The application of extended Kalman filter algorithm to ultrasonic positioning systems has difficulty in meeting the requirements of precision positioning because the algorithm produces a new calculation error when the...
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The application of extended Kalman filter algorithm to ultrasonic positioning systems has difficulty in meeting the requirements of precision positioning because the algorithm produces a new calculation error when the system is linearized. Modal optimization of the extended Kalman filter algorithm is thus investigated. The received ultrasonic signal is first decomposed by empirical mode decomposition, the intrinsic mode functions that best represent the original signal are then selected to restructure the waveform, and the transition time is finally corrected. Meanwhile, the ultrasonic wave velocity can be corrected. Traditional ultrasonic positioning can also be improved by combining with a radio-frequency module. It is experimentally shown that the proposed method limits positioning error to within ±5 cm and within ±1 cm after multiple recursions.
Accompanying increasing competition among the communication industry, maintaining and improving the stability and loyalty of customers has become the key determinant of profitability. In order to prevent the loss of c...
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Accompanying increasing competition among the communication industry, maintaining and improving the stability and loyalty of customers has become the key determinant of profitability. In order to prevent the loss of customers, we need to identify the stable users by data mining model. Through the evaluation of three models, Random Forest model performs with better robustness. This model can describe and predict most of the stable users in a shorter period of time. Consequently, the result will provide operators with the advantage of adopting reasonable marketing tactics timely.
Finding correspondences between two related feature point sets is a basic task in computer vision and pattern recognition. In this paper, we present a novel method for point pattern matching via spectral graph analysi...
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We propose new techniques for 2-D shape/contour completion, which is one of the important research topics related to shape analysis and computer vision, e.g. the detection of incomplete objects due to occlusion and no...
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We propose new techniques for 2-D shape/contour completion, which is one of the important research topics related to shape analysis and computer vision, e.g. the detection of incomplete objects due to occlusion and noises. The purpose of shape completion is to find the optimal curve segments that fill the missing contour parts, so as to acquire the best estimation of the original complete object shapes. Unlike the previous work using local smoothness or minimum curvature priors, we solve the problem under a Bayesian formulation taking advantage of global shape prior knowledge. With the priors, our methods are expert in recovering significant shape structures and dealing with large occlusion cases. There are two different priors adopted in this paper: (i) A generic prior model that prefers minimal global shape transformation (including non-rigid deformation and affine transformation with respect to a reference object shape) of the recovered complete shape; and (ii) a class-specific shape prior model learned from training examples of an object category, which prefers the reconstructed shape to follow the learned shape variation models of the category. Efficient contour completion algorithms are suggested corresponding to the two types of priors. Our experimental results demonstrate the advantage of the proposed shape completion approaches compared to the existing techniques, especially for objects with complex structure under severe occlusion.
Cloud computing has brought new opportunities for the development of traditional industries, but also appeared some new security risks. This paper analyzes the main data security problems in cloud computing field, and...
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Cloud computing has brought new opportunities for the development of traditional industries, but also appeared some new security risks. This paper analyzes the main data security problems in cloud computing field, and on this basis, to solve these security problems, puts forward the corresponding control strategy of data security.
This paper is considered with the H ∞ observer design problem for a class of nonlinear systems with the one-sided Lipschitz condition. The systems under consideration include the well-studied Lipschitz system as a sp...
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This paper is considered with the H ∞ observer design problem for a class of nonlinear systems with the one-sided Lipschitz condition. The systems under consideration include the well-studied Lipschitz system as a special case and possess inherent advantages with respect to conservativeness. For such systems in the presence of noises, we develop a Linear Matrix Inequality (LMI) based approach to design a nonlinear H ∞ observer by carefully dealing with the one-sided Lipschitz condition together with the quadratic inner-bounded condition. The resulting nonlinear H ∞ observer guarantees asymptotic stability of the estimation error dynamics with a prescribed H ∞ performance. Moreover, for the design purpose, the existence condition of the proposed nonlinear H ∞ observer is formulated in terms of LMIs by using a matrix generalized inverse technique. Finally, a simulation example is given to illustrate the effectiveness of the proposed design.
This paper proposes two hybrid prediction models using for predicting the displacement of landslide, Genetic Algorithm-Radial Basis Function Neural Network (GA-RBFN) and Genetic Algorithm- Back Propagation Neural Netw...
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This paper proposes two hybrid prediction models using for predicting the displacement of landslide, Genetic Algorithm-Radial Basis Function Neural Network (GA-RBFN) and Genetic Algorithm- Back Propagation Neural Network (GA-BPNN). A case study of Yuhuangge landslide in the Three Gorges reservoir in China is used to illustrate the capability and merit of our schemes. In addition, the result shows that GP-BPNN get better accuracy than GA-RBFN in the same measurements.
In this paper, a novel classification algorithm based on the ensemble learning and feature selection is proposed for predicting the specific microporous aluminophosphate ring structure. The proposed method can select ...
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In this paper, a novel classification algorithm based on the ensemble learning and feature selection is proposed for predicting the specific microporous aluminophosphate ring structure. The proposed method can select the most significant synthetic factors for the generation of (6, 12)-ring-containing structure. First, the clustering method is employed for making each training subset contains all the structural characteristics of samples. Then, the method takes full account of the discrimination and class information of each feature by calculating the scores. Specially, the scores are fused for getting a weight for each feature. Finally, we select the significant features according to the weights. The result of feature selection will help to predict the (6, 12)-ring-containing AlPO structure well. Moreover, we compare our method with several classical feature selection methods and classification method by theoretical analysis and extensive experiments. Experimental results show that our method can achieve higher predictive accuracy with less synthetic factors.
The IEEE 802.15.4 standard is widely used in wireless sensor networks (WSNs). In this paper, we propose a priority-based IEEE 802.15.4 carrier sense multiple access with collision avoidance (CSMA/CA) mechanism for...
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The IEEE 802.15.4 standard is widely used in wireless sensor networks (WSNs). In this paper, we propose a priority-based IEEE 802.15.4 carrier sense multiple access with collision avoidance (CSMA/CA) mechanism for WSNs. Considering traffic load and traffic type of sensor nodes, we classify sensor nodes into three types. In our mechanism, different contention parameters are set for nodes with different priority levels, in order that nodes with high priority achieve high probability to access the channel. By modeling the proposed mechanism using a Markov chain, we analyze and compute the successful transmission probability, throughput and energy consumption for nodes with different priority levels. Finally, our numerical results demonstrate that our mechanism performs well for WSNs.
Software testing is one of the most important techniques used to assure the quality of software service. An intricate issue in software testing is the determination of test orders for the integration test of classes, ...
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Software testing is one of the most important techniques used to assure the quality of software service. An intricate issue in software testing is the determination of test orders for the integration test of classes, known as the class integration and test order (CITO) problem. The determination of such order has an influence on the cost of created stubs for classes, which is an error-prone and costly process. To minimize the cost of stubbing, this paper describes a coupling measure technique to estimate the complexity of each test stub, and presents a graph-based heuristic algorithm of removing node with the highest weights to break cycles for minimizing overall complexity of stubbing. Also, an adjacency matrix and depth-first search for finding all the paths is presented. Simulation experimental results show that the overall test stub complexity decreased which greatly improves test efficiency and reduces the test cost to some extent compared with others.
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