scholarly journals Automation of the Peak Fitting Method in Bone FTIR Microspectroscopy Spectrum Analysis: Human and Mice Bone Study

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Marc Gardegaront ◽  
Delphine Farlay ◽  
Olivier Peyruchaud ◽  
Hélène Follet
Keyword(s):  
Spectrum Analysis ◽  
Nondestructive Method ◽  
Automatic Process ◽  
Ftir Microspectroscopy ◽  
Analysis Process ◽  
Peak Fitting ◽  
Fitting Method ◽  
Rigorous Framework ◽  
Thin Bone ◽  
Boundary Limits

FTIR microspectroscopy (FTIRM) is a commonly used nondestructive method to characterise thin bone sections. However, spectrum analysis methods are often highly sensitive to small variations (e.g., boundary limits), thus implying a time-consuming and redundant analysis process. To solve this issue, software has been developed based on several algorithms to automate the analysis. Furthermore, a rigorous framework has been established concerning the peak fitting method to obtain the systematic best potential solution. Validation of the automatic method has been performed by comparison with the manual method. Results and validation proved the reliability of the automatic process. The developed algorithms provide the means necessary to fully compare the results between bone FTIRM studies and between different laboratories.

A new peak fitting method for 1D solid-state 29Si NMR spectra based on singular spectrum analysis

2019 ◽  
Vol 18 (01) ◽  
pp. 1941014
Author(s):  
Guiliang Li ◽  
Changjun Li ◽  
Nan Wei
Keyword(s):  
Molecular Structure ◽  
Spectrum Analysis ◽  
Nmr Spectra ◽  
Singular Spectrum Analysis ◽  
Embedding Dimension ◽  
Characteristic Peak ◽  
Gaussian Fitting ◽  
Singular Spectrum ◽  
Peak Fitting ◽  
Fitting Method

[Formula: see text]Si Nuclear Magnetic Resonance (NMR) can measure the molecular structure of silicate in oilfield reinjection water. However, noise in [Formula: see text]Si NMR spectra (NMRS) affects the determination of silicate molecular structure type. To solve this problem, a new peak fitting method (Two-step Greedy-Singular Spectrum Analysis-Gaussian Fitting Method, TSG-SSA-GFM) is proposed in this paper. This method first uses TSG to determine the embedding dimension, then uses SSA to determine the characteristic peak position. Finally, GFM is used to calculate the molar ratio of characteristic peaks. The results show that TSG can quickly determine the embedding dimension and reduce computation by at least 50% vs. the global ergodic method. The mean deviation of characteristic peak positions determined by SSA is 0.07 ppm, while Discrete Wavelet Transform (DWT) and Empirical Mode Decomposition (EMD) cannot determine characteristic peaks of [Formula: see text]Si NMRS containing overlapping peak. The average [Formula: see text]-squared of Gaussian fitting of [Formula: see text]Si NMRS is 98.4% while Lorentzian is 90.6%. Therefore, this study provides an important method for quantitative analysis of [Formula: see text]Si NMRS.

scholarly journals Cascaded-Microrings Biosensors Fabricated on a Polymer Platform

Sensors ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 181 ◽  
Author(s):  
Yuxin Liang ◽  
Qi Liu ◽  
Zhenlin Wu ◽  
Geert Morthier ◽  
Mingshan Zhao
Keyword(s):  
Free Spectral Range ◽  
Volume Ratio ◽  
Cost Effective ◽  
Spectral Shift ◽  
Microring Resonators ◽  
Optical Polymer ◽  
Peak Fitting ◽  
Fitting Method ◽  
Infrared Wavelengths ◽  
Vernier Effect

Polymer-based single-microring biosensors usually have a small free spectral range (FSR) that hampers the tracing of the spectrum shifting in the measurement. A cascade of two microring resonators based on the Vernier effect, is applied in this article in order to make up for this defect. A small FSR difference between the reference microring and the sensing microring is designed, in order to superpose the periodic envelope signal onto the constituent peaks, which makes it possible to continuously track the spectrum of the sensor. The optical polymer material, Ormocore, which has a large transparent window, is used in the fabrication. The biosensor is fabricated by using an UV-based soft imprint technique, which is considered to be cost-effective and suitable for mass production. By optimizing the volume ratio of Ormocore and the maT thinner, the device can be fabricated almost without a residual layer. The device works at a wavelength of 840 nm, where water absorption loss is much lower than at the infrared wavelengths. A two-step fitting method, including single-peak fitting and whole-envelope fitting, is applied in order to trace the spectral shift accurately. Finally, the two-cascaded-microrings biosensor is characterized, and the obtained FSR is 4.6 nm, which is 16 times larger than the FSR of the single microring biosensor demonstrated in our previous work. Moreover, the sensitivity can also be amplified by 16-fold, thanks to the Vernier effect.

A Study of the Peak Boundary Method and Effect Evaluation Based on NaI(TI) Detector for γ-Spectrum Analysis

2013 ◽  
Vol 347-350 ◽  
pp. 1006-1011
Author(s):  
Yao Zong Yang ◽  
Fang Fang ◽  
Jian Feng He ◽  
Jun Jun Ran
Keyword(s):  
Spectrum Analysis ◽  
Gaussian Function ◽  
Comparison Method ◽  
Convergence Result ◽  
Weighting Factor ◽  
Gamma Energy ◽  
Common Boundary ◽  
Function Fitting ◽  
Qualitative Detection ◽  
Fitting Method

In order to accurately analyze the result, which comes from quantitative and qualitative detection based on gamma energy spectrum of NaI(T1) detector, peak boundary has become one of the main factors which influence the spectrum analysis. By implementing some common boundary determining algorithms in the Matlab such as simple comparison method, derivative method, symmetry zero-area method, the full width method and gaussian function fitting method, as well as comparing effectiveness among those algorithm, priority of those boundary algorithms is evaluated. At the same time, because the boundary determining algorithm based on traditional gaussian fitting is not ideal, the new boundary determining algorithm based on the least squares fitting of gaussian function with weighting factor is proposed. The practice verifies that this method is stability and can obtain preferable convergence result in boundary determining of unimodal or combination peaks.

scholarly journals Assessment of Thermal Maturity Trends in Devonian–Mississippian Source Rocks Using Raman Spectroscopy: Limitations of Peak-Fitting Method

2017 ◽  
Vol 5 ◽  
Author(s):  
Jason S. Lupoi ◽  
Luke P. Fritz ◽  
Thomas M. Parris ◽  
Paul C. Hackley ◽  
Logan Solotky ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Source Rocks ◽  
Thermal Maturity ◽  
Peak Fitting ◽  
Fitting Method

Studying on the Magnetorheological Fluids and its Rheometer

2011 ◽  
Vol 230-232 ◽  
pp. 1396-1401 ◽  
Author(s):  
Bing San Chen ◽  
Ji Bin Jiang ◽  
Fu Jiang Zhang
Keyword(s):  
Dynamic Characteristics ◽  
Spectrum Analysis ◽  
Computer Software ◽  
High Order ◽  
Step Motor ◽  
Order Analysis ◽  
Analysis Process ◽  
Mr Fluids ◽  
Order Spectrum ◽  
Measurement And Analysis

This paper presents a magnetorheological(MR) rheometer which consists of a pair of rotating parallel disc, step motor, the signal collecting device, computer software for dynamic analysis etc.. In order to assess the performance of the MR rheometer, high-order spectrum analysis tools are used. The theoretical and experimental results indicate that the rheometer is useful to test the dynamic charicteristics of the MR fluids and the high-order analysis might be helpful to describe MR rheometer dynamic characteristics. The measurement and analysis process based on virtual instruments are automatically controlled by computer in this paper.

scholarly journals Optimization of Single Voxel MR Spectroscopy Sequence Parameters and Data Analysis Methods for Thermometry in Deep Hyperthermia Treatments

2016 ◽  
Vol 16 (4) ◽  
pp. 470-481 ◽  
Author(s):  
J. Hartmann ◽  
J. Gellermann ◽  
T. Brandt ◽  
M. Schmidt ◽  
S. Pyatykh ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Parameter Optimization ◽  
Flip Angle ◽  
Resonance Spectroscopy ◽  
Magnetic Resonance Imaging System ◽  
Peak Fitting ◽  
Fitting Method ◽  
Echo Time ◽  
Deep Hyperthermia

Objective: The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic resonance spectroscopy sequence (point-resolved spectroscopy) parameter optimization that enables thermometry during deep hyperthermia treatments. Materials and Methods: Different Lorentz peak-fitting methods and a peak finding method using singular value decomposition of a Hankel matrix were compared. Phantom measurements on organic substances (mayonnaise and pork) were performed inside the hyperthermia 1.5-T magnetic resonance imaging system for the parameter optimization study. Parameter settings such as voxel size, echo time, and flip angle were varied and investigated. Results: Usually all peak analyzing methods were applicable. Lorentz peak-fitting method in MATLAB proved to be the most stable regardless of the number of fitted peaks, yet the slowest method. The examinations yielded an optimal parameter combination of 8 cm3 voxel volume, 55 millisecond echo time, and a 90° excitation pulse flip angle. Conclusion: The Lorentz peak-fitting method in MATLAB was the most reliable peak analyzing method. Measurements in homogeneous and heterogeneous phantoms resulted in optimized parameters for the magnetic resonance spectroscopy sequence for thermometry.

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