翼片加载螺旋线慢波系统的特性分析

通过切比雪夫多项式展开螺旋带上的面电流,用真空层模拟螺旋带的厚度、均匀分层介质等效介质夹持杆、用无限多个无限薄的翼片等效实际翼片,得到了色散方程、平均耦合阻抗和衰减常数的表达式。与实验数据相比,结果接近实验值,该文提出的方法对实际螺旋线慢波系统的设计具有重要的指导意义。     

稀土氨基酸在混合溶剂中的配位常数测定及热力学常数计算

用ｐＨ法测定了镧和天门冬氨酸在水—二甲基亚砜、钕和甘氨酸在水—二氧六环混合溶剂中的配位常数．测定精度为±０．０１ｐＨ单位．通过加入一定量硝酸钾溶液维持溶液的离子强度（０．１０ｍｏｌ／Ｌ）．测定时采用氮气氛保护并保持温度变化不超过±０．２Ｋ．利用配位常数计算了这些配合物在混合溶液中的△Ｇ°、△Ｈ°和△Ｓ°．     

On maxima of chi-processes over threshold dependent grids

In this paper, with motivation from Piterbarg VI [Discrete and continuous time extremes of Gaussian processes. Extremes. 2004;7(2):161–177] and the considerable interest in stationary chi-processes, we derive asymptotic joint distributions of maxima of stationary strongly dependent chi-processes on a continuous time and a uniform grid on the real axis. Our findings extend those for Gaussian cases and give three involved dependence structures via the strongly dependence condition and the sparse, Pickands and dense grids.     

教学机智：把“课堂意外”转化成“愉悦与收获”——以小学数学教学实践为例

教学机智是教师进行有效教学的必备素质,是充满教育智慧的行动。教师成为学生的"共同遭遇者"是教学机智在教学现场适时产生的心理基础;做学生的"智慧启迪者"是教学机智生成发展的行动方略;做教学的"持续反思者"是教学机智提升境界的必由之路。     

Assessing the missing data problem in criminal network analysis using forensic DNA data

Missing data is pertinent to criminal networks due to the hidden nature of crime. Generally, researchers evaluate the impact of incomplete network data by extracting or adding nodes and/or edges from a known network. Statistics on this reduced or completed network are then compared with statistics from the known network. In this study, we integrate police data on known offenders with DNA data on unknown offenders. Statistics from the integrated dataset (‘known network’) are compared with statistics from the police data (‘reduced network’). Networks with both known and unknown offenders are bigger but also have a different structure to networks with only known offenders.     

Faster maximum likelihood estimation of very large spatial autoregressive models: an extension of the Smirnov–Anselin result

Maximization of an auto-Gaussian log-likelihood function when spatial autocorrelation is present requires numerical evaluation of an n?×?n matrix determinant. Griffith and Sone proposed a solution to this problem. This article simplifies and then evaluates an alternative approximation that can also be used with massively large georeferenced data sets based upon a regular square tessellation; this makes it particularly relevant to remotely sensed image analysis. Estimation results reported for five data sets found in the literature confirm the utility of this newer approximation.     

A convex quadratic semi-definite programming approach to the partial additive constant problem in multidimensional scaling

Bénasséni [Partial additive constant, J. Statist. Comput. Simul. 49 (1994), pp. 179–193] studied the partial additive constant problem in multidimensional scaling. This problem is quite challenging to solve, and Bénasséni proposed a numerical procedure for two special cases: the cross-set partial perturbation and the within-set partial perturbation. This paper casts the problem as a modern quadratic semi-definite programming (QSDP) problem, which is not only capable of dealing with general cases, but also enjoys a number of good properties. One of the good properties is that the proposed approach can find the minimal constant under very weak conditions. Another is that there exists a ready-to-use numerical package such as the QSDP solver in Toh [An inexact path-following algorithm for convex quadratic SDP, Math. Program. 112 (2008), pp. 221–254], allowing a great deal of flexibility in choosing the index set to which the partial constant should be added. Our numerical results show a significant improvement over that reported in Bénasséni (1994).     

Constant hazard against a change-point alternative: a bayesian approach with censored data

A Bayesian approach to the problem of a constant hazard with a single change-point is developed using noninformative reference priors. We also present a generalization for the comparison for two treatments.     

非线性电感电路的过渡特性

文章对一个非线性动力学电路进行了研究，讨论了非线性RL电路物一些过渡特性。     

用WDMI型光栅单色仪研究钠原子光谱

用WDMI型光栅单色仪直接观测钠原子光谱双线的波长,确定了主量子数n,轨道量子数l,推算出各谱线的归属,并从谱线的裂距经过理论推证,分别计算出精细结构常数α、普朗克常数h和自旋量子数s,这3个重要常数的实测值与公认的理论值比较有较高精度.