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Life In Between: Prehispanic Settlement Patterns Of The Carabamba Valley, Northern Peru, Amedeo Sghinolfi Dec 2021

Life In Between: Prehispanic Settlement Patterns Of The Carabamba Valley, Northern Peru, Amedeo Sghinolfi

Electronic Thesis and Dissertation Repository

This dissertation is an archaeological study of the Carabamba Valley (ca. 150 - 3,500 m.a.s.l.) in Northern Peru, which aims to reconstruct settlement patterns through the longue durée (ca. 1800 B.C. - A.D. 1532). This study also documents the relations occupants of this frontier zone maintained with neighboring polities on the Peruvian North Coast (Virú Valley) and in the Northern Highlands. The valley features the resource-rich ecological niche called chaupiyunga, fed by rainwater that flows towards the Pacific Ocean and by a number of springs, where crops like coca, fruits, and vegetables can be easily grown. The Carabamba Valley also …


Intra-Field Nitrogen Estimation For Wheat And Corn Using Unmanned Aerial Vehicle-Based And Satellite Multispectral Imagery, Plant Biophysical Variables, Field Properties, And Machine Learning Methods, Jody Seymon Yu Nov 2021

Intra-Field Nitrogen Estimation For Wheat And Corn Using Unmanned Aerial Vehicle-Based And Satellite Multispectral Imagery, Plant Biophysical Variables, Field Properties, And Machine Learning Methods, Jody Seymon Yu

Electronic Thesis and Dissertation Repository

Management of nitrogen (N) fertilizers is an important agricultural practice and field of research to increase productivity, minimize environmental impacts and the cost of production. To apply N fertilizer at the right rate, time, and place depends on the crop type, desired yield, and field conditions. The objective of this study is to use Unmanned Aerial Vehicle (UAV) multispectral imagery, PlanetScope satellite imagery, vegetation indices (VI), crop height, leaf area index (LAI), field topographic metrics, and soil properties to predict canopy nitrogen weight (g/m2) of corn and wheat fields in southwestern Ontario, Canada. Random Forests (RF) and Support …


The Physical Properties Of Volcanic And Impact Melt, Gavin Douglas Tolometti Aug 2021

The Physical Properties Of Volcanic And Impact Melt, Gavin Douglas Tolometti

Electronic Thesis and Dissertation Repository

The emplacement mechanisms of lunar impact melt flows, that form from hypervelocity impact events, have been a subject of debate in the lunar science community, because of their unique physical properties that separate them from other geologic features. Understanding how lunar impact melt flows were emplaced on the surface of the Moon will not only grant us new information about the flow dynamics of impact melt but provide insight into the production and distribution of impact melt and how it built and modified the surfaces of planetary surfaces.

Lunar impact melt flows exhibit surface roughness textures and morphologies that are …


The Use Of Unmanned Aerial Vehicle Based Photogrammetric Point Cloud Data For Winter Wheat Intra-Field Variable Retrieval And Yield Estimation In Southwestern Ontario, Yang Song Nov 2020

The Use Of Unmanned Aerial Vehicle Based Photogrammetric Point Cloud Data For Winter Wheat Intra-Field Variable Retrieval And Yield Estimation In Southwestern Ontario, Yang Song

Electronic Thesis and Dissertation Repository

Precision agriculture uses high spatial and temporal resolution soil and crop information to control the crop intra-field variability to achieve optimal economic benefit and environmental resources sustainable development. As a new imagery collection platform between airborne and ground measurements, Unmanned Aerial Vehicle (UAV) is used to collect high spatial resolution images at a user selected period for precision agriculture. Most studies extract crop parameters from the UAV-based orthomosaic imagery using spectral methods derived from the satellite and airborne based remote sensing. The new dataset, photogrammetric point cloud data (PCD), generated from the Structure from Motion (SfM) methods using the UAV-based …


Seeing The Invisible: An Integrated Remote Sensing Approach To Mapping Buried Architecture At Las Colmenas, Virú Valley, Peru, Kayla C. Golay Lausanne Jul 2020

Seeing The Invisible: An Integrated Remote Sensing Approach To Mapping Buried Architecture At Las Colmenas, Virú Valley, Peru, Kayla C. Golay Lausanne

Electronic Thesis and Dissertation Repository

This thesis reports on the results of a survey project conducted in 2018 and 2019, intending to address two main research questions: (1) What remote sensing technique(s) worked best to identify buried features at Las Colmenas? (2) What combinations of techniques proved to be optimal for identifying buried features, and what are the benefits and limitations of the use of an integrated approach? This project incorporated two scales of analysis: macroscale optical and thermal Unmanned Aerial Vehicle (UAV) surveys and microscale Ground-Penetrating Radar (GPR), magnetic susceptibility, and magnetometry surveys. A side-by-side comparison proved the thermal UAV, GPR, and magnetic susceptibility …


Intra-Field Canopy Nitrogen Retrieval From Unmanned Aerial Vehicle Imagery For Wheat And Corn Crops In Ontario, Canada, Hwang Lee Jul 2020

Intra-Field Canopy Nitrogen Retrieval From Unmanned Aerial Vehicle Imagery For Wheat And Corn Crops In Ontario, Canada, Hwang Lee

Electronic Thesis and Dissertation Repository

The optimization of crop nitrogen fertilization to accurately predict and match the nitrogen (N) supply to the crop N demand is the subject of intense research due to the environmental and economic impact of N fertilization. Excess N could seep into the water supplies around the field and cause unnecessary spending by farmers. Understanding the detailed spatial information about a crop status is known as a farming management technique called precision agriculture, which allows farmers to maximize their yield and profit while reducing the inputs of fertilizers, pesticides, water, and insecticides.

The goal of this study is to document and …


Airborne Observations Of Thermal Anisotropy From Urban Residential Neighbourhoods In Salt Lake City, Utah, Samantha J. Claessens Jun 2020

Airborne Observations Of Thermal Anisotropy From Urban Residential Neighbourhoods In Salt Lake City, Utah, Samantha J. Claessens

Electronic Thesis and Dissertation Repository

Urban surface temperatures are important variables in urban climatological processes. This thesis examines the directional variability of remotely sensed urban surface temperatures (thermal anisotropy or Λ) for three vegetated residential neighbourhoods in Salt Lake City, Utah, USA. Airborne thermal remote sensing using a thermal imager sampled the directional brightness temperature (DBT) at three times within a day for each site. Results indicate that temporal variability over a 20 – 30-minute flight was not negligible. Average DBT were then extracted from atmospherically corrected images and plotted on polar plots. For low density residential neighbourhoods Λ is increased with increasing tree-canopy coverage …


Comparative Assessment Of Downscaling Methods And Application Towards Analysis Of Climate Change Impact On Urban Regions, Markus Eichenbaum Nov 2019

Comparative Assessment Of Downscaling Methods And Application Towards Analysis Of Climate Change Impact On Urban Regions, Markus Eichenbaum

Electronic Thesis and Dissertation Repository

Global climate models (GCM) are sophisticated numerical models used to make long term climate projections. However, the resolution of their output is too coarse for climate change related local impact studies on urban regional scales. Downscaling efforts are taken to address this and increase GCM projection resolution. Physical Scaling (SP) downscaling methodology attempts to incorporate the physical basis of dynamical downscaling efforts with the computational efficiency of statistical methods. In this study, North American Regional Reanalysis surface skin temperature and precipitation data for a 1°x1° region centered on Houston, TX are downscaled to a resolution of 500m via SP and …


Vegetation And Tree Species Classification Using Multidate And High-Resolution Satellite Imagery And Lidar Data, Matthew Roffey Aug 2019

Vegetation And Tree Species Classification Using Multidate And High-Resolution Satellite Imagery And Lidar Data, Matthew Roffey

Electronic Thesis and Dissertation Repository

Remote sensing can play a key role in understanding the makeup of urban forests. This thesis analyzes how high-resolution multispectral imagery, lidar point clouds, and multidate multispectral imagery allow for improved classification of London, Ontario’s urban forest. Chapter 2 uses object-based support vector machine classification (SVM) to classify five types of trees using features derived from Geoeye-1 imagery and lidar data. This results in an overall accuracy of 85.08% when features from both data sources are combined, compared with 77.73% when using only lidar features, and 71.85% when using only imagery features. Chapter 3 makes use of Planetscope and VENuS …


Empirical Analysis Of Urban Sprawl In Canadian Census Metropolitan Areas Using Satellite Imagery, 1986-2016, Xiaoxuan Sun Jul 2019

Empirical Analysis Of Urban Sprawl In Canadian Census Metropolitan Areas Using Satellite Imagery, 1986-2016, Xiaoxuan Sun

Electronic Thesis and Dissertation Repository

Major Canadian cities have experienced rapid sprawl in the last 30 years. This dissertation presents two studies that empirically examine the causes of urban sprawl, merging census socioeconomics data and satellite imageries of 11 major Census Metropolitan Areas (CMAs). The monocentric city model and the Tiebout model are the main traditional theories explaining urban boundary changes and mobility residential. The first study focuses on the cross-sectional comparison among the 11 CMAs in 2016. In the second study, we zoom into the Toronto CMA and examine the longitudinal changes in its urban coverage at the fringe. We detect land cover/use changes …


The Effect Of Sub-Facet Scale Geometry On Vertical Facet Temperatures In Urban Street Canyons, Rainer V.J. Hilland Oct 2018

The Effect Of Sub-Facet Scale Geometry On Vertical Facet Temperatures In Urban Street Canyons, Rainer V.J. Hilland

Electronic Thesis and Dissertation Repository

Surface temperature plays a key role in many micro-scale urban processes. Walls comprise a significant percentage of the urban surface, yet are under-represented by many methods of thermal remote sensing and not considered in detail by micro-scale surface temperature mod- els. This thesis presents a novel method of mobile thermal observation performed in urban street canyons in London, ON that uses a thermal imager as well as a visual spectrum camera to provide dense spatial and temporal resolution of micro-scale wall temperature distributions. Images are manually classified by a series of nominal variables and the resulting data set discusses the …


Tensor-Based Hyperspectral Image Processing Methodology And Its Applications In Impervious Surface And Land Cover Mapping, Boyu Feng Sep 2018

Tensor-Based Hyperspectral Image Processing Methodology And Its Applications In Impervious Surface And Land Cover Mapping, Boyu Feng

Electronic Thesis and Dissertation Repository

The emergence of hyperspectral imaging provides a new perspective for Earth observation, in addition to previously available orthophoto and multispectral imagery. This thesis focused on both the new data and new methodology in the field of hyperspectral imaging. First, the application of the future hyperspectral satellite EnMAP in impervious surface area (ISA) mapping was studied. During the search for the appropriate ISA mapping procedure for the new data, the subpixel classification based on nonnegative matrix factorization (NMF) achieved the best success. The simulated EnMAP image shows great potential in urban ISA mapping with over 85% accuracy.

Unfortunately, the NMF based …


Effects Of Aerial Lidar Data Density On The Accuracy Of Building Reconstruction, Peter Crawford Aug 2018

Effects Of Aerial Lidar Data Density On The Accuracy Of Building Reconstruction, Peter Crawford

Electronic Thesis and Dissertation Repository

Previous work has identified a positive relationship between the density of aerial LiDAR input for building reconstruction and the accuracy of the resulting reconstructed models. We hypothesize a point of diminished returns at which higher data density no longer contributes meaningfully to higher accuracy in the end product. We investigate this relationship by subsampling a high-density dataset from the City of Surrey, BC to different densities and inputting each subsampled dataset to reconstruction using two different reconstruction methods. We then determine the accuracy of reconstruction based on manually created reference data, in terms of both 2D footprint accuracy and 3D …


Crop Monitoring And Yield Estimation Using Polarimetric Sar And Optical Satellite Data In Southwestern Ontario, Chunhua Liao Jul 2018

Crop Monitoring And Yield Estimation Using Polarimetric Sar And Optical Satellite Data In Southwestern Ontario, Chunhua Liao

Electronic Thesis and Dissertation Repository

Optical satellite data have been proven as an efficient source to extract crop information and monitor crop growth conditions over large areas. In local- to subfield-scale crop monitoring studies, both high spatial resolution and high temporal resolution of the image data are important. However, the acquisition of optical data is limited by the constant contamination of clouds in cloudy areas. This thesis explores the potential of polarimetric Synthetic Aperture Radar (SAR) satellite data and the spatio-temporal data fusion approach in crop monitoring and yield estimation applications in southwestern Ontario.

Firstly, the sensitivity of 16 parameters derived from C-band Radarsat-2 polarimetric …


Evaluation Of The Uav-Based Multispectral Imagery And Its Application For Crop Intra-Field Nitrogen Monitoring And Yield Prediction In Ontario, Yang Song Aug 2016

Evaluation Of The Uav-Based Multispectral Imagery And Its Application For Crop Intra-Field Nitrogen Monitoring And Yield Prediction In Ontario, Yang Song

Electronic Thesis and Dissertation Repository

Unmanned Aerial Vehicle (UAV) has the capability of acquiring high spatial and temporal resolution images. This new technology fills the data gap between satellite and ground survey in agriculture. In addition, UAV-based crop monitoring and methods are new challenge of remote sensing application in agriculture.

First, in my thesis the potential of UAV-based imagery was investigated to monitor spatial and temporal variation of crop status in comparison with RapidEye. The correlation between red-edge indices and LAI and biomass are higher for UAV-based imagery than that of RapidEye. Secondly, the nitrogen weight and yield in wheat was predicted using the UAV-based …


Automated Impact Crater Detection And Characterization Using Digital Elevation Data, Ian M. Pritchard Aug 2016

Automated Impact Crater Detection And Characterization Using Digital Elevation Data, Ian M. Pritchard

Electronic Thesis and Dissertation Repository

Impact craters are used as subjects for the remote study of a wide variety of surface and subsurface processes throughout the solar system. Their populations and shape characteristics are collected, often manually, and analysed by a large community of planetary scientists. This research investigates the application of automated methods for both the detection and characterization of impact craters on the Moon and Mars, using machine learning techniques and digital elevation data collected by orbital spacecraft. We begin by first assessing the effect of lunar terrain type variation on automated crater detection results. Next, we develop a novel automated crater degradation …


Application Of Polarimetric Sar For Surface Parameter Inversion And Land Cover Mapping Over Agricultural Areas, Xiaodong Huang Jun 2016

Application Of Polarimetric Sar For Surface Parameter Inversion And Land Cover Mapping Over Agricultural Areas, Xiaodong Huang

Electronic Thesis and Dissertation Repository

In this thesis, novel methodology is developed to extract surface parameters under vegetation cover and to map crop types, from the polarimetric Synthetic Aperture Radar (PolSAR) images over agricultural areas. The extracted surface parameters provide crucial information for monitoring crop growth, nutrient release efficiency, water capacity, and crop production. To estimate surface parameters, it is essential to remove the volume scattering caused by the crop canopy, which makes developing an efficient volume scattering model very critical.

In this thesis, a simplified adaptive volume scattering model (SAVSM) is developed to describe the vegetation scattering as crop changes over time through considering …


Integration Of Multi-Temporal Optical And L-Band Synthetic Aperture Radar (Sar) Imagery For Hierarchical Agricultural Crop Classification In Northeastern Ontario, Canada, Autumn A. Gambles Jan 2015

Integration Of Multi-Temporal Optical And L-Band Synthetic Aperture Radar (Sar) Imagery For Hierarchical Agricultural Crop Classification In Northeastern Ontario, Canada, Autumn A. Gambles

Electronic Thesis and Dissertation Repository

This study integrated multi-temporal, multispectral optical and L-band synthetic aperture radar (SAR) imagery to classify agricultural crops throughout a single growing season in northeastern Ontario, Canada. Various optical and SAR band/date combinations were tested to identify optimal dates and datasets for crop classification at various phenological stages using both object-based decision tree rulesets and traditional per-pixel strategies. Object-based decision tree classification of 2 pairs of SPOT-5 optical and L-Band ALOS SAR imagery yielded crop identification accuracy results comparable with hierarchically masked per-pixel classification, with corn classes regularly achieving high classification accuracies (+90%). Regardless of classification approach, results indicate that at …


Multivariate Spatial Visualization Using Geoicons And Image Charts, Bo Shan Nov 2014

Multivariate Spatial Visualization Using Geoicons And Image Charts, Bo Shan

Electronic Thesis and Dissertation Repository

Spatial databases are growing in size and complexity, yet current visual data mining methods are challenged when it comes to multivariate spatial data. The specific research question addressed in this thesis is: how can spatial multivariate data be effectively visualized using an icon based non-fused co-visualization approach? The thesis presents a Python based design and implementation of a visualization program termed GeoIcon Viewer. The program incorporates two different visualization methods: GeoIcon Image Map and Region-of-Interest Image Layers Chart. The GeoIcon Image Map technique uses an icon to co-visualize up to nine attributes at a single location. The Region-of-Interest Image …


Automated Building Information Extraction And Evaluation From High-Resolution Remotely Sensed Data, Chuiqing Zeng Apr 2014

Automated Building Information Extraction And Evaluation From High-Resolution Remotely Sensed Data, Chuiqing Zeng

Electronic Thesis and Dissertation Repository

The two-dimensional (2D) footprints and three-dimensional (3D) structures of buildings are of great importance to city planning, natural disaster management, and virtual environmental simulation. As traditional manual methodologies for collecting 2D and 3D building information are often both time consuming and costly, automated methods are required for efficient large area mapping. It is challenging to extract building information from remotely sensed data, considering the complex nature of urban environments and their associated intricate building structures.

Most 2D evaluation methods are focused on classification accuracy, while other dimensions of extraction accuracy are ignored. To assess 2D building extraction methods, a multi-criteria …


Application Of Radarsat-2 Polarimetric Data For Land Use And Land Cover Classification And Crop Monitoring In Southwestern Ontario, Qin Ma Jun 2013

Application Of Radarsat-2 Polarimetric Data For Land Use And Land Cover Classification And Crop Monitoring In Southwestern Ontario, Qin Ma

Electronic Thesis and Dissertation Repository

Timely and accurate information of land surfaces is desirable for land change detection and crop condition monitoring. Optical data have been widely used in Land Use and Land Cover (LU/LC) mapping and crop condition monitoring. However, due to unfavorable weather conditions, high quality optical images are not always available. Synthetic Aperture Radar (SAR) sensors, such as RADARSAT-2, are able to transmit microwaves through cloud cover and light rain, and thus offer an alternative data source.

This study investigates the potential of multi-temporal polarimetric RADARSAT-2 data for LU/LC classification and crop monitoring in the urban rural fringe areas of London, Ontario. …


Object-Based Urban Building Footprint Extraction And 3d Building Reconstruction From Airborne Lidar Data, Ting Zhao Apr 2013

Object-Based Urban Building Footprint Extraction And 3d Building Reconstruction From Airborne Lidar Data, Ting Zhao

Electronic Thesis and Dissertation Repository

Buildings play an essential role in urban intra-construction, urban planning, climate studies and disaster management. The precise knowledge of buildings not only serves as a primary source for interpreting complex urban characteristics, but also provides decision makers with more realistic and multidimensional scenarios for urban management. In this thesis, the 2D extraction and 3D reconstruction methods are proposed to map and visualize urban buildings. Chapter 2 presents an object-based method for extraction of building footprints using LiDAR derived NDTI (Normalized Difference Tree Index) and intensity data. The overall accuracy of 94.0% and commission error of 6.3% in building extraction is …


Detection And Mapping Of Phragmites Australis Using High Resolution Multispectral And Hyperspectral Satellite Imagery, Nicholas J. Lantz Dec 2012

Detection And Mapping Of Phragmites Australis Using High Resolution Multispectral And Hyperspectral Satellite Imagery, Nicholas J. Lantz

Electronic Thesis and Dissertation Repository

Mapping invasive plant species is important to establish an invasion baseline, monitor plant propagation, and to implement an effective plan to deal with the invasion. In this thesis, methods are proposed to map invasive Phragmites australis in a Great Lakes coastal wetland. Chapter 2 presents an object-based Phragmites extraction method using Worldview-2 high-spatial-resolution satellite imagery. For the 4024 ha study area at Walpole Island,Ontario, 94% overall accuracy was achieved.

Chapter 3 uses CHRIS PROBA hyperspectral satellite imagery for mapping the pixel abundance of Phragmites using a spectral mixture analysis method. An evaluation method was developed to assess the accuracy of …