Key Engineering Materials Vols. 480-481

Abstract: For a model elliptic boundary value problem in three dimensions, we give the weak estimates for the quadratic block finite element with twenty-six degrees of freedom (QBFETSDF). Combined with the estimates for discrete Green’s function, we get maximum norm error estimates for the QBFETSDF.

Abstract: This essay explores the often encountered quality problems of the box-shaped piece in drawing and the relative control measures. Detailed analysis and numerical simulation of using better materials, optimizing the blank shape, taking appropriate pressure-pad-force and suitable drawing equipments are provided. This essay is helpful for the improvement of the drawing formation quality.

Abstract: In this paper, an upsetting problem is analyzed by using a new meshless method called the overrange collocation method (ORCM). By introducing some collocation points, which are located at outside of domain of the analyzed body, unsatisfactory issue of the positivity conditions of boundary points in collocation methods can be avoided. Because the overrange points are used only in interpolating calculation, no over-constrain condition is imposed into solved boundary value problems.

Abstract: This essay discusses the necessity of introducing the concurrent engineering into the multi-stationed progressive die development and the relative procedures. And the detailed multi-stationed die progressive development of the rotors and stators on the micro-motors is provided. And the conditions of the concurrent development on the multi-stationed die are offered.

Abstract: In this paper, the stabilization problem is studied by using multiple Lyapunov function techniques for a class of discrete-time switched linear singular (DSLS) systems. The existing criteria of stability for continuous-time switched singular systems are extended into DSLS systems. Then, a hybrid switching law is designed based on a partition of state space by using S-procedure method.

Abstract: The correlation distance is one of the important parameters for the application of random field theory to reliability analyses. Soil spatial variability is related to soil point variability with the reduction factor of variance in random field theory, and the reduction factor of variance depends on both soil auto-correlation distance and spatial area. The sampling space effect on auto-correlation distance is studied. The vertical and horizontal correlation distances of typical stratum are analyzed in statistics based on a large amount of investigation data and the representative values of correlation distance of local area are obtained. It is concluded that that the correlation distances estimated by different soil parameters are similar, and the horizontal correlation distance is much larger than the vertical one for the same soil parameter. The sampling space should be paid attention to when calculating correlation distance of soil parameter.

Abstract: Signal source separation (SSS) has widely been adopted for magnetoencephalography (MEG) to reduce external magnetic noise interference. The basic idea of SSS is based on decomposing measured fields into spherical harmonic bases. Due to the feature, the performance of SSS strongly depends on the shape of a measuring sensor array. In this article, we show the noise reduction performances in several different shapes of the sensor and array and demonstrate SSS is only effective for a non-spherical sensor array or for a gradiometric arrangement.

Abstract: For the case of the scheme trajectory command design for the tactical missile, the longitudinal and lateral commands and the compound controller of the attitude and height were designed. In the launch segment, four kinds of heading angle commands were presented adopting the arc method and reduction law. In the variable height flight segment, two kinds of height commands were gained by using the parabolic and exponential function. Considering the earth curvature, the formula of the great circle course and distance was gotten applying spherical triangle solution method, and the flight command along the route dot in the lateral plane was obtained. The simulation results show that the designed scheme trajectory commands are feasible and effectively.

Abstract: Furnace as a control system whose conditions complex, parameter changing , great runing inertia ,control action delay . Of which there are many uncertainties ,such as air, fuel gas pressure and the frequent fluctuations of the fuel’s calorific value . The impact of mutual interference and coupling between the variables to the furnace can not be ignored , though it’s not dominant .The systerm based on control model use an advanced generalized predictive control (GPC) algorithm control mode .It can improve the control accuracy of regulator action when the furnace is at the condition of stability .The experiment results show that ducoupling GPC algorithm has a good convergence effect .

Abstract: The gold mine discharges tailings massively every day,which results in gold and useful metal draining,simultaneously brings the enormous harm to the environment The approach to comprehensive utilization of tailings of gold mines, including recycle of usable mineral and direct use of ore tailings,is analyzed in the paper, laying a foundation for continuous development of gold mines，comprehensive utilization of resource，and protection of environment.