Body-UAV Near-Ground LoRa Links through a Mediterranean Forest

LoRa low-power wide-area network protocol has recently gained attention for deploying ad-hoc search and rescue (SaR) systems. They could be empowered by exploiting body-UAV links that enable communications between a body-worn radio and a UAV-mounted one. However, to employ UAVs effectively, knowledge of the signal's propagation in the environment is required. Otherwise, communications and localization could be hindered. The radio range, the packet delivery ratio (PDR), and the large- and small-scale fading of body-UAV LoRa links at 868 MHz when the radio wearer is in a Mediterranean forest are here characterized for the first time with a near-ground UAV having a maximum flying height of 30 m. A log-distance model accounting for the body shadowing and the wearer's movements is derived. Over the full LoRa radio range of about 600 m, the new model predicts the path loss (PL) better than the state-of-the-art ones, with a reduction of the median error even by 10 dB. The observed small-scale fading is severe and follows a Nakagami-m distribution. Extensions of the model for similar scenarios can be drawn through appropriate corrective factors

Preliminary functional results after transanal irrigation in patients undergoing SHiP procedure for low rectal cancer

The short-stump and high-anastomosis pull-through procedure (SHiP) is a newly introduced technique in the treatment of rectal cancer. This procedure does not involve the creation of a diverting ostomy with great improvement of the patients' quality of life in the post-operative period. However, functional post-operative alterations such as low anterior rectal resection syndrome (LARS) may occur. In this context, trans-anal irrigation (TAI) may represent a viable option in the treatment and management of LARS symptoms. The aim of the present study is to investigate the role of TAI in patients operated on SHiP procedure for low rectal cancer. A prospective database of 17 patients who underwent a SHiP procedure was maintained from April 2019 to December 2021. Anal continence and functional outcomes were assessed through LARS score and Cleveland Clinic Incontinence Score (CCIS), respectively. All patients with a LARS score > 21 underwent TAI in the post-operative period. LARS median value was 36 (IQR = 8) and drastically improved after TAI treatment to 3 (IQR = 3), as the CCIS at a mean follow-up of 9 months (SD +/- 5.02). Good functional result was reached in 12 out of 13 patients (92%). Our study confirms that patients with severe post-operative dysfunction could benefit from the use of TAI

modelling of acoustic ageing of rubberized pavements

Abstract Tyre-road noise is the most important source of traffic noise in the mid-to-high speed range. The use of low noise road surfaces represents an ideal solution to mitigate traffic noise, because it directly affects the source, generating a widespread benefit for all the dwellings near the road and decreasing the number of people annoyed. More knowledge about long-term acoustic performance is required to promote the use of low noise road surfaces as mitigation action. In fact, as for a traditional road surface, the acoustic properties of low noise surfaces worsen over time: only by knowing the initial noise reduction and its time evolution, public administrations can design their application and related maintenance plans. In this work, an innovative approach was used to investigate and model acoustic ageing of some rubberized road surfaces surveyed for several years. This type of quiet pavements represents an efficient road surface technology in terms of traffic noise reduction. A new regression model was applied to estimate the acoustic ageing of the investigated pavements, considering the complex interacting system composed of three main elements: pavement type, traffic loads and climatic conditions

Relationship between tyre cavity noise and road surface characteristics on low-noise pavements

Abstract In this work, a protocol to study Tyre Cavity Noise (TCN) was developed. Using this new method, TCN was measured on 24 different road pavements, together tyre noise emission measured with the Close-Proximity (CPX) method and road texture measurements. The results were used to model the relationship between TCN and road surface parameters. The analysis shows that the Standard Reference Test Tyre's (SRTT) TCN is correlated to megatexture at low frequencies and that the correlation between TCN and outside noise emission is significant for frequencies lower than 1 kHz. The use of sensors placed inside the tyre for monitoring the acoustic performance of road pavements presents several advantages compared to the CPX method, such as a more compact design, lower cost and lower hazards both for the instrumentation and for other vehicles

Influence of texture on tyre road noise spectra in rubberized pavements

Abstract Road traffic noise is the most common source of environmental pollution in urban areas and therefore, the study of noise mitigation actions is fundamental for urban planning. The main source of road traffic noise is tyre/road interaction; thus, the use of low noise road surfaces represents an optimal solution for its mitigation. Several studies tried to find a correlation between road texture and broadband noise data, trying to provide guidelines for the development of acoustically optimised road surfaces. The present work studies the correlation between road texture and tyre/road noise from an experimental point of view, by analysing texture and noise spectra on ten different road surfaces. Tyre deformation has also been addressed by analysing two already existing tyre envelopment algorithms. The first algorithm, proposed by Von Meier and based on the limitation of the second order derivative of the profile signal, shows poor correlation with high frequency noise, while the second algorithm, based on a novel method proposed by Sandberg and Goubert and called indenter method, enhances correlation with low frequency noise and preserves information at higher frequencies. Correlation patterns show that rolling noise can be separated in three main contributions: low, middle and high frequency noise. Finally, experimental tyre/road noise and enveloped texture data obtained with the indenter algorithm have been used to elaborate a linear model that relates low and high frequency noise to texture one-third octave bands. This model deepens knowledge on tyre/road interaction

Privacy-Aware Architectures for NFC and RFID Sensors in Healthcare Applications

World population and life expectancy have increased steadily in recent years, raising issues regarding access to medical treatments and related expenses. Through last-generation medical sensors, NFC (Near Field Communication) and radio frequency identification (RFID) technologies can enable healthcare internet of things (H-IoT) systems to improve the quality of care while reducing costs. Moreover, the adoption of point-of-care (PoC) testing, performed whenever care is needed to return prompt feedback to the patient, can generate great synergy with NFC/RFID H-IoT systems. However, medical data are extremely sensitive and require careful management and storage to protect patients from malicious actors, so secure system architectures must be conceived for real scenarios. Existing studies do not analyze the security of raw data from the radiofrequency link to cloud-based sharing. Therefore, two novel cloud-based system architectures for data collected from NFC/RFID medical sensors are proposed in this paper. Privacy during data collection is ensured using a set of classical countermeasures selected based on the scientific literature. Then, data can be shared with the medical team using one of two architectures: in the first one, the medical system manages all data accesses, whereas in the second one, the patient defines the access policies. Comprehensive analysis of the H-IoT system can be useful for fostering research on the security of wearable wireless sensors. Moreover, the proposed architectures can be implemented for deploying and testing NFC/RFID-based healthcare applications, such as, for instance, domestic PoCs

Volume Holographic Optical Elements as Solar Concentrators

In this chapter, we investigate the possibility to realize a holographic solar concentrator by using a new photopolymeric material as recording medium. Therefore, two different configurations of holographic lenses (lenses with spherical and cylindrical symmetry) are described in terms of both recording process and optical response characterization. Finally, we propose the possibility to use this new photopolymer to realize holographic solar concentrator for space applications

evaluation of tyre road noise and texture interaction on rubberised and conventional pavements using cpx and profiling measurements

Road traffic noise is the most common source of environmental pollution in urban areas, and therefore, the study of noise mitigation actions is fundamental for urban planning. The use of low noise ..

modelling the acoustic performance of newly laid low noise pavements

Abstract Road traffic in urban contexts produces noise mainly by the interaction of tyres with pavement surface and, therefore, the use of low-noise surfaces represents the best solution since they aim to mitigate the source. Moreover, in urban contexts it is often the only viable solution, together with a careful traffic planning. The main challenge in their adoption as noise mitigation actions is to be able to forecast the acoustical performances that the new road surface will be able to offer. In the UE, the new Green Public Procurement requires experimental verification of noise performance compliance: the designer must declare the acoustical performance of the proposed low-noise pavement and, a few months after the laying, the actual performance of the road surface must be tested using the Close Proximity Method (CPX). Due to the importance of being able to forecast CPX levels, the present work reports a novel way to model CPX broadband levels of newly laid low-noise road surfaces using only data available to the designer before the laying or easily obtained through coring tests, such as grading curve, fractal dimension, asphalt binder content, air voids, voids in mineral aggregates. Two models were elaborated, using two different frequency separations for tyre/road noise. The first model separates low and high frequency contributions, while the second one also considers noise around 1 kHz separately, using a three-band model. Both models are capable of forecasting the acoustic performance of newly laid low-noise road surfaces, using different road mixture parameters at different frequency ranges. The three band model shows a lower RMSE

Tariffs and non-tariff frictions in the world wine trade

This article empirically investigates the impact of trade barriers on the world wine trade, focusing on trade costs impeding exports, including transport, tariffs, technical barriers and sanitary and phytosanitarystandards. A gravity model is estimated using data from the main importing and exporting countries for the years 1997 to 2010. The Poison Pseudo-Maximum Likelihood (PPML) estimator accounts for heteroskedasticity and the presence of zero trade flows. Our results identify which regulations can adversely affect trade, providing useful information to policy-makers involved in negotiations on trade frictions. While sanitary and phytosanitary measures do not seem to obstruct exports, technical barriers have a varying impact on trade. A decreasing trend for tariffs has largely been compensated by more stringent technical barriers. The overall result is that frictions in the world wine trade have not changed during the past fifteen years