• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.266-269
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• 2005

This study targeted methane production and decrease of organic materials concentration by high temperature anaerobic digestion of food waste. A anaerobic reactor with circulation was employed and the operation condition as follows: high temperature of $45{\pm}2,$ 0.6 $kg-VS/m^3/d,$ HRT of 70 days, pH of $6.8{\sim}7.2$. The CODcr removal rate of $75%{\sim}85%$ with effluent of $14,000{\sim}19,000$ mg/L in case of influent of $75,000{\sim}95,000$ mg/L showed. In influent TS(Total Solid) and VS(Volatile Solid) concentration of $2.94%{\sim}5.09%,$ and $2.98{\sim}5.01%,$ the effluent concentration was $0.65{\sim}1.1%$ and $0.6%{\sim}0.8%,$ respectively. 0.28 $m^3-CH_4$ / kg-VS was averagely obtained in the system.

• Journal of Soil and Groundwater Environment
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• v.11 no.4
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• pp.33-40
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• 2006

Residual pesticides discharged from diffuse sources at agricultural area in association with suspended solid will be settled at downstream, and may degrade surface water quality. This research studied dechlorination kinetic of atrazine, one of triazine-category herbicide, using zero-valent iron (ZVI) in sediment. It can be observed from the experiments that buffer capacity of sediment helped pH maintained beutral, resulted in continuous dechlorination. Sediments were spiked with atrazine at 10, 30, and 50 mg atrazine/L of total sediment for batch experiments. Dechlorination constants were $1.38x10^{-1}/d$ for the initial concentration of 10 mg/L, $1.29x10^{-l}/d$ for 30 mg/L, and $7.43x10^{-2}/d$ for 50 mg/L while dechlorination constants of initial concentration of 50 mg/L without ZVI adding were estimated as $3.05x10^{-2}/d. Half lifes atrazine by ZVI were estimated as 5.03 d fur 10 mg/L, 5.38 d for 30 mg/L, and 9.33 d for 50 mg/L, respectively.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.42 no.1
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• pp.1-11
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• 2005

Several Solid Freeform Fabrication Systems(SFFS) are commercialized in a few companies for rapid prototyping. However, they have many technical problems including the limitation of applicable materials. A new method of agile prototyping is required for the recent manufacturing environments of multi-item and small quantity production. The objectives of this paper include the development of a novel method of SFFS, the CAFL/sup VM/(Computer Aided Fabrication of Lamination for Various Material), and the manufacture of the various material samples for the certification of the proposed system and the creation of new application areas. For these objectives, the technologies for a highly accurate robot path control, the optimization of support structure, CAD modeling, adaptive slicing was implemented. However, there is an important problem with the conventional 2D lamination method. That is the inaccuracy of 3D model surface, which is caused by the stair-type surface generated in virtue of vertical 2D cutting. In this paper, We design the new control algorithm that guarantees the constant speed, precise positioning and tangential cutting on the 5DOF SFFS. We develop the tangential cutting algorithm to be controlled with constant speed and successfully implemented in the 5DOF CAFL/sup VM/ system developed in this paper. Finally, this paper confirms its high-performance through the experimental results from the application into CAFL/sup VM/ system.

• The Korean Journal of Ceramics
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• v.6 no.2
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• pp.120-123
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• 2000

The geopolymer technique may be a future-oriented technology for saving energies and resources. This technique requires 3 fundamental elements so-called filler, hardener and geopolymer liquor being generally an alkaline silicate solution. Quartz powder, water quenched granulated blast furnace slag and sodium silicate solution prepared from $Na_2O\cdot2SiO_2$were chosen for these three elements. After mixing these starting materials in appropriate proportions, monoliths were prepared by casting at room temperature. Strength tests showed the following results for 28d age speciment: 7.9-12.7 MPa in flexural strength and 20.2-32.8 MPa in compressive strength, depending on geopolymer liquor/solid ratio, P/S and fineness of the quartz powders used.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.574-576
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• 2001

This paper deals with High Temperature Superconducting (HTS) Motor, which have two characteristics: the HTS magnet with iron plates as field coil, and the solid nitrogen $(SN_2)$ as a cryogen. The HTS magnet has iron plates to achieve the maximum current-carrying capacity and the simple shape that can easily be wound and jointed. The HTS magnet with iron plates, magnet optimized current distribution, and initial magnet are presented through 3 Dimensional Finite Element Analysis (3D FEA), manufacturing and testing these magnets. And, it is employed $SN_2$ for keep the operating temperature of HTS synchronous motor. To make the liquid nitrogen $(LN_2)$ of $SN_2$, Gas helium (GHe) passes into the heat exchanger and cools its own temperature. Two types of heat exchangers are designed and manufactured to make the $SN_2$, and each of the temperature characteristics is compared.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.968-971
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• 2003

Due to a low efficiency of phosphor with large Stoke shift in Vacuum Ultra Violet (VUV) excitation environment, new PDP phosphors which can be excited in UV excitation environment need to be developed. In this study, $Zn_2SiO_4:Tb$ phosphor was synthesized by solid-state reaction method at $1300^{\circ}C$ with varying Tb concentration, and its cross relaxation effect was observed by Photoluminescence (PL) measurement. In order to decrease $^5D_3{\to}7F_j$ transition with blue emission in $Zn_2SiO_4:Tb$ phosphor, Dy, co-activator element, was added to $Zn_2SiO_4:Tb$ phosphor. In 254nm excitation environment, broad-emission peak was observed around 524nm, green emission.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1243-1249
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• 2006

Volatile flavor compounds in commercial crab-like flavorants were compared by mean of solid phase microextraction(SPME) and liquid continuous extraction (LLCE)/GC/MSD methods. A total of 86 volatile flavor compounds were detected. Of these, 71 were positively identified consisting mainly of sulfur-containing compounds (13), aldehydes (3), ketones (2), esters (26), alcohols (5), aromatic compounds (3), terpenes (8), acids (2) and miscellaneous compounds (9). SPME method was more effective than LLCE method in detection of volatile components in commercial crab-like flavorants. Eight S-, N-containing compounds such as dimethyl sulfide, dimethyl disulfide, dipropyl disulfide, 3-(methylthio)propyl acetate, 3-(methylthio) propanal, 3-(methylthio) propanol, 2-methyl-3-(methylthio) pyrazine and 2-methyl-5-(methylthio) pyrazine, 8 esters such as styrallyl acetate, ethyl acetate, isoamyl acetate, benzyl acetate, ethyl pentanoate, butyl pentanoate, isoamyl pentanoate and furfuryl acetate were considered as major components in crab-like flavorants.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.5
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• pp.660-664
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• 2003

An attempt was made to evaluate the effects of total mixed rations (TMR) containing 17.5% forage neutral detergent fiber (NDF) from paragrass, paragrass+cassava chips and corn silages on the performance of dairy cows in the tropics. Experimental dietary treatments contained a similar content of total NDF, total non-fiber carbohydrates, crude protein and energy. Maximum and minimum temperature humidity index during the experimental period were 79.1-80.6 and 66.8-68.6, respectively. Among silage sources, there were no differences (p>0.05) in concentrations of acetic and propionic acids and butyric acid was undetectable. Concentration of lactic acid was higher (p<0.01) in corn silage but its pH was lower (p<0.01) than in paragrass and paragrass+cassava silages. Dairy cows on TMR containing corn silage not only gained more weight (161 and 46 vs. -189 g/d) but also consumed more feed (18.47, 15.84 and 14.49 kg/d), and produced more milk (23.89, 22.03 and 20.83 kg/d), 4% fat corrected milk (25.47, 24.05 and 22.02 kg/d), solids-not-fat (1.99, 18.3 and 1.73 kg/d) and total solid (3.10, 2.85 and 2.64 kg/d) compared with those on TMR containing paragrass+cassava and paragrass silages, respectively (p<0.01). Dairy cows on TMR containing paragrass+cassava silage were better in these respects (p<0.01). These results suggest that in formulating diets on an equal NDF basis for different forage qualities, diets higher in forage quality can stimulate higher DMI for dairy cows in the tropics and thus improve productivity.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.664-670
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• 2018

In modern society, CCTV, which is the eye of surveillance, is being used to collect image data in various ways in daily life. CCTV is used not only for security, surveillance, and crime prevention but also in many fields such as automobile and black box. In this paper, we have developed a STM32F407 ARM chip based camera system for various applications. In order to develop camera system, modeling of camera system based on 3D structure was carried out in SolidWorks environment. The PCB board design was developed to extract the PCB parts from the camera system modeling files into iges files, convert them from the Altium Designer tool into 3D and 2D boards, After designing the camera system circuit and PCB, we have been studying the implementation of the stable system by using TRM (Thermal Risk Management) tool to cope with the heat simulation generated on the board.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.47-52
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• 2003

Anthers from several lines of carrot (Daucus carota L.) were plated on the semi-solid B$_{5}$, basal medium supplemented with 2,4-D and NAA at two concentrations, 1.0 and 2.0 mg/L plus 0.2 mg/L BAP (benzylaminop-urine). Anthers of the most lines on the B$_{5}$ basal medium with 2,4-D showed higher percentages of callus formation than those with NAA. Particularly, in line 45477, highest percentages of callus formation (50%) were observed on B$_{5}$ medium with 1.0 mg/L 2,4-D plus 0.2 mg/L BAP. With 1.0 mg/L 2,4-D, two months was sufficient for initiation of callus development. Calli were regenerated into plantlets through embryogenesis onto regeneration medium without any growth regulators. When callus showing yellowish and soft structure was cultured, it yielded green plants at high regeneration rates, The response of anthers in callus induction and plant regeneration was different among lines investigated. Optimal callus induction and plant regeneration could be obtained through manipulating the concentration of growth regulators. Plantlets after transfer to perlite were grown successfully in greenhouse conditions. Anther culture of carrot will be used as a useful breeding tool in future.