• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.285-291
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• 1996

The effect of various packaging methods on Kimchi quality was investigated in order to develop the packaging techniques for preventing commercial Kimchi Products from ination and explosion due to fermentative gas evolved during storage and distribution. Kimchi was packaged in different methods; atmospheric (AP), check-valved (CV), double (DP) and vacuum (VP) packaging. The quality of Kimchi during storage at $10^{\circ}C$ was evaluated ill terms of gas composition, free volume, pH, titratable acidity, color index, lactic acid bacteria and sensory properties. $O_2$ concentration decreased to about 1% at $6{\sim}8$ days of optimal ripening time in all packages except DP, in which it remained around 20%. $CO_2$ concentration reached $70{\sim}90%$ after $6{\sim}8$ days in AP, CV and DP, while it stayed around 10% in DP. The free volume in AP had typical sigmoidal curve similar to $CO_2$ concentration changes. It remained almost constant in CV and DP, but started to increase at the late stage of storage In VP. There was no significant influence of packaging methods on the other quality attributes such as pH, titratable acidity, color index (L.b/a), lactic acid bacteria count and sensory evaluation score. As results, it could be proposed to employ CV and DP method as the effective packaging techniques for preventing commercial Kimchi products from inflation.

• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.1 s.20
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• pp.59-68
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• 2006

Flow separation of recirculation zone by increasing of flow and change of its direction at confluence results in backwater due to conveyance reduction. The hydraulic characteristics of flow separation are analysed by experimental results of flow ratios of tributary and main streams and approaching angles. The boundary of flow separation by dimensionless length and width is defined by the streamline of zero and this definition agrees well to the existing investigation. Because flow separation doesn't appear in small flow ratio and approaching angle of $30^{\circ}$, the equation of flow separation with flow ratio and approaching angle is provided. In flow separation consideration and comparing with previous results, the existing equations of dimensionless length and width ratios by function of approaching angle, flow ratio, and downstream Froude number are modified and also contraction coefficient and shape factor are analysed. Dimensionless length and width ratios are proportional to the flow ratio and approaching angle. In analysis of water surface profiles, the backwater effects are proportional to the flow ratio and approaching angle and the magnitude at outside wall is greater than that of inside wall of main stream. The length, $X_l$ from the beginning of confluence to downstream of uniform flow, where the depth is equal to uniform depth, is characterized by width of stream, flow ratio, approaching angle, and contraction coefficient. The ratios between maximum water depth by backwater and minimum depth at separation are analysed.

• Korean journal of applied entomology
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• v.41 no.1
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• pp.27-32
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• 2002

Biological control of thrips with a predatory bug species, Orius sauteri Poppius, was evaluated in an eggplant greenhouse, To study the biological control strategy of thrips. three Plots were established: Orius sauteri released plot without pesticide treatment (NRT), pesticide treated plot (PAT), and natural enemy removed plot (RNT) The nymphs of O. sauteri were found on the upper side of leaves in NRT at 21 days after the first release of O. sauteri. The density of thrips were dropped and maintained at lower level in NRT than in RNT. Average damage index of NRT, PAT and RNT was 1.35, 1.21 and 2.90 and the percentage of damaged fruit ratio of those was 70.3, 68.6 and 99.0%, respectively. The damage index and percentage of damaged fruit in NRT were slightly higher than those of PAT, but much lower than in RNT. Taylor's band Iwao's $\beta$ were greater than 1 for both populations. indicating aggregated distribution. Spatial coincidence index of O. sauteri was high most of the time even at low densities of both populations. The refuge index for thrips decreased as O. sauteri density increased. Results of this study suggest that O. sauteri is a promising natural enemy for thrips control on eggplant.

• Korean journal of food and cookery science
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• v.14 no.1
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• pp.1-8
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• 1998

The characteristics of Kimchi, associated with proceeding velocity of fermentation, and microbial changes, were investigated during fermentation where kimchi were prepared by the addition of different kinds of minor ingredients. In all samples, total acidity increased, and the pH and total reducing sugar content decreased as the fermentation proceeded. Redox potentials decreased from early to middle fermentation period but thereafter increased and had the lowest value at optimum ripening stage. The counts of total viable and lactic acid bacteria increased rapidly at the begining and decreased slowly. These bacterial counts of kimchi samples containing ginger, red pepper powder, and mixture of all minor ingredients were higher than those of other samples. The number of Leuconostoc mensenteroides reached the maximum at the optimum fermenting stage, Lactobacillus plantarum appeared at the time when Leu. mesenteroides reduced. All these phenomena were observed earlier in the samples containing raw red pepper and later in the samples added garlic than in other samples. It is suggested that garlic is the ingredient which improved storage capacity by prolonging fermentation period by lactic acid bacteria beneficial to less acidification, and ginger and red pepper powder are materials which gave better taste to kimchi by stimulating the growth of Leu. mesenteroids. And redox potential was an useful indicator in choosing optimum ripening time during fermentation.

• Journal of the Korea Concrete Institute
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• v.24 no.3
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• pp.285-292
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• 2012

Fixed connection is generally used for beam and column connections of concrete structures, but significant damages at the connection due to severe earthquakes have been reported. In order to reduce damages of the connection and improve seismic performance of the connection, several innovative connections have been suggested. One newly proposed connection type allows a rotation of the connection for applications in rotating or rocking beams, columns, and shear walls. Such structural elements would provide a nonlinear lateral force-displacement response since their contact depth developed during rotation is gradually reduced and the stress across the sections of the elements is non-linearly distributed around a contact area, which is called an elastic hinge region in the present study. The purpose of the present study is to define the elastic hinge region or length for the rocking columns, through investigating the cross-sectional stress distribution during their lateral behavior. Performing a finite element analysis (FEA), several parameters are considered including axial load levels (5% and 10% of nominal strength), different boundary conditions (confined-ends and cantilever types), and slenderness ratios (length/depth = 5, 7, 10). The FEA results showed that the elastic hinge length does not directly depend on the parameters considered, but it is governed by a contact depth only. The elastic hinge length started to develop after an opening state and increased non-linearly until a rocking point(pre-rocking). However, the length did not increase any more after the rocking point (post-rocking) and remained as a constant value. Half space model predicting the elastic hinge length is adapted and the results are compared with the numerical results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.300-306
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• 1989

This study was investigated to determine the functional properties of mugbean protein isolates(MPI) from sunhwa-nogdu(SH) and conventional mungbean varieties(C). MPI were prepared from defatted mungbean flour by extraction with 0.1N NaOH, precipitation at pH 4.5, washing of dispersed precipitate with buffer solution and distilled water, and subsequent freeze-drying. Crude protein content of MPI was in the range of $88.7{\sim}91.3%$. The lowest solubility was recorded at $pH\;4{\sim}5$, whereas the best buffering action was in the range of $5.5{\sim}7.5$. On the other hand, gelation of MPI was found to depend on the protein concentration. In the cases of foamability, % volume increase and specific volume were higher for 10 min. with a good whipping ability. And also, the MPI properties of two varieties of SH and C were compared and discussed.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.382-388
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• 2014

This study selected five observational stations in the normal direction of Jinu-do(island) shoreline and observed water temperature, electrical conductivity and pressure from March, 2012 to January, 2013(about 11 months) and attempted to see the variation characteristics of ground watertable. This study wants to know : 1) External environment force factors(tide, climate, wave etc.) affecting ground watertable variation through time series and correlation analysis. 2) Spatial variations of ground watertable and electrical conductivity change by storm event. First, we found that the station at the intertidal zone was strongly affected by wave and tide level and the stations at sand dune and vegetation zone was affected by precipitation and tide level through time series data and correlation analysis. Second, during the storm event, we found that ground watertable and electrical conductivity are stabilized at the start line of sand dune and vegetation zone and transition zone between freshwater layer and seawater layer exists in the experiment area and is about 50~70 m from coastline of the south side of Jinu-do(island).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.3
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• pp.303-309
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• 2016

The human skins had a lot of changes as aging. The synthesis of collagens and elastic fibers were reduced and the expression of matrix metalloproteinase (MMPs) was increased in the dermis. These changes have been known to be responsible for skin wrinkle formation. In this study, we tried to develop pre-indicator of inner skin aging, and investigated the effect of the cream product containing Gynostemma pentaphyllum gypenoside fraction (Gynostemma pentaphyllum gypenoside cream). 21 ~ 34 years old 52 Korean female volunteers without crow's feet were chosen for this clinical study. The starting point of inner skin aging was confirmed through dermal density measurement, even though outside skin wrinkles were not observed. In addition, 4 and 8 weeks treatment of G. pentaphyllum gypenoside cream significantly increased age-related reduction of dermal density. These results suggest that the evaluation of dermal density can be used as pre-indicator of skin aging. Furthermore, G. pentaphyllum gypenoside fraction is a potential anti-wrinkle agent for prevention and treatment of skin aging.

• Journal of the Korean Magnetics Society
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• v.5 no.4
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• pp.281-286
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• 1995

In order to study the effect of additives $SiO_{2}$ on the magnetic properties of hexaferrite sheet magnet, we used X-ray diffractometer, Mossbauer spectrometer, and VSM magnetometer. We have prepared $Ba_{0.25}Sr_{0.75}Fe_{12}O_{19}$ green sheets by the Dr. Blade method. Most of samples have a magnetoplurnbite crystal structure of typical M-type hexaferrite. The lattice parameters are found not to be affected by the addition of $SiO_{2}$. ${\alpha}-Fe_{2}O_{3}$ phase develops above $SiO_{2}$ 2.0 wt.%. Isomer shifts indicate that the valence of Fe ions is trivalent. Curie temperatures decrease slightly with increasing $SiO_{2}$ concentrations. It means that the $Si^{4+}$ subsitution for 12k-site $Fe^{3+}$ has an effect on the superexchange interactions Fe-O-Fe, which change the distance and the angle between cations and anions. It was suggested that ${\alpha}-Fe_{2}O_{3}$ phase results from the excessive Fe produced by subsituting $Si^{4+}$ for $Fe^{3+}$. Based upon the results of $Ba_{0.25}Sr_{0.75}Fe_{12}O_{19}$ added with $SiO_{2}$, we concluded that $H_{c}$, $M_{s}$ and $M_{r}$ depend more strongly on the microstructure chracteristics than on the cation substitution.

• Culinary science and hospitality research
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• v.21 no.1
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• pp.267-280
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• 2015

This study was carried out to evaluate the quality characteristics of Takju, Yakju, Spirit made by various cereal Nuruks which were made by Jokuk(whole wheat), Bunkuk(wheat flour), Maekkuk(whole barley). pH, Brix, cell number of yeast, alcohol content, flavors, organic acid, and sensory evaluation of brews were employed to analyze current study. Results showed that pH value of brews during fermentation decreased, while Brix value increased. In addition, alcohol contents increased up to 11 day's fermentation, but there were no significant differences among Jokuk, Bunkuk and Maekkuk(p<0.05). Cell numbers of yeast dramatically increased up to 5 day's fermentation, and then decreased. After 13 day's fermentation cell numbers of yeast were similar among Jokuk, Bunkuk and Maekkuk. In terms of analysis of flavor components, acetone and n-amyl alcohol were not detected in all brews, however fusel oil level was 494.65 mg/L in Maekkuk, and 525.4 mg/L in Bunkuk. Lactic acid showed the highest level in organic acid analysis. Furthermore, Jokuk and Maekkuk showed highest score in Takju, Maekkuk showed highest score in Yakju in sensory evaluation, although Jokuk, Bunkuk, and Maekkuk revealed similar score in spirit.