51 research outputs found
Simplified Vehicle-Bridge Interaction for Medium to Long-span Bridges Subject to Random Traffic Load
This study introduces a simplified model for bridge-vehicle interaction for
medium- to long-span bridges subject to random traffic loads. Previous studies
have focused on calculating the exact response of the vehicle or the bridge
based on an interaction force derived from the compatibility between two
systems. This process requires multiple iterations per time step per vehicle
until the compatibility is reached. When a network of vehicles is considered,
the compatibility equation turns to a system of coupled equations which
dramatically increases the complexity of the convergence process. In this
study, we simplify the problem into two sub-problems that are decoupled: (a) a
bridge subject to random Gaussian excitation, and (b) individual sensing agents
that are subject to a linear superposition of the bridge response and the road
profile roughness. The study provides sufficient evidence to confirm the
simulation approach is valid with a minimal error when the bridge span is
medium to long, and the spatio-temporal load pattern can be modeled as random
Gaussian. Quantitatively, the proposed approach is over 1,000 times more
computationally efficient when compared to the conventional approach for a 500
m long bridge, with response prediction errors below .Comment: submitted to the Journal of Civil Structural Health Monitorin
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Indirect structural health monitoring (iSHM) of transport infrastructure in the digital age
Workshop reportCopyright © Joint Research Centre (European Commission). The existing European motorway infrastructure network is prone to ageing and subject to natural events (e.g. climate change) and hazards (e.g. earthquakes), necessitating immediate actions for its maintenance and
safety. Within this context, the structural health monitoring (SHM) framework allows a quantitative assessment of the structural integrity, serviceability and performance, facilitating better-informed decisions for the management of the existing infrastructure. The European Commission Joint Research Centre (JRC) established the exploratory research project MITICA (Monitoring Transport Infrastructures with Connected and Automated vehicles) to investigate the opportunity to use novel methods for infrastructure motoring, aiming at the efficient
maintenance of the European aging road infrastructure. This report summarizes the discussion and the outcomes of a workshop held at the JRC in Ispra (Italy) on June 6-7 2022, as part of the MITICA project.
Considering the EU priority “A Europe fit for the digital age”, the workshop was dedicated to SHM and its application to civil infrastructure, focusing on innovative indirect structural health monitoring (iSHM) approaches that rely on the vehicle-bridge interaction and the deployment of sensor-equipped vehicles for the monitoring of the existing bridge infrastructure. The report aims to become a reference document in the area of iSHM using passing vehicles, for both scholars and policy makers
From Personalized Medicine to Population Health: A Survey of mHealth Sensing Techniques
Mobile Sensing Apps have been widely used as a practical approach to collect
behavioral and health-related information from individuals and provide timely
intervention to promote health and well-beings, such as mental health and
chronic cares. As the objectives of mobile sensing could be either \emph{(a)
personalized medicine for individuals} or \emph{(b) public health for
populations}, in this work we review the design of these mobile sensing apps,
and propose to categorize the design of these apps/systems in two paradigms --
\emph{(i) Personal Sensing} and \emph{(ii) Crowd Sensing} paradigms. While both
sensing paradigms might incorporate with common ubiquitous sensing
technologies, such as wearable sensors, mobility monitoring, mobile data
offloading, and/or cloud-based data analytics to collect and process sensing
data from individuals, we present a novel taxonomy system with two major
components that can specify and classify apps/systems from aspects of the
life-cycle of mHealth Sensing: \emph{(1) Sensing Task Creation \&
Participation}, \emph{(2) Health Surveillance \& Data Collection}, and
\emph{(3) Data Analysis \& Knowledge Discovery}. With respect to different
goals of the two paradigms, this work systematically reviews this field, and
summarizes the design of typical apps/systems in the view of the configurations
and interactions between these two components. In addition to summarization,
the proposed taxonomy system also helps figure out the potential directions of
mobile sensing for health from both personalized medicines and population
health perspectives.Comment: Submitted to a journal for revie
A Survey on Mobile Crowdsensing Systems: Challenges, Solutions, and Opportunities
Mobile crowdsensing (MCS) has gained significant attention in recent years and has become an appealing paradigm for urban sensing. For data collection, MCS systems rely on contribution from mobile devices of a large number of participants or a crowd. Smartphones, tablets, and wearable devices are deployed widely and already equipped with a rich set of sensors, making them an excellent source of information. Mobility and intelligence of humans guarantee higher coverage and better context awareness if compared to traditional sensor networks. At the same time, individuals may be reluctant to share data for privacy concerns. For this reason, MCS frameworks are specifically designed to include incentive mechanisms and address privacy concerns.
Despite the growing interest in the research community, MCS solutions need a deeper investigation and categorization on many aspects that span from sensing and communication to system management and data storage. In this paper, we take the research on MCS a step further by presenting a survey on existing works in the domain and propose a detailed taxonomy to shed light on the current landscape and classify applications, methodologies, and architectures. Our objective is not only to analyze and consolidate past research but also to outline potential future research directions and synergies with other research areas
Vibration Analysis for Engine fault Detection
In the Vibration analysis for engine fault detection, we use different visualization graph. Today‘s world growing fast and machinery part getting complex so it’s difficult to find out fault in the machine so here means in this paper we explain how we find out the fault of the machine with help of visualization it’s easy to find out a fault here we use angular.js, D3.js for visualization and use MQTT protocol for publishing and subscribe sensor data. In the automobile industries machines are the main part of how we find out fault yes we find out fault with help of sensors using sensors here we analyze the machine
Ambient vibrations of age-old masonry towers: results of long-term dynamic monitoring in the historic centre of Lucca
The paper presents the results of an ambient vibration monitoring campaign
conducted on so-called Clock Tower (Torre delle Ore), one the best known and
most visited monuments in the historic centre of Lucca. The vibrations of the
tower were continuously monitored from November 2017 to March 2018 using
high-sensitivity instrumentation. In particular, four seismic stations provided
by the Istituto Nazionale di Geofisica e Vulcanologia and two three-axial
accelerometers developed by AGI S.r.l., spin-off of the Istituto Nazionale di
Astrofisica, were installed on the tower. The measured vibration level was
generally very low, since the structure lies in the middle of a limited traffic
area. Nevertheless, the availability of two different types of highly sensitive
and accurate instruments allowed the authors to follow the dynamic behaviour of
the tower during the entire monitoring period and has moreover provided
cross-validation of the results
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