Search results for "Wire"

Electrosynthesis of Sn-Co nanowires in alumina membranes

2010

A fabrication process of amorphous nanowires of Sn-Co alloys, based on electrodeposition into anodic alumina membranes, is described. It is shown that nanowires of tin-cobalt alloys with different compositions can be produced by varying electrodeposition time and concentration ratio of salts dissolved into the electrolytic bath. Importance of the chelating agent to produce amorphous Sn-Co alloys has also been addressed. Electrodepositions were carried out potentiostatically at -1 V versus Saturated Calomel Electrode and 60 degrees C for times ranging from 10 to 90 minutes; the atomic fraction of Co2+ in the aqueous electrolyte (Co2+/(Co2+ + Sn2+)) was varied from 0.33 to 0.67. Nanowires asp…

Blind Radio Tomography

2018

From the attenuation measurements collected by a network of spatially distributed sensors, radio tomography constructs spatial loss fields (SLFs) that quantify absorption of radiofrequency waves at each location. These SLFs can be used for interference prediction in (possibly cognitive) wireless communication networks, for environmental monitoring or intrusion detection in surveillance applications, for through-the-wall imaging, for survivor localization after earthquakes or fires, etc. The cornerstone of radio tomography is to model attenuation as the bidimensional integral of the SLF of interest scaled by a weight function. Unfortunately, existing approaches (i) rely on heuristic assumpti…

Evolution of topological superconductivity by orbital-selective confinement in oxide nanowires

2019

We determine the optimal conditions to achieve topological superconducting phases having spin-singlet pairing for a planar nanowire with finite lateral width in the presence of an in-plane external magnetic field. We employ a microscopic description that is based on a three-band electronic model including both the atomic spin-orbit coupling and the inversion asymmetric potential at the interface between oxide band-gap insulators. We consider amplitudes of the pairing gap, spin-orbit interactions and electronic parameters that are directly applicable to nanowires of LaAlO$_3$-SrTiO$_3$. The lateral confinement introduces a splitting of the $d$-orbitals that alters the orbital energy hierarch…

2021

Preamble Sampling MAC Protocol for Low Power Wireless Sensor Networks with IEEE 802.15.4 Transceivers

2006

In this paper a preamble sampling MAC protocol for low power wireless sensor networks is proposed. The article describes the implementation of the protocol using network nodes equipped with the Chipcon CC2420 802.15.4 transceiver. The power consumption of the transceiver has been measured and the MAC protocol has been adapted to the transceiver properties. The results show the trade-off between power consumption and transmission delay for this algorithm during the communication process.

A Battery-free Asset Monitoring System based on RF Wireless Power Transfer

2020

In the Internet of Things (IoT) era, asset monitoring represents an appealing implementation of Wireless Sensor Networks due to the enormous benefits associated with being able to monitor and record the exact position and transportation conditions of assets, personal objects, and the like. This kind of infrastructure enables the provision of increasingly advanced services, including the ability to measure the movement speed of a monitored asset using relatively inexpensive nodes with sensing capabilities and wireless transmission and reception. These nodes would ideally employ battery-free sensors that do not require any maintenance, but conventional power supply management systems cannot s…

Inductive Power Transfer for 100W battery charging

2013

Today, Inductive Power Transfer (IPT) is widely investigated to provide wireless battery charge. Potential applications range from a few Watts of handheld devices to kWatts of automotive applications. Despite of comfort and safety options, wireless charging features relatively poor power conversion efficiency. In the literature, several solutions are proposed addressing efficiency related issues. In this paper, a 100W wireless charging station for electric bikes which improves the power conversion efficiency is proposed. The magnetic structure design is analyzed thoroughly as well as the proposed power electronics system architectures of both the power transmitter and power receiver. The ef…

Surface Defects as a Tool to Solubilize and Functionalize WS 2 Nanotubes

2017

Layered transition metal dichalcogenides contain a number of crystal defects which significantly change their properties may be beneficial or detrimental for a specific application. We have prepared defect-rich multiwalled WS2 nanotubes by reductive sulfidization of W18O49 nanowires that were obtained solvothermally from tungsten chloride in different alcohols. The synthesis of the W18O49 nanowires was monitored and their morphological characteristics (e. g. length, rigidity and aspect ratio) are described in detail. The effect of morphology of the nanowires on the synthesis of WS2 nanotubes was investigated in order to obtain WS2 nanotubes that are highly solvent dispersible. Dispersions o…

Design and Fabrication of Terahertz Bragg Gratings on a Two-Wire Waveguide

In this study, we present the design and the fabrication procedure of waveguide-integrated Bragg Gratings operating at THz frequencies.

Design and Fabrication of Terahertz Metallic Gratings on a Two-Wire Waveguide

In this study, we present the design, fabrication and experimental characterization of waveguide-integrated gratings operating at THz frequencies