9762 papers found
In this paper is discussed a novel primary standard which is based on volumetric expansion due to a temporal temperature gradient. The principle, required corrections, traceability and preliminary results are discussed.
The Volume Laboratory (LVO) of the Portuguese Institute for Quality (IPQ), in cooperation with the Department of Mechanical and Industrial Engineering (DEMI) of the Faculty of Science and Technology of The New University of Lisbon (FCT/UNL), developed a gravimetric microflow standard with a range between 10 mL/min and 100 nL/min. The design of the microflow standard was based on three main elements: a flow generator (syringe pump), a collector device and a data acquisition computer program. The microflow standard was tested and validated by means of an ongoing intercomparison, at different...
LDA measurements of airspeed induced by the arm rotation at the measurement position and a definition of actual capabilities of this facility as primary standard according to the WGFF position are described in this paper.
We discuss five significant improvements to the Air Speed Calibration Service conducted by the National Institute of Standards and Technology (NIST): 1. Reduced-uncertainty calibration of the secondary standard [Laser Doppler Anemometer, (LDA)] using a spinning disk, 2. Reduced-uncertainty LDA measurements that account for the position-dependence of the air speed in the test section and for window effects, 3. Improved repeatability, precision, and ease of calibrations by using automated data acquisition and PID air speed control, 4. Optical Character Recognition data acquisition system for...
NMIJ is developing a new standard system for high air speed over 90 m/s.
The paper presents a detailed description of the calibration equipment and procedure of the new Austrian reference laboratory for air speed in the range from 0.04 m/s to 40 m/s.
New air velocity standard facility is established at NIM. The facility is constituted of wind tunnel with outlet diameter of 200mm and LDA that works as standard to calibrate anemometer. In the velocity range of（0.2 ～ 30）m/s, the velocity stability and the deviation of velocity distribution along profile are both less than 0.35%. To realize traceability of LDA the spinning-disc is developed. The wire with diameter of 5 μm is mounted on the edge of spinning disc to simulated tracing particle in air flow. The calibration results and analysis suggest that the expanded uncertainty of fringe...
The paper deals with the methods and means of precision angle calibration with new development of methods for raster scales measuring and vertical angle measurement of geodetic instruments. The calibration of angle information measuring is discussed including rotary encoders, precision circular raster and coded scales. The new development of mechatronic test bench and the results of measurement are described.
Saturation of peripheral oxygen (SpO2) is one of the most important parameters of vital signs. Pulse oximeter which based on near-infrared spectroscopy is commonly used as a non-invasive method to measure SpO2. Currently, medical device manufacturers as well as metrology measurement agencies in China usually use pulse oximeter simulator as the commonly accepted functional calibration equipment for pulse oximeters. So far, there is no experimental protocol or devices can be used to test the accuracy and reliability of a pulse oximeter simulator, therefore, a set of new metrology apparatus...
This paper presents the results of a comparative analysis of the calibration factor measurements of the power sensor model E4413A, manufactured by Agilent, which operates at frequencies from 50 MHZ to 26.5 GHz and power levels from -70 dBm to +20 dBm. The comparison takes into account the values of the calibration certificates provided by INPE’s Integration and Testing Laboratory (INPE/LIT) and two others calibration laboratories: National Physical Laboratory (NPL) of United Kingdom and Brazilian Calibration Laboratory of Agilent. The normalised error is used to evaluate the performed power...