Abstract:The navigation user terminal is an important part of the satellite navigation system. It has diverse species and its functionality varies. It’s of great significance to test its functionality and performance. Thus navigation terminal testing technique has become one of the core technologies of satellite navigation applications. This paper makes a systematic presentation on four kinds of testing environment based on a project. It leads to the necessity and urgency of carrying out research on a public test platform.

Abstract:This paper briefly introduces the necessity of test cell thrust calibration technology of aero vector engine and the existing calibration methods of turbofan engine axial test cell thrust measuring system. Referring to structural characteristics of vector thrust test cell, its present situation is analyzed and the field calibration procedures of vector thrust test cell is given. Finally, the future research of test cell thrust calibration technology of aero vector engine in China is discussed.

Abstract:This paper presents a modeling approach which can effectively improve meter accuracy. This model, which combines the improved gray system and particle swarm optimization, uses a small amount of the instrument known error data as training data to get the full-scale error fitting model. Then the model can be used to amend all values in the range. The system has the advantages of economy, practicality and high accuracy proved by experiments.

Abstract:A pressure working condition correction method for temperature measuring deviation calibration results of temperature sensors is proposed in this paper. As an example, temperature measuring deviation of a certain bare-typed temperature sensor is corrected. According to Reynolds criterion, calculated correction results of temperature measuring deviation is validated by the method which replaces change of pressure by that of Mach number. The results show that calculated correction results are near experiment data, and the proposed correction method can not only provide foundation for this type of temperature sensors, but also give reference for other types of temperature sensors.

Abstract:A laser based straightness measurement system for tube type works is designed in this paper. The technologies about centering, diameter acquiring and straightness computing are also developed. The self-centering sub-system uses a double cone coaxial centering method to achieve high-precision centering. Center coordinates are obtained by PSD and collimated laser. A rotation scanning sub-system is used to obtain radius and angle measurements which are used to rectify the centering error by applying least squares circle fitting algorithm. The straightness of the tube type work to be measured is finally calculated by using the above data obtained. Experimental results show that the system centering accuracy is up to 20μm, radial measurement accuracy up to 5μm, measurement repeatability up to 7μm, and straightness measurement accuracy less than 40μm.

Abstract:A passively mode-locked fiber ring laser with a small segment of Er3+-doped fiber as gain medium, pumped by a stable 980 nm laser diode and mode-locked by the nonlinear polarization rotation (NPR) technique, was successfully achieved. When the laser was pumped at 650 mW, stable mode-locked pulses centered at 1560 nm with 163 fs pulse width. The repetition rate is 31.25 MHz. The laser presented here has advantages of being easy to operate and adjust, long-running and better stability. The fiber structure is of miniaturization, integration and portability.

Abstract:This paper proposes a kind of seawater pH standard material more suitable for the measurement of pH in seawater, and studies the methods of preparation and setting method of small batch process for the preparation of the standard material. The pH value in seawater reference material determined by spectrophotometry is carried out to evaluate the homogeneity and stability of the seawater pH standard material prepared by F test and t test method. The experimental results show that both homogeneity and stability, in six month at room temperature, of this seawater pH standard material in artificial seawater are good.

Abstract:Traceable measurement of 2-D Line Scale templates needs high resolution aim at the crosswire. In the 2-D dynamic photoelectric microscope, the image of crosswire is illuminated on two sets of slits which are mutually perpendicular. There are two slits in each set, which have the same width with the image of crosswire. And the distance between the two slits in width direction is also the same size. When the template moves in one of the directions, the image of crosswire will appear in the two slits successively. The luminous flux of the slits will change one after another, which means there is a phase difference between the photoelectric receivers of corresponding slits. And the signal processing system judges the aiming moment using those two signal. In this way, 2-D Dynamic Photoelectric Microscope can realize high resolution 2-D collimation.

Abstract:Wireless pressure acquisition instruments are widely used for calibrating pressure sterilization and other pressure vessel. The application temperature of wireless pressure acquisition instruments is different from other pressure instruments. A kind of calibration device was designed for wireless pressure acquisition instruments. The device adopts three-section temperature control and automatic pressure regulation, and can be used for automatic calibration of wireless pressure acquisition instruments. The experimental results show that the uncertainty of the device can meet the requirement of the wireless pressure acquisition calibration.

Abstract:A new standard Rockwell Hardness device with intelligent force-loading and laser measuring technology was presented in this paper. It adopted servo-motor and dead weights to carry out intelligent force loading, and used the technology of laser heterodyne interferometer to realize no-contact and high-precision measurement of indentation depth. The test results prove that this standard device is stable and reliable. The technical specifications meet the requirements of the new definition of the international Rockwell Hardness draft criterion. It has high practical value.

Abstract:A monitoring system which can monitor the weighting data in the actual working conditions at real time was designed for solving the cheat with software in truck scale. The system uses an A/D weighting module for measuring weight, the hardware is based on human machine interface, and the software is designed with SCADA. The real-time data of the system is stored with SD card and transferred with 3G module. The test results show that the system is not only simple in architecture and stable in working, but also meets the design requirements and has a good application prospect.

Abstract:A testing system was improved as for the poor stability and accuracy in the water flow test of one aeroengine high-pressure turbine guide-vane. A closed-loop control system and one equivalent circuit were added to the testing device, the seal changed from partial seal around the air intakes to the overall seal covering the up and down edge of the blade, the fixture had four intakes instead of the original two, and the assembly process of air duct was optimized. The testing system after being improved was tested, and it proves that the testing pressure stability and good sealing are achieved, and the repeated measuring error and the dispersion degree of measuring both meet the design requirements as well as testing efficiency is effectively improved.

Abstract:This article presented the advantages of gas chromatography - tandem triple quadrupole mass spectrometer (GC-MSMS) over gas chromatography-mass spectrometer, formulated a calibration method of GC-MSMS equipped with the source of electron impact (EI), by the reference to JJF1164-2006 “Calibration Specification for Bench Top Gas Chromatography-Mass Spectrometers”, and described in details the calibration process。The result data show that the method can be applied to the calibration of this instrument。

Abstract:The development of Beidou Satellite navigation system triggered a wave of Beidou receivers development at home and abroad. Users pay more attention to the performance and reliability of Beidou receivers, and the calibration of the Beidou receivers has become an urgent issue. This paper introduces several calibration methods of positioning accuracy for Beidou receivers, and compares these methods through calibration experiments.

Abstract:Optical electric field probes have been gradually applied to measure the radiation capability of phased array radar antennas. Therefore, more attention is paid on how to accurately measure the amplitude and phase of this method. This paper introduces the idea of electric field probe calibration, and proposes a method of using electric field of the rectangular metal waveguide to generate a standard signal containing amplitude and phase to calibrate the optical electric field probe’s measurement capability. The design and production of the calibration device is elaborated in this paper. Experiment results show that this method is able to calibrate the optical electric field probe’s measurement capability, and the precision meets the requirements.

Abstract:Accurate positioning of measuring ends of thermocouples has an important influence on the calibration and use of thermocouples, especially for armored noble metal thermocouples. It is impossible to accurately identify the position of thermocouple measuring ends inside protection tubes by visual inspection, and therefore the top of protection tubes is chosen as the position for measuring ends in the calibration and use processes of thermocouples. However, through field test, the measuring ends of armored noble metal thermocouples are not located at the top of protection tubes. This paper provides a method for accurate positioning of armored noble metal thermocouple measuring ends.

Abstract:The principles of analog resistance are elaborated and suggestions are put forward that the effects of both excitation current magnitude and excitation current direction should be considered for calibrating the analogresistance. Different grades of analog resistance should be calibrated by different devices to improve work efficiency. The GUM method and MCM method are used in evaluating the measurement uncertainty of analog resistance calibration. The evaluation results are basically identical, proving that the evaluation of measurement uncertainty is reasonable. The verification of the measurement uncertainty demonstrates the feasibility and practicability of the calibration method.