面向主题的Web数据采集及信息整合系统的设计与实现

提出了一个基于ASP技术的可靠的动态交互数据采集及信息整合系统,介绍了它的设计思想和工作原理,详细阐述了整个系统关键部分的实现过程。实验结果表明,该数据采集系统,具有很好的安全性、交互性,并具有较好的实践意义。     

基于轻量型Web服务器的嵌入式设备的Web服务编程设计

由于嵌入式设备存储空间有限,所以在嵌入式设备中应该选择小型Web服务器,如thttpd、lighttpd等.介绍了对嵌入式设备使用Web服务器进行连网管理时,Web服务(如远程固件更新)的编程设计,并给出一个设计实例.     

泥页岩稳定性评价中人工模拟岩样的制备

改进了泥页岩稳定指数(SSI)评价实验方法中人工模拟实验岩样的制备方法。使用B28井岩粉制备岩样,优选SSI实验模拟岩样制备条件为:10.5 MPa下压制浆液,得到含水量14.03%的岩样模拟上部高含水量地层;10.5 MPa下压制风干岩粉,得到含水量1.91%的岩样模拟深部低含水量地层。优选SSI实验条件为:在65℃试液中浸泡8 h后,测定岩样的SSI值。扫描电镜(SEM)微结构分析表明,两种方法制备的岩样与实际泥页岩的微观孔隙尺度相近,高含水量模拟岩样的含水量与浅部实际地层泥页岩含水量(12%14%)相近,低含水量模拟岩样的含水量与深部实际地层泥页岩含水量(2%3%)相近。改进的SSI评价方法相对误差为2.91%,平行性较好,可有效评价防塌剂和防塌体系对泥岩地层的防塌效果及作用机理。     

基于特征值分解的随机子空间算法研究

针对基于数据驱动的随机子空间法计算效率低下的问题,提出一种基于特征值分解的随机子空间算法,该方法通过对ＣＨ矩阵的特征值分解得到扩展可观测矩阵Ｔｍｉ,进而识别出系统模态参数。相比于传统算法,该算法免去了对Ｈａｎｋｌ矩阵的ＱＲ分解及投影矩阵的ＳＶＤ运算,从而大大节省了内存和计算时间。通过一个７自由度的数值仿真和重庆朝天门大桥模型的实例分析证明该方法在保持计算精度的情况下大幅度地提升了计算效率。     

Effects of deletion in the flexible loop of the protease inhibitor SSI (Streptomyces subtilisin inhibitor) on interactions with proteases

The Streptomyces subtilisin inhibitor (SSI) is a proteinaceousprotease inhibitor which inhibits serine proteases by forminga stable Michaelis complex. The flexible loop region (Thr64–Val69)is a very flexible region in an SSI molecule and its importancein interactions with proteases has been suggested, since conformationalchange of this loop was found to occur for the smooth bindingof SSI with various proteases. In this study, mutated SSIs lackingone or two residues in this region were generated and the effectsof deletions on the interaction with proteases were investigated.Deletion was introduced into mutated SSI(Lys73) and SSI(Gly70Lys73)both known to be trypsin inhibitors, to examine the effectsof deletion on interactions with subtilisin BPN' or trypsin.The deletion of one residue (Gly66) caused increased inhibitoryactivity toward trypsin, indicating the protruding flexibleloop hinders binding with trypsin. Reduction of such hindranceby one-residue shortening in this loop is shown to be effectivefor the interaction of SSI(Lys73) with trypsin. In contrast,one-residue shortening had virtually no effect on inhibitiontoward subtilisin BPN'. Differences in the subsite structuresof these proteases may have been the reason for this contrast.The deletion of two residues (Thr64 and Gly66) in this regionconverted SSI into a temporary inhibitor. Structural analysisof the degradation intermediate showed that the peptide bondat the reactive site of doubly deleted SSI was cleaved by subtilisinBPN' after its binding with protease. Thus, the irreversibilityof the cleaved peptide bond at the reactive site of mutatedSSI in the complex with protease may possibly be the cause forits temporary inhibition. Irregular conformation around thereactive site caused by the deletion of two residues in theflexible loop would convert SSI into a temporary inhibitor.Thus, moderate flexibility in the flexible loop region may possiblybe a structural requirement for SSI to function.     

Accelerated Reliability Demonstration Testing Design Based on Reliability Allocation of Environmental Stresses

The traditional reliability demonstration testing based on statistical method requires a large number of samples and long testing time, failing to satisfy the demand for short cycle and low cost. This paper proposes a new accelerated approach for determining reliability target of each environment stress, accelerated test profile, and comprehensive acceleration factor for multi‐failure mode product to conduct assembly level accelerated demonstration testing under multiple stresses and levels. By decomposing the product from four levels, namely function, structure, mechanism, and stress, the products' weaknesses can be identified. The main failure modes and sensitive environmental stresses are determined based on environmental profile and FMMEA. In this design, the reliability is apportioned to each actual environmental stress by AHP. And the SSI model is used to establish accelerated stress profile. The overall acceleration factor can be derived from the model of assembly level accelerated testing. Combined with a statistical plan, the accelerated reliability demonstration testing plan and test profile is built. A case example is presented to illustrate the effectiveness of the proposed approach. Copyright © 2017 John Wiley & Sons, Ltd.     

基于SSI-MSVM的调相机轴承故障诊断方法

随着新能源的并网与特高压直流输电的发展,电网对无功调节的要求也逐步提高,因此大型调相机再次被投入使用。为了便于对调相机轴承进行故障诊断,提出了一种基于随机子空间识别(SSI)和多核支持向量机(MSVM)的故障诊断方法。在调相机轴承外侧表面不同的位置利用振动传感器采集振动信号,利用随机子空间模型进行特征提取,再根据高斯支持向量机和多核学习方法构造MSVM,然后将提取出的特征数据输入MSVM进行故障诊断。试验结果证明,基于SSI-MSVM的故障诊断方法能够适用于调相机轴承,且可以成功对故障进行辨识。     

软基上土-结构相互作用体系的一个广义简化动力计算模型

在前期试验研究基础上 ,提出了软基SSI体系的一个广义简化动力计算模型 ,得出了模型参数的反演算法 ,同时以试验SSI体系为例 ,给出了简化计算模型下的物理参数结果 ,并讨论了其合理性。     

基于ARM的双电机控制实验平台设计

以LM3S9896和AD5752为核心,设计了控制卡,解决了主机和从机在帧长度不同的时候进行同步串行通信的问题,并结合安川伺服电机,搭建起双电机控制算法实验平台。实验表明,该实验平台能够用于控制算法测试验证。同时,该控制卡也适用于智能分布式控制系统的组建。     

一种C8051F单片机读取SSI信号的设计

目前许多角度编码器将采集后的角度数字量通过SSI接口输出,供处理器读取。基于C8051F单片机内部所带PCA0可编程计数器阵列外设,设计一种适用于读取SSI接口信号的接口。通过实际应用运行,证明该设计方案稳定可靠,并且配置灵活,完全符合SSI接口协议标准。