A Three Dimensional Virtual System Used to Analyze the Normal and Prosthetic Joint of the Hip

2019 ◽  
Vol 34 ◽  
pp. 165-174
Author(s):  
Razvan Cristian Vaduva ◽  
Ilaria Lorena Petrovici ◽  
Mihai Catalin Tenovici ◽  
Danut Nicolae Tarnita ◽  
Dragoş Laurenţiu Popa ◽  
...  
Keyword(s):  
Femoral Neck ◽  
Surgical Procedures ◽  
Hip Arthroplasty ◽  
Three Dimensional ◽  
Prosthetic Material ◽  
Joint Movement ◽  
Prosthetic Joint ◽  
Cemented Arthroplasty ◽  
Three Dimensional Models ◽  
Materials Used

Treatment of hip pathology has evolved over the last two centuries, ranging from rudimentary surgical procedures to modern hip arthroplasty, with an explosion marked in the last 30 years, considered to be one of the most successful surgeries to date. Hip arthroplasty is a permanent challenge due to the desire to discover the "supreme prosthesis", for which competition is still open. Hip disorders requiring prosthesis show a change in articular morphology. Among the most common medical conditions that have as final therapeutic solution hip arthroplasty are: coxarthrosis, both primary and secondary, followed by traumatic conditions: femoral neck collapse and femoral neck pseudarthrosis, aseptic head necrosis femoral stage III, as well as rheumatic coxitis from rheumatoid arthritis, ankylosing spondylitis or juvenile art. Endoprosthetic arthroplasty can be defined as an intervention of reconstructive surgery with bone sacrifice and prosthetic replacement of the articular components. It is, in the end, an operation aimed at restoring joint mobility and normal functioning of the muscles, ligaments and other periarticular structures that control joint movement. The materials initially used (glass, metal, plastic) did not have the desired bone strength and integration capacity. It followed the development of cemented implants, obtaining different types of cement with better and better quality. Problems arising from cemented arthroplasty (decimation, involving prosthetic revision) have led to a parallel development of the design and materials used for uncured prostheses with the possibility of very good integration of prosthetic material into the bone, raising them to the top of preferences in recent years. Treatment of hip pathology has evolved over the last two centuries, ranging from rudimentary surgical procedures to modern hip arthroplasty, with an explosion marked in the last 30 years, considered to be one of the most successful surgeries to date. The purpose of this study was to obtain the three-dimensional models of the hip joint and the prosthesis for the use of these models for various analyzes and virtual experiments. At the end of the paper important conclusions were drawn based on the results obtained in the simulations using the finite element method.

scholarly journals Three-dimensional models in planning of revision hip arthroplasty with complex acetabular defects

2018 ◽  
Vol 52 (6) ◽  
pp. 625 ◽  
Author(s):  
YaroslavA Rukin ◽  
GennadiyM Kavalerskiy ◽  
ValeriyY Murylev ◽  
PavelM Elizarov ◽  
AlexeyV Lychagin ◽  
...  
Keyword(s):  
Hip Arthroplasty ◽  
Three Dimensional ◽  
Revision Hip Arthroplasty ◽  
Dimensional Models ◽  
Three Dimensional Models ◽  
Acetabular Defects

scholarly journals Analysis of the dependence of stresses and deformations on the surfaces of shoe soles of different thicknesses and materials

2021 ◽  
Vol 273 ◽  
pp. 05001
Author(s):  
Olesya Golubeva ◽  
Alina Pogorelova
Keyword(s):  
Three Dimensional ◽  
Stress And Strain ◽  
Medium Density ◽  
Suitable Material ◽  
Two Component ◽  
Shoe Soles ◽  
Three Dimensional Models ◽  
Materials Used ◽  
Distribution Of Stress ◽  
Shape And Size

For this study, three-dimensional models of the soles of work shoes of different thicknesses and consisting of different materials were created. These models were analyzed to obtain the distribution of stress and strain on their surfaces. To build the model, we used experimental data on the shape and size of the sole, as well as the properties of specific materials used in the manufacture of soles for work shoes used in agriculture. The goal was to determine the most suitable material, that is, which of the materials has the most suitable characteristics for the sole, has the best wear resistance when used in agriculture. We noticed a significant reduction in deformations on the surface of the sole with an increase in the thickness of the sole, as well as when using two-component casting of the sole from a combination of materials: low-density EVA and flexible PU, medium-density EVA and soft PVC. This indicates their advantages and maximum suitability.

scholarly journals Simulation Models for Solar Photovoltaic Materials

2021 ◽  
pp. 114-133
Author(s):  
M. Rizwan
Keyword(s):  
Solar Cell ◽  
Band Structure ◽  
Computer Modelling ◽  
Three Dimensional ◽  
Simulation Models ◽  
Semiconductor Materials ◽  
Long Time ◽  
Three Dimensional Models ◽  
Materials Used ◽  
Device Operation

Semiconducting materials have dominated the photovoltaic industry for a long time. The advancement in solar cell technology is significantly influenced by computer modelling, designing and simulations of the semiconductor materials used for the device operation. Different modelling techniques including one, two and three dimensional models had been employed to comprehend the device operation of solar cell and other electronic devices based on semiconductor materials such as silicon and gallium arsenide. The performance of computing power is increasing with the passage of time in order to improve modelling and designing of different semiconductor materials for solar cell devices. In this chapter, different reported semiconductor materials, their standard characteristics and basic history of modelling, standard models used in photovoltaic industry and principles of modelling such as carrier statistics, transitions, band structure and mobility are explained in detail. Different characteristics of semiconductor material like the carrier transportation, carrier statistics, band structure, and heavy doping effect and carrier generations are described with respect to material modelling.

Characterization of Hygroscopic Swelling and Thermo-Hygro-Mechanical Design on Electronic Package

2009 ◽  
Vol 25 (3) ◽  
pp. 225-232 ◽  
Author(s):  
H.-C. Hsu ◽  
Y.-T. Hsu
Keyword(s):  
Moisture Absorption ◽  
Mechanical Design ◽  
Three Dimensional ◽  
Polymeric Materials ◽  
Moisture Diffusivity ◽  
Moisture Concentration ◽  
Moisture Expansion ◽  
Hygroscopic Swelling ◽  
Three Dimensional Models ◽  
Materials Used

AbstractThis paper discusses a successful experimental procedure to determine the hygroscopic swelling property of polymeric materials used in electronic packaging. Saturated moisture concentration and moisture diffusivity were determined by measuring the weight gain during moisture absorption. Hygromechanical properties, such as the coefficientof moisture expansion (CME), were determined through Thermo-Mechanical Analyzer (TMA) and Thermo-Gravimetric Analyzer (TGA) techniques. Fick's law of transient diffusion is solved by using finite element (FE) analysis to evaluate the overall moisture distributions. Both two-dimensional and three-dimensional models based on the FE software ANSYS were developed to predict the thermal-induced strain, hygroscopic swelling deformation, and residual thermohygro-mechanicalstress distributions. Reliability analysis at three JEDEC preconditioning standards 60°C60%RH, 85°C60%RH and 85°C85%RH was carried out. A series of comprehensive parametric studies were conducted in this research.

Plastic replicas as three-dimensional models of pulps

1975 ◽  
Vol 39 (8) ◽  
pp. 544-546
Author(s):  
HL Wakkerman ◽  
GS The ◽  
AJ Spanauf
Keyword(s):  
Three Dimensional ◽  
Dimensional Models ◽  
Three Dimensional Models

HYDROXYAPATITE, ALGINATE, AND CHITOSAN FOR BONE SCAFFOLDS: SPECTROSCOPY STUDY

2016 ◽  
Vol 19 (2) ◽  
pp. 93-100
Author(s):  
Lalita El Milla
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Functional Groups ◽  
Bone Growth ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Tissue Engineering Scaffolds ◽  
Hydroxyapatite Powder ◽  
Materials Used

Scaffolds is three dimensional structure that serves as a framework for bone growth. Natural materials are often used in synthesis of bone tissue engineering scaffolds with respect to compliance with the content of the human body. Among the materials used to make scafffold was hydroxyapatite, alginate and chitosan. Hydroxyapatite powder obtained by mixing phosphoric acid and calcium hydroxide, alginate powders extracted from brown algae and chitosan powder acetylated from crab. The purpose of this study was to examine the functional groups of hydroxyapatite, alginate and chitosan. The method used in this study was laboratory experimental using Fourier Transform Infrared (FTIR) spectroscopy for hydroxyapatite, alginate and chitosan powders. The results indicated the presence of functional groups PO43-, O-H and CO32- in hydroxyapatite. In alginate there were O-H, C=O, COOH and C-O-C functional groups, whereas in chitosan there were O-H, N-H, C=O, C-N, and C-O-C. It was concluded that the third material containing functional groups as found in humans that correspond to the scaffolds material in bone tissue engineering.

Validation of a Belt Model for Prediction of Hub Forces from a Rolling Tire4

2009 ◽  
Vol 37 (2) ◽  
pp. 62-102 ◽  
Author(s):  
C. Lecomte ◽  
W. R. Graham ◽  
D. J. O’Boy
Keyword(s):  
Internal Pressure ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
Prediction Method ◽  
Analytical Models ◽  
Beam Model ◽  
Impedance Boundary ◽  
Bending Waves ◽  
Tire Rotation ◽  
Three Dimensional Models

Abstract An integrated model is under development which will be able to predict the interior noise due to the vibrations of a rolling tire structurally transmitted to the hub of a vehicle. Here, the tire belt model used as part of this prediction method is first briefly presented and discussed, and it is then compared to other models available in the literature. This component will be linked to the tread blocks through normal and tangential forces and to the sidewalls through impedance boundary conditions. The tire belt is modeled as an orthotropic cylindrical ring of negligible thickness with rotational effects, internal pressure, and prestresses included. The associated equations of motion are derived by a variational approach and are investigated for both unforced and forced motions. The model supports extensional and bending waves, which are believed to be the important features to correctly predict the hub forces in the midfrequency (50–500 Hz) range of interest. The predicted waves and forced responses of a benchmark structure are compared to the predictions of several alternative analytical models: two three dimensional models that can support multiple isotropic layers, one of these models include curvature and the other one is flat; a one-dimensional beam model which does not consider axial variations; and several shell models. Finally, the effects of internal pressure, prestress, curvature, and tire rotation on free waves are discussed.

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