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Determination of the Magnetic Permeability, Electrical Conductivity
This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Citation information: DOI 10.1109/TII.2018.2885406, IEEE Transactions on Industrial Informatics TII-18-2870 1 Determination of the magnetic permeability, electrical conductivity, and thickness of ferrite metallic plates using a multi-frequency electromagnetic sensing system Mingyang Lu, Yuedong Xie, Wenqian Zhu, Anthony Peyton, and Wuliang Yin, Senior Member, IEEE Abstract—In this paper, an inverse method was developed by the sensor are not only dependent on the magnetic which can, in principle, reconstruct arbitrary permeability, permeability of the strip but is also an unwanted function of the conductivity, thickness, and lift-off with a multi-frequency electrical conductivity and thickness of the strip and the electromagnetic sensor from inductance spectroscopic distance between the strip steel and the sensor (lift-off). The measurements. confounding cross-sensitivities to these parameters need to be Both the finite element method and the Dodd & Deeds rejected by the processing algorithms applied to inductance formulation are used to solve the forward problem during the spectra. inversion process. For the inverse solution, a modified Newton– Raphson method was used to adjust each set of parameters In recent years, the eddy current technique (ECT) [2-5] and (permeability, conductivity, thickness, and lift-off) to fit the alternating current potential drop (ACPD) technique [6-8] inductances (measured or simulated) in a least-squared sense were the two primary electromagnetic non-destructive testing because of its known convergence properties. The approximate techniques (NDT) [9-21] on metals’ permeability Jacobian matrix (sensitivity matrix) for each set of the parameter measurements. -
3.Joule's Experiments
The Force of Gravity Creates Energy: The “Work” of James Prescott Joule http://www.bookrags.com/biography/james-prescott-joule-wsd/ James Prescott Joule (1818-1889) was the son of a successful British brewer. He tinkered with the tools of his father’s trade (particularly thermometers), and despite never earning an undergraduate degree, he was able to answer two rather simple questions: 1. Why is the temperature of the water at the bottom of a waterfall higher than the temperature at the top? 2. Why does an electrical current flowing through a conductor raise the temperature of water? In order to adequately investigate these questions on our own, we need to first define “temperature” and “energy.” Second, we should determine how the measurement of temperature can relate to “heat” (as energy). Third, we need to find relationships that might exist between temperature and “mechanical” energy and also between temperature and “electrical” energy. Definitions: Before continuing, please write down what you know about temperature and energy below. If you require more space, use the back. Temperature: Energy: We have used the concept of gravity to show how acceleration of freely falling objects is related mathematically to distance, time, and speed. We have also used the relationship between net force applied through a distance to define “work” in the Harvard Step Test. Now, through the work of Joule, we can equate the concepts of “work” and “energy”: Energy is the capacity of a physical system to do work. Potential energy is “stored” energy, kinetic energy is “moving” energy. One type of potential energy is that induced by the gravitational force between two objects held at a distance (there are other types of potential energy, including electrical, magnetic, chemical, nuclear, etc). -
GNBS International System of Units Booklet
I Table of INTRODUCTION CONTENTS The purpose of this booklet Learn About... 3 is to enable Guyanese to become familiar with • Guyana National Bureau 3 the metric system and, in of Standards (GNBS). particular, the International System of Units or SI Units. With most of the world We Look to the Future using the metric system of 5 measurements, these SI • Why do we need 5 units are now an intrinsic Measurement Standards? part of our lives. • The Role of Measurements 6 The meat, flour, fruit and in our Daily Lives. vegetables we buy; the pills, tablets and capsules doctors prescribe; the distances vehicles cover and boats Learn More On... 7 sail and athletes run, as • What is the SI? 7 well as fabric bought for our garments to be made • Why use the SI? 8 from are all weighed and measured using SI units. Given this trend, Guyana Learn the Units 9 must fully embrace metric • What are the SI Units? 9 measurements. Thus, this booklet intends to promote • The Basics of the Metric 11 a culture in which Guyanese System in use everyday. not only “think metric” but also actively use the SI units - The Kilogram 11 in their everyday lives. II III - The Kilometre 13 Guyana National - The Litre 15 Bureau of learn Standards Using the Basic Units 17 about... • Converting between Units 17 (GNBS) • Temperature 18 The Guyana National Bureau of Standards (GNBS) operates under • Writing Dates 19 the Ministry of Tourism, Industry and commerce as a semi - • Writing Times 19 -autonomous governmental organization responsible for standards and quality in Guyana. -
Electric Permittivity of Carbon Fiber
Carbon 143 (2019) 475e480 Contents lists available at ScienceDirect Carbon journal homepage: www.elsevier.com/locate/carbon Electric permittivity of carbon fiber * Asma A. Eddib, D.D.L. Chung Composite Materials Research Laboratory, Department of Mechanical and Aerospace Engineering, University at Buffalo, The State University of New York, Buffalo, NY, 14260-4400, USA article info abstract Article history: The electric permittivity is a fundamental material property that affects electrical, electromagnetic and Received 19 July 2018 electrochemical applications. This work provides the first determination of the permittivity of contin- Received in revised form uous carbon fibers. The measurement is conducted along the fiber axis by capacitance measurement at 25 October 2018 2 kHz using an LCR meter, with a dielectric film between specimen and electrode (necessary because an Accepted 11 November 2018 LCR meter is not designed to measure the capacitance of an electrical conductor), and with decoupling of Available online 19 November 2018 the contributions of the specimen volume and specimen-electrode interface to the measured capaci- tance. The relative permittivity is 4960 ± 662 and 3960 ± 450 for Thornel P-100 (more graphitic) and Thornel P-25 fibers (less graphitic), respectively. These values are high compared to those of discon- tinuous carbons, such as reduced graphite oxide (relative permittivity 1130), but are low compared to those of steels, which are more conductive than carbon fibers. The high permittivity of carbon fibers compared to discontinuous carbons is attributed to the continuity of the fibers and the consequent substantial distance that the electrons can move during polarization. The P-100/P-25 permittivity ratio is 1.3, whereas the P-100/P-25 conductivity ratio is 67. -
Network Map of Knowledge And
Humphry Davy George Grosz Patrick Galvin August Wilhelm von Hofmann Mervyn Gotsman Peter Blake Willa Cather Norman Vincent Peale Hans Holbein the Elder David Bomberg Hans Lewy Mark Ryden Juan Gris Ian Stevenson Charles Coleman (English painter) Mauritz de Haas David Drake Donald E. Westlake John Morton Blum Yehuda Amichai Stephen Smale Bernd and Hilla Becher Vitsentzos Kornaros Maxfield Parrish L. Sprague de Camp Derek Jarman Baron Carl von Rokitansky John LaFarge Richard Francis Burton Jamie Hewlett George Sterling Sergei Winogradsky Federico Halbherr Jean-Léon Gérôme William M. Bass Roy Lichtenstein Jacob Isaakszoon van Ruisdael Tony Cliff Julia Margaret Cameron Arnold Sommerfeld Adrian Willaert Olga Arsenievna Oleinik LeMoine Fitzgerald Christian Krohg Wilfred Thesiger Jean-Joseph Benjamin-Constant Eva Hesse `Abd Allah ibn `Abbas Him Mark Lai Clark Ashton Smith Clint Eastwood Therkel Mathiassen Bettie Page Frank DuMond Peter Whittle Salvador Espriu Gaetano Fichera William Cubley Jean Tinguely Amado Nervo Sarat Chandra Chattopadhyay Ferdinand Hodler Françoise Sagan Dave Meltzer Anton Julius Carlson Bela Cikoš Sesija John Cleese Kan Nyunt Charlotte Lamb Benjamin Silliman Howard Hendricks Jim Russell (cartoonist) Kate Chopin Gary Becker Harvey Kurtzman Michel Tapié John C. Maxwell Stan Pitt Henry Lawson Gustave Boulanger Wayne Shorter Irshad Kamil Joseph Greenberg Dungeons & Dragons Serbian epic poetry Adrian Ludwig Richter Eliseu Visconti Albert Maignan Syed Nazeer Husain Hakushu Kitahara Lim Cheng Hoe David Brin Bernard Ogilvie Dodge Star Wars Karel Capek Hudson River School Alfred Hitchcock Vladimir Colin Robert Kroetsch Shah Abdul Latif Bhittai Stephen Sondheim Robert Ludlum Frank Frazetta Walter Tevis Sax Rohmer Rafael Sabatini Ralph Nader Manon Gropius Aristide Maillol Ed Roth Jonathan Dordick Abdur Razzaq (Professor) John W. -
Numerical Modelling of VLF Radio Wave Propagation Through Earth-Ionosphere Waveguide and Its Application to Sudden Ionospheric Disturbances
Numerical Modelling of VLF Radio Wave Propagation through Earth-Ionosphere Waveguide and its application to Sudden Ionospheric istur!ances Thesis submitted for the degree of octor of Philosoph# (Science% in Ph#sics (Theoretical) of the &niversity of 'alcutta Su(a# Pal Ma#8, )*+, CERTIFICATE FROM THE SUPERVISOR This is to certify that the thesis entitled "Numerical Modelling of VLF Radio Wave Propagation through Earth-Ionosphere waveguide and its application to !udden Ionospheric Distur#ances", submitted by Mr. Sujay Pal who got his name registered on $%&$'&%$(( for the award of Ph.D. )!cience* degree of the Universit, of Calcutta. absolutely based upon his own work under the supervision of Professor !andip K. Cha0ra#arti and that neither this thesis nor any part of it has been submitted for any degree/diploma or any other academic award anywhere before. Prof. !andip K. -ha0ra#arti Senior Professor & Head Department of #strophysics & Cosmology S. N. Bose National Centre for Basic Sciences JD Block, Sector())), Salt *ake, +olkata 7---./, India TO My PARENTS i ABSTRACT Very Low Frequency (VLF) radio waves with frequency in the range 3 30 kHz ∼ propagate within the Earth-ionosphere waveguide (EIWG) for#ed $y the Earth as the %ower $oundary and the %ower ionosphere (50 100 k#) as the upper $oundary ∼ of the waveguide. These waves are generated from #an-#ade transmitters as wel% as fro# lightnings or other natura% sources( *tudy of these waves is very i#portant since they are the only tool to diagnose the %ower ionosphere( Lower part of the Earth+s ionosphere ranging &0 90 km is known as the -- ∼ region of the ionosphere( *olar Lyman-α radiation at '.'./ n# and EUV radiation in 80 '''.& n# are #ain%y responsib%e for for#ing the --region through the ∼ ionization of 123N 23O 2 during day time( The VLF propagation takes p%ace $etween the Earth+s surface and the --region at the day time. -
Units in Electromagnetism (PDF)
Units in electromagnetism Almost all textbooks on electricity and magnetism (including Griffiths’s book) use the same set of units | the so-called rationalized or Giorgi units. These have the advantage of common use. On the other hand there are all sorts of \0"s and \µ0"s to memorize. Could anyone think of a system that doesn't have all this junk to memorize? Yes, Carl Friedrich Gauss could. This problem describes the Gaussian system of units. [In working this problem, keep in mind the distinction between \dimensions" (like length, time, and charge) and \units" (like meters, seconds, and coulombs).] a. In the Gaussian system, the measure of charge is q q~ = p : 4π0 Write down Coulomb's law in the Gaussian system. Show that in this system, the dimensions ofq ~ are [length]3=2[mass]1=2[time]−1: There is no need, in this system, for a unit of charge like the coulomb, which is independent of the units of mass, length, and time. b. The electric field in the Gaussian system is given by F~ E~~ = : q~ How is this measure of electric field (E~~) related to the standard (Giorgi) field (E~ )? What are the dimensions of E~~? c. The magnetic field in the Gaussian system is given by r4π B~~ = B~ : µ0 What are the dimensions of B~~ and how do they compare to the dimensions of E~~? d. In the Giorgi system, the Lorentz force law is F~ = q(E~ + ~v × B~ ): p What is the Lorentz force law expressed in the Gaussian system? Recall that c = 1= 0µ0. -
A Brief History of Nuclear Astrophysics
A BRIEF HISTORY OF NUCLEAR ASTROPHYSICS PART I THE ENERGY OF THE SUN AND STARS Nikos Prantzos Institut d’Astrophysique de Paris Stellar Origin of Energy the Elements Nuclear Astrophysics Astronomy Nuclear Physics Thermodynamics: the energy of the Sun and the age of the Earth 1847 : Robert Julius von Mayer Sun heated by fall of meteors 1854 : Hermann von Helmholtz Gravitational energy of Kant’s contracting protosolar nebula of gas and dust turns into kinetic energy Timescale ~ EGrav/LSun ~ 30 My 1850s : William Thompson (Lord Kelvin) Sun heated at formation from meteorite fall, now « an incadescent liquid mass » cooling Age 10 – 100 My 1859: Charles Darwin Origin of species : Rate of erosion of the Weald valley is 1 inch/century or 22 miles wild (X 1100 feet high) in 300 My Such large Earth ages also required by geologists, like Charles Lyell A gaseous, contracting and heating Sun 푀⊙ Mean solar density : ~1.35 g/cc Sun liquid Incompressible = 4 3 푅 3 ⊙ 1870s: J. Homer Lane ; 1880s :August Ritter : Sun gaseous Compressible As it shrinks, it releases gravitational energy AND it gets hotter Earth Mayer – Kelvin - Helmholtz Helmholtz - Ritter A gaseous, contracting and heating Sun 푀⊙ Mean solar density : ~1.35 g/cc Sun liquid Incompressible = 4 3 푅 3 ⊙ 1870s: J. Homer Lane ; 1880s :August Ritter : Sun gaseous Compressible As it shrinks, it releases gravitational energy AND it gets hotter Earth Mayer – Kelvin - Helmholtz Helmholtz - Ritter A gaseous, contracting and heating Sun 푀⊙ Mean solar density : ~1.35 g/cc Sun liquid Incompressible = 4 3 푅 3 ⊙ 1870s: J. -
Misura E Strumenti Di Misura
® MISURA E STRUMENTI DI MISURA (G) MISURA: g = G : grandezza (numero) U(G) U(G) : unita' di misura di G Come si effettua la misura ? diretta MISURA indiretta confronto diretto con unita' di misura DIRETTA: (Grandezze omogenee) con strumento "tarato" es. : termometro, voltmetro ... INDIRETTA: dalla relazione fisica con altre grandezze es. : P = F/S STRUMENTO DI MISURA: dispositivo per determinare g 30 RIVELATORE: sensibile a grandezza da misurare (sollecitazione) TRASDUTTORE: trasforma sollecitazione STRUMENTO in grandezza facilmente misurabile VISUALIZZATORE: visualizza grandezza trasformata RIVELATORE: Mercurio Es. TERMOMETRO TRASDUTTORE: Mercurio + capillare VISUALIZZATORE: capillare + scala tarata RIVELATORE: bobina mobile in campo magnetico Es. AMPEROMETRO TRASDUTTORE: movimento bobina (rotazione ago) VISUALIZZATORE: posizione ago su scala "tarata" 31 CARATTERISTICHE STRUMENTO INTERVALLO FUNZ. (valore min-max grandezza) PRONTEZZA: tempo necessario per reagire alla sollecitazione τ τ = tempo caratteristico strumento τ (termometro) ~ secondi τ (oscilloscopio) ~ 10 -9 s SENSIBILITA`: ∆R(G) dR R(G): risposta S = = ∆V(G) dV V(G): valore grandezza se R lineare in V(G): S = cost. Altrimenti S funzione di V(G) (Ohmetro) Dimensioni : [G] -1 Es. Bilancia: S in DIV/mg 32 PRECISIONE: capacita' strumento a dare stessa risposta a stessa sollecitazione MISURE RIPETUTE (sensibilit : 1/∆g) N N g(G) g(G) ∆g GIUSTEZZA: assenza di effetti sistematici Difetto strumento (termometro: capillare a sezione variabile) Uso strumento in condizioni errate (regolo -
The Revised SI for the Kilogram
Out with the Old, in with the New: The Revised SI for the kilogram Aletta Karsten, Thapelo Mametja and Henk Potgieter [email protected] Outline • Background (SI and Revised SI) • What is SI units? • Why change? • How? • When? • South African perspective • Si sphere • Kibble Balance What is a SI unit? • The SI is defined by the SI Brochure, which is published by the BIPM. • The recommended practical system of units of measurement is the International System of Units (Système International d'Unités, with international abbreviation SI). • This SI consists of a set of base units, prefixes and derived units. • The SI is not static but evolves to match the world's increasingly demanding requirements for measurement. History of SI • First milestone • Creation of the decimal metric system at the time of the French Revolution • Deposition of two platinum standards representing the metre and the kilogram, on 22 June 1799, in the Archives de la République in Paris • Signing of the Metre Convention on 20 May 1875 • Created the BIPM and established the CGPM and the CIPM • Work began on the construction of new international prototypes of the metre and kilogram. • In 1889 the 1st CGPM sanctioned the international prototypes for the metre and the kilogram. • Together with the astronomical second as the unit of time, these units constituted a three-dimensional mechanical unit system similar to the CGS system, but with the base units metre, kilogram, and second, the MKS system. Changes in measurement standards (not new) Mass Redefinition of SI • Link to fundamental constants of nature • More accurate over time 1889 https://www.bipm.org/en/measurement-units/rev-si/ Which units will be redefined? Why? • The revision of the SI will ensure that the SI continues to meet the needs of science, technology, and commerce in the 21st century. -
On the First Electromagnetic Measurement of the Velocity of Light by Wilhelm Weber and Rudolf Kohlrausch
Andre Koch Torres Assis On the First Electromagnetic Measurement of the Velocity of Light by Wilhelm Weber and Rudolf Kohlrausch Abstract The electrostatic, electrodynamic and electromagnetic systems of units utilized during last century by Ampère, Gauss, Weber, Maxwell and all the others are analyzed. It is shown how the constant c was introduced in physics by Weber's force of 1846. It is shown that it has the unit of velocity and is the ratio of the electromagnetic and electrostatic units of charge. Weber and Kohlrausch's experiment of 1855 to determine c is quoted, emphasizing that they were the first to measure this quantity and obtained the same value as that of light velocity in vacuum. It is shown how Kirchhoff in 1857 and Weber (1857-64) independently of one another obtained the fact that an electromagnetic signal propagates at light velocity along a thin wire of negligible resistivity. They obtained the telegraphy equation utilizing Weber’s action at a distance force. This was accomplished before the development of Maxwell’s electromagnetic theory of light and before Heaviside’s work. 1. Introduction In this work the introduction of the constant c in electromagnetism by Wilhelm Weber in 1846 is analyzed. It is the ratio of electromagnetic and electrostatic units of charge, one of the most fundamental constants of nature. The meaning of this constant is discussed, the first measurement performed by Weber and Kohlrausch in 1855, and the derivation of the telegraphy equation by Kirchhoff and Weber in 1857. Initially the basic systems of units utilized during last century for describing electromagnetic quantities is presented, along with a short review of Weber’s electrodynamics. -
SKIFFS: Superconducting Kinetic Inductance Field-Frequency Sensors for Sensitive Magnetometry in Moderate Background Magnetic Fields
SKIFFS: Superconducting Kinetic Inductance Field-Frequency Sensors for sensitive magnetometry in moderate background magnetic fields Cite as: Appl. Phys. Lett. 113, 172601 (2018); https://doi.org/10.1063/1.5049615 Submitted: 24 July 2018 . Accepted: 10 October 2018 . Published Online: 25 October 2018 A. T. Asfaw , E. I. Kleinbaum, T. M. Hazard , A. Gyenis, A. A. Houck, and S. A. Lyon ARTICLES YOU MAY BE INTERESTED IN Multi-frequency spin manipulation using rapidly tunable superconducting coplanar waveguide microresonators Applied Physics Letters 111, 032601 (2017); https://doi.org/10.1063/1.4993930 Publisher's Note: “Anomalous Nernst effect in Ir22Mn78/Co20Fe60B20/MgO layers with perpendicular magnetic anisotropy” [Appl. Phys. Lett. 111, 222401 (2017)] Applied Physics Letters 113, 179901 (2018); https://doi.org/10.1063/1.5018606 Tunneling anomalous Hall effect in a ferroelectric tunnel junction Applied Physics Letters 113, 172405 (2018); https://doi.org/10.1063/1.5051629 Appl. Phys. Lett. 113, 172601 (2018); https://doi.org/10.1063/1.5049615 113, 172601 © 2018 Author(s). APPLIED PHYSICS LETTERS 113, 172601 (2018) SKIFFS: Superconducting Kinetic Inductance Field-Frequency Sensors for sensitive magnetometry in moderate background magnetic fields A. T. Asfaw,a) E. I. Kleinbaum, T. M. Hazard, A. Gyenis, A. A. Houck, and S. A. Lyon Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA (Received 24 July 2018; accepted 10 October 2018; published online 25 October 2018) We describe sensitive magnetometry using lumped-element resonators fabricated from a supercon- ducting thin film of NbTiN. Taking advantage of the large kinetic inductance of the superconduc- tor, we demonstrate a continuous resonance frequency shift of 27 MHz for a change in the magnetic field of 1.8 lT within a perpendicular background field of 60 mT.