与教育国际化接轨,制作网络视频公课简

针对网络视频公开课（OCW）出现近十多年来的经验与现状,华东理工大学在原先国家精品课程视频公开的基础上,另行启动了包括全英文课程在内的视频公开课制作工作。运行工作针对国内教学的实际情况,探索了一些实际操作的经验,以供国内相关高校相互交流。     

基于冗余技术对防爆低压真空馈电开关中智能保护器的改进设计与矿井供电安全

通过对矿用防爆智能化真空馈电开关单片机保护器所存在缺陷的分析,提出利用冗余技术提高其短路保护性能的可靠性,从而提高矿井供电系统的安全性.     

多点驱动带式输送机功率平衡机制研究

针对多点驱动带式输送机功率不平衡降低输送效率及生产寿命问题,对多电机间的协调控制进行研究。对传统偏差耦合多电机协调控制结构进行了改进,增加了基于转速功率控制的同步误差补偿器,通过求取所有电机的平均转速和单台电机的转速差,利用PI控制器,同时结合每台电机的系统转速跟踪误差,反馈补偿到每台电机的控制回路进行多电机协调控制。仿真结果表明,系统可以在负载变化扰动的情况下有效降低各电机的同步误差,特别是对系统刚启动时负载不均衡导致的电机功率不平衡问题,改进结构可以有效实现多电机间的功率平衡分配。     

Highly efficient synthesis of(R)-1,3-butanediol via anti-Prelog reduction of 4-hydroxy-2-butanone with absolute stereoselectivity by a newly isolated Pichia kudriavzevii

(R)-1,3-butanediol is an important pharmaceutical intermediate, and the synthesis of(R)-1,3-butanediol using green biological methods has recently been of interest for industrial application. Here, a novel strain QC-1 that efficiently transforms 4-hydroxy-2-butanone to(R)-1,3-butanediol was isolated from soil samples. Based on morphological, physiological, and biochemical tests and 5.8 S-internal transcribed spacer sequencing, the strain was identified as Pichia kudriavzevii QC-1. The reaction conditions were optimized to 35 ℃, pH 8.0, rotation speed 200 rpm, and 6:5 mass ratio of glucose to 4-hydroxy-2-butanone. Evaluation of the effects of 4-hydroxy-2-butanone concentrations on yield and cell survival rate showed that 85.60 g·L~(-1) product accumulated, with an enantiomeric excess of more than 99%, when 30 g·L~(-1)4-hydroxy-2-butanone was added at 0, 10, and 30 h in a 3-L bioreactor. Thus, strain QC-1 showed excellent catalytic activity and stereoselectivity for the synthesis of(R)-1,3-butanediol from 4-hydroxy-2-butanone.     

网络功能虚拟化下服务功能链的资源管理研究综述

伴随着云计算,软件定义网络和网络功能虚拟化等网络新技术的出现,未来网络运维向着虚拟化、智能化的方向不断迈进.网络功能虚拟化提供了一种服务节点虚拟化的方法,它采用通用服务器替代传统网络中的专用中间件,可以大大降低网络运营商的建设和运营成本,提升网络管理的灵活性和可扩展性.由于网络端到端服务通常需要不同的服务功能,采用虚拟...     

An improved fitting method for subgroup parameters based on the heterogeneous cells

An accurate subgroup parameters fitting method, where background cross sections obtained based on heterogeneous cells are used to fit the subgroup level and subgroup weight, is proposed in this paper. Due to the dependence of background cross section on the subgroup level, the calculation of the subgroup parameters is a nonlinear problem, which causes the iteration between fitting subgroup parameters and updating background cross sections. The cubic spline interpolation method is used to update the background cross sections to avoid frequently solving fixed source equations. In the fitting process, the negative subgroup parameters are often obtained, and the accuracy of the subgroup parameters is very sensitive to the iterative initial values of subgroup levels. To avoid these problems, additional constraints ensuring positive subgroup parameters and guaranteeing numerical stability are added to the optimization function. Penalty function method is used to convert the optimization problem with constraints into the one without constraints, making the problem easy to be solved. The proposed method is tested against the problems of pin cell, pressurized water reactor assemblies and plate-type assembly. The numerical results show that the self-shielded cross sections calculated by the proposed method agree well with those by Monte Carlo code.     

共混法制备酸性可染聚丙烯腈纤维

用含有碱性基团的丙烯酸氨基酯(TAM)与丙烯腈(AN)单体共聚,其共聚物与聚丙烯腈(PAN)共混,经湿法纺丝制备酸性染料可染PAN共混纤维。结果表明,AN／TAM共聚物与PAN有良好的相容性。随着TAM含量的增加,PAN共混纤维结晶度下降,力学性能下降。纤维中TAM质量分数5％较好,PAN共混纤维酸性染料上染率大于80％。     

齿轮接触疲劳寿命、强度及应力最佳分布类型的确定

通过对60对合金钢调质齿轮接触疲劳寿命试验数据的分析处理,找出了齿轮的3种随机变量(寿命,强度,应力)最佳分布类型和可能分布类型,从而为齿轮的高可靠性设计提供了基础和依据。     

林口县学校周边“小饭桌”食品卫生监督管理成效初探

为加强和规范学校周边"小饭桌"的经营行为,提高卫生监督管理水平,确保学生的身体健康,对林口县学校周边"小饭桌"实施了一系列监督管理措施,取得了良好的成效,并将在日常的卫生监督管理中引入HACCP系统原理,紧抓关键控制点,以确保广大学生的饮食安全。     

超声辅助同时提取迷迭香鼠尾草酸和迷迭香酸

以迷迭香干叶为原料,采用超声辅助的方法从迷迭香中提取迷迭香酸、鼠尾草酸等有效成分,考察了超声提取时间、乙醇体积分数、料液比和超声功率等因素对提取工艺的影响,并通过响应面法进行工艺优化,得到了提取过程优化的工艺条件:乙醇体积分数72.29%、料液比1∶10.05、超声时间51.27 min、超声功率200.55W。拟合得到的模型较好的符合实际。