Danial Jahed Armaghani^1,*, Zida Liu², Hadi Khabbaz¹, Hadi Fattahi³, Diyuan Li², Mohammad Afrazi⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.3, pp. 2421-2451, 2024, DOI:10.32604/cmes.2024.052210 - 31 October 2024

Abstract Tunnel Boring Machines (TBMs) are vital for tunnel and underground construction due to their high safety and efficiency. Accurately predicting TBM operational parameters based on the surrounding environment is crucial for planning schedules and managing costs. This study investigates the effectiveness of tree-based machine learning models, including Random Forest, Extremely Randomized Trees, Adaptive Boosting Machine, Gradient Boosting Machine, Extreme Gradient Boosting Machine (XGBoost), Light Gradient Boosting Machine, and CatBoost, in predicting the Penetration Rate (PR) of TBMs by considering rock mass and material characteristics. These techniques are able to provide a good relationship between input(s)… More >

Rajan Aravind^1,2, Sundararajan Natarajan¹, Krishnankutty Jayakumar², Ratna Kumar Annabattula^1,*

CMES-Computer Modeling in Engineering & Sciences, Vol.141, No.2, pp. 997-1032, 2024, DOI:10.32604/cmes.2024.053047 - 27 September 2024

Abstract Understanding the probabilistic nature of brittle materials due to inherent dispersions in their mechanical properties is important to assess their reliability and safety for sensitive engineering applications. This is all the more important when elements composed of brittle materials are exposed to dynamic environments, resulting in catastrophic fatigue failures. The authors propose the application of a non-intrusive polynomial chaos expansion method for probabilistic studies on brittle materials undergoing fatigue fracture when geometrical parameters and material properties are random independent variables. Understanding the probabilistic nature of fatigue fracture in brittle materials is crucial for ensuring the… More >

Shaochun Ma^1,2,*, Lin Wang¹, Peng Bao^1,*

Journal of Renewable Materials, Vol.10, No.7, pp. 1961-1978, 2022, DOI:10.32604/jrm.2022.018755 - 07 March 2022

Abstract There are a large number of historic buildings which were mainly made of blue-brick masonry in today’s world. However, for the natural and man-made reasons, these historic buildings have been damaged in different degrees. In order to protect historic buildings more scientifically and learn about the preservation state of existing historic buildings, it is necessary to ascertain the material properties of blue brick in historic buildings. The article takes the blue bricks of historical buildings in Kaifeng area of the Central Plains as an example to study. Through the analysis of physical properties, X-ray fluorescence… More > Graphic Abstract

Yanmin Li^1,2, Guifeng Zhao^2,3, Yuhong Ma^1,2,*, Rong Liu^1,2

Journal of Renewable Materials, Vol.10, No.6, pp. 1641-1658, 2022, DOI:10.32604/jrm.2022.018277 - 20 January 2022

Abstract An artificially accelerated alternation of aging and seawater erosion test of rubber materials used in lead rubber bearing (LRB) was performed, mainly to study the time-varying laws of rubber materials mechanical properties. Time-varying laws of the Mooney–Rivlin and Neo-Hookean constitutive parameters of rubber materials under the alternation of aging and seawater erosion were also analyzed. Results indicate that the rubber material mechanical properties were significantly affected by alternation of aging and seawater erosion. Hardness and elongation stress increased exponentially with test time. And 120 days after the test, the hardness increased by 14%, the maximum… More >

Shotaro Taguchi^1,*, Satoru Yoneyama²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.23, No.1, pp. 20-20, 2021, DOI:10.32604/icces.2021.08535

Abstract This study proposes a method for identifying viscoelastic properties that considers time- and temperature dependence of Poisson's ratio using inverse analysis. In this method, displacement distribution, which are input values of inverse analysis, is measured by digital image correlation [1], and unknown material properties are determined using the virtual fields method [2]. This method targets plane stress condition and the Poisson's ratio of the viscoelastic body depends on the time and temperature [3]. This study focuses on the correspondence law and proposes a method for calculating stresses considering time- and temperature dependence of Poisson's ratio. More >

Minliang Liu¹, Liang Liang², Xiaoying Lou³, Glen Iannucci³, Edward Chen³, Bradley Leshnower³, Wei Sun^1,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 53-53, 2019, DOI:10.32604/mcb.2019.07387

Abstract It is well known that mechanical properties of the aortic wall exhibit patient-specific variations. Recent experimental findings also suggest the aortic wall properties are highly region-specific [1-2]. Thus, in vivo heterogeneous (non-uniform) nonlinear mechanical properties of the aortic wall of individual patients needs to be noninvasively identified for accurate prediction of clinical events (e.g. aortic rupture).
In this study, we developed an inverse approach for identification of patient-specific non-uniform material properties of the aortic wall from gated 3D CT scans. This inverse approach leverages the fact that the in vivo transmural mean stress (tension) of… More >

Yue Mei^1,2,3, Stephane Avril^3,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.2, pp. 44-44, 2019, DOI:10.32604/mcb.2019.07034

Abstract Characterizing regional variations of material properties in soft tissues is essential for biomedical engineering and clinical medicine, including but not limited to cancerous disease detection and patient-specific surgical planning of cardiovascular diseases. Identification of nonhomogeneous material property distribution usually requires solving inverse problems in nonlinear elasticity. Generally, inverse algorithms can be categorized into two groups: iterative inversion and direct inversion. In direct inversion, the material property distribution of soft tissues is estimated directly from the equilibrium equations, while the inverse problem is posed as an optimization problem in iterative inversion. In this presentation, we compare… More >

Qingyu Wang¹, Dalin Tang^1,2,*, Gador Canton³, Zheyang Wu², Thomas S. Hatsukami⁴, Kristen L Billiar⁵, Chun Yuan⁶

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 81-82, 2019, DOI:10.32604/mcb.2019.05748

Abstract This article has no abstract. More >

Longling Fan¹, Jing Yao², Chun Yang³, Di Xu², Dalin Tang^1,4,*

Molecular & Cellular Biomechanics, Vol.16, Suppl.1, pp. 41-41, 2019, DOI:10.32604/mcb.2019.05720

Abstract Cardiac pacing has been an effective treatment in the management of patients with arrhythmia. Different pacemaker location may have different impact on pacemaker effectiveness. A novel image-based ventricle animal modeling approach was proposed to integrate echocardiography images, propagating dynamic electric potential on ventricle surface to perform myocardial function assessment. The models will be used to simulate ventricular electrical signal conduction and optimize pacemaker location for better cardiac outcome. One health female adult pig weight 42.5 kg was used to make pacing animal model with different ventricle pacing locations. Pig health status was assessed before undergoing… More >

Longling Fan^1,*, Jing Yao ^{2, *}, Chun Yang³, Di Xu², Dalin Tang^{1, 4, §}

CMES-Computer Modeling in Engineering & Sciences, Vol.114, No.2, pp. 221-237, 2018, DOI:10.3970/cmes.2018.114.221

Abstract Understanding cardiac blood flow behaviors is of importance for cardiovascular research and clinical assessment of ventricle functions. Patient-specific Echo-based left ventricle (LV) fluid-structure interaction (FSI) models were introduced to perform ventricle mechanical analysis, investigate flow behaviors, and evaluate the impact of myocardial infarction (MI) and hypertension on blood flow in the LV. Echo image data were acquired from 3 patients with consent obtained: one healthy volunteer (P1), one hypertension patient (P2), and one patient who had an inferior and posterior myocardial infarction (P3). The nonlinear Mooney-Rivlin model was used for ventricle tissue with material parameter… More >