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

Relative Motion Analysis - Acceleration01:10

Relative Motion Analysis - Acceleration

1.1K
A slider-crank mechanism converts rotational motion from the crank into linear motion of the slider or vice versa. This mechanism consists of three main parts: the crank, the connecting rod, and the slider. The movement of the slider-crank is an example of general plane motion as the fluctuating angle between the crank and the connecting rod. Consider a segment AB where point A is at the end of the slider and point B is on the diametrically opposite end to point A, on a crack. The variance in...
1.1K
Curvilinear Motion: Rectangular Components01:23

Curvilinear Motion: Rectangular Components

1.6K
Curvilinear motion characterizes the movement of a particle or object along a curved path, notably evident when envisioning a car navigating a winding road. If the car starts at point A, its position vector is established within a fixed frame of reference, where the ratio of the position vector to its magnitude signifies the unit vector pointing in the position vector's direction.
As the car advances, its position evolves over time. Quantifying the car's velocity involves computing the...
1.6K
Relative Motion Analysis using Rotating Axes - Acceleration01:22

Relative Motion Analysis using Rotating Axes - Acceleration

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. The absolute velocity of point B is determined by adding the absolute velocity of point A, the relative velocity of point B in the rotating frame, and the effects caused by the angular velocity within the rotating frame.
Time differentiation is...
1.0K
Application of Linearization and Approximation01:29

Application of Linearization and Approximation

193
A drone flying through complex terrain often relies on more than one sensing method to estimate small changes in altitude. Along with direct measurements, air pressure provides a useful indirect indicator of vertical movement. Atmospheric pressure decreases as altitude increases, and this relationship is commonly described using an exponential model. Although accurate, converting pressure measurements into altitude values requires calculations that are too complex to perform repeatedly during...
193
Acceleration Vectors01:30

Acceleration Vectors

19.6K
In everyday conversation, accelerating means speeding up. Acceleration is a vector in the same direction as the change in velocity, Δv, therefore the greater the acceleration, the greater the change in velocity over a given time. Since velocity is a vector, it can change in magnitude, direction, or both. Thus acceleration is a change in speed or direction, or both. For example, if a runner traveling at 10 km/h due east slows to a stop, reverses direction, and continues their run at 10 km/h...
19.6K
Mechanistic Models: Compartment Models in Algorithms for Numerical Problem Solving01:29

Mechanistic Models: Compartment Models in Algorithms for Numerical Problem Solving

438
Mechanistic models play a crucial role in algorithms for numerical problem-solving, particularly in nonlinear mixed effects modeling (NMEM). These models aim to minimize specific objective functions by evaluating various parameter estimates, leading to the development of systematic algorithms. In some cases, linearization techniques approximate the model using linear equations.
In individual population analyses, different algorithms are employed, such as Cauchy's method, which uses a...
438

You might also read

Related Articles

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

Sort by
Same author

Preclinical magnetic resonance imaging in the presence of Alpha-DaRT seeds: mitigation of metal artifacts.

Biomedical physics & engineering express·2026
Same author

OPTIKS: Optimized Gradient Properties Through Timing in k-Space.

IEEE transactions on medical imaging·2025
Same author

A Flexible Approach for Fat-Water Separation With Bipolar Readouts and Correction of Gradient-Induced Phase and Amplitude Effects.

Magnetic resonance in medicine·2025
Same author

Editorial for "Assessing the Impact of Imaging Parameters on MRI Measurement of Kidney T2".

Journal of magnetic resonance imaging : JMRI·2025
Same author

The hierarchy of hazard controls in clinical magnetic resonance safety: an analysis of the American College of Radiology Manual on MR Safety.

Current problems in diagnostic radiology·2025
Same author

Using deep feature distances for evaluating the perceptual quality of MR image reconstructions.

Magnetic resonance in medicine·2025
Same journal

A Comparison of Tissue Property Values Estimated Using Conventional Cardiac MRF and MT-Cardiac MRF.

Magnetic resonance in medicine·2026
Same journal

Dependence of the Extra-Cellular Diffusion Coefficient on the Fractions of Neurites and Cell Bodies in Gray Matter.

Magnetic resonance in medicine·2026
Same journal

Triple-Pulse <sup>23</sup>Na MRI Sequence (TriNa) for Simultaneous Acquisition of Spin-Density-Weighted and Fluid-Attenuated Images.

Magnetic resonance in medicine·2026
Same journal

Evaluation of Phantom Doping Materials in Quantitative Susceptibility Mapping.

Magnetic resonance in medicine·2026
Same journal

Design of an 8-Channel Transmit 32-Channel Receive 11.7T Head Coil and Evaluation of SNR Gains.

Magnetic resonance in medicine·2026
Same journal

The Potential for Absolute Temperature Imaging Based on Brain Metabolites Using an FID-Shifting Approach in Gradient Echo Planar Spectroscopic Imaging (GREPSI).

Magnetic resonance in medicine·2026
See all related articles

Related Experiment Video

Updated: May 3, 2026

Assessing Cerebral Autoregulation via Oscillatory Lower Body Negative Pressure and Projection Pursuit Regression
11:26

Assessing Cerebral Autoregulation via Oscillatory Lower Body Negative Pressure and Projection Pursuit Regression

Published on: December 10, 2014

13.0K

Accelerating parameter mapping with a locally low rank constraint.

Tao Zhang1, John M Pauly, Ives R Levesque

  • 1Department of Electrical Engineering, Magnetic Resonance Systems Research Laboratory, Stanford University, Stanford, California, USA.

Magnetic Resonance in Medicine
|February 7, 2014
PubMed
Summary
This summary is machine-generated.

Accelerated MR parameter mapping is achieved using a locally low rank (LLR) constraint. Combining LLR with parallel imaging further enhances performance, especially for highly accelerated scans, improving accuracy in T1 and T2 mapping.

Keywords:
compressed sensinglow rankparallel imagingparameter mappingquantitative MRI

More Related Videos

Design and Application of a Fault Detection Method Based on Adaptive Filters and Rotational Speed Estimation for an Electro-Hydrostatic Actuator
06:45

Design and Application of a Fault Detection Method Based on Adaptive Filters and Rotational Speed Estimation for an Electro-Hydrostatic Actuator

Published on: October 28, 2022

1.7K

Related Experiment Videos

Last Updated: May 3, 2026

Assessing Cerebral Autoregulation via Oscillatory Lower Body Negative Pressure and Projection Pursuit Regression
11:26

Assessing Cerebral Autoregulation via Oscillatory Lower Body Negative Pressure and Projection Pursuit Regression

Published on: December 10, 2014

13.0K
Design and Application of a Fault Detection Method Based on Adaptive Filters and Rotational Speed Estimation for an Electro-Hydrostatic Actuator
06:45

Design and Application of a Fault Detection Method Based on Adaptive Filters and Rotational Speed Estimation for an Electro-Hydrostatic Actuator

Published on: October 28, 2022

1.7K

Area of Science:

  • Magnetic Resonance Imaging (MRI)
  • Medical Physics
  • Biomedical Engineering

Background:

  • MR parameter mapping (e.g., T1, T2) is crucial for quantitative diagnostics.
  • Traditional methods are time-consuming, limiting clinical application.
  • Accelerated acquisition techniques are needed to improve efficiency.

Purpose of the Study:

  • To develop and evaluate a locally low rank (LLR) constraint for accelerating MR parameter mapping.
  • To investigate the combined use of LLR and parallel imaging for enhanced acceleration.
  • To assess the accuracy and performance of these methods in T1 and T2 mapping.

Main Methods:

  • Developed an LLR method for MR parameter mapping.
  • Compared LLR with a globally low rank method in T2 mapping.
  • Proposed and evaluated a combined LLR and parallel imaging method for T1 mapping with high acceleration factors.

Main Results:

  • LLR method showed higher accuracy than globally low rank for T2 mapping at acceleration factors 2 and 3.
  • The combined LLR and parallel imaging method achieved T1 mapping with a normalized root mean square error of 0.025 at a 6x acceleration factor.
  • The proposed method demonstrated superior performance compared to individual techniques.

Conclusions:

  • LLR constraint is superior to globally low rank methods for MR parameter mapping.
  • The combined LLR and parallel imaging approach offers significant advantages for highly accelerated MR acquisitions.
  • This technique holds promise for faster and more efficient quantitative MRI.