The Low-rank Matrix Completion Based on S_1/2 Modeling and the Research of its APG Algorithm

低秩矩阵填充问题（Low-rankMatrixCompletion）是指对于有部分位置上元素未知的矩阵，在假设矩阵低秩的前提下，可以通过优化算法来将其填充成一个完整的矩阵。低秩矩阵填充在机器学习、图像处理、推荐系统等领域发挥着重要的作用，是现今处理海量、高维数据的有力分析工具。本文首先介绍了低秩矩阵填充模型的理论发展，再分别根据将原模型进行凸松弛和非凸松弛后的改进模型综述了目前主要的算法，其中包括凸松弛的SVT算法，APG算法，ALM算法和非凸松弛的WMMN模型，并分析说明了不同算法在不同的领域，针对不同的模型有着各自的优势。 目前主要用于解决低秩矩阵填充的模型是用矩阵核范数来逼近目标函...Low-rank matrix completion refers to problem that use optimization algorithm to fill a matrix which have unknown elements into a complete matrix.In general,we assume the incomplete matrix is a low-rank matrix.This methods have played an important role in areas such as machine learning, image processing, recommendation systems and so on,it's a powerful analysis tool of high-dimensional data.In this...学位：理学硕士院系专业：数学科学学院_应用数学学号：1902014115262

Study on the IPO Underpricing Problem of the GEM Based on the BP Neural Network Theory

2009年10月23日，创业板在酝酿了十年之后成功启动，给我国资本市场注入了一股新的活力，由此我国资本市场向着“多层次”的目标又跨了一大步。创业板为我国具有“三高五新”特征的企业提供了一个稳定高效的融资平台，在我国资本市场上具有极其特殊又重要的地位。 从国际股票市场的现状来看，新股的发行价格往往都会偏离二级市场首日收盘价，从而产生抑价现象。但是作为新兴经济体中的新兴资本市场，创业板市场的IPO抑价现象尤为突出。由于我国创业板开板时间较短，对于创业板IPO抑价现象鲜有系统的梳理和研究，尤其考虑到企业内在因素和外在因素可能以复杂非线性的方式对IPO定价和二级市场股票价格产生影响，因此本文尝试在借...Growth Enterprise Market (GEM) set up after ten years' research on October 23, 2009, which injected a stream of new vitality to our capital market. Thus our capital market made a great stride towards the goal of multi-levels. The GEM board provides a stable and efficient financing platform for these enterprises who have the characteristics of high-technology, high growth, high value-added and new ...学位：经济学硕士院系专业：经济学院财政系_资产评估学号：1552008115191

ADVANCES IN CHROMASOME RESEARCH IN MARINE ZOOPLANKTON IN CHINA

国家自然科学基础研究重大项目G1999043708

Technical advances in space cell bioreactor

为了研究空间微重力环境对生命系统的影响,在空间进行细胞生物学实验是不可或缺的环节。空间细胞生物反应器作为支持空间生命科学研究的重要技术手段,直接影响到空间实验数据的质量和研究水平。迄今为止,空间细胞生物反应器技术仍在发展之中.,尚无统一标准。综述空间细胞生物反应器发展的现状,介绍几类典型空间细胞生物反应器的工作原理,着重分析培养液供应方式和空间流体力学环境的特点,并简要分析对温度、溶氧、溶液PH值等过程参数控制及在线显微观测技术,以期探讨空间生物反应器的未来发展方向。</p

〔報文〕敦煌莫高窟第53窟の窟内環境―温湿度実測調査と気流解析―

Environmental investigation at Cave 53, Mogao Grottoes, has been conducted from 2004. Air temperature and relative humidity at several points in the cave were measured from 2003 to 2006. Based on measurement results, the distribution of the temperature and humidity through the year and the change of the environment during conservation work were analyzed. Moreover, fluid analysis was conducted to understand the air movement inside the cave both in summer and in winter. The vertical distribution of temperature at the center of the cave was observed both in summer and in winter. The temperature change at the upper side was large and that at the lower side was little in summer, while that at the upper side was little and that at the lower side was large in winter. From this result, it is assumed that the outside air enters into the cave through the upper slit on the entrance door and goes out through the lower slit in summer. And this phenomenon was clarified by fluid analysis. The increase of 2 - 3 deg.C of temperature and that of 1.5 g/kg(DA) of humidity ratio were observed during conservation work. After conservation work, it took 6 - 12 hours until the temperature and humidity ratio retuned to the value before conservation work. The environmental change caused by conservation work was larger than that caused by natural ventilation. Since the relative humidity increased over 60% during conservation work, the number of workers and the duration of the work should be considered

调动学生学习兴趣提高解剖学教学效果

学习兴趣是指一个人对学习的一种积极的认识倾向与情绪状态,是一种带有趋向性的心理特征[1]。在教学实践中经常可以发现,尽管师资水平、教学方法、设备条件、学生的文化程度诸多因素基本