A newly-developed, dimensionally reduced, hp-type axisymmetric shell finite element model is extended to linear elastodynamic problems of thin shells of revolution. The hp-shell finite element relies on the hybridized version of a three-field dual-mixed variational formulation, the application of which dictates the obligate usage of the inverse three-dimensional constitutive relation for homogeneous

Uncertainties play an important role in dynamic systems regarding their vibration and wave propagation behaviour. Stochastic methods have been used to address the randomness incorporated in numerical models. The spectral element method (SEM) is suitable to perform vibration and wave propagation analysis based on large frequency ranges with accuracy and low computational cost. This paper explores the

In the analytic modeling of shell buckling, much attention has been paid to closed cylindrical shells or cylindrical panels with at least two opposite edges simply supported whose solutions are known to be Lévy-type solutions. However, there have been very few reports on analytic solutions of commonly used non-Lévy-type cylindrical panels, which is mainly attributed to the widely acknowledged difficulty

Thin surfaces, such as the leaves of a plant, pose a significant challenge for implicit surface reconstruction techniques, which typically assume a closed, orientable surface. We show that by approximately interpolating a point cloud of the surface (augmented with off-surface points) and restricting the evaluation of the interpolant to a tight domain around the point cloud, we need only require an

The use of Active Flow Control (AFC) technologies to modify the forces acting on streamlined bodies is one of the most active research fields in aerodynamics. For each particular application, finding the optimum set of AFC parameters which maximises lift, minimises drag or maximises lift-to-drag ratio (aerodynamic efficiency), has become a necessary design requirement. In the present paper, the AFC

In this paper, we propose a level set-based topology optimization method for the unit-cell design of acoustic metasurfaces by using a two-scale homogenization method. Based on previous works, we first propose a homogenization method for acoustic metasurfaces that can be combined with topology optimization. In this method, a nonlocal transmission condition depending on the unit cell of the metasurface

We propose a method based on a global anisotropic gradient prior (GAGP) for addressing the problem of rain streak removal. We observe that both images and rain streaks have anisotropy at edges, and that the rain distribution in images is sparse. We therefore propose an L0-regularized sparse term with an L0-regularized GAGP term to efficiently detect the rain streaks. We applied the L0-regularized GAGP

To improve the robustness of the film/substrate-type stretchable electronics, an intermediate layer has been adopted in their design in recent years. However, the intermediate layer could significantly influence the static and dynamic behaviours of the tri-layer structure (film/intermediate layer/substrate structure). In this paper, considering the shear stress between the film and intermediate layer

Log transportation in the forest industry is a key issue for the success of any firm. This operation involves complex decision making, requiring suitable approaches with high computational performance. The main decisions to be considered are related to the fleet size and log supply to minimize transportation costs. Thus, the number of vehicles to be used, the harvest areas that supply each plant and

This paper examines the interface elasticity between an elastic half-space and a spherical nanoinhomogeneity subjected to a unidirectional far-field tension that is parallel to the half-space plane boundary. The spherical interface is modeled by the full version of Steigmann–Ogden interface theory. Due to their marginal significance, the effects of half-space plane boundary are neglected. The problem

The long-term leakage of lining under train loading has a significant impact on the consolidation settlements around shield tunnel and the rheological behavior of viscoelastic porous soils will further exacerbate this consequence, which adversely affect the adjacent geo-environments and the subsidence of existing structures. At present, the assumptions of tunnel impermeable lining and liner-elastic

The Large Eddy Simulation approach was used to perform a numerical simulation of a flow around a circular tube bundle. The model is based on numerical tools, such as the immersed boundary technique and the extrapolation of pressure in the solid region of the tube, to represent a helical segmented-fin tube geometry. The simulation was conducted in an area away from the boundaries of the tube bundle

In this paper, a temperature and size-dependent molecular model is proposed to calculate the mechanical properties of carbon nanotubes. The cross section of carbon nanotubes is regarded as a hexagonal ring structure, and the covalent bond between carbon atoms is regarded as a beam of nonlinear spring structure, that is, the molecular structure system is regarded as a "beam-helical spring" structure

A new analytical approach is presented for gravity-induced stresses in elastic half plane with a slope. The half plane is mapped onto the unit circle in ζ plane by conformal transformations. The mapping function proposed by Schwarz-Christoffel is irrational and difficult to be applied to the problem in the paper. Therefore, the explicit expression of the mapping function, which is easy to use and has

Large measurement errors are a major challenge in structural model updating. Based on the concept of homotopy, a new stochastic static model updating method is proposed to update structural models using uncertain static data with large measurement errors. First, considering the uncertainty of the static measurement, a stochastic model updating equation for element update factors is set up. To solve

Considering the multi-sources, heterogeneity and complexity of dam anomaly assessment, a novel anomaly assessment model based on sequential variational autoencoder and evidence theory is proposed to perform dam anomaly assessment. The anomaly assessment model consists of two stages: anomaly detection and anomaly fusion. At the stage of anomaly detection, a novel sequential variational autoencoder is

This paper presents an efficient fragility analysis approach for offshore structures subjected to random wave load considering parameter uncertainty. Fragility analysis of structures under random dynamic load is generally accomplished by the direct Monte Carlo simulation (MCS), which requires extensive computational time. Hence, in the present study, a new cumulative distribution function matching-based

This paper suggests a simple approach to examine the local behavior of the velocity and the shear stresses in the vicinity of a triple point (TP) of two-phase flow. We assume a laminar steady, fully developed, stratified two-phase flow with any contact angle, α, independent of the tube cross-section shape. The axial component of the fluid’s velocity can be considered as a scalar function in two dimensions

An original formulation for the elastic analysis of multilayered shells is presented in this work. The key features of the formulation are: the representation of the shell mean surface via a generic system of curvilinear coordinates; the unified treatment of general shell theories via an Equivalent-Single-Layer approach based on the through-the-thickness expansion of the covariant components of the

To use effectively the shell in high-performance applications, analyzing the effect of hygrothermal effects on a piezoelectric delamination event is necessary. A laminated piezoelectric cylindrical shell with delamination is first established under hygrothermal effects, followed by an internal force analysis and an energy analysis of the shell. Then, a parametric vibration equation of the Mathieu for

In this article, the estimation of the unknown parameters and the survival and hazard functions of Weibull distribution is studied with the adaptive Type-II progressively censored competing risks data, where the lifetime random variables of the individual failure causes are independent and follow Weibull distribution with different scale and shape parameters. For frequentist estimation, the maximum

Unlike the widely used eigen-buckling theory, the nonlinear post-buckling analysis provides a more accurate stability model of piezoelectric cylindrical shells and predicates more reliable instability characteristics. In this paper, an accurate post-buckling analysis of piezoelectric functionally graded cylindrical shells under combined electro-thermo-mechanical loadings is performed. The nonlinear

Since the failure modes of fully grouted bolts subject to displacements of rock joints are difficult to predict, the joint displacements in this study are categorised into two types: opening displacement and shear displacement. At first, a closed-form solution incorporating the nonlinear constitutive model of interfaces between bolts and grout is developed, which is able to formulate the full-range

An improved explicit time integration method is proposed for linear and nonlinear dynamics. Its calculation procedure is obtained with cubic B-spline interpolation approximation and weighted residual method. In the formulation, a momentum corrector is used to improve actual computation accuracy, especially for some special discontinuous loads. Analytical solutions of the local truncation errors, algorithmic

In this paper, a hybrid algorithm was proposed for multi-objective optimization design with high efficiency and low computational cost based on the Gaussian process regression and particle swarm optimization algorithm. For the proposed method, the global performance indices, including regular workspace volume, global transmission index, global stiffness index, and global dynamic index were considered

It is crucial to predict the worst surface accuracy of deployable mesh reflectors considering uncertainties at the design stage. The traditional method is computationally expensive because a form-finding process which needs many iterations is required in each Monte Carlo simulation. A quick method is adopted to rapidly compute the worst surface accuracy of deployable mesh reflectors. The sensitivity

The coupling of mesoscale and microscale simulation methods represents a significant challenge of wind energy research. Conventional approaches used to address this problem often combine Reynolds-averaged Navier-Stokes (RANS) and large eddy simulation (LES) equation elements, which has two significant disadvantages. First, Wyngaard’s Terra Incognita challenge cannot be addressed because there is no

To generate continuing profits as well as to retain market share, companies need to regularly introduce new products into the market, replacing outdated products and enticing buyers to purchase new products. Thus, planning the product transition from the phase-out of a product to the phase-in of a product is a challenging task for both production planners and marketing managers. One significant concern

Organization and planning of reverse logistics networks make sustainable processes more efficient. Thus, an important sector for connecting the collection and waste paper recycling echelons is the intermediate center. In this study, a Mixed Integer Linear Programming model, which is multi-objective, multi-product, multi-level and multi-period, was developed to optimize the waste paper logistics processes

A theoretical model considering the interface shear deformation is developed to investigate the bending properties of graphene substrates coated with nano-film. This paper presents a closed-form solution for predicting the bending properties of graphene substrates coated with nano-film. Based on the proposed model, we investigate the effects of the interface shear stiffness and the boundary conditions

With increasing competition in the pharmaceutical industry, pharmaceutical companies pay more attention to improving the efficiency of clinical trial supply chains to reduce the drug supplying cost, which takes up a considerable part of the total research and development expense. To improve the efficiency of clinical trial supply chains, this study investigates the inventory levels of clinical drugs

A quantized fixed-time fault-tolerant attitude control problem for hypersonic reentry vehicles is considered from the perspective of practical engineering. Taking into account the limited time available for recovery from a fault scenario, fixed-time extended state observers are used to simultaneously compensate for the negative effect of unknown time-varying actuator faults, uncertainties, and external

The post-buckling of a clamped column made of nonlinear elastic material and subject to axial compression is investigated in this paper. The Ramberg−Osgood type constitutive relation is adopted and it is expanded by using Taylor series. Based on Euler−Bernoulli beam theory, the exact governing equations are expressed in terms of rotation angle. Because the equations contain strongly nonlinear terms

This paper looks at the method of Medvedev and Scaillet at pricing short-term American options and provides an improved representation of their series solution in which explicit formulae for the coefficients are provided. This then avoids the need for solving complicated, recursive systems and efficiently provides fast solutions. We also compare the method with well-known existing methods and find

In this paper, a molecular dynamics (MD)-based multiscale analysis is employed to investigate the free vibration of graphene reinforced laminated composite plates from the atomic scale to the macroscopic behavior. The atomic models of graphene with different sizes, poly (methyl methacrylate) (PMMA) and graphene/PMMA composites with different graphene volume fractions are constructed, and Poisson's

Mathematical models have been developed to investigate the quantitative behaviour of the current and power distributions in large submerged arc furnaces, usually fed by a low-frequency alternating source. Reduced 2D and 1D models will be used to investigate the electrical behaviour inside the furnace; in particular, these models will allow us to explain the inductive effects between the different regions

The accurate calculation of the mesh stiffness for a plastic gear pair is significant for analyzing its transmission performance. During the meshing process, factors such as gear tooth meshing deformation and thermal effect will cause variations of the meshing position and tooth load particularly for plastic gears. These increase the difficulty for the accurate calculation of the gear mesh stiffness

This article focuses on the transformation and development of traditional industries in the context of digital economy. The Hamilton-Jacobi-Berman equation is used to investigate the coordination mechanism and optimal strategy of industrial integration from a quantitative perspective and examine the dynamic decision-making processes among traditional enterprises, digital technology providers, and local

Semi-competing risks data, including probably correlated non-terminal event and terminal event times, are frequently encountered in medical research. Work on semi-competing risks data has mainly focused on the situations without or only with low-dimensional covariates. However, high and ultra-high dimensional data have been very common in modern scientific research. In this article, we propose a model-free

One of the important aspects in improving the efficiency of electrochemical processes, such as water electrolysis, is the efficient removal of bubbles which evolve from the electrodes. Numerical modelling based on Computational Fluid Dynamics (CFD) can describe the process, provide insights into its complexity, elucidate the underlying mechanisms of how bubbles evolve and their effect as well as aid

Triangular mesh has been a prevalent form of 3D model representation in various areas ranging from modeling to finite element analysis due to their simplicity and flexibility. In the paper, we present a triangular mesh remeshing method based on a sphere packing method and a node insertion/deletion method for surface meshes. First, a new set of nodes are generated on the surface mesh via a sphere packing

Feature selection (FS) is a crucial step for effective data mining since it has largest effect on improving the performance of classifiers. This is achieved by removing the irrelevant features and using only the relevant features. Many metaheuristic approaches exist in the literature in attempt to address this problem. The performance of these approaches differ based on the settings of a number of

This paper is focused on a fast and reliable estimate of anchor energy losses from a Micro-Electro-Mechanical System resonator, working at pressure in the order of the microbar, due to the scattering of elastic waves from the resonator into the substrate to which it is attached. The proposed numerical method is based on the fundamentals of the analytical procedure employed to estimate quality factors

This paper investigates, for the first time, the thermo-elastic responses of a functionally graded (FG) graphene nanoplatelets (GPLs) reinforced composite (FG-GPLRC) closed cylindrical shell under a temperature field due to steady-state thermal conduction along thickness direction. A comprehensive thermo-elastic model covering various thermal boundary conditions (TBCs) is established. Analytical solutions

Transportation is one of the most influential factors in greenhouse gas emissions and global warming. This paper studies a network with an automotive supply chain that includes one supplier and one manufacturer next to a fuel supply chain consisting of a fuel manufacturer, operating under government intervention. The car manufacturer sells its green and non-green products under the dual-channel system

For materials that have a matrix porosity at the microscopic scale, and an interconnecting fracture system at the mesoscopic scale, the double-porosity dual-permeability model provides a better prediction of seismic wave attenuation than the single porosity model, due to the flow exchange mechanism between these different size pores. The current work offers for the first time a numerical solution tool

We derive the expressions for the collision-induced amplitude dynamics of two flat-top solitons in spatial dimensions of 1, 2, and 3 caused by the generic weak nonlinear loss under the framework of coupled cubic-quintic (n+1)D nonlinear Schrödinger equations for n=1,2,3. We develop a new perturbative technique which is mainly based on the calculations for the fast collision-induced changes in the soliton

Based on the asymptotic solutions for primer and gradient fields, two novel semi-analytical elements are respectively proposed to evaluate potential and flux density in the 2D domain with singularity. By setting two semi-analytical elements on both sides of the singular point, the physical fields in the vicinity of the singular point can be simulated, while boundary element method is implemented for

In this paper, a new direct discrete approximation based internal model control design is proposed to the linear discrete dynamical systems. The approximation method is used to determine an accurate and stable reduced-order model for the considered original higher-order discrete-time system. The method involves an enhanced Differential Evolution algorithm to ascertain the stable denominator polynomial

Unbalance in rotors is known as the primary source of excitation, the state of unbalance changes over time and, therefore, industrial rotors require online or smart identification and attenuation of unbalance for smooth operation. To begin with, this paper proposes the use of Active Magnetic Bearings (AMBs) to identify the unbalance. Unbalance is defined as the location of centre of mass of the rotor

The use of constant order differential equations to describe the evolution of complex systems is often unable to describe some of the changing characteristics of the systems accurately. Variable order fractional derivatives provide us with new tools to solve such problems. In this paper, the accumulation and derivative orders of the classic grey model are expanded from constants to functions, and a

To improve the performance of agricultural water resources and food production against a background of China's agricultural water price reform, an interval two-stage stochastic programming model is established and applied to account for impacts of agricultural water price reform and a water-saving technology subsidy in Heilongjiang Province, China. A water price affordability constraint and a water-saving

In this study, in order to reduce the morbidity and improve the structural stability of the existing grey multivariable convolution forecasting model, a new derived multivariable grey model based on the derivation method, abbreviated as DMGM (1, n), is presented. Firstly, the time response formula of DMGM (1, n) is deduced by derivation method, which can avoid solving the inverse matrix so as to reduce

This paper presents a new method to efficiently approximate both linear buckling loads and associated mode shapes of finite element structures subject to perturbations. To achieve this, a coupling between a Reduced Order Model (ROM) based on the Homotopy Perturbation Method (HPM) and a Kriging model is presented here. The ROM maintains the link between eigenvalues, related eigenvectors and the dependencies

In this study the relationship between two families of pairwise associated functions, describing boundary wetting and drying curves, is modelled. This relationship includes both regular and random constituents, and it is represented by a limited dataset of N known pairs of these curves, which pertain to N different soils. Using the dependent domain theory of hysteresis, we show that the regular constituent

Numerical modeling of upstream propagation of a positive surge wave in an open-channel flow caused by a sudden rise of downstream water level, either by gate operation or by tidal influence, remains an important challenge from many aspects. A perusal of literature suggests that the Serre-Green-Naghdi (SGN) models have not been methodically explored for a positive surge flow modeling. In this study

Melting or re-melting accompanies solidification in many technical castings. For example, during ingot casting, some crystal fragments or equiaxed grains can enter the superheated region and re-melt, while solidification continues in other regions. Solidification and remelting occurring simultaneously at different locations present an important species/energy transport mechanism, which impacts the

The nonlinearity of bending stiffness caused by inter-wire slippage has become the major challenge in the prediction of strand bending behavior. This paper proposed an analytical approach to predict the hysteretic bending behavior of helical strands. As an extension of classical models, this paper additionally considered the wire slippage delayed by bending load. Moreover, the method of integral for

The human movement plays an important role in the spread of infectious diseases. On an urban scale, people move daily to workplaces, schools, among others. Here, we are interested in exploring the effect of the daily local stay on the variations of some characteristics of dengue dynamics such as the transmission rates and local basic reproductive numbers. For this, we use a two-patch mathematical model

In this paper, the out-of-plane and in-plane displacements coupled behavior of the transverse and planar vibration characteristics for piezoceramic disks under fully-clamped and traction-free boundary conditions are investigated theoretically base on the Mindlin's and Kirchhoff's plate models. By varying the radius-to-thickness ratios, the piezoceramic disks with moderate and thin thickness are considered