Jove
Visualize
Contact Us

Related Concept Videos

Beams with Symmetric Loadings01:15

Beams with Symmetric Loadings

548
The moment-area method is an analytical tool used in structural engineering to determine the slope and deflection of beams under various loads. Consider a cantilever with a concentrated load and moment at the free end. The first step is constructing a free-body diagram to calculate the reactions at the fixed end. Next, the bending moment diagram is plotted to visualize how the bending moment varies along the beam's length, focusing on points where the bending moment equals zero.
The M/EI...
548
Relative Motion Analysis using Rotating Axes01:25

Relative Motion Analysis using Rotating Axes

1.0K
Consider a component AB undergoing a linear motion. Along with a linear motion, point B also rotates around point A. To comprehend this complex movement, position vectors for both points A and B are established using a stationary reference frame.
However, to express the relative position of point B relative to point A, an additional frame of reference, denoted as x'y', is necessary. This additional frame not only translates but also rotates relative to the fixed frame, making it...
1.0K
Beams with Unsymmetric Loadings01:17

Beams with Unsymmetric Loadings

535
Analyzing a supported beam under unsymmetrical loadings is essential in structural engineering to understand how beams respond to varied force distributions. This analysis involves calculating the deflection and identifying points where the slope of the beam is zero, which are crucial for ensuring structural stability and functionality.
The first moment-area theorem determines the slope at any point on the beam. This theorem indicates that the change in slope between two points on a beam...
535
Relative Motion Analysis using Rotating Axes-Problem Solving01:29

Relative Motion Analysis using Rotating Axes-Problem Solving

839
Consider a crane whose telescopic boom rotates with an angular velocity of 0.04 rad/s and angular acceleration of 0.02 rad/s2. Along with the rotation, the boom also extends linearly with a uniform speed of 5 m/s. The extension of the boom is measured at point D, which is measured with respect to the fixed point C on the other end of the boom. For the given instant, the distance between points C and D is 60 meters.
Here, in order to determine the magnitude of velocity and acceleration for point...
839
Moment-of-Momentum Equation01:09

Moment-of-Momentum Equation

575
The moment-of-momentum equation is a critical tool for analyzing the torque produced by the rotating blades of a wind turbine. This equation is derived by applying Newton's second law to a fluid particle, which states that the rate of change of linear momentum is equal to the external force acting on the particle.
575
Shear and Bending Moment Diagram: Problem Solving01:24

Shear and Bending Moment Diagram: Problem Solving

3.9K
When analyzing a beam supporting concentrated loads and a distributed load, drawing the shear and bending moment diagrams is essential. These diagrams help understand the internal forces and moments acting on the beam, which is crucial for designing safe and efficient structures. Follow these steps to create the shear and bending moment diagrams:
Draw a Free-Body Diagram: Start by drawing a free-body diagram of the entire beam, including the concentrated loads, distributed load, and reaction...
3.9K

You might also read

Related Articles

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

Sort by
Same author

Moment analysis of focus-diverse point spread functions for modal wavefront sensing of uniformly illuminated circular-pupil systems.

Optics letters·2011
Same author

Optimal collimation of misaligned optical systems by concentering primary field aberrations.

Optics express·2010
Same author

Use of Zernike polynomials for efficient estimation of orthonormal aberration coefficients over variable noncircular pupils.

Optics letters·2010
Same author

Computer-guided alignment II :Optical system alignment using differential wavefront sampling.

Optics express·2009
Same author

Computer-guided alignment I : Phase and amplitude modulation of alignment-influenced optical wavefront.

Optics express·2009
Same author

Computer-guided alignment III: description of inter-element alignment effect in circular-pupil optical systems.

Optics express·2008
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 Experiment Video

Updated: May 1, 2026

Lens-free Video Microscopy for the Dynamic and Quantitative Analysis of Adherent Cell Culture
09:04

Lens-free Video Microscopy for the Dynamic and Quantitative Analysis of Adherent Cell Culture

Published on: February 23, 2018

9.1K

Error analysis of moment-based modal wavefront sensing.

Hanshin Lee

    Optics Letters
    |April 3, 2014
    PubMed
    Summary

    Moment-based wavefront sensing quantifies aberration modes using point spread function (PSF) shape. This method offers accuracy comparable to wavefront sensors, with analytically described errors from pixelation and noise.

    Area of Science:

    • Optical Engineering
    • Image Analysis
    • Aberration Analysis

    Background:

    • Point spread function (PSF) shape analysis offers a visual assessment of optical aberration modes.
    • Shape moments provide a quantitative method for modal coefficient estimation, rivaling traditional wavefront sensors.

    Purpose of the Study:

    • To analytically describe the error in moment-based wavefront sensing.
    • To investigate the impact of pixelation and photon/readout noise on estimation accuracy.

    Main Methods:

    • Utilized shape moments of focus-modulated point spread functions (PSFs).
    • Developed analytical models for moment-based wavefront sensing error.
    • Employed numerical simulations to validate the models.

    Main Results:

    More Related Videos

    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

    1.7K
    Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing
    08:54

    Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing

    Published on: February 13, 2018

    8.1K

    Related Experiment Videos

    Last Updated: May 1, 2026

    Lens-free Video Microscopy for the Dynamic and Quantitative Analysis of Adherent Cell Culture
    09:04

    Lens-free Video Microscopy for the Dynamic and Quantitative Analysis of Adherent Cell Culture

    Published on: February 23, 2018

    9.1K
    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

    1.7K
    Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing
    08:54

    Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing

    Published on: February 13, 2018

    8.1K
    • Moment-based wavefront sensing accuracy is comparable to conventional wavefront sensors.
    • Analytical models accurately predict modal estimation error.
    • Error components are dependent on PSF shape but estimable from measured PSFs.

    Conclusions:

    • Moment-based wavefront sensing is a viable technique for aberration analysis.
    • The developed error models provide insights into the limitations and performance of this method.
    • Accurate estimation is achievable with sufficient spatial resolution and photon counts.