Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

2D NMR: Overview of Homonuclear Correlation Techniques01:16

2D NMR: Overview of Homonuclear Correlation Techniques

559
Homonuclear correlation spectroscopy (COSY) is a powerful technique used in Nuclear Magnetic Resonance (NMR) spectroscopy to study the correlations between nuclei of the same type within a molecule. It provides information about scalar couplings between adjacent nuclei, which helps determine connectivity and structural information. There are several COSY variants, each with its unique strengths and experimental parameters.
COSY90 is the standard two-dimensional (2D) COSY experiment that...
559
2D NMR: Overview of Heteronuclear Correlation Techniques01:18

2D NMR: Overview of Heteronuclear Correlation Techniques

669
Heteronuclear correlation spectroscopy is an analytical technique that investigates the coupling between different types of nuclei, often a proton and an X-nucleus, such as carbon-13 or nitrogen-15. This method is commonly used in nuclear magnetic resonance (NMR) spectroscopy to gain insights into complex chemical compounds' structural and compositional aspects. A typical heteronuclear correlation spectrum displays X-nucleus chemical shifts on one axis and a proton spectrum on the other...
669
Spearman's Rank Correlation Test01:20

Spearman's Rank Correlation Test

1.3K
Spearman's rank correlation test, also known as Spearman's rho, is a nonparametric method for assessing the strength and direction of association between two variables. This test is particularly valuable when the data distribution is unknown or when the assumption of normality does not hold. Named after the English psychologist and statistician Dr. Charles Edward Spearman, it serves as the nonparametric counterpart to Pearson's correlation coefficient.
Spearman's test calculates correlation by...
1.3K
Echo01:06

Echo

826
The human ear cannot distinguish between two sources of sound if they happen to reach within a specific time interval, typically 0.1 seconds apart. More than this, and they are perceived as separate sources.
Imagine the sound is reflected back to the ears. Assuming that the source is very close to the human, the difference between hearing the two sounds—the emitted sound and the reflected sound—may be more than the minimum time for perceiving distinct sounds. If this is the case,...
826
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)01:19

2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)

1.3K
Heteronuclear single-quantum correlation spectroscopy (HSQC) is a 2D NMR technique that reveals one-bond correlations between hydrogen and a heteronucleus. The HSQC experiment is similar to the heteronuclear correlation experiment (HETCOR) but is more sensitive. In the HSQC spectrum, the proton chemical shift is plotted on the horizontal F2 axis, while the 13C chemical shift is plotted on the vertical F1 axis. The corresponding proton and 13C spectra are also shown. The HSQC contour plot does...
1.3K
2D NMR: Homonuclear Correlation Spectroscopy (COSY)01:06

2D NMR: Homonuclear Correlation Spectroscopy (COSY)

1.8K
Homonuclear correlation spectroscopy, or COSY, is a 2-dimensional NMR technique that provides information about coupled protons. Typically, the geminal and vicinal coupling are observed. For example, consider the COSY spectrum of ethyl acetate, where its 1D proton NMR spectrum is plotted along the vertical and horizontal axes with their corresponding chemical shift scale. Three spots on the diagonal corresponding to the three peaks in the 1D proton spectrum are called diagonal peaks. The COSY...
1.8K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

A pure stress formulation for modeling elastic waves using central finite differences.

The Journal of the Acoustical Society of America·2026
Same author

Interaction of elastic waves in incompressible soft materials containing weak quadratic and cubic nonlinearity.

The Journal of the Acoustical Society of America·2026
Same author

Interaction of elastic waves in solids with quadratic and cubic nonlinearity.

The Journal of the Acoustical Society of America·2023
Same author

In-process volumetric sensing of defects in multiple parts during powder bed fusion using ultrasound.

JASA express letters·2023
Same author

Stress formulation of elastic wave motion.

JASA express letters·2022
Same author

A unifying model of weakly nonlinear elastic waves; large on large theory.

The Journal of the Acoustical Society of America·2022

Related Experiment Video

Updated: Dec 27, 2025

Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population
09:02

Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population

Published on: January 31, 2025

1.4K

Higher-order spatial correlation coefficients of ultrasonic backscattering signals using partial cross-correlation

Yongfeng Song1, Christopher M Kube2, Jie Zhang3

  • 1School of Traffic and Transportation Engineering, Central South University, Changsha, Hunan 410075, China.

The Journal of the Acoustical Society of America
|March 2, 2020
PubMed
Summary

This study introduces a generalized spatial correlation coefficient (SCC) for ultrasonic backscattering signals in random media. Higher-order SCC accurately captures correlations, unlike the traditional zeroth-order method, improving material characterization.

More Related Videos

Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method
08:42

Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method

Published on: September 3, 2021

3.5K
Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels

Published on: September 8, 2016

10.7K

Related Experiment Videos

Last Updated: Dec 27, 2025

Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population
09:02

Cortical Bone Assessment Using Ultrasonic Guided Waves: A Reproducibility Study in a Healthy Population

Published on: January 31, 2025

1.4K
Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method
08:42

Measurement of the Directional Information Flow in fNIRS-Hyperscanning Data using the Partial Wavelet Transform Coherence Method

Published on: September 3, 2021

3.5K
Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels
11:34

Controlled Synthesis and Fluorescence Tracking of Highly Uniform PolyN-isopropylacrylamide Microgels

Published on: September 8, 2016

10.7K

Area of Science:

  • Ultrasonic testing
  • Materials science
  • Wave propagation in random media

Background:

  • Spatial correlation properties of ultrasonic backscattering are crucial for microstructural characterization and flaw detection.
  • Traditional spatial correlation coefficient (SCC) is limited as a leading-order quantity, neglecting confounding variables like non-zero means or odd-order moments.
  • This inadequacy hinders accurate assessment of random media's true spatial correlations.

Purpose of the Study:

  • To generalize the spatial correlation coefficient (SCC) from zeroth- to general-order using partial cross-correlation analysis.
  • To develop new indicators for quantifying SCC curves at zero time lag and maximum time shift.
  • To enhance the understanding of statistical correlations in ultrasonic backscattering signals.

Main Methods:

  • Generalization of the spatial correlation coefficient (SCC) through partial cross-correlation analysis.
  • Definition of indicators to quantify SCC curves as functions of lateral sensor separation.
  • Experimental verification using a stainless-steel specimen and focused ultrasonic transducer.

Main Results:

  • Higher-order SCC consistently captures spatial correlations in random media.
  • Zeroth-order SCC is inadequate and can lead to significant errors, predicting step sizes over six times too large.
  • The proposed method demonstrates superior performance in characterizing spatial correlations compared to traditional approaches.

Conclusions:

  • The generalized higher-order SCC provides a more accurate representation of spatial correlations in random media.
  • This advancement offers improved understanding of statistical correlations and conditions for measuring uncorrelated backscattering signals.
  • The method has significant implications for accurate microstructural characterization and flaw detection in engineering materials.