• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1361-1363
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• 1997

Zinc oxide-based MOV was fabricated with $SiO_2$ additive ranging from 0.5 to 4.0 mol%, and the microstructure and electrical characteristics were investigated. $Zn_2SiO_4$ phase formed by $SiO_2$ additive was distributed at ZnO grains, grain boundaries, and multiple grain junctions. As the content of $SiO_2$ additive increases, average grain size decreased from 40.6 to $26.9{\mu}m$ due to the Pinning effect by $Zn_2SiO_4$ at grain boundaries Breakdown voltage and nonlinear exponent increased, and leakage current decreased in the range of $11.2{\sim}6.14{\mu}A$ with an increasing $SiO_2$. Donor concentration and interface state density decreased, and barrier height increased in the range of $0.71{\sim}1.04eV$ with an increasing $SiO_2$. While, as the content of $SiO_2$ additive, apparent dielectric constant decreased, peak frequency of dissipation factor decreased in the range of $6.45{\times}10^5{\sim}3.00{\times}10^5Hz$, and dissipation peak was $0.31{\sim}0.22$ at Peak frequency.

• Korean Journal of Child Studies
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• v.15 no.1
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• pp.5-21
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• 1994

The purpose of this study was to develop a scale for evaluation of early childhood programs in Korea. The procedures included content validation and a pilot test. A total of 192 items in 10 major areas was developed based on the review of literature and discussions with professionals in early childhood education. The 10 areas include: scheduling, curriculum, interation, physical environment, materials, nutrition, health and safety, administration, staff qualifications, relationships with parents, and evaluation. The pilot scale was administered to 428 classroom teachers and directors, and 47 college professors in early childhood education. The items were rated on a 3-point scale in terms of importance as evaluation criteria. The methods for data analysis included item means and standard deviations for content validation, Cronbach ${\alpha}$ for reliability, and factor analysis for construct validity. Most items in 10 areas were rated as moderate to highly important (average 2.3), especially items in curriculum and staff qualifications. Two factors emerged from the data: institutional management, and curricular planning and implementation. The Cronbach ${\alpha}$ levels were .70 or higher in most areas, but the range covers from .48 to .91. Based on the pilot data, 143 items were selected for the second year study.

• Journal of Ginseng Research
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• v.6 no.2
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• pp.168-203
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• 1982

Effects of soil moisture on growth of Panax ginseng, of various factors on soil moisture, and of moisture on nutrition, quality, physiological disorder, diseases and insect damage were reviewed. Optimum soil moisture was 32% of field capacity with sand during seed dehiscence, and 55-65% for plant growth in the fields. Optimum soil moisture content for growth was higher for aerial part than for root and higher for width than for length. Soil factors for high yield in ginseng fields appeared to be organic matter, silt, clay, agreggation, and porosity that contributed more to water holding capacity than rain fall did, and to drainage. Most practices for field preparation aimed to control soil moisture rather than nutrients and pathogens. Light intensity was a primary factor affecting soil moisture content through evaporation. Straw mulching was best for the increase of soil moisture especially in rear side of bed. Translocation to aerial part was inhibited by water stress in order of Mg, p, Ca, N an Mn while accelerated in order of Fe, Zn and K. Most physiological disorders(leaf yellowing, early leaf fall, papery leaf spot, root reddening, root scab, root cracking, root dormancy) and quality factors were mainly related to water stress. Most critical diseases were due to stress, excess and variation of soil water, and heavy rain fall. The role of water should be studied in multidiciplinary, especially in physiology and pathology.

• Food Science and Preservation
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• v.1 no.2
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• pp.81-86
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• 1994

This study examined the quality change of red peppers during storage at various temperatures and humidities. It was observed that red peppers showed mold at aw 0.75(>25% water content), discoloration at aw 0.33(<10%) and browning at aw 0.75(>19%). The most ideal condition of the storage for red peppers was a 13∼15% water content and 60${\pm}$5% RH. The storage life for whole red peppers were 2.0 months at 40$^{\circ}C$, 13.6 months at 25$^{\circ}C$, 27.3 months at 15$^{\circ}C$, 30.0 months at 10$^{\circ}C$, and 65.0 months at -3$^{\circ}C$. During any storage period above, level of capsanthin, browning and capsaicin were changed for whole peppers. Browning appeared to be a crucial factor for marketable quality of stored red peppers. It was found that the level of capsaicin & capsanthin have a miner relationship with marketable quality for consumer. Storing red peppers in nitrogen and vacuum atmosphere packing condition was found to be better than storing them in air at various temperatures in terms of storage life and quality maintenance. The nitrogen gas packaged red peppers kept longer shelf life and better quality compared with vacuum packaging.

• Food Science and Preservation
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• v.24 no.4
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• pp.517-523
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• 2017

Hovenia dulcis fruit powder (HFP) has shown diverse functional activities; thus, it is rational to incorporate HFP into suitable food products with enhanced nutritional and functional quality, and their incorporation into bakery products such as cookies could be a good alternative for the increase of consumption. The aim of this study was to examine the effect of HFP addition on the quality characteristics of cookies. The pH of cookie doughs ranged from 5.80-6.34, with no remarkable differences by HFP addition. Density of cookie doughs significantly decreased upon addition of HFP (p<0.05), but there were no significant differences among samples added with HFP (p>0.05). Moisture content and spread factor of cookies significantly increased with higher content of HFP in the formulation (p<0.05). For color values of cookie surface, $L^*$ and $b^*-values$ decreased while $a^*-value$ increased as a result of HFP substitution (p<0.05). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging activities were significantly increased (p<0.05) with higher substitution of HFP, showing a positive correlation. Hedonic sensory results indicated that cookies supplemented with 4% HFP received the most favorable acceptance scores for sensory attributes. Overall, HFP-added cookies could be developed with improved physicochemical qualities without sacrificing consumer acceptability.

• YAKHAK HOEJI
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• v.34 no.3
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• pp.155-160
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• 1990

An oral adhesive tablet of acyclorir [9-(2-hydroxyethoxymethyl) guanine] for herpetic stomatitis was prepared and its physical properties were evaluated. 300 mg weighed tablets containing 30 mg of acyclovir were prepared with six kinds of polymers from direct compression, and the stickiness, fracture resistance and dissolution in pH 6.8 buffer solution were tested. HPMC and MC showed good stickiness and fracture resistance, and their dissolution rates were significantly different from each other. Three factors-HPMC:MC ratio, acyclovir content, compression force-were chosen as an important factor of manufacture and factorial analyses for these three factors were carried out. Eight kinds of formulations from different combination of three factors were prepared and tested in stickiness, fracture resistance and dissolution in pH 6.8 buffer solution. Dissolution rate was significantly affected by polymer ratio, fracture resistance was affected by compression force, and stickiness was not significantly affected by acyclovir content and polymer ratio.

• YAKHAK HOEJI
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• v.47 no.3
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• pp.148-153
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• 2003

Skin moisture is an important factor in skin health. Measurement of moisture content can provide diagnostic information on the condition of skin. In this study, a portable near-infrared (NIR) system was newly integrated with a photo diode array detector that has no moving parts, and this system has been successfully applied for the evaluation of human skin moisture. Diffuse reflectance spectra were collected and transformed to absorbance using 1 nm step size over the wavelength range of 1100 nm to 2200 nm. Partial least squares regression (PLSR) was applied to develop a calibration model. For practical use for the evaluation of human skin moisture, the PLS model for human skin moisture was developed in vivo using the portable NIR system on the basis of the relative water content values of stratum corneum from the conventional capacitance method. The PLS model showed a good correlation. The calibration with the use of PLS model predicted human moisture with a standard error of prediction (SEP) of 3.5 at 1120∼1730 nm range. This study showed the possibility of skin moisture measurement using portable NIR system.

• Food Science of Animal Resources
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• v.34 no.6
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• pp.757-762
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• 2014

The object of this study was to investigate the difference in physical and sensory properties of various premium ice creams. The physical properties of the various ice creams were compared by manufacturing brand. The water contents of the samples differed, with BR having the highest value at 60.5%, followed by NT and CS at 57.8% and 56.9%, respectively. The higher the water content, the lower Brix and milk fat contents in all samples. The density of the samples showed almost similar values in all samples (p>0.05). The viscosity of each ice cream had no effect on the water content in any of the brands. Before melting of the ice cream, the total color difference was dependent on the lightness, especially in the vanilla ice cream, owing to the reflection of light on the surface of the ice crystals. The CS product melted the fastest. In the sensory test, CS obtained a significantly higher sweetness intensity score but a lower score for color intensity, probably due to the smaller difference in total color, by which consumers might consider the color of CS as less intense. From this study, the cold chain system for ice cream distribution might be important to decide the physical properties although the concentration of milk fat is key factor in premium ice cream.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.04a
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• pp.26-27
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• 1995

Most of synthetic polymeric membranes used in ultrafiltration, reverse osmosis and microfiltration processes are prepared by phase inversion(or phase separation) technique. In this technique, a homogeneous polymer solution is cast into thin film or hollow fiber shape and then immersed into a nonsolvent coagulant bath. The exchange of solvent and nonsolvent across the interface between casting solution and coagu!ant can make the casting solution phase-separate and form a membrane with a symmetric or asymmetric structure. Because of importance of this technique in membrane field, many investigations have been dedicated to elucidate the mechanism of membrane formation by phase inversion technique.[1-10] These investigation have suggested that the structure formation and permeation properties of phase inversion membrane depend on the variables such as the nature and content of casting solution and coagulant, temperature of casting solution and coagulant, and the diffusional exchange rate of solvent and nonsolvent etc. which can be related to the thermodynamic and kinetic properties of the casting system. The variables such as the nature and content of casting solution can also be the important factor affecting the structure formation and permeation property of the phase inversion membrane.

• Journal of Korean Academy of Nursing
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• v.38 no.6
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• pp.813-821
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• 2008

Purpose: This study was conducted to develop an instrument measuring awareness of osteoporosis. Methods: The process included construction of a conceptual framework, generation of 86 preliminary items, verification of content validity, selection of secondary items, verification of construct validity and extraction of final items. The 86 items were reviewed for content validity by two groups of experts and were tested to evaluate inter item correlation coefficient by two groups of adult women. From June to August 2007, data were collected from 383 adult women who lived in Seoul and provinces in Korea. Data were analyzed by performing item analysis, Varimax factor analysis and Cronbach's alpha. Results: There were 31 items in the final instrument categorized into 5 factors. The factors were labeled as "preventive behaviors (10 items)", "risk factors (5 items)", "characteristics of osteoporosis (6 items)", "improving bone health (5 items)", and "bone physiology (5 items)". Cumulative percent of variance was 60.92% and eigen values ranged from 1.20 to 12.44. Cronbach's alpha was .948 and ranged from .804 to .917. Conclusion: Validity and reliability of the scale are confirmed in this study showing its utility for measuring awareness of osteoporosis for women. Utilization of the scale will also contribute to designing an appropriate prevention program for osteoporosis.