bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic and environmental determinants of the urea level in cow's milk
Authors: Czajkowska A. , Sitkowska B. , Piwczyński D. , Wójcik P. , Mroczkowski S.
Published: March 2015

Abstract. This study was conducted on a sample of 2237 Polish Holstein-Friesian cows. The aim was to estimate the effect of selected environmental factors on the level of urea in cow's milk and on its genetic parameters, i.e. the heritability coefficients, and genetic correlation with other selected traits of milk production. The present study has revealed the existence of a highly significant influence of herd, year of calving, parity, lactation phase, and milk performance level on the urea content in cow's milk. A high urea level in milk was detected in samples collected from older animals, both during the winter season and the middle phase of lactation (101–200 days). The heritability estimates were generally at a low level, particularly in terms of milk yield (0.183) and urea content (0.152–0.159), which may indicate the dominant role of the environment in shaping them. Relatively low values of genetic correlation (−0.097–0.140) between the urea content and other traits suggest that improvement of milk yield and its composition modify the urea level in milk only to a small degree.
CALIOP near-real-time backscatter products compared to EARLINET data
Authors: Grigas T. , Hervo M. , Gimmestad G. , Forrister H. , Schneider P. , Preißler J. , Tarrason L. , O'Dowd C.
Published: March 2015

Abstract. The expedited near-real-time Level 1.5 Cloud–Aerosol Lidar (Light Detection and Ranging) with Orthogonal Polarization (CALIOP) products were evaluated against data from the ground-based European Aerosol Research Lidar Network (EARLINET). Over a period of three years, lidar data from 48 CALIOP overpasses with ground tracks within a 100 km distance from an operating EARLINET station were deemed suitable for analysis and they included a valid aerosol classification type (e.g. dust, polluted dust, clean marine, clean continental, polluted continental, mixed and/or smoke/biomass burning). For the complete dataset comprising both PBL and FT data, the correlation coefficient was 0.86, and when separated into separate layers, the PBL and FT correlation coefficients were 0.6 and 0.85 respectively. The presence of FT layers with high attenuated backscatter led to poor agreement in PBL backscatter profiles between the CALIOP and EARLINET measurements and prompted a further analysis filtering out such cases. However, the correlation coefficient value for the complete dataset decreased marginally from 0.86 to 0.84 while the PBL coefficient increased from 0.6 up to 0.65 and the FT coefficient also decreased from 0.85 to 0.79. For specific aerosol types, the correlation coefficient between CALIOP backscatter profiles and ground-based lidar data ranged from 0.37 for polluted continental aerosol in the planetary boundary layer (PBL) to 0.57 for dust in the free troposphere (FT). The results suggest different levels of agreement based on the location of the dominant aerosol layer and the aerosol type.
NOx emission estimates during the 2014 Youth Olympic Games in Nanjing
Authors: Ding J. , van der A R. J. , Mijling B. , Levelt P. F. , Hao N.
Published: March 2015

Abstract. The Nanjing Government has taken temporary environmental regulations to guarantee good air quality during the Youth Olympic Games (YOG) in 2014. We study the effect of those regulations by applying the emission estimate algorithm DECSO (Daily Emission estimates Constrained by Satellite Observations) to measurements of the Ozone Monitoring Instrument (OMI). We improved DECSO by updating the chemical transport model CHIMERE from v2006 to v2013 and by adding an Observation minus Forecast (OmF) criterion to filter outlying satellite retrievals due to high aerosol concentrations. The comparison of model results with both ground and satellite observations indicates that CHIMERE v2013 is better performing than CHIMERE v2006. After filtering the satellite observations with high aerosol loads that were leading to large OmF values, unrealistic jumps in the emission estimates are removed. Despite the cloudy conditions during the YOG we could still see a decrease of tropospheric NO2 column concentrations of about 32% in the OMI observations as compared to the average NO2 concentrations from 2005 to 2012. The results of the improved DECSO algorithm for NOx emissions show a reduction of at least 25% during the YOG period. This indicates that air quality regulations taken by the local government were successful. The algorithm is also able to detect an emission reduction of 10% during the Chinese Spring Festival. This study demonstrates the capacity of the DECSO algorithm to capture the change of NOx emissions on a monthly scale. We also show that the observed concentrations and the derived emissions show different patterns that provide complimentary information. For example, the Nanjing smog episode in December 2013 led to a strong increase in NO2 concentrations without an increase in NOx emissions. Furthermore, DECSO gives us important information of the non-trivial seasonal relation between NOx emissions and NO2 concentrations on a local scale.
Atomic oxygen retrievals in the MLT region from SCIAMACHY nightglow limb measurements
Authors: Lednyts'kyy O. , von Savigny C. , Eichmann K.-U. , Mlynczak M. G.
Published: March 2015

Abstract. Vertical distributions of atomic oxygen concentration ([O]) in the mesosphere and lower thermosphere (MLT) region were retrieved from sun-synchronous SCIAMACHY/Envisat (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY on board the Environmental Satellite) limb measurements of the oxygen 557.7 nm green line emission in the terrestrial nightglow. A band pass filter was applied to eliminate contributions from other emissions, the impact of measurement noise and auroral activity. Vertical volume emission rate profiles were retrieved from integrated limb-emission rate profiles under the assumption that each atmospheric layer is horizontally homogeneous and absorption and scattering can be neglected. The radiative transfer problem was solved using regularized total least squares minimization in the inversion procedure. Atomic oxygen concentration profiles were retrieved from data collected for altitudes in the range 85–105 km with approximately 4 km vertical resolution during the time period from August 2002 to April 2012 at approximately 22:00 local time. The retrieval of [O] profiles was based on the generally accepted two-step Barth transfer scheme including consideration of quenching processes and the use of different available sources of temperature and atmospheric density profiles. A sensitivity analysis was performed for the retrieved [O] profiles to estimate maximum uncertainties assuming independent contributions of uncertainty components. Errors in photochemical model parameters depending on temperature uncertainties and random errors of model parameters contribute less than 50% to the overall [O] retrieval error. The retrieved [O] profiles were compared with reference [O] profiles provided by SABER/TIMED (Sounding of the Atmosphere using Broadband Emission Radiometry instrument on board the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics satellite) or by the NRLMSISE-00 (Naval Research Laboratory Mass Spectrometer and Incoherent Scatter radar Extended model, year: 2000) and SD-WACCM4 (Whole Atmosphere Community Climate Model with Specified Dynamics, version 4). A comparison of the retrieved [O] profiles with the reference [O] profiles led to the conclusion that the photochemical model taking into account quenching of O(1S) by O2, O(3P), and N2 and the SABER/TIMED model as a source of temperature and density profiles are the most appropriate choices for our case. The retrieved [O] profile time series exhibits characteristic seasonal variations in agreement with satellite observations based on analysis of OH Meinel band emissions and atmospheric models. A pronounced 11-year solar cycle variation can also be identified in the retrieved atomic oxygen concentration time series.
High temporal resolution estimates of columnar aerosol microphysical parameters from spectrum of aerosol optical depth by Linear Estimation: application to long-term AERONET and Star-photometry measurements
Authors: Pérez-Ramírez D. , Veselovskii I. , Whiteman D. N. , Suvorina A. , Korenskiy M. , Kolgotin A. , Holben B. , Dubovik O. , Siniuk A. , Alados-Arboledas L.
Published: March 2015

Abstract. This work deals with the applicability of the Linear Estimation technique (LE) to invert spectral measurements of aerosol optical depth (AOD) provided by AERONET CIMEL sun-photometers. The inversion of particle properties using only direct sun AODs allows the evaluation of parameters such as effective radius (reff) and columnar volume aerosol content (V) with significantly better temporal resolution than the operational AERONET algorithm which requires both direct sun and sky radiance measurements. Sensitivity studies performed demonstrate that the constraints on the range of the inversion are very important to minimize the uncertainties, and therefore estimates of reff can be obtained with uncertainties less than 30% and of V with uncertainties below 40%. The LE technique is applied to data acquired at five AERONET sites influenced by different aerosol types and the retrievals are compared with the results of the operational AERONET code. Good agreement between the two techniques is obtained when the fine mode predominates, while for coarse mode cases the LE results systematically underestimate both reff and V. The highest differences are found for cases where no mode predominates. To minimize these biases, correction functions are developed using the multi-year database of observations at selected sites, where the AERONET retrieval is used as the reference. The derived corrections are tested using data from 18 other AERONET stations offering a range of aerosol types. After correction, the LE retrievals provide better agreement with AERONET for all the sites considered. Finally, the LE approach developed here is applied to AERONET and star-photometry measurements at the city of Granada (Spain) to obtain day-to-night time-evolution of columnar aerosol microphysical properties.
Evaluation of coral reef carbonate production models at a global scale
Authors: Jones N. S. , Ridgwell A. , Hendy E. J.
Published: March 2015

Abstract. Calcification by coral reef communities is estimated to account for half of all carbonate produced in shallow water environments and more than 25% of the total carbonate buried in marine sediments globally. Production of calcium carbonate by coral reefs is therefore an important component of the global carbon cycle; it is also threatened by future global warming and other global change pressures. Numerical models of reefal carbonate production are needed for understanding how carbonate deposition responds to environmental conditions including atmospheric CO2 concentrations in the past and into the future. However, before any projections can be made, the basic test is to establish model skill in recreating present-day calcification rates. Here we evaluate four published model descriptions of reef carbonate production in terms of their predictive power, at both local and global scales. We also compile available global data on reef calcification to produce an independent observation-based data set for the model evaluation of carbonate budget outputs. The four calcification models are based on functions sensitive to combinations of light availability, aragonite saturation (Ωa) and temperature and were implemented within a specifically developed global framework, the Global Reef Accretion Model (GRAM). No model was able to reproduce independent rate estimates of whole-reef calcification, and the output from the temperature-only based approach was the only model to significantly correlate with coral-calcification rate observations. The absence of any predictive power for whole reef systems, even when consistent at the scale of individual corals, points to the overriding importance of coral cover estimates in the calculations. Our work highlights the need for an ecosystem modelling approach, accounting for population dynamics in terms of mortality and recruitment and hence calcifier abundance, in estimating global reef carbonate budgets. In addition, validation of reef carbonate budgets is severely hampered by limited and inconsistent methodology in reef-scale observations.
Soil redistribution and weathering controlling the fate of geochemical and physical carbon stabilization mechanisms in soils of an eroding landscape
Authors: Doetterl S. , Cornelis J.-T. , Six J. , Bodé S. , Opfergelt S. , Boeckx P. , Van Oost K.
Published: March 2015

Abstract. The role of eroding landscapes in organic carbon stabilization operating as C sinks or sources has been frequently discussed, but the underlying mechanisms are not fully understood. Our analysis aims to clarify the effects of soil redistribution on physical and biogeochemical soil organic carbon (SOC) stabilization mechanisms along a hillslope transect. The observed mineralogical differences seem partly responsible for the effectiveness of geochemical and physical SOC stabilization mechanisms as the mineral environment along the transect is highly variable and dynamic. The abundance of primary and secondary minerals and the weathering status of the investigated soils differ drastically along this transect. Extractable iron and aluminum components are generally abundant in aggregates, but show no strong correlation to SOC, indicating their importance for aggregate stability but not for SOC retention. We further show that pyrophosphate extractable soil components, especially manganese, play a role in stabilizing SOC within non-aggregated mineral fractions. The abundance of microbial residues and measured 14C ages for aggregated and non-aggregated SOC fractions demonstrate the importance of the combined effect of geochemical and physical protection to stabilize SOC after burial at the depositional site. Mineral alteration and the breakdown of aggregates limit the protection of C by minerals and within aggregates temporally. The 14C ages of buried soil indicate that C in aggregated fractions seems to be preserved more efficiently while C in non-aggregated fractions is released, allowing a re-sequestration of younger C with this fraction. Old 14C ages and at the same time high contents of microbial residues in aggregates suggest either that microorganisms feed on old carbon to build up microbial biomass or that these environments consisting of considerable amounts of old C are proper habitats for microorganisms and preserve their residues. Due to continuous soil weathering and, hence, weakening of protection mechanisms, a potential C sink through soil burial is finally temporally limited.
The role of watershed characteristics, permafrost thaw, and wildfire on dissolved organic carbon biodegradability and water chemistry in Arctic headwater streams
Authors: Larouche J. R. , Abbott B. W. , Bowden W. B. , Jones J. B.
Published: March 2015

Abstract. In the Alaskan Arctic, rapid climate change is increasing the frequency of disturbance including wildfire and permafrost collapse. These pulse disturbances may influence the delivery of dissolved organic carbon (DOC) to aquatic ecosystems, however the magnitude of these effects compared to the natural background variability of DOC at the watershed scale is not well known. We measured DOC quantity, composition, and biodegradability from 14 river and stream reaches (watershed sizes ranging from 1.5–167 km2) some of which were impacted by permafrost collapse (thermokarst) and fire. We found that region had a significant impact on quantity and biodegradability of DOC, likely driven by landscape and watershed characteristics such as lithology, soil and vegetation type, elevation, and glacial age. However, contrary to our hypothesis, we found that streams disturbed by thermokarst and fire did not contain significantly altered labile DOC fractions compared to adjacent reference waters, potentially due to rapid ecosystem recovery after fire and thermokarst as well as the limited spatial extent of thermokarst. Overall, biodegradable DOC ranged from 4 to 46% and contrary to patterns of DOC biodegradability in large Arctic rivers, seasonal variation in DOC biodegradability showed no clear pattern between sites, potentially related to stream geomorphology and position along the river network. While thermokarst and fire can alter DOC quantity and biodegradability at the scale of the feature, we conclude that tundra ecosystems are resilient to these types of disturbance.
Enhancement for bitwise identical reproducibility of Earth system modeling on the C-Coupler platform
Authors: Liu L. , Li R. , Zhang C. , Yang G. , Wang B. , Dong L.
Published: March 2015

Abstract. Reliable numerical simulation plays a critical role in climate change study. The reliability includes bitwise identical reproducibility, i.e. bitwise identical result of numerical simulation can be reproduced. It is important to Earth system modeling and has already been used intra modeling groups for the model development. However, it is rarely considered in a wider range even worldwide. To help achieve the worldwide bitwise identical reproducibility, we introduce the detailed implementations for the bitwise identical reproducibility on the Community Coupler (C-Coupler) platform, a uniform runtime software environment that configures, builds and runs the models in the same manner. Moreover, we share a series of experiences and suggestions regarding the bitwise identical reproducibility. We believe that these implementations, experiences and suggestions can be easily extended to other model software platforms and can prospectively advance the model development and scientific researches in the future.
3D POINT CLOUD MODEL COLORIZATION BY DENSE REGISTRATION OF DIGITAL IMAGES
Authors: Crombez N. , Caron G. , Mouaddib E.
Published: March 2015

Abstract. Architectural heritage is a historic and artistic property which has to be protected, preserved, restored and must be shown to the public. Modern tools like 3D laser scanners are more and more used in heritage documentation. Most of the time, the 3D laser scanner is completed by a digital camera which is used to enrich the accurate geometric informations with the scanned objects colors. However, the photometric quality of the acquired point clouds is generally rather low because of several problems presented below. We propose an accurate method for registering digital images acquired from any viewpoints on point clouds which is a crucial step for a good colorization by colors projection. We express this image-to-geometry registration as a pose estimation problem. The camera pose is computed using the entire images intensities under a photometric visual and virtual servoing (VVS) framework. The camera extrinsic and intrinsic parameters are automatically estimated. Because we estimates the intrinsic parameters we do not need any informations about the camera which took the used digital image. Finally, when the point cloud model and the digital image are correctly registered, we project the 3D model in the digital image frame and assign new colors to the visible points. The performance of the approach is proven in simulation and real experiments on indoor and outdoor datasets of the cathedral of Amiens, which highlight the success of our method, leading to point clouds with better photometric quality and resolution.
ACQUISITION AND REPRODUCTION OF SURFACE APPEARANCE IN ARCHITECTURAL ORTHOIMAGES
Authors: Martos A. , Cachero R.
Published: March 2015

Abstract. Software tools for photogrametric and multi-view stereo reconstruction are nowadays of generalized use in the digitization of architectural cultural heritage. Together with laser scanners, these are well established methods to digitize the three-dimensional geometric properties of real objects. However, the acquired photographic colour mapping of the resulting point clouds or the textured mesh cannot differentiate the proper surface appearance from the influence of the particular illumination present at the moment of the digitization. Acquisition of the actual surface appearance, separated from the existing illumination, is still a challenge for any kind of cultural heritage item, but very specially for architectural elements. Methods based on systematic sampling with commuting light patterns in a laboratory set-up are not suitable. Immovable and outdoor items are normally limited to the existing and uncontrolled natural illumination. This paper demonstrates a practical methodology for appearance acquisition, previously introduced in (Martos and Ruiz, 2013), applied here specifically for the production of re-illuminable architectural orthoimages. It is suitable for outdoor environments, where the illumination is variable and uncontrolled. In fact, naturally occurring changes in light among different images along the day are actually desired and exploited, producing an enhanced multi-layer dynamic texture that is not limited to a frozen RGB colour map. These layers contain valuable complementary information about the depth of the geometry, surface normal fine details and other illuminationdependent parameters, such as direct and indirect light and projected self-shadows, allowing an enhanced and re-illuminable ortoimage representation.
ADAPTIVE TEXTURE SYNTHESIS FOR LARGE SCALE CITY MODELING
Authors: Despine G. , Colleu T.
Published: March 2015

Abstract. Large scale city models textured with aerial images are well suited for bird-eye navigation but generally the image resolution does not allow pedestrian navigation. One solution to face this problem is to use high resolution terrestrial photos but it requires huge amount of manual work to remove occlusions. Another solution is to synthesize generic textures with a set of procedural rules and elementary patterns like bricks, roof tiles, doors and windows. This solution may give realistic textures but with no correlation to the ground truth. Instead of using pure procedural modelling we present a method to extract information from aerial images and adapt the texture synthesis to each building. We describe a workflow allowing the user to drive the information extraction and to select the appropriate texture patterns. We also emphasize the importance to organize the knowledge about elementary pattern in a texture catalogue allowing attaching physical information, semantic attributes and to execute selection requests. Roofs are processed according to the detected building material. Façades are first described in terms of principal colours, then opening positions are detected and some window features are computed. These features allow selecting the most appropriate patterns from the texture catalogue. We experimented this workflow on two samples with 20 cm and 5 cm resolution images. The roof texture synthesis and opening detection were successfully conducted on hundreds of buildings. The window characterization is still sensitive to the distortions inherent to the projection of aerial images onto the facades.
ADVANCES IN MULTI-SENSOR SCANNING AND VISUALIZATION OF COMPLEX PLANTS: THE UTMOST CASE OF A REACTOR BUILDING
Authors: Hullo J.-F. , Thibault G. , Boucheny C.
Published: March 2015

Abstract. In a context of increased maintenance operations and workers generational renewal, a nuclear owner and operator like Electricité de France (EDF) is interested in the scaling up of tools and methods of “as-built virtual reality” for larger buildings and wider audiences. However, acquisition and sharing of as-built data on a large scale (large and complex multi-floored buildings) challenge current scientific and technical capacities. In this paper, we first present a state of the art of scanning tools and methods for industrial plants with very complex architecture. Then, we introduce the inner characteristics of the multi-sensor scanning and visualization of the interior of the most complex building of a power plant: a nuclear reactor building. We introduce several developments that made possible a first complete survey of such a large building, from acquisition, processing and fusion of multiple data sources (3D laser scans, total-station survey, RGB panoramic, 2D floor plans, 3D CAD as-built models). In addition, we present the concepts of a smart application developed for the painless exploration of the whole dataset. The goal of this application is to help professionals, unfamiliar with the manipulation of such datasets, to take into account spatial constraints induced by the building complexity while preparing maintenance operations. Finally, we discuss the main feedbacks of this large experiment, the remaining issues for the generalization of such large scale surveys and the future technical and scientific challenges in the field of industrial “virtual reality”.
3D SURVEYING & MODELING OF UNDERGROUND PASSAGES IN WWI FORTIFICATIONS
Authors: Rodríguez-Gonzálvez P. , Nocerino E. , Menna F. , Minto S. , Remondino F.
Published: March 2015

Abstract. The virtual reconstruction of subterranean structures is a suitable scenario for the integration of different geomatics techniques although narrow passages, lack of light and irregular surface can arise various problems in the data acquisition as well as processing procedures. Generally the final product is a dense and detailed 3D model, whose number of triangles increases quickly according to the complexity of the object. This complexity reduces the efficient use and dissemination of the produced information therefore innovative solutions are sought. The article presents the 3D surveying and modelling of underground passages of World War I (WWI) fortifications. After the acquisition of dense point clouds by means of terrestrial scanning (TLS), a simplification and optimization workflow is performed with the aim of generating a lightweight product that keeps the maximum amount of significant information. A continuous scene representation with a 87% triangle reduction is generated, while the final precision is preserved according to a tolerance predefined by the final user. Such 3D product can be employed as basis for reconstruction, consolidation, preservation and valorisation of the WWI tunnels.
VIRTUAL MODELING FOR CITIES OF THE FUTURE. STATE-OF-THE ART AND VIRTUAL MODELING FOR CITIES OF THE FUTURE. STATE-OF-THE ART AN
Authors: Valencia J. , Muñoz-Nieto A. , Rodríguez-Gonzálvez P.
Published: March 2015

Abstract. 3D virtual modeling, visualization, dissemination and management of urban areas is one of the most exciting challenges that must face geomatics in the coming years. This paper aims to review, compare and analyze the new technologies, policies and software tools that are in progress to manage urban 3D information. It is assumed that the third dimension increases the quality of the model provided, allowing new approaches to urban planning, conservation and management of architectural and archaeological areas. Despite the fact that displaying 3D urban environments is an issue nowadays solved, there are some challenges to be faced by geomatics in the coming future. Displaying georeferenced linked information would be considered the first challenge. Another challenge to face is to improve the technical requirements if this georeferenced information must be shown in real time. Are there available software tools ready for this challenge? Are they useful to provide services required in smart cities? Throughout this paper, many practical examples that require 3D georeferenced information and linked data will be shown. Computer advances related to 3D spatial databases and software that are being developed to convert rendering virtual environment to a new enriched environment with linked information will be also analyzed. Finally, different standards that Open Geospatial Consortium has assumed and developed regarding the three-dimensional geographic information will be reviewed. Particular emphasis will be devoted on KML, LandXML, CityGML and the new IndoorGML.
TOOTEKO: A CASE STUDY OF AUGMENTED REALITY FOR AN ACCESSIBLE CULTURAL HERITAGE. DIGITIZATION, 3D PRINTING AND SENSORS FOR AN AUDIO-TACTILE EXPERIENCE
Authors: D’Agnano F. , Balletti C. , Guerra F. , Vernier P.
Published: March 2015

Abstract. Tooteko is a smart ring that allows to navigate any 3D surface with your finger tips and get in return an audio content that is relevant in relation to the part of the surface you are touching in that moment. Tooteko can be applied to any tactile surface, object or sheet. However, in a more specific domain, it wants to make traditional art venues accessible to the blind, while providing support to the reading of the work for all through the recovery of the tactile dimension in order to facilitate the experience of contact with art that is not only "under glass." The system is made of three elements: a high-tech ring, a tactile surface tagged with NFC sensors, and an app for tablet or smartphone. The ring detects and reads the NFC tags and, thanks to the Tooteko app, communicates in wireless mode with the smart device. During the tactile navigation of the surface, when the finger reaches a hotspot, the ring identifies the NFC tag and activates, through the app, the audio track that is related to that specific hotspot. Thus a relevant audio content relates to each hotspot. The production process of the tactile surfaces involves scanning, digitization of data and 3D printing. The first experiment was modelled on the facade of the church of San Michele in Isola, made by Mauro Codussi in the late fifteenth century, and which marks the beginning of the Renaissance in Venice. Due to the absence of recent documentation on the church, the Correr Museum asked the Laboratorio di Fotogrammetria to provide it with the aim of setting up an exhibition about the order of the Camaldolesi, owners of the San Michele island and church. The Laboratorio has made the survey of the facade through laser scanning and UAV photogrammetry. The point clouds were the starting point for prototypation and 3D printing on different supports. The idea of the integration between a 3D printed tactile surface and sensors was born as a final thesis project at the Postgraduate Mastercourse in Digital Architecture of the University of Venice (IUAV) in 2012. Now Tooteko is now a start up company based in Venice, Italy.
ACCURACY EVALUATION OF A MOBILE MAPPING SYSTEM WITH ADVANCED STATISTICAL METHODS
Authors: Toschi I. , Rodríguez-Gonzálvez P. , Remondino F. , Minto S. , Orlandini S. , Fuller A.
Published: March 2015

Abstract. This paper discusses a methodology to evaluate the precision and the accuracy of a commercial Mobile Mapping System (MMS) with advanced statistical methods. So far, the metric potentialities of this emerging mapping technology have been studied in few papers, where generally the assumption that errors follow a normal distribution is made. In fact, this hypothesis should be carefully verified in advance, in order to test how well the Gaussian classic statistics can adapt to datasets that are usually affected by asymmetrical gross errors. The workflow adopted in this study relies on a Gaussian assessment, followed by an outlier filtering process. Finally, non-parametric statistical models are applied, in order to achieve a robust estimation of the error dispersion. Among the different MMSs available on the market, the latest solution provided by RIEGL is here tested, i.e. the VMX-450 Mobile Laser Scanning System. The test-area is the historic city centre of Trento (Italy), selected in order to assess the system performance in dealing with a challenging and historic urban scenario. Reference measures are derived from photogrammetric and Terrestrial Laser Scanning (TLS) surveys. All datasets show a large lack of symmetry that leads to the conclusion that the standard normal parameters are not adequate to assess this type of data. The use of non-normal statistics gives thus a more appropriate description of the data and yields results that meet the quoted a-priori errors.
MODELING AND ACCURACY ASSESSMENT FOR 3D-VIRTUAL RECONSTRUCTION IN CULTURAL HERITAGE USING LOW-COST PHOTOGRAMMETRY: SURVEYING OF THE “SANTA MARÍA AZOGUE” CHURCH’S FRONT
Authors: Robleda Prieto G. , Pérez Ramos A.
Published: March 2015

Abstract. Sometimes it could be difficult to represent “on paper" an architectural idea, a solution, a detail or a newly created element, depending on the complexity what it want be conveyed through its graphical representation but it may be even harder to represent the existing reality. (a building, a detail,...), at least with an acceptable degree of definition and accuracy. As a solution to this hypothetical problem, this paper try to show a methodology to collect measure data by combining different methods or techniques, to obtain the characteristic geometry of architectonic elements, especially in those highly decorated and/or complex geometry, as well as to assess the accuracy of the results obtained, but in an accuracy level enough and not very expensive costs. In addition, we can obtain a 3D recovery model that allows us a strong support, beyond point clouds obtained through another more expensive methods as using laser scanner, to obtain orthoimages. This methodology was used in the study case of the 3D-virtual reconstruction of a main medieval church façade because of the geometrical complexity in many elements as the existing main doorway with archivolts and many details, as well as the rose window located above it so it's inaccessible due to the height.
ADVANCES IN IMAGE PRE-PROCESSING TO IMPROVE AUTOMATED 3D RECONSTRUCTION
Authors: Ballabeni A. , Apollonio F. I. , Gaiani M. , Remondino F.
Published: March 2015

Abstract. Tools and algorithms for automated image processing and 3D reconstruction purposes have become more and more available, giving the possibility to process any dataset of unoriented and markerless images. Typically, dense 3D point clouds (or texture 3D polygonal models) are produced at reasonable processing time. In this paper, we evaluate how the radiometric pre-processing of image datasets (particularly in RAW format) can help in improving the performances of state-of-the-art automated image processing tools. Beside a review of common pre-processing methods, an efficient pipeline based on color enhancement, image denoising, RGB to Gray conversion and image content enrichment is presented. The performed tests, partly reported for sake of space, demonstrate how an effective image pre-processing, which considers the entire dataset in analysis, can improve the automated orientation procedure and dense 3D point cloud reconstruction, even in case of poor texture scenarios.
NON-CONTACT PHOTOGRAMMETRIC METHODOLOGY TO EVALUATE THE STRUCTURAL HEALTH OF HISTORICAL CONSTRUCTIONS
Authors: Sánchez-Aparicio L. J. , Villarino A. , García-Gago J. , González-Aguilera D.
Published: March 2015

Abstract. Accurate studies of cultural heritage structures usually require the application of combined techniques to understand its structural behaviour. It is in this context, where the article present a set of procedures based on the dual combination of photogrammetric methodologies (image-based modelling and digital image correlation) and the finite element method to understand the structural behaviour of these structures. Through the interpretation of the different obtained products, by the defined approach, it is possible to estimate and evaluate the causes of the structural damage that the analysed infrastructure can suffer and also design subsequent restoration mechanisms, always from a perspective of minimal intrusion to the structure. This case of study aims to validate the methodology presented, using as an example a case of vernacular architecture (a dome) in Sejas de Aliste (Zamora, Spain).
4D CITY TRANSFORMATIONS BY TIME SERIES OF AERIAL IMAGES
Authors: Adami A.
Published: March 2015

Abstract. Recent photogrammetric applications, based on dense image matching algorithms, allow to use not only images acquired by digital cameras, amateur or not, but also to recover the vast heritage of analogue photographs. This possibility opens up many possibilities in the use and enhancement of existing photos heritage. The research of the original figuration of old buildings, the virtual reconstruction of disappeared architectures and the study of urban development are some of the application areas that exploit the great cultural heritage of photography. Nevertheless there are some restrictions in the use of historical images for automatic reconstruction of buildings such as image quality, availability of camera parameters and ineffective geometry of image acquisition. These constrains are very hard to solve and it is difficult to discover good dataset in the case of terrestrial close range photogrammetry for the above reasons. Even the photographic archives of museums and superintendence, while retaining a wealth of documentation, have no dataset for a dense image matching approach. Compared to the vast collection of historical photos, the class of aerial photos meets both criteria stated above. In this paper historical aerial photographs are used with dense image matching algorithms to realize 3d models of a city in different years. The models can be used to study the urban development of the city and its changes through time. The application relates to the city centre of Verona, for which some time series of aerial photographs have been retrieved. The models obtained in this way allowed, right away, to observe the urban development of the city, the places of expansion and new urban areas. But a more interesting aspect emerged from the analytical comparison between models. The difference, as the Euclidean distance, between two models gives information about new buildings or demolitions. As considering accuracy it is necessary point out that the quality of final observations from model comparison depends on several aspects such as image quality, image scale and marker accuracy from cartography.
A NEW IDEA OF BIM SYSTEM FOR VISUALIZATION, WEB SHARING AND USING HUGE COMPLEX 3D MODELS FOR FACILITY MANAGEMENT.
Authors: Fassi F. , Achille C. , Mandelli A. , Rechichi F. , Parri S.
Published: March 2015

Abstract. The work is the final part of a multi-year research project on the Milan Cathedral, which focused on the complete survey and threedimensional modeling of the Great Spire (Fassi et al., 2011) and the two altars in the transept. The main purpose of the job was to prepare support data for the maintenance operations involving the cathedral since 2009 and still in progress. The research job had begun addressing our efforts to identify which methods would allow an expeditious but comprehensive measure of complex architectural structure as a whole. (Achille et al., 2012) The following research works were focused mainly to find an efficient method to visualize, use and share the realized 3D model.
FROM TLS TO HBIM. HIGH QUALITY SEMANTICALLY-AWARE 3D MODELING OF COMPLEX ARCHITECTURE
Authors: Quattrini R. , Malinverni E. S. , Clini P. , Nespeca R. , Orlietti E.
Published: March 2015

Abstract. In order to improve the framework for 3D modeling, a great challenge is to obtain the suitability of Building Information Model (BIM) platform for historical architecture. A specific challenge in HBIM is to guarantee appropriateness of geometrical accuracy. The present work demonstrates the feasibility of a whole HBIM approach for complex architectural shapes, starting from TLS point clouds. A novelty of our method is to work in a 3D environment throughout the process and to develop semantics during the construction phase. This last feature of HBIM was analyzed in the present work verifying the studied ontologies, enabling the data enrichment of the model with non-geometrical information, such as historical notes, decay or deformation evidence, decorative elements etc. The case study is the Church of Santa Maria at Portonovo, an abbey from the Romanesque period. Irregular or complex historical architecture, such as Romanesque, needs the construction of shared libraries starting from the survey of its already existing elements. This is another key aspect in delivering Building Information Modeling standards. In particular, we focus on the quality assessment of the obtained model, using an open-source sw and the point cloud as reference. The proposed work shows how it is possible to develop a high quality 3D model semantic-aware, capable of connecting geometrical-historical survey with descriptive thematic databases. In this way, a centralized HBIM will serve as comprehensive dataset of information about all disciplines, particularly for restoration and conservation. Moreover, the geometric accuracy will ensure also reliable visualization outputs.
LASER SCANNER AND CAMERA-EQUIPPED UAV ARCHITECTURAL SURVEYS
Authors: Maiellaro N. , Zonno M. , Lavalle P.
Published: March 2015

Abstract. The paper reports the workflow of 3D modelling and photorealistic texture mapping based on close range imagery acquired through a terrestrial laser scan and a camera mounted on a mini Unmanned Aerial Vehicle (UAV). The 3D models of the same architectural object – a watchtower named “Torre Pelosa” (Bari, Italy) - were compared in order to evaluate strengths and weaknesses of the used instruments and methods. The evaluated parameters where geo-referencing capability, manageability, manoeuvrability, operational constraint, survey completeness and costs. Despite a lower accuracy of the results, the use of a UAV mounted camera is essential to obtain a whole representation of the tower.
ATTEMPTS TO AUTOMATE THE PROCESS OF GENERATION OF ORTHOIMAGES OF OBJECTS OF CULTURAL HERITAGE
Authors: Markiewicz J. S. , Podlasiak P. , Zawieska D.
Published: March 2015

Abstract. At present, digital documentation recorded in the form of raster or vector files is the obligatory way of inventorying historical objects. The orthoimage is a cartometric form of photographic presentation of information in the two-dimensional reference system. The paper will discuss the issue of automation of the orthoimage generation basing on the TLS data and digital images. At present attempts are made to apply modern technologies not only for the needs of surveys, but also during the data processing. This paper will present attempts aiming at utilisation of appropriate algorithms and the author’s application for automatic generation of the projection plane, for the needs of acquisition of intensity orthoimages from the TLS data. Such planes are defined manually in the majority of popular TLS data processing applications. A separate issue related to the RGB image generation is the orientation of digital images in relation to scans. It is important, in particular in such cases when scans and photographs are not taken simultaneously. This paper will present experiments concerning the utilisation of the SIFT algorithm for automatic matching of intensity orthoimages of the intensity and digital (RGB) photographs. Satisfactory results of the process of automation, as well as in relation to the quality of resulting orthoimages have been obtained.
ASSESSING PATHOLOGIES ON VILLAMAYOR STONE (SALAMANCA, SPAIN) BY TERRESTRIAL LASER SCANNER INTENSITY DATA
Authors: García-Talegón J. , Calabrés S. , Fernández-Lozano J. , Iñigo A. C. , Herrero-Fernández H. , Arias-Pérez B. , González-Aguilera D.
Published: March 2015

Abstract. This paper deals with the assessing of pathologies in façades using a variety of intensity data provided by different terrestrial laser scanner. In particular, a complex building built in the Villamayor Stone that is to be candidate as a Global Heritage Stone Resource has been chosen as study case. The Villamayor Stone were quarrying for the construction and ornamentation of monuments in Salamanca, declared World Heritage City by UNESCO in 1988. The objective of this paper is to assess the pathologies of Villamayor Stone and compare the results obtained through the laser techniques with the classical techniques of mapped pathologies (i.e. visual inspection). For that intensity data coming from laser scanners will be used as non-destructive techniques applied to the façades and several retired plaques (after of building restoration) of Villamayor Stone with pathologies (fissures, scales, loss of matter, humidity/biological colonization) carried to the laboratory. Subsequently it will perform different comparisons between the accuracy reached with the different sensors and a high precision model setup on laboratory which performs as “ground truth”. In particular, the following objectives will be pursued: i) accuracy assessment of the results obtained in in situ and laboratory; ii) an automation or semi-automation of the detection of pathologies in Villamayor Stone; iii) discriminate the different types of Villamayor Stone used in the façades in function of the radiometric response; iv) establish a methodology for detection and assessing of pathologies based on laser scanner intensity data applied to monuments and modern buildings built in Villamayor Stone.
AERIAL MAPPING AND MULTI-SENSORS APPROACHES FROM REMOTE SENSING APPLIED TO THE ROMAN ARCHAEOLOGICAL HERITAGE
Authors: Uribe P. , Angás J. , Pérez-Cabello F. , de la Riva J. , Bea M. , Serreta A. , Magallón M. A. , Sáenz C. , Martín-Bueno M.
Published: March 2015

Abstract. This report details the preliminary results of the research focused on Roman archaeological heritage in the Middle Ebro Valley (Spain). The principal objective of this project was to obtain several different readings by means of a UAV equipped with different sensors. Firstly, it has been possible to obtain accurate maps, 3D models and digital elevation models of the site. Secondly, it has been possible to investigate and define archaeological remains still underground, via a new methodology which utilises visible and near-infrared wavelengths.
STRUCTURE FROM MOTION SYSTEMS FOR ARCHITECTURAL HERITAGE. A SURVEY OF THE INTERNAL LOGGIA COURTYARD OF PALAZZO DEI CAPITANI, ASCOLI PICENO, ITALY
Authors: Ippoliti E. , Meschini A. , Sicuranza F.
Published: March 2015

Abstract. We present the results of a point-cloud-based survey deriving from the use of image-based techniques, in particular with multi-image monoscopic digital photogrammetry systems and software, the so-called “structure-from-motion” technique. The aim is to evaluate the advantages and limitations of such procedures in architectural surveying, particularly in conditions that are “at the limit”. A particular case study was chosen: the courtyard of Palazzo dei Capitani del Popolo in Ascoli Piceno, Italy, which can be considered the ideal example due to its notable vertical, rather than horizontal, layout. In this context, by comparing and evaluating the different results, we present experimentation regarding this single case study with the aim of identifying the best workflow to realise a complex, articulated set of representations—using 3D modelling and 2D processing—necessary to correctly document the particular characteristics of such an architectural object.