A Statistical Analysis of X-ray Stress Measurement by the Gaussian Curve-Fitting Method

1981 ◽  
Vol 9 (5) ◽  
pp. 285 ◽  
Author(s):  
R Horstman ◽  
KA Peters ◽  
BM Schindler ◽  
RL Meltzer ◽  
M Bruce Vieth ◽  
...  
1984 ◽  
Vol 12 (1) ◽  
pp. 13 ◽  
Author(s):  
R Horstman ◽  
KA Peters ◽  
RL Meltzer ◽  
MB Vieth ◽  
M Kurita ◽  
...  

2012 ◽  
Vol 19 (2) ◽  
pp. 381-394
Author(s):  
José Pereira ◽  
Octavian Postolache ◽  
Pedro Girão

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.


1996 ◽  
Vol 11 (2) ◽  
pp. 114-116 ◽  
Author(s):  
D. T. Brower ◽  
R. E. Revay ◽  
T. C. Huang

The determination of thin film thickness by four X-ray reflectivity methods (namely, the peak separation, the Fourier transform, the modified Bragg equation, and the curve-fitting methods) has been studied. An analysis of SrS and BaF2 thin films showed thickness values determined by the methods agreed to within 4%. The curve-fitting method had the highest accuracy but was time-consuming. The peak separation, the Fourier transform, and the modified Bragg equation methods are considerably faster and, on average, gave 2.8%, 0.9%, and 0.2% larger thicknesses than those of the curve-fitting method.


Author(s):  
Fabian Jaeger ◽  
Alessandro Franceschi ◽  
Holger Hoche ◽  
Peter Groche ◽  
Matthias Oechsner

AbstractCold extruded components are characterized by residual stresses, which originate from the experienced manufacturing process. For industrial applications, reproducibility and homogeneity of the final components are key aspects for an optimized quality control. Although striving to obtain identical deformation and surface conditions, fluctuation in the manufacturing parameters and contact shear conditions during the forming process may lead to variations of the spatial residual stress distribution in the final product. This could lead to a dependency of the residual stress measurement results on the relative axial and circumferential position on the sample. An attempt to examine this problem is made by the employment of design of experiments (DoE) methods. A statistical analysis of the residual stress results generated through X-Ray diffraction is performed. Additionally, the ability of cold extrusion processes to generate uniform stress states is analyzed on specimens of austenitic stainless steel 1.4404 and possible correlations with the pre-deformed condition are statistically examined. Moreover, the influence of the coating, consisting of oxalate and a MoS2 based lubricant, on the X-Ray diffraction measurements of the surface is investigated.


2010 ◽  
Vol 26 (6-8) ◽  
pp. 801-811 ◽  
Author(s):  
Mingxiao Hu ◽  
Jieqing Feng ◽  
Jianmin Zheng

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