In order to solve the problems of having nonlinear observation equations and being susceptible to initial value of filtering in bearings-only target tracking, a range-parameterized hybrid coordinates Square Root Cubature Kalman Filter (SRCKF) algorithm was proposed. Firstly,it applied the SRCKF to hybrid coordinates,obtained better tracking effect than the SRCKF under Cartesian coordinates. And then it combined the range parameterization strategy with the SRCKF under hybrid coordinates, and eliminated the impact of unobservable range. The simulation results show that the proposed algorithm can significantly improve the accuracy and robustness although the computational complexity increases slightly.
To reduce the effect caused by Wireless Sensor Network (WSN) node signal power attenuation and node interference on transmission efficiency, an interference-aware routing based on random signal power fading model was proposed for WSN. First, according to probability theory, two probabilistic interference models for successfully transmitting data under different distribution of interfering nodes were put forward; interference, node routing convergence and residual energy issues were used as a measure to establish a interference-aware route. Then, interference, route convergence and residual energy were regarded as assessment weights to determine the best next-hop node. NS2 simulation data shows that compared with interference-aware routing algorithms based on differentiated services and coding, the proposed algorithm has better performance in packet delivery success rate, energy consumption and average delay time.
The current method of image classification which uses the Speed Up Robust Feature (SURF) is low in efficiency and accuracy. To overcome these shortages, this paper proposed an approach for image classification which uses the statistical features of the SURF set. This approach took all dimensions and scale information of the SURF as independent random variables, and split the data with the sign of Laplace response. Firstly, the SURF vector set of the image was got. Then the feature vector was constructed with the first absolute order central moments and weighted first absolute order central moments of each dimision. Finally, the Support Vector Machine (SVM) accomplished the image classification process with this vector. The experimental results show that the precision of this approach is better than that of the methods of SURF histogram and 3-channel-Gabor texture features by increases of 17.6% and 5.4% respectively. By combining this approach with the HSV histogram, a high-level feature fusion method was got, and good classification performance was obtained. Compared with the fused method of the SURF histogram and HSV histogram, the fused method of 3-channel-Gabor texture features and HSV histogram, and the multiple-instance-learning method based on the model of Bag of Visual Word (BoVW), the fused method of this approach and HSV histogram has better precision with the increases of 5.2%, 6.8% and 3.2% respectively.
Considering the problem that the role of the user cannot be changed dynamically over time in access control model of cloud computing, a new access control model was proposed based on trust of users' behaviors for cloud computing. The trust level was determined according to the trust value synthesized from direct trust and recommendation trust, the roles were activated and granted permission to access resources, then services provided the requested resources, so as to achieve the purposes of access control. Besides, the basic elements and implementation process were proposed. The experimental results demonstrate that the proposed model can improve the objectivity of the trust evaluation of users' behaviors, and it can resist all illegal users access to cloud computing and enhance reliability and security of the data in cloud computing.
A skew angle detection approach using Hough transform was proposed for OMR images. The proposed method doesn’t need to identify exact position of locating marks and can bear high noise. In order to avoid heavy computing of Hough transform, a low-resolution image was created by sampling OMR image. Also, a fast iteration algorithm based on run-length center for written marks segmentation was presented. Experiment results show that the algorithm can achieve skew correction and segmentation of OMR image efficiently and accurately.