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Spectral Test Instrument for Color Vision Measurement 被引量:1
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作者 Balázs Vince Nagy Gyrgy brahám 《Journal of Bionic Engineering》 SCIE EI CSCD 2005年第2期75-79,共5页
Common displays such as CRT or LCD screens have limited capabilities in displaying most color spectra correctly. The main disadvantage of these devices is that they work with three primaries and the colors displayed a... Common displays such as CRT or LCD screens have limited capabilities in displaying most color spectra correctly. The main disadvantage of these devices is that they work with three primaries and the colors displayed are the mixture of these three colours. Consequently these devices can be confusing in testing human color identification, because the spectral distribution of the colors displayed is the combined spectrum of the three primaries. We have developed a new instrument for spectrally correct color vision measurement. This instrument uses light emitting diodes (LEDs) and is capable of producing all spectra of perceivable colors, thus with appropriate test methods this instrument can be a reliable and useful tool in test~ing human color vision and in verifying color vision correction. 展开更多
关键词 human color vision color vision measurement color spectrum LED instrument
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An overview on observational instruments and measuring methods for dewfall 被引量:1
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作者 Qiang Zhang XiaoCui Hao +2 位作者 XiaoMei Wen Sheng Wang Jian Zeng 《Research in Cold and Arid Regions》 2011年第1期78-85,共8页
This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land sur... This paper systematically summarizes previous measuring methods and observational instruments for the magnitude of dewfall on land surface, analyzes the characteristics of common observational instruments for land surface dewfall, and describes several basic dewfall measurement methods. Moreover, the basic principles of these methods and instruments are interpreted, and their advantages, disadvantages, and applicability are analyzed. Recommendations for the further improvement of these observational instruments and the development of dewfall measuring methods are presented, and new technologies and scientific proposals for exploiting dewfall are elucidated. 展开更多
关键词 dewfall measuring methods observational instrument exploitation and utilization technology
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Automatic Recognition Method for Optical Measuring Instruments Based on Machine Vision 被引量:2
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作者 宋乐 林玉池 郝立果 《Transactions of Tianjin University》 EI CAS 2008年第3期202-207,共6页
Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, ... Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, a 2-layer automatic recognition model for data reading is established after adopting a series of pre-processing algorithms. This model is an optimal combination of the correlation-based template matching method and a concurrent back propagation(BP) neural network. Multiple complementary feature extraction is used in generating the eigenvectors of the concurrent network. In order to improve fault-tolerance capacity, rotation invariant features based on Zernike moments are extracted from digit characters and a 4-dimensional group of the outline features is also obtained. Moreover, the operating time and reading accuracy can be adjusted dy-namically by setting the threshold value. The experimental result indicates that the newly developed algorithm has optimal recognition precision and working speed. The average reading ratio can achieve 97.23%. The recognition method can automatically obtain the results of optical measuring instruments rapidly and stably without modifying their original structure, which meets the application requirements. 展开更多
关键词 机器视觉 自动识别 光学测量工具 神经网络
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PENETRATION RATE MEASUREMENT AND ITS INSTRUMENT DESIGN
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作者 Qiu Zhenyuan 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 1991年第1期14-19,共6页
The practical method for precise penetration rate measurement in a short time and the instrument design have been specially discussed in this paper.Considering the defects of the penetration rate meters available,via ... The practical method for precise penetration rate measurement in a short time and the instrument design have been specially discussed in this paper.Considering the defects of the penetration rate meters available,via the balanced design in consideration of service life,costs,accuracy and reliability,a kind of penetration rate meter has been put forward.The meter consists of a magnetic clutch,a gear box and a raster disk system to pick up the signal.The meter has the following advantages-it might measure a low speed with higher accura-cy,it could disengage automatically without being divorced from the driving device during tripping rods at high speed,it has a circuit of rotary direction discrimination and of repeated counting prevention so as to eU-minate error caused by rod vibration. 展开更多
关键词 penetration rate measurement instrument design magnetic clutch gear box raster disk
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Preliminary Application of Combinatorial Measurement and Regression Analysis Method to High Precision Instrumental Analysis
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作者 Hongyi Zheng 《American Journal of Analytical Chemistry》 2014年第7期415-423,共9页
With determination micro-Fe by 1, 10-phenanthroline spectrophotometry for example, they are systematically introduced the combinatorial measurement and regression analysis method application about metheodic principle,... With determination micro-Fe by 1, 10-phenanthroline spectrophotometry for example, they are systematically introduced the combinatorial measurement and regression analysis method application about metheodic principle, operation step and data processing in the instrumental analysis, including: calibration curve best linear equation is set up, measurand best linear equation is set up, and calculation of best value of a concentration. The results showed that mean of thrice determination , s = 0 μg/mL, RSD = 0. Results of preliminary application are simply introduced in the basic instrumental analysis for atomic absorption spectrophotometry, ion-selective electrodes, coulometry and polarographic analysis and are contrasted to results of normal measurements. 展开更多
关键词 Combinatorial measurement and Regression ANALYSIS Method instrumentAL ANALYSIS High PRECISION APPLICATION
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Integrated On-line Instrumentation System of Magnetic Properties Measurement
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作者 D.G.Park, Y.Y.Song. H.Song and J.H.Hong (Korea Atomic Energy Research Institute, Yusong P.O.Box 105, Taejon, 305-600 Korea) C.G.Kim (Department of Physics, Sun Moon Univ., Asan-si, Chungnam, 336840 Korea) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期248-249,共2页
A portable microcomputer-controlled inspection system has been developed for detection of magnetic properties of soft magnetic materials. It incorporates custom designed software for control of the magnetic field duri... A portable microcomputer-controlled inspection system has been developed for detection of magnetic properties of soft magnetic materials. It incorporates custom designed software for control of the magnetic field during operation such as demagnetization, field sweeping, and for data logging and analysis. Results are recorded using a 12-bit analog to digital converter and are then stored on disk. The magnetic hysteresis loop and Barkhausen noise data can be converted into important magnetic parameters: coecivity, remanence, and hysteresis loss, Barkhausen amplitude, and Barkhausen noise energy. This system incorporated with the magnetostriction, and magnetoacoustic emission, is then related with the nondestructive detection of material degradation. 展开更多
关键词 line Integrated On-line instrumentation System of Magnetic Properties measurement
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Journal of Measurement Science and Instrumentation Contents of Volume 1(2010)
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《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期406-408,共3页
关键词 Journal of measurement Science and instrumentation Contents of Volume 1 CHO 2010
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Analysis of Factors Affecting Logging Quality of Dual Lateral Instruments and Measures
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作者 Qiming Gao 《Journal of Electronic Research and Application》 2019年第1期8-12,共5页
In order to effectively improve the application value of equipment,the quality of dual-sided instrument logging is more important,but it has several influencing factors.This paper analyzes the working principle of dua... In order to effectively improve the application value of equipment,the quality of dual-sided instrument logging is more important,but it has several influencing factors.This paper analyzes the working principle of dual lateral instrument logging,and discusses the factors affecting the logging quality of dual-sided instruments and optimization measures,for reference only. 展开更多
关键词 DUAL LATERAL instrument LOGGING QUALITY influencing FACTORS optimization measures
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2009
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《China Standardization》 2009年第4期69-69,共1页
关键词 JJG National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2009
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2010(2010 No.131)
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《China Standardization》 2011年第1期80-80,共1页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 8 national measuring verification regulations in 2010 and publicize now.
关键词 National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2010 No.131
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2008 2008 NO.35
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《China Standardization》 2008年第6期63-63,共1页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 11 national measuring verification regulations in 2008 and publicize now.
关键词 National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2008 2008 NO.35 JJG NO
全文增补中
National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2008
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《China Standardization》 2008年第4期53-54,共2页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China hasapproved the following 24 national measuring verification regulations in 2008 and publicize now.
关键词 JJG National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2008
全文增补中
National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2008 2008 No.22
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《China Standardization》 2008年第3期54-54,共1页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 10 national measuring verification regulations in 2008 and publicize now.
关键词 JJG National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2008 2008 No.22
全文增补中
基于Visual C#和Measurement Studio融合的虚拟示波器设计开发 被引量:3
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作者 张兵 杨岳 《企业技术开发》 2010年第1期6-7,15,共3页
文章首先介绍了在Visual C#环境下如何引用Measurement Studio控件进行虚拟仪器设计的方法,然后,重点分析了在Visual C#环境下如何调用Measurement Studio相关控件实现虚拟示波器面板设计,文中通过C#编程对数据在虚拟示波器中的动态显... 文章首先介绍了在Visual C#环境下如何引用Measurement Studio控件进行虚拟仪器设计的方法,然后,重点分析了在Visual C#环境下如何调用Measurement Studio相关控件实现虚拟示波器面板设计,文中通过C#编程对数据在虚拟示波器中的动态显示进行了详细的分析。 展开更多
关键词 虚拟仪器 示波器 Visual C# measurement STUDIO
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INTELLIGENT VIRTUAL CONTROL:MEASURING INSTRUMENT FROM WHOLE TO PART 被引量:19
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作者 Qin Shuren Tang BaopingCollege of Mechanical Engineering, Chongqing University, Chongqing 400044, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第2期131-135,共5页
A new concept called intelligent virtual control (IVC), which can be drivenby measuring functions, is put forward. This small 'intelligent measurement instrument unit (IMIU)',carrying with functions of instrum... A new concept called intelligent virtual control (IVC), which can be drivenby measuring functions, is put forward. This small 'intelligent measurement instrument unit (IMIU)',carrying with functions of instrument, consists of different types of intelligent virtualinstrument (IVI) through individual components together as building blocks and can be displayeddirectly on the computer screen. This is a new concept of measuring instrument, and also animportant breakthrough after virtual instrument (VI). Virtual control makes instrument resourcesobtain further exploitation. It brings about a fundamental change to the design and manufacturingmode. The instrument therefore, can not only be produced directly inside a PC, but the product isinvolved in the 'green product' system. So far, all the present digital instruments will grow to bereplaced by intelligent control with green characteristics. 展开更多
关键词 Intelligent virtual control measurement instrument Whole Part
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基于.NET及Measurement Studio的USB型测试系统研制 被引量:5
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作者 袁威 夏春明 +1 位作者 刘长利 郑建荣 《测控技术》 CSCD 2007年第5期49-51,57,共4页
介绍了一种基于.NET框架环境及Measurement Studio.NET的USB接口型通用多路高速并行采集测试分析系统的开发,以及针对振动设备监测的常用算法开发应用。该系统充分体现虚拟仪器的概念,以计算机为主体,以测试分析软件为核心,配备传感... 介绍了一种基于.NET框架环境及Measurement Studio.NET的USB接口型通用多路高速并行采集测试分析系统的开发,以及针对振动设备监测的常用算法开发应用。该系统充分体现虚拟仪器的概念,以计算机为主体,以测试分析软件为核心,配备传感器、数据采集模块等外围设备,以较低的成本,完成了各种传统信号测试仪器的功能。测试系统软件建立在.NET开发平台上,以C#语言与NI公司的Measurement Studio混合编程实现测试算法及用户界面。另外,系统界面友好、操作简便、可移植性强,已在振动设备测试方面进行了初步应用。 展开更多
关键词 虚拟仪器 数据采集 数字信号处理 VISUAL STUDIO.NET measurement STUDIO.NET
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Nuclear Magnetic Resonance Measurements of Original Water Saturation and Mobile Water Saturation in Low Permeability Sandstone Gas 被引量:8
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作者 高树生 叶礼友 +2 位作者 熊伟 郭和坤 胡志明 《Chinese Physics Letters》 SCIE CAS CSCD 2010年第12期217-218,共2页
We use nuclear magnetic resonance (NMR) and centrifugation to measure the original water saturation and mobile water saturation of cores from the Xujiahe low permeability sandstone gas reservoir, and compare the NMR... We use nuclear magnetic resonance (NMR) and centrifugation to measure the original water saturation and mobile water saturation of cores from the Xujiahe low permeability sandstone gas reservoir, and compare the NMR results with the corresponding field data. It is shown that the NMR water saturation after 300psi centrifugation effectively represents the original water saturation measured by weighing fresh cores. There is a good correlation between mobile water saturation and the water production performance of the corresponding gas wells. The critical mobile water saturation whether reservoir produces water of the Xujiahe low permeability sandstone gas is 6%. The higher the mobile water saturation, the greater the water production rate of gas well. This indicates that well's water production performance can be forecasted by mobile water saturation of cores. 展开更多
关键词 instrumentation and measurement Plasma physics
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Self-heating Probe Instrument and Method for Measuring High Temperature Melting Volume Change Rate of Material 被引量:2
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作者 WANG Junwei WANG Zhiping +1 位作者 LU Yang CHENG Bo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期371-376,共6页
The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics ... The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics of existing measuring installations are complex structure, troublesome operation and low precision. In order to measure the melting volume change rate of material accurately and conveniently, a self-designed measuring instrument, self-heating probe instrument, and measuring method are described. Temperature in heating cavity is controlled by PID temperature controller; melting volume change rate υ and molten density are calculated based on the melt volume which is measured by the instrument. Positive and negative υ represent expansion and shrinkage of the sample volume after melting, respectively. Taking eutectic LiF+CaF2 for example, its melting volume change rate and melting density at 1 123 K are -20.6% and 2 651 kg/m–3 measured by this instrument, which is only 0.71% smaller than literature value. Density and melting volume change rate of industry pure aluminum at 973 K and analysis pure NaCl at 1 123 K are detected by the instrument too. The measure results are agreed with report values. Measuring error sources are analyzed and several improving measures are proposed. In theory, the measuring errors of the change rate and molten density which are measured by the self-designed instrument is nearly 1/20-1/50 of that measured by the refitted mandril thermal expansion instrument. The self-designed instrument and method have the advantages of simple structure, being easy to operate, extensive applicability for material, relatively high accuracy, and most importantly, temperature and sample vapor pressure have little effect on the measurement accuracy. The presented instrument and method solve the problems of complicated structure and procedures, and large measuring errors for the samples with high vapor pressure by existing installations. 展开更多
关键词 high temperature volume expansion rate molten density measuring instrument measuring method
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基于Measurement Studio的太阳能路灯监控系统 被引量:1
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作者 郭珍珍 郭前岗 周西峰 《微型机与应用》 2013年第1期71-73,79,共4页
研究了基于虚拟仪器技术Measurement Studio的太阳能LED路灯监控系统。采用GPRS与CAN总线的两级式网络,实时采集参数,并将数据传输给上位机监控系统,用于绘制参数曲线并存储、分析数据。给出了总体网络结构、单个节点电路、通信接口电... 研究了基于虚拟仪器技术Measurement Studio的太阳能LED路灯监控系统。采用GPRS与CAN总线的两级式网络,实时采集参数,并将数据传输给上位机监控系统,用于绘制参数曲线并存储、分析数据。给出了总体网络结构、单个节点电路、通信接口电路、调理电路以及软件系统设计流程图,同时还给出了基于多线程技术的软件性能优化方案。 展开更多
关键词 虚拟仪器技术 measurement STUDIO 太阳能路灯监控 多线程 GPRS
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Measurement of Electron-Drift Velocity in Ar+CH4 Mixtures Using Double-Grid Method 被引量:1
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作者 张家国 张国辉 陈金象 《Chinese Physics Letters》 SCIE CAS CSCD 2009年第11期41-44,共4页
Based on analyzing the induced signals from the double-grids of an ionization chamber, the electron-drift time between the two grids is determined and the electron-drift velocity is derived. A waveform digitizer is em... Based on analyzing the induced signals from the double-grids of an ionization chamber, the electron-drift time between the two grids is determined and the electron-drift velocity is derived. A waveform digitizer is employed to record pulses from the two grids of the ionization chamber. The electron-drift velocity is measured as a function of the reduced electric field E/p for eight different ratios of Ar+CH4 mixtures. By analyzing the experimental data of this study, self-consistency of experimental data is achieved, and formulae for calculating electron-drift velocity in any ratio of Ar+CH4 mixtures are obtained. 展开更多
关键词 ACCELERATORS beams and electromagnetism Nuclear physics instrumentation and measurement Plasma physics Particle physics and field theory
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