• 제목/요약/키워드: Drainage Tool

검색결과 77건 처리시간 0.027초

다져진 도로기초 재료의 불포화투수특성 평가 (I) : 실내실험 (Evaluating Unsaturated Hydraulic Properties of Compacted Geomaterials in Road Foundations (I) : Laboratory Test)

  • 박성완;성열정
    • 대한토목학회논문집
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    • 제31권1D호
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    • pp.73-82
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    • 2011
  • 일반적으로 다져진 도로기초 지반재료의 장기적인 강도나 배수 거동 평가시 불포화상태를 고려하지 않고 있다. 그래서 보조기층과 노상토와 같은 도로하부 기초에서의 불포화상태와 이력현상을 고려하는 것은 현실적이다. 따라서 보다 정량적인 불포화 지반의 평가를 위하여 흡수력과 함수특성을 평가하기 위한 적절한 장비, 재료모델, 그리고 투수계수에 대한 평가가 필요하다. 본 논문에서는 이러한 거동을 알아보기 위해서는 흙-수분 관계인 재료의 함수특성곡선 측정 자료를 통하여 불포화 투수계수를 추정하고 이를 통하여 국내 대표적인 입상재료에 대한 불포화상태에서의 수분의 이동에 대한 관찰 및 분석을 수행하였다.

도시 소유역 배수펌프장 운영개선 방안 연구 (1) - GIS 기반 수문모형에 의한 홍수유출수문곡선의 재현 (Operational Improvement of Small Urban Storm Water Pumping Station (1) - Simulation of Flood Hydrograph using GIS-based Hydrologic Model)

  • 길경익;한종옥;김구현
    • 한국물환경학회지
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    • 제21권6호
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    • pp.682-686
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    • 2005
  • Recently some urban areas have been flooded due to heavy storm rainfalls. Though major causes of these floodings may be attributed to localized heavy rainfalls, other factors are related to urban flooding including deficiency of storm sewer network capacity, change of surface runoff due to covered open channels, and operational problems of storm drainage pump stations. In this study, hydrologic and hydraulic analysis of Sutak basin in Guri city were carried out to evaluate flooding problems occurred during the heavy storm in July, 2001. ArcView, a world most widely used GIS tool, was used to extract required data for the hydrologic analysis including basin characteristics data, concentration times, channel routing data, land use data, soil distribution data and SCS runoff curve number generation from digital maps. HEC-HMS, a GIS-based runoff simulation model, was successfully used to simulate the flood inflow hydrograph to Sutak pumping station.

Understanding Wet-End Polymer Performance through Visualization of Macromolecular Events by Transmission Electron Microscopy

  • Nanko, Hiroki;Mcneal, Michelyn;Pan, Shaobo
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.1
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    • pp.1-18
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    • 2006
  • A novel transmission electron microscopy technique for the visualization of polymers adsorbed on secondary fines has been developed. This technique has been utilized in observing the adsorption behavior of various wet-end additives. The technique is sensitive enough not only to allow differentiation between linear and branched polymers, but also to observe differences in the adsorption behavior and conformational characteristics of particular polymeric derivatives. Conformational changes of a cationic polyacrylamide (CPAM) were examined in response to variations in wet-end conditions, such as mixing time and system conductivity. The molecular conformations of cationic starch and cationic guar gum were also examined by this technique. The technique has been employed to observe the effects of silica microparticles on the conformational characteristics of CPAM (drainage/retention aid) pre-adsorbed on secondary fines. The transmission electron microscopy method is a viable tool for investigating the macromolecular events that make up a large part of wet end chemistry in papermaking.

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LANDFORM 분류를 위한 수치기복모형의 적용 (The application of a digital relief model to landform classification)

  • 양인태;김동문;유영걸;천기선
    • 산업기술연구
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    • 제19권
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    • pp.155-162
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    • 1999
  • In the last few years the automatic classification of morpholgical landforms using GSIS and DEM was investigated. Particular emphasis has been put on the morphological point attribute approaches and the extraction of drainage basin variables from digital elevation models. The automated derivation of landforms has become a neccessity for quantitative analysis in geomorphology. Furthermore, the application of GSIS technologies has become an important tool for data management and numerical data analysis for purpose of geomorphological mapping. A process developed by Dikau et al, which automates Hanmond's manual process, was applied to the pyoung chang of the kangwon. Although it produced a classification that has good resemblance to the landforms in the area, it had some problems. For example, it produced a progressive zonation when landform changes from plains to mountains, it does not distinguish open valleys from a plains mountain interface, and it was affected by micro relief. Although automating existing quantitative manual processes is an important step in the evolution automation, definition may need to be calibrated since the attributes are oftem measured differently. A new process is presented that partly solves these problems.

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화천 지역의 수문분석을 위한 SWAT 모형의 적용성 평가 (Evaluation of SWAT Model for Hydrological Analysis of Hwa-Cheon Watershed)

  • 김기철;김종건;박윤식;허성구;유동선;김기성;최중대;임경재
    • 한국관개배수논문집
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    • 제14권2호
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    • pp.207-213
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    • 2007
  • For sustainable development at a watershed, environment friendly site-specific management practices need to be developed and implemented. The soil and Water Assessment Tool(SWAT)model has been world-wide used to estimate stream flow, sediment, and nonpoint source pollutant loads, and effects on water quality of different management practices. In this study, the SWAT model was used to estimate the flow resources at Hwacheon areas using Digital Elevation Model(DEM),Land use, precipitation ,wind ,maximum and minimum temperature, solar radiation, humidity of watershed The R2 value and EI value for the comparison of SWAT estimated flow and measured flow were 0.87 and 0.67 respectively for calibration period, and the R2 value and E1 value for validation were 0.75 and 0.67 respectively. The comparison results show what the SWAT model is applicable to simulate hydrology behaviors at this study watershed.

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연약지반 장기 침하량 예측기법의 신뢰성 평가 (Reliability of Ultimate Settlement Prediction Methods)

  • 우철웅;장병욱;송창섭
    • 한국농공학회지
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    • 제38권6호
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    • pp.35-41
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    • 1996
  • The theory of consolidation has been achieved remarkable development in terms of theory such as finite consolidation theory, two dimensional Rendulic consolidation theory. Though those theories are well defined, the analysis is by no means straightforward, because associated properties are very difficult to determine in the laboratory, Therefore Terzaghi's one dimensional consolidation theory and Barron's cylindrical consolidation theory are still widely used in engineering practice. The theoretical shortcomings of those consolidation theories and uncertainties of associated properties make inevitably some discrepancy between theoretical and field settlements. Field settlement measurement by settlement plate is, therefore, widely used to overcome the discrepancy. Ultimate settlement is one of the most important factor of embankment construction on soft soils. Nowadays the ultimate settlement prediction methods using field settlement data are widely accepted as a helpful tool for field settlement analysis of embankment construction on soft soils. Among the various methods of ultimate settlement prediction, hyperbolic method and Asaoka's method are most commonly used because of their simplicity and ability to give a reasonable estimate of consolidation settlement. In this paper, the reliability of hyperbolic method and Asaoka's method has been examined using analytical methods. It is shown that both hyperbolic method and Asaoka's method are significantly affected by the direction of drainage.

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간극비를 고려한 흙-수분특성 방정식의 적용성 평가 (Dynamic Deformation Characteristics of Sands Under Various Drainage Conditions)

  • 임성윤;송창섭
    • 한국지반공학회논문집
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    • 제23권11호
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    • pp.39-48
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    • 2007
  • 지금도 불포화토의 특성곡선에 대한 연구는 계속 진행되고 있지만, 지금까지 발표된 특성곡선은 흙의 한가지 상태나 특성을 나타내도록 유도되어 광범위한 적용이 어려운 것은 사실이다. 따라서, 흙의 상태를 범용적으로 나타낼 수 있는 특성곡선을 개발하기 위해서는 현재까지 발표된 특성곡선의 적용성을 평가하여 문제점을 파악하는 것이 필요하다. 따라서 본 연구에서는 화강풍화토를 대상으로 함수특성곡선실험을 실시한 결과를 바탕으로 간극비에 따른 흙-수분 특성곡선 방정식을 분석하여 간극비에 따른 포화도를 예측하였으며 기존에 제안된 특성식에 대하여 적용성을 검증하였다.

울진 남대천 유역의 수계분석을 통한 단층 규명 사례 연구 (Case Study of Fault Based on Drainage System Analysis in the Namdae Stream, Uljin Area)

  • 한종규;최성자
    • 자원환경지질
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    • 제44권5호
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    • pp.399-412
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    • 2011
  • 지형정보가 전산화됨으로서 수치표고모델 및 위성영상사진 등이 지질조사에 활용되고 있다. 이 연구에서는 남대천 유역의 하천 수계 천이점을 추출하여 단층운동과의 연관성을 규명하고자 하였다. 경상북도 울진군에 위치하고 있는 남대천 유역은 S1, S2, S3 등 세 개의 소유역으로 구분되며, 수치표고모델로 추출된 천이점들은 거의 모두 소유역의 중류 및 중상류에 분포하고 있다. S1 구역에서는 하각률과 관련 있는 지형경사도 Ks와 하천 수계의 요형도 값이 S2 나 S3 보다 높은 값을 보이고 있다. 이는 삭박작용이 활발하여 하각률이 높은 것에 기인되는 것으로 암상 차에 의한 것보다는 다수의 단층에 의한 것으로 해석된다. 하위지류를 포함한 남대천 유역의 천이점은 모두 77개이며, 이 중 주요 수계 S1, S2, S3에 발달하고 있는 천이점은 24개소이다. 77개소 중 이중 단층과 일치하고 있는 천이점은 27개소 (38%)이며, 주요 수계 상에서 단층과 일치되는 천이점은 13개 지점 (54%)이다. 그러므로 주요 수계와 단층과는 밀접한 관계가 있음을 알 수 있다. 즉, 조사지역의 상대 경사도 값 Ks의 평균은 38.8이다. 그러나 두천단층과 삼당단층이 중첩되는 부분에서는 해발고도를 고려하더라고, 상대적 경사도 $K_s$은 42.99~43.39로 다른 전이점보다 매우 높은 값을 보이므로, 천이점 형성은 단층과 유관한 지형변위임을 지시한다. 또한 천이점의 분포와 지질 경계부를 비교해볼 때, 천이점은 암상 경계부와도 무관하게 발달하고 있으나, 단층분포와 연관성이 있음을 알 수 있다. 결론적으로, 수계의 천 이점 발달은 단층 운동에 의하여 형성될 수 있는 지형변위로 판단된다. 수계 분석을 통해 천이점이 단층에 의한 지형 변위로 볼 수 있으며, 제 4기 단층을 규명하거나 단층 연장을 규명할 수 있는 수단으로 활용 될 수 있다.

Seasonal color change of the oxyhydrous precipitates in the Taebaek coal mine drainage, south Korea, and implications for mineralogical and geochemical controls

  • Kim, J. J.;C. O. Choo;Kim, S. J.;K. Tazaki
    • 한국광물학회:학술대회논문집
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    • 한국광물학회.한국암석학회 2001년도 공동학술발표회 논문집
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    • pp.38-39
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    • 2001
  • The seasonal changes in pH, Fe, Al and SO$_4$$\^$2-/ contents of acid drainage released from coal mine dumps play a major role in precipitation of metal hydroxides in the Taebaek coal field area, southeastern Korea. Precipitates in the creeks underwent a cycle of the color change showing white, reddish brown and brownish yellow, which depends on geochemical factors of the creek waters. White precipitates consist of Al-sulfate (basaluminite and hydrobasaluminite) and reddish brown ones are composed of ferrihydrite and brownish yellow ones are of schwertmannite. Goethite coprecipitates with ferrihydrite and schwertmannite. Ferrihydrite formed at higher values than pH 5.3 and schwertmannite precipitated below pH 4.3, and goethite formed at the intermediate pH range between the two minerals. With the pH being increased from acid to intermediate regions, Fe is present both as schwertmannite and goethite. From the present observation, the most favorable pH that basauluminte can precipitate is in the range of pH 4.45-5.95. SEM examination of precipitates at stream bottom shows that they basically consist of agglomerates of spheroid and rod-shape bacteria. Bacteria species are remarkably different among bottom precipitates and, to a less extent, there are slightly different chemical compositions even within the same bacteria. The speciation and calculation of the mineral saturation index were made using MINTEQA2. In waters associated with yellowish brown precipitates mainly composed of schwertmannite, So$_4$ species is mostly free So$_4$$\^$2-/ ion with less AlSo$_4$$\^$+/, CaSo$\sub$(aq)/, and MgSo$\sub$4(aq)/. Ferrous iron is present mostly as free Fe$\^$2+/, and FeSo$\sub$4(aq)/ and ferric iron exists predominantly as Fe(OH)$_2$$\^$+/, with less FeSo$\sub$4(aq)/, Fe(OH)$_2$$\^$-/, FeSo$_4$$\^$-/ and Fe$\^$3+/, respectively Al exists as free Al$\^$3+/, AlOH$_2$$\^$-/, (AlSo$_4$)$\^$+/, and Al(So$_4$)$\^$2-/. Fe is generally saturated with respect to hematite, magnetite, and goethite, with nearly saturation with lepidocrocite. Aluminum and sulfate are supersaturated with respect to predominant alunite and less jubanite, and they approach a saturation state with respect to diaspore, gibbsite, boehmite and gypsum. In the case of waters associated with whitish precipitates mainly composed of basaluminite, Al is present as predominant Al$\^$3+/ and Al(SO$_4$)$\^$+/, with less Al(OH)$\^$2+/, Al(OH)$_2$$\^$+/ and Al(SO$_4$)$\^$2-/. According to calculation for the mineral saturation, aluminum and sulfate are greatly supersaturated with respect to basaluminite and alunite. Diaspore is flirty well supersaturated while jubanite, gibbsite, and boehmite are already supersaturated, and gypsum approaches its saturation state. The observation that the only mineral phase we can easily detect in the whitish precipitate is basaluminite suggests that growth rate of alunite is much slower than that of basaluminite. Neutralization of acid mine drainage due to the dilution caused by the dilution effect due to mixing of unpolluted waters prevails over the buffering effect by the dissolution of carbonate or aluminosilicates. The main factors to affect color change are variations in aqueous geochemistry, which are controlled by dilution effect due to rainfall, water mixng from adjacent creeks, and the extent to which water-rock interaction takes place with seasons. pH, Fe, Al and SO$_4$ contents of the creek water are the most important factors leading to color changes in the precipitates. A geochemical cycle showing color variations in the precipitates provides the potential control on acid mine drainage and can be applied as a reclamation tool in a temperate region with four seasons.

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한식당의 위생관리 현황 평가 및 위험요인 중심의 위생교육용 포스터 개발 (Current Status of Sanitation Management Performance in Korean-Food Restaurants and Development of the Sanitary Training Posters Based on their Risk Factors)

  • 김선정;이나영;장혜자;곽동경
    • 한국식생활문화학회지
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    • 제23권5호
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    • pp.582-594
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    • 2008
  • This study aimed at evaluating current sanitation management performances in Korean-Food restaurants by their operation types and to develop sanitary training posters based on the risk factors, in an attempt to improve the level of sanitation management in Korean food service facilities. Eighteen Korean-food restaurants that are managed by franchisor, franchisees as well as self-managed with large-scale and small-scale restaurants in Seoul and Gyeonggi-Do, were evaluated by on-the-spot inspectors with an auditing tool consisting of three dimensions, nine categories and thirty four items. Data were analyzed using SPSS. The total score of each group showed that restaurants managed by franchisees ranked the highest (59 out of 100 points), while self-managed, small-scale restaurants ranked the lowest (44 out of 100 points). In the categorization of sanitation management compliance, the dimensions of food hygiene during production recorded the lowest compliance rate of 47.7% (22.89/48.0 points) followed by the dimension of environmental hygiene 59.3% (20.17/34.0 points) and personal hygiene 60.5% (10.89/18.0 points). This indicated the need for urgent improvement. The items which showed the lowest compliance rates were 'proper thawing of frozen foods' (0%), 'notifying and observing heating/reheating temperature' (6%), 'using of hand-washing facility and proper hand-washing' (33%), 'monitoring temperature of frozen-foods and cold-foods' (35%), and 'prevention of cross-contamination' (36%) among thirty four items. Self-managed, small-scale restaurants, in particular, needed to improve sanitary practices such as 'sanitation education for employee', 'verifying the employee health inspection reports', 'storing food on the shelves 15 cm distance away from the wall', 'suitability of ventilation capacity of hoods' and 'cleanliness of drainage'. On the basis of the findings of this study, we developed sanitary training posters, especially for small-scale restaurant operators. This could be an effective tool to educate food service employees on sanitary knowledge and principles and could be used to improve the existing sanitary conditions in Korean food service facilities.