Lying-People Pressure-Map Datasets: A Systematic Review

Bedded or lying-people pressure-map datasets can be used to identify patients’ in-bed postures and can be very useful in numerous healthcare applications. However, the construction of these datasets is not always easy, and many researchers often resort to existing datasets to carry out their experiments and validate their solutions. This systematic review aimed to identify and characterise pressure-map datasets on lying-people- or bedded-people positions. We used a systematic approach to select nine studies that were thoroughly reviewed and summarised them considering methods of data collection, fields considered in the datasets, and results or their uses after collection. As a result of the review, six research questions were answered that allowed a characterisation of existing datasets regarding of the types of data included, number and types of poses considered, participant characteristics and size of the dataset, and information on how the datasets were built. This study might represent an important basis for academics and researchers to understand the information collected in each pressure-map dataset, the possible uses of such datasets, or methods to build new datasets.info:eu-repo/semantics/publishedVersio

First results from the LUCID-Timepix spacecraft payload onboard the TechDemoSat-1 satellite in Low Earth Orbit

The Langton Ultimate Cosmic ray Intensity Detector (LUCID) is a payload onboard the satellite TechDemoSat-1, used to study the radiation environment in Low Earth Orbit ($\sim$635km). LUCID operated from 2014 to 2017, collecting over 2.1 million frames of radiation data from its five Timepix detectors on board. LUCID is one of the first uses of the Timepix detector technology in open space, with the data providing useful insight into the performance of this technology in new environments. It provides high-sensitivity imaging measurements of the mixed radiation field, with a wide dynamic range in terms of spectral response, particle type and direction. The data has been analysed using computing resources provided by GridPP, with a new machine learning algorithm that uses the Tensorflow framework. This algorithm provides a new approach to processing Medipix data, using a training set of human labelled tracks, providing greater particle classification accuracy than other algorithms. For managing the LUCID data, we have developed an online platform called Timepix Analysis Platform at School (TAPAS). This provides a swift and simple way for users to analyse data that they collect using Timepix detectors from both LUCID and other experiments. We also present some possible future uses of the LUCID data and Medipix detectors in space.Comment: Accepted for publication in Advances in Space Researc

Parâmetros relevantes para caracterização de rios montanhosos : revisão

Mountain rivers are situated in a large portion of the terrestrial surface, especially in headwaters regions, and have been used for various purposes such as recreation, sporting activities, water resources and hydroelectric power generation. However, hydrogeomorphic characteristics of mountain rivers are not fully understood. In this context, the present paper aimed to identify relevant parameters for characterizing rivers in these environments based on bibliographical review. It was identified which parameters have been used and how they have been used to characterize mountain rivers in distinct classifications. The most cited parameters were channel gradient, relation between river width and depth, entrenchment ratio, discharge, sediment transport and grain-size distribution. Also, the current situation related to researches in fluvial geomorphology in mountain rivers in Brazil was evaluated, and the strong need of field survey as basis for the best understanding of mountain fluvial dynamics and characterization was verified.Rios montanhosos estão presentes em uma grande porção dos territórios do planeta, especialmente nas regiões de cabeceiras, e vêm sendo utilizados para diversos fins, tais como recreação e atividades desportivas, mananciais de água e geração de energia hidrelétrica. Entretanto, suas características hidrogeomorfológicas ainda não são plenamente conhecidas. Neste contexto, o presente trabalho abordou os parâmetros relevantes necessários para caracterização de rios nestes ambientes a partir de revisão bibliográfica, em que se buscou avaliar o modo como os rios estavam sendo caracterizados e quais parâmetros hidrogeomorfológicos estavam sendo analisados em diferentes classificações. Os parâmetros mais comumente utilizados na caracterização de rios montanhosos são a declividade do canal, a relação entre largura e profundidade do rio, o grau de entrincheiramento do canal, a vazão, a carga de sedimentos e a granulometria dos sedimentos. Ainda, avaliou-se o cenário brasileiro no que tange a pesquisa em hidrogeomorfologia fluvial em rios montanhosos, constatando-se a necessidade de realizar mais atividades em campo para melhor entendimento da dinâmica fluvial montanhosa e caracterização fluvial

Parâmetros relevantes para caracterização de rios montanhosos : revisão

Mountain rivers are situated in a large portion of the terrestrial surface, especially in headwaters regions, and have been used for various purposes such as recreation, sporting activities, water resources and hydroelectric power generation. However, hydrogeomorphic characteristics of mountain rivers are not fully understood. In this context, the present paper aimed to identify relevant parameters for characterizing rivers in these environments based on bibliographical review. It was identified which parameters have been used and how they have been used to characterize mountain rivers in distinct classifications. The most cited parameters were channel gradient, relation between river width and depth, entrenchment ratio, discharge, sediment transport and grain-size distribution. Also, the current situation related to researches in fluvial geomorphology in mountain rivers in Brazil was evaluated, and the strong need of field survey as basis for the best understanding of mountain fluvial dynamics and characterization was verified.Rios montanhosos estão presentes em uma grande porção dos territórios do planeta, especialmente nas regiões de cabeceiras, e vêm sendo utilizados para diversos fins, tais como recreação e atividades desportivas, mananciais de água e geração de energia hidrelétrica. Entretanto, suas características hidrogeomorfológicas ainda não são plenamente conhecidas. Neste contexto, o presente trabalho abordou os parâmetros relevantes necessários para caracterização de rios nestes ambientes a partir de revisão bibliográfica, em que se buscou avaliar o modo como os rios estavam sendo caracterizados e quais parâmetros hidrogeomorfológicos estavam sendo analisados em diferentes classificações. Os parâmetros mais comumente utilizados na caracterização de rios montanhosos são a declividade do canal, a relação entre largura e profundidade do rio, o grau de entrincheiramento do canal, a vazão, a carga de sedimentos e a granulometria dos sedimentos. Ainda, avaliou-se o cenário brasileiro no que tange a pesquisa em hidrogeomorfologia fluvial em rios montanhosos, constatando-se a necessidade de realizar mais atividades em campo para melhor entendimento da dinâmica fluvial montanhosa e caracterização fluvial

INVESTIGATION ON THE CUTTING PARTICLES TRANSPORT IN HORIZONTAL WELL DRILLING

Arguably the most important prerequisite function to permit further progress in well drilling operations up to reach production is a complete removal of drilled cuttings from the well bore. This target becomes more challenging in highly-deviated to horizontal wells, where the cuttings particles have more tendency to accumulate in the lower side of the well bore and form a bed of standstill cuttings. In this study, a mathematical model based on the mechanistic theory and the three-layer approach was developed to simulate the cutting particles transport in annular flow during the horizontal drilling process. Two mathematical models were developed to investigate the cuttings transportation performance in horizontal wells. Due to high non- linearity, both were solved numerically after conversion to computer algorithms using MATLAB. The master model examined the performance of irregular shaped cuttings transported in concentric annulus by non-Newtonian fluids. The model predicted the velocities of the layers, the layer’s concentration, the dispersive shear stress, and the pressure drop. The transport performance was adequately simulated under various operational and design conditions, namely the effect of the cuttings size, cuttings shape, annular size, rate of penetration and the mud rheology in term of fluid viscosity. The second model represented a modified model which used to test the sensitivity of the frictional forces calculations, where empirical correlations were employed to replace Szilas formula to calculate the layers and wall friction stresses. The cuttings size, mud viscosity and annular size demonstrated significant effect on transport process. While the operational rate of penetration performed the lowest effect between the entire parameters of the cuttings transport. The results compared favorably with those obtained by previous investigators. Accordingly, the simulations demonstrated that the basic model could be used to analyze the cuttings transport. Thereby, it could potentially be used as design and/or analysis tools for the follow-up of transport processes in horizontal wells

Description of the Baseline Surface Radiation Network (BSRN) station at the Izaña Observatory (2009–2017): measurements and quality control/assurance procedures [Discussion]

The Baseline Surface Radiation Network (BSRN) was implemented by the World Climate Research Programme (WRCP) starting observations with 9 stations in 1992, under the auspices of the World Meteorological Organization (WMO). Currently, 59 BSRN stations submit their data to the WRCP. One of these stations is the Izaña station (Station: IZA, #61) that enrolled in this network in 2009. This is a high-mountain station located in Tenerife (Canary Islands, Spain; at 28.3°N, 16.5°W, 2373ma.s.l.) and is a representative site of the subtropical North Atlantic free troposphere. It contributes with basic-BSRN radiation measurements, such as, global shortwave radiation (SWD), direct radiation (DIR), diffuse radiation (DIF) and longwave downward radiation (LWD) and extended-BSRN measurements, including ultraviolet ranges (UV-A and UV-B), shortwave upward radiation (SWU) and longwave upward radiation (LWU) and other ancillary measurements, such as vertical profiles of temperature, humidity and wind obtained from radiosonde (WMO, station #60018) and total column ozone from Brewer spectrophotometer. The IZA measurements present high quality standards since more than 98% of the data are within the limits recommended by the BSRN. There is an excellent agreement in the comparison between SWD, DIR and DIF (instantaneous and daily) measurements with simulations obtained with the LibRadtran radiative transfer model. The root mean square error (RMSE) for SWD is 2.28% for instantaneous values and 1.58% for daily values, while the RMSE for DIR is 2.00% for instantaneous values and 2.07% for daily values. IZA is a unique station that provides very accurate solar radiation data in very contrasting scenarios: most of the time under pristine sky conditions, and periodically under the effects of the Saharan Air Layer characterized by a high content of mineral dust. A detailed description of the BSRN program at IZA, including quality control and quality assurance activities, is given in this work.The IZA BSRN program has benefited from results obtained within POLARMOON project funded by the Ministerio de Economía y Competividad from Spain, CTM2015-66742-R

Use of a-shapes for the measurement of 3D bubbles in fluidized beds from two-fluid model simulations

A geometrical technique based on shape construction was employed to reconstruct the simulated domain of 3D bubbles in a gas-solid fluidized bed, from two-fluid model (TFM) simulations. The Delaunay triangulation of the cloud of points that represent volume fraction iso-surfaces in transient TFM simulations was filtered by means of the so-called a-shapes, allowing a topologically accurate description of 3D bubbles within a fluidized bed. Consequently, individual 3D bubble properties such as size and velocity were measured. Simulated bubble characteristics were further compared to those measured on pseudo-2D bed facilities by image techniques in order to illustrate the effect of the bed geometry on the bubbling behavior under mimicked operational conditions

Investigating the potential of using hydrocyclone-fine screen hybrid systems to improve the performance of classification circuits

Classification is an integral part of comminution operations that controls the performance of the circuit. Hydrocyclones are normally used to perform the classification function. They offer numerous advantages that include, the ability to handle high throughputs, low floor space occupation and relatively low capital and running costs. Despite these advantages, hydrocyclones are inherently inefficient classifiers as they are predominantly dependent on hydrodynamics to effect separation. This effect is more prominent in operations handling complex ores such as a dual-density ore, where the heavy fine particles are misplaced to the underflow and the lighter middling particles report to the overflow. Several attempts have been made to improve the separation efficiency of cyclones either by modification of the cyclone or use of multi-stage cycloning. Most of the results obtained from experimental and simulation studies have shown considerable improvements. Even though some have not yet found wide application in the minerals industry due to practical limitations related to control and unstable operations. More recently, fine screening has gained recognition in the classification role. This development has allowed the use of fine screens in closed-circuit grinding operations resulting in significant metallurgical and economic benefits. Screens provide a sharper cut at the desired size and reduce the fraction of fines bypassing classification compared to hydrocyclones but have capacity limitations at smaller apertures. In an effort to mitigate the classification challenges of both the hydrocyclone and fine screen, this study investigated the potential of combining the high throughput performance of the hydrocyclone operation and the high precision classification characteristics of fine screening to result in a hybrid classification circuit Plant scale tests were conducted using five different classification circuit configurations at an operational Base Metal Concentrator treating a polymetallic ore. The classification circuit configurations considered included (i) a two-stage hydrocyclone with primary underflow reclassification (ii) an inclined hydrocyclone, (iii) a fine screen and (iv) selected permutations of hybrid circuit designs that included a hydrocyclone-fine screen (2 stage) and two hydrocyclones-fine screen (3 stage) variants of the hybridised configurations. The efficiency curves and their respective key performance indicators were used to assess the performance of the circuit configurations tested. The results showed that classification circuits that included fine screens exhibited higher sharpness of separation compared to circuit configurations comprised of hydrocyclones. The fine screen configuration showed the sharpest separation while the hydrocyclone-fine screen hybrid configurations gave relatively higher separation efficiencies than the configurations with hydrocyclones only. The overall sharpness of separation values obtained for the two stage and three-stage hybrid circuits were 3.0 and 2.4, respectively. The two-stage hydrocyclone and inclined hydrocyclone circuits had sharpness of separation values of 1.7 and 0.5, respectively. The inclined hydrocyclone circuit configuration performed the poorest. Furthermore, the two-stage hybrid circuit showed a higher degree of separation compared to the three-stage hybrid configuration. However, it was observed that a finer corrected cut size was realised for the three-stage hybrid circuit design. The fishhook effect was seen at particle sizes less than 38μm for the configurations incorporating a fine screen and an inclined hydrocyclone. Notably, the effect appeared to be more pronounced in configurations involving a fine screen stage. The results have shown that application of hybrid classification configurations can improve the performance of classification circuits. In addition, reclassification of hydrocyclone underflow on fine screens will results in a sharper classification while reclassifying the overflow stream on fine screens will provide a clean circuit final product. An evaluation of the capital and operating costs associated with fine screens should be done to determine the economic feasibility of incorporating the units in conventional milling circuits

Description of the Baseline Surface Radiation Network (BSRN) station at the Izaña Observatory (2009–2017): measurements and quality control/assurance procedures

The Baseline Surface Radiation Network (BSRN) was implemented by the World Climate Research Programme (WCRP) starting observations with nine stations in 1992, under the auspices of the World Meteorological Organization (WMO). Currently, 59 BSRN stations submit their data to the WCRP. One of these stations is the Izaña station (station IZA, no. 61) that enrolled in this network in 2009. This is a high-mountain station located in Tenerife (Canary Islands, Spain, at 28.3∘ N, 16.5∘ W; 2373 m a.s.l.) and is a representative site of the subtropical North Atlantic free troposphere. It contributes with basic-BSRN radiation measurements, such as global shortwave radiation (SWD), direct radiation (DIR), diffuse radiation (DIF) and longwave downward radiation (LWD), and extended-BSRN measurements, including ultraviolet ranges (UV-A and UV-B), shortwave upward radiation (SWU) and longwave upward radiation (LWU), and other ancillary measurements, such as vertical profiles of temperature, humidity and wind obtained from radiosonde profiles (WMO station no. 60018) and total column ozone from the Brewer spectrophotometer. The IZA measurements present high-quality standards since more than 98 % of the data are within the limits recommended by the BSRN. There is an excellent agreement in the comparison between SWD, DIR and DIF (instantaneous and daily) measurements with simulations obtained with the LibRadtran radiative transfer model. The root mean square error (RMSE) for SWD is 2.28 % for instantaneous values and 1.58 % for daily values, while the RMSE for DIR is 2.00 % for instantaneous values and 2.07 % for daily values. IZA is a unique station that provides very accurate solar radiation data in very contrasting scenarios: most of the time under pristine sky conditions and periodically under the effects of the Saharan air layer characterized by a high content of mineral dust. A detailed description of the BSRN program at IZA, including quality control and quality assurance activities, is given in this work.The IZA BSRN program has benefited from results obtained within POLARMOON project funded by the Ministerio de Economía y Competividad from Spain, CTM2015-66742-R

Experimental Analysis of Gas–Liquid–Solid Three-Phase Flows in Horizontal Pipelines

The dynamics of three-phase flows involves phenomena of high complexity whose characterization is of great interest for different sectors of the worldwide industry. In order to move forward in the fundamental knowledge of the behavior of three-phase flows, new experimental data has been obtained in a facility specially designed for flow visualization and for measuring key parameters. These are (1) the flow regime, (2) the superficial velocities or rates of the individual phases; and (3) the frictional pressure loss. Flow visualization and pressure measurements are performed for two and three-phase flows in horizontal 30 mm inner diameter and 4.5 m long transparent acrylic pipes. A total of 134 flow conditions are analyzed and presented, including plug and slug flows in air–water two-phase flows and air–water-polypropylene (pellets) three-phase flows. For two-phase flows the transition from plug to slug flow agrees with the flow regime maps available in the literature. However, for three phase flows, a progressive displacement towards higher gas superficial velocities is found as the solid concentration is increased. The performance of a modified Lockhart–Martinelli correlation is tested for predicting frictional pressure gradient of three-phase flows with solid particles less dense than the liquid