• Journal of Environmental Impact Assessment
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• v.28 no.1
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• pp.23-34
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• 2019

Global warming becomes a serious issue that poses subsidiary issues like a sea level rise or a capricious climate over the world. Because of severe heat-wave of the summer in Korea in 2016, a big attention has been focused on urban heat island since then. Not just about heat-wave itself, many researches have been concentrated on how to adapt in this trendy warming climate and weather in a small scope. A big part of existing studies is mitigating "Urban Heat Island effect" and that is because of huge impervious surface in urban area where highly populated areas do diverse activities. It is a serious problem that this thermal context has a high possibility causing mortality by heat vulnerability. However, there have been many articles of a green infrastructures' cooling impact in summer. This research pays attention to measure cooling effect of a street planting considering urban canyon and type of green infrastructures in neighborhood scale. This quantitative approach was proceeded by ENVI-met simulation with a spatial scope of a commercial block in Seoul, Korea. We found the dense double-row planting is more sensitive to change in temperature than that of the single-row. Among the double-row planting scenarios, shrubs which have narrow space between the plant and the land surface were found to store heat inside during the daytime and prevent emitting heat so as to have a higher temperature at night. The quantifying an amount of vegetated spaces' cooling effect research is expected to contribute to a study of the cost and benefit for the planting scenarios' assessment in the future.

• Korean Journal of Veterinary Service
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• v.42 no.1
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• pp.1-7
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• 2019

Porcine reproductive and respiratory syndrome (PRRS) is economically the most important and challenging disease in swine industries worldwide and caused by PRRS virus (PRRSV). Previous studies reported that pigs with heterozygous genotypes in the guanylate-binding proteins (GBP1 and GBP5) exhibited increased resistance against PRRSV infection. The present study was conducted to produce higher numbers of the heterozygous pigs based on the PRRS resistant polymorphisms found in GBP1 (GBP1E2 and WUR) and GBP5, and evaluate the resistance of heterozygous pigs against challenge with a type 2 PRRSV (JA142) in comparison with homozygous pigs. In the challenge study, 12, 4 week-old PRRSV-negative piglets were selected based on the genotypes of the 3 polymorphisms (GBP1E2, WUR and GBP5). Among them, 8 piglets [homozygous (n=4) and heterozygous (n=4)] were challenged with JA142 and kept in the same room, and the remaining 4 piglets were kept separately as a negative control. In results, the sperms collected from the boars of GBP1E2-GG genotype produced approximately 28~41% higher numbers of heterozygous piglets as compared with those from the boars of GBP1E2-AG genotype. In the challenge study, we found that heterozygous piglets showed the significantly lower levels of viremia than homozygous piglets at 14, 21 and 28 dpc. Consistently, these heterozygous piglets also exhibited significantly higher ADWG than homozygous piglets. Therefore, in the current study, selection of boars based on SNP markers could increase the production of PRRS resistant piglets and the PRRS resistant pigs were found to be more resistant to PRRSV infection.

• Journal of Applied Biological Chemistry
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• v.64 no.2
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• pp.159-164
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• 2021

Heavy metals exist in soils in various chemical forms including free metal ions and organo-metal complexes. The ratio of free metal ions has been known to be highly associated with the plant absorption of heavy metals. This study aims to understand the effect of free ions and organo-metal complexes on the absorption of lead (Pb) and cadmium (Cd) by plants. For this, lettuce grown in a hydroponic system for 28 days was consequently grown another 48 hours using Pb and Cd solutions. The ratios of free ion to organo-metal complexes in the solutions were adjusted at 100:0, 90:10, 70:30, 60:40 by four different organic acids (citric, oxalic, acetic, and humic acid). After that, the concentration of Pb and Cd in lettuce were analyzed. The Pb and Cd absorption by lettuce was more relied on the types of organic acids treated and the type of metals rather than the ratio of free metal ions. For example, citric acid increased the Pb absorption while it decreased the Cd absorption by lettuce. There was no significant relationship between free metal ion ratios and both Pb and Cd uptake by lettuce. It could be explained that citric acid, a relatively higher molecular weight organic acid, has higher ion binding capacity, so it forms organo-Pb complex easily due to the higher affinity of Pb on the binding site in comparison with Cd. Consequently, this complexation would assist Pb uptake by lettuce.

• Journal of agricultural medicine and community health
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• v.47 no.2
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• pp.109-120
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• 2022

Objectives: The purpose of this study was to identify the effectiveness of COVID-19 vaccinations on deaths of the COVID-19 cases in some elderly long-term care facilities (LTCF) in Gwangju Metropolitan City. Methods: The study subjects were 659 COVID-19 cases in residents of 7 elderly LTCF, Gwangju, from 21 Dec. 2021 to 28 Jan. 2022. The used variables were confirmed dates for COVID-19, demographic characteristics, co-morbidities, presentation of symptoms, death and vaccination related characteristics including type of vaccine, doses and dates. Vaccination status were classified as not vaccinated, partially and fully vaccinated. The associations of vaccination status and deaths of COVID-19 cases were tested by chi-square test and multiple logistic regression analysis. Results: The rates of not vaccinated, partially vaccinated and fully vaccinated were 19.4%, 10.2% and 70.4%, respectively. The mortality rate of the cases was 6.4%. The death rate by vaccination status was 16.4% in not vaccinated, 15.4% in partially vaccinated and 2.6% in fully vaccinated, showing a statistically significant difference. The adjusted odds ratios (ORs) (95% confidence intervals, CIs) of death compared to fully vaccinated were 7.64 (3.87-16.34) in non-vaccinated, and 6.97 (3.44-14.14) in partially vaccinated. Conclusions: COVID-19 vaccination seems to work effectively in preventing deaths of COVID-19 cases of elderly LTCF residents. This finding support that fully vaccinations in high risk group such as elderly LTCF residents is very important for one of strategies of COVID-19 management.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.5
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• pp.54-68
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• 2022

This study proposes urban development concept and strategies for Garden City, focused on Solaseado, Yeongam Heanam Tourism-Leisure Type Enterprise City in Korea. Understanding that an essential element of a garden is the endless care performed by gardeners, the Garden City development concept suggests applying this idea to making planned cities by cultivating the potential natural landscape of the site in the long run. The meaning of Garden City can be defined in three aspects; an attitude and process of planning a city, a system for constructing the spatial structure of a city, and city branding. A Garden City is a city structured with the spirit of a garden, a city where open space networks become the urban structure, and a city that builds its identity through the landscape, respectively. From this point of view, the research draws development strategies with spatial design examples to embody the Garden City concept in Solaseado by following three steps; establishing the main urban axes, creating city networks through the conjunction of the axes, and categorizing and systematizing open spaces within the city. Consequently, the study shows an alternative urban planning model that extends the concept of a Garden City while maintaining the intrinsic landscape as an urban resource. In addition, the conceptual master plan of Solaseado will structure the urban landscape and park system according to the Garden City strategies.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.1
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• pp.38-44
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• 1994

The study was conducted to investigate some grain quality characters related with brewing fittness for rice wine by adopting eight rice varieties as materials. Six japonica rice varieties except two Tongil-type rice had short and round grain of 1.80 or lower grain length/width ratio. 1000-grain weight of brown rice was 21.7~29.5g of significant difference among varieties. The white-center of rice grain was most severe in Hidahomare and Iri 402. Among tested varieties, Seomjinbyeo, Iri 402, Dongjinbyeo and Hidahomare had 50% or higher head rice ratio, while the others had relatively worse milling properties resulted from higher ratio of notched-belly and broken grain. Chemical components and total acid and amino acid content of refined rice wine was relatively good in every variety. Liquifying and saccharificating power was higher and koji conditon was also good in the varieties of high head rice ratio. Seomjinbyeo, Dongjinbyeo and Iri 402 was preferred in sensory test of refined wine and was recognized as superior adaptable rice varieties for brewing rice wine.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.677-696
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• 2022

Development of radish collectors may enhance radish production and promote upland crop mechanization in the Republic of Korea. Theoretical analysis of power is crucial to ensure the optimum design of agricultural machinery. The aim of the present study is to analyze theoretically the power requirement of a tractor-mounted radish collector under development and to propose design guidelines. The important components of the radish collector were belt-type conveyors, three hydraulic motors, and a direct current (DC) winch motor to operate the total radish collecting process. Theoretical equations were used to calculate the hydraulic motor's power, winch motor power, and draft power at loaded and unloaded conditions. A variety of tractors (44 - 74 kW) and different soil characteristics (hard, firm, tilted, and sandy) were considered to investigate the appropriate drawbar power. Variations of the power requirement of the tractor-mounted radish collector were observed due to modifications of the design parameters. The required hydraulic power of the stem cutting conveyor, stem cutting blade, and transfer conveyor of the radish collector were 0.23 and 0.24, 0.18 and 0.19, and 0.19 and 0.22 kW under unloaded and loaded conditions, respectively. The maximum draft power was calculated as 0.89, 1.07, 1.25, and 1.61 kW at a 30° tilted angle for hard, firm, tilted, and sandy soil, respectively. The calculation showed 2.07 kW DC power was required for unfolding or folding the stem-cutting conveyor. A maximum power of 4.78 kW was prescribed for conducting the whole process of the tractor-mounted radish collector. The analysis of power introduced in this study will be helpful to select the appropriate design parameters for the successful development of a tractor-mounted radish collector.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.225-240
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• 2022

Gyeonggi-do comprises several types of areas, including urban, semi-urban, and rural areas. The availability of public transportation services varies depending on the area types, but the fare structure is based on a simple transfer rule, i.e., a transfer is free when completed within 30 minutes. As a result, users in non-urban areas with a poor frequency of public transportation services do not receive transfer discounts because most of the bus routes in these areas have a gap of more than 30 minutes between services. In terms of equality of opportunity, the transfer rule is being applied unfavorably and, as a result, equality of opportunity of the non-urban commuter is severely affected. Therefore, this study analyzed the user benefits mainly stemming from transfer fares using the smart card data of commuters using public transportation in Gyeonggi-do. An index called the beneficiary rate of the free transfer was developed and a scenario analysis was conducted based on the various levels of the rate. The results of this analysis proved that the users of public transportation services in non-urban areas in Gyeonggi-do can only receive transfer benefits by the extended time for free transfer and not by the implementation of a uniform policy irrespective of the type of area. The study also suggested an equitable fare transfer system and policy alternatives.

• Computers and Concrete
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• v.31 no.4
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• pp.337-348
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• 2023

Shear wall is commonly used as a lateral force resisting system of concrete mid-rise and high-rise buildings, but it brings challenges in providing relatively large space throughout the building height. For this reason, the structure system where the upper structure with bearing, non-bearing and/or shear walls that sits on top of a transfer plate system supported by widely spaced columns at the lower stories is preferred in some regions, particularly in low to moderate seismic regions in Asia. A thick reinforced concrete (RC) plate has often been used as a transfer system, along with RC transfer girders; however, the RC plate becomes very thick for tall buildings. Applying the post-tensioning (PT) technique to RC plates can effectively reduce the thickness and reinforcement as an economical design method. Currently, a simplified model is used for numerical modeling of PT transfer plate, which does not consider the interaction of the plate and the upper structure. To observe the actual behavior of PT transfer plate under seismic loads, it is necessary to model whole parts of the structure and tendons to precisely include the interaction and the secondary effect of PT tendons in the results. This research evaluated the seismic behavior of shear wall-type residential buildings with PT transfer plates for the condition that PT tendons are included or excluded in the modeling. Three-dimensional finite element models were developed, which includes prestressing tendon elements, and response spectrum analyses were carried out to evaluate seismic forces. Two buildings with flat-shape and L-shape plans were considered, and design forces of shear walls and transfer columns for a system with and without PT tendons were compared. The results showed that, in some cases, excluding PT tendons from the model leads to an unrealistic estimation of the demands for shear walls sit on transfer plate and transfer columns due to excluding the secondary effect of PT tendons. Based on the results, generally, the secondary effect reduces shear force demand and axial-flexural demands of transfer columns but increases the shear force demand of shear walls. The results of this study suggested that, in addition to the effect of PT on the resistance of transfer plate, it is necessary to include PT tendons in the modeling to consider its effect on force demand.

• Journal of the Korean Society of Food Culture
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• v.24 no.6
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• pp.805-812
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• 2009

The consumer acceptance of food is not only affected by the sensory characteristics of food but also by the non-food factors, including food experience, consumption frequency, and food attitudes. Therefore, food attitude scales such as the food neophobic scale, VARSEEK scale, Dutch restrained eating scale, health taste attitude scale, etc. have been developed and effectively used to predict consumer liking and behaviors. Since the globalization of Korean food is currently one of the hottest topics in the Korean food industry, the aim of this study was to identify the tastes and flavors that may represent Korean cuisine. Additionally, an attitudinal scale for Korean taste and flavors was developed, which can then be utilized to predict a consumer's liking of Korean food. In the first stage of the experiment, the representative taste and flavors of Korean cuisine was surveyed by a Korean culinary expert group (n=23) and general consumers (n=62). As a result of these surveys, 4 types of flavors, hot pepper flavor, 'goso' flavor, garlic flavor, and fermented flavor were shown to be the most representative flavors of Korean cuisine. Based on these results, the second stage of the experiment was carried out to develop an attitudinal scale for Korean style flavors. Eleven to 17 questionnaires were developed for each of the 4 types of flavors. The survey consisted of a total of 53 questionnaires and 154 female consumers and 158 male consumers participated in the survey. The data was analyzed by factor analysis. For each type of flavor, the final attitudinal questionnaires were selected based on the following criteria: 1. high absolute factor loading value, 2. carrying clear meaning of the corresponding flavor attitude, and 3. delivering the meaning sufficiently when translated into other language. The final Korean style flavor attitude scale consisted of 7 hot pepper flavor, 6 'goso' flavor, 6 garlic flavor, and 7 fermented flavor questionnaires. In the next step of this study, experiments will be carried out to validate the Korean style flavor attitude scale.