This work reports the advanced potassium sodium niobate (K 0.5 Na 0.5 NbO 3 , KNN)/polyimide (KNN/PI) functional hybrid films with 5 vol%, 10 vol%, 20 vol%, 30 vol%, and 40 vol% KNN loaded. The structure, morphology, and dielectric properties of hybrid films have been measured. The results show that the KNN fillers are well dispersed in the PI matrix. An internal boundary layer capacitance structure is formed in the composite films. The dielectric permittivity of the film is as high as 22 when the concentration of KNN filler reaches 40 vol% at 10 2 Hz, which is five times larger than that of a pure PI matrix. Meanwhile, the loss tangent is lower than 0.05. In addition, the conductivity is lower than 10 28 (S m 21 ) at 10 2 Hz, which indicates the excellent insulation and is important for the practical use of this kind of KNN/PI hybrid films. It is believed that the KNN/PI hybrid films could be applied in future electronic fields. POLYM. COMPOS., 35:969-974, 2014.

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Polyimide (PI) films filled with K 0.5 Na 0.5 NbO 3 (KNN50) particles at different weight 0, 5, 10, and 15 wt % had been prepared by in-situ dispersion polymerization process. The thermally stimulated current (TSDC) method was used to investigate the charge carrier trap levels and their distribution of the composite films. The TSDC spectra show that pure film has a -peaks and bpeak, but the composite films only have a -peaks and an extraordinary peak at high temperature region. The trap parameters were calculated by an approximate model, and the results indicate that charge released of the shallow traps show a nonlinear behavior. The trap energies decrease from 0.879-0.968 eV to 0.549-0.839 eV with the increase of the KNN50 content. The surface and interface between KNN50 and PI matrix was considered to the variation of the trap levels. The extraordinary peak of the composite films was correlated with the phase transition of the KNN50 particles.

This paper presents the design and implementation of the FPGA-based web server for biological sequence alignment. Central to this web-server is a set of highly parameterisable, scalable, and platform-independent FPGA cores for biological sequence alignment. The web server consists of an HTML-based interface, a MySQL database which holds user queries and results, a set of biological databases, a library of FPGA configurations, a host application servicing user requests, and an FPGA coprocessor for the acceleration of the sequence alignment operation. The paper presents a real implementation of this server on an HP ProLiant DL145 server with a Celoxica RCHTX FPGA board. Compared to an optimized pure software implementation, our FPGA-based web server achieved a two order of magnitude speed-up for a pairwise protein sequence alignment application based on the Smith-Waterman algorithm. The FPGA-based implementation has the added advantage of being over 100x more energyefficient.

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