Article
Engineering, Multidisciplinary
Feifei Zhao, Hong Bao
Summary: The study proposed an improved iFEM based on isogeometric analysis to handle different types of external loads, achieving a unified description of displacement fields, and demonstrated through experiments to be more accurate and effective.
Article
Computer Science, Interdisciplinary Applications
Sebastian Bachmann, Dieter H. Pahr, Alexander Synek
Summary: The objective of this study was to assess the agreement between hFE-based IBR and mu FE-based IBR in predicting hip joint loading. The results showed that using hFE models significantly reduced the computational time and improved the prediction of joint loading history. The study suggests that cortical and trabecular bone should be modeled separately, and at least density-dependent heterogeneous material properties should be used with hFE models to predict joint loading.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2023)
Article
Operations Research & Management Science
Dinh Nho Hao, Le Thi Thu Giang, Nguyen Thi Ngoc Oanh
Summary: This research investigates the problem of determining a term in the right-hand side of elliptic equations from an observation on a part of the boundary. The inverse problem is formulated as an operator equation and stabilized using the Tikhonov regularization method. The regularized problem is discretized based on Hinze's variational discretization concept, and the performance is demonstrated through numerical examples.
Article
Computer Science, Interdisciplinary Applications
Zhirui Fan, Jun Yan, Mathias Wallin, Matti Ristinmaa, Bin Niu, Sean Mooney, Guozhong Zhao
Summary: This study utilizes the advantages of inverse motion analysis to design structures with exact deformed geometry and prescribed load distribution. The optimization is performed by minimizing a general function of the nodal displacement vector and regularizing the design using the partial differential equation filter. The sensitivity analysis is based on the adjoint method. The computational model uses neo-Hookean hyper-elasticity and the finite element method to discretize the balance equations.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2022)
Article
Mathematics, Interdisciplinary Applications
Fynn Bensel, Marlis Reiber, Elise Foulatier, Philipp Junker, Udo Nackenhorst
Summary: Numerical simulation of bone remodelling is a crucial tool for investigating the stability of bone implants and can aid in surgical planning. This paper introduces a numerical approach using gradient enhancement technique to regularize the internal variables in the bone density evolution model. The method's robustness is demonstrated through parametric studies on benchmark examples, and its effectiveness is further validated through a detailed femur model simulation.
COMPUTATIONAL MECHANICS
(2023)
Article
Thermodynamics
Victor Daniel Zegarra Torres, Murilo Augusto Vaz, Julio Cesar Ramalho Cyrino
Summary: In this work, a numerical-experimental methodology is presented for determining the heat flux distribution in oxy-acetylene localized heating processes in the shipbuilding industry. The study shows that the inverse problem methodology can effectively validate the stability of the model and the reliability of the results.
INTERNATIONAL JOURNAL OF THERMAL SCIENCES
(2021)
Article
Ophthalmology
Chanyoung Lee, Guorong Li, W. Daniel Stamer, C. Ross Ethier
Summary: The study aimed to estimate the murine iris biomechanical stiffness by utilizing optical coherence tomography images for living mice and an inverse finite element model. The in vivo murine iris stiffness was found to be 96.1 +/- 54.7 kPa, with gender dependency and evidence of reverse pupillary block. The approach of monitoring iris stiffness in vivo has significant potential for studying potential changes in various pathophysiological conditions of the iris.
EXPERIMENTAL EYE RESEARCH
(2021)
Article
Mathematics, Applied
Zhengfang Zhang, Xiangjing Gao, Xiaoliang Cheng
Summary: This paper investigates the inverse eigenvalue problem for a weighted Helmholtz equation. The density function is estimated based on finite spectral data, and the inverse problem is formulated as a least squared functional with a L(2) regularity term. The continuity of the eigenpairs with respect to the density is proven. Mathematical properties of both continuous and discrete optimization problems are established. A conjugate gradient algorithm is proposed, and numerical results for 1D and 2D inverse eigenvalue problems of the weighted Helmholtz equation are presented to demonstrate the effectiveness and efficiency of the algorithm.
JOURNAL OF SCIENTIFIC COMPUTING
(2023)
Article
Engineering, Biomedical
S. Oliviero, R. Owen, G. C. Reilly, I Bellantuono, E. Dall'Ara
Summary: This study evaluates the ability of different microCT-based bone parameters and microFE models to predict tibial structural mechanical properties in compression. Results show that microFE models can improve the estimation of mouse tibia structural properties and define an optimal failure criterion. The non-invasive method can be longitudinally applied for evaluating temporal changes in bone strength.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2021)
Article
Engineering, Aerospace
Qi Zhang, El Ghali Asri, Zheng H. Zhu
Summary: This paper proposes a robust finite element Kalman filter to estimate the state of flexible space tether systems, which are crucial for space exploration and satellite missions. The proposed estimator combines position/velocity sensors, distributed fiber optic strain measurement, and a finite element-based Kalman filter to overcome the challenges of measuring the system's state. It is mathematically proven to be observable, stable, and robust, as demonstrated through numerical simulations.
Article
Engineering, Multidisciplinary
Runzhou You, Liang Ren
Summary: The enhanced inverse beam element, iEBT2, developed in this paper based on classical beam theory, minimizes a weighted-errors functional to accurately estimate the deformed shape of structures using the inverse finite element method. The improved coefficient matrix KR ensures the existence of solutions in iFEM formulation, making it a practical tool for shape-sensing analysis of civil infrastructures.
Article
Multidisciplinary Sciences
Li Cai, Lei Ren, Yongheng Wang, Wenxian Xie, Guangyu Zhu, Hao Gao
Summary: This study developed three surrogate models based on machine learning methods for fast parameter estimation of left ventricular myocardium. The results showed that the XGBoost model outperformed the other two surrogate models in predicting LV diastolic dynamics and estimating passive parameters. Further studies are needed to explore the use of XGBoost in emulating cardiac pump function in a multi-physics and multi-scale framework.
ROYAL SOCIETY OPEN SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Jairan Nafar Dastgerdi, Fariborz Sheibanian, Heikki Remes, Hossein Hosseini Toudeshky
Summary: This study investigates the effect of peak load on micro-crack formation in high-strength steel, finding that surface roughness has a greater influence on micro-crack formation than residual stress, and the crack size increases exponentially with increasing peak load magnitudes.
Article
Chemistry, Analytical
Daniele Oboe, Dario Poloni, Claudio Sbarufatti, Marco Giglio
Summary: The inverse finite element method (iFEM) is used to compute the displacement and strain field of a structure based on strain measurements and a geometric discretization. Previous works focused on damage detection and localization, but did not estimate the damage size accurately. To address this issue, a new approach is proposed, introducing damage systematically in the iFEM model to minimize discrepancy with the physical structure. The approach was experimentally verified on an aluminum plate subjected to fatigue crack propagation.
Article
Engineering, Multidisciplinary
Run-Zhou You, Ting-Hua Yi, Liang Ren, Hong-Nan Li
Summary: A method for quasi-distributed deflection estimation using onboard strain data is proposed in this paper. An equivalent analysis model is established by installing a self-designed sensing bar on the bridge girder. The model is discretized using an innovative inverse finite element method and a strain-deflection transformation matrix is established. Quasi-distributed bridge deflections are estimated by reconstructing the deformed shape of the equivalent analysis model. The method is simple, general, computationally fast, and has been validated experimentally.
Article
Anatomy & Morphology
Kim Deckers, Zewdi J. Tsegai, Matthew M. Skinner, Angel Zeininger, Tracy L. Kivell
Summary: The morphology of trabecular bone in adult primates reflects mechanical loading related to locomotion. However, ontogenetic studies suggest that there may be an adaptive lag between trabecular bone response and current mechanical loading patterns, resulting in adult trabecular bone morphology reflecting juvenile behaviors.
JOURNAL OF ANATOMY
(2022)
Article
Engineering, Biomedical
Sebastian Bachmann, Dieter H. Pahr, Alexander Synek
Summary: Inverse bone remodeling can infer physiological loading conditions from bone microstructure. Homogenized finite element models can be used as an alternative to micro-structured models to improve computational efficiency. A new continuum-level target stimulus is proposed and applied to predict physiological loading in different models.
ANNALS OF BIOMEDICAL ENGINEERING
(2023)
Article
Orthopedics
Arastoo Nia, Natasa Jeremic, Domenik Popp, Lukas Schmoelz, Janina Patsch, Kevin Doering, Michael Weber, Alexander Synek, Dieter H. Pahr, Silke Aldrian
Summary: Recently, a study evaluated the feasibility of radiography-based bone mineral density (BMD) measurement using a graded aluminum phantom. Strong correlations were found between aluminum phantom radiography-based mean gray value (mGV) and DXA-derived BMD for the ultradistal radius, and a moderate correlation was found for the femoral neck. Aluminum phantom radiography could be a cost-efficient and low-radiation dose method for screening and diagnosing osteoporosis, especially in areas with limited DXA availability. Further investigation and assessment of specificity and sensitivity is needed.
JOURNAL OF ORTHOPAEDIC RESEARCH
(2023)
Article
Multidisciplinary Sciences
Simon A. Chapple, Matthew M. Skinner
Summary: Studies have shown that the current nomenclature system for primate molar teeth is inadequate in accurately identifying and distinguishing the various structures of the crown surface. Investigations of mandibular crown morphology at the enamel-dentine junction have revealed new patterns of lower molar accessory cusp expression, which differ from the expected patterns based on existing literature. In light of this, a conservative naming scheme based on simple location-based categorizations is proposed until a better understanding of the developmental and phylogenetic origin of these structures is achieved.
Article
Computer Science, Interdisciplinary Applications
Sebastian Bachmann, Dieter H. Pahr, Alexander Synek
Summary: The objective of this study was to assess the agreement between hFE-based IBR and mu FE-based IBR in predicting hip joint loading. The results showed that using hFE models significantly reduced the computational time and improved the prediction of joint loading history. The study suggests that cortical and trabecular bone should be modeled separately, and at least density-dependent heterogeneous material properties should be used with hFE models to predict joint loading.
COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE
(2023)
Article
Engineering, Biomedical
Morteza Amini, Andreas Reisinger, Alexander Synek, Lena Hirtler, Dieter Pahr
Summary: Despite improvements in QCT-FE models for estimating femoral strength, there is a lack of clinical adoption. This study validated a QCT-FE model and assessed the influence of experimental and modeling parameters on its predictive ability. The model showed good correlation with experimental results in the neutral stance position and was sensitive to loading angles and embedding geometry.
JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS
(2023)
Article
Anatomy & Morphology
Samar M. Syeda, Zewdi J. Tsegai, Marine Cazenave, Matthew M. Skinner, Tracy L. Kivell
Summary: Primate fingers are in contact with the environment during locomotion and manipulation, and cortical bone structure reflects differences in hand use among different taxa. The results of this study provide insights into hand use in fossil hominins.
JOURNAL OF ANATOMY
(2023)
Article
Anthropology
Ameline Bardo, Christopher J. J. Dunmore, Raphael Cornette, Tracy L. L. Kivell
Summary: By examining the shape covariation between the entire trapezium and Mc1 in extant hominids, we can understand the differences in thumb use. Our findings show significant shape covariation in the trapezium-Mc1 joint of Homo sapiens and Gorilla gorilla gorilla, indicating different intercarpal and carpometacarpal joint postures. These results provide insights into thumb use in fossil hominins.
AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY
(2023)
Article
Anthropology
Samuel B. Tanner, Ameline Bardo, Thomas W. Davies, Christopher J. Dunmore, Richard E. Johnston, Nicholas J. Owen, Tracy L. Kivell, Matthew M. Skinner
Summary: This study analyzed the variations in overall bone shape and cross-sectional geometric shape of metacarpals 1-5, and tested the correlation between these two aspects of bone structure. The differences in cortical structure and external shape of metacarpals between different human groups suggest variations in the type and frequency of manual activities.
AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY
(2023)
Article
Anthropology
Emma E. Bird, Tracy L. Kivell, Christopher J. Dunmore, Matthew W. Tocheri, Matthew M. Skinner
Summary: This study examines the distribution of trabecular bone in the proximal capitates of different hominid species, both extant and extinct, and finds that modern humans and Neandertals share a unique distribution pattern that suggests they regularly loaded their midcarpal joints along the full extent of the dart-thrower's motion. Fossil hominins show different patterns, indicating different loading mechanisms for their midcarpal joints compared to modern humans and Neandertals.
AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY
(2023)
Article
Anthropology
Christopher J. Dunmore, Sebastian Bachmann, Alexander Synek, Dieter H. Pahr, Matthew M. Skinner, Tracy L. Kivell
Summary: Recent studies have found differences in the bone structure of the first metacarpal among modern humans and other primates, which are associated with thumb usage. These findings are important for inferring the thumb use of fossil hominins.
AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY
(2023)
Article
Anthropology
Emma E. Bird, Tracy L. Kivell, Matthew M. Skinner
Summary: This study investigates the relative differences in internal bone architecture among a broad sample of great apes and humans, and finds that these differences can be used to differentiate locomotor modes in hominoids. The importance of the triquetrum and lunate bones in this differentiation warrants further research, and establishing patterns across more carpal joints can provide critical context for interpreting fossil species.
AMERICAN JOURNAL OF BIOLOGICAL ANTHROPOLOGY
(2022)