1,354,341 research outputs found
Seismic Investigation for the Characterization of a Gravity Concrete Dam
No full textMonitoring of large-scale infrastructures plays an important role for public safety and prevention. The control of the safety assessment of a dam is largely dependent on knowledge of the mechanical parameters of the actual construction, as well as its geological substratum. The application of geophysical methods can considerably contribute to the examination indicating the less consolidated material and the degradation of mechanical parameters. A seismic tomographic approach has been used in a typical gravity concrete dam without reinforcement to detect mechanical properties of the body of the dam and its geological setting. Three seismic travel time tomographies in the dam body as well as S-wave velocity values obtained by a down hole testify that the dam is composed of high quality concrete. Small variations on the P-wave velocities seem to be the effect of moisture and infiltration. In addition seismic surveys in the surrounding grounds of the dam confirmed the expected properties of the foundation terrain
Development and Use of Assistive Technologies in Spinal Cord Injury: A Narrative Review of Reviews on the Evolution, Opportunities, and Bottlenecks of Their Integration in the Health Domain
No full textAssistive technologies are increasingly taking a leading role in supporting people with spinal cord injury (SCI). This narrative review of reviews intends to contribute by making a map point investigating the integration of ATs in SCI. The methodology of the review was based on: (I) a search of PubMed and Scopus and (II) an eligibility assessment using specific parameters. The outcome highlighted the following: -The evolution of ATs considered in the context of SCI, considering ATs as both products and/or services in standalone and/or networked devices, and as processes of delivery. -Innovative technologies could play an important role in improving the quality of life and in minimizing costs in healthcare. -The international scientific community has identified ATs as one of the six strategic development areas in SCI. The overview also allowed the detection of some problems: (I) The ethical and regulatory aspects have been addressed in a weak way and only in specific and limited cases. (II) There is a lack of studies on the use and applications of ATs in SCI with a focus in multiple domains (e.g., costs, acceptance, dissemination, problems, regulatory aspects, ethical aspects, and other issues important for integration into the health domain). This review highlights the need for further studies and activities focused on integrating consensus in multiple domains, including ethics and regulations, to aid researchers and decision-makers in the field
A series elastic composite actuator for soft arm exosuits
No full textThe paper introduces a novel type of actuator for soft wearable exoskeletons providing assistance to the elbow joint motion. The mechanism consists of two DC motors, a multistable composite transmission which introduces series elastic properties, a high-efficiency non-backdrivable mechanism and a pair of Bowden cables to transmit the motion from the actuator to the joint. A test bench has been designed to experimentally characterize the performance of the proposed device. The control architecture is then introduced and described. The results of preliminary tests are shown and discussed. In conclusion, future developments and a embodiment of the envisioned application are introduced
Seismic tomography tests applied to a gravity dam
No full textThe control of the safety assessment of a dam is largely dependent on knowledge of the mechanical parameters of the actual construction, as well as its geological substratum. The application of geophysical methods can be used in existing dams to evaluate the materials (strength properties) and to verify if they match design expectations, as well as to contribute to the safety control. In particular seismics methods can considerably contribute to the examination indicating the less consolidated material and the degradation of mechanical parameters.
For the characterization of the concrete conservation three seismic tomographies and a vertical seismic profile on the dam body were performed.The vertical seismic profile showed P-wave velocity ranging between 3800 m/s 4750 m/s and S-wave velocity ranging between 1100 m/s and 2520 m/s. Also in this case lower values are present in the upper part of the dam body, as well as show the three seismic tomographies. Even Poisson ratios show typical values of the concrete in good condition, varying between 0.29 and 0.41 (at the upper part of the dam body), which are representative values for concrete
Organic waste materials for Bioengineering works
No full textBioengineering uses plant and biodegradable materials of natural origin, stones, steel, additives and synthetic products in various combinations and as support for the growth of plants. The lack of available resources and progressive increasing of desertification in Sicily, led to the search for alternative materials. Objective of the work is testing organic waste materials for the realization of bioengineering works in the several areas of application: terrestrial, fluvial and coastline. To this aim, is proposed the use of innovative techniques that involve the construction of low-cost brushwood, environmentally friendly materials made: the pruning of vines and the oceanic Posidonia oceanica beached (banquette). The use of these two organic materials, which are a special solid waste, widely present in Sicily, is part of an efficient use of resources while respecting the environment. Assembled by hand or mechanically in the form of fascine or biocarpet, the residues of the vine pruning will constitute the modular element to achieve anti-erosion linear works while the residues of Posidonia oceanica (previously leached), constitute the growing media which, along sowing or planting of native species, make it "alive" the artefact
A Non-Iterative Approach to Direct Data-Driven Control Design of MIMO LTI Systems
No full textThis paper proposes a non-iterative direct data-driven technique that deals with linear time-invariant (LTI) controller design by directly identifying the controller from input-output data without using plant identification. We define the feasible controller parameter set and formulate the problem of designing a controller to match the behaviour of a given reference model as an equivalent set-membership errors-in-variables problem. Then we design the controller parameters by applying recent results in set-membership errors-in-variables identification. Finally, we analyse the effectiveness of the presented technique through simulation examples and experimental results
Unconventional Arrays for 3D Electrical Resistivity and Induced Polarization Tomography to Detect Leachate Concentration in a Waste Landfill
No full textIn recent times, 3D electrical resistivity and induced polarization tomographies are being used more frequently. However, it is often not possible to have regular grids of electrodes due to irregular topography, difficulty accessing urbanized or industrialized places, and other environmental and health problems. In these cases, the use of unconventional arrays is necessary, arranging the electrodes around the inaccessible area according to one or more open or closed polygonal traces. In this work, three different perimeter arrangements of electrodes are considered, and, for each, three different electrode array configurations are tested by calculating their apparent resistivity and solving the inverse problem on a three-dimensional model with resistive and conductive blocks. The comparison of the results showed that the dataset that produces the most realistic inverse model consists of electrodes arranged in concentric squares and the use of the Full Range Gradient (FRG) Array. This combination was evaluated in the field on a waste landfill, in which electrical resistivity and induced polarization tomographies were carried out, exploiting the access paths to the various sectors of the landfill to arrange the electrodes on approximately concentric polygons. The 3D models of electrical resistivity and induced polarization allowed the detection of zones of high concentration of leachate, defining their extension, and monitoring the functioning of the waterproofing membrane at the bottom of the landfill. The results proved that when it is not possible to arrange a regular grid of electrodes, the use of perimeter disposals of electrode joined to the FRG array provide a sufficiently homogeneous resolution below the area to be investigated
Ethics and Automated Systems in the Health Domain: Design and Submission of a Survey on Rehabilitation and Assistance Robotics to Collect Insiders’ Opinions and Perception
No full textBackground: The problem of the relationship between ethics and robotics is very broad, has important implications, and has two large areas of impact: the first is conduct in research, development, and use in general. The second is the implication of the programming of machine ethics. Purpose: Develop and administer a survey of professionals in the health domain collection of their positions on ethics in rehabilitation and assistance robotics. Methods: An electronic survey was designed using Microsoft Forms and submitted to 155 professionals in the health domain (age between 23 and 64 years; 78 males, mean age 43.7, minimum age 24, maximum age 64; 77 females, mean age 44.3, minimum age 23, maximum age 64) using social media. Results and discussion: The outcome returned: (a) the position on ethics training during university studies and in the world of work, (b) the organizational aspects hindered by ethics and those to be perfected in relation to ethics, (c) issues of ethical concern, (d) structured feedback on the usefulness of the methodology along with considerations of open text. Conclusions: An electronic survey methodology has allowed the structured collection of information on positions towards ethics in this sector. Encouraging feedback from the participants suggests the continuation of the study is beneficial. A continuation is expected, expanding the audience of professionals involved and perfecting the survey with the support of scientific companies
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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