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  • BB

  • A web-based platform for remote sensing image annotation

    • Authors: Garcia-Pedrero, A.;  Advisor: -;  Participants: - (2016)

  • The generation of labeled data for training automated methods used in the analysis of remote sensing images is a challenging task. Approaches as Active Learning aim to perform accurate classifications in a scenario of a few annotated data. These approaches generally require the interaction between the user and the machine learning method during training phase. However, in the remote sensing area, it is difficult to find a tool that facilitates this interaction. In this work, an interactive web-based platform to perform the training of method for remote sensing image annotation by means of an active learning approach is proposed. The platform integrates open-source GIS technologies and object-based approach in order to facilitate the interaction between the user and the active learni...
  • BB

  • A web-based platform for remote sensing image annotation

    • Authors: Garcia-Pedrero, A.;  Advisor: -;  Participants: - (2016)

  • The generation of labeled data for training automated methods used in the analysis of remote sensing images is a challenging task. Approaches as Active Learning aim to perform accurate classifications in a scenario of a few annotated data. These approaches generally require the interaction between the user and the machine learning method during training phase. However, in the remote sensing area, it is difficult to find a tool that facilitates this interaction. In this work, an interactive web-based platform to perform the training of method for remote sensing image annotation by means of an active learning approach is proposed. The platform integrates open-source GIS technologies and object-based approach in order to facilitate the interaction between the user and the active learni...
  • LT

  • Acquisition and processing of point clouds to support building damage assessment :Powerpoint

    • Authors: Khoshelham, K.;  Advisor: -;  Participants: - (2013)

  • This lecture presents: Why building damage assessment?; Why point clouds?; Acquisition of point clouds; Classification of damaged roofs in aerial point clouds; Classification of damaged roofs in aerial point clouds; What are features of damaged/intact roof segments?; Feature selection; Visual analysis; Structural health monitoring.
  • BB

  • Bayesian integration of flux tower data into process-based simulator for quantifying uncertainty in simulated output

    • Authors: Rahul, Raj;  Advisor: -;  Participants: - (2014)

  • Parameters of a process-based forest growth simulator are difficult or impossible to obtain from field observations. Reliable estimates can, however, be obtained using calibration against observations of output and state variables. In this study, we present a Bayesian framework to calibrate the widely used process-based simulator BIOME-BGC against estimates of gross 5 primary production (GPP) data. We used GPP partitioned from flux tower measurements of a net ecosystem exchange over a 55 year old Douglas fir stand as an example. The uncertainties of both the BIOME-BGC parameters and the simulated GPP were estimated. The calibrated parameters leaf and fine root turnover (LFRT), ratio of fine root carbon to leaf carbon (FRC:LC), ratio of carbon to nitrogen in leaf (C:Nleaf), canopy wa...
  • BB

  • Bioenergy from low-intensity agricultural systems :an energy efficiency analysis

    • Authors: Arodudu, O.;  Advisor: -;  Participants: - (2017)

  • In light of possible future restrictions on the use of fossil fuel, due to climate change obligations and continuous depletion of global fossil fuel reserves, the search for alternative renewable energy sources is expected to be an issue of great concern for policy stakeholders. This study assessed the feasibility of bioenergy production under relatively low-intensity conservative, eco-agricultural settings (as opposed to those produced under high-intensity, fossil fuel based industrialized agriculture). Estimates of the net energy gain (NEG) and the energy return on energy invested (EROEI) obtained from a life cycle inventory of the energy inputs and outputs involved reveal that the energy efficiency of bioenergy produced in low-intensity eco-agricultural systems could be as much a...
  • BB

  • Bayesian integration of flux tower data into a process-based simulator for quantifying uncertainty in simulated output

    • Authors: Tol, C.V.D.; Raj, R.;  Advisor: -;  Participants: - (2017)

  • In this study, we present a Bayesian framework to calibrate the widely used process-based simulator Biome-BGC against estimates of gross primary production (GPP) data. We used GPP partitioned from flux tower measurements of a net ecosystem exchange over a 55-year-old Douglas fir stand as an example. The uncertainties of both the Biome-BGC parameters and the simulated GPP values were estimated. The calibrated parameters leaf and fine root turnover (LFRT), ratio of fine root carbon to leaf carbon (FRC : LC), ratio of carbon to nitrogen in leaf (C : Nleaf), canopy water interception coefficient (Wint), fraction of leaf nitrogen in RuBisCO (FLNR), and effective soil rooting depth (SD) characterize the photosynthesis and carbon and nitrogen allocation in the orest. The calibration improv...
  • LA

  • Biodiversity in fragmented key resource areas :Presistence of plant diversity and productivity in an intensely grazed key resource area

    • Authors: Skidmore, A.K.; Muthoni, F.K.;  Advisor: -;  Participants: - (2014)

  • Thesis investigates the drivers of large ungulate biomass density in the KRA along Lake Naivasha; investigates the impact of large ungulates grazing and rainfall on productivity (regrowth) and residual aboveground biomass of herbaceous plants; compares a novel method (ManyGLM) against the distance- based redundancy analysis (db-RDA) in detecting the multivariate effect of ungulate grazing on plant community composition and identification of the species that are most responsive to grazing; analyzes the impacts of continuous intense grazing by large herbivore on herbaceous plant diversity and composition in the fragmented KRA; evaluates the relative contribution of environmental heterogeneity and species dispersal limitation (spatial distances) on variation in plant beta-diversity in ...
  • BB

  • Bi-decadal groundwater level trends in a semi-arid south indian region: Declines, causes and management

    • Authors: Shukla, S.; Sishodia, R.P.;  Advisor: -;  Participants: - (2016)

  • India, world’s largest groundwater user (250 billion m3 yr−1) has been reported to experience declining groundwater levels. However, the statistical significance of the decline has not been analyzed to separate human effects from natural variability. Contrary to common perception of widespread groundwater declines only 22–36% of the wells showed statistically significant declines. The use of well depth during dry well periods may slightly underestimate the number of declining wells (by 1%) and rate of decline. Increase in groundwater irrigated area combined with rainfall and power subsidy policy, were the main causative factors for the decline. Groundwater decline after implementation of free-electricity policy in 2004 confirmed the nexus between power subsidy and groundwater. These...
  • BB

  • Bayesian multi-model projections of extreme hydroclimatic events under RCPs scenarios

    • Authors: Xia, J.; Sun, Q.;  Advisor: -;  Participants: - (2017)

  • A Bayesian multi-model inference framework was used to assess the changes in the occurrence of extreme hydroclimatic events in four major river basins in China (i.e., Liaohe River Basin, Yellow River Basin, Yangtze River Basin, and Pearl River Basin) under RCP2.6, RCP4.5, and RCP8.5 scenarios using multiple global climate model projections from the IPCC Fifth Assessment Report. The results projected more summer days and fewer frost days in 2006–2099. The ensemble prediction shows the Pearl River Basin is projected to experience more summer days than other basins with the increasing trend of 16.3, 38.0, and 73.0 d per 100 years for RCP2.6, RCP4.5 and RCP8.5, respectively. Liaohe River Basin and Yellow River Basin are forecasted to become wetter and warmer with the co-occurrence of in...
  • BB

  • Biofuels from agricultural biomass in Zimbabwe: Feedstock availability and energy potential

    • Authors: Yoshikawa, K.; Maqhuzu, A.B.;  Advisor: -;  Participants: - (2018)

  • Crop residues and animal dung can contribute a significant portion to the biomass available for conversion to biofuels in Zimbabwe. This paper will extend a quantitative methodology involving the use of probability distributions to rigorously address uncertainty in the quantification of this biomass. The results of 100 000 Monte Carlo simulations using Palisade’s @Risk tool indicates the following at a 90% confidence interval: 2.55-5.50 million Mg/yr. of crop residue and 2.99-4.99 million Mg/yr. of dung is generated. The total exploitable energy was estimated at an annual mean of 26.6 and 16.9 million GJ for crop residue and dung respectively.