BACKGROUND Radiolucent lines and sclerotic margins are often seen on knee radiographs taken a year or longer after knee replacement surgery. Histology has shown that the radiolucent zone is predominantly fibrocartilage and the sclerotic margin is lamellar bone. The reasons for their existence are not clearly understood. METHODS A three-dimensional finite element model of the medial half of th...

We investigated the deformation of the viscoelastic polymethyl methacrylene (PMMA) resist wherein a rigid SiO2 stamp with a rectangular line pattern is imprinted for thermal nano-imprint lithography (NIL). We calculated the stress distribution in the polymer resist during the molding process by finite element method (FEM). Our simulation results revealed asymmetric von Mises stress distribution...

INTRODUCTION The objective of this study was to demonstrate the potential of 3-dimensional modeling and finite element analysis as clinical tools in treatment planning for orthodontic tooth movement. High stresses in bone and miniscrew implants under load can cause fractures and trauma for orthodontic patients, and treatments are typically planned by using clinical experience or simple 2-dimens...

The purpose of this study was to compare the fracture resistance and fracture mode of single implant-zirconium coping combinations using zirconium and titanium abutments and to analyze the stress distribution pattern using three-dimensional finite elements analysis. Twenty implants with titanium and zirconium abutments were randomly divided into two groups (n = 10) and into resin blocks. Zircon...

J Korean Assoc Oral Maxillofac Surg 2012;38:271-5) Objectives: This study evaluated a range of fixation methods to determine which is best for the postoperative stabilization of a mandibular osteotomy using three-dimensional finite element analysis of the stress distribution on the plate, screw and surrounding bone and displacement of the lower incisors. Materials and Methods: The model was gen...

Most of the tractable distributions currently available for modeling circular data are symmetric around a modal direction, prominent among them the von Mises distribution. Here we discuss a method of introducing asymmetry into any such symmetric circular model and develop general classes of non-symmetric circular distributions. In particular, we introduce and study a resulting variation of the ...

This paper presents a summary of the new semi-analytical integration method presented in [10] for von Mises elastoplasticity model with combined linear isotropic-kinematic hardening within a small deformation range. Solutions for the case of constant strain rate and constant stress rate assumptions are also presented. Furthemore, it is shown how the general solution reduces to the particular ca...

A finite element model has been developed to simulate nonlinear response of piles/drilled piers under axial loading. The nonlinear stress-strain behaviors of soils are modeled via Drucker-Prager and von Mises type plasticity. A parametric study is carried out to address the influence of various factors, such as soil friction approximation, dilatancy, effect of interface element and shear streng...

This paper proposes a suite of models for clustering high-dimensional data on a unit sphere based on von Mises-Fisher (vMF) distribution and for discovering more intuitive clusters than existing approaches. The proposed models include a) A Bayesian formulation of vMF mixture that enables information sharing among clusters, b) a Hierarchical vMF mixture that provides multiscale shrinkage and tre...

Finite mixtures of von Mises-Fisher distributions allow to apply model-based clustering methods to data which is of standardized length, i.e., all data points lie on the unit sphere. The R package movMF contains functionality to draw samples from finite mixtures of von Mises-Fisher distributions and to fit these models using the expectation-maximization algorithm for maximum likelihood estimati...