印刷维吾尔文特征提取之方向码

特征提取方法的选择是影响识别率的一个至关重要的因素。而印刷识别中的分类特征很多,让每一类特征具有良好的分类能力和稳定性是仍需要解决的问题。现就以具有高稳定性和抗干扰能力的八方向码特征为例,对其提取方法进行了全面的阐述。     

Instability of Curved Beams Made of Functionally Graded Material Under Thermal Loading

In this paper the thermal buckling load of a curved beam made of functionally graded material (FGM) with doubly symmetric cross section is considered. By instability conditions we mean the in-plane and out-of-plane buckling. The stability equations are derived using the variational principles. The curved beam is under temperature rise for thermal loading. The solution for critical thermal buckling load is obtained using the stability equations and the Galerkin method. The critical thermal buckling load is obtained.     

Artificial neural network based autoregressive modeling technique with application in voice activity detection

A new method of estimating the coefficients of an autoregressive (AR) model using real-valued neural network (RVNN) technique is presented in this paper. The coefficients of the AR model are obtained from the synaptic weights and adaptive coefficients of the activation function of a two layer RVNN while the number of neurons in the hidden layer is estimated from over-constrained system of equations.The performance of the proposed technique has been evaluated using sinusoidal data and recorded speech so as to examine the spectral resolution and line splitting as well as its ability to detect voiced and unvoiced data section from a recorded speech. Results obtained show that the method can accurately resolve closely related frequencies without experiencing spectral line splitting as well as identify the voice and unvoiced segments in a recorded speech.     

具有抗氧化性能的环境友好型油酸盐（钙、镁）清净剂的合成

This article covers a method for synthesizing environmentally friendly multifunctional metal (calcium,magnesium) oleate detergents with antioxidation property.These multifunctional metal (calcium,magnesium) oleate detergents with antioxidation property were synthesized using oil-soluble liquid antioxidants (PPIBP,PPIBTSTBP,and PPIBPDA) as reactive functional materials.These oil-soluble liquid antioxidants have the potential to be used as functional materials for application in synthesizing other kinds of substrate detergents.     

一种新的整定方法用于参数不确定条件下二自由度内部模型控制(英文)

Internal model control （IMC） yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC （2DOF-IMC） has been developed to overcome the weakness. However, the setting of parameter becomes a complicated matter if there is an uncertainty model. The present study proposes a new tuning method for the controller. The proposed tuning method consists of three steps. Firstly, the worst case of the model uncertainty is determined. Secondly, the parameter of set point con- troller using maximum peak （Mp） criteria is specified, and finally, the parameter of the disturbance rejection con- troller using gain margin （GM） criteria is obtained. The proposed method is denoted as Mp-GM tuning method. The effectiveness of Mp-GM tuning method has evaluated and compared with IMC-controller tuning program （IMCTUNE） as bench mark. The evaluation and comparison have been done through the simulation on a number of first order plus dead time （FOPDT） and higher order processes. The FOPDT process tested includes processes with controllability ratio in the range 0.7 to 2.5. The higher processes include second order with underdarnped and third order with nonminimum phase processes. Although the two of higher order processes are considered as difficult processes, the proposed Mp-GM tuning method are able to obtain the good controller parameter even under process uncertainties.