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Block and random polyhedral oligomeric silsesquioxane (POSS)/fluorinated poly aryl ether sulfone tricopolymers were synthesized using different synthetic strategies to investigate the effect of sequence distribution on their thermal, dielectric, and surface properties. Analyses indicated that all block and random copolymers showed similar growth tendency of water contact angles and Tg values, downward tendency of k values with increased content of POSS. The block copolymer displayed higher Tg values up to 187°C than random copolymers (173°C) under the same POSS molar percentage, which were highly related to their different sequence distribution. The dielectric constants of the tricopolymers were drastically reduced because of the presence of POSS and fluorine, and the dielectric constant could achieve as low as 2.71 (1 MHz). Besides, sequence distribution has no obvious influence on its surface properties and properties. Meanwhile, the yields of degradation residues of the tricopolymers were significantly improved by the ceramic formation from POSS moieties during thermal decomposition. Copyright © 2016 John Wiley & Sons, Ltd.

Breitung and Candelon (2006) in Journal of Econometrics proposed a simple statistical testing procedure for the noncausality hypothesis at a given frequency. In their paper, however, they reported some theoretical results indicating that their test severely suffers from quite low power when the noncausality hypothesis is tested at a frequency close to 0 or pi. This paper examines whether or not these results indicate their procedure is useless at such frequencies.

This paper investigates the dynamic relationships between oil prices and the Japanese economy from a frequency domain perspective. Both the frequency domain causality test of Breitung and Candelon (2006) and the frequency dependent regression method developed by Ashley and Verbrugge (2009) are deployed in this research. The frequency dependent regression analysis indicates that nonlinear relationships exist between oil prices and the variables such as industrial production and consumer price index at the low frequencies, while the nonlinear associations at the high frequencies are merely detected between oil prices and unemployment rates. The results of the frequency domain causality tests suggest that oil prices have significant predictive power for industrial production, consumer price index and unemployment rates at the low frequencies. In addition, oil prices can predict industrial production and unemployment rates at some higher frequencies.

It is well known that the results of remote sensing image classification contain many small isolated regions. These isolated regions need to be eliminated and merged into the existing classes in the post-processing. The most critical issue among all is how we could recognize the isolated regions, and what strategy we should adopt in automatic elimination. We present in this paper an algorithm for isolated regions' recognition based on connected area, in isolated region generation, we adopt an improved area filling algorithm in computer graphics. In automatic elimination, we propose a merge strategy which is based on the number of immediate pixels. Experimental results show that our recognition algorithm and merge strategy can effectively and automatically eliminate the isolated regions in the results of remote sensing image classification

The Cd-annealing effects on Cd 1-x Zn x Te wafers were studied by means of IR transmission and micro-Raman spectrum. The experiments and theoretical analysis demonstrated that the free carrier absorption related to the Cd vacancies resulted in the IR extinction as observed in the transmission spectra. The Raman spectra showed that Raman scattering is a more sensitive method to detect the fine Te precipitates in the Cd 1-x Zn x Te substrates. The Raman scattering peaks related to the Te precipitates could be found in both the as grown and the annealed samples. The relative intensity of the Te scattering peaks became weaker after Cd-annealing. This result also indicated that it was quite difficult to eliminate the fine Te precipitates entirely through annealing process.