Forest plantations make up a large percentage of managed forest land globally. Assessing plantation productivity is vital from both commodity production and carbon management standpoints. Measuring the productivity of these areas is essential given their rapid growth and turnover. Transparent metrics to compare reported carbon storage with estimated values are required for internationally transferred mitigation outcomes under Article 6.2 of the Paris Agreement. Data from the Global Ecosystems Dynamics Investigation (GEDI) provide an excellent opportunity to measure plantation forests over large areas. We focused our efforts on Eucalyptus in southern Brazil and used data from an industrial partner to investigate plantation metrics (height, diameter, volume, stems per hectare, etc.) and to create a model of plantation diameter using Support Vector Regression (SVR). SVR enabled a robust model of tree diameter even given the heteroskedasticity and spatial auto correlation present in the GEDI data, which deleteriously impacted attempts at linear modeling. We could predict tree diameter in these plantations to within 1 cm using space-borne lidar, with broad implications for using space-borne lidars to monitor carbon accretion in secondary forest plantation. / Master of Science / Forest management practices have shifted in some cases to very crop-like forest plantings. These areas are functionally different from a 'natural' forest. Understanding the structure of these areas in a rapid and consistent manner is important to quantify the amount of carbon stored within these forests for international climate agreements such as the Paris Agreement. This effort focuses upon Eucalyptus forests in Southern Brazil. Using measurements from a lidar instrument (a lidar system fires a laser beam from space to the ground, recording the 'deflection' of the laser beam and the amount of time it takes to return to the sensor to measure features on the ground) we were able to measure the diameter of the trees to within a centimeter in these forests.

Electricity is a fundamental part of society, and ensuring its reliability for industries and households is essential for societal functioning. The growing reliance on electricity heightens our vulnerability to power outages, which can disrupt numerous societal functions. Enhancing the resilience of power grids against disruptions, particularly those caused by falling trees and encroaching vegetation, is imperative. With climate change scenarios leading to more frequent and intense extreme weather events, significant threats to power grids are increasing. Additionally, vegetation near powerlines can cause outages and safety hazards, necessitating effective vegetation management. Technological advancements, such as LiDAR (Light Detection and Ranging), offer new opportunities for monitoring and managing vegetation near powerlines. These technologies enable more accurate and efficient identification of potential risk zones, allowing for proactive management strategies. In Sweden, power outages due to falling trees are a common issue, with significant increases in outages during severe weather events like storms. The purpose of this thesis is to analyze tree areas that could pose a danger to powerlines due to their height if they fall, focusing on three different levels: the transmission, regional, and local electrical grids in the area of Sörfors. The method that was used involved the usage of Geographic Information Systems (GIS) and commercially available LiDAR-data acquired from SLU. The analysis revealed significant variation in the potential danger posed by trees to the powerlines among the transmission, regional, and local grids. The local grid is the most exposed to tall trees, while the regional powerline also is exposed in close proximity to some tall trees. The transmission grid, however, is safeguarded from tree-related dangers in the examined powerline corridor. To further enhance such analyses, higher resolution LiDAR data and precise geographical locations of the powerline poles and cables should be obtained.

The thesis aims to identify the different types of visual analysis in landscape assessment that can be used today and determine the versatility and suitability of the use of LiDAR technology to obtain visual analysis in landscape assessment at the municipal level, compared with current techniques in use. Visual analysis of the landscape assessment is currently carried out with geographic software information systems due to its appearance, which include tools for performing the visual analysis for the calculation of the viewshed from digital elevation models and various points. The visual analysis of the landscape assessment are relevant in the landscape management instruments of the specific regional regulations of Spain that transpose the European Landscape Convention. This research shows how LiDAR data from the Plan Nacional de Ortofotografía Aérea (PNOA) available at the Centro Nacional de Información Geográfica, and that geographic information systems can be used to perform the calculation of the analysis in the assessment of the landscape more precisely. Moreover, several interpolation methods have been tried to obtain the digital surface model in the municipality of Navajas. In the preparation of landscape studies of the Comunitat Valencia for the visual analysis are using digital terrain models obtained from the dimensions and curves in digital format with three-dimensional information at scale 1: 10,000 or digital terrain models with a resolution of one meter obtained from LiDAR data, which frequently omit vertical elements, vegetation, buildings or other elements of the physical environment are not incorporated. In many studies the viewshed has been generated with the absence of important elements of the landscape that obstruct the view of the observer. In the generation of the viewshed one can find at present a great diversity of software of geographic information systems just as many free as commercial. In this research a comparison of the viewshed obtained from different GIS programs frequently used in Spain, both free and commercial, is made, where relationships are established with the results obtained and the processing time is measured in the generation of a viewshed. It also was compared the visual analysis obtained from a digital terrain model and the result of a digital surface model to determine the similarities and differences between them. A comparative analysis of the visual analysis method included in the content of the Landscape Studies of the Comunitat Valenciana is carried out from the digital surface model obtained from the LiDAR data, a digital terrain model and a digital model of urban surface. This research proposes a methodology for carrying out the visual analysis at the project scale with the use of a identifying viewshed and the digital surface model obtained, where there is a comparison of the results with that of the digital urban surface model. / La tesis tiene como objetivo principal identificar los diferentes tipos de análisis visuales en la valoración del paisaje que pueden utilizarse actualmente y determinar la versatilidad e idoneidad del uso de la tecnología LiDAR para la obtención del análisis visual en la valoración del paisaje a escala municipal y de proyecto en comparación con las técnicas actuales en uso. El análisis visual de la valoración del paisaje se realiza actualmente con programas informáticos de sistemas de información geográfica desde su aparición, los que incluyen herramientas para la realización del análisis visual para el cálculo de la cuenca visual a partir de modelos digitales de elevación y varios puntos de observación. Los análisis visuales de la valoración del paisaje son relevantes en los instrumentos de gestión del paisaje de las normativas autonómicas específicas de España que trasponen el Convenio Europeo del Paisaje. Esta investigación muestra cómo pueden utilizarse los datos LiDAR del Plan Nacional de Ortofotografía Aérea (PNOA) disponibles en el Centro Nacional de Información Geográfica, y los sistemas de información geográfica, para realizar el cálculo del análisis en la valoración del paisaje de forma más precisa. Para ello se han probado varios métodos de interpolación para la obtención del modelo digital de superficie en el término municipal de Navajas. En la elaboración de los estudios de paisaje de la Comunitat Valencia para el análisis visual se están utilizando modelos digitales del terreno obtenidos a partir de las cotas y las curvas de nivel en formato digital con información tridimensional a escala 1:10.000 o modelos digitales del terreno con resolución de un metro obtenidos a partir de datos LiDAR, que omiten frecuentemente los elementos verticales, no se incorpora la vegetación, ni las construcciones ni otros elementos del medio físico. En muchos estudios se ha generado la cuenca visual con la ausencia de elementos importantes del paisaje que obstruyen la vista del observador. En la generación de la cuenca visual se puede encontrar actualmente gran diversidad de programas informáticos de sistemas de información geográfica tanto libres como comerciales. En esta investigación se realiza una comparación de la cuenca visual obtenida a partir de distintos programas SIG utilizados frecuentemente en España, tanto libres como comerciales, donde se establecen relaciones con los resultados obtenidos y se mide el tiempo de procesamiento en la generación de una cuenca visual. También se han comparado los análisis visuales obtenidos a partir de un modelo digital del terreno y el resultado de un modelo digital de superficie para determinar las similitudes y diferencias entre ellos. Se realiza análisis comparativo del método de análisis visual incluido en el contenido de los Estudios de paisaje de la Comunitat Valenciana realizado a partir del modelo digital de superficie obtenido a partir de los datos LiDAR, de un modelo digital del terreno y un modelo digital de superficie urbana. La investigación se propone una metodología para la realización del análisis visual a escala de proyecto con la utilización de una cuenca visual de identificación y del modelo digital de superficie obtenido, donde también se realiza una comparación de los resultados con el modelo digital de superficie urbana. / La tesi té com objectiu principal identificar els diferents tipus d'anàlisi visuals a la valoració del paisatge que es poden utilitzar actualment i determinar la versatilitat i idoneïtat de l'ús de la tecnologia LiDAR per a l'obtenció de l'anàlisi visual a la valoració del paisatge a escala municipal i de projecte en comparació amb les tècniques actuals en ús. L'anàlisi visual de la valoració del paisatge es realitza actualment amb programes informàtics de sistemes d'informació geogràfica des de la seua aparició, els que inclouen eines per la realització de l'anàlisi visual per al càlcul de la conca visual a partir de models digitals d'elevació i diversos punts de observació. Els anàlisis visuals de la valoració del paisatge son rellevants en els instruments de gestió del paisatge de les normatives específiques autonòmiques d'Espanya que transposen el Conveni Europeu del Paisatge. Aquesta investigació mostra com poden utilitzar les dades lidar del Plan Nacional de Ortofotografía Aérea (PNOA) disponibles al Centro Nacional de Información Geográfica, i els sistemes d'informació geogràfica, per realitzar el càlcul de l'anàlisi en la valoració del paisatge de forma més precisa, per això s'han provat diversos mètodes d'interpolació per a l'obtenció del model digital de superfície al terme municipal de Navajas. En l'elaboració dels estudis de paisatge de la Comunitat Valenciana per a l'anàlisi visual s'estan utilitzant models digitals del terreny obtinguts a partir de les cotes i les corbes de nivell en format tridimensional amb informació digital d'una escala 1: 10.000 o models digitals del terreny amb resolució d¿un metre obtinguts a partir de dades LiDAR, que ometen freqüentment els elements verticals, no incorpora la vegetació, ni les construccions ni altres elements del medi físic. al molts estudis s'ha generat la conca visual amb l'absència d'elements importants del paisatge que obstrueixen la vista de l'observador. A la generació de la conca visual es pot trobar actualment gran diversitat de programes informàtics de sistemes d'informació geogràfica del tant lliures com comercials. en aquesta investigació es realitza una comparació de la conca visual obtinguda a partir de diferents programes SIG utilitzats freqüentment a Espanya, tant lliures com comercials, on s'estableixen relacions amb els resultats obtinguts i es mesura el temps de processament en la generació d¿una conca visual. També s'han comparat les anàlisis visuals obtinguts a partir d¿un model digital del terreny i el resultat d'un model digital de superfície per determinar les similituds i diferències entre ells. Es realitza un anàlisi comparatiu del mètode d'anàlisi visual inclòs en el contingut dels estudis de paisatge de la comunitat valenciana realitzat a partir del model digital de superfície obtingut a partir de les dades LiDAR d¿un model digital del terreny i d¿un model digital de superfície urbana. La investigació es proposa una metodologia per la realització de l'anàlisi d'una escala de projecte amb la utilització d¿una conca visual d'identificació i del model digital de superfície obtingut visual, on també es fa una comparació dels resultats amb el model digital de superfície urbana. / Collado Latorre, JC. (2017). APLICACIÓN DE LA TECNOLOGÍA LiDAR EN EL ANÁLISIS VISUAL DE LA VALORACIÓN DEL PAISAJE [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86221

Il existe au Québec un cadastre vertical qui montre graphiquement la propriété dans le cas de la superposition de la propriété. De nombreux travaux se sont intéressés au besoin d'une représentation volumique cadastrale pour ce type de cas, mais peu d'études ont porté sur la question de l'acquisition des données. Nous nous intéressons ici à l'utilisation des LiDAR terrestres pour la modélisation 2D et 3D à des fins cadastrales, technique peu utilisée aujourd'hui pour ce type d'application. L'objectif est d'estimer la pertinence du LiDAR terrestre pour l'acquisition de données spatiales utiles à la production de représentations cadastrales 2D et 3D pour des condominiums. Cette étude, en collaboration avec le groupe VRSB, a porté sur deux cas réels de condominiums et a permis, via la comparaison de levés effectués au LiDAR terrestre et au distancemètre, de mettre en évidence les avantages et les inconvénients du LiDAR terrestre pour cette application.

Des études récentes ont montré qu'avec l'aide des scènes créées à partir d'environnements naturels tels que les forêts, nous pouvons avoir un impact significatif sur la réduction voire l'amélioration des symptômes de diverses maladies, dont la plus importante est la maladie d'Alzheimer. Les effets de ces études ont été recherchés au fil des ans et des résultats très prometteurs ont été obtenus. De nos jours, l'une des choses qui peut être très étonnante et intéressante est l'expérience de ces environnements naturels par la synthèse des scènes informatiques, notamment via les environnements de réalité virtuelle. Plus le niveau d'immersion de ces environnements naturels conçus en réalité virtuelle est élevé et meilleur, plus il peut contribuer à améliorer les symptômes du patient. L'une des méthodes nouvelles et innovantes pour concevoir et construire des environnements naturels tels que les forêts est l'utilisation de données des scanners laser, qui nous fournissent des résultats très réalistes. Pour cette raison, dans cette étude, nous présentons une forêt virtuelle dérivée de données LiDAR terrestre et améliorée grâce à des techniques d'effets spéciaux.

Tableau d’honneur de la Faculté des études supérieures et postdoctorales, 2009-2010 / La télédétection satellitaire offre de nouvelles promesses pour le suivi à grande échelle de territoires reculés, mais les capteurs multispectraux généralement utilisés pour ce type d’étude n’offrent pas une information suffisamment détaillée. Les capteurs lidar apportent une nouvelle vision des écosystèmes forestiers, par leur capacité à mesurer directement la structure verticale des éléments recouvrant le sol. Une méthode tirant avantage de ce type de données a été développée pour permettre de répondre à la problématique du suivi de la biomasse aérienne des écosystèmes forestiers du Québec, qui couvrent une superficie de 1.3 M Km2. Des équations allométriques permettent d’estimer la biomasse aérienne sèche pour l’ensemble des arbres d’une placette d’inventaire et le contenu en carbone équivaut à 50% de cette biomasse. À l’aide de données provenant d’un capteur lidar profileur aérien, une équation générique permettant d’estimer la biomasse de ces placettes a été développée (R2 = 0.65, n=207). Puis, en utilisant une carte de couverture du sol Landsat ETM+ et une carte des zones de végétation, des équations ont aussi été développées pour des strates représentant trois types de couverts forestiers répartis dans trois grandes zones de végétation (R2 variant de 0.51 à 0.79). Le système lidar aérien a aussi survolé quatre portions d’orbite du Geoscience Laser Altimetry System (GLAS), à bord du satellite ICESat. Les données de ces orbites du GLAS et d’un modèle numérique d’élévation SRTM ont été utilisées pour développer une équation permettant de prédire la biomasse aérienne sèche estimée par le lidar aérien (R2 = 0.59, n=1325). Les résultats obtenus de cette régression nous ont permis d’utiliser les 104 044 impulsions lidar de GLAS disponibles pour la zone d’étude pour estimer la biomasse aérienne sèche totale tant pour les principales zones de végétation que pour la zone d’étude en entier. Pour la zone d’étude, la biomasse est en moyenne de 39.0  2.2 (erreur type) Mg ha-1 pour un total de 4.9  0.3 Pg et sa distribution parmi les zones de végétation principales au Québec est 12.6% feuillus nordiques, 12.6% mélangés nordiques, 38.4% boréale commerciale, 13% boréale non-commerciale, 14.2% taïga, et 9.2% toundra arborée. Les forêts non-commerciales représentent 36% de la biomasse aérienne estimée alors que les forêts boréales représentent 51% de cette biomasse. / A method to estimate aboveground dry biomass of Quebec’s forest ecosystems was developed using data from a spaceborn lidar. The study area covers the portion of the province south of the treeline, an area of 1.3 M Km2. Biomass was first estimated for ground inventory plots using allometric equations. A small footprint laser profiler then flew over these inventory plots to develop a generic airborne lidar-based biomass equation (R2 = 0.65, n=207). As well, the Landsat ETM+ land cover map and the vegetation zone maps were used to develop stratified equations (R2 ranging between 0.51 and 0.79). The same airborne lidar system flew along four portions of orbits of the ICESat Geoscience Laser Altimeter System (GLAS). An equation was developed to predict airborne profiling lidar estimates of aboveground dry biomass from GLAS data and from the SRTM digital elevation model (R2 = 0.59, n=1325). These results allowed us to use the 104,044 GLAS pulses available over the study area to estimate the total aboveground dry biomass for the main vegetation areas of Quebec as well as for the entire study area. Biomass for the entire study area averaged 39.0  2.2 (standard error) Mg ha-1 and totalled 4.9  0.3 Pg with 36% of this biomass located in non-commercial forests and 51% located in the boreal forest (both commercial and non-commercial).

Ce mémoire décrit le développement d’une technique incohérente de détection LADAR à l’aide d’une diode laser à longueur d’onde accordable afin d’identifier un échantillon multicouches à distance avec une résolution submillimétrique. Les principes de LADAR ainsi que les techniques d’interférométrie utilisés pour la détection d’un échantillon multicouches sont présentés. Par la suite, les concepts théoriques essentiels pour ce mémoire sont décrits, en particulier l’interféromètre à fréquence accordable, la comparaison des mesures prises en réflexion et transmission, et l’effet des mesures prises à un angle d’incidence. La phase expérimentale consistait en une série d’essais en laboratoire pour valider le montage expérimental, ainsi qu’un programme diversifié de mesures extérieures avec une multitude de configurations d’échantillons multicouches. Les résultats concluants démontrent la capacité d’identifier et de définir des échantillons multicouches à distances, incluant lorsque mesurés à un angle d’incidence. / This thesis outlines the development of an incoherent LADAR detection technique using a tunable laser diode source to identify and characterize multilayer samples with sub-millimeter resolution at long-range distances. The principles of LADAR and interferometry techniques currently being utilized to detect a stratified medium are first described. This is followed by the theoretical concepts that underline the work of this thesis, where in particular the frequency swept interferometer, the comparison of measurements performed in reflection versus transmission, and the effects of off-axis measurements are explained. The experimental phase consisted of a series of indoor tests to validate the experimental setup and the signal analysis code, and a wide-ranging outdoor measurement programme with numerous configurations of multilayer samples. The results successfully demonstrate the ability to identify and characterize multilayer samples at long-range distances, including when there is an angle of incidence on the substrate.

This research underscores the importance of integrating the evolving LiDAR technology and GIS spatial analysis for effective management of urban environment, habitat conservation, and sustainable development planning. The study area of this research is the City of Denton which has undergone urban expansion leading to significant alterations in the city's land cover patterns. The methodologies developed in this study include collecting the data sources, and processing of LiDAR point clouds of years 2019 and 2020 to generate the digital elevation model (DEM), digital surface model (DSM), building height model (BHM), and canopy height model (CHM). The models could separate developed from undeveloped lands and identify upland and water-related habitats by the natural threshold in plant height and by proximity to water and FEMA 100-year flood zones. The results show that 18 % of the total area of the city is occupied by upland habitats while water-related habitats cover 16 % of the total area. Upland habitats are

The use of satellite and airborne remote sensing data to predict foliar macronutrients and pigments for a boreal mixedwood forest composed of black and white spruce, balsam fir, northern white cedar, white birch, and trembling aspen was investigated. Specifically, imaging spectroscopy (IS) and light detection and ranging (LiDAR) are used to model the foliar N:P ratio, macronutrients (N, P, K, Ca, Mg) and chlorophyll. Measurement of both foliar macronutrients and foliar chlorophyll provide critical information about plant physiological and nutritional status, stress, as well as ecosystem processes such as carbon (C) exchange (photosynthesis and net primary production), decomposition and nutrient cycling. Results show that airborne and spaceborne IS data explained approximately 70% of the variance in the canopy N:P ratio with predictions errors of less than 8% in two consecutive years. LiDAR models explained more than 50% of the variance in the canopy N:P ratio with similar predictions errors. Predictive models using spaceborne Hyperion IS data were developed with adjusted R2 values of 0.73, 0.72, 0.62, 0.25, and 0.67 for N, P, K, Ca and Mg, respectively. The LiDAR model explained 80% of the variance in canopy Ca concentration with an RMSE of less than 10%, suggesting strong correlations between forest height and Ca. Two IS derivative indices emerged as good predictors of chlorophyll across time and space. When the models of these two indices with the same parameters as generated from Hyperion data were applied to other years' data for chlorophyll concentration prediction, they could explain 71, 63 and 6% and 61, 54 and 8 % of the variation in chlorophyll concentration in 2002, 2004 and 2008, respectively with prediction errors ranging from 11.7% to 14.6%. Results demonstrate that the N:P ratio, N, P, K, Mg and chlorophyll can be modeled by spaceborne IS data and Ca can only be predicted by LiDAR data in the canopy of this forest. The ability to model the N:P ratio and macronutrients using spaceborne Hyperion data demonstrates the potential for mapping them at the canopy scale across larger geographic areas and being able to integrate them in future studies of ecosystem processes. / Ph. D.

With autonomy becoming a reality for passenger cars, developing an autonomous for tractor-trailers is the next step for driverless roads. Tractor-trailers are heavy, large, and have a pivot joint between the tractor and trailer that makes the movement between the two more complicated. The purpose of the research presented here is to determine the best forward "looking" perception sensor that will see far out enough for the vehicle to stop in time to avoid hitting an object. In order to determine the best sensor, a review of previous sensors and autonomous vehicle sensors will be explored along with the various perception technology. Additionally, a simulation of a tractor-trailer stopping was created to determine the range necessary for a forward perception sensor and when jackknifing may occur. The best brake type for a tractor-trailer will be recommended as well. Finally, the best forward sensor and senor layout for an autonomous tractor-trailer is made based upon the simulation results for the stopping distance of a tractor-trailer. The work, however, is not fully complete. A discussion of the future work and validation of the sensors selected will give future research goals. / Master of Science / With autonomy becoming a reality for passenger cars, developing an autonomous for tractor-trailers is the next step for driverless roads. Tractor-trailers are heavy, large, and have a pivot joint between the tractor and trailer that makes the movement between the two more complicated. The purpose of the research presented here is to determine the best forward “looking” perception sensor that will see far out enough for the vehicle to stop in time to avoid hitting an object. In order to determine the best sensor, a review of previous sensors and autonomous vehicle sensors will be explored along with the various perception technology. Additionally, a simulation of a tractor-trailer stopping was created to determine the range necessary for a forward perception sensor and when jackknifing may occur. The best brake type for a tractor-trailer will be recommended as well. Finally, the best forward sensor and senor layout for an autonomous tractor trailer is made based upon the simulation results for the stopping distance of a tractor-trailer. The work, however, is not fully complete. A discussion of the future work and validation of the sensors selected will give future research goals.