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1.
Sensors (Basel) ; 21(5)2021 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-33800073

RESUMO

The paper shows the steps for the preliminary studies of an AUV for shallow water: the first part illustrates the vehicle architecture and the philosophy that permeates the various design choices. In the second part illustrates an innovative method for increasing longitudinal stability based on Takagi-Sugeno (T-S) Fuzzy Inference System: it saves a lot of computational time and, by simplifying the calculation, it is also suitable for remarkably simple computers such as Arduino. in the third part is simulated the behavior of the AUV: thanks to the data taken from the previous hydrodynamic simulation, we can establish the behavior of its longitudinal stability and the computational savings due to the T-S method.

2.
Sensors (Basel) ; 20(17)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882926

RESUMO

The paper shows the simulation of the behavior of a swarm of underwater drones (AUV) diffused in a closed section of the sea and inserted from a single starting point: Based on a few essential rules, we will see how their behavior evolves and how they manage to spread throughout the area assigned to them. In the first part of this work, after defining the design of the vehicle, we introduce our vision of the swarm, its problems, and its strengths. Later, we show how to spread a series of underwater drones with "diffused intelligence" (swarm) and its microscopic diffusion model. In the last part, we present the simulation that supports our approach to the swarm.

3.
Sensors (Basel) ; 20(8)2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32316218

RESUMO

Underwater Optical Wireless Communication (UOWC) is not a new idea, but it has recently attracted renewed interest since seawater presents a reduced absorption window for blue-green light. Due to its higher bandwidth, underwater optical wireless communications can support higher data rates at low latency levels compared to acoustic and RF counterparts. The paper is aimed at those who want to undertake studies on UOWC. It offers an overview on the current technologies and those potentially available soon. Particular attention has been given to offering a recent bibliography, especially on the use of single-photon receivers.

4.
Phys Rev Lett ; 123(23): 230502, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868431

RESUMO

Introducing quantum sensors as a solution to real world problems demands reliability and controllability outside of laboratory conditions. Producers and operators ought to be assumed to have limited resources readily available for calibration, and yet, they should be able to trust the devices. Neural networks are almost ubiquitous for similar tasks for classical sensors: here we show the applications of this technique to calibrating a quantum photonic sensor. This is based on a set of training data, collected only relying on the available probe states, hence reducing overhead. We found that covering finely the parameter space is key to achieving uncertainties close to their ultimate level. This technique has the potential to become the standard approach to calibrate quantum sensors.

5.
Sensors (Basel) ; 19(8)2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999627

RESUMO

This paper is a section of several preliminary studies of the Underwater Drones Group of the Università degli Studi "Roma Tre" Science Department: We describe the study philosophy, the theoretical technological considerations for sizing and the development of a technological demonstrator of a high accuracy buoyancy and depth control. We develop the main requirements and the boundary conditions that design the buoyancy system and develop the mathematical conditions that define the main parameters.

6.
Sensors (Basel) ; 18(9)2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30235897

RESUMO

This paper focuses on the development of a new logistic approach based on reliability and maintenance assessment, with the final aim of establishing a more efficient interval for the maintenance activities for Unmanned Aerial Vehicles (UAV). In the first part, we develop an architectural philosophy to obtain a more detailed reliability evaluation; then, we study the intrinsic reliability at the design stage in order to avoid severe critical issues in the UAV. In the second part, we compare different maintenance philosophies for UAVs and develop the concepts of preventive and corrective maintenance that consider the system subjected (until real "hard failure") to partial performance degradation ("soft failure"). Finally, by evaluation of the uncertainty through the confidence interval, we determine the new soft failure limits, taking into account the general knowledge of the systems and subsystems in order to guarantee the proper preventive maintenance interval.

7.
Sensors (Basel) ; 14(12): 24408-24, 2014 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-25529206

RESUMO

A smart city application has been realized and tested. It is a fully remote controlled isle of lamp posts based on new technologies. It has been designed and organized in different hierarchical layers, which perform local activities to physically control the lamp posts and transmit information with another for remote control. Locally, each lamp post uses an electronic card for management and a ZigBee tlc network transmits data to a central control unit, which manages the whole isle. The central unit is realized with a Raspberry-Pi control card due to its good computing performance at very low price. Finally, a WiMAX connection was tested and used to remotely control the smart grid, thus overcoming the distance limitations of commercial Wi-Fi networks. The isle has been realized and tested for some months in the field.

8.
Sensors (Basel) ; 14(6): 9813-32, 2014 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-24901977

RESUMO

In this paper, we propose a new sensor for the detection and analysis of dusts (seen as powders and fibers) in indoor environments, especially designed for applications in the field of Cultural Heritage or in other contexts where the presence of dust requires special care (surgery, clean rooms, etc.). The presented system relies on image processing techniques (enhancement, noise reduction, segmentation, metrics analysis) and it allows obtaining both qualitative and quantitative information on the accumulation of dust. This information aims to identify the geometric and topological features of the elements of the deposit. The curators can use this information in order to design suitable prevention and maintenance actions for objects and environments. The sensor consists of simple and relatively cheap tools, based on a high-resolution image acquisition system, a preprocessing software to improve the captured image and an analysis algorithm for the feature extraction and the classification of the elements of the dust deposit. We carried out some tests in order to validate the system operation. These tests were performed within the Sistine Chapel in the Vatican Museums, showing the good performance of the proposed sensor in terms of execution time and classification accuracy.


Assuntos
Arte , Poeira/análise , Monitoramento Ambiental/métodos , Processamento de Imagem Assistida por Computador/métodos
9.
Sensors (Basel) ; 14(5): 9290-312, 2014 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-24859030

RESUMO

A new acquisition system for remote control of wall paintings has been realized and tested in the field. The system measures temperature and atmospheric pressure in an archeological site where a fresco has been put under control. The measuring chain has been designed to be used in unfavorable environments where neither electric power nor telecommunication infrastructures are available. The environmental parameters obtained from the local monitoring are then transferred remotely allowing an easier management by experts in the field of conservation of cultural heritage. The local acquisition system uses an electronic card based on microcontrollers and sends the data to a central unit realized with a Raspberry-Pi. The latter manages a high quality camera to pick up pictures of the fresco. Finally, to realize the remote control at a site not reached by internet signals, a WiMAX connection based on different communication technologies such as WiMAX, Ethernet, GPRS and Satellite, has been set up.


Assuntos
Monitoramento Ambiental/instrumentação , Umidade , Internet/instrumentação , Pinturas , Fotografação/instrumentação , Tecnologia de Sensoriamento Remoto/instrumentação , Termografia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Integração de Sistemas , Tecnologia sem Fio/instrumentação
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