C51嵌套汇编子程序在阻抗测试仪研制中的应用

C51嵌套汇编子程序，充分发挥了两种语言自的优势，介绍了C51调用汇编子程序的接品规则，并通过阻抗测试仪程序开发的例子予以详细说明。     

A low cost calibration conditioner for dynamic strain gauge measurements

A conditioner for dynamic strain measurements that allows for a series of calibration signals with periodic and predefined time occurrence, during the whole period in which the measurements have to be carried out, is presented in this work. The calibration signals, having suitable size ratios between them, allow one to evaluate the linearity of the entire measurement chain.     

Procedures for analysis of strain transfer in the acetabular region in vitro

The failure of acetabular cups via loosening, migration or fracture is partially related to the stress distribution existing in the acetabular region. The complexity of the investigation of these stresses demands the application of a variety of model testing techniques involving combined embedded strain gauging, finite element analysis, transmission and reflective photoelasticity and crack propagation studies. The application of these procedures are described and the difficulties of obtaining representative loadings and restraints are commented upon.     

Optical analysis of crack tip stress fields: a comparative study

Four optical techniques for evaluating stress intensity factors in opaque specimens are described in outline, and compared for both an artificial crack and a fatigue crack. The results are compared to a standard solution for the geometry considered. All the techniques gave acceptable results over a range of stress levels and crack lengths. The methods of caustics and strain gauges were less good, whilst photoelasticity gave consistent results over a wide range of stress levels. Comments on the ease of application and the resource implications are also made in order to assist practitioners.     

Development of temperature compensated high elongation resistance strain gauges for use up to 250°C

The paper describes the development and evaluation of temperature compensated high elongation resistance strain gauges for use from room temperature to 250°C. These gauges could be temperature-compensated on steels with coefficient of thermal expansion α = 11 ppm/°C. Thermal output within 250°C was about 1 μm/m/°C and maximum standard deviation of 5 gauges was 34 μm/m. Strain limit was > 4% at room temperature and at 250°C. Gauge factors of different strain ranges at R.T. and at 250°C are tabulated. Some applications are stated.     

Measuring the load eccentricity in helical compression springs

An experimental device able to detect the load eccentricity in helical compression springs is described. The theory underlying the resolution of measured bending strains of the apparatus into effective load eccentricity is discussed. Laboratory results are offered for heavy duty springs and compared to theoretical estimates retrieved from the literature.     

嵌入式装置图形化编程工具软件设计与应用

嵌入式图形编程工具软件采用组件化设计,以图形化、层次化、面向对象的编程方式组织整个装置的程序结构。该软件主要包括符号库编辑组件、资源管理器组件、图形编辑组件、代码生成组件、编译链接等组件。介绍了相关组件的设计要点,提出了基于可扩展属性的符号库建模方法、类lEC61131－3标准的层次结构数据模型、基于MVC模型的图形编辑器、基于改进AOV网拓扑排序的代码生成方法、基于可配置模板的Makefile形成方法。基于该软件开发的程序已经在电力系统保护控制装置中应用,实践表明图形化编程工具软件能形成高效紧凑的代码,符合程序运行效率的要求,提高了装置开发集成效率。     

面向安全生产综合监管系统的工作流引擎

针对安全生产监管系统中关键业务应用的开发离不开工作流技术支持的特点,通过对安全生产监管领域中关键业务的实际开发需求的分析,引进了工作流技术,设计并实现了一个轻量级嵌入式工作流引擎;本文首先对安全生产综合监管系统整体架构进行分析,然后提出该工作流引擎的设计方案,并详细阐述了引擎设计的关键环节;最后把此工作流引擎应用到安全生产综合监管系统中,不仅显著地缩短关键业务的开发周期,同时也规范了各种关键业务处理流程。     

A power and data front-end IC for biomedical monitoring systems

To enable the evolution towards electronically assisted healthcare, future medical implants require sensors and processing circuitry to inform patient and doctor on the rehabilitation status. An important branch of systems are those where implant strain is monitored through strain gauges. Since batteries inside the human body are avoided as much as possible, a transcutaneous power link is used to wirelessly power the implant. The same RF link provides an elegant way of establishing bi-directional data communication between the external base station and the medical device. This paper describes a front-end IC that manages both power reception and bi-directional data communication. It has a clock generation circuit on board to drive additional digital processing circuits. A new architecture that uses a current driven data demodulation principle is introduced. It is able to detect an AM signal with modulation depth of a mere 4%, which is better than recent similar systems in the field. The IC is fabricated in a solid 0.35 μm HVCMOS technology and consumes only 0.56 mA.     

基于小波变换的音频数字水印方法

数字水印是为了解决保护知识产权等相关问题而发展出来的一种技术。该文针对音频上的数字水印,提出以小波封包分频方式,按照人耳声学模型,将音频信号由滤波器群组分成29个次频带,从而找出最小临界值,此值作为嵌入数字水印时小波系数的依据。并且使用区域分频来过滤不适合嵌入水印的频率,区域,将数字水印嵌入不易改变极性的频率区域,提高了的数字水印的鲁棒性。