• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.165-167
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• 2008

The performances of tetracycline based cation selective polymeric membrane electrodes of many sets with different plasticizers were investigated as the selectivity of ion-selective electrodes and optodes are greatly influenced by membrane solvent and also controlled by plasticizers. The membrane 1 with Bis(2-ethylhexyl) sebacate (DOS) and additive shows good potentiometric performance toward Ca2+ (slope: 27.8 mV per decade; DL: -4.52) including selectivity. Contrastingly, membrane 4 with Dibutyl phthalate (DBP) shows near-Nernstian response, it has also shown the best measuring range and detection limit for Ca2+ (29.5 mV and -5.10) and Mg2+ (24.4 mV and -5.04) and the least selectivity has been also observed between Ca2+ and Mg2+. When the membrane 1 and 4 were used together to flow system, we could determine the concentration of Ca2+ and Mg2+, simultaneously.

• Journal of Sensor Science and Technology
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• v.20 no.6
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• pp.428-433
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• 2011

We report on the building of a micro sensor array based on typical semiconductor fabrication processes aimed at monitoring selectively a specific gas in ambient of other gases. Chemical sensors can be applied for an electronic nose and/or robots using this technique. Microsensor array was fabricated on the same chip using 0.6${\mu}m$ CMOS technology, and unique gas sensing patterns were obtained by principal component analysis from the array. $SnO_2$/Pt sensor for CO gas showed a high selectivity to buthane gas and humidity. $SnO_2$ sensor for hydrogen gas, however, showed a low selectivity to CO and buthane gas. We can obtain more distinguishable patterns that provide the small sensing deviation(the high seletivity) toward a given analyte in the response space than in the chemical space through the specific parameterization of raw data for chemical image formation.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.49 no.3
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• pp.200-207
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• 2013

This paper presents the mesh selectivity of a net pot for common octopus Octopus minor for the sustainable resources management of common octopus. The filed experiments were carried out the total 10 times in the southern part of coastal sea in Korea from March to May in 2010 using net pots of five different mesh sizes (16, 18, 20, 22 and 26mm). The test of size selectivity, indicated a 50% selection value on the logistic master curve of 3.195, whereby 50% of individuals with a mantle size of approximately 70.3mm selected a mesh size of 22mm. Considering that 50% of common octopus entering sexual maturity have a mantle size of 70.6mm, the optimum mesh size should be equal to, or larger than 22mm.

• Korean Membrane Journal
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• v.2 no.1
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• pp.48-55
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• 2000

In order to improve organic vapor separation efficiency of polydimethylsiloxane (PDMS) membrane, various zeolites (zeolite 4A, zeolite 13X and natural zeolite) were introduced into a thin PDMS film. The measurements of permeability and selectivity of zeolite-filled PDMS membranes were carried out with a CO$_2$gas and a CO$_2$gas/acetic acid vapor mixture, respectively. The CO$_2$permeability of zeolite-filled membranes decreased with increasing zeolite content and then recovered up to 30 wt% content. The effect of zeolite type on the improvement of CO$_2$permeability was found to be in the order of zeolite 13X > natural zeolite > 4A. The CO$_2$selectivity of zeolite-filled membranes was enhanced up to 9 times compared with the selectivity of a pure (unfilled) PDMS membrane. The effect of zeolite type on the improvement of CO$_2$selectivity was found to be in the order of natural zeolite > zeolite 13X > zeolite 4A.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.09a
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• pp.91-95
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• 1998

Selectivity of SiC deposition on a Si substrate partially covered with a masking material was investigated by introducing HCl gas into hexamethyldisilane/H2 gas system during the deposition. the schedule of the precursor and HCl gas flows was modified so that the selectivity of SiC deposition between a Si substrate and a mask material should be improved. It was confirmed that the selectivity of SiC deposition was improved by introducing HCl gas. Also, the pulse gas flow technique was effective to enhance the selectivity.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.385-390
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• 1998

Adozelesin and carzelesin are synthetic analogues of the extremely potent antitumor antibiotic CC-1065, which alkylates N3 of adenine in a consensus sequence $5^1$-(A/T)(A/T)$A^*$ ($A^*$ is the site of alkylation). We have investigated the DNA sequence selectivity of adozelesin and carzelesin by thermally ind ced DNA strand cleavage assay using radiolabeled restriction DNA fragments. An analysis of alkylation patterns shows that the consensus sequences for carzelesin and adozelesin have been found to be $5^1$-(A/T)(A/T)$A^*$ and $5^1$-(A/F)(G/C)(A/T)$A^*$. A new consensus sequence, $5^1$-(A/T)(A/T)$CA^*$, has been observed to display an additional alkylation site for adozelesin but not for carzelesin. These results indicate that the pattern of sequence selectivity induced by carzelesin is similar but not identical to those induced by adozelosin.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.766-768
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• 2003

Selectivity estimation for spatial query is curial in Spatial Database Management Systems(SDBMS). Many works have been performed to estimate accurate selectivity. Although they deal with some problems such as false-count, multi-count arising from properties of spatial dataset, they can not get such effects in little memory space.* Therefore, we need to compress spatial dataset into little memory. In this paper, we propose a new technique called MW Histogram which is able to compress summary data and get reasonable results. Our method is based on two techniques:(a)MinSkew partitioning algorithm which deal with skewed spatial datasets. efficiently (b) Wavelet transformation which compression effect is proven. We evaluate our method via real datasets. The experimental result shows that the MW Histogram has the ability of providing estimates with low relative error and retaining the similar estimates even if memory space is small.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2187-2190
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• 2013

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.280-282
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• 2014

• Bulletin of the Korean Chemical Society
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• v.27 no.2
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• pp.315-318
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• 2006