• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.381-388
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• 2000

Ceramic foam prepared with cordierite as a starting material by foam method was tested to evaluate the feasibility as a filter for the dust collection in hot gas. Two different types of agents Benzethonium chloride (BZTC, C27H42NO2Cl) and Sodium Lauryl Sulfate(SLS, CH3(CH2)11OSO3Na) were used as foaming agents in foaming process. Porosityof ceramic foam was about 80% and mean pore size were 100${\mu}{\textrm}{m}$ for SLS agent and 200 ${\mu}{\textrm}{m}$ for BZTC. It was observed that ceramic foam was composed of continuous macro-pore structure with opening windows interconnecting macro-pores. The surface of ceramic foam support of was coated with cordierite particles ranged from 20${\mu}{\textrm}{m}$ to 50${\mu}{\textrm}{m}$ Meso-pore size in the coating layer on ceramic foam was below 10${\mu}{\textrm}{m}$. While air permeability of the support increased with increasing macro-pore size coated ceramic filters showed a constant permeability without regard to the macro-pore size of the support. The permeabuilities of support varied in the range of 600$\times$10-13m2 to 1000$\times$10-13m2. For the case of coated ceramic filter it was about 200$\times$10-13m2. As a result of particle trapping test by using fly ash the particle removal efficiency was over the 99.9%.

• The Journal of the Korea Contents Association
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• v.17 no.10
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• pp.452-462
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• 2017

This study proposes community based web service for contents providers and web designers to provide user-centered approach on Wordpress theme search and customizstion process. The contents and structure of theme information is analyzed and online communities on programming and Wordpress are studied to development of community based, theme contents service scenario. As a result, I launched 'Themettack' web service, I took beta testing with 20 users for 2 weeks, and found that theme template image and ideal theme contest services are the most satisfactory experiences. Various community contents which tested in this study and user participation data provided proper directions of Wordpress theme service as open source platform.

• Journal of Applied Biological Chemistry
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• v.51 no.6
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• pp.302-306
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• 2008

To evaluated active principles for diabetic compolications from the Taraxacum mongolicum (T. mongolicum), Cirsium japonicum (C japonicum), and Cirsium setidens (C. setidens) and its constituents, as well as silymarin tested for their effect on rat lens aldose reductase. As a result, the MeOH extract of T. mongolicum ($IC_{50}\;8.71\;{\mu}g/mL$) have strong lens aldose reductase inhibition abilities. Also, Aldose reductase inhibitory showed an isolated luteolin ($IC_{50}\;20\;{\mu}M$) from the T. mongolicum and sliymarin ($IC_{50}\;13\;{\mu}M$).

• Agricultural and Biosystems Engineering
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• v.5 no.1
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• pp.5-9
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• 2004

This study was carried out to develop methods of reducing the effect of solar illumination on pixel gray-levels of machine vision for agricultural field use. Two kinds of monochrome CCD cameras with manual and auto-iris lenses were used to take pictures within a range of 15 to 120 klux of solar illumination. A camera having more precise automatic control functions gave much better result. Four kinds of indices using pixel gray-level of the $99\%$ white DRS (diffuse reflectance standard) as a reference were tried to compensate pixel gray-levels of an image for variable illumination. Coefficients of variation of the indices within a range of illumination were used as a criterion for comparison. The study concluded that an index of (A+B)/A, where A is gray-level of the $99\%$ DRS and B is gray-level of the tested material, gave the best consistency in the range of solar illumination.

• Analytical Science and Technology
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• v.5 no.1
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• pp.91-96
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• 1992

A simple and cheap AC voltammeter was manufactured in our lab. This instrument consists of a DC function generator and a lock-in amplifier. We tested this instrument in some chemical systems. Our data, CV voltammogram and AC voltammogram, obtained form using a Pt working electrode in 1M $H_2SO_4$ and a reversible system of $1{\times}10^{-3}M$ ${Fe(CN)_6}^{3-}$ proved our system works well. The quantitative result of iodine is also obtained.

• Archives of design research
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• v.15 no.4
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• pp.231-242
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• 2002

Due to the various reasons reducing the advertising effects in such as message reliability declining, target segmentation, and information technology, creative becomes more important than ever before. And this is more true in print advertising than electronic ones. The purpose of this study is to support to develop more effective advertisement in print advertising. Parody advertising, a postmodernic technique, effectiveness was tested empirically. Top-of-mind awareness, reliability toward advertising, attitude toward advertising, attitude toward brand, and purchase intention were adapted as a scale to measure the effectiveness of parody and non-parody advertising. Result proved the parody advertising shows higher effects than non-parody one. Conclusively saying that parody could be one of the possible ways to increase effects on print advertising to survive from the heavy competition and low attention.

• Journal of Astronomy and Space Sciences
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• v.37 no.3
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• pp.199-208
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• 2020

This paper presents a kinematic ephemeris generator for Korea Pathfinder Lunar Orbiter (KPLO) and its performance test results. The kinematic ephemeris generator consists of a ground ephemeris compressor and an onboard ephemeris calculator. The ground ephemeris compressor has to compress desired orbit propagation data by using an interpolation method in a ground system. The onboard ephemeris calculator can generate spacecraft ephemeris and the Sun/Moon ephemeris in onboard computer of the KPLO. Among many interpolation methods, polynomial interpolation with uniform node, Chebyshev interpolation, Hermite interpolation are tested for their performances. As a result of the test, it is shown that all the methods have some cases that meet requirements but there are some performance differences. It is also confirmed that, the Chebyshev interpolation shows better performance than other methods for spacecraft ephemeris generation, and the polynomial interpolation with uniform nodes yields good performance for the Sun/Moon ephemeris generation. Based on these results, a Kinematic ephemeris generator is developed for the KPLO mission. Then, the developed ephemeris generator can find an approximating function using interpolation method considering the size and accuracy of the data to be transmitted.

• Journal of the Korean Society of Food Culture
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• v.32 no.1
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• pp.10-17
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• 2017

This study aimed to examine the effects of transformational leadership on employees' trust, perceived support from superiors, organizational citizenship behavior, and moderating effects of locus of control. Using the Amos program, this study tested reliability and fitness of the research model and verified five hypotheses based on empirical data from 233 employee samples in coffee shops. The result of this study shows that positive consideration and charisma of transformational leadership positively influenced employees' level of trust toward superiors and perceived support from superiors. Trust had positive effects on promotion of organizational citizenship behavior of employees. Lastly, analysis of the moderating effect of locus of control showed that a lower level of extrinsic control and higher level of intrinsic control were both positively correlated with greater receptiveness to transformational leadership. The findings in this study identified several significant factors of employee effectiveness influenced by transformational leadership in the coffee shop industry. Limitations and future research directions are also discussed.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.4
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• pp.395-403
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• 2013

Fishing efficiency of the squid jigging vessel using the LED and metal halide fishing lamp combination was analyzed to reduce the cost for fishing operation utilizing the fishing light system for high degree of efficiency in the squid jigging fishery (one of the representative coastal and offshore fisheries in Korea). This study aims to improve the nature of existing LED lamps and to develop fan-shaped LED lights having 180W of power and ${\pm}45^{\circ}$ angle of light intensity distribution. The marine experiment for making a comparison of their fishing efficiency was tested by a 9.77 tons fishing vessel from Oct. through Dec. 2012. As a result, experimental fishing vessel showed slightly higher fishing efficiency than the average of metal halide lamp-equipped vessel and 20% energy savings. This means that the combination of LED and metal halide lamps would provide an efficient way to lower energy consumption while maintaining fishing efficiency.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.1
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• pp.61-68
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• 2001

A rotor system is composed of a rotating shaft with supporting bearings. The rotor system is widely used in every rotating machinery such as the turbine generator and the high precision machine tools. A negligible error or malfunction in the rotor, however, can cause a catastrophic failure in the system then result in the environmental and economic disasters. A diagnosis of the rotor system is important in preventing these kinds of failures and disasters. Up to now, many researchers have devoted in the development of diagnosing tools for the system. The basic principles behind the tools are to retrieve the data through the sensors for a specific state of the system and then to identify the specific state through the heuristic methods such as neural network, fuzzy logic, and decision matrix. The proper usage of the heuristic methods will enhance the performance of the diagnostic procedure when together used with the statistical signal processing. In this paper, the methodologies in using the above 3 heuristic methods for the diagnostics of the rotor system are established and also tested and validated for the data retrieved from the rolling element bearing and journal bearing supported system.