This document discusses axi-symmetric analysis and finite element modeling techniques for single-variable problems. It introduces axi-symmetric coordinates where quantities depend only on radial (r) and axial (z) coordinates, reducing a 3D problem to 2D. It presents the weak form, finite element model, and element stiffness matrix formulation for a single-variable problem. It also discusses constant strain triangle (CST) and isoparametric elements, where shape functions allow modeling of arbitrary geometries.
Chap-1 Preliminary Concepts and Linear Finite Elements.pptxSamirsinh Parmar
Linear Finite Elements, Vector and Tensor Calculus, Stress and Strain, FEA, Finite Element methods basics, Mechanics of Continuous bodies, Mechanics of Continuum, Continuum Mechanics, Preliminary concepts
constant strain triangular which is used in analysis of triangular in finite element method with the help of shape function and natural coordinate system.
1. The document discusses techniques for analyzing motion in video sequences, including optical flow estimation. Optical flow describes image motion vectors at each point.
2. Two main approaches to estimating optical flow are discussed: gradient-based methods using pixel intensity conservation, and feature point detection and matching between frames.
3. The Lucas-Kanade method is described, which assumes optical flow is locally constant and estimates it using a least squares approach on neighboring pixels.
1. The document describes the finite element formulation for 2D problems using constant strain triangles.
2. It involves dividing the body into finite elements connected at nodes, then approximating displacements within each element using shape functions of the nodes.
3. Strains and stresses are then approximated based on the displacements. This allows setting up the element stiffness matrix and load vector to solve for the unknown node displacements.
Mathematics (from Greek μάθημα máthēma, “knowledge, study, learning”) is the study of topics such as quantity (numbers), structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics
The document discusses techniques for clipping and rasterization in computer graphics. It covers line segment clipping algorithms like Cohen-Sutherland and Liang-Barsky. It also discusses polygon clipping, including brute force, triangulation, and a black box pipeline approach. Finally, it covers rasterization techniques for points, lines, and polygons, including inside-outside testing methods, fill algorithms like flood fill and scanline fill.
Digital control systems (dcs) lecture 18-19-20Ali Rind
This document discusses digital control systems and related topics such as difference equations, z-transforms, and mapping between the s-plane and z-plane. It begins with an outline of topics to be covered including difference equations, z-transforms, inverse z-transforms, and the relationship between the s-plane and z-plane. Examples are provided to illustrate difference equations, z-transforms, and mapping poles between the two planes. Standard z-transforms of discrete-time signals like the unit impulse and sampled step are also defined.
This document summarizes linear regression methods for modeling relationships between variables, including least squares regression, QR decomposition, subset selection, and coefficient shrinkage techniques. It introduces the linear regression model and describes how to estimate regression coefficients by minimizing the residual sum of squares. Methods for selecting significant variables like stepwise selection and for shrinking coefficients like ridge regression and the lasso are also overviewed. An example using prostate cancer data is presented to illustrate error comparison between models.
Chap-1 Preliminary Concepts and Linear Finite Elements.pptxSamirsinh Parmar
Linear Finite Elements, Vector and Tensor Calculus, Stress and Strain, FEA, Finite Element methods basics, Mechanics of Continuous bodies, Mechanics of Continuum, Continuum Mechanics, Preliminary concepts
constant strain triangular which is used in analysis of triangular in finite element method with the help of shape function and natural coordinate system.
1. The document discusses techniques for analyzing motion in video sequences, including optical flow estimation. Optical flow describes image motion vectors at each point.
2. Two main approaches to estimating optical flow are discussed: gradient-based methods using pixel intensity conservation, and feature point detection and matching between frames.
3. The Lucas-Kanade method is described, which assumes optical flow is locally constant and estimates it using a least squares approach on neighboring pixels.
1. The document describes the finite element formulation for 2D problems using constant strain triangles.
2. It involves dividing the body into finite elements connected at nodes, then approximating displacements within each element using shape functions of the nodes.
3. Strains and stresses are then approximated based on the displacements. This allows setting up the element stiffness matrix and load vector to solve for the unknown node displacements.
Mathematics (from Greek μάθημα máthēma, “knowledge, study, learning”) is the study of topics such as quantity (numbers), structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics
The document discusses techniques for clipping and rasterization in computer graphics. It covers line segment clipping algorithms like Cohen-Sutherland and Liang-Barsky. It also discusses polygon clipping, including brute force, triangulation, and a black box pipeline approach. Finally, it covers rasterization techniques for points, lines, and polygons, including inside-outside testing methods, fill algorithms like flood fill and scanline fill.
Digital control systems (dcs) lecture 18-19-20Ali Rind
This document discusses digital control systems and related topics such as difference equations, z-transforms, and mapping between the s-plane and z-plane. It begins with an outline of topics to be covered including difference equations, z-transforms, inverse z-transforms, and the relationship between the s-plane and z-plane. Examples are provided to illustrate difference equations, z-transforms, and mapping poles between the two planes. Standard z-transforms of discrete-time signals like the unit impulse and sampled step are also defined.
This document summarizes linear regression methods for modeling relationships between variables, including least squares regression, QR decomposition, subset selection, and coefficient shrinkage techniques. It introduces the linear regression model and describes how to estimate regression coefficients by minimizing the residual sum of squares. Methods for selecting significant variables like stepwise selection and for shrinking coefficients like ridge regression and the lasso are also overviewed. An example using prostate cancer data is presented to illustrate error comparison between models.
Random Matrix Theory and Machine Learning - Part 3Fabian Pedregosa
ICML 2021 tutorial on random matrix theory and machine learning.
Part 3 covers: 1. Motivation: Average-case versus worst-case in high dimensions 2. Algorithm halting times (runtimes) 3. Outlook
Convex Partitioning of a Polygon into Smaller Number of Pieces with Lowest Me...Kasun Ranga Wijeweera
The document describes an algorithm for convex partitioning of a polygon into the smallest number of convex pieces with the lowest memory consumption. The algorithm finds primary sectors by drawing line segments between reflex vertices, ensuring the segments do not intersect polygon edges or contain interior vertices. Secondary sectors are found by intersecting primary sectors. The algorithm runs in O(n3) time and O(n2) space, producing fewer convex pieces than prior algorithms with the same time complexity while using less memory. Key steps include representing the polygon, finding reflex vertices, testing intersections, and computing sector endpoints.
The document discusses various 2D geometric transformations including reflections, shears, and their matrix representations. It also covers 2D viewing pipelines including coordinate systems, clipping techniques like Cohen-Sutherland and Liang-Barsky line clipping, and Sutherland-Hodgeman polygon clipping. Reflections are described as 180 degree rotations about an axis. Shearing shifts points along an axis proportional to their coordinate on the other axis. Clipping algorithms discard or shorten line/polygon segments that fall outside the clip region.
This document provides information on various topics in math, science, and engineering. It begins with plane and solid geometry concepts like polygons, circles, triangles, and polyhedra. It then covers trigonometry, analytic geometry, calculus, differential equations, matrices and more. Example formulas are given for area, volume, sine, cosine, logarithms, and other calculations. Engineering concepts like vectors, friction, centroids, and moments of inertia are also summarized. The document contains a comprehensive review of formulas and principles across multiple STEM disciplines.
Conversion of transfer function to canonical state variable modelsJyoti Singh
Realization of transfer function into state variable models is needed even if the control system design based on frequency-domain design method.
In these cases the need arises for the purpose of transient response simulation.
But there is not much software for the numerical inversion of Laplace transform.
So one ways is to convert transfer function of the system to state variable description and numerically integrating the resulting differential equations rather than attempting to compute the inverse Laplace transform by numerical method.
This document discusses 3D graphics and transformations. It begins by introducing the goals of 3D graphics as producing 2D images from a mathematically described 3D environment. It then covers coordinate systems, affine transformations like translation, rotation, and scaling, and how they are represented by matrices. Homogeneous coordinates are introduced to represent transformations uniformly with matrices. Quaternions are also mentioned as an alternative to rotation matrices. The document provides examples of 3D translation, rotation, and issues around representing rotations.
The document describes several algorithms for drawing circles:
1. Using the circle equation requires significant computation and results in a poor appearance.
2. Using trigonometric functions is time-consuming due to trig computations.
3. The midpoint circle algorithm uses the midpoint between candidate pixels to determine which is closer to the actual circle. It has less computation than the circle equation.
4. Bresenham's circle algorithm uses a decision parameter D to iteratively select the next pixel, requiring fewer computations than trigonometric functions.
The document discusses various 2D and 3D transformations including translation, scaling, rotation, reflection, shearing, and homogeneous coordinates. It provides the mathematical definitions and matrix representations for each transformation type in 2D and 3D. It also covers topics like composition and inverse of transformations, classification of transformations, and properties of rigid body transformations.
Chap-2 Preliminary Concepts and Linear Finite Elements.pptxSamirsinh Parmar
non linear problem, linear finite element, formulate nonlinear problems, solve non linear problems, non linear structural problems, Linera vs Non Linear, Material Non linearity, Accuracy vs Convergence, Convergence Criteria
The document discusses various numerical techniques for solving equations and systems of equations. It covers bisection, regula falsi, Newton-Raphson, and interpolation methods for finding roots of equations. It also covers the Jacobi and Gauss-Seidel methods for solving systems of linear equations iteratively. Numerical differentiation and integration techniques like the trapezoidal, Simpson's, and Runge-Kutta methods are also summarized. Examples are provided to illustrate solving systems of equations using the Jacobi and Gauss-Seidel methods.
This document summarizes Ja-Keoung Koo's presentation on structure from motion. It discusses image formation, the structure from motion pipeline with calibrated cameras, and the 8-point algorithm. The key points are:
1. Image formation maps 3D world points to 2D image points using a camera's intrinsic and extrinsic parameters.
2. Structure from motion with calibrated cameras recovers 3D structure and camera motion from 2D correspondences using the essential matrix and 8-point algorithm.
3. The 8-point algorithm finds the essential matrix from point correspondences, decomposes it to recover the rotation and translation between views.
This document provides a summary of spatial data modeling and analysis techniques. It begins with an outline of the topics to be covered, including additive statistical models for spatial data, spatial covariance functions, the multivariate normal distribution, kriging for prediction and uncertainty, and the likelihood function for parameter estimation. It then introduces the key concepts and equations for modeling spatial processes as Gaussian random fields with specified covariance functions. Examples are given of commonly used covariance functions and the types of random surfaces they generate. Kriging is described as a best linear unbiased prediction technique that uses a spatial covariance function and observations to make predictions at unknown locations. The document concludes with examples of parameter estimation via maximum likelihood and using the fitted model to make predictions and conditional simulations
This document covers key topics in seismic data processing including complex numbers, vectors, matrices, determinants, eigenvalues, singular values, matrix inversion, series, Taylor series, Fourier series, delta functions, and Fourier integrals. It provides examples of using Taylor series to approximate nonlinear systems as linear systems and using Fourier series to approximate periodic functions. The importance of Fourier transforms for spectral analysis and various geophysical applications is also discussed.
Digital signatures are often used to implement electronic signatures, a broader term that refers to any electronic data that carries the intent of a signature, but not all electronic signatures use digital signatures. In some countries, including the United States, India, and members of the European Union, electronic signatures have legal significance.
Image mosaicing involves stitching together multiple overlapping images to create a panoramic mosaic. The key steps are: 1) Taking a sequence of images from the same position and computing the transformation between each image, 2) Warping the images to align them by shifting pixels according to the transformation, and 3) Blending the aligned images together, with techniques like weighted averaging, to produce a seamless mosaic. Key challenges include dealing with moving objects, illumination variations, and interpolating pixel values when pixels are mapped between discrete pixel locations during warping.
*Plain stress-strain,
*axi-symmetric problems in 2D elasticity
*Constant Strain Triangles (CST)- Element stiffness matrix, Assembling stiffness Equation, Load vector, stress and reaction forces calculations. (numerical treatment only on constant strain triangles)
*Post Processing Techniques- *Check and validate accuracy of results,
* Average and Un-average stresses,
*Special tricks for post processing,
*Interpretation of results and design modifications,
*CAE reports.
The document proposes an algorithm to find the largest circle that can fit inside an arbitrary polygon in O(k*n) time and O(n) space, where k is the number of random points generated inside the polygon's bounding rectangle and n is the number of vertices. The algorithm works by randomly generating points inside the polygon, finding the largest circle centered at each point, and selecting the largest among these circles. It determines if a random point is inside the polygon by counting edge intersections. The largest circle is the minimum of the distances to the closest vertex and edge. Repeating this process improves the approximation of the true largest circle.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
Random Matrix Theory and Machine Learning - Part 3Fabian Pedregosa
ICML 2021 tutorial on random matrix theory and machine learning.
Part 3 covers: 1. Motivation: Average-case versus worst-case in high dimensions 2. Algorithm halting times (runtimes) 3. Outlook
Convex Partitioning of a Polygon into Smaller Number of Pieces with Lowest Me...Kasun Ranga Wijeweera
The document describes an algorithm for convex partitioning of a polygon into the smallest number of convex pieces with the lowest memory consumption. The algorithm finds primary sectors by drawing line segments between reflex vertices, ensuring the segments do not intersect polygon edges or contain interior vertices. Secondary sectors are found by intersecting primary sectors. The algorithm runs in O(n3) time and O(n2) space, producing fewer convex pieces than prior algorithms with the same time complexity while using less memory. Key steps include representing the polygon, finding reflex vertices, testing intersections, and computing sector endpoints.
The document discusses various 2D geometric transformations including reflections, shears, and their matrix representations. It also covers 2D viewing pipelines including coordinate systems, clipping techniques like Cohen-Sutherland and Liang-Barsky line clipping, and Sutherland-Hodgeman polygon clipping. Reflections are described as 180 degree rotations about an axis. Shearing shifts points along an axis proportional to their coordinate on the other axis. Clipping algorithms discard or shorten line/polygon segments that fall outside the clip region.
This document provides information on various topics in math, science, and engineering. It begins with plane and solid geometry concepts like polygons, circles, triangles, and polyhedra. It then covers trigonometry, analytic geometry, calculus, differential equations, matrices and more. Example formulas are given for area, volume, sine, cosine, logarithms, and other calculations. Engineering concepts like vectors, friction, centroids, and moments of inertia are also summarized. The document contains a comprehensive review of formulas and principles across multiple STEM disciplines.
Conversion of transfer function to canonical state variable modelsJyoti Singh
Realization of transfer function into state variable models is needed even if the control system design based on frequency-domain design method.
In these cases the need arises for the purpose of transient response simulation.
But there is not much software for the numerical inversion of Laplace transform.
So one ways is to convert transfer function of the system to state variable description and numerically integrating the resulting differential equations rather than attempting to compute the inverse Laplace transform by numerical method.
This document discusses 3D graphics and transformations. It begins by introducing the goals of 3D graphics as producing 2D images from a mathematically described 3D environment. It then covers coordinate systems, affine transformations like translation, rotation, and scaling, and how they are represented by matrices. Homogeneous coordinates are introduced to represent transformations uniformly with matrices. Quaternions are also mentioned as an alternative to rotation matrices. The document provides examples of 3D translation, rotation, and issues around representing rotations.
The document describes several algorithms for drawing circles:
1. Using the circle equation requires significant computation and results in a poor appearance.
2. Using trigonometric functions is time-consuming due to trig computations.
3. The midpoint circle algorithm uses the midpoint between candidate pixels to determine which is closer to the actual circle. It has less computation than the circle equation.
4. Bresenham's circle algorithm uses a decision parameter D to iteratively select the next pixel, requiring fewer computations than trigonometric functions.
The document discusses various 2D and 3D transformations including translation, scaling, rotation, reflection, shearing, and homogeneous coordinates. It provides the mathematical definitions and matrix representations for each transformation type in 2D and 3D. It also covers topics like composition and inverse of transformations, classification of transformations, and properties of rigid body transformations.
Chap-2 Preliminary Concepts and Linear Finite Elements.pptxSamirsinh Parmar
non linear problem, linear finite element, formulate nonlinear problems, solve non linear problems, non linear structural problems, Linera vs Non Linear, Material Non linearity, Accuracy vs Convergence, Convergence Criteria
The document discusses various numerical techniques for solving equations and systems of equations. It covers bisection, regula falsi, Newton-Raphson, and interpolation methods for finding roots of equations. It also covers the Jacobi and Gauss-Seidel methods for solving systems of linear equations iteratively. Numerical differentiation and integration techniques like the trapezoidal, Simpson's, and Runge-Kutta methods are also summarized. Examples are provided to illustrate solving systems of equations using the Jacobi and Gauss-Seidel methods.
This document summarizes Ja-Keoung Koo's presentation on structure from motion. It discusses image formation, the structure from motion pipeline with calibrated cameras, and the 8-point algorithm. The key points are:
1. Image formation maps 3D world points to 2D image points using a camera's intrinsic and extrinsic parameters.
2. Structure from motion with calibrated cameras recovers 3D structure and camera motion from 2D correspondences using the essential matrix and 8-point algorithm.
3. The 8-point algorithm finds the essential matrix from point correspondences, decomposes it to recover the rotation and translation between views.
This document provides a summary of spatial data modeling and analysis techniques. It begins with an outline of the topics to be covered, including additive statistical models for spatial data, spatial covariance functions, the multivariate normal distribution, kriging for prediction and uncertainty, and the likelihood function for parameter estimation. It then introduces the key concepts and equations for modeling spatial processes as Gaussian random fields with specified covariance functions. Examples are given of commonly used covariance functions and the types of random surfaces they generate. Kriging is described as a best linear unbiased prediction technique that uses a spatial covariance function and observations to make predictions at unknown locations. The document concludes with examples of parameter estimation via maximum likelihood and using the fitted model to make predictions and conditional simulations
This document covers key topics in seismic data processing including complex numbers, vectors, matrices, determinants, eigenvalues, singular values, matrix inversion, series, Taylor series, Fourier series, delta functions, and Fourier integrals. It provides examples of using Taylor series to approximate nonlinear systems as linear systems and using Fourier series to approximate periodic functions. The importance of Fourier transforms for spectral analysis and various geophysical applications is also discussed.
Digital signatures are often used to implement electronic signatures, a broader term that refers to any electronic data that carries the intent of a signature, but not all electronic signatures use digital signatures. In some countries, including the United States, India, and members of the European Union, electronic signatures have legal significance.
Image mosaicing involves stitching together multiple overlapping images to create a panoramic mosaic. The key steps are: 1) Taking a sequence of images from the same position and computing the transformation between each image, 2) Warping the images to align them by shifting pixels according to the transformation, and 3) Blending the aligned images together, with techniques like weighted averaging, to produce a seamless mosaic. Key challenges include dealing with moving objects, illumination variations, and interpolating pixel values when pixels are mapped between discrete pixel locations during warping.
*Plain stress-strain,
*axi-symmetric problems in 2D elasticity
*Constant Strain Triangles (CST)- Element stiffness matrix, Assembling stiffness Equation, Load vector, stress and reaction forces calculations. (numerical treatment only on constant strain triangles)
*Post Processing Techniques- *Check and validate accuracy of results,
* Average and Un-average stresses,
*Special tricks for post processing,
*Interpretation of results and design modifications,
*CAE reports.
The document proposes an algorithm to find the largest circle that can fit inside an arbitrary polygon in O(k*n) time and O(n) space, where k is the number of random points generated inside the polygon's bounding rectangle and n is the number of vertices. The algorithm works by randomly generating points inside the polygon, finding the largest circle centered at each point, and selecting the largest among these circles. It determines if a random point is inside the polygon by counting edge intersections. The largest circle is the minimum of the distances to the closest vertex and edge. Repeating this process improves the approximation of the true largest circle.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
5. FiniteElement Model – Single-VariableProblem
u u jj
j
Ritzmethod:
e
n
e e
K u f Qe
ij j i i
j1
where j (r, z) j (x, y)
w i
Weakform
22
138
e
j j
a
i i
K e
a a
rdrdz
00 i j
r r z z
ij 11
where
i i
e
f e
frdrdz
i i n
e
Qe
q ds
7. 3-Node Axi-symmetricElement
T (r, z) T11 T22 T33
1
2
3
140
1 2 3
e
1 r z
2A
r2z3 r3z2
z z
r r
3 2
3 1 1 3
2 3 1
e
1 r z
2A
r z r z
z
z
r r
1 3
1 2 2 1
3 1 2
e
1 r z
2A
r z r z
z z
r r
2 1
8. 4-Node Axi-symmetricElement
T (r, z) T11 T22 T33 T44
1 2
3
4
a
b
r
141
z
2
3
a b
1
1
1
1
a b a b
1
4 a b
9. Single-Variable Problem –Example
Step1: Discretization
Step2: Element equation
e
142
j
i
ij
K e
i
j
rdrdz
r r z z
i i
e
f e
frdrdz
i i n
e
Qe
q ds
10. Reviewof CSTElement
• Constant Strain Triangle (CST)- easiest and simplest
finite element
– Displacement field in terms ofgeneralized coordinates
– Resulting strain field is
– Strains do not vary within the element. Hence, the name
constant strain triangle(CST)
• Other elements are not solucky.
• Canalso be called linear triangle becausedisplacement field is
linear in xand y - sidesremainstraight.
143
11. Constant Strain Triangle
• Thestrain field from the shapefunctions lookslike:
– Where, xi and yi are nodal coordinates (i=1, 2,3)
– xij =xi - xj and yij=yi - yj
– 2Ais twice the area of the triangle, 2A=x21y31-x31y21
• Node numbering is arbitrary except that the sequence123
must go clockwise around the element if Ais tobe positive.
144
12. 145
Constant Strain Triangle
• Stiffness matrix for element k =BTEBtA
• TheCSTgivesgood results in regions of theFE
model where there is little straingradient
– Otherwise it does notwork well.
13. Linear Strain Triangle
• Changesthe shape functions and results in
quadratic displacement distributions and
linear strain distributions within theelement.
146
21. 154
Quadratic Quadrilateral Element
• Should we try to use this element to solve our
problem?
• Or try fixing the Q4element for our purposes.
– Hmm…toughchoice.
22. 155
Isoparametric Elements and Solution
• Biggestbreakthrough in the implementation of the
finite element method is the development of an
isoparametric element with capabilities to model
structure (problem) geometries of any shapeandsize.
• Thewhole idea works onmapping.
– Theelement in the real structure is mapped to an
‘imaginary’ element in an ideal coordinatesystem
– Thesolution to the stress analysis problem is easyand
known for the ‘imaginary’element
– Thesesolutions are mapped back to the element inthe
real structure.
– All the loads and boundary conditions are also mapped
from the real to the ‘imaginary’ element in this approach
24. Isoparametric element
Y
1 2 3 4
0 0 0 N1
X N
0
• The mappingfunctions areq
x1u
ite simple:
4
x
2
x3
N N N 0 0 0 0 x
N2 N3 N4 y1
y2
1
4
N 1 (1)(1)
2
4
N
1
(1 )(1)
3
4
N 1 (1 )(1 )
4
4
N
1
(1)(1 )
y3
y4
Basically, thex and y coordinatesof any point in the
elementare interpolations of the nodal (corner)
coordinates.
Fromthe Q4 element,thebilinear shape functions
are borrowed to be used as the interpolation
functions. They readily satisfy the boundaryvalues
too. 157
25. Isoparametric element
v
1 2 3 4
0 0 0 N1
u N
0
• Nodal shape functions for d
u
i1s
placements
4
u
2
u3
N N N 0 0 0 0 u
N2 N3 N4 v1
v2
v3
v4
1
4
N 1 (1)(1)
2
4
N
1
(1 )(1)
3
4
N 1 (1 )(1 )
4
4
N
1
(1)(1 ) 158
27. Isoparametric Element
X Y
u
u
X Y u
X Y u
X
Y
It is easier to obtain
X
and
Y
X Y
J X Y Jacobian
defines coordinate transformation
Hencewe will do itanother way
u
u
X
u
Y
X Y
u
u
X
u
Y
X
Ni
X
i
Y N
i
Yi
X N
i X i
Y N
i Yi
X
u
Y
u
1
u
J
u
169
28. 161
GaussQuadrature
• Themapping approach requires usto be able to
evaluate the integrations within the domain (-1…1)of
the functionsshown.
• Integration canbe done analytically by usingclosed-
form formulas from atable ofintegrals (Nah..)
– Or numerical integration can be performed
• Gaussquadrature is the more common form of
numerical integration - better suited for numerical
analysis and finite elementmethod.
• Itevaluated the integral of afunction asasum of a
becomes
n
I Wii
i1
finite numb1er of terms
I d
1
30. Numerical Integration
Calculate:
b
I f xdx
a
• Newton – Cotesintegration
• Trapezoidalrule – 1storderNewton-Cotesintegration
• Trapezoidalrule – multipleapplication
1
b a
f (x) f (x) f (a)
f (b) f (a)
(x a)
2
f (a) f (b)
b b
I f (x)dx f1(x)dx (b a)
a a
b
163
xn1
xn x1 x2 xn
a x0 x0 x1
I f (x)dx fn (x)dx f (x)dx f (x)dx f
(x)dx
2
n1
i1
i
f (x ) f (b)
f (a) 2
h
I
31. Numerical Integration
Calculate:
b
I f xdx
a
• Newton – Cotesintegration
• Simpson1/3 rule – 2ndorderNewton-Cotesintegration
2
2
0 1
1
0 2
0 1
2 f (x )
(x2 x0 )(x2 x1)
(x x0 )(x x1)
f (x ) f (x )
(x0 x1)(x0 x2 ) (x x )(x x )
(x x1)(x x2 ) (x x )(x x )
f (x) f (x)
b b
a a
6
f (x ) 4 f (x ) f (x )
I f (x)dx f2 (x)dx (x2 x0 ) 0 1 2
164
32. Numerical Integration
Calculate:
b
I f xdx
2
(b a)
f (a)
(b a)
f(b)
2 2
165
I (b a)
f (a) f (b)
I c0 f (x0 ) c1 f (x1)
a
• GaussianQuadrature
Trapezoidal Rule: GaussianQuadrature:
Choose according to certaincriteria
c0,c1,x0 , x1
33. Numerical Integration
Calculate:
b
I f xdx
a
• GaussianQuadrature
3
1
1
1
1
I f xdx f
3
f
1
• 3pt GaussianQuadrature
I f xdx 0.55 f 0.77 0.89 f 0 0.55 f0.77
1
1
1
• 2pt GaussianQuadrature
I f xdx c0 f x0 c1 f x1 cn1 f xn1
b a
~
x 1
2(x a)
Let:
b 1
1
a
166
~ ~
1 1 1
f (x)dx
2
(b a) f 2
(a b)
2
(b a)xdx