Live video streaming service with pay-as-you-use model on Ethereum Blockchain and InterPlanetary file system

Wireless Networks - In centralized video streaming platforms, the platform owner, rather than the content producer, controls most of the content uploaded on the centralized video...     

Femtocells [Guest Editorial]

Femtocells are destined to transform the way mobile operators build their cellular networks and grow their coverage and capacity. Femtocells are small base stations operating in the licensed cellular bands. They are so small and inexpensive, and transmit at such low power, that they are meant to be placed in individual homes and backhauled onto the operator?s network via conventional digital subscriber line (DSL) or cable broadband access (or, when available, fiber).     

Femtocells [Guest Editorial]

Momentum is building rapidly around femtocells, as several operators worldwide have commercially launched 3G femtocells. This will further accelerate during the course of 2010, with many more operators expected to deploy. As explained in the first part of this series, which appeared in the September 2009 issue of IEEE Communications Magazine, femtocells are small, inexpensive base stations operating in the licensed cellular bands; they are meant to be placed in individual homes or businesses, and backhauled onto the operator's network via wireline broadband access.     

Gastric pneumatosis associated with preduodenal portal vein, duodenal atresia, and asplenia

An 8-day-old newborn presented with non-bilious vomiting, upper abdominal fullness, and failure to pass meconium. Plain radiographs revealed gastric pneumatosis (GP). At operation, he was found to have a non-obstructive preduodenal portal vein, preampullary duodenal atresia, asplenia, and malrotation. The baby was treated by duodeno-duodenostomy without mobilizing the portal vein and correction of the malrotation according to Ladd's procedure. He made an uneventful recovery and the GP resolved spontaneously. The malformative process was believed to have occurred at or soon after the 5th week of gestation, and the GP probably resulted from intramural air tracking through mucosal tears caused by high intragastric pressure.     

Effect of dopants on the low temperature microwave dielectric properties of Ba(Zn1/3Ta2/3)O3 ceramics

Ba(Zn_1/3Ta_2/3)O₃ has been prepared with different dopants that gave best microwave dielectric properties at room temperature. Effects of different dopants on the low temperature microwave dielectric properties of BZT were investigated. With decrease in temperature, loss tangent was found to decrease marginally and then increase at temperatures lower than 100 K. Increase in loss factor at lower temperatures were found to be less for dopants with smaller ionic radii. Dielectric constant was found to be almost independent of temperature. Temperature coefficient of resonant frequency slowly decreased from a positive value to negative value when temperature was lowered. Temperature at which τ_f becomes zero was found to vary for different dopants. There is a temperature stable region for tanδ, ɛ_r and τ_f which varies for different dopants.     

A large solid-angle array for heavy ions from APEX

A large solid-angle array of Low Pressure Multi-Wire Proportional Counters (LPMWPCs) has been constructed as part of the ATLAS Positron Experiment (APEX). Eight three-element trapezoidal counters span 360° in φ and 20–68° in laboratory θ. Angle sensitivity in θ is provided by a transmission-line delay cathode, while the 24-fold segmentation provides angle sensitivity in φ. Details are given on the design of the counters and associated hardware. Performance of the counters is described, based on tests with scattered heavy ions ranging from ⁵⁸Ni to ²³⁸U.     

Correlating Nanocrystalline Structure with Electronic Properties in 2D Platinum Diselenide

Platinum diselenide (PtSe₂) is a 2D material with outstanding electronic and piezoresistive properties. The material can be grown at low temperatures in a scalable manner, which makes it extremely appealing for many potential electronics, photonics, and sensing applications. Here, the nanocrystalline structure of different PtSe₂ thin films grown by thermally assisted conversion (TAC) is investigated and is correlated with their electronic and piezoresistive properties. Scanning transmission electron microscopy for structural analysis, X-ray photoelectron spectroscopy (XPS) for chemical analysis, and Raman spectroscopy for phase identification are used. Electronic devices are fabricated using transferred PtSe₂ films for electrical characterization and piezoresistive gauge factor measurements. The variations of crystallite size and their orientations are found to have a strong correlation with the electronic and piezoresistive properties of the films, especially the sheet resistivity and the effective charge carrier mobility. The findings may pave the way for tuning and optimizing the properties of TAC-grown PtSe₂ toward numerous applications.