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Experiment teaching or research can't be carried out on schedule at some schools and research institutions due to the lack of sufficient experiment instruments or other reasons. Virtual experiment technology could resolve the problem effectively, and would play an increasingly prominent role in modern teaching. This project designed and accomplished a series of aerodynamics virtual experiment software...
In this paper, the almost periodicity and pseudo almost periodicity are generalized to n-dimensional space, and their properties are considered. Applying the properties we get, and the contraction fixed point theorem, we prove the existence and uniqueness of the pseudo almost periodic solutions to the nonlinear n-dimension heat equation.
From the viewpoints of information theory and system theory, an Information Optimizing Model is proposed based on following rules of language: efficiency, cooperation, distinction, evolution, and reliability. It proposes that language is an optimal encoding system to communicate in the most efficient way. Using this model, a hypothesis is made that when expressing the same meaning using a sentence,...
In this paper, kinematic analysis of the 5-PPaPaU parallel mechanism with parallelogram loops was presented. Based on the analysis on the DOF of the mechanism, the prismatic joints placed on the base were chose as actuators. The singularity configuration of the mechanism was researched. The successive transformation matrixes were derived, and then the inverse kinematic equations and direct kinematic...
An advanced threshold secret sharing scheme to identify cheaters is proposed in this paper by using authentication codes. The performance of the scheme is discussed. The results show that in the scheme the valid shareholders not only can identify the impersonation of an adversary, but also are able to detect cheating of some valid shareholders. In particular one honest shareholder is able to detect...
Combined with the one-dimensional isentropic flow theory, method of CFD is used to simulate the whole flow field of a certain convergent-divergent nozzle under the typical operation. The paper describes the gird generation, boundary conditions determination, flow field initialization as well as RNG k-e turbulence model application, and analyzes the nozzle aerodynamic characteristics. Studies have...
The phase field method is an effective method on solidification microstructure simulation. In this paper, the basic principles and the phase field model are introduced respectively. And then, the applications of phase-field simulation on solidification microstructure are summarized briefly. Finally, the problems to be faced and the future development trends are pointed out in this area.
A robust aspect ratio based agglomeration algorithm to generate coarse grids for unstructured grid and hybrid grids is proposed in this paper. The algorithm focuses on multigrid techniques for the numerical solution of Navier-Stokes equations, which conform to cell-centered finite volume scheme, combines isotropie vertex-based agglomeration and high-stretched cell-based directional agglomeration to...
In this paper we study on a tracing system for infrared target and propose an optimized algorithm to track and recognize the objects such as flying target. So we need to detect the moving targets from the background in image sequences, and keep track of them by the Kaiman filter algorithm and image processing. In the first stage, we segment the moving regions from the background area with GMM(Gaussian...
The problem of absolute value operators is converted to the problem of 2 × 2 operator matrices. Using the properties of the Hadamard product, we will study some inequalities involving A∗ B + B∗ A, |A + B| and |A|, |B| A result in this paper can extend F. zhang's in paper [3] absolute value of operator equation, then can obtain the more extensive version of the Bohr inequality.
Solving linear equations is key in many scientific research and engineering computing, in order to solve effectly large-scale linear matrix equalities, the traditional algorithm for solving linear equations is analysed and iterative methods is introduced to improve efficiency and reduced storage and algorithm simple. The methods suggested conjugate methods is an effective in storage and compution.
A new quasi-Newton multiuser constant modulus algorithm based on fractional lower-order statistics for the problem of blind source separation and equalization for multiple-input /multiple-output (MIMO) channels in heavy-tailed impulsive noise is introduced. This algorithm can improve the convergence performance than that of the fractional lower-order multiuser constant modulus algorithm (FLOS_MU_CMA)...
Multi-signature has become increasingly important in the field of the digital signatures. The enterprise document multi-signature transmission system design is studied. The enterprise document signature is divided into two parts: in order and without order. In this paper signature without order is discussed and the broadcasting multi-signature is proposed to solve the multi-signature in the enterprise...
Software development is a high-risk activities in the project development process. Any stage may be at risk. Risk occurred in the project is a series of events or the possibility of adverse results. To take active risk management approach can process more smoothly the project can get very high ability to track and control project, you can avoid, transfer risk, or mitigate the risk of adverse effects,...
Signcryption is a technology that combines digital signature and encryption in a logical manner. This paper proposes a certificateless signcryption scheme. The scheme not only realizes the property of the certificateless, but also solves the inherent problem of key escrow in identity based public key cryptography. The results of analysis show that the scheme has the properties of public verifiability,...
It's the requirement to research data replication strategies for improving the reliability and efficiency of complex network. We use noncooperative game theory to analyze the replica placement problem in the paper, and the model of replica placement in large-scale distributed network is proposed. Then we prove the existence of pure strategy Nash equilibrium in the model, and propose the replica placement...
Let A be an m × n complex matrix. The decomposition A = QH is termed a polar decomposition of A, where Q is an m × n polar factor and H is a positive semi-definite matrix. In this paper we improve some results corresponding to the H — factor.
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