Dual-beam atmospheric turbulence measurement system performance as a high-altitude turbulance scale size sensor

1998 ◽  
Author(s):  
Leonard John Otten III ◽  
Eugene W. Butler ◽  
Michael C. Roggemann ◽  
Anna Consortini
Keyword(s):  
High Altitude ◽  
Atmospheric Turbulence ◽  
Measurement System ◽  
System Performance ◽  
Turbulence Measurement ◽  
Scale Size ◽  
Dual Beam

Atmospheric Turbulence Measurement System

1985 ◽  
Author(s):  
R. W. McMillan ◽  
R. A. Bohlander ◽  
R. H. Platt ◽  
D. M. Guillory ◽  
J. T. Priestley ◽  
...  
Keyword(s):  
Atmospheric Turbulence ◽  
Measurement System ◽  
Turbulence Measurement

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System Performance

2012 ◽  
Vol 19 (2) ◽  
pp. 381-394
Author(s):  
José Pereira ◽  
Octavian Postolache ◽  
Pedro Girão
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Measurement System ◽  
Curve Fitting ◽  
System Performance ◽  
Redox Potentials ◽  
Voltage Sweep ◽  
Gaussian Curve ◽  
Fitting Method ◽  
Curve Fitting Method

Using A Segmented Voltage Sweep Mode and A Gaussian Curve Fitting Method to Improve Heavy Metal Measurement System PerformanceThis paper presents a voltammetric segmented voltage sweep mode that can be used to identify and measure heavy metals' concentrations. The proposed sweep mode covers a set of voltage ranges that are centered around the redox potentials of the metals that are under analysis. The heavy metal measurement system can take advantage of the historical database of measurements to identify the metals with higher concentrations in a given geographical area, and perform a segmented sweep around predefined voltage ranges or, alternatively, the system can perform a fast linear voltage sweep to identify the voltammetric current peaks and then perform a segmented voltage sweep around the set of voltages that are associated with the voltammetric current peaks. The paper also includes the presentation of two auto-calibration modes that can be used to improve system's reliability and proposes the usage of a Gaussian curve fitting of voltammetric data to identify heavy metals and to evaluate their concentrations. Several simulation and experimental results, that validate the theoretical expectations, are also presented in the paper.

A Blade by Blade Tip Clearance Measurement System for Gas Turbine Applications

1994 ◽  
Author(s):  
A. G. Sheard ◽  
B. Killeen
Keyword(s):  
Gas Turbine ◽  
Measurement System ◽  
System Reliability ◽  
System Performance ◽  
Tip Clearance ◽  
Test Facility ◽  
Hostile Environment ◽  
Reliable Measurement ◽  
Blade Tip ◽  
Blade Tip Clearance

It is difficult to make a reliable measurement of running clearance in the hostile environment over the blading of a modern gas turbine. When engine manufacturers require the measurement to be made over every blade during live engine tests, system reliability, ruggedness and ease of operation are of primary importance. This paper describes a tip clearance measurement system that can measure clearance over every blade around a rotor. The measurement system concept is presented, and the system design described in detail. Commissioning of the measurement system on a compressor test facility, and the results obtained are discussed. An analysis of system performance during the commissioning trials concludes the paper.

scholarly journals Error Analysis and Compensation of a Laser Measurement System for Simultaneously Measuring Five-Degree-of-Freedom Error Motions of Linear Stages

Sensors ◽  
2019 ◽  
Vol 19 (18) ◽  
pp. 3833 ◽  
Author(s):  
Yindi Cai ◽  
Qi Sang ◽  
Zhi-Feng Lou ◽  
Kuang-Chao Fan
Keyword(s):  
Measurement System ◽  
Measurement Accuracy ◽  
Measurement Model ◽  
Degree Of Freedom ◽  
Linear Stage ◽  
Laser Measurement ◽  
Beam Spot ◽  
Error Sources ◽  
Laser Measurement System ◽  
Dual Beam

A robust laser measurement system (LMS), consisting of a sensor head and a detecting part, for simultaneously measuring five-degree-of-freedom (five-DOF) error motions of linear stages, is proposed and characterized. For the purpose of long-travel measurement, all possible error sources that would affect the measurement accuracy are considered. This LMS not only integrates the merits of error compensations for the laser beam drift, beam spot variation, detector sensitivity variation, and non-parallelism of dual-beam that have been resolved by the author’s group before, but also eliminates the crosstalk errors among five-DOF error motions in this study. The feasibility and effectiveness of the designed LMS and modified measurement model are experimentally verified using a laboratory-built prototype. The experimental results show that the designed LSM has the capability of simultaneously measuring the five-DOF error motions of a linear stage up to one-meter travel with a linear error accuracy in sub-micrometer and an angular error accuracy in sub-arcsecond after compensation.

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