• Title/Summary/Keyword: projected area

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Octree model based fast three-dimensional object recognition (Octree 모델에 근거한 고속 3차원 물체 인식)

  • 이영재;박영태
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.9
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    • pp.84-101
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    • 1997
  • Inferring and recognizing 3D objects form a 2D occuluded image has been an important research area of computer vision. The octree model, a hierarchical volume description of 3D objects, may be utilized to generate projected images from arbitrary viewing directions, thereby providing an efficient means of the data base for 3D object recognition. We present a fast algorithm of finding the 4 pairs of feature points to estimate the viewing direction. The method is based on matching the object contour to the reference occuluded shapes of 49 viewing directions. The initially best matched viewing direction is calibrated by searching for the 4 pairs of feature points between the input image and the image projected along the estimated viewing direction. Then the input shape is recognized by matching to the projectd shape. The computational complexity of the proposed method is shown to be O(n$^{2}$) in the worst case, and that of the simple combinatorial method is O(m$^{4}$.n$^{4}$) where m and n denote the number of feature points of the 3D model object and the 2D object respectively.

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오염토양 정화의 비용편익분석 -독일 오스나부릭 도시 사례-

  • 강동규
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.20-24
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    • 2004
  • The aim of this study was to analyse the cost-benefit-ratio of a soil remediation project. The target of the study was the 'Altablagerung Osnabrueck-Wueste' the largest inhabited former landfill site in Germany. The determination of benefit resulting from the soil remediation was quantified with the help of willingness-to-pay(WTP) analysis (contingent valuation method, CVM). 400 households participated in the survey. The average WTP was 6.5 Euro per household per month or 78 Euro per house-hold per year. The projected benefit generated by the remediation (consumer value) for the population in the landfill area was determined to be 0.7 million Euro per year. Factors which influence the will-ingness to pay were evaluated. The most important factors were age, garden use and the prevailing concern about personal health. A computation of the cost-benefit relationship was made on the basis of three different scenarios, which differed in terms of the projected benefits. Finally the economical efficiency of the project was determined. With a projection of 18 years and upwards the remediation of the soil is economically worthwhile.

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An Object Representation System Using Virtual Space Coordinates

  • Ban, Kyeong-Jin;Kim, Jong-Chan;Kim, Eung-Kon
    • Journal of information and communication convergence engineering
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    • v.8 no.4
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    • pp.411-415
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    • 2010
  • Conventional Augmented Reality has used data gloves or markers for smooth interaction between objects and background. This causes inconvenience of use and lower immersion. To build up immersion in Augmented Reality, additional input devices must be removed. For this purpose, accurate recognition of space coordinates is needed even with no attachment of markers. This paper proposes a method to create virtual space coordinates for interaction without wearing additional input devices so as to improve immersion in Augmented Reality. The acquired image was projected to 2D space and vanishing lines were extracted to calculate the virtual space coordinates. Then the sizes of the inserted objects were varied in accordance with the size of the virtual coordinates area based on the image projected onto the 2D coordinates. This resulted in improved immersion. This method can increase the efficiency of object creation by excluding the use of a 3D modeler for creation of 3D objects.

The illumination system design of Integrated Screen 3D Display

  • Lin, Chu-Hsun;Lin, Chun-Chuan;Lo, Hsin-Hsiang;Chung, Shuang-Chao;Chen, Tian-Yuan;Wang, Chy-Lin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2009.10a
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    • pp.1379-1382
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    • 2009
  • The 3D display has been used in optical projection technology to connect twenty mini- projectors with seamless image tiling. In this way, we can improve the projected resolution by reducing each project screen and increase projected area by connect several mini-projectors. In this article, the illumination system uses the LED light source, non- telecentric structure and LCOS panel, and it's total length is less than 10 centimeter. It can build a seamless large display by tiling multiple projectors.

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Uncertainties estimation of AOGCM-based climate scenarios for impact assessment on water resources (수자원 영향평가를 위한 기후변화 시나리오의 불확실성 평가)

  • Park E-Hyung;Im Eun-Soon;Kwon Won-Tae;Lee Eun-Jeong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.138-142
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    • 2005
  • The change of precipitation and temperature due to the global. warming eventually caused the variation of water availability in terms of potential evapotranspiration, soil moisture, and runoff. In this reason national long-term water resource planning should be considered the effect of climate change. Study of AOGCM-based scenario to proposed the plausible future states of the climate system has become increasingly important for hydrological impact assessment. Future climate changes over East Asia are projected from the coupled atmosphere-ocean general circulation model (AOGCM) simulations based on Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 and B2 scenarios using multi-model ensembles (MMEs) method (Min et al. 2004). MME method is used to reduce the uncertainty of individual models. However, the uncertainty increases are larger over the small area than the large area. It is demonstrated that the temperature increases is larger over continental area than oceanic area in the 21st century.

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Projecting Future Paddy Irrigation Demands in Korea Using High-resolution Climate Simulations (고해상도 기후자료를 이용한 우리나라의 논 관개요구량 예측)

  • Chung, Sang-Ok
    • Journal of Korea Water Resources Association
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    • v.44 no.3
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    • pp.169-177
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    • 2011
  • The impacts of climate change on paddy irrigation water demands in Korea have been analyzed. High-resolution ($27{\times}27\;km$) climate data for the SRES A2 scenario produced by the Korean Meteorological Research Institute (METRI) and the observed baseline climatology dataset were used. The outputs from the ECHO-G GCM model were dynamically downscaled using the MM5 regional model by the METRI. The Geographic information system (GIS) was used to produce maps showing the spatial changes in irrigation water requirements for rice paddies. The results showed that the growing season mean temperature for future scenarios was projected to increase by $1.5^{\circ}C$ (2020s), $3.3^{\circ}C$ (2050s) and $5.3^{\circ}C$ (2080s) as compared with the baseline value (1971~2000). The growing season rainfall for future scenarios was projected to increase by 0.1% (2020s), 4.9% (2050s) and 19.3% (2080s). Assuming cropping area and farming practices remain unchanged, the total volumetric irrigation demand was projected to increase by 2.8% (2020s), 4.9% (2050s) and 4.5% (2080s). These projections are contrary to the previous study that used HadCM3 outputs and projected decreasing irrigation demand. The main reason for this discrepancy is the difference with the projected climate of the GCMs used. The temporal and spatial variations were large and should be considered in the irrigation water resource planning and management in the future.

Prediction of Climate Change Impacts on Streamflow of Daecheong Lake Area in South Korea

  • Kim, Yoonji;Yu, Jieun;Jeon, Seongwoo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.169-169
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    • 2020
  • According to the IPCC analysis, severe climate changes are projected to occur in Korea as the temperature is expected to rise by 3.2 ℃, the precipitation by 15.6% and the sea level by 27cm by 2050. It is predicted that the occurrence of abnormal climate phenomena - especially those such as increase of concentrated precipitation and extreme heat in the summer season and severe drought in the winter season - that have happened in Korea in the past 30 years (1981-2010) will continuously be intensified and accelerated. As a result, the impact on and vulnerability of the water management sector is expected to be exacerbated. This research aims to predict the climate change impacts on streamflow of Daecheong Lake area of Geum River in South Korea during the summer and winter seasons, which show extreme meteorological events, and ultimately develop an integrated policy model in response. We projected and compared the streamflow changes of Daecheong Lake area of Geum River in South Korea in the near future period (2020-2040) and the far future period (2041-2060) with the reference period (1991-2010) using the HEC-HMS model. The data from a global climate model HadGEM2-AO, which is the fully-coupled atmosphere-ocean version of the Hadley Centre Global Environment Model 2, and RCP scenarios (RCP4.5 and RCP8.5) were used as inputs for the HEC-HMS model to identify the river basins where cases of extreme flooding or drought are likely to occur in the near and far future. The projections were made for the summer season (July-September) and the winter season(November-January) in order to reflect the summer monsoon and the dry winter. The results are anticipated to be used by policy makers for preparation of adaptation plans to secure water resources in the nation.

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Implications of Impacts of Climate Change on Forest Product Flows and Forest Dependent Communities in the Western Ghats, India

  • Murthy, Indu K.;Bhat, Savithri;Sathyanarayan, Vani;Patgar, Sridhar;M., Beerappa;Bhat, P.R.;Bhat, D.M.;Gopalakrishnan, Ranjith;Jayaraman, Mathangi;Munsi, Madhushree;N.H., Ravindranath;M.A., Khalid;M., Prashant;Iyer, Sudha;Saxena, Raghuvansh
    • Journal of Forest and Environmental Science
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    • v.30 no.2
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    • pp.189-200
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    • 2014
  • The tropical wet evergreen, tropical semi evergreen and moist deciduous forest types are projected to be impacted by climate change. In the Western Ghats region, a biodiversity hotspot, evergreen forests including semi evergreen account for 30% of the forest area and according to climate change impact model projections, nearly a third of these forest types are likely to undergo vegetation type change. Similarly, tropical moist deciduous forests which account for about 28% of the forest area are likely to experience change in about 20% of the area. Thus climate change could adversely impact forest biodiversity and product flow to the forest dependent households and communities in Uttara Kannada district of the Western Ghats. This study analyses the distribution of non-timber forest product yielding tree species through a network of twelve 1-ha permanent plots established in the district. Further, the extent of dependence of communities on forests is ascertained through questionnaire surveys. On an average 21% and 28% of the tree species in evergreen and deciduous forest types, respectively are, non-timber forest product yielding tree species, indicating potential high levels of supply of products to communities. Community dependence on non-timber forest products is significant, and it contributes to Rs. 1199 and Rs. 3561/household in the evergreen and deciduous zones, respectively. Given that the bulk of the forest grids in Uttara Kannada district are projected to undergo change, bulk of the species which provide multiple forest products are projected to experience die back and even mortality. Incorporation of climate change projections and impacts in forest planning and management is necessary to enable forest ecosystems to enhance resilience.

Discharge Computation from Float Measurement in Vegetated Stream (부자 측정 시 식생을 고려한 유량산정에 관한 연구)

  • Lee, Tae Hee;Jung, Sung Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.39 no.2
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    • pp.307-316
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    • 2019
  • Development of vegetation in stream channel increases resistance to flow, resulting in increase in river stage upon flood and affecting change in stage-discharge relationship. Vegetation revealed in stream by water level reaching a peak and then declined upon flood is mostly found as prone. Taking an account of flow distribution with the number of vegetation, prone vegetation layer might be at height where discharge rate is zero (0) (Stephan and Guthnecht, 2002). However, there is a tendency that flow rate is overestimated when applying the height of river bed to flow area with no consideration of the height of vegetation layer in flow rate by float measurement. In this study, reliable flow measurement in stream with vegetation was calculated by measuring the height of vegetation layer after flood and excluding the vegetation layer-projected area from the flow area. The result showed the minimum 4.34 % to maximum 10.82 % of flow deviation depending on the scale of discharge. Accordingly, reliable velocity-area methods would be determined if vegetation layer-projected area in stream is considered in flow rate estimation using the flow area during the flood.

A Study on Compensation Management Geographic Information System Construction Using Cadastral Information (지적정보를 활용한 보상관리 지리정보시스템 구축에 관한 연구)

  • 심정민;이창경
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.11a
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    • pp.479-484
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    • 2004
  • It is the present situation that the relevant data with the compensation and payment is filed and managed in the form of document or Excell. In case of the large volume dam construction, the management of the data about the sinking areas is conducted inefficiently in view of time management and economy through using the administrative manpower and data formating manpower. There is also problem about where and how to keep the data owing to the enormous data. As a result of the raised questions, through constructing the system which is linked with the location information and property information which is relevant to the compensation to increase the applying value of the information about the compensation and apply document management system to the geographic information system, the management system through computerizing for searching the uncompensated areas in appropriate areas and compensation information in the compensated areas is projected. Through constructing geographic information system, it is expected to create various information effects, using the function of the necessary area search for the boundary survey, actual condition survey, uncompensated area search, and re-compensated area search.

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