基于α-截集的企业知识管理能力模糊评价

在定义企业的知识管理能力后,给出了知识管理能力的评价指标.它们包括知识流程管理能力和知识管理基础能力.基于模糊理论建立了模糊成对比较矩阵.然后应用α-截集和几何平均方法进行了模糊权分析.基于模糊权分析,提出了企业的知识管理能力的模糊评价方法.该方法通过实例进行了验证.     

虚拟仪器设计中时间插补器的研究

本文首先简要介绍了虚拟仪器的定义和特点,然后根据积分电路原理和设计原则,设计了一种测试触发信号短时间间隔的新方法-时间插补器,通过对被测信号的控制,将被测时间转换,完成虚拟仪器中的部分设计任务.     

2000年NIM铯冷原子喷泉时间频率基准装置研究的进展

本文报导了中国计量科学研究院(MM)研制新一代"激光冷却铯原子喷泉"国家时间频率基准装置的进展实现了从磁光阱(MOT)过渡到光学黏胶(OM)装载-冷却铯(Cs)原子,利用飞行时间(TOF)法记录到信噪比优于40的原子云荧光信号;原子经后冷却达到(10～20)μK;用光学黏胶从铯蒸气直接获得了冷原子云.并给出了对实验的讨论.     

分子内电荷转移荧光探针法测定表面活性剂的临界胶束浓度

研究了分子内电荷转移荧光体4-二甲氨基查尔酮(DMAC)在表面活性剂水溶液中的荧光光谱。观察到随表面活性剂浓度增大,DMAC 的荧光光谱先红移然后蓝移,而荧光强度呈“S”型变化并于光谱位移方向转折处突跃。突跃处对应的表面活性剂浓度即为其临界胶束浓度(cmc)。结果表明由该法测定的 cmc 与已报道值符合,说明方法的可行性与准确性。用该法测定表面活性剂/β-环糊精混合体系的 cmc,表明β-环糊精的存在诱导了胶束的形成。     

F-doped carbon hollow nanospheres for efficient electrochemical oxygen reduction

Journal of Materials Science - Herein, a metal-free catalyst F-CHNS-900 has been prepared through a one-step pyrolysis of polytetrafluoroethylene and ZnCl2 at 900 °C. According to the...     

自动测试系统中状态参数的一种实时监测方法

对关系到测试资源和被测对象（UUT）安全的一些状态参数进行实时监控是自动测试系统开发中必须解决的一个关键问题，本文应用共享内存技术实现了对关键数据的实时监测，结果表明，该方法能有效地对关键数据实时监测，提高了测试系统的安全性。     

不同1、2-含量聚丁二烯及其硅氢加成产物的制备与透气性能的研究

合成了不同1、2-含量聚丁二烯及其硅氢加成产物,对聚丁二烯不饱和主链双键及乙烯基(外双键)的硅氢加成反应活性研究表明乙烯基的硅氢加成活性远高于主链双键。含氢硅烷的极性、反应介质的碱性都有利于硅氢加成反应的进行。硅氢加成产物的抗张强度较加成前提高,伸长率下降。在1、2-含量达到40%左右时成膜后膜对氧气透过率(Po_2)最大,选择分离系数(α+(N_2)~(O_2))最低。聚丁二烯三烷基硅氢加成产物成膜后膜对氧气的透过率均有较大改善,选择分离系数变化不大。     

A Network Traffic Classification Model Based on Metric Learning

Attacks on websites and network servers are among the most critical threats in network security. Network behavior identification is one of the most effective ways to identify malicious network intrusions. Analyzing abnormal network traffic patterns and traffic classification based on labeled network traffic data are among the most effective approaches for network behavior identification. Traditional methods for network traffic classification utilize algorithms such as Naive Bayes, Decision Tree and XGBoost. However, network traffic classification, which is required for network behavior identification, generally suffers from the problem of low accuracy even with the recently proposed deep learning models. To improve network traffic classification accuracy thus improving network intrusion detection rate, this paper proposes a new network traffic classification model, called ArcMargin, which incorporates metric learning into a convolutional neural network (CNN) to make the CNN model more discriminative. ArcMargin maps network traffic samples from the same category more closely while samples from different categories are mapped as far apart as possible. The metric learning regularization feature is called additive angular margin loss, and it is embedded in the object function of traditional CNN models. The proposed ArcMargin model is validated with three datasets and is compared with several other related algorithms. According to a set of classification indicators, the ArcMargin model is proofed to have better performances in both network traffic classification tasks and open-set tasks. Moreover, in open-set tasks, the ArcMargin model can cluster unknown data classes that do not exist in the previous training dataset.     

非枝晶AlSi7 Mg合金半固态触变成形研究

研究了AlSi7Mg合金的触变形成,结果表明：在电磁搅拌下,制备出半固态AlSi7Mg合金连铸坯料,合适的连铸速度为1．5－3mm/s,在变功率电感应加热下,半固态AlSi7Mg合金坯料的温度场可以达到很均匀,合适的加热温度为580－590℃,在模具温度100－300℃和比压15－25MPa条件下,触变锻造出汽车制动总泵体和比例阀毛坯。     

两端简支圆柱体的轴对称振动

本文用三维弹性动力学理论研究圆柱体在两端简支约束下的轴对称自由振动问题。给出位移振型和应力振型的解析表达式，求得固有频率的精确解。研究结果表明：在圆柱体的径向还存在着不同的半波数的位移振型，这种性质在初等理论中是无法反映的