Quantifying the effect of aerial imagery resolution in automated hydromorphological river characterisation

Existing regulatory frameworks aiming to improve the quality of rivers place hydromorphology as a key factor in the assessment of hydrology, morphology and river continuity. The majority of available methods for hydromorphological characterisation rely on the identification of homogeneous areas (i.e., features) of flow, vegetation and substrate. For that purpose, aerial imagery is used to identify existing features through either visual observation or automated classification techniques. There is evidence to believe that the success in feature identification relies on the resolution of the imagery used. However, little effort has yet been made to quantify the uncertainty in feature identification associated with the resolution of the aerial imagery. This paper contributes to address this gap in knowledge by contrasting results in automated hydromorphological feature identification from unmanned aerial vehicles (UAV) aerial imagery captured at three resolutions (2.5 cm, 5 cm and 10 cm) along a 1.4 km river reach. The results show that resolution plays a key role in the accuracy and variety of features identified, with larger identification errors observed for riffles and side bars. This in turn has an impact on the ecological characterisation of the river reach. The research shows that UAV technology could be essential for unbiased hydromorphological assessment

Automated identification of river hydromorphological features using UAV high resolution aerial imagery

European legislation is driving the development of methods for river ecosystem protection in light of concerns over water quality and ecology. Key to their success is the accurate and rapid characterisation of physical features (i.e., hydromorphology) along the river. Image pattern recognition techniques have been successfully used for this purpose. The reliability of the methodology depends on both the quality of the aerial imagery and the pattern recognition technique used. Recent studies have proved the potential of Unmanned Aerial Vehicles (UAVs) to increase the quality of the imagery by capturing high resolution photography. Similarly, Artificial Neural Networks (ANN) have been shown to be a high precision tool for automated recognition of environmental patterns. This paper presents a UAV based framework for the identification of hydromorphological features from high resolution RGB aerial imagery using a novel classification technique based on ANNs. The framework is developed for a 1.4 km river reach along the river Dee in Wales, United Kingdom. For this purpose, a Falcon 8 octocopter was used to gather 2.5 cm resolution imagery. The results show that the accuracy of the framework is above 81%, performing particularly well at recognising vegetation. These results leverage the use of UAVs for environmental policy implementation and demonstrate the potential of ANNs and RGB imagery for high precision river monitoring and river management

Towards a transferable UAV-based framework for river hydromorphological characterization

The multiple protocols that have been developed to characterize river hydromorphology, partly in response to legislative drivers such as the European Union Water Framework Directive (EU WFD), make the comparison of results obtained in different countries challenging. Recent studies have analyzed the comparability of existing methods, with remote sensing based approaches being proposed as a potential means of harmonizing hydromorphological characterization protocols. However, the resolution achieved by remote sensing products may not be sufficient to assess some of the key hydromorphological features that are required to allow an accurate characterization. Methodologies based on high resolution aerial photography taken from Unmanned Aerial Vehicles (UAVs) have been proposed by several authors as potential approaches to overcome these limitations. Here, we explore the applicability of an existing UAV based framework for hydromorphological characterization to three different fluvial settings representing some of the distinct ecoregions defined by the WFD geographical intercalibration groups (GIGs). The framework is based on the automated recognition of hydromorphological features via tested and validated Artificial Neural Networks (ANNs). Results show that the framework is transferable to the Central-Baltic and Mediterranean GIGs with accuracies in feature identification above 70%. Accuracies of 50% are achieved when the framework is implemented in the Very Large Rivers GIG. The framework successfully identified vegetation, deep water, shallow water, riffles, side bars and shadows for the majority of the reaches. However, further algorithm development is required to ensure a wider range of features (e.g., chutes, structures and erosion) are accurately identified. This study also highlights the need to develop an objective and fit for purpose hydromorphological characterization framework to be adopted within all EU member states to facilitate comparison of results

Investigaciones sobre paz, conflictos y violencia en México

En cumplimiento a la normatividad sobre el acceso abierto de la investigación científica, esta obra se pone a disposición del público en su versión electrónica en el repositorio de la uaemex (http:// ri.uaemex.mx) para su uso en línea con fines académicos y no de lucro, por lo que se prohíbe la reproducción parcial o total, directa o indirecta del contenido de esta presentación impresa sin contar previamente con la autorización expresa y por escrito de GEMAporrúa, en términos de lo así previsto por la Ley Federal del Derecho de Autor y, en su caso, por los tratados internacionales aplicables.Bajo la idea de que "merecemos un mundo distinto al que tenemos", este libro ofrece una serie de reflexiones y análisis sobre la paz, algunos conflictos y ciertas formas de violencia desde el "campo" interdisciplinario denominado Estudios para la Paz y el Desarrollo, que se alienta en la Universidad Autónoma del Estado de México, dentro del programa de Maestría del mismo nombre. Quienes escriben en el texto se ubican: o en el ángulo de la investigación para la paz en estricto sentido, o en el ángulo de la investigación para la paz en sentido amplio, que se estimulan y difunden en dicho programa, y que, desde diferentes posturas, alientan escenarios o acciones encaminadas hacia la paz. El libro está dividido en tres secciones, mismas que corresponden a los temas de paz, conflictos y violencia, donde aparecen reflexiones teóricas o empíricas de autores formados o relacionados en el campo

Automatic Hotspot and Sun Glint Detection in UAV Multispectral Images

Last advances in sensors, photogrammetry and computer vision have led to high-automation levels of 3D reconstruction processes for generating dense models and multispectral orthoimages from Unmanned Aerial Vehicle (UAV) images. However, these cartographic products are sometimes blurred and degraded due to sun reflection effects which reduce the image contrast and colour fidelity in photogrammetry and the quality of radiometric values in remote sensing applications. This paper proposes an automatic approach for detecting sun reflections problems (hotspot and sun glint) in multispectral images acquired with an Unmanned Aerial Vehicle (UAV), based on a photogrammetric strategy included in a flight planning and control software developed by the authors. In particular, two main consequences are derived from the approach developed: (i) different areas of the images can be excluded since they contain sun reflection problems; (ii) the cartographic products obtained (e.g., digital terrain model, orthoimages) and the agronomical parameters computed (e.g., normalized vegetation index-NVDI) are improved since radiometric defects in pixels are not considered. Finally, an accuracy assessment was performed in order to analyse the error in the detection process, getting errors around 10 pixels for a ground sample distance (GSD) of 5 cm which is perfectly valid for agricultural applications. This error confirms that the precision in the detection of sun reflections can be guaranteed using this approach and the current low-cost UAV technology

Aspirara un mundo distinto

En cumplimiento a la normatividad sobre el acceso abierto de la investigación científica, esta obra se pone a disposición del público en su versión electrónica en el repositorio de la uaemex (http:// ri.uaemex.mx) para su uso en línea con fines académicos y no de lucro, por lo que se prohíbe la reproducción parcial o total, directa o indirecta del contenido de esta presentación impresa sin contar previamente con la autorización expresa y por escrito de GEMAporrúa, en términos de lo así previsto por la Ley Federal del Derecho de Autor y, en su caso, por los tratados internacionales aplicables.Bajo la idea de que "merecemos un mundo distinto al que tenemos", este libro ofrece una serie de reflexiones y análisis sobre la paz, algunos conflictos y ciertas formas de violencia desde el "campo" interdisciplinario denominado Estudios para la Paz y el Desarrollo, que se alienta en la Universidad Autónoma del Estado de México, dentro del programa de Maestría del mismo nombre. Quienes escriben en el texto se ubican: o en el ángulo de la investigación para la paz en estricto sentido, o en el ángulo de la investigación para la paz en sentido amplio, que se estimulan y difunden en dicho programa, y que, desde diferentes posturas, alientan escenarios o acciones encaminadas hacia la paz. El libro está dividido en tres secciones, mismas que corresponden a los temas de paz, conflictos y violencia, donde aparecen reflexiones teóricas o empíricas de autores formados o relacionados en el campo

XV International Congress of Control Electronics and Telecommunications: "The role of technology in times of pandemic and post-pandemic: innovation and development for strategic social and productive sectors"

La anterior selección, motivados por la aseveración de Manuel Castells -hace casi 20 años ya- que la innovación y la difusión de la tecnología parecía ser la herramienta apropiada para el desarrollo en la era de la información. Este 2020, sin embargo, ante la situación disruptiva que aquejó y aqueja a la sociedad red como una estructura social emergente de la Era de la Información basada en redes de producción, energizadas por el poder y la experiencia; falló y debe reencontrar su rumbo. Es así que los problemas acuciantes, ahora, fueron: la atención sanitaria y la superación de la epidemia de Sars Cov 2; tomó forma la, hasta entonces, visión irrealista de Castells que … no podemos avanzar con nuestros modelos de desarrollo actual, destruyendo nuestro entorno y excluyendo a la mayor parte de la humanidad de los beneficios de la revolución tecnológica más extraordinaria de la historia, sin sufrir una devastadora reacción por parte de la sociedad y la naturaleza. Fue así que el Cuarto Mundo, específicamente, donde la suficiencia de recurso humano, de capital, trabajo, información y mercado -vinculados todos a través de la tecnología- supuso que atendería eficazmente a través de la población que podía por su capacidad hacer uso racional y profesional del conocimiento, las necesidades de la mayoritaria población vulnerable y vulnerada. Por lo anterior, poner en el centro a las personas, en entornos de tarea y trabajo globales hiperconectados combinando espacios físicos, corrientes de información con canales de conexión expeditos, y formando profesionales del conocimiento que asuman y afronten los retos derivados de la transformación digital de empresas, universidades, y organizaciones, pero en condiciones de equidad y sujetos de prosperidad, será el desafío en los escenarios presentes y futuros inmediatos.The previous selection, motivated by the assertion of Manuel Castells -almost 20 years ago- that innovation and diffusion of technology seemed to be the appropriate tool for development in the information age. This 2020, however, in the face of the disruptive situation that afflicted and continues to afflict the network society as an emerging social structure of the Information Age based on production networks, energized by power and experience; He failed and must find his way again. Thus, the pressing problems now were: health care and overcoming the Sars Cov 2 epidemic; Castells' until then unrealistic vision took shape that... we cannot advance with our current development models, destroying our environment and excluding the majority of humanity from the benefits of the most extraordinary technological revolution in history, without suffering a devastating reaction from society and nature. It was thus that the Fourth World, specifically, where the sufficiency of human resources, capital, work, information and market - all linked through technology - meant that it would serve effectively through the population that could, due to its capacity, make rational use. and knowledge professional, the needs of the majority vulnerable and vulnerable population. Therefore, putting people at the center, in hyperconnected global task and work environments, combining physical spaces, information flows with expedited connection channels, and training knowledge professionals who assume and face the challenges derived from the digital transformation of companies, universities, and organizations, but in conditions of equality and subject to prosperity, will be the challenge in the present and immediate future scenarios.Bogot

Outcomes of Patients Presenting with Mild Acute Respiratory Distress Syndrome Insights from the LUNG SAFE Study

BACKGROUND: Patients with initial mild acute respiratory distress syndrome are often underrecognized and mistakenly considered to have low disease severity and favorable outcomes. They represent a relatively poorly characterized population that was only classified as having acute respiratory distress syndrome in the most recent definition. Our primary objective was to describe the natural course and the factors associated with worsening and mortality in this population. METHODS: This study analyzed patients from the international prospective Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) who had initial mild acute respiratory distress syndrome in the first day of inclusion. This study defined three groups based on the evolution of severity in the first week: "worsening" if moderate or severe acute respiratory distress syndrome criteria were met, "persisting" if mild acute respiratory distress syndrome criteria were the most severe category, and "improving" if patients did not fulfill acute respiratory distress syndrome criteria any more from day 2. RESULTS: Among 580 patients with initial mild acute respiratory distress syndrome, 18% (103 of 580) continuously improved, 36% (210 of 580) had persisting mild acute respiratory distress syndrome, and 46% (267 of 580) worsened in the first week after acute respiratory distress syndrome onset. Global in-hospital mortality was 30% (172 of 576; specifically 10% [10 of 101], 30% [63 of 210], and 37% [99 of 265] for patients with improving, persisting, and worsening acute respiratory distress syndrome, respectively), and the median (interquartile range) duration of mechanical ventilation was 7 (4, 14) days (specifically 3 [2, 5], 7 [4, 14], and 11 [6, 18] days for patients with improving, persisting, and worsening acute respiratory distress syndrome, respectively). Admissions for trauma or pneumonia, higher nonpulmonary sequential organ failure assessment score, lower partial pressure of alveolar oxygen/fraction of inspired oxygen, and higher peak inspiratory pressure were independently associated with worsening. CONCLUSIONS: Most patients with initial mild acute respiratory distress syndrome continue to fulfill acute respiratory distress syndrome criteria in the first week, and nearly half worsen in severity. Their mortality is high, particularly in patients with worsening acute respiratory distress syndrome, emphasizing the need for close attention to this patient population.status: publishe

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates