我国普通高等教育人力资源发展水平的统计分析

本文综合运用主成分分析和因子分析两种综合评价方法 ,对我国各地区高等教育人力资源的发展水平进行排序和分类 ,为规划和发展各地区的高等教育事业提供了一定的科学依据。两种综合评价方法的综合运用克服了单一评价方法的片面性 ,评价结果较为全面、客观     

水泥品质指标比对检验结果的评估及分析

本文采用稳健统计分析技术,对水泥品质指标比对检验质检机构的质检水平进行了能力验证,结合散点图和柱状图,综合评价了各实验室的检测能力。     

多维正态分布均值在序约束下的假设检验

在序限制下的统计推断是统计分析中的一个重要领域，保序回归理论在这个领域中起着关键性的作用。多维保序回归是一维保序回归的推广，本文给出了k=2,p=2时多维保序回归的求解方法。令Xij,j=1,2…，n是来自总体为二维正态分布N（μi，Λ)的样本，这是μi是未知的，Λ是已知的，i=1,2。令μ=（μ1,μ2)，-={（μ1,μ2)|μ1,μ∈R^2,}-0={(μ1,μ2)|μ1≤μ2,μ1，μ2∈R^2}。μ1≤μ2表示μ2-μ1的每一个分量为非负。本文也讨论了假设检验问题H0:μ∈-0,H1:μ∈-0=---0(H0是零假设）。     

Fitting models to correlated data III: A comparison between residual analysis and other methods

Applications of the χ² test, the F test, the Durbin-Watson d test, and the f (or Sign) test, to examples of correlated data treatment, show important drawbacks with the d test and (apparently) with the f test. An analytical approach based on residual analysis suggests an improvement in their use that leads to better results at lowest order; it also points out a distinction between goodness-of-fit tests, as the f test, and goodness-of-modeling tests, as the χ² and F tests. The residual analysis method is applied to the same examples; it looks faster, simpler, and often more accurate than the classical ones.     

用模态试验结果修改力学模型初探

利用试验模态分析结果,对有限元力学模型本身或其中某些参数进行修改是必要的和有工程意义的。这一“修改”既是数学上的优化问题又是工程设计问题。本文介绍自研制的“结构动力修改程序”,述及一般原理及框图,并给出一个悬臂梁实例。     

基于贝叶斯序贯方法的微波效应实验设计

提出了一种基于贝叶斯验后概率的序贯检验方法,建立了检验的判别准则,给出了判别准则临界值的计算方法。在给定截尾实验次数的条件下,提出了一种截尾方案,建立了截尾判断方法。将其用于解决验证效应物在微波作用下失效概率达到给定水平的微波效应实验设计问题,给出了相应的实验方案和所需样本量的估计。最后,通过实例对上述方法的应用过程进行了说明,并和现有方法进行了分析比较。     

Characterization and Spatial Matching of Laser Diode Beams

It is shown that the type of lateral waveguide of a laser diode cannot be determined uniquely based on just the measured magnitude of astigmatism. For a unique determination, the K-factor of Petermann, which characterizes the wavefront curvature at the laser output facet, must be measured as well. In order to determine the type of lateral waveguide, a setup for measuring astigmatic distances in the range 0–200 m with an error of ±2 m and a K-factor with an error of 20% was developed. Operational features of the setup were analyzed, and a technique that allows one to minimize the effect of beam ellipticity on the measurement results was found. Using the technique, the optimization of spatial matching of a laser diode with a ring interferometer of the butterfly type was accomplished. For transformation of the astigmatic elliptical beam into the axially symmetric mode of the interferometer, we have used an optical system that consists of two cylindrical and one spherical lenses. The algorithm for designing the matching system was developed, and the 85% injection of radiation of a AlGaAs laser diode into the principal mode of a ring interferometer was experimentally demonstrated.     

用干涉方法测量薄膜应力

基于基片弯曲法和牛顿环的基本原理,使用He-Ne激光器、扩束镜、凸透镜和带分光镜的移测显微镜,搭建了薄膜应力测量装置.采用直流溅射法制备了厚度为30~144 nm的银薄膜,衬底采用厚度为0.15 mm、直径为18 mm的圆形玻璃片.实验发现,薄膜厚度对银薄膜的内应力有显著的影响,在薄膜厚度很小时,随着薄膜厚度的增加,应力迅速增大,达到最大值后,随着厚度的继续增加,薄膜应力下降较快并趋于稳定值.     

Local Lead–Lag Relationships and Nonlinear Granger Causality: An Empirical Analysis

The Granger causality test is essential for detecting lead–lag relationships between time series. Traditionally, one uses a linear version of the test, essentially based on a linear time series regression, itself being based on autocorrelations and cross-correlations of the series. In the present paper, we employ a local Gaussian approach in an empirical investigation of lead–lag and causality relations. The study is carried out for monthly recorded financial indices for ten countries in Europe, North America, Asia and Australia. The local Gaussian approach makes it possible to examine lead–lag relations locally and separately in the tails and in the center of the return distributions of the series. It is shown that this results in a new and much more detailed picture of these relationships. Typically, the dependence is much stronger in the tails than in the center of the return distributions. It is shown that the ensuing nonlinear Granger causality tests may detect causality where traditional linear tests fail.     

Currents in a Quantum Nanoring Controlled by Non-Classical Electromagnetic Field

Quantum ring accommodating interacting spin-less fermions threaded by magnetic flux with a non-classical component added to a static, inducing persistent current, is considered. It is investigated how current flowing in the ring becomes affected by a state of non-classical flux and how Coulomb interaction between fermions influences entanglement of quantum ring and the driving field. In particular it is shown that in an absence of decoherence and under certain conditions fermion–fermion interaction is necessary for a ring–field entanglement to occur.