4,715 research outputs found
Traffic eavesdropping based scheme to deliver time-sensitive data in sensor networks
Due to the broadcast nature of wireless channels, neighbouring sensor nodes may overhear packets transmissions from each other even if they are not the intended recipients of these transmissions. This redundant packet reception leads to unnecessary expenditure of battery energy of the recipients. Particularly in highly dense sensor networks, overhearing or eavesdropping overheads can constitute a significant fraction of the total energy consumption. Since overhearing of wireless traffic is unavoidable and sometimes essential, a new distributed energy efficient scheme is proposed in this paper. This new scheme exploits the inevitable overhearing effect as an effective approach in order to collect the required information to perform energy efficient delivery for data aggregation. Based on this approach, the proposed scheme achieves moderate energy consumption and high packet delivery rate notwithstanding the occurrence of high link failure rates. The performance of the proposed scheme is experimentally investigated a testbed of TelosB motes in addition to ns-2 simulations to validate the performed experiments on large-scale network
Radio-frequency methods for Majorana-based quantum devices: fast charge sensing and phase diagram mapping
Radio-frequency (RF) reflectometry is implemented in hybrid
semiconductor-superconductor nanowire systems designed to probe Majorana zero
modes. Two approaches are presented. In the first, hybrid nanowire-based
devices are part of a resonant circuit, allowing conductance to be measured as
a function of several gate voltages ~40 times faster than using conventional
low-frequency lock-in methods. In the second, nanowire devices are capacitively
coupled to a nearby RF single-electron transistor made from a separate
nanowire, allowing RF detection of charge, including charge-only measurement of
the crossover from 2e inter-island charge transitions at zero magnetic field to
1e transitions at axial magnetic fields above 0.6 T, where a topological state
is expected. Single-electron sensing yields signal-to-noise exceeding 3 and
visibility 99.8% for a measurement time of 1 {\mu}s
A Review of the Energy Efficient and Secure Multicast Routing Protocols for Mobile Ad hoc Networks
This paper presents a thorough survey of recent work addressing energy
efficient multicast routing protocols and secure multicast routing protocols in
Mobile Ad hoc Networks (MANETs). There are so many issues and solutions which
witness the need of energy management and security in ad hoc wireless networks.
The objective of a multicast routing protocol for MANETs is to support the
propagation of data from a sender to all the receivers of a multicast group
while trying to use the available bandwidth efficiently in the presence of
frequent topology changes. Multicasting can improve the efficiency of the
wireless link when sending multiple copies of messages by exploiting the
inherent broadcast property of wireless transmission. Secure multicast routing
plays a significant role in MANETs. However, offering energy efficient and
secure multicast routing is a difficult and challenging task. In recent years,
various multicast routing protocols have been proposed for MANETs. These
protocols have distinguishing features and use different mechanismsComment: 15 page
Scalable Microfabrication Procedures for Adhesive-Integrated Flexible and Stretchable Electronic Sensors.
New classes of ultrathin flexible and stretchable devices have changed the way modern electronics are designed to interact with their target systems. Though more and more novel technologies surface and steer the way we think about future electronics, there exists an unmet need in regards to optimizing the fabrication procedures for these devices so that large-scale industrial translation is realistic. This article presents an unconventional approach for facile microfabrication and processing of adhesive-peeled (AP) flexible sensors. By assembling AP sensors on a weakly-adhering substrate in an inverted fashion, we demonstrate a procedure with 50% reduced end-to-end processing time that achieves greater levels of fabrication yield. The methodology is used to demonstrate the fabrication of electrical and mechanical flexible and stretchable AP sensors that are peeled-off their carrier substrates by consumer adhesives. In using this approach, we outline the manner by which adhesion is maintained and buckling is reduced for gold film processing on polydimethylsiloxane substrates. In addition, we demonstrate the compatibility of our methodology with large-scale post-processing using a roll-to-roll approach
Interferometry using spatial adiabatic passage in quantum dot networks
We show that techniques of spatial adiabatic passage can be used to realise
an electron interferometer in a geometry analogous to a conventional
Aharonov-Bohm ring, with transport of the particle through the device modulated
using coherent transport adiabatic passage. This device shows an interesting
interplay between the adiabatic and non-adiabatic behaviour of the system. The
transition between non-adiabatic and adiabatic behaviour may be tuned via
system parameters and the total time over which the protocol is enacted.
Interference effects in the final state populations analogous to the
electrostatic Aharonov-Bohm effect are observed.Comment: Version accepted in Phys. Rev. B, 8 pages, 6 figure
Covert Quantum Internet
We apply covert quantum communication based on entanglement generated from
the Minkowski vacuum to the setting of quantum computation and quantum
networks. Our approach hides the generation and distribution of entanglement in
quantum networks by taking advantage of relativistic quantum effects. We devise
a suite of covert quantum teleportation protocols that utilize the shared
entanglement, local operations, and covert classical communication to transfer
or process quantum information in stealth. As an application of our covert
suite, we construct two prominent examples of measurement-based quantum
computation, namely the teleportation-based quantum computer and the one-way
quantum computer. In the latter case we explore the covert generation of graph
states, and subsequently outline a protocol for the covert implementation of
universal blind quantum computation.Comment: 9 pages, 2 figure
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