TLS, Lidar

In recent years, both airborne and terrestrial laser scanning developed to a standard technique for acquiring information on terrestrial landscapes. Here forest inventory and orchard management is considered. Inventory and parameterization of individual trees in orchards and forests are of large interest in nowadays society because of the potential of economical maximization of orchard production and the sustainable management of forests.

Quercus serrata is a valuable deciduous oak native to East Asia. Despite its potential for producing high-quality wood, Quercus serrata remains underutilized in commercial forestry, mainly confined to traditional uses like shiitake mushroom cultivation. This study models its growth in Japan using Terrestrial Laser Scanning (TLS) data, applying crop tree models inspired by Central European practices on broadleaved species, and evaluating how varying automation levels in point cloud data processing affect model accuracy and forest management decisions. From data collected across 20 survey plots, we segmented 558 Quercus serrata trees, extracting parameters like diameter at breast height (at 1.3 m height, DBH), tree height (TH), crown diameter (CD), and branch-free bole length (BFBL) using semi-automated, automated, and manual measurements. We developed models for TH (semi-automated: pseudo R 2 = 0.65, automated: pseudo R 2 = 0.59), CD (semi-automated: pseudo R 2 = 0.75, automated: pseudo R 2 = 0.62), and BFBL (semi-automated: pseudo R 2 = 0.33, automated: pseudo R 2 = 0.27, manual: pseudo R 2 = 0.49). Quercus serrata exhibited typical traits of a lightdemanding oak, including early height growth and natural branch shedding. Using our models, we simulated forest management scenarios based on target DBH and annual radial increment (IR). We recommend adjusting tree spacing to address slow average IR (2.2 mm/yr) and implementing a twophase system to enhance wood quality. Refining algorithms for BFBL measurements is critical, as discrepancies significantly impact management decisions like thinning timing and harvest volume.

A simple extension method of the ICP algorithm using point quality based on the distance and incident angle is presented for improving the registration accuracy of TLS point clouds. First, using a structured point cloud representation, the distance and incident angle of each point are calculated. Then, quality measures for the distance and incident angle are defined, considering the relationship between them and the scanning errors. Finally, an extension method of the ICP algorithm by the weighting using the estimated point qualities is described. A method for efficient matching using point properties is also introduced. The proposed method is applied to two datasets of TLS point clouds of a small plant and an outdoor environment, and the effectiveness is evaluated by comparing registration errors with the ground truths obtained using the scan target and a total station.

A simple extension method of the ICP algorithm using point quality based on the distance and incident angle is presented for improving the registration accuracy of TLS point clouds. First, using a structured point cloud representation, the distance and incident angle of each point are calculated. Then, quality measures for the distance and incident angle are defined, considering the relationship between them and the scanning errors. Finally, an extension method of the ICP algorithm by the weighting using the estimated point qualities is described. A method for efficient matching using point properties is also introduced. The proposed method is applied to two datasets of TLS point clouds of a small plant and an outdoor environment, and the effectiveness is evaluated by comparing registration errors with the ground truths obtained using the scan target and a total station.

The presented research aims to define a parametric modelling methodology that allows, in short time and at a sustainable cost, the digital acquisition, modelling and semantic structuring of urban city blocks to facilitate 3D city modelling applied to historic centres. The methodology is based on field surveying and derives 3D data for the realisation of a parametric City Information Model (CIM). This is pursued through the adoption of parametric modelling as main method combined with AI procedures like supervised machine learning. In particular, the Visual Programming Language (VPL) Grasshopper is adopted as main working environment. The methodology proposed, called Scan-to-CIM, is developed to automate the cognitive operations of interpretation and input of surveying data performed in the field in order to create LoD4 city block models in a semi-automatic way. The proposed Scan-to-CIM methodology is applied to a city block located in the historic centre of Catania, Italy.

Software-defined networking (SDN) introduces innovative network management and flexibility but also exposes new vulnerabilities. This paper investigates the impact of rogue switches on SDN controllers, detailing various attack methodologies, including Denial-of-Service (DoS), traffic diversion, rule modification, and false reporting. Through experimentation with both basic and optimized Distributed Denial-of-Service (DDoS) attacks on Pox and Ryu controllers, I demonstrate significant degradation in network performance. The study also explores advanced rogue switch behaviors, such as cloning and diverting traffic, selective rule manipulation, and information extraction about the controller's state. I propose several countermeasures, emphasizing the necessity of SSL/TLS implementation and additional verification mechanisms to protect controllers. Our findings underline the critical need to integrate security as a fundamental priority in future SDN specifications to safeguard against these threats.

Depending on the requirements of a certain engineering task, point coordinates obtained through terrestrial laser scanning (TLS) can be either in a scanner coordinate system (CS) or in the coordinate system of a geodetic control network. When point coordinates in some external CS are needed point cloud georeferencing must be done, i.e. point coordinates have to be transformed from the scanner CS into the desired CS. Different procedures can be followed during the transformation process of point coordinates from one CS to the other and consequently it can be distinguished between several types of georeferencing. The principal classification is into direct and indirect georeferencing and the main difference between the two is that direct georeferencing can (and usually does) give point coordinates in the CS of a geodetic control network instantly in the field, while indirect georeferencing inevitably needs some work to be done in the office in order to obtain these coordinates. Indire...

The paper explains the methodology and workflow for the emergency drone recording and processing applied in the Colonial Ammunition Company Shot Tower case study in Auckland, Aotearoa New Zealand. It sheds light on the strategic decisions employed during the drone scan and following data processing under significant limitations. The imperfections in data capture and processing, driven by real-world constraints, present valuable lessons for future endeavours. By capturing the intricacies of this emergency documentation process, the paper aims to contribute valuable insights and replicable workflows to the broader field of heritage preservation. The intersection of technology, urgency, and collaboration showcased in this case study opens avenues for refining methodologies, incorporating advancements, and developing standardised processes for heritage preservation in emergency scenarios.

The article illustrates the methodology and the first experimentation of the “HERIVERSO project”, which aims to create a gamification platform for the digitisation and representation of Intangible Cultural Heritage (ICH). The workflow used is defined by the study of the criteria for the conservation of intangible values. This methodology was designed to be applicable to different examples of ICH, based on the experience of the pilot case. The project also aims to test a new way of managing tangible and intangible Cultural Heritage through blockchain technology, implementing a heritage management system that will work by tokenizing digital assets to enable their reinterpretation and sale. Underlying the project is therefore the question: how to digitise ICH and use it in gamification, without distorting its meaning or losing its values, but allowing a full fruition and accessibility? The methodology used to answer this question is described using the example of the chosen case study: the Corpus Christi celebration in Valencia (Spain). To achieve these objectives, an agnostic, scalable and flexible platform for the digitisation of spaces, artifacts and instruments has been developed, composed of six technological modules. The contents must be introduced by the cultural agent and are based on two essential elements for the functioning of the system: the geolocation of ICH in the territory and the geolocation of digital content and gamification dynamics within real environments. In addition, the use of NFTs ensure the authenticity of the intangible asset and facilitating the generation of economic benefits for it.

Extraction of plot-level field measurements entails a rigid and time-consuming task. Fine resolution remote sensing technology offers an objective and consistent method for estimation of forest vertical structures. We explored the development of algorithms for estimating above ground biomass (AGB) at the plot level using terrestrial LiDAR system (TLS). This research follows IPCC Tier 2 approach, by combining field and remote sensing data, in estimating forest carbon stocks. Permanent plots (30 × 30 m diameter) were established inside Mt. Apo Natural Park. Forest inventory was conducted in July 2013, recording tree heights and stem diameters for all hardwood species with diameter at breast height (DBH) ≥ 5 cm in three management zones: multiple use, strict protection, and restoration. Quadratic mean stem diameter was employed for large DBH intervals for deriving midpoint biomass. Three tropical allometric equations were used to derive referenced biomass values. Regressions results sh...

This article illustrates the urban fabric of Ghadames (Libya), the ancient Cydamus in the Roman period. This oasis-town constituted the object of study of the "Italian Architectural Mission for the Islamic Period", founded and directed from 1989 to 1995 by Paolo Cuneo, Professor at the L'Aquila University. In this type of fabric, a splendid example of the pre-Saharan habitat of the Libyan Fezzan, the traditional collective institutions of Islamic Maghreb (jami, zawiya, marabut) are connected by a system of public spaces (majlis) and covered streets, illuminated from above through light-wells, which provide a perfect climatic control in hot arid zones. The recent work of the Mission which has been taken on by Ludovico Micara, Professor at the "G. D'Annunzio" University of Chieti-Pescara, from 1996 to 2006, faced the analysis, the study and survey of the residential fabric of Ghadames. This fabric results from the aggregation of a particular

Reliable and up-to-date road network information is crucial to guarantee efficient logistic distribution, emergency response, urban planning, etc. Road networks in developing urban areas tend to change rapidly. Periodic remapping is necessary to maintain the temporal quality of the road network information. Updating the road network using conventional methods can be a tedious task. This paper presents a methodology to extract road network automatically from an airborne LiDAR point cloud combined with color information from an aerial orthophoto. First, ground points are separated from non-ground points. We then classify the filtered ground points to road and non-road points using the Random Forest (RF) algorithm. Parallel thinning, method for skeletonization of the road segment, is carried out on a binary image extracted by a so-called density map of the classified road points. Finally, road centerline is obtained by our proposed topological order and regularization approach. The pro...

When monitoring deformations in natural hazards such as rockfalls and landslides, the use of 3D models has become a standard. Several geomatic techniques allow the generation of these models. However, each one has its pros and cons regarding accuracy, cost, sample frequency, etc. In this contribution a fixed-location time lapse camera system for continuous rockfall monitoring using photogrammetry has been developed as an alternative to Light Detection and Ranging (LiDAR) and ground-based interferometric synthetic-aperture radar (GB-InSAR). The usage of stereo photogrammetry allows the obtention of 3D points clouds at a low cost and with a high sample frequency, essential to detect premonitory displacements. In this work the designed system consists of three digital single-lens reflex (DSLR) cameras which collect photographs of the rock slope daily controlled by a Raspberry Pi computer using the open-source library gPhoto2. Photographs are automatically uploaded to a server using 3G ...

Artykuł przedstawia możliwości wykorzystania trójwymiarowego systemu wizyjnego w procesie budowy obrazu 3D produktu prowadzonym bezpośrednio na linii technologicznej np. w zakładach wytwarzających elementy pneumatyki lub hydrauliki. W pracy prezentowana jest metoda doboru odpowiedniej geometrii systemu, w skład którego wchodzi kamera i oświetlenie laserowe. Omówiono metodę pobierania profili wysokości i budowy na ich podstawie obrazu 3D produktu. Szczegółowo prezentowany jest wpływ doboru geometrii na rozdzielczość systemu wizyjnego. W pracy prezentowana jest również metoda obróbki obrazu umożliwiająca tworzenie profilu wysokości tj. przekroju produktu.

mass function of the brown dwarfs/giant planets, we need to conduct more comprehensive surveys for both types of (isolated and companion) ELL-YSOs. It is also important (26) to fill the gap between the very young brown dwarfs at several hundred astronomical units from their companions described in this paper and the close (0.5 to 10 astronomical units) extrasolar giant planets and brown dwarfs around nearby stars recently discovered (27). is the reason why we use the J-band and why we can discriminate YSOs from normal stars on the J-H versus H-K diagram. 12. The reddening corrections for the sources detected in this paper range from visual extinction of 0 to 10 magnitudes in Taurus and from 5 to 20 magnitudes in Chamaeleon. These values are consistent with the cloud extinction derived from C 18 O observations.

Cosmogenic chlorine-36 reveals dates of the multiple prehistoric earthquakes that have produced a scarp on the Hebgen Lake fault. Apparent chlorine-36 ages are stratigraphically correct, follow a predicted theoretical pattern, and produce geologically reasonable model ages of 24, 20, 7.0, 2.6, 1.7, and 0.4 thousand years ago. This result demonstrates the feasibility of using cosmogenic chlorine-36 to extract paleoearthquake records from bedrock fault scarps.

Casuarina equisetifolia L., commonly known as the Casuarina or Australian Pine, is a fast growing, evergreen tree native to the coastal regions of Southeast Asia, Australia, and the Pacific Islands  and can be useful in carbon sequestration and in afforestation programme in tropical forest. An experiment was laid out at Tropical Forest Research Institute, Jabalpur (M.P.) India with an aim to assess the growth performance of Casuarina equsetifolia clones namely IFGTB CH-1, IFGTB CH-2, IFGTB CH-3, IFGTB CH-4, IFGTB CH-5, IFGTB CH-6, IFGTB CH-7, IFGTB CH-9, IFGTB CH-10 in tropical region of Madhya Pradesh comes under Kaymore plateau and Satpura Hills agroclimatic zone of  the state.  The results revealed that the clone IFGTB CH-5 produced the maximum volume per m3 followed by the Clone IFGTB CH-2 and IFGTB CH-4 because of the highest survival percentage among the all clones and maximum carbon stock was found in clone IFGTB CH-5 (0.044 tonnes) followed by CH-2 (0.028 tonnes), CH- 4 (0.0...

LiDAR is one of the fast growing remote sensing techniques. Terrestrial laser Scanner (TLS) provides precise information about forest inventory in the form of 3D point cloud. An approach to extract tree parameters: diameter at breast height (dbh) tree height and stem length followed by volume estimation has been discussed here. The area selected for the study is Barkot Forest Range in Dehradun district of Uttarakhand. The main tree species in this region are Shorea robusta (Sal), Tectona grandis (Teak), Mallotus philippensis (Indian Red Wood) and Terminalia alata (Saj). Scans were collected using Riegl vz-400 laser scanner. Ground measurements were also recorded which included tree height and diameter at breast height (dbh). Both field measurements and TLS based computations showed excellent correlation. Forest Survey of India (FSI) in 1996 published site and species specific volumetric equations using dbh. However, three parameters: dbh, stem length and form factor have been considered in the present study. The comparative study shows excellent match between ground based measurements and TLS derived height and dbh parameters with R2 value of 0.96 and 0.98 respectively. Moreover, in respect to volume estimation, excellent correlation of 0.98 and 0.97 was achieved between the two approaches for Sal and Teak respectively. However, for Indian Red Wood, one of the estimations using FSI equation showed negative value but the present approach produced no such anomalous outcome. The reason may be attributed to the fact that FSI based volumetric equation valid only for Assam was used due to the unavailability of Barkot specific equation. Finally, volumetric equation was developed for Terminalia alata (Saj) as there is no equation available for this particular species. The study also advocates an inverse relationship between Form Factor and dbh. This new approach may prove to be indispensable for species and site specific volume estimation in near future.

Casuarina equisetifolia L., commonly known as the Casuarina or Australian Pine, is a fast growing, evergreen tree native to the coastal regions of Southeast Asia, Australia, and the Pacific Islands  and can be useful in carbon sequestration and in afforestation programme in tropical forest. An experiment was laid out at Tropical Forest Research Institute, Jabalpur (M.P.) India with an aim to assess the growth performance of Casuarina equsetifolia clones namely IFGTB CH-1, IFGTB CH-2, IFGTB CH-3, IFGTB CH-4, IFGTB CH-5, IFGTB CH-6, IFGTB CH-7, IFGTB CH-9, IFGTB CH-10 in tropical region of Madhya Pradesh comes under Kaymore plateau and Satpura Hills agroclimatic zone of  the state.  The results revealed that the clone IFGTB CH-5 produced the maximum volume per m3 followed by the Clone IFGTB CH-2 and IFGTB CH-4 because of the highest survival percentage among the all clones and maximum carbon stock was found in clone IFGTB CH-5 (0.044 tonnes) followed by CH-2 (0.028 tonnes), CH- 4 (0.0...

Highlights: We compare Plant Area Density (PAD) profiles derived from Terrestrial Laser Scanning (TLS) and contemporaneous Aerial Laser Scanning (ALS) in dense tropical forest. Poor sampling of the lower part of the canopy profile by ALS is mitigated by using a multiple resolution approach. Anisotropy of transmittance revealed by TLS allows further improvement of PAD estimates.

When monitoring deformations in natural hazards such as rockfalls and landslides, the use of 3D models has become a standard. Several geomatic techniques allow the generation of these models. However, each one has its pros and cons regarding accuracy, cost, sample frequency, etc. In this contribution a fixed-location time lapse camera system for continuous rockfall monitoring using photogrammetry has been developed as an alternative to Light Detection and Ranging (LiDAR) and ground-based interferometric synthetic-aperture radar (GB-InSAR). The usage of stereo photogrammetry allows the obtention of 3D points clouds at a low cost and with a high sample frequency, essential to detect premonitory displacements. In this work the designed system consists of three digital single-lens reflex (DSLR) cameras which collect photographs of the rock slope daily controlled by a Raspberry Pi computer using the open-source library gPhoto2. Photographs are automatically uploaded to a server using 3G network for processing. This system was implemented at Castellfollit de la Roca village (Girona province, Spain), which sits on a basaltic cliff that has shown significant rockfall intensity in recent years. The 3D models obtained will allow monitoring rockfalls frequency, premonitory displacements, and calculate the erosion rate of the slope. All technical decisions taken for the design and implementation on this specific site are discussed and first results shown.

Forests have a vital role in maintaining global climate stability by removing greenhouse gases like carbon dioxide from environment. Estimation of carbon stock is crucial in quantifying the amount of carbon that is present in the forest. The estimation of forest biomass and carbon stock through field measurements is a challenging and timeconsuming task. Here in this scenario, our study aims to estimate carbon stock in a forest area using the hybrid technique i.e., aerial survey and ground survey. We used low-altitude remote sensing data acquired by UAV to estimate biomass and carbon stock in an efficient way compared to the traditional techniques. We developed an orthomosaic from the collected aerial imageries and manually delineated tree crowns to obtain crown projection area (CPA) for the entire study area using GIS tools. Our study area contained a mixed species with Pinus Wallichiana to be the dominant species while other species are negligible. Using field-measured tree height and diameter at breast height (DBH) as input, we estimated above-ground biomass (AGB) with an allometric equation and then used a factor value to estimate carbon stock or aboveground carbon (AGC) for six sample plots. Next, we developed a relationship between CPA and carbon stock and validated it by comparing the carbon stock values obtained from the allometric equation for the remaining four sample plots. Among the various developed model, 4th order Polynomial model was chosen due to its highest coefficient of correlation. After the model validation was done the AGC of whole study area was obtained by using the CPA delineated manually from the orthomosaic image. The total AGC and AGB obtained for our study area which was about 7 hectare was 210.7480 tons and 448.4 tons respectively.

Resumen: El 3 de diciembre de 2013 ocurrió en el área de estudio piloto del escarpe de Puigcercós (Lleida, Catalunya) el mayor desprendimiento de todos los que se habían detectado desde el inicio del monitoreo LiDAR que se lleva a cabo desde noviembre de 2007. Dicho desprendimiento, de 1093 m 3 de volumen, se caracterizó por la caída conjunta de cuatro áreas afectadas por roturas del tipo vuelco. En el presente trabajo se evalúa el uso de la evolución de los ángulos de dichos vuelcos para la predicción temporal de los desprendimientos de rocas afectados por este tipo de rotura. Así, se ha podido estimar un intervalo de días en los que el desprendimiento era más probable para tres de las cuatro áreas desprendidas, y que coinciden con el día del desprendimiento. Además se concluye, que en este tipo de movimientos, el uso de los datos de ángulos son más fiables para la predicción temporal que los datos de desplazamientos superficiales.

Terrestrial laser scanning (TLS) is one of the most promising surveying techniques for rockslope characterization and monitoring. Landslide and rockfall movements can be detected by means of comparison of sequential scans. One of the most pressing challenges of natural hazards is combined temporal and spatial prediction of rockfall. An outdoor experiment was performed to ascertain whether the TLS instrumental error is small enough to enable detection of precursory displacements of millimetric magnitude. This consists of a known displacement of three objects relative to a stable surface. Results show that millimetric changes cannot be detected by the analysis of the unprocessed datasets. Displacement measurement are improved considerably by applying Nearest Neighbour (NN) averaging, which reduces the error (1σ) up to a factor of 6. This technique was applied to displacements prior to the April 2007 rockfall event at Castellfollit de la Roca, Spain. The maximum precursory displacement measured was 45 mm, approximately 2.5 times the standard deviation of the model comparison, hampering the distinction between actual displacement and instrumental error using conventional methodologies. Encouragingly, the precursory displacement was clearly detected by applying the NN averaging method. These results show that millimetric displacements prior to failure can be detected using TLS.

A detailed analysis of the pre-failure behavior of the 3 December 2013 rockfall (1,012 m 3) occurred on Puigcercós pilot study area (Catalonia, Spain) is presented. The exact date of failure was obtained based on a photographic monitoring performed every 4 h. The long-term monitoring (2,217 days) of the rock slope carried out by a Terrestrial LiDAR allowed the early detection of both pre-failure deformation and precursory rockfalls preceding the final failure. By means of the analysis of the pre-failure deformation, four different deformed areas were detected and the tertiary creep phase was observed in three of them. An attempt to predict the time to failure was performed using the Fukuzono's (1985) method. Furthermore, the temporal evolution of the precursory rockfalls occurred in those four areas during the progressive failure showed a close resemblance with the exponential pattern of the cumulated displacements at tertiary creep stage. Finally, the study of the meteorological conditions did not show any single triggering factor associated with the final failure. Reversely, the increase in the occurrence of precursory rockfalls on several areas of the slope together with the observed acceleration on the deformation pattern reinforce the role of a progressive degradation of the stability conditions, which ultimately leaded to the 3 December rockfall event.

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On 20 February 2010, an extreme rainfall episode occurred on Madeira Island, which caused an exceptionally strong flash flood and several soil slip-debris flows, producing 45 confirmed deaths and 6 persons declared missing, as well as extensive material damages. In order to understand and quantify the importance of landsliding in routing sediment through mountainous drainage, such as Madeira Island's landscape, it was essential to perform extensive landslide analysis. This study describes the methodology used to semi-automatically detect the landslides, produce the landslide inventory maps and estimate the sediment volume produced during this particular event which ranged from 217 000 m 3 to 344 000 m 3 and 605 000 m 3 to 984 000 m 3 for the Funchal and Ribeira Brava basins, respectively. These results contributed to the design and implementation of measures to prevent damages caused by landslides in Madeira Island.

This manuscript focuses on developing a workflow for determining the productivity of vineyards in a novel and innovative way, ensuring flexibility and simplicity in data acquisition, automation in the process and high-quality results, using low cost sensors. The non-invasive system proposed allows the determination of yield at cluster level by combining close-range photogrammetry and computer vision. Bunches are reconstructed in 3D from images processed with Photogrammetry Workbench software (PW) developed by the authors. Algorithms and techniques were combined to estimate the most relevant parameters in the productivity of a vineyard: volume, mass and number of berries per bunch. To validate the workflow proposed, a sample of laboratory tests based on dimensional analysis of the clusters together with the single count of berries, were analyzed to establish the groundtruth. The results achieved from the scaled models and different estimation parameters were contrasted. The results confirm the feasibility of the proposed methodology, providing scalability to a comprehensive analysis of the productivity of the vineyard and affording a constant operational improvement and proactive management.

Reliable and up-to-date road network information is crucial to guarantee efficient logistic distribution, emergency response, urban planning, etc. Road networks in developing urban areas tend to change rapidly. Periodic remapping is necessary to maintain the temporal quality of the road network information. Updating the road network using conventional methods can be a tedious task. This paper presents a methodology to extract road network automatically from an airborne LiDAR point cloud combined with color information from an aerial orthophoto. First, ground points are separated from non-ground points. We then classify the filtered ground points to road and non-road points using the Random Forest (RF) algorithm. Parallel thinning, method for skeletonization of the road segment, is carried out on a binary image extracted by a so-called density map of the classified road points. Finally, road centerline is obtained by our proposed topological order and regularization approach. The pro...

Automatic building extraction and delineation from airborne LiDAR point cloud data of urban environments is still a challenging task due to the variety and complexity at which buildings appear. The Medial Axis Transform (MAT) is able to describe the geometric shape and topology of an object, but has never been applied for building roof outline extraction. It represents the shape of an object by its centerline, or skeleton structure instead of its boundary. Notably, end points of the MAT in principle coincide with corner points of building outlines. However, the MAT is sensitive to small boundary irregularities, which makes shape detection in airborne point clouds challenging. We propose a robust MAT-based method for detecting building corner points, which are then connected to form a building boundary polygon. First, we approximate the 2D MAT of a set of building edge points acquired by the alpha-shape algorithm to derive a so-called building roof skeleton. We then propose a hierarchical corner-aware segmentation to cluster skeleton points based on their properties which are the so-called separation angle, radius of the maximally inscribe circle, and defining edge point indices. From each segment, a corner point is then estimated by extrapolating the position of the zero radius inscribed circle based on the skeleton point positions within the segment. Our experiment uses point cloud datasets of Makassar, Indonesia and EYE-Amsterdam, The Netherlands. The average positional accuracy of the building outline results for Makassar and EYE-Amsterdam is 65 cm and 70 cm, respectively, which meet one-meter base map accuracy criteria. The results imply that skeletonization is a promising tool to extract relevant geometric information on e.g. building outlines even from far from perfect geographical point cloud data.

As the amount of spatial data is growing, there is increased interest in developing tools to explore, visualize and interpret them, with the final aim of informing decision making efficiently. Within the European MIAVITA project, we examined this issue in the case of volcanic areas, where existing geospatial databases are particularly complex due to the number of threats to be considered, including volcanic (e.g. lava flows, ash fall) and non-volcanic hazards, such as landslides or tsunamis. We involved a group of hazard and risk analysts and managers, civil security officers, GIS analysts and system developers to design a Web-based geographical information system (WebGIS). We tested the system at the Mount Cameroon volcano, taking advantage of a complex hazard and risk geographical database. This study enabled identifying key requirements for such tools in volcanic areas, such as the need to manage user privileges differently according to their profile and the status of the volcano...

Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been made in order to develop a procedure for the paleoseismological analysis of bedrock fault scarps. The CF fault has been responsible for the formation of an impressive limestone fault scarp. Geomorphologic work on the CF basin and related fault indicated that the scarp originated from tectonic fault displacements. Three morphologic units have been distinguished along the fault scarp and defined as morphosome M1 (lowest part of the scarp), M2 and M3 (the uppermost part). These units display different karstic features, which are the result of their different duration of exposure to weathering. Micromorphologic analyses focused on the morphosome M1, along which the CF fault plane is exposed for a height ranging between 4 and 7 m. These analyses were aimed at defining differently weathered bands located at various heights, and parallel to the fault scarp top and base. The presence of these bands suggests repeated fault movements. The exposed fault surface displays a low-grade biokarstic weathering due to the action of epilithic and endolithic organisms. The biokarst distribution is, however, inhomogeneous and conditioned by the presence of nourishing elements, moisture and by light intensity. An area preferentially affected by the biokarstic processes develops as a band at the bedrock -soil contact at the base of the scarp. Roughness and colour analyses were made to identify uplifted bands which previously formed at the bedrock -soil contact. The roughness analysis was made using a microroughness-meter along 20-cm long horizontal transects repeated each 20 cm of fault height for the entire morphosome M1, at various sites along the scarp. The roughness variance data, plotted vs. the fault height, failed to identify differently weathered bands of paleoseismological interest. This result is probably due to the complex distribution of biokarst along the investigated fault plane. More reliable results have been obtained by areal analysis of the variation of the colour rendering of the rocks exposed along the fault plane at different sites. Photographic images of large portions of fault surfaces have been processed with standard graphic computer programs. The variations of colour indicated the presence of bands at various heights along the fault plane. Two uplifted bands have been recognised at all the investigated sites suggesting two displacement events (E1 and E2). A preliminary chronological framework for these two events, the youngest of which affected

The use of active remote sensing techniques based on light detection and ranging (LiDAR) was investigated here to estimate the green area index (GAI) of wheat crops. Emphasis was put on the maximum GAI development stage when saturation effects are known to limit the performances of standard indirect methods based either on the gap fraction or reflectance measurements. The LiDAR provides both the three dimensional (3D) point cloud from which the vertical distribution (Z profile) of the interception points is computed, as well as the intensity of the returned signal from which the green fraction (GF) is derived. The data were interpreted by exploiting the 3D ADEL-Wheat model that synthesizes the knowledge accumulated on wheat canopy structure. A LiDAR simulator that accounts for the specific observation configuration used was developed to mimic the actual LiDAR measurements. The in-silico experiments were conducted to generate training and validation dataset. Neural network were then used to estimate GAI from the Z profile and GF derived from the LiDAR measurements. Performances of GAI estimates by the several methods investigated were evaluated using either experimental data with 3 < GAI < 6 and data simulated with the 3D structure model with 1 < GAI < 7. Results confirm that using only the GF provides poor estimates of GAI (0.89 < RMSE < 1.28; 0.22 < rRMSE < 0.31), regardless of turbid medium or realistic assumptions on canopy 3D structure. The introduction of the Z profile information improved significantly the GAI estimation accuracy (0.48 < RMSE < 0.55; 0.12 < rRMSE < 0.13). This study demonstrates the interest of using the third dimension provided by LiDAR to better estimate GAI in crops under high GAI values. However, this requires the use of a realistic 3D structure crop model over which the LiDAR data could be simulated under the observational configuration used.

This paper provides a research approach and develops a methodology that helps natural weathered bedrock fault scarps to be understood in terms of their structural changes and backscatter behaviour when using terrestrial laser scanning (t-LiDAR). We tested our approach on the Pisia fault in Greece that ruptured during the 1981 Alkyonides earthquake sequence in Corinth Gulf. The method describes how to correlate fault geometry and structural variations with the backscatter signal of t-LiDAR data from naturally exhumed bedrock fault scarps. Using this method we are able to reconstruct the past slip history. We used t-LiDAR for the analysis of the monochromatic laser beam's backscattered signal to define unsupervised classes of unknown objects on fault surface. Seven classes were created based on the dendrogram technique using the maximum likelihood method. These were used to determine their spatial distribution throughout the scarp height and to calculate the terrain ruggedness index (TRI) in the defined classes. The combination of these results shows that: (i) the ruggedness increases with the scarp height and (ii) the ruggedness and backscattering describe different fault plane conditions. We found evidence for past earthquakes on the Pisia fault at our study site with average displacements in the range of 30-60 cm with corresponding magnitudes of 6.4-6.6 ± 0.1 M S. These results help to reconstruct the recent fault history and potential palaeo-events, and can also be used: i) to detect appropriate sample sites on the fault plane for absolute dating and ii) as an independent constraint on tracing slip events, assisting absolute dating techniques. This method can significantly reduce the sampling requirements and costs of cosmogenic absolute dating techniques. Overall, it might be a valuable tool for extracting data regarding the faulting history and slip events for defining seismic hazard parameters.

Landslide mapping to analyse earthquake environmental effects in Carmona, Spain-relation to the 1504 event?): The 1504 Carmona earthquake (intensity IX EMS) claimed the loss of human life and caused a number of Earthquake Environmental Effects. On the basis of historical data reported by George Bonsor (1918) this study is intended to estimate coseismic slope performance. The aim is to combine field investigations, geotechnical parameters and computerized models to generate digital probabilistic seismic landslide hazard maps on a local scale. GIS-based simulations of mass movements driven by hydrodynamical and gravitational processes are performed by means of the factor of safety, which is calculated for dry and fully water saturated conditions. Following Newmark´s sliding block model these approaches are extended to assess the potential of earthquake-triggered slope movements. Assuming a Peak Ground Acceleration of 0.3 g, representing the 1504 event, the most affected areas show a failure probability of 33.5 %.

LiDAR is one of the fast growing remote sensing techniques. Terrestrial laser Scanner (TLS) provides precise information about forest inventory in the form of 3D point cloud. An approach to extract tree parameters: diameter at breast height (dbh) tree height and stem length followed by volume estimation has been discussed here. The area selected for the study is Barkot Forest Range in Dehradun district of Uttarakhand. The main tree species in this region are Shorea robusta (Sal), Tectona grandis (Teak), Mallotus philippensis (Indian Red Wood) and Terminalia alata (Saj). Scans were collected using Riegl vz-400 laser scanner. Ground measurements were also recorded which included tree height and diameter at breast height (dbh). Both field measurements and TLS based computations showed excellent correlation. Forest Survey of India (FSI) in 1996 published site and species specific volumetric equations using dbh. However, three parameters: dbh, stem length and form factor have been considered in the present study. The comparative study shows excellent match between ground based measurements and TLS derived height and dbh parameters with R2 value of 0.96 and 0.98 respectively. Moreover, in respect to volume estimation, excellent correlation of 0.98 and 0.97 was achieved between the two approaches for Sal and Teak respectively. However, for Indian Red Wood, one of the estimations using FSI equation showed negative value but the present approach produced no such anomalous outcome. The reason may be attributed to the fact that FSI based volumetric equation valid only for Assam was used due to the unavailability of Barkot specific equation. Finally, volumetric equation was developed for Terminalia alata (Saj) as there is no equation available for this particular species. The study also advocates an inverse relationship between Form Factor and dbh. This new approach may prove to be indispensable for species and site specific volume estimation in near future.

Morphologic investigations along the Campo Felice (CF) fault (central Apennines, Italy) have been made in order to develop a procedure for the paleoseismological analysis of bedrock fault scarps. The CF fault has been responsible for the formation of an impressive limestone fault scarp. Geomorphologic work on the CF basin and related fault indicated that the scarp originated from tectonic fault displacements. Three morphologic units have been distinguished along the fault scarp and defined as morphosome M1 (lowest part of the scarp), M2 and M3 (the uppermost part). These units display different karstic features, which are the result of their different duration of exposure to weathering. Micromorphologic analyses focused on the morphosome M1, along which the CF fault plane is exposed for a height ranging between 4 and 7 m. These analyses were aimed at defining differently weathered bands located at various heights, and parallel to the fault scarp top and base. The presence of these bands suggests repeated fault movements. The exposed fault surface displays a low-grade biokarstic weathering due to the action of epilithic and endolithic organisms. The biokarst distribution is, however, inhomogeneous and conditioned by the presence of nourishing elements, moisture and by light intensity. An area preferentially affected by the biokarstic processes develops as a band at the bedrock-soil contact at the base of the scarp. Roughness and colour analyses were made to identify uplifted bands which previously formed at the bedrock-soil contact. The roughness analysis was made using a microroughness-meter along 20-cm long horizontal transects repeated each 20 cm of fault height for the entire morphosome M1, at various sites along the scarp. The roughness variance data, plotted vs. the fault height, failed to identify differently weathered bands of paleoseismological interest. This result is probably due to the complex distribution of biokarst along the investigated fault plane. More reliable results have been obtained by areal analysis of the variation of the colour rendering of the rocks exposed along the fault plane at different sites. Photographic images of large portions of fault surfaces have been processed with standard graphic computer programs. The variations of colour indicated the presence of bands at various heights along the fault plane. Two uplifted bands have been recognised at all the investigated sites suggesting two displacement events (E1 and E2). A preliminary chronological framework for these two events, the youngest of which affected