345 research outputs found
Wireless sensor systems with energy harvesting capabilities for safety enhancement in agricultural vehicles
This paper presents an overview of a multi-sensor wireless system applied to agricultural vehicles. The data provided by the different kinds of ad-hoc developed wireless sensors can be used as starting point for the implementation of an automatic system for the active safety enhancement of the vehicles. In order to guarantee a lifetime comparable with the one of the implement or trailer where they are mounted, each sensor has his own energy harvesting system able to gather energy from the vibrations occurring in the environment where the sensor operates
A 868MHz CMOS RF-DC Power Converter With -17dBm Input Power Sensitivity and Efficiency Higher Than 40% Over 14dB Input Power Range
In this paper we present a novel CMOS RF-DC converter circuit, operating at 868MHz, for RFID and remote powering applications. The novel reconfigurable architecture of the converter allows the circuit to operate over a very wide input power range with very high efficiency compared with previous art works. Prototypes realized in STM 0.130ìm CMOS technology provide a regulated output voltage ~2V with a -17dBm input power sensitivity. The circuit efficiency, higher than 40% over a 14dB input power range, peaks at 60%
Assessment and Mapping Green Areas Ecosystem Services and Socio-Demographic Characteristics in Turin Neighborhoods (Italy)
The ecosystem services (ES) and human well-being are keywords that guide the Italian strategy on urban greening. The development of ES priorities linked to specific land uses help to guide the drafting of management plans. The aim of the research was to assess and map green areas ecosystem services and socio-demographic characteristics in Turin neighborhoods in order to identify where to improve the provision of ecosystem services and the socio-demographic conditions. The Preliminary Assessment Method (PAM) was used for the assessment of provision and regulating services based on land use. The Species-specific Air Quality index (S-AQI) was used to assess the regulating services provided by trees. Three socio-demographic characteristics were analyzed at the neighborhood level—age index, housing density, and % of economically assisted citizens. PAM results show that Turin provides more ecosystem services in peripheral areas of the city. Trees with high S-AQI values represent 21% of the censed trees. Not recommended trees are 18%. The neighborhoods with higher S-AQI values are not always characterized by a higher number of trees/km2 or species richness. Results show that the northern part of the city is characterized by higher values of ES and socio-demographic conditions than the central-southern part. This aspect is related to the conspicuous presence of agricultural land uses and water bodies, together with the presence of tree species with a high S-AQI values and high or medium socio-demographic conditions. 57% of the neighborhoods present low results for both aspects. Actions to improve the quality of green spaces in those neighborhoods could have great effects on liveability. Future management and planning strategies for increasing citizens’ well-being through urban greening should consider the proposed approach
Reconfigurable RF Energy Harvester with Customized Differential PCB Antenna
In this work, a RF Energy harvester comprised of a differential RF-DC CMOS converter realized in ST130nm CMOS technology and a customized broadband PCB antenna with inductive coupling feeding is presented. Experimental results show that the system can work with different carrier frequencies and thanks to its reconfigurable architecture the proposed converter is able to provide a regulated output voltage of 2 V over a 14 dB of RF input power range. The conversion efficiency of the whole system peaks at 18% under normal outdoor working conditions
Integrated RF-DC converter and PCB antenna for UHF wireless powering applications
In this work, a broadband differential RF-DC CMOS converter realized in CMOS 130 nm technology with a customized PCB antenna with inductive coupling feeding for RF energy scavenging is presented. Experimental results show that output DC voltage higher than 1V from 800MHz to 970MHz can be obtained with a load of 1kohm
Force Impact Effect in Contact-Mode Triboelectric Energy Harvesters: Characterization and Modeling
In this paper we investigate the effect of the contact force on the voltage generated by Contact-Mode Triboelectric Energy Harvesting Devices (CM-TEHD). The electrical energy harvested from mechanical shocks increases with the contact force. In order to investigate the role of the contact force in the triboelectric energy generation, we developed a physical model, which allows understanding the physical mechanisms of this process, while predicting the output voltage and power at given conditions. Prototypes of the CM-TEHD made of low-cost commercial silicone were fabricated using a very low cost process. The prototypes provide up to 5.5µW when subjected to repetitive impacts with a contact force of 65N
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