• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.193-203
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• 2015

In this study, effects of buildings and topography on observation environment of weather stations located on mountainous terrain in metropolitan areas are investigated using a computational fluid dynamics (CFD) model. In order to investigate the characteristics of flow pattern around the weather stations, geographic information system (GIS) data are used to construct surface boundary input data of the CFD model. In order to evaluate effects of buildings and topography on wind speed and direction at three weather stations located in Deajeon, Busan, and Gwangju., target areas around the weather stations are selected and 16 cases with different inflow directions for each target area are considered. The simulated wind speed and direction at the weather stations are compared with those of inflow. As a whole, wind speed at the weather stations decreases due to drag effects of the buildings and topography in the upwind regions. This study shows that GIS data and the CFD model are successfully applicable to evaluation of observation environment for weather stations.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.453-461
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• 2019

This study was conducted to monitor the soil characteristics and growth of Pinus densiflora and to determine the effect of soil characteristics on growth rate five years after an ecological restoration project in Baekdudaegan ridge including Ihwaryeong, Yuksimnyeong, and Beoljae sites. The ecological restoration project was executed with the forest of P. densiflora in 2012-2013. In April 2018, we collected soil samples from each site and measured the height and the diameter at breach height (DBH) of P. densiflora. Although there was no significant change of soil pH compared to the early stage of restoration (one year after the project), it was high in Ihwaryeong, and Beoljae with values of 7.7 and 6.4, respectively. Also, the organic matter decreased by 70-80%, and the available phosphorus (P) was unchanged in three restoration sites. The decreased organic matter can be attributed to restriction of inflow and thus decomposition of litter in the early stage after the restoration. The tree height growth rate ($m\;yr^{-1}$) of P. densiflora in Yuksimnyeong was the highest at 1.02, followed by Beolja at 0.75 and Ihwaryeong at 0.17. The height growth rate showed negative relationships with soil pH and cations, including Na and Ca concentrations and a positive relationship with available phosphate. The low growth rate in the Ihwaryeong site, in particular, might result from the poor nutrient availability due to high soil pH and the decrease in water absorption into the root due to high Na and Ca concentrations. The substantial reduction of organic matter after five years indicates that the need for soil improvement using chemical fertilizer and biochar.

• Journal of Korean Society of Rural Planning
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• v.26 no.1
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• pp.39-49
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• 2020

The study analyzed the frequency of simultaneous occurrence of keywords presented in a total of 805 papers published in domestic journals from 1995 to 2019 by social network analysis(SNS) method, and examined core keywords of each period(5 years), in order to understand the research trends of the rural residential environment. The main results are as follows. First, as a result of the analysis of centrality, 'Community', 'Tourism' and 'Comprehensive Rural Village Development Project' were the top 3 keywords. Second, examined by each period, the top keywords are 'Eco Friendly' in 2000~2004, 'Tourism' in 2005~2009 and 2010~2014, 'Community' in 2015~2019. Third, comparing the structural characteristics of core keywords 2nd, 3rd, and 4th period, a network centering on 'Tourism' was clearly formed in the 2nd period. 'Tourism' was divided into 'Community' and a movement to form a separate group appeared in the 3rd period. In the 4th period, 'Community' was found to form a network without direct connection with 'Tourism'. The results of this study suggest the trend change of viewpoint for the rural area in the domestic research on rural residential environment. It has been confirmed that while the research had been carried out with the viewpoint of rural area as a 'tourist attraction' or 'sightseeing spot' for the urban citizens until the mid-2010s, in the research of late 2010s the viewpoint has settled down as a 'residential space' or 'space for new economic activities' of a variety of rural residents.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.7
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• pp.920-926
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• 2019

In this study, we analyzed the erosion variation of beach area at Haeundae Beach after coastal improvement project using video monitoring system operated by the Coastal Erosion Monitoring (Ministry of Oceans and Fisheries). Haeundae Beach was well maintained and stabilized following large scale nourishment through coastal improvement project despite of seasonal fluctuations. However, multiple typhoons over the last two years caused beach stabilization patterns and seasonal fluctuations to lost equilibrium, resulting in rapid erosion. In particular, the sandy beach was eroded by typhoon Solic and Kongray in 2018 and failed to recover beach area in winter by seasonal fluctuations. And due to multiple typhoons in 2019, the beach area was reduced 9.5 % (12,607 ㎡) year-on-year. According to analyze the observed wave and beach area data in Haeundae, the tendency of erosion and sedimentation was influenced by seasonal incident wave direction for each section(west, center and east part). Therefore, to identify the causes of decreasing seasonal fluctuation characteristics and continuous erosion, hereafter, more precise monitoring of different factors are needed, such as the crest heights of submerged breakwater and its loss of function, and sand leakage to the outside around submerged breakwater.

• Journal of Korean Society of Rural Planning
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• v.19 no.3
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• pp.195-203
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• 2013

This study aimed to plan a distinctive apple theme park, thereby specializing the nationwide brand of Cheongsong apple. Detailed objectives included: to establish the best possible environments in Korea to taste and appreciate apple and enjoy the Cheongsong Apple Festival; to identify and foster natural, cultural and social resources in the clean environment of Cheongsong; to clusterize research and production infrastructures for strengthening local competitiveness; and to develop a hub for the vitalization of the region where visitors and locals can mutually prosper. The study was multi-phased. The first stage included basic surveys such as local status and environment analysis and similar case studies, and the second stage was to review the appropriateness of theme selection, develop basic principles and strategies for development goals and review and incorporate project details. And the third stage aimed to develop a comprehensive plan from spatial plans and program plans and suggest plans to vitalize the operation of the park. The dimension of the subject site was $180,150m^2$, which was divided into four areas, in consideration of the land use and the environmental characteristics of the resources, for developing a land use scheme. The four areas were named: the apple-theme cultual area; the agricultural culture experience area; the plaza for exchange and harmony; and the plaza for natural observation. This study has significance in that it can serve as a case to develop farm theme parks, and as a case of appropriate development of programs to identify amenity resources with a focus on the existing resources and in consideration of local characteristics.

• Journal of Ecology and Environment
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• v.39 no.1
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• pp.71-80
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• 2016

The main goal of this study is to develop a multi-metric fishway assessment model (M_m-FA) and evaluate the efficiency of fishway. The M_m-FA model has three major fishway components with nine metrics: structural characteristics, hydraulic/hydrologic features, and biological attributes. The model was developed for diagnosing and assessing fishway efficiency and tested to Juksan Weir at the Yeongsan River Watershed. Structural characteristics of fishway included slope of the fishway (M₁), ratios of fishway width to stream width (M₂), and the proportion of orifice clogging and orifice size (M₃). Hydraulic/hydrologic characteristics included depth of fishway entrance head (M₄), depth of exit tail (M₅), and current velocity of inner fishway (M₆). Biological characteristics included fish species ratio of inner fishway to upper-lower weir (M₇), fish length distribution (M₈), and the proportion of migratory fish species to the total number of species (M₉). Overall, the assessment of fishway efficiency showed the total score of the M_m-FA model was 25 in the Juksan Weir, indicating "good condition" by the criteria of the five-level classification system. The M_m-FA model may be used as a key tool for the assessment of fishway efficiency, especially on the 16 weirs constructed for the "Four Rivers Restoration Project" after a partial calibration of M_m-FA model.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.12
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• pp.1037-1044
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• 2014

In this study, we designed a drop test system considering lunar surface environment and tested landing gear of experimental lunar lander. The lunar lander would be landed at soil place for soft landing. When the lunar lander touches down, the acceleration of the lander is largely affected by mechanical characteristics of the lunar soil. Accordingly, a drop test using lunar soil is needed to verify the performance of the lunar landing gear. Because the lunar soil is not available generally, we developed a lunar simulant KAUMLS(Korea Aerospace University Mechanical Luna Simulant) based on mechanical properties of the lunar soil of NASA's LUNA PROJECT. In addition, drop tests on steel plate and dry sand are performed to evaluate impact characteristics by the surface environment.

• Journal of Internet of Things and Convergence
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• v.7 no.3
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• pp.39-46
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• 2021

This study aims to empirically analyze the effect of CRM on the management performance of senior club market type senior job business. The purpose of this study was to provide basic data for the economic income creation of senior club market type senior job project. The results of this study are as follows: First, as a result of verifying the difference in management performance according to sociodemographic characteristics, there was a difference in age, academic background, and monthly average income. Second, the contact service and communication of senior club market type senior job business had a positive effect on the management performance. Based on the results of this study, the following suggestions are made. First, the database(DB) should be constructed reflecting the personal characteristics of consumers and the big data and artificial intelligence analysis should be utilized. Second, education using Internet environment such as YouTube and ZOOM should be strengthened and communication management should be strengthened based on information collected through customer monitoring.

• Journal of Ecology and Environment
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• v.43 no.4
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• pp.461-468
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• 2019

Background: This study aimed to identify NO₃^--N sources using the stable isotope δ¹⁵N in Chydorus sphaericus (OF Müller), to investigate hydrological characteristics and nutrient states in artificial wetlands near the Nakdong River. Chydorus sphaericus is dominant in wetlands where aquatic plants are abundant, occurring in high density, and is sensitive to wetland water pollution, making it suitable for identification of NO₃^--N sources. Results: NO₃^--N sources for each wetland were strongly dependent on hydrological characteristics. Wetlands with sewage or rainfall/groundwater as their main sources had high levels of NO₃^--N, whereas wetlands with surface water as their main input had comparatively lower levels. Since wetlands with sewage and rainfall/groundwater as their main water sources were mostly detention ponds, their inputs from tributaries or the main river stream were limited and nutrients such as NO₃^--N easily become concentrated. Changes in NO₃^--N levels at each wetland were closely associated with δ¹⁵N of C. sphaericus. Interestingly, regression analysis also showed positive correlation between δ¹⁵N of C. sphaericus and NO₃^--N level. Conclusions: We conclude that the nitrate stable isotope (δ¹⁵N) of C. sphaericus can be used to elucidate the hydrological characteristics of riverine wetlands. This information is important for maintenance and conservation of artificial wetlands at the Nakdong River.

• Journal of Agricultural Extension & Community Development
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• v.20 no.2
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• pp.407-429
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• 2013

Although rural areas account for more than 80% of the total land area of South Korea, most of them are deteriorated and living environment is inconvenient. In addition, the migration of young generation to urban areas and ageing have reduced the population and caused not only cavitation phenomena of villages but also stagnant communities. As for one of the rural areas, the seat of Myeon Office located in Oesan-myeon, Buyeo-gun, Chungcheongnam-do, this study presented not a plan only for strengthening hub functions but the methodology of the complex development plan in consideration of the regional characteristics in the comprehensive improvement project in seat of Myeon Office. From the perspective of enhancing the function of the seat of Myeon Office, it is inevitable to establish plans based on hardware. However, empowerment of the residents in the targeted areas also works as an important factor. In other words, each project promoted by the plan will be mainly operated by the local residents. Therefore, it is necessary to establish a management system of this. The success or failure of the established plan is based on the accurate survey of the issues of the targeted areas and demand, and this depends on participation and positive response of the residents of the targeted areas. That is, the method as a 'local community network' is required in order to increase the effect of resident participation in the planning area.