• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.214-215
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• 2007

Unstable sustain discharges can occur at the bottom cells of the panel at high temperature. To solve this phenomenon, the wall charge variation during an address period was investigated. A test panel of 7.5 inch XGA level was used and one green cell was measured. In order to realize operating condition equal to that of the bottom cells of 50 inch panel, the addressing stress pulses are applied. It seems that the resultant wall charge loss during address period increased with increase of temperature as well as the addressing stress pulse voltage. Therefore it results in unstable discharge during sustain period.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.676-682
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• 2009

Devolatilization of the Refuse Derived Fuel(RDF) which is produced at WonJu in Korea was characterized in air atmosphere with variation of heating rate(10, 20 and $30^{\circ}C/min$) in TGA. The results of TG Analysis have shown that the pyrolysis and char combustion of the RDF occurred in the range of $350{\sim}700^{\circ}C$ depending on the heating rate. Activation energy of the RDF which was determined by using Friedman and Ozawa-Flynn-Wall method was in the range of 14.44~18.40 kcal/mol. Also, reaction order(n) and pre-exponential factors(A) were 1.219 and $3.02{\times}10^5$ by using Friedman method, respectively. In order to find out the devolatilization mechanism of the RDF, twelve solid-state mechanisms defined by Coats Redfern Method were tested. The results of the Coats Redfern Method have shown that chemical reaction is the effective mechanism by comparison with the value of the activation energy which was derived from the Friedman and Flynn-Wall-Ozawa method and correlation coefficient from twelve solid-state mechanisms of Coats Redfern Method. The solid state decomposition mechanism of the RDF was found to be a decelerated $F_1$ type, random nucleation with one nucleus on the individual particle.

• Advances in aircraft and spacecraft science
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• v.5 no.1
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• pp.21-49
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• 2018

In this paper, geometric nonlinear bending characteristics of single wall carbon nanotube reinforced composite (SWCNTRC) doubly curved shell panels subjected to uniform transversely loadings are investigated. The nonlinear mathematical model is developed for doubly curved SWCNTRC shell panel on the basis of higher-order shear deformation theory and Green- Lagrange nonlinearity. All nonlinear higher order terms are included in the mathematical model. The effective material properties of SWCNTRC are estimated by using Eshelby-Mori-Tanaka micromechanical approach. The governing equation of the shell panel is obtained using the total potential energy principle and a Newton-Raphson iterative method is employed to compute the nonlinear displacement and stresses. The present results are compared with published literature. The effect of SWCNT volume fraction, width-to-thickness ratio, radius-to-width ratio (R/a), boundary condition, linear and nonlinear deflection, stresses and different types of shell geometry on nonlinear bending response is investigated.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.293-298
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• 2019

A marine ulvalean species (Chlorophyta) was collected from the eastern coast of Korea. This species is morphologically characterized by a distromatic, dark to medium green and mostly irregularly orbicular or irregularly expanded thallus with entire or undulate margin without serrations. Vegetative cells are irregularly polygonal with distinctly rounded corners in shape, and have chloroplast completely covering the outer cell wall and one to two pyrenoids per cell. In a phylogenetic tree based on ITS (Internal Transcribed Spacer) sequences, this Korean alga nests in the same clade with Ulva sublittoralis, as a sister clade of U. californica, U. flexuosa and U. tanneri, which share the irregularly orbicular or expanded thallus normally without teeth cells. The genetic divergence between them is intraspecific within Ulva. Accordingly, it is identified as U. sublittoralis based on the morphological and molecular data. This is the first record of Ulva sublittoralis in the Korean marine algal flora.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.77-82
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• 2013

Phyllodictyon anastomosans (Harvey) Kraft et M.J. Wynne and Saccharina ochotensis (Miyabe) E.E. Lane C. Mayes, Druehl et G.W. Saunders are first recorded in Korea. A pantropical green alga, P. anastomosans was collected on a rock wall in the subtital zone of Jeju Island. This species has very tiny fan-shaped and netted thalli that are green in color. A cold temperate brown alga, P. ochotensis has very thick and leathery thalli that are deep brown in color. Morphological characteistics and habitats of these species are described with taxonomic accounts.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.139-140
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• 2011

The government encourages adoption of Rahmen structure design to ensure efficient management of national resources. However, in comparison with bearing-wall structure, Rahmen structure requires higher unit construction cost and present challenges in terms of securing adequate floor area ratio and floor height. That is why project clients have been disinterested in adoption of Rahmen structure design. Therefore, we have attempted to find factors having influence on decline of project viability for Rahmen structure. This study will be utilized as a basic reference study for promotion of Green Frame design which is a composite PC structure already developed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.29-30
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• 2011

A Green Frame is a composite Rahmen precast concrete structure that utilizes the advantages of the steel frame and the reinforced concrete. Compared to bearing wall structure, the precast concrete structure may raise construction cost If the precast concrete members are produced in plant. Thus, if the precast concrete members can be produced in site, the cost-effectiveness and quality shall be increased. Various site conditions must be considered and reviewed to ensure a space for the in-situ production. Therefore, this study focuses on the basic study on the arrangement of in-situ production module of composite precast concrete members.

• Journal of Environmental Science International
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• v.14 no.8
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• pp.719-722
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• 2005

This study is to find the effective way to green perpendicular wall spaces as soon as possible and to get basic data for activating the perpendicular greening on high story building through the experiment of container-type planting ground in which lightened artificial soil mixed with rock wool was put. Comparative studies of the sizes of containers and soil were carried out but separate management was not performed. Four plants(Euonymus fortunei var. radicans, Lonicera japonica, Parthenocissus quinquefolia, Parthenocissus tricuspidata) which have the capability to cover and screen perpendicular spaces were used in the experiment. In result, a container must be equipped with over 15cm depth soil mixed with less than $30\%$ of rock wool.

• Journal of Microbiology and Biotechnology
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• v.30 no.6
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• pp.878-884
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• 2020

Penicillium digitatum and P. italicum are the two important postharvest pathogens in citrus, causing about 90% of the total loss of citrus fruit during storage and transportation. Natural fungicides such as essential oils have been widely used instead of chemical fungicides for preventing and controlling postharvest diseases. In this research, p-anisaldehyde exhibited a strong inhibitory effect on P. digitatum and P. italicum, with the minimum inhibitory concentration and minimum fungicidal concentration values of both being 2.00 μl/ml. Additionally, p-anisaldehyde visibly inhibited both the green mold and blue mold development of citrus fruits inoculated with P. digitatum and P. italicum. The mycelia morphologies of these pathogens were greatly altered, and the membrane permeability and cell wall integrity of mycelia were severely disrupted under p-anisaldehyde treatment. These results suggest that the antifungal activity of p-anisaldehyde against P. digitatum and P. italicum can be attributed to the disruption of the cell wall integrity.

• KIEAE Journal
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• v.17 no.4
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• pp.75-81
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• 2017

Purpose: Most contemporary office buildings supply external views, a sense of openness and a sense of time to their occupants by adopting the curtain walls, which are equipped with an outer cover having large window area. As a result, the amount of radiation increases, adversely affecting cooling load during the summer in office buildings. Although solar radiation decreases heating load and reduces energy costs during the winter period, due to the characteristics of offices where occupants work largely during daytime, the cooling load is important compared to the heating. Therefore, diverse measures to resolve those trade-offs and annual energy cost have been investigated. Method: In this study, the annual thermal load was comparatively analyzed according to the slat angle of the venetian blind along with lighting control technique. Result: After selecting effective conditions, in order to resolve such issues, this study established automated control strategies of slat angle depending on the window-to-wall ratio and zone orientation, so that the findings of this study can be effectively generalized to other circumstances.