We report theoretically on the sound transmission loss performance through a periodic double plat... more We report theoretically on the sound transmission loss performance through a periodic double plate acoustic metamaterial made of lateral local resonance (LLR) substructure. The unit cell of the substructure consists of a four link mechanism, two lateral resonators, and a vertical spring. The combination of space harmonic expansion and Bloch-Floquet theorem are used to analyze this present study. Computed results show that high sound transmission loss (STL) up to 60 dB at 62 Hz is reached with the metamaterial plate while the mass spring mass resonant is observed for the conventional periodic double plate at the same frequency. The introduction of a negative stiffness spring causes an increased STL at low frequency. The potential of lateral resonant metamaterials to improve the sound transmission loss (STL) in the frequency region around the mass-spring-mass resonance for periodic double panel partitions is demonstrated.
Journal of Biomimetics, Biomaterials and Biomedical Engineering, Feb 1, 2020
The knee at times undergoes a surgical process to substitute the weight-bearing surfaces of the k... more The knee at times undergoes a surgical process to substitute the weight-bearing surfaces of the knee joint. This procedure relieves the pain and disability around the knee joint. This research paper studied the knee arthroplasty, also referred to as knee replacement. This work was aided with computer vision for visual and accuracy. Autodesk fusion 360 and the stl files were used to generate cemented, posterior stabilised knee prosthesis and imported into the COMSOL Multiphysics software. Then, the three-dimensional models of the total knee arthroplasty (TKA) prosthetic structure are produced. The prosthetic components are modelled as linear isotropic elastic materials. Finite element (FE) simulations using COMSOL Multiphysics on a CAD model of a knee are effectuated to show the effect of several loads and strains on the knee. FE analysis of the model indicates that the orthotropic model depicts a more realistic stress distribution of the knee as it reveals the detailed anatomy of the entire knee structure. The computational results of this work displayed a fair agreement with experimental information from the literature.
The geometric nonlinearity resulting from large deformation of compliant members has continued to... more The geometric nonlinearity resulting from large deformation of compliant members has continued to be an interesting research topic in nonlinear mechanics. In this study, two standard variational iteration algorithms, VIM-I and VIM-III are employed to investigate the large deformation of the continuum compliant beam under point load. The VIM is an efficient technique that bypasses the linearization process and proffers solutions to nonlinear problems. The horizontal and vertical displacements of the continuum compliant cantilever beam free end are expressed in explicit analytical forms. Numerical experiment and simulations were carried out to validate the efficacy and applicability of the semi-analytical method. The VIM-I was split into two; VIM-I(A) and VIM-I(B), with the difference being the initial approximations. The results from the VIM-I(A), VIM-I(B) and VIM-III algorithms were compared with the experimental and exact solution. The outcomes reveal that both algorithms correlated well with the analytical solution and experimental result.
Several factors may contribute directly or indirectly to the structural failure of metallic pipes... more Several factors may contribute directly or indirectly to the structural failure of metallic pipes. The most important of which is corrosion. Corrosivity of pipes is not a directly measurable parameter as pipe corrosion is a very random phenomenon. The main aim of the present study is to develop a neuro-fuzzy model capable of establishing corrosion rate criterion as a function of pipe burial depth, soil types, and properties for the prediction of deterioration of metallic pipe conveying fluid. The proposed model includes a fuzzy model and the artificial neural network (ANN) to determine soil corrosivity potential (CoP) based on soil properties. The combination contains the data of linguistic variables characterising various soil properties, and learning capability of the system that constructs relationships among those soil properties and CoP. Subsequently, the artificial neuro-fuzzy inference system (ANFIS) maps each element of its input membership function to an output membership f...
Journal of Biomimetics, Biomaterials and Biomedical Engineering, Nov 1, 2019
Normal oral food ingestion processes such as mastication would not have been possible without the... more Normal oral food ingestion processes such as mastication would not have been possible without the teeth. The human teeth are subjected to many cyclic loadings per day. This, in turn, exerts forces on the teeth just like an engineering material undergoing the same cyclic loading. Over a period, there will be the creation of microcracks on the teeth that might not be visible ab initio. The constant formation of these microcracks weakens the teeth structure and foundation that result in its fracture. Therefore, the need to predict the fatigue life for human teeth is essential. In this paper, a continuum damage mechanics (CDM) based model is employed to evaluate the fatigue life of the human teeth. The material characteristic of the teeth is captured within the framework of the elastoplastic model. By applying the damage evolution equivalence, a mathematical formula is developed that describes the fatigue life in terms of the stress amplitude. Existing experimental data served as a guide as to the completeness of the proposed model. Results as a function of age and tubule orientation are presented. The outcomes produced by the current study have substantial agreement with the experimental results when plotted on the same axes. There is a notable difference in the number of cycles to failure as the tubule orientation increases. It is also revealed that the developed model could forecast for any tubule orientation and be adopted for both young and old teeth.
Biomaterials and biomechanics in bioengineering, Sep 1, 2020
In this study, the mathematical model that describes blood cell development in the bone marrow (i... more In this study, the mathematical model that describes blood cell development in the bone marrow (i.e., hematopoiesis) has been studied via the Homotopy Perturbation Method (HPM). The results from the present work compared very well with the numerical solutions from published literature. This work has shown that the HPM is viable for solving delay differential equations born from hematopoiesis problem. The influence of the proliferating cells loss rate, time delay rate and the phase re-entry rate on the population densities of both the proliferating and resting cells were also determined through the underlined procedure.
Continuum topology of continuous, monolithic compliant mechanisms is designed for finite elastic ... more Continuum topology of continuous, monolithic compliant mechanisms is designed for finite elastic deformation such that an output port moves in a desired direction when a specified force is applied through an input port. The pseudo-rigid body equivalent of compliant mechanisms (CMs) has been the conventional approach used by earlier researchers to synthesize and analyze compliant mechanisms. Attempts at direct analysis from existing literature are predicted on such assumptions as static linearity or a few times geometric nonlinear conditions. These are justifiable in several situations where compliant systems have been successful in replacing materials with several moving parts. However, the application domain of compliant mechanisms is widening to dynamic environment where the deformations are relatively large. It is therefore necessary to consider nonlinearities resulting from geometry and hyperelasticity. In this paper, methods of continuum mechanics and nonlinear finite element method were deployed to develop model that could capture the behaviour of compliant mechanisms. A hybrid system of symbolic algebra (AceGEN) and a compiled back end (AceFEM) were employed, leveraging both ease of use and computational efficiency. Numerical results using published laboratory investigated compliant mechanisms reveal the deviation that exists with linear and only geometric nonlinear assumptions.
Journal of Biomimetics, Biomaterials and Biomedical Engineering, 2021
The deformation of the human breast, especially that of the female, under variable pressure condi... more The deformation of the human breast, especially that of the female, under variable pressure conditions, has been a recent focus for researchers, both in the computational biomechanics, computational biology and the health sector. When the deformation of the breast is large, it hampers suitable cyst tracing as a mammographic biopsy precontrive data. Finite element methods (FEM) has been instrumental in the currently studied practices to trail nodules dislocation. However, the effect of breast material constitution, especially that of a fibrocystic composition, on the biomechanical response of these nodules has gained less attention. The present study is aimed at developing a finite element fibrocystic breast model within the frame of biosolid mechanics and material hyperelasticity to model the breast deformation at finite strain. The geometry of a healthy stress‐free breast is modelled from a magnetic resonance image (MRI) using tissues deformations measurements and solid modelling t...
We report theoretically on the sound transmission loss performance through a periodic double plat... more We report theoretically on the sound transmission loss performance through a periodic double plate acoustic metamaterial made of lateral local resonance (LLR) substructure. The unit cell of the substructure consists of a four link mechanism, two lateral resonators, and a vertical spring. The combination of space harmonic expansion and Bloch-Floquet theorem are used to analyze this present study. Computed results show that high sound transmission loss (STL) up to 60 dB at 62 Hz is reached with the metamaterial plate while the mass spring mass resonant is observed for the conventional periodic double plate at the same frequency. The introduction of a negative stiffness spring causes an increased STL at low frequency. The potential of lateral resonant metamaterials to improve the sound transmission loss (STL) in the frequency region around the mass-spring-mass resonance for periodic double panel partitions is demonstrated.
Journal of Biomimetics, Biomaterials and Biomedical Engineering, Feb 1, 2020
The knee at times undergoes a surgical process to substitute the weight-bearing surfaces of the k... more The knee at times undergoes a surgical process to substitute the weight-bearing surfaces of the knee joint. This procedure relieves the pain and disability around the knee joint. This research paper studied the knee arthroplasty, also referred to as knee replacement. This work was aided with computer vision for visual and accuracy. Autodesk fusion 360 and the stl files were used to generate cemented, posterior stabilised knee prosthesis and imported into the COMSOL Multiphysics software. Then, the three-dimensional models of the total knee arthroplasty (TKA) prosthetic structure are produced. The prosthetic components are modelled as linear isotropic elastic materials. Finite element (FE) simulations using COMSOL Multiphysics on a CAD model of a knee are effectuated to show the effect of several loads and strains on the knee. FE analysis of the model indicates that the orthotropic model depicts a more realistic stress distribution of the knee as it reveals the detailed anatomy of the entire knee structure. The computational results of this work displayed a fair agreement with experimental information from the literature.
The geometric nonlinearity resulting from large deformation of compliant members has continued to... more The geometric nonlinearity resulting from large deformation of compliant members has continued to be an interesting research topic in nonlinear mechanics. In this study, two standard variational iteration algorithms, VIM-I and VIM-III are employed to investigate the large deformation of the continuum compliant beam under point load. The VIM is an efficient technique that bypasses the linearization process and proffers solutions to nonlinear problems. The horizontal and vertical displacements of the continuum compliant cantilever beam free end are expressed in explicit analytical forms. Numerical experiment and simulations were carried out to validate the efficacy and applicability of the semi-analytical method. The VIM-I was split into two; VIM-I(A) and VIM-I(B), with the difference being the initial approximations. The results from the VIM-I(A), VIM-I(B) and VIM-III algorithms were compared with the experimental and exact solution. The outcomes reveal that both algorithms correlated well with the analytical solution and experimental result.
Several factors may contribute directly or indirectly to the structural failure of metallic pipes... more Several factors may contribute directly or indirectly to the structural failure of metallic pipes. The most important of which is corrosion. Corrosivity of pipes is not a directly measurable parameter as pipe corrosion is a very random phenomenon. The main aim of the present study is to develop a neuro-fuzzy model capable of establishing corrosion rate criterion as a function of pipe burial depth, soil types, and properties for the prediction of deterioration of metallic pipe conveying fluid. The proposed model includes a fuzzy model and the artificial neural network (ANN) to determine soil corrosivity potential (CoP) based on soil properties. The combination contains the data of linguistic variables characterising various soil properties, and learning capability of the system that constructs relationships among those soil properties and CoP. Subsequently, the artificial neuro-fuzzy inference system (ANFIS) maps each element of its input membership function to an output membership f...
Journal of Biomimetics, Biomaterials and Biomedical Engineering, Nov 1, 2019
Normal oral food ingestion processes such as mastication would not have been possible without the... more Normal oral food ingestion processes such as mastication would not have been possible without the teeth. The human teeth are subjected to many cyclic loadings per day. This, in turn, exerts forces on the teeth just like an engineering material undergoing the same cyclic loading. Over a period, there will be the creation of microcracks on the teeth that might not be visible ab initio. The constant formation of these microcracks weakens the teeth structure and foundation that result in its fracture. Therefore, the need to predict the fatigue life for human teeth is essential. In this paper, a continuum damage mechanics (CDM) based model is employed to evaluate the fatigue life of the human teeth. The material characteristic of the teeth is captured within the framework of the elastoplastic model. By applying the damage evolution equivalence, a mathematical formula is developed that describes the fatigue life in terms of the stress amplitude. Existing experimental data served as a guide as to the completeness of the proposed model. Results as a function of age and tubule orientation are presented. The outcomes produced by the current study have substantial agreement with the experimental results when plotted on the same axes. There is a notable difference in the number of cycles to failure as the tubule orientation increases. It is also revealed that the developed model could forecast for any tubule orientation and be adopted for both young and old teeth.
Biomaterials and biomechanics in bioengineering, Sep 1, 2020
In this study, the mathematical model that describes blood cell development in the bone marrow (i... more In this study, the mathematical model that describes blood cell development in the bone marrow (i.e., hematopoiesis) has been studied via the Homotopy Perturbation Method (HPM). The results from the present work compared very well with the numerical solutions from published literature. This work has shown that the HPM is viable for solving delay differential equations born from hematopoiesis problem. The influence of the proliferating cells loss rate, time delay rate and the phase re-entry rate on the population densities of both the proliferating and resting cells were also determined through the underlined procedure.
Continuum topology of continuous, monolithic compliant mechanisms is designed for finite elastic ... more Continuum topology of continuous, monolithic compliant mechanisms is designed for finite elastic deformation such that an output port moves in a desired direction when a specified force is applied through an input port. The pseudo-rigid body equivalent of compliant mechanisms (CMs) has been the conventional approach used by earlier researchers to synthesize and analyze compliant mechanisms. Attempts at direct analysis from existing literature are predicted on such assumptions as static linearity or a few times geometric nonlinear conditions. These are justifiable in several situations where compliant systems have been successful in replacing materials with several moving parts. However, the application domain of compliant mechanisms is widening to dynamic environment where the deformations are relatively large. It is therefore necessary to consider nonlinearities resulting from geometry and hyperelasticity. In this paper, methods of continuum mechanics and nonlinear finite element method were deployed to develop model that could capture the behaviour of compliant mechanisms. A hybrid system of symbolic algebra (AceGEN) and a compiled back end (AceFEM) were employed, leveraging both ease of use and computational efficiency. Numerical results using published laboratory investigated compliant mechanisms reveal the deviation that exists with linear and only geometric nonlinear assumptions.
Journal of Biomimetics, Biomaterials and Biomedical Engineering, 2021
The deformation of the human breast, especially that of the female, under variable pressure condi... more The deformation of the human breast, especially that of the female, under variable pressure conditions, has been a recent focus for researchers, both in the computational biomechanics, computational biology and the health sector. When the deformation of the breast is large, it hampers suitable cyst tracing as a mammographic biopsy precontrive data. Finite element methods (FEM) has been instrumental in the currently studied practices to trail nodules dislocation. However, the effect of breast material constitution, especially that of a fibrocystic composition, on the biomechanical response of these nodules has gained less attention. The present study is aimed at developing a finite element fibrocystic breast model within the frame of biosolid mechanics and material hyperelasticity to model the breast deformation at finite strain. The geometry of a healthy stress‐free breast is modelled from a magnetic resonance image (MRI) using tissues deformations measurements and solid modelling t...
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