• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.52-52
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• 2018

Apple (Malus domestica) is one of the most economically important fruits in Korea. But virus infection has decreased sustainable production of apple and caused the serious problems such as yield loss and poor fruit quality. Virus or viroid infection including Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV), Apple mosaic virus (ApMV) and Apple scar skin viroid (ASSVd) has been also reported in Korea, furthermore, its damages and economic losses have increased constantly. In our research, we tried to survey virus infection for commercial nursery trees of major apple cultivars, especially dwarfing rootstocks 'M.9' and 'M.26' as well as scions. Trees were collected from 11 locations which have produced a great amount of apple nursery stocks in Korea. Infection degree was investigated in apple cultivars, 'Hongro' and 'Fuji' using RT-PCR method. In the scion of cultivar 'Hongro', infection ratio of ACLSV, ASPV and ASGV were 100%, 81.8% and 100% respectively. In the rootstock of cultivar 'Hongro', infection ratio of ACLSV, ASPV, ASGV and ApMV were 90.9%, 81.8%, 100% and 9.1% respectively. In the scion of cultivar 'Fuji', infection ratio of ACLSV, ASPV and ASGV were 81.8%, 90.9% and 100% respectively. In the rootstock of cultivar 'Fuji', infection ratio of ACLSV, ASPV, ASGV and ApMV were 81.8%, 90.9%, 100% and 9.1% respectively. Infection of ASSVd was not detected in both cultivars. From our results, it was found that most of apple rootstocks and scions had multiple infections by apple viruses which have caused economic damage in fruit production.

• Korean Journal of Social Welfare
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• v.69 no.3
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• pp.213-240
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• 2017

In the harsh period for young adults to prepare their successful life, this study aimed to understand the specific experiences of independence transition among homeless young adults. Also this article explored how their family perform as a supportive system for their independence. Using in depth interview materials of 19~39 aged 8 young homeless males, the research analyzed their family's weak support; no family members, no economic support and breaking relationship. As to occasion of independence, the participants sometimes experienced loss of house, evacuation by their family or runaway from their home. It was abrupt and unexpected leaving home. Also their process of independence was beyond their capacity that they suffered from instability job and destitute rather than continuous mental trauma and isolation. In the end they faced serious risky situations that they cannot manage without any help. The findings of this study suggest that quality of family relationship would be more important than economic capital from family and transition to adulthood of vulnerable young adults who don't have family support need much alternative supportive system and social capital.

• Korean Journal of Health Education and Promotion
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• v.20 no.1
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• pp.203-218
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• 2003

In aging Korean society, many elderly people have difficulty in the areas of health, economic insecurity, role-loss(both work & spouse), loneliness, and family conflicts. Above all, retirement from work is one of the most important stressful life events having influences an elderly's persons economic & social activities, mental state, health status, and Lifelong educational programs could help the aged cope with these situations in later life. Health and social welfare are commonly recognized as an important value of life. They also have an effect on each other. Most people agree that the promotion of health and social welfare is to take a short-cut toward achieving well-being. Thus we need to develop a substantially integrated program of lifelong education, before and after retirement, for the promotion of health and welfare. Universities have the advantage of practicing lifelong educational programs because they have more material, intellectual, and human resources than any other educational facilities. As a result, the purposed of this study is to suggest life-long educational programs for promoting both health conditions and the level of social welfare by utilizing an aging center affiliated with a university. Specifically, the developmental courses of pre-retirement, learning in retirement, elder-hostels, and the connection between pre and post-retirement educational programs are proposed in this study.

• Resources Recycling
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• v.21 no.6
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• pp.23-31
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• 2012

Removal work about weeds that grow naturally on road and industrial complex is attaining ordinary times but is suffering difficulty in weeding work by strong self-generation power. In the meantime, going side by side with these manual processing and weeding work through construction of weed-proof seat is attaining, but economic performance, limitation of application region and withdrawal processing problem are being blamed for shortcoming. The scope of this study is about the manufacture of weed-proof mortar using eco-friendly industrial byproducts characterized by an economic and simplicity for not limited to loss of function as a product recovered after treatment. After the carried out the various experiments and actual construction for the selection of mixing materials and derivation of appropriate mix, through the comparison and analysis of results, it was investigated the research results of weed-proof mortar for fundamental development.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1483-1489
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• 2015

The purpose of this study is to investigate the changes in citizens' perceiving urban landscape. To this end, the citizens' perceptions of urban landscape of Gimhae were surveyed two times in 2003 and 2011. To examine the statistical significance, the frequency analysis, the chi-square test were applied. There were small changes of opinion between two periods caused by the change of city form, an increase in interest in the living environment, environmental protection and so on. The interest of the citizens of the landscape were high. Citizens showed a negative feedback with respect to economic sacrifice. So, regulation causing citizens' economic loss should be avoided and It is effective to establish policies to support and induction. The results of this study are intended to be used as a reference to the planning urban landscape.

• Economic and Environmental Geology
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• v.52 no.5
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• pp.471-484
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• 2019

Liquefaction occurs by a temporal loss of sediment strength as a consequence of increased pore water pressure during the re-arrangement of unconsolidated, granular sediments. Liquefaction is dependent on the physical properties of the sediments and cause surface cracks, landslide, and the formation of soft-sediment deformation structures(SSDS). SSDS is formed by the combined action of the driving force and deformation mechanism(liquefaction, thixotropy, and fluidization) that is triggered by endogenic or exogenic triggers. So research on the SSDS can unravel syndepositional geological events. If detailed sedimentologic analysis together with surrounding geological context suggest SSDS formed by earthquakes, the SSDS provide a clue to unravel syndepositional tectonic activities and detailed paleoseismological information(> Mw 5) including earthquakes that leave no surface expression.

• Journal of Animal Science and Technology
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• v.63 no.5
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• pp.1098-1113
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• 2021

Maturation process of alfalfa (Medicago sativa L.) could be prevented by the reduction of lignin content in terms of conventional breeding or transgenic technology. Alfalfa could exhibit higher leaf/stem ratio, with a concern of yield loss. The objective of this study was to compare forage yield and nutritive value of low lignin alfalfa and two reference varieties subjecting to two harvest intervals and three seeding rates. The experimental design was a randomized complete block in a split-split plot arrangement with four replicates, where harvest intervals (28-day and 35-day) were assigned to whole plots, seeding rates were subplots, and varieties were sub-subplots. The weighted mean nutritive value was applied to two production years of 2016 and 2017. Hi-Gest 360 (low lignin alfalfa) provided similar yield potential and increased nutritive value compared to two reference varieties. Over a two-year production period, alfalfa harvested at every 28-day interval provided more economic returns than those at 35-day interval. For the seeding year and first production year, five cuts made by the 28-day interval produced more yield than four cuts by the 35-day interval. Due to limited rainfall in May 2017, a sharp drop of the first cutting overturned the advantage of the five-cut system. Shorter intervals between harvests generally increased crude protein (CP) concentrations. The differences of relative feed value (RFV) between two harvest intervals tended to be great during the first and second cuttings. Overall, harvest interval had a large effect on nutritive value and a more significant effect on alfalfa dry matter yield than variety selection. Seeding rate did not affect alfalfa yield and nutritive value.

• Journal of dental hygiene science
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• v.19 no.1
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• pp.23-30
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• 2019

Background: The health of the economically active population contributes to increased corporate productivity by reducing the productivity loss caused by disease and increasing job efficiency, which in turn is a national benefit. Since the economically active population is a concept encompassing workers and a source of economic development for a country, that population's health should be treated with importance not only from a personal standpoint but also at a national level. Methods: In this study, data of 11,007 adults aged 20 years and older who participate in economic activities were analyzed in the five-year Korea Health Panel Study from 2010 to 2014 including the number of dental visits and dental medical expenses. Results: Factors related to "gender," "education level," "age," "duty category," "income level," "employment type," "national health insurance," and "chronic disease status" of the economically active population are affected in relation to the number of visits and dental medical expenses. The number of dental visits increased with higher education levels (p<0.001), and the number of visits to the dentist increased with older age (p <0.001). Dental medical expenses were 91,806 Korean won (KRW) more for "white-collar workers" than for "blue-collar workers" (p<0.03), and 127,674 KRW more for "regular workers" than for "atypical workers" (p<0.02). Conclusion: When it is necessary to improve policies to enhance the efficiency of the distribution of health and medical resources in the overall balance of the dental health sector, we should try to identify various factors of oral health disorder due to income inequality among the classes according to the country's employment type in order to find ways to reduce the health gap among the social classes.

• Journal of the Economic Geographical Society of Korea
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• v.23 no.4
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• pp.438-453
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• 2020

This study attempts to examine the process of place-making, to define the role and interrelationship of the subjects and to analyze the placeness of the 'Kim Gwang-seok Road', a representative example of artificial place-making. Through a 10-year urban regeneration project based on the concept of Kim Gwang-seok, the alleyway between Bangcheon Market and the retaining wall of Sincheon-daero has been embedded as a memorial space for Kim Gwang-seok and an cultural art space. However, the existing placeness has weakened as the result of the excessive tourism in the late 2010s, while the characteristics of cultural commercial space has strengthened. This change in place has prompted community disintegration, which has caused the loss of momentum for sustainable development. To overcome these problems, it will be necessary to establish endogenous governance to expand and reproduce existing community capabilities, embedded social capital and place assets in new directions.

• Plant Journal
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• v.17 no.2
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• pp.48-53
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• 2021

In the case of a 900 MW combined cycle power plant, most of the load on the site is a rotating device and is operated at a low power factor, and the power factor decrease increases the reactive power, which causes the efficiency of the device to be consumed and unnecessary unnecessary power consumption. This study intends to present the results by installing and operating a reactive power compensation device that absorbs and removes reactive power, which is a solution to this problem, on a 6.9 kV on-board bus. As a result of application of this system, first, it was confirmed that the power factor of the rotating machine was improved to 0.22 and the load power in the house was reduced by 1.4%, and the thermal efficiency of the generator was increased by 0.1% and the power generation power by 810 kW. Next, it was confirmed that the cost of construction and operation can be reduced in the future due to economic feasibility, with a decrease of 200 million won/year in electricity loss compared to 1.5 billion won in investment, an increase of 1 billion won/year in sales, and a one-year capital recovery period.