LPC2131基于CPLD的CAN接口设计

引言 Philips公司的LPC2131是基于ARM7TDMI—S的高性能32位RISC微控制器。它具有ARM处理器的所有优点——低功耗、高性能和较为丰富的片上资源,但LPC2131内部没有集成CAN控制器,而无法利用CAN总线来进行通信。为了使得LPC2131能够利用CAN总线进行通信,可以通过外部扩展来实现其功能。目前,比较普通的方法是在LPC2131的外部采用CAN控制器设计CAN总线接口。LPC2131与CAN控制器的接口电路如图1所示。     

配料秤信号传输方式的比较与应用

介绍6种配料秤信号传输方式,并进行比较,提出传统配料秤改造和新上配料秤时的推荐方案.     

基于ADAM5510的新型失重秤设计

通过对老式失重秤工作原理的介绍,分析了老式失重秤在流量测量过程中的误差来源,提出一种基于ADAM5510为控制器的新型失重秤的方法。并阐述了其工作原理及控制方案。实践证明,对于提高失重秤的称重精度和计量精度效果明显。     

电子负秤原理及其在混凝土自动配料设备中的应用

阐述了电子负秤的基本原理,对比分析了正秤和负秤在混凝土配料计量方面的性能。介绍了一种新颖的计算机控制的混凝土自动配料机。该配料机首次采用电子负秤这一独特的计量原理,结构设计简单、合理,具有较高的性能价格比。最后探讨了消除或减少系统配料误差的几种方法。     

基于LPC2136微控制器的DTMF编码器设计

本文通过对临界稳定双极点滤波器的分析,得出了可程序实现的数字振荡器的递推公式,并给出了由此建构基于LPC2131微控制器的DTMF编码器的原理、方法和相应的程序设计流程。     

一秤多盘（斗）电子配料秤及其应用

简要介绍了一种电子配料秤的工作原理，硬件实施及该系列配料秤的主要特点、技术性能及其应用情况。重点讨论了如何采用一个A/D转换器实现一秤多盘（斗）的功能。     

攀钢烧结配料计算机过程控制系统

介绍以霍尼韦尔 Ｓ９０００ 小型集散系统构成计算机过程控制系统实现烧结配料的自动控制,并阐述了烧结配料的特点及其对配料秤的要求和系统软、硬件的设计过程。实用结果表明：控制系统稳定、可靠,在应用中收到良好的控制效果。     

新一代配料控制器及其应用

9215单秤自动配料控制器集配料控制和PLC功能为一体,具有墙挂式和面板式两种基本结构,应用于模拟传感器及数字传感器秤。 9215可控制16料双速自动配料。零点和目标误差检查、提前量、自动提前量调整和自动补料等配料控制技术均在9215中实现。下面主要介绍面板式9215配料控制器特点及其应用。一、面板式9215配料控制器工业配料系统的核心是配料控制器,由它控制原始成分的称重和配料。托利多9215面板式配料控制器由8142/8510称重显示仪、9215控制器、手动控制器、Smart Link I/O板组成,如图1所示。     

多线程微机控制配料系统软件的设计与实现

讨论了在微机控制配料系统中,双秤配料系统的工作原理与计算机控制原理,并给出了软件设计流程图及实现多线程控制的程序代码.该方法目前已经应用到饲料加工生产中,对提高生产速度和生产率起到了至关重要的作用.     

核子秤变频调速配料系统

目前国内水泥厂生熟料配料普遍采用电子皮带秤和示重秤配料，这两种配料方式有如下缺点： ①电子秤使用压力传感器，由于配料现场灰尘大，压力传感器容易进灰，导致性能降低甚至损坏；由于存在机械振动或人为振动，皮带机碰撞压力传感器，易导致压力传感器损坏。 ②示重秤产量低，配料均匀性差。 ③由于缺少必要的过流、过压、缺相保护设备，经常烧毁电机。 ④基于以上三点，电子秤和示重秤动态配料精度低、产品合格率低、设备利用率低、故障率高、设备维护费用高。 基于以上原因，为了提高产品质量，提高设备利用率，降低成本，水泥厂生熟…     

Estimating the Attraction Domain for the Boost Inverter

This work presents an approach for estimating the domain of attraction for polynomial systems with state and control‐signal constraints, including saturation. In many problems, it is possible to derive global stability properties for such systems, neglecting constraints. Consideration of the constraints usually makes the problem much more complicated. In this paper, the stability analysis performed for the unconstrained case is used for the problem as a whole. For application of the method, there are powerful computational tools that can be employed in cases of polynomial systems. The technique is not only valid for the analysis of equilibrium points, but also for other attractors, such as limit cycles. As examples, the domain of attraction for given control laws is estimated for both a nonlinear DC‐DC boost converter and for a boost inverter.     

Meme Media for Clipping and Combining Web Resources

The publication and reuse of intellectual resources using the Web technologies provide no support for us to clip out any portion of Web pages, to combine them together for their local reuse, nor to publish the newly composed object as a new Web page for its reuse by other people. This paper shows how the meme-media architecture is applied to the Web to provide such support for us. This makes the Web work as a shared repository not only for publishing intellectual resources, but also for their collaborative reediting. We will propose a general framework for clipping arbitrary Web contents as live objects, for defining IO ports on such a clip, and for the recombination and linkage of such clips based on both the original and some user-defined relationships among them. In our previous works, we proposed two separate frameworks for these three purposes; one works for the first two, and the other for the last. Here we will propose a unified framework for these three purposes, as well as its detailed internal mechanisms. Then we show how it can be easily applied to various legacy Web applications to develop innovative services.     

A Probabilistic Analysis of Multiple-drug Testing Procedures in Sports Doping Control

Athletes engaged in competition, particularly those involved in international competitions such as the Olympics, are increasingly being tested for a greater variety of banned substances; it is not unusual for tests to be conducted for 100 drugs and another 400 as metabolites. Previous studies related to the accuracy of drug testing processes have failed to properly consider the effects of testing for more than one drug. In order to identify appropriate indicators for the multiple-drug case, probability theory and accuracy concepts applicable to testing for multiple drugs are developed and applied to illustrative data. The probability that a drug-free individual will test positive for drug use is shown to be much higher than indicated by previous studies, and it is shown that an increase in the number of drugs tested for yields an approximately proportionate increase in the probability that a positive test result is erroneous. Therefore, while testing for one drug may result in a comfortably low rate of false accusations of drug use, testing for multiple drugs may well result in an unacceptably high rate. Finally, a set of empirical measures is suggested for use in cases of tests for multiple drugs; the measures will provide for comparability among laboratory proficiency studies.     

水利系统干部人事档案数字信息化建设探索与实践

干部档案数字信息化建设是干部档案工作在信息化时代的必由之路,是提高干部信息管理和利用水平的必然要求。在阐述档案数字信息化概念的基础上,以南京水利科学研究院干部人事档案数字信息化建设为实例,对水利干部人事档案数字信息化建设进行有益探索,提出水利系统干部人事档案数字信息化系统建设的要素确定、基本程序及主要环节,具有实用性和可操作性。     

一种分布动态网络安全系统框架

网络是人类社会全新的活动空间。这个活动空间必须符合人类社会活动的规则。信息安全是其中最重要的问题。安全问题不是某个使用网络部门的事,而是需要全社会合力解决的问题。本文从入侵检测信息的标准化入手,提出了一个分布动态网络安全系统框架结构。探讨了分布动态网络安全系统框架的层次结构、通讯方式和协议,通过分布动态网络安全系统框架解决攻击源定位、攻击响应及重要应用系统的防护等问题。     

基于物联网技术的智能家居椅控制系统设计

针对国内外智能家居椅控制系统二次开发难度大、接口兼容性差等问题,基于物联网技术,对现有智能家居椅控制系统进行了二次开发.采用STM32控制器对智能家居椅控制系统的输入输出接口进行扩展,引入压力传感器、S型称重传感器、光电探测器对家居椅各个执行机构进行监测,开发了基于Java语言的微信客户端应用(APP)程序,实现了智能...     

Compact disc standards: an introductory overview

The success of the compact disc (CD) as a storage medium for digital audio has, over the last ten years, resulted in a number of initiatives to use the CD for other applications as well, e.g., as read-only memory for computers, as a storage medium for audio-visual material for multimedia applications, and as a storage medium for photographs. Each of these applications poses additional requirements on how the corresponding information is stored and retrieved, resulting in a range of different CD standards. The functional specifications of these standards are each given a specific color for ease of reference: the Red Book for CD-DA, the Yellow Book for CD-ROM, the Green Book for CD-I, etc. This paper aims at giving an overview of the various CD standards by explaining what is specified in each of the colored books and by indicating how they relate to one another.     

The most economic setting for a uniformly shifting process

A method for finding the optimal setting for a uniformly-shifting process mean is developed and an algorithm for solution (suitable for microcomputer implementation) is presented. A determination of the number of parts to be made before resetting, and the level to which the process is to be reset is made given costs for improperly sized parts and for process resetting.     

A stress-strength interference model for predicting CTD probabilities

A model for predicting the incidence rate of carpal tunnel syndrome (CTS) for a given job, was developed using known biomechanical data, mechanical properties of human tendons and reliability engineering techniques to simplify the problem. In addition, time-dependent stress-strength interference theory was used to quantify the stress on the tendons during a job cycle, based on wrist position and grip strength and to estimate the tendon failure rate (or CTS incidence) for a given job. Higher failure probabilities were predicted for greater wrist deviations, for higher grasp forces, for females as compared to males, for wrist extension as compared to wrist flexion, and for two-fingered pinches as compared to four-fingered grasps. The predictions closely matched previously reported CTS incidence rates for a poultry thigh boning task.     

An omni-directional mobile millimeter-sized microrobot with 3-mm electromagnetic micromotors for a micro-factory

This paper presents an omni-directional mobile microrobot for micro-assembly in a micro-factory. A novel structure is designed for omni-directional movement with three normal wheels. The millimeter-sized microrobot is actuated by four electromagnetic micromotors whose size is 3.1 mm × 3.1 mm × 1.4 mm. Three of the micromotors are for translation and the other one is for steering. The micromotor rotors are designed as the wheels to reduce the microrobot volume. A piezoelectric micro-gripper is fabricated for grasping micro-parts. The corresponding kinematics matrix is analyzed to prove the omni-directional mobility. A control system composed of two CCD cameras, a host computer and circuit board is designed. The macro camera is for a global view and the micro camera is for local supervision. Unique location methods are proposed for different scenarios. A microstep control approach for the micromotors is presented to satisfy the requirement of high positioning accuracy. The experiment demonstrates the mobility of the microrobot and the validity of the control system.