Applied Mechanics and Materials Vols. 380-384

Abstract: Large touch screen systems (LTSS) have been widely used in scientific, industrial, educational and artistic domains. They are easy and natural for people to use. We present a novel touch screen interaction with finger pointing and operating. To track the high freedom of fingertips with quick changes and self-occlusion by using ordinary cameras is a complex and challenging task. We propose a series of computer vision (CV) algorithms to fix initial position, coordinates mapping, fingertip detection, fingertip tracking, fingertip pose recognition, and generate control instructions. Evaluation shows our system is simply implemented and has a great effect.

Abstract: An image fusion algorithm by combing Nonsubsampled Contourlet Transform and Pulse Coupled Neural Network is proposed in this paper. Two primitive matched images are decomposed in NSCT domain. The low frequency used the regional energy weighted fusion. The high frequency coefficients are input to the PCNN. Finally, the fused result is obtained through inverse NSCT. The novel algorithm will employ features and contain the most of the energy of image. The simulation results show that the results are much better than the experimental results, which the mutual information and Q^AB/F parameters are higher than the contrast method of fusion results.

Abstract: The major challenge in area stereo matching algorithms is to find appropriate window size and shape. Phase congruency is robust to noise and can reflects the gray changes. With these benefits, the paper first detects image and determines pixels characteristics according to phase congruency. Then, different window will be used to matching according to different feature pixels. After using cost function which combined with non-parametric measure and gray value, the final disparity map will be obtained. The result of experiment indicates that the algorithm can generates more accurate disparity map.

Abstract: The edge of image is one of the important features of the image, edge detection is an important means to extract image features. As the most popular high-performance processing technology, GPU parallel technology is on of the best choices for parallel Prewitt algorithm implementation. Since conventional Prewitt algorithm based upon CPU is computationally intensive, time-consuming, its application is very restricted. In order to improve the efficiency of Prewitt algorithm, CUDA-based parallel Prewitt algorithm and fast imaging algorithm are applied to get higher speedup. Finally, an effective method is proposed by turning the GPR field data into gray-scale image data, then implementation of GPR field data processing with the Prewitt algorithm based upon CUDA. Numerical results on GPR field data have shown that the algorithm is not only of high efficiency, but effective to improve target identification capability based upon GPR.

Abstract: The radio spectrum is limited, but in urban and rural areas some bands of radio spectrum are idle in most of the time. Some bands of radio spectrum are occupied occasionally. On the other hand, some bands are excessively used. This paper propsed an adaptive time division Duplex (ATDD) technology to effectively improve the transmission delay in the large range ,such as the rural network in 802.22 network.

Abstract: To study urban land cover information extracting method used one scene LANDSAT-TM remote sensing image of Chongqing city, China. Since NDVI calculation can enhance vegetation information, a calculation expression which is built according to water spectrum feather can enhance water information, and NDBI (Normalization Difference Building Index) calculation can enhance impervious surface information, the three calculations were used to get three thematic images, and after stacking them on to be one image, supervised classification used k-Nearest Neighbor algorithm based on Object-Oriented features of the image was used to get vegetation , water and impervious surface information. To value the final accuracy of the classification, 100 random sampling points were chosen and the high spatial resolution remote sensing image of Google Earth was taken to be the reference, the overall classification accuracy is 83.4%, and the Kappa statistic is 0.814.

Abstract: To expand the visual field of the 3D display screen, we propose a 3D visual image location controller based on the visual evoked potential (VEP). The controller evokes potential information by visual simulator. It constructs high quality data collection system by an EEG amplifier, then abstracts the characteristics of the EEG signal by signal processing algorithm and controls the movement of image on the 3D display screen by transforming them into controlling signal. This research can expand the visual field of the 3D display screen.

Abstract: With the development of society, much technology has been invented, many problems have been conquered. But it is still very hard for medical science. For example, physicians usually obtain the lesion information by means of medical imaging equipment and computer visualization techniques, to judge the symptoms, and develop appropriate treatment programs. However, it is hard for Magnetic Resonance Imaging (MRI) equipment to get high-quality image of the lesion, and then extract the pathological features of high quality. This paper will introduce a method to overcome this tough stuff. This paper attempts to adopt compressed sensing technology for image processing in the bone repair process. Lesion images are first acquired via MRI, then with the wavelet transform, to get the sparse matrix by the wavelet coefficient sparse representation. The method can obtain compressed images, and extract the corresponding pathological features without reducing the image quality.

Abstract: The accurate synchronization signal at the receiving end is obtained and chaos synchronization of two single ring laser is achieved through numerical simulation by master-slave method. It is founded that chaos synchronization of Erbium-doped fiber ring laser with master-slave can be realized and synchronization is unconcerned in initial system. These results will be useful to control and application of chaos in secret communication.

Abstract: To improve the accuracy of initial timing, an estimation method with the cooperation of distributed receive antennas is proposed in this paper. In the cooperation area, we consider two distributed receive antennas to receive the signal transmitted from the MS over the flat Rayleigh channels. The prior information of coverage region from each distributed receive antenna is firstly exploited to form a precondition of cooperation. Then we derive the threshold detection method based on the precondition. With the proposed method, the simulation results show that the probability of correct estimation for each distributed receive antenna is improved.