Origin软件在化学工程实验中的应用

物理化学实验和化工原理实验是化学工程专业的基础学科实验。介绍了运用Origin软件对物理化学和化工原理实验结果进行数据处理和图像绘制的方法。     

Stock trend prediction based on a new status box method and AdaBoost probabilistic support vector machine

Stock trend prediction is regarded as one of the most challenging tasks of financial time series prediction. Conventional statistical modeling techniques are not adequate for stock trend forecasting because of the non-stationarity and non-linearity of the stock market. With this regard, many machine learning approaches are used to improve the prediction results. These approaches mainly focus on two aspects: regression problem of the stock price and prediction problem of the turning points of stock price. In this paper, we concentrate on the evaluation of the current trend of stock price and the prediction of the change orientation of the stock price in future. Then, a new approach named status box method is proposed. Different from the prediction issue of the turning points, the status box method packages some stock points into three categories of boxes which indicate different stock status. And then, some machine learning techniques are used to classify these boxes so as to measure whether the states of each box coincides with the stock price trend and forecast the stock price trend based on the states of the box. These results would support us to make buying or selling strategies. Comparing with the turning points prediction that only considered the features of one day, each status box contains a certain amount of points which represent the stock price trend in a certain period of time. So, the status box reflects more information of stock market. To solve the classification problem of the status box, a special features construction approach is presented. Moreover, a new ensemble method integrated with the AdaBoost algorithm, probabilistic support vector machine (PSVM), and genetic algorithm (GA) is constructed to perform the status boxes classification. To verify the applicability and superiority of the proposed methods, 20 shares chosen from Shenzhen Stock Exchange (SZSE) and 16 shares from National Association of Securities Dealers Automated Quotations (NASDAQ) are applied to perform stock trend prediction. The results show that the status box method not only have the better classification accuracy but also effectively solve the unbalance problem of the stock turning points classification. In addition, the new ensemble classifier achieves preferable profitability in simulation of stock investment and remarkably improves the classification performance compared with the approach that only uses the PSVM or back-propagation artificial neural network (BPN).     

实木顺纹压缩弯曲技术研究现状及发展趋势

实木顺纹压缩弯曲技术蕴含着多学科知识的交叉融合,具有一定的理论深度和突出的实际应用性,是当今备受关注的研究热点之一文章论述了国内实木顺纹压缩弯曲技术的研究现状与发展趋势,描述了国内研究学者在树种选择、木材软化与顺纹压缩、木材弯曲等方面的研究成果,提出高效利用木材资源、提升自动化程度、提高木材弯曲精度的发展趋势,为今后国内实木顺纹压缩弯曲技术的研究提供借鉴。     

Detection of linear trends in process mean

In this paper, we develop a process control approach to detect linear trends in the process mean. A statistic based on the deviation between the target mean and the expected mean of the process is used in the development of the new approach. The statistic is shown to have a chi-square distribution. The approach is described and its performance is compared with cumulative sum (CUSUM), exponentially weighted moving average (EWMA), Shewhart, and generalized likelihood ratio (GLR) charts in detecting linear trends in the process mean. The results indicate that proposed approach is effective in detecting small to large trends. We also investigate the run length properties of the proposed approach under linear trends and compare its values with simulation results. Finally, we analyse the performance of the proposed approach in detecting the time when a drift occurs in the process and compare it with CUSUM and EWMA estimators. The results show that the proposed approach is more effective in detecting drift time for moderate and large trends.     

全球能源变局下的石油石化业发展动向

世界能源结构正在发生变化,石油比例在下降,天然气在页岩气的带动下快速发展,份额上升,生物能源迅速崛起。石油石化行业也相应呈现出业务布局调整,发展重心东移,产业装置规模大型化,清洁燃料标准趋严,节能减排要求提高,生物燃料、天然气及煤化工等能源多元化发展的新趋势。论述了全球能源结构的变化趋势以及世界石油石化行业的最新发展动向。     

基于技术进化趋势的裁剪方法研究

裁剪是TRIZ中一种有效解决问题的方法,其通过删除问题元件,重组系统有用功能进行产品创新设计,达到简化系统与优化产品的目的.为了启发和引导设计者在裁剪过程中有效地利用资源,在使用裁剪规则引导创新设计的基础上,以具有预测性和启发性的技术进化趋势作为知识源,综合分析进化趋势解题与裁剪规则引导功能重组的资源来源,构建了进化趋势与裁剪规则的映射关系,提出了基于裁剪规则的多层次进化趋势选择策略,利用进化趋势辅助功能重组,构建了基于进化趋势的裁剪方法过程模型.最后通过钢带铠装机裁剪实例验证了此方法的合理性.     

含聚污水中聚丙烯酰胺含量测定

采用EGM2008重力场模型和趋势面拟合与基于正交最小二乘思想筛选节点的多面函数法,运用移去恢复原理建立了太原市区的似大地水准面模型,拟合得到的模型内符合与外符合中误差均小于2 cm,完全可以满足太原市区内常规测量的要求。     

纸质家具设计的发展趋势研究

以纸质家具相对实木、藤、金属类家具具有质轻、环保、经济、舒适、时尚的优点为启示,论述纸质材料在家具设计行业中研发与应用的重要性。并在此基础上,提出了纸质这种"可持续性"材料应用在家具设计中,能够体现家具设计的环保新理念,并根据纸质家具目前还存在的一些缺点和未来欧洲家具设计发展方向,概括出纸质家具设计在未来几年内的发展趋势。     

基于CT的骨骼三维打印技术的发展现状与趋势

基于CT的骨骼二维打印技术足近几年提出的新兴技术,是目前制造生物活性人工骨骼的有效方法.通过对二维打印技术发展现状和CT扫描数据导入三维打印机的特点、难点的研究,分析三维打印技术制作生物活性骨骼存在的问题,提出了三维打印技术应用于人体骨骼制作的发展趋势.     

线阵声诱饵对抗具有尺度识别能力鱼雷的分析与仿真

为了研究线阵声诱饵对抗具有尺度识别能力鱼雷的性能,以分裂波束和方位走向法为例,分析了鱼雷对尺度目标回波的识别方法,以此为基础探讨了线阵声诱饵在对抗具有尺度识别能力鱼雷时的若干技术问题,通过仿真验证了线阵声诱饵对抗尺度识别能力鱼雷的有效性。本文证明了线阵式的声诱饵可以有效模拟舰船目标的尺度特征,在对抗有尺度识别能力的鱼雷时是很有意义的发展方向。本文所给出的仿真方法,除了建立线阵诱饵在诱骗有尺度识别功能鱼雷的仿真模型外,还可以作为物理模型应用在诱饵工作程序中,提供各阵元的延迟时间等声学参数。