• Journal of Energy Engineering
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• v.20 no.1
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• pp.13-20
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• 2011

The high fuel flexibility of Micro Gas Turbine(MGT) has boosted their use in a wide variety of applications. Recently, the demand for biogas generated from the digestion of organic wastes and landfill as a fuel for gas turbines has increased. We researched the influence of firing landfill gas(LFG) on the performance and operating characteristics of a micro gas turbine combined heat and power system. $CH_4$ and $CO_2$ simultaneous recovery process has been developed for field plant scale to provide an isothermal, low operating cost method for carrying out the contaminants removal in Land Fill Gas(LFG) by liquid phase catalyst for introduce into the green house for the purpose of $CO_2$ rich cultivation of the plants. Methane purification and carbon dioxide stripping by muti panel autocirculation bubble lift column reactor utilizing Fe-EDTA was conducted for evaluate optimum conditions for land fill gas. Based on inflow rate of LFG as 0.207 $m^3$/min, 5.5 kg/$cm^2$, we designed reactor system for 70% $CH_4$ and 27% $CO_2$ gas introduce into MGT system with $H_2S$ 99% removal efficiency. A green house designed for four different carbon dioxide concentration from ambient air to 1500 ppm by utilizing the exhaust gas and hot water from MGT system.

• Journal of Energy Engineering
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• v.20 no.1
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• pp.36-43
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• 2011

Plant biomass has been proposed as an alternative source of petroleum-based chemical compounds. Especially, aromatic chemical compounds can be obtained from lignin by depolymerization processes because the lignin consist of complex aromatic materials. In this study, kraft lignin, the largest emitted substance among several kinds of lignin in Korea, was used as a starting material and was characterized by solid-state $^{13}C$-Muclear Magnetic Resonance($^{13}C$-NMR), Fourier Transform Infrared Spectroscopy(FT-IR), Elemental Analysis(EA). The depolymerization of kraft lignin was studied at water-phenol mixture solvent in near critical region and the experiments were conducted using a batch type reactor. The effects of water-to-phenol ratio and reaction temperature($300-400^{\circ}C$) were investigated to determine the optimum operating conditions. Additionally, the effects of formic acid as a hydrogen-donor solvent instead of $H_2$ gas were examined. The chemical species and quantities in the liquid products were analyzed using gas chromatography-mass spectroscopy(GC-MS), and solid residues(char) were analyzed using FT-IR. GC-MS analysis confirmed that the aromatic chemicals such as anisole, o-cresol(2-methylphenol), p-cresol(4-methylphenol), 2-ethylphenol, 4-ethylphenol, dibenzofuran, 3-methyl cabazole and xanthene were produced when phenol was added in the water as a co-solvent.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.101-106
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• 1979

Present studies were carried out to get a basic information for biological control of soybean rod borer, Grapholitha glycinivorella Matsumura, causing main injury in soybean cultivation in Korea. 1474 native strains were cultivated in field to evaluate the pod borer damage. Pubescence density and color, maturity group, seed coat color, aphid and general leaf damage and seed damage by pod borer were investigated, and determined among their relationships. As another basic study for ecological control of insect, 6 leading varieties were planted on different planting date with 3 levels of plant spacing, on which pod borer damage and some related agronomic characters were studied. The results obtained one summarized as follows: Average injury of soybean pod borer was $5.2\%$ ranging $0-38\%$ in 1474 strains planted on 20 May. Non-significant correlations were found between pod borer damage and pubescence density and color, while pod borer damage closely related with maturity groupand aphid damage at $5\%$ level ofttests. Most severe damage was found in green seed coast color and maturity group V. Late and sparse plantings tend to have more damages to the pod borer than those of early and dense plantings. Pod setting date and period of pod maturing seemed related with pod borer damage. Bongeui and Chungbuk-baik cultivars were resistance to soybean pod borer, while Clark and Kumkang-daerip were susceptible in field tests.

• IMMUNE NETWORK
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• v.1 no.2
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• pp.126-134
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• 2001

Background : Paeonia japonica Miyabe is a medicinal plant which has been widely used as a component of blood-building decoctions (Chinese medicinal concept : Bu-Xie). The immunopharmacological characteristics of the extract of Paeonia japonica (PJ) were investigated. Methods : The effects of fractions of PJ extract on lymphocyte proliferation were measured by $H^3$-thymidine incorporation assay. The proliferated lymphocyte subsets were analyzed in flow cytometry. The subset cell populations of spleen cells were separated by magnetic cell separation system, and their proliferation by the extract were investigated. The effect of the extract on antibody production was determined in mice challenged with sheep red blood cells (SRBC) using hemolytic plaque forming cell assay. Results : Spleen cells were proliferated by water extract of PJ. Polysaccharide fraction (PJ-P) of the extract was most active in the proliferation. It was found in flow cytometry that the lymphocyte subset proliferated by PJ-P was B cell population. Among the separated subset cell populations, T cell-depleted cell population and macrophage-depleted cell population were most proliferated by PJ-P. However, positively selected populations of B cells and T cells were not proliferated by PJ-P. These results indicate that B cell proliferation by PJ-P may require the assistance of macrophages or T cells. These results suggest that firstly PJ-P may stimulate macrophages or T cells, and then B cells are activated. The number of antibody-secreting cells was increased by administration of PJ-P in mice immunized with SRBC as a T-dependent antigen. Conclusion : These results suggest that macrophages and accessory cells are directly activated by PJ-P and then helper T cells and B cells are indirectly activated. As the results, immune responses might be coordinately improved. In conclusion, PJ-P, a polysaccharide of P. japonica, may be a characteristic immunostimulator, which is analogous to polysaccharides such as lentinan, PSK and ginsan.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.186-190
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• 2014

Nuclear Power Plants require the control ability of chemical condition (pH) because pH control during transient accident such as LOCA makes an able the fission product removal capability to be maintained, stress corrosion cracking of stainless steel equipment to be prevented and the production of hydrogen by aluminum and zinc to be minimized. An NPP is designed to control the pH of containment spray and sump coolant using the spray additives 30% NaOH in the event of loss of coolant accident. In this paper, the pH of sump coolant of an NPP during LOCA was analyzed and the fission products removal constant and decontamination factor were calculated according to Standard Review Plan 6.5.2 related to spray chemical conditions of pH. The calculated pH value of recirculation mode using the computer code corresponds to 8.09~9.67, which meets the chemical environment regulation requirements. The fission product removal capability caused by containment spray system is performed to provide input to radiation analysis.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.1
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• pp.49-56
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• 2005

Many different kinds of radwastes are discharged from the nuclear power plants, and $^{129}$I is included in these radwastes. Recovery test of $^{129}$I was evaluated for different radwastes(dry active waste, sludge, spent resin and simulated evaporator bottom). Recovery of $^{129}$I for dry active waste by acid leaching with $1.8\%$ NaClO was $74.3\%$$(RSD,\;2.2\%)$ and l291 for spent rein by alkali fusion method with KOH as a flux agent was $87.7\%$$(RSD,\;0.9\%$), respectively. iodide in simulated evaporator bottom containing a high concentration of borate was adsorbed with anion exchange resin at pH 7 phosphate buffer solution. Recovery of $^{129}$I for anion exchange resin was $92.5\%$ and not affected up to 1,200 $\mu$g/mL $H_3BO)3$(as a Boron). Recovery of $^{129}$I for the spent resin from nuclear power plant was $87.2\%$ $(RSD,\;1.2\%)$.

• The Journal of Engineering Geology
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• v.19 no.1
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• pp.63-70
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• 2009

The optical fiber cable acting as a sensor was embedded in the underground research tunnel and portal area in order to monitor their stability and the spatial temperature variation. This system includes two types of sensing function to monitor the distributed strain and temperature along the line, where sensor cable is installed, not a point sensing. According to the results of one year monitoring around the KURT, there is no significant displacement or movement at the tunnel wall and portal slope. However, it would be able to aware of some phenomena as an advance notice at the tunnel wall which indicates the fracturing in rockmass and shotcrete fragmentation before rock falls accidently as well as movement of earth slope. The measurement resolution for rock mass displacement is 1 mm per 1 m and it covers 30 km length with every 1m interval in minimum. In temperature, the cable measures the range of $-160{\sim}600^{\circ}C$ with $0.01^{\circ}C$ resolution according to the cable types. This means that it would be applicable to monitoring system for the safe operation of various kinds of facilities having static and/or dynamic characteristics, such as chemical plant, pipeline, rail, huge building, long and slim structures, bridge, subway and marine vessel. etc.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.4
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• pp.429-437
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• 2006

To establish the efficient treatment technology of chemical cleaning wastewater from power plant, several AOPs($UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation) were investigated. Treatment efficiencies and the electrical energy requirements based on the EE/O parameter(the electrical energy, required per order of pollutant removal in $1m^3$ wastewater) were evaluated. TOC removal efficiencies of $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation at the optimum conditions were 95.5%, 92.3%, 91.5%, respectively. The electrical energy requirements of $UV/H_2O_2,\;UV/TiO_2/H_2O_2$, Photo-Fenton oxidation were $11.26kWh/m^3,\;3.85kWh/m^3,\;0.799kWh/m^3$, respectively. From these results, it could be concluded that all of the three oxidation processes were effective for the degradation of citric acid. Considering the treatment efficiency and economical aspect, photo-Fenton oxidation was the most efficient treatment process among the three processes tested.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.193-200
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• 2005

[ $^{14}C$ ] and $^{3}H$ in the evaporator bottom (EB) discharged from the Nuclear power plant (NPP) were extracted simultaneously into a gaseous $^{14}CO_{2}$ and liquefied HTO by using the chemical oxidation, which is the method to oxidize samples completely using potassium persulfate and sulfuric acid. The extracted $^{14}C$ and $^{3}H$ were counted by the liquid scintillation counter (LSC) after the quench correction. To examine the recovery of $^{14}C$ using the radioactive standards, $Na_{2}^{14}CO_{3}$, $^{14}C-alcohol$, and $^{14}C-toluene$ as $^{14}C$, and HTO as $^{3}H$ were used. Also, the most suitable method for oxidizing $^{14}C-toluene$, which is difficult to be oxidized, was investigated through FT-IR spectra according to the concentration of sulfuric acid. With the identical method, $^{14}C$ and $^{3}H$ in the EB generated in the NPP were assayed in the range of $8.35{\sim}l.38{\times}10^3$ Bq/g and $2.46{\times}10^2{\sim}1.40{\times}10^4$ Bq/g, respectively.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.705-711
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• 2008

In case of the domestic condition, as the initiating from Sumjin River Dam, total 14 units of multipurpose dams had been constructed in 1965 for the roles of flood control, waterpower generation, irrigation, water supply, industrial water supply. In the case of such multipurpose dam, it produces electric energy by converting the potential energy utilizing its head and quantity of the water into kinetic energy. However, in this process, since during the time when the turbine connected to the hydraulic turbine dynamo revolves and there occurs a loud noise, it brings the physical, mental bad influences to those people also a decline of an effective working efficiency. On such point of view, after selection of various 16 measurement points, this study has measured and analyzed the travelling characteristics of noise generated at the hydraulic turbine dynamo in Daechung Dam, and also has evaluated the degree of indoor noise using the evaluation index such as PSIL, NC. As the result of noise-evaluation, in case of Daechung Dam, since the noise damage grade appears very seriously at various spaces, it is considering that its soundproof measure would be necessitated keenly. Also, it is considered that such data could be utilized as the valuable material hereafter for establishment of an efficient noise-reduction countermeasure and a comfortable working environment for the hydraulic turbine dynamo plant.