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This paper presents a comparative study with different remote sensing technologies to recognize pathologies in façades of historical buildings. Building materials deteriorate over the years due to different extrinsic and intrinsic agents, so assessing these diseases in a non-invasive way is crucial to help preserve them. Most of these buildings are extremely valuable and some of them have been declared monuments of cultural interest. In this way through close range remote sensing techniques, it is possible to study material pathologies in a rigorous way and in a short duration field campaign. For the investigation two different acquisition systems were applied, active and passive methods. The terrestrial laser scanner FARO Focus 3D was used as active sensor, working at the wavelength of 905 nm. For the case of passive sensors, a Nikon D-5000 and a 6- bands Mini-MCA multispectral camera (530-801 nm) were applied covering visible and near infrared spectral range. This analysis allows assessing the sensor, or sensors combination, suitability for pathologies detection, addressing the limitations according to the spatial and spectral resolution. Moreover, the pathology detection by unsupervised classification methods is addressed in order to evaluate the automation capability of this process.

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.

The complexity of archaeological sites hinders to get an integral modelling using the actual Geomatic techniques (i.e. aerial, closerange photogrammetry and terrestrial laser scanner) individually, so a multi-sensor approach is proposed as the best solution to provide a 3D reconstruction and visualization of these complex sites. Sensor registration represents a riveting milestone when automation is required and when aerial and terrestrial dataset must be integrated. To this end, several problems must be solved: coordinate system definition, geo-referencing, co-registration of point clouds, geometric and radiometric homogeneity, etc. Last but not least, safeguarding of tangible archaeological heritage and its associated intangible expressions entails a multi-source data approach in which heterogeneous material (historical documents, drawings, archaeological techniques, habit of living, etc.) should be collected and combined with the resulting hybrid 3D of “Tolmo de Minateda” located models. The proposed multi-data source and multi-sensor approach is applied to the study case of “Tolmo de Minateda” archaeological site. A total extension of 9 ha is reconstructed, with an adapted level of detail, by an ultralight aerial platform (paratrike), an unmanned aerial vehicle, a terrestrial laser scanner and terrestrial photogrammetry. In addition, the own defensive nature of the site (i.e. with the presence of three different defensive walls) together with the considerable stratification of the archaeological site (i.e. with different archaeological surfaces and constructive typologies) require that tangible and intangible archaeological heritage expressions can be integrated with the hybrid 3D models obtained, to analyse, understand and exploit the archaeological site by different experts and heritage stakeholders.

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.

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.

One criterion for the evaluation of surface cracks in steel welds is to analyze the depth of the crack, because it is an effective indicator of its potential risk. This paper proposes a new methodology to obtain an accurate crack-depth prediction model based on the combination of infrared thermography and the 3D reconstruction procedure. In order to do this, a study of the cooling rate of the steel is implemented through active infrared thermography, allowing the study of the differential thermal behavior of the steel in the fissured zone with respect to the nonfissured zone. These cooling rate data are correlated with the real geometry of the crack, which is obtained with the 3D reconstruction of the welds through a macrophotogrammetric procedure. In this way, it is possible to analyze the correlation between cooling rate and depth through the different zones of the crack. The results of the study allow the establishment of an accurate predictive depth model which enables the study of the depth of the crack using only the cooling rate data. In this way, the remote measure of the depth of the surface steel crack based on thermography is possible.

The unmanned aerial vehicles (UAVs) are automated systems whose main characteristic is that can be remotely piloted. This property is especially interesting in those civil engineering works in which the accuracy of the model is not reachable by common aerial or satellite systems, there is a difficult accessibility to the infrastructure due to location and geometry aspects, and the economic resources are limited. This paper aims to show the research, development and application of a UAV that will generate georeferenced spatial information at low cost, high quality, and high availability. In particular, a 3D modelling and accuracy assessment of granite quarry using UAV is applied. With regard to the image-based modelling pipeline, an automatic approach supported by open source tools is performed. The process encloses the well-known image-based modelling steps: calibration, extraction and matching of features; relative and absolute orientation of images and point cloud and surface generation. Beside this, an assessment of the final model accuracy is carried out by means of terrestrial laser scanner (TLS), imaging total station (ITS) and global navigation satellite system (GNSS) in order to ensure its validity. This step follows a twofold approach: (i) firstly, using singular check points to provide a dimensional control of the model and (ii) secondly, analyzing the level of agreement between the realitybased 3D model obtained from UAV and the generated with TLS. The main goal is to establish and validate an image-based modelling workflow using UAV technology which can be applied in the surveying and monitoring of different quarries.

Abstract Background Hypertension accounts for the greatest burden of disease worldwide, yet hypertension awareness and control rates are suboptimal, especially within low- and middle-income countries. Guidelines can enable consistency of care and improve health outcomes. A small body of studies investigating clinicians’ perceptions and implementation of hypertension guidelines exists, mostly focussed on higher income settings. This study aims to explore how hypertension guidelines are used by clinicians across different resource settings, and the factors influencing their use. Methods A qualitative approach was employed using convenience sampling and in-depth semi-structured interviews. Seventeen medical doctors were interviewed over video or telephone call from March to August 2020. Two clinicians worked in low-income countries, ten in middle-income countries, and five in high-income countries. Interviews were recorded, transcribed, and coded inductively. Reflexive thematic analysis was used. Results Themes were generated at three levels at which clinicians perceived influencing factors to be operating: healthcare worker, healthcare worker interactions with patients, and the wider health system. Within each level, influencing factors were described as barriers to and facilitators of guideline use. Variation in factors occurred across income settings. At the healthcare worker level, usability of guidelines, trust in guidelines, attitudes and views about guidelines’ purpose, and relevance to patient populations were identified as themes. Influencing factors at the health system level were accessibility of equipment and medications, workforce, and access to healthcare settings. Influences at the patient level were clinician perceived patient motivation and health literacy, and access to, and cost of treatment, although these represented doctors’ perceptions rather than patient perceived factors. Conclusions This study adds a high level global view to previous studies investigating clinician perspectives on hypertension guideline use. Guidelines should be evidence-based, regularly updated and attention should be given to increasing applicability to LMICs and a range of healthcare professionals.

Abstract Background Hypertension is the largest single contributor to the global burden of disease, affecting an estimated 1.39 billion people worldwide. Clinical practice guidelines (CPGs) can aid in the effective management of this common condition, however, inconsistencies exist between CPGs, and the extent of this is unknown. Understanding the differences in CPG recommendations across income settings may provide an important means of understanding some of the global variations in clinical outcomes related to hypertension. Aims This study aims to analyse the variation between hypertension CPGs globally. It aims to assess the variation in three areas: diagnostic threshold and staging, treatment and target blood pressure (BP) recommendations in hypertension. Methods A search was conducted on the MEDLINE repository to identify national and international hypertension CPGs from 2010 to May 2020. An additional country-specific grey-literature search was conducted for all countries and territories of the world as identified by the World Bank. Data describing the diagnosis, staging, treatment and target blood pressure were extracted from CPGs, and variations between CPGs for these domains were analysed. Results Forty-eight CPGs from across all World Bank income settings were selected for analysis. Ninety-six per cent of guidelines defined hypertension as a clinic-based BP of ≥140/90 mmHg, and 87% of guidelines recommended a target BP of

Abstract Background Nowadays, automated phenotyping of plants is essential for precise and cost-effective improvement in the efficiency of crop genetics. In recent years, machine learning (ML) techniques have shown great success in the classification and modelling of crop parameters. In this research, we consider the capability of ML to perform grain yield prediction in soybeans by combining data from different optical sensors via RF (Random Forest) and XGBoost (eXtreme Gradient Boosting). During the 2018 growing season, a panel of 382 soybean recombinant inbred lines were evaluated in a yield trial at the Agronomy Center for Research and Education (ACRE) in West Lafayette (Indiana, USA). Images were acquired by the Parrot Sequoia Multispectral Sensor and the S.O.D.A. compact digital camera on board a senseFly eBee UAS (Unnamed Aircraft System) solution at R4 and early R5 growth stages. Next, a standard photogrammetric pipeline was carried out by SfM (Structure from Motion). Multispectral imagery serves to analyse the spectral response of the soybean end-member in 2D. In addition, RGB images were used to reconstruct the study area in 3D, evaluating the physiological growth dynamics per plot via height variations and crop volume estimations. As ground truth, destructive grain yield measurements were taken at the end of the growing season. Results Algorithms and feature extraction techniques were combined to develop a regression model to predict final yield from imagery, achieving an accuracy of over 90.72% by RF and 91.36% by XGBoost. Conclusions Results provide practical information for the selection of phenotypes for breeding coming from UAS data as a decision support tool, affording constant operational improvement and proactive management for high spatial precision.

BackgroundClinical practice guidelines (CPGs) aim to standardize clinical care. Increasingly, hospitals rely on locally produced guidelines alongside national guidance. This study examines variation between national and local CPGs, using the example of acute paediatric asthma guidance from the United Kingdom and the Netherlands.MethodsFifteen British and Dutch local CPGs were collected with the matching national guidance for the management of acute asthma in children under 18 years old. The drug sequences, routes and methods of administration recommended for patients with severe asthma and the tone of recommendation across both types of CPGs were schematically represented. Deviations from national guidance were measured. Variation in recommended doses of intravenous salbutamol was examined. CPG quality was assessed using the Appraisal of Guidelines for Research and Evaluation (AGREE) II.ResultsBritish and Dutch national CPGs differed in the recommended drug choices, sequences, routes and methods of administration for severe asthma. Dutch national guidance was more rigidly defined. Local British CPGs diverged from national guidance for 23% of their recommended interventions compared to 8% for Dutch local CPGs. Five British local guidelines and two Dutch local guidelines differed from national guidance for multiple treatment steps. Variation in second-line recommendations was greater than for first-line recommendations across local CPGs from both countries. Recommended starting doses for salbutamol infusions varied by more than tenfold. The quality of the sampled local CPGs was low across all AGREE II domains.ConclusionsLocal CPGs for the management of severe acute paediatric asthma featured substantial variation and frequently diverged from national guidance. Although limited to one condition, this study suggests that unmeasured variation across local CPGs may contribute to variation of care more broadly, with possible effects on healthcare quality.

Weld bead detection is essential for automated welding inspection processes. The non-invasive passive techniques, such as photogrammetry, are quickly evolving to provide a 3D point cloud with submillimeter precision and spatial resolution. However, its application in weld visual inspection has not been extensively studied. The derived 3D point clouds, despite the lack of topological information, store significant information for the weld-plaque segmentation. Although the weld bead detection is being carried out over images or based on laser profiles, its characterization by means of 3D geometrical features has not been assessed. Moreover, it is possible to combine machine learning approaches and the 3D features in order to realize the full potential of the weld bead segmentation of 3D submillimeter point clouds. In this paper, the novelty is focused on the study of 3D features on real cases to identify the most relevant ones for weld bead detection on the basis of the information gain. For this novel contribution, the influence of neighborhood size for covariance matrix computation, decision tree algorithms, and split criteria are analyzed to assess the optimal results. The classification accuracy is evaluated by the degree of agreement of the classified data by the kappa index and the area under the receiver operating characteristic (ROC) curve. The experimental results show that the proposed novel methodology performs better than 0.85 for the kappa index and better than 0.95 for ROC area.

In this paper, a novel method for the documentation and evaluation of the machine rooms in hospitals is presented. The approach is based on data acquired with a portable mobile mapping system (PMMS), GeoSlam Zeb-Revo, which has proved to be effective for three-dimensional (3D) mapping of indoor environments, as well as for 3D modeling of individual thermal and fluid-mechanics equipment. An automatic data processing workflow based on the extraction of quantitative and qualitative geometrical features from the point clouds provided by the PMMS is developed with the aim of evaluating the state and adequate distributions of machineries and, in this way, generating a complete three-dimensional map of the industrial environment to be used for maintenance, inspection, and inventory tasks in accordance with safety standards. The extracted parameters are statistically tested to evaluate the adequacy of the proposed methodology and, in this way, demonstrate its potential for the application in the context of hospital facilities.

Este artículo expone la metodología y los criterios adoptados para el desarrollo de una nueva herramienta para la gestión del Plan de Salvaguardia de los edificios históricos de Avila, ciudad española Patrimonio de la Humanidad. Como resultado de una primera aproximación hubo que tener en cuenta los siguientes requerimientos: compleción, interactividad, facilidad de uso, modularidad y bajo coste. Debido a las características de la información (espacialmente localizada, heterogenea y proporcionada en diversos formatos) consideramos indispensable la creación de un sistema de información espacial capaz de organizar todos los contenidos multimedia del Plan (imágenes 2D, imágenes panorámicas, gráficos, texto, documentos y música). Aunque el principal objetivo ha sido proporcionar una herramienta sencilla para la gestión del patrimonio histórico-artístico, los elementos de la herramienta creada abren nuevas posibilidades para otros usos en el futuro.