Advanced Materials Research Vols. 718-720

Abstract: The optical sparse aperture imaging system consists of several small apertures for high resolution imaging. The incoherent light from each small aperture will form an image together strictly at the same focal plane, while the phase error will destroy such co-phase condition. The phase error is caused by deployment of small aperture and should be diminished. We applied digital holography technology to detect the wavefront of this system. The theoretical analysis and experiment are presented to demonstrate successful reconstruction of phase error.

Abstract: The error of the steel tape itself is an important factor to affect the measured length. According to the identification system of the improved identification procedures of steel tape, the industrial cameras are adopted to take photos for the steel tape and the standard steel tape which will be measured. At the same time, the LabVIEW image processing software is employed to process the photographs. Through comparing the errors of each point in the steel tape calculated by the image recognition, the identification results are finally obtained. The experimental results show that the proposed method is effective.

Abstract: Aiming at BP algorithm convergence slow and be prone to plunge a partial basis, an improved BP algorithm------ACBP Algorithm is proposed in this paper, it has better diversity and global search capacity. The ability of optimization for the algorithm is tested through numerical computation, the experimental demonstrates that the improved BP algorithm has better diversity and global search capacity than genetic algorithm, BP algorithm, ant colony algorithm and simulated anneal algorithm.

Abstract: In this paper, according to the characteristics and influence factors of the site of the public transport station problem, a mathematical model of the urban public transport station problem was established. Cloud computing and Quantum Algorithm was used to solve the model, with Hezuo city of Gansu Province as example, the algorithm was experimented and the experimental results show that the algorithm can acquire the optimal solution that is accord with the practice, moreover, the algorithm has much more practical.

Abstract: Medical image processing includes many basic components such as medical image filtering, medical image segmentation and medical image registration, whose advanced algorithms can be found in ITK platform. But the ITK is difficult for the beginners. Only simple function is used to call dozens of image processing algorithms by MATITK . Therefore by using MATITK , the students can master these advanced algorithms and the improved implementation results can be obtained.

Abstract: In order to improve search engine retrieval quality, using the vector space model is proposed based on the user's interest page pre-classifying and content related PageRank algorithm, the two aspects of the weights to influence of web pages with the PR value. Through the simulation experiment after improved algorithm experimental result, compared with the original algorithm, the improved algorithm precision better than the original algorithm.

Abstract: This paper discusses the issue of color interpolation on vertical stripe patterned color filter array (CFA), which is a process known as demosaicking. The objective and subjective performance are studied, and the results are displayed in the simulation result section. It was found to give superior performance and the satisfactory quality.

Abstract: Almost all digital cameras adopt a color filter array to acquire images and requesting a demosaicking process of the sub-sampled color components to have the full color image. Thus, it is necessary to restore the CFA image correctly. Otherwise, perceptible color errors are presented. This paper proposes a color interpolation algorithm based on filter. The CFA we used is modified Bayer CFA. Simulation results show that the proposed method is effective and yield high performance in CPSNR and S-CIELAB.

Abstract: This paper firstly analyzes the principle of face recognition algorithm, studies feature selection and distance criterion problem, puts forward the defects of PCA face recognition algorithm and LDA face recognition algorithm. According to the deficiencies and shortcomings of PCA face recognition algorithm and LDA face recognition algorithm, this paper proposes a solution -- PCA+LDA. The method uses the PCA method to reduce the dimensionality of feature space, it uses Fisher linear discriminant analysis method to classification, the realization of face recognition. Experiments show that, this method can not only improve the feature extraction speed, but also the recognition rate is better than single PCA method and LDA method.

Abstract: The use of Lamb waves for structural health monitoring (SHM) has complicated by its multi-mode character and dispersion effect, which impacts the damage positioning and high-resolution imaging. The group velocity dispersion curves of Lamb waves can be employed to warp the frequency axis, and then to establish warped frequency transform (WFT) to process Lamb waves. In this paper, received signals are directly compensated with warped frequency transform to suppress dispersion, and a new imaging method is proposed based on warped frequency transform. The propagation of Lamb waves in damaged aluminum plate is simulated by finite element software ABAQUS, results show that warped frequency transform can effectively compensate dispersive wave-packets, and high-resolution damage imaging can be obtained by the proposed method.