A Neural Element Method

2020 ◽  
Vol 17 (07) ◽  
pp. 2050021
Author(s):  
G. R. Liu

Methods of artificial neural networks (ANNs) have been applied to solve various science and engineering problems. TrumpetNets and TubeNets were recently proposed by the author for creating two-way deepnets using the standard finite element method (FEM) and smoothed FEM (S-FEM) as trainers. The significance of these specially configured ANNs is that the solutions to inverse problems have been, for the first time, analytically derived in explicit formulae. This paper presents a novel neural element method (NEM) with a focus on mechanics problems. The key idea is to use artificial neurons to form elemental units called neural-pulse-units (NPUs), using which the shape functions can then be constructed, and used in the standard weak and weakened-weak (W2) formulations to establish discrete stiffness matrices, similar to the standard FEM and S-FEM. Theory, formulation and codes in Python are presented in detail. Numerical examples are then used to demonstrate this novel NEM. For the first time, we have made a clear connection in theory, formulations and coding, between ANN methods and physical-law-based computational methods. We believe that this novel NEM fundamentally changes the way of approaching mechanics problems, and opens a window of opportunity for a range of applications. It offers a new direction of research on unconventional computational methods. It may also have an impact on how the well-established weak and W2 formulations can be introduced to machine learning processes, for example, creating well-behaved loss functions with preferable convexity.

Author(s):  
Er. Hardik Dhull

The finite element method is a numerical method that is used to find solution of mathematical and engineering problems. It basically deals with partial differential equations. It is very complex for civil engineers to study various structures by using analytical method,so they prefer finite element methods over the analytical methods. As it is an approximate solution, therefore several limitationsare associated in the applicationsin civil engineering due to misinterpretationof analyst. Hence, the main aim of the paper is to study the finite element method in details along with the benefits and limitations of using this method in analysis of building components like beams, frames, trusses, slabs etc.


Mathematics ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 920
Author(s):  
Chukwuma Ogbonnaya ◽  
Chamil Abeykoon ◽  
Adel Nasser ◽  
Ali Turan

A system of transcendental equations (SoTE) is a set of simultaneous equations containing at least a transcendental function. Solutions involving transcendental equations are often problematic, particularly in the form of a system of equations. This challenge has limited the number of equations, with inter-related multi-functions and multi-variables, often included in the mathematical modelling of physical systems during problem formulation. Here, we presented detailed steps for using a code-based modelling approach for solving SoTEs that may be encountered in science and engineering problems. A SoTE comprising six functions, including Sine-Gordon wave functions, was used to illustrate the steps. Parametric studies were performed to visualize how a change in the variables affected the superposition of the waves as the independent variable varies from x1 = 1:0.0005:100 to x1 = 1:5:100. The application of the proposed approach in modelling and simulation of photovoltaic and thermophotovoltaic systems were also highlighted. Overall, solutions to SoTEs present new opportunities for including more functions and variables in numerical models of systems, which will ultimately lead to a more robust representation of physical systems.


2017 ◽  
Vol 2017 ◽  
pp. 1-12
Author(s):  
Jui-Hsiang Kao

This research develops an Advance-Tracing Boundary Element Method in the time domain to calculate the waves that radiate from an immersed obstacle moving with random acceleration. The moving velocity of the immersed obstacle is multifrequency and is projected along the normal direction of every element on the obstacle. The projected normal velocity of every element is presented by the Fourier series and includes the advance-tracing time, which is equal to a quarter period of the moving velocity. The moving velocity is treated as a known boundary condition. The computing scheme is based on the boundary integral equation in the time domain, and the approach process is carried forward in a loop from the first time step to the last. At each time step, the radiated pressure on each element is updated until obtaining a convergent result. The Advance-Tracing Boundary Element Method is suitable for calculating the radiating problem from an arbitrary obstacle moving with random acceleration in the time domain and can be widely applied to the shape design of an immersed obstacle in order to attain security and confidentiality.


2008 ◽  
Vol 400-402 ◽  
pp. 329-334
Author(s):  
Ze Liang Yao ◽  
Zhen Jian ◽  
Guo Liang Bai

It is difficult and important to accurately calculate single pile ultimate bearing capacity during pile foundation design. Typical computational methods on single pile ultimate bearing capacity are contrastively analyzed in this paper. Contact element method on single pile ultimate bearing capacity is relatively accurate and economical, but it isn’t used in practical projects until now because its computational process is complicated. 343 different single pile ultimate bearing capacities are calculated with the contact element method in order to study a simple computational formula based on the contact element method. All data calculated are analyzed with a linear recursive multi-analysis program which is programmed with Fortran90. A simple computational formula on the contact element method is presented based on the analysis results. The simple computational formula, the experiential formula in the code, the contact element method and the static load experiment method are respectively used to calculate single pile ultimate bearing capacity in two practical projects in order to test the simple computational formula. The results show that the simple computational formula is relatively accurate. Some advice is presented based on the analysis results.


2017 ◽  
Vol 53 (27) ◽  
pp. 3830-3833 ◽  
Author(s):  
Andreia de Almeida ◽  
Andreia F. Mósca ◽  
Darren Wragg ◽  
Margot Wenzel ◽  
Paul Kavanagh ◽  
...  

The mechanism of inhibition of water and glycerol permeation via human aquaglyceroporin-3 (AQP3) by gold(iii) complexes has been described, for the first time, using molecular dynamics (MD), combined with density functional theory (DFT) and electrochemical studies.


Author(s):  
Mohammad Reza Rahimi ◽  
Seyed Davoud Mohammadi ◽  
Alireza Taleb Beydokhti

The literature review confirms that the effect of mineral composition on the strength properties of rocks has rarely been studied. One of the most problematic sedimentary rocks is sulfate rocks, which cause engineering problems in the infrastructure sites such as reservoir dams. In this paper, for the first time, the effect of mineral composition on the strength properties of sulfate rocks was investigated. The rock blocks were collected from the Gachsaran Formation outcrops at the four under construction reservoir dam sits in Iran. After preparing, drying and saturation the rock cores samples (329 samples), uniaxial compressive strength tests were performed in accordance with ASTM and ISRM standards. The results of this study confirmed that firstly, there is a correlation between the mineral composition and the strength properties of the sulfate rocks, but the obtained relationships do not have the necessary certainty to be used as predictive equations. Secondly, by increasing the amount of anhydrite or microcrystalline carbonates in a gypsum rock, its strength properties are increased. Thirdly, in a dry condition the dominant failure mode in gypsum and anhydrite rocks is a shear and dilatation mode, respectively, but after saturation, the failure mode tends to shear mode.


Sign in / Sign up

Export Citation Format

Share Document