花生壳中总黄酮和木犀草素提取工艺研究

研究花生壳中总黄酮和木犀草素的提取工艺.经正交试验,以提取物中总黄酮和木犀草素含量为评价指标.优选提取工艺.确立以75%乙醇为溶剂,料液比1:10,每次提取2h,提取3次为优选工艺,花生壳中总黄酮和木犀草素均可有效提取.该工艺简捷、经济、可行,适合工业化生产.     

非正弦时域正交调制系统性能分析

为了正确地进行非正弦时域正交调制通信系统解调,利用脉冲间的时域正交性分离调制脉冲。通过对非正弦时域正交调制通信系统的性能以及脉冲组间互相关特性的分析,特别是针对脉冲组正交性被破坏的情况下,分析了影响其性能的因素,提出了在调制端采用选择脉冲的方法,在一定程度上改善了系统的性能。     

A Perfect Reconstruction, Size-Limited Filter Bank for Orthogonal, Wavelet-Based, Finite-Signal Subband Processing

Tang, J., and Zhang, Y., A Perfect Reconstruction, Size-Limited Filter Bank for Orthogonal, Wavelet-Based, Finite-Signal Subband Processing, Digital Signal Processing11 (2001) 304–328This paper describes a new scheme to design the size-limited filter banks for orthogonal wavelet-based, finite-signal subband processing. In contrast to the existing schemes based only on boundary extension, our scheme combines boundary extension with boundary filter amendment. The advantages of our scheme lie in that we can guarantee the perfect reconstruction, independence, and orthogonality of the size-limited filter banks.     

Suppression of higher harmonics resonance in a distribution system

There are many PWM control devices, which are higher harmonics current sources, in distribution systems, and higher harmonics cause overcurrents by parallel resonance. To avoid overcurrents, it is necessary to suppress resonance. In this paper, a new suppression method, which uses the effect of source connected points in resonance circuits, is proposed. First it shows that the optimal point, which gives a minimum current amplification degree, is orthogonal to the static condenser voltage. Then, using the eigenvector of the state equation, the participation factor is defined. When the participation factor is zero, the orthogonality condition is introduced. Therefore, the optimal point is obtained with the participation factor. Finally, numerical investigation shows that multiple optimal points usually exist. Therefore, we can choose the most advantageous point as a source‐connected node. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 182(1): 18–29, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22307     

复合有限条法研究水压作用下加肋柱壳的后屈曲

为了研究水压作用下的加肋柱壳的后屈曲状况,并且能考虑到肋骨的实际截面形状和分布情况,本文将复合有限条方法应用于环加肋圆柱壳的后屈曲分析。在对后屈曲路径的跟踪过程中,使用了正交弧长法。算例表明,复合有限条方法同纯粹的有限元方法相比在速度上能提高10倍以上,并且方程阶数与壳体尺寸无关,是一种分析加肋板壳结构的理想方法;实际应用的加肋圆柱壳在水压下的后屈曲路径一般来说不存在分叉点,在后屈曲阶段,随着变形的增加常常要求压力有所增加。     

AN OPTIMIZATION OF EIGENFUNCTION EXPANSION METHOD FOR THE INTERACTION OF WATER WAVES WITH AN ELASTIC PLATE

The hydroelastic interaction of an incident wave with a semi-infinite horizontal elastic plate floating on a homogenous fluid of finite depth is analyzed using the eigenfunction expansion method. The fluid is assumed to be inviscid and incompressible and the wave amplitudes are assumed to be small. A two-dimensional problem is formulated within the framework of linear potential theory. The fluid domain is divided into two regions, namely an open water region and a plate-covered region. In this paper, the orthogonality property of eigenfunctions in the open water region is used to obtain the set of simultaneous equations for the expansion coefficients of the velocity potentials and the edge conditions are included as a part of the equation system. The results indicate that the thickness and the density of plate have almost no influence on the reflection and transmission coefficients. Numerical analysis shows that the method proposed here is effective and has higher convergence than the previous results.     

CDMA2000反向链路正交系统性能研究

基于现有CDMA2000信道结构,研究了反向链路正交方案,并利用rise-over-thermal(ROT)准则对该系统容量进行了分析。数值计算结果和动态系统级仿真表明,与非正交反向链路对比,采用反向链路正交降低了来自本小区的干扰,使系统容量有显著提高,但可用正交码资源限制了这种增益。     

基于广义正交概念的K-RANSAC椭圆提取

开发了一个使用广义正交概念的K-RANSAC椭圆提取算法.该算法通过使用广义正交概念,成功地把圆的所有性质推广到椭圆;通过仿射变换把水平-垂直种子点对一般化为任意种子点对情况;通过对边缘点集的归一化运算,有效地正则化了提取椭圆的边缘点集的病态性;通过直接估计椭圆参数的广义本征分析技术,进一步提高椭圆的可检测性和拟合精度.理论分析和实验结果表明,所开发的椭圆提取算法具有鲁棒性强、适用范围广、精度高和速度快等优点.     

B样条正交小波的构造

基于Mallat多尺度分析理论,用Daubechies的正交小波构造方法,构造出任意阶基数B样条规范小波,并给出了相应的小波函数,尺度函数,正交象波器H和G的时频响应表达式,这类小波产生的小波基适用于一维和二维信号分解与重建过程中的Mallat快速算法。     

被动检测系统中自适应算法收敛的动态判断

被动检测应用中，实际环境条件往往比较恶劣而且不可预测，非平稳干扰随时可能发生，如不能准确判断自适应系统实际收敛状况，检测结果将受到严重影响。在实际复杂噪声环境影响下，时间常数已不能代表系统的实际收敛特性，因此提出一种动态判断自适应检测系统迭代算法收敛的方法。基于自适应滤波器工作在理想最优条件时的正交原理，推导出考虑梯度噪声影响时误差与输出信号实际近似正交的约束条件，根据每次迭代不断更新的期望、输出及误差信号的均方估计，在线实时判断收敛并评估自适应解的质量，及时准确停止迭代以得到最佳检测结果，从而避免复杂背景干扰的影响。此动态判断条件对平稳与非平稳环境中的自适应检测均适用，不同条件下的处理结果验证了该方法的有效性。