• Corrosion Science and Technology
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• v.13 no.4
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• pp.152-156
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• 2014

This study was undertaken to examine the electrochemical corrosion properties of an $Co_{80}Nb_{10}B_{10}$ and $Co_{82}Nb_8B_{10}$ amorphous alloys prepared by melt-spinning method under various conditions. The potentiodynamic polarization responses at various levels of pH (pH 2, pH 7, pH 12) showed that the corrosion current rate of $Co_{80}Nb_{10}B_{10}$ alloy is lower than that of $Co_{82}Nb_8B_{10}$ alloy in all levels of pH, implying the general corrosion resistance of the alloy with higher Nb content is better than that with higher Co content. The pitting potential of $Co_{80}Nb_{10}B_{10}$ alloy was also better than that of $Co_{82}Nb_8B_{10}$, evidenced by the higher pitting potential. Nb is thought to be effective in increasing the protectiveness of the passive film and hence to improve the corrosion resistance of Co-Nb-B alloys.

• Journal of Information Technology Services
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• v.13 no.4
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• pp.139-153
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• 2014

The purpose of this study is to examine the impact of relationship quality on customer value, customer satisfaction and relationship retention intention in the B2B transaction relationship. For the empirical study, we conducted a survey of the PCB corporation's client companies and used 110 surveys of them for analysis. The results of this study are summarized as follows : First, trust, relationship satisfaction, unity and performance as factors of relationship quality had significantly positive effect on relationship retention intention by the medium of customer satisfaction. Second, utilitarian value which is a parameter did not have significantly effect on customer satisfaction and relationship retention intention. Whereas, hedonic value which is influenced by relationship satisfaction, unity and performance had significantly positive effect on customer satisfaction and relationship retention intention. These results are not treated weightily in the preceding studies and managing the hedonic value in B2B transaction relationship is considered important to improve the customer satisfaction and relationship retention intention.

• The Journal of Information Systems
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• v.13 no.2
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• pp.173-193
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• 2004

B2C EC has two kinds of perspectives such as technology-oriented and trust-oriented perspectives. As lots of fraud damages on the B2C EC have been reported every day, the trust-oriented perspective receives lots of attention. In this study, an integrative typology for developing and validating trust measures for B2C EC proposed by McKnight et al.(2002a) and McKnight and Chevany(2002b) has been used for trust-oriented perspective, and the TAM(technology acceptance model) model proposed by Fred Davis in 1985 has been used for technology-oriented perspective. An research model had been developed by using the 4 factors of an integrative typology and 5 factors of the TAM model such as perceived usefulness, perceived ease of use, trust beliefs, intention, and actual transaction. All 13 hypotheses had been proposed from this research model and tested by field study. 12 hypotheses, including the 4 f actors of an integrative typology as antecedents on trust beliefs, were significant, whereas the hypothesis 5 on the relationship between structural assurance and perceived ease of use was insignificant. Structures on B2C EC like guarantees, regulations, promises, legal recourse, or other procedures seemed to be difficult to B2C EC customers. Therefore, these structures should be developed more easier to B2C EC customers.

• Korean Journal of Optics and Photonics
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• v.13 no.5
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• pp.414-420
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• 2002

We realized optical logic gates using a bacteriorhodopsin (bR) doped polymer film. The bR undergoes a complex photocycle characterized by several spectroscopically distinct intermediate states. We realized optical logic gates using a He-Ne laser (632.8 nm) and a He-Cd laser (413 nm) that consider B-state and absorption change of M-state in the photocycle of bR. Also, we realized high speed AND logic gate using He-Ne laser (632.8 nm) and the second harmonics at 532 nm from a pulsed Nd-YAG laser that considering absorption spectrum between B-state and K-state.

• ETRI Journal
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• v.30 no.4
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• pp.526-534
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• 2008

This paper presents a fully integrated 0.13 ${\mu}m$ CMOS MB-OFDM UWB transmitter chain (mode 1). The proposed transmitter consists of a low-pass filter, a variable gain amplifier, a voltage-to-current converter, an I/Q up-mixer, a differential-to-single-ended converter, a driver amplifier, and a transmit/receive (T/R) switch. The proposed T/R switch shows an insertion loss of less than 1.5 dB and a Tx/Rx port isolation of more than 27 dB over a 3 GHz to 5 GHz frequency range. All RF/analog circuits have been designed to achieve high linearity and wide bandwidth. The proposed transmitter is implemented using IBM 0.13 ${\mu}m$ CMOS technology. The fabricated transmitter shows a -3 dB bandwidth of 550 MHz at each sub-band center frequency with gain flatness less than 1.5 dB. It also shows a power gain of 0.5 dB, a maximum output power level of 0 dBm, and output IP3 of +9.3 dBm. It consumes a total of 54 mA from a 1.5 V supply.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.608-612
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• 2002

The twelve-protostane analogues were synthesized from alisol B 23-acetate and assessed for their in vitro antitumor activity against six different human and murine tumor cell lines. Of the compounds synthesized, 23S-acetoxy-24R(25)-epoxy-11$\beta$,23S-dihydroxyprotost-13(17)-en-3-hy-droxyimine (12) exhibited significant cytotoxic activities against A549, SK-OV3, B16-F10, and HT1080 tumor cells with $ED_{50}/$ values of 10.0, 8.7 ,5.2, and 3.1 ${\mu}g$/ml, respectively. Furthermore, 23S-acetoxy-13(17),24R(25)-diepoxy-11$\beta$-hydroxyprotost-3-one (5), 13(17),24R(25)-diepoxy-11$\beta$, 23S-dihydroxyprotostan-3-one (6), 24R,25-epoxy-11$\beta$,23S-dihydroxyprotost-13(17)-en-3-one (7), and 11$\beta$,23S,24R,25-tetrahydroxyprotost-13(17)-en-3-one (9) showed moderate cytotoxic activities against 816-F10 and HT1080 tumor cells. These results mean that a hydroxyimino group at C-3 position in the protostane-type terpene enhances cytotoxic activity.

• Journal of the Korean Society for Nondestructive Testing
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• v.14 no.3
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• pp.151-156
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• 1994

Exertion has been made to develop high-temperature (about $250{\sim}650^{\circ}C$) immersion ultrasonic sensor for the visualization of objects, temperature measurement, dimensional check, or nondestructive testing of welds under liquid sodium. In this study, the feasibility of the ultrasonic sensor taking advantage of a strip waveguide was confirmed by water-experiment. The lowest order of antisymmetric Lamb wave was used in the frequency range with negligible dispersion. This plate wave was excited in the stainless steel strip waveguide of 1.0mm thickness and 13mm width by the comb-structure transducer of 2.3MHz frequency. Its attenuation coefficient was 1.2dB/m in air and 380dB/m in water. The signal to noise ratio of 25dB was obtained from a planar reflector 270mm away from the beam aperture of $13mm{\times}39mm$ size.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.374-383
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• 2013

This paper presents a design for improvement of isolation characteristics by the inserted stub structure on ground plane of a handy terminal which is composed of a main antenna and a sub antenna covered LTE bandwidth. In order to compensate for a resonance length of proposed antenna and to realize a high isolation characteristic, a pair of stub was inserted and located on ground plane that currents from two antennas were converged. A simulated isolation characteristic of antenna without stub at the LTE class 13 band was about -5 dB, but its characteristics of proposed antenna with two stubs at uplink(777~787 MHz) and downlink(746~756 MHz) of the LTE class 13 band were about -12 dB and -15 dB, respectively. An average gain of a fabricated antenna with two stubs was observed about -2 dBi above and it showed good results with comparison of business condition that the average gain of commercial handy terminal has to appear -4 dBi above. The measured S-parameter characteristics and radiation patterns showed a reasonable agreement with the simulation results.

• Research in Plant Disease
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• v.15 no.2
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• pp.130-133
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• 2009

We have conducted in vitro experiments with nano-silver liquid for their effect against various plant pathogenic bacteria. Different types of nano-silver liquid WA-CV-WA13B, WA-AT-WB13R and WA-PR-WB13R were used. These are classified based on different manufacturing processes. The tested bacteria were provided by KACC. We experimented ten bacterial isolates in Clavibacter, Erwinia, Pseudomonas, Ralstonia, and Xanthomonas genera. In order to determine the level of concentrations of control effects, different concentrations (10, 25, 50, and 100 ppm) of each different nano-silver liquid were added in the culture media. As a result, WA-CV-WA13B showed high inhibition effect against C-1 at 10 ppm, and showed minor inhibition effects against P-6, X-1, and X-2. WA-AT-WB13R showed bactericidal effect against P-6 at 10 ppm. At 10 ppm, WA-AT-WB13R showed relatively high inhibition effects against C-1, X-1, and X-2. WA-PR-WB13R showed bactericidal effects against P-5, P-6 and X-2 at 10 ppm or higher concentrations. All the tested three nano-silver liquid showed bactericidal effects against all the tested plant pathogenic bacteria at concentrations of 25 ppm or higher. These results indicated the possible use of nano-silver liquid for the control of plant pathogenic bacteria.

• Current Research on Agriculture and Life Sciences
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• v.1
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• pp.165-167
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• 1983

Oxy - and metmyoglobin concentrations in beef chuck were measured by Hunter-Lab and spectrophotometer. The values of oxymyoglobin by Hunter-Lab got 34.03, 10.40, and 6.50 as average in L, a, and b while the CIE color primaries were 13.33, 11.58, and 9.94 in X, Y, and Z, respectively. The metmyoglobin values recorded 39.10, 13.20, and 10.13 in L, a, and b, of which values were converted to 17.88, 15.29, and 11.40 in X, Y, and Z of the CIE primaries. Absorption spectrum of oxymyoglobin showed 2 peaks which were 0.79 and 0.83 pf extinction coefficient with 530 and 570nm in wavelengh, and that of metmyoglobin appeared on an irregular curve with a summit of 0.58 and 500 in extinction coeffcient ($cm^2$/mg) and wavelength(nm) each.