Sensitivity and Asymptotic Analysis of Inter-Cell Interference Against Pricing for Multi-Antenna Base Stations

We thoroughly investigate the downlink beamforming problem of a two-tier network in a reversed time-division duplex system, where the interference leakage from a tier-2 base station (BS) toward nearby uplink tier-1 BSs is controlled through pricing. We show that soft interference control through the pricing mechanism does not undermine the ability to regulate interference leakage while giving flexibility to sharing the spectrum. Then, we analyze and demonstrate how the interference leakage is related to the variations of both the interference prices and the power budget. Moreover, we derive a closed-form expression for the interference leakage in an asymptotic case, where both the charging BSs and the charged BS are equipped with a large number of antennas, which provides further insights into the lowest possible interference leakage that can be achieved by the pricing mechanism

Systemic lupus erythematosus (SLE) is associated with telomerase activation

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High fundamental-repetition-rate bound solitons in carbon nanotube-based fiber lasers

© 2015 IEEE.We demonstrate bound solitons formation with a high fundamental-repetition-rate of 211.8 MHz from an all-fiber linear-configuration mode-locked laser incorporating a carbon-nanotube-based saturable absorber for the first time. By adjusting the polarization state of laser cavity, bound solitons exhibit a large change of pulse separation in a range of 3.5-73 times longer than the pulsewidth, while the phase difference of the tightly bound solitons switches between pm π 2. Numerical simulations confirm the experimental observations about the dependence of spectral profile of bound solitons on the pulse separation and the phase difference

Operation-Switchable Bidirectional Pulsed Fiber Laser Incorporating Carbon-Nanotube-Based Saturable Absorber

© 1995-2012 IEEE.We present an operation-switchable bidirectional ring-cavity pulsed fiber laser incorporating a carbon-nanotube-based saturable absorber and a polarization-dependent four-port circulator. By manipulating the intra-cavity polarization state of light, two sets of mode-locked pulses in terms of fundamental repetition rate and pulse width can be achieved separately from the same laser cavity. In clockwise direction, the laser generates mode-locked output pulse train with a pulse width of 600 fs and a fundamental repetition rate of 12.68 MHz. While in counter-clockwise direction, the laser generates mode-locked pulses with a pulse width of 480 fs and a fundamental repetition rate of 16.46 MHz. Furthermore, the same laser cavity can produce bidirectional Q-switched output pulse trains with synchronized repetition rate. Such synchronized repetition rate is linearly proportional to pump power. The results show a multi-functional pulsed fiber laser with selectable output pulse trains

On the aerodynamic characteristics over idealized two-dimensional urban street canyon models

There are numerous anthropogenic pollutant sources in the atmospheric boundary layer (ABL) nowadays, which mainly attributed to human activities in urban areas. Hence, how urban morphology affects the heat and mass transfer in built environment is a popular research problem in the urban climate community. However, our understanding of street-level transport processes is rather limited. Laboratory experiments often serve as complementary solutions to modeling results. Although there are laboratory results available for the mass transfer over idealized urban roughness, the transport processes are not examined in de…published_or_final_versio

Laboratory measurements of local mass transfer coefficients over idealized two-dimensional urban street canyon models

postprintThe 2011 General Assembly of the European Geosciences Union (EGU), Vienna, Austria, 3-8 April 2011. In Geophysical Research Abstracts, 2011, v. 13, EGU2011-201

Enhanced stability of dispersion-managed mode-locked fiber lasers with near-zero net cavity dispersion by high-contrast saturable absorbers

We experimentally investigate the stability of dispersion-managed mode-locked fiber lasers using carbon-nanotubebased saturable absorbers (SAs) with different modulation depths. An unstable operation region of the mode-locked fiber laser with near-zero net cavity dispersion is observed, where the laser produces random pulse burst rather than stable pulse train. Through the implementation of high-contrast SAs in the laser, the unstable region is found to be shrunk by ?31.3% when the modulation depth of the SAs increases from 6.4% to 12.5%. The numerical simulation is consistent with the experimental observation. © 2013 Optical Society of America