1,927 research outputs found
Reconfigurable Intelligent Surfaces for 6G -- Applications, Challenges and Solutions
It is expected that scholars will continuously strengthen the depth and
breadth of theoretical research on RIS, and provide a higher theoretical upper
bound for the engineering application of RIS. While making breakthroughs in
academic research, it has also made rapid progress in engineering application
research and industrialization promotion. This paper will provide an overview
of RIS engineering applications, and make a systematic and in-depth analysis of
the challenges and candidate solutions of RIS engineering applications. Future
trends and challenges are also provided.Comment: 2
Functional analysis of the micro/nanostructures of dragonfly wing veins
This article studies the internal micro/nanostructures and reveals the relations between the structures and functions of dragonfly wing veins. Through SEM, we take the microscopic photos of the cross-sections of dragonfly wing veins. From these photos, we obtain the following results: (a) The micro/nanostructures vary along the axis of the vein, i.e., different cross-sections have different micro/nanostructures. (b) For a given cross-section, the micro/nanostructures are of multilevels and multiscales. (c) At large scale, the structures of the veins are of diversities and disorders. The larger is the size scale. The more complicated are the structures, and the higher are the diversities and disorders. At small scale, the structures of the veins are of unifications and orders. The smaller is the size scale, the simpler is the structures, and the higher are the unifications and orders. (d) At the micro scale, we may induce unified assembling mode for the vein’s structures, i.e., “nanofibers/nanolayers (or nanobunches)”. (e) Both the mechanical functions and biological functions of the micro/nanostructures of the veins are optimized synthetically
Energy-Efficient Non-Orthogonal Transmission under Reliability and Finite Blocklength Constraints
This paper investigates an energy-efficient non-orthogonal transmission
design problem for two downlink receivers that have strict reliability and
finite blocklength (latency) constraints. The Shannon capacity formula widely
used in traditional designs needs the assumption of infinite blocklength and
thus is no longer appropriate. We adopt the newly finite blocklength coding
capacity formula for explicitly specifying the trade-off between reliability
and code blocklength. However, conventional successive interference
cancellation (SIC) may become infeasible due to heterogeneous blocklengths. We
thus consider several scenarios with different channel conditions and
with/without SIC. By carefully examining the problem structure, we present in
closed-form the optimal power and code blocklength for energy-efficient
transmissions. Simulation results provide interesting insights into conditions
for which non-orthogonal transmission is more energy efficient than the
orthogonal transmission such as TDMA.Comment: accepted by IEEE GlobeCom workshop on URLLC, 201
Shock-induced breaking of the nanowire with the dependence of crystallographic orientation and strain rate
The failure of the metallic nanowire has raised concerns due to its applied reliability in nanoelectromechanical system. In this article, the breaking failure is studied for the [100], [110], and [111] single-crystal copper nanowires at different strain rates. The statistical breaking position distributions of the nanowires have been investigated to give the effects of strain rate and crystallographic orientation on micro-atomic fluctuation in the symmetric stretching of the nanowires. When the strain rate is less than 0.26% ps-1, macro-breaking position distributions exhibit the anisotropy of micro-atomic fluctuation. However, when the strain rate is larger than 3.54% ps-1, the anisotropy is not obvious because of strong symmetric shocks
- …