• Journal of Radiation Industry
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• v.4 no.3
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• pp.209-213
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• 2010

Bacterial blight is one of the most serious diseases of rice (Oryza sativa L.), and it has been known that Xanthomonas oryzae pv. oryzae (Xoo) causes this disease symptom. To develop resistance rice cultivars against Xoo, 3,000 lines of $M_3$ mutants, which were irradiated with gamma ray, were tested by 'scissor-dip method' primarily, and 191 putative resistant lines were selected. In $M_4$ generation, these lines were screened again with various ways such as measuring of symptom of bacterial blight in leaf, number of tiller, fresh weight, and phenotypic segregation ratio in next generation. Finally, six resistance lines were selected. RT-PCR analysis revealed that these lines displayed high level of R-genes such as Xa21, Pi36, and Pi-ta. These results indicate that mutations by gamma ray cause disruptions of regulatory signal transduction systems of these R-genes. Furthermore, these selected mutants could be useful for the development of rice cultivar resistant to Xoo.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.81-82
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• 2015

BIM has been a reliable construction project management tool to handle various kinds of construction information generated in the facility life cycle. To take these advantages, researchers have been promoted numerous studies in a residential, a commercial, and an educational facilities with a large number of on-going projects. However, despite running as the role of essential energy supplier, power plant related BIM research is relatively insufficient than others. In particular, due to the extending of the facility service period and the requirement of the complicated construction project management for 'overhaul' and 'repowering' in the power plant maintenance phase, the needs for using BIM have been increased gradually. For using BIM based maintenance, it is needed to consider an information collecting methods and necessary to develop an appropriate breakdown structure to share information. Therefore, 'EBS' is produced by reviewing the previous research related to BIM and analyzing the repair activities in the maintenance phase. Proposed 'EBS' must be useful not only a judgment between capital expenditure versus revenue expenditure but also appropriate maintenance strategies development for property management.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.3
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• pp.415-419
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• 2016

As the need for clean coal technology has grown, so has the global research and development efforts into integrated gasification combined cycle (IGCC) plants. An IGCC plant couples a gas turbine to a gasification block. Various technical and economic problems exist in designing such a system. One such problem is the difficulty in realizing economies of scale because the single-train flow capacity of commercial IGCC synthetic gas turbine plants is limited; the capacity does not exceed a net power rating of 300 MW. To address this problem, this study modeled and simulated a synthetic gas turbine with the goal of evaluating the feasibility of a 500 MW or larger IGCC plant. First, a gas turbine with the best output and efficiency was chosen for use with natural gas. The turbine was modeled using GateCycle (a simulation tool), and the integrity of the model validated by comparing the result to the design value. Next, off-design modeling was carried out for a gas turbine with synthetic gas based on its on-design model, and the result was compared with the study result of the gas turbine manufacturer. The simulation confirmed that it is possible to create a large capacity IGCC plant by undertaking the remodeling of a gas turbine designed to use natural gas into one suitable for synthetic gas.

• Journal of Applied Biological Chemistry
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• v.44 no.4
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• pp.167-172
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• 2001

A cDNA fragment encoding the chloroplastic fructose-1, 6-bisphosphatase (FBPase) was cloned via PCR from the cDNA library of pea leaves. The cloned cDNA, about 1.05 kbp without signal sequence, was introduced into a pET-28a vector for expression in E. coli strain BL21(DE3)pLysS. The recombinant FBPase was purified through $Ni^+-NTA$ affinity chromatography and characterized. Molecular mass of the monomer was about 42,000. Enzymatic activity of the purified enzyme as the native pea chloroplastic FBPase was the highest at alkaline pH (pH 9.0). The recombinant enzyme was activated by a reducing agent DTT and was insensitive to AMP. The activation energy (Ea) and Arrehenius frequency factor were 42.67 kcal/mol and $2.65{\times}10^{14}/s$, respectively, slightly higher than those of the native enzyme. $K_M$ and $V_{max}$ were $99.98{\mu}M$ and $52.9{\mu}M/min$, respectively, which were comparable with the native enzyme.

• Journal of Power System Engineering
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• v.8 no.3
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• pp.18-22
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• 2004

Boiler is one of the most important utilities providing steam to turbine in order to supply mechanical energy in thermal power plant. It is composed of thousands of tubes for high efficient heat transfer. The material for boiler tubes is used in such high temperature and pressure condition as $540^{\circ}C$, 22MPa. The boiler tube material is required to resist creep damage, fatigue cracking, and corrosion damages. 2.25%Cr-1Mo steel is used for conventional boiler tubes, and austenitenite stainless steel is used for higher temperature boiler tubes. But the temperature and pressure of steam in power plant became higher for high plant efficiency. So, the property of boiler tube material must be upgaded to fit the plant property. Several boiler tube material was developed to fit such conditions. X20CrMoV12.1 steel is also developed in 1980's and used for superheater and reheater tubes in supercritical boilers. The material has martensite microstructures which is difficult to evaluate the degradation. In this thesis, degrade the X20CrMoV12.1 steel at high temperatures in electric furnace, and evaluate hardness with Vickers hardness tester and strengths with Indentation tester.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.4
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• pp.422-426
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• 2009

Sweetpotato is one of the important starch crops, current more considered as an industrial crop rather than food because it has higher starch content (over 80% of biomass), it is used for bio resources for industrial area. In this study, we generated S598A (a mutant gene of oat phytochrome A) sweetpotato plant using Agrobacterium-transformation method. Morphological characteristics of S598A plant were compared with the wild type sweetpotato, S598A had darker green leaves, increased chlorophyll content higher than to two-fold, delayed leaf senescence, shorter plant height (60% shorter than that of the wild type), more number of leaves and petioles about 1.8-fold, shorter petiole length (30% shorter), 1.2-fold more branches and 1.6-fold thicker stem diameters. From this study, S598A plants with such phenotypic characteristics might be able to use the solar energy efficiently, to have increased tolerance to biotic and abiotic stresses and finally to increase productivity (not only starch yield but also root biomass yield). S598A sweetpotato lines are under field trials.

• Journal of Environmental Science International
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• v.18 no.6
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• pp.603-608
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• 2009

Activated sludge sewage treatment processes are difficult to be controlled because of their complex and nonlinear behaviour, however, the control of the dissolved oxygen level in the reactors plays an important role in the operation of the facility. For this reason, this study is designed to present a system which accurately measures DO, MLSS, pH and ORP in the aeration tank to alleviate situations above and provide the automatization of a sewage treatment plant (STP) using new DO control system. The automatic control systems must be guaranteed the accuracy. Therefore, the proposed automatic DO control system in this study could be commercial applications in the aeration tanks by means of operating cost analysis and user-friendly for operation and maintenance. We could get accurate data from the lab tank which has water quality checker because there was no vortex and air bubble during the measurement process. Improvement of confidence in the lab tank enabled effective and automatic operation of sewage treatment plants so that operation costs and manpower could be saved. If this result is put in place in every sewage treatment plant nationwide for practical purposes, it is estimated to cost 18.5 million dollars in installing the lab tank and to save 9.8 million dollars in management cost a year, except for cost saved by automation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.8
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• pp.51-59
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• 2013

High temperature fuel cell system, such as molten carbonate fuel cells(MCFC) and solid oxide fuel cells(SOFC), are capable of operating at MW rated power output. The power output change of high temperature fuel cell imposes the thermal and mechanical stresses on the fuel cell stack. To minimize the thermal-mechanical stresses on the stack, increases in the power output of high temperature fuel cell typically must be made at a slow rate. So, the short time interruption of high temperature fuel cell causes considerable generated energy losses. Because of the characteristic of high temperature fuel cell, we analyzed the impact of electrical fault in the fuel cell plant on other fuel cell generators in the same plant site. A various grounding configuration and voltage sag are analyzed. Finally, we presented the solution to minimize the effect of fault on other fuel cell generators.

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1315-1322
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• 2010

A membrane bioreactor (MBR) was designed using polyvinylidene fluoride(PVDF)-type hollow fiber membrane modules with a treatment capacity of 10 ton/day. A pilot plant was installed in a sewage treatment plant and was operated with an intermittent aeration method which avoids any concentration gradient of suspended solids (SS) in the MBR. For continuous operation, the pilot plant was first tested with influent (mixed liquor suspended solid:MLSS of 1000-2000 mg/L) of aeration tanks in the sewage treatment plant. The MBR was pre-treated with washing water, 10% ethanol solution, 5% NaOCl solution and finally washing water, one after another. To demonstrate the effect of the MBR on sewage treatment, compared with conventional activated sludge processes, we investigated the relationships among permeate amount (LMH), change in operation conditions, influent MLSS level and sludge production. It was found that the optimum aeration rate and suction pressure were $0.3\;m^3$/min and 30~31 cmHg, respectively. Under stable conditions in aeration, suction pressure, influent flow rate and drainage, the SS removal efficiency was more than 99.99% even when the MLSS loading rate changes. Compared with conventional activated sludge processes, the MBR was more effective in cost reduction by 27% based on permeate amount and by 51.5% on sludge production.

• 한국가스학회:학술대회논문집
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• 2005.10a
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• pp.141-145
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• 2005

DME (Di-Methyl Ether) is a new clean fuel and an environmental-friendly energy resource, also is recently increasing with an alternative interest because of the industrial use. DME has been shown to have excellent properties as a diesel fuel giving emission level better than ULEV standard. So it has been attracting considerable as an alternative diesel fuel. In this study, we carried out simulation of separation and purification process of demo plant for 101on per day DME production, which cause the effect that is important in productivity, from operation results of pilot plant for 50kg per day DME production. The liquefied stream, which was separated by gas-liquid separator after DME reactor, includes $CO_2$, DME, Methanol and $H_2O$. We established three distillation columns for separation and purification of the stream. $CO_2$ was extracted from the stream by first distillation column, DME was extracted by second column and Methanol was extracted by third column. We investigated and analyzed the effect which the actual operation variables cause in efficiency of process and optimized process, finally we got the DME of purity $100\%$.