Comparing Isotropic and Anisotropic Brain Conductivity Modeling: Planning Optimal Depth-Electrode Placement in White Matter for Direct Stimulation Therapy in an Epileptic Circuit
L. C. Zaragoza, B. Hondorp, M. A. Rossi
ITESM, Monterrey, Mexico
Rush Medical College, Chicago, IL, USA
Rush University Medical Center, Chicago, IL, USA
The goal of our work was to calculate a patient-specific brain conductivity map for predicting the extent to which direct stimulation therapy can strategically propagate through pathological white matter. Our laboratory developed isotropic and anisotropic human brain finite element method (FEM) models derived from SPGR magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI), ...
A Multiphase Porous Medium Transport Model with Distributed Sublimation Front to Simulate Vacuum Freeze Drying
A. Warning, J. M. R. Arquiza, A. K. Datta
Cornell University, Ithaca, NY, USA
A continuum, porous medium formulation with non-equilibrium sublimation was developed and validated for freeze drying without and with uniform microwave volumetric heating. The model incorporates the effect of Knudsen flow at low pressure and low permeability freeze drying. The distributed, non-equilibrium sublimation demonstrated that the sublimation front is a sharp boundary for high ice ...
M. K. Gobbert, X. Huang, S. Khuvis, S. Askarian, B. E. Peercy
University of Maryland - Baltimore County, Baltimore, MD, USA
This paper presents information on techniques needed in COMSOL Multiphysics® to enable computational studies of coupled systems of PDEs for time-dependent non-linear problems. Furthermore, we demonstrate how to use data files as input for initial conditions. To illustrate the techniques, we consider a system of two time-dependent non-linear PDEs from mathematical biology that couples an ...
C. Gavrila, A. Ghiaus, and I. Gruia
Technical University of Civil Engineering Bucharest, Faculty of Building Services, Bucharest, Romania
University of Bucharest, Faculty of Physics, Bucharest, Romania
A dynamic mathematical model, based on physical and transport properties and mass and energy balances, was developed for the simulation of unsteady convective drying of agricultural products (fruits and vegetables) in static bed conditions. The model utilizes water sorption isotherm equations and the change in solid density due to the shrinkage phenomenon. The aim of this article is to describe ...
Heat Transfer and Phase Transformation on Matrix Assisted Pulsed Laser Evaporation (MAPLE) of Biocompatible Thin Layers
E. Lacatus, G.C. Alecu, M.A. Sopronyi, A. Tudor
POLITEHNICA University of Bucharest, Bucharest, Romania
INFLPR -National Institute for Laser Plasma and Radiation Physics, Bucharest, Romania
Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique is used for the deposition of high quality biocompatible polymer thin films. During the deposition process the temperature of the laser target should be kept below 193K to assure the proper quality of both evaporation and deposition phases of the process. On a first approach COMSOL Multiphysics® was used to describe and analyze the ...
P. Pattnaik, S. K. Kamilla , Debi Prasad Das
MEMS Design Center, Institute of Technical Education & Research (ITER),Siksha ‘O’ Anushandhan University, Bhubaneswar-751030, Odisha,India
Process Engineering and Instrumentation Cell,Institute of Minerals and Materials Technology (IMMT),Bhubaneswar, Odisha,India
To prevent further complications in diabetes, proper management of blood glucose levels is essential. By using ultrasonic transceivers (both transmit and receive) the glucose level of human blood can be determined. By using this ultrasonic technique miniaturized sensors for non-invasive monitoring blood glucose levels. In this paper Barium Titanate (BT) thin film was used as a transmitter and ...
Simulation of Chemotractant Gradients in Microfluidic Channels to Study Cell Migration Mechanism in Silico
P. Wallin, E. Bernson, J. Gold
Chalmers University of Technology, Applied Physics, Biological Physics, Gothenburg, Sweden
Cell migration of endothelial cells along gradients is an important process in vivo and an interesting target for cancer therapeutics. Microfluidics offer very powerful tools to study such migration processes in detail in the lab. In this study, we describe a model to simulate molecular gradients in a diffusion based microfluidic gradient generator and how a cell senses these gradients via cell ...
A Practical Method to Model Complex Three-Dimensional Geometries with Non-Uniform Material Properties Using Image-based Design and COMSOL Multiphysics®
J. Cepeda, S. Birla, J. Subbiah, H. Thippareddi
Department of Food Science & Technology, University of Nebraska, Lincoln, NE, USA
Department of Biological Systems Engineering, University of Nebraska, Lincoln, NE, USA
Geometries with heterogeneous material properties are typically defined as a set of multiple parts, each part representing a different material. However, assembling or defining the individual parts of complex geometries can be difficult. A practical method based on image-based mesh generation, a custom algorithm for labeling materials, and interpolation functions of COMSOL Multiphysics® can be ...
J.G. Pieters, R. ElGamal, F. Ronsse
Faculty of Bioscience Engineering, Department of Biosystems Engineering, Ghent, Belgium
CFD simulations were carried out to predict the convective heat and mass transfer coefficients in the rice bed, and correlations were developed for the convective heat and mass transfer coefficients as a function of drying air flow rate. The developed correlations were used to extend the model developed by ElGamal et al. (2013) for thin-layer rice drying to volumetric heat and mass transfer in a ...
Acoustic Field Comparison of High Intensity Focused Ultrasound Using Experimental Characterization and Finite Element Simulation
J. L. Teja, A. Vera, L. Leija
Department of Electrical Engineering, Cinvestav-IPN, Mexico D.F., Mexico
High Intensity Focused Ultrasound (HIFU) is used as a noninvasive technique of tissue heating and ablation for different medical treatments. This paper presents a quantitative comparison of HIFU acoustic fields experimentally obtained versus simulated acoustic fields. Acoustic field characterization was realized in two HIFU transducers using water as a propagation medium. Also, simulations were ...