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The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement. A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008. Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area. Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola. We fit the model of cotton water production on the basis of field experimental data of cotton. And the analysis on water saving Benefit of cotton under mulched drip irrigation was done. Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area. The water requirements of seedling stage is 252 mm, budding stage is 186 mm, bolling stage is 316 mm and wadding stage is 139 mm. the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle. However, water consumption at different growth stages was inconsistent with irrigation. Quantitatively, the water consumed by cotton decreases upon the increase of irrigation amount. From the perspective of water saving, the maximal water use efficiency can reach 3 091 m3/ha. But the highest cotton yield needs 3464 m3/ha irrigation water. In summary, compared to the conventional drip irrigation, a number of benefits in water saving and yield increase were observed when using plastic mulch. At the same amount of irrigation, the cotton yield with plastic mulch was 30.2% higher than conventional approaches, and the efficiency of water utilization increased by 30.2%. While at the same yield level, 29.3% water was saved by using plastic mulch, and the efficiency increased by 41.5%.

Marine radar image often has a lot of noise signal, the noise ratio of the radar image is very low. So a method based on a combination of wavelet transform, K-distributed sea clutter threshold segmentation and most of the interpolation repair method is presented in this paper, which can deal with the same frequency noise of marine radar image. This paper comes up with use wavelet transform to determine potential radar image noise level, then by adopting the method of threshold segmentation technique for marine radar information on the potential position detection of same frequency noise, to repair most of the interpolation method is used to deal with noise in the radar image. Finally, the marine radar image is gotten after de-noising. Through the comparative analysis of the signal to noise ratio, it is proved that this method can get better de-noising effect.

In this article, we describe a hardware design scheme of the iris recognition system, which based on the infrared light, and taking the floating point DSP chip TMS320C6713 as the core. It described in detail the whole system in a modular way consisting of peripheral hardware structure, function, operation and other design elements. According to the system requirements, we select the appropriate chips and peripheral interface to carry on the design. At the same time, based on the hardware design, in order to ensure the accuracy of the recognition result of the system, we also need to conduct the thorough research to the image preprocessing algorithm. Through the test confirmation, this system has very high stability and reliability. The improved iris localization algorithm is simple and accurate, so it is easy to follow up on the iris image recognition operation.