Li Y, Wang Y, Wang S, Ma S. An adaptative bitrate algorithm for DASH, in 2016 IEEE International Conference on Multimedia & Expo Workshops, ICME Workshops 2016, Seattle, WA, USA, July 11-15, 2016.; 2016:1–4. 访问链接
As a phase space language for quantum mechanics, the Wigner function approach bears a close analogy to classical mechanics and has been drawing growing attention, especially in simulating quantum many-body systems. However, deterministic numerical solutions have been almost exclusively confined to one-dimensional one-body systems and few results are reported even for one-dimensional two-body problems. This paper serves as the first attempt to solve the time-dependent many-body Wigner equation through a grid-based advective-spectral-mixed method. The main feature of the method is to resolve the linear advection in $(\bm{x},t)$-space by an explicit three-step characteristic scheme coupled with the piecewise cubic spline interpolation, while the Chebyshev spectral element method in $\bm k$-space is adopted for accurate calculation of the nonlocal pseudo-differential term. Not only the time step of the resulting method is not restricted by the usual CFL condition and thus a large time step is allowed, but also the mass conservation can be maintained. In particular, for the system consisting of identical particles, the advective-spectral-mixed method can also rigorously preserve physical symmetry relations. The performance is validated through several typical numerical experiments, like the Gaussian barrier scattering, electron-electron interaction and a Helium-like system, where the third-order accuracy against both grid spacing and time stepping is observed.
The aggregation behavior of 9, 36, and 112 nm hematite particles was studied in the presence of OmcA, a bacterial extracellular protein, in aqueous dispersions at pH 5.7 through time-resolved dynamic light scattering, electrophoretic mobility, and circular dichroism spectra, respectively. At low salt concentration, the attachment efficiencies of hematite particles in all sizes first increased, then decreased, and finally remained stable with the increase of OmcA concentration, indicating the dominant interparticle interaction changed along with the increase in the protein-to-particle ratio. Nevertheless, at high salt concentration, the attachment efficiencies of all hematite samples gradually decreased with increasing OmcA concentration, which can be attributed to increasing steric force. Additionally, the aggregation behavior of OmcA–hematite conjugates was more correlated to total particle–surface area than primary particle size. It was further established that OmcA could stabilize hematite nanoparticles more efficiently than bovine serum albumin (BSA), a model plasma protein, due to the higher affinity of OmcA to hematite surface. This study highlighted the effects of particle properties, solution conditions, and protein properties on the complicated aggregation behavior of protein–nanoparticle conjugates in aqueous environments.
As part of the 12th Five-Year Plan, the Chinese government has developed air pollution prevention and control plans for key regions with a focus on the power, transport, and industrial sectors. Here, we investigate the contribution of residential emissions to regional air pollution in highly polluted eastern China during the heating season, and find that dramatic improvements in air quality would also result from reduction in residential emissions. We use the Weather Research and Forecasting model coupled with Chemistry to evaluate potential residential emission controls in Beijing and in the Beijing, Tianjin, and Hebei (BTH) region. In January and February 2010, relative to the base case, eliminating residential emissions in Beijing reduced daily average surface PM2.5 (particulate mater with aerodynamic diameter equal or smaller than 2.5 micrometer) concentrations by 14 +/- 7 mu g.m(-3) (22 +/- 6% of a baseline concentration of 67 +/- 41 mu g.m(-3); mean +/- SD). Eliminating residential emissions in the BTH region reduced concentrations by 28 +/- 19 mu g.m(-3) (40 +/- 9% of 67 +/- 41 mu g.m(-3)), 44 +/- 27 mu g.m(-3) (43 +/- 10% of 99 +/- 54 mu g.m(-3)), and 25 +/- 14 mu g.m(-3) (35 +/- 8% of 70 +/- 35 mu g.m(-3)) in Beijing, Tianjin, and Hebei provinces, respectively. Annually, elimination of residential sources in the BTH region reduced emissions of primary PM2.5 by 32%, compared with 5%, 6%, and 58% achieved by eliminating emissions from the transportation, power, and industry sectors, respectively. We also find air quality in Beijing would benefit substantially from reductions in residential emissions from regional controls in Tianjin and Hebei, indicating the value of policies at the regional level.
As part of the 12th Five-Year Plan, the Chinese government has developed air pollution prevention and control plans for key regions with a focus on the power, transport, and industrial sectors. Here, we investigate the contribution of residential emissions to regional air pollution in highly polluted eastern China during the heating season, and find that dramatic improvements in air quality would also result from reduction in residential emissions. We use the Weather Research and Forecasting model coupled with Chemistry to evaluate potential residential emission controls in Beijing and in the Beijing, Tianjin, and Hebei (BTH) region. In January and February 2010, relative to the base case, eliminating residential emissions in Beijing reduced daily average surface PM2.5 (particulate mater with aerodynamic diameter equal or smaller than 2.5 micrometer) concentrations by 14 +/- 7 mu g.m(-3) (22 +/- 6% of a baseline concentration of 67 +/- 41 mu g.m(-3); mean +/- SD). Eliminating residential emissions in the BTH region reduced concentrations by 28 +/- 19 mu g.m(-3) (40 +/- 9% of 67 +/- 41 mu g.m(-3)), 44 +/- 27 mu g.m(-3) (43 +/- 10% of 99 +/- 54 mu g.m(-3)), and 25 +/- 14 mu g.m(-3) (35 +/- 8% of 70 +/- 35 mu g.m(-3)) in Beijing, Tianjin, and Hebei provinces, respectively. Annually, elimination of residential sources in the BTH region reduced emissions of primary PM2.5 by 32%, compared with 5%, 6%, and 58% achieved by eliminating emissions from the transportation, power, and industry sectors, respectively. We also find air quality in Beijing would benefit substantially from reductions in residential emissions from regional controls in Tianjin and Hebei, indicating the value of policies at the regional level.
