Bioinspired Multifunctional Anti-icing Hydrogel

The recent anti-icing strategies in the state of the art mainly focused on three aspects: inhibiting ice nucleation, preventing ice propagation, and decreasing ice adhesion strength. However, it is has proved difficult to prevent ice nucleation and propagation while decreasing adhesion simultaneously, due to their highly distinct, even contradictory design principles. In nature, anti-freeze proteins (AFPs) offer a prime example of multifunctional integrated anti-icing materials that excel in all three key aspects of the anti-icing process simultaneously by tuning the structures and dynamics of interfacial water. Here, inspired by biological AFPs, we successfully created a multifunctional anti-icing material based on polydimethylsiloxane-grafted polyelectrolyte hydrogel that can tackle all three aspects of the anti-icing process simultaneously. The simplicity, mechanical durability, and versatility of these smooth hydrogel surfaces make it a promising option for a wide range of anti-icing applications

The stochastic bifurcation behaviour of speculative financial markets

This paper establishes a continuous-time stochastic asset pricing model in a speculative financial market with fundamentalists and chartists by introducing a noisy fundamental price. By application of stochastic bifurcation theory, the limiting market equilibrium distribution is examined numerically. It is shown that speculative behaviour of chartists can cause the market price to display different forms of equilibrium distributions. In particular, when chartists are less active, there is a unique equilibrium distribution which is stable. However, when the chartists become more active, a new equilibrium distribution will be generated and become stable. The corresponding stationary density will change from a single peak to a crater-like density. The change of stationary distribution is characterized by a bimodal logarithm price distribution and fat tails. The paper demonstrates that stochastic bifurcation theory is a useful tool in providing insight into various types of financial market behaviour in a stochastic environment. © 2008 Elsevier Ltd. All rights reserved

Does the market maker stabilize the market?

The market maker plays an important role in price formation, but his/her behavior and stabilizing impact on the market are relatively unclear, in particular in speculative markets. This paper develops a financial market model that examines the impact on market stability of the market maker, who acts as both a liquidity provider and an active investor in a market consisting of two types of boundedly rational speculative investors-the fundamentalists and trend followers. We show that the market maker does not necessarily stabilize the market when he/she actively manages the inventory to maximize profits, and that rather the market maker's impact depends on the behavior of the speculators. Numerical simulations show that the model is able to generate outcomes for asset returns and market inventories that are consistent with empirical findings. © 2009

Effect of iron content and potassium substitution in A0.8_{0.8}Fe1.6_{1.6}Se2_2 (A = K, Rb, Tl) superconductors: a Raman-scattering investigation

We have performed Raman-scattering measurements on high-quality single crystals of the superconductors K$_{0.8}$Fe$_{1.6}$Se$_2$ ($T_c$ = 32 K), Tl$_{0.5}$K$_{0.3}$Fe$_{1.6}$Se$_2$ ($T_c$ = 29 K), and Tl$_{0.5}$Rb$_{0.3}$Fe$_{1.6}$Se$_2$ ($T_c$ = 31 K), as well as of the insulating compound KFe$_{1.5}$Se$_2$. To interpret our results, we have made first-principles calculations for the phonon modes in the ordered iron-vacancy structure of K$_{0.8}$Fe$_{1.6}$Se$_2$. The modes we observe can be assigned very well from our symmetry analysis and calculations, allowing us to compare Raman-active phonons in the AFeSe compounds. We find a clear frequency difference in most phonon modes between the superconducting and non-superconducting potassium crystals, indicating the fundamental influence of iron content. By contrast, substitution of K by Tl or Rb in A$_{0.8}$Fe$_{1.6}$Se$_2$ causes no substantial frequency shift for any modes above 60 cm$^{-1}$, demonstrating that the alkali-type metal has little effect on the microstructure of the FeSe layer. Several additional modes appear below 60 cm$^{-1}$ in Tl- and Rb-substituted samples, which are vibrations of heavier Tl and Rb ions. Finally, our calculations reveal the presence of "chiral" phonon modes, whose origin lies in the chiral nature of the K$_{0.8}$Fe$_{1.6}$Se$_2$ structure.Comment: 11 pages, 10 figures and 2 table

Object tracking in the presence of shaking motions

© 2018, The Natural Computing Applications Forum. Visual tracking can be particularly interpreted as a process of searching for targets and optimizing the searching. In this paper, we present a novel tracker framework for tracking shaking targets. We formulate the underlying geometrical relevance between a search scope and a target displacement. A uniform sampling among the search scopes is implemented by sliding windows. To alleviate any possible redundant matching, we propose a double-template structure comprising of initial and previous tracking results. The element-wise similarities between a template and its candidates are calculated by jointly using kernel functions which provide a better outlier rejection property. The STC algorithm is used to improve the tracking results by maximizing a confidence map incorporating temporal and spatial context cues about the tracked targets. For better adaptation to appearance variations, we employ a linear interpolation to update the context prior probability of the STC method. Both qualitative and quantitative evaluations are performed on all sequences that contain shaking motions and are selected from the OTB-50 challenging benchmark. The proposed approach is compared with and outperforms 12 state-of-the-art tracking methods on the selected sequences while running on MATLAB without code optimization. We have also performed further experiments on the whole OTB-50 and VOT 2015 datasets. Although the most of sequences in these two datasets do not contain motion blur that this paper is focusing on, the results of our method are still favorable compared with all of the state-of-the-art approaches

Projections of motor vehicle growth, fuel consumption and CO{sub 2} emissions for the next thirty years in China.

Since the early 1990s, China's motor vehicles have entered a period of fast growth resultant from the rapid economic expansion. As the largest developing country, the fast growth of China's motor vehicles will have tremendous effects on the world's automotive and fuel market and on global CO{sub 2} emissions. In this study, we projected Chinese vehicle stocks for different vehicle types on the provincial level. First, we reviewed the historical data of China's vehicle growth in the past 10 years and the correlations between vehicle growth and economic growth in China. Second, we investigated historical vehicle growth trends in selected developed countries over the past 50 or so years. Third, we established a vehicle growth scenario based on the historical trends in several developed nations. Fourth, we estimated fuel economy, annual mileage and other vehicle usage parameters for Chinese vehicles. Finally, we projected vehicle stocks and estimated motor fuel use and CO{sub 2} emissions in each Chinese province from 2000 to 2030. Our results show that China will continue the rapid vehicle growth, increase gasoline and diesel consumption and increased CO{sub 2} emissions in the next 30 years. We estimated that by year 2030, Chinese motor vehicle fuel consumption and CO{sub 2} emissions could reach the current US levels