• Korean Journal of Mineralogy and Petrology
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• v.35 no.2
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• pp.101-109
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• 2022

The mobility and transport of radioactive cesium are crucial factors to consider for the safety assessment of high-level radioactive waste disposal sites in granite. The retardation of radionuclides in the fractured crystalline rock is mainly controlled by the hydrochemical condition of groundwater and surface reactions with minerals present in the fractures. This paper reports the experimental results of cesium sorption to the Wonju Granite, a typical Mesozoic granite in Korea, performed in an anaerobic chamber that mimics the anoxic environment of a deep disposal site. We measured the rates and amounts of cesium (¹³³Cs) removed by crushed granite samples in different electrolyte (NaCl, KCl, and CaCl₂) solutions and a synthetic groundwater solution, with variations in the initial cesium concentration (10^-5, 5×10^-6, 10^-6, 5×10^-7 M). The cesium sorption kinetic and isotherm data were successfully simulated by the pseudo-second-order kinetic model (r²= 0.99) and the Freundlich isotherm model (r²= 0.99), respectively. The sorption distribution coefficient of granite increased almost linearly with increasing biotite content in granite samples, indicating that biotite is an effective cesium scavenger. The cesium removal was minimal in KCl solution compared to that in NaCl or CaCl₂ solution, regardless of the ionic strength and initial cesium concentration that we examined, showing that K⁺ is the most competitive ion against cesium in sorption to granite. Because it is the main source mineral of K⁺ in fracture fluids, biotite may also hinder the sorption of cesium, which warrants further research.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.4
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• pp.273-279
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• 2021

This study was carried out to investigate the effects of a dietary addition of red ginseng marc, mineral^® and black sugar^® on the dry matter intake, daily gain, yield grade and quality grade of Holstein steers(Bos taurus). A total of 32 fattening Holstein steers(avg. BW 590kg) were assigned to four treatments which included a control diet(mixed concentrate and forage; namely, C) and three treatments diet(T1; control diet+red ginseng marc 200g, T2; control diet+red ginseng marc 100g+mineral 50g, T3; control diet+mineral 50g+ black sugar 20g). The results are summarized as follows; the total feed intake and daily feed intake were significantly(p<0.05) higher in T2 and T3 than in the other two treatments(C and T1). The daily gain was higher in T2 than in the other treatments, but there was no significant difference. The back fat thickness, longissimus muscle area and meat yield grade were no significant difference. The marbling score showed significantly(p<0.05) higher in order of T3(4.5) > T1(4.0) > T2(2.7) > C(2.5). The meat color, fat color, texture and maturity were no significant difference. The quality grade was higher in T3 than in the other treatments(C, T1 and T2), but there was no significant difference. T3, which numerically had a higher daily gain and carcass quality grade, showed higher economic efficiency, whereas C showed low economic efficiency. Based on the above results, T3 treatment compared to the other treatments improved the daily gain, carcass quality grade and economic efficiency.

• Korean Chemical Engineering Research
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• v.60 no.2
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• pp.243-248
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• 2022

As the scope of use of portable and wearable electronic devices is expanding, the limitations of heavy and bulky solid-state batteries are being revealed. Given that, it is urgent to develop a small energy harvesting device that can partially share the role of a battery and the utilization of energy sources that are thrown away in daily life is becoming more important. Contact electrification, which generates electricity based on the coupling of the triboelectric effect and electrical induction when the two material surfaces are in contact and separated, can effectively harvest the physical and mechanical energy sources existing in the surrounding environment without going through a complicated intermediate process. Recently, the interest in the harvest and utilization of wind energy is growing since the wind is an infinitely ecofriendly energy source among the various environmental energy sources that exist in human surroundings. In this study, the optimization of the energy harvesting device for the effective harvest of wind energy based on the contact electrification was analyzed and then, the utilization strategy to maximize the utilization of the generated electricity was investigated. Natural wind based Fluttering TENG (NF-TENG) using fluttering film was developed, and design optimization was conducted. Moreover, the safe high voltage generation system was developed and a plan for application in the field requiring high voltage was proposed by highlighting the unique characteristics of TENG that generates low current and high voltage. In this respect, the result of this study demonstrates that a portable energy harvesting device based on the contact electrification shows great potential as a strategy to harvest wind energy thrown away in daily life and use it widely in fields requiring high voltage.

• Journal of the Korean Applied Science and Technology
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• v.39 no.3
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• pp.397-406
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• 2022

This study is an experimental study on the single group pre-post test design for the effects of the exercise program combined with telephone coaching on postural balance, grip strength and depression of the elderly living alone. The subjects of this study were 20 elderly living alone who registered at a senior welfare center located in S City, Gyeonggi-do. A total of 12 session programs were applied from July 3 to October 14, 2021. Before and after the program, the participant's home was visited and 4 stage standing balance test(4 SBT), grip strength and depression were measured. The contents of the intervention consisted of elastic bands and grip balls, and weekly telephone coaching interventions were provided. In the result of this study, the exercise program combined with telephone coaching were statistically significant differences in 4 SBT(3stage)(t=-2.37, p=.029), 4 SBT(4stage)(t=-2.46, p=.024), right grip strength(t=-2.18. p=.042) and depression(t=2.82, p<.001). Therefore, it is expected that the exercise program combined with telephone coaching can be applied as a nursing intervention to improve postural balance, grip strength and reduce depression in the elderly living alone in the community.

• Korean Journal of Poultry Science
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• v.49 no.1
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• pp.1-8
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• 2022

We investigated the effects of stunning methods and gas treatments during slaughter on the quality characteristics of chicken breast and small intestine. Broilers (Ross 308) were stunned and slaughtered using halal, CO₂, or N₂ gas stunning methods (for 10 birds). After slaughter, the pH, proximate composition, color, water-holding capacity, cooking loss, and shear force of chicken breast muscle and small intestine were determined. Compared with the halal treatment, CO₂ treatment resulted in higher pH and lower cooking loss (P<0.05), and the pH, color, and shear force of chicken breast muscle with N₂ treatment were similar to those of the halal treatment (P>0.05). Compared with the halal treatment, the gas treatments resulted in lower pH and lightness and higher redness, yellowness, thickness, and shear force of the small intestine (P<0.05). However, compared with the CO₂ treatment, the N₂ treatment resulted in lower pH, redness, and yellowness, and higher lightness, thickness, and shear force. Overall, compared with the halal method, our results suggest that the use of N₂ gas suppresses the discoloration and deterioration of the texture of chicken meat and small intestine caused by CO₂ gas treatment in the gas stunning method.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.5
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• pp.379-386
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• 1990

Varietal difference of protein content in forty eight Korean recommended rice cultivars and environmental Variation in protein content of milled rice harvested at six sites of the middle and/or southern plain and four locations of mid-mountainous and/or alpine area in 1989 were investigated. Also, the composition of amino acid in milled rice was compared among three rice varieties: a high-protein japonica rice, Nongbaek, a high-protein Tongil-type rice, Yongjubyeo, and a low-protein japonica rice, Hwaseongbyeo. Korean recommended rice varieties showed 7.93% of average protein content with varietal variation from 5.5% to 10.2% for milled rice harvested in 1988, and 9.17% of mean protein content with the variation from 6.3% to 12.0% for milled rice harvested in 1989. Tongil-type rice was about 1% higher in protein content of milled rice than japonica. The low-protein japonica rice, Hwaseongbyeo exhibited lower content of essential amino acids per g of rice flour sample than the high-protein japoinica, Nongbaek and/or Tongil-type rice, Yongjubyeo, but the relative content of essential amino acids per 16.8g of nitrogen in milled rice of the former was not so different with those of the latters. Among amino acids the content of glutamic acid was highest and among essential amino acids the content of leucine was highest while methionine was lowest. The protein content of milled rice was negatively correlated with days from seeding to heading, K/Mg ratio, alkali digestion value(l-7) and amylose content, but it was positively correlated with translucency and magnesium content of milled rice. The protein content of milled rice harvested in the southern plain paddy field was about 1% higher compared with those harvested in the Middle plain. Also, the protein content of milled rice harvested in the southern mid-mountainous and alpine area was about 0.8% higher compared with those harvested in the resemble altitude area of the middle-northern part of Korea. The contribution of environmental variation to total in plain area was about 28.1% while that in mid-mountainous and alpine area was about 56.4%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.514-520
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• 1996

To clarify the proper nitrogen application level for rasing rice infant seedling under different nursery soil, Dongjinbyeo was raised at seedling box with different basal nitrogen level. The results are as follows. The higher the nitrogen level was, the lower emergence rate and the lower establishment rate. The establishment rate was less than 90%, when the nitrogen was more than 2g/box in hill soil and more than 1g/box in paddy soil. The more the nitrogen level was, the higher the seedling height in hill soil, but was higher in the order of N-2, 3, 1 and 0g /box. Leaf number wasn't significantly different between nusery soils and among nitrogen levels when seedling was raised more than 6 days. The endosperm survival rate was decreased as the increased nitrogen level, but wasn't different between the nursery soils. Amount of root was decreased as the increased nitrogen level in paddy soil, but was heavier in the order of N-1, 0, 2 and 3g /box in hill soil. Mat formation was better as the nitrogen level was decreased in all nursery soils. Considering the emergence rate, seedling charactors and mat formation, the proper nitrogen levels seemed to be 2g /box for hill soil and 1g /box for paddy soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.199-210
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• 2022

This study aimed to develop a cropping system to use limited crop-land with optimum efficiency, while considering management from farmers. To establish the cropping system involving a two-year rotation of three crops, three types of cropping system were evaluated in Suwon (Seogcheon series) and Anseong (Geumcheon series) in the middle plain area using six crops from 2018 to 2019: maize-perilla-onion, potato-sesame-garlic, and maize-sesame-onion. The crop productivity and income of the cropping systems involving food-, oilseed-, and horticultural crops were analyzed, and the optimal cropping system was reviewed. The total yield of each crop was as follows: maize 1,281 kg, potato 4,837 kg, perilla 125 kg, sesame 120 kg, onion 6,503 kg, and garlic 1,027 kg per 10a. However, in terms of gross profit, the potato was more than 3.8 times more profitable than corn, sesame was 1.8 times more profitable than perilla, and garlic was more than 2.8 times more profitable than onions. As a result, in terms of net income, the potato-sesame-garlic cropping system produced the highest income per unit area. Sesame seedlings were planted after the potato harvest, thereby solving the problem of competition between the first and last crops. Overall, this study confirmed that the potato-sesame-garlic cropping system, a two-year rotation of three crops, contributed to the improvement of upland crop productivity and farmers' income and was an overall effective cropping system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.4
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• pp.243-248
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• 2022

This study was conducted to evaluate the effect of feeding the whole crop rice silage (WCRS) which partially replaces the imported grass hay crop on the milking performance of Holstein and profitability. Two experimental diets were used according to the traditional practice of dairy farms. The control diet (C) was composed of 13kg/day of mixed hay, 6.8kg/day concentrate, and orchardgrass/bermudagrass hay (1.8kg/day). The treatment diet (T) was composed of 9.6kg/day of mixed hay, 6.8kg/day of concentrate and 2.2kg/day of WCRS. The CP content of the WCRS (4.6%) was lower than orchardgrass (11.3%) and bermudagrass hay (8.4%) due to the harvest being 30days later than the optimum harvest date of rice. The lower intake was observed in T during the entire experiment period which seems to be related to the higher proportion of fiber in rice (p<0.05). No significant difference was found in milk production between C (26.9kg) and T (26.3kg) during the entire experiment period (p>0.05). Also, no difference in milk fat, milk protein, total solids, and milk composition was observed between the two diets. Higher income per head was resulted in T (21,141won) compared to C (21,915 won). These results indicate that the partial replacement of the grass hay by the WCRS can bring the profit to the dairy farm due to the no difference between the control diet and the treatment diet.

• Journal of the Korean Applied Science and Technology
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• v.40 no.1
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• pp.13-23
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• 2023

This study is an experimental study on the single group pre-post test design for the effects of the aroma inhalation method with roll-on on stress, pain, depression and blood pressure of the elderly. 33 elderly people who met the selection criteria participated among the elderly using the senior citizen clubs located in S city, Gyeonggi-do. The data collection period was from November 14, 2022 to December 19, 2022. A questionnaire consisting of stress, pain, depression, and blood pressure was measured before and after the aroma roll-on inhalation intervention. The components of aroma essential oil included Marjoram, Geranium, Peppermint and Orange sweet that were diluted in Jojoba oil which was the carrier oil. The aroma inhalation method with roll-on was carried out 3 times day for 4 weeks. In the result of this study, the aroma inhalation method with roll-on were statistically significant differences in stress(t=2.63, p=.013), pain(t=2.46, p=.019), and systolic blood pressure(t=3.01, p=.005) of the participants. Therefore, aroma roll-on therapy is expected to be available as a useful nursing intervention method for reducing stress, relieving pain, and managing blood pressure in the elderly using the senior citizen clubs.