基于MF-R和AWS密钥管理机制的物联网健康监测大数据分析系统

带有传感器的可穿戴式医疗设备不断生成大量数据，由于数据的复杂性，难以通过处理和分析大数据来找到有价值的决策信息。为了解决这个问题，提出了一种新的物联网体系结构，用于存储和处理医疗应用的可扩展传感器数据（大数据）。所提出的架构主要由两个子架构组成：Meta Fog重定向（MF-R）架构和AWS密钥管理机制。MF-R架构使用Apache Pig和Apache HBase等大数据技术来收集和存储不同传感器设备生成的传感器数据，并利用卡尔曼滤波消除噪声。AWS密钥管理机制使用密钥管理方案，目的是保护云中的数据，防止未经授权的访问。当数据存储在云中时，所提出的系统能够使用随机梯度下降算法和逻辑回归来开发心脏病的预测模型。仿真实验表明，和其他几种算法相比，提出的算法具有更小的误差，且在吞吐量、准确度等方面具有一定的优越性。     

Research and Development of a Network—Based Intelligent Maintenance Information System

A maintenance information system is an important part of equipment management.An intelli-gent maintenance information system(IMIS)is a synthesis of network technology,information technology and intelligent technology.The IMIS in used to finish flexible maintenance decision-making and fast main-tenance planning,which helps enterprises to effectively reduce maintenance cost and increase working effi-ciency.Because the IMIS integrates advanced technologies,its performance is better than a traditional one.The difference between an IMIS and a traditional maintenance information system,and the functions,struc-ture,important realizations,and application of an IMIS are discussed in this paper.     

Grain Boundary Sliding in Fatigue of Pure Aluminum

The distributions of plastic strain near grain boundaries induced by fatigue loading were investigatedby the fiducial grid method in pure aluminum specimens, and the resulted grain boundary sliding(GBS) was systematically analysed. The results show that the strain field near a grain boundary isnonuniform. GBS is restricted by the junction of grain boundaries and causes discontinuities of bothdisplacement and strain. A peak value of shear strain was created in short-range area across the grainboundary. GBS plays an important role in cyclic softening and secondary hardening. The control fac-tor of GBS is the relative orientation between two grains and the macro orientation of the grainboundary rather than the ∑ value of the boundary.     

工艺因素对金属封装外引线弯曲疲劳的影响

考察了金属封装外壳制造工艺对外引线弯曲疲劳的影响,发现电镀镍是导致外引线弯曲次数明显减少的最主要工艺步骤,且随镀镍层厚度的增加,弯曲次数减少。此外还讨论了外引线的氢含量和晶粒度对引线抗疲劳能力的影响。     

入侵检测及网络层安全的研究

随着计算机网络的迅速发展，网络安全问题正变得日益重要。文章介绍了计算机网络系统IP层安全概况和入侵者对IP层常采用的入侵手段，以及为防止这种入侵所采取的措施。     

未结盟大学的联盟

通过梳理管理学界对战略联盟的定义，发现价值链的鸸释同样适用于大学问的战略联盟。通过对已有的大学战略联盟的分析，提出了名校联盟与非名校联盟间的若干差异，最后提出了我国大学联盟战略的若干建议。     

立体车库二次调节提升系统的节能特性与转速控制

介绍了立体车库二次调节静液传动提升系统的工作原理、特点和节能特性，并进行了转速控制的试验研究，得出了应用二次调节技术能够回收和重新利用系统的制动动能和重力势能，减小系统装机容量。     

FE Simulation for Internal Inversion of Aluminium Alloy Tube

1 Introduction A double-walled invertube is difficult to fabricate other than applying inversion process. Such kind of invertube can be used as impact energy absorbing element in transport vehicles, like aircrafts and automobiles. Reddy T Y[1] did the analysis of Internal inversion and calculated the inversion load. Reid[2] et al. examined nosing and internal inversion of cold drawn steel tube by the finite element package ABAQUS. Recently, Rosa P A[3] et al. investigated Internal invers…     

膜-粉末炭反应器净化微污染源水

采用膜-粉末炭反应器处理微污染源水的试验结果表明,该工艺对水中的有机物具有较好的净化效果,在水温《10℃的条件下,处理可生化性很低的三家店水库水时对CODMn的去除率仍保持在65%左右;工艺对CODMn、UV254、UV410的去除效果依次增强.