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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
291

Influência da conicidade do pilar e tipo de agente cimentante na retentividade de coroas metálicas cimentadas sobre pilares personalizáveis de implantes

Dantas, Talita Souza 16 December 2011 (has links)
Several factors must be considered in the selection of angled abutments. In these situations, the clinician should find a practical way to overcome the lack of retention. The purpose of this study was to evaluate the bond strength of metallic crowns cemented to straight and angled customizable abutments with different definitive luting agents. Ninety one regular external hex analogs and abutments were divided in Control group (C): customizable straight abutment cemented with zinc phosphate (n = 10); three groups (n = 10) with 17° angled abutment cemented with zinc phosphate (A17ZP), Panavia F (A17RM) and RelyX U100 (A17R) cements and more three groups (n = 10) with 30° angled abutment also cemented with zinc phosphate (A30ZP), Panavia F (A30RM) and RelyX U100 (A30R) cements. The metal copings were cemented onto their corresponding metal dies and crowns cemented with Panavia F were pre-treated with an alloy primer containing an acid-phosphated monomer (MDP). Data from the all groups were compared to control group with a 1-way ANOVA (α=.05) and Dunnet s test, and comparison between tested groups were done with 2-way ANOVA (α=.05) and Tukey s test. SEM and CLSM evaluation were performed (n = 3) aiming to investigate microscopic features of the abutment-cement-crown interfaces. The mean force (SD) required to dislodge the crowns in the C, A17ZP, A17RM, A17R, A30ZP, A30RM and A30R groups was 357,26 (62,21) N; 251,50 (20,13) N; 397,05 (88,48) N; 328,71 (79,87) N; 276,70 (17,96) N; 377,81 (90,61) N and 335,42 (88,34) N respectively. Panavia F presented the higher tensile bond strength results and zinc phosphate the lower between the tested groups. Only A17ZP group was different from control group (p=.007) and the abutment taper has no influence in retentive values. Zinc phosphate showed an inhomogeneous cement line in SEM and CLSM analysis. The presence of MDP primer could be perceived in CLSM images of Panavia F group. Within the limitations of this in vitro study, the Panavia F presented the higher bonding strength between tested groups, however, all 3 cements tested were similar to control group except A17ZP group, showing that in the conditions of the study they all can be successfully used. / Vários fatores devem ser considerados na seleção dos pilares angulados, assim, muitas vezes, o clínico deve encontrar uma forma prática de superar a falta de retenção resultante das características desse tipo de pilar. O objetivo deste estudo foi avaliar a resistência de união de coroas metálicas cimentadas sobre pilares personalizáveis retos e angulados, cimentados com diferentes agentes de cimentação definitivos. Noventa e um análogos de implantes regulares do tipo hexágono externo foram divididos em Grupo controle (C): pilar reto personalizável cimentado com fosfato de zinco (n = 10); três grupos (n = 10) com pilares angulados de 17° cimentados com fosfato de zinco (A17F), Panavia F (A17RM) e RelyX U100(A17R) e ainda mais três grupos (n = 10) com pilares angulados de 30° também cimentados com cimento de fosfato de zinco (A30F), Panavia F (A30RM) e RelyX U100 (A30R). Coroas de Níquel-Cromo foram confeccionadas e cimentadas em seus pilares correspondentes sendo que as coroas cimentadas com Panavia F foram pré-tratadas com um primer para metal contendo monômero ácido fosfatado (MDP). Dados de todos os grupos foram comparados ao grupo controle por meio da análise de variância ANOVA - One way (α =0,05) e teste de Dunnet, e a comparação entre os grupos testados foi realizada por meio de análise de variância ANOVA Two way (α =0,05) e teste de Tukey. Ainda as avaliações em MEV e MVCL foram realizadas com 3 amostras representativas de cada grupo com o objetivo de investigar as características microscópicas das interfaces pilar-coroa-cimento. A média de força (DP) necessária para deslocar as coroas nos grupos C, A17F, A17RM, A17R, A30F, A30RM e grupos A30R foram, respectivamente, 357,26 (62,21) N; 251,50 (20,13) N; 397, 05 (88,48) N; 328,71 (79,87) N; 276,70 (17,96) N; 377,81 (90,61) N e 335,42 (88,34) N. O cimento Panavia F apresentou os resultados mais elevados de resistência a tração (RT) e o fosfato de zinco apresentou os menores valores de RT entre os grupos testados. Apenas o grupo A17F foi estatisticamente diferente do grupo controle (p = 0,007) e a inclinação das paredes axiais do pilar não influenciou os valores de retenção obtidos. O fosfato de zinco apresentou uma linha de cimentação não homogênea na análise em MEV e MVCL. A presença de primer contendo MDP pode ser percebida nas imagens de MVCL do grupo Panavia F. Dentro das limitações deste estudo in vitro, o Panavia F apresentou a maior resistência de união entre os grupos testados, no entanto, todos os três cimentos testados foram semelhantes ao grupo controle, exceto o grupo A17F grupo, mostrando que nas condições do estudo todos eles podem ser usados com sucesso. / Mestre em Odontologia
292

Vliv molekulové hmotnosti polypropylénu na izotermickou krystalizaci nanokompozitů / The influence of molecular weight of polypropylene on isothermal crystallization of nanocomposites

Krajčik, Ladislav Unknown Date (has links)
This work deals with the study of the influence of metallocene type polypropylene (mPP) molecular weight on isothermal crystallization of its nanocomposites filled with hydrophobic and hydrophilic nanosilica (1 and 2 vol.%). Real amount of nanosilica was determined by thermogravimetry. Isothermal crystallization was performed on differential scanning calorimeter (DSC) at 119–125 °C and observed in-situ under optical polarizing microscope (POM) at 128 °C using hot stage. The increase of mPP crystallinity degree in time was determined on DSC and spherulite type and growth rate was determined using POM. Supramolecular surface structure of the original and isothermally crystallited nanocomposites was observed directly or after chemical etching (mixture of mineral acids with KMnO4) on confocal laser scanning microscope. The crystal structure of mPP was in all tested materials verified by X-ray diffraction.
293

Caving mechanisms for a non-daylighting orebody

Banda, Sraj Umar January 2017 (has links)
The sublevel caving mining method is a mass production method with potentially very low operational costs. The success of this method is dependent on, among other factors, the cavability of the orebody and the overlying rock mass. However, caving of the surrounding rock mass also results in deformations in the cap rock as well as on the ground surface above the orebody being mined. From this follows that any existing infrastructure on the ground surface must be relocated as not to be affected by the mining-induced deformations.This thesis work was undertaken to bring about a better understanding of the rock mass behavior in the cap rock of non-daylighting orebodies, with particular application to the Printzsköld orebody as part of the LKAB Malmberget Mine. Rock testing, field observations and underground mapping was conducted to characterize the rock mass in the caving environment. A methodology for identifying the caving front based on seismic monitoring data was derived by studying the Fabian orebody (which has caved to surface), and using laser scanning data for validation. The methodology was then applied to the Printzsköld orebody to identify the caving front.Numerical modeling was performed for various scenarios of the rock mass as mining proceeded. Modeling included (i) stress analysis to understand stress changes and their effects on the rock mass behavior, (ii) discontinuum numerical modeling to quantify the influence of large-scale geological structures on the cave progression, and (iii) discontinuum cave modeling to simulate possible cave mechanisms in the cap rock more explicitly. Laser scanning together with seismic event data were used to calibrate the numerical models.The numerical simulation results showed that as mining progresses, the cap rock and hangingwall were exposed to stress changes that resulted in yielding. Two failure mechanisms were predominantly at play (i) shear failure (dominant in the cap rock) and (ii) tensile failure (dominant in the hangingwall). The presence of the large-scale structures affected thenearfield stresses through slip along the cave boundaries. The effect of the structures on the far field stresses were less significant.Discontinuum modeling to explicitly simulate failure and caving involved simulating the rock mass as a jointed medium using Voronoi tessellations in 2D, and bonded block modeling (BBM) in 3D. Both the 2D and the 3D modeling results showed fair agreement when comparing the inferred boundary of the seismogenic zone, with that identified from seismic monitoring data. Predictive numerical modeling was conducted for future planned mining to assess future cave development in the cap rock. The results from 3D modeling indicated that cave breakthrough for the Printzsköld orebody is expected when mining the 1023 m level, corresponding to approximately year 2022, as per current mining plans. The 2D model was non-conservative with cave breakthrough predicted to occur when mining the 1109 m level, corresponding to the year 2028.The estimated boundary between the seismogenic and yielded zones, as defined in the Duplancic and Brady conceptual model of caving, was coinciding with, or was close to, the cave boundary in the Printzsköld orebody. This may imply that in some areas the yielded zone was not present and that the Duplancic and Brady model may not be universally applicable. Additional work is required to verify this indication, as well as to fine-tune the modeling methodology.
294

Strength grading of structural timber and EWP laminations of Norway spruce : Development potentials

Oscarsson, Jan January 2012 (has links)
Strength grading of structural timber is a process by which value is added to sawn products. It is to the greater part carried out using machine grading based on statistical relationships between so called indicating properties and bending strength. The most frequently applied indicating property (IP) on the European market is the stiffness in terms of average modulus of elasticity (MOE) of a timber piece, although MOE is a material property that varies within timber. A major limitation of today’s grading methods is that the described relationships are relatively poor, which means that there is a potential for more accurate techniques. The main purpose of this research has been to initiate development of more accurate and efficient machine grading methods. Strength of timber is dependent on the occurrence of knots. At the same time, knot measures applied as indicating properties until today have shown to be poor predictors of strength. However, results from this research, and from previous research, has shown that not only size and position of knots but also fibre deviations in surrounding clear wood are of great importance for local stiffness and development of fracture under loading. Thus, development of new indicating properties which take account of knots as well as properties of surrounding fibres, determined on a very local scale, was considered as a possible path towards better strength grading. In the research, results from contact-free deformation measurements were utilized for analysis of structural behaviour of timber on both local and global level. Laser scanning was used for detection of local fibre directions projected on surfaces of pieces. Scanned information, combined with measures of density and average axial dynamic MOE, was applied for calculation of the variation of local MOE in the longitudinal board direction. By integration over cross-sections along a piece, a stiffness profile in edgewise bending was determined and a new IP was defined as the lowest bending MOE along the piece. For a sample of Norway spruce planks, a coefficient of determination of 0.68 was achieved between the new IP and bending strength. For narrow side boards to be used as laminations in wet-glued glulam beams, the relationship between IP and tensile strength was as high as 0.77. Since the intended use of the narrow boards was as laminations in wet-glued beams, the possibility of grading them in a wet state was also investigated. Grading based on axial dynamic excitation and weighing gave just as good results in a wet state as when the same grading procedure was applied after drying. It was also found that the relationship between the new IP and strength was dependent on what scale the IP was determined. Optimum was reached for moving average MOE calculated over lengths corresponding with approximately half the width of investigated pieces. Implementation of the new IP will result in grading that is more accurate than what is achieved by the great majority of today’s grading machines. The new method will probably also be particularly favourable for development of engineered wood products made of narrow laminations. / Hållfasthetssortering av konstruktionsvirke innebär att värdet på sågade produkter ökar. Sorteringen genomförs oftast med maskinella metoder baserade på statistiska samband mellan s.k. indikerande egenskaper och böjhållfasthet. Den indikerande egenskap (indicating property, IP) som är vanligast på den Europeiska marknaden är styvhet uttryckt som ett medelvärde för elasticitetsmodulen (modulus of elasticity, MOE) i ett virkesstycke, trots att MOE är en materialegenskap som varierar i virket. En betydande begränsning med dagens sorteringsmetoder är att de beskrivna sambanden är förhållandevis svaga, vilket innebär att det finns en potential för metoder med högre noggrannhet. Det huvudsakliga syftet med detta doktorandprojekt har varit att initiera en utveckling mot sådana metoder. Hållfasthet hos virke är beroende av förekomst av kvistar. Samtidigt har de kvistmått som fram till idag kommit till användning visat sig vara dåliga prediktorer av hållfasthet. Resultat från såväl denna som tidigare forskning har dock visat att inte bara kvistars storlek och läge, utan också variationen i fiberriktning i omgivande träfibrer, är av stor betydelse för lokal styvhet och brottförlopp under inverkan av last. Utveckling av nya IP som tar hänsyn till såväl kvistar som omgivande träfibrers egenskaper fastställda på mycket lokal nivå bedömdes vara en möjlig väg för att uppnå bättre hållfasthetssortering. I detta doktorandprojekt användes beröringsfri deformationsmätning för analys av det strukturella beteendet hos virkesstycken på såväl lokal som global nivå. Laserskanning utnyttjades för detektering av lokala fiberriktningar projicerade på virkesstyckenas ytor. Med utgångspunkt från skannad information, virkesdensitet och medelvärde för axiell dynamisk elasticitetsmodul kunde variationen i lokal elasticitetsmodul i virkesstyckenas längdriktning bestämmas. Genom integration över tvärsektioner längs ett virkesstycke kunde en profil över hur böjstyvheten i styva riktningen varierade i virkesstyckets längdriktning beräknas. En ny IP definierades som den lägsta elasticitetsmodulen i böjning utmed virkesstyckets längd. För ett urval av granplankor erhölls en förklaringsgrad på 0.68 mellan den nya indikerande egenskapen och böjhållfasthet. För smala sidobrädor avsedda att användas som lameller i våtlimmade limträbalkar var motsvarande förklaringsgrad mellan samma IP och draghållfasthet så hög som 0.77. Eftersom sidobrädorna var avsedda att användas som lameller i våtlimmade balkar genomfördes en studie avseende möjligheten att hållfasthetssortera i vått tillstånd med hjälp av axiell dynamisk excitering och vägning. Det visade sig att sådan sortering gav lika bra resultat som då samma metod användes efter torkning. Sambandet mellan den nya indikerande egenskapen och hållfasthet visade sig också vara beroende av på vilken lokal nivå som egenskapen beräknades. Optimum uppnåddes då den bestämdes som ett glidande medelvärde beräknat över en längd motsvarande ungefär halva virkesstyckets höjd. Implementering av den nya sorteringsmetoden kommer att resultera i sortering som är noggrannare än vad som kan erhållas med det stora flertalet av de sorteringsmetoder som finns idag. Den nya indikerande egenskapen kommer sannolikt att bli särskilt gynnsam att använda för utveckling av ingenjörsmässiga träprodukter bestående av smala lameller.
295

Érosion des falaises de la région Provence-Alpes-Côte d’Azur : évolution et origine de la morphologie côtière en Méditerranée : télédétection, géochronologie, géomorphologie / Rocky cliff erosion in the region Provence-Alpes-Côte d’Azur : evolution and origin of the coastal morphology in the Mediterranean : remote sensing, geochronology, geomorphology

Giuliano, Jérémy 16 December 2015 (has links)
L’intérêt croissant pour l’étude de la morphogénèse des côtes à falaises a permis de mieux appréhender les environnements méso/macrotidaux, mais en délaissant les environnements microtidaux. Pour cette raison, nous proposons d’étudier, à partir d’une approche exploratoire multi-échelle, la dynamique érosive des côtes à falaises en Méditerranée à travers l’exemple de la région Provence-Alpes-Côte d’Azur. Le choix de ce territoire s’est justifié en réponse à une problématique relative à la gestion des risques côtiers identifiée par le Conseil-Régional-PACA qui a financé ce travail doctoral. Les principaux objectifs visent à caractériser d’une part l’ampleur relative des occurrences érosives en fonction de la variabilité temporelle des forçages météo-climatiques, et d’autre part le degré du contrôle géologique sur la morphologie côtière. Toute la difficulté de l’étude réside donc dans l’optimisation des fenêtres d’observation afin de distinguer les comportements érosifs. Nous proposons donc de tester l’apport de quatre méthodes permettant de définir si l’érosion se produit de manière (1) continue à l’échelle annuelle (levés LiDAR embarqués depuis un bateau), (2) chronique à l’échelle séculaire (orthophotographies aériennes) et (3) exceptionnelle voir (4) catastrophique sur les temps propres à l’Holocène et au Quaternaire (datations aux cosmogéniques in situ 36Cl et analyses morphométriques). Au regard des résultats mesurés et interprétés, il apparaît que l’activité gravitaire produite au cours du XXe siècle (érosion moyenne de l’ordre du cm.an-1) est très faible par rapport aux environnements méso/macrotidaux / Increasing interest in studying rocky cliff coastline morphogenesis allowed a better understanding of meso/macrotidal environments, but let microtidal environments apart. Thus we propose studying the dynamic of cliff coastlines erosion in Mediterranean in the South-East of France, through a multi-scale explorative approach. This doctoral work was supported by the region Provence-Alpes-Côte d’Azur, which identified a problematic in relation with coastal hazard management. The main objectives aim at characterizing on one hand how the temporal variability of meteorologic and climatic forcings affects the magnitude of erosion, and on other hand to which extent the geological setting controls the coastline morphology. The great challenge of this work therefore consists in optimizing the observation range in order discriminate erosive behaviours. Thus we propose assessing the contribution of four methods in determining whether erosion takes place (1) continuously at annual scale (boat-borne laser scanning surveys), (2) chronic at secular scale (aerial orthophographies)and (3) exceptional even (4) catastrophic over the characteristic timescales of Holocene and Quaternary (cosmic ray exposure dating from in-situ 36Cl and morphometric analysis). The interpretation of the results shows that erosion rate observed through the XXth century (order of magnitude of cm.y-1) is very low compared to meso/macrotidal environments. However at timescales ranging from pluri-secular (0.29 ka BP) to pluri-millenar (6.8 ka BP), exceptional storms surges of +3 NGF could initiate an erosion process resulting in the formation of horizontal shore platforms.
296

STUDY OF ENERGY ABSORPTION IN MICRO – STRUT LATTICE STRUCTURE PRODUCED BY SELECTIVE LASER MELTING / STUDY OF ENERGY ABSORPTION IN MICRO – STRUT LATTICE STRUCTURE PRODUCED BY SELECTIVE LASER MELTING

Vrána, Radek January 2019 (has links)
Předložená dizertační práce je součástí většího výzkumného projektu, který si klade za cíl využití mikro prutové konstrukce vyrobené technologií SLM jako absorbér rázové energie s přesně navrženými vlastnostmi. Hlavním cílem práce je vývoj numerického modelu deformačního chování mikro-prutové konstrukce vyrobeného technologií Selective Laser Melting (SLM) z materiálu AlSi10Mg. Aby bylo možné dosáhnout hlavního cíle dizertační práce, bylo nutné analyzovat vliv procesních parametrů technologie SLM na tvorbu vnitřních materiálových vad a drsnost povrchu při výrobě mikro-prutové konstrukce. Tyto imperfekce degradují její mechanické vlastnosti a jejich odstranění zlepší možnosti a přesnost numerické predikce. Výsledky ukazují významný vliv dvou hlavních parametrů – skenovací rychlosti laseru a výkonu laseru. Na základě těchto poznatků byly dále definovány parametry vstupní energie Ein a lineární energie Elin, které zahrnují oba zmíněné parametry a byly definovány jejich limitní hodnoty pro minimalizaci vzniklých imperfekcí. Deformační chování vyrobené mikro-prutové konstrukce bylo analyzováno na navrženém pádové zařízení, které umožňuje testování s dopadovou energií až 120 J. Deformační chování je vyhodnocováno s využitím obrazové analýzy záznamu vysoko rychlostní kamery a silového průběhu z tenzometru. Výsledky analýzy byly využity pro validaci numerického modelu v programu ANSYS Explicit, do kterého byly implementovány poznatky o reálném tvaru vyrobeného mikro-prutového materiálu ve formě eliptického modelu geometrie a informace o reálných mechanických vlastnostech ve formě vyvinutého materiálového modelu. Výsledné porovnání výsledků experimentu s predikcí numerického modelu ukazují dobrou shodu v místě maximálního zatížení Fmax (odchylka 5 %) i průběhu celé deformace vzorku. Tyto poznatky budou v budoucnu využity při návrhu absorbéru energie s definovanými mechanickými vlastnostmi.
297

Měření posunů a přetvoření střešní konstrukce sportovní haly / Deformation Measurement of the Roof Structure of a Sport Hall

Klinčík, Radoslav January 2021 (has links)
Diploma thesis describes the measurement and evaluation of displacements and deformations of the wooden roof structure of the aquapark hall in Brno – Kohoutovice. Part of the work is devoted to the preparation and testing of used devices and tools. The main part of the work consists of performing one stage of measurement using the polar method and the laser scanning method. The polar method measurement is compared with the results of the polar method of the previous stage. The next part of the work deals with the comparison of the polar method and the laser scanning method measured in the last stage. The results achieved are interpreted in the final part of the work.
298

Měřická dokumentace památkového objektu v areálu hradu Veveří / Metric survey documentation of historic building in the area of Veveří castle

Velecká, Kateřina January 2021 (has links)
The diploma thesis deals with the production of metric survey documentation of part of historic building in the area of Veveří castle, namely two buildings located on the so-called "Příhrádek" in the form of a ground plan and section in the scale of 1:50 and elevations in the scale of 1:100. The thesis contains a theoretical part describing methods of surveying monuments, their outcomes and used software. And a practical part that deals with the measurement itself and the following procession leading to the production of graphical outcomes.
299

Podklady pro tvorbu mapy pro orientační běh / Data for the Creation Orienteering Maps

Panchártek, Jan January 2013 (has links)
This thesis is about using airborne laser scanning data for making maps for Orienteering. In this thesis were used altimetry data DMR 4G and DMR 5G. These data are provided by ČUZK. The control measuring was made in choosen area to verify the accuracy. In this thesis is described procedure of data collection and their treatment. The results of this thesis are two illustrations of the orienteering maps.
300

Analyse von full-waveform Flugzeuglaserscannerdaten zur volumetrischen Repräsentation in Umweltanwendungen

Richter, Katja 05 December 2018 (has links)
Wissenschaftliche Untersuchungen von terrestrischen und aquatischen Ökosystemen erfordern präzise Informationen über die dreidimensionale Struktur des ökologischen Systems. Full-waveform Flugzeuglaserscannerdaten eignen sich hervorragend zur Charakterisierung von Ökosystemen und bilden eine ideale Basis für die vollständige volumetrische Repräsentation der Vegetations- und Gewässerstruktur in einem Voxelraum. Die Voxelattribute werden dabei aus der digitalisierten Wellenform abgeleitet. Jeder emittierte Laserpuls wird von Dämpfungseffekten beeinflusst, die durch Teilreflexionen auf seinem Weg durch die unterschiedlichen Vegetations- oder Wasserschichten entstehen. Dadurch ist die Struktur im unteren Bereich der empfangenen Rohsignale unterrepräsentiert. Die im Rahmen dieser Arbeit entwickelten innovativen Methoden zur Analyse von full-waveform Daten ermöglichen die Generierung einer radiometrisch korrigierten Voxelraumrepräsentation. Voraussetzung dafür ist die numerisch stabile Rekonstruktion des effektiven differentiellen Rückstreuquerschnitts mit geeigneten Entfaltungs- und Regularisierungsverfahren. Das Kernstück der Analyse bildet die Beschreibung der Signaldämpfung mit Hilfe geeigneter Modelle. Auf Grundlage dieser Modelle wurden neuartige Korrekturverfahren zur Kompensation der Signaldämpfung erarbeitet, wobei der Korrekturterm direkt aus dem differentiellen Rückstreuquerschnitt abgeleitet wird. Die Grundidee der entwickelten Methode ist das schrittweise Anheben der Signalintensität in Abhängigkeit von der individuellen Historie jedes Laserpulses. Die Resultate der vorliegenden Arbeit tragen dazu bei, die in full-waveform Daten enthaltenen Informationen über die Vegetations- und Gewässerstruktur zugänglich zu machen. Weiterhin zeigen die hier präsentierten Ergebnisse, dass die Limitierungen bestehender Auswertemethoden, welche weitgehend auf die Extraktion diskreter Maxima und die Erzeugung volumetrischer Repräsentationen aus diskreten 3D Punktwolken beschränkt sind, überwunden werden können. / The scientific investigation of terrestrial and aquatic ecosystems requires precise information on the three-dimensional structure of the ecologic system. Full-waveform airborne laser scanner data are an ideal basis for the complete volumetric representation of vegetation and water structure in a voxel space. Due to attenuation effects, caused by partial reflections during the laser pulse propagation through the vegetation or water column, each individual laser pulse echo is significantly modified. As a result, the structure in the lower parts of the vegetation or water column is underrepresented in the digitized waveform. Within this research, novel and innovative methods were developed, which enable the generation of a radiometrically correct voxel space representation. Therefore, a numerically stable reconstruction of the effective differential backscattering cross section utilizing appropriate deconvolution and regularization techniques is required. The essential element of the analysis is the description of the signal attenuation using applicable mathematical models. For this purpose, novel correction methods compensating the signal attenuation based on these models were developed. The correction term is directly derived from the differential backscatter cross section. The basic idea is a gradually increase of the signal amplitudes depending on the individual history of each laser pulse. The results gained in this work contribute to an improved access to the information on vegetation and water structure, contained in full-waveform laser scanner data. Furthermore, it is possible to overcome limitations of existing approaches, which are mainly based on the extraction of discrete maxima.

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