• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1237-1244
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• 2006

In order to ensure a stable supply of grapes for consumers and to extend grape storage, we investigated changes in the quality of grapes (Vitis labruscana) stored after treatment with ethylene absorbent (EA) or activated charcoal (AC). We treated harvested 'Sheridan' and 'Muscat Bailey A' grapes with EA and with 0.1, 0.5, 1.0, and 2.0% (w/w) AC, and stored them at $0{\pm}1^{\circ}C$, $90{\pm}2%$ humidity for 60 days. After the EA or AC treatment, the storability of the 'Sheridan' and 'Muscat Bailey A' grapes was increased, as compared with non treatment, and 'Sheridan' kept better than 'Muscat Bailey A'. The quality of the stored grapes maintained with EA or the amount of AC, which decreased the rate of weight loss, abnormal fruit development, berry abscission, saccharinity, and growth of fungi. The free sugar and anthocyanin contents in the pericarp increased gradually in both 'Sheridan' and 'Muscat Bailey A', and increased more in 'Sheridan'. Conversely, the total acidity of 'Sheridan' and 'Muscat Bailey A' decreased with storage, and decreased less in 'Sheridan'. There were no differences in the free sugar content, anthocyanin content, and total acidity among treatments. The changes in grape quality with storage were delayed in the order of EA, 2% AC, 1% AC, 0.5% AC, and 0.1% AC. Ultimately, we postulate that EA and 2% AC best maintain the qualities of grape, and extend the grape storage period.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.314-317
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• 1996

In this paper, we present a nonlinear adaptive controller for position tracking of induction motors. In constructing the adaptive controller, a backstepping approach is used under the condition of full state information, while a nonlinear observer is adopted for rotor flux estimation. The adaptive controller is shown to drive the state variables of system to the desired ones asymptotically and whose effectiveness is also shown via computer simulation.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.10
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• pp.936-941
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• 2010

This study was conducted to investigate formaldehyde removals by silver nano-particles attached on the surface of granular activated carbon (Ag-AC) and to compare the results to those obtained with ordinary activated carbon (AC). The BET analysis showed that the overall surface area and the fraction of micropores (less than $20{\AA}$ diameter) of the Ag-AC were significantly decreased because the silver particles blocked the small pores on the surface of the Ag-AC. The formaldehyde removal capacity of the Ag-AC determined using the Freundlich isotherm was higher than that of AC. Despite the decreased BET surface area and micropore volume, the Ag-AC had the increased removal capacity for formaldehyde, presumably due to catalytic oxidation by silver nano-particles. In contrast, the adsorption intensity of the Ag-AC, estimated by 1/n in the Freundlich isotherm equation, was similar to that of the ordinary AC, indicating that the surface modification using silver nano-particles did not affect the adsorption characteristics of AC. In a column experiment, the Ag-AC also showed a longer breakthrough time than that of the AC. Simulation results using the homogeneous surface diffusion model (HSDM) were well fitted to the breakthrough curve of formaldehyde for the ordinary AC, but the predictions showed substantial deviations from the experimental data for the Ag-AC. The discrepancy was due to the catalytic oxidation of silver nano-particles that was not incorporated in the HSDM. Consequently, a new numerical model that takes the catalytic oxidation into accounts needs to be developed to predict the combined oxidation and adsorption process more accurately.

• Clinical and Experimental Pediatrics
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• v.50 no.8
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• pp.774-780
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• 2007

Purpose : The anthracyclines (AC) are widely used chemotherapeutic agents for pediatric cancers. However, the therapeutic use of these agents is limited by their cardiotoxicity. The aim of the present study was to investigate the usefulness of plasma B-type natriuretic peptide (BNP) levels as a marker for AC-induced cardiotoxicity compared to echocardiography in Korean children with cancer. Methods : Fifty-five pediatric cancer patients who had received chemotherapy including AC were enrolled. The cumulative AC doses, clinical symptoms, and two echocardiography parameters, left ventricular fractional shortening (LVFS) and left ventricular ejection fraction (LVEF), were studied and compared with plasma BNP levels. Results : In 55 patients, plasma BNP levels were measured 115 times and echocardiographies were performed 64 times. The median cumulative dose of AC was $325mg/m^2$ (range 120-600; mean 345) and the median plasma BNP level was 10 pg/mL (range 5-950; mean 31). The cumulative AC doses correlated significantly with the plasma BNP levels (P=0.002). The plasma BNP levels correlated significantly with LVFS (P=0.018) and LVEF (P=0.025). Dilated cardiomyopathies were identified in three patients. LVFS and LVEF decreased and plasma BNP levels increased in a patient with acute dilated cardiomyopathy and in that with symptomatic chronic dilated cardiomyopathy. However, LVFS, LVEF and plasma BNP levels were normal in a patient with asymptomatic chronic dilated cardiomyopathy. Conclusion : The results of this study demonstrated that plasma BNP levels could be used as a marker for AC-induced cardiotoxicity; they showed good correlation with echocardiography findings in pediatric cancer patients. Plasma BNP levels may be used for the detection and management of AC-induced cardiotoxicity in Korean children with cancer.

• Journal of the Korean Magnetics Society
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• v.26 no.1
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• pp.19-23
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• 2016

In this study, we have constructed a measuring system to investigate tensile stress measurement of tendons, which is employed in bridges, by means of the non-destructive and non-contact method. The measuring system consists of tensile stress applying apparatus up to 2 GPa, and power supply for ac and dc current to tendon directly to magnetize tendon in circular direction and to coil wound on yoke to magnetize tendon in axial direction. We have used two kinds of tendon, which were produced by different companies, using the measuring system constructed in this work. Two kinds of experiments are carried out in this work; $1^{st}$ experiment : ac current was applied to the tendon and dc current was applied to coil wound on the yoke, and voltage induced from search coil wound on yoke (SCY) was measured and $2^{nd}$ experiment : dc current was applied to the tendon and ac current was applied to coil wound on the yoke, and voltage induced from search coil on tendon (SCT) was measured. In case of $1^{st}$ experiment, voltage induced from SCY was changed below 200MPa tensile stress but the voltage was not increased above 200 MPa. In case of $2^{nd}$ experiment, voltage induced from SCT was decreased up to 1.5 GPa linearly. We expect that $2^{nd}$ experiment could be applied to the non-destructive testing of tensile stress measurement of tendon.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.11
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• pp.91-98
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• 2004

TFLIM(Transverse Flux Linear Induction Motor), making its closed magnetic path with the direction of the traveling field orthogonal, had been developed to decrease an edge effect of the general induction motor. To control the levitation force and the thrust force on the secondary part of TFLIM independently, the various methodologies have been presented. When we try to achieve the independent control using only the multi-phase inputs assigned in the stator coils as an approach, in which condition we can minimize the coupling effect between two forces\ulcorner In this paper, we show the qualitative influence of a slip frequency, an ac magnitude, a dc offset superposed in the ac power, and a major parameter of TFLIM on the couple through the computer simulation. And to realize the independent motions between levitation and thrust motion without any auxiliary means fur isolation of the secondary part of TFLIM, the decouple compensator is suggested, including the experimental results.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.221-233
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• 2021

This study empirically examined the relationships among ethical leadership, supervisor identification(SI), affective commitment(AC), and unethical pro-supervisor behavior(UPSB) based on social learning theory and social exchange theory. The data were collected by conducting a survey of 339 workers and analyzed using SPSS25 and SPSS Process Macro (v3.5). The results were as follows. First, ethical leadership directly negatively influences UPSB. Ethical leadership indirectly positively influences UPSB mediated by SI. Second, ethical leadership, completely mediated by AC, indirectly positively influences UPSB. Third, ethical leadership has an indirect positive effect on AC mediated by SI. This study showed how ethical leadership works in organizations through social learning theory and social exchange theory. Also, it suggested implications on how to use ethical leadership in field.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.462-469
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• 1992

Two kinds of complement activating (anti-complementary) polysaccharides, which were expected to be immunomodulators were purified from Arecae Pericarpium (the pericarps of Areca catechu), and their action modes have been studied. The active polysaccharides, AC-2-IIIa and AC-2-IIIc from Arecae Pericarpium showed dose-dependent anti-complementary activities on $TCH_{50}$. The anti-complementary activities of AC-2-IIIa and AC-2-IIIc in metal ion-free condition were completely decreased in comparison with control whereas in case of $Ca^{2+}$-free condition, these activities were maintained, considerably. Also AC-2-IIIa and AC-2-IIIc showed relatively potent alternative complement pathway activities. Furthermore, after incubation of the normal human serum with polysaccharide of Arecae Pericarpium in the absence of $Ca^{2+}$ ion, a cleavage of C3 in the serum was found to have occurred through immunoelectrophoresis (IEP) with anti-human C3. Also, from the results of IEP using anti-human whole serum, the ratios of the height of 3rd peak to ${\alpha}2-M$ peak by AC-2-IIIa and AC-2-IIIc proved to be $1.50{\pm}0.04$ and $1.22{\pm}0.08$, respectively. These results indicate that the modes of complement activation by AC-2-IIIa and AC-2-IIIc from Arecae Pericarpium are via both the classical pathway and the alternative pathway.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.190-193
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• 2014

CMP-Neu5Ac synthetase is a key enzyme for the synthesis of CMP-Neu5Ac, which is an essential precursor of sialylated glycoconjugates. For the soluble expression of the CMP-Neu5Ac synthetase gene (neuA) from Escherichia coli K1, various heat shock proteins were co-expressed in E. coli BL21 (DE3) Star. In order to do this, a pG-KJE8 plasmid, encoding genes for GroEL-ES and DnaK-DnaJ-GrpE, was co-transformed with neuA and was expressed at $20^{\circ}C$ by the addition of 0.01 mM IPTG and 0.005 mg/ml L-arabinose. The co-expression of a variety of heat shock proteins resulted in the remarkably improved production of soluble CMP-Neu5Ac synthetase in E. coli.

• Journal of Food Hygiene and Safety
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• v.13 no.4
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• pp.370-376
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• 1998

The extraction yield of MeOH extract of green teas, oolong tea and black tea were 3 to 5, 4 to 5, and 5 to 7 fold higher than those of EtOH and EtAC extract, respectively. The amount of total catechins of EtAC extract of the black tea, and of the green teas and oolong tea were three- and two-fold higher than that of EtOH or MeOH extract of the corresponding teas, respectively. The antioxidative activities of EtOH, MeOH and EtAc extract were considerably higher than that of BHT and $dl-{\alpha}-tocopherol$ at 200 ppm level. The antioxidative activities of EtOH and MeOH extract at 200 and 500 ppm level, and of EtAc extract at 200 ppm level varied depending on the type of tea as follows : green tea I > green tea II > green tea III > oo-long tea> black tea. The antioxidative activity increased as the content of EGC increased. But the antioxidative activity of MeOH extract at 1000 ppm level, and of EtAc extract at 500 and 1000 ppm level were not affected by the content of EGC and EGCG.