A the HEAVISIDE and DIRAC Functions If We Use the HEAVISIDE Function H(T − A) Defined in (A.1)

Total Page:16

File Type:pdf, Size:1020Kb

A the HEAVISIDE and DIRAC Functions If We Use the HEAVISIDE Function H(T − A) Defined in (A.1) ATheHEAVISIDE and DIRAC Functions The HEAVISIDE unit function , also called the unit step function, is defined according to ⎧ ⎨⎪ 1 for t>a, ≥ − 1 for t a, − 1 H(t a):= or H(t a): 2 for t = a, (A.1a,b) 0 for t<a, ⎩⎪ 0 for t<a, where t is the time variable and t = a denotes a time at which a step change has been occured (Fig.A.1). H(t-a) H(t-a) 1 1 1 2 0 a t 0 a t Fig. A.1 HEAVISIDE functions (A.1a,b) A step change in shear stress from τ =0to τ = τ0 at t = a may be expressed by τ(t)=τ0H(t − a) . (A.2) Another step function is shown in Fig. 11.1, which can be represented as follows σ(t)=σ0H(t)+Δσ1H(t − Θ1)+Δσ2H(t − Θ2)+... (A.3a) n σ(t)=σ0H(t)+ ΔσiH(t − Θi) , (A.3b) i=1 286 A The HEAVISIDE and DIRAC Functions if we use the HEAVISIDE function H(t − a) defined in (A.1). Similarly to (A.3) and Fig.11.1 the step function h(t)=H(t − a)+2H(t − 2a)+3H(t − 4a) (A.4) is drawn in Fig. A.2. 6 h(t) 3 1 0 a 2a 4a t Fig. A.2 Several steps Adding and subtracting unit step functions at times t equal to a, 2a, 3a, ... we arrive at the square wave N h(t)=H(t)+2 (−1)nH(t − na) (A.5) n=1 illustrated in Fig. A.3. 1 0 a 2a 3a 4a 5a t -1 Fig. A.3 Square wave (A.5) ATheHEAVISIDE and DIRAC Functions 287 The unit step function (A.1) is defined in MAPLE under the name Heavi- side. For example, the influence of the HEAVISIDE function on sin(t) and cos2(t) is illustrated in Fig. A.4a. A 1.mws > alias(H=Heaviside,th=thickness): > plot1:=plot(H(t-1),t=0..Pi,th=3): > plot2:=plot(sin(t)*H(t-1), t=0..Pi, th=3): > plot3:=plot((cos(t))ˆ2*H(t-1), > t=0..Pi,th=3): > plots[display]({plot1,plot2,plot3}); 1 H(t−1) 0.8 H(t−1)sin(t) 0.6 0.4 H(t−1)cos2 (t) 0.2 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 t t 2 Fig. A.4a Influence of the HEAVISIDE function on sin(t) and cos (t) Another example is illustrated in Fig. A.4b, where the vertical lines have been produced by HEAVISIDE functions. A 2.mws > alias(H=Heaviside,th=thickness): > plot1:=plot({-1,1,2,3,4,5}, X=0..5,-1..5, > scaling=constrained, color=black,th=2): > plot2:=plot({5*H(x-1)+5*H(x-1.001), > -H(x-1)-H(x-1.001), 5*H(x-2)+5*H(x-2.001), > 2+H(x-3.5)+3*H(x-3.501),5*H(x-5)+ > 5*H(x-5),-H(x-5)-H(x-5.001)}, > x=0..5.00001, -1..5, color=black, th=3): > plots[display]({plot1,plot2}); 288 A The HEAVISIDE and DIRAC Functions 5 4 3 2 1 0 12345 –1 Fig. A.4b Vertical lines generated by HEAVISIDE functions In some Figures, for instance in Fig. B.1, HEAVISIDE functions have been used in order to generate vertical lines. Besides the HEAVISIDE unit function (A.1) the DIRAC delta function, also called the unit impulse function, plays a central role in creep mechanics, for instance in (11.11b), and is defined according to 0 for t = a, δ(t − a):= (A.6) ∞ for t = a. This function has the properties &∞ δ(t − a)dt =1 (A.7) 0 and ATheHEAVISIDE and DIRAC Functions 289 &∞ δ(t − a) f(t)dt = f(a) (A.8) 0 for every continuous function f(t) and also valid for a =0. The property (A.7) of the delta function can geometrically interpreted as illustrated in Fig. A.5. @A(t - a) 1 A 1/A a t Fig. A.5 DIRAC delta function with ε>0 In Fig. A.5 the ”modified”delta function 1/ε for a<t<a+ ε δε(t − a):= (A.9) 0 for t<a and t>a+ ε is represented,which tends to (A.6) as ε tends to zero, where the hatched area in Fig. A.5 is always unity. Hence, the property (A.7) is valid. If any continuous function f(t) is multiplied by the DIRAC delta function δ(t − a) the product vanishes everywhere except at t = a, while the value f(a) is independent of t and can therefore be written outside the integral. Thus, considering (A.7), we arrive at the result (A.8), which is also applied in the collocation method according to &L ! δ(x − xi)R(x)dx = R(Xi) =0 , (A.10) 0 where R(x) is the residuum of an approximation, for instance ΔΦ − g(x)= R(x) =0 ,andXi is an optimal selected collocation point. The integral in (A.10) is setting over a domain L considered. 290 A The HEAVISIDE and DIRAC Functions The collocation method can be shown to be a special case of the weighted- residual method &L ! Wi(x)R(x)dx =0 , (A.11) 0 where Wi(x) are weight functions (BETTEN, 2004). A relation between the unit step function (A.1) and the unit impulse func- tion (A.6) is given by d δ(t − a)= H(t − a) ≡ H˙ (t − a) (A.12) dt and may be deduced in the following way. The modified delta function (A.9) can be represented by the HEAVISIDE function (A.1) as 1 δ (t − a)= [H(t − a) − H(t − a − ε)] (A.13a) ε ε or for a =0according to 1 δ (t)= [H(t) − H(t − ε)] . (A.13b) ε ε Then, we immediately find the DIRAC delta function by forming the follow- ing limit H(t) − H(t − ε) δ(t) = lim δε(t) = lim = H˙ (t) (A.14) ε→0 ε→0 ε in accordance with (A.12), that is, the DIRAC delta function is the deriva- tion of the HEAVISIDE function. This relation is illustrated in Fig. A.6a,b by comparing Fig. A.1 with Fig. A.5. A 3.mws > with(stats): > with(statevalf): > H:=statevalf[pdf,normald[1,0.2]]: > delta:=statevalf[cdf,normald[1,0.2]]: > plot({H(t),delta(t)},t=0..2,thickness=3); > H:=statevalf[pdf,normald[1,0.03]]: > delta:=statevalf[cdf,normald[1,0.03]]: > plot({H(t),delta(t)}, > t=0..2,0..2,thickness=3); ATheHEAVISIDE and DIRAC Functions 291 2 δ (t−1; 0.2) 1.5 H(t−1; 0.2) 1 0.5 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 1t t Fig. A.6a Relation between the modified HEAVISIDE function (A.16) and the modified DIRAC function (A.15); parameters: a =1, σ =0.2 2 1.8 δ(t−1; 0.03) 1.6 1.4 1.2 H(t−1; 0.03) 1 0.8 0.6 0.4 0.2 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 1t t Fig. A.6b Relation between the modified HEAVISIDE function (A.16) and the modified DIRAC function (A.15); parameters: a =1, σ =0.03 292 A The HEAVISIDE and DIRAC Functions As an example, the normal distribution (GAUSS distribution) 2 1 1 t − a −∞ <t<∞, δ(t − a; σ):= √ exp − (A.15) σ 2π 2 σ σ>0 is considered in Fig. A.6 as a modified DIRAC delta function, and is, ac- cording to (A.14), the derivative of the modified (continuous) HEAVISIDE function &t 2 1 1 x − a H(t − a; σ):= √ exp − dx . (A.16) σ 2π 2 σ −∞ The parameter σ in (A.16) regulates the continuous transition of the HEAVI- SIDE function at the position t = a of the step. The GAUSS distribution (A.15) has the property (A.7) or &∞ δ(t − a; σ)dt =1 , (A.17) −∞ as can be shown by utilizing the MAPLE software, hence, it is a suitable impulse function. A 4.mws > delta(t):=(1/sigma/sqrt(2*Pi))* > exp((-1/2)*((t-a)/sigma)ˆ2); 2 √ (− (t−a) ) 1 2 e 2 σ2 δ(t):= √ 2 σ π > Int(delta,t=0..infinity)=int(subs(a=1, > sigma=1./10, delta(t)),t=0..infinity); & ∞ δdt=1.000000000 0 In the following, let us discuss the modified (continuous) HEAVISIDE function 1 2Dt H(t − a; D):= arctan , (A.18) π a2 − t2 where the parameter D ≥ 0 regulates the continuous transition at the posi- tion t = a of the step, (Fig. A.7). For D =0, we arrive at the ”original” HEAVISIDE function (Fig. A.7). ATheHEAVISIDE and DIRAC Functions 293 Remark: The formula (A.18) remembers us at the phase difference ϕ between the impressed force or impressed support movement and the resulting steady-state vibration of a damped system. In that case the parameter D is the damping factor, while the variable t is interpreted as the frequency ratio Ω/ω. > y(t):=2*D*t; x(t):=1-tˆ2; A 5.mws y(t):=2Dt 2 x(t):=1− t > H(t):=(1/Pi)*arctan(y(t),x(t)); arctan(2 D t, 1 − t2) H(t):= π > plot1:=plot(subs(D=infinity,H(t)), > t=0..3,0..1): > plot2:=plot(subs(D=0.5,H(t)),t=0..3,0..1): > plot3:=plot(subs(D=0.1,H(t)),t=0..3,0..1): > plot4:=plot(subs(D=0.05,H(t)),t=0..3,0..1): > plot5:=plot(subs(D=0,H(t)),t=0..3,0..1): > plots[display]({plot1,plot2,plot3, > plot4,plot5}); D=0 1 H(t−1; D) D=0.1 0.8 D=0.5 0.6 D= 8 0.4 0.2 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 2.2 2.4 2.6 2.8 3 tt Fig.
Recommended publications
  • Distributions:The Evolutionof a Mathematicaltheory
    Historia Mathematics 10 (1983) 149-183 DISTRIBUTIONS:THE EVOLUTIONOF A MATHEMATICALTHEORY BY JOHN SYNOWIEC INDIANA UNIVERSITY NORTHWEST, GARY, INDIANA 46408 SUMMARIES The theory of distributions, or generalized func- tions, evolved from various concepts of generalized solutions of partial differential equations and gener- alized differentiation. Some of the principal steps in this evolution are described in this paper. La thgorie des distributions, ou des fonctions g&&alis~es, s'est d&eloppeg 2 partir de divers con- cepts de solutions g&&alis6es d'gquations aux d&i- &es partielles et de diffgrentiation g&&alis6e. Quelques-unes des principales &apes de cette &olution sont d&rites dans cet article. Die Theorie der Distributionen oder verallgemein- erten Funktionen entwickelte sich aus verschiedenen Begriffen von verallgemeinerten Lasungen der partiellen Differentialgleichungen und der verallgemeinerten Ableitungen. In diesem Artikel werden einige der wesentlichen Schritte dieser Entwicklung beschrieben. 1. INTRODUCTION The founder of the theory of distributions is rightly con- sidered to be Laurent Schwartz. Not only did he write the first systematic paper on the subject [Schwartz 19451, which, along with another paper [1947-19481, already contained most of the basic ideas, but he also wrote expository papers on distributions for electrical engineers [19481. Furthermore, he lectured effec- tively on his work, for example, at the Canadian Mathematical Congress [1949]. He showed how to apply distributions to partial differential equations [19SObl and wrote the first general trea- tise on the subject [19SOa, 19511. Recognition of his contri- butions came in 1950 when he was awarded the Fields' Medal at the International Congress of Mathematicians, and in his accep- tance address to the congress Schwartz took the opportunity to announce his celebrated "kernel theorem" [195Oc].
    [Show full text]
  • Arxiv:1404.7630V2 [Math.AT] 5 Nov 2014 Asoffsae,Se[S4 P8,Vr6.Isedof Instead Ver66]
    PROPER BASE CHANGE FOR SEPARATED LOCALLY PROPER MAPS OLAF M. SCHNÜRER AND WOLFGANG SOERGEL Abstract. We introduce and study the notion of a locally proper map between topological spaces. We show that fundamental con- structions of sheaf theory, more precisely proper base change, pro- jection formula, and Verdier duality, can be extended from contin- uous maps between locally compact Hausdorff spaces to separated locally proper maps between arbitrary topological spaces. Contents 1. Introduction 1 2. Locally proper maps 3 3. Proper direct image 5 4. Proper base change 7 5. Derived proper direct image 9 6. Projection formula 11 7. Verdier duality 12 8. The case of unbounded derived categories 15 9. Remindersfromtopology 17 10. Reminders from sheaf theory 19 11. Representability and adjoints 21 12. Remarks on derived functors 22 References 23 arXiv:1404.7630v2 [math.AT] 5 Nov 2014 1. Introduction The proper direct image functor f! and its right derived functor Rf! are defined for any continuous map f : Y → X of locally compact Hausdorff spaces, see [KS94, Spa88, Ver66]. Instead of f! and Rf! we will use the notation f(!) and f! for these functors. They are embedded into a whole collection of formulas known as the six-functor-formalism of Grothendieck. Under the assumption that the proper direct image functor f(!) has finite cohomological dimension, Verdier proved that its ! derived functor f! admits a right adjoint f . Olaf Schnürer was supported by the SPP 1388 and the SFB/TR 45 of the DFG. Wolfgang Soergel was supported by the SPP 1388 of the DFG. 1 2 OLAFM.SCHNÜRERANDWOLFGANGSOERGEL In this article we introduce in 2.3 the notion of a locally proper map between topological spaces and show that the above results even hold for arbitrary topological spaces if all maps whose proper direct image functors are involved are locally proper and separated.
    [Show full text]
  • Mathematical and Physical Interpretations of Fractional Derivatives and Integrals
    R. Hilfer Mathematical and Physical Interpretations of Fractional Derivatives and Integrals Abstract: Brief descriptions of various mathematical and physical interpretations of fractional derivatives and integrals have been collected into this chapter as points of reference and departure for deeper studies. “Mathematical interpre- tation” in the title means a brief description of the basic mathematical idea underlying a precise definition. “Physical interpretation” means a brief descrip- tion of the physical theory underlying an identification of the fractional order with a known physical quantity. Numerous interpretations had to be left out due to page limitations. Only a crude, rough and ready description is given for each interpretation. For precise theorems and proofs an extensive list of references can serve as a starting point. Keywords: fractional derivatives and integrals, Riemann-Liouville integrals, Weyl integrals, Riesz potentials, operational calculus, functional calculus, Mikusinski calculus, Hille-Phillips calculus, Riesz-Dunford calculus, classification, phase transitions, time evolution, anomalous diffusion, continuous time random walks Mathematics Subject Classification 2010: 26A33, 34A08, 35R11 published in: Handbook of Fractional Calculus: Basic Theory, Vol. 1, Ch. 3, pp. 47-86, de Gruyter, Berlin (2019) ISBN 978-3-11-057162-2 R. Hilfer, ICP, Fakultät für Mathematik und Physik, Universität Stuttgart, Allmandring 3, 70569 Stuttgart, Deutschland DOI https://doi.org/10.1515/9783110571622 Interpretations 1 1 Prolegomena
    [Show full text]
  • MATH 418 Assignment #7 1. Let R, S, T Be Positive Real Numbers Such That R
    MATH 418 Assignment #7 1. Let r, s, t be positive real numbers such that r + s + t = 1. Suppose that f, g, h are nonnegative measurable functions on a measure space (X, S, µ). Prove that Z r s t r s t f g h dµ ≤ kfk1kgk1khk1. X s t Proof . Let u := g s+t h s+t . Then f rgsht = f rus+t. By H¨older’s inequality we have Z Z rZ s+t r s+t r 1/r s+t 1/(s+t) r s+t f u dµ ≤ (f ) dµ (u ) dµ = kfk1kuk1 . X X X For the same reason, we have Z Z s t s t s+t s+t s+t s+t kuk1 = u dµ = g h dµ ≤ kgk1 khk1 . X X Consequently, Z r s t r s+t r s t f g h dµ ≤ kfk1kuk1 ≤ kfk1kgk1khk1. X 2. Let Cc(IR) be the linear space of all continuous functions on IR with compact support. (a) For 1 ≤ p < ∞, prove that Cc(IR) is dense in Lp(IR). Proof . Let X be the closure of Cc(IR) in Lp(IR). Then X is a linear space. We wish to show X = Lp(IR). First, if I = (a, b) with −∞ < a < b < ∞, then χI ∈ X. Indeed, for n ∈ IN, let gn the function on IR given by gn(x) := 1 for x ∈ [a + 1/n, b − 1/n], gn(x) := 0 for x ∈ IR \ (a, b), gn(x) := n(x − a) for a ≤ x ≤ a + 1/n and gn(x) := n(b − x) for b − 1/n ≤ x ≤ b.
    [Show full text]
  • On Fractional Whittaker Equation and Operational Calculus
    J. Math. Sci. Univ. Tokyo 20 (2013), 127–146. On Fractional Whittaker Equation and Operational Calculus By M. M. Rodrigues and N. Vieira Abstract. This paper is intended to investigate a fractional dif- ferential Whittaker’s equation of order 2α, with α ∈]0, 1], involving the Riemann-Liouville derivative. We seek a possible solution in terms of power series by using operational approach for the Laplace and Mellin transform. A recurrence relation for coefficients is obtained. The exis- tence and uniqueness of solutions is discussed via Banach fixed point theorem. 1. Introduction The Whittaker functions arise as solutions of the Whittaker differential equation (see [4], Vol.1)). These functions have acquired a significant in- creasing due to its frequent use in applications of mathematics to physical and technical problems [1]. Moreover, they are closely related to the con- fluent hypergeometric functions, which play an important role in various branches of applied mathematics and theoretical physics, for instance, fluid mechanics, electromagnetic diffraction theory, and atomic structure theory. This justifies the continuous effort in studying properties of these functions and in gathering information about them. As far as the authors aware, there were no attempts to study the corresponding fractional Whittaker equation (see below). Fractional differential equations are widely used for modeling anomalous relaxation and diffusion phenomena (see [3], Ch. 5, [6], Ch. 2). A systematic development of the analytic theory of fractional differential equations with variable coefficients can be found, for instance, in the books of Samko, Kilbas and Marichev (see [13], Ch. 3). 2010 Mathematics Subject Classification. Primary 35R11; Secondary 34B30, 42A38, 47H10.
    [Show full text]
  • Origin of Probability in Quantum Mechanics and the Physical Interpretation of the Wave Function
    Origin of Probability in Quantum Mechanics and the Physical Interpretation of the Wave Function Shuming Wen ( [email protected] ) Faculty of Land and Resources Engineering, Kunming University of Science and Technology. Research Article Keywords: probability origin, wave-function collapse, uncertainty principle, quantum tunnelling, double-slit and single-slit experiments Posted Date: November 16th, 2020 DOI: https://doi.org/10.21203/rs.3.rs-95171/v2 License: This work is licensed under a Creative Commons Attribution 4.0 International License. Read Full License Origin of Probability in Quantum Mechanics and the Physical Interpretation of the Wave Function Shuming Wen Faculty of Land and Resources Engineering, Kunming University of Science and Technology, Kunming 650093 Abstract The theoretical calculation of quantum mechanics has been accurately verified by experiments, but Copenhagen interpretation with probability is still controversial. To find the source of the probability, we revised the definition of the energy quantum and reconstructed the wave function of the physical particle. Here, we found that the energy quantum ê is 6.62606896 ×10-34J instead of hν as proposed by Planck. Additionally, the value of the quality quantum ô is 7.372496 × 10-51 kg. This discontinuity of energy leads to a periodic non-uniform spatial distribution of the particles that transmit energy. A quantum objective system (QOS) consists of many physical particles whose wave function is the superposition of the wave functions of all physical particles. The probability of quantum mechanics originates from the distribution rate of the particles in the QOS per unit volume at time t and near position r. Based on the revision of the energy quantum assumption and the origin of the probability, we proposed new certainty and uncertainty relationships, explained the physical mechanism of wave-function collapse and the quantum tunnelling effect, derived the quantum theoretical expression of double-slit and single-slit experiments.
    [Show full text]
  • American Mathematical Society TRANSLATIONS Series 2 • Volume 130
    American Mathematical Society TRANSLATIONS Series 2 • Volume 130 One-Dimensional Inverse Problems of Mathematical Physics aM „ °m American Mathematical Society One-Dimensional Inverse Problems of Mathematical Physics http://dx.doi.org/10.1090/trans2/130 American Mathematical Society TRANSLATIONS Series 2 • Volume 130 One-Dimensional Inverse Problems of Mathematical Physics By M. M. Lavrent'ev K. G. Reznitskaya V. G. Yakhno do, n American Mathematical Society r, --1 Providence, Rhode Island Translated by J. R. SCHULENBERGER Translation edited by LEV J. LEIFMAN 1980 Mathematics Subject Classification (1985 Revision): Primary 35K05, 35L05, 35R30. Abstract. Problems of determining a variable coefficient and right side for hyperbolic and parabolic equations on the basis of known solutions at fixed points of space for all times are considered in this monograph. Here the desired coefficient of the equation is a function of only one coordinate, while the desired right side is a function only of time. On the basis of solution of direct problems the inverse problems are reduced to nonlinear operator equations for which uniqueness and in some cases also existence questions are investigated. The problems studied have applied importance, since they are models for interpreting data of geophysical prospecting by seismic and electric means. The monograph is of interest to mathematicians concerned with mathematical physics. Bibliography: 75 titles. Library of Congress Cataloging-in-Publication Data Lavrent'ev, M. M. (Mlkhail Milchanovich) One-dimensional inverse problems of mathematical physics. (American Mathematical Society translations; ser. 2, v. 130) Translation of: Odnomernye obratnye zadachi matematicheskoi Bibliography: p. 67. 1. Inverse problems (Differential equations) 2. Mathematical physics.
    [Show full text]
  • Engineering Viscoelasticity
    ENGINEERING VISCOELASTICITY David Roylance Department of Materials Science and Engineering Massachusetts Institute of Technology Cambridge, MA 02139 October 24, 2001 1 Introduction This document is intended to outline an important aspect of the mechanical response of polymers and polymer-matrix composites: the field of linear viscoelasticity. The topics included here are aimed at providing an instructional introduction to this large and elegant subject, and should not be taken as a thorough or comprehensive treatment. The references appearing either as footnotes to the text or listed separately at the end of the notes should be consulted for more thorough coverage. Viscoelastic response is often used as a probe in polymer science, since it is sensitive to the material’s chemistry and microstructure. The concepts and techniques presented here are important for this purpose, but the principal objective of this document is to demonstrate how linear viscoelasticity can be incorporated into the general theory of mechanics of materials, so that structures containing viscoelastic components can be designed and analyzed. While not all polymers are viscoelastic to any important practical extent, and even fewer are linearly viscoelastic1, this theory provides a usable engineering approximation for many applications in polymer and composites engineering. Even in instances requiring more elaborate treatments, the linear viscoelastic theory is a useful starting point. 2 Molecular Mechanisms When subjected to an applied stress, polymers may deform by either or both of two fundamen- tally different atomistic mechanisms. The lengths and angles of the chemical bonds connecting the atoms may distort, moving the atoms to new positions of greater internal energy.
    [Show full text]
  • Basic Electrical Engineering
    BASIC ELECTRICAL ENGINEERING V.HimaBindu V.V.S Madhuri Chandrashekar.D GOKARAJU RANGARAJU INSTITUTE OF ENGINEERING AND TECHNOLOGY (Autonomous) Index: 1. Syllabus……………………………………………….……….. .1 2. Ohm’s Law………………………………………….…………..3 3. KVL,KCL…………………………………………….……….. .4 4. Nodes,Branches& Loops…………………….……….………. 5 5. Series elements & Voltage Division………..………….……….6 6. Parallel elements & Current Division……………….………...7 7. Star-Delta transformation…………………………….………..8 8. Independent Sources …………………………………..……….9 9. Dependent sources……………………………………………12 10. Source Transformation:…………………………………….…13 11. Review of Complex Number…………………………………..16 12. Phasor Representation:………………….…………………….19 13. Phasor Relationship with a pure resistance……………..……23 14. Phasor Relationship with a pure inductance………………....24 15. Phasor Relationship with a pure capacitance………..……….25 16. Series and Parallel combinations of Inductors………….……30 17. Series and parallel connection of capacitors……………...…..32 18. Mesh Analysis…………………………………………………..34 19. Nodal Analysis……………………………………………….…37 20. Average, RMS values……………….……………………….....43 21. R-L Series Circuit……………………………………………...47 22. R-C Series circuit……………………………………………....50 23. R-L-C Series circuit…………………………………………....53 24. Real, reactive & Apparent Power…………………………….56 25. Power triangle……………………………………………….....61 26. Series Resonance……………………………………………….66 27. Parallel Resonance……………………………………………..69 28. Thevenin’s Theorem…………………………………………...72 29. Norton’s Theorem……………………………………………...75 30. Superposition Theorem………………………………………..79 31.
    [Show full text]
  • (Measure Theory for Dummies) UWEE Technical Report Number UWEETR-2006-0008
    A Measure Theory Tutorial (Measure Theory for Dummies) Maya R. Gupta {gupta}@ee.washington.edu Dept of EE, University of Washington Seattle WA, 98195-2500 UWEE Technical Report Number UWEETR-2006-0008 May 2006 Department of Electrical Engineering University of Washington Box 352500 Seattle, Washington 98195-2500 PHN: (206) 543-2150 FAX: (206) 543-3842 URL: http://www.ee.washington.edu A Measure Theory Tutorial (Measure Theory for Dummies) Maya R. Gupta {gupta}@ee.washington.edu Dept of EE, University of Washington Seattle WA, 98195-2500 University of Washington, Dept. of EE, UWEETR-2006-0008 May 2006 Abstract This tutorial is an informal introduction to measure theory for people who are interested in reading papers that use measure theory. The tutorial assumes one has had at least a year of college-level calculus, some graduate level exposure to random processes, and familiarity with terms like “closed” and “open.” The focus is on the terms and ideas relevant to applied probability and information theory. There are no proofs and no exercises. Measure theory is a bit like grammar, many people communicate clearly without worrying about all the details, but the details do exist and for good reasons. There are a number of great texts that do measure theory justice. This is not one of them. Rather this is a hack way to get the basic ideas down so you can read through research papers and follow what’s going on. Hopefully, you’ll get curious and excited enough about the details to check out some of the references for a deeper understanding.
    [Show full text]
  • Mathematics Support Class Can Succeed and Other Projects To
    Mathematics Support Class Can Succeed and Other Projects to Assist Success Georgia Department of Education Divisions for Special Education Services and Supports 1870 Twin Towers East Atlanta, Georgia 30334 Overall Content • Foundations for Success (Math Panel Report) • Effective Instruction • Mathematical Support Class • Resources • Technology Georgia Department of Education Kathy Cox, State Superintendent of Schools FOUNDATIONS FOR SUCCESS National Mathematics Advisory Panel Final Report, March 2008 Math Panel Report Two Major Themes Curricular Content Learning Processes Instructional Practices Georgia Department of Education Kathy Cox, State Superintendent of Schools Two Major Themes First Things First Learning as We Go Along • Positive results can be • In some areas, adequate achieved in a research does not exist. reasonable time at • The community will learn accessible cost by more later on the basis of addressing clearly carefully evaluated important things now practice and research. • A consistent, wise, • We should follow a community-wide effort disciplined model of will be required. continuous improvement. Georgia Department of Education Kathy Cox, State Superintendent of Schools Curricular Content Streamline the Mathematics Curriculum in Grades PreK-8: • Focus on the Critical Foundations for Algebra – Fluency with Whole Numbers – Fluency with Fractions – Particular Aspects of Geometry and Measurement • Follow a Coherent Progression, with Emphasis on Mastery of Key Topics Avoid Any Approach that Continually Revisits Topics without Closure Georgia Department of Education Kathy Cox, State Superintendent of Schools Learning Processes • Scientific Knowledge on Learning and Cognition Needs to be Applied to the classroom to Improve Student Achievement: – To prepare students for Algebra, the curriculum must simultaneously develop conceptual understanding, computational fluency, factual knowledge and problem solving skills.
    [Show full text]
  • An Analytic Exact Form of the Unit Step Function
    Mathematics and Statistics 2(7): 235-237, 2014 http://www.hrpub.org DOI: 10.13189/ms.2014.020702 An Analytic Exact Form of the Unit Step Function J. Venetis Section of Mechanics, Faculty of Applied Mathematics and Physical Sciences, National Technical University of Athens *Corresponding Author: [email protected] Copyright © 2014 Horizon Research Publishing All rights reserved. Abstract In this paper, the author obtains an analytic Meanwhile, there are many smooth analytic exact form of the unit step function, which is also known as approximations to the unit step function as it can be seen in Heaviside function and constitutes a fundamental concept of the literature [4,5,6]. Besides, Sullivan et al [7] obtained a the Operational Calculus. Particularly, this function is linear algebraic approximation to this function by means of a equivalently expressed in a closed form as the summation of linear combination of exponential functions. two inverse trigonometric functions. The novelty of this However, the majority of all these approaches lead to work is that the exact representation which is proposed here closed – form representations consisting of non - elementary is not performed in terms of non – elementary special special functions, e.g. Logistic function, Hyperfunction, or functions, e.g. Dirac delta function or Error function and Error function and also most of its algebraic exact forms are also is neither the limit of a function, nor the limit of a expressed in terms generalized integrals or infinitesimal sequence of functions with point wise or uniform terms, something that complicates the related computational convergence. Therefore it may be much more appropriate in procedures.
    [Show full text]