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  • 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...
  • 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 ...
  • LA

  • Climate change, uncertainty, and consequent risks :Opportunities for forest management adaptation in Britain

    • Authors: van der Veen, A.; Petr, M.;  Advisor: -;  Participants: - (2014)

  • Thesis explore uncertainty from a decision maker’s perspective; investigate uncertainty from a modeller’s perspective ;reports on the outputs from the drought risk assessment across Britain for the three major species and provides a better understanding of quantified climate change uncertainty; highlights changes of the main forest ecosystem goods and services under climate change impacts over the next 80 years, and suggests how they can be incorporated within the dynamic adaptive policy pathways approach modified for forestry application; reports on changes in forest planners’ decisions about expiry dates for forestry management actions due to new climate change information and discuss the barriers for uptake of this information in the forest planning; reflects on the key findings,...
  • BB

  • Door recognition in cluttered building interiors using imagery and lidar data

    • Authors: Díaz-Vilariño, L.;  Advisor: -;  Participants: - (2014)

  • Building indoors reconstruction is an active research topic due to the importance of the wide range of applications to which they can be subjected, from architecture and furniture design, to movies and video games editing, or even crime scene investigation. Among the constructive elements defining the inside of a building, doors are important entities in applications like routing and navigation, and their automated recognition is advantageous e.g. in case of large multi-storey buildings with many office rooms. The inherent complexity of the automation of the recognition process is increased by the presence of clutter and occlusions, difficult to avoid in indoor scenes. In this work, we present a pipeline of techniques used for the reconstruction and interpretation of building interi...
  • LA

  • Geostatistical and space geodetic methods applied to 3D coseismic displacement field : mapping earthquakes from space

    • Authors: Stein, A.; Yaseen, M.;  Advisor: -;  Participants: - (2014)

  • Thesis gives detailed overview and scope of the dissertation; provides horizontal displacement map using optical remote sensing ASTER image pair bracketing the 2005 Kashmir earthquake in Pakistan; presents LOS (line-of-sight) coseismic displacement results calculated by InSAR technique; the application of pixel tracking technique for producing horizontal coseismic displacements for both ascending and descending orbit ASAR images; presents the three displacement maps describing the orthogonal displacement components of the 3D coseismic field for 2003 Bam earthquake; presents a synthesis of the results produced during the research work, and their discussion.
  • BB

  • A method to reconstruct the solar - induced canopy fluorescence spectrum from hyperspectral measurements

    • Authors: Zhao, Feng;  Advisor: -;  Participants: - (2014)

  • A method for canopy Fluorescence Spectrum Reconstruction (FSR) is proposed in this study, which can be used to retrieve the solar-induced canopy fluorescence spectrum over the whole chlorophyll fluorescence emission region from 640–850 nm. Firstly, the radiance of the solar-induced chlorophyll fluorescence (Fs) at five absorption lines of the solar spectrum was retrieved by a Spectral Fitting Method (SFM). The Singular Vector Decomposition (SVD) technique was then used to extract three basis spectra from a training dataset simulated by the model SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes). Finally, these basis spectra were linearly combined to reconstruct the Fs spectrum, and the coefficients of them were determined by Weighted Linear Least Squares (WLLS) fitti...
  • BB

  • An architecture for integration of multidisciplinary models

    • Authors: Belete, Getachew F.;  Advisor: -;  Participants: - (2014)

  • Integrating multidisciplinary models requires linking models: that may operate at different temporal and spatial scales; developed using different methodologies, tools and techniques; different levels of complexity; calibrated for different ranges of inputs and outputs, etc. On the other hand, integration of models requires us to address technical, semantic, and dataset aspects of interoperability. So we need a genuine techniques that enable us to integrate various domain specific models for interdisciplinary study. In this research work, we investigated best practices of System Integration, Enterprise Application Integration, and Integration Design Patterns. We developed an architecture of a multidisciplinary model integration framework that brings these three aspects of integratio...
  • LA

  • Areal uncertainty in traffic island polygons extracted from airborne laser point clouds

    • Authors: Stein, A.; Zhou, L.;  Advisor: -;  Participants: - (2014)

  • Thesis proposes and implements a curbstone detection method in both ALS and MLS data; proposes and implements an application of random sets to model uncertainty of road polygons extracted from airborne laser points; proposes and implements a random set approach for modelling integrated uncertainties of traffic islands derived from airborne laser scanning points and focuses on the impact caused by planimetric and vertical errors as well as the point density; proposes and implements an approach for uncertainty modelling of traffic islands using geometrically constrained random sets in airborne laser points.