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1.
Chao Zhang 《Operations Research Letters》2011,39(1):78-82
In this paper we show the solvability of the expected residual minimization (ERM) formulation for the general stochastic linear complementarity problem (SLCP) under mild assumptions. The properties of the ERM formulation are dependent on the choice of NCP functions. We focus on the ERM formulations defined by the “min” NCP function and the penalized FB function, both of which are nonconvex programs on the nonnegative orthant. 相似文献
2.
研究一种能够进行远程及绝对测量的光纤低相干干涉传感系统。该系统包含两个光纤干涉仪,其中一个光纤干涉仪置于被测场中感应被测量的变化,可实现远程测量;另一个光纤干涉仪解调被测量的值。运用波分复用技术,使用于解调的光纤干涉仪同时工作于低相干干涉和高相干干涉状态。用低相干干涉信号决定被测量的幅值,对被测量实现绝对测量,并使测量量程不受波长限制;同时,用高相干干涉信号对被测量进行高精度的测量。系统的测量量程为6mm,测量分辨率小于1nm,位移实验结果的线性相关系数R为0.99。 相似文献
3.
提出了采用截止波导法与谐波混频法相结合的方式,进行0.14 THz高功率短脉冲的频率测量.首先将两个截止频率分别为0.125和0.15 THz的非标准矩形波导作为接收端,通过截止波导滤波法获得了太赫兹辐射源的频率范围.然后根据已知的频率范围,将本振频率选择为15—20 GHz,则谐波混频的谐波次数确定为8.随后的Ka波段的脉冲测试和0.14 THz连续波测试表明,该8次谐波混频器可用于0.14 THz脉冲的混频测量.最后,0.14 THz脉冲频率测量实验给出了太赫兹辐射源的准确频率为0.1465 THz.该方法大大降低了对本振信号的频率要求,且结果准确可信,为长波段太赫兹脉冲的频率测量提供了一种新的思路.
关键词:
太赫兹脉冲
截止波导
谐波混频 相似文献
4.
快速有效地获得多级联光纤光栅法布里-珀罗(F-P)腔的光谱特性,是优化设计基于上述结构建立的级联多波长激光器、放大器等各种光器件以及复杂分布式传感网络的重要基础和保障.将V-I传输矩阵法用于光纤光栅F-P腔反射光谱特性的分析,并建立了V-I传输矩阵模型.采用该模型对三种不同结构的光纤光栅F-P腔在不同参数下的光谱特性进行分析,并与传统多层膜法的分析结果相比较,表明V-I传输矩阵法能够在保证分析精度的前提下大大节省运算时间.实验结果表明,V-I传输矩阵法对光纤光栅F-P腔谱特性的分析结果比耦合模法更准确.
关键词:
V-I传输矩阵法')" href="#">V-I传输矩阵法
光纤光栅法布里-珀罗腔特性
分析精度
运算时间 相似文献
5.
PVK三线态激基复合物的发光及其受紫外光辐照的影响 总被引:1,自引:0,他引:1
用不同溶剂中的前驱物旋涂成PVK层,制备了ITO/PEDOT ∶ PSS/PVK/Ca ∶ Al器件,以及相同结构不同PVK分子量的器件。通过测试分析认为:器件的电致发光谱中590 nm波长处的发光峰来自于PVK三线态的激基复合物,并且发现其强度依赖于PVK的分子构型,即在PVK分子中相邻咔唑基团重叠程度。通过比较不同紫外辐照剂量后的PVK器件的发光,发现适度的UV辐照后的PVK分子构型中相邻咔唑基团处于全重叠的状态增加,在电致发光时会形成更多的三线态激子,因而提高了PLED器件的发光效率。 相似文献
6.
Changshi Yu Yunhua Xu Shijie Liang Xudong Jiang Guitao Feng Cheng Li Weiwei Li 《中国化学快报》2018,29(2):325-327
Star-shaped electron acceptors based on perylene bisimide as end groups and spiro-aromatic core linked with ethynyl units were developed for nonfullerene solar cells. Ethynyl linkers are able to improve the planarity of conjugated backbone, resulting in enhanced electron mobility and power conversion efficiency in solar cells. 相似文献
7.
This review supplied direct insight of host-guest molecule system by using COR as the guest molecule. 相似文献
8.
In this paper we provide a solution of the functional equation unsolved in the paper, by the second author, "On functional equations arising from map enumerations" that appeared in Discrete Math, 123: 93-109 (1993). It is also the number of combinatorial distinct rooted general eulerian planar maps with the valency of root-vertex, the number of non-root vertices and non-root faces of the maps as three parameters. In particular, a result in the paper, by the same author, "On the number of eulerian planar map... 相似文献
9.
Tie-Jun Liu Yue-Sheng Wang Chuanzeng Zhang 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(4):267-282
The main interest of this study is a new method to solve the axisymmetric frictionless contact problem of functionally graded
materials (FGMs). Based on the fact that an arbitrary curve can be approached by a series of continuous but piecewise linear
curves, the FGM is divided into a series of sub-layers with shear modulus varying linearly in each sub-layer and continuous
at the sub-interfaces. With this model, the axisymmetric frictionless contact problem of a functionally graded coated half-space
is investigated. By using the transfer matrix method and Hankel integral transform technique, the problem is reduced to a
Cauchy singular integral equation. The contact pressure, contact region and indentation are calculated for various indenters
by solving the equations numerically.
An erratum to this article can be found at 相似文献
10.
Design method for fluid viscous dampers 总被引:2,自引:0,他引:2
Jia Jiuhong Du Jianye Wang yu Hua Hongxing 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(9):737-746
A basic design method of doubly acting fluid viscous dampers with double guide bars is presented. The flow of the viscoelastic
fluid between two parallel plates, one of which is started suddenly and the other of which is still, is analyzed. According
to this solution, the velocity and the shear stress of the fluid at the fringe of the piston are solved approximately. A mathematical
model of viscous dampers is derived, and the shock test is carried out. From experimental results, the parameters of the mathematical
model are determined. Consequently, a semi-empirical design equation is obtained. Applying this equation to a certain practical
damper, the damping material is chosen and the physical dimensions of the damper are determined. Shock tests using this damper
are performed. Theoretical results are in good agreement with experimental results, which validates the reliability of the
calculated physical dimensions of the specimen damper and the validity of the basic design equation.
An erratum to this article can be found at 相似文献