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The sub-pixel subdivision algorithm of image processing and measurement is studied in this paper. On the basis of the principle of sub-pixel subdivision, and combined with the gradient direction of boundary points using Gaussian curve interpolation algorithm, the location of the boundary points has been located to sub-pixel level. Through the comparison of sub-pixel subdivision experiment conclusion...
Parallel FDTD algorithm for simulating anisotropic media with arbitrary permittivity and permeability is developed. It is found that for the anisotropic medium, the field components at one FDTD mesh node can be obtained by the data at the neighboring 28 mesh nodes. The communication rules of the data between these neighboring 28 nodes when locating in different adjacent sub-domains are discussed in...
Due to the increase of power load in the central area of big cities, the application of power cables are quickly increased. Compared with other laying methods, pipeline shows some significant advantages, and also some disadvantages such as the difficulty of obtaining its temperature distribution and setting its suitable ampacity. On the basis of FEM model of temperature field of 10kV underground pipe-laid...
A displacement back analysis, named as CACA-SVM, was proposed by combining the Support Vector Machines (SVM) and the Continuous Ant Colony Algorithm (CACA). The model used both the nonlinear characteristics of the Support Vector Machines to reduce numerical calculation and the global optimization performance of the Continuous Ant Colony Algorithm to avoid trapping in local optimum. The model was applied...
Although image robust hashing has drawn many attentions as a promising image authentication technique, the tamper detection and localization of robust hash algorithm has not been explored thoroughly. The most important difficulty is the conflict that the hash value is supposed to be robust to common content-preserving manipulations (CPM), such as lossy compression, but sensitive to malicious tamper...
In this paper, a QoS provisioning spectrum decision algorithm based on predictions is proposed in cognitive radio networks. By recording and analyzing the historical information, the algorithm can learn intelligently the rule of occupied spectrum by licensed users, and can predict the length of a spectrum hole, with the combination of the use's QoS request to provide a basis for spectrum decision...
Based on the Particle Swarm Optimization algorithm, the real parts of the 2-D homogeneous and the isotropic medium was reconstructed by the method of moment in the circle configuration, and the analysis was noise free and constrained. The result shows the reconstruction method was suitable in this circumstance. The study will provide the theoretical preparation, such as clinical diagnosis, remote...
Cognitive radio is a dynamic spectrum access technology as a solution to spectrum under-utilization problem in some licensed bands. Cognitive radio should sense the spectrum usage steadily to prevent interfering licensed users and spectrum occupancy information of licensed users can be used both for learning the usage and prediction of the future occupancy. In this paper, a two-state high-order Markov...
In order to improve the deficiency of existing Web service integration methods, this paper proposes an agent-based web service integration model and designs the organization structure and communicating pattern of the multi-agents system in this model. Moreover, a general QoS model is established to realize the predetermined objective under the constraint of the QoS of composite services. Finally,...
The existing Web services integration systems are facing three major problems: the structure of integration framework is inflexible and is difficult to adapt to the complex network circumstance; Web services lack autonomy, individuality and intelligence; Single mode of service integration is difficult to ensure the QoS of integration system. Around these problems, we propose an agent-based Web services...
With the Internet developing, there are many documents on the same topic which contains redundance. Multi-Document summarization is a technology of natural languages processing, which extract important information from multiple texts about the same topic according to the compression ratio. Sentence selection is an important part of Multi-document summarization .In this paper, we design a calculate...
Subblock Successive Transform (SST) algorithm is an effective method to reduce the PAPR of the MIMO-OFDM signals, and can fully utilize the degrees of freedom in space domain to overcome the shortage of Successive Suboptimal Cross-Antenna Rotation and Inversion (SS-CARI) algorithm. However, the degrees of freedom in frequency domain are not considered in SST algorithm. For this problem, an improved...
This paper described Phase-amplitude control methods, based on fix step-size (FSS-LMS) and variable step-size (VSS-LMS) in ALINE neural network control respectively, were compared and analyzed on the simulated hydro-pneumatic suspension control system. The test results indicated that phase-amplitude control method could improve the sine signal reappeared accuracy in limited range, efficiently realize...
Sectional views are widely used in engineering practice due to their clear and concise expression. However, large numbers of entities are missing in sectional views that makes it hard for computer to understand drawings. Feature identification is the key procedure for solids reconstruction from sectional views. Based on the analysis of the default drawing rules appearing in sectional views, a new...
Legendre moments have been widely used as feature descriptors in image analysis. This paper presents a new approach for the exact computation of Legendre moments of binary images. Using a Green's formula, the double integral is first transformed into a simple integration along the boundary which is represented by a polygon. We then propose an efficient method for computing the line moments. Comparison...
A novel image perceptual hashing algorithm is proposed on the intermediate hashing stage. It first uses an iterative geometric technique to extract significant geometry preserving feature points. Then, the fuzzy distance matching method is proposed based on the observation that the distances of feature points are invariant in the polar coordinate under arbitrary rotation. It is verified that the proposed...
Proposed the services composition algorithm based on QoS which combined local strategy and global strategy for constraints. The algorithm eliminates the services with low QoS firstly and then reduces the problem of services composition plan selection for global QoS guarantee to multi-dimension multi-choice 0-1 knapsack problem which is solved by the heuristic method for improving the efficiency of...
Proposed an automatic composite service template selection method based on ontology. In the method the Web services are described by OWL-S and domain ontology. The measure of association degree between services is reduced to the problem of finding perfect matching in service bipartite graph which is solved by the improved Kuhn-Munkres algorithm. Finally, we proposed the automatic composite service...
A lot of existing algorithms used for mining association rules identify frequent itemsets by the method of bottom-up combination of smaller frequent itemsets or top-down decomposing of larger infrequent itemsets, these methods result the large volumes of candidate itemsets. Actually as the supersets of infrequent items are infrequent itemsets, this paper presents a new efficient method, namely pruning-classification...
The paper presents a new method to design regional coverage satellite constellation, the non-dominated sorting genetic algorithm II (NSGA-II) based on Pareto optimal is improved and applied it to the optimization of regional coverage satellite constellation. The best solution, depending on the importance of different objects, is selected by a kind of multi attributes decision making method. Simulation...
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