• Journal of the Korean Society for Library and Information Science
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• v.44 no.3
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• pp.155-173
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• 2010

In this study, a new keyword extraction algorithm is applied to a single document with term clustering. A single document is divided by multiple passages, and two ways of calculating similarities between two terms are investigated; the first-order similarity and the second-order distributional similarity. In this experiment, the best cluster performance is achieved with a 50-term passage from the second-order distributional similarity. From the results of first experiment, the second-order distribution similarity was also applied to various keyword extraction methods using statistic information of terms. In the second experiment, pf(paragraph frequency) and $tf{\times}ipf$(term frequency by inverse paragraph frequency) were found to improve the overall performance of keyword extraction. Therefore, it showed that the algorithm fulfills the necessary conditions which good keywords should have.

• Proceedings of the KSRS Conference
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• v.1
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• pp.409-412
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• 2006

Today's commercial high resolution satellite imagery such as IKONOS and QuickBird, offers the potential to extract useful spatial information for geographical database construction and GIS applications. Recognizing this potential use of high resolution satellite imagery, KARI is performing a project for developing Korea multipurpose satellite 3(KOMPSAT-3). Therefore, it is necessary to develop techniques for various GIS applications of KOMPSAT-3, using similar high resolution satellite imagery. As fundamental studies for this purpose, we focused on the extraction of 3D spatial information and the update of existing GIS data from QuickBird imagery. This paper examines the scheme for rectification of high resolution image, and suggests the convenient semi-automatic algorithm for extraction of 3D building information from a single image. The algorithm is based on triangular vector structure that consists of a building bottom point, its corresponding roof point and a shadow end point. The proposed method could increase the number of measurable building, and enhance the digitizing accuracy and the computation efficiency.

• Journal of the Korean Solar Energy Society
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• v.31 no.6
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• pp.66-71
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• 2011

Various single solvents were tested to find the effective solvent for the extraction of algae oil from wet-form Chlorella minutissima. In the case of single solvents, their extractabilities for algae oil were increased with their polarity because the water in wet algae cell is to form a solvent shell around the lipids. Based on these results, the wet-form algae samples were treated with a polar alcohol solvent and then a nonpolar solvent was added in algae residue. In the algae oil extraction by ethanol/n-hexane, total lipid contents were 40-50% and composition of triglyceride in extracted oil was 46.50%. Considering solvent toxicity of conventional solvent mixture such as chloroform and methanol for algae oil extraction, the ethanol/n-hexane system was identified as the effective one for the oil extraction from wet-form Chlorella minutissima.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.11
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• pp.3008-3020
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• 1994

Condensation heat transfer on a single horizontal tube with electric fields (Electro-Hydro-Dynamics, (EHD)) has been studied experimentally. Results are presented for EHD enhanced condensation of R-113 on a single horizontal tube using several electrode geometries. Especially, its attention was focused on the effects of electrode geometry, electric field strength and the gap of the electrode. In this study, single wire, helical, ring and mesh electrode were used. The range of the imposed voltage was 0~20 kV. As the voltage was increased the surface of liquid became an unstable wave, stream jet, liquid column and then liquid extraction in sequence. Among the various kinds of electrodes, the single wire electrode is suitable for practical application.

• ETRI Journal
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• v.25 no.2
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• pp.101-108
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• 2003

This paper proposes an improved vascular pattern extraction algorithm for person verification applications. The proposed direction-based vascular pattern extraction (DBVPE) algorithm is based on the directional information of vascular patterns. It applies two different filters to the input images: row vascular pattern extraction filter (RVPEF) for effective extraction of the abscissa vascular patterns and column vascular pattern extraction filter (CVPEF) for effective extraction of the ordinate vascular patterns. We use the combined output of both filters to obtain the final hand vascular patterns. Unlike the conventional hand vascular pattern extraction algorithm, the directional extraction approach prevents loss of the vascular pattern connectivity. To validate the DBVPE algorithm, we used a prototype system with a DSP processor. The prototype system shows approximately a three-times better false acceptance rate (FAR) than the conventional single filter algorithm.

• Journal of Environmental Health Sciences
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• v.19 no.2
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• pp.40-45
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• 1993

A solvent extraction system of copper-thiocyanate complex into various types of alkylamines such as secondary, tertiary and quaternary ammonium salt for the determination of trace copper by atomic absorption spectrometry is presented. The maximum extraction of copper shows at 0.1 M-thiocyanate and single extraction with 10 ml of 1% amine-MIBK from 50 ml of aqueous solution is enough to be quantitative for micro amounts of copper. The effect of amine diluents and of diverse ions are also examined.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.171-178
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• 2013

BACKGROUND: Consensus of heavy metal phytoavailability in soils needs to be introduced for soil management protocols in relation to safer food production in the contaminated agricultural soils. For this, setting up the method for evaluation of metal phytoavailability in soil is an essential prerequisite. METHODS AND RESULTS: The current study was carried to select a proper single extraction method for determination of phytoavailable metal concentration in soil. Two extraction methods were examined including 1 M $NH_4NO_3$ extraction and 0.01 M $Ca(NO_3)_2$ extraction methods using 142 soil samples collected from the agricultural soils nearby abandoned mining area in Korea. Corelation analysis was conducted between phytoavailable metal concentrations and soil properties potentially influencing on the metal phytoavailability. Both methods showed similar significance (p<0.001) in correlation with soil properties such as soil pH. However, higher correlation coefficients between phytoavailable metal concentrations and soil properties were observed when used $Ca(NO_3)_2$ extraction rather than using $NH_4NO_3$ extraction. CONCLUSION(S): It appeared that 0.01 M $Ca(NO_3)_2$ extraction was better option for determination of phytoavailable metals in soils and further study to test the efficiency of this method is required in combination with plant uptake.

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.321-326
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• 2008

In order to improve the market competitiveness of the processed products of Undaria pinnatifida, various extraction conditions of Undaria pinnatifida were examined to determine the optimal conditions for the extraction of its valuable components. The highest level of alginic acid content was detected after 90 min of typical extraction or after 20 min of pressure extraction, after which the levels decreased slightly. The concentrations of reducing sugar and crude protein were also high after 90 min of typical extraction. Both alginic acid and reducing sugar were extracted in greater amounts using pressure extraction. The reducing sugar content was $2.8{\sim}3.2$ times higher using pressure extraction rather than typical extraction. Furthermore, the extraction results were superior with the, pressure extraction method. The appropriate temperature and duration of extraction were found to be $120^{\circ}C$ for 20 min. The use of a single enzyme yielded better results during extraction compared to the use of a mixture of enzymes. 20 min of pressure extraction followed by the addition of 0.1% pectinase and 2 hr of further extraction at $50^{\circ}C$ yielded high contents of alginic acid and reducing sugar from Undaria pinnatifida.

• Journal of the Korean Geotechnical Society
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• v.16 no.4
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• pp.157-170
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• 2000

In this study, we conducted a combined adsorption-sequential extraction analysis(CASA) to investigate temperature effects of single and competitive adsorption of zinc and copper on natural clays. As a result, it was found out that in a single adsorption of zinc, the adsorption was mostly in the exchangeable phase, with increase n temperature. In a competitive adsorption of zinc, this trend was so strong that the exchangeable phase adsorption increase up to 80~90%. On the other hand, about 50% of copper was adsorbed in the carbonate occluded phase in single and competitive adsorptions. In the single adsorption the adsorption of carbonate occluded phase increased by 5% with the temperature increase and in the competitive adsorption the increase rate is about twice. The adsorption of zinc and copper on natural clays is an endothermic reaction with the exception of exchangeable phase adsorption.

• Journal of the Korea Society of Computer and Information
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• v.22 no.3
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• pp.107-113
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• 2017

Most of online bookstores are providing a user with the bibliographic book information rather than the concrete information such as thematic words and atmosphere. Especially, thematic words help a user to understand books and cast a wide net. In this paper, we propose an efficient extraction method of thematic words from book text by applying the compound noun and noun phrase synthetic method. The compound nouns represent the characteristics of a book in more detail than single nouns. The proposed method extracts the thematic word from book text by recognizing two types of noun phrases, such as a single noun and a compound noun combined with single nouns. The recognized single nouns, compound nouns, and noun phrases are calculated through TF-IDF weights and extracted as main words. In addition, this paper suggests a method to calculate the frequency of subject, object, and other roles separately, not just the sum of the frequencies of all nouns in the TF-IDF calculation method. Experiments is carried out in the field of economic management, and thematic word extraction verification is conducted through survey and book search. Thus, 9 out of the 10 experimental results used in this study indicate that the thematic word extracted by the proposed method is more effective in understanding the content. Also, it is confirmed that the thematic word extracted by the proposed method has a better book search result.