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In aquatic ecosystems, pesticide residues meanly present as mixtures of varying complexity, which may lead to compound pollution of organisms. Therefore, it is of great practical importance to evaluate the combined toxic effects of pesticides. In this study, the mixture acute toxicities of fenvalerate with tebuconazole on zebrafish larvae and adults were investigated. The effects of mixture toxicity on swimming behavior of larvae were also analyzed. The mixture acute toxicity of the systems showed antagonistic effects on adult zebrafish when the mixing ratios of fenvalerate and tebuconazole were equal, but the other two ratios of the mixes both showed synergistic effects. The strongest synergistic effect was observed when fenvalerate was mixed with tebuconazole in the ratio of 8:2. The swimming behavior of zebrafish larvae was significantly inhibited after exposure to single or mixed systems for 2 days. However, significant up-regulation of behavioral indicators in zebrafish larvae was observed at the beginning of exposure in the mixture exposure groups. The results showed that fenvalerate and tebuconazole had the risk of synergistic toxic effect on zebrafish. It is recommended that the simultaneous use of both pesticides in agricultural activities near water bodies should be scientifically controlled to avoid adverse effects on aquatic organisms.

In this work a series of bamboo-derived biochars rich in micropores (its micropore ratio as high as 76%) were prepared by ZnCl2 chemical activation of bamboo processing residues, further modified with oxidation using concentrated HNO3, and characterized by N2 adsorption, XRD, Raman spectra, elemental analysis and Boehm titration. Their adsorptive desulfurization (ADS) performances were examined using dibenzothiophene from model fuels as an adsorbate. The results showed that the pore structure properties of these biochars are dominated by ZnCl2 chemical activation, the graphitization degrees are mainly governed by activation temperature, and the significantly increased surface acidic groups are primarily contributed from the HNO3 oxidation treatment. The biochar’s abundant micropore characteristic is an indispensable prerequisite for its good ADS performance, and also its high graphitization degree and surface acidic groups play important roles in improving ADS performance. Meanwhile, the optimized biochar can achieve an sulfur removal (%) of 96% with a selectivity close to 96%, its maximum adsorption amount and its breakthrough capacity reach 38.4 mg-S/g and 9.5 mg-S/g, respectively, and it shows much superior ADS performance to commercial activated carbon (AC) used in this work. Furthermore, the biochar can be reused for three times after regeneration without significant loss of ADS capacity. Thus, the biochar may become an excellent ADS adsorbent for production of clean fuel oils.

Intra Prediction is a good method to improve compression ratio. At present, Block as the basic prediction unit is adopted in prediction algorithm. The predict value of current point is searched and calculated from the adjacent point, its predictive result is closely related with the image features and the search process is very complexity. In the paper, a intra prediction method based image interpolation is proposed. First the original input image is divided into several sub-pictures, and one of sub-picture is encoded without predict process, and then the prediction frame of other sub-picture is calculated by interpolation processing of the first encoded sub-picture. In this algorithm, sub-picture as the basic prediction cell can be differential coded with reference frame. This algorithm has the advantage of high precision and low computation complexity. Combines with other coding method, the compression performance can be improved.

It is very consuming and non-intuitive, while we use 3D design software to design Three-dimensional human face model. How to solve the interaction problem and improve efficiency has become a problem bother animation designer. So a human-computer interactive device design system is given in this paper, this device consists of hardware and software component, which can implement press, pull and axial direction operation.

To satisfy the requirement of embedded video encoder in various scenarios, an embedded multi-channel video coding system based on multimedia processor-DM642 DSP is designed in this paper. For real-time application requirement, we optimize the encoder at three levels: Firstly, at algorithm level, develop some fast algorithm fitting for DSP; secondly, at system level, adjust the architecture of encoder and optimization data transfer with EDMA; thirdly, at code level, use linear assembly for key code. Experimental results show that the embedded video encoder can compress four channel CIF video data real-time.

The newest video coding standard H.264/AVC provides multiple reference frames motion estimation in the spatial region, and the optimal frame is selected by RDO (Rate Distortion Optimization) with high coding complexity. However, the coding efficiency only depends on the attribute of sequences, not on the number of reference frames. In this paper, statistical characteristics of the best reference frame with variable block size are studied, and a fast algorithm that takes into account the correlation is proposed. The reference frame of block mode may be chosen based on the computing result of the above block mode. Experimental results show that with similar Distortion performance, the algorithm can efficiently reduce the computational complexity by 19% averagely.

To satisfy the requirement of embedded video encoder in various scenarios, an embedded universal video coding system based on embedded processors is proposed in this paper, which combines the advantages of multi processors in single architecture. According to different channels, two feasible solutions are given to avoid the overflow and underflow of buffer while transmitting the compressed data. Due to limited computational resources and real-time application requirement, each module of the MPEG-4 codec is reviewed and efficiently implemented based on the embedded hardware platform. Experimental results show that the embedded system can successfully be used for real-time application.

Electromagnetic interference, shock and vibration under adverse conditions are critical problems for the design of embedded processing system, especially in the limited spaces. In addition, processing and transferring of large-scale image data are also important to the system. Therefore, in this paper an image data processing and storage system is designed, in which an ETX-CPU is used as the main module and a Virtex-II family FPGA acts as the processing core, at the same time, a well-appointed power processing circuit is designed to ensure the correctness of the system. In the end, CADENCE PCB layout design tools are used to solve the signal integrity problems of the system.