• Title/Summary/Keyword: topography change

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A Study on the Dispersion of Air Pollutants in Local Circulation of Mesoscale (중규모 국지 순환에서 대기 오염 물질의 확산에 관한 연구)

  • 이화운;오은주
    • Journal of Environmental Science International
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    • v.3 no.1
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    • pp.39-47
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    • 1994
  • Dispersion characteristics of air pollutants in the mountainous coastal area are investigated in considering with the mesoscale local circulations using a two dimensional numerical model with two kinds of topograpy of 500m and 300m. In the model, land-sea breezes and mountain-valley wind are mainly considered under the condition of the absence of large scale prevailing flow in the circulation analysis, and the pollutants dispersion is traced by the Lagrangian methods. According to the results, the wind velocity is affected by topography and is stronger in the case of 500m height mountain than that of 300m, the Pollutants that source is near the coast transported over the mountain and dispersed to behind inland area. It is classified that the topography change control affects the wind velocity and the circulations. The pollutants that source is different transported and concentrated to behind inland and/or diffused to the sea area by the combination of the wind system with topographic changes. The results can be applied to the air pollution control with the arrangement design of industrial area and the planning of coastal developments.

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Estimation of Solar Radiation Distribution Considering the Topographic Conditions at Jeju Island (지형조건에 따른 제주도의 일사량 분포 추정)

  • Park, Jin Ki;Park, Jong Hwa
    • Journal of The Korean Society of Agricultural Engineers
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    • v.55 no.1
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    • pp.39-48
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    • 2013
  • The solar radiation is the primary energy source that drives many of the earth's physical and biological processes and climate change. Understanding its importance to the solar radiation observation is a key to understanding a broad range of natural processes, agricultural, energy and human activities. The purpose of this study is to estimate solar radiation using sunshine duration, and to estimate distribution of solar radiation using a topography factor considering surface slope and aspect in complex terrain. The result of regression analysis between ratio of solar radiation and sunshine duration from 2001 to 2010 shows high $R^2$ value of 0.878. Regression analyses indicated that topographic attributes including elevation, slope and aspect had significant effects on solar radiation. The variation of topographic factor with aspect and slope for the summer and winter are considered. The highest month of daily mean solar radiation at Jeju island appears in April of 20.61 $MJ{\cdot}m^{-2}{\cdot}day^{-1}$, and the lowest month appears in December of 6.90 $MJ{\cdot}m^{-2}{\cdot}day^{-1}$. These results provided useful quantitative information about the influence of topography on solar radiation in the island region.

AUTOMATIC DETECTION OF OIL SPILLS WITH LEVEL SET SEGMENTATION TECHNIQUE FROM REMOTELY SENSED IMAGERY

  • Konstantinos, Karantzalos;Demetre, Argialas
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.126-129
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    • 2006
  • The marine environment is under considerable threat from intentional or accidental oil spills, ballast water discharged, dredging and infilling for coastal development, and uncontrolled sewage and industrial wastewater discharges. Monitoring spills and illegal oil discharges is an important component in ensuring compliance with marine protection legislation and general protection of the coastal environments. For the monitoring task an image processing system is needed that can efficiently perform the detection and the tracking of oil spills and in this direction a significant amount of research work has taken place mainly with the use of radar (SAR) remote sensing data. In this paper the level set image segmentation technique was tested for the detection of oil spills. Level set allow the evolving curve to change topology (break and merge) and therefore boundaries of particularly intricate shapes can be extracted. Experimental results demonstrated that the level set segmentation can be used for the efficient detection and monitoring of oil spills, since the method coped with abrupt shape’s deformations and splits.

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A Study on the Phenomenon of O. M. Ungers School in Germany (독일 건축의 O. M. 웅어스 스쿨 현상에 관한 연구)

  • Yi, Eun-Young
    • Journal of architectural history
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    • v.25 no.1
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    • pp.69-83
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    • 2016
  • Classic rationalist architecture came to play an important role in modern architectural discourse in the 1970s. But it has declined since the death of its most representative architects Aldo Rossi and O. M. Ungers. However, the phenomenon to be noted is that a new momentum was brought to the German architectural scene through some remarkable achievements by the disciples of Ungers after 2000. This study aims to read this phenomenon on the topography of german architecture and to catch out what potential it has to create balance in the international architectural debate. It is not the aim to analyze a single architect in detail, but to compare some important architects like Hans Kollhoff, Max Dudler, Eun-Young Yi and Uwe $Schr{\ddot{o}}der$. And further the study will try to give an overview of how far this phenomenon can change the topography of the German architectural scene. The buildings that have been examined here are Daimler Chrysler Building, Grimm Zentrum, Stuttgart City Library, and Haus Hundertacht. Through this study, it was found that some architects continue the attitude and the architectural languages of O. M. Ungers and develope their own unique architecture. And this phenomenon has the potential to influence todays architectural debate on a global scale.

A Study on the Characteristic of Site Planning of Hadrian's Villa (하드리안 별장에서의 배치계획의 특성에 관한 연구)

  • Kim, Seok-Man
    • Journal of architectural history
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    • v.25 no.1
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    • pp.7-21
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    • 2016
  • The purpose of this paper is to study on the characteristic of site planning of Hadrian's villa. The whole site planning of Hadrian's villa can be divided by different characteristic four groups(I-IV). It is analysed to the whole site plan of such huge complex and the site planning of partial each group which is organically connected each other. The results of this study are as follows: 1. Hadrian's villa was arranged in adapt to natural condition according to a gentle inclination by topography and terrain of the whole site which many different buildings are oriented towards natural landscape of the site and the site surroundings. 2. The site planning of Hadrian's villa is composed of dividing into four groups as plan segmentalized through various land use plan, considering for territory of functional aspect and direction of axis formed by situation and direction of topography and terrain. 3. The concept of site planning to buildings of Hadrian's villa is composed through each other connection; the first, meeting, crossing and merging with each other from arrangement by several axises, the second, change of direction with as the center a part of corner of buildings and the third, facing or inserting system to side and side, side and a part of corner of building.

Seasonal Changes in Structure and Landscape of Urban Stream Corridor - In the Case of Gongji Stream in Chuncheon- (도시하천 하도구조와 경관의 계절변화 - 춘천시 공지천을 중심으로 -)

  • Jo Hyun-Kil;Han Gab-Soo
    • Journal of Environmental Science International
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    • v.14 no.8
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    • pp.739-748
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    • 2005
  • The purpose of this study is to analyze seasonal changes in structure and landscape of Gongji stream corridor in Chuncheon, and to suggest some guidelines to contribute to creating a desirable close-to- nature stream. The study seasonally surveyed floodplain and revetment conditions, channel micro-topography, streamflow level and velocity, and vegetational cover. Flooding, water level, and vegetation were major factors of affecting seasonal changes in streambed structure and stream landscape. Small sand bars and islands were considerably disturbed by flooding and water level change. However, large islands and sand bars in the upper and middle section of the study stream remained or reappeared even after flooding. Flooding also tended to repeat channel sedimentation at the same spot. Controlling water volume of the Euiam Lake, which is adjacent to the study stream, caused higher water level downstream in the dry seasons. The majority of vegetation in sand bars and islands was washed away by the floods. Vehicle passing, crop cultivation, and ball game were other elements which disturbed vegetation in the floodplain. Creating a close-to-nature stream should reflect micro-topographical changes of channel by flooding, prevent improper vehicle entry and human use, and remove concrete material in the revetment and floodplain.

TEXTURE AND RELATED MICROSTRUCTURE AND SURF ACE TOPOGRAPHY OF VAPOR DEPOSITS

  • Lee, Dong-Nyung
    • Journal of the Korean institute of surface engineering
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    • v.29 no.5
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    • pp.301-313
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    • 1996
  • The texture of vapor deposits(PVD and CVD) changes from the orientation that places the lowest energy lattice plane parallel to the substrate under the condition of low atom or ion concentration adjacent to the deposit, to the orientation that places the higher energy crystal planes parallel to the substrate as the atom or ion concentration adjacent to the deposit increases. However, in the early stage of deposition, the deposit-substrate interface energy and the surface energy constitute the most important energies of the system. Therefore, if the lattice match is established between the substrate and the deposit without generating much strain energy, the epitaxial growth takes place to reduce the interfacial energy. When the epitaxial growth does not take place, the surface energy is dominant in the early stage of deposition and the lowest energy crystal plane tends to be placed parallel to the substrate up to a critial thickness. The thickness depends on the deposition condition. If the deposition condition does not favor placing the lowest energy crystal plane parallel to the substrate, the initial texture will change to that compatible with the deposition condition as the film thickness increases, and the texture turnover thickness will be short. The microstructure and surface topography of deposits are related to their texture.

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Errors in light-emitting diodes positioning when curing bulk fill and incremental composites: impact on properties after aging

  • Abdulrahman A. Balhaddad;Isadora M. Garcia;Haifa Maktabi;Maria Salem Ibrahim;Qoot Alkhubaizi;Howard Strassler;Fabricio M. Collares;Mary Anne S. Melo
    • Restorative Dentistry and Endodontics
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    • v.46 no.4
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    • pp.51.1-51.13
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    • 2021
  • Objectives: This study aimed to evaluate the effect of improper positioning single-peak and multi-peak lights on color change, microhardness of bottom and top, and surface topography of bulk fill and incremental composites after artificial aging for 1 year. Materials and Methods: Bulk fill and incremental composites were cured using multi-peak and single-peak light-emitting diode (LED) following 4 clinical conditions: (1) optimal condition (no angulation or tip displacement), (2) tip-displacement (2 mm), (3) slight tip angulation (α = 20°) and (4) moderate tip angulation (α = 35°). After 1-year of water aging, the specimens were analyzed for color changes (ΔE), Vickers hardness, surface topography (Ra, Rt, and Rv), and scanning electron microscopy. Results: For samples cured by single-peak LED, the improper positioning significantly increases the color change compared to the optimal position regardless of the type of composite (p < 0.001). For multi-peak LED, the type of resin composite and the curing condition displayed a significant effect on ΔE (p < 0.001). For both LEDs, the Vickers hardness and bottom/top ratio of Vickers hardness were affected by the type of composite and the curing condition (p < 0.01). Conclusions: The bulk fill composite presented greater resistance to wear, higher color stability, and better microhardness than the incremental composite when subjected to improper curing. The multi-peak LED improves curing under improper conditions compared to single-peak LED. Prevention of errors when curing composites requires the attention of all personnel involved in the patient's care once the clinical relevance of the appropriate polymerization reflects on reliable long-term outcomes.

DETECTING LANDSLIDE LOCATION USING KOMSAT 1AND IT'S USING LANDSLIDE-SUSCEPTIBILITY MAPPING

  • Lee, Sa-Ro;Lee, Moung-Jin
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.840-843
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    • 2006
  • The aim of this study was to detect landslide using satellite image and apply the landslide to probabilistic landslide-susceptibility mapping at Gangneung area, Korea using a Geographic Information System (GIS). Landslide locations were identified by change detection technique of KOMSAT-1 (Korea Multipurpose Satellite) EOC (Electro Optical Camera) images and checked in field. For landslide-susceptibility mapping, maps of the topography, geology, soil, forest, lineaments, and land cover were constructed from the spatial data sets. Then, the sixteen factors that influence landslide occurrence were extracted from the database. Using the factors and detected landslide, the relationships were calculated using frequency ratio, one of the probabilistic model. Then, landslide-susceptibility map was drawn using the frequency ration and finally, the map was verified by comparing with existing landslide locations. As the verification result, the prediction accuracy showed 86.76%. The landslide-susceptibility map can be used to reduce hazards associated with landslides and to land cover planning.

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Extraction of Forest Resources Using High Density LiDAR Data (고밀도 LiDAR 자료를 이용한 산림자원 추출에 관한 연구)

  • Young Rak, Choi;Jong Sin, Lee;Hee Cheon, Yun
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.33 no.2
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    • pp.73-81
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    • 2015
  • The objective of this study is in investigating the research for more accurately quantify the information on mountain forest by using the data on high density LiDAR. For the quantitative analysis of mountain forest resources, we investigated the method to acquire the data on high density LiDAR and extract mountain forest resources. Consequently, the height and girth of a tree each mountain forest resources could be extracted by using the data on high density LiDAR. When using the data on low density LiDAR of 2.5points/m2 in average used to produce digital map, it was difficult to extract the exact height and girth of mountain forest resources. If using the data on high density LiDAR of 7points/m2 by considering topography, the property of mountain forest resources, data capacity and process velocity, etc, it was found that multitudinous entities could be extracted. It was found that mountain topography and mixed topography were generally denser than plane topography and multitudinous mountain forest resources could be extracted. Furthermore, it was also found that the entity at the border could not be extracted, when each partition was individually processed and the area should be subdivided and extracted by considering the process time and property of target area rather than processing wide area at once. We expect to be studied more profoundly the absorption quantity of greenhouse gas later by using information on mountain forest resources in the future.