• Korean Journal of Culture and Social Issue
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• v.19 no.1
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• pp.19-44
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• 2013

The present study aimed at investigating how Korean housekeeper in midlife revaluate their lives. For this purpose, 14 housekeepers whose youngest child was at least older than high school students were interviewed in a semi-structured retrospective method. The interview was focused on relational, psychological, and economical aspects of the participants before and after marriage each. The interview usually continued one and a half to two hours. The phenomenological method describing personal meaning of experiences was referred to for data analyses by transforming retrospective life story of participants into key meaningful units. According to main retrospective contents of each stage of development, the participants' childhood and adolescence was characterized by familial circumstances, formation of personality and value, and career choice. Main themes of their early adulthood were spouse selection and marriage, marital adaptation, and family relationships. Their midlife focused on children, economic and emotional stability, family relationships, acceptance of their spouse and themselves, and health and religion. Life styles of the participants were analyzed in terms of turning events, meanings of current life, and cumulative effects of life events. These findings were discussed in terms of developmental pattern in relation to the established theory of development.

• Korean Journal of Environment and Ecology
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• v.37 no.6
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• pp.473-483
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• 2023

This study was conducted to find out the psychological or physiological healing effects of real natural forests and virtual forest experiences using virtual reality (VR) in an artificially-controlled digital environment. To find out this, 81 healthy undergraduate students from C University were experimented on visual forest stimulation effects in the digital environment from September 5 to December 9 in 2022. The experiment evaluated the psychological and physiological healing effects of visual forest stimulation in the digital forest environment (2D, 3D). The SRI (stress response inventory) experiment for analyzing psychological effect showed statistically significant differences among groups. As for the SRI experiment for measuring psychological stress, except Control group, 2D group in the digital environment showed little difference before and after the experiment. But 3D group showed less stress than before. As a result, it was proved that visual forest stimulation in a forest-based digital environment (2D, 3D) reduces psychological stress significantly. And when analyzing how visual forest stimulation changes EEG (electroencephalogram) in the digital environment, alpha waves (RA), which are activated during relaxation or stabilization, were more active than beta waves (RB), which are activated during tension or awakening. This study is expected to be used to create a psychological and physiological healing environment for those who cannot go to a natural forest due to mobility difficulties by providing them visual forest stimulation experiences in a digital environment. It is also expected that the results will be the basis for forest healing in the digital environment and virtual reality programs will help forest healing activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.109-116
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• 2008

In this study, the breads with medicinal herbs (MH) composites showing immunostimulating activity were prepared and their characteristics were examined. Fourteen kinds of medicinal herbs were extracted with hot water and divided into 3 groups (MH-1, MH-2, MH-3) based on their contents. All groups showed immunostimulating activity in terms of macrophage phagocytosis, nitrite production, cytostatic activity and cytokine production. In the preparation of breads containing MH extracts of various contents (0, 30, 50, 70, and 100%), there was no significant difference among dough pHs of all groups after first fermentation, but loaf volume was significantly (p<0.05) increased in 70% added group while decreased in 30%, 50%, and 100% added groups compared to the control. The "a" and "b" values of bread crumb increased with the content of MH extracts while "L" value decreased, but these values of bread crust were similar to the control group. Most improvements in hardness, adhesiveness, gumminess and chewiness of bread were noticed by the addition of 70% MH extracts, but those of springiness, cohesiveness and resilience were mostly by the 50% addition ones. Through the sensory evaluation, it was revealed that mouth feeling, taste and overall preference decreased at breads containing 70% and 100% extracts, although appearance and crumb texture were not significantly (p<0.05) different among all groups.

• Land and Housing Review
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• v.14 no.4
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• pp.77-93
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• 2023

The COVID-19 pandemic has brought about significant social changes through government prevention and control measures, changes in people's risk perceptions, and lifestyle changes. In response, urban inhabitants changed their behaviors significantly, including their preferences for transportation modes and urban spaces in response to government quarantine policies and concerns over the potential risk of infection in urban spaces. These changes may have long-lasting effects on urban spaces beyond the COVID-19 pandemic or they may evolve and develop new forms. Therefore, this study aims to explore the potential for urban spaces to adapt to the present and future pandemics by examining changes in urban residents' preferences in travel modes and urban space use due to the COVID-19 pandemic. This study found that overall preferences for travel modes and urban spaces significantly differ between the pre-pandemic, pandemic, and post-pandemic periods. During the pandemic, preferences for travel modes and urban spaces has decreased, except for privately owned vehicles and green spaces, which are perceived to be safe from transmission, show more favorable than others. Post-pandemic preferences for travel modes and urban spaces are less favorable than pre-pandemic with urban spaces being five times less favorable than transportation. Although green spaces and medical facilities that were positively perceived during the pandemic are expected to return to the pre-pandemic preference level, other factors of urban spaces are facing a new-normal. The findings suggest that the COVID-19 pandemic has had a significant impact on urban residents' preferences for travel modes and urban space use. Understanding these changes is crucial for developing strategies to adapt to present and future pandemics and improve urban resilience.

• Composites Research
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• v.34 no.3
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• pp.192-198
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• 2021

Due to enormous market growing of electric vehicles without combustion engine, reducing unwanted BSR (buzz, squeak, and rattle) noise is highly demanded for vehicle quality and performance. Particularly, innerbelt weatherstrips which not only block wind noise, rain, and dust from outside, but also reduce noise and vibration of door glass and vehicle are required to exhibit high damping properties for improved BSR performance of the vehicle. Thermoplastic elastomers (TPEs), which can be recycled and have lighter weight than thermoset elastomers, are receiving much attention for weatherstrip material, but TPEs exhibit low material damping and compression set causing frictional noise and vibration between the door glass and the weatherstrip. In this study, high damping EPDM (ethylene-propylene-diene monomer)/PP (polypropylene) thermoplastic vulcanizates (TPV) were investigated by varying EPDM/PP ratio and ENB (ethylidene norbornene) fraction in EPDM. Viscoelastic properties of TPV materials were characterized by assuming that the material damping is directly related to the viscoelasticity. The optimum material damping factor (tanδ peak 0.611) was achieved with low PP ratio (14 wt%) and high ENB fraction (8.9 wt%), which was increased by 140% compared to the reference (tanδ 0.254). The improved damping is believed due to high fraction of flexible EPDM chains and higher interfacial slippage area of EPDM particles generated by increasing ENB fraction in EPDM. The stick-slip test was conducted to characterize frictional noise and vibration of the TPV weatherstrip. With improved TPV material damping, the acceleration peak of frictional vibration decreased by about 57.9%. This finding can not only improve BSR performance of electric vehicles by designing material damping of weatherstrips but also contribute to various structural applications such as urban air mobility or aircrafts, which require lightweight and high damping properties.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.1
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• pp.46-58
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• 2024

Pollinators are organisms that carry out the pollination process of plants and include Hymenoptera, Lepidoptera, Diptera, and Coleoptera. Among them, bees not only pollinate plants but also improve urban green spaces damaged by land use changes, providing a habitat and food for birds and insects. Today, however, the number of pollinating plants is decreasing due to issues such as early flowering due to climate change, fragmentation of green spaces due to urbanization, and pesticide use, which in turn leads to a decline in bee populations. The decline of bee populations directly translates into problems, such as reduced biodiversity in cities and decreased food production. Urban beekeeping has been proposed as a strategy to address the decline of bee populations. However, there is a problem asurban beekeeping strategies are proposed without considering the complex structure of the socio-ecological system consisting of bees foraging and pollination activities and are therefore unsustainable. Therefore, this study aims to analyze the socio-ecological system of honeybees, which are pollinators, structurally using system thinking and propose a green space planning strategy to revitalize urban beekeeping. For this study, previous studies that centered on the social and ecological system of bees in cities were collected and reviewed to establish the system area and derive the main variables for creating a causal loop diagram. Second, the ecological structure of bees' foraging and pollination activities and the structure of bees' ecological system in the city were analyzed, as was the social-ecological system structure of urban beekeeping by creating an individual causal loop diagram. Finally, the socio-ecological system structure of honey bees was analyzed from a holistic perspective through the creation of an integrated causal loop diagram. Citizen participation programs, local government investment, and the creation of urban parks and green spaces in idle spaces were suggestedas green space planning strategies to revitalize urban beekeeping. The results of this study differ from previous studies in that the ecological structure of bees and the social structure of urban beekeeping were analyzed from a holistic perspective using systems thinking to propose strategies, policy recommendations, and implications for introducing sustainable urban beekeeping.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.113-122
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• 1986

In order to promote mechanization of corn harvesting in Korea, this study was conducted to find out the effect of moisture content on compressive properties such as force, deformation, energy and modulus of stiffness to the bioyield and the rupture point for Korean corn kernel. In this study, the loading positions of corn were flat, edge, longitude and the moisture contents were about 13, 17, 21, 25% in wet basis. The compression test was carreied out with flat plate by use of dynamic straingage for three varieties of Korean corn under quasi-static force when the loading rate was 1.125mm/min. The results of this study are summarized as follows; 1. When the moisture content of corn ranged from 12.5 to 24.5 percent, at flat position, the bioyied force was in the range of 13.63-26.73 kg and the maximum compressive strength was in the range of 21.55-47.65kg. Their values were reached minimum at about 17% and maximum at about 21% moisture content. The bioyield force was in the range of 13.58-6.70kg at edge position and the maximum compressive strength which was 16.42 to 7.82kg at edge position was lower than that which was 18.55-9.05kg at longitudinal position. 2. Deformation of corn varied from 0.43 to 1.37 mm at bioyield point and from 0.70 to 2.66mm at rupture point between 12.5 to 24.5% moisture content. As the moisture content increased, deformation was increased. 3. The moduli of resilience and toughness of corn ranged from 2.60 to 8.57kg. mm and from 6.41 to 34.36kg. mm when the moisture content ranged from 12.5 to 24.5 percent, respectively. As the moisture content increased, the modulus of toughness was increased at edge position and decreased at longitudinal position. And their values were equal each other at 22-23% moisture content. 4. The modulus of stiffness was decreased with increase in the moisture content. Its values ranged from 32.07 to 5.86 kg/mm at edge position and from 42.12 to 18.68kg/mm at flat position, respectively. Also, the values of Suweon 19 were higher than those of Buyeo. 5. It was considered that the compressive properties of corn at flat position were more important on the design data for corn harvesting and processing machinery than those of edge or longitudinal position. Also, grinding energy would be minimized when a corn was processed between about 12.5 to 17% moisture content and corn damage would be reduced when a corn was handled between about 19 to 24% moisture content in wet basis.