• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.103-112
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• 1993

The rates of overall mass transfer of n-butyl acetate in the alkaline hydrolysis of n-butyl acetate were measured by using a mechanically agitated vessel in order to get the relationship between the mass transfer rates and experimental variables. The interfacial area between liquid-liquid heterogeneous phases could be obtained by comparing the theoretical values of reaction enhancement factor from an approximated solution of a diffusion equation based on the film theory with the experimental data.

• Fire Science and Engineering
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• v.20 no.2 s.62
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• pp.21-30
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• 2006

Since Daegu subway arson fire disaster in 2003, there have been several copycat crimes such as at Seoul Metro line number seven and Hongkong Chuiwan line cases. Oil and gas were used for fire propagation in most cases as in Daegu case and such fire could be expanded to a whole subway cabin within several minutes. The fire may eventually cause the whole subway system stop. Fire damage can be minimized when fire occurrence and diffusion are blocked by stages or isolated rapidly. This study suggests an effective early response system that separates passengers from fire and a real-time fire extinguishment program by stages. Based on the subway arson case studies, the early response scenario has been structured by three stages, i.e., confirmation of fire and damage, early fire extinguishment, and information dissemination and passengers evacuation.

• Proceedings of the KIEE Conference
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• 1998.07e
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• pp.1770-1772
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• 1998

This study is concluded under by investigation about the lighting environment on a blackboard in elementary, middle, high school of inchon metropolitan. 1. The illumination was approximated to standard value in the side of quantity by the result of the Mimistry of Education's command. However, the uniformity of illuminescence was relatively increased. 2. In order to raise the blackboard lighting, we installed local lighting fixture for blackboard but most of schools are directly adopted to the way of sticking to the blackboard and the lower part of the blackboard is not effective. So that it is desirable of teacher and students to put the local lighting in front of the higher part of the blackboard or install in setting the perfect diffusion light from the ceiling. 3. Deviation of luminance is also more groat when local lighting exist for blackboard. And, regardless of local lighting, luminance of blackboard in side of window, from direction of floor is high because of regular reflected light. Therefore a curtain or blind must be installed pertinently.

• Asia-Pacific Journal of Business
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• v.5 no.2
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• pp.13-24
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• 2014

The objective of this research is to find out the factors affecting adoption of Internet banking in India. The data is based upon a survey of 150 bank customers using a convenience sampling technique with the aid of a structured self-administered questionnaire. The research model was analyzed using Partial Least Squares (PLS) analysis. The recommended procedures have been tested which is measurement model and structural model. Perceived Usefulness, Perceived Ease of Use, Perceived Risk, Image, Results Demonstrability, Perceived Behavioral Control and Subjective Norm were influence intention to use Internet banking. However, Perceived Ease of Use, Perceived Credibility and Computer Self Efficacy were not influence intention to use Internet banking. The findings of this study are expected to be of great use to the bank marketers. An understanding of the factors identified in this study allows bank managers to direct efforts and resources in the most effective and efficient way to increase bank business in the long run and encourage their bank customer's to adopt Internet banking. Moreover, this paper contributes to the empirical literature of diffusion of financial innovations, particularly Internet banking in a developing country, such as India.

• The KSFM Journal of Fluid Machinery
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• v.7 no.6 s.27
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• pp.28-37
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• 2004

An experimental study is conducted to investigate flow characteristics on a small axial-type turbine which is applied as the rotating part of air tools. It operates in a partial admission due to consumption restriction of the high pressure air. In this operating condition, it is necessary to understand flow characteristics for obtaining the high specific output power. Tested turbine consists of two stages and the mean radius of flow passage is less than 10mm. A 6 bar pressure air is used to operate the turbine. The experimental results show that flow angles depend on the measuring location along the circumferential direction, but its discrepancy is alleviated along the axial direction. Absolute flow velocities show three times difference according to the measuring location at the exit of the first rotor due to the partial admission, but they show similar value at the exit of the second rotor by the velocity diffusion. From the measured flow angles and velocities, a ratio of output power obtained by the first and second rotor is estimated. It shows that the output power obtained by the second rotor is about $11\%$ to that by the first rotor at 60,000 RPM. It is effective therefore to improve the first rotor for increasing the turbine output power.

• Proceedings of the Korean Magnestics Society Conference
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• 2013.12a
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• pp.89-89
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• 2013

Rare earth (RE) - transition metal based high energy density magnets are of immense significance in various engineering applications. $Nd_2Fe_{14}B$ magnets possess the highest energy product and are widely used in whole industries. Simultaneously, composite alloys that are cheap, cost effective and strong commercially available have drawn great attention, because rare-earth metals are costly, less abundant and strategic shortage. We designed rare-earth free alloys and fabrication process and developed novel route to prepare $Nd_2Fe_{14}B$ powders by wet process employing spray drying and reduction-diffusion (R-D) without the use of high purity metals as raw material. MnAl-base permanent magnetic powders are potentially important material for rare-earth free magnets. We have prepared the nano-sized MnAl powders by plasma arc discharge and micron-sized MnAl powders by gas atomization. They showed good magnetic property, compared with that from conventional processes. $Nd_2Fe_{14}B$ powders with high coercivity of more than 10 kOe were successfully synthesized by adjusting R-D step, followed by precise washing system. It is considered that this process can be applied for the recycling of RE-elements extracted from ewaste including motors.

• Journal of the Semiconductor & Display Technology
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• v.19 no.3
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• pp.30-35
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• 2020

A microlens has been fabricated by various methods such as a thermal reflow, hot embossing, diamond milling, etc. However, these methods require a relatively complex process to control the microlens shape. In this work, we report on a simple and cost-effective method to fabricate a cylindrical microlens (CML), which can diffuse light widely. We have employed a slot-die head with the dual plate (a meniscus guide with a protruded μ-tip and a shim with a slit channel) for coating of a narrow stripe using poly(methyl methacrylate) (PMMA). We have shown that the higher the coating gap, the lower the maximum coating speed, which causes an increase in the stripe width and thickness. The coated PMMA stripe has the concave shape. To make it in the shape of a convex microlens, we have applied the thermal reflow method. When the stripe thickness is small, however, its effect is negligible. To increase the stripe thickness, we have increased the number of repeated coating. With this scheme, we have fabricated the CML with the width of 223 ㎛ and the thickness of 7.3 ㎛. Finally, we have demonstrated experimentally that the CML can diffuse light widely, a feature demanded for light extraction efficiency of organic light-emitting diodes (OLEDs) and suppression of moiré patterns in displays.

• Journal of Veterinary Clinics
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• v.19 no.4
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• pp.426-428
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• 2002

A seven-year old mare had endometritis after history of abortion and repeated intra-uterine infusion of antibiotics. She showed hyperemia and oedema of the cervical mucosa with grayish white purulent discharge. Candida albicans was determined to be the causative agent of the endometritis. The diagnosis was established by the direct demonstration of the pathogen in the uterine exudate and its isolation in pure, heavy and luxuriant growth. In vitro disc diffusion test showed the organism was sensitive to all the four antifungal drugs tested, which are amphotericin B, clotrimazole, fluconazole and nystatin. The intrauterine nystatin infusion was found very effective as C. albicans could not be recovered 7 days after the last treatment.

• Preventive Nutrition and Food Science
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• v.4 no.2
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• pp.97-102
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• 1999

Antimicrobial activity and chemical composition of volatile flavor extracts from Agastache rugosa were investigated. The volatile flavor extracts were obtained from leaves and stems of Agastache rugosa by simultaneous distillation extraction (SDE) method. Antimicrobial activity was investigated by disc diffusion and broth dilution methods against several microorganisms of Bacillus cereus, bacillus megaterium, Bacillus subtilis, Corynebacterium xerosis, Staphylo coccus aureus, Staphylococcus epidermidis, Agrobacterium rhizogenes , Agrobacterium tumefaciences, Enterobacter cloacae, Escherichia coli, Salmonella typhi, Vibrio parahaemolyticus, Candida utilis and Saccharomyces cerevisiae. Volatile flavor extractsfrom leaves have strong antimicrobial activity against C.utilis and S.cerevisiae. When 0.12% volatile flavor extracts from fresh leaves were included in the medium, lag phase of C. utilis was extended 6 hr and that of S.utilis and S.cerevisiae was extended 2hr. Further analyses were performed to elucidatethe effective component of the extracts. The major component of volatile flavor was estragole, a phenolic compound. Minor components were determined to be terpenes , alcohols, acids , esters, ketones and aldethydes.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.2
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• pp.74-81
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• 2017

In this study, the combined-type diffuser developed by the Authors, in a previous study, was applied to a residential space. The performance of a ventilation and thermal environment, created by the use of a combined-type diffuser was compared to the pan-type diffuser widely used in apartment houses. In cooling conditions, because of the relatively high air flow rate of ceiling cassette-type air conditioners, the characteristics of airflow distribution in a room were governed by the air conditioner's airflow. In heating conditions, because of the low air flow rate of the diffuser, the characteristics of airflow distribution were governed by the buoyancy effect created by cold external walls and a hot floor. In terms of the Air Diffusion Performance Index (ADPI), which is a thermal environmental index, the result of a combined-type diffuser was greater than a pan-type diffuser in both of cooling and heating conditions. Consequently, the combined-type diffuser showed equal or superior ventilation and thermal environment performance compared to a pan-type diffuser.