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°．     

复合伺服液压系统在压力机的应用

针对传统压力机液压系统能耗较高等不足,采用二伺服泵及开关型电动阀通过PID控制器进行控制的复合伺服 液压系统,设计了新型压力机( press servo hybrid,PSH);进行了液压系统主要部件设计计算和选型;利用AMESim软件对 新系统与传统液压系统进行建模和仿真比较,结果表明新系统同样能满足按VOITH公司技术要求,能耗有非常显著的 降低。     

自动全方位纸箱折页封箱机的设计

针对市场上纸箱包装需求量大,且对纸箱包装效果要求高的情况,为了减轻纸箱包装工的劳动强度,在现有包装 生产线的基础上,设计了一种自动全方位纸箱折页封箱机。该设备由机架、折页机构、夹箱机构和毛刷机构等组成。利 用光电感应技术,基于三菱PLC设计了该机的控制系统。该设备能自动适应各种尺寸规格的瓦楞纸箱,完成不同规格 纸箱的封箱要求;同时,在光电感应的基础上,设计了自动夹箱机构,实现了有序封箱。该设备能扩大纸箱包装范围、提 高包装质量、降低劳动强度。     

境外居留权、控制方式与研发国际化——来自中国创业板和中小板上市公司的经验证据

文章以2007-2015年中国创业板和中小板上市公司为样本,考察上市公司的实际控制人取得境外居留权对研发国际化(以公司建立海外研发中心来衡量)的影响.实证结果显示,上市公司实际控制人境外居留权能够带来积极的经济后果,对上市公司海外研发具有显著正向影响,且这一效应在实际控制人直接控制上市公司的样本中,在行业竞争激烈的情况下,更为显著.文章拓展了实际控制人取得境外居留权的经济后果研究,深化了实际控制人个人特征影响公司治理的研究,同时也有助于企业利用各项资源开展海外研发,提升公司竞争力.     

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。     

双线性离散系统的全局可镇定性

讨论了一类多输入多输出（MIMO）离散双线性系统的全局可镇定性。利用Lyapunov稳定性方法和分离原理,得到降阶动态输出反馈镇定控制器的设计。     

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).