FIR数字滤波器在振动测试系统中的应用

使用FIR数字滤波原理设计通带范围为 0～ 10Hz的数字滤波器 ,并采用Blackman窗函数分别以 199,3 99,5 99,799,1199阶对振动试验机采集的数据做滤波处理。结果表明 ,当阶数大于 3 99时 ,滤波器可有效地滤除干扰噪声 ,滤波后的信号曲线可很容易地确定出不平衡量幅度和相位     

MOXA嵌入式系统在变电站综合自动化系统中的应用

介绍基于MOXA嵌入式系统构建以太网的变电站综合自动化系统,给出网络实现方案及其功能特点。     

浅谈嵌入式系统

从集成电路微型计算机的发展入手,对嵌入式系统的发展、定义、特征、组成等方面展开阐述。     

嵌入式超声测井数据采集系统

利用超声波对井壁进行横向扫描,根据回波信号对井壁各层情况进行分析,从而能很好地采集到井壁的各项数据。本文以PXA270处理器作为硬件开发平台,对超声波发生器产生的模拟井下信号经回波后进行采集,调理放大后的模拟信号经A/D转换后送至存储器单元,再被绘图程序调用进行实时波形显示。该超声波测井作为测井的一种重要方法得到了广泛的应用。     

嵌入式C语言在系统开发中的代码优化

C语言是嵌入式系统开发中常用的一种程序设计语言．本文结合嵌入式系统的特点,从编程规范、存储器分配和算法优化三个方面,阐述了C语言在嵌入式软件开发中的代码优化方法。     

嵌入式系统IAP在GPRS远程集中抄表系统中的应用

介绍IAP（在应用编程）方法及其相关应用,以及将IAP应用于嵌入式系统设备软件远程升级的现实意义;结合某地区远程集中抄表系统,着重阐述采用GPRS无线通信进行远程软件升级的思想和实现方法,以及应用中应注意的一些关键技术,并讨论了提高GPRS远程升级速度和可靠性的一些措施。     

MPS5000B立磨系统振动测试分析

我公司MPS5000B生料立磨曾在生产中出现过振动较大的情况,无法满足生产要求。为了确保立磨及传动系统长期安全运行,满足生产要求,对立磨系统的状态进行了跟踪监测,以对故障进行正确诊断和预测。本文对此作一总结。     

基于S3C2410的嵌入式弧焊电源测试平台设计

基于三星公司的S3C2410处理器设计了一款弧焊电源测试平台,利用该平台实现对弧焊电源电参数的测量,评估被测弧焊电源的质量和产品性能。该系统适合交、直流弧焊电源测试,可以进行静态工作点的测试和电流、电压及功率等电参数的测量。     

空气预热器振动测试分析

在研究空气预热器振动机理的基础上,利用双通道数据采集器对某化工厂管式空气预热器进行振动测试,分析其振动数据和频谱特征,结果表明管箱内声驻波是引起振动的主要原因,并提出消振措施,为空气预热器的安全运行提供了一定的技术支持。     

嵌入式技术应用研究

嵌入式系统的一种流行的定义为以应用为中心,以计算机技术为基础,软件硬件可裁剪,适应系统对功能、实时性、可靠性、成本、体积、功耗严格要求的专用计算机系统或称为非智能电子设备。嵌入式设计技术和芯片技术也经历着一次又一次的革新。在当今数字信息技术和网络技术高速发展的时代,嵌入式系统已经被广泛应用于移动计算平台、掌上计算机、信息家电数字电视、机顶盒、网络设备、无线通信设备手机、股票接收设备、工业商业控制智能工控设备、电子商务平台、航空航天以及军事应用等诸多领域。     

V-notched rail shear test applied to geopolymer composites

This work presents a systematic study of the shear properties of a potassium-based geopolymer reinforced with distinct types of fibers. Chopped basalt reinforcements in lengths from 3 mm up to 50 mm and 13 μm in diameter were compared with thicker 20-mm length, basalt mini bars, sand-coated basalt mini rods, and steel fibers. The samples were tested under a V-notched rail shear tests (ASTM D7078), coupled with optical measurements, namely, digital image correlation, allowing a novel study of their crack patterns and failure modes under shear loading. In general, the use of chopped fibers resulted in shear strengths of up to 9 MPa and shear moduli of 4.3 GPa, with no significant variation with fiber length increments, neither in shear stress nor strain at peak load (0.1%). Mini bars and steel fiber reinforcements resulted in slightly lower shear stresses of 7.1 and 8.4 MPa, respectively. They exhibited greater strain values at peak loads, up to 2.1% which were attributed to fiber-matrix enhanced adhesions, thereby allowing gradual debonding and increased ductility. This effect was also recorded for mini rods, but at much lower strength levels, which did not contribute to their multiple cracking capacities. The alignment of the mini rods in 45° directions resulted in a 50% increase in shear stress, showing the feasibility of tailoring the manufacturing process to attend to distinct demands.     

Double-sensor conductivity probe applied in a flotation system

This study proposed a new approach for measuring bubble size distribution, bubble mean diameter, Sauter mean bubble diameter, and gas holdup using a double-sensor conductivity probe in an air/water two-phase system bubble column. The results for the two-phase system were compared and calibrated using analyses from bubble images taken by a digital camera from the side of the column wall. Good agreement was observed between the two techniques. The same double-sensor conductivity was used in an air/water/solids three-phase system. The conductivity probe captured the change in bubble dynamic behaviour inside the pulp phase; however, the presence of the solids made it more challenging to measure. As a result, the VisioFroth commercial package, using images taken from the top of the froth layer, could be used in conjunction with the double-sensor conductivity probe to show the dynamic evolution of mineralized bubbles from the pulp zone to the froth zone in a flotation process.     

计算机控制技术在轮胎硫化系统中的应用

采用中控PLC、智能温控器及压力仪表等替代原三针记录仪，实现外温的闭环控制和记录；利用电动机变频调速技术，使硫化用水的压力恒定，并取消一次供水泵，降低电能消耗；取消硫化机冷凝水排放的疏水阀，实现由温度和定时控制相结合的冷凝水自动排放方式，节约蒸汽用量；在硫化机上加装轮胎胎号输入装置，使轮胎硫化过程参数的历史查询更为方便。     

Colorimetric principles applied to designing test kits for medical diagnosis

Many diseases involve the introduction into the body of highly specific foreign substances (antigens) to which the body responds by producing complementary antibodies. A test method has been developed whereby several different antigens can be detected simultaneously. One drop of fluid (e.g., blood serum, urine, saliva, etc.) from the patient is mixed with one drop of reagent on a card. Within two minutes a colour change takes place, each colour developed being diagnostic of a particular antigen. This paper describes the test and shows how colorimetric methods were used to optimise its performance, standardise the materials used, and determine the requirements for proposed further development.     

The oxidative inducation test applied to medical PVC and other polymers

We have examined the applicability of this simple and effective test to polymer systems widely used in the medical industry. First, it was found that not every polymer examined exhibited a distinct onset of autocatalytic oxidation detectable by DSC. However, for cases where distinct onsets are found, powerful insights can be obtained. These included activation energy of the degradation, thermal oxidative shelf life prediction, and correlation, with product performances. Actual examples are presented to illustrate the utility of the test.     

多功能爆炸压力测试系统的设计研究

设计出一套多功能爆炸压力测试系统。该系统可分别对液体蒸气、粉尘、可燃气体与空气混合后的爆炸压力进行测试,也可通过安装示波器、光敏二极管、高速摄影仪等对爆炸过程的其他参数进行测试,为进一步丰富、完善爆炸理论和爆炸试验提供了可靠的数据,也为安全工程专业的爆炸灾害防护提供了一定的依据。     

强化传热技术在挤出机温控系统中的应用

首先详细阐述了温度控制在挤出加工过程中的重要性，然后对挤出机的传热过程进行了系统的分析，由此确定了强化传热技术在挤出机温控系统中的切入点，然后对当前几种强化传热结构机筒的换热能力进行综合评估比较，本项评估比较以精确数值计算为蓝本，为新型机筒流道结构设计提供了很强的参考价值。     

Oxidation of phytosterols in a test food system

The oxidative stability of phytosterols in canola, coconut, peanut, and soybean oils was examined under simulated frying conditions of 100, 150, and 180°C for 20 h. The degree of oxidative decomposition was assessed by the loss of phytosterols, accumulation of phytosterol oxides, and the change in fatty acid profiles. The phytosterol oxides produced in the oils were identified using mass spectroscopy. Oils with higher levels of polyunsaturated fatty acids showed greater amounts of sterol loss; however, the sterol loss was less complete than in the more saturated oils. A greater variety of sterol oxides was observed at the lower temperatures of 100 and 150°C compared to 180°C. This study demonstrates that under conditions similar to frying, there is a loss of phytosterols and polyunsaturated fatty acids. The accumulation of phytosterol oxides may be temperature-limited because of further break-down into products not measurable by typical gas chromatography-mass spectrometry techniques.     

A program system applied to modeling physicochemical processes in forming chemical fibers

A visual modeling system has been developed in which the mathematical models for molding are represented as sets of linked physicochemical phenomena. If the molding is supported by input data, the model enables one to determine new technological parameters when there is a change in the range of fibers or there are changes in some of the technological parameters. The models represent a program for setting up new processes for forming chemical fibers, in which one states a set of necessary data providing viability and filling the model database. These models can be used in devising systems for automating chemical fiber shaping. Translated from Khimicheskie Volokna, No. 4, pp. 34–38, July–August, 2008.     

PLC和变频器在胎面自动裁断系统中的应用

详细介绍了胎面裁断系统的工作过程，以及控制变量的确定、主要元件的选取和部分控制回路的设计图。