• Journal of Power System Engineering
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• v.5 no.1
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• pp.11-20
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• 2001

Super-critical type steam power plant, which operates with steam pressure above the super-critical point, has a good reputation recently and is adopted as a new standard of the Korean Electric Power Corporation. The reason for the good reputation lies in it's superior power efficiency. However, the field data of the new power plant for the verification of it's performance are still insufficient, and more empirical data are needed to acquire technologies on the effective operation of it. In this study, the authors analyzed the field test data on power efficiencies got in a super-critical type steam power plant, and evaluated the excellency of the new plant by comparing the efficiency data with the one got in a conventional sub-critical type steam power plant.

• Journal of IKEEE
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• v.23 no.2
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• pp.350-357
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• 2019

We analyzed the system efficiency of small solar power plants with 80% of total solar power plants. The data of the solar power plant with installed capacity of 100kW was collected and the correlation of the ESS efficiency according to the capacity of the PCS and the battery of each power plant was deduced. As a result, the higher the C-rate value affecting the discharge rate of the battery, The discharge efficiency of the plasma display panel is increased.

• Plant Resources
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• v.1 no.1
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• pp.53-59
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• 1998

Laboratory experiments for the removal efficiency of heavy metals in land application of sludge, the accumulation and translocation of heavy metals in x plants after transplanting, and the responses of Minari growth with different ratio of land application of sludge were conducted to determine the potential ability of bioremediation with Minari plants. The removal rate and translocation of copper. zinc. lead. and cadmium in soil and plants were compared after transplanting the Minari plants to soil treated with different ratio of sludge. The removal efficiency of heavy metals in soil incorporated with sludge was different with application ratio, but increased with growing periods of Minari plants. The removal efficiency of Cu, Zn, Pb, and Cd ranged from 67 to 74% from 51% to 63%, from 37% to 71%. and from 15% to 25% after 45 days of transplanting. respectively. The amount removed the copper value. 65.9 mg/kg, observed to be highest in soil incorporated 3% sludge after 45 days. The translocation of Cu. Zn. Pb. and Cd from shoots to roots ranged from 18 to 53%, from 17 to 32%, from 14 to 49%, and from 23 to 38% over growing periods. respectively. In plant responses it appeared to be inhibited the plant growth in the treatment compared with the control at early stage of growth. However, the fresh weights of Minari plant increased from 12.5 to 62.5% in the sludge application after 45 days relative to the control. Therefore the Minari might play a useful role in bioremediation of Cu, Zn, Pb, and Cd in the land application of sludge.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.378-387
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• 2000

A rice mill plant with a capacity of 2.5 ton/hr was constructed with automated facilities at Chonnam National University. A simulation model was developed with SLAM SYSTEM for evaluating and improving the rice mill plant. The developed model was validated in the views of hulling efficiency, milling efficiency, milled rice recovery, other materials produced, and bottlenecks in the processes. The results of hulling efficiency, milling efficiency, milled rice recovery in the simulation were, respectively, 81.1%, 89.5%, and 73.1%, while those of the actual mill plant were 81.5%, 90.2%, and 73.5%. The simulation results including the productivity of other materials(chaff, bran, broken rice, stone, etc) produced in the processes were almost similar with those of the actual process. In the simulation the bottlenecks were found out in the processes of separating brown rice and of sorting colored rice. These phenomenon also appeared in the actual process. It needed to increase the hourly capacity of the brown rice separator and the rice color sorter. As the developed model could well express the automated rice mill plant, it could be used for designing and improving rice mill plants. In addition, an alternative model needed to be developed for the system control more accurately and for increasing the rice quality.

• Journal of IKEEE
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• v.22 no.4
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• pp.959-964
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• 2018

In this study, a study is conducted on a monitoring system that can control the environment of plants using sensors in conjunction with the LED light system and the plant growth control system. To verify the performance of the developed plant growth system, an experiment was conducted on the characteristics of energy efficiency, data transmission rate, and light volume control. The experiment resulted in a satisfactory result by controlling more than 80% energy efficiency, 1Mb/sec wireless communication speed, and 5 levels of optical control. The proposed system can be applied to LED plant facilities and will contribute to the automation of agriculture by organizing an automated system for production efficiency and labor cost reduction for future commercialization.

• Plant Journal
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• v.9 no.3
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• pp.43-47
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• 2013

Even if an expert who has majored energy engineering, it is a difficult concept to understand power output optimization and power efficiency optimization. In this study a diagram applying thermodynamic state value as specific exergy and exergy ratio was developed. Although general peoples who did not major energy engineering can be easily understand the concept of power output optimization and power efficiency through the developed diagram. A represented property that can identify the performance of power plant is the main steam temperature and pressure. At the developed diagram the maximum power output line and maximum power efficiency line are shown according to the temperature and pressure of main steam. Therefore we can identify how much a power plant approach to maximum power output and maximum power efficiency.

• International Journal of Fluid Machinery and Systems
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• v.3 no.4
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• pp.379-385
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• 2010

We developed a high-efficiency, wide-operating-range centrifugal blower stage to meet the demand for reduced total energy-consumption in sewage treatment plants. We improved the efficiency of the two-dimensional impeller using a shape optimization tool and one-dimensional performance prediction tool. A limit of the throat deceleration ratio was set to maintain the stall-margin of the impeller. The low solidity vaned diffuser and return channel were designed using a sensitivity analysis with orthogonal arrays and three-dimensional steady flow simulations. The low solidity diffuser was designed in order to improve the performance in the low-flow-rate region. The return channel was designed so that the total pressure loss in the return channel was minimized. Model tests of both the conventional and optimized blower stages were carried out, and the efficiency and operating range of both stages were compared. The optimized blower stage improved in stage efficiency by 3% and in operating range by 5% compared with the conventional blower stage.

• Journal of Korea Society of Waste Management
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• v.35 no.7
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• pp.600-605
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• 2018

In this study, the combustion characteristics were investigated based on the biodrying solid recovered fuel (SRF) in a 5 Ton/day scale combustion boiler. The composition of the combustion gas containing the biodrying SRF was analyzed, the particulate matter, and its HCl content was determined with the air pollutant process test method. Mass balance, carbon balance, and combustion efficiency were calculated according to the equivalence ratio (ER) method; the energy recovery efficiency of the combustion boiler was also analyzed. The overall combustion efficiency of the biodrying SRF was 97.3 % and the energy recovery efficiency was 80.2%.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.867-871
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• 2001

The main reason for reviewing the condensate water return system in the auxiliary steam system is to obtain the thermal high efficiency of the power plant and thus save the fossil energy in power plant. This study intends to analyze the thermal efficiency of the power plant and predict the increasing in the generator output by the return system reformation of auxiliary steam line in the thermal power plant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.4
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• pp.349-353
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• 2004

Mature embryo and leaf base segment of Korean oat were used as materials in an experiment to check plant regeneration efficiency. MS media supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D), kinetin, and picloram were used for callus induction from mature embryos and leaf base segments. Three mg/l of 2,4­D and 3 mg/l of picloram in callus induction medium showed high frequency for plant regeneration from mature embryos. Leaf base segments were transferred to callus induction medium and incubated at $25^{\circ}C$ in 16/8 hr light/dark cycle for 3 weeks. Callus induction from leaf base segments of Malgwiri showed high efficiency in medium containing 3 mg/l of 2,4-D and 1 mg/l of kinetin $(91.8\%)$. In case of Samhangwiri, the combinations of phytohormones did not show significant difference. Regeneration from leaf base segments showed high frequency in shoot medium containing 1 mg/l of antiauxin, tri-iodobenzoic acid (TIBA) and 1 mg/l of 6-benzyladenine (BA). Calli induced from leaf base segments of Samhangwiri and Malgwiri in media containing 3 mg/l of 2,4-D and 3 mg/l of picloram showed high regeneration frequency. It appears that the callus initiation medium may be an important factor for subsequent plant regeneration.