Improvement of quantitative analysis of molybdenum element using PLS-based approaches for laser-induced breakdown spectroscopy in various pressure environments

An experimental setup has been designed and realized in order to optimize the characteristics of laser-induced breakdown spectroscopy system working in various pressure environments. An approach combined the normalization methods with the partial least squares(PLS) method are developed for quantitative analysis of molybdenum(Mo) element in the multi-component alloy,which is the first wall material in the Experimental Advanced Superconducting Tokamak. In this study, the different spectral normalization methods(total spectral area normalization,background normalization, and reference line normalization) are investigated for reducing the uncertainty and improving the accuracy of spectral measurement. The results indicates that the approach of PLS based on inter-element interference is significantly better than the conventional PLS methods as well as the univariate linear methods in the various pressure for molybdenum element analysis.     

3.5%Ni钢最佳强韧性的正交试验

为使3.5%Ni钢热处理后得到优良的强韧性,在试验室对3.5%Ni钢的正火加回火热处理工艺进行了正交试验设计,采用L9(34)的三水平四因素试验方案进行了热处理试验。试验结果表明,正火温度和回火温度是影响强度的主要因素,其可信度在99%以上,正火温度和回火时间是影响韧性的主要因素,其可信度分别为97.5%和90%。根据方差分析确定了3.5%Ni钢的最佳热处理工艺。     

液化石油气杂质含量的气相色谱法测定

通过恒温水浴完全气化样品,建立了用毛细管气相色谱法测定液化石油气中二甲醚、甲醇及甲缩醛含量的方法。采用PLOT/Q(30 m×0.53 mm×40μm)毛细管柱、热导池检测器,以面积校正归一化法计算杂质含量。结果表明:该方法操作简单,实用性强,重复性好,可以用于液化石油气中杂质含量的快速分析。     

浅谈规范农药助剂的使用

正确使用农药助剂的必要性体现在农药助剂对农药制剂技术标准的影响和对药效的影响。当前农药助剂使用中存在不规范现象较为普遍,本文对规范农药助剂的使用,特别是农药表面活性剂的规范使用进行探讨。     

基于贝叶斯信念网络的多案例库检索方法

为了克服在基于案例推理中单一案例库检索的局限性,提出了基于贝叶斯信念网络的多案例库检索方法.该方法仅要求用户采用关键词对目标案例进行描述,通过贝叶斯信念网络计算关键词与各案例库的特征属性的匹配概率,以获得适应各案例库的完整的目标案例描述,然后对相应的案例库进行案例检索;将从多案例库中检索到的案例通过相似度线性归一处理后,结合目标案例描述的匹配概率获得与目标案例的最终相似度,统一排序后返回检索结果.最后通过航空企业的实际应用与性能分析进一步验证了多案例库检索方法的有效性.     

词频规范化改善信息检索查准率

研究了词频规范化，通过实例指出并分析了极大规范化词频、对数词频和平均词频这3种现有的词频规范化方法的不足，在理论上探究了影响词频规范化的因素。通过引入新参数的方法对词频规范化予以改进，以试错法给出了3种可能的词频规范化形式，并经数学推导，最终给出了改进的词频规范化方法，并通过实验验证了改进的词频规范化形式的有效性。     

DETECTION OF SCANS

Abstract

Most automatic parallelizes are based on the detection of independent operations. Dependence analysis is mainly a syntactical process, in which the actual data transformations are ignored. There is another source of parallelism, which relies on semantical information, namely the detection of reductions and scans. Scans and reductions are quite frequent in scientific codes and are implemented efficiently on most parallel computers. We present here a new Scan detector which is based on the normalization of systems of recurrence equations. This allows the detection of scans in loops nests of arbitrary depth and on multi-dimensional arrays, and gives a uniform treatment for scalar reductions, array reductions, and arrays of reductions.     

模糊数学在机械设计综合评判中的应用

以模糊数学为理论基础,通过对高压大流量乳化液泵结构方案的分析,建立了机械产品结构方案的模糊综合评判模型,从而将人们头脑中的模糊概念应用于计算机辅助设计,为机械产品设计提供了一种较为客观的选优方式。     

Score normalization in multimodal biometric systems

Multimodal biometric systems consolidate the evidence presented by multiple biometric sources and typically provide better recognition performance compared to systems based on a single biometric modality. Although information fusion in a multimodal system can be performed at various levels, integration at the matching score level is the most common approach due to the ease in accessing and combining the scores generated by different matchers. Since the matching scores output by the various modalities are heterogeneous, score normalization is needed to transform these scores into a common domain, prior to combining them. In this paper, we have studied the performance of different normalization techniques and fusion rules in the context of a multimodal biometric system based on the face, fingerprint and hand-geometry traits of a user. Experiments conducted on a database of 100 users indicate that the application of min–max, z-score, and tanh normalization schemes followed by a simple sum of scores fusion method results in better recognition performance compared to other methods. However, experiments also reveal that the min–max and z-score normalization techniques are sensitive to outliers in the data, highlighting the need for a robust and efficient normalization procedure like the tanh normalization. It was also observed that multimodal systems utilizing user-specific weights perform better compared to systems that assign the same set of weights to the multiple biometric traits of all users.     

A face recognition system based on automatically determined facial fiducial points

In this paper, a completely automatic face recognition system is presented. The method works on color images: after having localized the face and the facial features, it determines 24 facial fiducial points, and characterizes them applying a bank of Gabor filters which extract the peculiar texture around them (jets). Recognition is realized measuring the similarity between the different jets. The system is inspired by the elastic bunch graph method, while it does no assumption on the scale, pose, and the background. Comparison with standard algorithms is presented and discussed.