• 제목/요약/키워드: Occurrence aspect

검색결과 183건 처리시간 0.025초

공간정보 기반 산사태 발생지역 예측비율 평가 (The Evaluation on the Prediction Ratio of Landslide Hazard Area based on Geospatial Information)

  • 이근상;이호준;고신영;조기성
    • 지적과 국토정보
    • /
    • 제44권2호
    • /
    • pp.113-124
    • /
    • 2014
  • 최근 집중호우에 의한 산사태 발생이 빈번해짐에 따라 산사태 취약지역을 분석하고 산사태 발생을 예측하기 위한 다양한 연구들이 진행되고 있다. 본 연구에서는 산사태 발생지역의 토양특성을 분석하였으며, 배수 특성별 우도비를 평가한 결과 배수가 좋은 토양에서 산사태 발생 가능성이 높게 나타났다. 또한 DEM 자료에서 추출한 경사도의 우도비를 평가한 결과 $20{\sim}40^{\circ}$ 경사구간에서 산사태 발생 가능성이 높게 나타났다. 그리고 공간분석에 의한 사면방향도의 우도비를 평가한 결과 북향에서 산사태 발생 가능성이 높게 나타났다. 아울러 토양배수, 경사도 그리고 사면방향도의 우도비를 중첩하여 산사태 취약도를 평가할 수 있었으며, 산사태 발생지역에 대하여 분석과 검증 프로세스를 수행함으로써 미래 산사태 발생 예측비율을 평가할 수 있었다.

관리조방적 옥상녹화지의 식재식물에 따른 이입식물 출현 양상 (An Occurrence Aspect of Invasive Plants According to Planted Plants in Extensive Rooftop Greening)

  • 한이채;이은희
    • 한국환경복원기술학회지
    • /
    • 제14권3호
    • /
    • pp.71-84
    • /
    • 2011
  • The purpose of this study is to suggest sustainable management of rooftop greening areas. This research is conducted to analyze birth-and-breeding state of planted plants set in extensive rooftop greening, and to examine occurrence aspect of invasive plants and its changes, some features of invasive plants on which can make a basic material for management program of planted plants as a whole. The experimental site is on the rooftop green area of Seoul Women's University which was constructed in 2007. The using method was monitoring rooftop greening areas and analyzing occurrence aspect of invasive plants and its changes by planted plants. Invasive plants were investigated six times overall in April, June, September, November of 2008, and April & June of 2009. As a result, 26 families and 66 species were found invaded. Of which 14 species of Gramineae were invaded the most remarkably. Through these study, it could be inferred some features of invasive plants and major region for it. After the analysis get done about feature of invasive plants, it shows that some invasive plants of all 66 species in total came out, otherwise occurred in a certain time of season. Within the researches eriod showed a higher incidence was found in Artemisia princeps, Conyza canadensis, Coreopsis anceolata, Equisetum arvense, Erigeron annuus, Oxalis corniculata, invasive plant have a lower incidence of plants were identified as Aster koraiensis, Dendranthema zawadsbum. So, when the plan to set a management device regarding occurrence aspect of invasive plants in accordance with planted plants on extensive rooftop greening, it was found that a sustainable & rational management device is desperately needed there for invasive & planted plants of the target area.

환경 친화 건축의 생성과 발생적 개념에 관한 연구와 사례 (A Study on the notion of occurrence and formation within green Architecture)

  • 김경숙;강승모;김승귀
    • 한국실내디자인학회논문집
    • /
    • 제25호
    • /
    • pp.295-300
    • /
    • 2000
  • This study basically is an attempt to categorize green architecture as the notion of occurrence and formation. In doing so would enable to seek for an insight of methodological matrix in green architecture. Which methodology should be arrived at to suit to which typology of green architecture. Moreover, the notion of occurrence is a fundamental principle to bring socialism into architecture. Therefore, it implies selecting which methodology to make green architecture can be associated with its communal sense and its appropriation is usually determine in a specific typology such as social program, community enlightenment and so on. At the same time, whether the notion of formation or occurrence, it is important to make clear insight the appropriation and alternation of technology while attempted to make green architecture. In a practical sense, this study ultimately proposes a critical aspect internationalism in the category of green architecture and speculates appropriate green architecture in substantial way.

  • PDF

나일론 섬유의 형상비 및 혼입률 변화에 따른 고강도 콘크리트의 폭렬특성 (Spalling Properties of High Strength Concrete Made with Various Aspect Ratios and Fiber Contents of Nylon Fiber)

  • 송용원;허영선;이성연;한창평;양성환;한천구
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2007년도 춘계학술논문 발표대회
    • /
    • pp.55-58
    • /
    • 2007
  • This study investigates the spatting properties of high strength concrete, $60\sim80MPa$ class, designed with diverse aspect ratios and fiber content of nylon(NY). Test showed that increase of fiber content and aspect ratio in concrete decreased the fluidity of fresh concrete, especially for 1580 and 3000 aspect ratio of fiber. As for the compressive and tensile strength, adding NY fiber did not significantly affect the values In the range of high strength. After completing the fire test, the specimens containing both 750 and 1000 aspect ratios of fiber protected the spatting occurrence even in 0.05vol.% of fiber content. This specimens indicated the residual compressive strength ratio at 37%, showing the most favorable value among other specimens. Therefore, it is demonstrated that to protect the spalling in high strength concrete considering the effective fluidity, strength and economic efficiency altogether, adding 0.05vol.% of NY fiber with 750 aspect ratio Is beneficial.

  • PDF

Multi-temporal image derived Ratio Vegetation Index and NDVI in a landslide prone region

  • Paramarthalingam, Rajakumar;Shanmugam, Sanjeevi
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
    • /
    • pp.257-259
    • /
    • 2003
  • Landuse maps are prepared from satellite imagery and field observations were conducted at various locations in the study area. Compared to the field data and NDVI and RVI thematic maps, NDVI is better than RVI, because it compensates for changing illumination conditions, surface slope, aspect and other factors. Clouds, water and snow have negative values for RVI and NDVI. Rock and bare soils have similar reflectance in both NIR and visible band, so RVI and NDVI are near zero. In forest areas with good vegetation cover, NDVI is high and landslide occurrence is less. But if annual and biennial vegetations are present and if cultivation practices are changed frequently, NDVI is medium and landslide occurrence is moderate. In areas where deforestation and settlement is in progress, NDVI is less and landslide occurrence is more. The NDVI FCC thematic map may be used as an important layer in GIS application for landslide studies. Analyzing other layers such as slope, rainfall, soil, geology, drainage, lineament, etc with NDVI FCC layer will give a better idea about the identity of landslide prone areas.

  • PDF

가스저장탱크의 부식피로균열 특성에 관한 연구 (Study on the Characteristics of Corrosion Fatigue Crack for Gas Storage Tanks)

  • 임우조;신종대
    • 수산해양기술연구
    • /
    • 제34권1호
    • /
    • pp.30-36
    • /
    • 1998
  • Recently, with rapid increase of gas demand, there occurs much interest their security of safety in the gas storage tanks and pressure vessels etc. In order to solve the problems, the occurrence of corrosion fatigue crack and the propagation behavior must be investigated. Especially the occurrence of corrosion fatigue crack and the propagation behavior in the part which has concentrated stress or defects, must be studied more carefully. In this paper, the high-tensile steel of SPV 50 which is much used for building the LPG storage tanks was tested by the use of a plane bending corrosion fatigue tester under the various marine environments and in the air. These experiments were done to investigate the corrosion fatigue crack propagation behavior, the variation of aspect ratio for part through crack and electro-chemical characteristics of the metal. The main results obtained are as follows ; 1. Comparing the same surface crack length with the crack depth, the crack depth toward the thickness of specimen in air propagated faster than that in corrosion environment. 2. The aspect variation of the half elliptical crack can be estimated as following equation; b/a=i-jb/t where a : surface crack length, b : crack depth, t : specimen thickness, i,j : experimental constants but the slope j is decreased as specific resistance decreases. 3. As the specific resistance of corrosion environment decrease or the corrosion fatigue crack propagates, the corrosion potential become less noble.

  • PDF

바람의 발생빈도와 속도에 따른 전송 비래염분 정량화 (Quantization of Transmitted Incoming Salt According to Wind Occurrence Frequency and Wind speed)

  • 조규환;이해승;김우재;안재철;박동천
    • 한국건축시공학회:학술대회논문집
    • /
    • 한국건축시공학회 2012년도 추계 학술논문 발표대회
    • /
    • pp.267-268
    • /
    • 2012
  • To evaluate the incoming salt quantitatively which is the reason of salt attack is a very important aspect to calculate the durability life of the structure. Incoming salt is influenced by various weather changes during the transmission and consequently, the changes of incoming salt quantity occur. Therefore, the study to analyze incoming salt quantity was executed which are changed by the weather environments (occurrence frequency of wind direction / wind speed); study results showed that influences to the changes of incoming salt quantity are bigger than those of wind speed, compared with the frequencies.

  • PDF

APPLICATION OF LOGISTIC REGRESSION MODEL AND ITS VALIDATION FOR LANDSLIDE SUSCEPTIBILITY MAPPING USING GIS AND REMOTE SENSING DATA AT PENANG, MALAYSIA

  • LEE SARO
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
    • /
    • pp.310-313
    • /
    • 2004
  • The aim of this study is to evaluate the hazard of landslides at Penang, Malaysia, using a Geographic Information System (GIS) and remote sensing. Landslide locations were identified in the study area from interpretation of aerial photographs and from field surveys. Topographical and geological data and satellite images were collected, processed, and constructed into a spatial database using GIS and image processing. The factors chosen that influence landslide occurrence were: topographic slope, topographic aspect, topographic curvature and distance from drainage, all from the topographic database; lithology and distance from lineament, taken from the geologic database; land use from TM satellite images; and the vegetation index value from SPOT satellite images. Landslide hazardous area were analysed and mapped using the landslide-occurrence factors by logistic regression model. The results of the analysis were verified using the landslide location data and compared with probabilistic model. The validation results showed that the logistic regression model is better prediction accuracy than probabilistic model.

  • PDF

공간 데이터베이스를 이용한 1991년 용인지역 산사태 분석 (Landsilde Analysis of Yongin Area Using Spatial Database)

  • 이사로;민경덕
    • 자원환경지질
    • /
    • 제33권4호
    • /
    • pp.321-332
    • /
    • 2000
  • The purpose of this study is to analyze landslide that occurred in Yongin area in 1991 using spatial database. For this, landslide locations are detected from aerial photographs interpretation and field survey. The locations of landslide, topography, soil, forest and geology were constructed to spatial database using Geographic Information System (GIS). To establish occurrence factors of landslide, slope, aspect and curvature of topography were calculated from the topographic database. Texture, material, drainage and effective thickness of soil were extracted from the soil database, and type, age, diameter and density of wood were extracted from the forest database. Lithology was extracted from the geological database, and land use was classified from the TM satellite image. Landslide was analyzed using spatial correlation between the landslide and the landslide occurrence factors by bivariate probability methods. GIS was used to analyze vast data efficiently and statistical programs were used to maintain specialty and accuracy. The result can be used to prevention of hazard, land use planning and construction planning as basic data.

  • PDF