Adaptive cross approximation (ACA) algorithm as a kind of common matrix compression method is often used to analyze the electromagnetic radiation and scattering problems. In the region of far field, the impedance matr...
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ISBN:
(纸本)9781467317993
Adaptive cross approximation (ACA) algorithm as a kind of common matrix compression method is often used to analyze the electromagnetic radiation and scattering problems. In the region of far field, the impedance matrix is compressed by ACA method, and the extracted impedance matrix is accelerated filling by equivalent dipole-moment method (EDM). In the area of near field, the method of moments or the equivalent dipole-moment method is applied for filling the impedance matrix. The iterative near field preconditioning technique is used to solve matrix equation, so that fast calculation of radar cross section (RCS) can be achieved. Numerical results show that the computational efficiency is improved significantly via applying the presented method in this paper without sacrificing much accuracy.
In this paper, we present a novel idea to solve maximum flow problem in the directed networks. Given a directed flow network which we call original network here, we propose a method of Contracting Neighbor-node-set Ap...
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In this paper,we propose an iterative two-grid method for the edge finite element discretizations(a saddle-point system)of Perfectly Matched Layer(PML)equations to the Maxwell scattering problem in two ***,we use a fi...
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In this paper,we propose an iterative two-grid method for the edge finite element discretizations(a saddle-point system)of Perfectly Matched Layer(PML)equations to the Maxwell scattering problem in two ***,we use a fine space to solve a discrete saddle-point system of H(grad)variational problems,denoted by auxiliary system ***,we use a coarse space to solve the original saddle-point ***,we use a fine space again to solve a discrete H(curl)-elliptic variational problems,denoted by auxiliary system ***,we develop a regularization diagonal block preconditioner for auxiliary system 1 and use H-X preconditioner for auxiliary system *** we essentially transform the original problem in a fine space to a corresponding(but much smaller)problem on a coarse space,due to the fact that the above two preconditioners are efficient and *** with some existing iterative methods for solving saddle-point systems,such as PMinres,numerical experiments show the competitive performance of our iterative two-grid method.
The weighted circles layout problem belongs to the layout optimization problem with performance constraints. Due to its NP-hard property, it is difficult to solve in polynomial time. In this paper, a heuristic particl...
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Privacy-Preserving Computational Geometry (PPCG) is a special Secure Multi-party Computation, which is a hot research in information security. This paper presented a special PPCG problem of secure two-party computing ...
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In recent years, WSN (Wireless Sensor Network) technology has been developed rapidly, and been widely used in the fields of industry, agriculture, medicine and so on. To solve the low communication rate and short-dist...
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ISBN:
(纸本)9781467344999
In recent years, WSN (Wireless Sensor Network) technology has been developed rapidly, and been widely used in the fields of industry, agriculture, medicine and so on. To solve the low communication rate and short-distance data transmission in the current temperature and humidity monitoring system, this paper designs a temperature and humidity remote monitoring system based on WSN technology. In this system, microprocessor Atmega128L is adopted as the control core of network node, and wireless transceiver module nRF905 is used to realize wireless data transmission. The data of temperature and humidity is sampled by using digital temperature sensor DS18B20 and humidity sensor SHT75 in the system. The proposed network protocol in this paper not only can realize long-rang wireless data transmission, but also can realize self-organizing and manual networking. The results of practical test show that this system has the stable and reliable performance and the advantage of scalability.
Based on adaptive filtering and retinex method, this paper presents a novel algorithm for Enhancement of hand vein images. First of all, the principle of the near-infrared hand vein image acquisition is introduced. Se...
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Based on adaptive filtering and retinex method, this paper presents a novel algorithm for Enhancement of hand vein images. First of all, the principle of the near-infrared hand vein image acquisition is introduced. Secondly, the retinex method is used to normalize hand vein images, and the adaptive smoothing method is selected to estimate the illumination. Thirdly, Gray cosine transform is used to enhance the discrimination of the skin and the vein in hand vein images. Finally, a determination criterion of hand vein is established to remove the false vein blocks from the segmented hand vein images. We developed a hand vein recognition system in Microsoft VC6.0 and the experimental results demonstrate the high efficiency of the proposed algorithm in runtime and correct recognition rate.
In the theory of compressive sensing, the selection of the basis functions directly affects the sparse transformation, observation number and reconstruction accuracy. In this paper, we introduce the structure of three...
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A contour tree is a topological abstraction of a scalar field. Contour tree simplification (CTS) removes branches corresponding to noise, while making the size of the tree small enough for maintaining essential struct...
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Fuzzy soft set (FSs) is a novel mathematical tool, in order to describe and measure uncertain information of FSs perfectly, granularity analysis based on covering about FSs is originally discussed in this paper. First...
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