• Journal of the Korean Society of Safety
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• 제20권4호
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• pp.171-179
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• 2005

It is essential to understand the role of wall lining materials when they are exposed to a fire from an ignition source. Full-scale test methods permit an assessment of the performance of a wall lining material. Fire growth models have been developed due to the costly expense associated with full-scale testing. The models require heat flux maps from the ignition burner flame as input data. Work to date was impeded by a lack of detailed spatial characterization of the heat flux maps due to the use of limited instrumentation. To increase the power of fire modeling, accurate and detailed heat flux maps from the ignition burner are essential. High level spatial resolution for surface temperature can be provided from an infrared camera. The objective of this study was to develop a heat flux mapping procedure for a room test burner flame to a wall configuration with surface temperature information taken from an infrared camera. A prototype experiment was performed using the ISO 9705 test burner to demonstrate the developed heat flux mapping procedure. The results of the experiment allow the heat flux and spatial resolutions of the method to be determined and compared to the methods currently available.

• Korean Journal of Oriental Medicine
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• 제12권1호
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• pp.23-38
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• 2006

The taxonomic list of specific features in external and internal shape and the pattern analysis of Aconitum carmichalei $D_{EBX}$ as the original plant of Aconiti Lateralis Radix Preparata and Aconitum cliiare Dc as the original plant of Aconiti Ciliare Tuber are as follows. 1. Aconitum carmichalei $D_{EBX}$ has tri-palmately parted leaves, petiole in lower leaves, and its ovary has short hair. Whereas Aconitum cliare Dc has $3{\sim}4$ parted leaves, long petiole, and its ovary has not hair. 2. Aconitum carmichalei $D_{EBX}$ has cylinder shape is relatively small in length and diameter, is greyish brown blacky brown in outer surface, greyish $white{\sim}dark$ gray in section. 3. According to the collection place, there is a remarkable difference in the physical shape of herbal states. Aconiti Lateralis Radix Preparate(medicated in Korea) is more transparent blacky brown color than Aconiti Lateralis Fadix Preparata(medicated in Chian). Also Black Aconi Radix(墨附片) has exodermis and White Aconi Radix(白附片) has not. 4. The internal characteristics entirely correspond to in internal shape described in the literatures, Only it is possible to discriminate between black Aconi Radix(墨附片) and White Aconi Radix(白附片) by the existence of cork layer. The classification between Aconiti Lateralis Radix Preparata and Aconiti Ciliare Tuber makes entirely Tuber makes entirely remarkable difference in the physical shape of cambium layer Namely, in shape of cambium layer the kinds of Aconiti lateralis Radix Prepala has horn-like shape and the kinds of Aconiti Ciliare Tuber has circle-like shape. 5. In the peak of examination substance in comparison to Rt of the index material diterpene alkaloid mesaconitine, aconitine, hypaconitine chromatogram Aconiti Ciliare Tuber is higher than in Aconiti Lateralis Radix Preparata This explain that the component changes after the process of medicine. 6. In the Content of mesaconitine, aconitine and hypaconitime Aconiti Ciliare Tuber is higher than Aconiti Lateralis Radix Preparata. 7. In Aconiti Lateralis Radix Preparata, aconitine, hypaconitine and mesaconitine each appears in Rf 0.46, 0.54, 0.32. But except Aconiti Ciliare Tuber the band does not appear. For the future, such results will be used as the basic source of additional research, and a far-reaching comparative study is needed to distinguish between many kinds of same genus-degree of relatedness.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제3권1호
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• pp.49-57
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• 2002

The possibility of a transmission noise reduction of piezoelectric smart panels using piezoelectric shunt damping is experimentally studied. Piezoelectric smart panel is basically a plate structure on which piezoelectric patch with shunt circuits is mounted and sound absorbing materials are bonded on the surface of the structure. Sound absorbing materials can absorb the sound transmitted at mid frequency region effectively while the use of piezoelectric shunt damping can reduce the transmission at resonance frequencies of the panel structure. To be able to reduce the sound transmission at low panel resonances, piezoelectric damping using the measured electrical impedance model is adopted. Resonant shunt circuit for piezoelectric shunt damping is composed of register and inductor in series, and they are determined by maximizing the dissipated energy throughout the circuit. The transmitted noise reduction performance of smart panels is investigated using an acoustic tunnel. The tunnel is a tube with square crosses section and a loud-speaker is mounted at one side of the tube as a sound source. Panels are mounted in the middle of the tunnel and the transmitted sound pressure across panels is measured. Noise reduction performance of a smart panels possessing absorbing material and/or air gap shows a good result at mid frequency region but little effect in the resonance frequency. By enabling the piezoelectric shunt damping, noise reduction of 10dB, 8dB is achieved at the resonance frequencise as well. Piezoelectric smart panels incorporating passive method and piezoelectric shunt damping are a promising technology for noise reduction in a broadband frequency.

• The Korean Journal of Quaternary Research
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• 제18권1호통권22호
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• pp.1-20
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• 2004

A geoscientific research was performed on 12 samples of comb-pattern potteries which were excavated at Daecheonri neolithic site, Korea. The texture and compositions of 12 potteries and surrounding metrix of soil and rocks were compared with the help of petrographic microscope, XRD and REE data. As to the manufacturing techniques thick potteries are caused by the amount and number of coarse grains which are assumed to be added shards when their distributional pattern are considered. DC1, DC3, DC 7 and DC11 samples have clearly oriented textures, and the orientation of vesicles in DC3 and DC11 samples arranged in the same direction with those on the pottery surface. This indicates the use potter's wheel technique in manufacturing potteries. Burning temperature is assumed over $800^{/circ}C$, particularly under reduction environment. As to the source, raw materials of pottery matrix are derived from the bottom of excavation site, or in an extracted outcrop of the northwestern foothill from site, while the shard materials are very similar with those extracted from sandy loams near sites. Finally any use pattern of pottery may control the pottery thickness, shard addition, and matrix selection.

• Resources Recycling
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• 제18권2호
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• pp.39-50
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• 2009

Portland cement production is under critical review due to high amount of $CO_2$ gas released to the atmosphere. Attempts to increase the utilization of fly ash, a by-products from thermal power plant to partially replace the cement in concrete are gathering momentum. But most of fly ash is currently dumped in landfills, thus creating a threat to the environment. Many researches on alkali-activated concrete that does not need the presence of cement as a binder have been carried out recently. Instead, the source of material such as fly ash, that are rich in Silicon(Si) and Aluminium(Al), are activated by alkaline liquids to produce the binder. Hence concrete with no cement is effective in the reduction of $CO_2$ gas. In this study, we investigated the influence of the compressive strength of mortar on alkaline activator and curing condition in order to develop cementless fly ash based alkali-activated concrete. In view of the results, we found out that it was possible for us to make alkali-activated mortar with 70MPa at the age of 28days by using alkaline activator manufactured as 1:1 the mass ratio of 9M NaOH and sodium silicate and applying the atmospheric curing after high temperature at $60^{\circ}C$ for 48hours.

• Journal of the Korean Institute of Gas
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• 제12권2호
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• pp.38-41
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• 2008

In this research, we propose a new method for tracking the release rate using the concentration data obtained from the sensor. We used a sensor network that has already been set surrounding the area where hazardous gas releases can occur. From the real-time sensor data, we detected and analyzed releases of harmful materials and their concentrations. Based on the results, the release rate is estimated using the neural network. This model consists of 14 input variables (sensor data, material properties, process information, meteorological conditions) and one output (release rate). The dispersion model then performs the simulation of the expected dispersion consequence by combining the sensor data, GIS data and the diagnostic result of the source term. The result of this study will improve the safety-concerns of residents living next to storage facilities containing hazardous materials by providing the enhanced emergency response plan and monitoring system for toxic gas releases.

• Korean Journal of Soil Science and Fertilizer
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• 제35권6호
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• pp.327-334
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• 2002

Method of besoil analysis were difficult to be applied universally since the use and the source material of bedsoils are diverse from country to country. Korean Standard Methods for Bedsoil Analysis was developed to measure the particle and bulk density. Fifty-three samples for horticultural bedsoil and nine samples for paddy rice bedsoil in the current market were collected. Particle density was measured by electrical pyconometer with He gas, and bulk density by the sandbox method, free fall method, plunger compaction method, free fall and plunger method, and sample weight compaction method. While the use of glass pycnometer which measures particle density to fill blank space with water was inappropriate due to floating organic and calcined inorganic materials in the water, the electrical pycnometer with gas type was suitable considering speed and accuracy. For bulk density, the sandbox method recommended as European Standard Method was more reasonable in principle than other methods. However, this method requires expensive apparatus and intricate process. Plunger compaction method was proposed as standard method, since it had higher consistence with the sandbox method than other methods, as well as an advantage of easy and prompt measurement. Particle density of bedsoil ranged $1.48{\sim}2.67Mg\;m^{-3}$(mean $1.93Mg\;m^{-3}$) for horticultural bedsoil and $2.33{\sim}2.67Mg\;m^{-3}$ (mean $2.43Mg\;m^{-3}$) for paddy rice bedsoil by the electrical pycnometer with He gas. Bulk density of bedsoil ranged $0.11{\sim}0.40Mg\;m^{-3}$ (mean $0.22Mg\;m^{-3}$) for horticultural bedsoil and $0.84{\sim}1.26Mg\;m^{-3}$(mean $1.01Mg\;m^{-3}$) for paddy rice bedsoil by plunger compaction method.

• Journal of Sericultural and Entomological Science
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• 제49권2호
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• pp.43-46
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• 2007

Analysis of general ingredients and amino acid content in dried silkworm feces which were extracted with hot water, EtOH, MeOH for developing new income source of rearing farm, seeking high additive value material and industrialization of silkworm feces. In the analysis of general ingredient content by extracting solution, raw protein and ash contents were increased with MeOH, EtOH, hot water. And raw fat showed higher contents by the order of EtOH > MeOH > hot water. The inorganic matter content showed a little difference among collection times of silkworm feces. Hot water was most effective extracting solution for total amino acid, and no significant difference between EtOH and MeOH. According to the time, there were no significant difference in amino acid contents. When extracted with hot water, Glu content was highest content and order of others is Asp > Gly > Ala > Leu > Thr > Ser among 18 amino acids.

• Journal of the Mineralogical Society of Korea
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• 제19권1호통권47호
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• pp.7-14
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• 2006

Melting slag generated from the lots of municipal incineration ash, which causes the one of big urban problems in modern industrial society, was used as starting material for the hydrothermal synthesis of zeolite. P-type zeolite has been successfully synthesized by the combined process of both 'hydrogelation' and 'clay conversion' method. Commercial sodium silicate was used as Si source, and $NaAlO_2$ was prepared by the reaction in a $Na_{2}O/Al_{2}O_{3}$ molar ratio of 1.2. The optimum conditions for zeolite synthesis was found to be the $SiO_{2}/Al_{2}O_{3}$ ratio in the 3.2 and 4.2 range, the $H_{2}O/Na_{2}O$ ratio in the 70.7 and 80.0 range, and more than 15-hour reaction time at $80^{\circ}C$, In the synthesized zeolite, inhomogeneous melting slag particles were disappeared and homogeneous P-type zeolite crystal was grown. The cation exchange capacity of the synthesized zeolite was determined to be approx. 240 cmol/kg.

• Journal of Marine Bioscience and Biotechnology
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• 제1권2호
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• pp.63-70
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• 2006

Natural product compounds are the source of numerous therapeutic agents. The marine environment produces natural products from a variety of structural classes exhibiting activity against numerous disease targets including anticancer agents. Among these, pectenotoxin-2 (PTX-2), which was first identified as a cytotoxic entity in marine sponges, which depolymerizes actin filaments, was found to be highly effective and more potent to activate an intrinsic pathway of apoptosis in p53-deficient tumor cells compared to those with functional p53 both in vitro and in vivo. However, the anti-proliferative mechanism of the compound at non-cytotoxic concentrations has not yet been explored. In the current study, we sought to investigate anti-proliferation and apoptosis of PTX-2 against U937 human leukemic cells and its underlying molecular mechanism. Exposure of U937 cells to PTX-2 resulted in growth inhibition and induction of apoptosis in dose- and time-dependent manner as measured by MTT assay, fluorescent microscopy and flow cytometric analysis. The anti-proliferative effect of PTX-2 was associated with a marked increase in the expression of cyclin-dependent kinase p21 (WAF1/CIP1) mRNA which was tumor suppressor p53-independent. The increase in apoptosis was connected with a time-dependent down-regulation of anti-apoptotic Bcl-XL and inhibitor of apoptosis proteins (IAPs) family such as XIAP and cIAP-2. Though additional studies are needed, these findings suggested that PTX-2-induced inhibition of U937 cells was associated with the induction of apoptotic cell death and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of PTX-2.