基于有限状态机的SRAM分区地址发生器的设计与实现

根据多通道数据按分时方式保存于同一随机存储器中的不同分区空间的需求,设计了一种基于有限状态机设计方法的存储器分区地址产生电路.本文以8 Mb的SRAM为设计对象,采用有限状态机方式对随机存储器的读写地址的产生进行控制.将SRAM的存储空间划分为320×240的4个分区,每个分区空间的写地址不是连续产生而是以逐行扫描方式产生,使得4个通道的数据能够准确存储于对应分区的每个存储单元内.设计的顶层文件在QuartusⅡ软件环境下进行编译和时序仿真.仿真结果表明:采用有限状态机方法设计的分区地址产生电路能正确地实现SRAM分区地址的产生,并具有容易拓展的优点,为高速数据的存储工作方法提供了新的思路.     

一种超深亚微米SRAM存储单元的设计方法

首先分析了静态随机存储器（SRAM）6T存储单元结构的基本工作原理,为缩短仿真时间,构建了一种简化的SRAM电路,并通过仿真证实了此简化电路具有正确的读、写功能.鉴于本文仿真在TSMC180nm工艺下进行,且结合存储单元的W/L比例限制,最终选取了一组可行的晶体管尺寸.本文仿真均通过Hspice电路仿真软件进行仿真、验证.     

Automatic Generation of Setup for CNC Spring Coiler Based on Case-based Reasoning

When producing special-shape spring in CNC spring coiler,the setup of the coiler is often a manual work using a trial-and-error method.As a result,the setup of coiler consumes so much time and becomes the bottleneck of the spring production process.In order to cope with this situation,this paper proposes an automatic generation system of setup for CNC spring coiler us- ing case-based reasoning(CBR).The core of the study contains:(1)integrated reasoning model of CBR system;(2)spatial shape describe of special-shape spring based on feature;(3)coiling case representation using shape feature matrix;and(4)case similari- ty measure algorithm.The automatic generation system has implemented with C Builder 6.0 and is helpful in improving the automaticity and efficiency of spring coiler.     

Vehicle Active Damping Control with Considering Time Delay

A model predictive control (MPC) based active damping controller for automotive driveline oscillations with time-delay consideration is proposed.A simplified driveline model considering time delay is modeled and converted to a linear parameter varying state space equation.Based on the model and model predictive control theory,an active damping controller is designed for drivability and comfortability improvement.In order to verify the designed controller,a driveline with engine is modeled to simulate the tip-in/out driving operation.An MPC active damping controller without considering time delay is simulated together with the proposed controller.The simulation results show that,by adopting the new MPC active damping controller,the vibration of the vehicle is reduced and the drivability and comfortability are improved.     

Research on feasibility of missile attitude control based on laser gyroscope

According to the disadvantages of traditional mechanical gyro inertial measurement unit(’IMU’) for steering system not being available for missile attitude control, a concept based on laser gyro IMU is proposed to realize navigation & positioning and attitude control. The concept will save three single-axis rate gyros compared with traditional missile attitude control system, and is available both for strapdown and platform inertial navigation systems. Firstly, this article analyzes the selection requirements of sensitive device for missile attitude control system, and then analyzes the feasibility of missile attitude control based on laser gyro theoretically, on this basis, from four aspects of error characteristics, anti-vibration characteristics, temperature characteristics and dynamic characteristics, validate the feasibility of the concept practically. Secondly according to the strict requirements of dynamic characteristics on attitude control system, a special design is made for gyro signal filtering used for attitude control. By changing the traditional high order FIR filter to adaptive filter and low order FIR filter, laser gyro’s signal phase delay is reduced. The delay time of theoretical design is 1.5 ms. Lastly, this design is validated through an angle vibration test, and test curve indicates that the dynamic characteristics of laser gyro completely meets the requirements of the attitude control system, and the maximum delay time is 1.6144 ms, which satisfies with the attitude update rate of 2 ms per frame. This concept can simplify the missile guidance system design, at the same time, it does not reduce missile guidance accuracy, and also provides reference for the broadening of the application of laser gyro.     

Automatic pipes routing based on flow loss in electromechanical product

Based on flow loss,a new automatic pipe-routing algorithm is proposed for electromechanical product in 3D space,which consists of pre-processing and optimization search.Utilizing chaos theory,a chaos grid pre-processing model (CGPM) is established to efficiently pick up the solution space and reduce the search range in the pre-processing,which simplifies the optimization search.A modified particle swarm optimization (PSO) algorithm is presented to seek for an approximate optimal trajectory in the solution space in the optimization search based on standard PSO algorithm and migration characters of people.The comparison of experiments and analysis results shows that the modified PSO algorithm is capable of preventing prematurity effectively and searching for the optimal trajectory more efficiently.Theoretical analysis proves that the modified PSO algorithm converges at global optimum.The examples show that the automatic pipe-routing algorithm based on flow loss is effective and practical for electromechanical product.     

Optimization Method for Indoor Thermal Comfort Based on Interactive Numerical Calculation

In order to implement the optimal design of the indoor thermal comfort based on the numerical modeling method,the numerical calculation platform is combined seamlessly with the data-processing platform,and an interactive numerical calculation platform which includes the functions of numerical simulation and optimization is established. The artificial neural network (ANN) and the greedy strategy are introduced into the hill-climbing pattern heuristic search process,and the optimizing search direction can be predicted by using small samples; when searching along the direction using the greedy strategy,the optimal values can be quickly approached. Therefore,excessive external calling of the numerical modeling process can be avoided,and the optimization time is decreased obviously. The experimental results indicate that the satisfied output parameters of air conditioning can be quickly given out based on the interactive numerical calculation platform and the improved search method,and the optimization for indoor thermal comfort can be completed.     

Numerical simulation of the delay arming process of initiating explosive brakes

The delay arming process of initiating explosive( IE) brakes for fuse is complex and hard to be verified.A numerical simulation model of IE brakes was established based on the arbitrary Lagrange-Euler method.The model included the structure,the air filed,etc. The simulation boundary conditions were defined,including the contacts,blasting parameters of the explosive and the fluid-solid coupling interface. The simulation results show that the shear pin of the chosen IE can be cut off. When the piston needs to move 0. 8 cm,the time set to the delay arming of the IE brakes model is about 40 μs. The maximum displacement of the piston is 1. 17 cm. The model provides basis for parameters design and further improvement of IE brakes.     

一种基于存储器的正弦运算电路

基于存储器的正弦运算电路能够实现一种按照输入信号的正弦值变化的非线性运算。输入的信号经模数转换后,通过查找存储器EPROM表完成按正弦值转换,采用C语言来计算正弦函数值,按照模数、数模转换器的编解码的规则,用编程的方法,将生成4位16进制数的地址(输入)、函数值(输出)写到存储器中,随后再次通过数模转换器转换成模拟信号输出。该电路对于连续输入的信号有可靠的转换精度,为实现一种基于正弦函数的混沌电路提供了可能。     

基于DSP的条码标尺识别系统研究

条码标尺的识别系统是数字水准仪中最重要的组成部分.基于DSP的条码标尺识别系统的设计原理与硬件电路实现方案,对条码识别的软件算法进行了研究.以DSP为核心,扩展FLASH和SRAM作为程序存储器和数据存储器,执行核心的识别处理算法,并控制前端CCD和A/D转换器的数据采集.系统以液晶显示和键盘输入作为人机交互界面.     

Small-Scale CMOS Pseudo SRAM Module Design

An approach to design small scale CMOS static random access memory (SRAM) is proposed. The design of address decoder, memory cell, and the layout are included. This approach adopts flip-flop array structure.The flip-flops are used as the storage cells and they are stacked to form the whole SRAM module. The word select bit is generated from the address decoder. And one word at a time is selected for reading or writing. The design of the memory core‘s layout is also discussed since it should be optimized to save area and also should be convenient for realization. It‘s a full-custom layout. The address decoder is composed of combinational logic circuit and its layout is also designed as a full-custom layout. With all these modules, the integral structure of the SRAM is cartied out.     

基于SVM的光伏最大功率跟踪的预测研究

针对光伏组件中常用的最大功率跟踪方法存在的不足,将支持向量机用于预测光伏组件的最大功率点工作电压.支持向量机是一种新型的机器学习方法,该方法以结构风险最小化原则取代传统机器学习方法中的经验风险最小化原则,在小样本的机器学习中有着优异的性能.根据光伏组件的特点和最大功率点工作电压的影响因素,建立了支持向量机的最大功率点工作电压预测模型.实际仿真分析表明,与BP神经网络的模型相比,支持向量机的模型具有更高的预测精度.     

PCMCIA卡式低频振动波形数据记录器

介绍了低频振动波形数据记录器的电路基本结构和工作程序 ,重点叙述了PCMCIA存储卡结构 ,指出采用PCMCIA存储卡后 ,可省去将数据传输至微机的时间 ,大大提高工作效率 ,并且为今后扩大记录器的数据存储容量提供途径 .PCMCIA存储卡采用 8片NV SRAMDCM851 2B ,4兆字节 .记录器适用于工作频带为 0～ 90Hz的低频振动测量 ,可供多达 1 2 8次记录 ,每次记录至少 1min (即 1页 ) ,总记录时间超过 2h.     

基于TCL语言和边界扫描技术的存储器测试脚本设计

为了提高存储器的边界扫描测试软件的通用性,提出一种基于TCL语言及边界扫描技术的存储器测试脚本设计方案。结合存储器测试理论及边界扫描逻辑簇测试技术,研究基于TCL脚本语言的存储器测试脚本设计方法,用以在进行存储器簇测试时描述存储器自身的读写特性及与其外部边界扫描测试单元的连接关系等,并给出HY6264SRAM静态存储器功能测试的例子。通过测试验证,使用TCL脚本语言与高级语言联合编程能够提高边界扫描测试软件的工作效率。     

星载存储器吞吐率瓶颈与高速并行缓存机制

为解决目前星载存储器无法有效支持多路高速数据并行存储的问题,针对载荷数据高速输入需求,对基于NAND Flash的固态存储器的吞吐率瓶颈进行分析,根据固态存储器的固有写操作特性对有效吞吐率的影响,提出了四级流水线操作和总线并行扩展方案;针对多通道数据并行存储、流水线加载连续性等需求,对使用现场可编程门阵列FPGA(Field-Programmable Gate Array)内部双端口随机存取存储器RAM(Random access memory)、外置静态随机存取存储器SRAM(Static Random Acess Memory)等已有缓存方案的不足进行分析,完成了基于同步动态随机存储器SDRAM(Synchronous Dynamic Random Access Memory)的方案可行性分析与新型存储单元架构设计,最终提出了基于SDRAM的高速多通道缓存与存储协同调度方案.模型仿真与原型功能验证结果表明,方案在极限工况下可将4路高速文件数据连续并行接收缓存至SDRAM中,并可根据各分区缓存状态将文件数据按优先级自主动态写入Flash中,期间缓存无溢出,并最终进入常规动态平衡调度状态,实现了对多路高速载荷数据的并行接收缓存和自主调度存储,且存储器的数据吞吐率可达1.2Gbps,能够满足未来星载存储器对多路高速载荷数据存储的需求.     

基于DBL结构的嵌入式64kb SRAM的低功耗设计

针对嵌入式系统的低功耗要求,采用位线分割结构和存储阵列分块译码结构,完成了64kb低功耗SRAM模块的设计．与一般布局的存储器相比,采用这两种技术使存储器的功耗降低了43%,而面积仅增加了18%．     

磁阻式随机存储器MRAM在片上高速缓存方面的应用

介绍MRAM在不同层次的高速缓存方面的应用,讨论了如何用MRAM构建高速缓存,并与传统的SRAM和DRAM进行了比较,介绍了提高MRAM性能和降低其功耗的新方法。     

基于FPGA的以太网与E1协议转换器的实现

介绍了采用Xilinxspartan2系列FPGA芯片,配以异步SRAM,完成了以太网数据流和E1数据流之间的相互转换,并给出了SRAM接口模块和HDB3编码模块的算法设计流程及相关仿真结果。     

解析法提取分段线性混沌系统周期轨道的研究

采用解析法研究提取分段线性混沌系统周期轨道．分段线性混沌系统的状态空间被数个切换面分割成若干个线性子区间．联合求解周期轨道在各子区间的解方程,可得该周期轨道在各切换面的坐标及在各子区间的运行时间,从而得到所提取周期轨道的分段解析表达式．与传统的数值提取法相比,所提出的解析法具有提取的周期轨道精确度高、周期轨道信息的存储量小、便于实时应用、易于进行稳定性分析和控制等优点．应用该解析方法分别求得三阶蔡氏电路和四阶蔡氏电路混沌吸引子中许多周期轨道,验证了该方法的可行性和实用性．