• Korean Journal of Food Science and Technology
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• v.34 no.6
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• pp.1140-1144
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• 2002

Molecular relaxation behaviors of crystalline glucose anhydrous, crystalline glucose monohydrate, and amorphous glucose with different particle sizes were observed by measuring spin-spin relaxation time constant $(T_2)$ at the temperature range of $-20\;to\;110^{\circ}C$ using temperature-controlled low field nuclear magnetic resonance spectroscopy. No change in $T_2$ values of crystalline glucose anhydrous was observed throughout the temperature range, whereas $T_2$ values of crystalline glucose monohydrate and amorphous glucose increased from around $45\;and\;65^{\circ}C$, respectively. These results indicate that molecular mobility of crystalline glucose anhydrous does not change even at temperature higher than $100^{\circ}C$ and that the stability of powdered glucose could be improved by increasing the particle size of materials.

• Membrane Journal
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• v.10 no.4
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• pp.205-212
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• 2000

The true-lPN's based on silicone rubber(SR)rrubbery polymer) and polystyrenc(PS)(glass polymer) were prepared by using the sequential IP!\' method_ The characteristic of permeability of oxygen/nitrogen was investigated with the control of the amount of PSOO-70 wt%) in the true-lPN, As a results of fTlR and N1Vm. the SRIPS membrane was synthesised successfully with the IPN synthetic method, Thermal analysis resulls indicated that the degree of mixing of IPN increased with increase of the amount of PS in the IPN. Regarding the characteristic of gas permeability, the membrane showed a trend of decrease in oxygen permeability as the PS content increased, The oxygen permeability of membrane having 50 wt% of PS. however, increased momentarily, Selectivity, meanwhile, increased slightly as the contents of I'S increased. However, the maximum value of oxygen selectivity, which is 20.6% enhanced Value, was obtained with the membrane containing 50 wt% of PS. This can be explained that the behavior of lPN, i.e. mutual assistance, is pronounced in the membrane having 50 wt% of PS.

• Korean Journal of Health Education and Promotion
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• v.29 no.2
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• pp.47-58
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• 2012

Objectives: The purpose of this study is to analyze contents of beer advertisements in Korea. Research has suggested the influence of alcohol advertisements on viewer's drinking behavior, attitude, and expectancies. Korea's policy on alcohol advertising relies on limited government regulation and self regulation among alcohol industries. This study is expected to lay a foundation for further discussion on regulating alcohol advertising in Korea. Methods: A total of 81 beer advertisements broadcasted between 2008 and 2011 were analyzed. The contents were categorized into themes (22 themes were used), models, and presentation techniques. Results: The themes most frequently appeared in beer advertisements were quality (66.7%), relaxation (44%), camaraderie (41%), and individuality (39.5%), respectively. Analysis of models revealed that most advertisements had more than three models (64.2%), and most of them were in their 20s (68%). As much as 82% of advertisements used celebrity models. Analysis on presentation techniques showed that 91.4% displayed drinking scenes, and 27% displayed gulping down the whole bottle or the glass. Finally, about 10% of ads showed drinking in hazardous situations such as during water sports. Conclusion: The results of the study reflect the minimal regulation of alcohol advertising in Korea. The need for joint effort by legislators, researchers, alcohol industries, and advertising agencies is discussed in order to establish healthier drinking environment.

• Journal of Digital Convergence
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• v.11 no.12
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• pp.685-696
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• 2013

The purpose of the present study is to explore the career development barriers of female doctoral degree holders in education. The study occupied in-depth interview with 42 female doctoral degree holders in education. The results were as followed; First, academic advisor highly influenced the career development female doctoral degree holders through their academic activities. Second, they had experiences regarding glass ceiling effect in workplace. Third, marriage was a critical issue for both of the married and single female doctoral degree holders. Fourth, family and relatives' support positively impact on their career will, and also their strong career goal was beneficial way to break their career barriers. Also, the study suggested contextural factor was very significant on career behavior of female doctoral degree holders. Therefore, policy maker, scholars, and students should have strong attention to female students' career guidance and development in various way. The results of the study discussed in relation to the existing literature, with reference to women's career development and career barriers, and then implication for the future research were suggested.

• Analytical Science and Technology
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• v.14 no.2
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• pp.167-172
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• 2001

The technique that could collect efficiently the hanji fibrous sludge from wastewater using surfactants was developed. When fibrous sludge of which concentration was about 80mg/L, was floated and collected, the optimum concentration of sodium oleate, the pore size of glass filter and the air flow rate were 10mg/L, $5-10{\mu}m$ and 200mL/min., respectively. The behavior of sodium oleate might be interfered by polyvalent cations such as $Ca^{2+}$. But when the concentration of $Ca^{2+}$ was less than 100mg/L, the interference effect did not appear. And when a typical cationic surfactant, cetyltrimethylammonium bromide(CTAB), was used, the collecting yield was less than that of sodium oleate, and the amount of foam was higher than sodium oleate. When 1mg/L of CTAB was added to the hanji sludge sample contained 1mg/L of $PAMID^{(R)}$, a dispersant, fibrous sludge was effectively coagulated, the flotation time was very short and the collecting yield was above 95%. But in the case, sodium oleate was inefficient.

• Journal of Powder Materials
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• v.16 no.5
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• pp.358-362
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• 2009

Ti$_{50}$Cu$_{20}$Ni$_{20}$Al$_{10}$ quaternary amorphous alloy was prepared by high-energy ball milling process. A complete amorphization was confirmed for the composition of Ti$_{50}$Cu$_{20}$Ni$_{20}$Al$_{10}$ after milling for 30hrs. Differential scanning calorimetry showed a large super-cooled liquid region ($\Delta$T$_x$ = T$_x$ T$_g$, T$_g$ and T$_x$: glass transition and crystallization onset temperatures, respectively) of 80 K. Prepared amorphous powders of Ti$_{50}$Cu$_{20}$Ni$_{20}$Al$_{10}$ were consolidated by spark-plasma sintering. Densification behavior and microstructure changes were investigated. Samples sintered at higher temperature of 713 K had a nearly full density. With increasing the sintering temperature, the compressive strength increased to fracture strength of 756 MPa in the case of sintering at 733 K, which showed a 'transparticle' fracture. The samples sintered at above 693 K showed the elongation maximum above 2%.

• Electrical & Electronic Materials
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• v.16 no.9
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• pp.64.2-65
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• 2003

A 4 nm layer of ZrOx (targeted x-2) was deposited on an interfacial layer(IL) of native oxide (SiO, t∼1.2 nm) surface on 200 mm Si wafers by a manufacturable atomic layer chemical vapor deposition technique at 30$0^{\circ}C$. Some as-deposited layers were subjected to a post-deposition, rapid thermal annealing at $700^{\circ}C$ for 5 min in flowing oxygen at atmospheric pressure. The experimental x-ray diffraction, x-ray photoelectron spectroscopy, high-resolution transmission electron microscopy, and high-resolution parallel electron energy loss spectroscopy results showed that a multiphase and heterogeneous structure evolved, which we call the Zr-O/IL/Si stack. The as-deposited Zr-O layer was amorphous $ZrO_2$-rich Zr silicate containing about 15% by volume of embedded $ZrO_2$ nanocrystals, which transformed to a glass nanoceramic (with over 90% by volume of predominantly tetragonal-$ZrO_2$(t-$ZrO_2$) and monoclinic-$ZrO_2$(m-$ZrO_2$) nanocrystals) upon annealing. The formation of disordered amorphous regions within some of the nanocrystals, as well as crystalline regions with defects, probably gave rise to lattice strains and deformations. The interfacial layer (IL) was partitioned into an upper Si $o_2$-rich Zr silicate and the lower $SiO_{x}$. The latter was sub-toichiometric and the average oxidation state increased from Si0.86$^{＋}$ in $SiO_{0.43}$ (as-deposited) to Si1.32$^{＋}$ in $SiO_{0.66}$ (annealed). This high oxygen deficiency in $SiO_{x}$ indicative of the low mobility of oxidizing specie in the Zr-O layer. The stacks were characterized for their dielectric properties in the Pt/{Zr-O/IL}/Si metal oxide-semiconductor capacitor(MOSCAP) configuration. The measured equivalent oxide thickness (EOT) was not consistent with the calculated EOT using a bilayer model of $ZrO_2$ and $SiO_2$, and the capacitance in accumulation (and therefore, EOT and kZr-O) was frequency dispersive, trends well documented in literature. This behavior is qualitatively explained in terms of the multi-layer nanostructure and nanochemistry that evolves.ves.ves.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.5
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• pp.429-438
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• 2003

The effects of fiber orientation on acoustic emission(AE) characteristics have been studied for the unidirectional and satin-weave, continuous glass-fiber reinforced plastic(UD-GFRP and SW-GFRP) tensile specimens. Reflection and transmission optical microscopy was used for investigation of the damage zone of specimens. AE signals were classified as different types by using short time fourier transform(STFT) : AE signals with high intensity and high frequency band were due to fiber fracture, while weak AE signals with low frequency band were due to matrix and interfacial cracking. The feature in the rate of hit-events having high amplitudes showed a process of fiber breakages, which expressed the characteristic fracture processes of individual fiber-reinforced plastics with different fiber orientations and with different notching directions. As a consequence, the fracture behavior of the continuous GFRP could be monitored as nondestructive evaluation(NDE) through the AE technique.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.813-822
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• 1996

In order to reduce carbon dioxide, one of the major greenhouse gases, a new type of copolymer, poly(alkylene carbonate) has been synthesized. The alternating copolymers have been obtained from carbon dioxide and various epoxides with zinc carboxylate as a catalyst. The number-average molecular weight of the polymer is about 50,000 and polydispersity is rather broad(5~10). The polymers are amorphous, and glass-clear materials that exhibit unusually facile and clean thermal decomposition behavior. Complete decomposition with no carbon residue is observed at elevated temperature even in an inert atmosphere. Terpolymers with bulkier epoxides improve the physical properties of the copolymer with simple epoxides. The decomposition properties of the polymer provide versatile applications such as ceramic, metal, and electronic binders and lost-foam casting. Further application of the polymer for the barrier film or the plasticizer will be investigated.

• Tribology and Lubricants
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• v.15 no.3
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• pp.278-286
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• 1999

To predict the behavior of the intravascular micro active endoscope in the real human vascular system, a human mock circulation system was developed. The intravascular micro active endoscope which consists of micro active bending catheter and micro drug infusion catheter was driven in the velocity, Re number and temperature controlled flow. The three SMA (Shape Memory Alloy) zigzag type spring in the micro active bending catheter was heated by the electric current generated by PWM controller, and the shape memory effect made the actuator bend to any direction. The micro drug infusion catheter was driven through the inner hole of the micro active bending catheter. A mock circulation system is shaped from Ascending Arota to Femoral artery according to a human data (the data contains many vascular sizes and hydrographs of many control points). We developed a vascular model with glass and silicone tubes, and set the flow system with circulation parts, flow settling parts, and lots of valves. The heater and heat-controller was added to the How system to centre! the temperature of the How at 36.5$^{\circ}C$. The result showed that the developed intravascular micro active endoscope could be induced to any point in the vascular model.