• Journal of Navigation and Port Research
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• v.40 no.6
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• pp.441-450
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• 2016

A pilot scale biostimulation experiment was performed under field conditions to degrade organic pollutants and PAHs (Polycyclic Aromatic Compounds) in contaminated coastal sediment. During the experiment, the seawater temperature around the sediment varied from $16.5^{\circ}C$ to $21^{\circ}C$, while the sediment pH was stable at 8.4-8.5. The experiment was conducted over a one year period with a control group and a sample group with a applied biostimulant composed of acetate, sulfate, and nitrate. Chemical oxygen demand decreased 39% in the control group and 79% in the sample group. Volatile solids were reduced from 15 to 7 g/kg in the control group and 2.5 g/kg in the sample group. Out of the 2-, 3- ,4- ,5-, and 6-rings of the 16 vital PAHs, the compound including naphthalene (2-ring), took 2 months to degrade completely, while the degradation efficiency was 55.6% in the control group during the same period. In the case of the 3-ring and 4-ring PAHs, complete degradation in the sample and 46% - 100% degradation in control was observed after one year of the experiment. The 5-ring and 6-ring PAHs were degraded to about 77%-100% in the sample group and 26%-87% in the control group during the one year of the experiment. The study results show that biostimulation is a very effective method to improve the degradation rate of organic pollutants and PAHs (Polycyclic Aromatic Compounds) in contaminated coastal sediment.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.3
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• pp.254-259
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• 2014

A pressurized heavy water reactor (PHWR) core has 380 fuel channels contained and supported by a horizontal cylindrical vessel known as the calandria, whereas a pressurized water reactor (PWR) has only a single reactor vessel. The pressure tube, which is a pressure-retaining component, has a 103.4 mm inside diameter ${\times}$ 4.19 mm wall thickness, and is 6.36 m long, made of a zirconium alloy (Zr-2.5 wt% Nb). This provides support for the fuel while transporting the $D_2O$ heat-transfer fluid. The simple tubular geometry invites highly automated inspection, and good approach for all inspection. Similar to all nuclear heat-transfer pressure boundaries, the PHWR pressure tube requires a rigorous, periodic inspection to assess the reactor integrity in accordance with the Korea Nuclear Safety Committee law. Volumetric-based nondestructive evaluation (NDE) techniques utilizing ultrasonic and eddy current testing have been adopted for use in the periodic inspection of the fuel channel. The eddy current testing, as a supplemental NDE method to ultrasonic testing, is used to confirm the flaws primarily detected through ultrasonic testing, however, eddy current testing offers a significant advantage in that its ability to detect surface flaws is superior to that of ultrasonic testing. In this paper, effectiveness of flaw detection and the depth sizing capability by eddy current testing for the inside surface of a pressure tube, will be introduced. As a result of this examination, the ET technique is found to be useful only as a detection technique for defects because it can detect fine defects on the surface with high resolution. However, the ET technique is not recommended for use as a depth sizing method because it has a large degree of error for depth sizing.

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.448-455
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• 2004

Changes in quality characteristics of Bijijang (fermented soybean curd residus) prepared at $35^{\circ}C\;and\;40^{\circ}C$ for 0, 12, 24, 36, and 48 hr were investigated. Acidity of Bijijang increased, whereas pH and Hunter's color values decreased during fermentation. Immediately after Bijijang preparation, ${\alpha}-and\;{\beta}-amylase$ activities were very low, ${\beta}-Amylase$ activity during fermentation increased rapidly, with those fermented at $40^{\circ}C$ higher than at $35^{\circ}C$. Neutral pretense activity was significantly higher than acidic pretense activity, and increased gradually after 12 hr. Change in total nitrogen content in Bijijang was insignificant, whereas contents of amino-type and water-soluble nitrogens increased significantly during fermentation. Major free amino acids of Bijijang were Arg, Pro, Glu, Thr, Ser, and Lys at initial fermenting stage, and, as fermentation progressed, contents of Cys, Met Glu, Ile, Leu, and Phe increased. Reducing sugar contents of Bijijang fermented at $40^{\circ}C$ were higher than those fermented at $35^{\circ}C$. Sucrose content decreased and glucose content increased. Glucoside (genistin and daidzin) contents decreased and aglycone (genistein and daidzein) contents increased during preparation of Biji and fermentation of Bijijang. Contents of free sugars and isoflavones were higher in Bijijang fermented at $40^{\circ}C$ than at $35^{\circ}C$. Based on these results, fermentation at $40^{\circ}C$ for 48 hr was determined to be optimum fermentation condition for Bijijang.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.128-134
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• 2012

Foot and mouth disease (FMD) is one of the most notorious and contagious viral diseases afflicting cloven-hoofed animals. In this study, the physicochemical properties of leachate from a FMD landfill site at 773-1, Waryong, Andong, Korea and the ground water from 777, Waryong, Andong, Korea, were analyzed for 1 year from December $10^{th}$ 2010 to November $17^{th}$ 2011. The leachate was collected from the FMD landfill site during March, May, July, September and November, 2011 and changes in pH, brix, water content, insoluble solids, crude proteins, crude lipids, total and reducing sugars and ash content were determined. Considering the annual profiles of temperature and rainfall at the FMD landfill site, the dramatic changes in the physicochemical properties of the leachate from March to July, and especially from May to July, such as increases in pH, and a rapid reduction of brix and organic matter, may be closely linked to the growth of microorganisms in the leachate. The sharp decreases in the concentration of biominerals, such as Mg, Ca, and Fe from 1073, 4311 and 56.2 ppm in March to 151, 78, and 0.1 ppm in November, further suggest that decreases in organic matter in the leachate result from degradation by microorganisms originating from the intestines of the livestock. Analysis of the profiles of the organic materials in the leachate revealed that the properties of the leachate were similar to those of excremental matter-derived water. These results could be applied to a number of fields for the analysis of organic matter behavior, the development of the degradation process, and risk analysis in the environment for hygiene and food industries, of leachate from FMD landfill sites.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.211-218
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• 2003

For the Exp. 1, a total of sixty pigs (10.57$\pm$0.30kg average initial body weight) were used in a 15-d growth assay to determine the effect of dietary $\alpha$-1,6-galactosidase and $\beta$-1,4-mannanase on growth performance and nutrient digestibility. Dietary treatments included 1) CON (corn-dried whey-SBM based diet), 2) EC0.1 (CON diet+0.1% enzyme complex of $\alpha$-1,6-galactosidase and $\beta$-1,4-mannanase). Through the entire experimental period, gain/feed of pigs fed EC0.1 diet was higher (0.43 vs 0.52) than that of pigs fed CON diet (P<0.05). Pigs fed EC0.1 diet showed significant (P<0.05) improvement in dry matter (74.82% vs 82.41%) and nitrogen (70.59% vs 77.88%) digestibilities compared to pigs fed CON diet. For the Exp. 2, a total of thirty six pigs (22.30$\pm$0.45kg average initial body weight) were used in a 30-d growth assay to determine the effects of dietary $\alpha$-1,6-galactosidase and $\beta$-1,4-mannanase in low energy diet on growth performance and nutrient digestibility. Dietary treatments included 1) AME (adequate ME diet), 2) AME+EC0.1 (AME diet+0.1% enzyme complex) and LME+EC0.1 (low ME diet + 0.1% enzyme complex). Through the entire experimental period, average daily feed intake of pigs fed enzyme complex supplemented diets was higher than that of pigs fed CON diet (P<0.05). Also, pigs fed AME+EC0.1 diet showed significant (P<0.05) increase in ADFI (1,401g vs 1,733g) compared to pigs fed CON diet. Pigs fed enzyme complex supplemented diet showed significant (P<0.05) improvement in dry matter and nitrogen digestibilities compared to pigs fed CON diet. In conclusion, the results obtained from these feeding trials suggest that the supplementation of $\alpha$-1,6-galactosidase and $\beta$-1,4-mannanase was an effective means for improving growth performance and dry matter and nitrogen digestibilities in nursery and growing pigs.

• Applied Biological Chemistry
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• v.26 no.4
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• pp.222-230
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• 1983

This study was designed to develop a process for the immobilization of xylose isomerase(D-xylose ketol isomerase, EC 5.3.1.5) from Streptomyces griseolus previously isolated by the authors and its application on a pilot plant scale for the production of high fructose corn syrup. The biomass which has endo-excreted xylose isomerase was homogenized under a pressure of $500kg/cm^2$ and 90.8% of the enzyme recovery of the native activity was obtained as compared to 54.7% recovery by the lysozyme treatment. Ionic bonding method was adopted for the enzyme immobilization due to its many reported merits. It was found that the porous resins such as Diaion HP 20, Duolite A-7, Amberlite IRA 93 and 94 were effective in immobilizing the enzyme. In addition, it was disclosed that the regeneration form of $BO_4--$ is effective for Amberlite IRA 93 and $HCO_3-$ for Diaion HP 20. Optimal immobilization condition for Amberlite IRA 93 was pH 8.0 and $55^{\circ}C$ yielding 80.6% of immobilization. Activity decay test showed half life of the immobilized enzyme with Amberlite IRA 93 was more than 24 days at $65^{\circ}C$. The carrier was evaluated to be resuable and its result showed the relative immobilization yields were 98.2, 93.3, 90.7 and 87.5%, respectively at second, third, forth and fifth rebinding test of the enzyme on Amberlite IRA 93. Optimal temperature of the immobilized enzyme was slightly lowered and the range widened to $60\sim70^{\circ}C$, while optimal pH moved toward $8.0\sim8.3$ in its isomerization reaction. The trial production result of high fructose corn syrup in pilot scale immobilization showed that one liter of immobilized xylose isomerase (350 IXIU/ml-R) is capable producing about 293l high fructose corn syrup(75% dry substance) in 30 days.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.4
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• pp.72-86
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• 2014

This study was conducted to investigate the effects of mulching of easily-decomposable organic materials including rice powder and corn starch on rice paddy fields. The treatments were including seven mulching materials each consisted of rice powder [Rice], starch with black color [Starch-B] and transparent [Starch-T] and stone powder [Stone], and conventional vinyl [Conventional], no-mulching without herbicide [Control-O] and no-mulching with herbicide [Control-C]. Rice growth and yield were different among the treatments; the highest yields were observed for [Rice] ($6.51ton\;ha^{-1}$) and [Conventional] ($6.47ton\;ha^{-1}$) followed by [Starch-T] ($6.25ton\;ha^{-1}$) and [Stone] ($6.20ton\;ha^{-1}$) which is comparable to the [Control-C] ($6.15ton\;ha^{-1}$). However, [Starch-B] showed lower rice yield ($4.93ton\;ha^{-1}$) than the [Conventional] or [Control-C]. Mean soil temperature ranged form 23.6 to $24.1^{\circ}C$ with the highest temperature for [Rice] treatment, and cumulative soil temperature was also significantly higher in the [Rice] treatment. Among the soil parameters, electrical conductivity, organic matter content, and phosphorus concentration were also different among the treatments. The amount of earthworm casting was higher for [Rice] treatment ($17.7kg\;m^{-2}$) compared to the others ($5.5{\sim}9.8kg\;m^{-2}$). It was suggested that mulching of rice fields with organic materials containing rice powder is better than others in respected to rice yield and earthworm activity.

• Journal of Astronomy and Space Sciences
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• v.22 no.1
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• pp.1-12
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• 2005

The Korean VLBI Network (KVN) will open a new field of research in astronomy, geodesy and earth science using the newest three Elm radio telescopes. This will expand our ability to look at the Universe in the millimeter regime. Imaging capability of radio interferometry is highly dependent upon the antenna configuration, source size, declination and the shape of target. In this paper, imaging simulations are carried out with the KVN system configuration. Five test images were used which were a point source, multi-point sources, a uniform sphere with two different sizes compared to the synthesis beam of the KVN and a Very Large Array (VLA) image of Cygnus A. The declination for the full time simulation was set as +60 degrees and the observation time range was -6 to +6 hours around transit. Simulations have been done at 22GHz, one of the KVN observation frequency. All these simulations and data reductions have been run with the Astronomical Image Processing System (AIPS) software package. As the KVN array has a resolution of about 6 mas (milli arcsecond) at 220Hz, in case of model source being approximately the beam size or smaller, the ratio of peak intensity over RMS shows about 10000:1 and 5000:1. The other case in which model source is larger than the beam size, this ratio shows very low range of about 115:1 and 34:1. This is due to the lack of short baselines and the small number of antenna. We compare the coordinates of the model images with those of the cleaned images. The result shows mostly perfect correspondence except in the case of the 12mas uniform sphere. Therefore, the main astronomical targets for the KVN will be the compact sources and the KVN will have an excellent performance in the astrometry for these sources.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.302-307
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• 2002

To investigate difference of components changes in salt-fermented anchovy, Engaulis japonicus sauce during 18 months fermentation by tank size, various chemical properties were examined at 2$\~$3 months intervals. The contents of total and amino nitrogen, total ATP related compounds increased gradually during 18 months of fermentation, and showed higher content in salt-fermented anchor sauce produced by large tank scale (LTS) product than those of small tank scale (STS) product during fermentation. Hypoxanthine and uric acid were the most abundant in ATP related compounds, ranging from $81.1\%$ to $90.4\%$, The cross point of inosine (HxR) + hypoxanthine (Hx) and uric acid was faster in LTS with 10.3 months fermentation than in STS with 12.6 months fermentation. After 18month of fermentation, the LTS was rich in free amino acids, such as glutamic acid, alanine, aspartic acid, valine, Iysine in that order. On the other hand, the STS was rich in free amino acids, glutamic acid, aspartic acid, alanine, vsine, valine in that order. Absorbance at 453 nm were higher in STS than in STS, but was no difference the rate of increase during fermentation.

• Microbiology and Biotechnology Letters
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• v.41 no.4
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• pp.449-455
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• 2013

Human skin is constantly exposed to environmental conditions such as UV rays, polluted air, and chemical products. UV rays, in particular, affect skin in many ways causing wrinkles, fine wrinkles, rough skin, and xeroderma through a skin aging process. The purpose of this study was to investigate the anti-wrinkling effect of Juniperus rigida Sieb., derived from a common cedar tree found the world over. Measuring the elastase to investigate wrinkling efficacy, it was shown that at a concentration level of $1,000{\mu}g/ml$ of the two extracts, the water extract exhibited a lower than 10% inhibition activity, while the ethanol extract exhibited a 68.5% inhibition activity. Collagenase inhibition activity in the water extract and ethanol extract were 44.9% in the former and 97.2% in the latter extract, which in the case of the ethanol extract, is similar to ascorbic acid (99.6%). Moreover, measuring the biosynthesis of collagen by fibroblast, a concentration level of $50{\mu}g/ml$ of ethanol extract produced 151.52% of biosynthetic promotion, proving that the ethanol extract acts as a superb anti-wrinkling agent. The result of an investigation conducted on the influence of the ethanol extract on MMP-1 caused by UVA showed that at a concentration level of $1,00{\mu}g/ml$ of the ethanol extract of J. rigida Sieb a 67.1% inhibition activity was noted. At a concentration level of $50{\mu}g/ml$ of the ethanol extract of J. rigida Sieb a 35% and 39% inhibition ratio to MMP-1 protein and mRNA were observed respectively, thereby restraining the appearance of the collagen breakdown enzyme MMP-1 and wrinkle creation by skin photo-aging.