• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.303-310
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• 2018

Purpose: This research was conducted to determine the design factors of a seed-metering device for the development of a seeder. The device allows the seeder to sow precisely one to three seeds of foxtail millet and sorghum. To obtain fundamental information regarding the design of the seed-metering device, examination of the physical properties of foxtail millet and sorghum was conducted. Methods: Based on the results of an adaptability test using an existing seeder with foxtail millet and sorghum, an experimental roller-type seed-metering device was made. The seeding factors considered during the experiment were the width, length, and depth, as well as the shape of the groove in the seed-metering roller. By adapting an analysis of variance, the experimental results of the seeding factors were analyzed. Results: The measured results of the respective lengths and widths of the seeds were 2.11 and 1.64 mm for foxtail millet, and 3.68 and 3.32 mm for sorghum, respectively. The weight of 1,000 seeds was 2.43 g for foxtail millet and 17.5 g for sorghum. The seeds were of an elliptical shape, considering the length and width. A sieve analysis showed that the size distribution of foxtail millet was quite regular whereas that of sorghum was irregular. Conclusions: The seeding results showed that the rates of incorrect planting were low when the groove of the roller-type metering device is an elliptical type. To sow one to three seeds, the groove of roller-type metering devices $2.0mm{\times}4.0mm{\times}1.5mm$ ($width{\times}length{\times}depth$) for foxtail millet, and $4.0mm{\times}8.0mm{\times}3.0mm$ and $4.5mm{\times}8.0mm{\times}3.0mm$ ($width{\times}length{\times}depth$) for Sorghum.

• Journal of Climate Change Research
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• v.4 no.2
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• pp.141-158
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• 2013

In this study, the projection of future heating and cooling degree days (HDDs and CDDs) has been conducted over South Korea for the period 1996~2005 with 2046~2055 and 2091~2100, using CCSM3 and MM5 simulations driven by the six IPCC SRES emission scenarios (A2, A1B, A1FI, A1T, B1, and B2). Annual mean surface air temperature increases by $1.2{\sim}3.4^{\circ}C$ at the end of the 21st century comparing to the present-day (1996~2005) in South Korea. HDDs decrease by 8~25% and CDDs increase up to 242~1,448% with corresponding changes in temperature. These increases and decreases also change the duration of HDDs and CDDs. HDDs duration decreases by 1 month, while the expansion of CDDs duration is much longer than 2 months. Thus, projected future HDDs and CDDs changes appear that cooling energy demand in summer season would increase and heating energy demand in winter would decrease in the future. Especially, these remarkable changes would be obvious at high mountain area, Gangwon-do and at south area, Jeju island. In the sense of future energy supply and policy, electrical energy for cooling in summer could be getting much more its importance rather than fossil energy used for heating in winter.

• Korean Journal of Food Science and Technology
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• v.51 no.2
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• pp.103-108
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• 2019

This study was conducted to select the optimal extraction method of codonopsis lanceolata saponin. To investigate the lancemasides content depending on each extraction method, various extractions were performed: reflux (methanol and butanol), hot water, as well as ultrasonic bath (40 kHz; continuous irradiation/interval irradiation) and ultrasonicator (20 kHz) extractions. From the result, the overall lancemasides content were the highest in ultrasonic bath (MeOH; continuous irradiation) extraction, followed by ultrasonic bath (water; continuous irradiation)>ultrasonic bath (MeOH; interval irradiation)>ultrasonicator (MeOH)>hot water>MeOH reflux>BuOH reflux extractions in that order. Sample drying method prior to ultrasonic bath extraction was more effective shade drying than freeze drying. Effective duration and temperature of extraction was 2 hr at $64^{\circ}C$. And ingredient change diverted from aster saponin Hb to lancemasides was identified by extraction condition such as extraction time and temperature.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.135-143
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• 2021

Aerospace and geospatial technologies have become more accessible by researchers and agricultural practitioners, and these technologies can play a pivotal role in transforming current pest management practices in agriculture and forestry. During the past 20 years, technologies including satellites, manned and unmanned aircraft, spectral sensors, information systems, and autonomous field equipment, have been used to detect pests and apply control measures site-specifically. Despite the availability of aerospace and geospatial technologies, along with big-data-driven artificial intelligence, applications of such technologies to apple IPM have not been realized yet. Using a case study conducted at the Korea Apple Research Institute, this article discusses the advances and limitations of current aerospace and geospatial technologies that can be used for improving apple IPM.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.455-460
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• 2020

Rice grain damage caused by Paromius exiguus under various conditions in paddy fields was analyzed. One nymph of P. exiguus caused 2.7 pecky grains in brown rice in one day, and sixteen nymphs caused 132.3 pecky grains over sixteen days. The relationship between the inoculated nymphal density and the number of pecky grains was well described by a linear regression (Y = 8.8446X, r2 = 0.9622). When a pair of P. exiguus adults was inoculated in the heading stage of rice, the damage at the time of harvesting consisted of 40.2% of cracked rice and 30.5% of pecky rice among whole rice grains. Inoculation of 16 pairs resulted in 81.7% of cracked rice and 74.5% of pecky rice. The damage analysis indicated that the quantity of ripened rice decreased as the damage started earlier in the heading stage of rice. On the contrary, the proportion of cracked and pecky rice rapidly increased from the heading time until 28 days after heading of the rice grains.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.495-505
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• 2022

The purpose of this study was to examine the influence of altruism and social trust on giving behavior for COVID-19 among citizens and the differences by gender and age. To this end, this study conducted analyses with a sample of 2,006 regular citizens from the Giving Korea 2020 survey constructed by the Beautiful Foundation. The main analysed results are as follows. First, citizens' altruism and social trust significantly positively influenced giving behavior for COVID-19. Specifically, when altruism increased by one level, the likelihood of giving participation increased about 3.00 times and the likelihood of giving intention increased about 3.60 times. Second, the influences of citizens' altruism and social trust on giving behavior for COVID-19 were moderated by gender and age. Whereas the influence of altruism on giving participation was more pronounced for women, the influence of altruism on giving intention was more pronounced for young citizens. Also, the influence of social trust on giving intention was more pronounced for young citizens. Based on the results, this study discussed strategies for citizens' giving behavior to overcome a disaster like COVID-19.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.3
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• pp.235-244
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• 2022

In this study, the cell viability, radical scavenging ability, elastase activity, moisturizing activity, and antimicrobial activity of mixed fermented extract of vitamin tree fruit, acai palm fruit, mango, lemon, apricot and blueberry as an active ingredient were measured. The experiment was performed at three concentrations(0.5 / 1.5 / 2%), since cytotoxicity was not shown at these three concentrations. Based on this, a radical scavenging experiment was conducted to compare with L-ascorbic acid, a representative raw material of an antioxidant material. The results showed that the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability was 95.1 ± 0.6%, 94.3 ± 0.7%, 95.3 ± 0.6%, 95.1 ± 0.7%, 95.1 ± 0.3%, 95.5 ± 0.3%, and 95.4 ± 0.4% respectively, when the concentration of the mixed fermentation extract was 2%. As the concentration increased at the three concentrations (0.5/1.5/2%) and the content of blueberry extracts increased, sample 7 showed excellent elastase activity at a concentration of 2% to 0.9 cm, such as retinol crystal, and moisturizing activity was also found to be 71.5%, 75.6%, and 81.6%, respectively. Particularly, at the 2% concentration of the mixed fermented extract, the antibacterial activity effect on Propionibacterium was very excellent in sample 7. Therefore, it is considered that it is worth developing the mixed fermented extracts of 2% concentration as a cosmetic component with antioxidant, moisturizing, and antibacterial properties.

• The Journal of the Korea Contents Association
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• v.21 no.11
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• pp.773-784
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• 2021

This study aimed to examine the mediation effects of foreign-born mothers' daily stress, depression, and neglectful parenting in the influence of mothers' acculturative stress on children's carrier barrier in multicultural families. For testing research questions, using Model 6 of the SPSS PROCESS Macro, this study analyzed simple and multiple mediation effects with a sample of 1,021 adolescents with Korean fathers and foreign-born mothers from the 8th wave's raw data of the Multicultural Adolescent Panel Study (MAPS). The main results are as follows. First, mothers' acculturative stress positively influenced children's carrier barrier. Second, mother's daily stress and neglectful parenting individually mediated the influence of mothers' acculturative stress on children's carrier barrier. Third, mother's depression and neglectful parenting dual-mediated the influence of mothers' acculturative stress on children's carrier barrier. Fourth, a triple mediation of mothers' daily stress, depression, and neglectful parenting was found in the influence of mothers' acculturative stress on children's carrier barrier. Based on the results, strategies to support the career development of multicultural adolescents were suggested.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.6
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• pp.371-380
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• 2023

To calculate seismic fragility, it is important to select input earthquake ground motions that can properly express the characteristics of the target site. This study analyzed the seismic fragility of a single-degree-of-freedom (SDOF) model based on input earthquake ground motions in strong and low-to-moderate seismic regions. As a first step, a total of four sets of input earthquake ground motions were selected,: two sets measured near or far from overseas strong earthquake records and two sets exhibiting the characteristics of low-to-moderate earthquake regions in South Korea. A nonlinear SDOF model for three natural periods was applied to the target structure, and incremental dynamic analysis was used for fragility analysis. In addition, four damage states were defined, and seismic fragility results for each natural period of the nonlinear SDOF model for the four aforementioned input earthquake ground motion sets were obtained for each damage state.

• Journal of radiological science and technology
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• v.31 no.4
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• pp.337-346
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• 2008

A questionaire survey was conducted for patients who had been examined at the Department of Radiology to investigate the items that need to be improved. Brainstorming was also conducted by team members to suggest the tactics that can efficiently perform the QI activity by selecting the most frequently answered topics for the reduction of waiting time of x-ray examination. From September 2006 to November 2007, number of patients before and after conducting QI was compared for 3 months by each category differentiated by types of detailed causes. A patient case was set as one shooting for one patient. After conducting QI, the waiting cases before conducting QI were evaluated for the method of improvement for 3 month through the QI team discussion and conducted by following the improvement method for the next 1 month and the waiting cases were measured and the difference before and after the QI activity was compared in percentage. 1. When patient waiting cases were compared before and after conducting QI activity against the causes of repetition, it resulted in 3.9% of reduction effect. 2. When patient waiting cases were compared before and after conducting QI activity against the causes for the lack of guiding, it resulted in 1.1% of reduction effect. 3. When patient waiting cases were compared before and after conducting QI activity against the causes of miss-inputting prescription, it resulted in 1.1% of reduction effect. 4. When patient waiting cases were compared before and after conducting QI activity against the causes for emergency patients, patients with acute pain and discomfort patients, it resulted in 12.0% of reduction effect. 5. When patient waiting cases were compared before and after conducting QI activity against the causes for shooting overlapping of outpatients and hospitalized patients, it resulted in 4.7% of reduction effect. There are many factors to reduce the patient waiting cases in radiography. The first step is for radiology department to find these factors through QI, to improve them, which is the reason why the QI team is organized to perform the QI activities.