1,721,080 research outputs found
Designing low-cost modified cladding sensors: A structured approach
No full textIn this paper, a novel solution for signal conditioning, fiber illumination, and measurement is proposed for an optical fiber sensor based on a modified cladding sensing element. The presented technique has properties of compactness and low cost, due to the use of very common optoelectronic components, and flexibility, since it could be employed for different kinds of optical fiber sensors. In particular, a prototype has been realized and characterized for the measurement of liquid temperature
IEEE 1451: Communication among smart sensors using MQTT protocol
No full textSmart sensors, transducers, and sensor networks are undergoing, in recent years, a profound transformation thanks to the spread of new communication protocols based on the Producer-Consumer paradigm rather than on the Request-Response paradigm of Server-Client architectures. In this context, the substandard IEEE 1451.1.6 has been introduced in the IEEE 1451 standard, which aims to standardize the Producer-Consumer based communication protocols, particularly MQTT. The role of this standard is fundamental for the realization of sensor networks with nodes produced by different manufacturers and integrated in a fully automatic way according to the paradigm 'Plug and Play'. This work aims to verify the progress of this sub-standard by testing its reliability with the development and testing of a prototype wireless sensor network based on MQTT with low-cost hardware. The prototype will consist of a Network Capable Application Processor (NCAP) node and a Transducer Interface Module (TIM) node, while the role of MQTT Broker and Wi-Fi Access Point for the physical layer of the Wireless Sensor Network will be covered by the NCAP itself
Distance Measurement Characterization for Ultra Wide Band Indoor Localization Systems
No full textLocalization system are widespread both outdoor and indoor and their objectives are various and of obvious importance: navigation, object and person localization and more. Indoor environments are particularly complex for position detection and localization; among several systems and the technologies used, the most commonly used is the Ultra Wide Band for its performance in terms of range and resolution. Any localization method strongly depends on a distance measurement and on its accuracy. In this paper after a short introduction on the state of art of indoor localization and on Ultra Wide Band technology, localization estimation technique is detailed in order to support the following sensor measurement characterization. The paper also report several measurements made on an indoor localization system based on UWB technology and extracts a noise model for the distance measurement. An exponential model for noise is extracted from measurements
Smart Sensor Efficient Signal Processing for Earthquake Early Detection
No full textThis paper presents a new method for earthquake early warning alert that uses a smart sampling technique that expose the signal information in a way that it is simpler to infer knowledge. The objective is to estimate, from the first few seconds of the P wave, if the incoming earthquake is destructive or not. The proposed method is described and compared to conventional approaches. Performance results for real seismic data are shown highlighting the results for earthquakes of different magnitudes. Preliminary results are excellent for inferring damage based on the approach of a single seismic station
Le clausole sociali di riassunzione nella successione di appalti quale strumento di governance per un mercato concorrenziale e socialmente responsabile
No full textLa governance bancaria come risk governance: evoluzione della regolamentazione internazionale e trasposizione nell'ordinamento italiano
No full textIl lavoro affronta il tema della corporate governance delle banche dando conto del dibattito sollevato dalla crisi finanziaria del 2007-2008 e della conseguente evoluzione della disciplina verificatasi a livello internazionale e, correlativamente, sul piano delle fonti comunitarie e interne. In tale prospettiva, viene evidenziato come la corporate governance delle banche e degli intermediari finanziari abbia progressivamente assunto tratti di specialità e sia sempre più caratterizzata in termini di risk governance
Smart Power Meter for the IoT
No full textAdvanced Metering Infrastructure (AMI) today represents the backbone of Smart City intended as urban area where the most of public services are smart. Smart devices allow cities to be smart, enabling communication also among things and creating a new system nowadays known as IoT (Internet of Things). In particular the smarter the meters, the smarter the City, but the concept of smartness is not univocal. In urban area, smart meters must be accessible, collaborative and accurate. The paper faces this topic, mainly with reference to power measurements and wireless networks. In particular, it describes an innovative solution for electrical power, gas and water metering integration in the same infrastructure. Then it describes metrics and hardware details of a smart electrical power meter and, finally it shows the experimental results of the smart meter metrological characterization
Preliminary Study on the Quality of Distributed Calibration Procedures for WSN
No full textNowadays, Wireless Sensor Networks are being used more and more widely. These are used to monitor various parameters, providing spatial and temporal information that cannot be obtained by using a single sensor node. Given the complexity of measurement, it is difficult to perform a spatially and temporally accurate calibration. One of the most widely used solutions is to include in WSNs some reference sensors with excellent metrological performance, which, however, has as its downside a high cost. The distributed calibration procedure, on the other hand, is based on periodic recalibration of sensor nodes with a single reference sensor. This paper will present a preliminary study on the inaccuracies and sources of uncertainty of this method and possible strategies for improving the quality of this technique by optimizing the placement of the reference sensor and the measurement time for calibration
Earthquake Early Detection as an IEEE1451 Transducer Network Trigger for Urban Infrastructure Monitoring and Protection
No full textThe occurrence of an earthquake has immediate consequences, such as the destruction of buildings. However, the impact can be much more severe and extend over time. The arrival of an earthquake's destructive wave can subsequently: produce a rupture in water distribution pipes, leading to water leakage, when water is even more valuable; break gas pipelines that will continue to lose gas and cause explosions leading to fires; cause the electrical power grid to come into contact with conductive structures, putting humans at risk of electrocution; or cause electrical discharges, which, in the presence of flammable materials, can give rise to fires. On the other hand, the storage of information collected by sensors that monitor the forces and deformations to which the building structure is subjected during the earthquake, allows engineers to know its state of health, right after the occurrence of the earthquake, making it possible to draw conclusions about the safety level of the building, not only for the immediate rescue, but also to execute the recovery and stabilization work [1], [2]
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