• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.71.2-71
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• 2003

Ralstonia solancearum infects many solanaceous plants, however race 3 infects only potato and tomato weakly. To identify genes responsible for race specificity of R. solanacearum, we mobilized genomic library of LSD2029 (race 3) into LSD341 (race 1) and inoculated 1,000 transconjugants into hot pepper. One transconjugant that did not induce wilt symptom in hot pepper was isolated. We found that a cosmid clone, pRSl, conferred avirulence to LSD341. By deletion and mutational analyses of pRSl, we found the 0.9-kb PstI/Hindlll fragment carries avirulence functions. We sequenced the fragment and identified one possible open reading frame, a rsal gene, possibly encoding 110 amino acids. The rsal was preceded with a plant-inducible promoter (PIP) box, indicating that the gene might be regulated by HrpB. Interestingly, the promoter region of the rsal homolog in the strain GM11000 (race 1) did not have the PIP box. Rsal did not show any significant homologies with proteins in the database, indicating th e protein is different from the previously reported avirulence proteins. When we mutated the rsal gene by marker-exchange in LSD2029, the mutant was less virulent in potato.

• International journal of steel structures
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• v.18 no.5
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• pp.1589-1597
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• 2018

Fatigue tests and numerical analysis were carried out to evaluate the fatigue performance at the U-rib to deck welded joint in steel box girder. Twenty specimens were tested corresponding to different penetration rates (80 and 100%) under fatigue bending load, and the fatigue strength was investigated based on hot spot stress (HSS) method. The detailed stress distribution at U-rib to deck welded joint was analyzed by the finite element method, as well as the stress intensity factor of weld root. The test results show that the specimens with fully penetration rate have longer crack propagation life due to the welding geometry, resulting in higher fatigue failure strength. The classification of FAT-90 is reasonable for evaluating fatigue strength by HSS method. The penetration rate has effect on crack propagation angle near the surface, and the 1-mm stress below weld toe and root approves to be more suitable for fatigue stress assessment, because of its high sensitivity to weld geometry than HSS.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.17-18
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• 2016

On apartment construction sites in hot weather environments, the high temperature of 30℃ and above and radiation from the sun cause iron and mold temperatures to rise, which lowers worker efficiency and has a negative effect on the deposited concrete. Therefore this study measured the temperature of D10 ~ D16 iron and aluminum items actually used on box frame apartment construction sites currently under construction, in order to give reference information to solve hot weather concrete problems. The temperature measurement results showed that for iron, temperatures rose to around 45℃, and for mold around 58.8℃, calling for safety measures for workers in case of possible burning and other problems.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.5
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• pp.609-615
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• 2011

A 5 kW class SOFC system for cogeneration power units was consisted of a hot box part and cold BOPs. High temperature components such as a stack, a fuel reformer, a catalytic combustor, and heat exchanges are arranged in the bot box considering their operating temperatures for the system efficiency. The hot box was made of ceramic boards for the thermal insulation. A 5 kW class SOFC stack was composed of 2 sub-modules and each module had 64 cells with $15{\times}15cm^2$ area and stainless steel interconnects. The 5 kW class SOFC system was operated with a hydrogen and a city gas. With a hydrogen, the total power of the stacks was about 7.1 kWDC and electrical efficiency was about 49.3% at 80 A. With a city gas, the total power of the stacks was about 5.7 $kW_{DC}$ and electrical efficiency was about 38.8% at 60 A. Under self-sustained operating condition, the system efficiency including a power conditioning loss and a consumed power by BOPs was about 30.2%.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.77.2-78
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• 2003

An EREBP/AP2-type transcription factor (CaPFl) was isolated by DDRT-PCR following inoculation of soybean pustule pathogen Xanthomonas axonopodis pv. glycines Bra which induces HR on pepper leaves. Genomic Southern blot analysis revealed that the CaPFl gene is present as a single copy within the hot pepper genome. The deduced amino acid sequence of CaPFl has two potential nuclear localization signals, a possible acidic activation domain, and an EREBP/AP2 motif that could bind to a conserved cis- element present in promoter region of many stress-induced genes. The mRNA level of CaPFl was induced by both biotic and abiotic stresses. We observed higher-level transcripts in resistance-induced pepper tissues than diseased tissues. Expression of CaPFl is also induced upon various abiotic stresses including ethephon, MeJA, cold stress, drought stress and salt stress treatments. To study the role of CPFI in plant, transgenic Arabidopsis and tobacco plants which express higher level of pepper CaPFl were generated. Global gene expression analysis of transgenic Arabidopsis by cDNA microarray indicated that expression of CaPFl in transgenic plants affect the expression of quite a few GCC box and DRE/CRT box-containing genes. Furthermore, the transgenic Arabidopsis and tobacco plant, expressing CaPFl showed tolerance against freezing temperature and enhanced resistance to Pseudomonas syrnigae pv. tabaci. Taken together, these results indicated that CaPFl is a novel EREBP/AP2 transcription factor in hot pepper plant and it may has a significant role(s) in regulation of biotic and abiotic stresses in plant.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.361-364
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• 2009

KEPRI has studied planar type SOFC stacks using anode-supported single cells and kW class co-generation systems for residential power generation. A 1kW class SOFC system consisted of a hot box part, a cold BOP part and a water reservoir. A hot box part contains a SOFC stack made up of 48 cells with $10{\times}10cm^2$ area and ferritic stainless steel interconnectors, a fuel reformer, a catalytic combustor and heat exchangers. Thermal management and insulation system were especially designed for self-sustainable operation. A cold BOP part was composed of blowers, pumps, a water trap and system control units. When a 1kW class SOFC system was operated at $750^{\circ}C$ with hydrogen, the stack power was 1.2kW at 30 A and 1.6kW at 50A. Turning off an electric furnace, the SOFC system was operated using hydrogen and city gas without any external heat source. Under self-sustainable operation conditions, the stack power was about 1.3kW with hydrogen and 1.2kW with city gas respectively. The system also recuperated heat of about 1.1kW by making hot water. Recently KEPRI developed stacks using $15{\times}15cm^2$ cells and tested them. KEPRI will develop a 5 kW class CHP system using $15{\times}15cm^2$ stacks by 2010.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.28 no.4
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• pp.153-157
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• 2016

In case of metal insulation, which is produced by stacking stainless steel sheets and air layers in a multi-stack manner at a specific thickness, insulation performance will be evaluated based on thermal transmittance rather than the intrinsic physical properties of each material such as thermal conductivity. However, there is no standard for measuring thermal transmittance targeted for non-homogeneous insulation which is used in relatively high temperature conditions such as a power station. In this study, the thermal conductivity of homogeneous insulation acquired by the standardized guard hot plate method and the thermal conductivity of homogeneous insulation measured by the newly developed performance tester were compared to verify the confidence level of the tester. As a result, thermal conductivity acquired by the newly developed thermal transmittance tester was about 6% higher than the thermal conductivity measured by the existing guard hot plate method under the anticipated service temperature conditions.

• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.177-180
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• 2010

Purpose: As PET test came to be covered by the pay system of medical insurance (July 1, 2006) and the needs for it becoming increased for laboratory purpose, it became necessary to purchase expensive medical equipments to solve those problems. However, as most of equipments that are operated by cyclotron are very expensive as to amount from tens of millions up to hundreds of millions of won, it is difficult to purchase those equipments from the point of medical organizations. It may be possible to self manufacture those equipments with least costs if their parts functions that meets the operators demands. The Nuclear Medicine department of National Cancer Center (NCC) is trying to manufacture and use equipments that can be made with least costs, including introducing 2 medical equipments that can improves the operator's works. Materials and Methods: Example 1: Self production of radioisotope($^{18}F$) divider was fabricated. The NCC's Nuclear Medicine department acquired one acrylic panel, seven 3-way valve, tubing etc. that can be found in the market to make the main body of divider in cooperation with biomedical engineering, and placed them inside hot cell, and installed switching box outside of hot cell to make it possible to control them from outside. This main body of divider were placed in radioisotope transfer line that are manufactured in the cyclotron. Example 2: Self production of $^{18}F$-FDG automated divider was fabricated. The NCC's Nuclear Medicine department used cavro pump syringe that consists the main body of divider in cooperation with biomedical engineering, biomedical engineering developed programs that divides a certain amount. $^{18}F$-FDG automated divider is placed inside hot cell, and cable chords were used in the equipment, and then it was connected to PC outside hot cell to make it possible to control the $^{18}F$-FDG automated divider. Results: From the NCC's Nuclear Medicine department tests that were carried out from March, 2007 until now, we found out that radioisotope can be sent to radiopharmaceuticals composite module we want, and from the tests that are carried out at NCC's Nuclear Medicine department using $^{18}F$-FDG automated divider since August, 2009 it was possible to distribute radiopharmaceuticals into vial intended. Conclusion: Through the two examples above, we found out that costs can be reduced by self manufacturing expensive equipments from NCC's cyclotron room with least costs. Also, it decreased radiation exposure dose on workers, and set up problem solving processes in cooperation with lots of parties related.

• Journal of Welding and Joining
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• v.33 no.2
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• pp.23-31
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• 2015

Stainless steel is used in automobile muffler and exhaust systems. However, in comparison with other steels it has a high thermal expansion rate and low thermal conductivity, and undergoes excessive thermal deformation after welding. To address this problem, we evaluated the use of arc brazing in place of welding for the processing of an exhaust system, and investigated the parameters that affect the joint characteristics. Muffler parts STS439 and hot-dipped Al coated steel were used as test specimens, and CuAl brazing wire was used as the filler metal for the cold metal transfer (CMT) welding machine, which is a low heat input arc welder. In addition, a Box-Behnken design of experiment was used, which is a response surface methodology. The main process parameters (current, speed, and torch angle) were used to determine the appropriate welding quality and the mechanical properties of the brazing part was evaluated at the optimal welding condition. The optimal processing condition for arc brazing was 135A current, 51cm/min speed and $74^{\circ}$ torch angle. The process was applied to an actual exhaust system muffler and the prototype was validated by thermal fatigue, thermal shock, and endurance limit tests.

• Journal of the Korean Solar Energy Society
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• v.36 no.4
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• pp.41-47
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• 2016

A bypass diode is connected in parallel to solar cells with opposite polarity. The advantage of using the bypass diode is circumvented a destructive efforts of hot-spot heating in the photovoltaic(PV) module. In addition, it is possible to reduce a energy loss under the partial shading on the PV module. This paper presents a characteristic of photovoltaic module under partial shading condition and with defective bypass diode by using the experimental data. The results of field testing for each photovoltaic modules, when photovoltaic system which is connected power grid is operating, the inner junction-box temperature of shading photovoltaic module is high $5^{\circ}C$ because of difference of flowing current through into bypass diode. And incase of not operating photovoltaic system, the inner junction-box temperature of module with defective bypass diode is greatly higher than partial shading PV module.