复变函数几何理论的某些结果

本文扼要介绍西北大学数学系复分析科研小组部分教师在复变函数几何理论研究方面的一些成果。它主要包括系数问题;亚纯单叶函数;某些特殊函数族;极值点和支撑点以及积分平均和反系数问题共5个部分。     

Support Vector Machine-Based Nonlinear System Modeling and Control

This paper provides an introduction to a support vector machine, a new kernel-based technique introduced in statistical learning theory and structural risk minimization, then presents a modeling-control framework based on SVM. At last a numerical experiment is taken to demonstrate the proposed approach's correctness and effectiveness.     

老年人临终关怀的现状与需求--以济南市为个案的调查报告

临终关怀是任何一个明社会都不可忽视的社会问题，研究老年人的临终关怀是社会明的需要，更是每一个进入老龄化社会的国家的需要。它有利于增进社会的明，提高人们的尊严与价值。通过对济南市老年人临终关怀的调查，了解了我国老年人临终关怀的现状与问题，并由此提出了意见与建议。     

FORECASTING NIKKEI 225 INDEX WITH SUPPORT VECTOR MACHINE

Support Vector Machine (SVM) is a very specific type of learning algorithms characterized by the capacity control of the decision function, the use of the kernel functions and the sparsity of the solution. In this paper, we investigate the predictability of financial movement direction with SVM by forecasting the weekly movement direction of NIKKEI 225 index. To evaluate the forecasting ability of SVM, we compare the perfor-mance with those of Linear Discriminant Analysis, Quadratic Discriminant Analysis and Elman Backpropagation Neural Networks. The experiment results show that SVM outperforms other classification methods. Furthermore, we propose a combining model by integrating SVM with other classification methods. The combining model performs the best among the forecasting methods.     

基于RBF神经网络与遗传算法的Agent初始位置优化

以陆地作战训练模型为背景，研究了多Agent系统中Agent初始属性的优化问题，提出了一种径向基函数(RBF：Radial Basis Function)神经网络与遗传算法(GA：Genetic Alorithm)相结合的、对作战训练模型中Agent的初始位置进行优化的方法。与已有的优化方法相比，该方法不仅优化效果得到明显的提高，而且执行效率可以提高20余倍，更适于处理对执行效率要求较高的优化问题。     

Active set strategy of optimized extreme learning machine

Extreme learning machine （ELM） has been introduced as a simple and efficient learning approach for regression and classification applications. From the opti- mization point of view, optimized ELM is equivalent to SVM, but with less constraints in the optimization formu- lation and random ELM kernel. This paper introduces an active set based optimized ELM approach to solve bound constrained optimization problem in a straightforward way, which operates on a small working set of variables at each iteration. Thus, the constrained problem can be eventually solved by an unconstrained algorithm, and this enables us to establish a global convergence theory. The approach requires less time for quadratic programming solving and provides better generalization performance. In addition, the proposed approach with much smaller number of non- bound support values is significantly faster than SVM with active set strategy for large training data set.     

一种新的支持向量机增量学习算法

支持向量机学习算法的本质是从训练集中寻找支持向量,因此能否通过训练算法能快速找出支持向量是衡量支持向量机算法优劣的重要标准.本文提出了一种新的快速训练支持向量机的增量学习算法,首先,给出边界向量的定义,然后,对一个给定的新加人的样本,新的学习方法验证其是否为边界向量,如果是,将其加入到训练集中重新训练支持向量机,如果不是,就舍弃,这样能达到减少训练样本、降低训练复杂性目的,最后,给出了一个增量学习算法.实验表明测试误差和支持向量数量与SMO算法大致相当,而训练速度明显加快.     

Quantum-inspired evolutionary tuning of SVM parameters

The most commonly used parameters selection method for support vector machines （SVM） is cross-validation, which needs a long- time complicated calculation. In this paper, a novel regularization parameter and a kernel parameter tuning approach of SVM are presented based on quantum-inspired evolutionary algorithm （QEA）. QEA with quantum chromosome and quantum mutation has better global search capacity. The parameters of least squares support vector machines （LS-SVM） can be adjusted using quantum-inspired evo- lutionary optimization. Classification and function estimation are studied using LS-SVM with wavelet kernel and Gaussian kernel. The simulation results show that the proposed approach can effectively tune the parameters of LS-SVM, and the improved LS-SVM with wavelet kernel can provide better precision.     

基于信息增益的中文网页SVM分类研究

针对中文网页文本分类中特征降维方法和传统信息增益方法的缺陷和不足做出优化改进,旨在有效提高文本分类效率和精度.首先,采取词性过滤和同义词归并处理对特征项进行初次特征降维,然后提出改进的信息增益方法对特征项进行特征加权运算,最后采用支持向量机(SVM)分类算法对中文网页进行文本分类.理论分析和实验结果都表明本方法比传统方法具有更好的性能和分类效果.     

态射范畴中的极大rigid对象

对任意的域k上的有限维代数A, 记M为A的有限生成投射模的态射范畴.本文利用A的支撑\tau-倾斜模给出了M 的极大rigid对象的分类.特别地, M中的任意的基本的极大rigid对象的不可分解直和项个数恰为2|A|.