• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.10
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• pp.1525-1530
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• 2015

Doenjang made with various concentrations of salt solution such as 13, 14, 15, 16, 17, and 18% for making low-salt Doenjang. Physicochemical and sensory characteristics of Doenjang made with various concentrations of salt solution were analyzed. As a result, salt contents of Doenjang made with various concentrations of salt solution were 6.09~13.47%. Amino-type nitrogen showed a higher value when prepared with lower salt solution. The pH value increased with lower concentration of salt solution, whereas total acidity decreased with lower concentration of salt solution. The pH values and total acidity of Doenjang made with more than 16% salt solution were not statistically different. The reducing sugar content ranged from 1.39~6.30 mg/g, and higher salt content was associated with higher reducing sugar content. In the sensory descriptive analysis, Doenjang had the most salty taste at a salt concentration of 18%, whereas Doenjang at concentrations of 15%, 16%, and 17% did not show any statistical differences. In the consumer acceptance test, Doenjang made with 17% and 18% salt solution showed the highest score, followed by Doenjang made with 15% and 16% salt solution. In conclusion, the salty taste of Doenjang made with 16% salt solution might be used to make low-salt Doenjang. However, consumer acceptance of these Doenjangs was lower than that of Doenjang made with 17% and 18% salt solution.

• Journal of the Korea Organic Resources Recycling Association
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• v.10 no.2
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• pp.132-139
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• 2002

This study was carried out to investigate the effects of aging and soil texture on composting of diesel-contaminated soil. The soils used for this study were silt loam and sand. Target contaminant, diesel oil, was spiked at 10,000mgTPH/kg of dry soil. Aging times of diesel-contaminated soils were 15days and 60days, respectively. Fresh diesel-contaminated soil was also investigated. Moisture content was controlled to 70% of soil field capacity. Mix ratio of soil to sludge was 1:0.3 as wet weight basis. Temperature was maintained at $20^{\circ}C$ Volatilization loss of TPH was below 2% of initial concentration. n-Alkanes lost by volatilization were mainly by the compounds of C10 to C17. Diesel in contaminated soil was mainly removed by biodegradation mechanism. First order degradation rate constant of TPH in sandy soil was ranged from 0.081 to 0.094/day, which is higher than that in silt loam(0.056-0.061/day). From fresh to 60day-aged soils, there was little difference of TPH biodegradation rate between the soils. Carbon recovery ranged from 0.61 to 0.89. TPH degradation rate was highly correlated with $CO_2$ production rate.

• Food Engineering Progress
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• v.22 no.4
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• pp.328-336
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• 2018

The aim of this study was to investigate the effect of pretreatments on quality of frozen peach. Pretreatments including steam blanching, water blanching, high pressure, and osmotic dehydration were applied to two varieties (Daeokgye and Hwangdo). Pretreated peaches were frozen and thawed at $-20^{\circ}C$ and $5^{\circ}C$, respectively. Steam blanching and osmotic dehydration with ascorbic acid reduced ${\Delta}E$ values without change of pH and acidity. Osmotic dehydration with sucrose decreased drip loss and increased brix. Freezing/thawing resulted in an increase of maximum force, while maximum force decreased with increasing time of steam and water blanching. Furthermore, osmotic dehydration with calcium chloride increased maximum force. High pressure decreased maximum force of Daeokgye and increased that of Hwangdo compared with non-treatment. Total polyphenol content, DPPH radical scavenging activity, and ABTS radical scavenging activity were improved by pretreatment including steam blanching, blanching, and osmotic dehydration with ascorbic acid.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.1
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• pp.127-134
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• 2018

This study evaluated the effects of high air temperature and waterlogging duration on growth and yield of Kimchi cabbage. Air temperature treatments were applied with ventilation; optimal (set $20^{\circ}C$) and delayed ($30^{\circ}C$) in the greenhouses. The waterlogging treatment levels were implicated 0, 12, 24, 48, and 72 hours, respectively. The growth of Kimchi cabbage was significantly affected by waterlogging duration. The head weight decreased by combining severe waterlogging and high air temperature. Net photosynthetic rate under the combination of non-waterlogging and optimal air temperature was $22.6{\mu}mol\;CO_2{\cdot}m^{-2}{\cdot}s^{-1}$, which was the greatest, while that of 72 hours-waterlogging was rapidly decreased. The percentage of formality with 0, 12, and 24 hours-waterlogging was over 88%, however, those of 72 hours-waterlogging with optimal and delayed ventilation were 64 and 68%, respectively, which were dramatically reduced. The yields were more affected by waterlogging duration than air temperature treatment because of deducting as increased waterlogging periods. These results indicate that waterlogging treatment reduced the yield and quality of Kimchi cabbage, thus it will be feasible to enhance the harvest time when severe waterlogging in the field.

• Journal of Bio-Environment Control
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• v.3 no.1
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• pp.58-65
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• 1994

It is necessary to effective temperature and humidity management for normal growth of crops in protected cultivation during the summer season. Because the highest temperature of vinyl house inhibit normal growth of crop and decrease of crop production or marketability in summer season. Finally, the vinyl house was impossible some crop cultivation in summer season. This study was conducted to investigate effective and economic method for temperature drop in protected cultivation during the summer season. 1. In medium size vinyl house(5$\times$13$\times$3m), the effect of temperature drop appeared the highest in treatment of shading with aluminium thermal curtain＋fog system＋ventilation with fan. The effect of temperature drop was about 1$0^{\circ}C$ lower than outer air temperature and about 4$^{\circ}C$ lower than outer soil temperature. 2. The effect of temperature drop according to shading with aluminium thermal curtain＋fog system＋ventilation with fan during the highest temperature of summer season Jul., 20 to Aug., 21 was appeared about 8$^{\circ}C$ lower than outdoor above ground(1.2m) and about 7$^{\circ}C$ lower than outdoor surface ground. 3. The changes of solar radiation during a day according to shading with aluminium thermal curtain＋ventilation with fan and shading with black curtain＋ventilation with fan treatments was appeared respectively about 29.3%, 32.5% of outdoor solar radiation a fine day and respectively about 27.4%, 31.8% of outdoor solar radiation a cloudy day.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.122-130
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• 2013

One of recent methods to protect wooden cultural assets from fire, there is the flame retardation which is applied directly to wood and it is to prevent fire through securing flame resistance for the material and delaying combustion when failed fire in advance and then to gain time for people in the room to evacuate and it has same goal with the Korean Fire Service Act by protecting life and property. However, in case of spraying flame retardant on the colored surface of the wooden cultural assets, there are continuous problems of decoloration, efflorescence and water absorbtion after sometime and accordingly there increases danger of damages of cultural assets. So when treating with flame retardant on wooden cultural assets, there has to be no problems on dancheong after sometime and securing sustainable methods for flmae retardation should be preceded. Accordingly, this study aims to provide basic sources for selecting proper flame retardation methods by evaluating and analyzing flame retardation capabilities according to types of flame retardants which are frequently used nowadays and spraying them on the dancheong-painted surface and confirming if there is no problem on the dancheong and wood after sometime and if flame retardation effect is sustainable with its quality and capability through precise analysis.

• Korean Journal of Plant Resources
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• v.21 no.4
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• pp.299-303
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• 2008

Two-year-old seedlings of Ilex rotunda were grown under control (full sunlight) and three different shading condition. Those conditions were full sunlight (PPFD 1600${\mu}mol\;m^{-2}\;s^{-1}$), 30% (PPFD 400${\mu}mol\;m^{-2}\;s^{-1}$), 50% (PPFD 250${\mu}mol\;m^{-2}\;s^{-1}$) and 70% treatment (PPFD 100${\mu}mol\;m^{-2}\;s^{-1}$). Total chlorophyll contents were inverse proportion to light intensity. Seedlings under full sunlight showed the highest photosynthetic activity such as photosynthetic rate, intercellular $CO_2$ concentration and water use efficiency. Photosynthetic activity trend was increased at the higher light intensity than the lower treatment over PPFD 500${\mu}mol\;m^{-2}\;s^{-1}$. Especially, seedlings under 70% treatment showed the worst photosynthetic activity at high light intensity. That result was regular for adapted plant in low intensity environment. Leaf area was also inverse proportion to light intensity, while dry weight per leaf area was shown the opposite trend.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.403-408
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• 2010

This study was carried out to investigate the physiological responses of $Rhododendron$ $mucronulatum$ Turcz. and $R.$ $indicum$ (L.) Sweet seedlings with 0%, 35%, 55% and 75% shading of full sunlight in polyethylene film house. The shading treatments were performed during the late growth season for each species (from Sept. 9 to Nov. 5, 2008). The shading treatment was effective in reducing the daily temperature by 0.9 to $1.7^{\circ}C$ during September and by 0.8 to $1.7^{\circ}C$ during October. Before the shading treatments, the water content of $R.$ $mucronulatum$ and $R.$ $indicum$ amounted to 68.5% and 66.3%, respectively. The water contents of two species after 75% shading treatment period decreased to 66.2% (3.4% reduction) and 65.9% (0.6% reduction), respectively. Notably, both species had a similar tendency indicating less reduction rate of water content with 75% shading. $R.$ $indicum$ showed higher photosynthetic capacity with higher level of shading, and its photosynthetic capacity reached the highest level ($9.63{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). On the other hand, shading-treated $R.$ $indicum$ showed higher intercellular $CO_2$ concentration, stomatal conductance and transpiration rate (55% shading > 35% shading > 75% shading) than non-treated ones. In addition, non-treated seedlings showed higher water use efficiency than treated ones. In particular, it was found that the leaf color of $R.$ $mucronulatum$ turned equivalent to purple under full sunlight, while its leaf color kept equivalent more to green with higher level of shading, as evidenced even in naked eyes. According to comprehensive analysis using Munsell Color Chart on potential leaf color variations of $R.$ $mucronulatum$ depending on the level of shading, it was found that relatively many leaf colors under full sunlight were equivalent to R (red) and Y (yellow) chart, while relatively many leaf colors with higher level of shading were equivalent to G (green) and Y chart, where the latter still showed green color.

• Journal of Animal Science and Technology
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• v.52 no.5
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• pp.427-434
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• 2010

This study was conducted to investigate the growth performance and meat quality improvement according to castration, optimal feeding management and ruminally protected amino acid-enriched fatty acid (RPAAFA) for the unselected Hanwoo bulls in the performance test. Bulls were castrated at approximately 14 months of age. Sixteen Hanwoo steers, 15 months of age and weighing $412.9{\pm}24.9kg$, were distributed into 2 groups. Steers were fed a basal diet supplemented with RPAAFA at 0 g (control) or 100 g (treatment), respectively for 12 months. Steers were slaughtered at 27 months of age. Average daily gain for treatment tended to be higher (p=0.10) than that of control, whereas feed conversion ratio tended to be lower (p=0.07) in treatment than in control. The supplementation of RPAAFA did not affect rib eye area, back fat thickness, meat color, fat color, texture and maturity. The appearance rates of yield 'A' grade and high quality grade ($1^{++}$, $1^+$ and 1) were higher in treatment than in control. The content of moisture, fat, protein and ash in longissimus muscles were similar between control and treatment. The supplementation of RPAAFA did not affect water-holding capacity, oxidation and reduction potential, myoglobin and fatty acid contents in longissimus muscles. Thus, present results indicate that castration, optimal feeding management and RPAAFA may be recommended for improving growth performance and quality grade of the unselected Hanwoo bulls in the performance test.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.304-313
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• 2019

Biopolymer based on microbial β-glucan and xanthan gum is effective for vegetation and has a function of enhancing soil strength, which can be used as soil reinforcement and stabilization materials in river embankment. The purpose of this study is to verify the vegetation effect of the surface of levee by biopolymer with seed spraying method. Mixed soils with biopolymer were used to cover the surface of embankments. The strength is higher in biopolymer-treated soil and xanthan gum based biopolymer has advantage for quality control in field scale. In addition, the vegetation of F. arundinacea and L. perenne showed various reactions with types of biopolymers. Biopolymer has a positive effect on the vegetation of them. In contrast, root growth tended to decrease in biopolymer-treated soils. The results indicate that root growth is slow down due to increasing ability to retain water in biopolymer-treated soil. In order to apply biopolymer to river embankment, it is necessary to examine the effects of biopolymers on a wide range of plant species in river embankment.