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Using FieldSpec ® 4 Hi-Res portable coverings spectrometer, we have measured the main vegetation and siol reflectance based on different habitats:Surface water swamping meadow, a seasonal water swamping beach, wet beach without of water and sandy in the little Park Lake, East of the Qinghai Lake and analyzed the spectral differences. The results show that: Soil moisture is one of the important factors that affect reflectivity. Under the premise of similar other soil properties, soil moisture and reflectivity shows a negative correlation with each other. 350-1000nm wavelength range is ideal to distinguish vegetation and soil. Due to the presence of water absorption bands, within 1000-1300nm the spectrum derivative of soil and vegetation has a strong similarity, but still can be used to identify the spectrum of vegetation and soil. In addition to sandy habitats, vegetation and soil spectrum has a strong similarity in the 1300-2500nm wavelength range, it is more tolerance translation will confuse the two bands, the spectrum has a strong similarity in the range of 1300-2500nm, so it is relatively easy to confuse the two spectrum.

The article adopted the Jensen - Shannon Divergence analysis method for alpha wave EEG complexity analysis, used to quantify the three different status (Eyes closed, count, idle) degree of coupling between acquisition of EEG time series. The algorithm are used to calculate the statistical complexity of alpha wave EEG signals then T test, the results show that the state of eyes closed and idle under the coupling degree between EEG time series, and the state of eyes closed and counting, counting and daze cases EEG time series have significant differences. Thus JSD algorithm can be used to analyze EEG signals attention, statistical complexity can be used as a measure of brain function parameters and would be applied to the auxiliary clinical brain function evaluation in the future.

A semi-interpenetrating polymer network was fabricated from SMPU (Shape-Memory Polyureathan and PNIPAM (poly (N-isopropylacrylamide)) with the method of in-situ crosslinking polymerization. The temperature-sensitivity of the semi-IPN films was investigated and discussed. The morphology was achieved by extracting the SMPU phase. The influence of PNIPAM phase to the phase transition behavior of SMPU was studied with DSC, the results of which showing that the phase transition temperature is increased by PNIPAM. The introduction of PNIPAM also endows the semi-IPN films with a temperature-sensitive surface hydrophilicity, which was proved by water contact angle measurement at different temperatures. Finally, the water vapor permeability evaluation reveals the temperature-sensitive transportation property of the semi-IPN films, which is formed by the swelling and shrinking of PNIPAM phase according to the environmental temperature. These results shows that the semi-IPN material is a good candidate for the fabrication of intelligent breathable garments.

Current total variation method excels at denoising and keeping the characteristics of image edges. However, its ability to retain texture details of smoothing region of image is poor. By combining fractional-order differential theory with total variation method, a new image denoising method is proposed. The new method, while effectively inheriting these advantages, uses the fractional-order differential amplitude-frequency and effectively. Simulation results which we have got show that the new method, on the one hand, can better suppress noise, keep the characteristics of image edges, and retain more texture details than integer-order partial differential methods. On the other hand, the method, above mentioned, is more effective and practical on image denoising than results of PSNR.

The existing acoustic cover is improved to reduce the noise of G12V190 type diesel engine. A panel of shutters structure is designed and simulated with SYSNOISE. The structure of acoustic enclosure is also been designed according to the structure of the diesel engine. Theoretical calculation shows that the improved insulation cover has not only a good noise reduction effect, but also has been greatly improved in terms of cooling ventilation, the field test results also shows that this section of acoustic enclosure can reduce the noise about 10dB.

In this paper the diesel engine exhaust noise in petroleum well workplaces has been measured, the peak values scatters mainly in the low-frequency range, and the top value has reached 123dB. Based on transfer matrix method, this paper analyzes six kinds of silencing elements and establishes optimizing calculation procedure for diesel engine exhaust muffler. According to optimizing calculation procedure and exhaust noise frequency spectrum characteristic of diesel engine, we have designed a new large amount resistance muffler for G12V190 type diesel engine. After petroleum well scene experiment, the insertion loss of exhaust muffler has reached 33dB.

The triblock ABA copolymers of poly (D,L-lactide)-b-poly (ethylene glycol)-b-poly (D,L-lactide) (PDLLA-PEG-PDLLA) were synthesized by bulk ring-opening polymerization in the presence of N2 under normal pressure, using the D,L-lactide (DLLA) as monomer, hydroxyl endgroups of poly(ethylene glycol) (PEG) as initiator and the stannous octoate as the catalyst. The resulting copolymers were characterized by various analytical techniques. Effects of molar ratios of lactide to PEG and the chain length of PEG on the viscosity-average molecular weight of the copolymers, the biodegradation behaviors and hydrophilicity of the copolymers were investigated in detail. The results showed that the viscosity-average molecular weight and the contact angle of the copolymers increased with the molar ratio of lactide to PEG, but water uptake and degradability decreased.

In order to improve the hydrophilicity of poly (D,L-latide) (PDLLA), a novel amphiphilic ABA-type triblock copolymers of poly-N-vinylpyrrolidone (A) and poly (D, L-lactide) (B), were successfully synthesized by atom transfer radical polymerization (ATRP) using N-vinylpyrrolidone (VP) as monomer, bromide-terminated poly (D,L-latide) oligomer (Br-PDLLA-Br) as functional macromolecular initiator which was prepared when hydroxy-terminated poly(D,L-latide) oligomer (HO-PDLLA-OH) reacted with 2-bromopropanoyl bromide, CuBr/2,2’-bipyridine complex as the catalyst system. The resulting copolymers were characterized by various analytical techniques. The results showed that the introduction of poly (N-vinylpyrrolidone) (PVP) segments into polylactide enhanced the surface hydrophilicity of the copolymers remarkably and amphiphilic polymer can self-assemble into core-shell structure (polymer micelle) in water by the balance of the hydrophilic and hydrophobic interaction.