Sánchez León, Belisario
2014-01-01
Our expertise is the study of more than 2,000 cases of Colles' fractures. Colles name should in this case to synthesize the type of fractures of the lower end of the radius. There have been various proposed classifications according to the different fracture lines can be demonstrated radiologically in the region of the wrist. We believe that these ratings should only be retained if the concept of the articular fracture or not in the classical sense, since it has great value in the functional ...
Osteoporose og Colles' fraktur
DEFF Research Database (Denmark)
Hindsø, K; Lauritzen, J B
2001-01-01
We describe the connection between osteoporosis and Colles' fractures of the distal radius from an epidemiological and aetiological point of view. In addition, the value of these fractures as markers of osteoporosis and future risk of fracture is assessed. Several studies have clearly shown an ep...
International Nuclear Information System (INIS)
Kinsler, Paul; Tan Jiajun; Thio, Timothy C Y; Trant, Claire; Kandapper, Navin
2012-01-01
Most of us will have at some time thrown a pebble into water, and watched the ripples spread outwards and fade away. But now there is also a way to reverse the process, and make those ripples turn around and reconverge again, …and again, and again. To do this we have designed the Maxwell's fishpond, a water wave or ‘transformation aquatics’ version of the Maxwell's fisheye lens (Tyc et al 2011 New J. Phys. 13 115004; Luneburg 1964 Mathematical Theory of Optics). These are transformation devices where wave propagation on the surface of a sphere is modelled using a flat device with spatially varying properties. And just as for rays from a point source on a sphere, a wave disturbance in a Maxwell's fisheye or fishpond spreads out at first, but then reforms itself at its opposite (or complementary) point. Here we show how such a device can be made for water waves, partly in friendly competition with comparable electromagnetic devices (Ma et al 2011 New J. Phys. 13 033016) and partly as an accessible and fun demonstration of the power of transformation mechanics. To the eye, our Maxwell's fishpond was capable of reforming a disturbance up to five times, although such a feat required taking considerable care, close observation, and a little luck. (paper)
Colles' fracture due to weight lifting
Rowe, P. H.
1979-01-01
The case report of a weightlifter who sustained a Colles fracture is described. Wrist injuries sustained in weightlifitng are reviewed. They highlight the need for proper instruction and supervision in this sport. Imagesp130-ap130-b PMID:486885
Nieuwenhuizen, Theo M.; Allahverdyan, Armen E.
2002-11-01
Maxwell's demon is a tiny but fine-fingered being, capable to extract work from a system at instantaneous equilibrium, without needing energy input or information erasure. In the 20'th century many workers have claimed that the demon cannot operate. Here the point of view is taken that this exorcism of the demon never applied, since one did not consider Maxwell's original invention. For a Brownian particle coupled to a quantum bath it was shown by us that quantum entanglement can allow extraction of work from a non-equilibrium system coupled to a single bath. And mesoscopic work sources may establish work extraction cycles even when they are coupled to equilibrium mesoscopic systems immersed in a macroscopic thermal bath. Quantum entanglement and mesocopicity are now identified with (true) Maxwell demons.
CERN lends a hand to Collège de Prévessin
2013-01-01
In 1973, the French government, in collaboration with CERN, created the Lycée International in Ferney-Voltaire: a public high school that would take in the children of international staff. Linguistic and cultural enrichment was one of the objectives behind the school, bringing French children together with children of other mother tongues in the same classroom. The Lycée has various international sections, known as national programmes, offering education in a number of languages. The Collège and Lycée received official international status in 1978, and since then the French Ministry of Education has assumed responsiblity for the school. To complement Collège and Lycée education, on Tuesday afternoons since 1975 pupils in Pays-de-Gex primary schools have been exempt from class so that they can follow education in their mother tongue (Dutch, English, German, Italian, Spanish or Swedish) at the Collège/Lycée. ...
Energy Technology Data Exchange (ETDEWEB)
Fresneda, R., E-mail: rodrigo.fresneda@ufabc.edu.br [Universidade Federal do ABC (UFABC), Santo Andre, SP (Brazil); Baldiotti, M.C.; Pereira, T.S., E-mail: baldiotti@uel.br, E-mail: tspereira@uel.br [Universidade Estadual de Londrina (UEL), Londrina, PR (Brazil). Departamento de Fisica
2015-06-15
We propose a gauge-invariant model of propagating torsion which couples to the Maxwell field and to charged particles. As a result, we have an Abelian gauge-invariant action leading to a theory with nonzero torsion consistent with available experimental data, which can be used to establish a lower bound for our new coupling parameter. (author)
Possible salt tectonics in Ariadnes Colles ?
Wendt, L.; Gasselt, S. V.; Neukum, G.
2008-09-01
Location Ariadnes Colles and the chaotic terrains Atlantis Chaos, Gorgonum Chaos and a further, unnamed chaotic terrain centred at 37°S, 164.4°W form individual provinces of hummocky terrain located at the deepest parts of Eridania Basin, the putative source region of Ma'adim Vallis [1,2,3,4]. The location was recently proposed as a MSL landing site [5]. Previous studies The individual knobs within Ariadnes Colles range between flat-topped mesas of up to 10 km in width and 200 m of relief down to small cone-shaped hills of only a few hundred meters in width [2] (Fig.1). Although classified as chaotic terrain, this area differs significantly from the chaotic terrains found elsewhere on Mars. The hills consist of a light-toned, indurated material [3, 5] covered by dark rock [1]. Howard and Moore [3] noted that the smaller knobs exhibit a more rounded top, are lower in elevation and are found close to the borders of the knob field, whereas the more mesa-like hills are concentrated towards its centre. They also noted that the light-toned hill tops are dissected by linear features they interpreted as joints. The mineralogy of this region is very diverse. Preliminary results based on CRISM data are consistent with the presence of phyllosilicates, sulphates and/or hydrated silica and pyroxene [5]. New obserations Our investigations using HRSC imagery confirm this overall pattern. The smaller hills consist exclusively of light-toned material and are covered only partly by a thin veneer of dust (Fig. 2). Their bases are angular or irregularly shaped and their tops are rounded to peaked, but never exhibit a mesa-like flat top. In contrast, the much larger mesas are always built up by basaltic material, which is superimposed on the bright knobs. Figure 3 shows a HiRISE image of one of the lighttoned knobs. It can be clearly seen that the light-toned material rises from beneath the inter-knob lava which covered it prior to erosion. It has been eroded and forms a scarp near
Mathematics and Maxwell's equations
International Nuclear Information System (INIS)
Boozer, Allen H
2010-01-01
The universality of mathematics and Maxwell's equations is not shared by specific plasma models. Computations become more reliable, efficient and transparent if specific plasma models are used to obtain only the information that would otherwise be missing. Constraints of high universality, such as those from mathematics and Maxwell's equations, can be obscured or lost by integrated computations. Recognition of subtle constraints of high universality is important for (1) focusing the design of control systems for magnetic field errors in tokamaks from perturbations that have little effect on the plasma to those that do, (2) clarifying the limits of applicability to astrophysics of computations of magnetic reconnection in fields that have a double periodicity or have B-vector =0 on a surface, as in a Harris sheet. Both require a degree of symmetry not expected in natural systems. Mathematics and Maxwell's equations imply that neighboring magnetic field lines characteristically separate exponentially with distance along a line. This remarkably universal phenomenon has been largely ignored, though it defines a trigger for reconnection through a critical magnitude of exponentiation. These and other examples of the importance of making distinctions and understanding constraints of high universality are explained.
James Clerk Maxwell and religion
Theerman, Paul
1986-04-01
The evolution of James Clerk Maxwell's religious beliefs is described. His college-age conversion experience and his membership in the ``Apostles'' were crucial in his religious development. In his mature statements, Maxwell denied that scientific truth was dependent on religious truth, or the reverse. Nonetheless, scientific conclusions could enrich religious contemplation of God's actions in nature. Maxwell provided a religious interpretation of the apparent uniformity and eternity of atoms.
The James Clerk Maxwell Telescope (JCMT) is a 15 m diameter telescope of high surface accuracy, operating in the millimeter and submillimeter bands, and is situated on Mauna Kea in Hawaii. The JCMT facility is described and a scientific report which includes a variety of scientific results over the years 1989 and 1990 showing the range of astronomical problems tackled with the telescope is presented. Operations, which note the decrease in both the time lost to faults and the time required for engineering and commissioning work, are described. Objectives and progress of the instrumentation program are described. A financial statement is presented.
Contributions of Maxwell to Electromagnetism
Indian Academy of Sciences (India)
Electricity history, magnetism, history, Maxwell's unification, displacement current. P V Panat. Maxwell, one of the greatest physicists of the nineteenth century, was the founder of a consistent theory of electromag- netism. However, it must be noted that significant discov- eries and intelligent efforts of Coulomb, Volta, Ampere,.
Contributions of Maxwell to Electromagnetism
Indian Academy of Sciences (India)
Maxwell, one of the greatest physicists of the nineteenth century, was the founder of a consistent theory of electromag- netism. However, it must be noted that significant discov- eries and intelligent efforts of Coulomb, Volta, Ampere,. Oersted, Faraday, Gauss, Poisson, Helmholtz and others preceded the work of Maxwell, ...
Maxwell's Contributions to Thermal Physics
Indian Academy of Sciences (India)
ing, cooling should take place. Nature is replete with such examples and Maxwell's relations provide the due ... (a) The gas molecules are point masses. The system is considered to be in equilibrium, external ..... Maxwell's velocity distribution addresses the problem for ideal gases in equilibrium, i.e., molecules are treated.
Geology of Maxwell Montes, Venus
Head, J. W.; Campbell, D. B.; Peterfreund, A. R.; Zisk, S. A.
1984-01-01
Maxwell Montes represent the most distinctive topography on the surface of Venus, rising some 11 km above mean planetary radius. The multiple data sets of the Pioneer missing and Earth based radar observations to characterize Maxwell Montes are analyzed. Maxwell Montes is a porkchop shaped feature located at the eastern end of Lakshmi Planum. The main massif trends about North 20 deg West for approximately 1000 km and the narrow handle extends several hundred km West South-West WSW from the north end of the main massif, descending down toward Lakshmi Planum. The main massif is rectilinear and approximately 500 km wide. The southern and northern edges of Maxwell Montes coincide with major topographic boundaries defining the edge of Ishtar Terra.
Energy Technology Data Exchange (ETDEWEB)
Theocharis, T.
1983-03-12
A new interpretation of Maxwell's electromagnetic theory of light is proposed, namely that the ambient Coulomb field is the medium (Maxwell's ether) of the electromagnetic radiation fields (Maxwellian waves). This investigation implies an incompleteness of the experimental foundations of the principle of special relativity, and suggests how this principle could be tested more fully. The beginning of an attempt to shape this re-interpretation in the form of an alternative theory is outlined.
Maxwell stresses and dielectric materials
Kloos, Gerhard
2008-01-01
Electrostatic stresses are a fascinating field where materials science, continuum mechanics and electrical engineering all come together. This is one of the reasons why the study of these so-called Maxwell stresses is so interesting.This treatment of electrostatic Maxwell stresses is restricted to the macroscopic description of the phenomenon, but an attempt is made to provide readers with methods and results which will allow them to deal with cases of low material symmetry, as well as with the effect of viscoelasticity upon the material response. Non-standard orientation of the material samp
Maxwell's Contributions to Thermal Physics
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 5. Maxwell's Contributions to Thermal Physics. Sisir Bhanja. General Article Volume 8 Issue 5 May 2003 pp 57-72. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/008/05/0057-0072. Keywords.
Contributions of Maxwell to Electromagnetism
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 5. Contributions of Maxwell to Electromagnetism. P V Panat. General Article Volume 8 Issue 5 May 2003 pp 17-29. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/008/05/0017-0029. Keywords.
James Clerk Maxwell: Life and science
International Nuclear Information System (INIS)
Marston, Philip L.
2016-01-01
Maxwell's life and science are presented with an account of the progression of Maxwell's research on electromagnetic theory. This is appropriate for the International Year of Light and Light-based Technologies, 2015. Maxwell's own confidence in his 1865 electromagnetic theory of light is examined, along with some of the difficulties he faced and the difficulties faced by some of his followers. Maxwell's interest in radiation pressure and electromagnetic stress is addressed, as well as subsequent developments. Some of Maxwell's other contributions to physics are discussed with an emphasis on the kinetic and molecular theory of gases. Maxwell's theistic perspective on science is illustrated, accompanied by examples of perspectives on Maxwell and his science provided by his peers and accounts of his interactions with those peers. Appendices examine the peer review of Maxwell's 1865 electromagnetic theory paper and the naming of the Maxwell Garnett effective media approximation and provide various supplemental perspectives. From Maxwell's publications and correspondence there is evidence he had a high regard for Michael Faraday. Examples of Maxwell's contributions to electromagnetic terminology are noted. - Highlights: • Maxwell’s 1865 “Dynamical theory of the electromagnetic field” is examined. • Maxwell affirmed confidence in his electromagnetic wave theory in his 1873 Treatise. • Discussion includes views and unpublished correspondence of Maxwell's contemporaries. • His contemporaries noticed the depth and breadth of Maxwell’s thought. • Maxwell’s contemporaries noticed his theistic perspective concerning science.
Power generator driven by Maxwell's demon
Chida, Kensaku; Desai, Samarth; Nishiguchi, Katsuhiko; Fujiwara, Akira
2017-01-01
Maxwell's demon is an imaginary entity that reduces the entropy of a system and generates free energy in the system. About 150 years after its proposal, theoretical studies explained the physical validity of Maxwell's demon in the context of information thermodynamics, and there have been successful experimental demonstrations of energy generation by the demon. The demon's next task is to convert the generated free energy to work that acts on the surroundings. Here, we demonstrate that Maxwel...
Possible Icelandic Tephra Found in European Colle Gnifetti Glacier
Luongo, M. T.; Kurbatov, A. V.; Erhardt, T.; Mayewski, P. A.; McCormick, M.; More, A. F.; Spaulding, N. E.; Wheatley, S. D.; Yates, M. G.; Bohleber, P. D.
2017-11-01
Volcanic ash (tephra) provides unique time markers (isochrons) that are often used as an independent age-control tool for stratigraphic correlations of paleoclimate archives from ice cores. However, little credence has been given to the notion of finding tephra in ice cores collected in the European Alps because of the relatively large distance from volcanic sources and the presumed nature of regional atmospheric circulation patterns. We filtered particles from melted ice core drilling chips gathered roughly every meter during a 2013 drilling operation at Colle Gnifetti glacier in the Swiss-Italian Alps (45°55.74'N, 7°52.58'E, 4450 m asl). One filter, preliminarily dated to the nineteenth century by annual layer counting, contained a group of six visually similar tephra particles. Analyzing their chemistry using a scanning electron microscope equipped with an energy-dispersive x-ray spectrometer established that the six particles were volcanic in origin and are very similar in composition (a distinctive geochemical signature), pointing to a single volcanic eruption source. We proposed that one of several massive nineteenth century Eastern Icelandic eruptions is a potential source given eruption timing, size, tephra dispersion area, and similarities in chemical composition. This first finding of tephra in an Alpine ice core contributes to a regional tephrochronological framework that can be adapted for future correlation among different paleoclimate sequences.
Reading Maxwell in Conceptual Physics
Bonham, Scott W.
2018-05-01
An important aspect of science education involves helping students learn to read and communicate scientific information and arguments. In this note, I would like to share a resource that I have come across which I have found to be a useful tool for helping students improve those skills, learn content material, and acquaint them with a great scientist. Specifically, this is having non-science college students in my course Light, Color and Vision read and discuss a letter by James Clerk Maxwell entitled "On the Theory of Colours in Relation to Colour-Blindness" (see Fig. 1).
Maxwell's inductions from Faraday's induction law
Redžić, D. V.
2018-03-01
In article 598 of his Treatise on Electricity and Magnetism (Maxwell 1891 A Treatise on Electricity and Magnetism (Oxford: Clarendon)), Maxwell gives a seminal analysis of Faraday's law of electromagnetic induction. We present a detailed account of the analysis, attempting to reconstruct the missing steps, and discuss some related matters.
New family of Maxwell like algebras
Energy Technology Data Exchange (ETDEWEB)
Concha, P.K., E-mail: patillusion@gmail.com [Departamento de Ciencias, Facultad de Artes y Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Av. Padre Hurtado 750, Viña del Mar (Chile); Instituto de Ciencias Físicas y Matemáticas, Universidad Austral de Chile, Casilla 567, Valdivia (Chile); Durka, R., E-mail: remigiuszdurka@gmail.com [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059, Valparaíso (Chile); Merino, N., E-mail: nemerino@gmail.com [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Casilla 4059, Valparaíso (Chile); Rodríguez, E.K., E-mail: everodriguezd@gmail.com [Departamento de Ciencias, Facultad de Artes y Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Av. Padre Hurtado 750, Viña del Mar (Chile); Instituto de Ciencias Físicas y Matemáticas, Universidad Austral de Chile, Casilla 567, Valdivia (Chile)
2016-08-10
We introduce an alternative way of closing Maxwell like algebras. We show, through a suitable change of basis, that resulting algebras are given by the direct sums of the AdS and the Maxwell algebras already known in the literature. Casting the result into the S-expansion method framework ensures the straightaway construction of the gravity theories based on a found enlargement.
New family of Maxwell like algebras
International Nuclear Information System (INIS)
Concha, P.K.; Durka, R.; Merino, N.; Rodríguez, E.K.
2016-01-01
We introduce an alternative way of closing Maxwell like algebras. We show, through a suitable change of basis, that resulting algebras are given by the direct sums of the AdS and the Maxwell algebras already known in the literature. Casting the result into the S-expansion method framework ensures the straightaway construction of the gravity theories based on a found enlargement.
J ames Clerk Maxwell and his Equations
Indian Academy of Sciences (India)
He published in 1856 the essay on 'On the stability of the motion of Saturn's rings' which won him the Adams Prize. Maxwell as a Teacher. Maxwell was appointed to the Chair of Natural Philosophy at. Marischal College, Aberdeen in 1856. He held this appointment for three sessions until the professorship was suppressed.
Maxwell superalgebras and Abelian semigroup expansion
Directory of Open Access Journals (Sweden)
P.K. Concha
2014-09-01
Full Text Available The Abelian semigroup expansion is a powerful and simple method to derive new Lie algebras from a given one. Recently it was shown that the S-expansion of so(3,2 leads us to the Maxwell algebra M. In this paper we extend this result to superalgebras, by proving that different choices of abelian semigroups S lead to interesting D=4 Maxwell Superalgebras. In particular, the minimal Maxwell superalgebra sM and the N-extended Maxwell superalgebra sM(N recently found by the Maurer–Cartan expansion procedure, are derived alternatively as an S-expansion of osp(4|N. Moreover, we show that new minimal Maxwell superalgebras type sMm+2 and their N-extended generalization can be obtained using the S-expansion procedure.
Green`s function of Maxwell`s equations and corresponding implications for iterative methods
Energy Technology Data Exchange (ETDEWEB)
Singer, B.S. [Macquarie Univ., Sydney (Australia); Fainberg, E.B. [Inst. of Physics of the Earth, Moscow (Russian Federation)
1996-12-31
Energy conservation law imposes constraints on the norm and direction of the Hilbert space vector representing a solution of Maxwell`s equations. In this paper, we derive these constrains and discuss the corresponding implications for the Green`s function of Maxwell`s equations in a dissipative medium. It is shown that Maxwell`s equations can be reduced to an integral equation with a contracting kernel. The equation can be solved using simple iterations. Software based on this algorithm have successfully been applied to a wide range of problems dealing with high contrast models. The matrix corresponding to the integral equation has a well defined spectrum. The equation can be symmetrized and solved using different approaches, for instance one of the conjugate gradient methods.
Maxwell's Multipole Vectors and the CMB
Weeks, Jeffrey R.
2004-01-01
The recently re-discovered multipole vector approach to understanding the harmonic decomposition of the cosmic microwave background traces its roots to Maxwell's Treatise on Electricity and Magnetism. Taking Maxwell's directional derivative approach as a starting point, the present article develops a fast algorithm for computing multipole vectors, with an exposition that is both simpler and better motivated than in the author's previous work. Tests show the resulting algorithm, coded up as a ...
Maxwell's equations of electrodynamics an explanation
Ball, David W
2012-01-01
Maxwell's Equations of Electrodynamics: An Explanation is a concise discussion of Maxwell's four equations of electrodynamics - the fundamental theory of electricity, magnetism, and light. It guides readers step-by-step through the vector calculus and development of each equation. Pictures and diagrams illustrate what the equations mean in basic terms. The book not only provides a fundamental description of our universe but also explains how these equations predict the fact that light is better described as "electromagnetic radiation."
2012-10-01
medical license as long as care is delivered in a military facility.26 Hurdles—Liability Medical malpractice also presents a formidable challenge. In...AIR UNIVERSITY AIR WAR COLLEGE Achieving Medical Currency via Selected Staff Integration in Civilian and Veterans Administration... Medical Facilities THOMAS W. HARRELL Colonel, USAF, MC, SFS Air War College Maxwell Paper No. 68 Maxwell Air Force Base, Alabama
Modified Maxwell equations in quantum electrodynamics
Harmuth, Henning F; Meffert, Beate
2001-01-01
Divergencies in quantum field theory referred to as "infinite zero-point energy" have been a problem for 70 years. Renormalization has always been considered an unsatisfactory remedy. In 1985 it was found that Maxwell's equations generally do not have solutions that satisfy the causality law. An additional term for magnetic dipole currents corrected this shortcoming. Rotating magnetic dipoles produce magnetic dipole currents, just as rotating electric dipoles in a material like barium titanate produce electric dipole currents. Electric dipole currents were always part of Maxwell's equations. T
Editing Cavendish: Maxwell and The Electrical Researches of Henry Cavendish
Falconer, Isobel
2015-01-01
During the last five years of his life, 1874-79, James Clerk Maxwell was absorbed in editing the electrical researches of Henry Cavendish, performed 100 years earlier. This endeavour is often assumed to be a work of duty to the Cavendish family, and an unfortunate waste of Maxwell's time. By looking at the history of Cavendish's papers, and the editorial choices that Maxwell made, this paper questions this assumption, considering the importance of Cavendish's experiments in Maxwell's electric...
Historic Landscape Survey, Maxwell AFB, Alabama
2013-08-01
and in moist soils on floodplains • Leaf litter inhibits seed germination and growth in many other plant species • Well adapted to urban areas...Small deciduous tree or large shrub • Good fall color • Approved for use on Maxwell AFB Pinus taeda Loblolly Pine Native • Tall coniferous tree
J ames Clerk Maxwell and his Equations
Indian Academy of Sciences (India)
gler maker' of the period whose students included G G Stokes, ... Besides reading with Hopkins, he also attended Stokes' lectures. ... This shrewd assess- ment was borne out later by several formulae advanced by. Maxwell where the results have proved to be correct but the mathematical arguments leading to them were ...
Maxwell's electromagnetic theory and special relativity.
Hall, Graham
2008-05-28
This paper presents a brief history of electromagnetic theory from ancient times up to the work of Maxwell and the advent of Einstein's special theory of relativity. It is divided into five convenient periods and the intention is to describe these developments for the benefit of a lay scientific audience and with the minimum of technical detail.
On fictitious domain formulations for Maxwell's equations
DEFF Research Database (Denmark)
Dahmen, W.; Jensen, Torben Klint; Urban, K.
2003-01-01
We consider fictitious domain-Lagrange multiplier formulations for variational problems in the space H(curl: Omega) derived from Maxwell's equations. Boundary conditions and the divergence constraint are imposed weakly by using Lagrange multipliers. Both the time dependent and time harmonic...
Maxwell and the classical wave particle dualism.
Mendonça, J T
2008-05-28
Maxwell's equations are one of the greatest theoretical achievements in physics of all times. They have survived three successive theoretical revolutions, associated with the advent of relativity, quantum mechanics and modern quantum field theory. In particular, they provide the theoretical framework for the understanding of the classical wave particle dualism.
Philippe Melanchton et les débuts du Collège de France
Meerhoff, K.; Castro Soares, N.; Miranda, M.; Urbano, C.M.
2008-01-01
La communication traite de la première vingtaine d'années de l'institution humaniste, fondée par François 1er, ultérieurement connue comme le Collège de France. Les premiers 'lecteurs du roi' pour l'éloquence latine ont tous subi l'influence du collaborateur et ami de M. Luther, Philippe
Synthesis and characterization of COLL-PVA/HA hybrid materials with stratified morphology.
Ficai, Maria; Andronescu, Ecaterina; Ficai, Denisa; Voicu, Georgeta; Ficai, Anton
2010-12-01
This work presents the synthesis of two hybrid materials: collagen (COLL)-polyvinyl alcohol (PVA) (1:2 wt) and collagen-polyvinyl alcohol/hydroxyapatite (HA) (1:2:3 wt). Starting from the above compositions, different kinds of composites were obtained based on the drying methods: controlled drying at 30°C and freeze drying. The materials were analysed by X-ray diffraction (XRD), Fourier transform infrared microscopy (FTIR) and scanning electron microscopy (SEM) as well as by measuring the density, porosity and absorption of xylene for each sample by Arthur method. Based on the SEM images, the freeze drying and the controlled drying could be clearly concluded to lead to porous and dense COLL-PVA/HA hybrid materials, respectively. Such materials have exhibited a stratified morphology, the distance between sheets increasing with the increase of the organic components content. Based on the literature data, the obtained COLL-PVA/HA composite materials are valuable bone grafts materials and drug delivery systems. Copyright © 2010 Elsevier B.V. All rights reserved.
Classes of exact Einstein Maxwell solutions
Komathiraj, K.; Maharaj, S. D.
2007-12-01
We find new classes of exact solutions to the Einstein Maxwell system of equations for a charged sphere with a particular choice of the electric field intensity and one of the gravitational potentials. The condition of pressure isotropy is reduced to a linear, second order differential equation which can be solved in general. Consequently we can find exact solutions to the Einstein Maxwell field equations corresponding to a static spherically symmetric gravitational potential in terms of hypergeometric functions. It is possible to find exact solutions which can be written explicitly in terms of elementary functions, namely polynomials and product of polynomials and algebraic functions. Uncharged solutions are regainable with our choice of electric field intensity; in particular we generate the Einstein universe for particular parameter values.
Charging Capacitors According to Maxwell's Equations: Impossible
Funaro, Daniele
2014-01-01
The charge of an ideal parallel capacitor leads to the resolution of the wave equation for the electric field with prescribed initial conditions and boundary constraints. Independently of the capacitor's shape and the applied voltage, none of the corresponding solutions is compatible with the full set of Maxwell's equations. The paradoxical situation persists even by weakening boundary conditions, resulting in the impossibility to describe a trivial phenomenon such as the capacitor's charging...
Directory of Open Access Journals (Sweden)
Héctor Torres-Silva
2008-11-01
Full Text Available This work deals with the problem of the construction of the Lagrange functional for an electromagnetic field. The generalised Maxwell equations for an electromagnetic field in free space are introduced. The main idea relies on the change of Lagrange function under the integral action. Usually, the Lagrange functional which describes the electromagnetic field is built with the quadrate of the electromagnetic field tensor . Such a quadrate term is the reason, from a mathematical point of view, for the linear form of the Maxwell equations in free space. The author does not make this assumption and nonlinear Maxwell equations are obtained. New material parameters of free space are established. The equations obtained are quite similar to the well-known Maxwell equations. The energy tensor of the electromagnetic field from a chiral approach to the Born Infeld Lagrangian is discussed in connection with the cosmological constant.Se aborda el problema de la construcción de la funcional de Lagrange de un campo electromagnético. Se introducen las ecuaciones generalizadas de Maxwell de un campo electromagnético en el espacio libre. La idea principal se basa en el cambio de función de Lagrange en virtud de la acción integral. Por lo general, la funcional de lagrange, que describe el campo electromagnético, se construye con el cuadrado del tensor de campo electromagnético. Ese término cuadrático es la razón, desde un punto de vista matemático, de la forma lineal de las ecuaciones de Maxwell en el espacio libre. Se obtienen las ecuaciones no lineales de Maxwell sin considerar esta suposición. Las ecuaciones de Maxwell obtenidas son bastante similares a las conocidas ecuaciones de Maxwell. Se analiza el tensor de energía del campo electromagnético en un enfoque quiral de la Lagrangiana de Born Infeld en relación con la constante cosmológica.
Maxwell: A new vision of the world
Maystre, Daniel
2014-05-01
The paper outlines the crucial contributions of James Clerk Maxwell to Physics and more generally to our vision of the world. He achieved 150 years ago a synthesis of the pioneering works in magnetostatics, electrostatics, induction and, by introducing the notion of displacement current, gave birth to Electromagnetics. Then, he deduced the existence of electromagnetic waves and identified light as one of them. Maxwell equations deeply changed a Newtonian conception of the world based on particle interactions by pointing out the vital role of waves in physics. This new conception had a strong influence on the development of quantum physics. Finally, the invariance of light velocity in Galilean frames led to Lorentz transformations, a key step toward the theory of relativity. Par ailleurs, les équations de Maxwell ont profondément changé une conception du monde newtonienne basée sur l'interaction entre particules en révélant le rôle essentiel des ondes en physique, ce qui eut une influence déterminante sur le développement de la physique quantique. Enfin, l'invariance de la vitesse de la lumière dans les repères galiléens a entraîné la découverte des transformations de Lorentz, une étape capitale vers la théorie de la relativité.
Directory of Open Access Journals (Sweden)
Lindomar Guimarães Oliveira
2015-06-01
Full Text Available OBJECTIVE: This open, randomized and blinded parallel-group multicenter study evaluated the efficacy of Actonel(r (35 mg plus calcium/vitamin D versus calcium/vitamin D alone for preserving bone mineral density (BMD in postmenopausal women with Colles fractures.METHODS: Patients with a Colles fracture for seven days were randomized to receive either Actonel(r (35 mg once a week plus calcium/vitamin D (ACD group or calcium/vitamin D alone (CD group. The patients were evaluated after 90 and 180 days of treatment.RESULTS: 59 ACD patients and 56 CD patients completed all the evaluations. At the end of the study, the BMD of the radius at the fracture location showed a negative change in the CD group (32.8%. The loss of BMD in the ACD group (20.8% was slightly less than that in the CD group. There was a difference in the proportions of patients with BMD losses at the end of the study period in the two treatment groups, in favor of the ACD group, although this was not statistically significant. There was no significant difference in radiological identification of callus formation between the treatment groups. In the majority of the patients, the callus could be radiologically identified after 90 days.CONCLUSION: Postmenopausal women with Colles fractures who received risedronate sodium plus calcium/vitamin D did not show any significant difference in BMD loss in forearm fractures, in comparison with those who received calcium/vitamin D alone. Risedronate presented a tendency toward a protective effect regarding BMD loss due to immobilization. The time taken for fracture consolidation to be achieved was unaffected.
Oliveira, Lindomar Guimarães; Eis, Sérgio Ragi; Neto, Henrique Mota; de Moraes, Frederico Barra; Pires, Luiz Antônio Silveira Simões; Vasconcelos, José Wanderley
2015-01-01
This open, randomized and blinded parallel-group multicenter study evaluated the efficacy of Actonel(®) (35 mg) plus calcium/vitamin D versus calcium/vitamin D alone for preserving bone mineral density (BMD) in postmenopausal women with Colles fractures. Patients with a Colles fracture for seven days were randomized to receive either Actonel(®) (35 mg) once a week plus calcium/vitamin D (ACD group) or calcium/vitamin D alone (CD group). The patients were evaluated after 90 and 180 days of treatment. 59 ACD patients and 56 CD patients completed all the evaluations. At the end of the study, the BMD of the radius at the fracture location showed a negative change in the CD group (32.8%). The loss of BMD in the ACD group (20.8%) was slightly less than that in the CD group. There was a difference in the proportions of patients with BMD losses at the end of the study period in the two treatment groups, in favor of the ACD group, although this was not statistically significant. There was no significant difference in radiological identification of callus formation between the treatment groups. In the majority of the patients, the callus could be radiologically identified after 90 days. Postmenopausal women with Colles fractures who received risedronate sodium plus calcium/vitamin D did not show any significant difference in BMD loss in forearm fractures, in comparison with those who received calcium/vitamin D alone. Risedronate presented a tendency toward a protective effect regarding BMD loss due to immobilization. The time taken for fracture consolidation to be achieved was unaffected.
Electromagnetic Unification: 150th Anniversary of Maxwell's Equations
Beléndez Vázquez, Augusto
2014-01-01
This article, published in Mètode is recalled that in 2015 the sesquicentennial of the Maxwell equations is celebrated. In 1865 Maxwell published an article entitled "A dynamical theory of the electromagnetic field" containing the Maxwell equations, the theoretical prediction of the existence of electromagnetic waves and electromagnetic theory of light. The article refers to Oersted, Ampere and Faraday, who laid the foundations of modern electromagnetism in the first third of the nineteenth c...
Maxwell's equations and their consequences elementary electromagnetic theory
Chirgwin, B H; Kilmister, C W 0
2013-01-01
Elementary Electromagnetic Theory Volume 3: Maxwell's Equations and their Consequences is the third of three volumes that intend to cover electromagnetism and its potential theory. The third volume considers the implications of Maxwell's equations, such as electromagnetic radiation in simple cases, and its relation between Maxwell's equation and the Lorenz transformation. Included in this volume are chapters 11-14, which contain an in-depth discussion of the following topics: Electromagnetic Waves The Lorentz Invariance of Maxwell's Equation Radiation Motion of Charged Particles Intended
International Nuclear Information System (INIS)
Anon.
1979-01-01
Earlier this year saw the centenary of the birth of Albert Einstein. It is highly apt that 1979, which has been marked by further consolidation of the unified theory of weak and electromagnetic interactions and its recognition in the award of the Nobel Prize to Glashow, Salam and Weinberg, is also the centenary of the death of the great Scottish physicist who first formulated a unified theory of electric and magnetic fields. We are grateful to Abdus Salam for drawing our attention to the Maxwell anniversary
FDTD for Hydrodynamic Electron Fluid Maxwell Equations
Directory of Open Access Journals (Sweden)
Yingxue Zhao
2015-05-01
Full Text Available In this work, we develop a numerical method for solving the three dimensional hydrodynamic electron fluid Maxwell equations that describe the electron gas dynamics driven by an external electromagnetic wave excitation. Our numerical approach is based on the Finite-Difference Time-Domain (FDTD method for solving the Maxwell’s equations and an explicit central finite difference method for solving the hydrodynamic electron fluid equations containing both electron density and current equations. Numerical results show good agreement with the experiment of studying the second-harmonic generation (SHG from metallic split-ring resonator (SRR.
Exact Internal Controllability of Maxwell's Equations
International Nuclear Information System (INIS)
Zhang, X.
2000-01-01
In this paper we obtain two exact internal controllability results of Maxwell's equations in a general region by using multiplier techniques. The first one is exact controllability in a short time, in which we obtain the 'optimal' (observability) estimates when the location and the shape of the controller is fixed. What happens if we allow the controller to change? Under some conditions, we show that by doing that the system can be exactly controllable within any given time duration, which is our second exact controllability result
Contra la corriente: el experimento de George Bataille y el Collège de Sociologie
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Victoria D'hers
2014-12-01
Full Text Available Fernando Giobellina Brumana se propone recorrer el camino seguido por el Collège de Sociologie, y para presentarlo parte de su descripción como contracara oscura de L'Année Sociologique, refiriendo detalladamente al rol de George Bataille, Roger Caillois y Michel Leiris. Para comenzar este recorrido, lo más distintivo es la errática herencia del Collège en relación con la escuela que la revista de Emile Durkheim inició. El autor lleva a cabo una reconstrucción rigurosa de fuentes y, conceptualmente, trabaja el uso de lo impuro y lo abyecto, anclándolo en el ejemplo específico de este grupo, esclareciendo paulatinamente las nociones en tensión con el punto de vista de L'Année. En su segunda parte, se guiará por la obra de Hertz para delinear un antecedente a estas experiencias. Con todo, este libro parece ser un texto especializado, una conversación con quien ya sabe. Pero a la vez mantiene un estilo íntimo, donde el autor se reconoce en los personajes y da su opinión sobre ellos.
Studio e recupero 3D della necropoli di Colle del Forno
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Roberto Gabrielli
2007-04-01
Full Text Available La Necropoli Sabina sita nel territorio di Colle del Forno, all’interno dell’Area della Ricerca del CNR RM1, ha rappresentato nel tempo, oltre ad una testimonianza di indubbio valore storico-archeologico, un’occasione ideale per poter sviluppare ed affinare tecniche avanzate di indagine del suolo e sottosuolo con metodi indiretti. Il progetto, nato grazie alla collaborazione interdisciplinare tra l’Istituto per le Tecnologie Applicate ai Beni Culturali e l’Istituto di Studi sulle Civiltà Italiche e del Mediterraneo Antico (CNR nella persona della Dott.ssa Paola Santoro, Responsabile archeologico, ha avuto come obiettivo l’indagine intensiva dell’altura di Colle del Forno attraverso prospezioni geofisiche, topografiche e di rilievo ad alta risoluzione congiunte alle indagini archeologiche dirette, al fine di definire l’occupazione della collina nell’evoluzione diacronica e storica in rapporto all’insediamento Sabino di Eretum
Generalized Maxwell equations and charge conservation censorship
Modanese, G.
2017-02-01
The Aharonov-Bohm electrodynamics is a generalization of Maxwell theory with reduced gauge invariance. It allows to couple the electromagnetic field to a charge which is not locally conserved, and has an additional degree of freedom, the scalar field S = ∂αAα, usually interpreted as a longitudinal wave component. By reformulating the theory in a compact Lagrangian formalism, we are able to eliminate S explicitly from the dynamics and we obtain generalized Maxwell equation with interesting properties: they give ∂μFμν as the (conserved) sum of the (possibly non-conserved) physical current density jν, and a “secondary” current density iν which is a nonlocal function of jν. This implies that any non-conservation of jν is effectively “censored” by the observable field Fμν, and yet it may have real physical consequences. We give examples of stationary solutions which display these properties. Possible applications are to systems where local charge conservation is violated due to anomalies of the Adler-Bell-Jackiw (ABJ) kind or to macroscopic quantum tunnelling with currents which do not satisfy a local continuity equation.
Comparing Teaching Approaches About Maxwell's Displacement Current
Karam, Ricardo; Coimbra, Debora; Pietrocola, Maurício
2014-08-01
Due to its fundamental role for the consolidation of Maxwell's equations, the displacement current is one of the most important topics of any introductory course on electromagnetism. Moreover, this episode is widely used by historians and philosophers of science as a case study to investigate several issues (e.g. the theory-experiment relationship). Despite the consensus among physics educators concerning the relevance of the topic, there are many possible ways to interpret and justify the need for the displacement current term. With the goal of understanding the didactical transposition of this topic more deeply, we investigate three of its domains: (1) The historical development of Maxwell's reasoning; (2) Different approaches to justify the term insertion in physics textbooks; and (3) Four lectures devoted to introduce the topic in undergraduate level given by four different professors. By reflecting on the differences between these three domains, significant evidence for the knowledge transformation caused by the didactization of this episode is provided. The main purpose of this comparative analysis is to assist physics educators in developing an epistemological surveillance regarding the teaching and learning of the displacement current.
2013 Elections to Staff Council
Staff Association
2013-01-01
Elections Timetable Starting with Echo of 16 September, posters, etc. call for applications Monday 21 October, at noon closing date for receipt of the applications Monday 28 October, at noon start date for voting Monday 11 November, at noon closing date for voting Monday 18 and Monday 25 November, publication of the results in Echo Tuesday 19 November Staff Association Assizes Tuesday 3 December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure is monitored by the Election Committee, which is also in charge of announcing the results in Echo on 18 and 25 November. n its meeting on 11 September 2013, the Electoral Commission decided on the following distribution of seats in colleges O.1 to O.6: Sectors Departments Career paths AA – A – B – C – D Career paths E – F – G – H Accelerators and Technology BE TE EN Electoral colle...
Staff Association
2014-01-01
Remove of the staff association office The Staff Association offices are going to be renovated during the coming four months, February to May 2014. The physical move from our current premises 64/R-002 to our temporary office in 510/R-010 will take place on Friday January 31st, so the Secretariat will be closed on that day. Hence, from Monday February 3rd until the end of May 2014 the Staff Association Secretariat will be located in 510/R-010 (entrance just across the CERN Printshop).
Maxwells ligninger og de elektromagnetiske bølger
DEFF Research Database (Denmark)
Mandrup, Lars
2000-01-01
Dette kompendie i Videregående Elektrodynamik omhandler Maxwells ligninger på differential¬form og disses anvendelse til at beskrive de elektromagnetiske bølger og deres egenskaber. Udgangspunktet for kompendiet er Maxwells ligninger på integralform, som det forudsættes, at læseren er bekendt med...
Incompressible Einstein–Maxwell fluids with specified electric fields
Indian Academy of Sciences (India)
isotropic pressures. This highlights the necessity of studying the criteria for physical admissability of gravitating spheres in general relativity which are solutions to the Einstein–Maxwell equations. Keywords. Einstein–Maxwell equations; relativistic astrophysics; charged fluid spheres. PACS Nos 04.20.Jb; 04.40.Dg; 04.40.Nr.
Maxwell Equations and the Redundant Gauge Degree of Freedom
Wong, Chun Wa
2009-01-01
On transformation to the Fourier space (k,[omega]), the partial differential Maxwell equations simplify to algebraic equations, and the Helmholtz theorem of vector calculus reduces to vector algebraic projections. Maxwell equations and their solutions can then be separated readily into longitudinal and transverse components relative to the…
Chaotic dynamics in the Maxwell-Bloch equations
International Nuclear Information System (INIS)
Holm, D.D.; Kovacic, G.
1992-01-01
In the slowly varying envelope approximation and the rotating wave approximation for the Maxwell-Bloch equations, we describe how the presence of a small-amplitude probe laser in an excited, two-level, resonant medium leads to homoclinic chaos in the laser-matter dynamics. We also describe a derivation of the Maxwell-Bloch equations from an action principle
Incompressible Einstein–Maxwell fluids with specified electric fields
Indian Academy of Sciences (India)
strated that uniform density spheres with constant electric field intensity are not realizable with isotropic pressures. This highlights the necessity of studying the criteria for physical admissability of gravitating spheres in general relativity which are solutions to the Einstein–Maxwell equations. Keywords. Einstein–Maxwell ...
An Eulerian gyrokinetic-Maxwell solver
Candy, J
2003-01-01
In this report we present a time-explicit, Eulerian numerical scheme for the solution of the nonlinear gyrokinetic-Maxwell equations. The treatment of electrons is fully drift-kinetic, transverse electromagnetic fluctuations are included, and profile variation is allowed over an arbitrary radial annulus. The code, gyro, is benchmarked against analytic theory, linear eigenmode codes, and nonlinear electrostatic gyrokinetic particle-in-cell codes. We have attempted preliminary finite-beta calculations in the range beta/beta sub c sub r sub i sub t =[0.0,0.5] for a reference discharge. Detailed diagnostic data is presented for these simulations, along with a number of caveats which reflect the uncharted nature of the parameter regime.
An extended formulation of Maxwell's equations
International Nuclear Information System (INIS)
Lehnert, B.
1985-10-01
An extended Lorentz invariant formulation of Maxwell's equations is presented which both includes time dependent and steady-state solutions. In this approach the charge and current densities are treated as intrinsic properties of the electromagnetic field itself, in vacuo. Two main results follow from such an approach. First, a longitudinal electric wave is predicted to propagate in vacuo. Second, an axially symmetric steady state can be outlined in which 'self-confined' electromagnetic radiation circulates in closed orbits around the axis of symmetry. For this state values are obtained of the charge, the spin, and the product between magnetic moment and mass which are of the same order of magnitude as those observed for some elementary particles such as the proton and electron. Consequently, this may provide certain areas of conventional elementary particle analysis with some complementary ideas. Whether the predicted new phenomena also correspond to physical realities is so far an open question which requires further investigation. With 6 refs. (Author)
The Life of James Clerk Maxwell
Campbell, Lewis; Garnett, William
2010-06-01
Preface; Part I. Biographical Outline: 1. Birth and parentage; 2. Glenlair - childhood, 1831-1841; 3. Boyhood, 1841-1844; 4. Adolescence, 1844-1847; 5. Opening manhood, 1847-1850; 6. Undergraduate life at Cambridge, 1850-1854; 7. Bachelor-scholar and fellow of Trinity, 1854-1856; 8. Essays at Cambridge, 1853-1856; 9. Death of his father. Professorship at Aberdeen, 1856-1857; 10. Aberdeen. Marriage, 1857-1860; 11. King's College, London. Glenair, 1860-1870; 12. Cambridge, 1871-1879; 13. Illness and death, 1879; 14. Last essays at Cambridge; Part II. Contributions to Science: 1. Experiments on colour vision, and other contributions to optics; 2. Investigations respecting elastic solids; 3. Pure geometry; 4. Mechanics; 5. Saturn's rings; 6. Faraday's lines of force, and Maxwell's theory of the electromagnetic field; 7. Molecular physics; Part III. Poems: 1. Juvenile verses and translations; 2. Occasional pieces; 3. Serio-comic verse; Index.
Incompressible Navier-Stokes equation from Einstein-Maxwell and Gauss-Bonnet-Maxwell theories
International Nuclear Information System (INIS)
Niu Chao; Tian Yu; Wu Xiaoning; Ling Yi
2012-01-01
The dual fluid description for a general cutoff surface at radius r=r c outside the horizon in the charged AdS black brane bulk space-time is investigated, first in the Einstein-Maxwell theory. Under the non-relativistic long-wavelength expansion with parameter ε, the coupled Einstein-Maxwell equations are solved up to O(ε 2 ). The incompressible Navier-Stokes equation with external force density is obtained as the constraint equation at the cutoff surface. For non-extremal black brane, the viscosity of the dual fluid is determined by the regularity of the metric fluctuation at the horizon, whose ratio to entropy density η/s is independent of both the cutoff r c and the black brane charge. Then, we extend our discussion to the Gauss-Bonnet-Maxwell case, where the incompressible Navier-Stokes equation with external force density is also obtained at a general cutoff surface. In this case, it turns out that the ratio η/s is independent of the cutoff r c but dependent on the charge density of the black brane.
Bedrock geologic and structural map through the western Candor Colles region of Mars
Okubo, Chris H.
2014-01-01
The Candor Colles are a population of low, conical hills along the southeast flank of Ceti Mensa, in west Candor Chasma, within the Valles Marineris system of Mars (fig. 1). Ceti Mensa and the adjacent Candor Mensa are mounds of layered sedimentary deposits and are the most prominent landforms within west Candor Chasma. Prior to the arrival of the Mars Reconnaissance Orbiter (MRO) in orbit around Mars in 2006 (Zurek and Smrekar, 2007), geologic maps of the area utilized the relatively low resolution Viking Orbiter photomosaics (20–150 m/pixel). Geologic maps covering west Candor Chasma were created at scales of 1:15,000,000 for the western equatorial region of Mars (Scott and Tanaka, 1986), 1:2,000,000 for the Valles Marineris region (Witbeck and others, 1991), and 1:500,000 for the far eastern part of west Candor Chasma (Mars Transverse Mercator quadrangle–05072; Lucchitta, 1999).
La collégiale de Saint-Bonnet-le-Château (Loire
Directory of Open Access Journals (Sweden)
Bernard Ducouret
2012-04-01
Full Text Available La collégiale de Saint-Bonnet-le-Château est principalement connue pour les peintures murales du XVe siècle qui décorent sa chapelle basse, dont une partie est reproduite au musée des Monuments français, et, à un moindre degré, pour sa bibliothèque qui conserve de nombreux incunables. Son architecture, plus ignorée, n'en est pas moins digne d'intérêt. Nous ne présenterons pas ici l'ensemble de l'édifice, négligeant des éléments remarquables comme le porche sud (cf. plan, au-dessous de la sacr...
Stel, Jan H.
1976-01-01
The author supposes that the fossil content of thin carbonate units in the Upper La Vid shales (Lower Devonian) of Colle was influenced by heavy storms like hurricanes. Apart from microplankton (Cramer, 1964) no fossils are found in the shales. Together with the very well developed fissility of the
Carney, Martin J; Matatov, Tim; Freeman, Matthew; Miller, John; Vemula, Rahul; Schuster, Jason; Dancisak, Michael; Lindsey, John; Rae, Guenevere
2017-06-01
The medial thighplasty is a procedure where patients may attain superior mobility, hygiene, and cosmesis. Most surgeons use attachment of the superficial fascial system (SFS) of the thigh flap to the Colles fascia, whereas others attach the SFS to the pubic ramus periosteum. Because of a high complication profile, we aim to elucidate the clinical, biomechanical, and anatomic qualities of the Colles fascia versus the pubic ramus periosteum. We performed a 17-year retrospective review documenting clinical complications, a biomechanical analysis of sutures placed in different tissue layers of the thigh, and a histologic analysis surrounding the ischiopubic ramus. Separate suture pull-out strength testing was conducted on cadaveric tissue using an Admet MTEST Quattro with no. 1 Vicryl suture and tissue grips at a displacement rate of 2.12 mm/s. Simultaneous displacement and force were acquired at 100 Hz and with measurements obtained at regular intervals between the pubic symphysis and the ischial tuberosity in both the Colles fascia and the deeper periosteal layers of the thigh. A histologic analysis was performed at 3 points along the ischiopubic ramus using paraffin-embedded large mount tissue sections stained with hematoxylin, eosin, and Gomori trichrome. Thirty-nine patients underwent medial thighplasty with a 46.16% complication rate. Suture pull-out force of the suspected superficial Colles fascia sites was, on average, 72.8% less than values from the deeper periosteum tissue. Anchor points in the Colles fascia elongated 17.4% further before failure than those in the periosteum. There was noticeable variability between anchor points and across samples. The histologic sections suggest that the Colles fascia from the different regions of the ischiopubic ramus varies considerably in both continuity and collagen fiber content with no discernible pattern. The periosteal and muscular fascial layers were more continuous histologically with direct attachments into the
Information Systems and Corporate Memory: design for staff turn-over
Colin Sharp; Neil Lewis
1993-01-01
The "information age" is reliant upon the information skill-base of people and the storage and access of complete data. Staff turn-over and "down-sizing" as well as the rate of organisational change places increased pressure on the designers of corporate information systems to keep up with the organizational demands. Especially relevant are the "soft" aspects of the corporate information needs of organizations. The term "corporate memory" is introduced to explain the relatively informal colle...
High-order finite element approximations of the Maxwell equations
Sarmany, D.
2010-01-01
This thesis discusses numerical approximations of electromagnetic wave propagation, which is mathematically described by the Maxwell equations. These equations are typically either formulated as integral equations or as (partial) differential equations. Throughout this thesis, the numerical
Distribución de probabilidad de Maxwell transmutada
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Yuri A. Iriarte
2014-12-01
Full Text Available En este artículo introducimos una extensión de la distribución de probabilidad de Maxwell. Esta extensión se genera utilizando el mapa de transmutación de rango cuadrático, estudiado por Shaw y Buckley en [13], considerando como función base la función de distribución acumulada del modelo de Maxwell. Estudiamos propiedades probabilísticas, realizamos inferencia estadística y estudiamos una aplicación con datos reales Abstract. In this paper we introduce an extension of the Maxwell probability distribution. This extension is generated using the quadratic rank transmutation map studied by Shaw and Buckley in [13], considering as the basis function the cumulative distribution function of the Maxwell model. We study probabilistic properties, we perform statistical inference and study an application with real data.
Maxwell-Garnett effective medium theory: Quantum nonlocal effects
Energy Technology Data Exchange (ETDEWEB)
Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Engineering Physics, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of)
2015-04-15
We develop the Maxwell-Garnett theory for the effective medium approximation of composite materials with metallic nanoparticles by taking into account the quantum spatial dispersion effects in dielectric response of nanoparticles. We derive a quantum nonlocal generalization of the standard Maxwell-Garnett formula, by means the linearized quantum hydrodynamic theory in conjunction with the Poisson equation as well as the appropriate additional quantum boundary conditions.
Mes chers collègues, les moines, ou le partage de l’ignorance
Directory of Open Access Journals (Sweden)
Laurence Caillet
2009-03-01
Full Text Available Mes chers collègues, les moines, ou le partage de l’ignorance. Aucun statut ne m’a autant étonnée que celui de collègue qui me fut conféré par les moines du Grand monastère de l’Est, à Nara. Après avoir testé mes connaissances en matière de rituel, ces moines fort savants manifestèrent en effet, avec ostentation, leur ignorance. Pointant pour moi des détails liturgiques qu’ils tenaient pour incompréhensibles, ils prirent un plaisir évident à bavarder histoire et théologie, comme si je pouvais apporter quoi que ce soit. Cette mise en scène du caractère incompréhensible du rituel soulignait le caractère ineffable de cérémonies jadis accomplies au ciel par des entités supérieures. Je fournissais prétexte à décrire la vanité de l’érudition face à l’accomplissement des mystères et aussi l’importance de cette érudition pour renouer avec un sens originel irrémédiablement inconnaissable.My dear colleagues the monks, or the sharing of ignorance. No status has ever surprised me as much as that of “colleague” conferred on me by the monks of the Great Eastern Monastery of Nara. After testing my knowledge of ritual, these very learned monks made great show of their ignorance. Drawing my attention to liturgical details that they held to be incomprehensible, they took obvious pleasure in chatting about history and theology, as if I were capable of making the slightest contribution. This staging of the impenetrable nature of the ritual highlighted the ineffable character of the ceremonies performed in heaven long ago by superior beings. I provided a convenient pretext for describing the vanity of erudition in the face of the accomplishment of the mysteries, and also the importance of this erudition for renewing an original, irreparably unknowable meaning.
Hopkins in the Age of Maxwell Hopkins à l’époque de Maxwell
Directory of Open Access Journals (Sweden)
René Gallet
2005-01-01
Full Text Available Lorsque l’on veut situer l’œuvre de Hopkins dans son contexte scientifique, on a l’habitude de le faire uniquement par rapport au débat évolutionniste, ou même darwinien, comme dans l’ouvrage de référence de T. Zaniello, Hopkins in the Age of Darwin. Ceci présuppose une vision sélective de ce contexte où figure notamment une autre grande révolution scientifique, dans le domaine de la physique fondamentale. Le représentant le plus éminent en est J. C. Maxwell, chaînon essentiel entre Newton et Einstein. Dans ses textes, Hopkins lui-même s’est intéressé surtout à cette autre révolution scientifique, allant jusqu’à commencer un livre critique envers Light, ouvrage de Tait, physicien de renom et ami de Maxwell. Hopkins s’en prend plus à l’épistémologie idéaliste illustrée, selon le poète, par Tait, qu’à la pensée davantage matérialiste d’un Tyndall. La raison en est sans doute son attachement à un réalisme philosophique dont dépend la notion d’ « inscape ».
Maxwell's demon. (I) A thermodynamic exorcism
Gyftopoulos, Elias P.
2002-05-01
It is shown that Maxwell's demon is unable to accomplish his task not because of considerations related to irreversibility, acquisition of information, and computers and erasure of information but because of limitations imposed by the properties of the system on which he is asked to perform his demonic manipulations. The limitations emerge from two recent but related developments of which Maxwell was completely unaware. One is an exposition of thermodynamics as a nonstatistical theory, valid for all systems, both large and small, including a system with only one degree of (translational) freedom, and for all states, both thermodynamic or stable equilibrium states and states that are not thermodynamic equilibrium, including states encountered in mechanics. In this theory, entropy is proven to be a nondestructible, nonstatistical property of any state in the same sense that inertial mass is a nonstatistical property of any state. In Part I, the demon is shown to be incapable of accomplishing his task because this would be equivalent either to reducing the nondestructible and nonstatistical entropy of air in a container without compensation by any other system, including himself, or to extracting only energy from the air under conditions that require the extraction of both energy and entropy. The second development is a unified, quantum-theoretic interpretation of mechanics and the thermodynamics just cited. In this theory: (a) the quantum-theoretic probabilities of measurement results are represented by a density operator ρ that corresponds to a homogeneous ensemble of identical systems, identically prepared; homogeneous is an ensemble in which every member is described by the same density operator ρ as any other member, that is, the ensemble is not a statistical mixture of projectors (wave functions); said differently, experimentally (as opposed to algebraically) the homogeneous ensemble cannot be decomposed into mixtures either of pure states or other mixtures
Maxwell fields and shear-free null geodesic congruences
International Nuclear Information System (INIS)
Newman, Ezra T
2004-01-01
We study and report on the class of vacuum Maxwell fields in Minkowski space that possess a non-degenerate, diverging, principal null vector field (null eigenvector field of the Maxwell tensor) that is tangent to a shear-free null geodesics congruence. These congruences can be either surface forming (the tangent vectors being proportional to gradients) or not, i.e., the twisting congruences. In the non-twisting case, the associated Maxwell fields are precisely the Lienard-Wiechert fields, i.e., those Maxwell fields arising from an electric monopole moving on an arbitrary worldline. The null geodesic congruence is given by the generators of the light-cones with apex on the worldline. The twisting case is much richer, more interesting and far more complicated. In a twisting subcase, where our main interests lie, the following strange interpretation can be given. If we allow the real Minkowski space to be complexified so that the real Minkowski coordinates x a take complex values, i.e., x a → z a = x a + iy a with complex metric g η ab dz a dz b , the real vacuum Maxwell equations can be extended into the complex space and rewritten as curl W=i W radical, div W=0 with W=E+iB. This subcase of Maxwell fields can then be extended into the complex space so as to have as source, a complex analytic worldline, i.e., to now become complex Lienard-Wiechart fields. When viewed as real fields on the real Minkowski space (z a = x a ), they possess a real principal null vector that is shear-free but twisting and diverging. The twist is a measure of how far the complex worldline is from the real 'slice'. Most Maxwell fields in this subcase are asymptotically flat with a time-varying set of electric and magnetic moments, all depending on the complex displacements and the complex velocities
Stochastic Levy Divergence and Maxwell's Equations
Directory of Open Access Journals (Sweden)
B. O. Volkov
2015-01-01
Full Text Available One of the main reasons for interest in the Levy Laplacian and its analogues such as Levy d'Alembertian is a connection of these operators with gauge fields. The theorem proved by Accardi, Gibillisco and Volovich stated that a connection in a bundle over a Euclidean space or over a Minkowski space is a solution of the Yang-Mills equations if and only if the corresponding parallel transport to the connection is a solution of the Laplace equation for the Levy Laplacian or of the d'Alembert equation for the Levy d'Alembertian respectively (see [5, 6]. There are two approaches to define Levy type operators, both of which date back to the original works of Levy [7]. The first is that the Levy Laplacian (or Levy d'Alembertian is defined as an integral functional generated by a special form of the second derivative. This approach is used in the works [5, 6], as well as in the paper [8] of Leandre and Volovich, where stochastic Levy-Laplacian is discussed. Another approach to the Levy Laplacian is defining it as the Cesaro mean of second order derivatives along the family of vectors, which is an orthonormal basis in the Hilbert space. This definition of the Levy Laplacian is used for the description of solutions of the Yang-Mills equations in the paper [10].The present work shows that the definitions of the Levy Laplacian and the Levy d'Alembertian based on Cesaro averaging of the second order directional derivatives can be transferred to the stochastic case. In the article the values of these operators on a stochastic parallel transport associated with a connection (vector potential are found. In this case, unlike the deterministic case and the stochastic case of Levy Laplacian from [8], these values are not equal to zero if the vector potential corresponding to the stochastic parallel transport is a solution of the Maxwell's equations. As a result, two approaches to definition of the Levy Laplacian in the stochastic case give different operators. This
James Clerk Maxwell perspectives on his life and work
McCartney, Mark; Whitaker, Andrew
2014-01-01
James Clerk Maxwell (1831-1879) had a relatively brief, but remarkable life, lived in his beloved rural home of Glenlair, and variously in Edinburgh, Aberdeen, London and Cambridge. His scholarship also ranged wide - covering all the major aspects of Victorian natural philosophy. He was one of the most important mathematical physicists of all time, coming only after Newton and Einstein. In scientific terms his immortality is enshrined in electromagnetism and Maxwell's equations, but as this book shows, there was much more to Maxwell than electromagnetism, both in terms of his science and his wider life. Maxwell's life and contributions to science are so rich that they demand the expertise of a range of academics - physicists, mathematicians, and historians of science and literature - to do him justice. The various chapters will enable Maxwell to be seen from a range of perspectives. Chapters 1 to 4 deal with wider aspects of his life in time and place, at Aberdeen, King's College London and the Cavendish Labo...
Energy Technology Data Exchange (ETDEWEB)
Fochesato, Ch. [CEA Bruyeres-le-Chatel, Dept. de Conception et Simulation des Armes, Service Simulation des Amorces, Lab. Logiciels de Simulation, 91 (France); Bouche, D. [CEA Bruyeres-le-Chatel, Dept. de Physique Theorique et Appliquee, Lab. de Recherche Conventionne, Centre de Mathematiques et Leurs Applications, 91 (France)
2007-07-01
The numerical solution of Maxwell equations is a challenging task. Moreover, the range of applications is very wide: microwave devices, diffraction, to cite a few. As a result, a number of methods have been proposed since the sixties. However, among all these methods, none has proved to be free of drawbacks. The finite difference scheme proposed by Yee in 1966, is well suited for Maxwell equations. However, it only works on cubical mesh. As a result, the boundaries of complex objects are not properly handled by the scheme. When classical nodal finite elements are used, spurious modes appear, which spoil the results of simulations. Edge elements overcome this problem, at the price of rather complex implementation, and computationally intensive simulations. Finite volume methods, either generalizing Yee scheme to a wider class of meshes, or applying to Maxwell equations methods initially used in the field of hyperbolic systems of conservation laws, are also used. Lastly, 'Discontinuous Galerkin' methods, generalizing to arbitrary order of accuracy finite volume methods, have recently been applied to Maxwell equations. In this report, we more specifically focus on the coupling of a Maxwell solver to a PIC (Particle-in-cell) method. We analyze advantages and drawbacks of the most widely used methods: accuracy, robustness, sensitivity to numerical artefacts, efficiency, user judgment. (authors)
van Walraven, Carl
2018-04-01
Misclassification bias can result from the incorrect assignment of disease status using inaccurate diagnostic codes in health administrative data. This study quantified misclassification bias in the study of Colles' fracture. Colles' fracture status was determined in all patients >50 years old seen in the emergency room at a single teaching hospital between 2006 and 2014 by manually reviewing all forearm radiographs. This data set was linked to population-based data capturing all emergency room visits. Reference disease prevalence and its association with covariates were measured. A multivariate model using covariates derived from administrative data was used to impute Colles' fracture status and measure its prevalence and associations using bootstrapping methods. These values were compared with reference values to measure misclassification bias. This was repeated using diagnostic codes to determine Colles' fracture status. Five hundred eighteen thousand, seven hundred forty-four emergency visits were included with 3,538 (0.7%) having a Colles' fracture. Determining disease status using the diagnostic code (sensitivity 69.4%, positive predictive value 79.9%) resulted in significant underestimate of Colles' fracture prevalence (relative difference -13.3%) and biased associations with covariates. The Colles' fracture model accurately determined disease probability (c-statistic 98.9 [95% confidence interval {CI} 98.7-99.1], calibration slope 1.009 [95% CI 1.004-1.013], Nagelkerke's R 2 0.71 [95% CI 0.70-0.72]). Using disease probability estimates from this model, bootstrap imputation (BI) resulted in minimal misclassification bias (relative difference in disease prevalence -0.01%). The statistical significance of the association between Colles' fracture and age was accurate in 32.4% and 70.4% of samples when using the code or BI, respectively. Misclassification bias in estimating disease prevalence and its associations can be minimized with BI using accurate disease
Ultramafic intrusion triggers hydrothermal explosions at Colle Fabbri (Spoleto, Umbria), Italy
Stoppa, Francesco; Rosatelli, Gianluigi
2009-10-01
The eroded Colle Fabbri volcano comprises intrusive and extrusive rocks which cover an area of about 10,000 m 2 in the Umbria region, Central Italy. The outcrop is located at the SW boundary of the Umbria Valley Graben (Umbria Region) on an N140 normal fault inside the Intramountain Ultra-Alkaline Province of carbonatite and melilitite rocks of central-southern Italy. A field survey of the outcrop allowed a reconstruction of igneous activity events of this unusual small-scale volcano. It is younger than 0.7 m.y. and rests on Lower Pleistocene conglomerates with intercalated clay beds. A palaeosoil marks the base of the volcanic sequence. It follows several metres of extrusive breccias composed of fragments of thermometamorphosed clay and travertine. Key features of these breccias are mud shells on blocks, plastic mud lumps, slumps, and mechanical injection from one layer into another, as well as plastic and vesiculated, micro-brecciated matrix. The breccias are cemented by a variety of silicate, sulphate, and sulphate-carbonate minerals deposited by intense hydrothermal circulation. The breccias are related to phreatic explosions triggered by the eruption of a superficial hydrothermal system. Up to 1 m thick sill and a dykelet swarm intrude the breccias. In the southern part of the outcrop there is a plug of melilitolitic composition which intrudes the breccias and deforms them upward. A variety of contact breccias is also scattered around the sill and the plug. In some places, hyaloclastite formed when melt invaded water pockets contained in the encasing rocks under hydrostatic pressure conditions. A thermal aureole, which moves up to 10 m away from the contact, is characterised by cordierite-trydimite association, thus indicating high-temperature (>>1000 °C) contact phenomena.
A Derivation of Maxwell Equations in Quaternion Space
Directory of Open Access Journals (Sweden)
Christianto V.
2010-04-01
Full Text Available Quaternion space and its respective Quaternion Relativity (it also may be called as Rotational Relativity has been defined in a number of papers, and it can be shown that this new theory is capable to describe relativistic motion in elegant and straightforward way. Nonetheless there are subsequent theoretical developments which remains an open question, for instance to derive Maxwell equations in Q-space. Therefore the purpose of the present paper is to derive a consistent description of Maxwell equations in Q-space. First we consider a simplified method similar to the Feynman's derivation of Maxwell equations from Lorentz force. And then we present another derivation method using Dirac decomposition, introduced by Gersten (1999. Further observation is of course recommended in order to refute or verify some implication of this proposition.
James Clerk Maxwell and the dynamics of astrophysical discs.
Ogilvie, Gordon I
2008-05-28
Maxwell's investigations into the stability of Saturn's rings provide one of the earliest analyses of the dynamics of astrophysical discs. Current research in planetary rings extends Maxwell's kinetic theory to treat dense granular gases of particles undergoing moderately frequent inelastic collisions. Rather than disrupting the rings, local instabilities may be responsible for generating their irregular radial structure. Accretion discs around black holes or compact stars consist of a plasma permeated by a tangled magnetic field and may be compared with laboratory fluids through an analogy that connects Maxwell's researches in electromagnetism and viscoelasticity. A common theme in this work is the appearance of a complex fluid with a dynamical constitutive equation relating the stress in the medium to the history of its deformation.
The scientific papers of James Clerk Maxwell, vol.I
Maxwell, James Clerk
2014-01-01
One of the greatest theoretical physicists of the 19th century, James Clerk Maxwell is best known for his studies of the electromagnetic field. The 101 scientific papers of this two-volume set, arranged chronologically, testify to Maxwell's profound scientific legacy and include the preliminary explorations that culminated in his most famous work, A Treatise on Electricity and Magnetism. One of the nineteenth century's most significant papers, "A Dynamical Theory of the Electromagnetic Field," appears here, along with similarly influential expositions of Maxwell's dynamical theory of gases. The author's extensive range of interests is well represented, from his discussions of color blindness and the composition of Saturn's rings to his essays on geometrical optics, ether, and protecting buildings from lightning. His less technical writings are featured as well, including items written for the Encyclopedia Britannica and Nature magazine, book reviews, and popular lectures. Striking in their originality, these ...
Maxwell-Chern-Simons theory with a boundary
Energy Technology Data Exchange (ETDEWEB)
Blasi, A; Maggiore, N; Magnoli, N [Dipartimento di Fisica, Universita di Genova-via Dodecaneso 33, I-16146 Genova (Italy); Storace, S, E-mail: alberto.blasi@ge.infn.g, E-mail: nicola.maggiore@ge.infn.i, E-mail: nicodemo.magnoli@ge.infn.i, E-mail: stefano.storace@nyu.ed [Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States)
2010-08-21
The Maxwell-Chern-Simons (MCS) theory with a planar boundary is considered. The boundary is introduced according to Symanzik's basic principles of locality and separability. A method of investigation is proposed, which, avoiding the straight computation of correlators, is appealing for situations where the computation of propagators, modified by the boundary, becomes quite complex. For the MCS theory, the outcome is that a unique solution exists, in the form of chiral conserved currents, satisfying a Kac-Moody algebra, whose central charge does not depend on the Maxwell term.
Variational principle for nonlinear gyrokinetic Vlasov--Maxwell equations
International Nuclear Information System (INIS)
Brizard, Alain J.
2000-01-01
A new variational principle for the nonlinear gyrokinetic Vlasov--Maxwell equations is presented. This Eulerian variational principle uses constrained variations for the gyrocenter Vlasov distribution in eight-dimensional extended phase space and turns out to be simpler than the Lagrangian variational principle recently presented by H. Sugama [Phys. Plasmas 7, 466 (2000)]. A local energy conservation law is then derived explicitly by the Noether method. In future work, this new variational principle will be used to derive self-consistent, nonlinear, low-frequency Vlasov--Maxwell bounce-gyrokinetic equations, in which the fast gyromotion and bounce-motion time scales have been eliminated
The Maxwell equations as a Bäcklund transformation
Directory of Open Access Journals (Sweden)
C. J. Papachristou
2015-07-01
Full Text Available Bäcklund transformations (BTs are a useful tool for integrating nonlinear partial differential equations (PDEs. However, the significance of BTs in linear problems should not be ignored. In fact, an important linear system of PDEs in Physics, namely, the Maxwell equations of Electromagnetism, may be viewed as a BT relating the wave equations for the electric and the magnetic field, these equations representing integrability conditions for solution of the Maxwell system. We examine the BT property of this system in detail, both for the vacuum case and for the case of a linear conducting medium.
The contributions of Faraday and Maxwell to electrical science
Tricker, R A R
1966-01-01
The Contributions of Faraday and Maxwell to Electrical Science deals with the development of electromagnetic theory following the establishment of the basis for the first law of circulation relating to the magnetic fields generated by steady currents. This book is organized into two parts encompassing nine chapters that specifically treat the provision of the basis for the second law of circulation, the law that deals with the induction of currents, which was predominantly the work of British physicists, Michael Faraday and James Clerk Maxwell. Part I highlights their life, career, and contri
2001-01-01
The English National Programme, part of the Lycée International de Ferney-Voltaire (France) needs the following staff for September 2001: A part-time teacher of primary English The post involves teaching the English curriculum to pupils who are within the French educational system: Classes take place on Tuesday afternoons at the Lycée, Team spirit necessary as teachers work as a team, Induction & training are offered. A part time teacher of senior secondary history-geography in English A part time teacher of secondary mathematics in English Teachers must be mother-tongue English speakers and have a relevant degree and/or teaching qualification. For the history-geography post, either history or geography degrees are acceptable. Please send your c.v. and a letter of application to Peter Woodburn, Head, English National Programme, Lycée International, 01216 Ferney-Voltaire, France. (Email: engnat@hotmail.com) Telephone 04 50 40 82 66 for further details of posts. Ple...
How to obtain the covariant form of Maxwell's equations from the continuity equation
International Nuclear Information System (INIS)
Heras, Jose A
2009-01-01
The covariant Maxwell equations are derived from the continuity equation for the electric charge. This result provides an axiomatic approach to Maxwell's equations in which charge conservation is emphasized as the fundamental axiom underlying these equations
Self-dual Maxwell-Chern-Simons theory on a cylinder
Energy Technology Data Exchange (ETDEWEB)
Han, Jongmin [Department of Mathematics, Kyung Hee University, Seoul, 130-701 (Korea, Republic of); Kim, Seongtag, E-mail: jmhan@khu.ac.kr, E-mail: stkim@inha.ac.kr [Department of Mathematics Education, Inha University, Incheon, 402-751 (Korea, Republic of)
2011-04-01
In this paper, we study the relativistic Maxwell-Chern-Simons vortices on an asymptotically flat cylinder. A topological multivortex solution is constructed by variational methods, and the Maxwell and the Chern-Simons limits are verified.
Pollution free discretization of Maxwell's equations in terms of potentials
International Nuclear Information System (INIS)
Jaun, A.; Appert, K.; Vaclavik, J.
1994-03-01
A 2D discretization of Maxwell's equations is studied in terms of the electromagnetic potentials using linear and cubic finite elements. The formulation is first analyzed with respect to the discrete dispersion properties to show that it is pollution free. It is then further applied to a simple cylindrical waveguide problem, showing good convergence to the analytical eigenfrequencies. (author) 6 figs., 13 refs
Maxwell-Vlasov equations as a continuous Hamiltonian system
International Nuclear Information System (INIS)
Morrison, P.J.
1980-09-01
The well-known Maxwell-Vlasov equations that describe a collisionless plasma are cast into Hamiltonian form. The dynamical variables are the physical although noncanonical variables E, B and f. We present a Poisson bracket which acts on these variables and the energy functional to produce the equations of motion
Maxwell-Vlasov equations as a continuous Hamiltonian system
International Nuclear Information System (INIS)
Morrison, P.J.
1980-11-01
The well-known Maxwell-Vlasov equations that describe a collisionless plasma are cast into Hamiltonian form. The dynamical variables are the physical although noncanonical variables E, B, and f. We present a Poisson bracket which acts on these variables and the energy functional to produce the equations of motion
Second order guiding-center Vlasov–Maxwell equations
DEFF Research Database (Denmark)
Madsen, Jens
2010-01-01
Second order gyrogauge invariant guiding-center coordinates with strong E×B-flow are derived using the Lie transformation method. The corresponding Poisson bracket structure and equations of motion are obtained. From a variational principle the explicit Vlasov–Maxwell equations are derived...
Internal stabilization of Maxwell's equations in heterogeneous media
Directory of Open Access Journals (Sweden)
Cristina Pignotti
2005-09-01
Full Text Available We consider the internal stabilization of Maxwell's equations with Ohm's law with space variable coefficients in a bounded region with a smooth boundary. Our result is mainly based on an observability estimate, obtained in some particular cases by the multiplier method, a duality argument and a weakening of norm argument, and arguments used in internal stabilization of scalar wave equations.
The Maxwell equations in a uniformly accelerated frame
International Nuclear Information System (INIS)
Torres del Castillo, G.F.; Perez S, C.I.
2007-01-01
The solution of the source-free Maxwell equations in a uniformly accelerated frame of reference is expressed in terms of a single complex scalar potential that obeys a second-order equation. The field of a static electric charge is obtained as an example of a stationary axisymmetric field. (Author)
Incompressible Einstein–Maxwell fluids with specified electric fields
Indian Academy of Sciences (India)
The Einstein–Maxwell equations describing static charged spheres with uniform density and variable electric field intensity are studied. The special case of constant electric field is also studied. The evolution of the model is governed by a hypergeometric differential equation which has a general solution in terms of special ...
Maxwell's Demon and the Second Law of Thermodynamics
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 6. Maxwell's Demon and the Second Law of Thermodynamics. P Radhakrishnamurty. General Article Volume 15 Issue 6 June 2010 pp 548-560. Fulltext. Click here to view fulltext PDF. Permanent link:
Maxwell's Demon and the Second Law of Thermodynamics
Indian Academy of Sciences (India)
Since its original appearance in Carnot's memoir, the principle was always formulated as a completely general statement, as free of exceptions as Newton's laws of ..... GENERAL ARTICLE operating in a thermodynamically reversible fashion. The real reason Maxwell's demon could not violate the second law dawned.
Ito terms and the Maxwell field on the lattice
International Nuclear Information System (INIS)
D'Olivo, J.C.; Socolovsky, M.
1988-01-01
If lattice renormalization effects are ignored and the number of space-time dimensions is less than four, it is explicitly shown that the effective continuum action for the Maxwell field does not contain the so-called Ito terms. As is known, the qualitative reason for this result is the flat character of the integration measure
Maxwell's Demon and the Second Law of Thermodynamics
Indian Academy of Sciences (India)
A century and a half ago, Maxwell introduced a thought experiment to illustrate the difficulties which arise in trying to apply the second law of thermodynamics at the level of molecules. He imagined an entity (since personified as. 'Mawell's demon') which could sort molecules into hot and cold and thereby create differences ...
Dong, Wan-Tao; Lü, Ze-Bin; Song, Min
2014-06-01
To explore guiding role of three-column theory in manipulative reduction, small splint fixation and early rehabilitative exercises of Colles fracture. From August 2011 to February 2012,47 patients with Colles fractures were treated by manipulative reduction small splinting fixation and early rehabilitative exercises under the guidance of three-column theory, including 21 males and 26 females aged from 40 to 76 years old with an average of (65.5 +/- 2.3). According to AO fracture classification, 27 patients were type A (including 18 cases with type A2 and 9 cases with type A3) and 20 patients were type C (including 10 cases with type C1, 6 cases with type C2 and 4 cases with type C3). Pain and recovery time of swelling, postoperative complications were observed and recorded, Gartland-Werley scoring system were applied for evaluate functional recovery and biomechanical analysis of wrist joint at 12 weeks after operation. All patients were followed up for 3 to 9 months with average of 5 months. Pain relief time ranged from 5 to 15 d with average of (7.6 +/- 2.2) d,recovery time of swelling of opisthenar was for 6 to 13 d with an average of (8.9 +/- 1.9) d. Two patients occurred tension vesicle within 3 days after operation, but no other complications occurred. According to Gartland-Werley scoring system, 25 cases got excellent results, 18 cases good and 4 cases moderate at 12 weeks after operation. Under the guidance of three-column theory, treating Colles fracture by manipulative reduction, small splinting fixation and early rehabilitative exercises can reduce pain and swelling time, promote union of fracture, effectively rehabilitate wrist function, improve clinical efficacy, and fit for concept of biomechanics.
Valoración del efecto de la calcitonina en la consolidación de la fractura de Colles
Paz Jiménez, José; López-Fanjul Menéndez, J. C.; Riera Gonzalez, Luis; Menéndez Rodríguez, A.J.; Suárez Vázquez, A.
1990-01-01
Se estudian cuarenta pacientes en que se ha producido una Fractura de Epífisis Distal de Radio (Fractura de POUTEAU-COLLES) en pacientes mayores de cincuenta años, con signos de osteoroporosis. Se han hecho dos grupos aleatorios de veinte pacientes. El grupo A se ha tratado con un programa de calcitonina y calcio que cubre los tres primeros meses. El grupo B es tratado exclusivamente con calcio, por igual período. En ambos la reducción e inmovilización sigue los mismos cr...
2012-10-26
... Inventory Completion: Maxwell Museum of Anthropology, University of New Mexico, Albuquerque, NM; Correction... affiliated with the human remains may contact the Maxwell Museum of Anthropology. Repatriation of the human..., Maxwell Museum of Anthropology, MSC01 1050, University of New Mexico, Albuquerque, NM 87131-0001...
2011-09-13
...: Maxwell Museum of Anthropology, University of New Mexico, Albuquerque, NM AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Maxwell Museum of Anthropology, University of New Mexico has... contact the Maxwell Museum of Anthropology, University of New Mexico. Repatriation of the human remains to...
2012-08-02
... Inventory Completion: Maxwell Museum of Anthropology, University of New Mexico, Albuquerque, NM AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Maxwell Museum of Anthropology has completed... has a cultural affiliation with the human remains should contact the Maxwell Museum of Anthropology at...
2012-10-26
... Inventory Completion: Maxwell Museum of Anthropology, University of New Mexico, Albuquerque, NM AGENCY... affiliated with the human remains may contact the Maxwell Museum of Anthropology. Repatriation of the human..., Maxwell Museum of Anthropology, MSC01 1050, University of New Mexico, Albuquerque, NM 87131-0001...
Representing the Electromagnetic Field: How Maxwell's Mathematics Empowered Faraday's Field Theory
Tweney, Ryan D.
2011-01-01
James Clerk Maxwell "translated" Michael Faraday's experimentally-based field theory into the mathematical representation now known as "Maxwell's Equations." Working with a variety of mathematical representations and physical models Maxwell extended the reach of Faraday's theory and brought it into consistency with other…
Knotted optical vortices in exact solutions to Maxwell's equations
de Klerk, Albertus J. J. M.; van der Veen, Roland I.; Dalhuisen, Jan Willem; Bouwmeester, Dirk
2017-05-01
We construct a family of exact solutions to Maxwell's equations in which the points of zero intensity form knotted lines topologically equivalent to a given but arbitrary algebraic link. These lines of zero intensity, more commonly referred to as optical vortices, and their topology are preserved as time evolves and the fields have finite energy. To derive explicit expressions for these new electromagnetic fields that satisfy the nullness property, we make use of the Bateman variables for the Hopf field as well as complex polynomials in two variables whose zero sets give rise to algebraic links. The class of algebraic links includes not only all torus knots and links thereof, but also more intricate cable knots. While the unknot has been considered before, the solutions presented here show that more general knotted structures can also arise as optical vortices in exact solutions to Maxwell's equations.
Black hole dynamics in Einstein-Maxwell-dilaton theory
Hirschmann, Eric W.; Lehner, Luis; Liebling, Steven L.; Palenzuela, Carlos
2018-03-01
We consider the properties and dynamics of black holes within a family of alternative theories of gravity, namely Einstein-Maxwell-dilaton theory. We analyze the dynamical evolution of individual black holes as well as the merger of binary black hole systems. We do this for a wide range of parameter values for the family of Einstein-Maxwell-dilaton theories, investigating, in the process, the stability of these black holes. We examine radiative degrees of freedom, explore the impact of the scalar field on the dynamics of merger, and compare with other scalar-tensor theories. We argue that the dilaton can largely be discounted in understanding merging binary systems and that the end states essentially interpolate between charged and uncharged, rotating black holes. For the relatively small charge values considered here, we conclude that these black hole systems will be difficult to distinguish from their analogs within General Relativity.
Maxwell-Like Equations for Free Dirac Electrons
Bruce, S. A.
2018-03-01
In this article, we show that the wave equation for a free Dirac electron can be represented in a form that is analogous to Maxwell's electrodynamics. The electron bispinor wavefunction is explicitly expressed in terms of its real and imaginary components. This leads us to incorporate into it appropriate scalar and pseudo-scalar fields in advance, so that a full symmetry may be accomplished. The Dirac equation then takes on a form similar to that of a set of inhomogeneous Maxwell's equations involving a particular self-source. We relate plane wave solutions of these equations to waves corresponding to free Dirac electrons, identifying the longitudinal component of the electron motion, together with the corresponding Zitterbewegung ("trembling motion").
Nonlinear gyrokinetic Maxwell-Vlasov equations using magnetic coordinates
International Nuclear Information System (INIS)
Brizard, A.
1988-09-01
A gyrokinetic formalism using magnetic coordinates is used to derive self-consistent, nonlinear Maxwell-Vlasov equations that are suitable for particle simulation studies of finite-β tokamak microturbulence and its associated anomalous transport. The use of magnetic coordinates is an important feature of this work as it introduces the toroidal geometry naturally into our gyrokinetic formalism. The gyrokinetic formalism itself is based on the use of the Action-variational Lie perturbation method of Cary and Littlejohn, and preserves the Hamiltonian structure of the original Maxwell-Vlasov system. Previous nonlinear gyrokinetic sets of equations suitable for particle simulation analysis have considered either electrostatic and shear-Alfven perturbations in slab geometry, or electrostatic perturbations in toroidal geometry. In this present work, fully electromagnetic perturbations in toroidal geometry are considered. 26 refs
Maxwell iteration for the lattice Boltzmann method with diffusive scaling
Zhao, Weifeng; Yong, Wen-An
2017-03-01
In this work, we present an alternative derivation of the Navier-Stokes equations from Bhatnagar-Gross-Krook models of the lattice Boltzmann method with diffusive scaling. This derivation is based on the Maxwell iteration and can expose certain important features of the lattice Boltzmann solutions. Moreover, it will be seen to be much more straightforward and logically clearer than the existing approaches including the Chapman-Enskog expansion.
Derivation of special relativity from Maxwell and Newton.
Dunstan, D J
2008-05-28
Special relativity derives directly from the principle of relativity and from Newton's laws of motion with a single undetermined parameter, which is found from Faraday's and Ampère's experimental work and from Maxwell's own introduction of the displacement current to be the -c(-2) term in the Lorentz transformations. The axiom of the constancy of the speed of light is quite unnecessary. The behaviour and the mechanism of the propagation of light are not at the foundations of special relativity.
Algorithm development for Maxwell's equations for computational electromagnetism
Goorjian, Peter M.
1990-01-01
A new algorithm has been developed for solving Maxwell's equations for the electromagnetic field. It solves the equations in the time domain with central, finite differences. The time advancement is performed implicitly, using an alternating direction implicit procedure. The space discretization is performed with finite volumes, using curvilinear coordinates with electromagnetic components along those directions. Sample calculations are presented of scattering from a metal pin, a square and a circle to demonstrate the capabilities of the new algorithm.
On the hidden maxwell superalgebra underlying D = 4 supergravity
Energy Technology Data Exchange (ETDEWEB)
Penafiel, D.M. [Departamento de Fisica, Universidad de Concepcion (Chile); DISAT, Politecnico di Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Torino (Italy); Ravera, L. [DISAT, Politecnico di Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Torino (Italy)
2017-09-15
In this work, we expand the hidden AdS-Lorentz superalgebra underlying D = 4 supergravity, reaching a (hidden) Maxwell superalgebra. The latter can be viewed as an extension involving cosmological constant of the superalgebra underlying D = 4 supergravity in flat spacetime. We write the Maurer-Cartan equations in this context and we find some interesting extensions of the antisymmetric 3-form A{sup (3)} appearing in the Free Differential Algebra in Minkowski space. The structure of Free Differential Algebras is obtained by considering the zero curvature equations. We write the parametrization of A{sup (3)} in terms of 1-forms and we rend the topological features of its extensions manifest. We interestingly find out that the structure of these extensions, and consequently the structure of the corresponding boundary contribution dA{sup (3)}, strongly depends on the form of the extra fermionic generator appearing in the hidden Maxwell superalgebra. The model we develop in this work is defined in an enlarged superspace with respect to the ordinary one, and the extra bosonic and fermionic 1-forms required for the closure of the hidden Maxwell superalgebra must be considered as physical fields in this enlarged superspace. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Maxwell-type behaviour from a geometrical structure
International Nuclear Information System (INIS)
Itin, Yakov
2006-01-01
We study which geometric structure can be constructed from the vierbein (frame/coframe) variables and which field models can be related to this geometry. The coframe field models, alternative to GR, are known as viable models for gravity, since they have the Schwarzschild solution. Since the local Lorentz invariance is violated, a physical interpretation of additional six degrees of freedom is required. The geometry of such models is usually given by two different connections-the Levi-Civita symmetric and metric-compatible connection and the Weitzenboeck flat connection. We construct a general family of linear connections of the same type, which includes two connections above as special limiting cases. We show that for dynamical propagation of six additional degrees of freedom it is necessary for the gauge field of infinitesimal transformations (antisymmetric tensor) to satisfy the system of two first-order differential equations. This system is similar to the vacuum Maxwell system and even coincides with it on a flat manifold. The corresponding 'Maxwell-compatible connections' are derived. Alternatively, we derive the same Maxwell-type system as a symmetry condition of the viable model Lagrangian. Consequently, we derive a nontrivial decomposition of the coframe field to the pure metric field plus a dynamical field of infinitesimal Lorentz rotations. An exact spherical-symmetric solution for our dynamical field is derived. It is bounded near the Schwarzschild radius. Further off, the solution is close to the Coulomb field
A systematic approach to numerical dispersion in Maxwell solvers
Blinne, Alexander; Schinkel, David; Kuschel, Stephan; Elkina, Nina; Rykovanov, Sergey G.; Zepf, Matt
2018-03-01
The finite-difference time-domain (FDTD) method is a well established method for solving the time evolution of Maxwell's equations. Unfortunately the scheme introduces numerical dispersion and therefore phase and group velocities which deviate from the correct values. The solution to Maxwell's equations in more than one dimension results in non-physical predictions such as numerical dispersion or numerical Cherenkov radiation emitted by a relativistic electron beam propagating in vacuum. Improved solvers, which keep the staggered Yee-type grid for electric and magnetic fields, generally modify the spatial derivative operator in the Maxwell-Faraday equation by increasing the computational stencil. These modified solvers can be characterized by different sets of coefficients, leading to different dispersion properties. In this work we introduce a norm function to rewrite the choice of coefficients into a minimization problem. We solve this problem numerically and show that the minimization procedure leads to phase and group velocities that are considerably closer to c as compared to schemes with manually set coefficients available in the literature. Depending on a specific problem at hand (e.g. electron beam propagation in plasma, high-order harmonic generation from plasma surfaces, etc.), the norm function can be chosen accordingly, for example, to minimize the numerical dispersion in a certain given propagation direction. Particle-in-cell simulations of an electron beam propagating in vacuum using our solver are provided.
Association du personnel
2006-01-01
The Staff Association will shortly be renewing the mandate of half of the Staff Council. This is an opportunity for you to become more directly involved in the Staff Association's work and help promote and defend the staff's interests and, more broadly, those of the Organization itself.
Steckelings, U. Muscha; de Mey, Jo G. R.; Pinto-Sietsma, Sara-Joan; Henrion, Daniel; Unger, Thomas
2011-01-01
The 15th Annual Meeting of the European Council of Cardiovascular Research brought together basic and clinical scientists working in the cardiovascular field in La Colle sur Loup, France. Upfront basic and clinical research addressing the mechanisms of disease, identification of biomarkers or
Directory of Open Access Journals (Sweden)
Hemsen L
2013-02-01
Full Text Available Lisa Hemsen,1 Susan L Cusack,2 Harold S Minkowitz,3 Michael E Kuss41Innocoll Technologies, Athlone, Ireland; 2Cusack Pharmaceutical Consulting, Burlington, NJ, USA; 3Memorial Hermann Memorial City Medical Center, Houston, TX, USA; 4Premier Research Group, Austin, TX, USABackground: XaraColl, a collagen-based implant that delivers bupivacaine to sites of surgical trauma, has been shown to reduce postoperative pain and use of opioid analgesia in patients undergoing open surgery. We therefore designed and conducted a preliminary feasibility study to investigate its application and ease of use for laparoscopic surgery.Methods: We implanted four XaraColl implants each containing 50 mg of bupivacaine hydrochloride (200 mg total dose in ten men undergoing laparoscopic inguinal or umbilical hernioplasty. Postoperative pain intensity and use of opioid analgesia were recorded through 72 hours for comparison with previously reported data from efficacy studies performed in men undergoing open inguinal hernioplasty. Safety was assessed for 30 days.Results: XaraColl was easily and safely implanted via a laparoscope. The summed pain intensity and total use of opioid analgesia through the first 24 hours were similar to the values observed in previously reported studies for XaraColl-treated patients after open surgery, but were lower through 48 and 72 hours.Conclusion: XaraColl is suitable for use in laparoscopic surgery and may provide postoperative analgesia in laparoscopic patients who often experience considerable postoperative pain in the first 24–48 hours following hospital discharge. Randomized controlled trials specifically to evaluate its efficacy in this application are warranted.Keywords: laparoscopic, hernioplasty, hernia repair
Generating solutions to the Einstein-Maxwell equations
Contopoulos, I. G.; Esposito, F. P.; Kleidis, K.; Papadopoulos, D. B.; Witten, L.
2015-09-01
The Einstein-Maxwell (E-M) equations in a curved spacetime that admits at least one Killing vector are derived, from a Lagrangian density adapted to symmetries. In this context, an auxiliary space of potentials is introduced, in which, the set of potentials associated to an original (seed) solution of the E-M equations are transformed to a new set, either by continuous transformations or by discrete transformations. In this paper, continuous transformations are considered. Accordingly, originating from the so-called γA-metric, other exact solutions to the E-M equations are recovered and discussed.
Nonlocal symmetries and nonlocal conservation laws of Maxwell's equations
International Nuclear Information System (INIS)
Anco, S.C.; Bluman, G.
1997-01-01
Nonlocal symmetries are obtained for Maxwell's equations in three space-time dimensions through the use of two potential systems involving scalar and vector potentials for the electromagnetic field. Corresponding nonlocal conservation laws are derived from these symmetries. The conservation laws yield nine functionally independent constants of motion which cannot be expressed in terms of the constants of motion arising from local conservation laws for space-time symmetries. These nine constants of motion represent additional conserved quantities for the electromagnetic field in three space endash time dimensions. copyright 1997 American Institute of Physics
Traffic restrictions on Routes Bloch, Maxwell and Bohr
IT Department
2008-01-01
Excavation and pipework is being carried out in the framework of the transfer of the waste water treatment plant for the effluents from the surface treatment workshops from Building 254 to Building 676, currently under construction. This work may encroach onto Routes Bloch, Maxwell and Bohr and disrupt the flow of traffic. Users are requested to comply with the road signs that will be erected. The work is expected to last until the beginning of December 2008. Thank you for your understanding. TS/CE and TS/FM Groups Tel.7 4188 or 16 4314
Wormhole Solutions in the Presence of Nonlinear Maxwell Field
Directory of Open Access Journals (Sweden)
S. H. Hendi
2014-01-01
Full Text Available In generalizing the Maxwell field to nonlinear electrodynamics, we look for the magnetic solutions. We consider a suitable real metric with a lower bound on the radial coordinate and investigate the properties of the solutions. We find that in order to have a finite electromagnetic field near the lower bound, we should replace the Born-Infeld theory with another nonlinear electrodynamics theory. Also, we use the cut-and-paste method to construct wormhole structure. We generalize the static solutions to rotating spacetime and obtain conserved quantities.
Conformastatic disk-haloes in Einstein-Maxwell gravity
Gutiérrez-Piñeres, Antonio C.; González, Guillermo A.; Quevedo, Hernando
2013-02-01
We present a relativistic model describing a thin disk surrounded by a halo in the presence of an electromagnetic field. The model is obtained by solving the Einstein-Maxwell equations on a particular conformastatic spacetime background and by using the distributional approach for the energy-momentum tensor. A class of solutions is obtained in which the gravitational and electromagnetic potentials are completely determined by a harmonic function only. A particular solution is given that is asymptotically flat and singularity free, and satisfies all the energy conditions.
Operational derivation of Boltzmann distribution with Maxwell's demon model.
Hosoya, Akio; Maruyama, Koji; Shikano, Yutaka
2015-11-24
The resolution of the Maxwell's demon paradox linked thermodynamics with information theory through information erasure principle. By considering a demon endowed with a Turing-machine consisting of a memory tape and a processor, we attempt to explore the link towards the foundations of statistical mechanics and to derive results therein in an operational manner. Here, we present a derivation of the Boltzmann distribution in equilibrium as an example, without hypothesizing the principle of maximum entropy. Further, since the model can be applied to non-equilibrium processes, in principle, we demonstrate the dissipation-fluctuation relation to show the possibility in this direction.
The free energy of Maxwell-Vlasov equilibria
International Nuclear Information System (INIS)
Morrison, P.J.; Pfirsch, D.
1989-10-01
A previously derived expression for the energy of arbitrary perturbations about arbitrary Vlasov-Maxwell equilibria is transformed into a very compact form. The new form is also obtained by a canonical transformation method for solving Vlasov's equation, which is based on Lie group theory. This method is simpler than the one used before and provides better physical insight. Finally a procedure is presented for determining the existence of negative-energy modes. In this context the question of why there is an accessibility constraint for the particles, but not for the fields, is discussed. 16 refs
US Agency for International Development — E3 Staff database is maintained by E3 PDMS (Professional Development & Management Services) office. The database is Mysql. It is manually updated by E3 staff as...
Decentralized Ground Staff Scheduling
DEFF Research Database (Denmark)
Sørensen, M. D.; Clausen, Jens
2002-01-01
Typically, ground staff scheduling is centrally planned for each terminal in an airport. The advantage of this is that the staff is efficiently utilized, but a disadvantage is that staff spends considerable time walking between stands. In this paper a decentralized approach for ground staff...... scheduling is investigated. The airport terminal is divided into zones, where each zone consists of a set of stands geographically next to each other. Staff is assigned to work in only one zone and the staff scheduling is planned decentralized for each zone. The advantage of this approach is that the staff...... work in a smaller area of the terminal and thus spends less time walking between stands. When planning decentralized the allocation of stands to flights influences the staff scheduling since the workload in a zone depends on which flights are allocated to stands in the zone. Hence solving the problem...
African Journals Online (AJOL)
Internal Audit, Military. Museums, Documentation. Service, Language. Service, Financial Co-ordination, Chief Pay Mas- ter, Programming and Budget, Electronic Data. Processing and Expenditure Control. Chief of Staff Finance. With effect from 13 February 1978 Chief of Staff. Management Services became Chief of Staff.
Association du personnel
2007-01-01
The Staff Association will shortly be renewing the mandate of half of the Staff Council. This is an opportunity for you to become more directly involved in the Staff Association’s work and help promote and defend the staff’s interests and, more broadly, those of the Organization itself.
Maxwell's equations, quantum physics and the quantum graviton
International Nuclear Information System (INIS)
Gersten, Alexander; Moalem, Amnon
2011-01-01
Quantum wave equations for massless particles and arbitrary spin are derived by factorizing the d'Alembertian operator. The procedure is extensively applied to the spin one photon equation which is related to Maxwell's equations via the proportionality of the photon wavefunction Ψ to the sum E + iB of the electric and magnetic fields. Thus Maxwell's equations can be considered as the first quantized one-photon equation. The photon wave equation is written in two forms, one with additional explicit subsidiary conditions and second with the subsidiary conditions implicitly included in the main equation. The second equation was obtained by factorizing the d'Alembertian with 4×4 matrix representation of 'relativistic quaternions'. Furthermore, scalar Lagrangian formalism, consistent with quantization requirements is developed using derived conserved current of probability and normalization condition for the wavefunction. Lessons learned from the derivation of the photon equation are used in the derivation of the spin two quantum equation, which we call the quantum graviton. Quantum wave equation with implicit subsidiary conditions, which factorizes the d'Alembertian with 8×8 matrix representation of relativistic quaternions, is derived. Scalar Lagrangian is formulated and conserved probability current and wavefunction normalization are found, both consistent with the definitions of quantum operators and their expectation values. We are showing that the derived equations are the first quantized equations of the photon and the graviton.
Saff Association
2013-01-01
2013 Elections to Staff Council Vote! Make your voice heard and be many to elect the new Staff Council. More details on the elections can be found on the Staff Association web site (https://ap-vote.web.cern.ch/elections-2013). Timetable elections Monday 28 October to Monday 11 November, 12:00 am voting Monday 18 and Monday 25 November, publication of the results in Echo Tuesday 19 November, Staff Association Assizes Tuesday 3 December, first meeting of the new Staff Council and election of the new Executive Committee The voting procedure is monitored by the Election Committee.
Primera cita de Culicoides paradoxalis Ramilo & Delécolle, 2013 (Diptera, Ceratopogonidae en España
Directory of Open Access Journals (Sweden)
Sánchez Murillo, J. M.
2015-12-01
Full Text Available The ceratopogonid Culicoides paradoxalis Ramilo & Delécolle, 2013 is recorded for the first time in Spain based on reliable morphological evidence according to the previous descriptions of other authors. A total of 438 females (349 nulliparous and 89 parous and a single male were collected with CDC miniature light traps at three different livestock-associated locations in Extremadura Autonomous Community (Spain in 2014. Most specimens were captured between June and August, suggesting a univoltine pattern for this species extended over summer and early autumn. Although the number of collections of C. paradoxalis is low in comparison with the dominant species, the occurrence of this species in monitoring surveillance programs should deserve specific attention in order to estimate the accurate ratio of potential vectors unmistakably. Interesting information about the period of flight and illustrated morphological features are presented for C. paradoxalis in the current paper.Se cita por primera vez en España el ceratopogónido Culicoides paradoxalis Ramilo & Delécolle, 2013, basándose en evidencias morfológicas de acuerdo a las descripciones previas de otros autores. Un total de 438 hembras (349 nulíparas y 89 paras y un macho se recolectaron con minitrampas de luz CDC en tres localidades ganaderas en la Comunidad Autónoma de Extremadura (España en 2014. La mayor parte de los especímenes fueron capturados entre junio y agosto, mostrando un único período de vuelo que se extendió durante todo el verano y principios del otoño. Aunque el número de capturas de C. paradoxalis es reducido en comparación con los Culicoides dominantes, la aparición de esta nueva especie merece especial atención en los programas de vigilancia entomológica con el fin de estimar inequívocamente la proporción exacta de vectores potenciales. Se presenta en este artículo información de interés sobre el período de vuelo así como fotografías de las
Comments on Dirac-like monopole, Maxwell and Maxwell-Chern-Simons electrodynamics in D=(2+1)
International Nuclear Information System (INIS)
Moura-Melo, Winder A.; Helayel Neto, J.A.
2000-05-01
Classical Maxwell and Maxwell-Chern-Simons Electrodynamics in (2+1) D are studied in some details. General expressions for the potential and fields are obtained for both models, and some particular cases are explicitly solved. Conceptual and technical difficulties arise, however, for accelerated charges. The propagation of electromagnetic signals is also studied and their reverberation is worked out and discussed. Furthermore, we show that a Dirac-like monopole yields a (static) tangential electric field. We also discuss some classical and quantum consequences of the field created by such a monopole when acting upon an usual electric charge. In particular, we show that at large distances, the dynamics of one single charged particle under the action of such a potential and a constant (external) magnetic field as well, reduces to that of one central harmonic oscillator, presenting, however, an interesting angular sector which admits energy-eigenvalues. For example, the quantisation of these eigenvalues yields a Dirac-like condition on the product of the charges. Moreover, such eigenvalues are shown to feel (and respond) to discrete shift of the angle variable. We also raise the question on the possibility of the formation pf bound states in this system. (author)
On the Physical Origin of the Oppenheimer-Ahluwalia Zero-Energy Solutions of Maxwell Equations
Chubykalo, Andrew E.
By virtue of the Chubykalo-Smirnov-Rueda generalized form of the Maxwell-Lorentz equation, a new form of the energy density of the electromagnetic field is obtained. This result allows us to explain a physical origin of the Oppenheimer-Ahluwalia zero-energy solutions of the Maxwell equations.
On Bianchi-I cosmic strings coupled with Maxwell fields in bimetric ...
Indian Academy of Sciences (India)
with electromagnetic field in Rosen's bimetric theory of relativity and observed that there is no contribution from cosmic strings and Maxwell fields in this theory. Keywords. Bianchi-I; cosmic strings; Maxwell fields; bimetric relativity; axially symmetric; singu- larity; vacuum model. PACS Nos 04.20.-q; 03.50.De; 11.27.+d; 41.20.
Array-structure theory of Maxwell wavefields in affine (3 + 1)-spacetime : An overview
De Hoop, A.T.
2013-01-01
An array-structure theory of Maxwell wavefields in affine (3 + 1)-spacetime is presented. The structure is designed to supersede the conventional Gibbs vector calculus and Heaviside vectorial Maxwell equations formulations, deviates from the Einstein view on spacetime as having a metrical structure
Daura, J.; Sanz, M.; Allué, E.; Vaquero, M.; López-García, J. M.; Sánchez-Marco, A.; Domènech, R.; Martinell, J.; Carrión, J. S.; Ortiz, J. E.; Torres, T.; Arnold, L. J.; Benson, A.; Hoffmann, D. L.; Skinner, A. R.; Julià, R.
2017-12-01
Marine isotope stage 3 (MIS 3) was characterised by marked oscillations of extreme cold episodes with very short warm events during the stadial, and several regional differences have been recorded in the ice cores and marine deposits. The aim of this study is to reconstruct this period by evaluating both terrestrial and regional responses. Cova del Coll Verdaguer, a site located on the Iberian Peninsula, preserves a sedimentary deposit dated to between 34 and 56 ka BP and provides an opportunity for evaluating the impact of climate changes on the regional landmass during a period that coincided with the last Neanderthal population on the Iberian Peninsula. Several dating methods, including U-series, electron spin resonance, amino acid racemization and radiocarbon (14C), were applied to the site and the ages obtained show good agreement. The biotic evidence obtained is substantial, comprising floristic data from palynology and charcoal analysis, and faunal data from large and small mammals, birds and gastropods. Environmental reconstruction points to an initially open meadow landscape at the base of the sequence (∼56 ka) that progressively changes to a woodland environment dominated by conifers (∼34 ka). The presence of few thermophilous taxa, in contrast with lower latitudes of the Iberian Peninsula, is also detected. The environmental conditions of mid-altitude, Mediterranean, limestone mountains for the last Neanderthal populations appear to have been dominated by a forested landscape comprising boreal or mixed coniferous forest, characterised by a low usable biomass with poor comestible plant resources and dispersed herbivore populations.
Faut-il supprimer la géographie au collège et au lycée ?
Directory of Open Access Journals (Sweden)
Anne Le Roux
1999-05-01
Full Text Available Faut-il supprimer la géographie… au collège et au lycée ? Oui, tant que les géographes (de plus en plus nombreux continueront à se désintéresser de la formation initiale (Deug, Licence, Concours d´enseignement et continue des professeurs de géographie, qui sont historiens à presque 90% du total des " professeurs d´histoire-géographie " du second degré. Après tout, si la géographie à enseigner au Collège et au Lycée arrive à un tel écart avec la géographie de la recherche ou la géographie di...
Limited-diffraction solutions to Maxwell and Schroedinger equations
International Nuclear Information System (INIS)
Lu, Jian-yu; Greenleaf, J.F.
1996-10-01
The authors have developed a new family of limited diffraction electromagnetic X-shaped waves based on the scalar X-shaped waves discovered previously. These waves are diffraction-free in theory and particle-like (wave packets), in that they maintain their shape as they propagate to an infinite distance. The 'X waves' possess (theoretically) infinitely extended 'arms' and - at least, the ones studied in this paper - have an infinite total energy: therefore, they are not physically realizable. However, they can be truncated in both space and time and 'approximated' by means of a finite aperture radiator so to get a large enough depth of interest (depth of field). In addition to the Maxwell equations, X wave solutions to the free Schroedinger equation are also obtained. Possible applications of these new waves are discussed. Finally, the authors discuss the appearance of the X-shaped solutions from the purely geometric point of view of the special relativity theory
H-theorem and Maxwell demon in quantum physics
Kirsanov, N. S.; Lebedev, A. V.; Sadovskyy, I. A.; Suslov, M. V.; Vinokur, V. M.; Blatter, G.; Lesovik, G. B.
2018-02-01
The Second Law of Thermodynamics states that temporal evolution of an isolated system occurs with non-diminishing entropy. In quantum realm, this holds for energy-isolated systems the evolution of which is described by the so-called unital quantum channel. The entropy of a system evolving in a non-unital quantum channel can, in principle, decrease. We formulate a general criterion of unitality for the evolution of a quantum system, enabling a simple and rigorous approach for finding and identifying the processes accompanied by decreasing entropy in energy-isolated systems. We discuss two examples illustrating our findings, the quantum Maxwell demon and heating-cooling process within a two-qubit system.
Quantum entanglement of locally excited states in Maxwell theory
International Nuclear Information System (INIS)
Nozaki, Masahiro; Watamura, Naoki
2016-01-01
In 4 dimensional Maxwell gauge theory, we study the changes of (Rényi) entanglement entropy which are defined by subtracting the entropy for the ground state from the one for the locally excited states, generated by acting with gauge invariant local operators on the state. The changes for the operators which we consider in this paper reflect the electric-magnetic duality. The late-time value of changes can be interpreted in terms of electromagnetic quasi-particles. When the operator constructed of both electric and magnetic fields acts on the ground state, it shows that the operator acts on the late-time structure of quantum entanglement differently from free scalar fields.
Conformally invariant thermodynamics of a Maxwell-Dilaton black hole
Lopez-Monsalvo, C. S.; Nettel, F.; Quevedo, H.
2013-12-01
The thermodynamics of Maxwell-Dilaton black holes has been extensively studied. It has served as a fertile ground to test ideas about temperature through various definitions of surface gravity. In this paper, we make an independent analysis of this black hole solution in both, Einstein and Jordan, frames. We explore a set of definitions for the surface gravity and observe the different predictions they make for the near extremal configuration of this black hole. Finally, motivated by the singularity structure in the interior of the event horizon, we use a holographic argument to remove the micro-states from the disconnected region of this solution. In this manner, we construct a frame independent entropy from which we obtain a temperature which agrees with the standard results in the non-extremal regime, and has a desirable behaviour around the extremal configurations according to the third law of black hole mechanics.
On some orthogonality properties of Maxwell's multipole vectors
International Nuclear Information System (INIS)
Gramada, Apostol
2007-01-01
We determine the location of the expansion points with respect to which the two Maxwell's multipole vectors of the quadrupole moment and the dipole vector of a distribution of charge form an orthogonal trihedron. We find that with respect to these 'orthogonality centres' both the dipole and the quadrupole moments are each characterized by a single real parameter. We further show that the orthogonality centres coincide with the stationary points of the magnitude of the quadrupole moment and, therefore, they can be seen as an extension of the concept of centre of the dipole moment of a neutral system introduced previously in the literature. The nature of the stationary points then provides the means for the classification of a distribution of charge in two different categories
Maxwell's enduring legacy a scientific history of the Cavendish laboratory
Longair, Malcolm
2016-01-01
The Cavendish Laboratory is arguably the most famous physics laboratory in the world. Founded in 1874, it rapidly gained a leading international reputation through the researches of the Cavendish professors beginning with Maxwell, Rayleigh, J. J. Thomson, Rutherford and Bragg. Its name will always be associated with the discoveries of the electron, the neutron, the structure of the DNA molecule and pulsars, but these are simply the tip of the iceberg of outstanding science. The physics carried out in the laboratory is the central theme of the book and this is explained in reasonably non-technical terms. The research activities are set in their international context. Generously illustrated, with many pictures of the apparatus used and diagrams from the original papers, the story is brought right up to date with descriptions of the science carried out under the leadership of the very different personalities of Mott, Pippard and Edwards.
Fourier analysis of numerical algorithms for the Maxwell equations
Liu, Yen
1993-01-01
The Fourier method is used to analyze the dispersive, dissipative, and isotropy errors of various spatial and time discretizations applied to the Maxwell equations on multi-dimensional grids. Both Cartesian grids and non-Cartesian grids based on hexagons and tetradecahedra are studied and compared. The numerical errors are quantitatively determined in terms of phase speed, wave number, propagation direction, gridspacings, and CFL number. The study shows that centered schemes are more efficient than upwind schemes. The non-Cartesian grids yield superior isotropy and higher accuracy than the Cartesian ones. For the centered schemes, the staggered grids produce less errors than the unstaggered ones. A new unstaggered scheme which has all the best properties is introduced. The study also demonstrates that a proper choice of time discretization can reduce the overall numerical errors due to the spatial discretization.
The road to Maxwell's demon conceptual foundations of statistical mechanics
Hemmo, Meir
2012-01-01
Time asymmetric phenomena are successfully predicted by statistical mechanics. Yet the foundations of this theory are surprisingly shaky. Its explanation for the ease of mixing milk with coffee is incomplete, and even implies that un-mixing them should be just as easy. In this book the authors develop a new conceptual foundation for statistical mechanics that addresses this difficulty. Explaining the notions of macrostates, probability, measurement, memory, and the arrow of time in statistical mechanics, they reach the startling conclusion that Maxwell's Demon, the famous perpetuum mobile, is consistent with the fundamental physical laws. Mathematical treatments are avoided where possible, and instead the authors use novel diagrams to illustrate the text. This is a fascinating book for graduate students and researchers interested in the foundations and philosophy of physics.
Numerical analysis of Sakiadis flow problem considering Maxwell nanofluid
Directory of Open Access Journals (Sweden)
Mustafa Meraj
2017-01-01
Full Text Available This article investigates the flow of Maxwell nanofluid over a moving plate in a calm fluid. Novel aspects of Brownian motion and thermophoresis are taken into consideration. Revised model for passive control of nanoparticle volume fraction at the plate is used in this study. The formulated differential system is solved numerically by employing shooting approach together with fourth-fifth-order-Runge-Kutta integration procedure and Newton’s method. The solutions are greatly influenced with the variation of embedded parameters which include the local Deborah number, the Brownian motion parameter, the thermophoresis parameter, the Prandtl number, and the Schmidt number. We found that the variation in velocity distribution with an increase in local Deborah number is non-monotonic. Moreover, the reduced Nusselt number has a linear and direct relationship with the local Deborah number.
Chaotic Dynamics of Falling Disks: from Maxwell to Bar Tricks.
Field, Stuart
1998-03-01
Understanding the motion of flat objects falling in a viscous medium dates back to at least Newton and Maxwell, and is relevant to problems in meteorology, sedimentology, aerospace and chemical engineering, and nori/disks/pub.html>bar wagering strategies. Recent theoretical studies have emphasized the role played by deterministic chaos. Here we nori/falling.html>report(S. B. Field, M. Klaus, M. G. Moore, and F. Nori, Nature 388), 252 (1997) experimental observations and theoretical analysis of the dynamics of disks falling in water/glycerol mixtures. We find four distinct types of motion, and map out a ``phase diagram'' in the appropriate variables. The apparently complex behavior of the disks can be reduced to a series of one-dimensional maps which display a discontinuity at the crossover from periodic and chaotic motion. This discontinuity leads to an unusual intermittency transition between the two behaviors, which has not previously been observed experimentally in any system.
Cubic interactions of Maxwell-like higher spins
Energy Technology Data Exchange (ETDEWEB)
Francia, Dario [Scuola Normale Superiore and INFN,Piazza dei Cavalieri, 7 I-56126 Pisa (Italy); Monaco, Gabriele Lo [Dipartimento di Fisica, Università di Pisa,Piazza Fibonacci, 3, I-56126, Pisa (Italy); Dipartimento di Fisica, Università di Milano-Bicocca,Piazza della Scienza 3, I-20126 Milano (Italy); Mkrtchyan, Karapet [Max Planck Institut für Gravitationsphysik,Am Mühlenberg 1, Potsdam 14476 (Germany)
2017-04-12
We study the cubic vertices for Maxwell-like higher-spins in flat and (A)dS background spaces of any dimension. Reducibility of their free spectra implies that a single cubic vertex involving any three fields subsumes a number of couplings among different particles of various spins. The resulting vertices do not involve traces of the fields and in this sense are simpler than their Fronsdal counterparts. We propose an extension of both the free theory and of its cubic deformation to a more general class of partially reducible systems, that one can obtain from the original theory upon imposing trace constraints of various orders. The key to our results is a version of the Noether procedure allowing to systematically account for the deformations of the transversality conditions to be imposed on the gauge parameters at the free level.
Holographic Fermions in Anisotropic Einstein-Maxwell-Dilaton-Axion Theory
Directory of Open Access Journals (Sweden)
Li-Qing Fang
2015-01-01
Full Text Available We investigate the properties of the holographic Fermionic system dual to an anisotropic charged black brane bulk in Einstein-Maxwell-Dilaton-Axion gravity theory. We consider the minimal coupling between the Dirac field and the gauge field in the bulk gravity theory and mainly explore the dispersion relation exponents of the Green functions of the dual Fermionic operators in the dual field theory. We find that along both the anisotropic and the isotropic directions the Fermi momentum will be effected by the anisotropy of the bulk theory. However, the anisotropy has influence on the dispersion relation which is almost linear for massless Fermions with charge q=2. The universal properties that the mass and the charge of the Fermi possibly correspond to nonlinear dispersion relation are also investigated.
Maxwell's Demons Everywhere: Evolving Design as the Arrow of Time
Bejan, Adrian
2014-02-01
Science holds that the arrow of time in nature is imprinted on one-way (irreversible) phenomena, and is accounted for by the second law of thermodynamics. Here I show that the arrow of time is painted much more visibly on another self-standing phenomenon: the occurrence and change (evolution in time) of flow organization throughout nature, animate and inanimate. This other time arrow has been present in science but not recognized as such since the birth of thermodynamics. It is Maxwell's demon. Translated in macroscopic terms, this is the physics of the phenomenon of design, which is the universal natural tendency of flow systems to evolve into configurations that provide progressively greater access over time, and is summarized as the constructal law of design and evolution in nature. Knowledge is the ability to effect design changes that facilitate human flows on the landscape. Knowledge too flows.
A Generalization of the Einstein-Maxwell Equations
Cotton, Fredrick
2016-03-01
The proposed modifications of the Einstein-Maxwell equations include: (1) the addition of a scalar term to the electromagnetic side of the equation rather than to the gravitational side, (2) the introduction of a 4-dimensional, nonlinear electromagnetic constitutive tensor and (3) the addition of curvature terms arising from the non-metric components of a general symmetric connection. The scalar term is defined by the condition that a spherically symmetric particle be force-free and mathematically well-behaved everywhere. The constitutive tensor introduces two auxiliary fields which describe the particle structure. The additional curvature terms couple both to particle solutions and to electromagnetic and gravitational wave solutions. http://sites.google.com/site/fwcotton/em-30.pdf
Directory of Open Access Journals (Sweden)
Garg Rajesh
2010-12-01
Full Text Available We assess the finger joint stiffness by measuring the active range of motion of all metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints of the involved hand with a hand goniometer. It is then compared with the normal hand for the effective range of total motion and thereby using it as a quantitative, qualitative, and reproducible method for early diagnosis of reflex sympathetic dystrophy after Colles' fracture. It is sensitive and specific.
CSR Fields: Direct Numerical Solution of the Maxwell's Equation
International Nuclear Information System (INIS)
Novokhatski, Alexander
2011-01-01
We discuss the properties of the coherent electromagnetic fields of a very short, ultra-relativistic bunch in a rectangular vacuum chamber inside a bending magnet. The analysis is based on the results of a direct numerical solution of Maxwell's equations together with Newton's equations. We use a new dispersion-free time-domain algorithm which employs a more efficient use of finite element mesh techniques and hence produces self-consistent and stable solutions for very short bunches. We investigate the fine structure of the CSR fields including coherent edge radiation. This approach should be useful in the study of existing and future concepts of particle accelerators and ultrafast coherent light sources. The coherent synchrotron radiation (CSR) fields have a strong action on the beam dynamics of very short bunches, which are moving in the bends of all kinds of magnetic elements. They are responsible for additional energy loss and energy spread; micro bunching and beam emittance growth. These fields may bound the efficiency of damping rings, electron-positron colliders and ultrafast coherent light sources, where high peak currents and very short bunches are envisioned. This is relevant to most high-brightness beam applications. On the other hand these fields together with transition radiation fields can be used for beam diagnostics or even as a powerful resource of THz radiation. A history of the study of CSR and a good collection of references can be found in (1). Electromagnetic theory suggests several methods on how to calculate CSR fields. The most popular method is to use Lienard-Wiechert potentials. Other approach is to solve numerically the approximate equations, which are a Schrodinger type equation. These numerical methods are described in (2). We suggest that a direct solution of Maxwell's equations together with Newton's equations can describe the detailed structure of the CSR fields (3).
Maxwell's demon. (II) A quantum-theoretic exorcism
Gyftopoulos, Elias P.
2002-05-01
In Part II of this two-part paper we prove that Maxwell's demon is unable to accomplish his task of sorting air molecules into swift and slow because in air in a thermodynamic equilibrium state there are no such molecules. The proof is based on the principles of a unified quantum theory of mechanics and thermodynamics. The key idea of the unified theory is that von Neumann's concept of a homogeneous ensemble of identical systems, identically prepared, is valid not only for a density operator ρ equal to a projector (every member of the ensemble is assigned the same projector, ρi=| ψi> ρ 2, as any other member). So, the latter ensemble is not a statistical mixture of projectors. The broadening of the validity of the homogeneous ensemble is consistent with the quantum-theoretic postulates about observables, measurement results, and value of any observable. In the context of the unified theory, among the many novel results is the theorem that each molecule of a system in a thermodynamic equilibrium state has zero value of momentum, that is, each molecule is at a standstill and, therefore, there are no molecules to be sorted as swift and slow. Said differently, if Maxwell were cognizant of quantum theory, he would not have conceived of the idea of the demon. It is noteworthy that the zero value of momentum is not the result of averaging over different momenta of many molecules. Under the specified conditions, it is the quantum-theoretic value of the momentum of any one molecule, and the same result is valid even if the system consists of only one molecule.
2012-04-02
... Cultural Items: Maxwell Museum of Anthropology, University of New Mexico, Albuquerque, NM AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: The Maxwell Museum of Anthropology, in consultation... with the cultural items may contact the Maxwell Museum of Anthropology. DATES: Representatives of any...
Directory of Open Access Journals (Sweden)
Cusack SL
2013-03-01
Full Text Available Susan L Cusack,1 Philip Reginald,2 Lisa Hemsen,3 Emmanuel Umerah21Cusack Pharmaceutical Consulting, Burlington, NJ, USA; 2Departments of Gynaecology and Anaesthetics, Wexham Park Hospital, Slough, SL2 4HL, UK; 3Innocoll Technologies, Athlone, IrelandBackground: XaraColl®, a collagen-based intraoperative implant that delivers bupivacaine to the site of surgical trauma, is under development for postoperative analgesia. We examined the pharmacokinetics, safety and efficacy of XaraColl following implantation in women undergoing total abdominal hysterectomy.Methods: Three XaraColl implants, each containing 50 mg bupivacaine hydrochloride, were implanted in 12 women undergoing total abdominal hysterectomy for a benign condition. Serum samples were obtained through 96 hours for pharmacokinetic analysis. Patients received acetaminophen 1000 mg every 6 hours, diclofenac 50 mg every 8 hours, and were given access to intravenous morphine for breakthrough pain via patient-controlled analgesia during the first 24 hours. Pain intensity was assessed at regular intervals using a 100 mm visual analog scale. Safety was assessed through 30 days.Results: The pharmacokinetic profile displayed a double peak in bupivacaine concentration with the second peak occurring up to 24 hours after the first and at a generally higher concentration. The time to maximum concentration (tmax varied from 0.5 to 24 hours (median 12 hours according to which peak predominated. The mean maximum concentration (Cmax was 0.22 µg/mL and the maximum individual Cmax was 0.44 µg/mL, which are well below the established systemic toxicity threshold. Morphine use was generally low (mean 16.8 mg; median 6.5 mg and compared favorably with institutional experience. At 6 hours post-surgery, 11 patients recorded pain scores ≤ 20 mm, 6 recorded ≤ 10 mm, and 2 reported no pain. Scores continued to decline throughout the study. The product was considered safe and well tolerated.Conclusion: XaraColl
Staff Association
2011-01-01
Elections to fill all seats in the Staff Council are being organized this month. The voting takes place from the 31st of October to the 14th of November, at noon. As you may have noted when reading Echo, many issues concerning our employment conditions are on the agenda of the coming months and will keep the next Staff Council very busy. So, make your voice heard and take part in the elections for a new Staff Council. By doing so, you will be encouraging the men and women who will be representing you over the next two years and they will doubtless appreciate your gratitude. Every member of the Staff Association will have received an email containing a link to the webpage which will allow voting. If you are a member of the Staff Association and you did not receive such an email, please contact the Staff Association secretariat (staff.association@cern.ch). Do not forget to vote * * * * * * * Vote Make your voice heard and be many to elect the new Staff Council. More details on the election...
Directory of Open Access Journals (Sweden)
CRISTINA EMANUELA CASELLATO
2015-11-01
Full Text Available We present calcareous nannofossil biostratigraphy and abundances for the Upper Pliensbachian-Lower Toarcian interval, including the Toarcian Oceanic Anoxic Event (T-OAE, represented by the Fish Level at Colle di Sogno (N Italy. In addition to biohorizons identifying NJT 5 and NJT 6 nannofossil zones, the first occurrences of C. superbus and D. striatus constrain the onset and the end of the T-OAE, respectively. We propose the last occurrence of M. jansae as additional event to approximate the end of the T-OAE at lower latitudes. Quantitative data highlight the “Schizosphaerella decline” marking the Pliensbachian/Toarcian boundary and the “Schizosphaerella crisis” at the onset of the T-OAE as supplementary biohorizons. S. punctulata and M. jansae constitute most of the micrite in the interval below the Fish Level, which is marked by an increase in abundance of small coccoliths remaining abundant in the overlying interval, with limited contributions of S. punctulata, while M. jansae disappears. Principal Component Analysis implemented nannofossil paleoecological and paleoenvironmental reconstructions. The latest Pliensbachian was characterized by stable oligotrophic conditions favourable to calcification at low pCO2 levels promoting the proliferation of deep-dwelling and highly-calcified S. punctulata. During the earliest Toarcian an initial pulse of continental run-off introduced terrigenous material favouring the intermediate-dweller M. jansae and the low-salinity adapted Calyculus. Higher nutrient concentrations and ocean acidification magnified during the T-OAE, stimulatying mesotrophic low-calcified coccolith-producers and suppressing k-strategist deep- to intermediate-dwellers. After the T-OAE, partial recovery of calcareous nannoplankton indicates still perturbed conditions. Ecosystem modifications anticipated the T-OAE of ~1 million years with species origination and major changes in assemblages.
A reconstruction of Maxwell model for effective thermal conductivity of composite materials
International Nuclear Information System (INIS)
Xu, J.Z.; Gao, B.Z.; Kang, F.Y.
2016-01-01
Highlights: • Deficiencies were found in classical Maxwell model for effective thermal conductivity. • Maxwell model was reconstructed based on potential mean-field theory. • Reconstructed Maxwell model was extended with particle–particle contact resistance. • Predictions by reconstructed Maxwell model agree excellently with experimental data. - Abstract: Composite materials consisting of high thermal conductive fillers and polymer matrix are often used as thermal interface materials to dissipate heat generated from mechanical and electronic devices. The prediction of effective thermal conductivity of composites remains as a critical issue due to its dependence on considerably factors. Most models for prediction are based on the analog between electric potential and temperature that satisfy the Laplace equation under steady condition. Maxwell was the first to derive the effective electric resistivity of composites by examining the far-field spherical harmonic solution of Laplace equation perturbed by a sphere of different resistivity, and his model was considered as classical. However, a close review of Maxwell’s derivation reveals that there exist several controversial issues (deficiencies) inherent in his model. In this study, we reconstruct the Maxwell model based on a potential mean-field theory to resolve these issues. For composites made of continuum matrix and particle fillers, the contact resistance among particles was introduced in the reconstruction of Maxwell model. The newly reconstructed Maxwell model with contact resistivity as a fitting parameter is shown to fit excellently to experimental data over wide ranges of particle concentration and mean particle diameter. The scope of applicability of the reconstructed Maxwell model is also discussed using the contact resistivity as a parameter.
HR Department
2006-01-01
Following discussion at TREF and on the recommendation of the Finance Committee, Council approved a new staff contract policy, which became effective on 1 January 2006. Its application is covered by a new Administrative Circular No. 2 (Rev. 3) 'Recruitment, appointment and possible developments regarding the contractual position of staff members'. The revised circular replaces the previous Circulars No. 9 (Rev. 3) 'Staff contracts' and No. 2 (Rev. 2) 'Guidelines and procedures concerning recruitment and probation period for staff members'. The main features of the new contract policy are as follows: The new policy provides chances for long-term employment for all staff recruits staying for four years without distinguishing between those assigned to long-term or short-term activities when joining CERN. In addition, it presents a number of simplifications for the award of ICs. There are henceforth only 2 types of contract: Limited Duration (LD) contracts for all recruitment and Indefinite Contracts (IC) for...
Unsteady flow of a Maxwell fluid over a stretching surface in presence of chemical reaction
Directory of Open Access Journals (Sweden)
Swati Mukhopadhyay
2012-10-01
Full Text Available An analysis is presented for unsteady two-dimensional flow of a Maxwell fluid over a stretching surface in presence of a first order constructive/destructive chemical reaction. Using suitable transformations, the governing partial differential equations are converted to ordinary one and are then solved numerically by shooting method. The flow fields and mass transfer are significantly influenced by the governing parameters. Fluid velocity initially decreases with increasing unsteadiness parameter and concentration decreases significantly due to unsteadiness. The effect of increasing values of the Maxwell parameter is to suppress the velocity field. But the concentration is enhanced with increasing Maxwell parameter.
Kumaran, G.; Sandeep, N.; Ali, M. E.
This paper reports the magnetohydrodynamic chemically reacting Casson and Maxwell fluids past a stretching sheet with cross diffusion, non-uniform heat source/sink, thermophoresis and Brownian motion effects. Numerical results are obtained by employing the R-K based shooting method. Effects of pertinent parameters on flow, thermal and concentration fields are discussed with graphical illustrations. We presented the tabular results to discuss the nature of the skin friction coefficient, reduced Nusselt and Sherwood numbers. Dual nature is observed in the solution of Casson and Maxwell fluids. It is also observed a significant increase in heat and mass transfer rate of Maxwell fluid when compared with the Casson fluid.
Staff Association
2013-01-01
Elections to fill all seats in the Staff Council are being organized this month. The voting takes place from the 28 of October to the 11th of November, at noon. As you may have noted when reading Echo, many issues concerning our employment conditions are on the agenda of the coming months, and in particular the Five-yearly-Review 2015, subject of the questionnaire that you probably recently filled out. All this will keep the next Staff Council very busy indeed. So, make your voice heard and take part in the elections for a new Staff Council. By doing so, you will be encouraging the men and women who will be representing you over the next two years and they will doubtless appreciate your gratitude. Every member of the Staff Association will have received an email containing a link to the webpage which will allow voting. If you are a member of the Staff Association and you did not receive such an email, please contact the Staff Association secretariat (staff.association@cern.ch). Do not forget to v...
Colles wrist fracture - aftercare
... replace the broken piece with a metal part Self-care at Home To help with pain and swelling: ... therapy. You should start working with a physical therapist as soon as your provider recommends. The work ...
Directory of Open Access Journals (Sweden)
G. Kumaran
Full Text Available This paper reports the magnetohydrodynamic chemically reacting Casson and Maxwell fluids past a stretching sheet with cross diffusion, non-uniform heat source/sink, thermophoresis and Brownian motion effects. Numerical results are obtained by employing the R-K based shooting method. Effects of pertinent parameters on flow, thermal and concentration fields are discussed with graphical illustrations. We presented the tabular results to discuss the nature of the skin friction coefficient, reduced Nusselt and Sherwood numbers. Dual nature is observed in the solution of Casson and Maxwell fluids. It is also observed a significant increase in heat and mass transfer rate of Maxwell fluid when compared with the Casson fluid. Keywords: Chemical reaction, Casson fluid, Maxwell fluid, Magnetohydrodynamic (MHD, Stretching sheet, Soret and Dufour effect
Pseudo spectral collocation with Maxwell polynomials for kinetic equations with energy diffusion
Sánchez-Vizuet, Tonatiuh; Cerfon, Antoine J.
2018-02-01
We study the approximation and stability properties of a recently popularized discretization strategy for the speed variable in kinetic equations, based on pseudo-spectral collocation on a grid defined by the zeros of a non-standard family of orthogonal polynomials called Maxwell polynomials. Taking a one-dimensional equation describing energy diffusion due to Fokker–Planck collisions with a Maxwell–Boltzmann background distribution as the test bench for the performance of the scheme, we find that Maxwell based discretizations outperform other commonly used schemes in most situations, often by orders of magnitude. This provides a strong motivation for their use in high-dimensional gyrokinetic simulations. However, we also show that Maxwell based schemes are subject to a non-modal time stepping instability in their most straightforward implementation, so that special care must be given to the discrete representation of the linear operators in order to benefit from the advantages provided by Maxwell polynomials.
Propagation of ultra-short solitons in stochastic Maxwell's equations
Energy Technology Data Exchange (ETDEWEB)
Kurt, Levent, E-mail: LKurt@gc.cuny.edu [Department of Science, Borough of Manhattan Community College, City University of New York, New York, New York 10007 (United States); Schäfer, Tobias [Department of Mathematics, College of Staten Island, City University of New York, Staten Island, New York 10314 (United States)
2014-01-15
We study the propagation of ultra-short short solitons in a cubic nonlinear medium modeled by nonlinear Maxwell's equations with stochastic variations of media. We consider three cases: variations of (a) the dispersion, (b) the phase velocity, (c) the nonlinear coefficient. Using a modified multi-scale expansion for stochastic systems, we derive new stochastic generalizations of the short pulse equation that approximate the solutions of stochastic nonlinear Maxwell's equations. Numerical simulations show that soliton solutions of the short pulse equation propagate stably in stochastic nonlinear Maxwell's equations and that the generalized stochastic short pulse equations approximate the solutions to the stochastic Maxwell's equations over the distances under consideration. This holds for both a pathwise comparison of the stochastic equations as well as for a comparison of the resulting probability densities.
Electricity and magnetism for mathematicians a guided path from Maxwell to Yang-Mills
Garrity, Thomas A
2015-01-01
This text is an introduction to some of the mathematical wonders of Maxwell's equations. These equations led to the prediction of radio waves, the realization that light is a type of electromagnetic wave, and the discovery of the special theory of relativity. In fact, almost all current descriptions of the fundamental laws of the universe can be viewed as deep generalizations of Maxwell's equations. Even more surprising is that these equations and their generalizations have led to some of the most important mathematical discoveries of the past thirty years. It seems that the mathematics behind Maxwell's equations is endless. The goal of this book is to explain to mathematicians the underlying physics behind electricity and magnetism and to show their connections to mathematics. Starting with Maxwell's equations, the reader is led to such topics as the special theory of relativity, differential forms, quantum mechanics, manifolds, tangent bundles, connections, and curvature.
The Maxwell-Chern-Simons gravity, and its cosmological implications
Energy Technology Data Exchange (ETDEWEB)
Haghani, Zahra; Shahidi, Shahab [Damghan University, School of Physics, Damghan (Iran, Islamic Republic of); Harko, Tiberiu [Babes-Bolyai University, Department of Physics, Cluj-Napoca (Romania); University College London, Department of Mathematics, London (United Kingdom)
2017-08-15
We consider the cosmological implications of a gravitational theory containing two vector fields coupled via a generalized Chern-Simons term. One of the vector fields is the usual Maxwell field, while the other is a constrained vector field with constant norm included in the action via a Lagrange multiplier. The theory admits a de Sitter type solution, with healthy cosmological perturbations. We also show that there are seven degrees of freedom that propagate on top of de Sitter space-time, consisting of two tensor polarizations, four degrees of freedom related to the two vector fields, and a scalar degree of freedom that makes one of the vector fields massive. We investigate the cosmological evolution of Bianchi type I space-time, by assuming that the matter content of the Universe can be described by the stiff and dust. The cosmological evolution of the Bianchi type I Universe strongly depends on the initial conditions of the physical quantities, as well as on the model parameters. The mean anisotropy parameter, and the deceleration parameter, are also studied, and we show that independently of the matter equation of state the cosmological evolution of the Bianchi type I Universe always ends in an isotropic de Sitter type phase. (orig.)
Spherically symmetric static solutions of the Einstein-Maxwell equations
International Nuclear Information System (INIS)
Krishna Rao, J.; Trivedi, M.M.
1998-01-01
We report a new formalism to obtain solutions of Einstein-Maxwell's equations for static spheres assuming the matter content to be a charged perfect fluid of null-conductivity. Defining three new variables u = 4 4πΕr 2 , v= 4πpr 2 and w= (4π/3)(ρ+ε)r 2 where Ε, ρ and ε denote respectively energy densities of the electric, matter and free gravitational fields whereas p is the fluid pressure, Einstein's field equations are rewritten in an elegant form. The solutions given are all shown to possess simple relations between u, v and w. Another solution for which all the three functions, u, v and w are constants is a trivial case of the present formalism. We have presented six new solutions with ε= 2ρ. For the first three solutions w and u are constants with v as a variable whereas the remaining three solutions satisfy the equation of state for isothermal gas; v=kw=-ku where: i) k is an arbitrary constant but not equal to 1 or 1/3, ii) k= 1 and iii) k= 1/3. We also obtained a generalization of Cooperstock and De la Cruz's solution which is regular for 2ρ > ε but singular for 2ρ ≤ ε. (author)
Phantom wormholes in Einstein–Maxwell-dilaton theory
Goulart, Prieslei
2018-01-01
In this paper we give an electrically charged traversable wormhole solution for the Einstein–Maxwell-dilaton theory when the dilaton is a phantom field, i.e. it has flipped sign kinetic term appearing in the action. In the limit when the charge is zero, we recover the anti-Fisher solution, which can be reduced to the Bronnikov–Ellis solution under certain choices of integration constants. The equations of motion of this theory share the same S-duality invariance of string theory, so the electrically charged solution is rotated into the magnetically charged one by applying such transformations. The scalar field is topological, so we compute its topological charge, and discuss that under appropriate boundary conditions we can have a lump, a kink, or an anti-kink profile. We determine the position of the throat, and show the embedding diagram of the wormhole. As a physical application, we apply the Gauss–Bonnet theorem to compute the deflection angle of a light-ray that passes close to the wormhole.
A New Observing Tool for the James Clerk Maxwell Telescope
Folger, Martin; Bridger, Alan; Dent, Bill; Kelly, Dennis; Adamson, Andy; Economou, Frossie; Hirst, Paul; Jenness, Tim
A new Observing Tool (OT) has been developed at the UK Astronomy Technology Centre, Edinburgh, UK and the Joint Astronomy Centre, Hilo, Hawaii, USA. It is based on the Gemini Observing Tool and provides the first graphical observation preparation tool for the James Clerk Maxwell Telescope (JCMT) as well as being the first use of the OT for a non-optical/IR telescope. The OT allows the observer to assemble high level Science Programs using graphical representations of observation components such as instrument, target, and filter. This is later translated into low level control sequences for telescope and instruments. The new OT is designed to work on multiple telescopes: currently the UK Infrared Telescope (UKIRT) and JCMT. Object-oriented design makes the inclusion of telescope and instrument specific packages easy. The OT is written in Java using GUI packages such as Swing and JSky. A new component for the JCMT OT is the graphical Frequency Editor for Heterodyne instruments. It can be used to specify parameters such as frequencies, bandwidths, and sidebands of multiple subsystems, while graphically displaying the front-end frequency, emission lines and atmospheric transmission. In addition, Flexible Scheduling support has been added to the OT. The observer can define scheduling constraints by arranging observations graphically. Science Programs can be saved as XML or sent directly from the OT to a database (via SOAP).
The Maxwell-Chern-Simons gravity, and its cosmological implications
Haghani, Zahra; Harko, Tiberiu; Shahidi, Shahab
2017-08-01
We consider the cosmological implications of a gravitational theory containing two vector fields coupled via a generalized Chern-Simons term. One of the vector fields is the usual Maxwell field, while the other is a constrained vector field with constant norm included in the action via a Lagrange multiplier. The theory admits a de Sitter type solution, with healthy cosmological perturbations. We also show that there are seven degrees of freedom that propagate on top of de Sitter space-time, consisting of two tensor polarizations, four degrees of freedom related to the two vector fields, and a scalar degree of freedom that makes one of the vector fields massive. We investigate the cosmological evolution of Bianchi type I space-time, by assuming that the matter content of the Universe can be described by the stiff and dust. The cosmological evolution of the Bianchi type I Universe strongly depends on the initial conditions of the physical quantities, as well as on the model parameters. The mean anisotropy parameter, and the deceleration parameter, are also studied, and we show that independently of the matter equation of state the cosmological evolution of the Bianchi type I Universe always ends in an isotropic de Sitter type phase.
Staff Association
2017-01-01
The Staff Association has been organising for many years a cocktail with delegates of the Member States participating in Finance Committees of March and September. This cocktail is held at the end of the day, after the Finance Committee meeting. This direct and regular communication helps establish an ongoing contact between the Staff Association and CERN Member States and, more recently, the Associate Member States. Ambassadors of the CERN Staff Association, who are Members of the Personnel, have the opportunity to meet their national delegation in an informal and friendly atmosphere. These exchanges, facilitated by the use of the national language, allow the personnel via the Staff Association to express its ideas and positions on current affairs and fundamental issues, and also to hear about those of the delegations in return.
HR Department
2007-01-01
The 11th edition of the Staff Rules and Regulations, dated 1 January 2007, adopted by the Council and the Finance Committee in December 2006, is currently being distributed to departmental secretariats. The Staff Rules and Regulations, together with a summary of the main modifications made, will be available, as from next week, on the Human Resources Department's intranet site: http://cern.ch/hr-web/internal/admin_services/rules/default.asp The main changes made to the Staff Rules and Regulations stem from the five-yearly review of employment conditions of members of the personnel. The changes notably relate to: the categories of members of the personnel (e.g. removal of the local staff category); the careers structure and the merit recognition system; the non-residence, installation and re-installation allowances; the definition of family, family allowances and family-related leave; recognition of partnerships; education fees. The administrative circulars, some of which are being revised following the ...
Construction of a new waste-water treatment plant, building 676, route Maxwell
TS Department
2008-01-01
A new waste-water treatment plant is being constructed on Route Maxwell to treat the effluents from the TS/MME/CCS surface treatment workshops. For this purpose, excavation work is being performed in two separate locations along Route Maxwell, causing a slight disruption to traffic in these areas. Site access through Gate C should, however, be maintained. The work is scheduled to continue until February 2009.
Two-Potential Formalism for Numerical Solution of the Maxwell Equations
Kudryavtsev, Alexey N.; Trashkeev, Sergey I.
2012-01-01
A new formulation of the Maxwell equations based on two vector and two scalar potentials is proposed. The use of these potentials allows the electromagnetic field equations to be written in the form of a hyperbolic system. In contrast to the original Maxwell equations, this system contains only evolutionary equations and does not include equations having the character of differential constraints. This fact makes the new equations especially convenient for numerical simulations of electromagne...
Electron-electron attractive interaction in Maxwell-Chern-Simons QED3 at zero temperature
International Nuclear Information System (INIS)
Belich, H.; Ferreira Junior, M.M.; Helayel-Neto, J.A.; Ferreira Junior, M.M.
2001-04-01
One discusses the issue of low-energy electron-electron bound states in the Maxwell-Chern-Simons model coupled to QED 3 with spontaneous breaking of a local U(1)-symmetry. The scattering potential, in the non-relativistic limit, steaming from the electron-electron Moeller scattering, mediated by the Maxwell-Chern-Simons-Proca gauge field and the Higgs scalar, might be attractive by fine-tuning properly the physical parameters of the model. (author)
Construction of a new wastewater treatment plant, building 676, route Maxwell
SC Unit
2008-01-01
A new wastewater treatment plant is being constructed on Route Maxwell to treat the effluents from the TS/MME/CCS surface treatment workshops. For this purpose, excavation work is being performed in two separate locations along Route Maxwell, causing a slight disruption to traffic in these areas. Site access through Gate C should, however, be maintained. The work is scheduled to continue through until February 2009.
No static bubbling spacetimes in higher dimensional Einstein–Maxwell theory
Kunduri, Hari K.; Lucietti, James
2018-03-01
We prove that any asymptotically flat static spacetime in higher dimensional Einstein–Maxwell theory must have no magnetic field. This implies that there are no static soliton spacetimes and completes the classification of static non-extremal black holes in this theory. In particular, these results establish that there are no asymptotically flat static spacetimes with non-trivial topology, with or without a black hole, in Einstein–Maxwell theory.
Directory of Open Access Journals (Sweden)
Cusack SL
2012-06-01
Full Text Available Susan L Cusack,1 Mark Jaros,2 Michael Kuss,3 Harold S Minkowitz,4 Peter Winkle,5 Lisa Hemsen61Cusack Pharmaceutical Consulting, Burlington, NJ, 2Summit Analytical, Denver, CO, USA; 3Premier Research Group, Austin, TX, USA; 4Memorial Hermann Memorial City Medical Center, Houston, TX, USA; 5Advanced Clinical Research Institute, Anaheim, CA, USA; 6Innocoll Technologies, Athlone, IrelandBackground: XaraColl®, a collagen-based implant that delivers bupivacaine to the site of surgical trauma, is under development for postoperative analgesia. Because of differing patient attitudes to postoperative pain control and the inability to assess baseline pain, standard clinical methods for evaluating analgesic efficacy are compromised and justify application of novel integrated approaches.Methods: We conducted two independent, multicenter, double-blind, placebo-controlled studies in men undergoing unilateral inguinal hernioplasty by open laparotomy to evaluate the safety and efficacy of XaraColl at different doses (100 mg and 200 mg of bupivacaine hydrochloride; study 1 and 2, respectively. Enrolled patients (50 in study 1 and 53 in study 2 were randomized to receive active or placebo implants in a 1:1 ratio. Postoperative pain intensity and use of supplementary opioid medication were recorded through 72 hours. Safety was assessed through 30 days. The principal efficacy variables were the summed pain intensity (SPI, total use of opioid analgesia (TOpA, and an integrated endpoint (I-SPI-TOpA. Each variable was analyzed at 24, 48, and 72 hours after implantation. A pooled analysis of both studies was also performed retrospectively.Results: Through 24 and 48 hours, XaraColl-treated patients experienced significantly less pain in study 1 (P < 0.001 and P = 0.012, respectively whereas they took significantly less opioid analgesia in study 2 (P = 0.004 and P = 0.042, respectively. Over the same time intervals in the pooled analysis, treated patients experienced
An enhanced vector diagram of Maxwell's equations for chiral media
Directory of Open Access Journals (Sweden)
Carlos Villarroel González
2012-01-01
Full Text Available En este trabajo se deriva un diagrama de las ecuaciones de Maxwell, en medios homogéneos isotrópicos, tal que pueda incluir un medio quiral. Este diagrama puede ser utilizado para obtener las relaciones entre campos, potenciales y fuentes, relacionando en forma adecuada las componentes vectoriales presentes en el diagrama. La construcción de este diagrama está basada en la similitud formal entre muchos teoremas del cálculo vectorial y aquellos del algebra vectorial. Se explica, en detalle, la construcción del diagrama para dos diferentes calibres, el de Lorentz y el de Coulomb, y se presentan algunas ecuaciones que pueden ser obtenidas del diagrama. En este trabajo, este enfoque, se aplica al cálculo numérico bidimensional de dos láminas quiral. Este trabajo puede ser una herramienta posible de usar en el diseño de dispositivos utilizados en sistemas de comunicaciones inalámbricas, en el rango espectral desde 1 GHz hasta aproximadamente 60 GHz, por ejemplo duplexores basados en divisores de potencia y filtraje posterior de frecuencia, utilizando SRR/CSRR (resonador de anillos divisores/ celdas coplanares SSR. Los dispositivos de circuito que utilizan SRR/CSRR tienen un tamaño muy pequeño, debido a que operan en sistemas sub-lambda. Este trabajo también puede ser útil para el análisis del diseño, entre otros, de parches impresos para la banda S y para la discusión de diferentes tipos de filtros y otros dispositivos que utilicen metamateriales y guías de onda coplanares.
`Number States' and `Pilot Waves' Hidden in Maxwell's Classical Equations
Carroll, John E.
2010-12-01
Schrödingers equation with boundary conditions gives quantized energy states for electron waves, but Maxwell's wave equations have quantized states only by analogies with harmonic oscillators. This problem is addressed by a novel theory of wave-packets using diffracting Transverse Electric and Transverse Magnetic fields defined by axial H- and E-fields. All transverse fields and gradient operators can together be rotated about the propagation axis at frequencies, independent of the modal frequency. Without altering the axial fields, any helical motion propagates at the group velocity. This is quite different from single frequency helical modes (e.g. Laguerre Gaussian) travelling at the phase velocity. Reversing time and frequency, allows counter rotating helical solutions. These are referred to as adjoint or a fields that may interact and propagate with the classical causal reference or r fields. Overlapping and counter rotating r and a fields with slightly different frequencies interfere, leaving circular polarization states unaltered and creating a nodal structure in the transverse fields distinct from the nodal structure in the axial fields. Number states arise from requiring that transverse and axial nodes co-locate with integral spacings to form a wave-packet,. The a fields act as pilot waves for future potential positions of a quantized interaction between r and a fields. Uncertainty in the position of the overlap leads to conventional probabilistic quantum interpretations. The a fields are not fully determined until their detection with the r wave and this late determination can offer explanations for non-local entanglement.
Non-deteriorating time domain numerical algorithms for Maxwell's electrodynamics
Petropavlovsky, S.; Tsynkov, S.
2017-05-01
The Huygens' principle and lacunae can help construct efficient far-field closures for the numerical simulation of unsteady waves propagating over unbounded regions. Those closures can be either standalone or combined with other techniques for the treatment of artificial outer boundaries. A standalone lacunae-based closure can be thought of as a special artificial boundary condition (ABC) that is provably free from any error associated with the domain truncation. If combined with a different type of ABC or a perfectly matched layer (PML), a lacunae-based approach can help remove any long-time deterioration (e.g., instability) that arises at the outer boundary regardless of why it occurs in the first place. A specific difficulty associated with Maxwell's equations of electromagnetism is that in general their solutions do not have classical lacunae and rather have quasi-lacunae. Unlike in the classical case, the field inside the quasi-lacunae is not zero; instead, there is an electrostatic solution driven by the electric charges that accumulate over time. In our previous work [23], we have shown that quasi-lacunae can also be used for building the far-field closures. However, for achieving a provably non-deteriorating performance over arbitrarily long time intervals, the accumulated charges need to be known ahead of time. The main contribution of the current paper is that we remove this limitation and modify the algorithm in such a way that one can rather avoid the accumulation of charge all together. Accordingly, the field inside the quasi-lacunae becomes equal to zero, which facilitates obtaining the temporally uniform error estimates as in the case of classical lacunae. The performance of the modified algorithm is corroborated by a series of numerical simulations. The range of problems that the new method can address includes important combined formulations, for which the interior subproblem may be non-Huygens', and only the exterior subproblem, i.e., the far
Language Individuation and Marker Words: Shakespeare and His Maxwell's Demon.
Directory of Open Access Journals (Sweden)
John Marsden
Full Text Available Within the structural and grammatical bounds of a common language, all authors develop their own distinctive writing styles. Whether the relative occurrence of common words can be measured to produce accurate models of authorship is of particular interest. This work introduces a new score that helps to highlight such variations in word occurrence, and is applied to produce models of authorship of a large group of plays from the Shakespearean era.A text corpus containing 55,055 unique words was generated from 168 plays from the Shakespearean era (16th and 17th centuries of undisputed authorship. A new score, CM1, is introduced to measure variation patterns based on the frequency of occurrence of each word for the authors John Fletcher, Ben Jonson, Thomas Middleton and William Shakespeare, compared to the rest of the authors in the study (which provides a reference of relative word usage at that time. A total of 50 WEKA methods were applied for Fletcher, Jonson and Middleton, to identify those which were able to produce models yielding over 90% classification accuracy. This ensemble of WEKA methods was then applied to model Shakespearean authorship across all 168 plays, yielding a Matthews' correlation coefficient (MCC performance of over 90%. Furthermore, the best model yielded an MCC of 99%.Our results suggest that different authors, while adhering to the structural and grammatical bounds of a common language, develop measurably distinct styles by the tendency to over-utilise or avoid particular common words and phrasings. Considering language and the potential of words as an abstract chaotic system with a high entropy, similarities can be drawn to the Maxwell's Demon thought experiment; authors subconsciously favour or filter certain words, modifying the probability profile in ways that could reflect their individuality and style.
Stochastic Levy Laplacian and d'Alambertian and Maxwell's equations
Directory of Open Access Journals (Sweden)
B. O. Volkov
2015-01-01
Full Text Available One of the main reasons for interest in the Levy Laplacian and its analogues such as Levy d'Alembertian is a connection of these operators with gauge fields. The theorem proved by Accardi, Gibillisco and Volovich stated that a connection in a bundle over a Euclidean space or over a Minkowski space is a solution of the Yang-Mills equations if and only if the corresponding parallel transport to the connection is a solution of the Laplace equation for the Levy Laplacian or of the d'Alembert equation for the Levy d'Alembertian respectively (see [5, 6]. There are two approaches to define Levy type operators, both of which date back to the original works of Levy (see [7]. The first is that the Levy Laplacian (or Levy d'Alembertian is defined as an integral functional generated by a special form of the second derivative. This approach is used in the works [5, 6], as well as in the paper [8] of Leandre and Volovich, where stochastic Levy-Laplacian is discussed. Another approach to the Levy Laplacian is defining it as the Cesaro mean of second order derivatives along the family of vectors, which is an orthonormal basis in the Hilbert space. This definition of the Levy Laplacian is used for the description of solutions of the Yang-Mills equations in the paper [10].The present work shows that the definitions of the Levy Laplacian and the Levy d'Alembertian based on Cesaro averaging of the second order directional derivatives can be transferred to the stochastic case. In the article the values of these operators on a stochastic parallel transport associated with a connection (vector potential are found. In this case, unlike the deterministic case and the stochastic case of Levy Laplacian from [8], these values are not equal to zero if the vector potential corresponding to the stochastic parallel transport is a solution of the Maxwell's equations. As a result, two approaches to definition of the Levy Laplacian in the stochastic case give different operators
CERN PhotoLab
1965-01-01
An example of the integration of CERN staff in the neighbouring communes is provided by the hamlet of Bugnon at St-Genis-Pouilly (Ain), FRance. The CERN installation on the Swiss site are visible on the left in the background. Behind them the Saleve mountain in Haute-Savoie.
HR Department
2007-01-01
The 11th edition of the Staff Rules and Regulations, dated 1 January 2007, adopted by the Council and the Finance Committee in December 2006, is currently being distributed to departmental secretariats. The Staff Rules and Regulations, together with a summary of the main modifications made, will be available, as from next week, on the Human Resources Department's intranet site: http://cern.ch/hr-web/internal/admin_services/rules/default.asp The main changes made to the Staff Rules and Regulations stem from the five-yearly review of employment conditions of members of the personnel. The changes notably relate to: the categories of members of the personnel (e.g. removal of the local staff category); the careers structure and the merit recognition system; the non-residence, installation and re-installation allowances; the definition of family, family allowances and family-related leave; recognition of partnerships; education fees. The administrative circulars, some of which are being revised following the m...
Murphy, Norman L.
1979-01-01
Describes the process of staff selection for the general studies department at Piedmont Technical College. Makes suggestions on how to write a job description, establish selection criteria, develop the selection process, and make the selection itself. Includes sample forms used in the process. (DR)
Jones, Rebecca
1994-01-01
Some children have chronic illnesses that require diet modifications as part of their medical treatment. Advises school districts to hire a registered dietitian or look for resources at a local hospital or public health office. In addition, schools should work with parents, improve staff training, and conduct spot checks of school cafeterias. (MLF)
On Understanding: Maxwell on the Methods of Illustration and Scientific Metaphor
Cat, Jordi
In this paper I examine the notion and role of metaphors and illustrations in Maxwell's works in exact science as a pathway into a broader and richer philosophical conception of a scientist and scientific practice. While some of these notions and methods are still at work in current scientific research-from economics and biology to quantum computation and quantum field theory-, here I have chosen to attest to their entrenchment and complexity in actual science by attempting to make some conceptual sense of Maxwell's own usage; this endeavour includes situating Maxwell's conceptions and applications in his own culture of Victorian science and philosophy. I trace Maxwell's notions to the formulation of the problem of understanding, or interpreting, abstract representations such as potential functions and Lagrangian equations. I articulate the solution in terms of abstract-concrete relations, where the concrete, in tune with Victorian British psychology and engineering, includes the muscular as well as the pictorial. This sets the basis for a conception of understanding in terms of unification and concrete modelling, or representation. I examine the relation of illustration to analogies and metaphors on which this account rests. Lastly, I stress and explain the importance of context-dependence, its consequences for realism-instrumentalism debates, and Maxwell's own emphasis on method.
La unificación electromagnética: 150 aniversario de las ecuaciones de Maxwell
Beléndez Vázquez, Augusto
2015-01-01
En este artículo, publicado en la revista Mètode (revista de difusión de la investigación de la Universidad de Valencia) se recuerda que en el año 2015 se celebra el ciento cincuenta aniversario de las ecuaciones de Maxwell, pues en 1865 Maxwell publicó el artículo "Una teoría dinámica del campo electromagnético" que contenía las ecuaciones de Maxwell, la predicción teórica de la existencia de las ondas electromagnéticas y la teoría electromagnética de la luz. En el artículo también se hace r...
Goorjian, Peter M.; Silberberg, Yaron; Kwak, Dochan (Technical Monitor)
1995-01-01
This paper will present results in computational nonlinear optics. An algorithm will be described that solves the full vector nonlinear Maxwell's equations exactly without the approximations that we currently made. Present methods solve a reduced scalar wave equation, namely the nonlinear Schrodinger equation, and neglect the optical carrier. Also, results will be shown of calculations of 2-D electromagnetic nonlinear waves computed by directly integrating in time the nonlinear vector Maxwell's equations. The results will include simulations of 'light bullet' like pulses. Here diffraction and dispersion will be counteracted by nonlinear effects. The time integration efficiently implements linear and nonlinear convolutions for the electric polarization, and can take into account such quantum effects as Karr and Raman interactions. The present approach is robust and should permit modeling 2-D and 3-D optical soliton propagation, scattering, and switching directly from the full-vector Maxwell's equations.
Resolution of unsteady Maxwell equations with charges in non convex domains
International Nuclear Information System (INIS)
Garcia, Emmanuelle
2002-01-01
This research thesis deals with the modelling and numerical resolution of problems related to plasma physics. The interaction of charged particles (electrons and ions) with electromagnetic fields is modelled with the system of unsteady Vlasov-Maxwell coupled equations (the Vlasov system describes the transport of charged particles and the Maxwell equations describe the wave propagation). The author presents definitions related to singular domains, establishes a Helmholtz decomposition in a space of electro-magnetostatic solutions. He reports a mathematical analysis of decompositions into a regular and a singular part of general functional spaces intervening in the investigation of the Maxwell system in complex geometries. The method is then implemented for bi-dimensional domains. A last part addressed the study and the numerical resolution of three-dimensional problems
Lowther, D A; Freeman, E M
2008-05-28
Faraday's work inspired the development of electrical motors and generators. Until Maxwell pointed out the significance of Ampere's Law, there was no rigorous design method for magnetic devices. His interpretation strongly influenced the creation, by others, of the 'magnetic circuit' approach, which became the seminal design technique. This, utilizing the concept of reluctance, led to the design method for magnetic machines that is still widely in use today. The direct solution of the Maxwell equations (less the displacement current term) had to await the development of modern continuum methods to yield the field everywhere in, and around, the devices of interest, and this then permitted the application of the Maxwell stress tensor. This final refinement yielded forces and torques, and this resulted in the accurate prediction of electrical machine performance.
Effects of backreaction on power-Maxwell holographic superconductors in Gauss-Bonnet gravity
Energy Technology Data Exchange (ETDEWEB)
Salahi, Hamid Reza; Montakhab, Afshin [Shiraz University, Physics Department and Biruni Observatory, College of Sciences, Shiraz (Iran, Islamic Republic of); Sheykhi, Ahmad [Shiraz University, Physics Department and Biruni Observatory, College of Sciences, Shiraz (Iran, Islamic Republic of); Research Institute for Astronomy and Astrophysics of Maragha (RIAAM), P.O. Box 55134-441, Maragha (Iran, Islamic Republic of)
2016-10-15
We analytically and numerically investigate the properties of s-wave holographic superconductors by considering the effects of scalar and gauge fields on the background geometry in five-dimensional Einstein-Gauss-Bonnet gravity. We assume the gauge field to be in the form of the power-Maxwell nonlinear electrodynamics. We employ the Sturm-Liouville eigenvalue problem for analytical calculation of the critical temperature and the shooting method for the numerical investigation. Our numerical and analytical results indicate that higher curvature corrections affect condensation of the holographic superconductors with backreaction. We observe that the backreaction can decrease the critical temperature of the holographic superconductors, while the power-Maxwell electrodynamics and Gauss-Bonnet coefficient term may increase the critical temperature of the holographic superconductors. We find that the critical exponent has the mean-field value β = 1/2, regardless of the values of Gauss-Bonnet coefficient, backreaction and power-Maxwell parameters. (orig.)
Directory of Open Access Journals (Sweden)
Chantal Leclerc
2005-05-01
Full Text Available La prévention du harcèlement psychologique au travail passe par la compréhension des formes qu’il prend selon les milieux et les contextes organisationnels dans lesquels il émerge. Une recherche auprès de professeures et professeurs d’universités révèle que le harcèlement prend racine dans une culture universitaire qui instaure la surcharge, la compétition, l’individualisme, le blocage des règles de la délibération et le culte de la performance comme modes de gestion et d’organisation du travail. Fait troublant : les moyens utilisés pour accabler, détruire ou asservir sont les instruments même de la collégialité qui sont détournés, les pouvoirs formels ou informels de recommandation, d’évaluation, de décision dont on abuse et la manipulation des collègues ainsi que des étudiantes et étudiants qu’on réussit à faire taire ou à liguer contre une personne ou un groupe. Les atteintes à l’expression, à la communication, à la réputation et aux conditions de travail constituent les moyens les plus fréquemment cités de violence psychologique. Elles sont possibles et leurs conséquences sont aggravées par l’inaction des collègues, la passivité de l’administration, mais aussi par l’attitude frileuse de syndicats qui hésitent parfois à intervenir.Preventing psychological harassment in the workplace requires an understanding of the forms it takes in the organizational environments and contexts in which it appears. A study of university professors indicates that harassment takes root in a university culture that establishes extra work responsibilities, competition, individualism, eliminates discussion and glorifies performance as management styles and modes of work organization. One troubling fact: the means used to overwhelm, destroy or subdue are the very instruments of collegiality that are diverted; the formal or informal powers of recommendation, appraisal and decision-making are abused; and
DEFF Research Database (Denmark)
Pessah, Martin Elias; Chan, Chi-kwan; Psaltis, Dimitrios
2006-01-01
The magnetorotational instability is thought to be responsible for the generation of magnetohydrodynamic turbulence that leads to enhanced outward angular momentum transport in accretion discs. Here, we present the first formal analytical proof showing that, during the exponential growth...... of the instability, the mean (averaged over the disc scale-height) Reynolds stress is always positive, the mean Maxwell stress is always negative, and hence the mean total stress is positive and leads to a net outward flux of angular momentum. More importantly, we show that the ratio of the Maxwell to the Reynolds...
Stationary solutions of the Maxwell-Dirac and the Klein-Gordon-Dirac equations
International Nuclear Information System (INIS)
Esteban, M.J.; Georgiev, V.; Sere, E.
1995-01-01
The Maxwell-Dirac system describes the interaction of an electron with its own electromagnetic field. We prove the existence of soliton-like solutions of Maxwell-Dirac in (3+1)-Minkowski space-time. The solutions obtained are regular, stationary in time, and localized in space. They are found by a variational method, as critical points of an energy functional. This functional is strongly indefinite and presents a lack of compactness. We also find soliton-like solutions for the Klein-Gordon-Dirac system, arising in the Yukawa model. (author). 32 refs
Exact helicoidal and catenoidal solutions in five- and higher-dimensional Einstein-Maxwell theory
Ghezelbash, A. M.; Kumar, V.
2017-06-01
We present several new exact solutions in five- and higher-dimensional Einstein-Maxwell theory by embedding the Nutku instanton. The metric functions for the five-dimensional solutions depend only on a radial coordinate and on two spatial coordinates for the six- and higher-dimensional solutions. The six- and higher-dimensional metric functions are convolutedlike integrals of two special functions. We find that the solutions are regular almost everywhere and some spatial sections of the solution describe wormhole handles. We also find a class of exact and nonstationary convolutedlike solutions to the Einstein-Maxwell theory with a cosmological constant.
A geometric formulation of Einstein Maxwell theory in Einstein-Cartan space-time
International Nuclear Information System (INIS)
Fonseca Neto, J.B. da; Rivelles, V.O.
1984-01-01
A geometric theory is proposed for electrogametism and gravitation where the electromagnetic potential is introduced in the geometry through the torsion. An is first built action for dyon electrodynamics using the two potentials formulation in such a way it is equivalent to Maxwell theory if the ratio between electric and magnetic charges is an universal constant. Since the torsion can be decomposed into a trace, a pseudo-trace and a traceless part, the two potentials of the dyon elctrodynamics with the two traces of the torsion are identified and an action which reproduces the Einstein-Maxwell theory: Matter fields do not have a propor minimal coupling to this theory. (Author) [pt
Voit, Florian; Schäfer, Jan; Kienle, Alwin
2009-09-01
We present a methodology to compare results of classical radiative transfer theory against exact solutions of Maxwell theory for a high number of spheres. We calculated light propagation in a cubic scattering region (20 x 20 x 20 microm(3)) consisting of different concentrations of polystyrene spheres in water (diameter 2 microm) by an analytical solution of Maxwell theory and by a numerical solution of radiative transfer theory. The relative deviation of differential as well as total scattering cross sections obtained by both approaches was evaluated for each sphere concentration. For the considered case, we found that deviations due to radiative transfer theory remain small, even for concentrations up to ca. 20 vol. %.
International Nuclear Information System (INIS)
Munz, C.D.; Schneider, R.; Stein, E.; Voss, U.; Westermann, T.; Krauss, M.
1996-01-01
The numerical concept realized in the the Karlsruhe Diode Code KADI2D is briefly reviewed. Several new aspects concerning the Maxwell field solver based on high resolution finite-volume methods are presented. A new approach maintaining charge conservation numerically for the Maxwell-Lorentz equations is shortly summarized. (author). 2 figs., 12 refs
2012-08-02
... Intent to Repatriate Cultural Items: Maxwell Museum of Anthropology, University of New Mexico... Anthropology, in consultation with the Pueblo of Santa Ana, New Mexico, has determined that a collection of... cultural affiliation with the cultural items should contact the Maxwell Museum of Anthropology at the...
International Nuclear Information System (INIS)
Konecny, L.; Vaclav, J.
2006-01-01
The Public Notice has constituted the details about requirements in the transport of radioactive material. The Public Notice has replaced the previous Public Notice of the Nuclear Regulatory Authority of the Slovak Republic No. 284/1999 Coll. about the details of transport of the nuclear material. The Public Notice has elaborated in the detailed form rights and duties of subjects participating in transport of the nuclear material as well as the technical terms for facilities used for transport. Recommendations of the International Agency for the Nuclear energy were included into the Public Notice. These recommendations are mentioned in its safety standard 'Regulations for the Safe Transport of Radioactive Material', edition 2003. Only those recommendations have been taken on which concern the transport of nuclear material, radioactive waste and nuclear fuel burnt-up. These recommendations have been created by the international group of experts under IAEA organisation. The group regularly updates the recommendations in accordance with the newest knowledge
NICU consultants and support staff
Newborn intensive care unit - consultants and support staff; Neonatal intensive care unit - consultants and support staff ... a baby's nipple-feeding readiness and oral-motor skills. Speech therapists will also help with feeding skills ...
Rauscher, Elizabeth A
2011-01-01
The Maxwell, Einstein, Schrödinger and Dirac equations are considered the most important equations in all of physics. This volume aims to provide new eight- and twelve-dimensional complex solutions to these equations for the first time in order to reveal
Chern-Simons and Born-Infeld gravity theories and Maxwell algebras type
International Nuclear Information System (INIS)
Concha, P.K.; Penafiel, D.M.; Rodriguez, E.K.; Salgado, P.
2014-01-01
Recently it was shown that standard odd- and even-dimensional general relativity can be obtained from a (2n + 1)-dimensional Chern-Simons Lagrangian invariant under the B 2n+1 algebra and from a (2n)-dimensional Born-Infeld Lagrangian invariant under a subalgebra L B 2n+1 , respectively. Very recently, it was shown that the generalized Inoenue-Wigner contraction of the generalized AdS-Maxwell algebras provides Maxwell algebras of types M m which correspond to the so-called B m Lie algebras. In this article we report on a simple model that suggests a mechanism by which standard odd-dimensional general relativity may emerge as the weak coupling constant limit of a (2p + 1)-dimensional Chern-Simons Lagrangian invariant under the Maxwell algebra type M 2m+1 , if and only if m ≥ p. Similarly, we show that standard even-dimensional general relativity emerges as the weak coupling constant limit of a (2p)-dimensional Born-Infeld type Lagrangian invariant under a subalgebra L M 2m of theMaxwell algebra type, if and only if m ≥ p. It is shown that when m 2m+1 and for a (2p)-dimensional Born-Infeld type Lagrangian invariant under the L M 2m algebra. (orig.)
On The Flow of Maxwell Fluid Between Two Walls Induced By A ...
African Journals Online (AJOL)
The flow of a Maxwell fluid between two side walls induced by a constant accelerating plate is revisited. In the present investigation, we employed asymptotic technique by assuming small and large relaxation times λ. We proved the uniqueness of our solution based on some simplifying assumption; the result shows that λ ...
The Chevreton tensor and Einstein-Maxwell spacetimes conformal to Einstein spaces
International Nuclear Information System (INIS)
Bergqvist, Goeran; Eriksson, Ingemar
2007-01-01
In this paper, we characterize the source-free Einstein-Maxwell spacetimes which have a trace-free Chevreton tensor. We show that this is equivalent to the Chevreton tensor being of pure radiation type and that it restricts the spacetimes to Petrov type N or O. We prove that the trace of the Chevreton tensor is related to the Bach tensor and use this to find all Einstein-Maxwell spacetimes with a zero cosmological constant that have a vanishing Bach tensor. Among these spacetimes we then look for those which are conformal to Einstein spaces. We find that the electromagnetic field and the Weyl tensor must be aligned, and in the case that the electromagnetic field is null, the spacetime must be conformally Ricci-flat and all such solutions are known. In the non-null case, since the general solution is not known on a closed form, we settle by giving the integrability conditions in the general case, but we do give new explicit examples of Einstein-Maxwell spacetimes that are conformal to Einstein spaces, and we also find examples where the vanishing of the Bach tensor does not imply that the spacetime is conformal to a C-space. The non-aligned Einstein-Maxwell spacetimes with vanishing Bach tensor are conformally C-spaces, but none of them are conformal to Einstein spaces
Multilevel iterative solvers for the edge finite element solution of the 3D Maxwell equation
Nechaev, O.V.; Shurina, E.P.; Bochev, Mikhail A.
2008-01-01
In the edge vector finite element solution of the frequency domain Maxwell equations, the presence of a large kernel of the discrete rotor operator is known to ruin convergence of standard iterative solvers. We extend the approach of [R. Hiptmair, Multigrid method for Maxwell’s equations, SIAM J.
Multilevel iterative solvers for the edge finite element solution of the 3D Maxwell equation
Nechaev, O.V.; Shurina, E.P.; Bochev, Mikhail A.
In the edge vector finite element solution of the frequency domain Maxwell equations, the presence of a large kernel of the discrete rotor operator is known to ruin convergence of standard iterative solvers. We extend the approach of [1] and, using domain decomposition ideas, construct a multilevel
Harutyunyan, D.; Izsak, F.; van der Vegt, Jacobus J.W.; Bochev, Mikhail A.
For the adaptive solution of the Maxwell equations on three-dimensional domains with N´ed´elec edge finite element methods, we consider an implicit a posteriori error estimation technique. On each element of the tessellation an equation for the error is formulated and solved with a properly chosen
On Bianchi-I cosmic strings coupled with Maxwell fields in bimetric ...
Indian Academy of Sciences (India)
Axially symmetric Bianchi-I model is studied with source cosmic cloud strings coupled with electromagnetic ﬁeld in Rosen's bimetric theory of relativity and observed that there is no contribution from cosmic strings and Maxwell ﬁelds in this theory.
Efficient time-stepping-free time integration of the Maxwell equations
Bochev, Mikhail A.; Brushlinskii, K.V.; Gavreeva, M.S.; Zhukov, V.T.; Severin, A.V.; Cmykhova, N.A.
Solution of the time dependent Maxwell equations is an important problem arising in many applications ranging from nanophotonics to geoscience and astronomy. The problem is far from trivial, and solutions typically exhibit complicated wave properties as well as damping behavior. Usually, special
Generalization of the Biot--Savart law to Maxwell's equations using special relativity
International Nuclear Information System (INIS)
Neuenschwander, D.E.; Turner, B.N.
1992-01-01
Maxwell's equations are obtained by generalizing the laws of magnetostatics, which follow from the Biot--Savart law and superposition, to be consistent with special relativity. The Lorentz force on a charged particle and its rate of energy change also follow by making Newton's second law for a particle in a magnetostatic field consistent with special relativity
International Nuclear Information System (INIS)
Silva, Rone Lemos da; Souza, Manoelito
2011-01-01
Full text: This work intends to show a brief introduction about tensor calculus and how they are considered, their connections with differential forms and the geometric algebra. To begin with, its a brief presentation of the concepts that involve the indicial notation with demonstration of some important equations of Mathematics and Physics. Actually, both fields will prove always the most simple, elegant and compact representation of mathematical entities. Indeed the approach presented here lends itself to this role, thus the power of representation of the indicial notation presented as an effective tool mathematical to serve the Physics. As an application example in Physics, Theory of Relativity and Maxwell Equations of Electromagnetic Theory are shown in a tensor formulation its showing how elegant and powerful is this approach. Maxwell's equations of electromagnetism, for instance, presents a reduced form, no less important, but only about the way they are written. Its also important to remember that once using the brief notation presented here, symmetry of Maxwell's equations generalization with the inclusion of magnetic monopoles is discussed, once the existence of these particles is consistent with Maxwell's equations, if the electric charges are quantized, which is observed. About the Theory of Relativity, is a fact that must be written in terms of tensors, thus defining a non-Euclidean space. (author)
Time-integration methods for finite element discretisations of the second-order Maxwell equation
Sarmany, D.; Bochev, Mikhail A.; van der Vegt, Jacobus J.W.
This article deals with time integration for the second-order Maxwell equations with possibly non-zero conductivity in the context of the discontinuous Galerkin finite element method (DG-FEM) and the H(curl)-conforming FEM. For the spatial discretisation, hierarchic H(curl)-conforming basis
Time-integration methods for finite element discretisations of the second-order Maxwell equation
Sarmany, D.; Bochev, Mikhail A.; van der Vegt, Jacobus J.W.
This article deals with time integration for the second-order Maxwell equations with possibly non-zero conductivity in the context of the discontinuous Galerkin finite element method DG-FEM) and the $H(\\mathrm{curl})$-conforming FEM. For the spatial discretisation, hierarchic
Lin, Kai; Yang, Shu-Zheng
2009-10-01
Fermions tunneling of the non-stationary Dilaton-Maxwell black hole is investigated with general tortoise coordinate transformation. The Dirac equation is simplified by semiclassical approximation so that the Hamilton-Jacobi equation is generated. Finally the tunneling rate and the Hawking temperature is calculated.
Regularity of the Maxwell equations in heterogeneous media and Lipschitz domains
Bonito, Andrea
2013-12-01
This note establishes regularity estimates for the solution of the Maxwell equations in Lipschitz domains with non-smooth coefficients and minimal regularity assumptions. The argumentation relies on elliptic regularity estimates for the Poisson problem with non-smooth coefficients. © 2013 Elsevier Ltd.
Holography for Einstein-Maxwell-dilaton theories from generalized dimensional reduction
Goutéraux, Blaise; Smolic, Jelena; Smolic, Milena; Skenderis, Kostas; Taylor, Marika
2012-01-01
We show that a class of Einstein-Maxwell-Dilaton (EMD) theories are re- lated to higher dimensional AdS-Maxwell gravity via a dimensional reduction over com- pact Einstein spaces combined with continuation in the dimension of the compact space to non-integral values (`generalized dimensional reduction'). This relates (fairly complicated) black hole solutions of EMD theories to simple black hole/brane solutions of AdS-Maxwell gravity and explains their properties. The generalized dimensional reduction is used to infer the holographic dictionary and the hydrodynamic behavior for this class of theories from those of AdS. As a specific example, we analyze the case of a black brane carrying a wave whose universal sector is described by gravity coupled to a Maxwell field and two neutral scalars. At thermal equilibrium and finite chemical potential the two operators dual to the bulk scalar fields acquire expectation values characterizing the breaking of con- formal and generalized conformal invariance. We compute holographically the first order transport coefficients (conductivity, shear and bulk viscosity) for this system.
International Nuclear Information System (INIS)
Portugal, R.; Soares, I.D.
1985-01-01
Two new classes of spatially homogeneous cosmological solutions of Einstein-Maxwell equations are obtained by considering a class of exact perturbations of the static Bertotti-Robinson (BR) model. The BR solution is shown to be unstable under these perturbations, being perturbed into exact cosmological solutions with perfect fluid (equations of state p = lambda rho, O [pt
Bonito, Andrea
2011-01-01
We propose and analyze an approximation technique for the Maxwell eigenvalue problem using H1-conforming finite elements. The key idea consists of considering a mixed method controlling the divergence of the electric field in a fractional Sobolev space H-α with α ∈ (1/2, 1). The method is shown to be convergent and spectrally correct. © 2011 American Mathematical Society.
New numerical methods for solving the time-dependent Maxwell equations
De Raedt, H; Kole, JS; Michielsen, KFL; Figge, MT; Berz, M; Makino, K
2005-01-01
We review some recent developments in numerical algorithms to solve the time-dependent Maxwell equations for systems with spatially varying permittivity and permeabilitly. We show that the Suzuki product-formula approach can be used to construct a family of unconditionally stable algorithms, the
A novel Lanczos-type procedure for computing eigenelements of Maxwell and Helmholtz problems
Carpentieri, B.; Jing, Y-F; Huang, T-Z
2010-01-01
We introduce a novel variant of the Lanczos method for computing a few eigenvalues of sparse and/or dense non-Hermitian systems arising from the discretization of Maxwell- or Helmholtz-type operators in electromagnetics. We develop a Krylov subspace projection technique built upon short-term vector
Czech Academy of Sciences Publication Activity Database
Niemann, R.; Heczko, Oleg; Schultz, L.; Fähler, S.
2014-01-01
Roč. 37, SI (2014), 281-288 ISSN 0140-7007 R&D Projects: GA ČR(CZ) GAP107/11/0391 Institutional support: RVO:68378271 Keywords : magnetocaloric * shape memory alloys * multiferroic * Ni-Mn-Ga * Maxwell relation Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.241, year: 2014
Solitary waves, steepening and initial collapse in the Maxwell-Lorentz system
DEFF Research Database (Denmark)
Sørensen, Mads Peter; Brio, Moysey; Webb, Garry
2002-01-01
We present a numerical study of Maxwell's equations in nonlinear dispersive optical media describing propagation of pulses in one Cartesian space dimension. Dispersion and nonlinearity are accounted for by a linear Lorentz model and an instantaneous Kerr nonlinearity, respectively. The dispersion......–Rosales weakly dispersive system. The weak dispersion in general cannot prevent the wave breaking with instantaneous or delayed nonlinearities....
Information for contractors' staff
The Dosimetry Service
2005-01-01
We have observed a significant decrease in the number of completed Certificates for Work in Controlled Radiation Areas being submitted with applications for dosimeters for your staff. Henceforth, we shall no longer be able to issue dosimeters without a certificate, which must be signed by the employee and the contractor's radiation-protection expert. You can obtain the certificate form from the Dosimetry Service at Building 24/E-011 or from our Website: http://service-rp-dosimetry.web.cern.ch/service-rp-dosimetry/. Thank you for your understanding. The Dosimetry Service
Human Resources Division
2002-01-01
For economy reasons, it has been decided to stop printing and distributing this list to Staff Members. It can be found on the Web (LIST). Divisional Administrative Officers will receive an updated printed copy on a monthly basis and are asked to display this in a public place in their division. Copies will also be posted on the notice boards of the Administration Building (No. 60) in the glass-fronted cabinet (close to the lifts) and also on the notice board close to the Post Office. A copy will also be given to the Reception (Building No. 33). Human Resources Division Tel. 74606
Association du personnel
2013-01-01
The Staff Association, your representative with the Management and the Member States The article VII 1.01 of the Staff Rules and Regulations (SR&R) provides that “the relations between the Director-General and the personnel shall be established either on an individual basis or on a collective basis with the Staff Association as intermediary”. This essential role of the Staff representatives, of being the spokesperson of the entire staff of the Organization vis-à-vis the Director-General and the Members States, is achieved through regular participation in the various joint advisory committees defined in the SR&R. The most important are the Standing Concertation Committee and the TREF, tripartite forum where your representatives meet with the Member States delegates, in the presence of the Management, to explain the position of the staff on the various issues concerning employment conditions. The Finance Committee also gives the opportunity to the Staff Association to ...
Improving staff selection processes.
Cerinus, Marie; Shannon, Marina
2014-11-11
This article, the second in a series of articles on Leading Better Care, describes the actions undertaken in recent years in NHS Lanarkshire to improve selection processes for nursing, midwifery and allied health professional (NMAHP) posts. This is an area of significant interest to these professions, management colleagues and patients given the pivotal importance of NMAHPs to patient care and experience. In recent times the importance of selecting staff not only with the right qualifications but also with the right attributes has been highlighted to ensure patients are well cared for in a safe, effective and compassionate manner. The article focuses on NMAHP selection processes, tracking local, collaborative development work undertaken to date. It presents an overview of some of the work being implemented, highlights a range of important factors, outlines how evaluation is progressing and concludes by recommending further empirical research.
Resolution of the Vlasov-Maxwell system by PIC discontinuous Galerkin method on GPU with OpenCL
Directory of Open Access Journals (Sweden)
Crestetto Anaïs
2013-01-01
Full Text Available We present an implementation of a Vlasov-Maxwell solver for multicore processors. The Vlasov equation describes the evolution of charged particles in an electromagnetic field, solution of the Maxwell equations. The Vlasov equation is solved by a Particle-In-Cell method (PIC, while the Maxwell system is computed by a Discontinuous Galerkin method. We use the OpenCL framework, which allows our code to run on multicore processors or recent Graphic Processing Units (GPU. We present several numerical applications to two-dimensional test cases.
AdS/CFT superconductors with Power Maxwell electrodynamics: Reminiscent of the Meissner effect
Energy Technology Data Exchange (ETDEWEB)
Roychowdhury, Dibakar, E-mail: dibakar@bose.res.in [S.N. Bose National Centre for Basic Sciences, JD Block, Sector III, Salt Lake, Kolkata-700098 (India)
2013-01-08
Based on an analytic scheme and neglecting the back reaction effect several crucial properties of holographic s-wave superconductors have been investigated in the presence of an external magnetic field in the background of a D-dimensional Schwarzschild AdS space-time. Inspired by low energy limit of heterotic string theory, in the present Letter we replace the conventional Maxwell action by a Power Maxwell action. Immersing the holographic superconductors in an external static magnetic field the spatially dependent condensate solutions have been obtained analytically. Interestingly enough it is observed that condensation can form only below a certain critical field strength (B{sub c}). Finally, and most importantly it is observed that the value of this critical field strength increases as the mass of the scalar particles gets higher, which indicates the onset of a harder condensation.
Ampère–Maxwell law for a conducting wire: a topological perspective
International Nuclear Information System (INIS)
Ferreira, J M; Anacleto, Joaquim
2013-01-01
The integral form of Ampère–Maxwell's law for an arbitrarily-shaped wire is recast from a topological perspective, eliminating the need to use conduction current and displacement current terms to determine the magnetic field circulation around an arbitrarily-shaped loop. A generalized flux of the electric field is defined, enabling Ampère–Maxwell's law for magnetic field circulation to be written in a form which parallels that in the absence of conduction current. It is hoped that this work has educational interest since it provides an example of how topology can simplify the formulation of physical laws. The ideas presented herein are primarily intended for undergraduate students of electromagnetism, but may also be of interest to graduate students and teachers. (paper)
Energy Technology Data Exchange (ETDEWEB)
Nungesser, Ernesto; Rendall, Alan D [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, 14476 Potsdam (Germany)
2009-05-21
A proof of strong cosmic censorship is presented for a class of solutions of the Einstein-Maxwell equations, those with polarized Gowdy symmetry. A key element of the argument is the observation that by means of a suitable choice of variables the central equations in this problem can be written in a form where they are identical to the central equations for general (i.e. non-polarized) vacuum Gowdy spacetimes. Using this, it is seen that the deep results of Ringstroem on strong cosmic censorship in the vacuum case have implications for the Einstein-Maxwell case. Working out the geometrical meaning of these analytical results leads to the main conclusion.
Variational symmetries and conservation laws of the coupled Maxwell-Dirac equations
Fliss, Jackson; Menon, Balraj
2012-03-01
The role of symmetry groups has become increasing important in the study of modern physics. The theorems of Emmy Noether link conservation laws to symmetries of the action functional. Contact symmetries can be constructed from the invariance of the action under infinitesimal transformations that are dependent on the independent variables and the dependent variables. First-order generalized symmetries can be constructed by including the first derivatives of the dependent variables. In the case of the coupled Maxwell-Dirac equations, the independent variables and dependent variables are, respectively, the spacetime coordinates and the fields. In this talk I will review the familiar symmetries of field theory, as well as investigate the first-order generalized symmetries of the coupled Maxwell-Dirac equations. The local conservation laws associated with each of these, via the theorems of Noether, will be addressed as well.
Doubly stratified mixed convection flow of Maxwell nanofluid with heat generation/absorption
Energy Technology Data Exchange (ETDEWEB)
Abbasi, F.M., E-mail: abbasisarkar@gmail.com [Department of Mathematics, Comsats Institute of Information Technology, Islamabad 44000 (Pakistan); Shehzad, S.A. [Department of Mathematics, Comsats Institute of Information Technology, Sahiwal 57000 (Pakistan); Hayat, T. [Department of Mathematics, Quaid-i-Azam University, 45320, Islamabad 44000 (Pakistan); NAAM Research Group, Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Ahmad, B. [NAAM Research Group, Department of Mathematics, Faculty of Science, King Abdulaziz University, Jeddah 21589 (Saudi Arabia)
2016-04-15
Magnetohydrodynamic (MHD) doubly stratified flow of Maxwell nanofluid in presence of mixed convection is analyzed in this article. Effects of thermophoresis, Brownian motion and heat generation/absorption are present. The flow is induced due to linear stretching of sheet. Mathematical formulation is made under boundary layer approach. Expressions of velocity, temperature and nanoparticles concentration are developed. The obtained results are plotted and discussed to examine the variations in temperature and nanoparticles concentration due to different physical parameters. Numerical computations are made to obtain the values of local Nusselt and Sherwood numbers. Impact of sundry parameters on the flow quantities is analyzed graphically. - Highlights: • Double stratified flow of Maxwell nanofluid with mixed convection is modeled. • Thermophoresis and Brownian motion effects are encountered. • Computations are made to obtain the solution expressions. • Numerical values of local Nusselt and Sherwood numbers are computed and examined.
Parallel implementation of a relativistic semi-Lagrangian Vlasov-Maxwell solver
Sarrat, Mathieu; Ghizzo, Alain; Del Sarto, Daniele; Serrat, Laurent
2017-11-01
We describe the parallel implementation of a semi-Lagrangian relativistic VLasov ElectroMagnetic (VLEM) code for the numerical investigation of the dynamics of charged particle distribution in their self-consistent electromagnetic fields. This paper introduces the numerical solution of the Vlasov-Maxwell system in two spatial dimensions, and two or three momentum dimensions. Accuracy, stability, efficiency properties and the implementation of a new algorithm of charge conservation when solving Maxwell equations are discussed. The performances of the code are tested by studying the evolution of Weibel-type instabilities in the relativistic regime. Application to the coupling between Current Filamentation (CFI) and Two-Stream (TSI) instabilities is presented showing the importance of pair-wise vortex merging scenario in the saturation mechanism.
A new type of massive spin-one boson: And its relation with Maxwell equations
International Nuclear Information System (INIS)
Ahluwalia, D.V.
1995-01-01
First, the author showed that in the (1, 0) circle-plus (0, 1) representation space there exist not one but two theories for charged particles. In the Weinberg construct, the boson and its antiboson carry same relative intrinsic parity, whereas in the author's construct the relative intrinsic parities of the boson and its antiboson are opposite. These results originate from the commutativity of the operations of Charge conjugation and Parity in Weinberg's theory, and from the anti-commutativity of the operations of Charge conjugation and Parity in the author's theory. The author thus claims that he has constructed a first non-trivial quantum theory of fields for the Wigner-type particles. Second, the massless limit of both theories seems formally identical and suggests a fundamental modification of Maxwell equations. At its simplest level, the modification to Maxwell equations enters via additional boundary condition(s)
A geometric formulation of Einstein-Maxwell theory in Einstein-Cartan space-time
International Nuclear Information System (INIS)
Fonseca Neto, J.B. da; Rivelles, V.O.
1986-01-01
A geometry theory is proposed for electromagnetism and gravitation in which the electromagnetics potential is introduced in the geometry through the torsion. An action is first built for dyon electrodynamics using the two-potential formulation in such a way that it is equivalent to Maxwell theory if the ratio between electric and magnetic charges is a universal constant. Since the torsion can be decomposed into a trace, a pseudo-trace and a traceless part, the two potentials of the dyon electrodynamics with the two tracers of the torsion are identified and an action which reproduces the Einstein-Maxwell theory is built. Matter fields do not have a proper minimal coupling to this theory. (Author) [pt
Maxwell's fish-eye lens and the mirage of perfect imaging
International Nuclear Information System (INIS)
Merlin, R
2011-01-01
Recent claims that Maxwell's fish-eye is a perfect lens, capable of providing images with deep subwavelength resolution, are examined. We show that the imaging properties of a dispersionless fish-eye are very similar to those of an ideal spherical cavity. Using this correspondence, we prove that the correct solution to Maxwell equations in the fish-eye gives image sizes that are consistent with the standard diffraction limit. Perfect focusing is an optical illusion that results from placing a time-reversed source at the position of the geometrical image which, when combined with the field due to the primary (object) source, mimics the behavior of a perfect drain. Issues of causality are briefly discussed. We also demonstrate that passive outlets are not a good alternative to time-reversed sources for broadband drain-like behavior and that, even if they were, they could not do a better job than conventional optical systems at providing high resolution
Energy Technology Data Exchange (ETDEWEB)
Zhao, Guangpu [School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China); Jian, Yongjun, E-mail: jianyj@imu.edu.cn [School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China); Chang, Long [School of Mathematics and Statistics, Inner Mongolia University of Finance and Economics, Hohhot, Inner Mongolia 010051 (China); Buren, Mandula [School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China)
2015-08-01
By using the method of separation of variables, an analytical solution for the magnetohydrodynamic (MHD) flow of the generalized Maxwell fluids under AC electric field through a two-dimensional rectangular micropump is reduced. By the numerical computation, the variations of velocity profiles with the electrical oscillating Reynolds number Re, the Hartmann number Ha, the dimensionless relaxation time De are studied graphically. Further, the comparison with available experimental data and relevant researches is presented. - Highlights: • MHD flow of the generalized Maxwell fluids under AC electric field is analyzed. • The MHD flow is confined to a two-dimensional rectangular micropump. • Analytical solution is obtained by using the method of separation of variables. • The influences of related parameters on the MHD velocity are discussed.
International Nuclear Information System (INIS)
Zhao, Guangpu; Jian, Yongjun; Chang, Long; Buren, Mandula
2015-01-01
By using the method of separation of variables, an analytical solution for the magnetohydrodynamic (MHD) flow of the generalized Maxwell fluids under AC electric field through a two-dimensional rectangular micropump is reduced. By the numerical computation, the variations of velocity profiles with the electrical oscillating Reynolds number Re, the Hartmann number Ha, the dimensionless relaxation time De are studied graphically. Further, the comparison with available experimental data and relevant researches is presented. - Highlights: • MHD flow of the generalized Maxwell fluids under AC electric field is analyzed. • The MHD flow is confined to a two-dimensional rectangular micropump. • Analytical solution is obtained by using the method of separation of variables. • The influences of related parameters on the MHD velocity are discussed
Superconvergence of mixed finite element approximations to 3-D Maxwell's equations in metamaterials
Huang, Yunqing
2011-09-01
Numerical simulation of metamaterials has attracted more and more attention since 2000, after the first metamaterial with negative refraction index was successfully constructed. In this paper we construct a fully-discrete leap-frog type finite element scheme to solve the three-dimensional time-dependent Maxwell\\'s equations when metamaterials are involved. First, we obtain some superclose results between the interpolations of the analytical solutions and finite element solutions obtained using arbitrary orders of Raviart-Thomas-Nédélec mixed spaces on regular cubic meshes. Then we prove the superconvergence result in the discrete l2 norm achieved for the lowest-order Raviart-Thomas-Nédélec space. To our best knowledge, such superconvergence results have never been obtained elsewhere. Finally, we implement the leap-frog scheme and present numerical results justifying our theoretical analysis. © 2011 Elsevier Inc.
One-Dimensional Vlasov-Maxwell Equilibrium for the Force-Free Harris Sheet
International Nuclear Information System (INIS)
Harrison, Michael G.; Neukirch, Thomas
2009-01-01
In this Letter, the first nonlinear force-free Vlasov-Maxwell equilibrium is presented. One component of the equilibrium magnetic field has the same spatial structure as the Harris sheet, but whereas the Harris sheet is kept in force balance by pressure gradients, in the force-free solution presented here force balance is maintained by magnetic shear. Magnetic pressure, plasma pressure and plasma density are constant. The method used to find the equilibrium is based on the analogy of the one-dimensional Vlasov-Maxwell equilibrium problem to the motion of a pseudoparticle in a two-dimensional conservative potential. The force-free solution can be generalized to a complete family of equilibria that describe the transition between the purely pressure-balanced Harris sheet to the force-free Harris sheet
Double-black-hole solutions of the Einstein-Maxwell-dilaton theory in five dimensions
Stelea, Cristian
2018-01-01
We describe a solution-generating technique that maps a static charged solution of the Einstein-Maxwell theory in four (or five) dimensions to a five-dimensional solution of the Einstein-Maxwell-Dilaton theory. As examples of this technique first we show how to construct the dilatonic version of the Reissner-Nordström solution in five dimensions and then we consider the more general case of the double black hole solutions and describe some of their properties. We found that in the general case the value of the conical singularities in between the black holes is affected by the dilaton's coupling constant to the gauge field and only in the particular case when all charges are proportional to the masses this dependence cancels out.
Kirsch, Andreas
2015-01-01
This book gives a concise introduction to the basic techniques needed for the theoretical analysis of the Maxwell Equations, and filters in an elegant way the essential parts, e.g., concerning the various function spaces needed to rigorously investigate the boundary integral equations and variational equations. The book arose from lectures taught by the authors over many years and can be helpful in designing graduate courses for mathematically orientated students on electromagnetic wave propagation problems. The students should have some knowledge on vector analysis (curves, surfaces, divergence theorem) and functional analysis (normed spaces, Hilbert spaces, linear and bounded operators, dual space). Written in an accessible manner, topics are first approached with simpler scale Helmholtz Equations before turning to Maxwell Equations. There are examples and exercises throughout the book. It will be useful for graduate students and researchers in applied mathematics and engineers working in the theoretical ap...
Lifting particle coordinate changes of magnetic moment type to Vlasov-Maxwell Hamiltonian dynamics
International Nuclear Information System (INIS)
Morrison, P. J.; Vittot, M.; Guillebon, L. de
2013-01-01
Techniques for coordinate changes that depend on both dependent and independent variables are developed and applied to the Maxwell-Vlasov Hamiltonian theory. Particle coordinate changes with a new velocity variable dependent on the magnetic field, with spatial coordinates unchanged, are lifted to the field theoretic level, by transforming the noncanonical Poisson bracket and Hamiltonian structure of the Vlasov-Maxwell dynamics. Several examples are given including magnetic coordinates, where the velocity is decomposed into components parallel and perpendicular to the local magnetic field, and the case of spherical velocity coordinates. An example of the lifting procedure is performed to obtain a simplified version of gyrokinetics, where the magnetic moment is used as a coordinate and the dynamics is reduced by elimination of the electric field energy in the Hamiltonian.
Maxwell: A semi-analytic 4D code for earthquake cycle modeling of transform fault systems
Sandwell, David; Smith-Konter, Bridget
2018-05-01
We have developed a semi-analytic approach (and computational code) for rapidly calculating 3D time-dependent deformation and stress caused by screw dislocations imbedded within an elastic layer overlying a Maxwell viscoelastic half-space. The maxwell model is developed in the Fourier domain to exploit the computational advantages of the convolution theorem, hence substantially reducing the computational burden associated with an arbitrarily complex distribution of force couples necessary for fault modeling. The new aspect of this development is the ability to model lateral variations in shear modulus. Ten benchmark examples are provided for testing and verification of the algorithms and code. One final example simulates interseismic deformation along the San Andreas Fault System where lateral variations in shear modulus are included to simulate lateral variations in lithospheric structure.
International Nuclear Information System (INIS)
Davidson, Ronald C.; Lee, W. Wei-li; Hong Qin; Startsev, Edward
2001-01-01
This paper develops a clear procedure for solving the nonlinear Vlasov-Maxwell equations for a one-component intense charged particle beam or finite-length charge bunch propagating through a cylindrical conducting pipe (radius r = r(subscript)w = const.), and confined by an applied focusing force. In particular, the nonlinear Vlasov-Maxwell equations are Lorentz-transformed to the beam frame ('primed' variables) moving with axial velocity relative to the laboratory. In the beam frame, the particle motions are nonrelativistic for the applications of practical interest, already a major simplification. Then, in the beam frame, we make the electrostatic approximation which fully incorporates beam space-charge effects, but neglects any fast electromagnetic processes with transverse polarization (e.g., light waves). The resulting Vlasov-Maxwell equations are then Lorentz-transformed back to the laboratory frame, and properties of the self-generated fields and resulting nonlinear Vlasov-Maxwell equations in the laboratory frame are discussed
Maxwell Equation Violation by Density Dependent Magnetic Fields in Neutron Stars
Alloy, Marcelo D.; Menezes, Débora P.
We show that the widely used density dependent magnetic field prescriptions, necessary to account for the variation of the field intensity from the crust to the core of neutron stars violate one of the Maxwell equations. We estimate how strong the violation is when different equations of state are used and check for which cases the pathological problem can be cured. We then propose a simple solution that allows for the usual prescriptions to be used without violating a fundamental equation of physics.
Modular hp-FEM system HERMES and its application to Maxwell´s equations
Czech Academy of Sciences Publication Activity Database
Vejchodský, Tomáš; Šolín, P.; Zítka, M.
2007-01-01
Roč. 76, č. 2 (2007), s. 223-228 ISSN 0378-4754. [MODELLING 2005. Plzeň, 04.06.2005-08.06.2005] R&D Projects: GA ČR GP201/04/P021 Institutional research plan: CEZ:AV0Z10190503 Keywords : hp-FEM * time-harmonic Maxwell´s equations * hierarchic higher-order edge elements Subject RIV: BA - General Mathematics Impact factor: 0.738, year: 2007
T-S criticality of black holes with power Maxwell invariant source
Lin, Ze-Tao; Li, Gu-Qiang; Long, Kun; He, Fang; Mo, Jie-Xiong
2017-09-01
In this paper, we show that black holes with PMI source exhibit the T-S criticality and derive the relevant critical physical quantities analytically. The values of critical quantities for the case s≠1 vary from those for the case s=1, showing the effect of PMI field on the critical phenomena of black holes. When qPMI field does not affect the Maxwell equal area law.
Su, Benyu; Yu, Jingcun; Sheng, Chenxing; Zhang, Yulei
2017-01-01
Water-bearing geological structure is a serious threat to coalmine safety. This research focuses on detecting water-bearing geological structure by transient electromagnetic method. First, we introduce the principle of mining transient electromagnetic method, and then explain the technique of Finite Different Time Domain using in the transient electromagnetic method. Based on Maxwell equations, we derive the difference equations of electromagnetic field and study the responses of water-bearin...
An analogy between macroscopic and microscopic systems for Maxwell's equations in higher dimensions
Emre Kansu, Mustafa
2013-12-01
In this study, Maxwell's equations are discussed for macroscopic and microscopic systems by obtaining them from free and bound charge and current densities. In addition to electric and magnetic fields, the polarization and magnetization vectors are defined by the hyperbolic octonion basis. Finally, by introducing the hyperbolic octonionic field equation, for the first time, the hyperbolic octonionic source equation is represented in a simple, useful and elegant manner in terms of free charge, free and bound current densities.
Dynamical Mass Generation and Confinement in Maxwell-Chern-Simons Planar Quantum Electrodynamics
International Nuclear Information System (INIS)
Sanchez Madrigal, S; Raya, A; Hofmann, C P
2011-01-01
We study the non-perturbative phenomena of Dynamical Mass Generation and Confinement by truncating at the non-perturbative level the Schwinger-Dyson equations in Maxwell-Chern-Simons planar quantum electrodynamics. We obtain numerical solutions for the fermion propagator in Landau gauge within the so-called rainbow approximation. A comparison with the ordinary theory without the Chern-Simons term is presented.
A Short History of The Air University, Maxwell AFB, and the 42nd Air Base Wing
2014-07-31
bombers in 1956. Operated out of Ramey AFB, Puerto Rico (bombers), and Goose AB, Labrador (tankers), while runway repairs were made at Loring, 10 Jul–5...November 2011. In 2006-2007, AU’s structure and program effectiveness underwent an in-depth review that led to major changes in AU’s structure. In... hurricane Katrina devastated New Orleans, Maxwell-Gunter served as an evacuation center for over 1,000 displaced evacuees from the Gulf coast and as a
Infinitely many large energy solutions of superlinear Schrodinger-Maxwell equations
Directory of Open Access Journals (Sweden)
Lin Li
2012-12-01
Full Text Available In this article we study the existence of infinitely many large energy solutions for the superlinear Schrodinger-Maxwell equations $$displaylines{ -Delta u+V(xu+ phi u=f(x,u quad hbox{in }mathbb{R}^3,cr -Delta phi=u^2, quad hbox{in }mathbb{R}^3, }$$ via the Fountain Theorem in critical point theory. In particular, we do not use the classical Ambrosetti-Rabinowitz condition.
Boundary effects in 2 + 1 dimensional Maxwell-Chern-Simons theory
International Nuclear Information System (INIS)
Ferrer, E.J.; Incera, V. de la.
1996-09-01
The boundary effects in the screening of an applied magnetic field in a finite temperature 2 + 1 dimensional model of charged fermions minimally coupled to Maxwell and Chern-Simons fields are investigated. It is found that in a sample with only one boundary -a half-plane- a total Meissner effect takes place, while in a sample with two boundaries -an infinite strip- the external magnetic field partially penetrates the material. (author). 17 refs
Yvonnet, Julien; Liu, Liping
2017-01-01
International audience; In the present work, a numerical finite element framework is introduced to model and solve the response of nonlinear soft dielectrics, including the effects of Maxwell stress and flexoelectricity at finite strains. Weak forms, finite element discretizations and constistent linearizations, able to handle strain gradient in the context of flexo-electricity are introduced. Numerical algorithms for the treatment of a soft dielectric in a surrounding medium are presented, m...
Conformal Maxwell Theory as a Singleton Field Theory on $ADS_{5}$, IIB Three Branes and Duality
Ferrara, Sergio
1998-01-01
We examine the boundary conditions associated with extended supersymmetric Maxwell theory in 5-dimensional anti-De Sitter space. Excitations on the boundary are identical to those of ordinary 4-dimensional conformal invariant super electrodynammics. Extrapolations of these excitations give rise to a 5-dimensional topological gauge theory of the singleton type. The possibility of a connection of this phenomenon to the world volume theory of 3-branes in IIB string theory is discussed.
Classical Duality from Compactification of Self Dual 5-form Maxwell Theory in 10 dimensions
Berman, D S
1997-01-01
Duality of abelian gauge theories are considered. By compactifying a self dual p-form theory on some compact space, we determine the duality generator of the gauge theory. In this picture duality is seen as a consequence of the geometry of the compact space. We describe the compactification of 10-dimensional self dual 4-form Maxwell theory to give a theory in 4-dimensions with scalar, one form and two form fields that all transform non trivially under duality.
Uniqueness theorem for static phantom wormholes in Einstein-Maxwell-dilaton theory
Lazov, Boian; Nedkova, Petya; Yazadjiev, Stoytcho
2018-03-01
We prove a uniqueness theorem for completely regular traversable electrically charged wormhole solutions in the Einstein-Maxwell-dilaton gravity with a phantom scalar field and a possible phantom electromagnetic field. In a certain region of the parameter space, determined by the asymptotic values of the scalar field and the lapse function, the regular wormholes are completely specified by their mass, scalar charge and electric charge. The argument is based on the positive energy theorem applied on an appropriate conformally transformed Riemannian space.
Effective Hamiltonians, two level systems, and generalized Maxwell-Bloch equations
International Nuclear Information System (INIS)
Sczaniecki, L.
1981-02-01
A new method is proposed involving a canonical transformation leading to the non-secular part of time-independent perturbation calculus. The method is used to derive expressions for effective Shen-Walls Hamiltonians which, taken in the two-level approximation and on the inclusion of non-Hamiltonian terms into the dynamics of the system, lead to generalized Maxwell-Bloch equations. The rotating wave approximation is written anew within the framework of our formalism. (author)
Simultaneous exact controllability for Maxwell equations and for a second-order hyperbolic system
Directory of Open Access Journals (Sweden)
Boris V. Kapitonov
2010-02-01
Full Text Available We present a result on "simultaneous" exact controllability for two models that describe two hyperbolic dynamics. One is the system of Maxwell equations and the other a vector-wave equation with a pressure term. We obtain the main result using modified multipliers in order to generate a necessary observability estimate which allow us to use the Hilbert Uniqueness Method (HUM introduced by Lions.
Scattering amplitudes in N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity
Chiodaroli, Marco; Johansson, Henrik; Roiban, Radu
2015-01-01
We expose a double-copy structure in the scattering amplitudes of the generic Jordan family of N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity theories in four and five dimensions. The Maxwell-Einstein supergravity amplitudes are obtained through the color/kinematics duality as a product of two gauge-theory factors; one originating from pure N=2 super-Yang-Mills theory and the other from the dimensional reduction of a bosonic higher-dimensional pure Yang-Mills theory. We identify a specific symplectic frame in four dimensions for which the on-shell fields and amplitudes from the double-copy construction can be identified with the ones obtained from the supergravity Lagrangian and Feynman-rule computations. The Yang-Mills/Einstein supergravity theories are obtained by gauging a compact subgroup of the isometry group of their Maxwell-Einstein counterparts. For the generic Jordan family this process is identified with the introduction of cubic scalar couplings on the bosonic gauge-theory side, which th...
A comparison of Fick and Maxwell-Stefan diffusion formulations in PEMFC gas diffusion layers
Lindstrom, Michael; Wetton, Brian
2017-01-01
This paper explores the mathematical formulations of Fick and Maxwell-Stefan diffusion in the context of polymer electrolyte membrane fuel cell cathode gas diffusion layers. The simple Fick law with a diagonal diffusion matrix is an approximation of Maxwell-Stefan. Formulations of diffusion combined with mass-averaged Darcy flow are considered for three component gases. For this application, the formulations can be compared computationally in a simple, one dimensional setting. Despite the models' seemingly different structure, it is observed that the predictions of the formulations are very similar on the cathode when air is used as oxidant. The two formulations give quite different results when the Nitrogen in the air oxidant is replaced by helium (this is often done as a diagnostic for fuel cells designs). The two formulations also give quite different results for the anode with a dilute Hydrogen stream. These results give direction to when Maxwell-Stefan diffusion, which is more complicated to implement computationally in many codes, should be used in fuel cell simulations.
Alamri, Sagr; Li, Bing; Tan, K. T.
2018-03-01
Dissipative elastic metamaterials have attracted increased attention in recent times. This paper presents the development of a dissipative elastic metamaterial with multiple Maxwell-type resonators for stress wave attenuation. The mechanism of the dissipation effect on the vibration characteristics is systematically investigated by mass-spring-damper models with single and dual resonators. Based on the parameter optimization, it is revealed that a broadband wave attenuation region (stopping band) can be obtained by properly utilizing interactions from resonant motions and viscoelastic effects of the Maxwell-type oscillators. The relevant numerical verifications are conducted for various cases, and excellent agreement between the numerical and theoretical frequency response functions is shown. The design of this dissipative metamaterial system is further applied for dynamic load mitigation and blast wave attenuation. Moreover, the transient response in the continuum model is designed and analyzed for more robust design. By virtue of the bandgap merging effect induced by the Maxwell-type damper, the transient blast wave can be almost completely suppressed in the low frequency range. A significantly improved performance of the proposed dissipative metamaterials for stress wave mitigation is verified in both time and frequency domains.
Reformulation of Maxwell's equations to incorporate near-solute solvent structure.
Yang, Pei-Kun; Lim, Carmay
2008-09-04
Maxwell's equations, which treat electromagnetic interactions between macroscopic charged objects in materials, have explained many phenomena and contributed to many applications in our lives. Derived in 1861 when no methods were available to determine the atomic structure of macromolecules, Maxwell's equations assume the solvent to be a structureless continuum. However, near-solute solvent molecules are highly structured, unlike far-solute bulk solvent molecules. Current methods cannot treat both the near-solute solvent structure and time-dependent electromagnetic interactions in a macroscopic system. Here, we derive "microscopic" electrodynamics equations that can treat macroscopic time-dependent electromagnetic field problems like Maxwell's equations and reproduce the solvent molecular and dipole density distributions observed in molecular dynamics simulations. These equations greatly reduce computational expense by not having to include explicit solvent molecules, yet they treat the solvent electrostatic and van der Waals effects more accurately than continuum models. They provide a foundation to study electromagnetic interactions between molecules in a macroscopic system that are ubiquitous in biology, bioelectromagnetism, and nanotechnology. The general strategy presented herein to incorporate the near-solute solvent structure would enable studies on how complex cellular protein-ligand interactions are affected by electromagnetic radiation, which could help to prevent harmful electromagnetic spectra or find potential therapeutic applications.
Numerical Simulations of Self-Focused Pulses Using the Nonlinear Maxwell Equations
Goorjian, Peter M.; Silberberg, Yaron; Kwak, Dochan (Technical Monitor)
1994-01-01
This paper will present results in computational nonlinear optics. An algorithm will be described that solves the full vector nonlinear Maxwell's equations exactly without the approximations that are currently made. Present methods solve a reduced scalar wave equation, namely the nonlinear Schrodinger equation, and neglect the optical carrier. Also, results will be shown of calculations of 2-D electromagnetic nonlinear waves computed by directly integrating in time the nonlinear vector Maxwell's equations. The results will include simulations of 'light bullet' like pulses. Here diffraction and dispersion will be counteracted by nonlinear effects. The time integration efficiently implements linear and nonlinear convolutions for the electric polarization, and can take into account such quantum effects as Kerr and Raman interactions. The present approach is robust and should permit modeling 2-D and 3-D optical soliton propagation, scattering, and switching directly from the full-vector Maxwell's equations. Abstract of a proposed paper for presentation at the meeting NONLINEAR OPTICS: Materials, Fundamentals, and Applications, Hyatt Regency Waikaloa, Waikaloa, Hawaii, July 24-29, 1994, Cosponsored by IEEE/Lasers and Electro-Optics Society and Optical Society of America
L2-stability of the Vlasov-Maxwell-Boltzmann system near global Maxwellians
International Nuclear Information System (INIS)
Ha, Seung-Yeal; Xiao, Qinghua; Xiong, Linjie; Zhao, Huijiang
2013-01-01
We present a L 2 -stability theory of the Vlasov-Maxwell-Boltzmann system for the two-species collisional plasma. We show that in a perturbative regime of a global Maxwellian, the L 2 -distance between two strong solutions can be controlled by that between initial data in a Lipschitz manner. Our stability result extends earlier results [Ha, S.-Y. and Xiao, Q.-H., “A revisiting to the L 2 -stability theory of the Boltzmann equation near global Maxwellians,” (submitted) and Ha, S.-Y., Yang, X.-F., and Yun, S.-B., “L 2 stability theory of the Boltzmann equation near a global Maxwellian,” Arch. Ration. Mech. Anal. 197, 657–688 (2010)] on the L 2 -stability of the Boltzmann equation to the Boltzmann equation coupled with self-consistent external forces. As a direct application of our stability result, we show that classical solutions in Duan et al. [“Optimal large-time behavior of the Vlasov-Maxwell-Boltzmann system in the whole space,” Commun. Pure Appl. Math. 24, 1497–1546 (2011)] and Guo [“The Vlasov-Maxwell-Boltzmann system near Maxwellians,” Invent. Math. 153(3), 593–630 (2003)] satisfy a uniform L 2 -stability estimate. This is the first result on the L 2 -stability of the Boltzmann equation coupled with self-consistent field equations in three dimensions
Higher-derivative gravity with non-minimally coupled Maxwell field
Energy Technology Data Exchange (ETDEWEB)
Feng, Xing-Hui; Lue, H. [Beijing Normal University, Department of Physics, Center for Advanced Quantum Studies, Beijing (China)
2016-04-15
We construct higher-derivative gravities with a non-minimally coupled Maxwell field. The Lagrangian consists of polynomial invariants built from the Riemann tensor and the Maxwell field strength in such a way that the equations of motion are second order for both the metric and the Maxwell potential. We also generalize the construction to involve a generic non-minimally coupled p-form field strength. We then focus on one low-lying example in four dimensions and construct the exact magnetically charged black holes. We also construct exact electrically charged z = 2 Lifshitz black holes. We obtain approximate dyonic black holes for the small coupling constant or small charges. We find that the thermodynamics based on the Wald formalism disagrees with that derived from the Euclidean action procedure, suggesting this may be a general situation in higher-derivative gravities with non-minimally coupled form fields. As an application in the AdS/CFT correspondence, we study the entropy/viscosity ratio for the AdS or Lifshitz planar black holes, and find that the exact ratio can be obtained without having to know the details of the solutions, even for this higher-derivative theory. (orig.)
Ice bridges and ridges in the Maxwell-EB sea ice rheology
Dansereau, Véronique; Weiss, Jérôme; Saramito, Pierre; Lattes, Philippe; Coche, Edmond
2017-09-01
This paper presents a first implementation of a new rheological model for sea ice on geophysical scales. This continuum model, called Maxwell elasto-brittle (Maxwell-EB), is based on a Maxwell constitutive law, a progressive damage mechanism that is coupled to both the elastic modulus and apparent viscosity of the ice cover and a Mohr-Coulomb damage criterion that allows for pure (uniaxial and biaxial) tensile strength. The model is tested on the basis of its capability to reproduce the complex mechanical and dynamical behaviour of sea ice drifting through a narrow passage. Idealized as well as realistic simulations of the flow of ice through Nares Strait are presented. These demonstrate that the model reproduces the formation of stable ice bridges as well as the stoppage of the flow, a phenomenon occurring within numerous channels of the Arctic. In agreement with observations, the model captures the propagation of damage along narrow arch-like kinematic features, the discontinuities in the velocity field across these features dividing the ice cover into floes, the strong spatial localization of the thickest, ridged ice, the presence of landfast ice in bays and fjords and the opening of polynyas downstream of the strait. The model represents various dynamical behaviours linked to an overall weakening of the ice cover and to the shorter lifespan of ice bridges, with implications in terms of increased ice export through narrow outflow pathways of the Arctic.
Hybrid resonance and long-time asymptotic of the solution to Maxwell's equations
Energy Technology Data Exchange (ETDEWEB)
Després, Bruno, E-mail: despres@ann.jussieu.fr [Laboratory Jacques Louis Lions, University Pierre et Marie Curie, Paris VI, Boîte courrier 187, 75252 Paris Cedex 05 (France); Weder, Ricardo, E-mail: weder@unam.mx [Departamento de Física Matemática, Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas, Universidad Nacional Autónoma de México, Apartado Postal 20-126, DF 01000 (Mexico)
2016-03-22
We study the long-time asymptotic of the solutions to Maxwell's equation in the case of an upper-hybrid resonance in the cold plasma model. We base our analysis in the transfer to the time domain of the recent results of B. Després, L.M. Imbert-Gérard and R. Weder (2014) [15], where the singular solutions to Maxwell's equations in the frequency domain were constructed by means of a limiting absorption principle and a formula for the heating of the plasma in the limit of vanishing collision frequency was obtained. Currently there is considerable interest in these problems, in particular, because upper-hybrid resonances are a possible scenario for the heating of plasmas, and since they can be a model for the diagnostics involving wave scattering in plasmas. - Highlights: • The upper-hybrid resonance in the cold plasma model is considered. • The long-time asymptotic of the solutions to Maxwell's equations is studied. • A method based in a singular limiting absorption principle is proposed.
Electron-electron attractive interaction in Maxwell-Chern-Simons QED{sub 3} at zero temperature
Energy Technology Data Exchange (ETDEWEB)
Belich, H.; Ferreira Junior, M.M.; Helayel-Neto, J.A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). E-mail: belich@cbpf.br; manojr@cbpf.br; helayel@gft.ucp.br; Ferreira Junior, M.M. [Universidade Catolica de Petropolis, RJ (Brazil). Grupo de Fisica Teorica. E-mail: delcima@gft.ucp.br
2001-04-01
One discusses the issue of low-energy electron-electron bound states in the Maxwell-Chern-Simons model coupled to QED{sub 3} with spontaneous breaking of a local U(1)-symmetry. The scattering potential, in the non-relativistic limit, steaming from the electron-electron Moeller scattering, mediated by the Maxwell-Chern-Simons-Proca gauge field and the Higgs scalar, might be attractive by fine-tuning properly the physical parameters of the model. (author)
2008-10-01
Kevin . 2008. Personal communications via interview regarding firing range operations. February 15, 2008. Weston. 2005. Questions for Maxwell...of Oklahoma P.O. Drawer 1210 Durant , Oklahoma 74702 RE: Proposed Construction of New Training Facilities Maxwell Air Force Base, Alabama Dear Mr...FFICE w w w.prese rv ea la .org Choctaw Nation of Oklahoma P.O. Box 1210 • Durant , OK 74702-1210 • (580) 924-8280 April 14, 2008 Janet Lanier
Staff Definitions of Challenging Behavior.
Elgie, Sarah; Hastings, Richard P.
2002-01-01
Fifty staff working with adults with mental retardation rated potentially challenging behaviors in terms of: (1) whether they thought the behaviors were challenging, and (2) whether the behaviors should be the focus of intervention. Results found that staff were less likely to identify as challenging those behaviors having negative effects on…
2011 Elections to Staff Council
Staff Association
2011-01-01
Vote Elections to fill all seats in the Staff Council are being organized this month. Voting will begin on Monday 31 October. Make your voice heard and be many to elect the new Staff Council. By doing so, you will be encouraging the men and women who will represent you over the next two years and they will doubtless appreciate your gratitude. More details on the elections can be found on the Staff Association web site. (http://association.web.cern.ch) Elections Timetable Monday 31 October, at noon start date for voting Monday 14 November, at noon closing date for voting Monday 21 November, publication of the results in Echo Tuesday 22 and Wednesday 29 November Staff Association Assizes Tuesday 6 December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure is monitored by the Election Committee.
2010-07-01
... 32 National Defense 2 2010-07-01 2010-07-01 false Staff. 270.5 Section 270.5 National Defense... Staff. (a) The Commission will have a support staff, which will include staff members sufficient to expeditiously and efficiently process the applications for payments under this part. All members of the staff...
L’aide individualisée dans un collège RAR : présentation et analyse critique
Directory of Open Access Journals (Sweden)
Alain Marchive
2011-01-01
Full Text Available L’aide individualisée est au principe des principaux dispositifs mis en place par les collèges appartenant aux Réseaux Ambition Réussite (RAR créés en 2006, en vue d’atteindre les objectifs d’amélioration des performances scolaires assignés à ces « zones d’excellence pédagogique ». Après avoir présenté le cadre général qui a présidé à la mise en œuvre des RAR et les conceptions pédagogiques qui les sous-tendent, l’auteur s’appuie sur l’observation des actions d’aide dans un collège RAR et des entretiens menés auprès des professeurs d’une classe de 6e, des professeurs référents RAR et des assistants pédagogiques, pour décrire et analyser les actions d’aide mises en œuvre. Les principales questions soulevées concernent la compatibilité entre le traitement individualisé des difficultés scolaires et la logique didactique de l’enseignement collectif dans la classe, l’évaluation des actions d’aide et leur fonction effective, le caractère ambigu de ces dispositifs. Elles reviennent à poser la question centrale à laquelle est confronté tout professeur, à savoir celle de la gestion de l’hétérogénéité.Personalized help lies at the core of the main plans of action set up by secondary schools which are members of Réseaux Ambition Réussite (RAR networks. These networks were created in 2006 with the aim to improve the academic performances of pupils schooled in these areas of teaching excellence. Following a presentation of the general framework and of the teaching conceptions that presided over the implementation of RAR networks, the author describes and analyzes the various actions set up in a secondary school belonging to a RAR network. To back up his work, he uses interviews carried out with teachers of a class of 6ème, with RAR referring teachers, and with teaching assistants. The main questions that are raised concern the compatibility between the personalized treatment of
Rational-Emotive Staff Development.
Forman, Susan G.; Forman, Bruce D.
1980-01-01
The application of Rational-Emotive Therapy principles and techniques in in-service education for school personnel is discussed. Teacher and counselor participation in a staff development program is described. (Author)
SENIOR STAFF ADVANCEMENT COMMITTEE (SSAC)
2000-01-01
Composition and mandateThe Senior Staff Advancement Committee is composed of members nominated ad persona by the Director-General.The Committee examines proposals from Divisions concerning promotions to grade 13 in Career Path IX, changes of career path to Career Path IX and advancements to the exceptional grade in Career path VIII.The Director-General may consult the Committee on any matter related to senior staff careers.The Committee makes its recommendations to the Director-General.
Why join the Staff Association
Association du personnel
2011-01-01
Becoming a member of the Staff Association (SA) is above all a personal choice, showing that the joining person’s commitment and adherence to values such as solidarity, social cohesion, etc.In September, the SA launches a membership campaign to convince a maximum number to join, to inform, arouse interest and support. Posters, emails and individual contacts are part of the campaign programme, just like this editorial. As far as individual contacts are concerned, we ask you to give time and lend an ear to the delegates of your department in the Staff Council, who will approach you, in order to make an open and constructive discussion possible. Do not hesitate to ask questions and let them know your thoughts about the SA, as (constructive) criticism enables us to progress. The Staff Association and its role of collective representation The Staff Association, via its delegates, represents collectively all staff of the Organization before the Director-General and Member States. To do this, staff rep...
Staff Knowledge, Adherence to Infection Control Recommendations ...
African Journals Online (AJOL)
Staff Knowledge, Adherence to Infection Control Recommendations and Seroconversion Rates in Hemodialysis Centers in Khartoum. ... Adherence of staff members to infection control recommendations was evaluated by direct observation. Results: ... A structured training program for HD staff members is urgently required.
Self-consistent Maxwell-Bloch theory of quantum-dot-population switching in photonic crystals
International Nuclear Information System (INIS)
Takeda, Hiroyuki; John, Sajeev
2011-01-01
We theoretically demonstrate the population switching of quantum dots (QD's), modeled as two-level atoms in idealized one-dimensional (1D) and two-dimensional (2D) photonic crystals (PC's) by self-consistent solution of the Maxwell-Bloch equations. In our semiclassical theory, energy states of the electron are quantized, and electron dynamics is described by the atomic Bloch equation, while electromagnetic waves satisfy the classical Maxwell equations. Near a waveguide cutoff in a photonic band gap, the local electromagnetic density of states (LDOS) and spontaneous emission rates exhibit abrupt changes with frequency, enabling large QD population inversion driven by both continuous and pulsed optical fields. We recapture and generalize this ultrafast population switching using the Maxwell-Bloch equations. Radiative emission from the QD is obtained directly from the surrounding PC geometry using finite-difference time-domain simulation of the electromagnetic field. The atomic Bloch equations provide a source term for the electromagnetic field. The total electromagnetic field, consisting of the external input and radiated field, drives the polarization components of the atomic Bloch vector. We also include a microscopic model for phonon dephasing of the atomic polarization and nonradiative decay caused by damped phonons. Our self-consistent theory captures stimulated emission and coherent feedback effects of the atomic Mollow sidebands, neglected in earlier treatments. This leads to remarkable high-contrast QD-population switching with relatively modest (factor of 10) jump discontinuities in the electromagnetic LDOS. Switching is demonstrated in three separate models of QD's placed (i) in the vicinity of a band edge of a 1D PC, (ii) near a cutoff frequency in a bimodal waveguide channel of a 2D PC, and (iii) in the vicinity of a localized defect mode side coupled to a single-mode waveguide channel in a 2D PC.
Maxwell Strata and Cut Locus in the Sub-Riemannian Problem on the Engel Group
Ardentov, Andrei A.; Sachkov, Yuri L.
2017-12-01
We consider the nilpotent left-invariant sub-Riemannian structure on the Engel group. This structure gives a fundamental local approximation of a generic rank 2 sub-Riemannian structure on a 4-manifold near a generic point (in particular, of the kinematic models of a car with a trailer). On the other hand, this is the simplest sub-Riemannian structure of step three. We describe the global structure of the cut locus (the set of points where geodesics lose their global optimality), the Maxwell set (the set of points that admit more than one minimizer), and the intersection of the cut locus with the caustic (the set of conjugate points along all geodesics). The group of symmetries of the cut locus is described: it is generated by a one-parameter group of dilations R+ and a discrete group of reflections Z2 × Z2 × Z2. The cut locus admits a stratification with 6 three-dimensional strata, 12 two-dimensional strata, and 2 one-dimensional strata. Three-dimensional strata of the cut locus are Maxwell strata of multiplicity 2 (for each point there are 2 minimizers). Two-dimensional strata of the cut locus consist of conjugate points. Finally, one-dimensional strata are Maxwell strata of infinite multiplicity, they consist of conjugate points as well. Projections of sub-Riemannian geodesics to the 2-dimensional plane of the distribution are Euler elasticae. For each point of the cut locus, we describe the Euler elasticae corresponding to minimizers coming to this point. Finally, we describe the structure of the optimal synthesis, i. e., the set of minimizers for each terminal point in the Engel group.
DC and Hall conductivity in holographic massive Einstein-Maxwell-Dilaton gravity
Energy Technology Data Exchange (ETDEWEB)
Zhou, Zhenhua [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China); Wu, Jian-Pin [Institute of Gravitation and Cosmology, Department of Physics,School of Mathematics and Physics,Bohai University, Jinzhou 121013 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics,Chinese Academy of Sciences, Beijing 100190 (China); Ling, Yi [Institute of High Energy Physics, Chinese Academy of Sciences,Beijing 100049 (China); State Key Laboratory of Theoretical Physics, Institute of Theoretical Physics,Chinese Academy of Sciences, Beijing 100190 (China)
2015-08-14
We investigate the holographic DC and Hall conductivity in massive Einstein-Maxwell-Dilaton (EMD) gravity. Two special EMD backgrounds are considered explicitly. One is dyonic Reissner-Nordström-AdS (RN-AdS) geometry and the other one is hyperscaling violation AdS (HV-AdS) geometry. We find that the linear-T resistivity and quadratic-T inverse Hall angle can be simultaneously achieved in HV-AdS models, providing a hint to construct holographic models confronting with the experimental data of strange metal in future.
Theory of the Maxwell pressure tensor and the tension in a water bridge.
Widom, A; Swain, J; Silverberg, J; Sivasubramanian, S; Srivastava, Y N
2009-07-01
A water bridge refers to an experimental "flexible cable" made up of pure de-ionized water, which can hang across two supports maintained with a sufficiently large voltage difference. The resulting electric fields within the de-ionized water flexible cable maintain a tension that sustains the water against the downward force of gravity. A detailed calculation of the water bridge tension will be provided in terms of the Maxwell pressure tensor in a dielectric fluid medium. General properties of the dielectric liquid pressure tensor are discussed along with unusual features of dielectric fluid Bernoulli flows in an electric field. The "frictionless" Bernoulli flow is closely analogous to that of a superfluid.
(2 + 1)-dimensional dynamical black holes in Einstein-nonlinear Maxwell theory
Gurtug, O.; Mazharimousavi, S. Habib; Halilsoy, M.
2018-02-01
Radiative extensions of BTZ metric in 2 + 1 dimensions are found which are sourced by nonlinear Maxwell fields and a null current. This may be considered as generalization of the problem formulated long go by Vaidya and Bonnor. The mass and charge are functions of retarded/advanced null coordinate apt for decay/inflation. The new solutions are constructed through a Theorem that works remarkably well for any nonlinear electrodynamic model. Hawking temperature is analyzed for the case of the Born-Infeld electrodynamics.
Partial Fourier analysis of time-harmonic Maxwell's equations in axisymmetric domains
International Nuclear Information System (INIS)
Nkemzi, Boniface
2003-01-01
We analyze the Fourier method for treating time-harmonic Maxwell's equations in three-dimensional axisymmetric domains with non-axisymmetric data. The Fourier method reduces the three-dimensional boundary value problem to a system of decoupled two-dimensional boundary value problems on the plane meridian domain of the axisymmetric domain. The reduction process is fully described and suitable weighted spaces are introduced on the meridian domain to characterize the two-dimensional solutions. In particular, existence and uniqueness of solutions of the two-dimensional problems is proved and a priori estimates for the solutions are given. (author)
On Some Unusual Properties of Wave Solutions of Free Maxwell Equations
Augusto Espinoza; Andrey Chubykalo
2006-01-01
Se descubren algunas propiedades inusuales de las soluciones de las llamadas ecuaciones libres de Maxwell. Mostramos la existencia de soluciones que representan las ondas electromagnéticas en el vacío para los cuales el vector de Poynting no coincide con el vector de Umov. Se presentan soluciones que corresponden a ondas magnéticas estacionarias de una configuración inusual en el vacío, que describen en el vacio formaciones estables anulares y esféricas de campo. Se demuestra que en el vacío,...
A negative-norm least-squares method for time-harmonic Maxwell equations
Copeland, Dylan M.
2012-04-01
This paper presents and analyzes a negative-norm least-squares finite element discretization method for the dimension-reduced time-harmonic Maxwell equations in the case of axial symmetry. The reduced equations are expressed in cylindrical coordinates, and the analysis consequently involves weighted Sobolev spaces based on the degenerate radial weighting. The main theoretical results established in this work include existence and uniqueness of the continuous and discrete formulations and error estimates for simple finite element functions. Numerical experiments confirm the error estimates and efficiency of the method for piecewise constant coefficients. © 2011 Elsevier Inc.
International Nuclear Information System (INIS)
Budinich, Paolo
2009-03-01
In a previous paper we proposed a purely mathematical way to quantum mechanics based on Cartan's simple spinors in their most elementary form of 2 components spinors. Here we proceed along that path proposing, this time, a symmetric tensor, quadrilinear in simple spinors, as a candidate for the symmetric tensor of general relativity. The procedure resembles closely that in which one builds bilinearly from simple spinors an asymmetric electromagnetic tensor, from which easily descend Maxwell's equations and the photon can be seen as a bilinear combination of neutrinos. Here Lorentzian spaces result compact, building up spheres, where hopefully the problems of the Standard Model could be solved. (author)
Liu, Meilin
2012-08-01
A discontinuous Galerkin finite element method (DG-FEM) with a highly accurate time integration scheme for solving Maxwell equations is presented. The new time integration scheme is in the form of traditional predictor-corrector algorithms, PE CE m, but it uses coefficients that are obtained using a numerical scheme with fully controllable accuracy. Numerical results demonstrate that the proposed DG-FEM uses larger time steps than DG-FEM with classical PE CE) m schemes when high accuracy, which could be obtained using high-order spatial discretization, is required. © 1963-2012 IEEE.
High-order accurate methods for solving the time-harmonic Maxwell's equations
Wilcox, Lucas Charles
Maxwell's equations are the partial differential equations describing electromagnetism. They can be used to model electric and magnetic fields in different materials from light in fiber optic cables to radar waves bouncing off a stealth fighter jet. In problems with electromagnetic radiation of a single frequency Maxwell's equations may be reduced to their time-harmonic form. Further simplifying the problem a multilayer boundary variation method for the forward modeling of multilayered diffraction optics is presented. This approach enables fast and high-order accurate modeling of periodic transmission optics consisting of an arbitrary number of materials and interfaces of general shape subject to plane wave illumination or, by solving a sequence of problems, illumination by beams. The key developments of the algorithm are discussed as are details of an efficient implementation. Numerous comparisons with exact solutions and highly accurate direct solutions confirm the accuracy, versatility, and efficiency of the proposed method. The high accuracy of the method is leveraged to solve an application involving the in-coupling process for grating-coupled planar optical waveguide sensors. For more general solutions of the time-harmonic Maxwell's equations an hp-adaptive discontinuous Galerkin finite element method is studied. The discontinuous Galerkin finite element method is a general method for solving partial differential equations that has had success with time evolution problems. The application to time-harmonic problems is a new and developing area of research. As a first step, an overlapping Schwarz method for the discontinuous Galerkin discretization of the indefinite Helmholtz equation is examined. For an hp-adaptive method to be successful an error indicator is required to determine the areas of the computational domain that need increased resolution. The use of adjoint based error indicators is explored through solving the time-harmonic Maxwell's equations for
Total Energy of Charged Black Holes in Einstein-Maxwell-Dilaton-Axion Theory
Directory of Open Access Journals (Sweden)
Murat Korunur
2012-01-01
Full Text Available We focus on the energy content (including matter and fields of the Møller energy-momentum complex in the framework of Einstein-Maxwell-Dilaton-Axion (EMDA theory using teleparallel gravity. We perform the required calculations for some specific charged black hole models, and we find that total energy distributions associated with asymptotically flat black holes are proportional to the gravitational mass. On the other hand, we see that the energy of the asymptotically nonflat black holes diverge in a limiting case.
Sakiadis flow of Maxwell fluid considering magnetic field and convective boundary conditions
Energy Technology Data Exchange (ETDEWEB)
Mustafa, M., E-mail: meraj-mm@hotmail.com [School of Natural Sciences (SNS), National University of Sciences and Technology (NUST), Islamabad 44000 (Pakistan); Khan, Junaid Ahmad [Research Centre for Modeling and Simulation (RCMS), National University of Sciences and Technology (NUST), Islamabad 44000 (Pakistan); Hayat, T. [Department of Mathematics, Quaid-I-Azam University 45320, Islamabad 44000 (Pakistan); Nonlinear Analysis and Applied Mathematics (NAAM) Research Group, King Abdulaziz University, P. O. Box 80257, Jeddah 21589 (Saudi Arabia); Alsaedi, A. [Nonlinear Analysis and Applied Mathematics (NAAM) Research Group, King Abdulaziz University, P. O. Box 80257, Jeddah 21589 (Saudi Arabia)
2015-02-15
In this paper we address the flow of Maxwell fluid due to constantly moving flat radiative surface with convective condition. The flow is under the influence of non-uniform transverse magnetic field. The velocity and temperature distributions have been evaluated numerically by shooting approach. The solution depends on various interesting parameters including local Deborah number De, magnetic field parameter M, Prandtl number Pr and Biot number Bi. We found that variation in velocity with an increase in local Deborah number De is non-monotonic. However temperature is a decreasing function of local Deborah number De.
The Maxwell-Einstein system, Ward identities and the Vilkovisky construction
DEFF Research Database (Denmark)
Nielsen, N. K.
2012-01-01
The gauge fixing dependence of the one-loop effective action of quantum gravity in the proper-time representation is investigated for a space of arbitrary curvature, and the investigation is extended to Maxwell-Einstein theory. The construction of Vilkovisky and DeWitt for removal......-Abelian gauge theories; they are used to address the question of gauge dependence of asymptotic freedom arising through internal graviton lines at one-loop order as suggested by Robinson and Wilczek. (C) 2011 Elsevier Inc. All rights reserved....
Rincón, Ángel; Panotopoulos, Grigoris
2018-01-01
We study for the first time the stability against scalar perturbations, and we compute the spectrum of quasinormal modes of three-dimensional charged black holes in Einstein-power-Maxwell nonlinear electrodynamics assuming running couplings. Adopting the sixth order Wentzel-Kramers-Brillouin (WKB) approximation we investigate how the running of the couplings change the spectrum of the classical theory. Our results show that all modes corresponding to nonvanishing angular momentum are unstable both in the classical theory and with the running of the couplings, while the fundamental mode can be stable or unstable depending on the running parameter and the electric charge.
The free-electron laser - Maxwell's equations driven by single-particle currents
Colson, W. B.; Ride, S. K.
1980-01-01
It is shown that if single particle currents are coupled to Maxwell's equations, the resulting set of self-consistent nonlinear equations describes the evolution of the electron beam and the amplitude and phase of the free-electron-laser field. The formulation is based on the slowly varying amplitude and phase approximation, and the distinction between microscopic and macroscopic scales, which distinguishes the microscopic bunching from the macroscopic pulse propagation. The capabilities of this new theoretical approach become apparent when its predictions for the ultrashort pulse free-electron laser are compared to experimental data; the optical pulse evolution, determined simply and accurately, agrees well with observations.
Uniqueness theorem for static phantom wormholes in Einstein–Maxwell-dilaton theory
Directory of Open Access Journals (Sweden)
Boian Lazov
2018-03-01
Full Text Available We prove a uniqueness theorem for completely regular traversable electrically charged wormhole solutions in the Einstein–Maxwell-dilaton gravity with a phantom scalar field and a possible phantom electromagnetic field. In a certain region of the parameter space, determined by the asymptotic values of the scalar field and the lapse function, the regular wormholes are completely specified by their mass, scalar charge and electric charge. The argument is based on the positive energy theorem applied on an appropriate conformally transformed Riemannian space.
Chen, Qiang; Qin, Hong; Liu, Jian; Xiao, Jianyuan; Zhang, Ruili; He, Yang; Wang, Yulei
2017-11-01
An infinite dimensional canonical symplectic structure and structure-preserving geometric algorithms are developed for the photon-matter interactions described by the Schrödinger-Maxwell equations. The algorithms preserve the symplectic structure of the system and the unitary nature of the wavefunctions, and bound the energy error of the simulation for all time-steps. This new numerical capability enables us to carry out first-principle based simulation study of important photon-matter interactions, such as the high harmonic generation and stabilization of ionization, with long-term accuracy and fidelity.
Fast semi-analytical solution of Maxwell's equations in Born approximation for periodic structures.
Pisarenco, Maxim; Quintanilha, Richard; van Kraaij, Mark G M M; Coene, Wim M J
2016-04-01
We propose a fast semi-analytical approach for solving Maxwell's equations in Born approximation based on the Fourier modal method (FMM). We show that, as a result of Born approximation, most matrices in the FMM algorithm become diagonal, thus allowing a reduction of computational complexity from cubic to linear. Moreover, due to the analytical representation of the solution in the vertical direction, the number of degrees of freedom in this direction is independent of the wavelength. The method is derived for planar illumination with two basic polarizations (TE/TM) and an arbitrary 2D geometry infinitely periodic in one horizontal direction.
Directory of Open Access Journals (Sweden)
SAVULESCU Adrian
2014-11-01
Full Text Available This paper attempts to present the necessary steps in designing a electrical generator represented in 2D, 3D, finite element analysis software of Ansoft Maxwell magnetic fields. This work includes modeling form of generator, boundaries, excitations, parameterization, the analysis of the mesh, optimization, performance and representation fields: A (Flux Vector Lines and A, H (Mag_H and H Vector, B (Mag_B and B vector J (Jz and J vector and the energy and other analyzes as CoreLoss, Ohmic_Loss and Total_Loss.
Newton's 2nd Law, Radiation Reaction & Type II Einstein-Maxwell Fields
Newman, Ezra T.
2011-01-01
Considering perturbations off the Reissner-Nordstrom metric while keeping the perturbations in the class of type II Einstein-Maxwell metrics, we do a spherical harmonic expansion of all the variables up to the quadrupole term. This leads to a rather surprising results. Referring to the source of the metric as a type II particle (analogous to referring to a Schwarzschild-Reissner-Nordstrom or Kerr-Newman particle), we see immediately that the Bondi momentum of the particle take the classical f...
Self-consistent Maxwell-Bloch model of quantum-dot photonic-crystal-cavity lasers
DEFF Research Database (Denmark)
Cartar, William; Mørk, Jesper; Hughes, Stephen
2017-01-01
We present a powerful computational approach to simulate the threshold behavior of photonic-crystal quantum-dot (QD) lasers. Using a finite-difference time-domain (FDTD) technique, Maxwell-Bloch equations representing a system of thousands of statistically independent and randomly positioned two...... on both the passive cavity and active lasers, where the latter show a general increase in the pump threshold for cavity lengths greater than N = 7, and a reduction in the nominal cavity mode volume for increasing amounts of disorder....
On the motion of hairy black holes in Einstein-Maxwell-dilaton theories
Julié, Félix-Louis
2018-01-01
Starting from the static, spherically symmetric black hole solutions in massless Einstein-Maxwell-dilaton (EMD) theories, we build a "skeleton" action, that is, we phenomenologically replace black holes by an appropriate effective point particle action, which is well suited to the formal treatment of the many-body problem in EMD theories. We find that, depending crucially on the value of their scalar cosmological environment, black holes can undergo steep "scalarization" transitions, inducing large deviations to the general relativistic two-body dynamics, as shown, for example, when computing the first post-Keplerian Lagrangian of EMD theories.
Sirenko, Kostyantyn
2014-07-01
Discontinuous Galerkin time-domain method (DGTD) has been used extensively in computational electromagnetics for analyzing transient electromagnetic wave interactions on structures described with linear constitutive relations. DGTD expands unknown fields independently on disconnected mesh elements and uses numerical flux to realize information exchange between fields on different elements (J. S. Hesthaven and T. Warburton, Nodal Discontinuous Galerkin Method, 2008). The numerical flux of choice for \\'linear\\' Maxwell equations is the upwind flux, which mimics accurately the physical behavior of electromagnetic waves on discontinuous boundaries. It is obtained from the analytical solution of the Riemann problem defined on the boundary of two neighboring mesh elements.
Ge, Hao; Qian, Hong
2009-10-02
We show that the thermodynamic limit of a bistable phosphorylation-dephosphorylation cycle has a selection rule for the "more stable" macroscopic steady state. The analysis is akin to the Maxwell construction. Based on the chemical master equation approach, it is shown that, except at a critical point, bistability disappears in the stochastic model when fluctuation is sufficiently low but unneglectable. Onsager's Gaussian fluctuation theory applies to the unique macroscopic steady state. With an initial state in the basin of attraction of the "less stable" steady state, the deterministic dynamics obtained by the law of mass action is a metastable phenomenon. Stability and robustness in cell biology are emergent stochastic concepts.
The electric theories of J. Clerk Maxwell a historical and critical study
Duhem, Pierre Maurice Marie
2015-01-01
In this volume Pierre Duhem first gives an overview of 19th century electricity and magnetism. Next, he applies his keen historical, philosophical, and physical intuition to critiquing Maxwell's theories, especially his electromagnetic theory of light and the ad hoc introduction of displacement current, which he considers too much a product of the "esprit de géométrie" than the "esprit de finesse," as Pascal calls it. In this book, Duhem is guided by the principle that a theory that offers contradictions, even if the theory is posed by a genius, needs to be analysed and discussed until a c
Implications of staff 'churn' for nurse managers, staff, and patients.
Duffield, Christine; Roche, Michael; O'Brien-Pallas, Linda; Catling-Paull, Christine
2009-01-01
In this article, the term "churn" is used not only because of the degree of change to staffing, but also because some of the reasons for staff movement are not classified as voluntary turnover. The difficulties for the nurse managing a unit with the degree of "churn" should not be under-estimated. Changes to skill mix and the proportions of full-time, agency, and temporary staff present challenges in providing clinical leadership, scheduling staff, performance management, and supervision. Perhaps more importantly, it is likely that there is an impact on the continuity of care provided in the absence of continuity of staffing. A greater understanding of the human and financial costs and consequences, and a willingness to change established practices at the institutional and ward level, are needed.
Training of technical staff and technical staff managers
International Nuclear Information System (INIS)
Moody, G.F.
1991-01-01
The purpose of Technical Staff and Technical Staff Managers training is to provide job skills enhancement to individuals selected to fill key technical positions within a nuclear utility. This training is unique in that unlike other training programs accredited by the National Academy for Nuclear Training, it does not lead to specific task qualification. The problems encountered when determining the student population and curriculum are a direct result of this major difference. Major problems encountered are determining who should attend the training, what amount of training is necessary and sufficient, and how to obtain the best feedback in order to effect substantive program improvements. These topics will be explored and possible solutions discussed
Radiation monitoring of PET staff
International Nuclear Information System (INIS)
Trang, A.
2004-01-01
Full text: Positron emission tomography (PET) is becoming a common diagnostic tool in hospitals, often located in and employing staff from the Nuclear Medicine or Radiology departments. Although similar in some ways, staff in PET departments are commonly found to have the highest radiation doses in the hospital environment due to unique challenges which PET tracers present in administration as well as production. The establishment of a PET centre with a dedicated cyclotron has raised concerns of radiation protection to the staff at the WA PET Centre and the Radiopharmaceutical Production and Development (RAPID) team. Since every PET centre has differing designs and practices, it was considered important to closely monitor the radiation dose to our staff so that improvements to practices and design could be made to reduce radiation dose. Electronic dosimeters (MGP DMC 2000XB), which have a facility to log time and dose at 10 second intervals, were provided to three PET technologists and three PET nurses. These were worn in the top pocket of their lab coats throughout a whole day. Each staff member was then asked to note down their duties throughout the day and also note the time they performed each duty. The duties would then correlate with the dose with which the electronic monitor recorded and an estimate of radiation dose per duty could be given. Also an estimate of the dose per day to each staff member could be made. PET nurses averaged approximately 20 μ8v per day getting their largest dose from caring for occasional problematic patients. Smaller doses of a 1-2 μ8v were recorded for injections and removing cannulas. PET technologists averaged approximately 15 μ8v per day getting their largest dose of 1-5μ8v mainly from positioning of patients and sometimes larger doses due to problematic patients. Smaller doses of 1-2 μ5v were again recorded for injections and removal of cannulas. Following a presentation given to staff, all WA PET Centre and RAPID staff
NO to sacrificing future staff!
Staff Association
2011-01-01
During our public meetings last week, we reviewed several subjects. However, the most urgent one today is the 2nd package of measures for our Pension Fund. In our previous issue, we devoted a long article to the Management’s plan for staff recruited from January 2012. A disaster! As we announced at our meetings, the Staff Association will organize a referendum at the beginning of April. For the message to be heard it is vital that as many staff as possible take part. By voting you will express your support to your staff representatives to stand in the way of these unacceptable measures. It is a matter of urgency that the staff makes their voice heard. Time is short, the decisions will be made in June. The future of our Organization is as stake. This is our future colleagues we are talking about. We must prevent this sacrifice. They must be welcomed in such a manner that there is no uneasiness between us. They must be made to feel welcome in their new family, CERN, our CERN. That they should pay an ...
2017 Elections to Staff Council
Staff Association
2017-01-01
Make your voice heard, support your candidates! After verification by the Electoral Commission, all candidates for the elections to the Staff Council have been registered. It is now up to you, members of the Staff Association, to vote for the candidate(s) of your choice. We hope that you will be many to vote and to elect the new Staff Council! By doing so, you can support and encourage the women and men, who will represent you over the next two years. We are using an electronic voting system; all you need to do is click the link below and follow the instructions on the screen. https://ap-vote.web.cern.ch/elections-2017 The deadline for voting is Monday, 13 November at midday (12 pm). Elections Timetable Monday 13 November, at noon Closing date for voting Tuesday 21 November and Tuesday 5 December Publication of the results in Echo Monday 27 and Tuesday 28 November Staff Association Assizes Tuesday 5 December (afternoon) First meeting of the new Staff Council and election of the new Executive Committee The ...
Energy Technology Data Exchange (ETDEWEB)
Hayat, T. [Department of Mathematics, Quaid-i-Azam University 45320, Islamabad 44000 (Pakistan); Department of Mathematics, Faculty of Science, King Abdulaziz University, P. O. Box 80257, Jeddah 21589 (Saudi Arabia); Iqbal, Z., E-mail: zahidiqbal_qau@yahoo.com [Department of Mathematics, Quaid-i-Azam University 45320, Islamabad 44000 (Pakistan); Mustafa, M. [Research Centre for Modeling and Simulation, National University of Sciences and Technology, Sector H-12, Islamabad 44000 (Pakistan); Alsaedi, A. [Department of Mathematics, Faculty of Science, King Abdulaziz University, P. O. Box 80257, Jeddah 21589 (Saudi Arabia)
2012-11-15
Highlights: Black-Right-Pointing-Pointer Boundary layer flow of an upper-convected Maxwell (UCM) fluid over a moving surface. Black-Right-Pointing-Pointer Convective boundary conditions have been used. Black-Right-Pointing-Pointer Series solutions are obtained by homotopy analysis method (HAM). Black-Right-Pointing-Pointer Graphical results for various interesting parametric values. - Abstract: This study discusses the flow and heat transfer in an upper-convected Maxwell (UCM) fluid over a moving surface in the presence of a free stream velocity. The convective boundary conditions have been handled. Similarly transformations are invoked to convert the partial differential equations governing the steady flow of a Maxwell fluid into an ordinary differential system. This system is solved by a homotopic approach. The effects of influential parameters such as Deborah number ({beta}), Prandtl number (Pr), Eckert number (Ec), suction parameter (S) and ratio ({lambda}) have been thoroughly examined.
On the Generalized Maxwell Equations and Their Prediction of Electroscalar Wave
Directory of Open Access Journals (Sweden)
Arbab A. I.
2009-04-01
Full Text Available We have formulated the basic laws of electromagnetic theory in quaternion form. The formalism shows that Maxwell equations and Lorentz force are derivable from just one quaternion equation that only requires the Lorentz gauge. We proposed a quaternion form of the continuity equation from which we have derived the ordinary continuity equation. We introduce new transformations that produces a scalar wave and generalize the continuity equation to a set of three equations. These equations imply that both current and density are waves. Moreover, we have shown that the current can not cir- culate around a point emanating from it. Maxwell equations are invariant under these transformations. An electroscalar wave propagating with speed of light is derived upon requiring the invariance of the energy conservation equation under the new transforma- tions. The electroscalar wave function is found to be proportional to the electric field component along the charged particle motion. This scalar wave exists with or without considering the Lorentz gauge. We have shown that the electromagnetic fields travel with speed of light in the presence or absence of free charges.
Theoretical and numerical study of the equations of Vlasov-Maxwell in the covariant formalism
International Nuclear Information System (INIS)
Back, A.
2011-11-01
A new point of view is proposed for the simulation of plasmas using the kinetic model which links the equations of Vlasov for the distribution of particles and the equations of Maxwell for the electromagnetic contribution of fields. We use the following principle: the equations of Physics are mathematical objects which put in relation geometrical objects. To preserve the geometrical properties of the various objects in an equation, we use, for the theoretical and numerical study, the differential geometry. All the equations of Physics can be written with differential forms and this point of view is not dependent on the choice of coordinates. We propose then a discretization of the differential forms by using B-Splines. To be coherent with the theory, we also propose a discretization of the various operations of the differential geometry. We test our scheme, first on the equations of Maxwell with several boundary conditions and since it does not depend on the system of coordinates, we also test it when we change coordinates. Finally, we apply the same method to the equations of Vlasov-Poisson in one-dimension and we propose several numerical schemes. (author)
Radiating black holes in Einstein-Maxwell-dilaton theory and cosmic censorship violation
Energy Technology Data Exchange (ETDEWEB)
Aniceto, Pedro [CENTRA, Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa,Avenida Rovisco Pais 1, 1049 Lisboa (Portugal); Pani, Paolo [Dipartimento di Fisica, “Sapienza” Università di Roma & Sezione INFN Roma 1,Piazzale Aldo Moro 5, 00185 Roma (Italy); CENTRA, Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa,Avenida Rovisco Pais 1, 1049 Lisboa (Portugal); Rocha, Jorge V. [Departament de Física Fonamental, Institut de Ciències del Cosmos (ICCUB),Universitat de Barcelona,Martí i Franquès 1, E-08028 Barcelona (Spain)
2016-05-19
We construct exact, time-dependent, black hole solutions of Einstein-Maxwell-dilaton theory with arbitrary dilaton coupling, a. For a=1 this theory arises as the four-dimensional low-energy effective description of heterotic string theory. These solutions represent electrically charged, spherically symmetric black holes emitting or absorbing charged null fluids and generalize the Vaidya and Bonnor-Vaidya solutions of general relativity and of Einstein-Maxwell theory, respectively. The a=1 case stands out as special, in the sense that it is the only choice of the coupling that allows for a time-dependent dilaton field in this class of solutions. As a by-product, when a=1 we show that an electrically charged black hole in this theory can be overcharged by bombarding it with a stream of electrically charged null fluid, resulting in the formation of a naked singularity. This provides an example of cosmic censorship violation in an exact dynamical solution to low-energy effective string theory and in a case in which the total stress-energy tensor satisfies all energy conditions. When a≠1, our solutions necessarily have a time-independent scalar field and consequently cannot be overcharged.
Yu, Peicheng; Li, Fei; Dalichaouch, Thamine; Fiuza, Frederico; Decyk, Viktor; Davidson, Asher; Tableman, Adam; An, Weiming; Tsung, Frank; Fonseca, Ricardo; Lu, Wei; Vieira, Jorge; Silva, Luis; Mori, Warren
2016-10-01
we present a finite-difference-time-domain (FDTD) Maxwell solver for the particle-in-cell (PIC) algorithm, which is customized to effectively eliminate the numerical Cerenkov instability (NCI) which arises when a plasma (neutral or non-neutral) relativistically drifts on a grid when using the PIC algorithm. We control the EM dispersion curve in the direction of the plasma drift of a FDTD Maxwell solver by using a customized higher order finite difference operator for the spatial derivative along the direction of the drift (1& circ; direction). We show that this eliminates the main NCI modes with moderate | k1 | , while keeps additional main NCI modes well outside the range of physical interest with higher | k1 | . These main NCI modes can be easily filtered out along with first spatial aliasing NCI modes which are also at the edge of the fundamental Brillouin zone. The customized solver has the possible advantage of improved parallel scalability because it can be easily partitioned along 1& circ; which typically has many more cells than other directions for the problems of interest.
Fractional Generalizations of Maxwell and Kelvin-Voigt Models for Biopolymer Characterization.
Directory of Open Access Journals (Sweden)
Bertrand Jóźwiak
Full Text Available The paper proposes a fractional generalization of the Maxwell and Kelvin-Voigt rheological models for a description of dynamic behavior of biopolymer materials. It was found that the rheological models of Maxwell-type do not work in the case of modeling of viscoelastic solids, and the model which significantly better describes the nature of changes in rheological properties of such media is the modified fractional Kelvin-Voigt model with two built-in springpots (MFKVM2. The proposed model was used to describe the experimental data from the oscillatory and creep tests of 3% (w/v kuzu starch pastes, and to determine the values of their rheological parameters as a function of pasting time. These parameters provide a lot of additional information about structure and viscoelastic properties of the medium in comparison to the classical analysis of dynamic curves G' and G" and shear creep compliance J(t. It allowed for a comprehensive description of a wide range of properties of kuzu starch pastes, depending on the conditions of pasting process.
International Nuclear Information System (INIS)
Accioly, A.J.
1988-01-01
A theory of nonminimal coupling of electromagnetism and gravitation in the framework of Riomannian geometry is constructed. As a consequence the main difficulties concerning the Einstein-Maxwell theory are cleared away. The theory works as a kind of correction to the Einstein-Maxwell one for regions with strong curvature and for times much greater than the Planck time. A Reissner-Nordstroem-type solution is exhibited and comments are made on a parameter which somewhat resembles the ''Schwarzschild radius''. A mechanism of charge creation via nonminimal coupling is also discussed. We calculate the propagation of photons in a Robertson-Walker background and find that the effect of the nonminimal coupling in this case may be to deviate the photon from the null geodesics, increasing its velocity beyond the flat-space value. Taking into account this results, the observed isotropy of the background radiation can be explained in a simple way, regardless of any assumption about the state of the Universe prior to the Planck time. (author) [pt
Directory of Open Access Journals (Sweden)
Z. Shafique
Full Text Available Here we study the heat/mass transfer effects on revolving flow of Maxwell fluid due to unidirectional stretching surface. Mass transfer process is modeled in terms of binary chemical reaction and activation energy. Modified Arrhenius function for activation energy is invoked. Traditional boundary layer approximations are utilized to simplify the governing equations. Using similarity method, self-similar form of boundary layer equations are derived which are solved numerically. The solutions depend on dimensionless numbers such as the rotation parameter λ, the Deborah number β, the Prandtl number Pr, the Schmidt number Sc, activation energy E, fitted rate constant n and temperature difference parameter δ. We found that the solute concentration in binary mixture is proportional to both rotation parameter λ and activation energy E. The reaction rate σ and fitted rate n both provide reduction in the solute concentration. Thermal boundary layer becomes thicker and heat transfer rate diminishes when fluid is subjected to a larger rotation rate. Keywords: Maxwell fluid, Activation energy, Chemical reaction, Numerical solution, Rotating frame, Stretching sheet
Fractional Generalizations of Maxwell and Kelvin-Voigt Models for Biopolymer Characterization.
Jóźwiak, Bertrand; Orczykowska, Magdalena; Dziubiński, Marek
2015-01-01
The paper proposes a fractional generalization of the Maxwell and Kelvin-Voigt rheological models for a description of dynamic behavior of biopolymer materials. It was found that the rheological models of Maxwell-type do not work in the case of modeling of viscoelastic solids, and the model which significantly better describes the nature of changes in rheological properties of such media is the modified fractional Kelvin-Voigt model with two built-in springpots (MFKVM2). The proposed model was used to describe the experimental data from the oscillatory and creep tests of 3% (w/v) kuzu starch pastes, and to determine the values of their rheological parameters as a function of pasting time. These parameters provide a lot of additional information about structure and viscoelastic properties of the medium in comparison to the classical analysis of dynamic curves G' and G" and shear creep compliance J(t). It allowed for a comprehensive description of a wide range of properties of kuzu starch pastes, depending on the conditions of pasting process.
Radiating black holes in Einstein-Maxwell-dilaton theory and cosmic censorship violation
Aniceto, Pedro; Pani, Paolo; Rocha, Jorge V.
2016-05-01
We construct exact, time-dependent, black hole solutions of Einstein-Maxwell-dilaton theory with arbitrary dilaton coupling, a. For a = 1 this theory arises as the four-dimensional low-energy effective description of heterotic string theory. These solutions represent electrically charged, spherically symmetric black holes emitting or absorbing charged null fluids and generalize the Vaidya and Bonnor-Vaidya solutions of general relativity and of Einstein-Maxwell theory, respectively. The a = 1 case stands out as special, in the sense that it is the only choice of the coupling that allows for a time-dependent dilaton field in this class of solutions. As a by-product, when a = 1 we show that an electrically charged black hole in this theory can be overcharged by bombarding it with a stream of electrically charged null fluid, resulting in the formation of a naked singularity. This provides an example of cosmic censorship violation in an exact dynamical solution to low-energy effective string theory and in a case in which the total stress-energy tensor satisfies all energy conditions. When a ≠ 1, our solutions necessarily have a time-independent scalar field and consequently cannot be overcharged.
Ut Pictura Poesis : dialéctica entre palabras e imagen en Sir William Sterling Maxwell
Directory of Open Access Journals (Sweden)
Hilary Macartney
2002-01-01
Full Text Available En el presente artículo se analiza la estrecha relación entre la historia del arte de Sir William Stirling Maxwell, su biblioteca y su colección artística. Este vínculo encierra la clave para la comprensión de su excepcional aportación a la historiografía del arte español. Sus diversas actividades, como historiador del arte, coleccionista de libros y cuadros, y director de ediciones privadas de libros raros, fueron todas manifestaciones de su gran fascinación por el paralelo entre la literatura y el arte, la palabra y la imagen. Tal relación se encuentra incluso en el esquema decorativo de su biblioteca.This article examines the remarkable unity between Sir William Stirling Maxwell's art history, his library and his art collection and argües that this relationship is the key to understanding his unique contribution to scholarship of Spanish art. In particular, it will be shown that his actlvities as an art historian, bibliophile, art collector and editor of prívate editions of rare books were all expressions of his fascination with the relationship between literature and art in general, and more specifically between word and image. Even the decorative scheme of his library emphasised this relationship.
Comparisons of the Maxwell and CLL gas/surface interaction models using DSMC
Hedahl, Marc O.; Wilmoth, Richard G.
1995-12-01
The behavior of two different models of gas-surface interactions is studied using the Direct Simulation Monte Carlo (DSMC) method. The DSMC calculations examine differences in predictions of aerodynamic forces and heat transfer between the Maxwell and the Cercignani-Lampis-Lord (CLL) models for flat plate configurations at freestream conditions corresponding to a 140 km orbit around Venus. The size of the flat plate represents one of the solar panels on the Magellan spacecraft, and the freestream conditions correspond to those experienced during aerobraking maneuvers. Results are presented for both a single flat plate and a two-plate configuration as a function of angle of attack and gas-surface accommodation coefficients. The two-plate system is not representative of the Magellan geometry but is studied to explore possible experiments that might be used to differentiate between the two gas-surface interaction models. The Maxwell and CLL models produce qualitatively similar results for the aerodynamic forces and heat transfer on a single flat plate. However, the flow fields produced with the two models are qualitatively different for both the single-plate and two-plate calculations. These differences in the flowfield lead to predictions of the angle of attack for maximum heat transfer in a two plate configuration that are distinctly different for the two gas-surface interactions models.
Three-dimensional stationary cyclic symmetric Einstein-Maxwell solutions; black holes
International Nuclear Information System (INIS)
Garcia, Alberto A.
2009-01-01
From a general metric for stationary cyclic symmetric gravitational fields coupled to Maxwell electromagnetic fields within the (2 + 1)-dimensional gravity the uniqueness of wide families of exact solutions is established. Among them, all uniform electromagnetic solutions possessing electromagnetic fields with vanishing covariant derivatives, all fields having constant electromagnetic invariants F μν F μν and T μν T μν , the whole classes of hybrid electromagnetic solutions, and also wide classes of stationary solutions are derived for a third-order nonlinear key equation. Certain of these families can be thought of as black hole solutions. For the most general set of Einstein-Maxwell equations, reducible to three nonlinear equations for the three unknown functions, two new classes of solutions - having anti-de Sitter spinning metric limit - are derived. The relationship of various families with those reported by different authors' solutions has been established. Among the classes of solutions with cosmological constant a relevant place is occupied by the electrostatic and magnetostatic Peldan solutions, the stationary uniform and spinning Clement classes, the constant electromagnetic invariant branches with the particular Kamata-Koikawa solution, the hybrid cyclic symmetric stationary black hole fields, and the non-less important solutions generated via SL(2,R)-transformations where the Clement spinning charged solution, the Martinez-Teitelboim-Zanelli black hole solution, and Dias-Lemos metric merit mention.
Cao, Xia; Zhang, Meng; Huang, Jinrong; Jiang, Tao; Zou, Jingdian; Wang, Ning; Wang, Zhong Lin
2018-02-01
Wireless power delivery has been a dream technology for applications in medical science, security, radio frequency identification (RFID), and the internet of things, and is usually based on induction coils and/or antenna. Here, a new approach is demonstrated for wireless power delivery by using the Maxwell's displacement current generated by an electrodeless triboelectric nanogenerator (TENG) that directly harvests ambient mechanical energy. A rotary electrodeless TENG is fabricated using the contact and sliding mode with a segmented structure. Due to the leakage of electric field between the segments during relative rotation, the generated Maxwell's displacement current in free space is collected by metal collectors. At a gap distance of 3 cm, the output wireless current density and voltage can reach 7 µA cm -2 and 65 V, respectively. A larger rotary electrodeless TENG and flexible wearable electrodeless TENG are demonstrated to power light-emitting diodes (LEDs) through wireless energy delivery. This innovative discovery opens a new avenue for noncontact, wireless energy transmission for applications in portable and wearable electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Resolution of the Staff Council
Staff Association
2015-01-01
You were many to attend the public information meetings organised in October and we thank you for your interest. In this decision phase of the current Five-Yearly Review of our employment conditions they provided an opportunity to review the Management proposals in detail. They were a moment of exchange also on the various topics under review, and your comments were many and very valuable. Meeting on Thursday 29th October, the Staff Council discussed once more these proposals. It considered that the "package" of proposed measures is not balanced enough in its current form. It decided to formulate additional requests to the Management, relating mainly to the effects of the introduction of the proposed new career system. The resolution adopted this morning also implies that the consultation of staff, originally foreseen next week, is postponed. The staff Council will reconvene in a special session on Thursday, 5th November to reassess its position depending on the progress made regarding its d...
2017 Elections to Staff Council
Staff Association
2017-01-01
Make your voice heard, support your candidates! We hope that you will be many to vote and to elect the new Staff Council! By doing so, you can support and encourage the women and men, who will represent you over the next two years. The voting takes place from 23 October to 13 November, at noon at https://ap-vote.web.cern.ch/elections-2017. Elections Timetable Monday 13 November, at noon Closing date for voting Tuesday 21 November and Tuesday 5 December Publication of the results in Echo Monday 27 and Tuesday 28 November Staff Association Assizes Tuesday 5 December (afternoon) First meeting of the new Staff Council and election of the new Executive Committee The voting procedure will be monitored by the Election Committee, which is also in charge of announcing the results in Echo on 21 November and 5 December. Candidates for the 2017 Elections
Supported Conversation for hospital staff
DEFF Research Database (Denmark)
Forchhammer, Hysse B; Løvholt, Annelise P.; Mathiesen, Lone Lundbak
in communication and interaction, Supported Conversation for Adults with Aphasia (SCA) was adapted and implemented in a large neurological department at Rigshospitalet-Glostrup in Copenhagen. Method 152 staff members representing different health professionals were assigned to one of eleven courses during a six...... month period. Each course had 10-12 participants and lasted 6 hours, including instruction in the SCA principles, video analysis, interdisciplinary group work, and practice sessions with PWAs. Self-assessed learning outcomes were evaluated with a brief questionnaire filled out by staff members...... in communication, also showed significant improvements across all staff groups. After the course, more time to spend with patients was perceived as the most important factor to further increase communication success with PWA. Conclusion The results show that interdisciplinary SCA-courses successfully increase...
Staff Development for School Improvement: An Illustration.
Edelfelt, Roy A., Ed.
This document contains 11 papers on school staff development: (1) "The Staff Development for School Improvement Program" (Winifred I. Warnat); (2) "A Teacher's View of a Staff Development Project" (Lynn Kleiman); (3) "Staff Development from the Principal's Perspective" (Dixie Hibner); (4) "Stepping-Stones to Success" (Barbara A. Skone); (5)…
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Board staff. 902.3 Section 902.3 Foreign Relations FOREIGN SERVICE GRIEVANCE BOARD ORGANIZATION § 902.3 Board staff. The chairperson shall select the Board's executive secretary and other staff provided for in the Act. The executive secretary and staff...
17 CFR 8.05 - Enforcement staff.
2010-04-01
... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Enforcement staff. 8.05... staff. (a) Each exchange shall establish an adequate enforcement staff which shall be authorized by the... staff shall consist of employees of the exchange and/or persons hired on a contract basis. It may not...
Lan, Xiao-Gang
2013-05-01
By introducing a new tortoise coordinate transformation, we apply Damour-Ruffini-Sannan method to study the Hawking radiation of massive scalar particles in a dynamic Dilaton-Maxwell black hole. We find that Hawking radiation spectrum shows still the blackbody one, while the Hawking temperature is significantly changed. Additionally, by adopting the thin film method, we calculate the entropy of a dynamic Dilaton-Maxwell black hole. The result indicates that the entropy for such a black hole is still in proportional to the area of its event horizon.
If Maxwell had worked between Ampère and Faraday: An historical fable with a pedagogical moral
Jammer, Max; Stachel, John
1980-01-01
If one drops the Faraday induction term from Maxwell's equations, they become exactly Galilei invariant. This suggests that if Maxwell had worked between Ampère and Faraday, he could have developed this Galilei-invariant electromagnetic theory so that Faraday's discovery would have confronted physicists with the dilemma: give up the Galileian relativity principle for electromagnetism (ether hypothesis), or modify it (special relativity). This suggests a new pedagogical approach to electromagnetic theory, in which the displacement current and the Galileian relativity principle are introduced before the induction term is discussed.
Joseph, Rose M.; Hagness, Susan C.; Taflove, Allen
1991-01-01
The initial results for femtosecond pulse propagation and scattering interactions for a Lorentz medium obtained by a direct time integration of Maxwell's equations are reported. The computational approach provides reflection coefficients accurate to better than 6 parts in 10,000 over the frequency range of dc to 3 x 10 to the 16th Hz for a single 0.2-fs Gaussian pulse incident upon a Lorentz-medium half-space. New results for Sommerfeld and Brillouin precursors are shown and compared with previous analyses. The present approach is robust and permits 2D and 3D electromagnetic pulse propagation directly from the full-vector Maxwell's equations.
International Nuclear Information System (INIS)
2006-01-01
Ministry of Health of the Slovak Republic pursuant to par. 30 section 3 point b of the Act no. 124/2006 Coll. safety and health at work and amending certain laws provides the method of reporting occupational diseases and the threat of occupational disease. Occupational disease and risk of occupational disease notified in writing on a form which appears in the Annex, the Clinical Occupational Medicine and Clinical Toxicology, Department of Clinical occupational medicine and clinical toxicology or occupational medicine clinic and clinical toxicology in Bratislava, Martin or Kosice (as 'specialized work'), which is an occupational disease and risk of occupational disease admitted. This Regulation came into force on October 1, 2006.
Piqué Ruché, Javier
2016-01-01
Es realitzarà un assaig clínic, aleatori controlat i amb cec únic, donant començament al novembre de 2015 i finalitzant el juny de 2017. La mostra estarà formada per persones majors de 65 anys diagnosticades de fractura de Colles no articular, dividint la intervenció en 3 grups , tenint una durada de 3 mesos. Un primer grup rebrà com a intervenció l'escaiola de guix i tractament convencional; un segon grup la fèrula dissenyada mitjançant impressió tridimensional i tractament convencional, i u...
English for Airport Ground Staff
Cutting, Joan
2012-01-01
This article describes part of a European Commission Leonardo project that aimed to design a multimedia course for English language learners seeking work as ground staff in European airports. The structural-functional analysis of the dialogues written from the course showed that, across the four trades explored (security guards, ground handlers,…
Agency Directionality and Staff Individuality.
Hurst, James C.; And Others
Psychologists who choose work as members of counseling agencies are likely to experience some dissonance between what their individual interests and skills would have them do professionally and what they are asked to do as a staff member of the agency. Conversely, as a component of a larger institution or community, an agency's very existence may…
Creativity in nursing staff development.
Geyer, K A; Korte, P D
1990-01-01
The use of creative teaching techniques in nursing staff development generates enthusiasm for learning in both the learner and the educator. We report the process used to develop alternative teaching approaches and examples of these programs. A cost analysis of a traditional versus an innovative program is provided. Advantages and disadvantages of these approaches are reviewed.
2006-01-01
TÜ teadustöötajaist ja õppejõududest on 2/3 doktorikraadiga. TÜ rektor Jaak Aaviksoo ja teadusprprektor Ain Heinaru valiti Euroopa kõrghariduspoliitika juhtorganitesse. Sotsiaalteaduskonna prof. Wolfgang Drechsler sai Saksa-Eesti akadeemiliste suhete arendamise eest Saksamaa Liitvabariigi Teeneteristi
International Nuclear Information System (INIS)
Miao, Yan-Gang; Xu, Zhen-Ming
2017-01-01
We investigate the P - V criticality and the Maxwell equal area law for a five-dimensional spherically symmetric AdS black hole with a scalar hair in the absence of and in the presence of a Maxwell field, respectively. Especially in the charged case, we give the exact P - V critical values. More importantly, we analyze the validity and invalidity of the Maxwell equal area law for the AdS hairy black hole in the scenarios without and with charges, respectively. Within the scope of validity of the Maxwell equal area law, we point out that there exists a representative van der Waals-type oscillation in the P - V diagram. This oscillating part, which indicates the phase transition from a small black hole to a large one, can be replaced by an isobar. The small and large black holes have the same Gibbs free energy. We also give the distribution of the critical points in the parameter space both without and with charges, and we obtain for the uncharged case the fitting formula of the co-existence curve. Meanwhile, the latent heat is calculated, which gives the energy released or absorbed between the small and large black hole phases in the isothermal-isobaric procedure. (orig.)
2013-07-30
... organizations, has determined that a cultural item listed in this notice meets the definition of sacred object... organization not identified in this notice that wish to claim this cultural item should submit a written....R50000] Notice of Intent to Repatriate Cultural Item: Maxwell Museum of Anthropology, University of New...
The James clerk maxwell telescope legacy survey of nearby star-forming regions in the gould belt
Ward-Thompson, D.; Di Francesco, J.; Hatchell, J.; Hogerheijde, M. R.; Nutter, D.; Bastien, P.; Basu, S.; Bonnell, I.; Bowey, J.; Brunt, C.; Buckle, J.; Butner, H.; Cavanagh, B.; Chrysostomou, A.; Curtis, E.; Davis, C. J.; Dent, W. R. F.; van Dishoeck, E.; Edmunds, M. G.; Fich, M.; Fiege, J.; Fissel, L.; Friberg, P.; Friesen, R.; Frieswijk, W.; Fuller, G. A.; Gosling, A.; Graves, S.; Greaves, J. S.; Helmich, F.; Hills, R. E.; Holland, W. S.; Houde, M.; Jayawardhana, R.; Johnstone, D.; Joncas, G.; Kirk, H.; Kirk, J. M.; Knee, L. B. G.; Matthews, B.; Matthews, H.; Matzner, C.; Moriarty-Schieven, G. H.; Naylor, D.; Padman, R.; Plume, R.; Rawlings, J. M. C.; Redman, R. O.; Reid, M.; Richer, J. S.; Shipman, R.; Simpson, R. J.; Spaans, M.; Stamatellos, D.; Tsamis, Y. G.; Viti, S.; Weferling, B.; White, G. J.; Whitworth, A. P.; Wouterloot, J.; Yates, J.; Zhu, M.
This paper describes a James Clerk Maxwell Telescope (JCMT) legacy survey that has been awarded roughly 500 hr of observing time to be carried out from 2007 to 2009. In this survey, we will map with SCUBA-2 (Submillimetre Common-User Bolometer Array 2) almost all of the well-known low-mass and
Gravitational and electromagnetic potentials of the stationary Einstein-Maxwell field equations
International Nuclear Information System (INIS)
Jones, T.C.
1979-01-01
Associated with the stationary Einstein-Maxwell field equations is an infinite hierarchy of potentials. The basic characteristics of these potentials are examined in general and then in greater detail for the particular case of the Reissner-Nordstrom metric. Thier essential utility in the process of solution generation is elucidated, and the necessary equations for solution generation are developed. Appropriate generating functions, which contain the complete infinite hierarchy of potentials, are developed and analyzed. Particular attention is paid to the inherent gauge freedom of these generating functions. Two methods of solution generation, which yield asymptotically flat solutions in vacuum, are generalized to include electromagnetism. One method, using potentials consistent with the Harrison transformation and the Reissner-Nordstrom metric, is discussed in detail, and its resultant difficulties are explored
Impact of Maxwell rigidity transitions on resistance drift phenomena in GexTe1-x glasses
Luckas, J.; Olk, A.; Jost, P.; Volker, H.; Alvarez, J.; Jaffré, A.; Zalden, P.; Piarristeguy, A.; Pradel, A.; Longeaud, C.; Wuttig, M.
2014-09-01
Amorphous chalcogenides usually exhibit a resistivity, which increases with age following a power law ρ ˜ tα. Existing theories link this change in amorphous state resistivity to structural relaxation. Here, the impact of fundamental glass properties on resistance drift phenomena in amorphous GexTe1-x networks is studied. Employing Raman spectroscopy, the Maxwell rigidity transition from flexible to stressed rigid is determined to occur in the compositional range 0.250 0.265) exhibit rather strong resistance drift, where the drift parameters increase steadily from α = 0.13 for amorphous GeTe to α = 0.29 for compositions near the stiffness threshold xc. On the other hand, the drift parameter in flexible glasses (x decreases with decreasing Ge content x to values as low as α = 0.05. These findings illustrate the strong impact of the stiffness threshold on resistance drift phenomena in chalcogenides.
An elementary solution of the Maxwell equations for a time-dependent source
International Nuclear Information System (INIS)
Rivera, R; Villarroel, D
2002-01-01
We present an elementary solution of the Maxwell equations for a time-dependent source consisting of an infinite solenoid with a current density that increases linearly with time. The geometrical symmetries and the time dependence of the current density make possible a mathematical treatment that does not involve the usual technical difficulties, thus making this presentation suitable for students that are taking a first course in electromagnetism. We also show that the electric field generated by the solenoid can be used to construct an exact solution of the relativistic equation of motion of the electron that takes into account the effect of the radiation. In particular, we derive, in an almost trivial way, the formula for the radiation rate of an electron in circular motion
Decay estimates of solutions to the bipolar non-isentropic compressible Euler-Maxwell system
Tan, Zhong; Wang, Yong; Tong, Leilei
2017-10-01
We consider the global existence and large time behavior of solutions near a constant equilibrium state to the bipolar non-isentropic compressible Euler-Maxwell system in {R}3 , where the background magnetic field could be non-zero. The global existence is established under the assumption that the H 3 norm of the initial data is small, but its higher order derivatives could be large. Combining the negative Sobolev (or Besov) estimates with the interpolation estimates, we prove the optimal time decay rates of the solution and its higher order spatial derivatives. In this sense, our results improve the similar ones in Wang et al (2012 SIAM J. Math. Anal. 44 3429-57).
VizieR Online Data Catalog: Jame Clerk Maxwell Telescope Science Archive (CADC, 2003)
Canadian Astronomy Data, Centre
2018-01-01
The JCMT Science Archive (JSA), a collaboration between the CADC and EOA, is the official distribution site for observational data obtained with the James Clerk Maxwell Telescope (JCMT) on Mauna Kea, Hawaii. The JSA search interface is provided by the CADC Search tool, which provides generic access to the complete set of telescopic data archived at the CADC. Help on the use of this tool is provided via tooltips. For additional information on instrument capabilities and data reduction, please consult the SCUBA-2 and ACSIS instrument pages provided on the JAC maintained JCMT pages. JCMT-specific help related to the use of the CADC AdvancedSearch tool is available from the JAC. (1 data file).
Dimensional reduction of a Lorentz and CPT-violating Maxwell-Chern-Simons model
Energy Technology Data Exchange (ETDEWEB)
Belich, H. Jr.; Helayel Neto, J.A. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil). Coordenacao de Teoria de Campos e Particulas; Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil); E-mails: belich@cbpf.br; helayel@cbpf.br; Ferreira, M.M. Jr. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil); Maranhao Univ., Sao Luiz, MA (Brazil). Dept. de Fisica]. E-mail: manojr@cbpf.br; Orlando, M.T.D. [Grupo de Fisica Teorica Jose Leite Lopes, Petropolis, RJ (Brazil); Espirito Santo Univ., Vitoria, ES (Brazil). Dept. de Fisica e Quimica; E-mail: orlando@cce.ufes.br
2003-01-01
Taking as starting point a Lorentz and CPT non-invariant Chern-Simons-like model defined in 1+3 dimensions, we proceed realizing its dimensional to D = 1+2. One then obtains a new planar model, composed by the Maxwell-Chern-Simons (MCS) sector, a Klein-Gordon massless scalar field, and a coupling term that mixes the gauge field to the external vector, {nu}{sup {mu}}. In spite of breaking Lorentz invariance in the particle frame, this model may preserve the CPT symmetry for a single particular choice of {nu}{sup {mu}} . Analyzing the dispersion relations, one verifies that the reduced model exhibits stability, but the causality can be jeopardized by some modes. The unitary of the gauge sector is assured without any restriction , while the scalar sector is unitary only in the space-like case. (author)
Dimensional reduction of a Lorentz and CPT-violating Maxwell-Chern-Simons model
International Nuclear Information System (INIS)
Belich, H. Jr.; Helayel Neto, J.A.; Ferreira, M.M. Jr.; Maranhao Univ., Sao Luiz, MA; Orlando, M.T.D.; Espirito Santo Univ., Vitoria, ES
2003-01-01
Taking as starting point a Lorentz and CPT non-invariant Chern-Simons-like model defined in 1+3 dimensions, we proceed realizing its dimensional to D = 1+2. One then obtains a new planar model, composed by the Maxwell-Chern-Simons (MCS) sector, a Klein-Gordon massless scalar field, and a coupling term that mixes the gauge field to the external vector, ν μ . In spite of breaking Lorentz invariance in the particle frame, this model may preserve the CPT symmetry for a single particular choice of ν μ . Analyzing the dispersion relations, one verifies that the reduced model exhibits stability, but the causality can be jeopardized by some modes. The unitary of the gauge sector is assured without any restriction , while the scalar sector is unitary only in the space-like case. (author)
Velocity distribution of a driven inelastic one-component Maxwell gas.
Prasad, V V; Das, Dibyendu; Sabhapandit, Sanjib; Rajesh, R
2017-03-01
The nature of the velocity distribution of a driven granular gas, though well studied, is unknown as to whether it is universal or not, and, if universal, what it is. We determine the tails of the steady state velocity distribution of a driven inelastic Maxwell gas, which is a simple model of a granular gas where the rate of collision between particles is independent of the separation as well as the relative velocity. We show that the steady state velocity distribution is nonuniversal and depends strongly on the nature of driving. The asymptotic behavior of the velocity distribution is shown to be identical to that of a noninteracting model where the collisions between particles are ignored. For diffusive driving, where collisions with the wall are modeled by an additive noise, the tails of the velocity distribution is universal only if the noise distribution decays faster than exponential.
On solution of Maxwell's equations in axisymmetric domains with edges. Part II: Numerical aspects
International Nuclear Information System (INIS)
Nkemzi, Boniface
2003-10-01
In this paper we consider the Fourier-finite-element method for treating the Maxwell's equations in three-dimensional axisymmetric domains with reentrant edges. By means of partial Fourier analysis, the 3D BVP is decomposed into an infinite sequence of 2D variational equations in the plane meridian domain of the axisymmetric domain, a finite number of which is considered and treated using nodal H 1 -conforming finite elements. For domains with reentrant edges, the singular field method is employed to compensate the singular behavior of the solutions. Emphases are given to estimates of the Fourier-finite-element approximation error and convergence analysis in the H 1 -norm under different regularity assumptions. (author)
A Model for Solving the Maxwell Quasi Stationary Equations in a 3-Phase Electric Reduction Furnace
Directory of Open Access Journals (Sweden)
S. Ekrann
1982-10-01
Full Text Available A computer code has been developed for the approximate computation of electric and magnetic fields within an electric reduction furnace. The paper describes the numerical methods used to solve Maxwell's quasi-stationary equations, which are the governing equations for this problem. The equations are discretized by a staggered grid finite difference technique. The resulting algebraic equations are solved by iterating between computations of electric and magnetic quantities. This 'outer' iteration converges only when the skin depth is larger or of about the same magnitude as the linear dimensions of the computational domain. In solving for electric quantities with magnetic quantities being regarded as known, and vice versa, the central computational task is the solution of a Poisson equation for a scalar potential. These equations are solved by line successive overrelaxation combined with a rebalancing technique.
Kurz, S; Becker, U; Maisch, H
2001-05-01
This paper describes the state-of-the-art of dynamic simulation of electromechanical systems. Electromechanical systems can be split into electromagnetic and mechanical subsystems, which are described by Maxwell's equations and by Newton's law, respectively. Since such systems contain moving parts, the concepts of Lorentz and Galilean relativity are briefly addressed. The laws of physics are formulated in terms of (partial) differential equations. Numerical methods ultimately aim at linear systems of equations, which can be solved efficiently on digital computers. The various discretization methods for performing this task are discussed. Special emphasis is placed on domain decomposition as a framework for the coupling of different numerical methods such as the finite element method and the boundary element method. The paper concludes with descriptions of some applications of industrial relevance: a high performance injection valve and an electromechanical relay.
Einstein-Maxwell-axion theory: dyon solution with regular electric field
Energy Technology Data Exchange (ETDEWEB)
Balakin, Alexander B.; Zayats, Alexei E. [Kazan Federal University, Department of General Relativity and Gravitation, Institute of Physics, Kazan (Russian Federation)
2017-08-15
In the framework of the Einstein-Maxwell-axion theory we consider static spherically symmetric solutions which describe a magnetic monopole in the axionic environment. These solutions are interpreted as the solutions for an axionic dyon, the electric charge of which is composite, i.e. in addition to the standard central electric charge it includes an effective electric charge induced by the axion-photon coupling. We focus on the analysis of those solutions which are characterized by the electric field regular at the center. Special attention is paid to the solutions with the electric field that is vanishing at the center, and that has the Coulombian asymptote, and thus displays an extremum at some distant sphere. Constraints on the electric and effective scalar charges of such an object are discussed. (orig.)
The electrically charged BTZ black hole with self (anti-self) dual Maxwell field
International Nuclear Information System (INIS)
Kamata, M.; Koikawa, T.
1995-04-01
The Einstein-Maxwell equations with a negative cosmological constant Λ in 2 + 1 spacetime dimensions discussed by Banados, Teitelboim and Zanelli are solved by assuming a self (anti-self) dual equation E r-circumflex = ± B -circumflex , which is imposed on the orthonormal basis components of the electric field E r-circumflex and the magnetic field B -circumflex . This solution describes an electrically charged extra black hole with mass M=8πGQ 2 e , angular momentum J = ±8πGQ 2 e / modul Λ 1/2 and electric charge Q e . Although the coordinate components of the electric field E r and the magnetic field B have singularities on the horizon at r (4πGQ 2 e / modul Λ) 1/2 , the spacetime has the same value of constant negative curvature R = 6Λ as that of Banados et al. (author). 5 refs
Light deflection by charged wormholes in Einstein-Maxwell-dilaton theory
Jusufi, Kimet; Övgün, Ali; Banerjee, Ayan
2017-10-01
In this paper, we study the deflection of light by a class of charged wormholes within the context of the Einstein-Maxwell-dilaton theory. The primordial wormholes are predicted to exist in the early universe, where inflation is driven by the dilaton field. We perform our analysis through optical geometry using the Gibbons-Werner method (GW) by adopting the Gauss-Bonnet theorem and the standard geodesics approach. We report an interesting result for the deflection angle in leading-order terms—namely, the deflection angle increases due to the electric charge Q and the magnetic charge P , whereas it decreases due to the dilaton charge Σ . Finally, we confirm our findings by means of geodesics equations. Our computations show that the GW method gives an exact result in leading-order terms.
Maxwell-Chern-Simons vortices in a CPT-odd Lorentz-violating Higgs electrodynamics
International Nuclear Information System (INIS)
Casana, R.; Ferreira, M.M.; Hora, E. da; Neves, A.B.F.
2014-01-01
We study BPS vortices in a CPT-odd and Lorentz-violating Maxwell-Chern-Simons-Higgs (MCSH) electrodynamics attained from the dimensional reduction of the Carroll-Field-Jackiw-Higgs model. The Lorentz-violating parameter induces a pronounced behavior at origin (for the magnetic/electric fields and energy density) which is absent in the MCSH vortices. For some combination of the Lorentz-violating coefficients there always exists a sufficiently large winding number n 0 such that for all vertical stroke n vertical stroke ≥ vertical stroke n 0 vertical stroke the magnetic field flips sign, yielding two well-defined regions with opposite magnetic flux. However, the total magnetic flux remains quantized and proportional to the winding number. (orig.)
A Full Eulerian Vlasov-Maxwell Study of Turbulent Dynamics and Dissipation
TenBarge, J. M.; Juno, J.; Hakim, A.
2016-12-01
The development of a detailed understanding of turbulence in magnetized plasmas has been a long standing goal of the broader scientific community, both as a fundamental physics process and because of its applicability to a wide variety of phenomena. Turbulence in a magnetized plasma is the primary mechanism responsible for transforming energy at large injection scales into small-scale motions, which are ultimately dissipated as heat in systems such as the solar corona and wind. At large scales, the turbulence is well described by fluid models of the plasma; however, understanding the processes responsible for heating a weakly collisional plasma such as the solar wind requires a kinetic description. We present the first fully kinetic Eulerian Vlasov-Maxwell study of turbulence using the Gkeyll simulation code. We focus on the pristine distribution function dynamics that are possible with the Eulerian approach. We also present the signatures and form of dissipation as diagnosed via field-particle correlation functions.
Dynamics of Peregrine combs and Peregrine walls in an inhomogeneous Hirota and Maxwell-Bloch system
Wang, Lei; Wang, Zi-Qi; Sun, Wen-Rong; Shi, Yu-Ying; Li, Min; Xu, Min
2017-06-01
Under investigation in this paper is an inhomogeneous Hirota-Maxwell-Bloch (IHMB) system which can describe the propagation of optical solitons in an erbium-doped optical fiber. The breather multiple births (BMBs) are derived with periodically varying group velocity dispersion (GVD) coefficients. Under large periodic modulations in the GVD coefficient of IHMB system, the Peregrine comb (PC) solution is produced, which can be viewed as the limiting case of the BMBs. When the amplitude of the modulation satisfies a special condition, the Peregrine wall (PW) that can be regarded as an intermediate state between rogue wave and PC is obtained. The effects of the third-order dispersion on the spatiotemporal characteristics of PCs and PWs are studied. Our results may be useful for the experimental control and manipulation of the formation of generalized Peregrine rogue waves in inhomogeneous erbium-doped optical fiber.
The many faces of Maxwell, Dirac and Einstein equations a Clifford bundle approach
Rodrigues, Jr, Waldyr A
2016-01-01
This book is an exposition of the algebra and calculus of differential forms, of the Clifford and Spin-Clifford bundle formalisms, and of vistas to a formulation of important concepts of differential geometry indispensable for an in-depth understanding of space-time physics. The formalism discloses the hidden geometrical nature of spinor fields. Maxwell, Dirac and Einstein fields are shown to have representatives by objects of the same mathematical nature, namely sections of an appropriate Clifford bundle. This approach reveals unity in diversity and suggests relationships that are hidden in the standard formalisms and opens new paths for research. This thoroughly revised second edition also adds three new chapters: on the Clifford bundle approach to the Riemannian or semi-Riemannian differential geometry of branes; on Komar currents in the context of the General Relativity theory; and an analysis of the similarities and main differences between Dirac, Majorana and ELKO spinor fields. The exercises with solut...
Dimensional reduction of a Lorentz- and CPT-violating Maxwell-Chern-Simons model
Belich, H.; Ferreira, M. M.; Helayël-Neto, J. A.; Orlando, M. T.
2003-06-01
Taking as a starting point a Lorentz and CPT noninvariant Chern-Simons-like model defined in 1+3 dimensions, we proceed to realize its dimensional reduction to D=1+2. One then obtains a new planar model, composed by the Maxwell-Chern-Simons (MCS) sector, a Klein-Gordon massless scalar field, and a coupling term that mixes the gauge field to the external vector vμ. In spite of breaking Lorentz invariance in the particle frame, this model may preserve CPT symmetry for a single particular choice of vμ. Analyzing the dispersion relations, one verifies that the reduced model exhibits stability, but the causality can be jeopardized by some modes. The unitarity of the gauge sector is assured without any restriction, while the scalar sector is unitary only in the spacelike case.
Null hypersurface quantization, electromagnetic duality and asympotic symmetries of Maxwell theory
Bhattacharyya, Arpan; Hung, Ling-Yan; Jiang, Yikun
2018-03-01
In this paper we consider introducing careful regularization at the quantization of Maxwell theory in the asymptotic null infinity. This allows systematic discussions of the commutators in various boundary conditions, and application of Dirac brackets accordingly in a controlled manner. This method is most useful when we consider asymptotic charges that are not localized at the boundary u → ±∞ like large gauge transformations. We show that our method reproduces the operator algebra in known cases, and it can be applied to other space-time symmetry charges such as the BMS transformations. We also obtain the asymptotic form of the U(1) charge following from the electromagnetic duality in an explicitly EM symmetric Schwarz-Sen type action. Using our regularization method, we demonstrate that the charge generates the expected transformation of a helicity operator. Our method promises applications in more generic theories.
Maxwell, Yang-Mills, Weyl and eikonal fields defined by any null shear-free congruence
Kassandrov, Vladimir V.; Rizcallah, Joseph A.
We show that (specifically scaled) equations of shear-free null geodesic congruences on the Minkowski space-time possess intrinsic self-dual, restricted gauge and algebraic structures. The complex eikonal, Weyl 2-spinor, SL(2, ℂ) Yang-Mills and complex Maxwell fields, the latter produced by integer-valued electric charges (“elementary” for the Kerr-like congruences), can all be explicitly associated with any shear-free null geodesic congruence. Using twistor variables, we derive the general solution of the equations of the shear-free null geodesic congruence (as a modification of the Kerr theorem) and analyze the corresponding “particle-like” field distributions, with bounded singularities of the associated physical fields. These can be obtained in a straightforward algebraic way and exhibit nontrivial collective dynamics simulating physical interactions.
Wave energy flow conservation for propagation in inhomogeneous Vlasov-Maxwell equilibria
International Nuclear Information System (INIS)
Kull, H.J.; Berk, H.L.; Morrison, P.J.
1988-02-01
Wave energy flow conservation is demonstrated for Hermitian differential operators that arise in the Vlasov-Maxwell theory for propagation perpendicular to a magnetic field. The energy flow can be related to the bilinear concomitant, for a solution and its complex conjugate, by using the Lagrange identity of the operator. This bilinear form obeys a conservation law and is shown to describe the usual WKB energy flow for asymptotically homogeneous regions. The additivity and uniqueness of the energy flow expression is discussed for a general superposition of waves with real and complex wave numbers. Furthermore, a global energy conservation theorem is demonstrated for an inhomogeneity in one-dimension and generalized reflection and transmission coefficients are thereby obtained. 9 refs
An energy-conserving method for stochastic Maxwell equations with multiplicative noise
Hong, Jialin; Ji, Lihai; Zhang, Liying; Cai, Jiaxiang
2017-12-01
In this paper, it is shown that three-dimensional stochastic Maxwell equations with multiplicative noise are stochastic Hamiltonian partial differential equations possessing a geometric structure (i.e. stochastic multi-symplectic conservation law), and the energy of system is a conservative quantity almost surely. We propose a stochastic multi-symplectic energy-conserving method for the equations by using the wavelet collocation method in space and stochastic symplectic method in time. Numerical experiments are performed to verify the excellent abilities of the proposed method in providing accurate solution and preserving energy. The mean square convergence result of the method in temporal direction is tested numerically, and numerical comparisons with finite difference method are also investigated.
Einstein-Maxwell-axion theory: dyon solution with regular electric field
International Nuclear Information System (INIS)
Balakin, Alexander B.; Zayats, Alexei E.
2017-01-01
In the framework of the Einstein-Maxwell-axion theory we consider static spherically symmetric solutions which describe a magnetic monopole in the axionic environment. These solutions are interpreted as the solutions for an axionic dyon, the electric charge of which is composite, i.e. in addition to the standard central electric charge it includes an effective electric charge induced by the axion-photon coupling. We focus on the analysis of those solutions which are characterized by the electric field regular at the center. Special attention is paid to the solutions with the electric field that is vanishing at the center, and that has the Coulombian asymptote, and thus displays an extremum at some distant sphere. Constraints on the electric and effective scalar charges of such an object are discussed. (orig.)
Spherical space Bessel-Legendre-Fourier mode solver for Maxwell's wave equations
Alzahrani, Mohammed A.; Gauthier, Robert C.
2015-02-01
For spherically symmetric dielectric structures, a basis set composed of Bessel, Legendre and Fourier functions, BLF, are used to cast Maxwell's wave equations into an eigenvalue problem from which the localized modes can be determined. The steps leading to the eigenmatrix are reviewed and techniques used to reduce the order of matrix and tune the computations for particular mode types are detailed. The BLF basis functions are used to expand the electric and magnetic fields as well as the inverse relative dielectric profile. Similar to the common plane wave expansion technique, the BLF matrix returns the eigen-frequencies and eigenvectors, but in BLF only steady states, non-propagated, are obtained. The technique is first applied to a air filled spherical structure with perfectly conducting outer surface and then to a spherical microsphere located in air. Results are compared published values were possible.
Multiple scattering of polarized light: comparison of Maxwell theory and radiative transfer theory.
Voit, Florian; Hohmann, Ansgar; Schäfer, Jan; Kienle, Alwin
2012-04-01
For many research areas in biomedical optics, information about scattering of polarized light in turbid media is of increasing importance. Scattering simulations within this field are mainly performed on the basis of radiative transfer theory. In this study a polarization sensitive Monte Carlo solution of radiative transfer theory is compared to exact Maxwell solutions for all elements of the scattering Müller matrix. Different scatterer volume concentrations are modeled as a multitude of monodisperse nonabsorbing spheres randomly positioned in a cubic simulation volume which is irradiated with monochromatic incident light. For all Müller matrix elements effects due to dependent scattering and multiple scattering are analysed. The results are in overall good agreement between the two methods with deviations related to dependent scattering being prominent for high volume concentrations and high scattering angles.
Lifshitz black branes and DC transport coefficients in massive Einstein-Maxwell-dilaton gravity
Kuang, Xiao-Mei; Papantonopoulos, Eleftherios; Wu, Jian-Pin; Zhou, Zhenhua
2018-03-01
We construct analytical Lifshitz massive black brane solutions in massive Einstein-Maxwell-dilaton gravity theory. We also study the thermodynamics of these black brane solutions and obtain the thermodynamical stability conditions. On the dual nonrelativistic boundary field theory with Lifshitz symmetry, we analytically compute the DC transport coefficients, including the electric conductivity, thermoelectric conductivity, and thermal conductivity. The novel property of our model is that the massive term supports the Lifshitz black brane solutions with z ≠1 in such a way that the DC transport coefficients in the dual field theory are finite. We also find that the Wiedemann-Franz law in this dual boundary field theory is violated, which indicates that it may involve strong interactions.
Autonomous quantum Maxwell's demon based on two exchange-coupled quantum dots
Ptaszyński, Krzysztof
2018-01-01
I study an autonomous quantum Maxwell's demon based on two exchange-coupled quantum dots attached to the spin-polarized leads. The principle of operation of the demon is based on the coherent oscillations between the spin states of the system which act as a quantum iSWAP gate. Due to the operation of the iSWAP gate, one of the dots acts as a feedback controller which blocks the transport with the bias in the other dot, thus inducing the electron pumping against the bias; this leads to the locally negative entropy production. Operation of the demon is associated with the information transfer between the dots, which is studied quantitatively by mapping the analyzed setup onto the thermodynamically equivalent auxiliary system. The calculated entropy production in a single subsystem and information flow between the subsystems are shown to obey a local form of the second law of thermodynamics, similar to the one previously derived for classical bipartite systems.
Maxwell: la teoría electromagnética de la luz
Directory of Open Access Journals (Sweden)
Gabàs Masip, Joel
2015-10-01
Full Text Available This article aims to explain the context in which the electromagnetic wave theory was developed and light was identified as an electromagnetic wave. With this aim, it explores Maxwell’s life and times, focusing in particular on the state of knowledge of optics, electricity and magnetism.Este artículo pretende explicar en qué contexto se desarrolló la teoría de las ondas electromagnéticas y se identificó la luz como una de ellas. Para ello se hace un análisis de la figura de Maxwell y su tiempo, haciendo especial hincapié en el estado del conocimiento en óptica, electricidad y magnetismo.
The general Lie group and similarity solutions for the one-dimensional Vlasov-Maxwell equations
Roberts, D.
1985-01-01
The general Lie point transformation group and the associated reduced differential equations and similarity forms for the solutions are derived here for the coupled (nonlinear) Vlasov-Maxwell equations in one spatial dimension. The case of one species in a background is shown to admit a larger group than the multispecies case. Previous exact solutions are shown to be special cases of the above solutions, and many of the new solutions are found to constrain the form of the distribution function much more than, for example, the BGK solutions do. The individual generators of the Lie group are used to find the possible subgroups. Finally, a simple physical argument is given to show that the asymptotic solution for a one-species, one-dimensional plasma is one of the general similarity solutions.
Vidal-Sallé, Emmanuelle; Chassagne, Pierre
2007-06-01
This paper presents a nonlinear viscoelastic orthotropic constitutive equation applied to wood material. The proposed model takes into account mechanical and mechanosorptive creep via a 3D stress ratio and moisture change rate for a cylindrical orthotropic material. Orthotropic frame is based on the grain direction (L), radial (R) and hoop (T) directions, which are natural wood directions. Particular attention is taken to ensure the model to fulfill the necessary dissipation conditions. It is based on a rheological generalized Maxwell model with two elements in parallel in addition with a single linear spring taking into account the long term response. The proposed model is implemented in the finite element code ABAQUS/Standard® via a user subroutine UMAT and simple example is shown to demonstrate the capability of the proposed model. Future works would deal with damage and fracture prediction for wooden structures submitted to climate variations and mechanical loading.
Li, Xin; Wang, Shu; Feng, Yue-Hong
2018-01-01
We study the stability of smooth solutions near non-constant equilibrium states for a bipolar full compressible Navier-Stokes-Maxwell system in a three-dimensional torus T= (R/Z)^3 . This system is quasilinear hyperbolic-parabolic. In the first part, by using the maximum principle, we find a non-constant steady state solution with small amplitude for this system. In the second part, with the help of suitable choices of symmetrizers and classic energy estimates, we prove that global smooth solutions exist and converge to the non-constant steady states as the time goes to infinity. As a byproduct, we obtain the global stability for the bipolar full compressible Navier-Stokes-Poisson system.
Maxwell's equations in divergence form for general media with applications to MHD
International Nuclear Information System (INIS)
Van Putten, M.H.P.M.
1991-01-01
Maxwell's equations in media with general constitutive relations are reformulated in covariant form as a system of divergence equations without constraints. Our reformulation enables us to express general electro-magneto-fluid problems as hyperbolic systems in divergence form. We illustrate this method on the MHD problem. In the absence of constraints, a general representation is derived for the characteristic form for first-order systems of quasi-linear partial differential equations in vector fields and scalars. Using this covariant formulation of characteristics, we find that the principle of covariance imposes a very rigid structure on the infinitesimally small amplitude waves in MHD. To demonstrate the power of the reformulation, we study numerically ultra-relativistic wave breaking using the divergence formulation of MHD. (orig.)
Faraday, Maxwell, and the electromagnetic field how two men revolutionized physics
Forbes, Nancy
2014-01-01
The story of two brilliant nineteenth-century scientists who discovered the electromagnetic field, laying the groundwork for the amazing technological and theoretical breakthroughs of the twentieth century Two of the boldest and most creative scientists of all time were Michael Faraday (1791-1867) and James Clerk Maxwell (1831-1879). This is the story of how these two men - separated in age by forty years - discovered the existence of the electromagnetic field and devised a radically new theory which overturned the strictly mechanical view of the world that had prevailed since Newton's time. The authors, veteran science writers with special expertise in physics and engineering, have created a lively narrative that interweaves rich biographical detail from each man's life with clear explanations of their scientific accomplishments. Faraday was an autodidact, who overcame class prejudice and a lack of mathematical training to become renowned for his acute powers of experimental observation, technological skil...
Maxwell McCombs, 35 years of a limitless theory: a profile
Directory of Open Access Journals (Sweden)
Pedro Paulo Procópio
2008-06-01
Full Text Available This paper intends to draw a profile of 35 years of agenda-setting theory continuous development, as well as to present a parallel with its creator, Professor Maxwell McCombs. The approach adopted is to contextualize the agenda-setting theory with some trends that had influence on its appearance and development during the last three decades. This profile also documents some statements of Professor McCombs´ participation in his first visit to Brazil, including his opening session speech at the 5th Congress of the Brazilian Society of Journalism Researchers – SBPJOR – and the lecture he gave in the Postgraduate Program of Communication Studies at the Federal University of Pernambuco, Brazil. Both events occurred in November 2007. Until now, this is the first and only visit by Professor McCombs to Brazil.
Macke, Andreas; Mishchenko, Michael I.
2015-01-01
The 15th Electromagnetic and Light Scattering Conference (ELS-XV) was held in Leipzig, Germany from 21 to 26 of June 2015. This conference built on the great success of the previous meetings held in Amsterdam (1995), Helsinki(1997) [2], New York City(1998) [3], Vigo (1999),Halifax (2000), Gainesville (2002), Bremen (2003), Salobreña (2005), St. Petersburg (2006), Bodrum (2007), Hatfield (2008), Helsinki (2010), Taormina (2011), and Lille as well as the workshops held in Bremen (1996,1998) and Moscow (1997). As usual, the main objective of this conference was to bring together scientists, engineers, and PhD students studying various aspects of electromagnetic scattering and to provide a relaxed atmosphere for in-depth discussion of theory, measurements, and applications. Furthermore, ELS-XV supported the United Nations "Year of Light" and celebrated the150th anniversary of Maxwell's electromagnetics. Maxwell's paper on "A Dynamical Theory of the Electromagnetic Field" was published in1865 and has widely been acknowledged as one of the supreme achievements in the history of science. The conference was attended by136 scientists from 22 countries. The scientific program included two plenary lectures, 16 invited reviews, 88 contributed oral talks, and 70 poster presentations. The program and the abstracts of conference presentations are available at the conference website http://www.els-xv-2015.net/home.html. Following the well-established ELS practice and with Elsevier's encouragement, we solicited full-size papers for a topical issue of the Journal of Quantitative Spectroscopy and Radiative Transfer (JQSRT). The result of this collective effort is now in the reader's hands. As always, every invited review and regular paper included in this topical issue has undergone the same rigorous peer review process as any other manuscript published in the JQSRT.
Allie-Ebrahim, Tariq; Zhu, Qingyu; Bräuer, Pierre; Moggridge, Geoff D; D'Agostino, Carmine
2017-06-21
The Maxwell-Stefan model is a popular diffusion model originally developed to model diffusion of gases, which can be considered thermodynamically ideal mixtures, although its application has been extended to model diffusion in non-ideal liquid mixtures as well. A drawback of the model is that it requires the Maxwell-Stefan diffusion coefficients, which are not based on measurable quantities but they have to be estimated. As a result, numerous estimation methods, such as the Darken model, have been proposed to estimate these diffusion coefficients. However, the Darken model was derived, and is only well defined, for binary systems. This model has been extended to ternary systems according to two proposed forms, one by R. Krishna and J. M. van Baten, Ind. Eng. Chem. Res., 2005, 44, 6939-6947 and the other by X. Liu, T. J. H. Vlugt and A. Bardow, Ind. Eng. Chem. Res., 2011, 50, 10350-10358. In this paper, the two forms have been analysed against the ideal ternary system of methanol/butan-1-ol/propan-1-ol and using experimental values of self-diffusion coefficients. In particular, using pulsed gradient stimulated echo nuclear magnetic resonance (PGSTE-NMR) we have measured the self-diffusion coefficients in various methanol/butan-1-ol/propan-1-ol mixtures. The experimental values of self-diffusion coefficients were then used as the input data required for the Darken model. The predictions of the two proposed multicomponent forms of this model were then compared to experimental values of mutual diffusion coefficients for the ideal alcohol ternary system. This experimental-based approach showed that the Liu's model gives better predictions compared to that of Krishna and van Baten, although it was only accurate to within 26%. Nonetheless, the multicomponent Darken model in conjunction with self-diffusion measurements from PGSTE-NMR represents an attractive method for a rapid estimation of mutual diffusion in multicomponent systems, especially when compared to exhaustive
Gauthier, Robert C.; Alzahrani, Mohammed A.; Jafari, Seyed Hamed
2015-02-01
The plane wave expansion (PWM) technique applied to Maxwell's wave equations provides researchers with a supply of information regarding the optical properties of dielectric structures. The technique is well suited for structures that display a linear periodicity. When the focus is directed towards optical resonators and structures that lack linear periodicity the eigen-process can easily exceed computational resources and time constraints. In the case of dielectric structures which display cylindrical or spherical symmetry, a coordinate system specific set of basis functions have been employed to cast Maxwell's wave equations into an eigen-matrix formulation from which the resonator states associated with the dielectric profile can be obtained. As for PWM, the inverse of the dielectric and field components are expanded in the basis functions (Fourier-Fourier-Bessel, FFB, in cylindrical and Fourier- Bessel-Legendre, BLF, in spherical) and orthogonality is employed to form the matrix expressions. The theoretical development details will be presented indicating how certain mathematical complications in the process have been overcome and how the eigen-matrix can be tuned to a specific mode type. The similarities and differences in PWM, FFB and BLF are presented. In the case of structures possessing axial cylindrical symmetry, the inclusion of the z axis component of propagation constant makes the technique applicable to photonic crystal fibers and other waveguide structures. Computational results will be presented for a number of different dielectric geometries including Bragg ring resonators, cylindrical space slot channel waveguides and bottle resonators. Steps to further enhance the computation process will be reported.
2015 Elections to Staff Council
Staff Asscociation
2015-01-01
Make your voice heard, support your candidates! Be many to vote and to elect the new Staff Council. By doing so, you will be encouraging the men and women who will represent you over the next two years and they will without doubt appreciate your gratitude. The voting takes place from the 26th of October to the 9th of November, at noon at https://ap-vote.web.cern.ch/elections-2015. Elections Timetable Monday 9 November, at noon Closing date for voting Monday 16 and Monday 23 November, publication of the results in Echo Tuesday 8 December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure will be monitored by the Election Committee, which is also in charge of announcing the results in Echo on 16 and 24 November. Candidates for the 2015 elections
Towards mobile staff members management
Encheva, Sylvia
2017-07-01
Todays project management requires a number of abilities which involve finding quick solutions to shortage of staff members with possession of specific qualities. When persons with team responsibilities are under pressure or due to various circumstances are unable to perform exhaustive search in databases, an interactive visualization tool can come in quite handy in finding good solutions unforeseen occurrences. In particular we propose application of selected graphs for facilitating mobile human resource management.
Managing a multicultural radiology staff.
Davidhizar, R; Dowd, S; Giger, J
1997-01-01
Opportunities for minorities in healthcare increased with the Civil Rights movement in the 1960s. More recently, funds from the U.S. Public Health Service have been targeted toward disadvantaged minorities. The workforce in healthcare, and in business in general, has become increasingly multicultural. Much of the literature in healthcare management lacks practical guidelines for managing a diverse workforce. Communication, both verbal and nonverbal, and culture are closely intertwined. Managers, as they develop multicultural teams, will need to understand how culture influences communication in their organizations. Space, spatial behavior, and cultural attitudes influence people's behavior. This is a particularly important consideration for a radiology staff, which must often work in close quarters. For some cultural groups, the family as an organization has more significance than even personal, work-related or national causes. People's orientation to time, whether for the past, present or future, is usually related to the culture in which they grew up. Again, this may become an important issue for a radiology administrator whose organization must run punctually and time-efficiently. How patients feel about their environment, whether they believe they are in control or believe in an external locus of control, is of particular interest to those who attempt therapeutic changes in a patient's healthcare. Does the patient believe that illness is divine will or that suffering is intrinsic to the human condition? There is increasing research in the United States to show that people do differ biologically according to race. Such differences exist among patients as well as among staff members. It has been popular to assume that differences among races do not exist. Unfortunately such an attitude does not allow for different attributes and responses of individuals. Managing a multicultural staff presents a challenge to administrators who must be skilled in working with
2015 Elections to Staff Council
Staff Association
2015-01-01
Elections Timetable Monday 26 October, at noon Start date for voting Monday 9 November, at noon Closing date for voting Monday 16 and Monday 23 November, publication of the results in Echo Monday 23 and Tuesday 24 November Staff Association Assizes Tuesday 1st December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure will be monitored by the Election Committee, which is also in charge of announcing the results in Echo on 16 and 24 November. During its meeting of March 17 2015, the Staff Council approved the election rules, which define the allocation of seats in each department, as follows: Number of seats in the electoral colleges Departments BE EN TE DG/DGS FP GS HR/PF IT PH Career paths AA - D 2 3 3 1 1 2 1 1 2 Career paths E - G 2 2 2 1 1 1 1 2 3 Global CERN Career paths AA - G 14 Number of seats for fellows representatives Global CERN 5 For more informat...
2015 Elections to Staff Council
Staff Association
2015-01-01
Elections Timetable Monday 21 September, at noon Start date for receipt of the application Friday 16 October, at noon Closing date for receipt of the applications Monday 26 October, at noon Start date for voting Monday 9 November, at noon Closing date for voting Monday 16 and Monday 23 November, publication of the results in Echo Monday 23 and Tuesday 24 November Staff Association Assizes Tuesday 1st December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure will be monitored by the Election Committee, which is also in charge of announcing the results in Echo on 16 and 24 November. During its meeting of March 17 2015, the Staff Council approved the election rules, which define the allocation of seats in each department, as follows: Number of seats in the electoral colleges Departments BE EN TE DG/DGS FP GS HR/PF IT PH Career paths AA - D 2 3 3 1 1 2 1 1 2 Career paths E - G 2 2 2 1 1 1 1 2 3 ...
Strategies and best practices for staff renewal
International Nuclear Information System (INIS)
Cottingham, C.
2007-01-01
This paper discusses the strategies and best practices for staff renewal in the electricity sector. Strategic initiatives for staff renewal include strategic recruiting, succession planning, employee relations, knowledge management and strategic partnerships
The Joint Staff Officer's Guide 2000
National Research Council Canada - National Science Library
2000-01-01
The Joint Forces Staff College (JFSC) educates staff officers and other leaders in joint operational-level planning and warfighting and instills a commitment to joint, multinational, and interagency teamwork, attitudes, and perspectives...
Staff radiation exposure in radiation diagnostics
International Nuclear Information System (INIS)
Khakimova, N.U.; Malisheva, E.Yu.; Shosafarova, Sh.G.
2010-01-01
Present article is devoted to staff radiation exposure in radiation diagnostics. Data on staff radiation exposure obtained during 2005-2008 years was analyzed. It was found that average individual doses of staff of various occupations in Dushanbe city for 2008 year are at 0.29-2.16 mSv range. They are higher than the average health indicators but lower than maximum permissible dose. It was defined that paramedical personnel receives the highest doses among the various categories of staff.
Become a staff delegate: why not you?
Association du personnel
2009-01-01
Following a decision taken at the Staff Association General Assembly in May 2008, staff delegates are elected in the autumn of odd-numbered years. The next elections which will lead to a total renewal of the Staff Council will thus take place in November 2009. Will you be a candidate?
Get the Staff You Need This Summer.
Phillips, Christy L.
1997-01-01
Strategies for recruiting camp staff include tailoring messages to the needs and interests of prospective staff; utilizing former staff; hiring older workers; encouraging parents, former campers, and special interest groups to volunteer; and offering competitive pay. Provides an example of a target population (Generation X, born 1963-83) and key…
Strengthening Bullying Prevention through School Staff Connectedness
O'Brennan, Lindsey M.; Waasdorp, Tracy E.; Bradshaw, Catherine P.
2014-01-01
The growing concern about bullying and school violence has focused national attention on various aspects of school climate and school connectedness. The current study examined dimensions of staff connectedness (i.e., personal, student, staff, and administration) in relation to staff members' comfort intervening in bullying situations (e.g.,…
Self Efficacy among University Academic Staff
African Journals Online (AJOL)
There was no significant difference between teaching staff and professional librarians on collective educators' self efficacy but significant difference existed between male and female academic staff on collective educators' self efficacy. The implication of the result in terms of collaborative work among academic staff was ...
Short Communication Employee -Driven Staff Training and ...
African Journals Online (AJOL)
This paper examines the concept of staff training and development within the South African context. The changing labour legislation in South Africa makes it mandatory for the employer to provide training and development. However, staff have an important role to play in staff training and development. The paper gives an ...
28 CFR 551.32 - Staff supervision.
2010-07-01
... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Staff supervision. 551.32 Section 551.32 Judicial Administration BUREAU OF PRISONS, DEPARTMENT OF JUSTICE INSTITUTIONAL MANAGEMENT MISCELLANEOUS Inmate Organizations § 551.32 Staff supervision. (a) The Warden shall appoint a staff member as the...
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Staff. 400.105 Section 400.105... Board Procedures § 400.105 Staff. (a) Executive Director. The Executive Director of the Board advises... with respect to the administration of the Board's actions, directs the activities of the staff, and...
2010-01-01
... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Staff. 500.105 Section 500.105... LOAN PROGRAM Board Procedures § 500.105 Staff. (a) Executive Director. The Executive Director of the... direction with respect to the administration of the Board's actions, directs the activities of the staff...
2010-04-01
... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Staff. 900.5 Section 900.5 Employees' Benefits JOINT BOARD FOR THE ENROLLMENT OF ACTUARIES STATEMENT OF ORGANIZATION § 900.5 Staff. (a) The... the Act and performs such other functions as the Board may delegate to him. (b) Members of the staffs...
2010-01-01
... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Staff. 1310.6 Section 1310.6 Aeronautics... GUARANTEED LOAN § 1310.6 Staff. (a) Executive Director. The Executive Director advises and assists the Board... administration of the Board's actions, directs the activities of the staff, and performs such other duties as the...
Improving Staff Productivity in Mental Health Centers.
Southern Regional Education Board, Atlanta, GA.
This guide is concerned with productivity measurement and improvement in mental health centers, and focuses on the relationship between service outputs and available clinical staff, i.e., staff productivity. Staff productivity measures are described as useful in identifying existing levels of productivity, making comparisons to determine the…
Vogman, Genia
Plasmas are made up of charged particles whose short-range and long-range interactions give rise to complex behavior that can be difficult to fully characterize experimentally. One of the most complete theoretical descriptions of a plasma is that of kinetic theory, which treats each particle species as a probability distribution function in a six-dimensional position-velocity phase space. Drawing on statistical mechanics, these distribution functions mathematically represent a system of interacting particles without tracking individual ions and electrons. The evolution of the distribution function(s) is governed by the Boltzmann equation coupled to Maxwell's equations, which together describe the dynamics of the plasma and the associated electromagnetic fields. When collisions can be neglected, the Boltzmann equation is reduced to the Vlasov equation. High-fidelity simulation of the rich physics in even a subset of the full six-dimensional phase space calls for low-noise high-accuracy numerical methods. To that end, this dissertation investigates a fourth-order finite-volume discretization of the Vlasov-Maxwell equation system, and addresses some of the fundamental challenges associated with applying these types of computationally intensive enhanced-accuracy numerical methods to phase space simulations. The governing equations of kinetic theory are described in detail, and their conservation-law weak form is derived for Cartesian and cylindrical phase space coordinates. This formulation is well known when it comes to Cartesian geometries, as it is used in finite-volume and finite-element discretizations to guarantee local conservation for numerical solutions. By contrast, the conservation-law weak form of the Vlasov equation in cylindrical phase space coordinates is largely unexplored, and to the author's knowledge has never previously been solved numerically. Thereby the methods described in this dissertation for simulating plasmas in cylindrical phase space
The operating staff of nuclear power plants
International Nuclear Information System (INIS)
Schlegel, G.; Christ, W.
1988-01-01
The training of its staff is one of the pillars of the safe and economical operation of a power plant. This is why power plant owners began to systematically train their staff already in the 50s, and why they created central training facilities. Staff members who have undergone this training make an indispensable contribution to the acceptedly high safety and availability of German power plants. The substantial cost of creating training facilities and of schooling plant staff is considered to be an investment for the future. Low labour turnover permits careful observation and development of staff and leads to a high standard of knowledge and experience. (orig./HSCH) [de
Bosanquet, Katharine; Adamson, Joy; Atherton, Katie; Bailey, Della; Baxter, Catherine; Beresford-Dent, Jules; Birtwistle, Jacqueline; Chew-Graham, Carolyn; Clare, Emily; Delgadillo, Jaime; Ekers, David; Foster, Deborah; Gabe, Rhian; Gascoyne, Samantha; Haley, Lesley; Hamilton, Jahnese; Hargate, Rebecca; Hewitt, Catherine; Holmes, John; Keding, Ada; Lewis, Helen; McMillan, Dean; Meer, Shaista; Mitchell, Natasha; Nutbrown, Sarah; Overend, Karen; Parrott, Steve; Pervin, Jodi; Richards, David A; Spilsbury, Karen; Torgerson, David; Traviss-Turner, Gemma; Trépel, Dominic; Woodhouse, Rebecca; Gilbody, Simon
2017-11-01
Depression in older adults is common and is associated with poor quality of life, increased morbidity and early mortality, and increased health and social care use. Collaborative care, a low-intensity intervention for depression that is shown to be effective in working-age adults, has not yet been evaluated in older people with depression who are managed in UK primary care. The CollAborative care for Screen-Positive EldeRs (CASPER) plus trial fills the evidence gap identified by the most recent guidelines on depression management. To establish the clinical effectiveness and cost-effectiveness of collaborative care for older adults with major depressive disorder in primary care. A pragmatic, multicentred, two-arm, parallel, individually randomised controlled trial with embedded qualitative study. Participants were automatically randomised by computer, by the York Trials Unit Randomisation Service, on a 1 : 1 basis using simple unstratified randomisation after informed consent and baseline measures were collected. Blinding was not possible. Sixty-nine general practices in the north of England. A total of 485 participants aged ≥ 65 years with major depressive disorder. A low-intensity intervention of collaborative care, including behavioural activation, delivered by a case manager for an average of six sessions over 7-8 weeks, alongside usual general practitioner (GP) care. The control arm received only usual GP care. The primary outcome measure was Patient Health Questionnaire-9 items score at 4 months post randomisation. Secondary outcome measures included depression severity and caseness at 12 and 18 months, the EuroQol-5 Dimensions, Short Form questionnaire-12 items, Patient Health Questionnaire-15 items, Generalised Anxiety Disorder-7 items, Connor-Davidson Resilience Scale-2 items, a medication questionnaire, objective data and adverse events. Participants were followed up at 12 and 18 months. In total, 485 participants were randomised (collaborative
Liu, Yen; Vinokur, Marcel; Wang, Z. J.
2004-01-01
A three-dimensional, high-order, conservative, and efficient discontinuous spectral volume (SV) method for the solutions of Maxwell's equations on unstructured grids is presented. The concept of discontinuous 2nd high-order loca1 representations to achieve conservation and high accuracy is utilized in a manner similar to the Discontinuous Galerkin (DG) method, but instead of using a Galerkin finite-element formulation, the SV method is based on a finite-volume approach to attain a simpler formulation. Conventional unstructured finite-volume methods require data reconstruction based on the least-squares formulation using neighboring cell data. Since each unknown employs a different stencil, one must repeat the least-squares inversion for every cell at each time step, or to store the inversion coefficients. In a high-order, three-dimensional computation, the former would involve impractically large CPU time, while for the latter the memory requirement becomes prohibitive. In the SV method, one starts with a relatively coarse grid of triangles or tetrahedra, called spectral volumes (SVs), and partition each SV into a number of structured subcells, called control volumes (CVs), that support a polynomial expansion of a desired degree of precision. The unknowns are cell averages over CVs. If all the SVs are partitioned in a geometrically similar manner, the reconstruction becomes universal as a weighted sum of unknowns, and only a few universal coefficients need to be stored for the surface integrals over CV faces. Since the solution is discontinuous across the SV boundaries, a Riemann solver is thus necessary to maintain conservation. In the paper, multi-parameter and symmetric SV partitions, up to quartic for triangle and cubic for tetrahedron, are first presented. The corresponding weight coefficients for CV face integrals in terms of CV cell averages for each partition are analytically determined. These discretization formulas are then applied to the integral form of
Convective transport in a porous medium layer saturated with a Maxwell nanofluid
Directory of Open Access Journals (Sweden)
J.C. Umavathi
2016-01-01
Full Text Available A linear and weakly non-linear stability analys is has been carried out to study the onset of convection in a horizontal layer of a porous medium saturated with a Maxwell nanofluid. To simulate the momentum equation in porous media, a modified Darcy–Maxwell nanofluid model incorporating the effects of Brownian motion and thermophoresis has been used. A Galerkin method has been employed to investigate the stationary and oscillatory convections; the stability boundaries for these cases are approximated by simple and useful analytical expressions. The stability of the system is investigated by varying various parameters viz., nanoparticle concentration Rayleigh number, Lewis number, modified diffusivity ratio, porosity, thermal capacity ratio, viscosity ratio, conductivity ratio, Vadász number and relaxation parameter. A representation of Fourier series method has been used to study the heat and mass transport on the non-linear stability analysis. The effect of transient heat and mass transport on various parameters is also studied. It is found that for stationary convection Lewis number, viscosity ratio and conductivity ratio have a stabilizing effect while nanoparticle concentration Rayleigh number Rn destabilizes the system. For oscillatory convection we observe that the conductivity ratio stabilizes the system whereas nanoparticle concentration Rayleigh number, Lewis number, Vadász number and relaxation parameter destabilize the system. The viscosity ratio increases the thermal Rayleigh number for oscillatory convection initially thus delaying the onset of convection and later decreases thus advancing the onset of convection hence showing a dual effect. For steady finite amplitude motions, the heat and mass transport decreases with an increase in the values of nanoparticle concentration Rayleigh number, Lewis number, viscosity ratio and conductivity ratio. The mass transport increases with an increase in Vadász number and relaxation
2011 Elections to Staff Council
Association du personnel
2011-01-01
Elections Timetable Starting with Echo of 26 September, posters, etc. call for applications Wednesday 26 October, at noon closing date for receipt of the application Monday 31 October, at noon start date for voting Monday 14 November, at noon closing date for voting Monday 21 November, publication of the results in Echo Tuesday 22 and Wednesday 29 November Staff Association Assizes Tuesday 6 December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure will be monitored by the Election Committee, which is also in charge of announcing the results in Echo on 21 November. In its meeting on 19 September 2011, the Electoral Commission decided on the following distribution of seats in colleges 0.1 to 0.6: Sector Department Career path AA – A – B – C – D Career path E – F – G – H Accelerators and Technology BE TE EN Electoral college 0.1 18 si&e...
2013 Elections to Staff Council
Staff Association
2013-01-01
Elections Timetable Starting with Echo of 16 September, posters, etc. call for applications Monday 21 October, at noon closing date for receipt of the applications Monday 28 October, at noon start date for voting Monday 11 November, at noon closing date for voting Monday 18 and Monday 25 November, publication of the results in Echo Tuesday 19 November Staff Association Assizes Tuesday 3 December, at 10.00 a.m. first meeting of the new Staff Council and election of the new Executive Committee The voting procedure is monitored by the Election Committee, which is also in charge of announcing the results in Echo on 18 and 25 November. n its meeting on 11 September 2013, the Electoral Commission decided on the following distribution of seats in colleges O.1 to O.6: Sectors Departments Career paths AA – A – B – C – D Career paths E – F – G – H Accelerators and Technology BE TE EN Electoral college 0.1 13 si&...
DEFF Research Database (Denmark)
Webb, Garry; Sørensen, Mads Peter; Brio, Moysey
2004-01-01
to circumvent this problem, non-canonical Poisson bracket formulations of the equations are obtained in which the electric field is one of the non-canonical variables. Noether's theorem, and the Lie point symmetries admitted by the equations are used to obtain four conservation laws, including......The vector Maxwell equations of nonlinear optics coupled to a single Lorentz oscillator and with instantaneous Kerr nonlinearity are investigated by using Lie symmetry group methods. Lagrangian and Hamiltonian formulations of the equations are obtained. The aim of the analysis is to explore...... the properties of Maxwell's equations in nonlinear optics, without resorting to the commonly used nonlinear Schr\\"odinger (NLS) equation approximation in which a high frequency carrier wave is modulated on long length and time scales due to nonlinear sideband wave interactions. This is important in femto...
2015-01-01
Discussion meeting organised by Professor Anatoly Zayats, Professor John Ellis and Professor Roy Pike. 16-17 November 2015 at The Royal Society 6-9 Carlton House Terrace, London Event details The unification of electric and magnetic fields about 150 years ago in what is now known as electromagnetic theory expressed in Maxwell's Equations has enabled virtually all modern electrical, electronic, radio and photonic technologies. What new scientific breakthroughs and applications will unification with the other fields provide? This meeting brings together high-energy, optical, quantum and solid-state physicists to discuss recent developments enabled by Maxwell's Equations and will try to predict future innovations. Attending this event This event is intended for researchers in relevant fields and is free to attend. There are a limited number of places and registration is essential. For more information, visit the Royal Society event website.
Accurate Measurement of ‘Q’ Factor of An Inductive Coil Using a Modified Maxwell Wein Bridge Network
Directory of Open Access Journals (Sweden)
Subrata CHATTOPADHYAY
2009-06-01
Full Text Available The Q factor of a coil can be measured by measuring accurately the inductance and effective resistance of the coil for a specific signal. The inductance of an inductive coil is generally measured by usual inductive circuit like Maxwell-Wein Bridge, Hay Bridge etc. which suffer from error due to stray capacitance between bridge nodal point and ground and stray inductance of the inductive coil. The conventional Wagner Earth Technique is not suitable for continuous measurement. In the present paper, a modified operational amplifier based Maxwell-Wein Bridge measurement technique has been proposed in which stray capacitance and stray inductance are minimized. The experiment is done for different value of known inductance & Q factor for a specific signal. The linear characteristic with a good repeatability, linearity and variable sensitivity has been described.
Neuner-Jehle, Stefan; Grüninger, Ueli; Schmid, Margareta
2014-01-01
Le programme Coaching Santé du Collège de médecine de premier recours (CMPR) facilite le conseil de santé en matière de prévention, thérapie et réhabilitation (par exemple, alcool, tabac). Le patient devient l’acteur principal, choisit lui-même ses objectifs et le médecin le soutient (fonction de « coach »). Le Coaching Santé comprend des algorithmes simples et un instrument visuel pour soutenir les quatre étapes du programme : sensibiliser-motiver-planifier-accompagner. Il a été testé ave...
Directory of Open Access Journals (Sweden)
Fanny Colonna
2007-07-01
Full Text Available Il s’agit d’un livre vraiment important. Passionnant à lire, même si pas facile pour qui ne connaît pas l’histoire et les données marocaines en détails et stimulant aussi. Pour plusieurs raisons : - Parce qu’on ne sait en général sur ce fameux collège d’Azrou que quelques stéréotypes, des on-dits (la politique berbère de la France, le rêve d’un Berberistan, puis l’attentat de Skirat, etc… et qu’on dispose ici, au contraire, en 400 et quelques pages, d’un dossier complet, complexe, contradic...
Weyl type N solutions with null electromagnetic fields in the Einstein-Maxwell p-form theory
Czech Academy of Sciences Publication Activity Database
Kuchynka, Martin; Pravdová, Alena
2017-01-01
Roč. 49, č. 5 (2017), č. článku 71. ISSN 0001-7701 R&D Projects: GA ČR GA13-10042S Institutional support: RVO:67985840 Keywords : Einstein–Maxwell equations * Weyl type N spacetimes * Kundt spacetimes Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 1.618, year: 2016 https://link.springer.com/article/10.1007/s10714-017-2234-7
International Nuclear Information System (INIS)
Avetisyan, Yu. A.; Trifonov, E. D.
2008-01-01
We give a general formulation of the semiclassical approach to solving the problem of interaction between a Bose-Einstein condensate of dilute gas and electromagnetic radiation without using the commonly applied mean-field approximation. We suggest variants of the systems of Maxwell-Schroedinger equations whose solution describes such effects as superradiant light scattering, light beam amplification, atomic wave (atomic laser) amplification, induced transparency, and reduction in the group velocity of light
International Nuclear Information System (INIS)
Artru, X.; Fayolle, D.
2001-01-01
For a monopole, the analogue of the Lorentz equation in matter is shown to be f = g (H-v centre dot D). Dual-symmetric Maxwell equations, for matter containing hidden magnetic charge in addition to electric ones, are given. They apply as well to ordinary matter if the particles possess T-violating electric dipole moments. Two schemes of experiments for the detection of such moments in macroscopic pieces of matter are proposed
Weyl type N solutions with null electromagnetic fields in the Einstein-Maxwell p-form theory
Czech Academy of Sciences Publication Activity Database
Kuchynka, Martin; Pravdová, Alena
2017-01-01
Roč. 49, č. 5 (2017), č. článku 71. ISSN 0001-7701 R&D Projects: GA ČR GA13-10042S Institutional support: RVO:67985840 Keywords : Einstein –Maxwell equations * Weyl type N spacetimes * Kundt spacetimes Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 1.618, year: 2016 https://link.springer.com/article/10.1007/s10714-017-2234-7
Geometric properties of static Einstein-Maxwell dilaton horizons with a Liouville potential
International Nuclear Information System (INIS)
Abdolrahimi, Shohreh; Shoom, Andrey A.
2011-01-01
We study nondegenerate and degenerate (extremal) Killing horizons of arbitrary geometry and topology within the Einstein-Maxwell-dilaton model with a Liouville potential (the EMdL model) in d-dimensional (d≥4) static space-times. Using Israel's description of a static space-time, we construct the EMdL equations and the space-time curvature invariants: the Ricci scalar, the square of the Ricci tensor, and the Kretschmann scalar. Assuming that space-time metric functions and the model fields are real analytic functions in the vicinity of a space-time horizon, we study the behavior of the space-time metric and the fields near the horizon and derive relations between the space-time curvature invariants calculated on the horizon and geometric invariants of the horizon surface. The derived relations generalize similar relations known for horizons of static four- and five-dimensional vacuum and four-dimensional electrovacuum space-times. Our analysis shows that all the extremal horizon surfaces are Einstein spaces. We present the necessary conditions for the existence of static extremal horizons within the EMdL model.
Maxwell+TDDFT multiscale method for light propagation in thin-film semiconductor
Uemoto, Mitsuharu; Yabana, Kazuhiro
First-principles time-dependent density functional theory (TDDFT) has been a powerful tool to describe light-matter interactions and widely used to describe electronic excitations and linear and nonlinear optical properties of molecules and solids. We have been developing a novel multiscale modeling to describe a propagation of light pulse in a macroscopic medium combining TDDFT and Maxwell equations. In the method, the finite-difference time-domain (FDTD)-like electromagnetism (EM) calculation is carried out in a macroscopic grid. At each grid point, the time-dependent Kohn-Sham equation is solved in real time. In the presentation, we show applications of this method to the 1D/2D propagations of femtosecond laser pulses through a thin-film semiconductor. This work was supported in part by MEXT as a social and scientific priority issue (Creation of new functional devices and high-performance materials to support next-generation industries; CDMSI) to be tackled by using post-K computer.
Nanoscale roughness effect on Maxwell-like boundary conditions for the Boltzmann equation
Energy Technology Data Exchange (ETDEWEB)
Brull, S., E-mail: Stephane.Brull@math.u-bordeaux.fr; Charrier, P., E-mail: Pierre.Charrier@math.u-bordeaux.fr; Mieussens, L., E-mail: Luc.Mieussens@math.u-bordeaux.fr [University of Bordeaux, CNRS, Bordeaux INP, IMB, UMR 5251, F-33400 Talence (France)
2016-08-15
It is well known that the roughness of the wall has an effect on microscale gas flows. This effect can be shown for large Knudsen numbers by using a numerical solution of the Boltzmann equation. However, when the wall is rough at a nanometric scale, it is necessary to use a very small mesh size which is much too expansive. An alternative approach is to incorporate the roughness effect in the scattering kernel of the boundary condition, such as the Maxwell-like kernel introduced by the authors in a previous paper. Here, we explain how this boundary condition can be implemented in a discrete velocity approximation of the Boltzmann equation. Moreover, the influence of the roughness is shown by computing the structure scattering pattern of mono-energetic beams of the incident gas molecules. The effect of the angle of incidence of these molecules, of their mass, and of the morphology of the wall is investigated and discussed in a simplified two-dimensional configuration. The effect of the azimuthal angle of the incident beams is shown for a three-dimensional configuration. Finally, the case of non-elastic scattering is considered. All these results suggest that our approach is a promising way to incorporate enough physics of gas-surface interaction, at a reasonable computing cost, to improve kinetic simulations of micro- and nano-flows.
On Some Unusual Properties of Wave Solutions of Free Maxwell Equations
Directory of Open Access Journals (Sweden)
Augusto Espinoza
2006-01-01
Full Text Available Se descubren algunas propiedades inusuales de las soluciones de las llamadas ecuaciones libres de Maxwell. Mostramos la existencia de soluciones que representan las ondas electromagnéticas en el vacío para los cuales el vector de Poynting no coincide con el vector de Umov. Se presentan soluciones que corresponden a ondas magnéticas estacionarias de una configuración inusual en el vacío, que describen en el vacio formaciones estables anulares y esféricas de campo. Se demuestra que en el vacío, de acuerdo a las soluciones obtenidas el campo eléctrico E puede ser un vector polar así como un vector axial; y el campo magnético B, en su turno, puede ser un vector axial así como también un vector polar. Se muestra que tales soluciones existen cuando los vectores E y B, no son vectores polares ni axiales. Además, estas soluciones corresponden a ondas electromagnéticas que no transfieren energía ni momentos en cualquier punto del vacío.
Rogue waves of the Hirota and the Maxwell-Bloch equations
Li, Chuanzhong; He, Jingsong; Porseizan, K.
2013-01-01
In this paper, we derive a Darboux transformation of the Hirota and the Maxwell-Bloch (H-MB) system which is governed by femtosecond pulse propagation through an erbium doped fiber and further generalize it to the matrix form of the n-fold Darboux transformation of this system. This n-fold Darboux transformation implies the determinant representation of nth solutions of (E[n],p[n],η[n]) generated from the known solution of (E,p,η). The determinant representation of (E[n],p[n],η[n]) provides soliton solutions, positon solutions, and breather solutions (both bright and dark breathers) of the H-MB system. From the breather solutions, we also construct a bright and dark rogue wave solution for the H-MB system, which is currently one of the hottest topics in mathematics and physics. Surprisingly, the rogue wave solution for p and η has two peaks because of the order of the numerator and denominator of them. Meanwhile, after fixing the time and spatial parameters and changing two other unknown parameters α and β, we generate a rogue wave shape.
HARP: a submillimetre heterodyne array receiver operating on the James Clerk Maxwell Telescope
Smith, H.; Buckle, J.; Hills, R.; Bell, G.; Richer, J.; Curtis, E.; Withington, S.; Leech, J.; Williamson, R.; Dent, W.; Hastings, P.; Redman, R.; Wooff, B.; Yeung, K.; Friberg, P.; Walther, C.; Kackley, R.; Jenness, T.; Tilanus, R.; Dempsey, J.; Kroug, M.; Zijlstra, T.; Klapwijk, T. M.
2008-07-01
This paper describes the key design features and performance of HARP, an innovative heterodyne focal-plane array receiver designed and built to operate in the submillimetre on the James Clerk Maxwell Telescope (JCMT) in Hawaii. The 4x4 element array uses SIS detectors, and is the first sub-millimetre spectral imaging system on the JCMT. HARP provides 3-dimensional imaging capability with high sensitivity at 325-375 GHz and affords significantly improved productivity in terms of speed of mapping. HARP was designed and built as a collaborative project between the Cavendish Astrophysics Group in Cambridge UK, the UK-Astronomy Technology Centre in Edinburgh UK, the Herzberg Institute of Astrophysics in Canada and the Joint Astronomy Centre in Hawaii. SIS devices for the mixers were fabricated to a Cavendish Astrophysics Group design at the Delft University of Technology in the Netherlands. Working in conjunction with the new Auto Correlation Spectral Imaging System (ACSIS), first light with HARP was achieved in December 2005. HARP synthesizes a number of interesting features across all elements of the design; we present key performance characteristics and images of astronomical observations obtained during commissioning.
Holographic QCD phase diagram with critical point from Einstein-Maxwell-dilaton dynamics
Knaute, J.; Yaresko, R.; Kämpfer, B.
2018-03-01
Supplementing the holographic Einstein-Maxwell-dilaton model of [1,2] by input of lattice QCD data for 2 + 1 flavors and physical quark masses for the equation of state and quark number susceptibility at zero baryo-chemical potential we explore the resulting phase diagram over the temperature-chemical potential plane. A first-order phase transition sets in at a temperature of about 112 MeV and a baryo-chemical potential of 612 MeV. We estimate the accuracy of the critical point position in the order of approximately 5-8% by considering parameter variations and different low-temperature asymptotics for the second-order quark number susceptibility. The critical pressure as a function of the temperature has a positive slope, i.e. the entropy per baryon jumps up when crossing the phase border line from larger values of temperature/baryo-chemical potential, thus classifying the phase transition as a gas-liquid one. The updated holographic model exhibits in- and outgoing isentropes in the vicinity of the first-order phase transition.
Energy Technology Data Exchange (ETDEWEB)
DAY,DAVID M.; NEWMAN,GREGORY A.
1999-10-01
A fast precondition technique has been developed which accelerates the finite difference solutions of the 3D Maxwell's equations for geophysical modeling. The technique splits the electric field into its curl free and divergence free projections, and allows for the construction of an inverse operator. Test examples show an order of magnitude speed up compared with a simple Jacobi preconditioner. Using this preconditioner a low frequency Neumann series expansion is developed and used to compute responses at multiple frequencies very efficiently. Simulations requiring responses at multiple frequencies, show that the Neumann series is faster than the preconditioned solution, which must compute solutions at each discrete frequency. A Neumann series expansion has also been developed in the high frequency limit along with spectral Lanczos methods in both the high and low frequency cases for simulating multiple frequency responses with maximum efficiency. The research described in this report was to have been carried out over a two-year period. Because of communication difficulties, the project was funded for first year only. Thus the contents of this report are incomplete with respect to the original project objectives.
Asymptotic structure of the Einstein-Maxwell theory on AdS3
Pérez, Alfredo; Riquelme, Miguel; Tempo, David; Troncoso, Ricardo
2016-02-01
The asymptotic structure of AdS spacetimes in the context of General Relativity coupled to the Maxwell field in three spacetime dimensions is analyzed. Although the fall-off of the fields is relaxed with respect to that of Brown and Henneaux, the variation of the canonical generators associated to the asymptotic Killing vectors can be shown to be finite once required to span the Lie derivative of the fields. The corresponding surface integrals then acquire explicit contributions from the electromagnetic field, and become well-defined provided they fulfill suitable integrability conditions, implying that the leading terms of the asymptotic form of the electromagnetic field are functionally related. Consequently, for a generic choice of boundary conditions, the asymptotic symmetries are broken down to {R}⊗ U(1)⊗ U(1) . Nonetheless, requiring compatibility of the boundary conditions with one of the asymptotic Virasoro symmetries, singles out the set to be characterized by an arbitrary function of a single variable, whose precise form depends on the choice of the chiral copy. Remarkably, requiring the asymptotic symmetries to contain the full conformal group selects a very special set of boundary conditions that is labeled by a unique constant parameter, so that the algebra of the canonical generators is given by the direct sum of two copies of the Virasoro algebra with the standard central extension and U (1). This special set of boundary conditions makes the energy spectrum of electrically charged rotating black holes to be well-behaved.
Consistent S2 Pauli reduction of six-dimensional chiral gauged Einstein-Maxwell supergravity
Gibbons, G. W.; Pope, C. N.
2004-10-01
Six-dimensional N=(1,0) Einstein-Maxwell gauged supergravity is known to admit a (Minkowski) 4× S2 vacuum solution with four-dimensional N=1 chiral supersymmetry. The massless sector comprises a supergravity multiplet, an SU(2) Yang-Mills vector multiplet, and a scalar multiplet. In this paper it is shown that, remarkably, the six-dimensional theory admits a fully consistent dimensional reduction on the 2-sphere, implying that all solutions of the four-dimensional N=1 supergravity can be lifted back to solutions in six dimensions. This provides a striking realisation of the idea, first proposed by Pauli, of obtaining a theory that includes Yang-Mills fields by dimensional reduction on a coset space. We address the cosmological constant problem within this model, and argue that, contrary to recent suggestions, fine-tuning is still required. We also suggest a link between a modification of the model with 3-branes, and a five-dimensional model based on an S/Z orbifold.
Maxwell-Wagner polarization and frequency-dependent injection at aqueous electrical interfaces.
Desmond, Mitchell; Mavrogiannis, Nicholas; Gagnon, Zachary
2012-11-02
We demonstrate a new type of alternating current (ac) interfacial polarization and frequency-dependent fluid displacement phenomenon at a liquid-liquid electrical interface. Two fluid streams--one with a greater electrical conductivity and the other a greater dielectric constant--are made to flow side by side in a microfluidic channel. An ac electric field is applied perpendicular to the interface formed between the liquid lamellae, and fluid is observed to displace across the liquid-liquid interface. The direction and magnitude of this displacement is frequency dependent. At low ac frequency, below the interfacial inverse charge relaxation time, the high-conductivity fluid displaces into the high-dielectric stream. At high frequency the direction of liquid displacement reverses, and the high-dielectric stream injects into the high-conductivity stream. The interfacial crossover frequency where the liquid displacement direction reverses is dependent on differences in electrical properties between the two fluid streams, and is well explained by Maxwell-Wagner polarization mechanics.
Algorithmic information content, Church-Turing thesis, physical entropy, and Maxwell's Demon
International Nuclear Information System (INIS)
Zurek, W.H.
1990-01-01
Measurement converts alternative possibilities of its potential outcomes into the definiteness of the record--data describing the actual outcome. The resulting decrease of statistical entropy has been, since the inception of the Maxwell's Demon, regarded as a threat to the second law of thermodynamics. For, when the statistical entropy is employed as the measure of the useful work which can be extracted from the system its decrease by the information gathering actions of the observer would lead one to believe that, at least from the observers viewpoint, the second law can be violated. The author shows that the decrease of ignorance does not necessarily lead to the lowering of disorder of the measured physical system. Measurements can only convert uncertainty (quantified by the statistical entropy) into randomness of the outcome (given by the algorithmic information content of the data). The ability to extract useful work is measured by physical entropy, which is equal to the sum of these two measures of disorder. So defined physical entropy is, on the average, constant in course of the measurements carried out by the observer on an equilibrium system. 27 refs., 5 figs
Characterizing the performance of the Conway-Maxwell Poisson generalized linear model.
Francis, Royce A; Geedipally, Srinivas Reddy; Guikema, Seth D; Dhavala, Soma Sekhar; Lord, Dominique; LaRocca, Sarah
2012-01-01
Count data are pervasive in many areas of risk analysis; deaths, adverse health outcomes, infrastructure system failures, and traffic accidents are all recorded as count events, for example. Risk analysts often wish to estimate the probability distribution for the number of discrete events as part of doing a risk assessment. Traditional count data regression models of the type often used in risk assessment for this problem suffer from limitations due to the assumed variance structure. A more flexible model based on the Conway-Maxwell Poisson (COM-Poisson) distribution was recently proposed, a model that has the potential to overcome the limitations of the traditional model. However, the statistical performance of this new model has not yet been fully characterized. This article assesses the performance of a maximum likelihood estimation method for fitting the COM-Poisson generalized linear model (GLM). The objectives of this article are to (1) characterize the parameter estimation accuracy of the MLE implementation of the COM-Poisson GLM, and (2) estimate the prediction accuracy of the COM-Poisson GLM using simulated data sets. The results of the study indicate that the COM-Poisson GLM is flexible enough to model under-, equi-, and overdispersed data sets with different sample mean values. The results also show that the COM-Poisson GLM yields accurate parameter estimates. The COM-Poisson GLM provides a promising and flexible approach for performing count data regression. © 2011 Society for Risk Analysis.
Brownian motion surviving in the unstable cubic potential and the role of Maxwell's demon
Ornigotti, Luca; Ryabov, Artem; Holubec, Viktor; Filip, Radim
2018-03-01
The trajectories of an overdamped particle in a highly unstable potential diverge so rapidly, that the variance of position grows much faster than its mean. A description of the dynamics by moments is therefore not informative. Instead, we propose and analyze local directly measurable characteristics, which overcome this limitation. We discuss the most probable particle position (position of the maximum of the probability density) and the local uncertainty in an unstable cubic potential, V (x ) ˜x3 , both in the transient regime and in the long-time limit. The maximum shifts against the acting force as a function of time and temperature. Simultaneously, the local uncertainty does not increase faster than the observable shift. In the long-time limit, the probability density naturally attains a quasistationary form. We interpret this process as a stabilization via the measurement-feedback mechanism, the Maxwell demon, which works as an entropy pump. The rules for measurement and feedback naturally arise from the basic properties of the unstable dynamics. All reported effects are inherent in any unstable system. Their detailed understanding will stimulate the development of stochastic engines and amplifiers and, later, their quantum counterparts.
Eaters of the lotus: Landauer's principle and the return of Maxwell's demon
Norton, John D.
Landauer's principle is the loosely formulated notion that the erasure of n bits of information must always incur a cost of k ln n in thermodynamic entropy. It can be formulated as a precise result in statistical mechanics, but for a restricted class of erasure processes that use a thermodynamically irreversible phase space expansion, which is the real origin of the law's entropy cost and whose necessity has not been demonstrated. General arguments that purport to establish the unconditional validity of the law (erasure maps many physical states to one; erasure compresses the phase space) fail. They turn out to depend on the illicit formation of a canonical ensemble from memory devices holding random data. To exorcise Maxwell's demon one must show that all candidate devices-the ordinary and the extraordinary-must fail to reverse the second law of thermodynamics. The theorizing surrounding Landauer's principle is too fragile and too tied to a few specific examples to support such general exorcism. Charles Bennett's recent extension of Landauer's principle to the merging of computational paths fails for the same reasons as trouble the original principle.
Discrete Boltzmann Method with Maxwell-Type Boundary Condition for Slip Flow
Zhang, Yu-Dong; Xu, Ai-Guo; Zhang, Guang-Cai; Chen, Zhi-Hua
2018-01-01
The rarefied effect of gas flow in microchannel is significant and cannot be well described by traditional hydrodynamic models. It has been known that discrete Boltzmann model (DBM) has the potential to investigate flows in a relatively wider range of Knudsen number because of its intrinsic kinetic nature inherited from Boltzmann equation. It is crucial to have a proper kinetic boundary condition for DBM to capture the velocity slip and the flow characteristics in the Knudsen layer. In this paper, we present a DBM combined with Maxwell-type boundary condition model for slip flow. The tangential momentum accommodation coefficient is introduced to implement a gas-surface interaction model. Both the velocity slip and the Knudsen layer under various Knudsen numbers and accommodation coefficients can be well described. Two kinds of slip flows, including Couette flow and Poiseuille flow, are simulated to verify the model. To dynamically compare results from different models, the relation between the definition of Knudsen number in hard sphere model and that in BGK model is clarified. Support of National Natural Science Foundation of China under Grant Nos. 11475028, 11772064, and 11502117 Science Challenge Project under Grant Nos. JCKY2016212A501 and TZ2016002
Chai, Jun; Tian, Bo; Sun, Wen-Rong; Liu, De-Yin
2018-01-01
Under investigation in this paper is the reduced Maxwell-Bloch equations with variable coefficients, which describe the propagation of the intense ultra-short optical pulses through an inhomogeneous two-level dielectric medium. Hirota method and symbolic computation are applied to solve such equations. By introducing the dependent variable transformations, we give the bilinear forms, vector one-, two- and N-soliton solutions in analytic forms. The types of the vector solitons are analyzed: Only the bright-single-hump solitons can be observed in q and r1 , the soliton in r2 is the bright-double-hump soliton, and there exist three types of solitons in r3 , including the dark-single-hump soliton, dark-double-hump soliton and dark-like-bright soliton, with q as the inhomogeneous electric field, r1 and r2 as the real and imaginary parts of the polarization of the two-level medium, and r3 as the population difference between the ground and excited states. Figures are presented to show the vector soliton solutions. Different types of the interactions between the vector two solitons are presented. In each component, only the overtaking elastic interaction can be observed.
Mujal, Eudald; Fortuny, Josep; Pérez-Cano, Jordi; Dinarès-Turell, Jaume; Ibáñez-Insa, Jordi; Oms, Oriol; Vila, Isabel; Bolet, Arnau; Anadón, Pere
2017-12-01
The most severe biotic crisis on Earth history occurred during the Permian-Triassic (PT) transition around 252 Ma. Whereas in the marine realm such extinction event is well-constrained, in terrestrial settings it is still poorly known, mainly due to the lack of suitable complete sections. This is utterly the case along the Western Tethys region, located at Pangaea's equator, where terrestrial successions are typically build-up of red beds often characterised by a significant erosive gap at the base of the Triassic strata. Henceforth, documenting potentially complete terrestrial successions along the PT transition becomes fundamental. Here, we document the exceptional Coll de Terrers area from the Catalan Pyrenees (NE Iberian Peninsula), for which a multidisciplinary research is conducted along the PT transition. The red-bed succession, located in a long E-W extended narrow rift system known as Pyrenean Basin, resulted from a continuous sedimentary deposition evolving from meandering (lower Upper Red Unit) to playa-lake/ephemeral lacustrine (upper Upper Red Unit) and again to meandering settings (Buntsandstein facies). Sedimentary continuity is suggested by preliminary cyclostratigraphic analysis that warrants further analysis. Our combined sedimentological, mineralogical and geochemical data infer a humid-semiarid-humid climatic trend across the studied succession. The uppermost Permian strata, deposited under an orbitally controlled monsoonal regime, yields a relatively diverse ichnoassemblage mainly composed of tetrapod footprints and arthropod trace fossils. Such fossils indicate appropriate life conditions and water presence in levels that also display desiccation structures. These levels alternate with barren intervals formed under dry conditions, being thus indicative of strong seasonality. All these features are correlated with those reported elsewhere in Gondwana and Laurasia, and suggest that the Permian-Triassic boundary might be recorded somewhere around
Bai, Yu; Jiang, Yuehua; Liu, Fawang; Zhang, Yan
2017-12-01
This paper investigates the incompressible fractional MHD Maxwell fluid due to a power function accelerating plate with the first order slip, and the numerical analysis on the flow and heat transfer of fractional Maxwell fluid has been done. Moreover the deformation motion of fluid micelle is simply analyzed. Nonlinear velocity equation are formulated with multi-term time fractional derivatives in the boundary layer governing equations, and convective heat transfer boundary condition and viscous dissipation are both taken into consideration. A newly finite difference scheme with L1-algorithm of governing equations are constructed, whose convergence is confirmed by the comparison with analytical solution. Numerical solutions for velocity and temperature show the effects of pertinent parameters on flow and heat transfer of fractional Maxwell fluid. It reveals that the fractional derivative weakens the effects of motion and heat conduction. The larger the Nusselt number is, the greater the heat transfer capacity of fluid becomes, and the temperature gradient at the wall becomes more significantly. The lower Reynolds number enhances the viscosity of the fluid because it is the ratio of the viscous force and the inertia force, which resists the flow and heat transfer.
Directory of Open Access Journals (Sweden)
Yu Bai
2017-12-01
Full Text Available This paper investigates the incompressible fractional MHD Maxwell fluid due to a power function accelerating plate with the first order slip, and the numerical analysis on the flow and heat transfer of fractional Maxwell fluid has been done. Moreover the deformation motion of fluid micelle is simply analyzed. Nonlinear velocity equation are formulated with multi-term time fractional derivatives in the boundary layer governing equations, and convective heat transfer boundary condition and viscous dissipation are both taken into consideration. A newly finite difference scheme with L1-algorithm of governing equations are constructed, whose convergence is confirmed by the comparison with analytical solution. Numerical solutions for velocity and temperature show the effects of pertinent parameters on flow and heat transfer of fractional Maxwell fluid. It reveals that the fractional derivative weakens the effects of motion and heat conduction. The larger the Nusselt number is, the greater the heat transfer capacity of fluid becomes, and the temperature gradient at the wall becomes more significantly. The lower Reynolds number enhances the viscosity of the fluid because it is the ratio of the viscous force and the inertia force, which resists the flow and heat transfer.
Research staff and public engagement
DEFF Research Database (Denmark)
Davies, Sarah Rachael
2013-01-01
Public engagement plays an important role in the contemporary UK academy, and is promoted through initiatives such as Beacons of Public Engagement and research grant 'Pathways to Impact'. Relatively little is known, however, about academic experiences of such engagement activities. This study...... focuses on one staff group, contract researchers, to explore the perceived challenges and opportunities of public engagement. Qualitative and quantitative data-from a web-based survey and three focus groups-are used to show that, while engagement activities are often seen as rewarding, the challenges...... involved in participating in them are profound. While researchers report practical needs, such as for logistical support or communication training, key barriers relate to the conditions of contract research more generally, and specifically to job insecurity, transiency, and lack of autonomy....
The operational staff during exercise RESUME-95
Energy Technology Data Exchange (ETDEWEB)
Jensen, J. [Jensen Consult, Virum (Denmark)
1997-12-31
With more than 100 participants entering the exercise RESUME-95 the Exercise Planning Committee decided to establish an operational staff named Directing Staff (DISTAFF) to ensure that the exercise plan was followed, the planned activities were carried out and to intervene if anything went wrong. In general the duties of the operational staff involve tasks such as secretarial assistance, keeping log of the progress of the situation and gathering, updating and distributing information on all aspects of the situation. Throughout the entire event it is the staff`s responsibility to keep a general view of the current situation and to make the necessary plans for the progress of the situation based on the available information. Furthermore the staff should ensure necessary contact to the public and to the media. (au).
Measuring hospital medical staff organizational structure.
Shortell, S M; Getzen, T E
1979-01-01
Based on organization theory and the work of Roemer and Friedman, seven dimensions of hospital medical staff organization structure are proposed and examined. The data are based on a 1973 nationwide survey of hospital medical staffs conducted by the American Hospital Association. Factor analysis yielded six relatively independent dimensions supporting a multidimensional view of medical staff organization structure. The six dimensions include 1) Resource Capability, 2) Generalist Physician Contractual Orientation, 3) Communication/Control, 4) Local Staff Orientation, 5) Participation in Decision Making, and 6) Hospital-Based Physician Contractual Orientation. It is suggested that these dimensions can be used to develop an empirical typology of hospital medical staff organization structure and to investigate the relationship between medical staff organization and public policy issues related to cost containment and quality assurance. PMID:511580
Job Satisfaction Of Hospital Nursing Staff
Charlotte Pietersen
2005-01-01
Health care managers realize that job satisfaction impacts on nursing staff retention. This study examined the job satisfaction of nursing staff (N = 109) at a government hospital. Just more than half of the respondents were generally satisfied. Feelings that nursing is worthwhile and satisfying, and financial stability at the hospital could promote staff retention. Specific intrinsic - (promotion), and extrinsic factors (routinization, working conditions, pay, interaction with supervisors, a...
The staff regulations of the Agency
International Nuclear Information System (INIS)
2002-01-01
Following the first comprehensive review of the Provisional Staff Regulations conducted by the Secretariat, the Board of Governors approved on 12 June 2002 amendments to the Provisional Staff Regulations including the removal of the attribute 'provisional' from their title. The revised Staff Regulations of the Agency are set forth in this document for the information of all Members of the Agency. There is a subject index at the end of the document
The relationship between empowerment and effectiveness of staff ...
African Journals Online (AJOL)
Effectiveness is one of the management concepts considered and studied always by management scientists and experts. The aim of this study was to investigate the effects of different dimensions of empowerment (servicing staff, staff monitoring, consulting staff, and training staff) on dimensions of effectiveness of staff (staff ...
Amendments to the Staff Rules and Regulations
2003-01-01
The Staff Rules and Regulations in force since 1 January 1996 are modified as follows: as from 1 April 2003 Article R II 1.19 - Types and duration of contracts of staff members (page 15) as from 1 July 2003 Implementation of the category of local staff members Copies of this update are available in the divisional secretariats. In addition, Staff Rules and Regulations are available for consultation on the Web at http://cern.ch/hr-div/internal/admin_services/rules/default.asp Human Resources Division Tel. 74128
Job Satisfaction Of Hospital Nursing Staff
Directory of Open Access Journals (Sweden)
Charlotte Pietersen
2005-11-01
Full Text Available Health care managers realize that job satisfaction impacts on nursing staff retention. This study examined the job satisfaction of nursing staff (N = 109 at a government hospital. Just more than half of the respondents were generally satisfied. Feelings that nursing is worthwhile and satisfying, and financial stability at the hospital could promote staff retention. Specific intrinsic - (promotion, and extrinsic factors (routinization, working conditions, pay, interaction with supervisors, and organizational support could impact negatively on retention. Management should use these findings as a basis for staff consultation, developmental strategies, and interventions. Future research on other nursing populations is recommended.
Collimated thermal radiation transfer via half Maxwell's fish-eye lens for thermophotovoltaics
Chung, Haejun; Zhou, Zhiguang; Bermel, Peter
2017-05-01
Thermophotovoltaics (TPV) convert heat into electricity by capturing thermal radiation with a photovoltaic (PV) cell, ideally at efficiencies of 50% or more. However, excess heating of the PV cell from close proximity to the emitter substantially reduces the system efficiency. In this work, we theoretically develop and numerically demonstrate an approach to fundamentally improving TPV systems that allow for a much greater separation of an emitter and a receiver. Thus, we solve the excess heating dilemma, required for achieving theoretically high efficiencies. It consists of a spherically graded index lens known as Maxwell's Fish-Eye (MFE) structure, capable of collimating hemispherical emission into a much narrower range of angles, close to the normal direction. To fully characterize the power radiation profile of the MFE, we perform finite-difference time-domain simulations for a quarter MFE and then map it onto a Gaussian beam approximation. The modeled beam properties are subsequently used to study a half MFE. In an optimized half MFE design, 90% of all thermal photons reach a receiver at a distance of 100 λ; by comparison, only 15.6% of a blackbody emitter reach a receiver in the same geometry. It is also shown that the emission achieved by a half MFE can lead to a photon recycling rate above 95% for below bandgap photons at an emitter-receiver separation of 100 λ. By applying a half MFE, the absolute TPV efficiency can be improved from 5.74% to 37.15%, which represents a significant step forward in realizing high-efficiency TPV systems.
High-order FDTD methods via derivative matching for Maxwell's equations with material interfaces
International Nuclear Information System (INIS)
Zhao Shan; Wei, G.W.
2004-01-01
This paper introduces a series of novel hierarchical implicit derivative matching methods to restore the accuracy of high-order finite-difference time-domain (FDTD) schemes of computational electromagnetics (CEM) with material interfaces in one (1D) and two spatial dimensions (2D). By making use of fictitious points, systematic approaches are proposed to locally enforce the physical jump conditions at material interfaces in a preprocessing stage, to arbitrarily high orders of accuracy in principle. While often limited by numerical instability, orders up to 16 and 12 are achieved, respectively, in 1D and 2D. Detailed stability analyses are presented for the present approach to examine the upper limit in constructing embedded FDTD methods. As natural generalizations of the high-order FDTD schemes, the proposed derivative matching methods automatically reduce to the standard FDTD schemes when the material interfaces are absent. An interesting feature of the present approach is that it encompasses a variety of schemes of different orders in a single code. Another feature of the present approach is that it can be robustly implemented with other high accuracy time-domain approaches, such as the multiresolution time-domain method and the local spectral time-domain method, to cope with material interfaces. Numerical experiments on both 1D and 2D problems are carried out to test the convergence, examine the stability, access the efficiency, and explore the limitation of the proposed methods. It is found that operating at their best capacity, the proposed high-order schemes could be over 2000 times more efficient than their fourth-order versions in 2D. In conclusion, the present work indicates that the proposed hierarchical derivative matching methods might lead to practical high-order schemes for numerical solution of time-domain Maxwell's equations with material interfaces
A Full-Maxwell Approach for Large-Angle Polar Wander of Viscoelastic Bodies
Hu, H.; van der Wal, W.; Vermeersen, L. L. A.
2017-12-01
For large-angle long-term true polar wander (TPW) there are currently two types of nonlinear methods which give approximated solutions: those assuming that the rotational axis coincides with the axis of maximum moment of inertia (MoI), which simplifies the Liouville equation, and those based on the quasi-fluid approximation, which approximates the Love number. Recent studies show that both can have a significant bias for certain models. Therefore, we still lack an (semi)analytical method which can give exact solutions for large-angle TPW for a model based on Maxwell rheology. This paper provides a method which analytically solves the MoI equation and adopts an extended iterative procedure introduced in Hu et al. (2017) to obtain a time-dependent solution. The new method can be used to simulate the effect of a remnant bulge or models in different hydrostatic states. We show the effect of the viscosity of the lithosphere on long-term, large-angle TPW. We also simulate models without hydrostatic equilibrium and show that the choice of the initial stress-free shape for the elastic (or highly viscous) lithosphere of a given model is as important as its thickness for obtaining a correct TPW behavior. The initial shape of the lithosphere can be an alternative explanation to mantle convection for the difference between the observed and model predicted flattening. Finally, it is concluded that based on the quasi-fluid approximation, TPW speed on Earth and Mars is underestimated, while the speed of the rotational axis approaching the end position on Venus is overestimated.
Staff Group Trainer: Development of a Computer-Driven, Structured, Staff Training Environment
National Research Council Canada - National Science Library
Koger, Milton
1998-01-01
.... The project produced two training support packages (TSP)--battalion and brigade--designed to train these staffs to more effectively and efficiently communicate within and between staff sections, command post, and the unit commander...
An Epidemiological Approach to Staff Burnout.
Kamis, Edna
This paper describes a conceptual model of staff burnout in terms of independent, intervening and dependent variables. Staff burnout is defined, symptoms are presented, and the epidemiological approach to burnout is descussed. Components of the proposed model, which groups determinants of mental health into three domains, consist of: (1)…
Training Staff to Manage Challenging Behaviour
van Oorsouw, Wietske M. W. J.; Embregts, Petri J. C. M.; Bosman, Anna M. T.; Jahoda, Andrew
2010-01-01
Background: A training package for staff working with clients presenting challenging behaviour was developed to (1) increase their knowledge regarding challenging behaviour, and (2) to improve the quality of physical intervention techniques. The latter aim was intended to reduce staff anxiety about dealing with incidents and limit physical risk of…
20 CFR 638.801 - Staff training.
2010-04-01
... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Staff training. 638.801 Section 638.801 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR JOB CORPS PROGRAM UNDER TITLE IV-B OF THE JOB TRAINING PARTNERSHIP ACT Administrative Provisions § 638.801 Staff training. The...
The Support Needs of Staff Developers.
Nicol, David J.
1992-01-01
Describes a study conducted at an annual staff development conference to determine the needs of professional staff developers in British higher education. An overview of the research strategy, which was based on an action research model, is provided; the ranking of needs areas is discussed; and needs statements with justifications are appended.…
Gaming: a creative strategy for staff education.
Swartzendruber, D
1994-02-01
Providing staff development in a stimulating, innovative manner is the challenge of all nurse educators. This article discusses gaming, a creative teaching strategy that can help meet these needs. Games designed specifically for the education of dialysis staff will be reviewed. Advantages of the various games will also be examined.
Futuristics: A Tool for Staff Training.
Barr, Margaret J.; Hurst, James C.
1979-01-01
Creative use of future planning as a staff development tool can have short- and long-term benefits for the individual and the organization. Its potential for stimulating creativity, reducing crisis management, and developing staff cohesion is unequaled. The individual, the organization, the technology and the manager are the important factors.…
2010-07-01
... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Staff Offices. 1.25 Section 1.25 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY GENERAL STATEMENT OF ORGANIZATION AND GENERAL INFORMATION Headquarters § 1.25 Staff Offices. (a) Office of Administrative Law Judges. The Office of...
Training Staff to Manage Challenging Behaviour
Oorsouw, W.M.W.J. van; Embregts, P.J.C.M.; Bosman, A.M.T.; Jahoda, A.
2010-01-01
Background - A training package for staff working with clients presenting challenging behaviour was developed to (1) increase their knowledge regarding challenging behaviour, and (2) to improve the quality of physical intervention techniques. The latter aim was intended to reduce staff anxiety about
An Ivory Staff Terminal from Alcester
Directory of Open Access Journals (Sweden)
Sandy Heslop
2017-06-01
Full Text Available The Alcester staff terminal is an outstanding example of late Anglo-Saxon carving on a small scale. It was supposedly discovered in 1873 in the garden of the rectory at Alcester (Warwickshire and comes from a pastoral staff that would have belonged to a bishop or abbot. This article contains a 3D visualisation of the terminal.
Quality Control in Child Care Staff Selection
Crow, Merwin R.
1975-01-01
This paper focuses on the process of staff selection of child care staff at a residential treatment center for children, ages 8-16. Phases of candidate selection, an "open-door" interview procedure, the orientation of hired candidates and the agency's philosophy, procedures and practices are discussed. (GO)
Staff attitudes towards patients with schizophrenia
DEFF Research Database (Denmark)
Vendsborg, Per; Bratbo, Johanne; Dannevang, Anders
2013-01-01
Stigmatizing attitudes have been reported in international studies among staff in psychiatry. The authors wanted to investigate if this was the case in Denmark.......Stigmatizing attitudes have been reported in international studies among staff in psychiatry. The authors wanted to investigate if this was the case in Denmark....
29 CFR 511.7 - Committee staff.
2010-07-01
... 29 Labor 3 2010-07-01 2010-07-01 false Committee staff. 511.7 Section 511.7 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS WAGE ORDER PROCEDURE FOR AMERICAN SAMOA § 511.7 Committee staff. Each industry committee will be furnished a lawyer, to...
2010-07-01
... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Staff. 600.5 Section 600.5 Judicial Administration OFFICES OF INDEPENDENT COUNSEL, DEPARTMENT OF JUSTICE GENERAL POWERS OF SPECIAL COUNSEL § 600.5 Staff. A Special Counsel may request the assignment of appropriate Department employees to assist the...
Staff/bed and staff/patient ratios in South African public sector mental ...
African Journals Online (AJOL)
Objectives. To document staff/bed and staff/patient ratios in public. sector mental health services in South Africa. Design. Cross-sectional survey. Method. Aquestionnaire was distributed to provincial mental health co-ordinators requesting numbers of full-time equivalent (FTE) staff who provide mental health care at all ...
The operational staff during exercise RESUME-95
International Nuclear Information System (INIS)
Jensen, J.
1997-01-01
With more than 100 participants entering the exercise RESUME-95 the Exercise Planning Committee decided to establish an operational staff named Directing Staff (DISTAFF) to ensure that the exercise plan was followed, the planned activities were carried out and to intervene if anything went wrong. In general the duties of the operational staff involve tasks such as secretarial assistance, keeping log of the progress of the situation and gathering, updating and distributing information on all aspects of the situation. Throughout the entire event it is the staff's responsibility to keep a general view of the current situation and to make the necessary plans for the progress of the situation based on the available information. Furthermore the staff should ensure necessary contact to the public and to the media. (au)
[Burnout syndrome among health staff].
Curiel-García, José Angel; Rodríguez-Morán, Martha; Guerrero-Romero, Fernando
2006-01-01
To determine the prevalence of burnout syndrome components among the medical and nursing staff of the second care level hospitals of the Instituto Mexicano del Seguro Social and Instituto de Seguridad Social al Servicio de los Trabajadores del Estado from Durango, Mexico. A cross-sectional comparative study was carried out among 73 physicians and 100 nurses randomly selected from both hospitals. The prevalence of burnout syndrome components was established by the Maslash Burnout Inventory, which determines the presence of physical/emotional exhaustion, depersonalization, and labor performance. In addition, sociodemographic and labor information was collected. Prevalence was calculated with a reliability interval of 95% (CI 95%). 73 physicians and 100 nurses enrolled, corresponding to 22.8% and 14.5% of such personnel working in both institutions. Among the IMSS and ISSSTE workers respectively, the prevalence of depersonalization was 43.2% (34.4-52.9) and 14.5% (6.8-25.8), whereas the prevalence of physical/emotional exhaustion was 41.4% (32.7-51.1) and 19.4% (10.4-31.4). Pre-valence of labor performance was higher among the personnel of Instituto Mexicano del Seguro Social: 99.1% (95.1-100) versus 96.8% (88.8-100). Severe depersonalization (p = 0.004), but not emotional exhaustion (p = 0.09) nor labor performance (p = 0.06) was significantly higher among personnel working at the Instituto Mexicano del Seguro Social. Prevalence of depersonalization and physical/emotional exhaustion was higher among physicians and nurses of the Instituto Mexicano del Seguro Social; nonetheless, their labor performance was high. Our finding suggests that personnel working at the Instituto Mexicano del Seguro Social make a greater effort to maintain the high labor performance that medical care requires.
Training and Practices of Cannabis Dispensary Staff.
Haug, Nancy A; Kieschnick, Dustin; Sottile, James E; Babson, Kimberly A; Vandrey, Ryan; Bonn-Miller, Marcel O
2016-01-01
Introduction: The proliferation of cannabis dispensaries within the United States has emerged from patient demand for the legalization of cannabis as an alternative treatment for a number of conditions and symptoms. Unfortunately, nothing is known about the practices of dispensary staff with respect to recommendation of cannabis strains/concentrations for specific patient ailments. To address this limitation, the present study assessed the training and practices of cannabis dispensary staff. Materials and Methods: Medical and nonmedical dispensary staff ( n =55) were recruited via e-mail and social media to complete an online survey assessing their demographic characteristics, dispensary features, patient characteristics, formal training, and cannabis recommendation practices. Results: Fifty-five percent of dispensary staff reported some formal training for their position, with 20% reporting medical/scientific training. A majority (94%) indicated that they provide specific cannabis advice to patients. In terms of strains, dispensary staff trended toward recommendations of Indica for anxiety, chronic pain, insomnia, nightmares, and Tourette's syndrome. They were more likely to recommend Indica and hybrid plants for post-traumatic stress disorder (PTSD)/trauma and muscle spasms. In contrast, staff were less likely to recommend Indica for depression; hybrid strains were most often recommended for amyotrophic lateral sclerosis (ALS). In terms of cannabinoid concentrations, dispensary staff were most likely to recommend a 1:1 ratio of delta-9-tetrahydrocannabinol (THC):cannabidiol (CBD) for patients suffering from anxiety, Crohn's disease, hepatitis C, and PTSD/trauma, while patients seeking appetite stimulation were most likely to be recommended THC. Staff recommended high CBD for arthritis and Alzheimer's disease and a high CBD or 1:1 ratio for ALS, epilepsy, and muscle spasms. Conclusions: Although many dispensary staff are making recommendations consistent with
Chen, Yongpin P.; Sha, Wei E. I.; Jiang, Lijun; Meng, Min; Wu, Yu Mao; Chew, Weng Cho
2017-06-01
A novel unified Hamiltonian approach is proposed to solve Maxwell-Schrödinger equation for modeling the interaction between classical electromagnetic (EM) fields and particles. Based on the Hamiltonian of electromagnetics and quantum mechanics, a unified Maxwell-Schrödinger system is derived by the variational principle. The coupled system is well-posed and symplectic, which ensures energy conserving property during the time evolution. However, due to the disparity of wavelengths of EM waves and that of electron waves, a numerical implementation of the finite-difference time-domain (FDTD) method to the multiscale coupled system is extremely challenging. To overcome this difficulty, a reduced eigenmode expansion technique is first applied to represent the wave function of the particle. Then, a set of ordinary differential equations (ODEs) governing the time evolution of the slowly-varying expansion coefficients are derived to replace the original Schrödinger equation. Finally, Maxwell's equations represented by the vector potential with a Coulomb gauge, together with the ODEs, are solved self-consistently. For numerical examples, the interaction between EM fields and a particle is investigated for both the closed, open and inhomogeneous electromagnetic systems. The proposed approach not only captures the Rabi oscillation phenomenon in the closed cavity but also captures the effects of radiative decay and shift in the open free space. After comparing with the existing theoretical approximate models, it is found that the approximate models break down in certain cases where a rigorous self-consistent approach is needed. This work is helpful for the EM simulation of emerging nanodevices or next-generation quantum electrodynamic systems.
Energy Technology Data Exchange (ETDEWEB)
Abreu, Everton M.C. [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil); Mendes, R.; Oliveira, Wilson; Xavier, Luciana M.V. [Universidade Federal de Juiz de Fora (UFJF), MG (Brazil); Neves, Clifford [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil); Wostzasek, Clovis [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil)
2009-07-01
Full text. The interest in the dual mapping between two different theories that show the same physical properties has been increased in the last years motivated by its success in both field theory as well as string theory. At the same time, the interest in the study of theories involving higher-order derivatives is by now well appreciated and remains intense. Within the context of Maxwell theory, generalizations involving higher-order derivatives can be found in the literature. We know that in D=3+1 massive gauge fields are introduced by the Higgs Mechanism through the spontaneous breaking of symmetry. However, in the Abelian case, it is possible to introduce a massive gauge field without having to accomplish a spontaneous breaking of symmetry. So, the gauge symmetry does not forbid the appearance of the massive gauge fields. We can fall back to a topological term of mass like Chern-Simons, that in D=2+1 preserve the gauge and Lorentz symmetries. However, in D=3+1 the Lorentz symmetry is broken for the Chern-Simons theory. We find the dual equivalent (gauge invariant) version of the Maxwell theory in D=4 with a Proca-like mass term by using the symplectic embedding method. The dual theory obtained, a Maxwell-Podolsky-like theory, includes a higher-order derivative term and preserve the gauge symmetry. We also furnish an investigation of the pole structure of the vector propagator by the residue matrix which considers the eventual existence of the negative-norm of the theory. (author)
Static Einstein-Maxwell Magnetic Solitons and Black Holes in an Odd Dimensional AdS Spacetime
Blázquez-Salcedo, Jose Luis; Kunz, Jutta; Navarro-Lérida, Francisco; Radu, Eugen
2016-01-01
We construct a new class of Einstein–Maxwell static solutions with a magnetic field in D-dimensions (with D ≥ 5 an odd number), approaching at infinity a globally Anti-de Sitter (AdS) spacetime. In addition to the mass, the new solutions possess an extra-parameter associated with a non-zero magnitude of the magnetic potential at infinity. Some of the black holes possess a non-trivial zero-horizon size limit, which corresponds to a solitonic deformation of the AdS background.
International Nuclear Information System (INIS)
Montesinos, M.; Flores, E.
2006-01-01
The symmetric and gauge-invariant energy-momentum tensors for source-free Maxwell and Yang-Mills theories are obtained by means of translations in spacetime via a systematic implementation of Noether's theorem. For the source-free neutral Proca field, the same procedure yields also the symmetric energy-momentum tensor. In all cases, the key point to get the right expressions for the energy-momentum tensors is the appropriate handling of their equations of motion and the Bianchi identities. It must be stressed that these results are obtained without using Belinfante's symmetrization techniques which are usually employed to this end. (Author)
International Nuclear Information System (INIS)
Prykarpatsky, A.K.; Bogolubov, J.R.
2016-01-01
The classical Maxwell electromagnetic field and the Lorentz-type force equations are rederived in the framework of the Feynman proper time paradigm and the related vacuum field theory approach. The classical Ampere law origin is rederived, and its relationship with the Feynman proper time paradigm is discussed. The electron inertia problem is analyzed in detail within the Lagrangian and Hamiltonian formalisms and the related pressure-energy compensation principle of stochastic electrodynamics. The modified Abraham-Lorentz damping radiation force is derived and the electromagnetic electron mass origin is argued
Energy Technology Data Exchange (ETDEWEB)
Horvat, Dubravko; Ilijic, Sasa; Narancic, Zoran [Department of Physics, Faculty of Electrical Engineering and Computing, University of Zagreb, Unska 3, HR-10 000 Zagreb (Croatia)
2005-10-07
Static spherically symmetric distributions of electrically counterpoised dust (ECD) are used to construct solutions to Einstein-Maxwell equations in the Majumdar-Papapetrou formalism. Unexpected bifurcating behaviour of solutions with regard to source strength is found for localized, as well as for the delta-function ECD distributions. Unified treatment of general ECD distributions is accomplished and it is shown that for certain source strengths one class of regular solutions approaches Minkowski spacetime, while the other comes arbitrarily close to black hole solutions.
International Nuclear Information System (INIS)
Guenaydin, M.; Sierra, G.; Townsend, P.K.
1985-01-01
In this talk we give a review of our work on the construction and classification of N = 2 Maxwell-Einstein Supergravity theories (MESGT), study of the underlying algebraical and geometrical structure of these theories, and their compact and non-compact gaugings. We begin by summarizing our construction of the N = 2 MESGT's in five dimensions and give a geometrical interpretation to various scalar dependent quantities in the Lagrangian, based on the constraiants implied by supersymmetry. This is followed by a complete classification of the N = 2 MESGT's whose target manifolds parametrized by the scalar fields are symmetric spaces. 39 refs
Momentum and angular momentum in the H-space of asymptotically flat, Einstein-Maxwell space-time
International Nuclear Information System (INIS)
Hallidy, W.; Ludvigsen, M.
1979-01-01
New definitions are proposed for the momentum and angular momentum of Einstein-Maxwell fields that overcome the deficiencies of earlier definitions of these terms and are appropriate to the new H-space formulations of space-time. Definitions are made in terms of the Winicour-Tamburino linkages applied to the good cuts of Cj + . The transformations between good cuts then correspond to the translations and Lorentz transformations at points in H-space. For the special case of Robinson-Trautman type II space-times, it is shown that the definitions of momentum and angular momentum yield previously published results. (author)
Directory of Open Access Journals (Sweden)
Ronald C. Davidson
2004-02-01
Full Text Available This paper describes a self-consistent kinetic model for the longitudinal dynamics of a long, coasting beam propagating in straight (linear geometry in the z direction in the smooth-focusing approximation. Starting with the three-dimensional Vlasov-Maxwell equations, and integrating over the phase-space (x_{⊥},p_{⊥} transverse to beam propagation, a closed system of equations is obtained for the nonlinear evolution of the longitudinal distribution function F_{b}(z,p_{z},t and average axial electric field ⟨E_{z}^{s}⟩(z,t. The primary assumptions in the present analysis are that the dependence on axial momentum p_{z} of the distribution function f_{b}(x,p,t is factorable, and that the transverse beam dynamics remains relatively quiescent (absence of transverse instability or beam mismatch. The analysis is carried out correct to order k_{z}^{2}r_{w}^{2} assuming slow axial spatial variations with k_{z}^{2}r_{w}^{2}≪1, where k_{z}∼∂/∂z is the inverse length scale of axial variation in the line density λ_{b}(z,t=∫dp_{z}F_{b}(z,p_{z},t, and r_{w} is the radius of the conducting wall (assumed perfectly conducting. A closed expression for the average longitudinal electric field ⟨E_{z}^{s}⟩(z,t in terms of geometric factors, the line density λ_{b}, and its derivatives ∂λ_{b}/∂z,… is obtained for the class of bell-shaped density profiles n_{b}(r,z,t=(λ_{b}/πr_{b}^{2}f(r/r_{b}, where the shape function f(r/r_{b} has the form specified by f(r/r_{b}=(n+1(1-r^{2}/r_{b}^{2}^{n} for 0≤r
The Staff Association and its history
Staff Association
2015-01-01
The Staff Association will celebrate its 60th birthday in the spring of 2015. We are collecting all information about the sixty years of the Staff Association. In particular, we are looking at publications of the Staff Association, which started with the “Staff Association Journal”, in 1955, which later became “Le Proton déchainé”, then, more simply, “Proton” in 1982 (the figure on the left shows the different mutations of our magazine). In our collection we are missing a few issues, in particular № 1 (dated mid-1955). Dear reader, if have any old issues of this magazine, or of Graviton (figure on the right), another magazine edited by the Staff Association, or any other material or information that might help us document the history of the Staff Association, we would very much like to have a copy of the material or your contribution (written or oral). Please contact the Staff Association Sec...
Job and task analysis for technical staff
International Nuclear Information System (INIS)
Toline, B.C.
1991-01-01
In September of 1989 Cooper Nuclear Station began a project to upgrade the Technical Staff Training Program. This project's roots began by performing job and Task Analysis for Technical Staff. While the industry has long been committed to Job and Task Analysis to target performance based instruction for single job positions, this approach was unique in that it was not originally considered appropriate for a group as diverse as Tech Staff. Much to his satisfaction the Job and Task Analysis Project was much less complicated for Technical Staff than the author had imagined. The benefits of performing the Job and Task Analysis for Technical Staff have become increasingly obvious as he pursues lesson plan development and course revisions. The outline for this presentation will be as follows: philosophy adopted; preparation of the job survey document; performing the job analysis; performing task analysis for technical staff and associated pitfalls; clustering objectives for training and comparison to existing program; benefits now and in the future; final phase (comparison to INPO guides and meeting the needs of non-degreed engineering professionals); and conclusion. By focusing on performance based needs for engineers rather than traditional academics for training the author is confident the future Technical Staff Program will meet the challenges ahead and will exceed requirements for accreditation
Cooptation of Peer Support Staff: Quantitative Evidence
Directory of Open Access Journals (Sweden)
Anthony J. Alberta
2014-03-01
Full Text Available Objective In 2007, the Centers for Medicare and Medicaid Services (CMS sent a letter to state Medicaid directors outlining requirements for implementing peer-based recovery support services (P-BRSS as a Medicaid-funded service. Since then, 30 states have implemented these services. Although the literature describing implementation of P-BRSS has identified the cooptation of peer support staff (PSS as a barrier to the effective provision of P-BRSS, the evidence for it remains anecdotal. This study attempts to determine if the context of employment in either a treatment organization or peer organization affected cooptation. Methods We conducted a survey of PSS in the fall of 2013. In all, 92 of the 181 respondents were working as PSS at the time, 53 in treatment organizations. Chi-square analysis was used to determine if the context of employment had an effect on the cooptation of peer staff. Results Peer staff working in treatment organizations reported that they were supervised by treatment staff and participated in employment-related training to improve their skills at providing treatment services more frequently than their counterparts in peer organizations. Peer staff working in treatment organizations also participated in training and education to prepare for employment as treatment professionals more frequently than peer staff working in peer organizations. Conclusions and Implications for Practice Peer staff members working in treatment organizations are subject to processes of acculturation into professional cultures that peer staff working in peer organizations are not. Effective implementation of P-BRSS should include specific efforts to minimize the cooptation of peer staff.
STAFF MARKETING IN MODERN RUSSIAN CONDITIONS
Directory of Open Access Journals (Sweden)
Nataliya N. Kretova
2017-09-01
Full Text Available The conception of staff marketing, which was developed abroad, is effectively used in the developed countries for a long time. Its main advantage consists in the possibility of organizing some planning for the implementation of staff strategy: staff marketing provides the enterprise on the long-term basis with human resources capable of forming strategic potential, which would allow to implement the planned activities. Numerous problems of formation and development of civilized market relations in our country do not allow to fully implement the detailed models of staff marketing in domestic realities. On the basis of the analysis of theoretical developments and factors that have a practical impact on the implementation of marketing personnel in modern Russian conditions, the authors describe the essential elements of the conception. The primary purposes of staff marketing for domestic enterprises, grouped into the internal and external marketing are substantiated and disclosed. The special attention is paid to increasing the staff loyalty, which has dominant influence on business outcomes. The algorithm of events for the development of motivation system is proposed; at the stage of studying job satisfaction it is recommend to apply analytical calculations with the use of Shewhart control charts. Unlike traditional statistical tools based on the inspection of already implemented results, this approach is aimed at preventing negative tendencies and avoids losses associated with dissatisfaction with difficulty, as the individual employee and the team as a whole. Modern Russian enterprises can fully realize the conception of staff marketing only through rethinking of the consequences for all directions of work with the staff, as reflected in the definition of objectives, motivating staff and ensuring social responsibility of the enterprise.
14 CFR 385.33 - Review by the staff.
2010-01-01
... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Review by the staff. 385.33 Section 385.33...) ORGANIZATION STAFF ASSIGNMENTS AND REVIEW OF ACTION UNDER ASSIGNMENTS Procedure on Review of Staff Action § 385.33 Review by the staff. Where a petition for review is duly filed, the staff member may, upon...
34 CFR 75.519 - Dual compensation of staff.
2010-07-01
... 34 Education 1 2010-07-01 2010-07-01 false Dual compensation of staff. 75.519 Section 75.519... by a Grantee? Project Staff § 75.519 Dual compensation of staff. A grantee may not use its grantee to pay a project staff member for time or work for which that staff member is compensated from some other...
Directory of Open Access Journals (Sweden)
Bourel B.
2013-11-01
Full Text Available Ce papier traite de la modélisation de joints collés pour les structures soumises à des sollicitations de type crash. Cette nouvelle modélisation basée sur un élément cohésif tient compte du comportement viscoplastique, de l'endommagement ainsi que de la rupture de l'adhésive. Sensible à la vitesse de déformation l'identification du critère de rupture nécessite une base expérimentale allant jusqu'à de très hautes vitesses de déformations. Un nouveau dispositif d'essais a donc été mis en place sur les barres de Hopkinson afin de solliciter des assemblages à haute vitesse et sous différents angles de chargement. This paper deals with the modeling of bonded joints for structures subjected to dynamic crash loading. This new model based on a cohesive element takes into account the viscoelastic behavior, the damage and the failure of the adhesive. Due to the strain rate sensitivity, the identification of failure criterion requires experimental tests, up to very high strain rates. A new testing device has then been set up on the Hopkinson bar in order to load the assemblies with high strain rates and with different angles.
Directory of Open Access Journals (Sweden)
Ulisse Cecini
2017-07-01
Full Text Available The Talmud manuscripts Magl. coll. II.I.8 and 9 of the Biblioteca Nazionale Centrale of Florence contain marginal Talmud-translations in Latin which correspond to the 13th century translation Extractiones de Talmud. The two manuscripts are described and their textual evidence is compared both with the Latin manuscript tradition of the Extractiones and with the Hebrew/Aramaic Talmudic text which they contain, trying to answer the question of whether the Florence manuscripts are the Vorlage of the Latin translation of the Talmud. The matter reveals itself as complex: striking analogies seem to suggest an affirmative answer to the question at stake; however, evidence can also be found which rather supports the opposite conclusion. Nevertheless, the Florence manuscripts certainly belong to a Hebrew/Aramaic tradition which is very close to the Vorlage of the Extractiones. Moreover, the Latin text they offer in their magins reflects a prior stage of work in the production of the Extractiones, featuring unique variants and passages, which are corrected or omitted in the rest of the Latin manuscript tradition.
Chun, Sehun
2017-07-01
Applying the method of moving frames to Maxwell's equations yields two important advancements for scientific computing. The first is the use of upwind flux for anisotropic materials in Maxwell's equations, especially in the context of discontinuous Galerkin (DG) methods. Upwind flux has been available only to isotropic material, because of the difficulty of satisfying the Rankine-Hugoniot conditions in anisotropic media. The second is to solve numerically Maxwell's equations on curved surfaces without the metric tensor and composite meshes. For numerical validation, spectral convergences are displayed for both two-dimensional anisotropic media and isotropic spheres. In the first application, invisible two-dimensional metamaterial cloaks are simulated with a relatively coarse mesh by both the lossless Drude model and the piecewisely-parametered layered model. In the second application, extremely low frequency propagation on various surfaces such as spheres, irregular surfaces, and non-convex surfaces is demonstrated.
Fowler, Kathryn; Connolly, Paul J.; Topping, David O.; O'Meara, Simon
2018-02-01
The composition of atmospheric aerosol particles has been found to influence their micro-physical properties and their interaction with water vapour in the atmosphere. Core-shell models have been used to investigate the relationship between composition, viscosity and equilibration timescales. These models have traditionally relied on the Fickian laws of diffusion with no explicit account of non-ideal interactions. We introduce the Maxwell-Stefan diffusion framework as an alternative method, which explicitly accounts for non-ideal interactions through activity coefficients. e-folding time is the time it takes for the difference in surface and bulk concentration to change by an exponential factor and was used to investigate the interplay between viscosity and solubility and the effect this has on equilibration timescales within individual aerosol particles. The e-folding time was estimated after instantaneous increases in relative humidity to binary systems of water and an organic component. At low water mole fractions, viscous effects were found to dominate mixing. However, at high water mole fractions, equilibration times were more sensitive to a range in solubility, shown through the greater variation in e-folding times. This is the first time the Maxwell-Stefan framework has been applied to an atmospheric aerosol core-shell model and shows that there is a complex interplay between the viscous and solubility effects on aerosol composition that requires further investigation.
Blaclard, G.; Vincenti, H.; Lehe, R.; Vay, J. L.
2017-09-01
With the advent of petawatt class lasers, the very large laser intensities attainable on target should enable the production of intense high-order Doppler harmonics from relativistic laser-plasma mirror interactions. At present, the modeling of these harmonics with particle-in-cell (PIC) codes is extremely challenging as it implies an accurate description of tens to hundreds of harmonic orders on a broad range of angles. In particular, we show here that due to the numerical dispersion of waves they induce in vacuum, standard finite difference time domain (FDTD) Maxwell solvers employed in most PIC codes can induce a spurious angular deviation of harmonic beams potentially degrading simulation results. This effect was extensively studied and a simple toy model based on the Snell-Descartes law was developed that allows us to finely predict the angular deviation of harmonics depending on the spatiotemporal resolution and the Maxwell solver used in the simulations. Our model demonstrates that the mitigation of this numerical artifact with FDTD solvers mandates very high spatiotemporal resolution preventing realistic three-dimensional (3D) simulations even on the largest computers available at the time of writing. We finally show that nondispersive pseudospectral analytical time domain solvers can considerably reduce the spatiotemporal resolution required to mitigate this spurious deviation and should enable in the near future 3D accurate modeling on supercomputers in a realistic time to solution.
Trivedi, Dhara J.; Wang, Danqing; Odom, Teri W.; Schatz, George C.
2017-11-01
We present a theoretical study of lasing action when plasmonic metallic structures that show lattice plasmon resonances are embedded in a gain medium. Our model combines classical electrodynamics for arrays of gold nanoparticles with a four-level quantum Liouville model of the laser dye photophysics. A numerical solution was implemented using finite-difference time-domain calculations coupled with a finite-difference solution to the Liouville equation. A particular focus of this work is the influence of dephasing in the quantum dynamics on the emission intensity at the threshold for lasing. We find that dephasing in the quantum system leads to reduced lasing emission, but with little effect on the long-term population inversion. Both electronic and vibrational dephasing is considered, but only electronic dephasing is significant, with the fully dephased result appearing for dephasing times comparable to plasmon dephasing (˜10 fs) while fully coherent results involve >100 ps dephasing times as determined by the rate of stimulated emission. There are factor-of-2 differences between the Maxwell-Liouville results (greater emission intensities and narrower widths) compared to the corresponding results of rate-equation models of the dye states, which indicates the importance of using the Maxwell-Liouville approach in modeling these systems. We also examine rate-equation models with and without constraints arising from the Pauli exclusion principle, and we find relatively small effects.
Wang, Q.; Liu, Z. J.; Zheng, C. Y.; Xiao, C. Z.; Feng, Q. S.; Zhang, H. C.; He, X. T.
2018-01-01
The longitudinal relativistic effect on stimulated Raman backscattering (SRBS) is investigated by using one-dimensional (1D) Vlasov-Maxwell simulations. Using a short backscattered light seed pulse with a very small amplitude, the linear gain spectra of SRBS in the strongly convective regime is presented by combining the relativistic and non-relativistic 1D Vlasov-Maxwell simulations, which is in agreement with the steady-state linear theory. More interestingly, by considering transition from convective to absolute instability due to electron trapping, we successfully predict the critical duration of the seed which can just trigger the kinetic inflation of the excited SRBS after the seed leaves the simulation box. The critical duration in the relativistic case is much shorter than that in the nonrelativistic case, which indicates that the kinetic inflation more easily occurs in the relativistic case than in the nonrelativistic case. In the weakly convective regime, the transition from convective to absolute instability for SRBS can directly occur in the linear regime due to the longitudinal relativistic modification. For the same pump, our simulations first demonstrate that the SRBS excited by a short and small seed pulse is a convective instability in the nonrelativistic case but becomes an absolute instability due to the decrease of the linear Landau damping from the longitudinal relativistic modification in the relativistic case. In more detail, the growth rate of the backscattered light is also in excellent agreement with theoretical prediction.