基于FPGA的串行多节点数据采集传输系统的应用研究

多节点分布式传感器的数据采集与传输系统有着广泛的应用,其物理层实现主要分为串行及并行两种方式。针对特定的应用场景,选用串行传输的实现方式,设计以FPGA芯片、RS485芯片及AD芯片为核心的硬件平台,使用verilog语言设计FPGA的RTL（Register Transfer Level）逻辑代码,并在Modelsim中完成了功能仿真验证。最终实现了物理层为串行传输、传输层为总线模型的数据采集传输系统,该系统RTL代码设计简单,维护性强,可靠性高,占用芯片资源少,具有一定的工程应用价值。     

时钟芯片S-3530A与C8051F040单片机的通讯接口设计

串行实时时钟芯片S-3530A具有工作电压低、精度高、采用串行I2C接口等特点,在介绍该芯片工作原理的同时,给出了其与C8051F040单片机通讯接口的硬件电路和软件通讯设计。     

串行A/D、D/A与TMS320C6713的接口设计

介绍了串行A/D、D/A芯片MAX1270和DAC7734E,对于DSP上的串行接口McBSP(多通道缓冲串口)进行了细致的说明,给出了TMS320C6713与串行A/D、D/A接口芯片的硬件设计及软件实现。     

USB串行口三合一转换器设计

设计了一种串行数据测试工具,它采用PL-2303HX作USB接口的数据转换芯片,并通过工业通信接口芯片MAX232和MAX485把串行数据转换成RS232和RS485通信总线接口,实现了UART-TTL、RS232、RS485数据总线三合一的通用调试工具。     

用VHDL设计专用串行通信芯片

一种专用串行同步通信芯片(该芯片内部结构和操作方式以INS8250为参考)的VHDL设计及CPLD实现,着重介绍了用VHDL及CPLD设计专用通信芯片的开发流程、实现难点及应注意的问题。     

异步串行通信接口的IP核设计

异步串行通信接口(SCI)因其结构简洁、使用方便,因而在各类MCU、DSP和MPU芯片设计中获得广泛的应用。本文给出一种以状态机为控制核心、以数据流为执行中心的异步串行通信接口IP核结构设计的通用方法。此方法已在笔者所设计的DSP芯片中得到验证。     

MATLAB环境下的串行数据通信系统设计

本文提出了一种串行数据通信系统的设计方案,利用MATLAB提供的仪器控制工具箱serial类对象来实现串行数据通信,硬件设计中采用TL16C550C芯片使设计具有很好的可扩展性,用信号处理芯片TMS320VC5416为下位机的实验系统证明该方案进行数据通信与信号采集处理的可靠性。     

BRDF测量系统中高速串行接口的设计

本文探讨了BRDF测量系统中利用串行接口芯片EZ-USB FX2实现PC机与光谱仪之间的高速串行通讯.给出了系统组成原理,USB接口芯片EZ-USB FX2 CY7C68013的功能介绍和基于"Slave FIFOs"方式实现高速串行通讯的软硬件设计方法.     

MATLAB环境下的串行数据通信系统设计

本文提出了一种串行数据通信系统的设计方案,利用MATLAB提供的仪器控制工具箱serial类对象来实现串行数据通信,硬件设计中采用TL16C550C芯片使设计具有很好的可扩展性,用信号处理芯片TMS320VC5416为下位机的实验系统证明该方案进行数据通信与信号采集处理的可靠性.     

DS92LV18在光纤数据传输设计中若干问题的研究

DS92LV18是集串行编码器和解码器于一体的高性能串行解串器,是光纤数据传输设计中的理想器件,笔者以自身的设计体验,对该芯片在光纤数据传输设计中应该注意的问题进行了深入的研究,并给出了相应的解决方案。     

输入输出双线性系统的递推辨识与实现算法

本文对输入输出双线性系统给出了一套完整的辨识方法。首先给出了输入输出方程的一般形式,并对于一类规范型给出了相应地输入输出差分方程。然后给出了确定系统的结构指标和参数估计的递推算法,它改进了由Katta和Nurges(1984)给出的方法,大大缩短了计量时间。另外,还给出了状态方法的简单实现算法。最后,给出了仿真例子说明算法的有效性。     

Extrapolation of the boundary of uni- and bimodality of a two-component Gaussian mixture

A two-component Gaussian mixture with equal variances and various mathematical expectations has been studied. It has been found that a set of singular critical points of its probability density is a boundary of uni- and bimodality. The approximation equation of this boundary has been obtained on a line segment as a second-degree polynomial. The bifurcation area of the function being investigated is presented in the probabilistic form. The extrapolation algorithm of this boundary has been developed on a small line, and the experimental results have been presented.     

简体中文垃圾邮件分类的实验设计及对比研究

综合分析了垃圾邮件过滤的技术路线与方法,并在分析基于关键字的方法和统计学的方法的基础上,提出了将两者相结合,运用模式识别中的贝叶斯、最近邻和感知机等分类方法,实现对垃圾邮件的过滤的技术路线。以互信息最大化准则筛选出的特征集为基础,对不同分类技术的对比分析揭示了贝叶斯、最近邻和感知机在垃圾邮件过滤应用上的优劣。同时,文中对基于互信息最大化准则的垃圾邮件过滤应用提出了有益的思路。     

Substrate integrated non-radiative dielectric waveguide and its applications

In this article a Substrate Integrated Non Radiative Dielectric Guide (SINRD) has been realized with the concept of substrate integration circuits. In SINRD, a specific pattern of air holes have been used grooved in a dielectric substrate to reduce the effective dielectric constant of a particular region. Accordingly, design and implementation of SINRD guides and its applications in millimeter wave subsystems have been investigated by using published literatures. Thereby the concept has been utilized to develop an optimized design flow of SINRD transmission line. Design has been carried out at W band (85–110 GHz) on a high dielectric constant substrate and subsequently dispersion characteristics has been studied subject to transmitted and radiated field configuration.

     

在线考试系统智能组卷策略研究

表明智能组卷在考试系统中的核心地位,介绍组卷策略的基本要求,对智能组卷的策略进行了分析和研究,提出两种实现组卷策略的算法变换方式:相对评价组卷和绝对评价组卷。     

Thermo-elastic stress of a metal-matrix composite disc under linearly-increasing temperature loading by analytical and FEM analysis

In this study, the elastic stress analysis of a composite disc with aluminium matrix subjected to a linearly-increasing temperature distribution has been carried out. The values of tangential and radial stress components that have occurred under the effect of the temperature from the inner surface of the disc towards the outer surface have been obtained by two different methods, numerical and analytical. In the analytical analysis, a computer program has been developed to get the values of thermal stresses. But in the numerical study carried out with the finite-element method, Abaqus 6.8 package program has been used. As a result of these analyses, it has been observed that the stress values obtained from both methods support each other. It has been determined under this temperature distribution that tangential stress components are always on the condition of compression in the inner surface of the disc and of tensile in the outer surface. It has also been found out that radial stress components are always in the state of tensile along the whole profile of the disc. Finally, the stress analysis of the same composite disc subjected to this temperature distribution, but with a reduced mass, has also been examined numerically.     

Analysis of plates using isoparametric quadratic element—Shear,reaction, patch loading and some convergence studies

The derivation of reactions at the supported edge of a plate using isoparametric quadratic element has been presented. Straight and curved plates have been analysed to study the influence of shear rigidity, boundary conditions and support geometry on the value of shears and reactions at the edges. It has been found that convergence is slower for shear than for moments. The explicit value of the element loading matrix due to a patch load has been indicated, and plates having different aspect ratios due to a central patch load have been studied.     

A single period inventory model with a truncated normally distributed fuzzy random variable demand

In this article, a single period inventory model has been considered in the mixed fuzzy random environment by assuming the annual customer demand to be a fuzzy random variable. Since assuming demand to be normally distributed implies that some amount of demand information is being automatically taken to be negative, the model has been developed for two cases, using the non-truncated and the truncated normal distributions. The problem has been developed to represent scenarios where the aim of the decision-maker is to determine the optimal order quantity such that the expected profit is greater than or equal to a predetermined target. This ‘greater than or equal to’ inequality has been modelled as a fuzzy inequality and a methodology has been developed to this effect. This methodology has been illustrated through a numerical example.     

Dynamic response of a torsional micromirror to electrostatic force and mechanical shock

In this paper dynamic characteristics of a capacitive torsional micromirror under electrostatic forces and mechanical shocks have been investigated. A 2DOF model considering the torsion and bending stiffness of the micromirror structure has been presented. A set of nonlinear equations have been derived and solved by Runge–Kutta method. The Static pull-in voltage has been calculated by frequency analyzing method, and the dynamic pull-in voltage of the micromirror imposed to a step DC voltage has been derived for different damping ratios. It has been shown that by increasing the damping ratio the dynamic pull-in voltage converges to static one. The effects of linear and torsional shock forces on the mechanical behavior of the electrostatically deflected and undeflected micromirror have been studied. The results have shown that the combined effect of a shock load and an electrostatic actuation makes the instability threshold much lower than the threshold predicted, considering the effect of shock force or electrostatic actuation alone. It has been shown that the torsional shock force has negligible influence on dynamic response of the micromirror in comparison with the linear one. The results have been calculated for linear shocks with different durations, amplitudes, and input times.