• Transactions of the Korean hydrogen and new energy society
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• v.21 no.5
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• pp.405-411
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• 2010

A 5kW class SOFC cogeneration system consisted of a hot box part, a cold BOP (balance of plant) part, and a hot water reservoir. The hot box part contained a stack, a fuel reformer, a catalytic combustor, and heat exchangers. A cold BOP part was composed of blowers, pumps, a water trap, and system control units. A 5kW stack was designed to integrate 2 sub-modules. In this paper, the 5kW class SOFC system was operated using 2 short stacks connected in parallel to test the sub-module and the system. A short stack had 15 cells with $15{\times}15 cm^2$ area. When a natural gas was used, the total power was about 1.38 kW at 120A. Because the sub-modules were connected in parallel and current was loaded using a DC load, voltages of sub-modules were same and the currents were distributed according to the resistance of sub-modules. The voltage of the first stack was 11.46 V at 61A and the voltage of the second stack was 11.49V at 59A.

• Bulletin of the Korean Chemical Society
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• v.22 no.8
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• pp.903-908
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• 2001

The gene aeg-46.5, which is expressed under anaerobic condition, has putative triple -10 regions and four transcription start sites. The mRNA transcription level and its start point change depending on the aerobic/anaerobic growth condition. RNA polymerase and its regulatory proteins must choose which of three -10 region to use. The putative triple 10 region was mutated to make only one of them function with consensus -10 region sequence (TATAAT) and the other two as non-functional region. The results show that the second and third -10 regions are used for the aerobic/anaerobic expression. The third -10 region is responsible for the high aerobic to anaerobic switch ratio. This suggests that only the last two of the putative triple -10 region have functions on aeg-46.5 gene expression switch control. The phenotype of the mutated promoter was tested in the wild type cell and narL - cell. The results indicate that the control by NarL is independent from the selection of -10 region. The expression patterns on multi-copy plasmids and on single-copy chromosome were compared. These results show that the aerobic/anaerobic switch control of aeg-46.5 is through the choice of -10 region. The mechanism of choosing different -10 region remains to be seen.

• Journal of Electrochemical Science and Technology
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• v.6 no.1
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• pp.26-33
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• 2015

In this study, cell performance and thermal stability of lithium-ion cells with a polyimide (PI) separator are investigated. In comparison to conventional polyethylene (PE) separator, the PI separator exhibits distinct advantage in microporous structure, leading to superior reliability of the cell. The cells with PI separator exhibit good cell performances as same as the cells with PE separator, but their reliability was superior to the cell with PE separator. Especially in the hot-box test at 150 and 180℃, PI separator showed a contraction percentage close to 0% at 150℃, while the PE separator showed a contraction percentage greater than 10% in both width and length. Therefore, the PI separator can be the promising candidate for separators of the next generation of lithium-ion battery.

• Biomedical Science Letters
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• v.14 no.4
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• pp.243-248
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• 2008

The Forkhead box M1 (FoxM1) has been shown to regulate transcription of cell cycle genes essential for $G_1$-S and $G_2$-M progression, including $p27^{kip1}$. The $p27^{kip1}$ gene is a member of the universal cyclin-dependent kinase inhibitor family. Immunohistochemical studies for FoxM1 and $p27^{kip1}$ were performed in 154 lung cancers (69 squamous cell carcinomas (SCC) and 85 adenocarcinomas (ADC)). Immunoreactivity for FoxM1 and $p27^{kip1}$ were found in 79 (51.3%) and 49 (31.8%) out of 154 cases, respectively. Forty-six (58.2%) of the 79 cases with a positive FoxM1 immunoreactivity showed a negative $p27^{kip1}$ expression in 154 lung cancers. According to histologic type, 22 (53.7%) of the 41 SCC cases with a positive FoxM1 immunoreactivity showed a negative $p27^{kip1}$ expression and 24 (63.2%) of the 38 ADC cases with a positive FoxM1 immunoreactivity showed a negative $p27^{kip1}$ expression. The expression of $p27^{kip1}$ was significantly higher in the SCC than in the ADC (P=0.050). There were no significant associations between the FoxM1 and $p27^{kip1}$ expressions and other clinicopathologic factors. These findings suggest that FoxM1 overexpression may diminish the expression of $p27^{kip1}$ protein in lung cancers. Further studies are needed to define the relation between FoxM1 and $p27^{kip1}$ for examining the mechanisms of tissue-specific FoxM1 expression.

• Computational Structural Engineering
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• v.12 no.4
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• pp.69-69
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• 1999

Design of Dangsan Steel Railway Bridge(a part of Seoul Subway Line NO. 2), which is supposed to be replaced after its 15years survice, was done, and the reconstruction has begun in Dec. 1997. The design include new superstruc-ture and bridge piers, retrofitting of the foun-dation, rail system, electric and signal, etc. In this paper, design of the structure is mainly summarized. The main span superstructure, across Han river, is composite section which is com-posed of steel box and reinforced concrete deck slab with 9 span continuous. The superstructure for the approaches is bottom througth type 2-cell steel box girder with steel floor system and concrete deck slab with 3 or 4 span continuous. The bridge piers was planned to be reconstructed based upon the result from the various investi-gations, while the foundation(cassion and pile foundation) was planned to be retrofitted. For superstructure erection, the method of combination of barge bent and heavy lifting and the launching truss method was investigated for the main span and approach spans, respectively.

• Transactions of The Korea Fluid Power Systems Society
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• v.7 no.1
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• pp.6-10
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• 2010

A measurement of very high torque for track drive unit in construction equipment is usually in difficulties due to the requirement of a torque meter with high capacity, and the limitation of geometry for an experimental set-up. To improve the troublesome problem, a new device was proposed, where a torque transmitted through the torque arm can be measured by load cells attached at each torque arm. The experimental set-up of the new device was carried out in order to measure the torque values for a mechanical feedback type planetary gear box, in which the power flow circulates itself in a closed-loop. The new device enables to measure torque values of 60,000Nm. Additionally, the measured values were estimated statistically in the aspect of their repeatability and reproducibility, so that an acceptable behaviour as a measuring device can be confirmed.

• Journal of the Korean Graphic Arts Communication Society
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• v.10 no.1
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• pp.81-90
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• 1992

The charater of standing box printing reguires a rich representation in a light and a shade of color and caues the modern photographs to be abundant of the ink and also shows the continuity of which any other printing is incapable because of its profound gradation. The clear printing in gravure can be said to be due to the good transfer of the ink - the completion of the transference of the ink into the stencil paper and the clear transference of the printing tone. The most inportant matter is the distance between the printing press and the doctor line. It is the matter of the structure and arrangement because of giving the most affect on the dryness of the ink in the cell. The glue of the ink in gravure changes by the kinds of the dye and the cellusolve used. To make the printing somoothly progressive from the high glue of the ink to the low glue of the ink will have to be used, which will be possible to choose the ester.ose the ester.

• BMB Reports
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• v.55 no.3
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• pp.125-135
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• 2022

Continuously renewing the proteome, translation is exquisitely controlled by a number of dedicated factors that interact with the ribosome. The RNA helicase DDX3 belonging to the DEAD box family has emerged as one of the critical regulators of translation, the failure of which is frequently observed in a wide range of proliferative, degenerative, and infectious diseases in humans. DDX3 unwinds double-stranded RNA molecules with coupled ATP hydrolysis and thereby remodels complex RNA structures present in various protein-coding and noncoding RNAs. By interacting with specific features on messenger RNAs (mRNAs) and 18S ribosomal RNA (rRNA), DDX3 facilitates translation, while repressing it under certain conditions. We review recent findings underlying these properties of DDX3 in diverse modes of translation, such as cap-dependent and cap-independent translation initiation, usage of upstream open reading frames, and stress-induced ribonucleoprotein granule formation. We further discuss how disease-associated DDX3 variants alter the translation landscape in the cell.

• Journal of Korean Society of Steel Construction
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• v.15 no.3
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• pp.231-239
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• 2003

Many box girder bridges have been constructed during the past several decades due to their large bending and torsional rigidities as well as aesthetic considerations. However, box girders have shortcoming in that the cross section distorts under an eccentric loading and warps out of the section plane. Therefore, in order to reduce distortional stresses such as distortional warping and transverse bending normal stresses, diaphragms were generally installed in the box girders. Shapes of the diaphragms in steel-box-girder bridges constructed up to date were solid-plate, frame, and truss types. The objectives of this study using parametric study were to evaluate the appropriate stiffness ratio of intermediate diaphragms and then to propose the effective spacing and numbers of intermediate diaphragms based on the evaluated stiffness ratio. Target bridges for this study were straight continuous span bridges with a single-cell steel box section. The parameters for the parametric study were the shape of box section, the span numbers, the equivalent span length, the stiffness of intermediate diaphragms, and the spacing of intermediate diaphragms. From the results of the parametric study, the effective spacing and numbers as well as the stiffness ratio of the intermediate diaphragms will be presented.

• Journal of Life Science
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• v.17 no.1 s.81
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• pp.1-5
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• 2007

The Precesses for leaf development in dicotyledonous plants are surprisingly complex, while the mechanism of controlling and coordinating them is poorly understood. To characterize the fundamental features of the leaf development of Arabidopsis, we first attempted to isolate mutants that alter leaf morphology. Here, leaf morphological mutant of Arabidopsis, lanceolatal (lan1) which has small and narrow leaves have isolated and characterized. To clarify the function of LAN1 in organ development, we characterized lan1-7 mutant using an anatomical and genetic approach. The lan1-7 mutant had reduced size of foliage leaves and reduced dimensions of stems. A reduction both in cell size and in cell number was evident at the cellular level in the lan1 mutant, revealing that LAN1 gene appears to affect cell division at an earlier stage and cell elongation throughout the development of leaf primordia. from the analysis of heterogeneous plant with lan1 mutation and 35S-AG transgenic plant, AG gene is revealed to regulate leaf morphology under the control of 35S promoter. Thus, MADS-box gene was revealed to have some relationship to that of LAN1 gene at certain stage in leaf development processes.