4,701 research outputs found
GreenDelivery: Proactive Content Caching and Push with Energy-Harvesting-based Small Cells
The explosive growth of mobile multimedia traffic calls for scalable wireless
access with high quality of service and low energy cost. Motivated by the
emerging energy harvesting communications, and the trend of caching multimedia
contents at the access edge and user terminals, we propose a paradigm-shift
framework, namely GreenDelivery, enabling efficient content delivery with
energy harvesting based small cells. To resolve the two-dimensional randomness
of energy harvesting and content request arrivals, proactive caching and push
are jointly optimized, with respect to the content popularity distribution and
battery states. We thus develop a novel way of understanding the interplay
between content and energy over time and space. Case studies are provided to
show the substantial reduction of macro BS activities, and thus the related
energy consumption from the power grid is reduced. Research issues of the
proposed GreenDelivery framework are also discussed.Comment: 15 pages, 5 figures, accepted by IEEE Communications Magazin
Edge states induce boundary temperature jump in molecular dynamics simulation of heat conduction
We point out that the origin of the commonly occurred boundary temperature
jump in the application of No\'se-Hoover heat bath in molecular dynamics is
related to the edge modes, which are exponentially localized at the edge of the
system. If heat baths are applied to these edge regions, the injected thermal
energy will be localized thus leading to a boundary temperature jump. The jump
can be eliminated by shifting the location of heat baths away from edge
regions. Following this suggestion, a very good temperature profile is obtained
without increasing any simulation time, and the accuracy of thermal
conductivity calculated can be largely improved.Comment: accepted by PRB, brief report, references added, typo correcte
Liposome encapsulation of fluorescent nanoparticles: Quantum dots and silica nanoparticles
Quantum dots (QDs) and silica nanoparticles (SNs) are relatively new classes of fluorescent probes that overcome the limitations encountered by organic fluorophores in bioassay and biological imaging applications. We encapsulated QDs and SNs in liposomes and separated nanoparticle-loaded liposomes from unencapsulated nanoparticles by size exclusion chromatography. Fluorescence correlation spectroscopy was used to measure the average number of nanoparticles inside each liposome. Results indicated that nanoparticle-loaded liposomes were formed and separated from unencapsulated nanoparticles by using a Sepharose gel. As expected, fluorescence self-quenching of nanoparticles inside liposomes was not observed. Each liposome encapsulated an average of three QDs. These studies demonstrated that nanoparticles could be successfully encapsulated into liposomes and provided a methodology to quantify the number of nanoparticles inside each liposome by fluorescence correlation spectroscop
- …