融合模拟退火的随机森林房价评估算法

传统的随机森林房价评估算法存在着大量参数组合计算问题,参数的优劣对算法准确度影响很大。针对此问题,结合随机森林和模拟退火算法提出一种融合模拟退火的随机森林房价评估算法。首先,通过10次10折交叉验证法对参数进行敏感性测试,选择出对随机森林算法敏感的参数;然后结合模拟退火算法对敏感的参数迭代寻优,通过与网格搜索算法、随机搜索算法进行对比分析发现,在参数组合计算过程中,模拟退火算法在运行时间和算法准确率方面更优,弥补了网格搜索算法耗时过长和随机搜索算法低准确率的缺陷;最后,将融合模拟退火的随机森林算法应用于房价评估问题,构成新的房价评估算法。将新算法与传统随机森林房价评估算法进行了对比实验分析,结果表明,融合模拟退火的随机森林房价评估算法误差值减少,拟合优度值增加,评估的准确度得到了显著提升。     

物流自动化管理系统的数据库设计

为实现仓储物流自动化管理系统的入库、出库、报表、储位查询、物品查询、客户查询、仓库及人员管理模块等功能模块,本文采用SQLSEVER2000数据库管理系统、微软公司的VS.NET的C#开发工具,利用其提供的各种面向对象的开发工具,其中最主要的是ADO.NET技术实现了基于电子标签技术的物流自动化管理系统后台数据库方面的开发任务。现场试验表明:本文所设计的物流自动化管理系统达到了预期要求。     

基于Elman神经网络的股票价格预测研究

为了更好地把握股票价格的波动，应用了在处理序列数据输入输出具有优越性的Elman 递归神经网络建立股市预测模型，并用两支股票进行了检测，检测结果说明人工神经网络应用于中国股票市场的预测是可行和有效的，有着良好的前景。     

A PTAS for Cutting Out Polygons with Lines

We present a simple O(m+n ⁶/ε ¹²) time (1+ε)-approximation algorithm for finding a minimum-cost sequence of lines to cut a convex n-gon out of a convex m-gon.     

A bat-neural network multi-agent system (BNNMAS) for stock price prediction: Case study of DAX stock price

Creating an intelligent system that can accurately predict stock price in a robust way has always been a subject of great interest for many investors and financial analysts. Predicting future trends of financial markets is more remarkable these days especially after the recent global financial crisis. So traders who access to a powerful engine for extracting helpful information throw raw data can meet the success. In this paper we propose a new intelligent model in a multi-agent framework called bat-neural network multi-agent system (BNNMAS) to predict stock price. The model performs in a four layer multi-agent framework to predict eight years of DAX stock price in quarterly periods. The capability of BNNMAS is evaluated by applying both on fundamental and technical DAX stock price data and comparing the outcomes with the results of other methods such as genetic algorithm neural network (GANN) and some standard models like generalized regression neural network (GRNN), etc. The model tested for predicting DAX stock price a period of time that global financial crisis was faced to economics. The results show that BNNMAS significantly performs accurate and reliable, so it can be considered as a suitable tool for predicting stock price specially in a long term periods.     

基于三角面模型的虚拟轮廓铣削仿真研究

针对基于三角面片构建的带内腔毛坯模型,在轮廓铣削仿真时,由于在不完全被切除的三角面片中未被切除顶点的不移动,所造成被切削轮廓面不光顺的问题,提出了沿刀具切削包络面的法向,未被切除的顶点移动到包络面上的方法,解决了轮廓面不光顺的问题;而对于仿真铣削带内腔毛坯时,就内外表面如何关联的问题,首先提出了判断刀具进出模型内外表面的算法,然后给出了轮廓面与内腔面关联的方法,完善地解决了这一问题.基于本研究提出的方法,通过VirtoolsDev开发平台,对带内腔的三角面片模型,获得了具有光顺切削表面的仿真效果.同时,使得铣削仿真精度也得到了根本性的改善.     

基于神经网络的股市预测

本文讨论了有关神经网络用于股市预测方面的问题，包括股市原始数据的预处理、训练样本的确定。提出了适合于描述股市动态特性和时序特性的网络模型及学习算法，并对上海股市作了实际的预测。实验结果表明本文提出的方法是可行的和有效的。     

C语言程序结构设计的新方法——函数软件包的建立

本文着重介绍一种如何建立用户扩展函数库(即用户函数软件包)的方法.使之成为C语言软件设计强有力的手段之一.UNIX操作系统上C语言提供给用户大量的可供选择的UNIX C库函数,这些库函数可以直接调用.但是.系统C库函数往往不能满足一些用户的特殊需求.所以函数软件包的开发具有很高的实用价值.     

PRINCIPLES OF ECONOMIC GROWTH

The economic system is viewed as a complex system of actors that interact by competition and coalition. Its evolution is described by morphodynamics, a general theory based on the thermodynamics of physical systems. The economic system then is represented as exchanging services and monetary signs with its environment, namely people. These exchanges are ruled by principles analogous to the principles of thermodynamics. Thus, reversible exchanges found a theory of money supply, wages and prices, whereas irreversible exchanges account for monetary profits, inflation and the long term growth of the economy.     

A class of continuous-time portfolio selection with liability under jump-diffusion processes

A continuous-time mean-variance portfolio selection model is formulated with multiple risky assets and one liability under discontinuous prices which follow jump-diffusion processes in an incomplete market. The correlations between the risky assets and the liability are considered. The corresponding Hamilton–Jacobi–Bellman equation of the problem is presented. The optimal dynamic strategy and the efficient frontier in closed forms are derived explicitly by using stochastic linear-quadratic control technique. Finally, the effects on efficient frontier under the value-at-risk constraint are illustrated.