基于PowerPC603e通用处理模块的设计与实现

Power PC系列处理器是高性能、低功耗的32位嵌入式处理器.Power PC系列处理器在嵌入式系统中得到了广泛的应用,文章简要介绍了Power PC603e处理器的特点,详细阐述了基于Power PC603e的通用处理模块的组成、原理以及60x总线存储器控制器在FPGA上的设计与主要时序的产生.此FPGA控制器可提供60x总线与多种类型的SRAM、FLASH和I/0的接口,已在嵌入式系统的设计中得到了应用和验证.     

PC与松下FP系列PLC的通信

本文介绍了PC与松下FP系列PLC的通信。PC端程序采用VB6.0开发,通过MSComm控件,按照松下PLC MEWTOCOL-COM协议,实现了PC通过RS-232的方式,和松下PLC的通信的目的。着重介绍了松下MEWTOCOL-COM协议的内容,以及MSComm控制的一些常用的事件和属性。     

扩展PC输入接口的方法

介绍了应用于PC控制系统的3种扩展PC输入接口的方法,并给出了采用日本立石电机株式会社(OMRON)生产的C系列PC的软件与硬件。     

PC与松下FP系列PLC的通信

本文介绍了PC与松下FP系列PLC的通信。PC端程序采用VB6.0开发,通过MSComm控件,按照松下PLC MEWTOCOL-COM协议,实现了PC通过RS-232的方式和松下PLC的通信的目的。着重介绍了松下MEWTOCOL-COM协议的内容,以及MSComm控制的一些常用的事件和属性。     

PC104在微波辐射计数据采集系统中的应用

介绍一种微波辐射计数据采集系统, 由基于Linux操作系统的PC104工控机与基于MCS-51系列的单片机构成. 硬件电路设计以PC104工控机SB-810VE2S为核心, 以MCS-51单片机实现微波辐射计接收数据逻辑控制, 外接存储器件及其他外围电路; 软件设计通过对PC104工控机在Linux操作系统下串口通信编程, 实现了PC104工控机通过串口和MCS-51系列单片机进行通信, 从而构成一个数据采集系统, 并采集了微波辐射计的数据.     

Vb6.0实现PC机与PLC通信(欧姆龙CPM2)

本文对CPM2系列欧姆龙PLC的通信协议进行了详细的介绍,并以VB为开发工具实现了PC机与欧姆龙CP系列PLC的串行通信。     

计算机同单片机串行通信中波特率的确定

介绍PIC系列单片机中带串行通讯模块SCI的芯片与PC机串行数据交换的实现方法,其列举芯片为目前应用较广的PIC16F877,在介绍编程实现方法的同时,给出其硬件接口电路及通信源程序。     

基于ISP技术的软硬件设计

以ATMEL公司生产的AT89S5X系列芯片为例，简要介绍一种通过PC并口实现下载的在系统可编程方法，介绍AT89S51的串行编程的方法和部分协议，并且给出一个AT89S51芯片的ISP下载的软件与硬件应用实例。     

STM32系列单片机脱机批量烧录器的设计与实现

脱机批量烧录器以 STM32F302RB 单片机为主控器,以 SPIflash 作为程序存储器,可以脱离 PC 机独立工作,并支持通过 ISP 下载方式同时对5个 STM32系列单片机进行程序烧录。首先介绍了当前 STM32系列主要采用的下载方式和 STM32F3系列单片机的优点,然后在介绍 STM32系列单片机 ISP 下载模式通信协议的基础上,给出了系统结构框图和程序流程图,最后通过实际使用验证了设计的可行性和烧录效率。     

FX系列PLC与PC的通信研究

介绍了FX系列PLC与PC的通信,从软、硬件角度分别给出了不同的解决方案。指出了编程口通信与计算机链接通信在通信参数配置和通信帧格式上的不同以及软元件地址的计算方法,同时列举了一个完整的PC与PLC通信实例的程序代码。     

液压打包机的PC控制

在液压打包机上采用可编程控制器ＰＣ，简化了电控系统，并使液压打包机故障率减少，易于调整和维修。     

高压真空断路器智能在线监测系统研制及故障诊断

为了提高断路器运行的可靠性,设计了一种基于数字信号处理器(DSP)和LabV IEW的高压真空断路器智能在线监测系统的开发新方案.该系统主要由上位机、下位机和传感器环节等三大部分组成,其中传感器和下位机构成现场监测模块,并安装于断路器本体上.下位机硬件平台以TM S320F2812DSP为核心完成对断路器机械参数、分合闸电流信号和振动信号的采集、处理与显示,同时通过CAN总线将数据送至上位机.上位机管理软件采用LabV IEW软件开发,主要完成对测量数据的存储、显示和分析处理等.测试结果表明,研制开发的高压真空断路器智能在线监测系统能够实时地反映真空断路器机械运行状态,具有人机交互友好、功能齐全和可靠性较高等特点,并且实现了在线监测系统预期的功能.     

I-J epitopes are adaptively acquired by T cells differentiated in the chimaeric condition

I-J has been defined as a locus mapped in the murine major histocompatibility complex (MHC) which encodes serological markers found primarily on the surface of suppressor T cells (TS) and soluble suppressor factors (TSF). Recent studies have, however, revealed that there is no such specialized locus within the MHC at the DNA level. As the existence of I-J determinants at the protein level on functional T cells, T-cell clones and hybridomas has been confirmed by several serological and biochemical studies, this contradiction has raised serious arguments in the immunological community concerning the nature, origin and expression of I-J determinants. We have raised a number of monoclonal antibodies against the polymorphic structure of I-J molecules, and have studied the expression of I-J epitopes on T cells derived from irradiated bone marrow chimaeras in which stem cells of different genotype differentiated into T cells under the foreign host MHC environment. The results, presented here, indicate that I-J epitopes are not primarily determined by the MHC genes of the stem cells themselves, but are adaptively acquired by T cells differentiated in the chimaeric condition according to the environmental MHC phenotype. Thus, the serologically detectable I-J epitopes are found to be associated with inducible T-cell receptors recognizing self class II MHC antigens.     

I-J as an idiotype of the recognition component of antigen-specific suppressor T-cell factor

The I-J determinant of membrane glycoprotein is known to be expressed exclusively on suppressor T cells (TS), which have a crucial role in the regulation of immune responses. I-J also comprises part of the soluble factor (TSF) with suppressor activity which is secreted from TS. Gene-mapping experiments have indicated that the I-J gene lies between the I-A and I-E subregions of the mouse major histocompatibility complex (MHC) and is defined by the H-2 congeneic pair, that is, B10.A(3R) and B10.A(5R). In fact, antibodies raised in the reciprocal combinations of B10.A(3R) and B10.A(5R) define the I-Jb and I-Jk alleles, and are able to detect the I-J determinants on TS and TSF. Biochemical and functional analyses, using I-J-positive TS clones and hybridomas, have demonstrated that monoclonal anti-I-J antibodies precipitate I-Jk or I-Jb with a relative molecular mass of 25,000-28,000 (25-28K) and that the I-J+ molecule mediates the restriction specificity of TSF in association with an antigen-binding protein (45K). However, molecular genetic studies on the I-J gene reveal no genetic difference between B10.A(3R) and B10.A(5R) and also that there is no room to accommodate a gene encoding I-J in the expected I region. These discrepancies between the molecular genetic and serological/functional data require explanation. Here we demonstrate that TS and TSF expressing I-J of the host type were produced by fully allogeneic bone marrow cells of donor origin in chimaeric mice, when the chimaeras received the host antigen-presenting cells (APC) at the time of immunization. The results show that APC are necessary for the activation and clonal expansion of TS and also support the notion that I-J is an idiotypic determinant of the recognition component of TS and TSF.     

CV条外透明纸包装机送纸滚轮改进及应用

通过研究分析GDX2包装机组中CV条外透明纸包装机的透明纸输送和包装原理,重新计算和设计了透明纸扇形送纸滚轮的尺寸,利用原CV条透纸扇形送纸滚轮进行了适当改进,并进行了一系列相应同步关系的调整.在不改变条烟外透明薄膜纸包装效果的基础上,缩短了单张透明纸的长度,既使透明薄膜纸的包裹符合工艺要求,又达到了节约了透明薄膜包装材料的目的.     

e-learning支持SCORM规范的实现

课件内容的共享是保证e learning提供迅速、稳定及互通的在线学习的重要基础 .CloverSuitee learning通过支持SCORM 1.2实现支持学习资源的共享和系统的互操作性 ,支持SCORM格式的课程导出和导入 ,支持对SCORM格式导入课程的跟踪和浏览 .经测试 ,系统通过了ADL发布的SCORM一致性测试套件基本测试 (学习管理系统LMS RTE1级 ,内容包装ADLCP PIF1级 ) .     

A molecular map of the immune response region from the major histocompatibility complex of the mouse

A stretch of 200 kilobases (kb) of DNA from the I region of the mouse major histocompatibility complex has been cloned and characterized. It contains the genes for the biochemically defined class II proteins E alpha, E beta and A beta. DNA blot analyses suggest that the I region may contain only 6-8 class II genes. Correlation of our molecular map with the genetic map of the I region confines two of the five I subregions, I-J and I-B, to less than 3.4 kb of DNA at the 3' end of the E beta gene where a hotspot for recombination has been observed. Indeed, the I-A and I-E subregions may be contiguous. If so, the I-B and I-J subregions are not encoded in the I region between the I-A and I-E subregions.     

工作站故障排除分析

该文主要从工作站故障点链、工作站到网络的连接失败、PC机插卡、主板和BIOS故障、操作系统及软件故障、用户失误等方面对工作站故障进行了分析,使用户了解一般工作站的故障的解决办法。     

基于VB的计算机与智能仪器串口通信

VB软件在编制测控程序方面应用广泛.本文阐述了串口通信的方法及其在VB中实现通信的途径,讨论了智能仪器的串口通信特点和格式,并在VB环境下编制了一真空计与计算机的串口通信程序.     

相变储能型太阳能真空集热管运行特性研究

为了解相变储能型太阳能真空集热管的运行情况,对不同工况下单根真空管的运行情况以及三根真空管串联运行的情况进行实验研究,实验主要分为吸热和放热两个阶段.单根真空管运行的研究结果表明,吸热阶段,晴天和多云工况下,日平均集热效率能够达到30％～45％;阴天工况下的日平均集热效率很低,只有6％左右,且在吸热过程中由于U型铜管中...