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Evaluation of Runoff Prediction from a Coniferous Forest Watersheds and Runoff Estimation under Various Cover Degree Scenarios using GeoWEPP Watershed Model (GeoWEPP을 이용한 침엽수림 지역 유출특성 예측 및 다양한 식생 피도에 따른 유출량 평가)

  • Choi, Jaewan;Shin, Min Hwan;Cheon, Se Uk;Shin, Dongseok;Lee, Sung Jun;Moon, Sun Jung;Ryu, Ji Cheol;Lim, Kyoung Jae
    • Journal of Korean Society on Water Environment
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    • v.27 no.4
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    • pp.425-432
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    • 2011
  • To control non-point source pollution at a watershed scale, rainfall-runoff characteristics from forest watersheds should be investigated since the forest is the dominant land use in Korea. Long-term monitoring would be an ideal method. However, computer models have been utilized due to limitations in cost and labor in performing long-term monitoring at the watersheds. In this study, the Geo-spatial interface to the Water Erosion Prediction Project (GeoWEPP) model was evaluated for its runoff prediction from a coniferous forest dominant watersheds. The $R^2$ and the NSE for calibrated result comparisons were 0.77 and 0.63, validated result comparisons were 0.92, 0.89, respectively. These comparisons indicated that the GeoWEPP model can be used in evaluating rainfall-runoff characteristics. To estimate runoff changes from a coniferous forest watershed with various cover degree scenarios, ten cover degree scenarios (10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%) were run using the calibrated GeoWEPP model. It was found that runoff increases with decrease in cover degree. Runoff volume was the highest ($206,218.66m^3$) at 10% cover degree, whereas the lowest ($134,074.58m^3$) at 100% cover degree due to changes in evapotranspiration under various cover degrees at the forest. As shown in this study, GeoWEPP model could be efficiently used to investigate runoff characteristics from the coniferous forest watershed and effects of various cover degree scenarios on runoff generation.

The Leadership Core-Value of the Muaesabang(無碍四方, Intercommunication) (무애사방(無碍四方)의 리더십 핵심가치)

  • Ahn, Eun-Soo
    • The Journal of Korean Philosophical History
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    • no.23
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    • pp.67-97
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    • 2008
  • In this paper, I found the leadership core-value of the Sunbai(선배) a man of refined taste. I studied twelve Sunbai considered as a man of refined taste in this research. I focused on the aspect showing common worth among their various abilities and cultural contributions, a point of view of classifying them into one form called Sunbai a man of refined taste. As the core value is the basis of supporting the individual identity, so the leadership core-value is the source and philosophical base of displaying the leadership. Our Sunbai combining character and knowledge show common structure in their personal growth and showing the leadership. It is that they embodied the stage of cultivating themselves(修身, Self), considering the relation with others(齊家, Relation), leading the organization(治國, Team), and making efforts for and having influence on the community(平天下, Community) throughout their own life. I examined how to display the leadership in the four fields on a case by case basis and then constructed the leadership model of the Sunbai a man of refined taste by synthesizing them. As a result, I considered their leadership core-value as the intercommunication and named it 'Leadership of Muaesabang(無碍四方)'. Also, I confirmed that it is still very valuable in these days of aiming at the open society and the harmony of the diverse civilization.

Study on Estimation Method of Water Cycle Goal in Waterfront City (수변도시의 물순환 목표 산정 방안 연구)

  • Kim, Jae-Moon;Baek, Jong-Seok;Shin, Hyun-Suk;Park, Kyoung-Jae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.475-487
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    • 2020
  • The current water-management paradigm is changing from the expansion of reservoirs and facilities for simple outflows and non-point source management to the building of a sound water circulation system throughout the watershed. Based on this, water management for the watershed as a whole is establishing standards through local ordinances. The purpose of this study is to establish water cycle targets that are resilient to water management even after the development of cities in watersheds where water management is highly needed. This was done by referring to research and ordinances related to water circulation by local governments. A method is proposed based on a storage and infiltration method for rainfall. Through a comparison of percentiles, it was found that the water circulation target of a planned waterside city can be treated with 52% of total rainfall and 80% of rainfall of 17 mm per day. To quantitatively improve the quality results of these calculation procedures, it is estimated that the calculation of water cycle targets will be more reliable if other various variables such as the safety of low impact development factors or the selection of appropriate specifications are considered later.

Study on the Brittle Crack Arrest Property for 9% Ni Steel by Duplex ESSO test (Duplex ESSO 시험법에 의한 9% Ni강 취성 균열정지 특성 연구)

  • Kim, Young Kyun;Oh, Byung Taek;Yang, Young Chul;Yoon, Ihn soo;Kim, Jae Hoon
    • Journal of the Korean Institute of Gas
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    • v.24 no.6
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    • pp.47-54
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    • 2020
  • A brittle fracture is one of the source of structural damage and can bring a fatal accident. The inner shell of LNG storage tank should be designed and applied to construction by ensure that no brittle crack will occur under -162℃ condition. In point of view of fracture mechanics brittle fracture in the structure could be referred as crack initiation and crack arrest. It should be designed no crack initiation. However, in the unlikely event of a brittle fracture occurring, a back-up function of arresting the brittle crack should be included for the design. In this paper investigated the characteristics of 9% Ni steel thick plates of having a capability of arresting brittle cracks under the thickness of 33 mm, 37mm, 40 mm. First, charpy test has performed to evaluate the fundamental brittle impact fracture property of 9% Ni steel under the temperature of 24℃, -162℃ and -196℃. In addition, Duplex ESSO tests were also performed under -196℃ to evaluate the capability of crack arrest for 9% Ni steel. From the experiments results, it was confirmed that all the thickness of 9% Ni steel plates exhibits sufficient brittle crack arrest fracture toughness for the application of LNG storage tank as a inner shell.

Accuracy Evaluation of Open-air Compost Volume Calculation Using Unmanned Aerial Vehicle (무인항공기를 이용한 야적퇴비 적재량 산정 정확도 평가)

  • Kim, Heung-Min;Bak, Su-Ho;Yoon, Hong-Joo;Jang, Seon-Woong
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.3
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    • pp.541-550
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    • 2021
  • While open-air compost has value as a source of nutrients for crops in agricultural land, it acts as a pollution that adversely affects the environment during rainfall, and management is required. In this study, it was intended to analyze the accuracy of calculating open-air compost volume using fixed-wing UAV (unmanned aerial vehicle) capable of acquiring a wide range of images and automatic path flights and to identify the possibility of utilization. In order to evaluate the accuracy of calculating the three open-air compost volume, ground LiDAR surveys and precision surveys using a rotary UAV were performed. and compared with the open-air compost volume acquired through a fixed-wing UAV. As a result of comparing the calculation of open-air compost volume based on the ground LiDAR, the error rate of the rotary-wing was estimated to be ±5%, and the error rate of fixed-wing was -15 ~ -4%. one of three open-air compost volume calculated by fixed-wing was underestimated as about -15 %, but the deviation of the open-air compost volume was 2.9 m3, which was not significant. In addition, as a result of periodic monitoring of open-air compost using fixed-wing UAV, changes in the volume of open-air compost with time could be confirmed. These results suggested that efficient open-air compost monitoring and non-point pollutants in agricultural for a wide range using fixed-wing UAV is possible.

Research on Design Capacity Evaluation of Low Impact Development according to Design Criteria (저영향개발 시설 설계 기준에 따른 용량 평가 방법 연구)

  • Im, Jiyeol;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.24 no.1
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    • pp.59-67
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    • 2022
  • The interest in LID facilities is increasing worldwide for recovery of natural water cycle system to destroy by urbanization. However, problems are raised when installation of LID because comprehensive analysis about design capacity adequacy of LID facilities was not conducted completely. In this research, removal efficiency and design volume adequacy of LID facilities were analyzed based on rainfall monitoring data in four LID facilities(Vegetated Swale, Vegetative Filter Strip, Bio-Retention and Permeable Pavement). As a result, group of LID facility designed on WQV was shown higher flow(37%) and pollutants(TSS, BOD, TN and TP) removal efficiencies(20 ~ 37%) than group of LID facility designed on WQF. SA/CA graph was drawn for evaluation of design volume adequacy based on rainfall monitoring data. In this SA/CA graph, coefficient of determination show over 0.5 in all parameter, especially, Flow and TP were show over 0.95. And, 'SA/CA & L/CA' graph considering difference of structure mechanism in LID facility suggested in this research was confirmed that improved coefficient of determination in flow, TSS and TP than SA/CA graph. According to this research results, feasibility of applying 'SA/CA & L/CA' graph for evaluation of design volume adequacy in LID facility, and it is necessary to follow up research for generalization and normalization.

Heavy Metals in Road Deposited Sediments and Control of Them in Urban Areas: A Review (문헌고찰에 의한 도시 지역 도로퇴적물의 중금속 특성 및 적정 관리방안)

  • Kim, Do Gun
    • Land and Housing Review
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    • v.13 no.3
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    • pp.125-140
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    • 2022
  • Road Deposited Sediment (RDS) is the solids formed from the wear of road, wear of vehicles, exhausts, and the input of the emissions from various sources out of the roads. RDS is seriously polluted by organic matter, nutrients, and metals. RDS plays an important role as the sink and the transport medium of the associated pollutants because RDS can be carried to the adjacent water system via stormwater runoff. In this regard, the heavy metals in RDS were investigated based on the publications. The contents of the metals in RDS were highly variable. The concentration of Cr, Ni, Cu, Fe, Zn, As, Cd, and Pb in urban RDS in various regions was in a range of 3.16-3,410, 1.15-1,382, 20.2-9,069, 2,980-124,853, 81-2,550, 2.3-214, 0.19-21.3, and 15.21-1,125 mg/kg, respectively. The anthropogenic enrichment of the metals in RDS was confirmed by the high concentration of Cu, Zn, Cd, and Pb. The contents of the metals were higher in industrial and traffic areas than in residential areas, while they were generally increased with decreasing particle size. It is believed that this study's results would contribute to quantifying the metals' load via RDS and establishing control strategies.

Characteristics of PAHs Concentration in Soil Contamination Concerned Area of Gwangju (광주지역 토양오염우려지역의 PAHs 농도 특성 연구)

  • Yoon, Sang Hoon;Lee, Woo Jin;Lim, Min Hwa;Jeong, Yeon Jae;Park, Mi Ae;Jeon, Hong Dae;Park, Byoung Hoon;Seo, Gwang Yeob;Bae, Seok Jin;Park, Jeong Hun
    • Journal of Soil and Groundwater Environment
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    • v.27 no.2
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    • pp.50-60
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    • 2022
  • The concentration levels and distribution characteristics of 16 polycyclic aromatic hydrocarbons (PAHs) were investigated and evaluated for total 100 soil samples as a part of the survey on soil contamination in Gwangju. The results (median and range) of T-PAHs (sum of 16 PAH concentrations), C-PAHs (sum of carcinogenic PAH concentrations) and T-TEQs (sum of 16 TEQ concentrations) were 20.8 (7.6~1158.1), 2.2 (N.D~509.6), and 0.3 (N.D~424.6) ㎍/kg, respectively. There was a positive correlation between C-PAHs/T-PAHs and T-TEQs/T-PAHs except one point where the concentration of benzo(a)pyrene was high. The ratios of the C-PAHs/T-PAHs were 31.7% for low molecular weight-PAHs and 68.3% for high molecular weight-PAHs, suggesting that PAHs generation mainly arose from combustion sources. The ratio of isomers of individual PAHs, Phe/Ant, Flu/Pyr, Ant/(Ant+Phe), Flu/(Flu+Pyr), and BaA/(BaA+Chr), also confirmed the predominance of PAHs from combustion activities. Statistical tracing of the source of PAHs through principal component analysis indicated that the main sources of combustion were automobile fuel and coal. The overall results of this study suggested HMW-PAHs, T-PAHs, C-PAHs and T-TEQs should be separately evaluated to better assess the toxicity and environmental behavior of individual PAHs.

Exploring the Potential of Podcasts in Flower Design Industry (플라워디자인 산업 활성화를 위한 팟캐스트 콘텐츠의 가능성 연구)

  • Yang, Dongbok
    • Journal of the Korean Society of Floral Art and Design
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    • no.44
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    • pp.75-100
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    • 2021
  • The purpose of this study is to explore ways in which the flower design industry can utilize podcasts that are rapidly growing in recent years. I selected foreign flower podcasts that are ranked on the global podcast chart, and examined the genre, content, components, show hosts and etc. By analyzing the characteristics of the podcast, the type of communication between the host and the audience, the audience interaction, the industry connection, and the media expansion strategy, I tried to derive the possibility of the flower podcast in Korea. As a result of analyzing foreign flower podcasts, podcasters built listener communities based on their rich experience and knowledge through podcasts and used them for education and marketing. They acted as leaders in the industry or led public opinion such as the sustainable flower industry. Podcast shows were repurposed as various content and used to spread flower design culture. In Korea, flower podcasts can be the basis for the formation of a community related to the flower design industry. Flower design experts can use podcasts as a source asset for various content. Listeners within the industry can get hands-on knowledge about the business from flower podcasts. The popular flower podcast will contribute to the vitalization of flower design culture and industry. Flower podcasts can be a starting point to actively cope with the era of personal media.

A Study on the Current Status and Characteristics of Fine Dust Generation in Construction Waste Intermediate Treatment Plants and Neighboring Areas (건설폐기물 중간처리 사업장과 인근 지역의 미세먼지 발생 현황 및 특성에 관한 연구)

  • Jang, Kyong-Pil;Song, Tae-Hyeob;Kim, Byung-Yun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.9 no.4
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    • pp.405-412
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    • 2021
  • The objective of this study is to investigate the environmental impact of fine dust generated at the construction waste intermediate treatment plants, and to propose engineering data and measures to suppress the generation of fine dust to cope with the expected strengthened environmental regulations of the government. The following study conclusions are drawn. 1) T he maximum concentration of fine dust in the workplace was measured as 160㎍/m3 from the crushing operation followed by the point of waste unloading, where focused suppression plan of the fine dust generation is needed in the future. 2) Fine dust concentrations of 113㎍/m3 in wet road conditions and 50㎍/m3 in dry conditions were measured, indicating that fine dust could be reduced by 50% with watering alone. 3) The effect of distancing from the dust source was studied. PM10 during operation of the workplace was measured as about 25㎍/m3 higher than those of the neighboring areas. Whereas there was no significant difference in case of PM2.5 between workplace and neighboring areas. 4) The measurement results of the heavy metal contents showed that these metals did not affect neighboring areas.