制导武器传感器网络异类信息系统的统一表示

分析了当前精确制导武器由多源异类传感器组成的特点,提出了传感器网络的概念,怎样对这些多源异类传感器网络信息进行统一描述和表达,是应用当前比较成熟的信息融合理论的基础;基于异类信息的特点及目标各子特征之间的正交性,给出了多源异类信息系统的统一表示形式和多源异类Kalman滤波算法。因此,可为提高制导武器的打击精度以及武器装备在复杂战场环境下的战斗力与生存力提供理论依据。     

Optimizing reactive volt-ampere regulating devices in transmission systems using a full three-phase representation

A technique is presented for optimizing the locations and sizes of reactive volt-ampere regulating devices in transmission networks or for optimal control of existing devices. The technique is based on linear programming concepts. It uses a full three-phase representation of the transmission network and is therefore capable of analysing systems with unbalanced loads. The technique is also capable of optimizing with both positive and negative variations in the values of the regulating devices. The new technique is applied to an example system and the results are presented.     

Focused ion beam-based fabrication of nanostructured photonic devices

This paper presents results for focused ion beam (FIB) processing of two photonic devices: 1) a GaN laser with a fourth-order grating for vertical emission, and 2) a two-dimensional (2-D) photonic crystal (PhC) structure. For the GaN laser, both L-I and I-V results are shown before and after etching, and vertical emitted power as a function of the distance along grating is shown. A finite element (FE)-based electromagnetic model is developed to support the measured results and is used to predict the optimum grating depth. For the 2-D photonic crystal, direct FIB etching is used to create a PhC in a standard InP waveguide structure. Measured and modeled transmission results are compared, and there is good agreement for band edge position. A detailed study of hole shape is presented, and this leads to the development of a multistage etching procedure involving both reactive ion etching and inductively coupled plasma etching. This results in a much improved hole shape.     

Underwater acoustics: Propagation,devices and systems

The word acoustics originates from the Greek word meaning “to listen.” The original meaning concerned only hearing and sound perception. The word has gradually attained an extended meaning and, in addition to its original sense, is now commonly used for almost everything connected with rapidly varying mechanical vibrations, from noise to seismic and sonar systems, to ultrasound in medical diagnosis and materials technology. An important technical application of acoustics is related to undersea activities, where acoustic waves are used in much the same way that radar and electromagnetic waves are used on land and in the air-for the detection and location of objects, and for communications. The reason that acoustic rather than electromagnetic waves are used in seawater is simple: electromagnetic waves are strongly attenuated in salt water and would, therefore, have too short a range to be useful for most applications. This paper gives an introduction to underwater acoustics and an overview of the field of sonar engineering with emphasis on factors that affect range and performance. Invited paper at POLECER International Conference, Piezoceramics for end-users II, March 5–8, 2006, Hafjell ,Lillehammer-Norway.     

Microdischarge arrays: a new family of photonic devices

The optical and electrical characteristics of microdischarge devices and arrays fabricated in semiconductors and metal/polymer structures are described. Devices as small as (10 μm)² in emitting area (nanoliters in volume) and arrays as large as 30 × 30 have been demonstrated and operated at gas pressures up to and exceeding one atmosphere. This new generation of microoptical sources is capable of producing photons from the infrared to the vacuum ultraviolet and beyond and is well suited for integration with microoptoelectronic, fluidic, and mechanical systems     

Microdischarge arrays: a new family of photonic devices

The optical and electrical characteristics of microdischarge devices and arrays fabricated in semiconductors and metal/polymer structures are described. Devices as small as (10 μm)² in emitting area (nanoliters in volume) and arrays as large as 30 × 30 have been demonstrated and operated at gas pressures up to and exceeding one atmosphere. This new generation of microoptical sources is capable of producing photons from the infrared to the vacuum ultraviolet and beyond and is well suited for integration with microoptoelectronic, fluidic, and mechanical systems     

电力电子和FACTS装置数字仿真软件包的研究与开发

介绍新研发的电力系统电力电子及FACTS装置仿真软件包EMTPE，其中包括电力电子装置的数值计算方法、大量全控型电力电子器件的模型、相量实时测量控制模块、过电压闪络率计算方法、工作平台与人机界面、总体合成及FACTS装置仿真等。给出一些算例以演示新计算方法的效果。     

Optical MEMS for photonic switching-compact and stable optical crossconnect switches for simple, fast, and flexible wavelength applications in recent photonic networks

We review the development trends and state-of-the-art technologies of large-port-count optical switches over the past decade. Practical implementation of optical switch fabrics is discussed in terms of optical switch architectures, optical configurations, port counts, switch elements, and so on. We describe compact and stable optical crossconnect three-dimensional microelectromechanical systems (3-D-MEMS) switches that are a key technology in recent photonic networks. To show how these enable simple, fast, and flexible wavelength applications in the photonic layer, we discuss the fast and stable MEMS switching by novel comb actuator and V-shaped torsion bar, compact optical configuration with roof-type mirror, stable switch housing with cubic structure, packaging techniques by tolerance expansion and simple procedures of the component assembly, MEMS mirror controller with fast and low power digital notch circuit, reliability by shock absorption, and field trials. In addition, we discuss the impact of these switches on system integration for recent metropolitan area networks and enterprise networks.     

Monte Carlo simulation of nanoelectronic devices

The Monte Carlo simulation method is used to analyze the behavior of electron and hole mobility in different nanoelectronic devices including double gate transistors and FinFETs. The impact of technological parameters on carrier mobility is broadly discussed, and its behavior physically explained. Our main goal is to show how mobility in multiple gate devices compares to that in single gate devices and to study different approaches to improve the performance of these devices. Simulations of ultrashort channel devices taking into account quantum effects are also shown.     

Concurrent multiscale simulation of electronic devices

In this paper we present a multiscale framework for the simulation of electronic devices allowing the coupling of continuum and atomistic models in a transparent way. We introduce the basic features of the TiberCAD simulation software which is based on the multiscale simulation concept, and we show a simulation example to illustrate the basic aspects of a multiscale simulation.     

Modelling of photonic bandgap devices by the leaky mode propagation method

Main modelling approaches used for investigating the Photonic bandgap (PBG) devices are reviewed. In particular, the model based on Leaky Mode Propagation (LMP) method is described. A complete analysis of the propagation characteristics, including the determination of modal propagation constants, electromagnetic field harmonics and total field distribution, transmission and reflection coefficients, total forward and backward power flow in the structure, guided and radiated power, and total losses, can be carried out by a computer program based on the LMP approach. The numerical results have been validated by comparisons with those obtained by using other more complex and expensive models. The new model shows some significant advantages in terms of very low computational time, absence of any a priori theoretical assumptions and approximations, capability of simulating the actual physical behaviour of the device and fast determination of the bandgap position.Copyright © 2003 John Wiley & Sons, Ltd.     

Piecewise-linear modelling and simulation of nonlinear networks

This paper presents a method which combines the modelling and simulation of a nonlinear network together. The main idea is to divide the rectangle of interest into simplices by imposing a fixed ordering. It turns out that the creation of a piecewise-linear model and the computation of an approximate solution are greatly simplified because of the use of simplices. Some examples show that it is possible to apply the method to ‘fixed point’ problems and other types of problems.     

Optimization of linear systems for 3D parallel simulation of semiconductor devices: Application to statistical studies

The 3D simulators are nowadays essential in semiconductor device modelling in order to study fluctuation effects when devices are scaled to gate lengths approaching nanometre dimensions. To take into account these effects it is necessary to perform statistical studies, which have a high computational cost. The resolution of the linear systems generated by the discretization of partial differential equations is the most time‐consuming part of the simulation process. In this paper we propose an optimization of the linear system solution procedure based on domain decomposition methods implemented in a 3D parallel drift–diffusion device simulator. We have also carried out an analysis of the parallel performance of the device simulator. Numerical results show superlinear efficiency values up to 62 processors in the solution of the Poisson equation. The results were obtained on a Cluster HP Integrity Superdome. Copyright © 2008 John Wiley & Sons, Ltd.     

一种射频信号测量的频谱分析及仿真

介绍了一种射频信号测量和频谱分析过程中误差的成因及减小误差的主要方法.在信号测量过程中由于测量环境和条件不同,测量的要求不同,测试者对测量方法的理解不同,得到的测量结果存在偏差.对得到的连续信号进行时域采样并截取以得到有限长的离散序列,利用计算机DFT实现信号频谱分析,通过与理论值的对比,发现了测量及分析过程中产生的各种干扰及误差,对其进行了分析及提出修正办法,进行了基于MATLAB环境下的仿真效果.     

CCM-CPM反激变换器小信号建模与仿真

基于状态空间平均法对连续峰值电流模式(CCM-CPM)反激变换器闭环系统建立了小信号数学模型,并利用Matlab/sisotool工具分别设计了电压模式(VM)和峰值电流模式(CPM)两种工作模式下的控制器类型及其补偿参数,分析对比了两种工作模式对系统的开环频率特性和闭环音频纹波衰减率的影响,通过PSIM仿真验证了理论分析和数学模型的正确性。     

2215线性调频脉冲信号及其仿真

线形调频信号可以获得较大的压缩比,有着良好的距离分辨率和径向速度分辨率,是目前雷达信号采用的主要形式.本文主要分析了线性调频脉冲信号的模型及其匹配滤波器输出形式,并通过MATLAB仿真进行理论验证,结合雷达的实际工作模式给出了实际信号处理流程.     

A spreadsheet simulation of logic networks

The authors present a method for simulating logic networks using spreadsheets. This method may be used to simulate combinational, sequential, synchronous and asynchronous networks. The characteristics of the method make it significant as an important tool in the analysis, design and test logic networks in education environments