• Journal of the Society of Disaster Information
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• v.18 no.2
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• pp.324-332
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• 2022

Purpose: In order to conduct a spontaneous ignition test in which a fire occurs in the absence of an ignition source due to the oil adsorbed on the towel. A phenomenon in which spontaneous ignition occurs when adsorbed to fibers using flaxseed oil, which is drying oil and olive oil, which is non-drying oil, is tested through an experiment. Method: After placing the sample container in the experimental device, observe the change in the central temperature of the sample, and when the central temperature rises above the set temperature and a fire occurs, it is judged as "ignition", and the experiment is stopped after checking the maximum value of the central temperature of the sample,When the central temperature of the sample was maintained similar to the set temperature, it was judged as "non-ignition" and the experiment was stopped. Result: In the towels with adsorbed flaxseed oil, the temperature in the sample container increased rapidly and combustion occurred in sheets 5, 10, and 15. Olive oil is a non-drying oil, does not ignite because it is difficult to dry because carbon is a single bond and it is difficult to bond with oxygen. Conclusion: It was confirmed that the more the amount of towel adsorbed to the drying oil, flaxseed oil, the longer the time to reach the set temperature and the occurrence of ignition.

• Proceedings of the Membrane Society of Korea Conference
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• 2001.10a
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• pp.39-50
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• 2001

The performance of membranes is governed their pore struture. Pore structures of porous materials can be determined by a number of techniques. However, The novel technique, capillary folw porometry has a number of advantages. In this technique, the sample is brought in contact with a liquid that fills the pores in the membrane spontaneously. Gas under pressure is used to force the liquid from the pores and increase gas flow. Gas flow rate measured as a function of gas pressure in wet and dry samples yield data on the largest pore size, the mean flow pore size, flow distribution and permeability. Pore characteristics of a number of membranes were measured using this technique. This technique did not require the use of any toxic material and the pressure employed was low. Capillary flow porometry is a suitable technique for measurement of the pore structure of many membranes.

• Journal of the Korean Society of Safety
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• v.14 no.4
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• pp.135-141
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• 1999

This study is an experimental study to investigate the possibility of the utilization of paper ash as the cover, liner in waste disposal landfill and other construction materials. The sample used in these tests was obtained from Daehan paper mill. A series of tests were peformed to evaluate basic properties, compaction, permeability, compressive strength, consolidation, leaching, and CBR of paper ash. In order to investigate the soil engineering properties of paper ash, the test results were compared with those obtained of fly ash. The results of unconfined compression tests show that paper ash had a larger strength than the fly ash. Also, the maximum dry unit weight of paper ash was approximately 59～76.9% less than that of the fly ash. It was found from the results of leaching test that paper ash is classified as non-detrimental general wastes according to the waste management law.

• Smart Structures and Systems
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• v.4 no.5
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• pp.549-563
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• 2008

The ability of an electroactive polymer, IPMC (Ionic Polymer Metal Composites,) to produce electric charge under mechanical deformations may be exploited for the development of next generation of energy harvesters. Two different electrode types (gold and platinum) were employed for the experiments. The sample was tested under dynamic conditions, produced through programmed shaking. In order to evaluate the potential of IPMC for dry condition, these samples were treated with ionic liquid. Three modes of mechanical deformations (bending, tension and shear) were analyzed. Experimental results clearly indicate that IPMCs are attractive applicants for energy harvesting, with inherent advantages like flexibility, low cost, negligible maintenance and virtually infinite longevity. Besides, preliminary energy harvesting model of IPMC has been formulated based upon the work of previous investigators (Newbury 2002, Newbury and Leo 2002, Lee, et al. 2005, Konyo, et al. 2004) and the simulation results reciprocate experimental results within acceptable error.

• Magazine of the Korean Society of Agricultural Engineers
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• v.14 no.2
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• pp.2661-2667
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• 1972

In the construction of earth dam, embankment, highway by filling, a compaction is to increase the density of applying pressure. By compaction interspaces between the soil graivos decrease so that density and adhesion increase but void and permeability decrease. Good compaction results in higher stablilty. The effect of the compaetion depends on a number of factors, of which the most important are soil charactesistics. Water content, and external force. In this study discussed is about sandy loam that since, with indentical force exerted and indentical compaction method, the effect of the compaction will be different due to the soil characteristics, the change of optimum moisture content and of maximum dry density by compaction yields difference in Compaction for a same sample.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.453-456
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• 1998

The electrical properties of $Si_{1-x}Ge_{x}$ samples have been investigated. The sample structures were grown by MBE (molecular geam epitaxy) with Ge mole-fraction of x=0.0, x=0.05, x=0.1, and x=0.2. To examine the influence of the thermal processing, the $O_{2}$ and N$_{2}$ process were performed at 800[.deg. C] and 900[.deg. C], respectively. After this thermal process, hall measurements have been done over a wide range of the ambient temperature between 320[.deg. K] and 10[.deg. K] to find the temperature dependence using the comparessed-He gas system. The Ge-rich layer has been formed at the $SiO_{2}$/SiGe interface and it has an effect on the hall mobility. And it has been found that hall mobility was increased by the $N_{2}$ annealing process comparing with dry oxidation process at both 800[.deg.C] and900[.deg. C].

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.12
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• pp.1271-1276
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• 2004

Two-dimensionally arrayed nanocolumn lattices were fabricated by using double-exposure laser holographic method. The hexagonal lattice was formed by rotating the sample with 60 degree while the square lattice by 90 degree before the second laser-exposure. The reactive ion etching for a typical time of 30 min using CH$_4$/H$_2$ plasma enhanced the aspect-ratio by more than 1.5 with a slight increase of the bottom width of columns. The etch-damage was observed by photoluminescence (PL) spectroscopy which was removed by the wet chemical etching using HBr/$H_2O$$_2$/$H_2O$ solution, leading into the enhanced PL intensities of the PCs.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.555-555
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• 2009

A web GIS based database system of thermophysical property of rocks in Korea is under construction. Rock samples were randomly collected over the whole country and sample spacings were generally 1 to 10 km. Thermal diffusivity, spedific heat, thermal conductivity, specific heat, density and porosity were measured on a collection of 1,560 rock samples in the laboratory. The sampled rocks were classified into igneous, metamorphic and sedimentary rock types and the variables were statistically studied. The thermal conductivity were compared with thermal diffusivity, porosity and dry density to define any correlations and the distribution of thermal conductivity is characterized by the geostatistical analysis. The optimal mapping of thermal conductivity is very useful as a practical design component for any geothermal systems.

• Fashion & Textile Research Journal
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• v.13 no.1
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• pp.130-134
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• 2011

In the study, the physical properties of the raw sample, non-circular(+ type) DTY yarn(50d level) with absorption and quick-dry function, were examined before and after being twisted(1000T/M). The results are as follows: The shrinkage of non-cricular(+type) DTY yarn(50d/36f) at $180^{\circ}$ was about 6-7% with twisted samples, but the samples without twisting went 8 to 10%. The elongation of the non-twisted and twisted samples at $180^{\circ}$ and 30-minute treatment time reached 50% and 40%, respectively. The tenacity of non-cricular(+type) DTY yarn(50d/36f) was affected less by treatment temperature in the twisted condition.

• Analytical Science and Technology
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• v.16 no.6
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• pp.509-512
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• 2003

Pretreatment method for the determination of total arsenic in seafood sample was studied. NIST SRM 1566a oyster tissue ($14.0{\pm}1.2mg\;As/kg$) as a standard arsenic compound in order to establish the decomposition method. We confirmed that the best way for pretreatment of seafoods to analyze total arsenic content precisely was $HNO_3-H_2SO_4-HCIO_4$ method by comparison of two methods which are dry ashing and wet ashing methods.