• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.3
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• pp.411-417
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• 2023

During the operation of a nuclear power plant (NPP), the generation of radioactive waste, including dry active waste (DAW), concentrates, spent resin, and filters, mandates the implementation of appropriate disposal methods to adhere to Korea's waste acceptance criteria (WAC). In this context, this study investigates the potential use of polymer concrete (PC) as a high-integrity container (HIC) material for solidifying and packaging these waste materials. PC is a versatile composite material comprising binding polymers, aggregates, and additives, known for its exceptional strength and chemical stability. A comprehensive analysis of PC's long-term integrity was conducted in this study. First, its compressive strength, which is crucial for ensuring the structural stability of HICs over extended periods, was evaluated. Subsequently, the resilience of PC was tested under various stress conditions, including biological, radiological, thermal, and chemical stressors. The findings of this study indicate that PC exhibits remarkable long-term properties, demonstrating exceptional stability even when subjected to diverse stressors. The results therefore underscore the potential viability of PC as a reliable material for constructing high-integrity containers, thus contributing to the safe and sustainable management of radioactive waste in NPPs.

• Journal of Wellbeing Management and Applied Psychology
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• v.7 no.4
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• pp.15-20
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• 2024

Purpose: Climate change is greatly affecting the frequency and intensity of fires around the world. The main effects of climate change on fires are rising temperatures, dry seasons and extreme droughts, changes in precipitation, increased strong winds, extended fire danger periods, and changes in natural ecosystems. Several factors due to climate change are increasing the risk of large-scale fires, such as wildfires. Research design, data and methodology: Rising temperatures caused by climate change will make forests and grasslands drier, make it easier for wildfires to occur in drier environments and spread quickly to wider areas, and the generated wildfires will release large amounts of greenhouse gases into the atmosphere, such as carbon dioxide (CO₂), and the released greenhouse gases will strengthen the global greenhouse effect, further raising the temperature. As temperatures rise, the risk of wildfires increases in drier environments, and this process is repeated, leading to a vicious cycle of intensifying climate change as more fires occur and more greenhouse gases are released. Results: In conclusion, climate change is increasing the risk of fire occurrence and this phenomenon is expected to become more frequent and severe in the future. Conclusions: In order to cope with the increasing fire risk caused by climate change, fire prevention and management. Fire detection and response systems need to be strengthened, supportive policies and international cooperation are needed to restore ecosystems, and these measures, along with fire prevention, management and countermeasures, should take into account long-term climate change and adaptation as well as short-term responses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.69-89
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• 1981

Stevia (Stevia rebaudiana Bertoni) is a perennial herb widely distributed in the mountainous area of Paraguay. It belongs to the family Compositae and contains 6 to 12 percent stevioside in the leaves. Stevioside is a glucoside having similar sweetening character to surgar and the degree of sweetness is approximately 300 times of sugar. Since Korea does not produce any sugar crops, and the synthetic sweetenings are potentially hazardous for health, it is rather urgent to develop an economical new sweetener. Consequently, the current experiments are conducted to establish cultural practices of stevia, a new sweetening herbs, introduced into Korea in 1973 and the results are summarized as followings: 1. Days from transplanting of cuttings to the flower bud formation of 6 stevia lines were similar among daylengths of 8, 10 and 12 hours, but it was much greater at daylengths of 14 or 24 hour and varietal differences were noticable. All lines were photosensitive, but a line, 77013, was the most sensitive and 77067 and Suweon 2 were less sensitive to daylength. 2. Critical daylength of all lines seemed to be approximately 12 hours. Growth of plants was severely retarded at daylengths less than 12 hours. 3. Cutting were responded to short daylength before rooting. Number of days from transplanting to flower bud formation of 40-day old cuttings in the nursery bed was 20 days and it was delayed as duration of nursery were shorter. 4. Number of days from emergence to flower bud formation was shortest at short day treatment from 20 days after emergence. It was became longer as initiation of short day treatment was earlier or later than 20 days. 5. Plant height, number of branches, and top dry weight of stevia were reduced as cutting date was delayed from March 20 to May 20. The highest yield of dry leaf was obtained at nursery duration of 40-50 days in march 20 cutting, 30-40 days in April 20 cutting, and 30 days in May 20 cutting. 6. An asymptotic relationship was observed between plant population and leaf dry weight. Yield of dry leaf increased rapidly as plant population increased from 5,000 to 10,000 plants/10a with a reduced increasing rate from 10,000 to 20,000 plants/l0a, and levelled off at the plant population higher than 20,000 plants/l0a. 7. Stevia was adaptable in Suweon, Chengju, Mokpo and Jeju and drought was one of the main factors reducing yield of dry leaf. Yield of dry leaf was reduced significantly (approximately 30%) at June 20 transplanting compared to optimum transplanting. 8. Yield of dry leaf was higher in a vinyl house compared to unprotected control at long daylength or natural daylength except at short day treatment at March 20. Higher temperature ill a vinyl house does not have benefital effects at April 20 transplanting. 9. The highest content of stevioside was noted at the upper leaves of the plant but the lowest was measured at the plant parts of 20cm above ground. Leaf dry weight and stevioside yield was mainly contributed by the plant parts of 60 to 120cm above ground but the varietal differences were also significant. 10. Delayed harvest by the time of flower bud formation increased leaf dry weight remarkably. However, there were insignificant changes of yield as harvests were made at any time after flower bud formation. Content of stevioside was highest at the time of flower bud formation and earlier or later harvest than this time was low in its content. The optimum harvesting time determined by leaf dry weight and stevioside content was the periods from flower bud formation to right before flowering that would be the period from September 10 to September 15 in Suweon area. 11. Stevioside and rebaudioside content in the leaves of Stevia varieties were ranged from 5.4% to 14.3% and 1.5% to 8.3% respectively. However, no definit relationships between stevioside and rebaudioside were observed in these particular experiments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.939-944
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• 2002

We have screened the microorganisms from pigs feces for the development of probiotics which have acid-and bile-tolerance. Among them, a strain which was identified as Enterococcu durans LP44 was selected. Sixty Duroc$\times$Yorkshire$\times$Landrace pigs (6.30$\pm$0.04 kg average initial body weight) were used in a 14 days growth assay to determine the effects of Enterococco duran Lf44 culture on growth performance of weaned pigs. Dietary treatments included 1) DF (dry feeding),2) W (wet feeding),3) WF+5ED (wet feeding+5% Enterocucu duran LP44 culture),4) WF+ 10ED (wet feeding +10% Enterococcus durans LP44 culture). For overall periods, average daily gain in pigs fed % diet tended to increase compared to pigs fed DF diet without significant difference. Also, there was no significant difference in gain/feed. At 5 days after the onset of the experiment, pigs fed WF+5ED and WF+10ED diets were significantly increased in dry matter and nitrogen digestibilities compared to pigs fed DF and W diets (p<0.05). At 14 days after the onset of the experiment, pigs fed WF+ 10ED diet were significantly increased in dry matter digestibility compared to pigs fed DF diet (p<0.05). Also, pigs fed WF + 10ED diet were significantly increased in nitrogen digestibility compared to other treatments (p<0.05). In conclusion, supplemental Enterococcus durans LP44 was an effective means of improving ADG and nutrient digestibility.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1253-1253
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• 2001

The ability to accurately assess wine quality is important during the wine making process, particularly when allocating batches of wines to styles determined by consumer requirements. Grape payments are often determined by the quality category of the wine that is produced from them. Wine quality, in terms of sensory characteristics, is normally a subjective measure, performed by experienced winemakers, wine competition judges or winetasting panellists. By nature, such assessments can be biased by individual preferences and may be subject to day-to-day variation. Taste and aroma compounds are often present in concentrations below the detection limit of near infrared (NIR) spectroscopy but the more abundant organic compounds offer potential for objective quality grading by this technique. Samples were drawn from one of Australia's major wine shows and from BRL Hardy's post-vintage wine quality allocation tastings. The samples were scanned in transmission mode with a FOSS NIR Systems 6500, over the wavelength range 400-2500 ㎚. Data analysis was performed with the Vision chemometrics package. With samples from the allocation tastings, the best correlations between NIR spectra and tasting data were obtained with dry red wines. These calibrations used loadings in the wavelengths related to anthocyanins, ethanol and possibly tannins. Anthocyanins are a group of compounds responsible for colour in red wines - restricting the wavelengths to those relating to anthocyanins produced calibrations of similar accuracy to those using the full wavelength range. This was particularly marked with Merlot, a variety that tends to have relatively lower anthocyanin levels than Cabernet Sauvignon and Shiraz. For dry white wines, calibrations appeared to be more dependent on ethanol characteristics of the spectrum, implying that quality correlated with fruit maturity. The correlations between NIR spectra and sensory data obtained using the wine show samples were less significant in general. This may be related to the fact that within most classes in the show, the samples may span vintages, glowing areas and winemaking styles, even though they may be made from only one grape variety. For dry red wines, the best calibrations were obtained with a class of Pinot Noir - a variety that tends to be produced in limited areas in Australia and would represent the least matrix variation. Good correlations were obtained with a tawny port class - these wines are sweet, fortified wines, that are aged for long periods in wooden barrels. During the ageing process Maillard browning compounds are formed and the water is lost through the barrels in preference to ethanol, producing “concentrated” darkly coloured wines with high alcohol content. These calibrations indicated heaviest loadings in the water regions of the spectrum, suggesting that “concentration” of the wines was important, whilst the visible and alcohol regions of the spectrum also featured as important factors. NIR calibrations based on sensory scores will always be difficult to obtain due to variation between individual winetasters. Nevertheless, these results warrant further investigation and may provide valuable Insight into the main parameters affecting wine quality.

• Korean Journal of Organic Agriculture
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• v.14 no.2
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• pp.191-204
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• 2006

This study was conducted to identify the effect of planting date and cultivation method on soybean growth and yield in paddy field. The plant height of soybeans in single cropping(SC) was higher than those in cultivating after barley culture (CB). Considering planting date and cultivation method, plant height tend to be higher in SC with level row cultivation(LR) and in CB with high ridge cultivation(HR). In this SC method, nodule formation in LR was better than in HR, but number of nodules of cv. Hwangkeumkong was highest, regardless of planting date and cultivation method. In the progress of growth stage, leaf areas of all cultivars were distinctively increased in CB than in SC. However, dry weight of top plants and roots in SC was comparably higher than that in CB due to growing periods of the soybeans. In cultivation methods, general type of dry weight of top plants was higher in LR than in HR, however, root dry weight was via verses. Growth responses varied depending on cultivars, cultivation methods, and planting date and these factors affected to shoot root (T/R) ratio. The T/R ratios in LR and SC were higher than those in HR and CB. In R8 stage, number of pods and ripened seed varied depending on cultivars. cv. Hwaeomputkong, which showed early maturing trait, was lowest. However, both yield factors tended to be higher in HR and CB than in LR and SC. The ratios of ripened seeds percentage of cv. Hwangkeumkong and cv. Eunhakong were higher in CB than in SC. However, yields of cv. Daewonkon and cv. Taekwangkong were higher in CB than in SC.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.3
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• pp.373-377
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• 2007

Alfalfa silage and corn silage are the major dairy feeds in most dairy operations in Michigan, USA. In recent years, the need to improve digestible fiber and dry matter intake of forages to meet the nutrient requirements of high yielding dairy cows and the willingness to plant corn specifically for silage has led plant breeders to focus on the brown mid-rib (BMR) trait. The objective of this study was to investigate the effect of different ratio of alfalfa to BMR corn silage and ration level of forage neutral detergent fiber (NDF) on animal performance of lactating cows in the Upper Peninsula of Michigan. This study was conducted at the Upper Peninsula Experiment Station of Michigan State University in Chatham, Michigan, USA. Two different ratios of forage type (high alfalfa silage/low BMR corn silage, AS, and high BMR corn silage/low alfalfa silage, BMRCS) and two different dietary NDF contents (27% NDF, 27 = low forage/high grain feeding, and 33% NDF, 33 = high forage/low grain feeding) were used. The experimental design was a $4{\times}4$ Latin Square with 20 milking cows (12 multiparous and 8 primiparous). This trial had four 21-day periods with 14 d adaptation and 7 d data collection. Milk yield and body condition score (BCS) on the AS-27, BMRCS-27 and BMRCS-33 treatments were significantly (p<0.05) higher than on the AS-33 treatment. Dry matter intake of the AS-27 and BMRCS-27 treatments was significantly (p<0.05) higher than for the AS-33 and BMRCS-33 treatments. Milk urea nitrogen (MUN) on the AS-33 treatment was significantly (p<0.05) higher than on the other diet treatments. A key finding of this study was that the BMRCS-33 (higher amounts of brown mid-rib corn silage than alfalfa silage, high forage and low grain feeding diet at 33% NDF) led to the equal highest milk production whilst having the equal lowest dry matter intake. This study demonstrated that the diet with higher ratio of highly digestible NDF forage such as brown mid-rib corn silage to alfalfa silage could lower grain feeding in the ration.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.4
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• pp.283-289
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• 2015

Three experiments were carried out to determine the effect of harvest maturity and management practices on the dry matter losses and morphological changes of round baled rye silage. Rye was harvested at three growing stages (boot, heading and flowering stage) in three different conditions i) with wilting (unwilted, short wilting and long wilting), ii) with inoculant treatment (untreated, inoculant A and inoculant B) and iii) with three different wrap colors (white, black and green). The morphological changes in round bale silage after 2 months was heavy in the early harvest and unwilted silage. However, harvesting after the heading stage did not change the shape, significantly. Inoculant treatment reduced the morphological changes and dry matter (DM) losses of round baled rye silage. DM loss was decreased with a delayed harvesting date and was significantly reduced by the inoculant. Dramatic changes in the shape were observed in all treatment at boot stage. Inoculant treatment resulted in more severe changes in the boot stage compared to untreated silage. Black color wrapping had the greatest impact among the wrap colors and there were no significant difference in the wrap colors. Harvest maturity and wilting periods was highly correlated (p<0.01) with morphological change. Result of these studies indicated that dry matter content is the most important factor that affects the morphological change in round bale silage.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.205-216
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• 2002

This study was conducted to examine the effect of long-day (LD) period before short-day (SD) treatment on the vegetative growth of greenhouse-grown cut chrysanthemum cv. Reagan Improved at Wageningen Agricultural University, The Netherlands. Rooted cuttings of cut chrysanthemum cv, Reagan Improved were transplanted on 6th, 13th, 20th of September and all of them were treated with LD before SD treatment on 27th of September, The periods from transplanting until final harvest were 70, 77, and 84 days for 1, 2, and 3 week-LD treatment, respectively. The final plant height increased in the plot of 3 week-LD period and decreased in the plot of 1 week-LD period before the SD treatment. Total fresh weight and the leaf area were increased more in the plot of 3 week-LD period than that of 1 week-LD period, but the absolute growth rate after SD treatment was the same on plant growth rate and increase of the number of leaves in all treatments. The final dry matter production (g.m$^{-2}$ ) was increased more in the plot of 3 week-LD period than that of 1, 2week-LD period before SD treatment. Plant height and fresh weight were followed by the condition of LD period. In addition, dry mass production was highest in 3 week-LD period.

• Journal of Life Science
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• v.19 no.8
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• pp.1088-1092
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• 2009

This study was conducted to determine an estimated value and change in TDF (total dietary fiber) binding major minerals (Ca, P, K Mg) of soybean sprouts depending on cultivation periods of 1, 3 or 5 days, and parts of cotyledon and hypocotyl. The compositions of TDF binding major minerals in soybean sprouts were evaluated by the enzymatic-gravimetric method developed by Prosky and adopted by AOAC. The content of TDF binding P ranged between 915.28 mg and 1037.82 mg per 100 g cotyledon. Average contents of Ca, K, and Mg in cotyledon ranged between 541.67 mg and 634.34 mg, 180.91 mg and 253.98 mg, 231.90 mg and 301.01 mg, respectively, on dry matter basis. The average contents of TDF binding Ca in hypocotyl per 100 g were between 454.36 mg and 540.33 mg, and other major minerals contents were between 149.24 mg and 186.21 mg for P, 164.17 mg and 182.78 mg for K, and 152.53 mg and 161.22 mg for Mg, respectively. The proportional changes of Ca, an estimated value in cotyledon, ranged between 5.58% and 30.98%, 47.18% and 59.10% for P, 95.24% and 95.50% for K, and 58.45% and 68.64% for Mg, respectively, based on dry matter. An estimated value of Ca, P, K, and Mg in hypocotyl ranged between 6.71% and 13.52%, 91.03% and 91.76%, 96.91% and 98.92%, and 61.03% and 66.37%, respectively, on dry matter basis.