多项式矩阵理论在网络分析中的应用

本文应用基本回路矩阵Ｂ、基本割集矩阵Ｑ和支路伏安特性矩阵［Ｙ（ｓ）Ｚ（ｓ）］列写出线性时不变有源网络的网络矩阵Ｐ（ｓ），借助于多项式矩阵理论中有关解耦零点的概念和理论，研究了网络的复杂度和稳定性。和文献［３］相比，不仅降低Ｐ（ｓ）阶次，减少了运算，且研究了复杂度。     

线性电路交流分析程序LACAP

阐述线性电路交流分析程序LACAP(Linear Ac Analysis Program)设计的基本原理与计算技术;提出提高运行效率的几项主要技术措施;并给出程序的总体框图和一个典型的运行实例。     

A unified pole-zero module for linear transfer functions

A new module-theoretic tool is presented for the study of linear time-invariant input/output maps (‘transfer functions’). For suitable subrings of the field k(s) of rational functions, an O-module called the structure module can be attached to each transfer function. This structure module naturally contains the classical (Kalman) pole module as a submodule which gives the (Wyman-Sain) multivariable zero module as the corresponding factor module. A posteriori the resulting exact sequence splits, and the structure module is isomorphic to the direct sum of the pole module and the zero module. Calculations over local rings echo valuation-theoretic results obtained by Kung and Kailath.     

Biomechanical evaluation of bike power saver

Bike power saver (BPS) is a new product that claims to change the angle of pedaling forces and reduce applied power dead range (Chic Sheng Industrial Co., Ltd, Taiwan, China). In order to determine its effectiveness, we quantified how BPS operates through a 3D kinematical study and electromyography (EMG) analysis of leg muscles during pedaling. Ten kinesiology students participated in this study. A 3D motion capture system consisting of nine high-speed cameras (VICON v8i, a capture rate of 120 frames/s) was used to collect the total body and pedal motion with and without BPS at statically determined low, middle and high intensity cycling levels. The short-time test (14s) was applied to all intensity levels while the long-time test (30 min) was applied only to the low wattage level. Wireless EMG was synchronized with the 3D motion capture system to monitor the right and left tibialis anterior, gastrocnemius, quadriceps and hamstring. The results revealed that BPS did not alter hip and knee movement significantly (p>0.05), but it did vary ankle movement. BPS caused a movement change in the pedals, and consequently induced instability in ankle control. The altered pedal movement led to an increase in activity level and presumably also energy expenditure for dominant muscles, resulting in a faster fatigue process. From these data, it is likely that the BPS actually requires more effort than a standard bike.     

Regional Flood Frequency Analysis in Tunisia: Identification of Regional Distributions

Best-fit distributions of floods in Tunisia are determined based on L-moment diagram and statistical tests. GEV and GLO distributions provided the best fit to seven and three regions of Tunisia respectively. In each homogeneous region, hierarchical approaches and regression models were developed for gauged and ungauged watersheds. The first two parameters of the distributions (GEV and GLO) were estimated from measured data while the third parameter was represented by the regional average value weighted by the record length of all stations in the region. The obtained parameters were correlated to the catchment size. Quantiles obtained by the proposed models were compared with those obtained using local conventional models. Statistical tests showed that the proposed models provided a much better agreement with observed floods than any of the conventional methods generally used in Tunisia.     

分层空时码多载波CDMA的译码与检测

研究V－BLAST MIMO MC－CDMA下行系统。提出了一种对每个子载波进行V－BLAST译码的非线性 算法,对不同天线数、用户数情况进行了系统的仿真和分析,并对V－BLAST译码的线性和非线性算法进行了系 统仿真比较。     

供应商管理库存(VMI)系统的开发与应用

为协调及时供货与库存控制之间的关系,缓解库存资金紧张、供应不及时的矛盾,降低库存资金占用,保证供应的及时性,济钢材料处结合管理模式和业务流程的特殊性,基于ERP系统,开发出满足自身对库存控制需求的VMI系统,从而提高了材料管理水平,首次实现了关键材料的“零库存”管理,填补了济钢VMI管理信息化的空白。     

混频频率的最佳选择

本文推出一种简便的混频频率选择法,试图解决混频器的组合干扰问题.文中定义了组合波的干扰程度,并列表给出了不同中频频率的各阶组合波的相关信号及本振频率.     

PBR-MⅡ型~87Rb激射器的改进及短期频率稳定度测量

介绍了PBR-MⅡ型铷激射器物理部分及电路系统的改进;测量了改进后激射器的输出功率及短期频率稳定度,其结果有明显提高,并对结果进行了拟合、分析,其噪声特性与理论相符。