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This paper investigates the bistability of curved compression ramp (CCR) flows. It reports that both separated and attached states can be stably established even for the same boundary conditions, revealing that the ultimate stable states of CCR flows also depend on the initial conditions and evolutionary history. Firstly, we design a thought experiment involving two establishment routes of CCR flows, constructing two distinct-different stable states, respectively. Subsequently, three-dimensional direct numerical simulations are meticulously performed to instantiate the thought experiment, verifying the existence of the bistable states. Finally, we compare the pressure, wall friction, and heat flux distributions under two stable states. As a canonical type of Shock wave-Boundary layer interactions, local CCR flows often appear on aircraft, hence the bistability will certainly bring noteworthy changes to the global aerothermodynamic characteristics, which supersonic/hypersonic flight has to deal with.

For the HLS-II bunch current measurement system, in order to obtain the absolute value of bunch current, the calibration factor should be determined by using DCCT. At the HLS storage ring, the stretch effect of bunch length is observed and the change rate is about 19% when the bunch current decays over time and this will affect the performance of bunch current detection. To overcome the bunch stretch influence in the HLS-II bunch current measurement, an evaluation about pickup type and signal processing is carried out. Strip-line pickup and button pickup are selectable, and the theoretical analysis and demonstration experiment are performed to find out an acceptable solution for the bunch current measurement system at HLS-II. The experimental data analysis shows that the normalized calibration factor will change by about 27% when the bunch length change by about 19% if using the button pickup and processing by peak value of bunch signal, the influence will be reduced to less 2% if adopting the strip-line pickup and integral., Comment: 5 pages, 8 figures

The congestion pricing is an efficient allocation approach to mediate demand and supply of network resources. Different from the previous pricing using Affine Marginal Cost (AMC), we focus on studying the game between network coding and routing flows sharing a single link when users are price anticipating based on an Average Cost Sharing (ACS) pricing mechanism. We characterize the worst-case efficiency bounds of the game compared with the optimal, i.e., the price-of anarchy (POA), which can be low bound 50% with routing only. When both network coding and routing are applied, the POA can be as low as 4/9. Therefore, network coding cannot improve the POA significantly under the ACS. Moreover, for more efficient use of limited resources, it indicates the sharing users have a higher tendency to choose network coding., Comment: 5 pages,3 figures,Submitted to ICC 2012

We study how professional fund managers' growth expectations affect the actions they take with respect to equity investment and in turn the effects on prices. Using novel data on China's mutual fund managers' growth expectations, we show that pessimistic managers decrease equity allocations and shift away from more-cyclical stocks. We identify a strong short-run causal effect of growth expectations on stock returns, despite statistically significant delays in price discovery from short-sale constraints. Finally, we find that an earnings-based measure of price informativeness is increasing in fund investment. [ABSTRACT FROM AUTHOR]

Although many central banks in the 21st century have become more transparent, Chinese monetary policy communications have been relatively opaque, making it more difficult for financial market participants to make decisions that depend on the future path of interest rates. We conduct a novel systematic textual analysis of the discussion in the quarterly reports of China fund managers, from which we infer their near-term expectations for monetary policy. We construct an aggregate index of manager expectations and show that, as a forecast of Chinese monetary policy, it compares favorably with both market-based and model-based alternative projections. We find that expectations are more accurate for funds that commit more analytical resources, have higher management fees, and with stronger managerial educational background. We also show that fund managers act on these expectations, and that correctly anticipating shifts in Chinese monetary policy improves fund performance. Our results imply that manager skill is an important determinant of fund returns, providing the first evidence from China on a question for which studies of asset management in other countries have reached conflicting conclusions. economy. [ABSTRACT FROM AUTHOR]