纳秒级脉冲激光自动跟踪积分式测量方法

介绍了一种纳秒级脉冲激光光斑能量分布测量电路的设计方法,采用自动跟踪积分方式,根据预测先将脉冲光电流积分并保存,然后用速度较低的A/D芯片进行A/D转换,该方法避免了采用高速A/D芯片,且可以获得较高的采样分辨率,特别是在需要采集的通道数较多时具有明显优势。     

Towards the automatic analysis of NMR spectra: part 7. Assignment of 1H by employing both 1H and 1H/13C correlation spectra

A reliable method of automatically assigning one-dimensional proton spectra is described. The method relies on the alignment of the proton spectrum with an associated heteronuclear single-quantum coherence (HSQC) spectrum, transferring the stoichiometry and couplings to the HSQC. The HSQC spectrum is then assigned using a linear assignment procedure in which a fitness function incorporating (1)H chemical shifts, (1)H couplings and (13)C shifts are employed. The method uniquely employs a sequential procedure in which only correlations of like stoichiometry are assigned at the same time.     

基于信息熵的汽车故障诊断复杂性评价

由于大量高新技术在现代汽车中的综合运用,仅利用设备维修复杂系数作为制定设备维修工时定额的方法已不能体现现代汽车修理工作量差异,而现代汽车维修工时定额更应考虑该故障诊断复杂性差异对维修工时的影响,所以对汽车故障诊断复杂性进行评价很有必要.应用信息熵的方法探讨了汽车故障诊断复杂性的评价方法,首先介绍了信息熵评价复杂性的相关理论,给出了汽车故障诊断整体复杂性评价指标以及复杂性熵尺度评价模型,最后以发动机过热为实例,分析了故障判断层次结构,利用信息熵方法计算出故障诊断的复杂性值.实证结果表明评价方法和模型具有一定的实用性和可行性,可实现对现有的汽车维修工时定额的修正.     

A nonlinear principal component analysis to study archeometric data

Statistical techniques, when applied to data obtained by chemical investigations on ancient artworks, are usually expected to recognize groups of objects to classify the archeological finds, to attribute the provenance of items compared with earlier investigated ones, or to determine whether an archaelogical attribution is possible or not. The statistical technique most frequently used in archeometry is the principal component analysis (PCA), because of its simplicity in theory and implementation. However, the application of PCA to archeometric data showed severe limitations because of its linear feature. Indeed, PCA is inadequate to classify data whose behavior describe a curve or a curved subspace of the original data space. As a consequence of it, an amount of information is lost because the multi‐dimensional data space is compressed into a lower‐dimensional subspace including principal components. The aim of this work is then to test a novel statistical technique for archeometry. We propose a nonlinear PCA method to extract maximum chemical information by plotting data on the smallest number of principal components and to answer archeological questions. The higher accuracy and effectiveness of nonlinear PCA approach with respect to standard PCA for the analysis of archeometric data are shown through the study of Apulian red figured pottery (fifth–fourth century BC) coming from some of the most relevant archeological sites of ancient Apulia (Monte Sannace (Gioia del Colle), Egnatia (Fasano), Canosa, Altamura, Conversano, and Arpi(Foggia)). Copyright © 2016 John Wiley & Sons, Ltd.     

Self-Organization,Entropy Generation Rate,and Boundary Defects: A Control Volume Approach

Self-organization that leads to the discontinuous emergence of optimized new patterns is related to entropy generation and the export of entropy. Compared to the original pattern that the new, self-organized pattern replaces, the new features could involve an abrupt change in the pattern-volume. There is no clear principle of pathway selection for self-organization that is known for triggering a particular new self-organization pattern. The new pattern displays different types of boundary-defects necessary for stabilizing the new order. Boundary-defects can contain high entropy regions of concentrated chemical species. On the other hand, the reorganization (or refinement) of an established pattern is a more kinetically tractable process, where the entropy generation rate varies continuously with the imposed variables that enable and sustain the pattern features. The maximum entropy production rate (MEPR) principle is one possibility that may have predictive capability for self-organization. The scale of shapes that form or evolve during self-organization and reorganization are influenced by the export of specific defects from the control volume of study. The control volume (CV) approach must include the texture patterns to be located inside the CV for the MEPR analysis to be applicable. These hypotheses were examined for patterns that are well-characterized for solidification and wear processes. We tested the governing equations for bifurcations (the onset of new patterns) and for reorganization (the fine tuning of existing patterns) with published experimental data, across the range of solidification morphologies and nonequilibrium phases, for metallic glass and featureless crystalline solids. The self-assembling features of surface-texture patterns for friction and wear conditions were also modeled with the entropy generation (MEPR) principle, including defect production (wear debris). We found that surface texture and entropy generation in the control volume could be predictive for self-organization. The main results of this study provide support to the hypothesis that self-organized patterns are a consequence of the maximum entropy production rate per volume principle. Patterns at any scale optimize a certain outcome and have utility. We discuss some similarities between the self-organization behavior of both inanimate and living systems, with ideas regarding the optimizing features of self-organized pattern features that impact functionality, beauty, and consciousness.     

基于运动控制技术的编码器自动检测系统

为了改进编码器误差检测方法,提高检测效率,基于对光电轴角编码器误差检测现状的分析,设计了一种编码器误差自动检测系统。介绍了自动检测系统的工作原理,系统的硬件设计和软件设计。利用运动和全闭环控制技术,以24位高精度增量式光电轴角编码器为反馈元件,该自动检测系统可自动完成对编码器测试点的定位、数据获取和误差数据分析,定位精度为2″,可以检测18位以下各类光电轴角编码器的误差,检测效率是标准检测装置的6倍。该实验结果验证了方案的可行性。     

Automated compound verification using 2D-NMR HSQC data in an open-access environment

Since the introduction of NMR prediction software, medicinal chemists have imagined submitting their compounds to corporate compound registration systems that would ultimately display a simplified pass/fail result. We initially implemented such a system based on HPLC and liquid chromatography mass spectrometry (LCMS) data that is embedded within our industry standard sample submission and registration process. By using gradient-heteronuclear single quantum coherence (HSQC) experiments, we have extended this concept to NMR data through a comparison of experimentally acquired data against predicted (1)H and (13)C NMR data. Integration of our compound registration system with our analytical instruments now provides our chemists unattended and automated NMR verification for collections of submitted compounds. The benefits achieved from automated processing and interpretation of results produced enhanced confidence in our compound library and released the chemists from the tedium of manipulating large amounts of data. This allows scientists to focus more of their attention to the drug discovery process.     

运筹学在汽车零部件入厂物流中的应用

汽车物流包括供应物流(零部件入厂物流)、生产物流、销售物流和回收物流,其中零部件入厂物流因其技术性强、复杂度高,被公认为汽车物流系统良性运作的关键环节.在分析汽车零部件入厂物流的基础上,研究运筹学在汽车零部件入厂物流中的应用, 构建数学模型,并用贪婪算法求解.