Applied Mechanics and Materials Vols. 204-208

Abstract: This study is based on UG and finite element simulation software VPG and LS-DYNA to simulate,finally get how the automotive quality,impact speed and angle influence on rounded cutting edge rules of CST and collision characteristics .So provide a strong basis to the application of CST and car safety.

Abstract: In this paper, A class of third-order nonlinear neutral damped functional differential equations with distributed deviating arguments are studied. By using a generalized Riccati transformation and Kamenev-type or Philos-type integral averaging technique,we establish some new sufficient conditions which insure that any solution of this equation oscillates or converges to zero.

Abstract: Based on equivalent continuum media theory of fractured rock mass, the author got the permeability tensor of floor strata in some mine according to core logging method, drilling imaging method and boring water injection method, and determined the floor rock permeability tensor using correction method. The author simulated the floor inrush problem by coupling fluid-solid theory and anisotropic flow model with FLAC3D software. The result shows that, the destroyed depth of floor and the confined water rising height are all slight when the coal mining workface is 150m apart from the fault, but they increase obviously when the coal mining workface is 30m apart from the fault, and are extremely easy to get through and casue water inrush through fault.

Abstract: Portable exoskeleton is directed at providing necessary support and help for loaded legged locomotion. The kernel of whole mechanical construction of the exoskeleton is lower extremities. The lower extremities consist of exoskeleton thigh, exoskeleton shank, hydraulic cylinder and corresponding joints. In order to find the optimal combination of design parameters of lower extremities, an improved particle swarm optimization algorithm based on simulated annealing is proposed. To improve global and local search ability of the proposed approach, the inertia weight is varied over time, and jumping probability of simulated annealing is adopted in updating the position vector of particles. Experimental results show that the improved algorithm can obtain the optimal design solutions stably and effectively with less iteration compared to the standard particle swarm optimization and simulated annealing; using ANSYS software build finite element model with the optimization result, then analyzes the strength of the model, these stress results verify the of accuracy of the improved particle swarm optimization.

Abstract: The distribution of metallogenic elements grade is an effective index for the quantitatively economical evaluation of mineral resources. We have defined the information entropy as a measure of randomness of metallogenic elements grade distribution, assumed its primary distribution is in an extremely random situation, and deduced the density function of the primary distribution based on maximum entropy principle. Considering the fact that elements concentration goes from a non-orderly state to an orderly one in the ore-forming process, we added restraint parameters to the primary distribution model, got a two-parameter Weibull distribution model with embedded fractal features, and then fitted metallogenic element's grade distribution of Ag-Cu-Pb-Zn from a mine in China. The results show that the Weibull model is more effective than a lognormal model to describe elements distribution, and should be applied more broadly than common lognormal models in geology discipline.

Abstract: The integrated optimization of structure and control systems is investigated for 2-D single structure using a typical planar frame taken from a building. The vibration control model is established for the plane frame, and the LQR algorithm is used to obtain equivalent stiffness and damping parameters of assigned passive controllers. The integrated optimization model, including design variables, the objective function and constraint function, is built. The design variables are the size parameters of structural elements, the parameters of the weighted matrix, the number and locations of the controllers. The maximal displacement of the controlled system in time domain is introduced as the objective function. Genetic algorithm is adopted to solve such a kind of optimization problem with discrete and continuous design variables. The results of a numerical example show that the proposed method is reasonable and effective for the integrated design of control/structural systems subjected to seismic load.

Abstract: The theory of expectation estimation is put forward to discuss the estimation quality of the expectation domain. It is demonstrated that the “validity” criterion of the estimation theory in mathematical statistics (named classic estimate later) isn’t right and arithmetical average value x isn’t the best estimate. The means of characteristic value estimate (N (0, 1) estimate) is suggested to demonstrate the expectation estimate domain.

Abstract: By analyzing the attributes of three-dimensional space data model, the integrated 3D spatial data adopts object-oriented method for digital landslide modeling. It achieves spatial data modeling for landslide geological entity. An experimental case is given to indicate the feasibility of this approach for spatial data modeling.

Abstract: Artificial bee colony algorithm (ABC) is a newly swarm intelligence optimization algorithm. It has become a powerful tool for solving highly nonlinear multi-peak optimization problems. The results of performances testing using three benchmark functions show that the numbers of evaluation for fitness function of ABC are obviously less than that using particle swarm optimization algorithm. Thus, ABC has better suitability for solving multi-modal optimization problems. Finally, ABC algorithm is applied to the load distribution calculation of pile group. The result shows that the ABC is feasible and has the advantages of high efficiency and easy implementation

Abstract: The numerical simulation of construction is to obtain the desired accuracy. It depends on the theoretical basis of the calculator and selection of the various important factors in the actual operation. For this problem, this paper adopting the current code for the design of building structures as the comparison standard, using the FLUENT software, taking the numerical simulation results of a high building’s wind load shape coefficient of for example, discussing the influence of four kinds of the convective terms discretization scheme, respectively the first-order upwind, the second order upwind , power law and Quadratic upwind interpolation for convective kinematics, on the simulation results of architectural numerical wind tunnel, provides the reference for the rational use of numerical wind tunnel method.