• Journal of Korean Society of Environmental Engineers
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• v.32 no.9
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• pp.840-850
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• 2010

The present study was attempted to find the effects of structural properties of phosphorus on the water quality of Gyehwa reservoir in Saemangeum. Relationship of phosphorus fractions between water and sediment properties was closely examined, and a few types of phosphorus were found from the sample sediment as : Saloid-P, Al-P, Fe-P, Ca-P, Red-P and Occd-P. Saloid-P (1.4%), Al-P (0.5%), Fe-P (39.8%), Ca-P (56.6%), Red-P (0.4%), Occd-P (1.3%) were extracted in a mass basis from the sediment of Gyehwa reservoir. Approximately more than 97% of phosphorus were calcium related phosphorus (Ca-P, 56%) and iron bound phosphorus (Fe-P, 39.8%). The Fe-P closely relates with water quality of T-N (r=0.761, p<0.05), $NO_3$-N (r=0.754, p<0.05), $NH_4$-N (r=0.728, p<0.05), T-P (r=0.774, p<0.05) and $PO_4$-P (r=0.767, p<0.05) while the Ca-P did not show any consistent dependency on the water quality. On the other hand, the correlation of Ca-P with $P_2O_5$ was high with r=0.783 (p<0.05) in the sediment. The Fe-P was affected significantly on the Ignition Loss (r=0.569, p<0.05), T-N (r=0.715, p<0.05) and T-P (r=0.983, p<0.01). In the research of correlation between phosphorus fraction and heavy metals in the sediment, Ca-P did not show any specific relationships with heavy metals. The Fe-P showed a significant correlation with As (r=0.817, p<0.01), Cu (r=0.793, p<0.05), Cd (r=0.786, p<0.05), Zn (r=0.738, p<0.05), so that it can be stated that the presence of Fe-P may implicate the volume of various metallic elements.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.5
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• pp.1089-1097
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• 2016

It is well-known that, if additional information other than a plaintext-ciphertext pair is available, breaking the RSA cryptosystem may be much easier than factorizing the RSA modulus. For example, Coppersmith showed that, given the 1/2 fraction of the least or most significant bits of one of two RSA primes, the RSA modulus can be factorized in a polynomial time. More recently, Henecka et. al showed that the RSA private key of the form (p, q, d, $d_p$, $d_q$) can efficiently be recovered whenever the bits of the private key are erroneous with error rate less than 23.7%. It is notable that their algorithm is based on counting the matching bits between the candidate key bit string and the given decayed RSA private key bit string. And, extending the algorithm, this paper proposes a new RSA private key recovery algorithm using a generalized probabilistic measure for measuring the consistency between the candidate key bits and the given decayed RSA private key bits.

• Membrane and Water Treatment
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• v.15 no.4
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• pp.193-202
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• 2024

It has been reported that rare earth elements (REEs) are considerably present in coal ash. In this study, an ecofriendly sequential extraction method was developed for the effective REE recovery from coal ash and leaching wastewaters. Citrate, a weak and environmentally benign solvent that replaces acetate employed in the existing sequential extraction methods (e.g., European community bureau of reference (BCR) and Tessier methods), was found to be highly effective in leaching REEs from coal ash. Microwave-assisted thermal digestion improved the REE extraction efficiency even further, with an overall leaching rate of 70%, which is 2.54 and 3.76 times higher than the values achieved by the conventional BCR and Tessier methods, respectively. It was also confirmed that the majority of REEs was strongly bound to CaO, Al₂O₃, Fe₂O₃, and P₂O₅, not to SiO₂. The sequential extraction method developed in this study is expected to be used as an effective and simple recovery procedure for REEs from coal ash and remaining leaching wastewaters.

• Membrane Journal
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• v.9 no.2
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• pp.97-106
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• 1999

A and 2SM-5 type zeoli tic crystal films were synthesized on porous supports from the reaction mixture of 1.9 ${SiO}_2$1.5 $Na_20-Al_2O_3-40$ $H_20$ and $Si0_2$-0.l3 $Na_2O$-52 $H_20$-O.l2 TPAOH composition, respectively. The zeolite films were characterized by XRD and SEM. The 2SM -5 crystals grown on the porous matrix were very closely bound together. It was so difficult to obtain the perfectly intergrown crystals in the case of A-type zeolite and this crystal was transformed into P-type zeolite membrane with a prolonged reaction time. The densely intergrown A type zeolite crystal membrane could be also synthesized by the hydrothermal treatment at 100$^{\cirt}C$ after pressing the reaction mixture without addition of water. The pervaporation performance of the synthesized porous inorganic membranes was investigated for alcohol and water mixtures. A-type zeolite membrane crystallized as a thin film showed the selective \'Jermeability of water from the mixtures through the molecular sieving activity of micropores.

• Economic and Environmental Geology
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• v.35 no.4
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• pp.325-337
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• 2002

We examined the contamination of stream water and stream sediments by heavy metal elements with respect to distance from the abandoned Backun Au-Ag-Cu mine. High contents of heavy metals (Pb, Zn, Cu, Cd, Mn, and Fe) and aluminum in the waters connected with mining and associated deposits (dumps, tailings) reduce water quality. In the mining area, Ca and SO$_4$ are predominant cation and anion. The mining water is Ca-SO$_4$ type and is enriched in heavy metals resulted from the weathering of sulfide minerals. This mine drainage water is weakly acid or neutral (pH; 6.5-7.1) because of neutralizing effect by other alkali and alkaline earth elements. The effluent from the mine adit is also weakly acid or neutral, and contains elevated concentrations of most elements due to reactions with ore and gangue minerals in the deposit. The concentration of ions in the Backun mining water is high in the mine adit drainage water and steeply decreased award to down stream. Buffering process can be reasonably considered as a partial natural control of pollution, since the ion concentration becomes lower and the pH value becomes neutralized. In order to evaluate mobility and bioavailability of metals, sequential extraction was used for stream sediments into five operationally defined groups: exchangeable, bound to carbonates, bound to FeMn oxide, bound to organic matter, and residual. The residual fraction was the most abundant pool for Cu(2l-92%), Zn(28-89%) and Pb(23-94%). Almost sediments are low concentrated with Cd(2.7-52.8 mg/kg) than any other elements. But Cd dominate with non stable fraction (68-97%). Upper stream sediments are contaminated with Pb, and down area sediments are enriched with Zn. It is indicate high mobility of Zn and Cd.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.712-720
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• 2008

Sediment and interstitial water samples from ten lagoons in the Northeastern coastal part of South Korea were analyzed to obtain the concentrations of metals and inorganic ligand. These data, coupled with pH and ionic strength, were used to compute the aqueous speciation of the metals in the interstitial water using the MINTEQA2 equilibrium program. The K and Na were almost entirely present as the free aqua ions, but Co, Cd, Ni, Pb and Zn were existed as various metal-ligand complexes. Metals such as Al, As, and Cr formed 3$\sim$4 metal-ligand complexes. In the interstitial water with high chloride concentrations, almost all of the metals were dominated by free aqua ions. Metals of Cd, Co, Ni, Pb and Zn were bound as chloride-metal complexes of the type M$^{x+}$ + xCl$^-$, and Fe, Mn and Mg were dominated by sulfate equilibria(M$^{2+}$ + SO$_4{^{2-}}$). Hg(II) was speciated as HgCl$_2$(aq), HgCl$_3{^-}$ and HgCl$_4{^-}$. However, in the interstitial water with low chloride concentrations, Hg(II) and Cd(II) were existed as chloride-metal complexes, metals of Cu, Mg, Mn, Ni, Pb and Zn were dominated by sulfate equilibria, and the speciation of Fe(II) was bound as Fe(OH)$_2{^+}$, Fe(OH)$_3$(aq). However, Al, As and Cr were dominated by hydroxy-metal and oxide-metal species in nearly all of the lagoons.

• Journal of fish pathology
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• v.20 no.2
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• pp.119-127
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• 2007

Phosphoinositide-specific phospholipase Cδ (PLCδ) plays an important role in many cellular responses and is involved in the production of second messenger. The present study was conducted to characterize the catalytic and regulatory properties of the PLCδ of Misgurnus mizolepis (ML-PLCδ). The ML-PLCδ gene was cloned and expressed under according to the method of the previous report (Kim et al., 2004), and its recombinant protein was purified by successive chromatography using Ni2+-NTA affinity column. The recombinant ML-PLCδ showed a concentration-dependent PLC activity to phosphatidylinositol 4,5-bisphosphate (PIP2) or phosphatidylinositol (PI). Its activity was absolutely Ca2+-dependence, which was similar to mammalian PLCδ isozymes. The Ca2+ concentration yielding maximal activation of ML-PLCδ was 100 μM. However, the activity was decreased interestingly by a polyamine, such as spermine and spermidine. In vitro assay using cholate-micelle cell, ML-PLCδ activity was inhibited in dose-dependent manner by sphinogosine but increased by phosphocholine . In the lipid-binding assay, ML-PLCδ was strongly bound to LPA, PI(3)P, PI(4)P, PI(5)P, PI(3,5)P2, PI(4,5)P2, PI(3,4,5)P3 and PA, but it showed the low affinity to S1P, PI(3,4)P2 and PS. Taken together our results, it is suggested that the general catalytic and regulatory properties of ML-PLCδ are similar with those of mammalian PLCδ1 isozymes, but the N-terminal extended piscine phospholipase Cδ1 (ML-PLCδ) might reflect some distinctions in regulatory properties and inositol-lipid binding specificity between piscine ML-PLCδ and mammalian PLCδ isozymes.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.89-89
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• 2003

Exposure of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes a variety of biological and toxicology effects, most of which are mediated by aryl hydrocarbon receptor (AhR). The ligand-bound AhR as a heterodimer with AhR nuclear translocator (ARNT) binds to its specific DNA recognition site, the dioxin-responsive element (DRE), and it results in increased transcription of CYP1A1 gene. Retinoic acid (RA) regulates the transcription of various genes for several essential functions through binding to two classes of nuclear receptors, the retinoic acid receptor (RAR) and retinoid X receptor (RXR). Constitutive androstane receptor (CAR) also regulates the transcription of gene. In this study, we have examined how RAR, RXR and CAR regulated CYP1A1 in rainbow trout hepatoma cell (RTH 149) using luciferase reporter gene assay system. We did transient transfection with CYP1A1 luciferase reporter gene and treated with TCDD, all-trans RA, 9-cis RA and phenobarbital. Treatment of all-trans RA, 9-cis RA or phenobarbital decreased the TCDD induced transcription of CYP1Al. When we did transient cotransfection with CYP1A1 luciferase reporter gene and RXR, as increase of RXR concentration, the TCDD induced transcription of CYP1A1 was decreased. Transfection with CAR also decreased the TCDD induced transcription of CYP1A1 in RTH 149 cells.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.1-6
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• 1977

Fifteen soils including volcanic ash, acid sulfate and degraded saline soils were investigated for Languir adsorption isotherm of ammonium using $NH_4H_2PO_4$. The results are as follows. Languir adsorption maxima of ammonium (LAMA) ranged from 2.4me/100g soil to 12.3 and the average was 5.3. Initial concentration of 30 to 60 or 40 to 80 ppm(as N) appears to be suitable for LAMA measurement. There were two LAMA in some soils. Difference between adsorption constants (bonding energy) was mostly greater than that between LAMA. LAMA ranged from 9.4% to 72% of cation exchange capacity and average was 47%. It did not show any clear tendency with CEC, pH, organic matter content, base saturation percent, P, K, Ca, Mg, Na and Si. Except volcanic ash soils which were grouped into two groups according to ammonium adsorption LAMA was significantly (r=0.951 at 1%) correlated with adsorption at 200ppm. This single concentration seems suitable for LAMA measurement. Probable mechanism of ammonium adsorption was discussed, in which the associated anions were combined with iron and aluminum and then ammonium was bound to phosphorus. Applicability of Langmuir adsorption isotherm model to the soils under field condition was also discussed.

• The KIPS Transactions:PartD
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• v.9D no.2
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• pp.173-184
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• 2002

This paper discuss an index-based subsequence matching that supports time warping in large sequence databases. Time warping enables finding sequences with similar patterns even when they are of different lengths. In earlier work, Kim et al. suggested an efficient method for whole matching under time warping. This method constructs a multidimensional index on a set of feature vectors, which are invariant to time warping, from data sequences. For filtering at feature space, it also applies a lower-bound function, which consistently underestimates the time warping distance as well as satisfies the triangular inequality. In this paper, we incorporate the prefix-querying approach based on sliding windows into the earlier approach. For indexing, we extract a feature vector from every subsequence inside a sliding window and construct a multidimensional index using a feature vector as indexing attributes. For query processing, we perform a series of index searches using the feature vectors of qualifying query prefixes. Our approach provides effective and scalable subsequence matching even with a large volume of a database. We also prove that our approach does not incur false dismissal. To verify the superiority of our approach, we perform extensive experiments. The results reveal that our approach achieves significant speedup with real-world S&P 500 stock data and with very large synthetic data.