202 research outputs found

    Sensitivity Analysis and Calibration of a Rainfall-runoff Model with the Combined Use of EPA-SWMM and Genetic Algorithm

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    An integrated Visual Basic Application interface is described that allows for sensitivity analysis, calibration and routing of hydraulichydrological models. The routine consists in the combination of three freeware tools performing hydrological modelling, hydraulic modelling and calibration. With such an approach, calibration is made possible even if information about sewers geometrical features is incomplete. Model parameters involve storage coefficient, time of concentration, runoff coefficient, initial abstraction and Manning coefficient; literature formulas are considered and manipulated to obtain novel expressions and variation ranges. A sensitivity analysis with a local method is performed to obtain information about collinearity among parameters and a ranking of influence. The least important parameters are given a fixed value, and for the remaining ones calibration is performed by means of a genetic algorithm implemented in GANetXL. Single-event calibration is performed with a selection of six rainfall events, which are chosen so to avoid non-uniform rainfall distribution; results are then successfully validated with a sequence of four events

    Digital Twin for Amyotrophic Lateral Sclerosis: a system for patient engagement

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    This chapter focuses on the context in which patients such as those with Amyotrophic Lateral Sclerosis (ALS) are placed and what possibilities information and communication technologies (ICTs) offer to keep them in touch with the world to reach Society 5.0. In particular, the authors intend to show how the healthcare sector can use digital twin (DT) through elements of augmented virtuality (AR) and building information modelling (BIM) to create interactive interfaces that can solve, in part, problems involving frail patients but at the same time allowing their monitoring. Interconnection is possible through a gamification approach. In addition, a solution that considers the user (patient) involvement and that aims at its increase through interaction with alternative places to their home so as to stimulate them to keep an active mind and the degree of fun in a limiting condition is proposed

    Hydraulic Design of a USBR Type II Stilling Basin

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    The present paper deals with a United States Bureau of Reclamation (USBR) Type II stilling basin, which is characterized by blocks at the end of the chute and a dentated sill at the end of the basin. For this basin, USBR only gives overall design criteria concerning basin length and block dimensions on the basis of the assumption that the hydraulic jump remains confined within the sill. No considerations are provided concerning possible different jump types, pressure regimes, and forces acting on the sill. To comply with such a lack, an experimental campaign was undertaken that focuses on the differences among hydraulic jump types that can occur in a USBR Type II stilling basin. Jump types can range between submerged and spray jump types; accordingly, dimensionless relations are provided to predict jump type and position for assigned boundary conditions, with particular concern about the submerged/nonsubmerged distinction. Considerations about the drag force and drag coefficients are provided, along with estimates of pressure extreme fluctuations. Finally, an evaluation of the dissipation efficiency is presented for both submerged and nonsubmerged jumps, enabling comparisons among different jump types and with classical hydraulic jump. - See more at: http://ascelibrary.org/doi/abs/10.1061/(ASCE)IR.1943-4774.0001150#sthash.ajmk3TuB.dpu

    Combining Locations from Working Memory and Long-Term Memory into a Common Spatial Image

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    This research uses a novel integration paradigm to investigate whether target locations read in from long-term memory (LTM) differ from perceptually encoded inputs in spatial working-memory (SWM) with respect to systematic spatial error and/or noise, and whether SWM can simultaneously encompass both of these sources. Our results provide evidence for a composite representation of space in SWM derived from both perception and LTM, albeit with a loss in spatial precision of locations retrieved from LTM. More generally, the data support the concept of a spatial image in working memory and extend its potential sources to representations retrieved from LTM

    Spatial working memory for locations specified by vision and audition: Testing the amodality hypothesis

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    Spatial working memory can maintain representations from vision, hearing, and touch, representations referred to here as spatial images. The present experiment addressed whether spatial images from vision and hearing that are simultaneously present within working memory retain modality-specific tags or are amodal. Observers were presented with short sequences of targets varying in angular direction, with the targets in a given sequence being all auditory, all visual, or a sequential mixture of the two. On two thirds of the trials, one of the locations was repeated, and observers had to respond as quickly as possible when detecting this repetition. Ancillary detection and localization tasks confirmed that the visual and auditory targets were perceptually comparable. Response latencies in the working memory task showed small but reliable costs in performance on trials involving a sequential mixture of auditory and visual targets, as compared with trials of pure vision or pure audition. These deficits were statistically reliable only for trials on which the modalities of the matching location switched from the penultimate to the final target in the sequence, indicating a switching cost. The switching cost for the pair in immediate succession means that the spatial images representing the target locations retain features of the visual or auditory representations from which they were derived. However, there was no reliable evidence of a performance cost for mixed modalities in the matching pair when the second of the two did not immediately follow the first, suggesting that more enduring spatial images in working memory may be amodal

    Perception of 3-D Location Based on Vision, Touch, and Extended Touch

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    Perception of the near environment gives rise to spatial images in working memory that continue to represent the spatial layout even after cessation of sensory input. As the observer moves, these spatial images are continuously updated. This research is concerned with (1) whether spatial images of targets are formed when they are sensed using extended touch (i.e., using a probe to extend the reach of the arm) and (2) the accuracy with which such targets are perceived. In Experiment 1, participants perceived the 3-D locations of individual targets from a fixed origin and were then tested with an updating task involving blindfolded walking followed by placement of the hand at the remembered target location. Twenty-four target locations, representing all combinations of two distances, two heights, and six azimuths, were perceived by vision or by blindfolded exploration with the bare hand, a 1-m probe, or a 2-m probe. Systematic errors in azimuth were observed for all targets, reflecting errors in representing the target locations and updating. Overall, updating after visual perception was best, but the quantitative differences between conditions were small. Experiment 2 demonstrated that auditory information signifying contact with the target was not a factor. Overall, the results indicate that 3-D spatial images can be formed of targets sensed by extended touch and that perception by extended touch, even out to 1.75 m, is surprisingly accurate

    Touch-Screen Technology for the Dynamic Display of 2D Spatial Information Without Vision: Promise and Progress

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    Many developers wish to capitalize on touch-screen technology for developing aids for the blind, particularly by incorporating vibrotactile stimulation to convey patterns on their surfaces, which otherwise are featureless. Our belief is that they will need to take into account basic research on haptic perception in designing these graphics interfaces. We point out constraints and limitations in haptic processing that affect the use of these devices. We also suggest ways to use sound to augment basic information from touch, and we include evaluation data from users of a touch-screen device with vibrotactile and auditory feedback that we have been developing, called a vibro-audio interface

    Experimental results on the physical model of an USBR type II stilling basin

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    The present paper describes the experimental campaign carried on the physical model of the spillway of Lower Diamphwe Dam (Malawi), which is provided with a USBR type II stilling basin. Stilling basins are used in order to reduce the excessive kinetic energy of flowing water downstream of spillways. Specifically, a USBR type II basin is provided with blocks at the end of the chute and with a confining dentated sill; these appurtenances allow to dissipate excess energy with high efficiency. The study focuses on the hydraulic behavior of the stilling basin; tests were carried on for different values of incoming discharge and downstream water depth. Results show the dissipation efficiency of the stilling basin in terms of pressure fluctuation and the variability of the jump type with the hydraulic characteristics of the incoming and the downstream flow depths

    Comparing Different Modelling Strategies for the Estimation of Climate Change Effects on Urban Pluvial Flooding

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    In this paper, two different strategies are presented that allow for the assessment of the effects of climate change on urban pluvial flooding, in order to understand potentialities and limitations, advantages and drawbacks. The two strategies are hereby defined as “top-down” and “bottom-up”, according to the relative position of climate change modelling with respect to flood modelling (upstream for top-down, downstream for bottom-up). To provide a practical example, the two strategies are applied to a case study located in Naples, Italy. However, they can be successfully extended for the assessment of any potential impact of climate change in any location
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