CMES-Computer Modeling in Engineering & Sciences

About the Journal

This journal publishes original research papers of reasonable permanent value, in the areas of computational mechanics, computational physics, computational chemistry, and computational biology, pertinent to solids, fluids, gases, biomaterials, and other continua. Various length scales (quantum, nano, micro, meso, and macro), and various time scales (picoseconds to hours) are of interest. Papers which deal with multi-physics problems, as well as those which deal with the interfaces of mechanics, chemistry, and biology, are particularly encouraged. New computational approaches, and more efficient algorithms, which eventually make near-real-time computations possible, are welcome. Original papers dealing with new methods such as meshless methods, and mesh-reduction methods are sought.

Indexing and Abstracting

Science Citation Index (Web of Science): 2018 Impact Factor 0.796; Current Contents: Engineering, Computing & Technology; Scopus Citescore (Impact per Publication 2018): 1.02; SNIP (Source Normalized Impact per Paper 2018): 0.498; RG Journal Impact (average over last three years); Engineering Index (Compendex); Applied Mechanics Reviews; Cambridge Scientific Abstracts: Aerospace and High Technology, Materials Sciences & Engineering, and Computer & Information Systems Abstracts Database; CompuMath Citation Index; INSPEC Databases; Mathematical Reviews; MathSci Net; Mechanics; Science Alert; Science Navigator; Zentralblatt fur Mathematik; Portico, etc...

  • Addition Formulas of Leaf Functions and Hyperbolic Leaf Functions
  • Abstract Addition formulas exist in trigonometric functions. Double-angle and half-angle formulas can be derived from these formulas. Moreover, the relation equation between the trigonometric function and the hyperbolic function can be derived using an imaginary number. The inverse hyperbolic function is similar to the inverse trigonometric function , such as the second degree of a polynomial and the constant term 1, except for the sign − and +. Such an analogy holds not only when the degree of the polynomial is 2, but also for higher degrees. As such, a function exists with respect… More
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  • Determination of Time-Dependent Coefficients for a Weakly Degenerate Heat Equation
  • Abstract In this paper, we consider solving numerically for the first time inverse problems of determining the time-dependent thermal diffusivity coefficient for a weakly degenerate heat equation, which vanishes at the initial moment of time, and/or the convection coefficient along with the temperature for a one-dimensional parabolic equation, from some additional information about the process (the so-called over-determination conditions). Although uniquely solvable these inverse problems are still ill-posed since small changes in the input data can result in enormous changes in the output solution. The finite difference method with the Crank-Nicolson scheme combined with the nonlinear Tikhonov regularization are employed. The… More
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  • A Staggered Grid Method for Solving Incompressible Flow on Unstructured Meshes
  • Abstract A finite volume method based unstructured grid is presented to solve the two dimensional viscous and incompressible flow. The method is based on the pressure-correction concept and solved by using a semi-staggered grid technique. The computational procedure can handle cells of arbitrary shapes, although solutions presented in this paper were only involved with triangular and quadrilateral cells. The pressure or pressure-correction value was stored on the vertex of cells. The mass conservation equation was discretized on the dual cells surrounding the vertex of primary cells, while the velocity components and other scale variables were saved on the central of primary… More
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  • Toward a More Accurate Web Service Selection Using Modified Interval DEA Models with Undesirable Outputs
  • Abstract With the growing number of Web services on the internet, there is a challenge to select the best Web service which can offer more quality-of-service (QoS) values at the lowest price. Another challenge is the uncertainty of QoS values over time due to the unpredictable nature of the internet. In this paper, we modify the interval data envelopment analysis (DEA) models [Wang, Greatbanks and Yang (2005)] for QoS-aware Web service selection considering the uncertainty of QoS attributes in the presence of desirable and undesirable factors. We conduct a set of experiments using a synthesized dataset to show the capabilities of… More
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  • Numerical Study of the Distribution of Temperatures and Relative Humidity in a Ventilated Room Located in Warm Weather
  • Abstract In the present study, an analysis of the heat and mass transfer in a ventilated cavity in a warm climate zone was carried out to analyze, among others, the temperatures and percentage of relative humidity (RH). The governing equations of the mathematical model were solved through the finite volume method. We used the k-ε turbulence mode to find the results of the variables of interest in seven climate records on a given day. The velocity of the inlet flow of the air-H2O mixture was varied through the Reynolds number (Re) from 500 to 10000. The outdoor weather conditions considered were… More
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  • Terminal Sliding Mode Controllers for Hydraulic Turbine Governing System with Bifurcated Penstocks under Input Saturation
  • Abstract Terminal sliding mode controller method is introduced to enhance the regulation performance of the hydraulic turbine governing system (HTGS). For the purpose of describing the characteristics of controlled system and deducing the control rule, a nonlinear mathematic model of hydraulic turbine governing system with bifurcated penstocks (HTGSBF) under control input saturation is established, and the input/output state linearization feedback approach is used to obtain the relationship between turbine speed and controller output. To address the control input saturation problem, an adaptive assistant system is designed to compensate for controller truncation. Numerical simulations have been conducted under fixed point stabilization and… More
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  • Machine Learning Model Comparison for Automatic Segmentation of Intracoronary Optical Coherence Tomography and Plaque Cap Thickness Quantification
  • Abstract Optical coherence tomography (OCT) is a new intravascular imaging technique with high resolution and could provide accurate morphological infor￾mation for plaques in coronary arteries. However, its segmentation is still com￾monly performed manually by experts which is time-consuming. The aim of this study was to develop automatic techniques to characterize plaque components and quantify plaque cap thickness using 3 machine learning methods including convolutional neural network (CNN) with U-Net architecture, CNN with Fully convolutional DenseNet (FC-DenseNet) architecture and support vector machine (SVM). In vivo OCT and intravascular ultrasound (IVUS) images were acquired from two patients at Emory University with informed consent… More
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  • Building Information Modeling-Based Secondary Development System for 3D Modeling of Underground Pipelines
  • Abstract Underground pipeline networks constitute a major component of urban infrastructure, and thus, it is imperative to have an efficient mechanism to manage them. This study introduces a secondary development system to efficiently model underground pipeline networks, using the building information modeling (BIM)-based software Revit. The system comprises separate pipe point and tubulation models. Using a Revit application programming interface (API), the spatial position and attribute data of the pipe points are extracted from a pipeline database, and the corresponding tubulation data are extracted from a tubulation database. Using the Family class in Revit API, the cluster in the self-built library… More
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  • Identification of the Discrete Element Model Parameters for Rock-Like Brittle Materials
  • Abstract An inverse method for parameters identification of discrete element model combined with experiment is proposed. The inverse problem of parameter identification is transmitted to solve an optimization problem by minimizing the distance between the numerical calculations and experiment responses. In this method, the discrete element method is employed as numerical calculator for the forward problem. Then, the orthogonal experiment design with range analysis was used to carry out parameters sensitivity analysis. In addition, to improve the computational efficiency, the approximate model technique is used to replace the actual computational model. The intergeneration projection genetic algorithm (IP-GA) is employed as the… More
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  • An ADI Finite Volume Element Method for a Viscous Wave Equation with Variable Coefficients
  • Abstract Based on rectangular partition and bilinear interpolation, we construct an alternating-direction implicit (ADI) finite volume element method, which combined the merits of finite volume element method and alternating direction implicit method to solve a viscous wave equation with variable coefficients. This paper presents a general procedure to construct the alternating-direction implicit finite volume element method and gives computational schemes. Optimal error estimate in L2 norm is obtained for the schemes. Compared with the finite volume element method of the same convergence order, our method is more effective in terms of running time with the increasing of the computing scale. Numerical… More
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  • A Discrete Model of TB Dynamics in Khyber Pakhtunkhwa-Pakistan
  • Abstract The present paper investigates the theoretical analysis of the tuberculosis (TB) model in the discrete-time case. The model is parameterized by the TB infection cases in the Pakistani province of Khyber Pakhtunkhwa between 2002 and 2017. The model is parameterized and the basic reproduction number is obtained and it is found R0 ¼ 1:5853. The stability analysis for the model is presented and it is shown that the discrete-time tuberculosis model is stable at the disease-free equilibrium whenever R0 < 1 and further we establish the results for the endemic equilibria and prove that the model is globally asymptotically stable… More
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  • RBF-FD Method for Some Dispersive Wave Equations and Their Eventual Periodicity
  • Abstract In this paper, we approximate the solution and also discuss the periodic behavior termed as eventual periodicity of solutions of (IBVPs) for some dispersive wave equations on a bounded domain corresponding to periodic forcing. The constructed numerical scheme is based on radial kernels and local in nature like finite difference method. The temporal variable is executed through RK4 scheme. Due to the local nature and sparse differentiation matrices our numerical scheme efficiently recovers the solution. The results achieved are validated and examined with other methods accessible in the literature. More
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  • T-Splines for Isogeometric Analysis of Two-Dimensional Nonlinear Problems
  • Abstract Nonlinear behaviors are commonplace in many complex engineering applications, e.g., metal forming, vehicle crash test and so on. This paper focuses on the T-spline based isogeometric analysis of two-dimensional nonlinear problems including general large deformation hyperelastic problems and small deformation elastoplastic problems, to reveal the advantages of local refinement property of T-splines in describing nonlinear behavior of materials. By applying the adaptive refinement capability of T-splines during the iteration process of analysis, the numerical simulation accuracy of the nonlinear model could be increased dramatically. The Bézier extraction of the T-splines provides an element structure for isogeometric analysis that can be… More
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  • Extracting Sub-Networks from Brain Functional Network Using Graph Regularized Nonnegative Matrix Factorization
  • Abstract Currently, functional connectomes constructed from neuroimaging data have emerged as a powerful tool in identifying brain disorders. If one brain disease just manifests as some cognitive dysfunction, it means that the disease may affect some local connectivity in the brain functional network. That is, there are functional abnormalities in the sub-network. Therefore, it is crucial to accurately identify them in pathological diagnosis. To solve these problems, we proposed a sub-network extraction method based on graph regularization nonnegative matrix factorization (GNMF). The dynamic functional networks of normal subjects and early mild cognitive impairment (eMCI) subjects were vectorized and the functional connection… More
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  • Thermal Modeling and Analysis of Metal Foam Heat Sink with Thermal Equilibrium and Non-Equilibrium Models
  • Abstract In the present study, the thermal performance of metal foam heat sink was numerically investigated by adopting the local thermal non-equilibrium (LTNE) model and local thermal equilibrium (LTE) model. Temperature field distributions and temperature difference field distributions of solid and fluid phases were presented. Detailed thermal performance comparisons based on the LTE and LTNE models were evaluated by considering the effects of the relevant metal foam morphological and channel geometrical parameters. Results indicate that a distinct temperature difference exists between the solid and fluid phases when the LTNE effect is pronounced. The average Nusselt numbers predicted by both the LTE… More
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