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Sparse representation is a new image representation theory. It can accurately represent the image information. In this paper, a novel fusion scheme using sparse representation is proposed. The sparse representation is conducted on overlapping patches. Each source image is divided into patches, and all the patches are transformed into vectors. Decompose the vectors into theirs sparse representations using orthogonal matching pursuit. Sparse coefficients are fused with the maximum absolute. The simulation results show that the proposed method can provide high-quality images.

An image fusion algorithm by combing Nonsubsampled Contourlet Transform and Pulse Coupled Neural Network is proposed in this paper. Two primitive matched images are decomposed in NSCT domain. The low frequency used the regional energy weighted fusion. The high frequency coefficients are input to the PCNN. Finally, the fused result is obtained through inverse NSCT. The novel algorithm will employ features and contain the most of the energy of image. The simulation results show that the results are much better than the experimental results, which the mutual information and QAB/F parameters are higher than the contrast method of fusion results.

A novel algorithm which is image fusion based on GPU is proposed. The fused rule is regional energy. In recent years, the power of the computing of GPU has been greatly improved, which results that using it for the general-purpose computing has a rapid development. The essay researches on implementing the oriental field algorithm on GPU, including selecting GPU memories and dividing blocks and threads of GPU kernel functions. The results of experiment on the GPU of NVIDIA GTX560 are given, which shows that our proposed algorithm can be applied to the field of image fusion. Experiment shows the proposed algorithm has faster calcu-lation velocity and higher evaluation accuracy. The speed of the parallel algorithm is 200 times faster than that of the CPU-based implementation. Meanwhile the mutual information and QAB/F parameters are higher than that of the CPU-based algorithm.

This paper briefly reviews our recent analytical and experimental results on 3 interrelated features beyond the peak load in heterogeneous media: continuous bifurcation, damage localization and catastrophic rupture (CR). Firstly, an Elastic Statistically-Brittle model (ESB) was introduced to formulate the basic features of a kind of heterogeneous media, like rocks and cements. The global mean field approximation (GMF) shows that the measure of heterogeneity, like the Weibull modulus m in the distribution of meso-strength plays a key role to distinguish CR from gradual failure. Then, with the ESB model and corresponding experimental results, continuous bifurcation and damage localization are discussed. In accord with these, regional mean field approximation (RMF) is adopted and it shows that any scale of damage localization can satisfy the conservation laws in continuum mechanics. This implies that catastrophic rupture could appear at any state beyond the peak load, depending on the unknown evolution of damage localization zone. Hence, catastrophic rupture seems to occur stochastically at macroscopic level. On the other hand, both experimental and analytic studies demonstrate that a robust power law singularity (-1/2) appears ahead of CR. Preliminary applications of these ideas are briefly described.

The extraction of flavonoids from clovers was optimized to maximize flavonoid yield Y in this study. A central composite design of response surface methodology involving extracting time, liquid-solid ratio, extracting temperature and ethanol concentration was used, and second-order model for Y was employed to generate the response surfaces. The optimum condition for Y was determined as follows: extracting time 24min, liquid-solid ratio 20, extracting temperature 80°C, and ethanol concentration 72%. Under the optimum condition, the flavonoid yield was 2.49%.

The polymer system in low interfacial tension conditions is a important technology in oilfield production. Through the Using both rheometer(HAAKE RS150) and interface tension instrument(TS500), the effect of interfacial tension character and viscosity caused by the changing of polymer mass concentration is studied in 30 degrees celsius condition. The man-made core displacement oil experiments and visual model displacement oil experiments were carried out, the displacement efficiency of polymer solution with low interfacial tension after water flooding or polymer flooding was analyzed. The results indicate that the interfacial tension between polymer system with low interfacial tension and oil first reduced, then increased with the increasing of polymer mass concentration, when the polymer mass concentration changes form 0.5gram/Litre to 1.5gram/Litre, the interfacial tension is 10-3 milli-Newton/meter order of magnitude, when the polymer mass concentration increased to 2.0gram/Litre, the interfacial tension is 10-2 milli-Newton/meter order of magnitude. With the changing the polymer mass concentration of polymer system from 0.5gram/Litre, 1.0gram/Litre and 2.0gram/Litre, the viscosity of polymer system with low interfacial tension increased obviously. The recovery ratio can be enhanced further by polymer solution with low interfacial tension after both water flooding and polymer flooding.

Through creep-recovery and dynamic experiments, the viscoelasticity of polyacrylamide solutions (in short polymer) with different mass concentration are studied, the proportions of elastic part and viscous part in the polymer solution are calculated and the limit of mass concentration called high concentration polymer solution is given. It is indicated that the elastic part of the polymer solution increases firstly and tends to be constant with the increase in mass concentration under low external force condition. The minimum mass concentration of the polymer solution keeping constant elastic part is 1500mg/L. Under low stress and low shear rate conditions, the viscous part of the polymer solution is greater than that of elastic part; but under oil reservoir shear rate (6.283s-1) condition, the elastic part is greater than viscous part, and its elastic part increases with the increase in mass concentrations and the increment becomes smaller.