Strain Analysis Method Research Articles

Implementation of a visualization teaching approach for mechanical analysis in civil engineering structures

AbstractThe visualization method for mechanics knowledge in civil engineering courses is very important, which can help students learn abstract mechanics. Combined with the structural analysis software, this paper develops a visualization teaching approach for mechanical analysis in civil engineering structures based on the proposed deformation decomposition method, such as elastic mechanics, material mechanics and structural dynamics. Compared with traditional strain analysis method, the proposed method is more intuitive and can identify more macroscopic basic deformations. By aid of a survey for undergraduate students and master students, the teaching effectiveness of the visualization course is higher than that of the blackboard writing course. Besides, Mann–Whitney test results show that there is a significant difference. The proportion of undergraduate students that think the combination of visualization has good effects are greater than those of master students. The proposed visualization teaching approach can be promoted in mechanics courses of civil engineering.

Extended Caking Method for Strain Analysis of Polycrystalline Diffraction Debye–Scherrer Rings

Extended Caking Method for Strain Analysis of Polycrystalline Diffraction Debye–Scherrer Rings

Atomic‐scale strain analysis for advanced Si/SiGe heterostructure by using transmission electron microscopy

AbstractThree‐dimensional stacked transistors based on Si/SiGe heterojunction are a potential candidate for future low‐power and high‐performance computing in integrated circuits. Observing and accurately measuring strain in Si/SiGe heterojunctions is critical to increasing carrier mobility and improving device performance. Transmission electron microscopy (TEM) with high spatial resolution and analytical capabilities provides technical support for atomic‐scale strain measurement and promotes significant progress in strain mapping technology. This paper reviews atomic‐scale strain analysis for advanced Si/SiGe heterostructure based on TEM techniques. Convergent‐beam electron diffraction, nano‐beam electron diffraction, dark‐field electron holography, and high‐resolution TEM with geometrical phase analysis, are comprehensively discussed in terms of spatial resolution, strain precision, field of view, reference position, and data processing. Also, the advantages and critical issues of these strain analysis methods based on the TEM technique are summarized, and the future direction of TEM techniques in the related areas is prospected.

Bending creep behaviour of various polymer films analysed by surface strain measurement.

Understanding the temporal bending deformation of polymer films is key to designing mechanically durable flexible electronic devices. However, such creep behaviour under persistent bending remains unclear due to a lack of precise and accurate bending strain analysis methods. Herein, we quantitatively analysed the bending creep behaviour of various polymeric films using our developed strain measurement method that can precisely measure surface strain from optical diffraction. The surface strain measurement reveals that bending creep deformation differs depending on the polymer structure. The four-element Burgers model was employed to model the temporal strain increase on the bending surface successfully. By fitting the four-element model to the time course of the measured surface strain, we found that each polymer film has a different threshold surface strain for the appearance of bending creep deformation. Such disparity in the bending creep behaviour can be explained by the difference in strain energy density between the polymer films and their elastic model; polymer films with a small strain energy density difference show small bending creep deformation. The results obtained in this study contribute to the elucidation of the bending creep behaviour of polymer films and the development of flexible electronic devices operated under persistent bending.

Abstract 14417: Regional 4D Cardiac Magnetic Resonance Strain Associates With Late Gadolinium Enhancement in Duchenne Muscular Dystrophy Associated Cardiomyopathy

Introduction: Cardiomyopathy (CM) is the leading cause of death in Duchenne muscular dystrophy (DMD). Onset and clinical progression are varied. Cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) can detect fibrofatty replacement prior to decreased left ventricular ejection fraction (LVEF) but requires administration of gadolinium contrast agents. Non-contrast methods to characterize CM onset and progression could decrease scan time and exposure to gadolinium. Using a novel 4D (3D+time) regional strain analysis method, we hypothesized that the regional magnitude of surface area strain (E a ) would be significantly decreased in DMD patients with LGE and that E a would correlate with decreased LVEF . Methods: Short-axis cine CMR images for 43 pediatric DMD patients (13.6 ± 4.2 years) were compiled into 4D sequences for regional strain analysis (Fig. 1A). For all 4D sequences, epi- and endocardial borders were segmented across one cardiac cycle for kinematic analysis using a custom-built MATLAB graphical user interface (MathWorks, Natick, MA). Regional E a was measured by determining the relative change in the localized 4D endocardial surface mesh compared to end-diastole. Unpaired t-test and Spearman’s rho were used to determine statistical significance and correlation. Results: DMD patients had a range of CM severity: 13 with reduced LVEF of <55% (30% of total) and 28 with LGE (65% of total). Peak E a was significantly different between patients with and without LGE in the basal inferior ( p =0.022), basal inferolateral ( p <0.001), basal anterolateral ( p =0.002), mid inferolateral ( p =0.004), mid anterolateral ( p =0.018), and apical anterior ( p <0.032), regions (Fig.1B). Basal E a also correlated significantly with LVEF ( rho =-0.45, p< 0.001; Fig. 1C). Conclusion: Regional E a from 4D CMR in DMD was reduced in patients with LGE compared to those without LGE particularly in the basolateral regions. Peak basal E a correlated with a reduction in LVEF. LVEF.

Consistent C-bar radial-basis Galerkin method for finite strain analysis

For finite-strain problems of quasi-incompressible materials, with hyperelastic and hyperelasto-plastic behavior, we develop a mixed polynomial-enriched radial-basis function (RBF) interpolation. It is characterized by decoupling quadrature and polynomials for the deviatoric and volumetric terms of the right Cauchy–Green tensor. With an enriched interpolation, first and second derivatives of the deformation gradient are continuous. A finite-element mesh is employed for quadrature purposes with the corresponding distribution of Gauss points. In terms of discretization, linear, quadratic and cubic polynomials are combined and function support is established from the number of pre-assigned nodes. Due to the adoption of a Lagrangian kernel, finite strain elasto-plastic constitutive developments are based on the Mandel stress. Combined with the C¯ technique, these developments are found to be convenient from an implementation perspective, as RBF formulations for finite strain plasticity have been limited in terms of generality and amplitude of deformations in the quasi-incompressibility case. Three benchmark tests are successfully solved, and it was found that a combination of reduced integration with a deviatoric cubic basis and volumetric quadratic basis provides superior results in the quasi-incompressible case. Numerical testing shows very good convergence behavior of the results. Besides absence of locking with selective interpolation, outstanding Newton convergence was observed regardless of strain levels.

Study of the Finite Strain of Bekhme Structure in Shaqlawa Area, Northeastern Iraq

This research includes the finite deformation study from five oriented samples of the sandstone rocks for the Injana Formation. in the SW flank of Bekhme Anticline in NE Iraq. Analysis and measurement of the finite deformation were carried out on sandstone beds that are mostly of continental environments. This work is based on the Fry method for strain analysis. The calculated strain was illustrated, in the form of ellipsoids, within three prepared orthogonal single surfaces in a single type, as well as, the method was used to estimate the ratio of the strain for these types of samples. The finite deformation in the study area is not considered high, this was mainly because the sandstone rock samples undergo brittle strain during the faulting and the folding. The computed ratios of strain, (3-D trend for deformation axes) of deformation rocks were equivalence to the Flinn chart that is usually used for plotting deformation ellipsoids, and accordingly method of stereographical projection, the maximum axis for that ellipsoid was parallel to the measured Bekhme Anticline axis and minimum axis was orthogonal to the axis of Bekhme Anticline in the studied region. This trend of those axes was related to the Arabian Plate movement.

A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment pressure. Moreover, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

Method of strain analysis of pipelines under landslides: An improved semi-analytical method for softening bending moment-curvature

The accurate description of the elastic‒plastic stress‒strain of a pipeline is used to evaluate the risk that the pipeline will undergo failure during a landslide. This paper proposes a complete set of refined semi-analytical methods (SAMs) for pipeline elastic-plastic strain to accurately evaluate the safety of pipelines. First, a concise model for the calculation of landslide thrust is established based on the pipe-soil interaction mechanism as load boundaries of the SAMs. Secondly, the plastic softening bending moment-curvature relationship (BMCR) is derived to establish a difference equation for the deformation of the pipeline during the plastic stage based on the principle of internal force balance of the pipe section, and then the bending plastic strain is calculated accurately. Finally, the axial strain is fully calculated considering the interaction between axial force and bending of the pipeline. The comparison of the results of small-scale landslide tests, large-scale landslide tests, and SAM calculations shows that the improved SAM has good applicability, with 20% better accuracy than traditional methods. In conclusion, the SAM proposed in this paper can effectively guide the design and evaluation of the strain-based design pipeline.

Voxel‐Based Full‐Field Eigenstrain Reconstruction of Residual Stresses

Inverse eigenstrain (inherent strain) analysis methods are shown to be effective for the reconstruction of residual stresses in plane eigenstrain problems (continuously processed bodies) while conversely residual stress reconstruction in discontinuously processed bodies is extremely challenging and necessitates the use of complex regularizing assumptions. Herein, a new generic inverse eigenstrain method suitable for the reconstruction of residual stresses along with residual elastic strains and displacements in discontinuously processed bodies is introduced. The proposed method uses the superposition of eigenstrain radial basis functions together with a set of limited experimental data for model‐free (unconstrained) determination of unknown eigenstrain fields. This approach eliminates the limitations introduced by global basis functions such as polynomials. The novel point of this method is the ability to account for all six components of strain in an isotropic body without using regularizing assumptions. By lifting complex guiding formulation, the fidelity of full‐field eigenstrain reconstruction becomes directly related to the quality of experimental data and proper discretisation of the model domain. The FEniCS implementation has been validated using the experimental data of pointwise high‐energy synchrotron X‐ray diffraction measurements from a bent titanium alloy bar. A hybrid high throughput computing approach is also introduced for effective parallel computing.

INTEGRATION OF LINEAMENT AND STRAIN ANALYSIS TO ASSESS LANDSLIDE VULNERABILITY ALONG TAIPING TO IPOH HIGHWAY, MALAYSIA

Abstract. The overall tectonics of a terrain and landslide occurrences can be controlled using lineament analysis. In addition, understanding the deformational characteristics of the rocks in question cannot be overemphasized. The current work was carried out along Taiping to Ipoh stretch of the North – South PLUS Highway Malaysia and its environs to assess landslide vulnerability via lineaments and strain deformation analysis. Approximately 73 km stretch of the road was analysed. Classification of about 197 lineaments was done from very high to very low density classes applying class break procedures to signify their respective risk zones. Fry strain analysis method was then integrated by digitizing the centre of the grains from which reference lines angles and axial ratios of 16 photomicrographs of various lithologies obtained from field investigations were used to understand their strain deformational pattern. The lineament intersection point map shows its concordance with the strain ellipsoid. The major trend of the lineaments and fry strain ellipsoid were both found to be trending NE–SW. Congruity between the lineaments intersection density and the flattened higher degree of strain signified a risk prone zone and probable landslide trigger along the highway.

Localized strain characterization of cardiomyopathy in Duchenne muscular dystrophy using novel 4D kinematic analysis of cine cardiovascular magnetic resonance

BackgroundCardiomyopathy (CMP) is the most common cause of mortality in Duchenne muscular dystrophy (DMD), though the age of onset and clinical progression vary. We applied a novel 4D (3D + time) strain analysis method using cine cardiovascular magnetic resonance (CMR) imaging data to determine if localized strain metrics derived from 4D image analysis would be sensitive and specific for characterizing DMD CMP. MethodsWe analyzed short-axis cine CMR image stacks from 43 DMD patients (median age: 12.23 yrs [10.6–16.5]; [interquartile range]) and 25 male healthy controls (median age: 16.2 yrs [13.3–20.7]). A subset of 25 male DMD patients age-matched to the controls (median age: 15.7 yrs [14.0-17.8]) was used for comparative metrics. CMR images were compiled into 4D sequences for feature-tracking strain analysis using custom-built software. Unpaired t-test and receiver operator characteristic area under the curve (AUC) analysis were used to determine statistical significance. Spearman's rho was used to determine correlation. ResultsDMD patients had a range of CMP severity: 15 (35% of total) had left ventricular ejection fraction (LVEF) > 55% with no findings of myocardial late gadolinium enhancement (LGE), 15 (35%) had findings of LGE with LVEF > 55% and 13 (30%) had LGE with LVEF < 55%. The magnitude of the peak basal circumferential strain, basal radial strain, and basal surface area strain were all significantly decreased in DMD patients relative to healthy controls (p < 0.001) with AUC values of 0.80, 0.89, and 0.84 respectively for peak strain and 0.96, 0.91, and 0.98 respectively for systolic strain rate. Peak basal radial strain, basal radial systolic strain rate, and basal circumferential systolic strain rate magnitude values were also significantly decreased in mild CMP (No LGE, LVEF > 55%) compared to a healthy control group (p< 0.001 for all). Surface area strain significantly correlated with LVEF and extracellular volume (ECV) respectively in the basal (rho = − 0.45, 0.40), mid (rho = − 0.46, 0.46), and apical (rho = − 0.42, 0.47) regions. ConclusionStrain analysis of 3D cine CMR images in DMD CMP patients generates localized kinematic parameters that strongly differentiate disease from control and correlate with LVEF and ECV.

Evaluation method of surrounding rock stability: Failure approach index theory of strain limit analysis for engineering applications.

In general, the ultimate parameter selection method of the failure approach index theory among the three-dimensional problems in geotechnical engineering is unclear in theory, and the symbol convention of the failure approach index in engineering calculation is contrary to the stipulation of the numerical simulation software. Hence, the values of the ultimate plastic shear strain are difficult to determine. To solve this problem, the criterion of positive tension and negative compression and the sequence of the principal stress σ1 ≤ σ2 ≤ σ3 are defined in this paper, and the expression of Mohr-Coulomb yield approach index id deduced. Under the condition of the principal strain sequence ε1 ≤ ε2 ≤ ε3, the formula of the ultimate shear strain is derived using the method of the ultimate strain analysis so as to obtain the simple expression and calculation method of the ultimate plastic shear strain, which has provided the calculation parameters for the three-dimensional ultimate plastic shear strain in the Mohr-Coulomb strain softening model and improved the failure approach index theory. In the light of the aforementioned theory, the ultimate strains of cubic concrete specimens are analyzed, and the obtained ultimate strain values are found consistent with previous research findings, which verifies the correctness and reliability of the ultimate strain analysis method. In addition, it is applied to the quantitative elastic-plastic failure analysis of the section coal pillar in Hengjin coal industry for determining its reasonable retainment width. Consequently, the research results can be embraced as the theoretical basis for the stability analysis of geotechnical materials and exhibits engineering application potential.

Myocardial strain analysis of echocardiography based on deep learning.

Strain analysis provides more thorough spatiotemporal signatures for myocardial contraction, which is helpful for early detection of cardiac insufficiency. The use of deep learning (DL) to automatically measure myocardial strain from echocardiogram videos has garnered recent attention. However, the development of key techniques including segmentation and motion estimation remains a challenge. In this work, we developed a novel DL-based framework for myocardial segmentation and motion estimation to generate strain measures from echocardiogram videos. Three-dimensional (3D) Convolutional Neural Network (CNN) was developed for myocardial segmentation and optical flow network for motion estimation. The segmentation network was used to define the region of interest (ROI), and the optical flow network was used to estimate the pixel motion in the ROI. We performed a model architecture search to identify the optimal base architecture for motion estimation. The final workflow design and associated hyperparameters are the result of a careful implementation. In addition, we compared the DL model with a traditional speck tracking algorithm on an independent, external clinical data. Each video was double-blind measured by an ultrasound expert and a DL expert using speck tracking echocardiography (STE) and DL method, respectively. The DL method successfully performed automatic segmentation, motion estimation, and global longitudinal strain (GLS) measurements in all examinations. The 3D segmentation has better spatio-temporal smoothness, average dice correlation reaches 0.82, and the effect of target frame is better than that of previous 2D networks. The best motion estimation network achieved an average end-point error of 0.05 ± 0.03 mm per frame, better than previously reported state-of-the-art. The DL method showed no significant difference relative to the traditional method in GLS measurement, Spearman correlation of 0.90 (p < 0.001) and mean bias -1.2 ± 1.5%. In conclusion, our method exhibits better segmentation and motion estimation performance and demonstrates the feasibility of DL method for automatic strain analysis. The DL approach helps reduce time consumption and human effort, which holds great promise for translational research and precision medicine efforts.

Statistical and Computational Methods for Microbial Strain Analysis.

Microbial strains are interpreted as a lineage derived from a recent ancestor that have not experienced "too many" recombination events and can be successfully retrieved with culture-independent techniques using metagenomic sequencing. Such a strain variability has been increasingly shown to display additional phenotypic heterogeneities that affect host health, such as virulence, transmissibility, and antibiotics resistance. New statistical and computational methods have recently been developed to track the strains in samples based on shotgun metagenomics data either based on reference genome sequences or Metagenome-assembled genomes (MAGs). In this paper, we review some recent statistical methods for strain identifications based on frequency counts at a set of single nucleotide variants (SNVs) within a set of single-copy marker genes. These methods differ in terms of whether reference genome sequences are needed, how SNVs are called, what methods of deconvolution are used and whether the methods can be applied to multiple samples. We conclude our review with areas that require further research.

Experimental study on failure mechanism of recycled coarse aggregate concrete under uniaxial compression

This paper investigated the micro-crack initiation, development, and interconnection process of recycled coarse aggregate concrete under uniaxial compressive loading from the mesoscale and macroscale. Furthermore, the strain change law of concrete cube in the failure process is recorded by Digital Image Correlation technology. The width and porosity of the interface transition zones were characterized by microhardness tests and backscattered electron imaging. The experimental results show that the compressive strength was increased by 15.77% and 29.68% by aggregate strengthening (RCA is immersed in nano-SiO2 solution) and mortar strengthening (silica fume was added during cement mixing), respectively, compared to untreated specimens. The microhardness of new mortar is increased, and the porosity of ITZOA-NM and ITZOM-NM is reduced by mortar strengthening. The probability of passing penetrating cracks decreases for strengthening interfaces. In the direction perpendicular to the compressive stress, the average strain values of the specimens are inversely proportional to their compressive strength. In the direction parallel to the compressive stress, the average strain fluctuation amplitude of the specimens is inversely proportional to their compressive strength. The strain variation of the specimens with mortar strengthening is the most moderate, and the strain fluctuation amplitude of the untreated specimens shows the most significant fluctuation. In addition, the probability of penetrating cracks passing strengthening interfaces was decreased. This work proposes an in-situ strain analysis method based on DIC technology that considers the inhomogeneity of concrete materials. The strengthening treatment will improve the micro and macro performance of recycled concrete, and correspond to the different performance of samples with different treatment methods in the macro failure process, establishing the relationship between the micro parameters and the macro performance. This provides a new way to study the failure process of recycled concrete from the micro and micro perspectives.

StrainPanDA: Linked reconstruction of strain composition and gene content profiles via pangenome-based decomposition of metagenomic data.

Microbial strains of variable functional capacities coexist in microbiomes. Current bioinformatics methods of strain analysis cannot provide the direct linkage between strain composition and their gene contents from metagenomic data. Here we present Strain-level Pangenome Decomposition Analysis (StrainPanDA), a novel method that uses the pangenome coverage profile of multiple metagenomic samples to simultaneously reconstruct the composition and gene content variation of coexisting strains in microbial communities. We systematically validate the accuracy and robustness of StrainPanDA using synthetic data sets. To demonstrate the power of gene-centric strain profiling, we then apply StrainPanDA to analyze the gut microbiome samples of infants, as well as patients treated with fecal microbiota transplantation. We show that the linked reconstruction of strain composition and gene content profiles is critical for understanding the relationship between microbial adaptation and strain-specific functions (e.g., nutrient utilization and pathogenicity). Finally, StrainPanDA has minimal requirements for computing resources and can be scaled to process multiple species in a community in parallel. In short, StrainPanDA can be applied to metagenomic data sets to detect the association between molecular functions and microbial/host phenotypes to formulate testable hypotheses and gain novel biological insights at the strain or subspecies level.

Deformation of the colliding Luzon volcanic arc: Strain analysis using magnetic fabrics of syn-orogenic mudstones in the Coastal Range, eastern Taiwan

Exposed in the Coastal Range of eastern Taiwan is a portion of the Luzon volcanic arc that has collided with the South China continent since 6 Ma, as well as syn-orogenic sedimentary rocks deposited on the arc and subsequently intensely folded and thrusted. This study sampled syn-orogenic mudstones for the measurement of anisotropy of magnetic susceptibility (AMS) at four sites on the sides of the range. The AMS fabrics reveal a contribution from burial compaction and, less significantly, tectonic shortening which varies slightly across the range. This lateral variation is considered as, for simplicity, a result of two-phase deformation because these rocks were involved in an eastward propagating back thrust system on the colliding arc. A new strain analysis method is developed to estimate the overall tectonic strain by unstraining the pseudo-strains with respect to the AMS measurements at each site with the knowledge about the distribution of the susceptibility ellipsoids in the unstrained state. Strain results reveal that shortening phases occurred before and after the folding, with a shortening ratio of 0.177–0.195 and 0.181–0.248, respectively. The post-folding shortening on the western side is sub-parallel to the range, and the pre-folding shortening on both sides is layer-parallel and nearly perpendicular to the range. Therefore, the mudstones underwent layer-parallel shortening, fold-related tilting and eventually orogen-parallel shortening after deposition. This sheds light on the complexity in deformation of the colliding Luzon arc.

DeepStrain Evidence of Asymptomatic Left Ventricular Diastolic and Systolic Dysfunction in Young Adults With Cardiac Risk Factors.

PurposeTo evaluate if a fully-automatic deep learning method for myocardial strain analysis based on magnetic resonance imaging (MRI) cine images can detect asymptomatic dysfunction in young adults with cardiac risk factors.MethodsAn automated workflow termed DeepStrain was implemented using two U-Net models for segmentation and motion tracking. DeepStrain was trained and tested using short-axis cine-MRI images from healthy subjects and patients with cardiac disease. Subsequently, subjects aged 18–45 years were prospectively recruited and classified among age- and gender-matched groups: risk factor group (RFG) 1 including overweight without hypertension or type 2 diabetes; RFG2 including hypertension without type 2 diabetes, regardless of overweight; RFG3 including type 2 diabetes, regardless of overweight or hypertension. Subjects underwent cardiac short-axis cine-MRI image acquisition. Differences in DeepStrain-based left ventricular global circumferential and radial strain and strain rate among groups were evaluated.ResultsThe cohort consisted of 119 participants: 30 controls, 39 in RFG1, 30 in RFG2, and 20 in RFG3. Despite comparable (>0.05) left-ventricular mass, volumes, and ejection fraction, all groups (RFG1, RFG2, RFG3) showed signs of asymptomatic left ventricular diastolic and systolic dysfunction, evidenced by lower circumferential early-diastolic strain rate (<0.05, <0.001, <0.01), and lower septal circumferential end-systolic strain (<0.001, <0.05, <0.001) compared with controls. Multivariate linear regression showed that body surface area correlated negatively with all strain measures (<0.01), and mean arterial pressure correlated negatively with early-diastolic strain rate (<0.01).ConclusionDeepStrain fully-automatically provided evidence of asymptomatic left ventricular diastolic and systolic dysfunction in asymptomatic young adults with overweight, hypertension, and type 2 diabetes risk factors.

A method for direct estimation of left ventricular global longitudinal strain rate from echocardiograms

We present a new method for measuring global longitudinal strain and global longitudinal strain rate from 2D echocardiograms using a logarithmic-transform correlation (LTC) method. Traditional echocardiography strain analysis depends on user inputs and chamber segmentation, which yield increased measurement variability. In contrast, our approach is automated and does not require cardiac chamber segmentation and regularization, thus eliminating these issues. The algorithm was benchmarked against two conventional strain analysis methods using synthetic left ventricle ultrasound images. Measurement error was assessed as a function of contrast-to-noise ratio (CNR) using mean absolute error and root-mean-square error. LTC showed better agreement to the ground truth strain {({varvec{R}}}^{2}=0.91) and ground truth strain rate {({varvec{R}}}^{2}=0.85) compared with agreement to ground truth for two block-matching speckle tracking algorithms (one based on sum of square difference and the other on Fourier transform correlation; strain {({varvec{R}}}^{2}=0.70), strain rate {({varvec{R}}}^{2}=0.70)). A 200% increase in strain measurement accuracy was observed compared to the conventional algorithms. Subsequently, we tested the method using a 53-subject clinical cohort (20 subjects diseased with cardiomyopathy, 33 healthy controls). Our method distinguished between normal and abnormal left ventricular function with an AUC = 0.89, a 5% improvement over the conventional GLS algorithms.