液体流量仪表在线校准方法及趋势

针对液体流量仪表无法离线送检的情况，介绍了液体流量仪表在线校准的几种方法。重点介绍了超声流量计用于在线校准时出现的问题和解决办法。最后指出电参数法和基于虚拟仪器的超声相关法是未来液体流量仪表在线校准的发展方向。     

虚拟仪器的校准

本文介绍了虚拟仪器的概念,说明了虚拟仪器的一般结构,阐述了现阶段虚拟仪器校准中应该注意的几个问题,进一步探讨了虚拟仪器的校准方法和内容.     

在线综合参数校验技术在油田计量中的应用

<正>智能化油田的有效运行是以及时、准确的计量数据为基础,但受拆卸、更换、运输等因素影响,许多计量仪表无法开展实验室检定。为此,采油厂开展了在线综合参数校验技术的研究,将虚拟仪器技术引入检定过程中,开发在线综合参数校验仪,实现对计量器具的在线校准和修复功能,进一步提高计量技术机构的工作效率和服务保障能力。一、在线综合参数校验技术基于"软件=仪器"的理论,虚拟仪器技术是实现     

基于虚拟仪器的专用测试设备校准探讨

介绍了虚拟仪器组成原理,对基于虚拟仪器的专用测试设备的误差及校准进行了分析,探讨了通讯总线接口、数字IO通道、模拟量采集通道的校准。     

采用虚拟仪器技术实现测振仪及振动传感器自动化检定

随着计算机技术的迅速发展．虚拟仪器已经成为未来仪器发展的重要方向。我们针对工作测振仪、振动传感器的检定、校准工作．采用美国NI公司的LabVIEN虚拟仪器开发平台设计开发了专用设备及测试程序。     

基于虚拟仪器技术的示波器校准仪设计

文章介绍了一个基于虚拟仪器技术的示波器校准仪的设计与研发。示波器校准仪成为计算机和传统仪器的有机组合，使用虚拟仪器技术，计算机控制各信号产生单元输出各种校准用信号，并用软件实现了示波器的自动化检定／校准。实际应用表明该仪器满足示波器的手动或自动检定／校准工作的要求。     

虚拟仪器的准确度及其测试

从计量学的角度上看，只要技术上可行．大多数计量系统都可以用虚拟仪器代替。如何针对虚拟仪器的测量特点对其计量性能进行校准，已经成为校准领域的一个重要课题。     

虚拟压力校准仪校准技术研究

概述虚拟仪器所带来的传感器观念新的变革,同时介绍用虚拟仪器语言LabWindows/CVI研制的压力传感器计量和实时校准软件,用虚拟仪器语言和MATLAB、ActiveX技术连接和密切结合,为虚拟仪器校准仪提供了更为广阔的应用前景。     

复合物理量的在线校准

在线进行物理量的校准,就是最大程度地还原各项仪器设备的原始状态,从中抽取需要校准的物理量,包括力值、扭矩、速率、位移等,使用相匹配的标准装置进行相关物理量的量值传递。首先简单介绍了在线校准与实验室校准的区别,并通过具体案例介绍了在线校准的实施过程;然后阐述了在线校准过程中所面临的诸多问题与实际困难;最后,对在线校准的未来发展进行了展望。     

质量法在线校准液体流量计的方法探讨

文章介绍了质量法在线校准液体流量计的一般方法,详细阐述了在线校准前和校准过程中的特殊要求和注意事项,结合实际给出了在线校准的相关说明;并以质量法在线校准科氏力质量流量计为例,参照JJG 1038—2008《科里奥利质量流量计》,给出了测量数据和不确定度评定。     

CNC数控机床在线测量系统的校准装置研究

目前,国内尚无针对CNC数控机床在线测量系统的相关的标准和校准规范.为统一技术要求,本文研究了CNC数控机床在线测量系统的工况条件及其计量特性参数,提出了有别传统三坐标测量机校准方法的校准方案,研制了符合基于公差带位置判别废品原理的标准器组,以在线测量系统的测工件的方式,反向校准CNC在线测量系统的尺寸精度,解决其量值...     

CNC机床在线测量系统校准方法研究

目前CNC机床在线测量系统的校准方法在国内有用激光干涉仪、标准量块等一些用于企业的针对性方法,缺少适用于计量校准机构的校准方法,本文根据该系统的工作原理,对CNC机床在线测量系统的校准方法进行研究,提出几项计量特性参数,并结合实际情况设计了校准方案,研制了校准用计量标准器,分析了数据的处理方法。经研究表明,本文的校准方案切实可行,为CNC机床在线测量系统提供了技术依据。     

视频引伸计标定装置设计及标定方法研究

视频引伸计被用于测量材料的变形,需要进行在线标定和校准,然而目前尚无相应的标准和校准规范的指导,针对此,设计了一种光栅式引伸计在线标定装置,主要由控制器、步进电机、机械传动机构、光栅位移传感器、显示器以及上标定板、下标定板组成。第三方校准结果显示,该装置标距标定板最大相对示值误差为0.07%(Urel=0.04%,k=2);光栅位移部分技术指标:小于等于1/3mm时,绝对误差小于0.3μm(U=0.1μm,k=2),大于1/3mm时,相对误差小于0.1%(Urel=0.04%,k=2),技术指标明显优于使用要求。用该装置对视频引伸计进行了重复性和稳定性验证实验,对标定结果评定了不确定度。结果表明:该装置技术指标完全满足视频引伸计的在线标定。     

HERA-B framework for online calibration and alignment

This paper describes the architecture and implementation of the HERA-B framework for online calibration and alignment. At HERA-B the performance of all trigger levels, including the online reconstruction, strongly depends on using the appropriate calibration and alignment constants, which might change during data taking. A system to monitor, recompute and distribute those constants to online processes has been integrated in the data acquisition and trigger systems.     

X-ray absorption near edge structure and extended X-ray absorption fine structure analysis of standards and biological samples containing mixed oxidation states of chromium(III) and chromium(VI)

For the first time a method has been developed for the extended X-ray absorption fine structure (EXAFS) data analyses of biological samples containing multiple oxidation states of chromium. In this study, the first shell coordination and interatomic distances based on the data analysis of known standards of potassium chromate (Cr(VI)) and chromium nitrate hexahydrate (Cr(III)) were investigated. The standards examined were mixtures of the following molar ratios of Cr(VI):Cr(III), 0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25, and 1:0. It was determined from the calibration data that the fitting error associated with linear combination X-ray absorption near edge structure (LC-XANES) fittings was approximately +/-10% of the total fitting. The peak height of the Cr(VI) pre-edge feature after normalization of the X-ray absorption (XAS) spectra was used to prepare a calibration curve. The EXAFS fittings of the standards were also investigated and fittings to lechuguilla biomass samples laden with different ratios of Cr(III) and Cr(VI) were performed as well. An excellent agreement between the XANES data and the data presented in the EXAFS spectra was observed. The EXFAS data also presented mean coordination numbers directly related to the ratios of the different chromium oxidation states in the sample. The chromium oxygen interactions had two different bond lengths at approximately 1.68 and 1.98 A for the Cr(VI) and Cr(III) in the sample, respectively.     

汽车安全检测设备标定系统研究

针对目前国内汽车安全检测设备由人工标定且数据非自动处理而导致工作量大和人为误差较大的问题,利用数据采集技术、UML建模技术和数据库原理,设计出汽车安全检测设备标定系统,实现对检测设备的自动化标定,提高了设备标定的精度和准确度。系统主要由信号采集模块、标定软件、通用标定器具和检测设备专用标定器具等部分组成,可以实现离线标定和在线标定。系统具有灵活配置、快速标定及通用性强的优点,可以满足不同规模检测站的需求,较好地解决了汽车检测设备标定工作中存在的不足。     

Calibration modeling for mobile vision based laser imaging and approximation networks

A mobile calibration technique for three-dimensional vision is presented. In this technique, the parameters of mobile vision are computed automatically by approximation networks and image processing of a laser line. Also, the three-dimensional vision is performed by the networks. The proposed vision system provides online geometric modifications from the initial configuration. Here, an online re-calibration is performed via network data to determine the setup modifications. Thus, vision limitations caused by the geometric modifications are overcome. The network is built based on the behavior of the laser line and the camera position. In this manner, the network provides the data for the automatic re-calibration. This system avoids calibrated references and external procedures for re-calibration. Therefore, the calibration model improves the accuracy and performance of the mobile vision. It is because the external data are not passed to the procedure of the three-dimensional vision. This kind of modeling represents a contribution for calibration of mobile vision. To elucidate this contribution an evaluation is carried out based on the calibration via perspective projection model. The time processing is also described.     

卫星太阳敏感器模拟器校准技术研究

针对卫星姿轨控半实物仿真系统的技术要求,提出了一种用于太阳敏感器模拟器的校准装置。校准装置以FPGA和AVR单片机为控制核心,微型单板电脑模拟动力学计算机,通过网口进行指令的上传下达。内置信号调理电路、高精度采集模块,数据解算模块等。该校准装置集成度高,替代了原有由数字表、动力学计算机等组成的复杂校准系统,有效地降低了成本,提升效率约40%,实现了太阳敏感器模拟器的快速全过程在线校准。     

Calibration enhancement and on line accuracy assessment for singlesix-port reflectometers employing a nonlinear Kalman filter

The calibration and measurement performance of a single six-port reflectometer is directly affected by the presence of random errors. A technique using a nonlinear Kalman filter that enhances calibration by a factor of two to ten is presented. The technique also provides statistical information, allowing simple online accuracy assessment. The technique is readily extended for use within dual six-port reflectometer systems     

激光在线校准测量

许多工业制造装备的工作过程中,需实施不同规格回转体直径及安装偏心量的快速校准测量,以保证可靠.性.研究组合式激光在线校准系统的工作机理,建立相应的测量信号表达式,给出系统设计的一般原则,理论分析结果表明,校准系统能够实现微米级的校准精度,结合系统在高精度PCB锣钻机的应用实践,理论与实际的吻合性较好.文中提出的分析方法可应用于车床,铣床,加工中心等需实施回转体直径和偏心量的快速在线校准设计.