scholarly journals Calibration of Mangerud'S Boundaries

Radiocarbon ◽  
2010 ◽  
Vol 52 (4) ◽  
pp. 1639-1644 ◽  
Author(s):  
Adam Walanus ◽  
Dorota Nalepka
Keyword(s):  
Measurement Error ◽  
Calibration Procedure ◽  
Radiocarbon Age ◽  
Measurement Results ◽  
Standard Calibration ◽  
Typical Measurement ◽  
Natural Situation

The “calibration” of arbitrarily defined (in some sense, “conventional”) ages, given in conventional radiocarbon years BP, is now becoming necessary because the term “radiocarbon age” is used less often in archaeological and Quaternary practice. The standard calibration procedure is inappropriate here because Mangerud's boundaries are not measurement results. Thus, another approach to the problem is proposed in order to model the natural situation of many, uniformly distributed, dated samples, which should be similarly divided by the original and “calibrated” boundary. However, the result depends on the value of the typical measurement error and is not unequivocal.

scholarly journals Threat object classification with a close range polarimetric imaging system by means of H-α decomposition

2014 ◽  
Vol 6 (3-4) ◽  
pp. 415-421 ◽  
Author(s):  
Julian Adametz ◽  
Lorenz-Peter Schmidt
Keyword(s):  
Imaging System ◽  
Object Classification ◽  
Calibration Procedure ◽  
Radar Data ◽  
Weighted Averaging ◽  
Polarimetric Synthetic Aperture Radar ◽  
Security Applications ◽  
Measurement Results ◽  
Close Range ◽  
Thick Layers

In this paper, an approach to differentiate between various dielectric threat objects in security applications is investigated. The scattering information in form of the Sinclair matrix of relevant scenarios is gained from a fully polarimetric, synthetic aperture radar. Both monostatic and multistatic array configurations are examined. A possible polarimetric calibration procedure is presented. The radar data are processed with the H-α decomposition algorithm. The H-α scattering characteristics of threat objects are analyzed in terms of a weighted averaging. It is shown that an object classification is possible even for threat objects conceiled under thick layers of clothing. Measurement results are presented to illustrate the topic.

scholarly journals In Situ Calibration of Hot-Film Probes Using a Collocated Sonic Anemometer: Implementation of a Neural Network

2010 ◽  
Vol 27 (1) ◽  
pp. 23-41 ◽  
Author(s):  
E. Kit ◽  
A. Cherkassky ◽  
T. Sant ◽  
H. J. S. Fernando
Keyword(s):  
Neural Network ◽  
Sonic Anemometer ◽  
Input Voltage ◽  
Calibration Method ◽  
Calibration Procedure ◽  
Approximation Technique ◽  
Sonic Anemometers ◽  
Standard Calibration ◽  
Hot Film

Abstract Although the integral quantities of atmospheric turbulence are conveniently measured using sonic anemometers, obtaining relevant finescale variables such as the kinetic energy dissipation using conventional hot-film/wire techniques remains a challenge because of two main difficulties. The first difficulty is the mean wind variability, which causes violation of the requirement that mean winds have a specific alignment with the hot-film/wire probe. To circumvent this problem, a combination of collocated sonic and hot-film anemometers, with the former measuring mean winds and aligning the latter in the appropriate wind direction via an automated platform, is successfully designed and implemented. The second difficulty is the necessity of frequent and onerous calibrations akin to hot-film anemometry that lead to logistical difficulties during outdoor (field) measurements. This is addressed by employing sonic measurements to calibrate the hot films in the same combination, with the output (velocity) to input (voltage) transfer function for the hot film derived using a neural network (NN) model. The NN is trained using low-pass-filtered hot-film and sonic data taken in situ. This new hot-film calibration procedure is compared with the standard calibration method based on an external calibrator. It is inferred that the sonic-based NN method offers great potential as an alternative to laborious standard calibration techniques, particularly in the laboratory and in stable atmospheric boundary layer settings. The NN approximation technique is found to be superior to the conventionally used polynomial fitting methods when used in conjunction with unevenly spaced calibration velocity data generated by sonic anemometers.

Effect of Purging Rate on the Calibration of Dew Point Sensor and the Estimation of Measurement Uncertainty

2014 ◽  
Vol 627 ◽  
pp. 161-167 ◽  
Author(s):  
Yun Kyung Bae ◽  
Dong Hoon Hyun
Keyword(s):  
Measurement Uncertainty ◽  
Calibration Procedure ◽  
Standard Uncertainty ◽  
International Standards ◽  
Dew Point ◽  
Measurement Condition ◽  
Testing Laboratory ◽  
Standard Calibration ◽  
Set Up ◽  
Uncertainty Source

The purpose of this paper is to study the effect of purging rate on calibration or test of the dew point sensors and estimation of measurement uncertainty. The measurement is carried out to analyze the variation on measured dew point temperatures for the sample dew point sensors (DPS) due to various durations of purge by using calibrated standard chilled mirror hygrometer. To set up measurement condition, the whole measurement system were kept in the state of purging for 3 hours, 15 hours, 65 hours, 140 hours, 200 hours. The dew point temperatures were measured in the range from-50 °C to 10 °C. In order to investigate the effect of purging rate as an uncertainty source on the measurement uncertainty, the contributions to the standard uncertainty for purging rate were also estimated due to reference dew point temperatures. The measurement was conducted according to standard calibration procedure of Korea Testing Laboratory which assures suitability and traceable results. It is also based on international standards.

An Investigation of Various Factors Affecting Measurement Accuracy of the Tekscan Seat Pressure System

1996 ◽  
Vol 40 (20) ◽  
pp. 1036-1040 ◽  
Author(s):  
Hongzheng Lu ◽  
Gang Lin
Keyword(s):  
Measurement Error ◽  
Contact Area ◽  
Contact Time ◽  
Measurement Accuracy ◽  
Time Interval ◽  
Pressure System ◽  
Factors Affecting ◽  
Measurement Results ◽  
Accuracy Of Measurement ◽  
Pressure Measurement System

This study investigated the following factors affecting the measurement accuracy of the seat pressure measurement system made by TekScan, Inc.: (a) contact time; (b) contact area; (c) the amount of force applied on the pressure mat at the time of calibration and at measurement; and (d) the consistency of contact time before calibration and measurement, and the time interval between calibration and measurement. Results show that the above factors significantly affect the accuracy of measurement. The measurement error can be limited by controlling the contact time for both calibration and measurement to 2 minutes, and controlling the contact area and applied force equally at calibration and measurement.

Optimal Weighted Least Square Data Fusion Method for Redundant IMU Based on Calculation of Measurement Error

2012 ◽  
Vol 241-244 ◽  
pp. 149-155
Author(s):  
Chuan Xing ◽  
Hai Zhang
Keyword(s):  
Measurement Error ◽  
Data Fusion ◽  
Measurement Errors ◽  
Least Square Method ◽  
Least Square ◽  
Weighted Least Square ◽  
Weighted Matrix ◽  
Measurement Results ◽  
The Difference ◽  
Projection Error

A dodecahedron non-orthogonal redundant IMU configuration was selected as model. To improve fusion accuracy, we proposed an effective calculation method for measurement errors based on the correlation between measurement errors and fusion errors. The method considered the difference between traditional data fusion vector’s projection and measurement results, and then made a conversion from projection error to measurement error. Combined with optimal weighted least square method, measurement error was used to generate an optimal weighted matrix, and this made data fusion errors minimum. Simulations also proved that the fusion result of this method is more accurate than the result of traditional method.

Challenge for the Traceable Dimensional Measurement Using CMM in Factory Floor

2017 ◽  
Vol 870 ◽  
pp. 243-248
Author(s):  
Osamu Sato ◽  
Kazuya Matsuzaki ◽  
Hiroyuki Fujimoto ◽  
Sonko Osawa ◽  
Makoto Abe ◽  
...  
Keyword(s):  
Measuring Equipment ◽  
Three Dimensional ◽  
Calibration Procedure ◽  
Measuring Device ◽  
Dimensional Measurement ◽  
Temperature Measuring ◽  
Measurement Results ◽  
Temperature Measuring Instrument ◽  
Three Dimensional Coordinate ◽  
Factory Floor

Dimensional measurement is a key process in the quality assurance of manufacturing. Not only classical one-dimensional measurement devices, several kind of three-dimensional coordinate measuring systems (CMSs) including coordinate measuring machines (CMMs) are used for dimensional measurement tasks in measurement rooms or in factory floors. For the purpose of the quality guarantee, the measurement for the validation on the products should be performed with the traceable manner. In the case of the dimensional measurement, the measurement results of the products should be stated as the corresponding values in the reference temperature, 20 °C. Therefore, at least the traceability of the length indication instruments and temperature-measuring equipment installed into the measuring device to be used should be ensured. Usually, the traceability of the instrument or equipment is ensured through the calibration on it. Now, typical CMMs in factory floor have non-calibrated temperature-measuring equipment because the equipment is hard to be detached off for the calibration, and therefore, the temperature-measuring equipment is usually left uncalibrated. Recently, a new procedure by which both the length indication instruments and temperature-measuring equipment installed into a CMM are able to be calibrated simultaneously is established. In this research, the traceable dimensional measurement using a CMM equipped with uncalibrated temperature-measuring instrument is developed by as an application of the established calibration procedure. Through the experiment, the traceable dimensional measurement using the CMM placed on the factory floor is demonstrated.

scholarly journals Effects of probes with different structures on the flow field and measurement results of imported compressors

2021 ◽  
Vol 39 (4) ◽  
pp. 858-864
Author(s):  
Guanghua Zheng ◽  
Fei Shui ◽  
Jinxin Hu ◽  
Xin Liu ◽  
Huazhong Xiao
Keyword(s):  
Measurement Error ◽  
Flow Field ◽  
Flow Rate ◽  
Total Pressure ◽  
Measurement Accuracy ◽  
Probe Measurement ◽  
Pressure Probe ◽  
Temperature Probe ◽  
Measurement Results ◽  
Total Temperature

In this paper, the measurement accuracy of two different types of total pressure probe and total temperature probe in turboshaft engine compressor inlet channel and the influence of these two probes on the flow field through numerical simulation was studied. At the same time, the influence of the probe structure and installation position on probe measurement results under three typical working conditions of cruise, maximum continuous and takeoff was analyzed. The simulation results showed that the higher the engine inlet flow rate, the greater the measurement error of the probe. Comparing with the total temperature probe, the total pressure probe measurement accuracy is more influenced by the flow rate. The velocity uniformity is less affected by the engine operating conditions and is mainly related to the structure of the inserted probes. The closer the total pressure probe to the support plate, the greater the measurement error. The probe installation position has a small effect on the total pressure loss coefficient at the outlet.

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