串口通信在CVD金刚石膜生长系统中的应用

本文主要介绍在CVD金刚石膜生长系统中如何利用MSComm控件实现串口通信，并给出了以Delphi开发的实例程序。此外阐述了以分时循环方式实现单通道多信号采集的原理和实现方案。     

电阻点焊工艺参数实时监测系统

研究了基于PC机的电阻点焊工艺参数实时监测系统.基于Windows系统,采用VC语言研究开发了系统的数据采集及分析软件,实现了点焊工艺参数的高精度测量.该系统适合于各种交、直流点焊设备主要工艺参数,即焊接电流,电极压力等参数的实时监测,对监测数据进行实时分析并进行数据库永久存储.     

基于ARM和uClinux的泵性能监测系统的开发

泵的性能对系统有重要影响,为了对泵的各项参数进行监测,利用ARM和uClinux成功地开发了泵性能参数监测系统.该系统完成对泵性能参数的监测和数据的存储.整个系统采用数据采集板加上位机的开发模式.数据采集板采用单片机完成信号的分类与采集.上位机采用基于ARM和uClinux的嵌入式系统完成数据的接收,显示和存储.数据采集板和上位机之间采用RS232进行通信.目前,该系统已经应用于对潜艇上的泵的性能的监测.该系统很好地实现了对泵的性能的监测,通过对监测得到的泵的运行参数的分析,可以对泵进行故障预测.     

离网型风光互补发电数据采集系统的实现

为了解决离网型小容量风光互补发电系统在设计过程中缺乏必要的运行参考数据的问题,设计了一套运行参数数据采集系统.该系统主要由太阳能电池板、直流风力发电机、上位机、数传电台以及ADAM-5000数据采集模块等组成.利用Visual Basic 6.0开发上位程序,通过MSComm控件接收并记录运行参数以及自动计算气象等参数.该系统还具有报表和曲线绘制功能.所采集的运行参数为风光互补发电系统的设计、风光互补的匹配和优化计算、控制器开发等项目的开展提供了依据.     

人造金刚石生产过程Fuzzy—PID功率控制系统

该文介绍了人造金刚石生产过程数据采集及Fuzzy-PID功率控制系统研制,系统由基于Rs485总线的嵌入式数据采集器/控制器和PC计算机组成。嵌入式数据采集/控制器由51单片机实现,采用C51语言编写数据处理程序;PC机作为监控主机,采用图形化语言LABVIEW开发上位机软件,并具有显示温度、功率等参数曲线、数据表格和存盘打印等功能;控制上采用模糊PID控制算法实现对金刚石压机系统功率的连续精确控制。实践表明,系统达到了设计要求功能和技术指标,取得比较好的测量与控制效果。     

环境监测系统通信协议测试与分析

环境监测系统是当前物联网在环境领域的一个重要应用.现场数据采集仪对污染排放点进行实时监测和采集,通过各种通信网络实时发送到后端服务器进行处理.该系统从底层逐级向上可分为现场数据采集仪(现场机)、通信网络及监控中心(上位机)三层组成.通过测试工具SilkPerformer模拟现场机与上位机之间指令交互,验证通信协议符合性...     

热轧机组运行状态非线性相关约束分析

热轧带钢生产线各机架轧制力、板宽、板厚控制系统, 须根据轧制工艺计算设定参数. 但在实际运行中, 由于各种干扰因素的影响, 往往偏离系统设定值, 本文根据分布式数据采集系统的基本数据库, 通过轧制工艺参数约束方程, 运用数据融合方法, 对实际轧机运行状态作出综合分析, 为进一步优化轧机运行参数提供重要参考.     

Windows98下远程数据采集系统设计

在数据采集系统中,常利用PC机串行口通过串行通信,实现远程数据采集.介绍了某一远程数据采集系统的设计过程、方法以及该系统的硬件构成,并利用Visual C++ 6.0在Windows98环境下,编写了相应的通信及控制程序.     

风光互补发电数据采集监测系统的设计

针对风光互补发电系统随环境影响大、系统稳定性差、不便于维护等特点,设计了风光互补发电数据采集监测系统。介绍了监测系统的结构和工作原理,分析了数据采集硬件设计、数据的发送与保存以及上位机监测软件的具体实现方法。该系统可以将风光互补发电系统相关的环境参数和电参数通过三种方式进行保存和发送,并且通过上位机直观的显示出来。经测试,该系统能够稳定的对风光互补发电系统进行监测。     

基于LabView的电力谐波检测系统的设计与实现

设计实现了基于虚拟仪器技术的电力谐波检测系统,该系统以80C196kc作为数据采集电路的核心部件,通过RS232串行口把采集到的数据发送给PC机,由PC端基于LabView软件编程实现各次谐波分量的有效值及相关参数的计算、电压电流波形和各参数的显示、控制等功能.实验结果表明该系统检测方便,精度较高,运行稳定可靠.     

金刚石薄膜的制备研究综述

金刚石薄膜具有优异的物理化学性质,在耐磨涂层、生物医学、薄膜微传感器、微机电系统等诸多领域有着广阔的应用前景.文章综述了近年来在金刚石薄膜领域研究的最新进展,着重介绍了目前主流的金刚石薄膜制备方法及优缺点,阐述了薄膜的生长机理以及提高金刚石薄膜沉积速率和质量的技术方法,为该领域的研究人员提供参考.     

Effects of microstructure of films on CVD diamond X-ray detectors

Although the unique properties of chemical vapor deposition (CVD) diamond films have made it a candidate material for radiation detectors, the polycrystalline nature of the films has severely limited the development of CVD diamond detectors. In this work, three CVD diamond films with different microstructure were grown by using a hot-filament chemical vapor deposition (HFCVD) technique and were fabricated as CVD diamond detectors. The electric contact is good ohmic for bias voltage up to 150 V. 5.9 keV ⁵⁵Fe X-ray was used to measure the photocurrent and the pulse height distribution (PHD). For the detector based on the best quality film, the dark-current of 16.0 nA and the net photocurrent of 15.9 nA are obtained at an electric field of 50 kV cm⁻¹. The PHD peak is well separated from the noise pedestal, indicating a high counting efficiency and a low detection limit.     

衬底温度对单晶金刚石同质外延生长的 影响规律研究

文章采用微波等离子体化学气相沉积法,以单晶金刚石籽晶为衬底进行金刚石外延生长,通过拉曼光谱、扫描电子显微镜及光学显微镜等多种表征测试手段,系统地研究了衬底温度对单晶金刚石同质外延生长的影响机理.研究结果表明,衬底温度是影响同质外延单晶金刚石生长速率、生长模式和生长缺陷的重要因素:在一定温度范围内,单晶金刚石的生长速率随衬底温度的升高而增加,与此同时,金刚石的生长模式也由丘状生长转变为台阶生长.当单晶金刚石的生长厚度超过1 mm时,较高的衬底温度容易导致沉积层边缘部分产生孪晶等缺陷.拉曼光谱表征结果显示,微波等离子体化学气相法沉积的单晶金刚石质量优于传统的高温高压法.     

The microstructure of CVD diamond for high-density thermal inkjet

The microstructure for high-density thermal inkjet (TIJ) is proposed to overcome the defect due to the limit of the nozzle density in conventional TIJs. To bring high-density TIJ, the heat transfer of diamonds by means of placing heaters on sidewall of ink inlet is used in order to minimize the area occupied by the heaters. In addition, manifold, inlet, pressure chamber and nozzle concerning the flow of ink are placed in-line. To demonstrate feasibility, TIJ for bubble visualization test is designed and fabricated. Diamond is deposited on the sidewall of inlet with Hot Filament CVD (HFCVD). The trench filling method and the side deposition method are executed for the vertical sidewall of diamond. To solve the problem for direct CVD deposition on Pt layer, Ta film is utilized as a passivation layer in the fabrication processing. The generated bubble confirms the possibility of the bubble formation by heat transfer of diamond.This work was supported by the Research Institute for Applied Science and Technology, Sogang University.     

Realisation and characterisation of mass-based diamond micro-transducers working in dynamic mode

We report on novel MEMS micro-transducers made of diamond and targeted for bio-sensing applications. To overcome the non-straightforward micromachining of diamond, we developed a bottom up process for the fabrication of synthetic diamond micro-structures involving the patterned growth of diamond using the CVD (chemical vapour deposition) technique, inside micro-machined silicon moulds. Here typical resonant MEMS structures including cantilevers fabricated using this method were characterized by measuring their first mode resonance (frequency and Q-factor) by Doppler laser interferometry. The experimental data matched the simulation data. Data from bare diamond cantilevers and from diamond cantilevers with actuation gold track on the surface were compared and showed a significant decrease in the resonant frequency in the presence of gold tracks. Nevertheless, comparisons with equivalent silicon structures demonstrated the superior performances of diamond cantilevers: the resonance frequencies were twice higher and the Q-factors 2.5 times higher for the diamond transducers. Diamond cantilevers sensitivity were measured using PMMA deposition and values as high as 227.4 Hz ng⁻¹ were found. It was shown that diamond mass sensitivity values are typically two times higher than identical silicon devices. Finally, the limit of detection (LOD) of diamond cantilevers was found experimentally to be as low as 0.86 pg using our set up. This is suitable for many bio-sensing applications.     

Fabrication and micromechanical characterization of polycrystalline diamond microcantilevers

The exceptional chemical, mechanical and thermal properties of diamond make this material the ideal choice for resonant MEMS. Micro-cantilevers designed for biochemical applications have been fabricated using CVD diamond. In this work, the mechanical properties of these cantilevers were investigated by two different techniques: bending test using a Contact Surface Profilometer and resonant test, using a Laser Doppler Vibrometer. The Young’s Modulus of diamond thin film was estimated by these two tests. For the resonance test, the estimated values are comprised between 930 and 1300 GPa while bending test gives values between 950 and 1030 GPa. The load–displacement characteristics and the fracture point (or ultimate stress) have also been investigated.     

Role of the film texturing on the response of particle detectors based on CVD diamond

 Recent improvements in the quality of diamond films grown by Chemical Vapour Deposition (CVD) have made synthetic diamond a very attractive material for detection applications. In this paper, polycrystalline diamond films synthesised by microwave plasma enhanced CVD using a CH₄–CO₂ gas mixture, previously investigated as particle detectors, have been characterised by X-ray diffraction and Raman spectroscopy. The detector response was measured in vacuo under irradiation with 5.5 MeV α-particle from a ²⁴¹Am source. A systematic study of the influence of the film structural properties on the detector performance has been carried out by changing the methane concentration in the growth plasma and the deposition temperature. The existence of a correlation between growth conditions, film texturing and detector performance has been demonstrated. Independently of the substrate temperature, (1 0 0) orientated films exhibit the lowest detection efficiencies. The meas ured collection distances are smaller than the average grain sizes and seem to be limited by trapping centres within the grains. These results are confirmed by Raman analysis. Received: 6 January 1999 / Accepted: 18 January 1999     

CVD-diamond-based thermocouple for high sensitive temperature measurements

The possibility to realize a high sensitive thermocouple by means of boron doped chemical vapour deposition (CVD) diamond was investigated. The thermoelectric power of p-type diamond, grown by plasma enhanced CVD was studied for films of electrical resistivity in the 0.2–40 Ω cm range in order to asses the dependence of thermocouple sensitivity on the doping level. The p-type diamond films were prepared by CH₃OH + B₂O₃ vapour addition to a 1% CH₄–H₂ gas mixture during the growth. The conductive films were then tested tracing the I–V characteristic in order to study the conduction properties of the films. An appropriate experimental setup was built to evaluate the thermoelectric properties of the grown samples for different temperatures imposed between two ends of the samples. Firstly, the output voltage was measured maintaining a reference temperature of 273 K at one end and varying the second temperature between 275.5 and 360.5 K. A constant value of the temperature drop of 5 K was then used for an accurate evaluation of the thermoelectric properties of the diamond films for different value of the average temperature. The measurements provided values of thermoelectric power in the range 0.3–0.6 mV/K while conductivity increases. These values showed different decreasing behaviour with increasing temperature for different resistivity of the sample. In particular, more relevant changes in thermoelectric power were measured for high resistive samples.     

Evidence-based personal applications of medical computing models in risk factors of cardiovascular disease for the middle-aged and elderly

Medical applications on cardiovascular disease (CVD) for hybrid computing models are an emerging research area. The CVD, including stroke, hypertension, and high cholesterol, is one of 10 leading causes of death in Taiwan in middle-aged and elderly; in particular, the CVD has become the top killer in advanced countries. Thus, this serious but interesting issue triggers the study to focus on patients of the CVD. The study explores variables, influencing cardiovascular functions for four risk factors of blood pressure, blood glucose, blood fat, and kidney diseases, in the middle-aged and elderly. By the data collection of regular physical examination system from a regional hospital, the original dataset contains 52 variables collected from October 2011 to February 2014. We model a hybrid knowledge-based classification system to organize expert experiences, integrated linear and nonlinear attribute selection methods, data discretization of smart expert method, rough set theory, the LEM2 algorithm, and rule-filtering technique to classify the CVD for the early warning purpose. After data cleaning, 20 attributes with 2027 records are remained. For effectively identifying the variables of CVD subjects, this study reclassifies the above four risk diseases into three classes: no disease, 1&2 diseases, and 3&4 diseases. To verify performance of the proposed procedure, we experience an empirical experiment to compare the full 20 used attributes, the used attributes of integrated linear and nonlinear attribute selections with rule-filtering technique, and various classifiers. Conclusively, the 13 used attributes obtained from optimal accuracy become the key determinants that affect the four risk factors of the CVD. The empirical results and findings benefit doctors’ and medical institutions’ early medical recommendations and treatments with the advantages of significantly reducing morbidity of CVD.     

基于DSP的金刚石压机智能控制系统设计

本文提出了一种金刚石压机的新型控制模式—基于DSP(TMS320LF2407)的嵌入式控制系统,并介绍了该控制系统的软硬件设计。在算法上,根据工艺要求采用智能PID控制和模糊PID控制策略代替传统的PID控制,对人造金刚石生产中的工艺参数加热功率和加压压力实现有效控制,极大地提高了人造金刚石的质量和品级。