Search results for "T method"

Estimation of hydrodynamic properties of a sandy-loam soil by two analysis methods of single-ring infiltration data

2022

Abstract Beerkan infiltration runs could provide an incomplete description of infiltration with reference to either the near steady-state or the transient stages. In particular, the process could still be in the transient stage at the end of the run or some transient infiltration data might be loss. The Wu1 method and the BEST-steady algorithm can be applied to derive soil hydrodynamic parameters even under these circumstances. Therefore, a soil dataset could be developed using two different data analysis methods. The hypothesis that the Wu1 method and BEST-steady yield similar predictions of the soil parameters when they are applied to the same infiltration curve was tested in this investi…

Quasi-Newton approach to nonnegative image restorations

2000

Abstract Image restoration, or deblurring, is the process of attempting to correct for degradation in a recorded image. Typically the blurring system is assumed to be linear and spatially invariant, and fast Fourier transform (FFT) based schemes result in efficient computational image restoration methods. However, real images have properties that cannot always be handled by linear methods. In particular, an image consists of positive light intensities, and thus a nonnegativity constraint should be enforced. This constraint and other ways of incorporating a priori information have been suggested in various applications, and can lead to substantial improvements in the reconstructions. Neverth…

Building energy performance forecasting: A multiple linear regression approach

2019

Abstract Different ways to evaluate the building energy balance can be found in literature, including comprehensive techniques, statistical and machine-learning methods and hybrid approaches. The identification of the most suitable approach is important to accelerate the preliminary energy assessment. In the first category, several numerical methods have been developed and implemented in specialised software using different mathematical languages. However, these tools require an expert user and a model calibration. The authors, in order to overcome these limitations, have developed an alternative, reliable linear regression model to determine building energy needs. Starting from a detailed …

B-Deformable Superquadrics for 3D Reconstruction

1995

We propose a new model for 3D representation and reconstruction. It is based on deformable superquadrics and parametric B-Splines. The 3D object deformation method uses B-Splines, instead of a Finite Element Method (FEM). This new model exhibits advantages of B-Splines It is significantly faster than deformable superquadrics without loss of generality (no assumption is made on object shapes,).

The MAST-FV/FE scheme for the simulation of thermohaline processes in variable density saturated porous media

2009

A novel methodology for the simulation of 2D thermohaline double diffusive processes, driven by heterogeneous temperature and concentration fields in variable-density satu- rated porous media, is presented. The stream function is used to describe the flow field and it is defined in terms of mass flux. The partial differential equations governing system is given by the mass conservation equation of the fluid phase written in terms of the mass- based stream function, as well as by the advection–diffusion transport equations of the contaminant concentration and of the heat. The unknown variables are the stream func- tion, the contaminant concentration and the temperature. The governing equatio…

The MAST-FV/FEM scheme for the simulation of thermohaline processes in density-variable saturated porous media

2008

Finite Element Method and Von Mises Investigation on Bone Response to Dynamic Stress with a Novel Conical Dental Implant Connection

2020

The bioengineering and medical and biomedical fields are ever closer, and they manage to obtain surprising results for the development of new devices. The field of simulations and studies in silica has undergone considerable development in recent years, favoring the advancement of medicine. In this manuscript, a study was carried out to evaluate the force distribution on the implant components (In-Kone® Universal) and on the peri-implant tissues subjected to loading. With the finite element analysis and the Von Mises method, it was possible to evaluate this distribution of forces both at 0 degrees (occlusal force) and at 30 degrees; the applied force was 800 N. The obtained results on this …

Comparative analysis of numerical and experimental data of orthodontic mini-implants

2011

The purpose of this study was to compare numerical simulation data derived from finite element analysis (FEA) to experimental data on mini-implant loading. Nine finite element (FE) models of mini-implants and surrounding bone were derived from corresponding experimental specimens. The animal bone in the experiment consisted of bovine rib. The experimental groups were based on implant type, length, diameter, and angle of insertion. One experimental specimen was randomly selected from each group and was digitized in a microCT scanner. The FE models consisted of bone pieces containing Aarhus mini-implants with dimensions 1.5 × 7 mm and 1.5 × 9 mm or LOMAS mini-implants (dimensions 1.5 × 7 mm, …

Biomechanical behavior of cavity configuration on micropush-out test: A finite-element-study

2009

Objective: The objective of this study was to simulate the micropush-out bond strength test from a biomechanical point of view. For this purpose, stress analysis using finite element (FE) method was performed. Study design: Three different occlusal cavity shapes were simulated in disc specimens (model A: 1.5 mm cervical, 2 mm occlusal diameter; model B: 1.5 mm cervical, 1.75 mm occlusal diameter; model C: 1.5 mm cervical, 1.5 mm occlusal diameter). Quarter sizes of 3D FE specimen models of 4.0×4.0×1.25 mm3 were constructed. In order to avoid quantitative differences in the stress value in the models, models were derived from a single mapping mesh pattern that generated 47.182 elements and 6…

Premolars restored with posts of different materials: fatigue analysis

2011

Previous works studied the effect of the material and the dimensions of the post on the biomechanical performance (fracture strength and stress distribution) of restored teeth, under static loads. The aim of this work was to study the effect of the post material (glass fibre and stainless steel) on restored teeth, which have the final crown, under dynamic conditions. The use of a biomechanical model, including a fatigue analysis from FEA, is presented as a powerful method to study the effect of the material of the intraradicular post. The inclusion of the fatigue analysis allows for a more realistic study that takes into account the dynamic nature of masticatory forces. At the same time, th…