• Korean Journal of Materials Research
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• v.21 no.4
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• pp.232-235
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• 2011

ZnO nanorods for gas sensors were prepared by a hydrothermal method. The ZnO gas sensors were fabricated on alumina substrates by a screen printing method. The gas-sensing properties of the ZnO nanorods were investigated for $CH_4$ gas. The effects of growth time on the structural and morphological properties of the ZnO nanorods were investigated by X-ray diffraction and scanning electron microscope. The XRD patterns of the nanocrystallized ZnO nanorods showed a wurtzite structure with the (002) predominant orientation. The diameter and length of the ZnO nanorods increased in proportion to the growth time. The sensitivity of the ZnO sensors to 5 ppm $CH_4$ gas was investigated for various growth times. The ZnO sensors exhibited good sensitivity and rapid response-recovery characteristics to $CH_4$ gas, and both traits were dependent on the growth time. The highest sensitivity of the ZnO sensors to $CH_4$ gas was observed with the growth time of 7 h. The response and recovery times were 13 s and 6 s, respectively.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.spc
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• pp.54-60
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• 2023

The government focuses on promoting start-ups, fostering ventures, and creating an ecosystem of start-ups through the formation of a strong growth environment for small businesses. This study provides academic and practical implications about ways of improving our business incubator's support service across stages of growth through IPA. To this end, an Importance-Performance Analysis (IPA) was conducted to analyze relationship and differences in importance and satisfaction of business incubator's support service support at business incubation center. These results present to provide the following academic and practical implications. The academic implications are the need for differences in support services for each phase of start-up growth. As factors that could increase the likelihood of successful start-up were identified in each phase of the start-up growth, important information needed for policy and strategy was provided. As a practical suggestion, the managers and expert groups are presented with sections to be opened for each start-up growth stage, minimum effort input, and areas to be maintained continuously. A systematic support plan is established and a foundation is provided for improvement measures in efficient start-up business incubator's support service.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.2
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• pp.230-235
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• 2020

Objective: This study was realized to evaluate the nutritional value of rice grains as a replacement for corn grains in the diet of growing Hanwoo steers. Methods: Two experimental diets were prepared: i) Corn total mixed ration (TMR) consisting of 20% corn grains and ii) Rice TMR consisting of 20% rice grains, in a dry matter (DM) basis. These treatments were used for in vitro rumen fermentation and in vivo growth trials. In the rumen fermentation experiment, the in vitro DM digestibility (IVDMD), in vitro crude protein digestibility (IVCPD), in vitro neutral detergent fiber digestibility, pH, ammonia nitrogen, and volatile fatty acids (VFA) were estimated at 48 h, and the gas production was measured at 3, 6, 12, 24, and 48 h. Twenty four growing Hanwoo steers (9 months old; body weight [BW]: 259±13 kg) were randomly divided into two treatment groups and the BW, dry matter intake (DMI), average daily gain (ADG), and feed conversion ratio (FCR) were measured. Results: The in vitro experiment showed that the IVDMD, IVCPD, and VFA production of the Rice TMR were higher than those of the Corn TMR (p<0.05). The growth trial showed no differences (p>0.05) in the final BW, ADG, DMI, and FCR between the two TMRs. Conclusion: The use of rice grains instead of corn grains did not exhibit any negative effects on the rumen fermentation or growth performance, thereby rice grains with a DM of less than 20% could be used as a starch source in the diet of growing steers.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.310-317
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• 2022

BACKGROUND: The salt in soil interrupts crop growth. Therefore, water resources are used to remove any salt found in the soil. However, water resources have been reduced by global warming; thus, a new study is required into reducing the salt in soil. Recently, the bottom ash (BA) of a biomass power plant was found to be similar to biochar. Hence, it can be used to remove heavy metals and wastewater through the adsorption characteristics of BA. The objective of this study was to evaluate the improvement effects on crop growth in saline soil containing the BA from biomass power plants. METHODS AND RESULTS: The effect on crop growth in the saline soil supplemented with BA was studied with the crop-planted pots, which were packed by reclaimed greenhouse soils collected from Byolyang, Suncheon. The BA application level was 25, 50, 100, 200, and 400 kg/10a (referred as BA25, BA50, BA100, BA200, and BA400, respectively). The BA increased the fresh weights of the leaf and root, while nitrogen uptake increased by approximately 24-102% and 54-77%, respectively for the lead and root. The phosphorous uptake increased by 38%, although only in the leaf of the lettuce. In the case of soil, BA increased water content, pH, EC, CEC, and NH₄⁺ and the SAR of the soil decreased by 5-15%. The bottom ash increased the contents of Ca²⁺ and Mg²⁺, and fixed the amount of Na⁺. CONCLUSION(S): It was confirmed the bottom ash of a biomass power plant, based on wood pellets, improved crop growth, and increased the nutrient uptake of crops in saline soil. In addition, bottom ash, which has a wide range of porosity and high values of pH and EC, improved properties of the saline soil. However, the BA has a large amount of B, As, and heavy metals. Finally, it may require a study on the safety and contamination of heavy metals contained in the bottom ash, which would be applied in soil for a long time.

• Bulletin of the Korean Mathematical Society
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• v.61 no.4
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• pp.917-932
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• 2024

In this paper, we deal with the Euler-Maruyama (EM) scheme for stochastic differential equations driven by G-Brownian motion (G-SDEs). Under the linear growth and the local Lipschitz conditions, the strong convergence as well as the rate of convergence of the EM numerical solution to the exact solution for G-SDEs are established.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.15-25
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• 2019

Contamination of soil by deicing salt is among the important environment problems due to their toxicity and negative impact to human health and the environment. One of the effective methods for cleaning the soil from deicing salts is desalination using soil amendment-phytoremediation continuum treatment. The purpose of this study was to determine how much of the pH, EC control and Ca²⁺, Na⁺, Mg²⁺, and K⁺ taken up soil amendments and Miscanthus sinensis, and to evaluate the effect of salt reduction and growth improvement as affected by soil amendment in high concentration of calcium chloride (CaCl₂) deicing salts. Results indicated that the addition of soil amendments was decrease the EC and pH, also significantly reduce the leaching of Ca²⁺, Na⁺, Mg²⁺, K⁺, a chloride ions related deicing salts, compared to the control for CaCl₂ 10 g/L treatment. It also resulted in an enhanced plant growth and higher plant height, leaf length, leaf width, number of leaves, fresh weight and dry weight in Hydroball treatment + Miscanthus sinensis planting continuum treatment compared to the treatment that planted Miscanthus sinensis only. Therefore, we concluded that soil amendments might be attributed to an accumulation of deicing slats in the roadside soil, resulting in the improvement of Miscanthus sinensis growth.

• Journal of the Korea Society of Computer and Information
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• v.15 no.11
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• pp.83-90
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• 2010

In this paper, we developed the program related green growth based Educational-Robot in the framework of Convergence for the community child welfare centers' children who are in poverty and broken homes as the way to enhance the competitiveness about education and a solution to cope with actively about the main tasks of the state for human resources in the future. Through the program developed, it has been verified the impact on the energy saving attitude. According to this result, it has been proved that convergence study program linked green growth for children of community welfare child center is effective to energy saving attitude. Through it, it is expected to help to meet the educational needs of the community child welfare centers' children.

• Journal of Environmental Science International
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• v.31 no.3
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• pp.247-254
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• 2022

This study investigated the effect of vegetation mat on plant growth and salt reduction in the soil treated with high concentration deicing salt. In order to measure soil chemical characteristics and plant growth, three native groundcover plants (Dendranthema zawadskii var. latilobum, Dendranthema boreale, and Kalimeris yomena) were grown in each of the three plastic containers (50.0 cm width × 35.0 cm length × 8.5 cm deep) with a high concentration treatment of calcium chloride deicing salt. There were two treatments: control, and BVM that combines B (blanket) and VM (vegetation mat). 1,600 g of soil was placed on the top of the drainage layer with 290 g of perlite, 100 seeds each of the three native plants with three repetitions were sowed, and 10 g/L of calcium chloride deicing salt was added in the treatment. As a result of the chemical properties of soil, soil in control treatment was acidic and soil electrical conductivity in BVM was the lowest. Also, exchangeable cations (K⁺, Ca²⁺, Na⁺, and Mg²⁺) in soil and all the three plants were significantly decreased in the BVM treatment. Meanwhile, the germination rate of Dendranthema zawadskii var. latilobum was the highest under high concentration deicing salt in compared to the two plants. Overall, three native groundcover plant growth was higher in the BVM than control treatment significantly. These results suggest that the treatment of blanket vegetation mat has a positive effect on soil and plant growth in soil damaged by deicing salt.

• ETRI Journal
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• v.28 no.6
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• pp.787-789
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• 2006

In this letter, we report that vertically well-aligned ZnO nanowires were grown on GaN epilayers and c-plane sapphire via a vapor-liquid-solid process by introducing a 3 nm Au thin film as a catalyst. In our experiments, epitaxially grown ZnO nanowires on Au-coated GaN were vertically well-aligned, while nanowires normally tilted from the surface when grown on Au-coated c-$Al_2O_3$ substrates. However, pre-growth annealing of the Au thin layer on c-$Al_2O_3$ resulted in the growth of well-aligned nanowires in a normal surface direction. High-resolution transmission electron microscopy measurements showed that the grown nanowires have a hexagonal c-axis orientation with a single-crystalline structure.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.495-500
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• 2015

Currently the fish aquaculture industry of Korea is focused on the mass culture of flatfish (Paralichthys olivaceus) and and rockfish (Sebastes schlegeli) with completely controlled culture techniques. Recently, there has been considerable interest in new species development, such as the starry flounder (Platichthys stellatus). The value of starry flounder (Platichthys stellatus) as a raw fish increases with time because it is tasty, light, and bouncy. In this paper, the growth characteristics dependent on the LED wavelengths and the optimal growth conditions of the starry flounder were studied. In these experiments 4 different kinds of LED lighting, configurations were designed and prepared using red, green, blue and white, respectively. The fish aquaculture experiments were conducted over 10 weeks in four fish tanks, each installed with a different color of LED lighting. 10 starry flounders of 13 ~ 17g were placed into each tank. The effects of each color of light on the growth rate of the starry flounders were then examined. As a result, the starry flounders under the green LED lighting showed the highest growth rate, followed by the white, red, and blue LED lighting. Based on these results, a green light provides a suitable breeding environment for the starry flounder.