• Membrane Journal
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• v.13 no.4
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• pp.211-218
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• 2003

The removal characteristics of cadmium in micellar enhanced ultrafiltration (MEUF) were investigated by using an anionic biosurfactant, deoxycholic acid (DCA). The ultrafiltration experiments were performed in a batch-type stirred cell. The ultrafiltration membranes used were Millipore YM1, YM3, YM10, and YM30 which had a difference in molecular weight cut-off. The presence of cadmium ion in DCA solution tends to reduce the critical micell concentration considerably and increase the micell size. The molecular weight cut-off of ultrafiltration membrane had a minimal effect on cadmium removal whereas DCA/Cd ratio had a substantial influence. When DCA/Cd ratio was 3, the removal efficiency of cadmium was more than 99.6%. A relative flux, which is defined as ratio of the flux for a separation trial to that of deionized water run using the same piece of membrane, decreased in the order of YM3 > YM1 > YM10 > YM30.

• Restorative Dentistry and Endodontics
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• v.14 no.2
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• pp.65-76
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• 1989

The purpose of this study was to observe the effect on the removal of dentinal smear layer and morphological changes of reduced dentin surfaces by various dentin surface conditioners. Thirty-two healthy human premolars extracted due to periodontal or orthodontic reasons were used. The teeth were cross-sectioned to expose dentin at the middle portion of the crown with diamond rotary saw. The specimens were then divided into 8 groups. The sectioned dentin surfaces in group 1 to 4 were grinded with No. 400 grit silicone abrasive paper and those in group 5 to 8 were cut with #700 carbide bur under air-water spray. The grinded or cut dentin surfaces were conditioned with 3% $H_2O$, Dentin Conditioner(GC Inter. Corp., Japan), and Scotchprep(3M Dent Prod., U.S.A) according to manufacturer's directions. All the specimens were dried in room temperature for 48 hours, and gold-coated with Eiko ion coater(Eik-engineering Co.), and observed in Hitachi S-450 Scanning electron microscope at 15-25 KV. The following results were obtained; 1. The dentin surfaces grinded with the silicon abrasive paper were rougher in texture and heavier in amount of smear layer than those cut with the carbide bur. 2. Scrubbing of 3% $H_2O_2$ was not effective in removing dentinal smear layer. 3. 20-second conditioning of Dentin Conditioner (GC Inter. Corp) resulted in the removal of a significant amount of the smear layer without removing the tubular plugs and dissolving the peritubular dentin. 4. Scotchprep removed the smear layer very effectively. But at the same time it dissolved the peritubular dentin. 5. Irrespective of the uses of the silicon carbide abrasive paper or the carbide bur the morphological changes of dentin surfaces treated with the same conditioning agents were similar.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.215-217
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• 2008

The most widely used method for searching contents of mot ion picture compares contents by extracted cuts. The cut extract ion methods, such as CHD(Color Histogram Difference) or ECR(Edge Change Ratio), are very weak at modifications such as cropping, resizing and low bit rate. The suggested method uses audio contents for indexing and searching to make search be robust against these modification. Scenes of audio contents are extracted for modification-robust search. And based on these scenes, make spectral powers binary on each frequency bin. in the time-frequency domain. The suggested method shows failure rate less than 1% on the false positive error and the true negative error to the modified(using cropping, clipping, row bit rate, addtive frame) contents.

• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.2
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• pp.113-119
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• 2005

4H-SiC planar MESFETs were fabricated using ion-implantation on semi-insulating substrate without recess gate etching. A modified RCA method was used to clean the substrate before each procedure. A thin, thermal oxide layer was grown to passivate the surface and then a thick field oxide was deposited by CVD. The fabricated MESFET showed good contact properties and DC/RF performances. The maximum oscillation frequency of 34 GHz and the cut-off frequency of 9.3 GHz were obtained. The power gain was 10.1 dB and the output power of 1.4 W was obtained for 1 mm-gate length device at 2 GHz. The fabricated MESFETs showed the charge trapping-free characteristics and were characterized by the extracted small-signal equivalent circuit parameters.

• Korean journal of food and cookery science
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• v.24 no.3
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• pp.349-357
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• 2008

In an effort to augment extractability of carnosine and anserine at the levels of pro-oxidants such as iron and protein in Tuna boiled extracts(Skipjack, Yellowfin and Bigeye), we assessed the effects of heated and ion exchange chromatography(IEC) and ultrafiltration(UF) using a MW 500 cut-off(500 MWCO). We also evaluated the antioxidant activity of these extracts processed as free radical scavengers and reducing agents. Tuna boiled extracts of dark and ordinary muscle protein and total iron were reduced, whereas carnosine and anserine concentrations and antioxidant activity were increased. The carnosine and anserine concentrations of the ion exchange and permeate UF(IEC-UF) extracts were higher than those observed in the heated and permeate UF(heat-UF), whereas the protein and total iron contents were lower than that observed in the heat-UF. The quantity of carnosine and anserine in ordinary muscle was higher than that detected in dark muscle. HPLC analysis and SDS-PAGE were shown to removes the effect of UF on high molecular weight impurities in the tuna boiled extracts. The major free amino acids(FFAs) from Skipjack, Yellowfin and Bigeye tuna IEC-UF extracts were anserine, histidine and carnosine. These three peptides constituted more than 80～85%. of the detected amino acid. The IEC-UF treated ordinary muscle extracts evidenced the highest levels of DPPH radical scavenging activity and the highest levels of reducing power among the various extracts. The IEC-UF extracts evidenced a DPPH radical scavenging effect equal to that of 1mM ascorbic acid.

• Korean Chemical Engineering Research
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• v.49 no.6
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• pp.745-751
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• 2011

In this study, zinc or cerium exchanged zeolite was introduced to develop a novel anti-corrosion pigment. The primer paint was made using them and was coated on galvanized(GI) steel. The anti-corrosion performance was measured using electrochemical impedance spectroscopy(EIS). And scanning vibrating electrode technique(SVET) was employed to observe the cut-edge corrosion process of the coated GI steel. From EIS and SVET results, it could be confirmed that Ce ion-exchanged zeolite showed the anti-corrosion performance higher than Shieldex C303 and Zn ionexchanged zeolite. Finally, it was found that metal ion-exchanged zeolite may provide new possibility as the smart cathodic corrosion inhibitor delivery systems on galvanized steels.

• Journal of Photoscience
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• v.9 no.2
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• pp.448-450
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• 2002

DNA samples extracted from Japanese cypress leaf tissues contain isopropyl alcohol-precipitable, high molecular weight compounds, which interfere ELISA for cyclobutane pyrimidine dimers (CPD). Removal of the compounds is achieved by DEAE ion-exchange column chromatography and improves the ELISA responses of the DNA. When extracting DNA repeatedly from the same leaf tissues, the DNA samples show CPD responses which increase with the order in sequential extraction, and hence for a reliable detennination of DNA lesion a thorough extraction of DNA is required. Clearing these two problems it was demonstrated that CPD level was slightly higher in the leaves of trees growing under full sunlight than in those growing under UBV -cut sunlight.

• Journal of the Korean Vacuum Society
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• v.8 no.4B
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• pp.536-540
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• 1999

We have developed a refractory WNx self-aligned gate GaAs metal-semiconductor field-effect transistor(MESFET) using $SiO_2$ side-wall process. The MESFET hasa fully ion-implanted, planar, symmetric self-alignment structure, and it is quite suitable for integration. The uniform trans-conductance of 354nS/mm up to Vgs=+0.6V and the saturation current of 171mA/mm were obtained. As high as 43GHz of cut-off frequency hs been realized without any de-embedding of parasitic effects. The refractory WNx self-aligned gate GaAs MESFET technology is one of the most promising candidates for realizing linear power amplifier ICs and multifunction monolithic ICs for use in the digital mobile communication systems such as hand-held phone(HHP), personal communication system (PCS) and wireless local loop(WLL).

• Culinary science and hospitality research
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• v.8 no.1
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• pp.149-170
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• 2002

As the life style of modern people is gradually being more scientific, up-to-date, and specialized, food habit and food cut lure are a measure of cultural level of a country. Studies on consumer behavioral model show that food habit is closely related to consumer preference, changing life pattern and increasing family income. The purpose of this study was, accordingly, to define the impact of menu characteristics on customer menu selection. For that purpose, some at tempts were made: First, discuss the theories on family restaurant and customer purchasing behavior as a standard of analysis. Second, find out if there are any differences in customer menu- selection factors in family restaurant Third, make an empirical analysis of menu-selection factors in family restaurant to suggest in which direction it should move forward Fourth, analyze the relationship of demographic characteristics to menu-select ion factors.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.412-415
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• 1999

In this paper, we describe an implementation of the B-Link bus interface logic for a directory controller and a remote access cash controller in the SCI-based CC-NUMA multimedia server developed by ETRI . The CC-NUMA multimedia server is composed of a number of Pentium III SHV nodes and a SCI interconnection network. To communicate with remote nodes, each node has a CC-Agent which consists of a processor bus interface(PIF). a directory controller(DC), a remote access cash controller(RC), and two SCI 1ink controllers(LCs). The B-Link bus interface logic is developed for a directory controller and a remote access cash controller in order to communicate with a SCI link controller on a B-Link bus. It consists of a sending master controller a receiving slave controller, and asynchronous data buffers. And It performs a self-arbitration, a data packet transmission, a queue allocation, an early terminal ion. and a cut-through data path.