Implementation of RNS-Based Distributed Arithmetic Discrete Wavelet Transform Architectures Using Field-Programmable Logic

Currently there are design barriers inhibiting the implementation of high-precision digital signal processing (DSP) objects with field programmable logic (FPL) devices. This paper explores overcoming these barriers by fusing together the popular distributed arithmetic (DA) method with the residue number system (RNS) for use in FPL-centric designs. The new design paradigm is studied in the context of a high-performance filter bank and a discrete wavelet transform (DWT). The proposed design paradigm is facilitated by a new RNS accumulator structure based on a carry save adder (CSA). The reported methodology also introduces a polyphase filter structure that results in a reduced look-up table (LUT) budget. The 2C-DA and RNS-DA are compared, in the context of a FPL implementation strategy, using a discrete wavelet transform (DWT) filter bank as a common design theme. The results show that the RNS-DA, compared to a traditional 2C-DA design, enjoys a performance advantage that increases with precision (wordlength).     

CD++: a toolkit to develop DEVS models

The features of a toolkit for modeling and simulation based on the DEVS formalism are presented. The tool is built as a set of independent software pieces running on different platforms. Not only are the main characteristics of the environment presented, a focus on its use is also considered by inclusion of application examples for a variety of problems. Many models can be defined in an automated fashion, simplifying the construction of new models and easing their verification. The use of this formal approach has allowed the development of safe and cost‐effective simulations, significantly reducing development time. Copyright © 2002 John Wiley & Sons, Ltd.     

硬件握手双向选通型串行通信共享器的设计

本文介绍了ＩＢＭ－ＰＣ系列计算机通过ＲＳ－２３２Ｃ串行口与多个单片微机组成的分布式系统中一种可双向选通串行通信共享器的设计方法。给出通信共享器的设计电路；并对电路工作原理进行了详细剖析。     

Tracking Control and Synchronization for Two-Dimension Discrete Chaotic Systems

1　ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｎｃｅ 1 990 ,ｃｈａｏｔｉｃｓｙｎｃｈｒｏｎｉｚａｔｉｏｎ[1～ 4] ａｎｄｃｈａｏｔｉｃｃｏｎｔｒｏｌｌｉｎｇ[5～6] ｈａｖｅｒｅｃｅｉｖｅｄａｇｒｅａｔｄｅａｌｏｆａｔｔｅｎｔｉｏｎ[7～1 1 ] ,ａｎｄｃｈａｏｔｉｃｓｙｎｃｈｒｏｎｉｚａｔｉｏｎｉｓａｐｈｅｎｏｍｅｎｏｎｏｆｉｎｔｅｒｅｓｔｉｎｆｉｅｌｄｓｆｒｏｍｅｌｅｃｔｒｏｎｉｃｓｔｏｃｏｍｍｕｎｉｃａｔｉｏｎ[1 2 ] ,ａｎｄｆｒｏｍｂｉｏｐｈｙｓｉｃｓｔｏｎｅｕｒｏ ｓｃｉｅｎｃｅ[1 3] .Ｉｆｃｈａｏｔｉｃｓｙｎｃ…     

用红外热象技术研究有凸台热源倾斜板的散热

本文介绍红外热象技术在工程热物理研究中某些应用的探索。作为实例，通过热象技术，实验研究了具有水平凸台离散热源的倾斜板的散热，在研究它的自然对流换热部份结合利用激光全息干涉技术。此间着重于分析倾斜角对散热的影响。     

非串行生产线的建模,分析及设计

本文利用等效工作站理论和工件流平衡原理，推导出非串行离散事件生产线可以等价于串联系统，并归结为装配和拆卸两条定理，解决了系统的建模、分析与设计问题。     

Locked discrete event systems: How to model and how to unlock

To model qualitative aspects of discrete event systems, i.e., the order of the events is of sole importance, we use a triple consisting of the set of all possible events (the alphabet), the set of all behavior (possible strings of events), and the set of all tasks (completed behavior). We use this view to model synchronous as well as asynchronous connection of systems. Moreover, it is easy to define notions like deadlock and livelock in this view. We give a method to construct a second system that, in connection with the original system, gets rid of its deadlock and/or livelock. A state-space representation is introduced. In this representation computations can be done effectively.     

一种便于观测的信号抽样及复原方法

利用倍频器，将重复频率与连续信号ｔ（ｔ）的频率相同的方波进行若干次倍频后，对连续信号进行抽样，从而获得离散的抽样信号ｆｓ（ｔ），再利用有源低通滤波器使其复原成连续信号ｆ（ｔ）。避免了一般抽样器不便于观测的缺点。     

神经网络离散变结构控制的算法及其应用

本文首次将自适应线性神经元（Ａｄａｌｉｎｅ）用于离散变结构控制。以滑模面Ｓ（ｋ）＝０作为Ａｄａｌｉｎｅ元的希望输出，作为Ａｄａｌｉｎｅ元的实际输出，通过ＬＭＳ算法在线调整权值可保证滑态可达条件的满足。应用所提出的控制策略对泵控马达速度伺服系统进行控制，仿真表明控制效果是令人满意的。     

扩展有限递归进程模型

主要讨论离散事件动态系统的建模问题。由ＫＩｎａｎ和ＰＶａｒａｉｙａ提出的有限递归进程（ＦＲＰ）是描述并发离散事件动态系统的有力工具，但在其ＦＲＰ中，没有定义对数据变量的操作和条件转移算子。本文扩展ＦＲＰ包括这两方面内容。最后举例说明扩展ＦＲＰ的描述能力。