Applied Mechanics and Materials Vols. 130-134

Abstract: In order to reveal the complex turbulent combustion processes in the afterburning chamber of Solid Ducked Rocket (SDR), Based on the fundamental equations of hydrokinetics and elementary principles of radical reaction kinetics, using multi-component chemical reaction equation of containing Mg and Al components, the numerical simulation of chemical non-equilibrium flow in the afterburning chamber of SDR is processed and effects of the air inlet angle on the afterburning chamber is studied by using Fluent software. The results show that pressure distribution is more balanced, temperature distribution is very uneven and flow is extremely complicated in the afterburning chamber. Combustion efficiency can be increased by improving the air inlet angle.

Abstract: The core technology of electronic ois is the motion estimation techniques, such as, BPM, RPM, FTA ,PA, BM and so on^[1]. Based on the excellent tracking performance of Mean Shift algorithm in complicated scene, this paper proposed a target tracking method based on corner, and then work on motion compensation and motion estimation.

Abstract: On-Line Analytical Processing (OLAP) tools are frequently used in business, science and health to extract useful knowledge from massive databases. An important and hard optimization problem in OLAP data warehouses is the view selection problem, consisting of selecting a set of aggregate views of the data for speeding up future query processing. In this paper we present a new approach, named HGEDA, which is a new hybrid algorithm based on genetic and estimation of distribution algorithms. The original objective is to get benefits from both approaches. Experimental results show that the HGEDA are competitive with the genetic algorithm on a variety of problem instances, often finding approximate optimal solutions in a reasonable amount of time.

Abstract: Based on accurately considering the axial extension, geometrically nonlinear governing equations for a two-layer beam subjected to thermal load were formulated. By using a shooting method, the strongly nonlinear ordinary differential equations with two-point boundary conditions were solved and numerical solution for thermal post-buckling and bending deformation of a two-layer beam with pinned-pinned ends and subjected to transversely non-uniform temperature rising were obtained. As an example, equilibrium paths and configuration for a beam laminated by brass and steel are presented and characteristic curves of the nonlinear deformation changing with the thermal load were plotted. Effects of the geometric and material parameters on the deformation of the beam were discussed and analyzed in detail. The theoretical analysis and numerical results show that the bending deformation and the stretching-bending coupling terms of beam subjected to uniform or non-uniform temperature rising can be produced because of the non-homogenous distribution of the material properties. The bending deformation resulted from transversely temperature rise is primary deformation when values of average temperature rise parameter is under critical temperature, however, the curves become the thermal post-buckling equilibrium paths with the increment of average temperature rise when values of average temperature rise parameter exceed critical temperature.

Abstract: In R9 version of LTE system, the double multi-user beamforming is proposed. To suppress inter-user interference of multi-user multiple input multiple output (MU-MIMO) system, a new algorithm is presented in this paper: on condition that current user eliminates the interference to other users, it designs its own transmit beamforming vector; if all users take such measures, the interference that each user suffers from others will be reduced to a minimum, which improves the performance of the system. Simulation shows that, as the number of user increases, the algorithm used in this paper can reduce the bit error rate (BER) of the system more obviously than the traditional signal-to-leakage-and-noise ratio (SLNR) algorithm.

Abstract: Facial expression analysis is important in Human-Computer Interaction. How to improve the accuracy and objectivity of analysis should be concerned about. In this paper, a novel approach to context-aware based facial expression nets model is proposed. According to interactive environment’s characteristics and the relationship between context factors and facial expression features, CFEN model is constructed and applied to compute and analyze participant’s realistic facial expression in the context environment. It is possible to achieve facial expression’s knowledge representation and reasoning analysis. Experiment is designed and conducted to verify the theoretical model and approach proposed in this paper.

Abstract: In recent years, the security of software becomes one significant feature of software. This paper improves trustworthy software engineering through a knowledge based expert system. We propose the knowledge collection and organization method, and threats analyzing algorithm in detail which are the kernel of the expert system. The software threat information is divided into threat state and exploit, and stored in the knowledge database together with the state production and exploit production representing the relationships between threat state and exploit. The threat analysis calculates the threat degree quantitatively of an application based on this knowledge in a formal way and give security advice to mitigate threats. Our method can reduce the work of an experienced security expert which is time consuming and economic costly, therefore popularizes the trustworthy software engineering.

Abstract: This paper presents a least square influential coefficient based on particle swarm optimization, putting balance weight as optimizing object, which can make residual vibration meet the expected demand. Experimental result shows that this method has high performance optimizing effect, and high percent of removed unbalance amount one correction, which is over 95%. So this method has very high practical value.

Abstract: By analyzing multi-parameter rotor power coefficient model used in wind generator system, fitting surface function and its nonlinear equations set are established. The nonlinear equations set is converted to the linear equations set by Newton method, and then the linear equations ser is being solved. This paper designs the method of collecting sample data to fit rotor power coefficient of wind turbine. Theoretical analysis proves that this method is effective. The example results show that the rotor power coefficient fitted by the method has high accuracy and better value of engineering applications, and is also suitable for the models of wind generator systems with different parameter perturbation situation.

Abstract: A robust controller of wind turbine pitch angle is designed by using the quantitative feedback theory based on the analysis of wind power system model in this paper. The controller design methodology is to select the system parameters quantitatively at different wind speed disturbances in order to optimize the response time and the output stability. Theoretical analysis and simulation results demonstrate that the controller can control the speed stability of wind power system with strong robustness to uncertain disturbances of the system parameters when the wind speed fluctuates randomly.