Applied Mechanics and Materials Vols. 644-650

Abstract: For the problem of huge computation and requiring high computing resource in point cloud registration, according to the theory of parallel computing, the algorithm of point cloud registration base on MapReduce is designed. Through building a Hadoop cluster consisted by average PCs, four examples have been tested. The experiment results show that point cloud registration algorithm based on MapReduce can register point cloud data with high accuracy.

Abstract: Nonlocal differential operators have been extensively applied to variational models for image restoration due to its texture-preserving capability. In this paper, we propose a nonlocal TV (total variation)-L1 model for texture image inpainting, which, technically, combines nonlocal operators for regularization term and L1 norm for data term. The former is used to regularize texture and the latter to preserve contrast of images. In addition, we develop augmented Lagrangian algorithm for proposed model by introducing nonlocal auxiliary variable and Lagrangian multiplier. Finally, extensive experiments on synthetic and real texture images are presented to validate the effectiveness and efficiency of our proposed model and algorithm.

Abstract: In order to reduce banding and blurry edges produced by the conventional multilevel error diffusion algorithm in the digital halftone process, an improved multilevel error diffusion algorithm using neighborhood growing is proposed. According to human visual properties, the algorithm uses banding edge neighborhood alternately grow toward the center to revise halftone image. Experimental results show that the halftone image obtained by the improved algorithm eliminates banding and a better visual effect is achieved with the enhanced edges.

Abstract: Put forward an improved QIM watermark embedding algorithm. The carrier image is transformed into YCbCr space, lifting wavelet transform the three components, then using the QIM quantization method embeds watermark into high frequency coefficients of Cb and Cr component, and Y component of low frequency coefficients. The experimental results show that embedded watermark which using improved algorithm has good invisibility. Anti attack test results show that after using common attack method attack the image embedded watermark, it can still extract the watermark completely. The anti-attack performance of improved QIM algorithm is much better than texture watermarking algorithm based on DCT.

Abstract: The article introduces three-dimensional panoramic technology, and take Fang Zhimin martyr’s cemeter for instance, meanwhile, the process of using panoramic technology to create three-dimensional red tourist sites is described here in detail. It is thought that three-dimensional panoramic technology makes great sense in the protection of red cultural heritage.

Abstract: Denoising processing technology for remote classroom image transmission is studied. In the traditional method of image denoising, the image after denoisinghave obvious spots, communication is not ideal, noise variance estimation is required in practical applications. This paper presents a MCMC image denoising algorithm based on multi-core, throughremote image transmission fusion method toachieve fast denoising process for remote classroom image transmission. Experimental results show that the algorithm improves the operational efficiency, reduces speckle noise, so that remote image is clearer, and denoising effect is very satisfactory.

Abstract: Feature extraction is an important subject of image analysis, pattern recognition, computer vision, etc. It is the fundamental to solve many different image problems. As the local feature has the characteristic of invariability even after image translation and rotation, changing of zoom, illumination or viewpoint, it has been widely applied to image registration, image mosaic, object identification, target tracking, digital watermark and image retrieval. Extracting stable feature of images has attracted lots of interest. In this paper, we provide the definition of local feature and steps of extracting local feature. The difficulties and trend of this technology are also briefly discussed.

Abstract: The infrastructures of power grid can be easily damaged by fire disasters. Monitoring the spatial variations in the vegetation fraction is significant to predicate the probability of a fire disaster. While each vegetation indices (VI) computing method tends to suit some problem better than others, and typically have different parameters and configurations to be adjusted before achieving optimal performance on a dataset, we focus on conjunction with many types of traditional VIs' computing methods to improve their performance. Experimental results show that the accuracy of vegetation fraction estimation based on our method is higher than by using any single vegetation indices.

Abstract: Beam forming technology is an important content in the study of underwater target positioning, can directly use beam forming technology to identify the target direction, but can be by beam forming of target signal enhancement, and then to deal with the enhanced signal. No matter how to apply, beam forming technique can be regarded as a weighted sum of signal delay processing, its purpose is to form a beam and the scan to a specific direction. Based on uniform linear array as the example, this paper first of all, the simulation analysis of conventional beam forming technology direction scanning accuracy and array element spacing, number of array element, the relationship between the signal frequency; Then by analyzing grid scanning beam spatial distribution of power spectrum and the quantitative relationship between linear arrays, studying a selection method is suitable for the engineering application of fast beam domain, high precision and fast direction to estimate.

Abstract: The objective of this study was to evaluate the use of high pressure processing (HPP) as a preservation method of meat products. Vacuum-packaged fish patties were subjected to HPP (300 MPa for 30 min 15°C or 500 Mpa for 10 min at 15°C). Untreated samples represented the control group. The three groups were stored at 4°C for 0–5 weeks. Color parameters, pH, thiobarbituric (TBARS), bacterial growth, and Oxidation-Reduction Potential (ORP) were determined. The results revealed that the 500-MPa treatment inhibited bacterial growth and extended the shelf-life of fish patties to four weeks with insignificant effects on the physicochemical attributes.