Adaptive template filter method for image processing based on immune genetic algorithm

To preserve the original signal as much as possible and filter random noises as many as possible in image processing,a threshold optimization-based adaptive template filtering algorithm was proposed.Unlike conventional filters whose template shapes and coefficients were fixed,multi-templates were defined and the right template for each pixel could be matched adaptively based on local image characteristics in the proposed method.The superiority of this method was verified by former results concerning the matching experiment of actual image with the comparison of conventional filtering methods.The adaptive search ability of immune genetic algorithm with the elitist selection and elitist crossover(IGAE) was used to optimize threshold t of the transformation function,and then combined with wavelet transformation to estimate noise variance.Multi-experiments were performed to test the validity of IGAE.The results show that the filtered result of t obtained by IGAE is superior to that of t obtained by other methods,IGAE has a faster convergence speed and a higher computational efficiency compared with the canonical genetic algorithm with the elitism and the immune algorithm with the information entropy and elitism by multi-experiments.

Fingerprints Matching Based on the Integrated Template

Traditional fingerprints matching approaches are based on the minutiae and the texture characteristics. It is difficult for today's techniques to deal with the images captured by the solid-state fingerprint sensors because the sampling area of these sensors is very small and only portion of the fingerprint can be obtained. In this paper, a novel integrated template has been built using several images and combining the minutiae with the texture characteristics at the same time. By using a kind of Gabor filters (eight directions) on the region around the reliable minutiae, local texture of each minutia termed as minutiacode is extracted. Further, a real-time matching algorithm using the integrated template is presented. The output is determined by the weight factor of the compound matching. Finally, experimental results show that this system performs well in reducing false reject rate (FRR).

Study on Azimuth Variation of Airgun Signal Propagation

Based on the data recorded by the observation network during the intensive excitation period from November to December 2015 at Binchuan Earthquake Signal Transmitting Seismic Station(BESTSS)in Yunnan Province,the noise in waveform recording is removed by S-transform template filtering method,and the azimuth of airgun signal propagation is calculated and analyzed from the horizontal waveform recordings.The results show that:①the azimuth angle of airgun signal after propagation is sensitive to stress change,and can clearly reflect the diurnal variation of tidal stress,which can be used to monitor the change of stress state in crustal medium;②the azimuth angle of airgun signal in some stations has changed abruptly after propagation on December 4,which may be related to the change of airgun source;③five-shot superposition or fivepoint smoothing of azimuth angle of single shot are carried out for airgun signals in stations far away from epicenter,and results show that azimuth angle from superposition or smoothing is more stable and has clear diurnal variation characteristics after propagation.

Filter paper-templated preparation of ZnO thin films and examination of their gas-sensing properties

ZnO thin films prepared by using quantitative filter paper as a template and Zn（CH3CO2）2.2H2O ethanol precursor solution were characterized by scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The effects of sample calcination temperature, precursor concentration and filter paper types were studied, and the growth process was investigated by infra-red （IR） spectroscopy and thermogravimettic analysis/differential thermal analysis （TGA/DTA）. The results show that samples soaked in a 1.5 mol/L Zn（CH3 CO2）2.2H2O ethanol solution and calcined at 600 ℃ yield ZnO films of uniform particle size, approximately 30, 40 and 50 nm. for fast-, medium- and slow-speed filter papers, respectively. The formaldehyde gas sensing properties of the ZnO nanoparticles were tested, showing that the material prepared from fast-speed filter paper has a higher response to 120-205 ppm formaldehyde at 400 ℃ than that prepared from medium- or slow-sneed paper, which depends on the narticle size.