Applied Mechanics and Materials Vols. 130-134

Abstract: The singular value decomposition is employed to identify heat boundary conditions for 2-D anisotropic coating structures. The boundary element method is applied to analyzing the model. The nearly singular integrals in the boundary element method for thin body problems are dealt with by the analytical integral formulas. The ill-posed system is treated by the truncated singular value decomposition technique. Numerical example demonstrates the effectiveness and accuracy of the present algorithm.

Abstract: In this study, bentonite/polyacrylamide hybrid hydrogels were prepared via free radical polymerization of acrylamide (AM) with photocurable poly (ethylene glycol) dimethacrylate (PEGDMA) as cross-linkers under UV irradiation. The structure of the hydrogels was characterized by FTIR, DTA techniques. Both single factor and orthogonal design experiments were adopted to investigate the swelling kinetics of the hydrogels. The effect of AM, PEGDMA, bentonite, photoinitiator on the swelling ratios was studied in detail. The as-prepared hydrogels could find a lot of applications in biomaterials.

Abstract: In the paper, a stereo camera self-calibration method with Genetic Algorithm (GA) applied to the navigation of autonomous land vehicle (ALV) in a natural environment is proposed. The proposed method does not require specific object as a calibration pattern, e.g. checkerboard; conversely, it exploits common feature, for example: planes among natural scenes. In the evaluating process of GA, the coplanar condition of 3D points is employed as a fitness function to inspect the camera parameters. In addition, real valued GA is used because it does not only decrease the complexity of encoding and decoding process, but also increase the precision of solution. Comparing to conventional optimization methods, the camera self-calibration method based on GA can avoid being trapped in local minimum and does not need initial value or gradient information. Several experiments of the camera calibration with the stereo vision show that the proposed method can find approximate optimum solution.

Abstract: The paper proposed a new method that can real-time estimates the height of objects with a single camera from a bird’s–eye view. Generally, it is impossible to obtain 3-D information, like the depth of objects, with a single lens camera without the additional information, such as the height and the tilt angle of the camera, are known in advance [1]. The disparity map of binocular cameras is usually employed to estimate depth. It is not suitable for vehicles to estimate the height (similar to depth estimating from a planar view) of objects from a bird’s-eye view due to the difficulties of installing and corresponding. Therefore, the optical flow to estimate the height of the object with one camera is proposed. There are two features under a dynamic bird’s–eye view of image. First, the optical flow value is proportional to the height of the object. Second, there is no perspective effect in each layer height of an image plane. Several experimental results are included to show the proposed method is feasible.

Abstract: A difference-frequency mixer based on exclusive-or gates with a filter at the output, which processes a variable frequency input signal and a reference input signal (produced by measurement system) to develop an output signal representative of the frequency difference between the two input signals, was studied in theory and simulation experiments. Digital difference-frequency mixers of this kind can be used in the output signal measurement of resonator-based sensors for high resolution and short measure time.

Abstract: This article adopts a fuzzy and comprehensive assessment to analyze the indirect application effect of ERP system in JXCM through indirect application effect assessment index of ERP system from ERP system's implementation in national enterprises, draws a conclusion for assessment and makes further suggestions.

Abstract: Flotation recovery is an important index of flotation process, in order to change the existing detection methods of low accuracy , a soft measurement model of flotation recoveries is proposed based on improved weighted LS - SVM. According to the flotation foam characteristics and the corresponding relation of flotation recovery, the fuzzy C-means clustering method is used for flotation characteristics of data processing , the image characteristic values as prediction model input and using genetic algorithm to optimize the parameters of the model. The result show that the modified algorithm can overcome a prediction standard model LS - SVM algorithm parameter optimization shortage, and have better forecasting effect which provide effective protection for flotation process operation and flotation operation stable operation optimization .

Abstract: Land reclamation is an effective measure in recovering land resources, protecting ecological environment and solving the contradiction between people and land. This paper adopts ArcEngine, ArcSDE, Oracle, Micirosoft Visual C# and other technologies to develop mining subsided land reclamation system which integrates reclamation suitability evaluation model, ground deformation prediction model, land cube calculation model and economic evaluation model. The system realized the information and network management about mining subsided land, provided the functions such as map operation, ground deformation analysis, earth volume calculation, reclamation suitability evaluation and economic evaluation. It can be used to help decision maker choose and plan their activities more effectively and scientifically to match situation of land reclamation and ecological restoration.

Abstract: A new feedforward and feedback optimal control law for a class of nonlinear systems with persistent disturbances is presented in this paper. By using a successive approximation approach (SAA), the original nonlinear optimal control problem is transformed into a sequence of nonhomogeneous linear two-point boundary value (TPBV) problems. The optimal control law obtained consists of analytical linear feedforward and feedback terms and a nonlinear compensation term which is the limit of the solution sequence for the adjoint vector differential equations. By using the finite-step iteration of nonlinear compensation sequence, we can obtain a feedforward and feedback suboptimal control law. A disturbance observer is designed to get a physically realizable controller. Simulation examples show the effectiveness of the approach.

Abstract: Route guidance process is the dynamic game-based process of traffic authority and users, users’ behavior is affected by the guidance information and it also affect guidance effect. On the basis of analysis of user equilibrium and system optimum, a game theory model between traffic authority and users is presented, and system optimum and user optimum guidance strategy are given. Simulation results show that: user optimum guidance strategy will bring oscillation of traffic flow, system optimum guidance strategy is optimal but difficult to achieve, and coordination of system optimum and user optimum is close to system optimum strategy.