Open Access
EDITORIAL
Jingfa Li1, Liang Gong2, Yongtu Liang3, Zhiguo Qu4, Bo Yu1,*
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 1-4, 2020, DOI:10.32604/cmes.2020.011924
(This article belongs to this Special Issue: Advances in Modeling and Simulation of Complex Heat Transfer and Fluid Flow)
Abstract This article has no abstract. More >
Open Access
ARTICLE
Heng Zhang1, Tingyu Li2, Dongxu Han1, *, Daobing Wang1, Dongliang Sun1, Bo Yu1
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 5-21, 2020, DOI:10.32604/cmes.2020.09290
(This article belongs to this Special Issue: Advances in Modeling and Simulation of Complex Heat Transfer and Fluid Flow)
Abstract Simulation of fluid flow in the fractured porous media is very important and
challenging. Researchers have developed some models for fractured porous media. With
the development of related research in recent years, the prospect of embedded discrete fracture model (EDFM) is more and more bright. However, since the size of the fractures in the
actual reservoir varies greatly, a very fine grid should be used which leads to a huge burden
to the computing resources. To address this challenge, in the present paper, an upscaling
based model is proposed. In this model, the flow in large-scale fractures is directly
described… More >
Open Access
ARTICLE
Lingtong Li1, Zaiguo Fu1, *, Benxiang Li2, Qunzhi Zhu1
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 23-44, 2020, DOI:10.32604/cmes.2020.09299
(This article belongs to this Special Issue: Advances in Modeling and Simulation of Complex Heat Transfer and Fluid Flow)
Abstract The earth to fluid pipe (ETFP) system has been widely applied to various energy
engineering. The numerical model of the heat transfer process in the ETFP system with a
shallow-buried horizontal or a deep-buried vertical U-shape pipe adopted in practical
engineering was established and the model distinctions were pointed out. The comparison
of the thermal performance between the two types of ETFP system under various schemes
was conducted on the basis of numerical prediction. The results showed that the thermal
parameters of the ETFP system with a shallow-buried horizontal pipe were influenced
by the inlet velocity and ground temperature obviously.… More >
Open Access
ARTICLE
Shihao Fan, Mingliang Chang*, Shouxi Wang, Qing Quan, Yong Wang, Dan Li
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 45-59, 2020, DOI:10.32604/cmes.2020.08973
(This article belongs to this Special Issue: Advances in Modeling and Simulation of Complex Heat Transfer and Fluid Flow)
Abstract It is important to determine the insulation thickness in the design of the
buried hot oil pipelines. The economic thickness of the insulation layer not only
meets the needs of the project but also maximizes the investment and environmental benefits. However, as a significant evaluation, the environmental factors
haven’t been considered in the previous study. Considering this factor, the mathematical model of economic insulation thickness of the buried hot oil pipelines is
built in this paper, which is solved by the golden section method while considering the costs of investment, operation, environment, the time value of money. The
environmental cost… More >
Open Access
ARTICLE
Abdelkarim El Kahoui1, Mustapha Malek1, Nouh Izem1, M. Shadi Mohamed2, Mohammed Seaid3,4,*
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 61-78, 2020, DOI:10.32604/cmes.2020.010874
Abstract We propose a high-order enriched partition of unity finite element
method for linear and nonlinear time-dependent diffusion problems. The solution
of this class of problems often exhibits non-smooth features such as steep gradients and boundary layers which can be very challenging to recover using the conventional low-order finite element methods. A class of steady-state exponential
functions has been widely used for enrichment and its performance to numerically
solve these challenges has been demonstrated. However, these enrichment functions have been used only in context of the standard h-version refinement or
the so-called q-version refinement. In this paper we demonstrate that the… More >
Open Access
ARTICLE
Jian Wang1, 2, Ming Fang3, *, Hui Li1, 2
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 79-106, 2020, DOI:10.32604/cmes.2020.09470
Abstract Structural components may enter an initial-elastic state, a plastic-hardening state
and a residual-elastic state during strong seismic excitations. In the residual-elastic state,
structural components keep in an unloading/reloading stage that is dominated by a tangent
stiffness, thus structural components remain residual deformations but behave in an elastic
manner. It has a great potential to make model order reduction for such structural
components using the tangent-stiffness-based vibration modes as a reduced order basis. In this
paper, an adaptive substructure-based model order reduction method is developed to perform
nonlinear seismic analysis for structures that have a priori unknown damage distribution. This
method… More >
Open Access
ARTICLE
Pengfei Zhu1, Qinghui Zhang2,*
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 107-127, 2020, DOI:10.32604/cmes.2020.09831
Abstract There are several difficulties in generalized/extended finite element
methods (GFEM/XFEM) for moving interface problems. First, the GFEM/XFEM
may be unstable in a sense that condition numbers of system matrices could be
much bigger than those of standard FEM. Second, they may not be robust in that
the condition numbers increase rapidly as interface curves approach edges of
meshes. Furthermore, time stepping schemes need carrying out carefully since
both enrichment functions and enriched nodes in the GFEM/XFEM vary in time.
This paper is devoted to proposing the stable and robust GFEM/XFEM with effi-
cient time stepping schemes for the parabolic interface… More >
Open Access
ARTICLE
Qin Wan1,2,*, Xiaolin Zhu1, Yueping Xiao1, Jine Yan1, Guoquan Chen1, Mingui Sun3
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 129-149, 2020, DOI:10.32604/cmes.2020.09397
Abstract Detecting moving objects in the stationary background is an important
problem in visual surveillance systems. However, the traditional background subtraction method fails when the background is not completely stationary and
involves certain dynamic changes. In this paper, according to the basic steps of
the background subtraction method, a novel non-parametric moving object detection method is proposed based on an improved ant colony algorithm by using the
Markov random field. Concretely, the contributions are as follows: 1) A new nonparametric strategy is utilized to model the background, based on an improved
kernel density estimation; this approach uses an adaptive bandwidth, and… More >
Open Access
ARTICLE
Bufan Chu1,2, Qiwen Liu1,2, Lisheng Liu1,2,3,*, Xin Lai1,2, Hai Mei1,2
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 151-178, 2020, DOI:10.32604/cmes.2020.010115
Abstract In this study, a new bond-based peridynamic model is proposed to
describe the dynamic properties of ceramics under impact loading. Ceramic materials show pseudo-plastic behavior under certain compressive loadings with high
strain-rate, while the characteristic brittleness of the material dominates when it is
subjected to tensile loading. In this model, brittle response under tension, softening plasticity under compression and strain-rate effect of ceramics are considered,
which makes it possible to accurately capture the overall dynamic process of ceramics. This enables the investigation of the fracture mechanism for ceramic materials, during ballistic impact, in more detail. Furthermore, a bond-force updating
algorithm… More >
Open Access
ARTICLE
Chao Mei, Qifu Wang*, Chen Yu, Zhaohui Xia
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 179-202, 2020, DOI:10.32604/cmes.2020.09948
(This article belongs to this Special Issue: Recent Developments of Isogeometric Analysis and its Applications in Structural Optimization)
Abstract This paper presents a topology optimization method for variable stiffness composite panels with varying fiber orientation and curvilinear fiber path.
Non-uniform rational B-Splines (NURBS) based Isogeometric analysis (IGA) is
utilized for the numerical computation of the general minimum compliance problem. The sensitivity analysis of the structure compliance function for the density
and bi-layer orientation is conducted. The bi-layer fiber paths in the design
domain are generated using streamline method and updated by divided pieces
reselection method after the optimization process. Several common examples
are tested to demonstrate the effectiveness of the method. The results show that
the proposed method can… More >
Open Access
ARTICLE
Long Chen1, Li Xu1, Kai Wang1, Baotong Li2,*, Jun Hong2
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 203-225, 2020, DOI:10.32604/cmes.2020.09896
(This article belongs to this Special Issue: Recent Developments of Isogeometric Analysis and its Applications in Structural Optimization)
Abstract The geometric model and the analysis model can be unified together
through the isogeometric analysis method, which has potential to achieve seamless integration of CAD and CAE. Parametric design is a mainstream and successful method in CAD field. This method is not continued in simulation and
optimization stage because of the model conversion in conventional optimization
method based on the finite element analysis. So integration of the parametric modeling and the structural optimization by using isogeometric analysis is a natural
and interesting issue. This paper proposed a method to realize a structural optimization of parametric complex shapes by using isogeometric… More >
Open Access
ARTICLE
Xiangyu Gao, Weidong Yang*, Hongxuan Xian, Xiyuan Tu, Yuanyuang Wang*
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 227-241, 2020, DOI:10.32604/cmes.2020.09923
(This article belongs to this Special Issue: Design & simulation in Additive Manufacturing)
Abstract This paper studies the binder droplet injection process in the 3DP technique. The mathematical model of the binder penetration process for multi-nozzle
and multi-layer in 3DP technique is established, by using the conservation Level
set method. According to the two-dimensional plane model of three-dimensional
spatial structure of sand bed, the construction method of an equivalent cylindrical
mapping infiltration model is proposed to represent the porosity of the model in
the two-dimensional plane, which is exactly the same as that in the three-dimensional
space, as well as closer to the arrangement of the three-dimensional space, and to
realize the differentiation between… More >
Open Access
ARTICLE
Zhiqiang Wang1, Xuede Wang1, Xin Zhou1,*, Guangzhao Ye2, Xing Cheng1,3, Peiyu Zhang1
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 243-263, 2020, DOI:10.32604/cmes.2020.09934
(This article belongs to this Special Issue: Design & simulation in Additive Manufacturing)
Abstract During the selective laser melting process, a high-energy laser beam acts on
the powder, a molten pool is rapidly generated and the characteristic parameters are
constantly changing. Among them, temperature is one of the important parameters
in the forming process. Due to the generation of splash particles, there will be defects
in the microstructure, which will seriously affect the formation quality of the prepared
parts. Therefore, it is necessary to study the relationships between the splash behavior,
molten pool characteristics and product quality. The finite element simulation of the
transient temperature field was performed by ANSYS software. Time-series images
at… More >
Open Access
ARTICLE
Dongsheng Du1,*, Sheng Shi1, Weizhi Xu1, Chen Kong2, Shuguang Wang1, Weiwei Li1
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 265-285, 2020, DOI:10.32604/cmes.2020.09151
(This article belongs to this Special Issue: Numerical Modeling and Simulation for Structural Safety and Disaster Mitigation)
Abstract The intensity non-stationarity is one of the most important features of
earthquake records. Modeling of this feature is significant to the generation of arti-
ficial earthquake waves. Based on the theory of phase difference spectrum, an
intensity non-stationary envelope function with log-normal form is proposed.
Through a tremendous amount of earthquake records downloaded on Kik-net, a
parameter fitting procedure using the genetic algorithm is conducted to obtain
the value of model parameters under different magnitudes, epicenter distances
and site conditions. A numerical example is presented to describe the procedure
of generating fully non-stationary ground motions via spectral representation, and
the… More >
Open Access
ARTICLE
Qigang Sun1, Jian Wu1, Dahai Wang2,*, Yue Xiang2, Haitao Liu1, Xiaobin Sun3
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 287-302, 2020, DOI:10.32604/cmes.2020.09118
(This article belongs to this Special Issue: Numerical Modeling and Simulation for Structural Safety and Disaster Mitigation)
Abstract Downburst event is identified as a major cause to failure of transmission lines in non-coastal regions. In this paper, a novel nonlinear analytical frame
for quasi-static buffeting responses of hinged and multi-span insulator-line systems are derived based on the theory of cable structure. The closed-form solutions
are presented and applied to predict nonlinear response including displacements
and other reactions of the system subjected to a moving downburst wind in a case
study. Accuracy and efficiency of the derived analytical frame are validated via
comparisons with results from finite element method. More >
Open Access
ARTICLE
Yan Li1,2, Dayou Liu1,2, Yungang Zhu1,2, Jie Liu1,2,*
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 303-313, 2020, DOI:10.32604/cmes.2020.09353
(This article belongs to this Special Issue: Data Science and Modeling in Biology, Health, and Medicine)
Abstract Under different conditions, gene regulatory networks (GRNs) of the
same gene set could be similar but different. The differential analysis of GRNs
under different conditions is important for understanding condition-specific gene
regulatory relationships. In a naive approach, existing GRN inference algorithms
can be used to separately estimate two GRNs under different conditions and identify the differences between them. However, in this way, the similarities between
the pairwise GRNs are not taken into account. Several joint differential analysis
algorithms have been proposed recently, which were proved to outperform the
naive approach apparently. In this paper, we model the GRNs under different… More >
Open Access
ARTICLE
Xinshuai Shi1, Hongwen Jing1, *, Jianguo Ning2, Zhenlong Zhao1, Junfu Zhu1
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 315-343, 2020, DOI:10.32604/cmes.2020.07955
(This article belongs to this Special Issue: Modeling and Simulation of Fluid flows in Fractured Porous Media: Current Trends and Prospects)
Abstract The stability control of gob-side entry retaining in fully mechanized caving face
is a typical challenge in many coal mines in China. The rotation and subsidence of the
lateral cantilever play a critical role in a coal mine, possibly leading to instability in a coal
seam wall or a gob-side wall due to its excessive rotation subsidence. Hence, the presplitting
blasting measures in the roof was implemented to cut down the lower main roof and convert
it to caved immediate roof strata, which can significantly reduce the rotation space for the
lateral cantilever and effectively control its rotation. Firstly, the… More >
Open Access
ARTICLE
Qian Yin1,2, Xiaojing Li3,*, Liyuan Yu1, Ming He1, Richeng Liu1,2
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 345-373, 2020, DOI:10.32604/cmes.2020.08204
(This article belongs to this Special Issue: Modeling and Simulation of Fluid flows in Fractured Porous Media: Current Trends and Prospects)
Abstract An experimental and numerical study was carried out to investigate the
solute removal process through a large-scale fracture plane considering different
flow paths and hydraulic head differences. The visualization techniques were utilized in the experiment to capture the removal process images, which were then
transferred to binary images. The variations in dimensionless concentration,
which is defined as saturation of solute phase, were analyzed. With increasing
hydraulic head difference, the speed of solute removal increases and the dimensionless concentration decreases. The flow paths result in different solute distribution patterns and different mechanisms for solute removal such as advection and
diffusion, thus… More >
Open Access
ARTICLE
Hongtao Wang1,2,*, Ping Liu1,2, Lige Wang3,4,*, Chi Liu5, Xin Zhang1,2, Luyao Liu1,2
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 375-391, 2020, DOI:10.32604/cmes.2020.08270
(This article belongs to this Special Issue: Modeling and Simulation of Fluid flows in Fractured Porous Media: Current Trends and Prospects)
Abstract Layered rock strata are observed to be common during the excavation
of tunnels or cavities, and may significantly affect the deformation and failure
characteristics of surrounding rock masses due to various complex forms and
mechanical properties. In this paper, we propose a three-dimensional axisymmetric velocity field for roof collapse of shallow cavities in multi rock layers,
by considering the influences of roof cross-section shapes, supporting pressure,
ground overload, etc. The internal energy dissipation rate and work rates of external forces corresponding to the velocity field are computed by employing the
Hoek-Brown strength criterion and its associated flow rule. Further, the… More >
Open Access
ARTICLE
Fengyong Li1, *, Zongliang Yu1, Chuan Qin2
CMES-Computer Modeling in Engineering & Sciences, Vol.124, No.1, pp. 393-410, 2020, DOI:10.32604/cmes.2020.09452
(This article belongs to this Special Issue: Information Hiding and Multimedia Security)
Abstract This paper proposes a new constructive texture synthesis steganographic scheme
by compressing original secret messages. First, we divide the original message into multiple
bit blocks, which are transferred to decimal values and compressed into small decimal values
by recording their interval sign characters. Then, a candidate pattern is generated by
combining the given source pattern and boundary extension algorithm. Furthermore, we
segment the candidate pattern into multiple candidate patches and use affine transformation
algorithm to locate secret positions on a blank canvas, which are used to hide the sign
characters by mapping the candidate patches. Finally, we select the candidate… More >