• Journal of Korea Foundry Society
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• v.41 no.5
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• pp.411-418
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• 2021

In order to experimentally investigate the effect of Ni or Cu addition on microstructure and mechanical properties of high Si Solution Strengthened Ferritic Ductile cast Iron (SSF DI), a series of lab-scale sand casting experiment were conducted by changing initial concentration of Ni up to 3.0wt% or Cu up to 0.9wt% in the alloy. It was found that increase in Ni or Cu content in the alloy leads to increase in strength properties and hardness as well as decrease in ductility. The higher Ni or Cu content the SSF DI has, the higher fraction of pearlite was observed. At similar levels of Ni or Cu contents in the alloy, higher pearlite area fraction was observed in the Cu-containing SSF DI than that in the Ni-containing SSF DI. When the effect of the microstructure on the mechanical properties of Ni-containing SSF DI was considered, Ni-containing SSF DI was found to have excellent strength and hardness as well as good elongation when the pearlite fraction was controlled less than 10%. As the pearlite fraction in the Ni-containing SSF DI exceeds 10%, however, it shows drastic decrease in elongation. Meanwhile, gradual increase in strength and hardness, and decrease in elongation with respect to increase in pearlite fraction were observed in Cu-containing SSF DI. The different microstructure-mechanical property relationships between Ni-containing and Cu-containing SSF DI were due to the combined effect of the relatively weak pearlite stabilizing effect of Ni compared to that of Cu in high Si SSF DI, and matrix strengthening effect caused by the different amounts of those alloying elements required for similar pearlite fraction.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.2
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• pp.155-170
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• 2021

Oats (Avena sativa L.) represent a good forage crop for cultivation in regions with short growing periods and/or cool weather, such as the mountainous areas of southern Korea. In this study, using the Korean elite summer oat varieties 'High speed' and 'Dark horse', we aimed to determine the optimal time to plant and harvest forage oats seeded in spring and summer in a mountainous area. Seeds were planted three times from late February and early August at 9- or 10-days intervals, respectively, and plants were harvested three times from late May to October at 10-day intervals. The experiment was carried out in an upland field (Jangsu-gun Jeonbuk) in 2015 and 2016. We investigated the changes in forage yield (FY) and quality [crude protein (CP) and total digestible nutrient (TDN) contents] based on the time of planting and harvest. Neither the forage quality nor yield of either spring and summer oats was significantly influenced by the time of planting. The CP of spring oats harvested three times at 10-day intervals from late May was 12.0%, 8.2%, and 6.5%, thereby indicating a reduction with a delay in the time of harvest. In summer oats, CP ranged from 8.4% to 8.7%, although unlike CP in spring oats, was not significantly influenced by the time of harvest. For both forage types, harvest time had no significant effect on TDN. The FY of spring oats harvested in late May and early and mid-June was 10.2, 18.7, and 19.5 ton ha^-1, respectively, with that of oats harvested on the latter two dates being significantly increased by 83% and 91%, respectively, compared with that in late May. Similarly, the FY of spring oats harvested in late October and early and mid-November was 7.1, 12.5, and 12.1 ton ha^-1, respectively, with that of oats harvested on the latter two dates being significantly increased by 75% and 71%, respectively, compared with that in late October. Taking into consideration forage yield and quality (not less than 8% CP), it would be profitable to plant spring oats in the mountainous areas of southern Korea until March 15 and harvest around June 10, whereas summer oats could be beneficially planted until August 25 and harvested from early November.

• Journal of Korean Medical Ki-Gong Academy
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• v.8 no.1
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• pp.96-114
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• 2005

This study was carried out to provide essential data for the future health promotion projects to be aimed at improving quality of life for the elderly people in the increasingly aging society of Korea by investigating factors related to the yangseng of old people in urban areas. The results of this study are to be used as basis for efficient approach toward health promotion projects for the elderly in urban communities. For the purpose, a survey by questionnaires was conducted to urbanites from May th June 2004. The collected replies were analyzed from the viewpoints of Oriental Medicine for yangseng. 1. The average points of health care were 3.24. In details by sub-areas, 3.78 was rated for morality yangseng, 3.29 for mind, 3.30 for diet, 3.79 for activity and rest, 2.32 for exercise, 3.72 for sleeping, 2.95 for season and 1.81 for sexual life, which showed that the area of activity and rest yangseng was scored highest while the area of sexual life yangseng was rated lowest. 2. As for the extent of health care depending on the characters of subjects, higher scores were rated by men than women, younger ones than aged and spoused ones than singles. Married couples living without other family members were found to yangseng most, while more yangseng was taken by the educated, job holders and those who utilize leisure and have religion in order. 3. Men exercised more yangseng than women in the diet, exercise and sleeping. By age, the group aged 65 to 69, the more yangseng in the exercise and sexual life. The group with spouse featured higher concern for yangseng in all categories except for season. Married couples who are living with no other family members recorded the highest point in all areas except for exercise. 4. The more one is educated, the more he/she is tended to take yangseng in the sub-areas of exercise and sexual life. The group with occupation is also inclined to take more yangseng in the same sub-areas as those of the highly educated. When they pay living cost together with offspring, they appeared to be the most yangseng in season and sexual life. People who enjoy leisure showed higher yangseng in all areas except for season. Religion had a significant influence in all areas except for activity and rest yangseng. 5. Those who reply that they are confident with health and have no disease proved to have higher yangseng. Depending on whether one has disease or not, higher yangseng was confirmed in such sub-categories as mind and sleeping. Those who replied they are confident with health had higher yangseng in all areas except for season. As seen above, yangseng of the old people in the urban area is found to have different extent depending on the individual and socioeconomic characters, factors which should be seriously considered in the local health promotion projects and projects for the health of the elderly. It seems therefore necessary to launch health promotion programs and to analyze their effects to promote health care particularly in the areas of sexual life, exercise and season yangseng that featured lowest grade of yangseng in each sub-area.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.40-55
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• 2015

This study aims to evaluate the efficiency of the forest experience center for children led by the local community as experiential management for forest kindergarten education. For this, an importance and performance analysis was conducted on the forest experience center for children in Geumcheon-gu, which, of the 12 forest experience center for kids in Seoul, is the only one led by the local community. The questionnaire sheet for the analysis consisted of a total of 36 questions, 20 about place facility areas and 16 about management program areas(including 6 questions about the management led by the local community). The questionnaire survey was done during the period between January 12th and January 19th, 2015. The participants in the survey consisted of 15 forest education specialists and 50 teachers from 19 kindergartens who participated in the forest experience program. The number of questionnaire sheets collected and used for analysis was 13 copies and 43 copies, respectively. The mean values of importance and performance on the place facility areas were 4.07 and 3.78 for forest education specialists, and 4.16 and 3.84 for kindergarten teachers, respectively. The mean values of importance and performance regarding the management program area were 4.38 and 4.16 for forest education specialists, and 4.40 and 4.00 for kindergarten teachers, respectively. Both groups evaluated the place facility areas lower than the management program areas. They also evaluated performance lower than importance. In place facility area, 'accessibility', 'safety' and 'connectivity to forest trail', 'loose parts' and 'safety facilities' were required to 'keep up the good work', because they showed higher importance and performance in place facility areas. Even though most items of management as led by the local community including 'forest experience activity support' were evaluated as 'important', some, including 'effort for local revitalization', were evaluated as low in performance. However, as they were evaluated as higher in importance, if they pursue 'concentrate here', it is expected that they will be evaluated as higher in performance. In addition, considering that program areas including 'forest education specialist's role' are labeled under the management led by the local community, it reflected a positive evaluation. As a result, management led by the local community is efficient as a management system for the forest experience center for children in an experiential forest kindergarten education. Going forward, if this management system is durable in 'keep up the good work' and 'concentrate here', the forest experience center for children led by the local community will be an alternative for an effective experiential forest kindergarten education.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3688-3699
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• 2010

The purpose of this study is to understand attributes, stress and burnout related to job environment of healthcare facilities workers for the aged, care-givers, analyze the effect of these factors on job satisfaction, and improve their organizational task to help advance the quality of life and the healthcare facilities for the aged. A survey was made on 129 care-givers working in the healthcare facilities for the aged(care facilities, in-home facilities for the aged) located in Jeonbuk Gunsan area. This study showed that sub-factors of care-givers' job environment such as human environment, compensation system and job expertise have a significant effect on the job burnout, stress and satisfaction. This means that a well-organized compensation system, which is proportionate to the job expertise and ability for human environment, and achievement of innovative thinking, will make a positive relationship, reduce the job burnout and stress, and improve the job satisfaction at the same time. Compared to the rapid increase of old aged patients for long-term care and care-givers' real role and job in the facilities, the job specialization has to be guaranteed to improve job environment of care-givers as various beneficial workers for welfare - professional workers - and the compensation system needs to be properly systematized according to their job capacity. Consequently, the production and participation of professionals with high self-esteem may raise organizational commitment through the maximization of job satisfaction by the participation and devotion to the organization of more professionals by removing factors, which can reduce the frequent job burn-out and stress of care-givers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.61-69
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• 2020

This paper examined the operational efficiency of the new rice variety "Sindongjin" farmed by the Rural Development Administration. Thirty farmers were surveyed in the survey area--Jeonbuk-do Province. The operational efficiency was analyzed by studying the data of these 30 farmers. The operational efficiency of the farmers was analyzed through a survey using the DEA model for analysis. DEA analysis was performed to obtain the technical efficiency of the farmers. The results showed that the DEA technical efficiencies of 12 farmers were efficient, and 18 farmers were inefficient. Farmers No. 13 and No. 25 were representative of inefficiency, and the results show that the cost of input elements was high. An analysis of the determinants of efficiency through the Tobit model found that the operating efficiency increased with decreasing variable costs (Seed costs, By-product fertilizer costs, General fertilizer cost, Pesticides cost, Cost of water, electricity, gas, and Cost of small farm implements) and fixed costs (Repair cost and Other costs). There is a problem of excess input from farmers, and these input costs need to be reduced.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.2
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• pp.128-136
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• 2014

It is known that the best way to recycle fly ash is to use in concrete. It is impossible to bury in the ground this fly ash recently, so it is trying to use high volume fly ash concrete. Nevertheless, recent main research topics are focused in the part of material only. However, it is necessary to perform the researches about elasticity modulus, stress-strain relationship and structural behavior. Therefore, in this paper, 18 test members were manufactured with 3 test variables, namely fly ash replacement ratio 0, 35, 50%, concrete compressive strength 20, 40, 60MPa and 2 tensile steel ratio. 18 test members were tested for flexural behavior. From the test results, there were no differences between 35, 50% high volume fly ash cement concrete and ordinary concrete without fly ash (FA=0%). In order to evaluate the HVFAC flexural behavior, Analytical model was proposed and the computer program was developed. There were no differences between test results and analysis results. So, the proposed analytical model was reasonable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.490-498
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• 2016

This study aimed to investigate the relation between self-esteem and satisfaction. After gathering study subjects (exercise participants) and deciding the population in 2014 in Jeonbuk city area, convenience sampling method was used to analyze the date from 278 subjects. The retrieved questionnaire in the research was analyzed in Window SPSS version 21 statistical program. Frequency analysis, exploratory factor analysis, reliability analysis, and correlation analysis were used to find correlations between test values. Multiple regression analysis was used to find the effects of the test values. The study results are as follows. First, the exercise participants' positive self-esteem exhibited a positive relationship with competence, relatedness, and autonomy, which are sub factors of basic psychological needs satisfaction. Also, negative self-esteem had a negative relationship with competence, relatedness, and autonomy. Second, exercise participants' self-esteem had a positive effect on competence and autonomy in positive self-esteem and a negative effect on negative self-esteem. Relatedness had a positive effect in positive self-esteem but not in negative self-esteem. Thus it is necessary to increase positive self-esteem and make various exercise programs about basic psychological needs satisfaction of the exercise participants and strategic activity guide for exercise participants participating in exercise consistently.

• Korean Journal of Agricultural and Forest Meteorology
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• v.20 no.4
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• pp.313-320
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• 2018

In the spring of 2018, opened-flowers of fruit trees were frozen to death due to abnormal low temperature around Jeonbuk Province and southern Gyeonggi Province areas. In the 2000s, abnormal weather is observed all over the world very frequently. As a consequence, various sectors of the society suffer from economic damage and negative effects of the abnormal weather. Moreover, recent global climate change is believed to increase the incidence of extreme weathers, which are out of the normal range of the local climate. It is necessary to identify these abnormal weather phenomena accurately and analyze the effects of them on crops in order to understand the effects of them on crop yields. This study projected the trend of the low-temperature occurrence in the future by predicting the changes in future flowering dates and quantifying the temperature distribution after flowering using climate change scenarios. This study targeted areas actually producing a major portion of pear, peach, and apple in South Korea. The results of this study predicted that the flowering dates of these fruits will be approximately 20 days earlier than the current normal year in the future (2071-2100) for the study area. Moreover, it was found that the distribution of low temperature would vary by fruit type and region to some degree. The results of this study present only a portion of fruit trees cultivars grown in South Korea. It was expected that, when this approach is applied to various crops and fruit trees, it will be possible to contribute to preparing countermeasures for climate change in the agricultural sector.

• Journal of the Korean Institute of Rural Architecture
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• v.24 no.1
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• pp.27-36
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• 2022

Currently the population of rural areas in Korea continue to decline due to low birth rate, aging population, and migration. This phenomenon is accelerated over time. And as a result, there are some declining phenomenon in rural society. And it is same in the residential and basic living conditions of rural villages. The increase ratio of empty houses exacerbates the rural landscape, acts as a cause of crime and bring out various social and economic problems such as worsening settlement conditions and local slums. The study is carried out to prevent this phenomenon by investigating the architectural contents of empty houses in the village, surveyed residents and owners and finally analyzed and synthesized to make a plan to utilize empty houses in the village. This study was conducted from June to December 2021. The conclusions are followings: 1. The empty houses in Korea were 1,511 million in 2020, 8.2% of the total number of houses, whereas those in Jeollabuk-do were 95,412, 12.9% of those of houses, and those in Gimje-city, the subject of this study, were 5,944. It is up to 15.8%. In particular, empty houses in Hacheon village, the site of this study, accounted for the highest ratio, with 25% of the total number of houses. 2. To understand the utilization and improvement of empty houses, surveys and interviews were conducted to residents and owners of Hacheon village in Gimje, and most of the residents submit proposals that empty houses were not desirable in terms of village landscape and safety. The owners don't have intentions of selling or leasing them. They want to remodel them and rent for a specific period. 3. As the physical condition of the empty houses(9empty houses) 6 empty houses of them are good. 4 of them are in poor condition. 4. By synthesizing these contents, nine empty houses in Hacheon village will be remodeled as the space for those of rural start-up young people, smart farm area, community space and rental housings for rural returnees.