• Journal of Environmental Impact Assessment
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• v.30 no.4
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• pp.237-246
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• 2021

The similarity of hourly PM₁₀ and PM_2.5 concentration profiles of the atmospheric monitoring stations in Gyeonggi-do was evaluated through the multilateral analysis between stations. The existing category for most stations in the regions shows relatively low Pearson correlation values of 0.68 and 0.7 for PM₁₀ and PM_2.5 on average respectively, and some monitoring stations revealed high relationships over 0.8 to other regions. Since the current regions are mainly categorized by cluster analysis based on the number of occurrence of high concentration events and geological factors, it is necessary to reclassify them by concentration characteristics for precise fine dust management. In accordance, multi-dimensional scaling being able to visualize could categorize the regions based on regional emission contribution rate and hourly fine dust concentration. As a result of the current analysis, PM₁₀ and PM_2.5 could be reclassified into five regions and fourregions, respectively.

• Particle and aerosol research
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• v.17 no.4
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• pp.91-106
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• 2021

Daily PM_2.5 was collected during summer period in 2020 in Gwangju to investigate its chemical and light absorption properties. In addition, real-time light absorption coefficients were observed using a dual-spot 7-wavelength aethalometer. During the study period, SO₄^2- was the most important contributor to PM_2.5, accounting for on average 33% (10-64%) of PM_2.5. The chemical form of SO₄^2- was appeared to be combination of 70% (NH₄)₂SO₄ and 30% NH₄HSO₄. Concentration-weighted trajectory (CWT) analysis indicated that SO₄^2- particles were dominated by local pollution, rather than regional transport from China. A combination of aethalometer-based and water-extracted brown carbon (BrC) absorption indicated that light absorption of BrC due to aerosol particles was 1.6 times higher than that due to water-soluble BrC, but the opposite result was found in absorption Ångström exponent (AAE) values. Lower AAE value by aerosol BrC particles was due to the light absorption of aerosol BrC by both water-soluble and insoluble organic aerosols. The BrC light absorption was also influenced by both primary sources (e.g., traffic and biomass burning emissions) and secondary organic aerosol formation. Finally the ATR-FTIR analysis confirmed the presence of NH₄⁺, C-H groups, SO₄^2-, and HSO₄^2-. The presence of HSO₄^2- supports the result of the estimated composition ratio of inorganic sulfate ((NH₄)₂SO₄) and bisulfate (NH₄HSO₄).

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.506-513
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• 2021

The durability and safety of reinforced concrete structures significantly depend on the reinforcement conditions, concrete cover thickness, cracks, and concrete strength. There are two ways to accurately determine the information on reinforcing bars embedded in concrete - the local destructive method and the non-destructive rebar detection test. In general, the non-destructive rebar detection tests, such as the electromagnetic wave radar method, electromagnetic induction method, and radiation method, are adopted to avoid damage to the structural elements. The moisture content and temperature of concrete affect the dielectric constant, which is the electrical property of concrete, and cause interference in the non-destructive rebar detection test results. Therefore, in this study, the effects of the electromagnetic wave radar method and electromagnetic induction method have been analyzed according to the temperature and surface moisture content of concrete. Due to the technological advancement and development of equipment, the average error rate was less than 5% in the specimens at 24℃, irrespective of their operating principles. Among the tested methods, the electromagnetic induction method showed very high accuracy. The electromagnetic wave radar method indicated a relatively small error rate in the dry state than in the wet state, and exhibited a relatively high error rate at high temperatures. It was confirmed that the error could be reduced by applying the electromagnetic wave radar method when the temperature of the probe was low and in a dry state, and by using the electromagnetic induction method when the probe was in a wet state or at a high temperature.

• Therapeutic Science for Rehabilitation
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• v.11 no.2
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• pp.77-91
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• 2022

Objective : This study aimed to assess the effects of occupation-based lifestyle intervention programs on older adults in the local community. Methods : Nine community-dwelling older individuals participated in this study using a one-group pre-post design. The occupation-based lifestyle intervention program consisted of 12 group sessions, and one individual session was conducted for seven weeks. Occupational balance, activity occupancy, activity participation, depression, health-related quality of life, and program satisfaction were assessed. Results : The average attendance rate of the nine participants was 10.11 (SD=1.36). Overall occupational balance (p=.012), activity participation status (p=.008), performance (p=.012), and satisfaction with activity participation (p=.008) were increased. Furthermore, the results showed changes in leisure time (p=.008) and rest time (p=.008). Finally, there were some improvements in the overall health-related quality of life (p=.034) and depression scores (p=.012). Conclusions : Occupation-based lifestyle intervention programs positively affected occupational balance, activity occupancy, activity participation, depression, and health-related quality of life in community-dwelling older adults. This research suggests promising benefits and feasibility of the program for community-dwelling older adults.

• Journal of Wetlands Research
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• v.24 no.1
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• pp.44-51
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• 2022

In this study, TOPSIS(Techniques for Order Performance by Similarity to Ieal Solution) was used to evaluate the installation points of water quality monitoring networks in 34 streams of the Nakdong River watershed. The Nakdong River System has been measuring water quality and flow in 195 local streams since 2011. In particular, the 34 key management points are areas with many pollutants and poor water quality, requiring continuous water quality management. For the selection of points requiring management, 10 indicators were selected for evaluation, and the selected indicators were standardized and weighted using the entropy method. As a result of weight calculation, the presence or absence of a nearby measuring network received the greatest weight, and the average water quality and presence of an industrial complex obtained the highest weight. The evaluated data are judged to be the research results necessary for the establishment of a new water quality measurement network in the Nakdong River system and continuous water quality management in tributaries.

• 지역과문화
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• v.7 no.4
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• pp.21-48
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• 2020

The purpose of this study is to analyze how the integrated heritage conservation actually affected the urban economy of historical cities. To this end, this study examined the trends and meanings of an integrated heritage conservation, and a relationship between sustainable urban development and integrated heritage conservation to find out connectivity with urban economy. Before an empirical analysis of domestic policy of integrated conservation of heritage, this study overlooked the system of the preservation and promotion of ancient cities, which can be called integrated heritage conservation system in Korea, and examined how the historic landscape improving project, which is being implemented as part of the policy of the preservation and promotion of ancient cities, actually affected the urban economy. This study empirically identified the impact of the project through a land price analysis of the region. This study focused on analyzing an impact of the project on a price of land in the proximity of subsidized land lot and analyzed the impact through Difference-In-Difference method. In particular, the project effect was analyzed only for the settlement zones among the preservation and promotion zones where the project was carried out, and as a result, it was confirmed that the average price of lands in the proximity of subsidized land increased more over the same period than in the areas where the project was not intensively implemented.

• Journal of the Korean Orthopaedic Association
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• v.55 no.4
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• pp.331-337
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• 2020

Purpose: The aim of this retrospective study was to define the prognostic factors for liposarcoma to aid in the selection of effective treatments. Materials and Methods: This study analyzed 41 cases out of 45 cases diagnosed with and treated for liposarcoma 2002 to 2015; 4 cases of well-differentiated liposarcoma were excluded. The effects of sex, age, site, stage, and histological classification on survival were analyzed retrospectively. For 28 cases diagnosed with myxoid liposarcoma, additional analysis was performed after the inclusion of round cell components. Results: The mean age at diagnosis was 52.05 years (range 25-82 years) and the average follow-up period was 63.7 months. The disease-free survival rate was 43.2%. Most factors, including sex and age, were not significantly associated with the survival rate. On the other hand, the stage (Musculoskeletal Tumor Society stage) was significantly associated with the survival rate. The survival rate of patients with myxoid liposarcoma was 69% and the local recurrence and metastasis results varied according to the presence of round cells. Conclusion: The stage of liposarcoma and the sex of the patient were found to be effective factors for prognosis. When planning the treatment for liposarcoma, the treatment outcome for liposarcoma differs according to several prognostic factors.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.15-22
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• 1993

Korean local collected strains of perilla were analyzed on their protein and amino-acid contents in the seed. The strains analyzed were 80 of which grown in the experimental field of Crop Experiment Station at Suwon in 1991. This experiment was performed to obtain the basic informations on the varietal differences of protein and amino-acid contents and further applied in the breeding project for quality improvement of perilla. The seed protein contents of 80 perilla varieties ranged from 17.9% to 24.6% and the average content was 24.6%. There were no differences in protein contents according to the maturity and 1,000 seed weight, but differed by the seed coat color showing 1.4% higher content in light gray than that of drak brown, which may suggest that the seed coat color could be used as a marker gene for breeding high protein varieties. While the total essential amino-acid contents of collected perilla ranged from 36.41% to 44.85%, the mean of 40.55%, the non-essential amino-acid contents was 47.23%～60.01% with the mean of 55.29%. Moreover, there was high positive correlation between the essential amino-acid contents and seed coat color. The essential amino-acids of perilla has an exceptionally high content of arginine, leucine, but methionine indeed being almost marginal. Of the essential amino-acids, lysine, methionine and valine were contained higher compared with the FAO recommendation level.

• Journal of Practical Agriculture & Fisheries Research
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• v.13 no.1
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• pp.173-183
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• 2011

Gabensis village is one of the biggest village In the Wampar Local Level Government area within the Huon Gulf District of Morobe Province with a population of around 3,000. The major staple food is banana which is well complemented by minor staples yam, cassava, Singapore/Chinese taro and sweet potato. Apart from gardening for own consumption, the villagers engage in selling of vegetables, garden staples, cocoa beans, coconuts, timber, chicken, fish and pig meat to supplement their livelihood. Livestock like pigs and chickens are also kept for meat and for commercial purpose. Bettlenut which was once one of the main cash crops has now been overtaken by cocoa due to a disease that had attacked almost the entire bettlenut tree population in the area. Even though the Wau-Bulolo highway cuts through the village and all have access to transport infrastructure, the majority of the population still encounter problems in communication due to poor telecommunication coverage. On average most people earn not more than K50 per week due to constrains in production and marketing among others. Gabensis village has the potential to develop a tourism industry given its natural attraction of Lake Wanam. Beside there is also the natural eel farming and the fish pond at the nearby Potsie village. These natural attractions pose huge tourism potential for the community. As part of government services delivery and development, education and health issues is very much important in the community however there is lack of infrastructural development and poor service delivery especially in the area of health. However, the responsibility is on the community to organize themselves to realize that potential. A well developed agro-ecotourism investments would have positive spillover effects to the community thus contributing towards improving the livelihoods of the many farming families.

• Journal of the Korean Society of Safety
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• v.38 no.2
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• pp.96-103
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• 2023

Generally, human stampedes and crowd collapses occur when people press against each other, causing falls that may result in death or injury. Particularly, crowd accidents have become increasingly common since the 1990s, with an average of 380 deaths annually. For instance, in Korea, a stampede occurred during the Itaewon Halloween festival on October 29, 2022, when several people crowded onto a narrow, downhill road, which was 45 meters long and between 3.2 and 4 meters wide. Precisely, this stampede was primarily due to the excessive number of people relative to the road size. Essentially, stampedes can occur anywhere and at any time, not just at events, but also in other places where large crowds gather. More specifically, the likelihood of accidents increases when the crowd density exceeds a turbulence threshold of 5-6 /m². Meanwhile, festivals and events, which have become more frequent and are promoted through social media, garner people from near and far to a specific location. Besides, as cities grow, the number of people gathering in one place increases. While stampedes are rare, their impact is significant, and the uncertainty associated with them is high. Currently, there is no scientific system to analyze the risk of stampedes due to crowd concentration. Consequently, to prevent such accidents, it is essential to prepare for crowd disasters that reflect social changes and regional characteristics. Hence, this study proposes using digital topographic maps and crowd-density risk simulations to develop a 3D model of the region. Specifically, the crowd density simulation allows for an analysis of the density of people walking along specific paths, which enables the prediction of danger areas and the risk of crowding. By using the simulation method in this study, it is anticipated that safety measures can be rationally established for specific situations, such as local festivals, and preparations may be made for crowd accidents in downtown areas.