Estimation of skin impedance models with experimental data and a proposed model for human skin impedance

The contact deformation of human skin is a significant factor in the virtual ergonomic assessment of handheld products, but previous works have neglected it or dealt with it in a simple way. In this paper, we propose a physical model of the contact deformation of human skin and, based on this model, present an efficient contact solving method to simulate the physical contact of the Digital Hand with product surfaces. The realistic contact deformation effect was realized, and we experimentally verified the estimated contact area, contact force and pressure distribution, and found the estimation results by the proposed model and the contact solving method well fit with the experimental data and the past data from the literature.

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Dual Release Model to Evaluate Dissolution Profiles from Swellable Drug Polyelectrolyte Matrices

Current Drug Delivery ◽

10.2174/1567201817666200512093115 ◽

2020 ◽

Vol 17 (6) ◽

pp. 511-522 ◽

Cited By ~ 2

Author(s):

Alicia Graciela Cid ◽

María Verónica Ramírez-Rigo ◽

María Celeste Palena ◽

Elio Emilio Gonzo ◽

Alvaro Federico Jimenez-Kairuz ◽

...

Keyword(s):

Experimental Data ◽

Drug Release ◽

Inflection Point ◽

Release Profile ◽

Experimental Point ◽

Extended Model ◽

Release Process ◽

Proposed Model ◽

Dual Release ◽

Release Model

Background: Mathematical modeling in modified drug release is an important tool that allows predicting the release rate of drugs in their surrounding environment and elucidates the transport mechanisms involved in the process. Objective: The aim of this work was to develop a mathematical model that allows evaluating the release profile of drugs from polymeric carriers in which the swelling phenomenon is present. Methods: Swellable matrices based on ionic complexes of alginic acid or carboxymethylcellulose with ciprofloxacin were prepared and the effect of adding the polymer sodium salt on the swelling process and the drug release was evaluated. Experimental data from the ciprofloxacin release profiles were mathematically adjusted, considering the mechanisms involved in each stage of the release process. Results: A proposed model, named “Dual Release” model, was able to properly fit the experimental data of matrices presenting the swelling phenomenon, characterized by an inflection point in their release profile. This entails applying the extended model of Korsmeyer-Peppas to estimate the percentage of drug released from the first experimental point up to the inflection point and then a model called Lumped until the final time, allowing to adequately represent the complete range of the drug release profile. Different parameters of pharmaceutical relevance were calculated using the proposed model to compare the profiles of the studied matrices. Conclusion: The “Dual Release” model proposed in this article can be used to predict the behavior of complex systems in which different mechanisms are involved in the release process.

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Wear of a Tool in Double-Disk Lapping of Silicon Wafers

ASME 2010 International Manufacturing Science and Engineering Conference, Volume 1 ◽

10.1115/msec2010-34323 ◽

2010 ◽

Cited By ~ 3

Author(s):

Adam Barylski ◽

Mariusz Deja

Keyword(s):

Experimental Data ◽

Integrated Circuits ◽

Tool Wear ◽

Silicon Wafers ◽

Silicon Ingot ◽

Proposed Model ◽

Tool Wear Prediction ◽

Simulation Results ◽

High Degree ◽

Kinematical Parameters

Silicon wafers are the most widely used substrates for fabricating integrated circuits. A sequence of processes is needed to turn a silicon ingot into silicon wafers. One of the processes is flattening by lapping or by grinding to achieve a high degree of flatness and parallelism of the wafer [1, 2, 3]. Lapping can effectively remove or reduce the waviness induced by preceding operations [2, 4]. The main aim of this paper is to compare the simulation results with lapping experimental data obtained from the Polish producer of silicon wafers, the company Cemat Silicon from Warsaw (www.cematsil.com). Proposed model is going to be implemented by this company for the tool wear prediction. Proposed model can be applied for lapping or grinding with single or double-disc lapping kinematics [5, 6, 7]. Geometrical and kinematical relations with the simulations are presented in the work. Generated results for given workpiece diameter and for different kinematical parameters are studied using models programmed in the Matlab environment.

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Effect of Interaction Modeling in AFM-Based Nanomanipulation

ASME 2008 Dynamic Systems and Control Conference, Parts A and B ◽

10.1115/dscc2008-2153 ◽

2008 ◽

Author(s):

Fakhreddine Landolsi ◽

Fathi H. Ghorbel ◽

James B. Dabney

Keyword(s):

Experimental Data ◽

Numerical Simulations ◽

Interaction Model ◽

Collision Process ◽

Visual Sensing ◽

Proposed Model ◽

Interaction Modeling

AFM-based nanomanipulation is very challenging because of the complex mechanics in tip-sample interactions and the limitations in AFM visual sensing capabilities. In the present paper, we investigate the modeling of AFM-based nanomanipulation emphasizing the effects of the relevant interactions at the nanoscale. The major contribution of the present work is the use of a combined DMT-JKR interaction model in order to describe the complete collision process between the AFM tip and the sample. The coupling between the interactions and the friction at the nanoscale is emphasized. The efficacy of the proposed model to reproduce experimental data is demonstrated via numerical simulations.

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Analytical Model for Restraint Strains and Self-stressed in Expansive Concrete Filled Steel Tubes (ECFST) estimation

10.36773/1818-1212-2020-119-1-93-98 ◽

2020 ◽

pp. 93-98

Author(s):

Viktar V. Tur ◽

Radoslaw Duda ◽

Dina Khmaruk ◽

Viktar Basav

Keyword(s):

Experimental Data ◽

Experimental Studies ◽

Steel Tube ◽

Development Model ◽

Steel Tubes ◽

Concrete Core ◽

Expansive Concrete ◽

Proposed Model ◽

Comparison Results ◽

Concrete Filled Steel Tubes

In this paper, a modified strains development model (MSDM) for expansive concrete-filled steel tube (ECFST) was formulated and verified on the experimental data, obtained from testing specimens on the expansion stage. The modified strain development model for restraint strains and self-stresses values estimation in concrete with high expansion energy capacity under any type of the symmetrical and unsymmetrical finite stiffness restraint conditions was proposed. Based on proposed MSDM a new model for expansive concrete-filled steel tubes is developed. The main difference between this model and other previously developed models consists in taking into account in the basic equations an induced force in restrain that is considered as an external load applied to the concrete core of the member. For verification of the proposed model-specific experimental studies were performed. As follows from comparison results restrained expansion strains values calculated following the proposed model shows good compliance with experimental data. The values predicted by the proposed MSDM for concrete-filled steel and obtained experimental data demonstrated good agreement that confirms the validity of the former.

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Study of Donor Centres in n-InSb due to the Temperature Annealing

Materials Science Forum ◽

10.4028/www.scientific.net/msf.480-481.197 ◽

2005 ◽

Vol 480-481 ◽

pp. 197-200

Author(s):

Y. Sayad ◽

A. Nouiri

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Annealing Time ◽

Annealing Temperature ◽

Theoretical Study ◽

Donor Concentration ◽

Model Based ◽

Proposed Model ◽

Kinetics Of ◽

Best Fit

An increasing of donor centres has been detected in n-InSb when it was submitted to anneal/quench with various annealing temperature (450 °C - 850 °C) and various annealing time (5 - 100 hours). A theoretical study of the kinetics of the conduction conversion of n-InSb at temperature annealing above 250 °C has been made. The present analysis indicates that the donor concentration increases with increasing of annealing time. In order to study this variation and to give a model for donor centres generated, a proposed model based on the simple kinetic is used to fit the variation of donor concentration as a function of annealing time. However, from the best fit of experimental data using the proposed model, the activation energy is determined.

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Modelling of the behaviour of metal foams under shock compression

EPJ Web of Conferences ◽

10.1051/epjconf/201818301041 ◽

2018 ◽

Vol 183 ◽

pp. 01041

Author(s):

Nicolas Jacques ◽

Romain Barthélémy

Keyword(s):

Experimental Data ◽

Excellent Agreement ◽

Strain Curve ◽

Metal Foams ◽

Cellular Materials ◽

Theoretical Modelling ◽

Stress Strain Curve ◽

Open Cell ◽

Proposed Model ◽

Shock Response

A theoretical modelling is proposed to describe the shock response of foam materials. This model is based on micromechanical and energetic arguments, and takes into account the contribution of microscale inertia. Within this framework, an analytical expression of the Hugoniot stress-strain curve is proposed for elastic-plastic cellular materials. The predictions derived from the proposed model are in excellent agreement with experimental data for open-cell aluminium foams. The case of viscoplastic foams is also considered.

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Study of the Impact of PV-Thermal and Nanofluids on the Desalination Process by Flashing

Applied System Innovation ◽

10.3390/asi3010010 ◽

2020 ◽

Vol 3 (1) ◽

pp. 10

Author(s):

Samuel Sami

Keyword(s):

Experimental Data ◽

Numerical Modeling ◽

Solar System ◽

Solar Radiation ◽

Base Fluid ◽

Control Volume ◽

Proposed Model ◽

Finite Control ◽

The Impact ◽

Mathematical And Numerical Modeling

In this study, a mathematical and numerical modeling of the photovoltaic (PV)-thermal solar system to power the multistage flashing chamber process is presented. The proposed model was established after the mass and energy conservation equations written for finite control volume were integrated with properties of the water and nanofluids. The nanofluids studied and presented herein are Ai2O3, CuO, Fe3O4, and SiO2. The multiple flashing chamber process was studied under various conditions, including different solar radiation levels, brine flows and concentrations, and nanofluid concentrations as well as flashing chamber temperatures and pressures. Solar radiation levels were taken as 500 w/m2, 750 w/m2, 1000 w/m2, and finally, 1200 w/m2. The nanofluid volumetric concentrations considered varied from 1% to 20%. There is clear evidence that the higher the solar radiation, the higher the flashed flow produced. The results also clearly show that irreversibility is reduced by using nanofluid Ai2O3 at higher concentrations of 10% to 20% compared to water as base fluid. The highest irreversibility was experienced when water was used as base fluid and the lowest irreversibility was associated with nanofluid SiO2. The irreversibility increase depends upon the type of nanofluid and its thermodynamic properties. Furthermore, the higher the concentration (e.g., from 10% to 20% of Ai2O3), the higher the availability at the last flashing chamber. However, the availability is progressively reduced at the last flashing chamber. Finally, the predicted results compare well with experimental data published in the literature.

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Modelling the Characteristics of Ring-Shaped Magnetoelastic Force Sensor in Mohri’s Configuration

Sensors ◽

10.3390/s20010266 ◽

2020 ◽

Vol 20 (1) ◽

pp. 266 ◽

Cited By ~ 2

Author(s):

Anna Ostaszewska-Liżewska ◽

Roman Szewczyk ◽

Peter Raback ◽

Mika Malinen

Keyword(s):

Experimental Data ◽

High Sensitivity ◽

Force Sensor ◽

Inhomogeneous Distribution ◽

The Finite Element Method ◽

The Core ◽

Magnetoelastic Effect ◽

Proposed Model ◽

Distribution Of Stresses ◽

Good Agreement

Magnetoelastic force sensors exhibit high sensitivity and robustness. One commonly used configuration of force sensor with a ring-shaped core was presented by Mohri at al. In this configuration force is applied in the direction of a diameter of the core. However, due to inhomogeneous distribution of stresses, model of such sensor has not been presented yet. This paper is filling the gap presenting a new method of modelling the magnetoelastic effect, which is especially suitable for the finite element method. The presented implementation of proposed model is in good agreement with experimental data and creates new possibilities of modelling other devices utilizing magnetoelastic effect.

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