• Journal of the Korean Society for Library and Information Science
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• v.47 no.1
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• pp.269-286
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• 2013

The advent of Web 2.0 and social media is taking a leading role of emerging big data. At the same time, however, informational dysfunction such as infringement of one's rights and violation of social order has been increasing sharply. This study, therefore, aims at defining malicious usage, identifying malicious feature, and devising an automated method for classifying them. In particular, the rule-based experiment reveals statistically significant performance enhancement.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.6
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• pp.1431-1438
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• 1995

In this paper, we present a multiple-view stereo matching method in case of moving in the direction of optical axis with stereo camera. Also we analyze the obtainable depth precision to show that multiple-view stereo increases the virtual baseline with single-view stereo. This method decides candidate points for correspondence in each image pair and then search for the correct combinations of correspondences among them using the geometrical consistency they must satisfy. Adantages of this method are capability in increasing the accuracy in matching by using the multiple stereo images and less computation due to local processing. This method computes 3-D depth by averaging the depth obtained in each multiple-view stereo. We show that the resulting depth has more precision than depth obtainable by each independent stereo when the position of image feature is uncertain due to image noise. This paper first defines a multipleview stereo agorithm in case of moving in the direction of optical axis with stereo camera and analyze the obtainable precision of computed depth. Then we represent the effect of removing the incorrect matching candidate and precision enhancement with experimental result.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.44.2-44.2
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• 2013

The local environmental effects on the active galactic nucleus(AGN) activity has been studied by many authors, but there is still controversy. We performed statistical analysis for nearby(0.01 < z < 0.05) volume limited(Mr < -19) sample via visual inspection based on Sloan Digital Sky Survey Data Release7. We visually inspect around 50,000 galaxy images to find peculiar objects which show not only ongoing merging features and tidal features, but also post merging features like shell or ring structures. We found that the frequency of AGN host galaxies is at least 2 times higher among peculiar galaxies than non-peculiar galaxies, and this trend is still visible when galaxy properties such as color or stellar mass are fixed. Furthermore, L[OIII] of peculiar galaxies is found to be more increased than those of normal galaxies. The majority of the most luminous AGN hosts show peculiar feature, which indicates that the luminous AGN galaxies may be the result of the local environmental effects. In addition, the enhancement of L[OIII] in peculiar galaxies is more significant for bluer galaxies, which implies that AGN activity is enhanced effectively when gas is available. In order to ensure our results, we also checked it for a smaller subsample with 2 magnitude deeper monochromatic images provided by SDSS Stripe82 database, and found consistent results. Overall, the results of this study tell us that the local environment of galaxies affects the frequency as well as the strength of AGN activity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.6
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• pp.864-871
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• 2015

Recently, one of the main research on the power distribution system is the microgrid. The microgrid is a combination of power sources and loads, which is controllable and has separable connection. The main objective of microgrid is the deployment of the renewable clean energy and the enhancement of load-side reliability. The modern power sources and loads have DC I/O interfaces, which is the major advantage of DC microgrid compared to the conventional AC grid. The components in the microgrid have diverse features, so there is need of proper coordination control. For achieving economic feature, the active power of renewable energy resources is regarded as major control parameter and the whole operation modes of DC microgrid are defined, and the proper operations of each component are described. From the inherent characteristics of DC, there are two control variables: voltage and active power. Through analysis of operation modes, it is possible to determine exact control objectives and optimized voltage & power control strategy in each mode. Because of consideration of whole operation modes, regardless of the number and capacity of components, this coordination control method can be used without modification. This paper defines operation mode of DC microgrid with several DC sources and suggests economic and efficient coordinated control methods. Simulation with PSCAD proves effectiveness.

• Journal of the Korea Computer Industry Society
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• v.4 no.4
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• pp.647-660
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• 2003

The present of state is situation that is realized by necessity of maintenance of public security about great many information is real condition been increasing continually in knowledge info-age been situating in wide field of national defense, public peace, banking, politics, education etc. Also, loss or forgetfulness, and peculation by ID for individual information and number increase of password in Internet called that is sea of information is resulting various social problem. By alternative about these problem, including Biometrics, several authentication systems through sign(Signature), Smart Card, Watermarking technology are developed. Therefore, This paper shows that extract factor that efficiency can get into peculiar feature in physical features for good fingerprint recognition algorithm implementation with old study finding that take advantage of special quality of these fingerprint.

• Journal of Pharmaceutical Investigation
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• v.25 no.3
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• pp.43-51
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• 1995

The in vitro skin permeability of 16 drugs with a wide span of lipophilicity (log P ranging from -0,95 to 4.40) was evaluated with an ethanol/panasate 800 (tricaprylin, P-800) (40/60) lipophilic binary vehicle and an ethanol/water (60/40) hydrophilic binary vehicle with lauric acid, The skin permeability of the drugs was enhanced by the use of the ethanol/P-800 (40/60) binary vehicle or the ethanol/water (60/40) binary vehicle with lauric acid; permeation rate was increased and lag time' was decreased. The relationship between lipophilicity and skin permeation rate of the drugs showed parabolic shapes with their peaks at much greater hydrophilic range compared with other past references. In the in vivo skin absorption of theophylline using abdominal rat skin, the ethanol/P-800 (40/60)-7% (w/w) ethycellulose gel produced a good feature as a sustained-release preparation, and the ethanol/water (60/40)-3 % (w/w) HPMC gel with lauric acid showed the highest BA value. The results suggest that the lipophilicity of a drug is a main factor for prediction of the skin permeability of the drug and that the ethanol/P-800 (40/60) binary vehicle and ethanol/water (60/40) binary vehicle with lauric acid would be good candidates for clinical transdermal application of hydrophilic drugs.

• Journal of Korean Neurosurgical Society
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• v.52 no.1
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• pp.52-54
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• 2012

A 10-year-old female patient presented with a rapidly growing nodular mass lesion on her right frontal area. On skull radiography and computed tomography (CT) imaging, this mass had a well-demarcated punch-out lesion with a transdiploic, exophytic soft tissue mass nodule on the frontal scalp. Magnetic resonance (MR) imaging revealed the presence of a $1.5{\times}1.2{\times}1$ cm sized calvarial lesion. This lesion was hypointense on T1 and heterogenous hyperintense on T2 weighted MR images, and exhibited heterogeneous enhancement of the soft tissue filling the punch-out lesion after intravenous administration of gadolinium. En block removal of the tumor with resection of the rim of the normal bone was performed. The pathological diagnosis was intravascular papillary endothelial hyperplasia (IPEH). After surgery, no recurrence was found for 8 months. IPEH is a rare and benign reactive lesion usually found in thrombosed subcutaneous blood vessels. Involvement of skull bone is rare. In this article, we present a case of IPEH involving the calvarium, in a 10-year-old woman.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3377-3381
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• 2011

In this work, the amine grafting treated activated carbons were studied for carbon dioxide adsorbent. The surfaces of activated carbon were functionalized by 3-chloropropyltrimethoxysilane, which was subsequently grafted with amine compounds tris-(2-aminoethyl)amine and tri-ethylenetetramine and subjected to comparison. The surface functional groups of the amine grafted activated carbons were characterized using XPS. The textural properties of the amine grafted activated carbons were analyzed by $N_2$/77 K isotherms. Carbon dioxide adsorption behaviors of the amine grafted activated carbons were examined via the amounts of carbon dioxide adsorption at 298 K and 1.0 atm. From the results, tris-(2-aminoethyl)amine grafted activated carbons showed 43.8 $cm^3$/g of carbon dioxide adsorption while non-treated activated carbons and triethylenetetramine grafted activated carbons showed less carbon dioxide adsorption. These results were thought to be due to the presence of isolated amine groups in the amine compounds. Tris-(2-aminoethyl)amine grafted activated carbons have basic features that result in the enhancement of adsorption capacity of the carbon dioxide molecules, which have an acidic feature.

• Journal of the Korean Data and Information Science Society
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• v.20 no.5
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• pp.869-878
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• 2009

Image restoration techniques such as noise reduction and contrast enhancement have been researched for enhancing a contaminated image by the noise. An image degraded by additive random noise can be enhanced by noise reduction. Sigma filtering is one of the most widely used method to reduce the noise. In this paper, we propose a new sigma filter algorithm based on noise variance estimation which effectively enhances the degraded image by noise. Specifically, the Bartlett test is used to measure the degree of noise with respect to the degree of image feature. Simulation results are also given to show the performance of the proposed algorithm.

• The Korean Journal of Cytopathology
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• v.6 no.2
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• pp.199-203
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• 1995

Chordoma is relatively uncommon tumor comprising $1\sim4%$ of primary malignant bone tumors, and believed to arise from the remnants of notochordal tissue. Because of its rare occurrence in the thoracic spine, we report a case of chordoma involving the thoracic spine. A 45-year-old male was sufferred from chest pain radiating to the back. Chest CT showed a well marginated, round huge mass with multiseptated enhancement at the thoracic spine from T5 to T8 level. After percutaneous needle aspiration, piecemeal resection of the tumor was done. On cytologic smears, two types of neoplastic cells were arranged in sheets and cords in mucinous background. One type of cells consisted of medium sized cells with pink cytoplasm and round nuclei. The other type had voluminous bubbly or clear cytoplasm divided by intracytoplasmic septae imparting a feathery or basket-like appearance. Histologically, the tumor showed lobulated feature divided by fibrous septae and the tumor cells were pink eosinophilic or physaliphorous in morphology. Immunohistochemically, the tumor cells revealed strong positivity for low(AE1) and high (AE3) molecular weight cytokeratins.