Robust sparse principal component analysis

The model for improving the robustness of sparse principal component analysis（PCA） is proposed in this paper. Instead of the l2-norm variance utilized in the conventional sparse PCA model,the proposed model maximizes the l1-norm variance,which is less sensitive to noise and outlier. To ensure sparsity,lp-norm（0 p 1） constraint,which is more general and effective than l1-norm,is considered. A simple yet efficient algorithm is developed against the proposed model. The complexity of the algorithm approximately linearly increases with both of the size and the dimensionality of the given data,which is comparable to or better than the current sparse PCA methods. The proposed algorithm is also proved to converge to a reasonable local optimum of the model. The efficiency and robustness of the algorithm is verified by a series of experiments on both synthetic and digit number image data.     

高抗冲聚苯乙烯的阻燃研究

利用锥形量热仪(CONE)研究了阻燃高抗冲聚苯乙烯(HIPS)的燃烧性能,同时也采用垂直燃烧、氧指数等方法进行了对比测试。含十溴二苯乙烷的试样不仅保持了原有的物理机械性能,而且阻燃效果明显。相对于使用十溴二苯醚阻燃的HIPS,十溴二苯乙烷的使用不会产生多溴代二问题,产品符合一定的环保要求。     

水滴形歧管的结构分析

本文就衣架式模头水滴形歧管的结构设计，根据聚合物加工的流变理论，结合生产实际对水滴形截面的歧管流道分配系统进行分析，使得所设计的挤塑模在尽可能高的流速下，生产出符合尺寸及形状公差的均质片材。     

高校创新教育中存在的问题及对策

创新教育是一个不断改革发展的过程,更是一个需要在实践中不断探索的过程。开展教育创新,除了思想认识、教育模式、课程内容和教育手段等问题以外,还有教师方面的问题和教学管理方面的问题。创造适合创新教育的环境、突出以人为本的原则、具有良好的政策导向以及创造一个宽松、自由的创新制度、构建符合高校自身实际的创新性课程体系,是高等学校开展创新教育的基本保障。     

基于人体骨骼关键点的吸烟行为检测算法

针对公共场所的监控视频中烟头目标较小并且吸烟产生的烟雾易发散,仅依靠目标检测算法检测烟头或者烟雾来判定吸烟行为存在较大难度的问题,考虑到利用骨骼关键点来进行姿态估计的算法越来越成熟,提出一种利用人体骨骼关键点和吸烟行为之间的关系来进行吸烟行为检测的算法。该算法首先利用AlphaPose和RetinaFace分别检测出人体骨骼关键点和脸部关键点信息,根据手腕到两嘴角中点和手腕到同侧眼睛的距离之比,提出一种计算人体的吸烟动作比例（SAR）是否属于吸烟动作黄金比例（GRSA）的方法以区分吸烟与非吸烟行为;再利用YOLOv4检测视频中是否存在烟头;最后结合GRSA判定和YOLOv4的结果来确定视频中存在吸烟行为的可能性高低,作出是否有吸烟行为的判定。经过笔者录制的数据集测试,结果表明所提算法可以准确检测到吸烟行为,准确率达到92%。     

基于主题教学模式视阈下中餐烹饪教学设计研究 ——以肉类菜肴制作为例

文章指出了传统教学模式下中餐烹饪教学所存在的问题,以及主题教学模式应用于中餐烹饪教学所带来的改变,因势利导阐述了基于主题教学模式理念下中餐烹饪肉类菜肴制作的具体教学设计案例,并反思了此教学设计案例的成功与不足,最后分析了主题教学模式理念下中餐烹饪教学实施过程中面临的挑战,以期为中餐烹饪教学设计提供参考与借鉴.     

车辆荷载作用下贝雷梁钢便桥动态响应数值仿真分析

以现代抢险救灾常用的贝雷梁钢便桥作为研究对象,采用ANSYS对其建立空间整体有限元模型,运用瞬态分析方法,模拟车辆过桥的整个过程,分析贝雷梁钢便桥的动态响应.结果表明:双排贝雷梁不均匀承担荷载,内侧贝雷梁相对较大,尤其在中轴和后轴荷载作用时,内外贝雷梁竖向位移差异最大;双排贝雷梁侧向位移几乎相同,且在中轴和后轴荷载作用时最大;主要以侧向和竖向振动为主,且不可忽略侧向振动响应,轴向振动响应较小可忽略不计.     

承德地方企业与高校合作公共政策

我国70%左右的科技人员集中在高校、科研院所。高等学校具有全国最强的创新资源和优势。承德市经济基础薄弱、技术水平较低,但是具有丰富的自然资源,特别是山林、水和旅游资源丰富,随着高速公路网和高铁的建设,已经成为京津冀和东北、内蒙的交通枢纽。如果能够科学合理地选择合作方式,建立基于市场的长期有效的激励机制就能够把这两种优势有效地结合起来,产生巨大的发展动力,有力地促进创新型城市的发展。     

Non-Fourier heat conduction in a thin gold film heated by an ultra-fast-laser

Based on the dual-phase-lagging(DPL)heat conduction model,the Cattaneo-Vernotte(CV)model and the improved CV model we investigate the one-dimensional heat conduction in gold films with nano-scale thickness exposed to an ultra-fast laser heating.The influence of system parameters on the temperature field is explored.We find that for all the non-Fourier heat conduction models considered in this work,a larger Knudsen number normally leads to a higher temperature.For the DPL model,the large ratio of the phase lag of temperature gradient to the phase lag of heat flux reduces the maximum temperature and shortens the time for the system to reach its steady state.The CV model and the improved CV model lead to the similar thermal wave behavior of the temperature field,but the thermal wave speeds for these two models are different,especially for large Knudsen numbers.When the phase lag of temperature gradient is smaller,the difference between the DPL model and the improved CV model is not significant,but for the large phase lag of temperature gradient the difference becomes quite significant,especially for the large Knudsen number.In addition,the effect of the surface accommodation coefficient,which is a parameter in the slip boundary condition,on the temperature field of the gold film heated by ultra-fast laser pulses is investigated based on the DPL model.