Applied Mechanics and Materials Vols. 157-158

Abstract: Due to the nonlinear characteristics of modern power systems, strong interaction between system angle stability and voltage stability will present. However, because of extreme complexity, these two kinds of stability are often investigated separately and the interactions between them are normally neglected in traditional studies. In this paper, a new method based on the theory of normal forms of vector fields and singular perturbation theory is introduced to deal with the power system structure preserving model for system stability modes interaction analysis. The relationship between angle and voltage stability is discovered. The method is validated with a sample power system.

Abstract: The paper analyzes the characteristics and the situation of the control of multivariable coupling system, combining improved PID neural networks with PSO algorithm, and finally designs a suitable controller model. To achieve a controller model, an initial structure of PID neural networks is established in the first place. Then weights in the network is initialized by PSO algorithm and optimized by improved gradient descent algorithm. A simulation, MIMO coupling system, prove this controller has such characteristics with short time and high precision. The research of the paper provides a new idea and approach for control of complex coupling system.

Abstract: The existing transportation service system in public travel route can not satisfy the people's actual travel need because of various technologies reasons. In our study, we set the tourist attractions as a vertex, and simplified the traditional algorithm for complex network computing. Aim to improve the disadvantage of tradition Dijkstra algorithm, an improve algorithm was proposed to improve the path search efficiency. Then the improved Dijkstra algorithm was applied to tourism path search. The experimental results have illustrated that the improved Dijkstra algorithm can accomplish a better result and improve path search efficiency.

Abstract: This paper studied the key factors affecting the amplitude of a composite ultrasonic wiredrawing vibration system, for designing a powerful ultrasonic vibration system. The finite element analysis (FEA) was performed. The results showed that the variable cross-section shapes of horns and the angles between the connection of both ends of the cross-section and the center line had great effects on the amplitude of an ultrasonic vibration system. In order to valid the theoretical result, the experiments were carried out on a composite ultrasonic vibration system. The experimental result demonstrated that the conical variable cross-section rods used in an ultrasonic vibration system produced large amplitude.

Abstract: Machined residual stress is an important index in machining quality, and pre-stress cutting is a process which can increase the residual compressive stress on machined surfaces. This paper investigated the effect of machining parameters and pre-stress on residual stress of 40Cr steel by orthogonal experiment. The experiment results also showed that pre-stress could increase the residual compressive stress effectively, and it had obvious significance for residual stress than those significances of machining parameters; ap had more obvious affect on the residual stress than vc and f have, and residual compressive stress decreased with the increase of ap, vc and f. A prediction formula for residual stress of pre-stress hard turning was obtained from the experiment results and it was verified reliable by other experiment.

Abstract: This paper designs a cooperative strategy for unmanned aerial vehicles (UAVs) searching for moving and possibly evading targets. By arranging UAVs into an efficient flight configuration, they optimize their integrated sensing capability, and are thus capable of searching smart targets than uncooperative UAVs. If a UAV is shot down, the team adapts to continue the mission with surviving assets. Simulation results show that our proposed strategy can achieve superior search performance.

Abstract: The relationship between modern furniture color image and eye tracking has been of interest to academics and practitioners for many years. We propose and develop a new view and method exploring these connections, utilizing data from a survey of 31 testees’ eye tracking observed value. Using Tobii X120 eye tracker to analyze eye movement to furniture samples in different hue and tones colors, we highlight the relative importance of the effect of furniture color on human vision system and show that the connections between furniture color features with color image.

Abstract: Data association is one of the most important issues in multi-target tracking for radar network. In order to meet the high real-time requirement of the multi-target tracking system in the future, a data association method based on time restraint is presented. Firstly, the modified association probability matrix between the observations and tracks is calculated, and the optimal association model is established. Then, the time restraint based auction algorithm is proposed to solve the association issue. The design and flow of this algorithm is offered, and the simulation of the method is designed. Simulation results demonstrate that the proposed method has an ideal association performance in the restrained time.

Abstract: Considering the rheological characteristics of soil, think the fractional maxwell with viscoelastic model can be described, the fractional maxwell model into integral form of saturated soft soil layer, the one dimensional compression, through the Laplace transform problems get instantaneous loading and single stage, the analytical solution of the loading conditions.

Abstract: Localization problem has great significance in the applications of underwater sensor networks (UWSN), such as real-time monitoring, target tracking and navigation. This paper analized a series of challenges in underwater localization problem, introduced exsiting localization algorithms and discussed their advantages and disadvantages, and then the development trend of localization problem is discussed. Finally, we give some suggestions in the design of localization algoprithms.