• Title/Summary/Keyword: 중앙분리대

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Use of Visible Storage for Display and Conservation Treatment of a Large-sized Jar Coffin (대형 옹관의 보존처리 과정과 이를 활용한 개방형 수장고의 운용)

  • Kwak, Eungyung;Lee, Hyejin;Yu, Sohyun
    • Conservation Science in Museum
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    • v.19
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    • pp.41-52
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    • 2018
  • This paper describes the restoration and display of a large jar coffin at the Naju National Museum. Excavated from Tomb No. 3 at Bokam-ri, Naju, the large jar is 194 cm in height and its rim diameter is 108 cm. The jar had been broken into approximately forty fragments prior to its restoration, and a supporting structure was installed to ensure the safety of the relic during the restoration process. The restoration was conducted inside a visible storage for large jar coffins for approximately three weeks from February 5 to February 27, 2018. Over two weeks during this period, the restoration efforts inside the storage were visible to the public in the permanent exhibition space so that visitors could observe the process in person. This was planned to help visitors understand and arouse their interest in large-sized relics such as jar coffins and the restoration process. This study also investigates the practices of overseas institutions in order to suggest plans for raising public awareness of conservation treatment at conservation science centers.

Operating result of Hydroxyapatite Crystallization-Filtration (HCF) process and characterization of its sludge for wastewater effluent (하수 인 고도처리를 위한 인 결정여과공정 운전결과 및 부산슬러지 특성 검토)

  • Chang, Hyang-Youn;Kim, Weon-Jae
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.401-401
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    • 2022
  • 우리나라 대규모 하수처리장에 상용화되어있는 응집공정의 운영상 난점을 극복하고자 대체공정으로 고안된 인 결정여과공정(HCF, Hydroxyapatite Crystallization-Filtration process)의 pilot plant를 구축하고 부산슬러지의 자원화를 위해 그 특성을 검토하였다. 기존의 hydroxyapatite(HAP) 결정화공정 내 탈탄산(decarbonation) 단계를 생략하는 HCF공정의 경우에 고농도의 Ca2+ 주입과 처리수내 탄산염으로 인해 HAP을 포함하는 석회계 슬러지가 발생하는데, 이는 산성화된 토양의 개량제(중화제)로 널리 사용될 수 있다. 본 연구를 위해 경기도 I하수처리장 2차침전지 후단에 구축된 처리용량 27.1 - 135.6 m3/day HCF pilot plant의 전처리 조건은 pH 10.0 - 11.0, Ca2+ 농도 80 mg/L이었다. 결정여과조는 선속도 1.0 - 5.0 m/hr, 상향류로 운전되며, 여재는 2.0 - 3.0 mm의 석회석 모래를 충전하였다. 역세척은 중앙에 Air lifting pipe를 설치하여 역세척수가 처리수와 분리배출되도록 설계하였고, 침전시켜 역세척 슬러지를 회수하였다. 처리수의 평균 T-P, PO4-P 및 SS는 각각 0.05, 0.04, 1.1 mg/L으로 모든 항목에서 방류수 수질기준 이하로 안정적으로 유출되었다. 회수된 HCF 슬러지는 SEM-EDX, XRD, FT-IR을 활용하여 그 특성을 분석하였다. SEM-EDX로 분석된 슬러지의 원자분율은 CaCO3 또는 HAP으로 추측되었다. 또한, XRD spectrum 분석결과, 슬러지의 주요 구성성분은 calcite, HAP, phosphoric acid(H3PO4) 및 brusite로 나타났다. FT-IR 분석결과, 슬러지는 대부분 인산염 및 탄산염의 무기물로 구성되어 있으며, 유입수의 인 농도가 높을수록 슬러지 내 HAP의 함량이 calcite보다 높은 것으로 나타났다. 고농도의 Ca2+을 주입하여 탈탄산단계를 생략한 HCF의 부산슬러지는 HAP 이외에도 CaCO3와 칼슘-인 화합물로 구성되어 있는 것으로 나타났다. 하수 인 고도처리를 위한 HCF공정의 하수처리시설 인 고도처리 적용이 검증되었으며, 부산슬러지를 산성화된 토양의 개량제(중화제) 또는 비료로서의 재활용 및 자원화 가능성이 시사되었다.

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A Study on Machine Learning-Based Estimation of Roadkill Incidents and Exploration of Influencing Factors (기계학습 기반의 로드킬 발생 예측과 영향 요인 탐색에 대한 연구)

  • Sojin Heo;Jeeyoung Kim
    • Journal of Environmental Impact Assessment
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    • v.33 no.2
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    • pp.74-83
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    • 2024
  • This study aims to estimate roadkill occurrences and investigate influential factors in Chungcheongnam-do, contributing to the establishment of roadkill prevention measures. By comprehensively considering weather, road, and environmental information, machine learning was utilized to estimate roadkill incidents and analyze the importance of each variable, deriving primary influencing factors. The Gradient Boosting Machine (GBM) exhibited the best performance, achieving an accuracy of 92.0%, a recall of 84.6%, an F1-score of 89.2%, and an AUC of 0.907. The key factors affecting roadkill included average local atmospheric pressure (hPa), average ground temperature (℃), month, average dew point temperature (℃), presence of median barriers, and average wind speed (m/s). These findings are anticipated to contribute to roadkill prevention strategies and enhance traffic safety, playing a crucial role in maintaining a balance between ecosystems and road development.

Runoff Analysis for Weak Rainfall Event in Urban Area Using High-ResolutionSatellite Imagery (고해상도 위성영상을 이용한 도시유역의 소강우 유출해석)

  • Kim, Jin-Young;An, Kyoung-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.6
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    • pp.439-446
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    • 2011
  • In this research, enhanced land-cover classification methods using high-resolution satellite image (HRSI) and GIS in terms of practicality and accuracy was proposed. It aims for understanding non-point pollutant origin/loading, assessment the efficiency of rainfall storage/infiltration facilities and sounds water-environment management. The result of applying enhanced land-cover classification methods to the urban region verifies that roof and road area are including various vegetations such as roof garden, flower bed in the median strip and street tree. This accounts for 3% of total study area, and more importantly it was counted as impervious area by GIS alone or conventional indoor work. The feasibility of the method was assessed by applying to rainfall-runoff analysis for three weak rainfall in the range of 7.1-10.5 mm events in 2000, Chiba, Japan. A good agreement between simulated and observed runoff hydrograph was obtained. In comparison, the hydrograph simulated with land-use parameters by the detailed land-use information of 10m grid had an error between 31%~71%, while enhanced method showed 4% to 29%, and showed the improvement particularly for reproducing observed peak and recession flow rate of hydrograph in weak rainfall condition.

The recognition prioritization of road environment for supporting autonomous vehicle (자율주행차량의 도로환경 인식기술 지원을 위한 우선순위 선정 방안)

  • Park, Jaehong;Yun, Duk Geun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.595-601
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    • 2018
  • The era of autonomous vehicles, which drive themselves and in whose operation the driver does not intervene, is fast approaching. The safety of autonomous vehicles can be guaranteed only if they recognize the road infrastructure. However, the road infrastructure consists of road safety facilities, traffic operation systems, and cross-sectional concerns, which include a variety of components, such as types, shapes, and sizes. Therefore, it is necessary to prioritize the road information. This study was conducted to select the priority with which the road infrastructure attributes should be acquired using the AHP (Analytical Hierarchy Process) method. The road infrastructure attributes were categorized into 2 levels, levels 1 and 2, which consisted of 3 and 26 types of attributes, respectively. As a result of the AHP analysis, it was found that the highest priorities of the road infrastructure are the road safety facilities, traffic operation systems and cross sectional concerns. Also, in level-2, the priorities of the safety barriers (road safety facilities), traffic signals (traffic operation systems), and the median (cross sectional) are the highest. Also, this study provides application examples of road infrastructure extraction with the Point Cloud. The results are expected to support the recognition of technology for autonomous vehicles.

Division of Homogeneous Road Sections for National Highway by Genetic Algorithms (유전자 알고리즘을 적용한 국도의 동질성 구간 분할)

  • Oh, Ju-Sam;Lim, Sung-Han;Cho, Yoon-Ho
    • International Journal of Highway Engineering
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    • v.7 no.4 s.26
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    • pp.41-47
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    • 2005
  • Traffic data such as traffic volume, speed, and vehicle Class are very important basic data for the plan and design of highway. Based on traffic data, the future service level of a specific highway and geometry of newly constructed or expended road is predicted and determined. The Ministry of Construction & Transportation has simultaneously surveyed coverage count and permanent count at highways since 1985. Traffic volume survey sections were determined at jointed nodes of highways and jointed nodes of highways and other roads such as freeway and local highway. Volume survey was performed at these sections. The premise to decide these sections is assumed that links between jointed nodes of main highways exhibit similar traffic characteristics. Recently, due to the change of highway geometries such as construction of detour road and installations of traffic facilities such as installation of media, traffic characteristics of the existing traffic volume survey sections was changed. To reflect these changes, traffic characteristics at homogeneous road sections was widely evaluated and analyzed. Using Genetic Algorithms, a model was developed for the evaluation of traffic characteristics at homogeneous road sections. Traffic volume survey sections were then determined through the application of the developed model for current traffic system.

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An Overview on the Physicochemical Properties and Photocatalytic Pollutant Removal Performances of TiO2-incorporated Cementitious Composites (TiO2 혼입 시멘트 복합체의 물리·화학적 특성 및 광촉매 반응을 이용한 오염물 제거 성능에 대한 개요)

  • Seo, J.H.;Yoon, H.N.;Kim, S.H.;Bae, S.J.;Jang, D.I.;Kil, T.G.;Park, S.M.;Lee, H.K.
    • Composites Research
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    • v.33 no.2
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    • pp.68-75
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    • 2020
  • Recently, the use of TiO2 as a phtocatalyst has been diversely investigated due to its excellent durability performance and high photocatalytic reaction efficiency. Active researches have particularly focused on the development of TiO2-incorporated cementitious composites in order to remove the atmospheric pollutants. Furthermore, the potential utilization of TiO2-incorporated cementitious composites as road accessories such as tunnels, road median separators and soundproof walls in the form of tiles, blocks and structural components has been widely examined. In this regard, a thorough understanding on the material characteristics of TiO2-incorporated cementitious composites should be preceded. The present overview article, therefore, revisits previous studies of TiO2-incorporated cementitious composites and summarizes their various physicochemical properties and atmospheric pollutants removal performance.

A Road Feature Extraction and Obstacle Localization Based on Stereo Vision (스테레오 비전 기반의 도로 특징 정보 추출 및 장애 물체 검출)

  • Lee, Chung-Hee;Lim, Young-Chul;Kwon, Soon;Lee, Jong-Hun
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.46 no.6
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    • pp.28-37
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    • 2009
  • In this paper, we propose an obstacle localization method using a road feature based on a V-disparity map binarized by a maximum frequency value. In a conventional method, the detection performance is severely affected by the size, number and type of obstacles. It's especially difficult to extract a large obstacle or a continuous obstacle like a median strip. So we use a road feature as a new decision standard to localize obstacles irrespective of external environments. A road feature is proper to be a new decision standard because it keeps its rough feature very well in V-disparity under environments where many obstacles exist. And first of all, we create a binary V-disparity map using a maximum frequency value to extract a road feature easily. And then we compare the binary V-disparity map with a median value to remove noises. Finally, we use a linear interpolation for rows which have no value. Comparing this road feature with each column value in disparity map, we can localize obstacles robustly. We also propose a post-processing technique to remove noises made in obstacle localization stage. The results in real road tests show that the proposed algorithm has a better performance than a conventional method.

Developing an Accident Model for Rural Signalized Intersections Using a Random Parameter Negative Binomial Method (RPNB모형을 이용한 지방부 신호교차로 교통사고 모형개발)

  • PARK, Min Ho;LEE, Dongmin
    • Journal of Korean Society of Transportation
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    • v.33 no.6
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    • pp.554-563
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    • 2015
  • This study dealt with developing an accident model for rural signalized intersections with random parameter negative binomial method. The limitation of previous count models(especially, Poisson/Negative Binomial model) is not to explain the integrated variations in terms of time and the distinctive characters a specific point/segment has. This drawback of the traditional count models results in the underestimation of the standard error(t-value inflation) of the derived coefficient and finally affects the low-reliability of the whole model. To solve this problem, this study improves the limitation of traditional count models by suggesting the use of random parameter which takes account of heterogeneity of each point/segment. Through the analyses, it was found that the increase of traffic flow and pedestrian facilities on minor streets had positive effects on the increase of traffic accidents. Left turning lanes and median on major streets reduced the number of accidents. The analysis results show that the random parameter modeling is an effective method for investigating the influence on traffic accident from road geometries. However, this study could not analyze the effects of sequential changes of driving conditions including geometries and safety facilities.

A Meta Analysis of the Effects of Road Safety Facilities on Accident Reduction: Focusing on Signalized Intersection (도로안전시설의 사고감소효과 메타분석 : 신호교차로를 대상으로)

  • CHOI, Ji Hye;LIM, Joon Beom;LEE, Soo Beom
    • Journal of Korean Society of Transportation
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    • v.34 no.4
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    • pp.291-303
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    • 2016
  • The number of traffic accidents at intersections has been increased over the past decade, and in 2014, accounted for 44% of the total traffic accidents. In addition, since most of road accident black spots include signalized intersections, the improvement of safety on signalized intersection is top priority for national road safety program in Korea. For the decision of most effective action plan for the safety of signalized intersection, this study conducted meta-analyses to assess the effects of various road safety facilities at signalized intersection on traffic accidents. We selected 19 articles regarding the prediction of traffic accidents at signalized intersection and calculated 34 individual effect sizes on 8 variables included in the articles. The results found that there was a statistically significant negative relationship between the occurrence of traffic accident and the presence of all of road safety facilities except an exclusive left turn bay. It shows that most of the road safety facilities could prevent traffic accidents, and intersection channelization has the most effective on the reduction of traffic accidents followed by left-turn acceleration lane, lightning, crosswalk, exclusive right-turn lane and median barrier.