, optical insertion loss Is about 5dB, 3-dB bandwidth is 10GHz, and characteristic impedance is about 50$\Omega$.

• Corrosion Science and Technology
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• v.7 no.6
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• pp.332-337
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• 2008

A reaction and evaporation types of cerium based conversion coatings were developed for galvanized steel sheet. The corrosion loss Q(Cb/cm2) and protection efficiency P(%) were obtained using a polarization technique for cerium based conversion coatings on galvanized steel exposed to 0.5N NaCl for 7 days. The microstructure of coating layer was observed using SEM. An excellent corrosion reistnce of galvanized steel was obtained by two types of cerium basd conversion coating. Salt spray test was done to evaluate the corrosion resistance of three samples by visual inspection. The corrosion ranking of three samples-untreated and two treatedby electrochemical data was matched well with the results of salt spray test.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.2 no.1
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• pp.27-36
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• 1990

An experimental investigation was made to study the performance characteristics of evaporator having different fin configurations and tube inner grooves. Three different types of fin such as super slitted fin, slitted fin, plain fin, and two types of tube such as inner grooved tube, and bare tube, are tested varying the air velocity, evaporation temperature and superheat of refrigerant. Results show that in the range of air side Reynolds number $3{\times}10^3\;-\;1.5{\times}10^4$ evaporator with super slitted fin and inner grooved tube shows best performance. It is 80% higher in overall heat transfer coefficient and 2.6 times higher in pressure loss compared to that with plain fin inner grooved tube. Friction factor is found to be almost independent of evaporating temperature and degree of superheat, while Colburn j factor varies with evaporating temperature.

• Nuclear Engineering and Technology
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• v.32 no.5
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• pp.521-529
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• 2000

A modified interfacial heat transfer correlation between a dispersed water droplet and ambient superheated steam is proposed and compared with available experimental data and other correlations. Modified one overcomes the inherent deficiencies of Lee and Ryley's interfacial heat transfer correlation that ignored the effects of steam superheating which can not be neglected especially in the reflood situation of a loss-of-coolant accident. Modified one is represented by (equation omitted) In the present correlation the effect of possible subcooling of a water droplet is not taken into consideration. Comparison of the above correlation with currently available measurement data for a water droplet in high temperature gas flow shows that the proposed one correlates well with the measurement data where the degree of superheating is negligible and considerable.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.1-12
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• 2004

Initial burst is one of the major challenges in protein-encapsulated microparticle systems. Since protein release during the initial stage depends mostly on the diffusional escape of the protein, major approaches to prevent the initial burst have focused on efficient encapsulation of the protein within the microparticles. For this reason, control of encapsulation efficiency and the extent of initial burst are based on common formulation parameters. The present article provides a literature review of the formulation parameters that are known to influence the two properties in the emulsion-solvent evaporation/extraction method. Physical and chemical properties of encapsulating polymers, solvent systems, polymer-drug interactions, and properties of the continuous phase are some of the influential variables. Most parameters affect encapsulation efficiency and initial burst by modifying solidification rate of the dispersed phase. In order to prevent many unfavorable events such as pore formation, drug loss, and drug migration that occur while the dispersed phase is in the semi-solid state, it is important to understand and optimize these variables.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.3
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• pp.58-68
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• 1988

Most of the Korean watersheds are mountaineous and consist of various soil types and land uses And seldom watersheds are found to have long term hydrologic records. The SNUA, a hydrologic watershed model was developed to meet the unique characteristics of Korean watershed and simulate the storm hydrographs from a small mountaineous watershed. Also the applicability of the model was tested by comparing the simulated storm hydrographs and the observed from Dochuk watershed, Gwangjugun, Kyunggido The conclusions obtained in this study could be summarized as follows ; 1. The model includes the simulation of interception, evaporation and infiltration for land surface hydrologic cycle on the single storm basis and the flow routing features for both overland and channel systems. 2. Net rainfall is estimated from the continuous computation of water balance at the surface of interception storage accounting for the rainfall intensities and the evaporation losses at each time step. 3. Excess rainfall is calculated by the abstraction of infiltration loss estimated by the Green and Ainpt Model from the net rainfall. 4. A momentum equation in the form of kinematic wave representation is solved by the finite differential method to obtain the runoff rate at the exit of the watershed. 5. The developed SNUA Model is a type of distributed and event model that considers the spatial distribution of the watershed parameters and simulates the hydrograph on a single storm basis. 6. The results of verification test show that the simulated peak flows agree with the observed in the occurence time but have relative enors in the range of 5.4-40.6% in various flow rates and also show that the simulated total runoff have 6.9-32% of relative errors against the observed. 7. To improve the applicability of the model, it was thought that more studies like the application test to the other watersheds of various types or the addition of the other hydrologk components describing subsurface storages are needed.

• Journal of the Korean Electrochemical Society
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• v.2 no.1
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• pp.46-49
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• 1999

Lithium cobalt oxide cathode for thin-film rechargeable lithium batteries were fablicated by electron-beam evaporation. Annealed lithium cobalt oxide, which was deposited on to stainless steel substrate, showed well-developed (003) planes of the hexagonal structure and potential plateau at $\~3.9 V$. Lithium cobalt oxide thin films had the stoichiometric Li/co ratio at high deposition rates and exhibited high discharge capacity at $15{\AA}/s$. As the annealing temperature increased, discharge capacity increased with maximum value at $700^{\circ}C$, but showed low capacity as a result of reaction with substrate above $700^{\circ}C$. Unuiformity of the lithium and cobalt in the depth profile gave initial capacity loss with charge/discharge performance.