Elementary operators on self-adjoint operators
Molnar, Lajos; Semrl, Peter
2007-03-01
Let H be a Hilbert space and let and be standard *-operator algebras on H. Denote by and the set of all self-adjoint operators in and , respectively. Assume that and are surjective maps such that M(AM*(B)A)=M(A)BM(A) and M*(BM(A)B)=M*(B)AM*(B) for every pair , . Then there exist an invertible bounded linear or conjugate-linear operator and a constant c[set membership, variant]{-1,1} such that M(A)=cTAT*, , and M*(B)=cT*BT, .
Self-Adjointness Criterion for Operators in Fock Spaces
International Nuclear Information System (INIS)
Falconi, Marco
2015-01-01
In this paper we provide a criterion of essential self-adjointness for operators in the tensor product of a separable Hilbert space and a Fock space. The class of operators we consider may contain a self-adjoint part, a part that preserves the number of Fock space particles and a non-diagonal part that is at most quadratic with respect to the creation and annihilation operators. The hypotheses of the criterion are satisfied in several interesting applications
Self-adjointness and spectral properties of Dirac operators with magnetic links
DEFF Research Database (Denmark)
Portmann, Fabian; Sok, Jérémy; Solovej, Jan Philip
2018-01-01
We define Dirac operators on $\\mathbb{S}^3$ (and $\\mathbb{R}^3$) with magnetic fields supported on smooth, oriented links and prove self-adjointness of certain (natural) extensions. We then analyze their spectral properties and show, among other things, that these operators have discrete spectrum...
Spectral monodromy of non-self-adjoint operators
International Nuclear Information System (INIS)
Phan, Quang Sang
2014-01-01
In the present paper, we build a combinatorial invariant, called the “spectral monodromy” from the spectrum of a single (non-self-adjoint) h-pseudodifferential operator with two degrees of freedom in the semi-classical limit. Our inspiration comes from the quantum monodromy defined for the joint spectrum of an integrable system of n commuting self-adjoint h-pseudodifferential operators, given by S. Vu Ngoc [“Quantum monodromy in integrable systems,” Commun. Math. Phys. 203(2), 465–479 (1999)]. The first simple case that we treat in this work is a normal operator. In this case, the discrete spectrum can be identified with the joint spectrum of an integrable quantum system. The second more complex case we propose is a small perturbation of a self-adjoint operator with a classical integrability property. We show that the discrete spectrum (in a small band around the real axis) also has a combinatorial monodromy. The main difficulty in this case is that we do not know the description of the spectrum everywhere, but only in a Cantor type set. In addition, we also show that the corresponding monodromy can be identified with the classical monodromy, defined by J. Duistermaat [“On global action-angle coordinates,” Commun. Pure Appl. Math. 33(6), 687–706 (1980)
Spectral monodromy of non-self-adjoint operators
Energy Technology Data Exchange (ETDEWEB)
Phan, Quang Sang, E-mail: quang.phan@uj.edu.pl [Université de Rennes 1, Institut de Recherche Mathématique de Rennes (UMR 6625), Campus de Beaulieu, 35042 Rennes (France)
2014-01-15
In the present paper, we build a combinatorial invariant, called the “spectral monodromy” from the spectrum of a single (non-self-adjoint) h-pseudodifferential operator with two degrees of freedom in the semi-classical limit. Our inspiration comes from the quantum monodromy defined for the joint spectrum of an integrable system of n commuting self-adjoint h-pseudodifferential operators, given by S. Vu Ngoc [“Quantum monodromy in integrable systems,” Commun. Math. Phys. 203(2), 465–479 (1999)]. The first simple case that we treat in this work is a normal operator. In this case, the discrete spectrum can be identified with the joint spectrum of an integrable quantum system. The second more complex case we propose is a small perturbation of a self-adjoint operator with a classical integrability property. We show that the discrete spectrum (in a small band around the real axis) also has a combinatorial monodromy. The main difficulty in this case is that we do not know the description of the spectrum everywhere, but only in a Cantor type set. In addition, we also show that the corresponding monodromy can be identified with the classical monodromy, defined by J. Duistermaat [“On global action-angle coordinates,” Commun. Pure Appl. Math. 33(6), 687–706 (1980)].
Spectral monodromy of non-self-adjoint operators
Phan, Quang Sang
2014-01-01
In the present paper, we build a combinatorial invariant, called the "spectral monodromy" from the spectrum of a single (non-self-adjoint) h-pseudodifferential operator with two degrees of freedom in the semi-classical limit. Our inspiration comes from the quantum monodromy defined for the joint spectrum of an integrable system of n commuting self-adjoint h-pseudodifferential operators, given by S. Vu Ngoc ["Quantum monodromy in integrable systems," Commun. Math. Phys. 203(2), 465-479 (1999)]. The first simple case that we treat in this work is a normal operator. In this case, the discrete spectrum can be identified with the joint spectrum of an integrable quantum system. The second more complex case we propose is a small perturbation of a self-adjoint operator with a classical integrability property. We show that the discrete spectrum (in a small band around the real axis) also has a combinatorial monodromy. The main difficulty in this case is that we do not know the description of the spectrum everywhere, but only in a Cantor type set. In addition, we also show that the corresponding monodromy can be identified with the classical monodromy, defined by J. Duistermaat ["On global action-angle coordinates," Commun. Pure Appl. Math. 33(6), 687-706 (1980)].
Perturbation of self-adjoint operators by Dirac distributions
International Nuclear Information System (INIS)
Zorbas, J.
1980-01-01
The existence of a family of self-adjoint Hamiltonians H/sub theta/, theta element of [0, 2π), corresponding to the formal expression H 0 +νdelta (x) is shown for a general class of self-adjoint operators H 0 . Expressions for the Green's function and wavefunction corresponding to H/sub theta/ are obtained in terms of the Green's function and wavefunction corresponding to H 0 . Similar results are shown for the perturbation of H 0 by a finite sum of Dirac distributions. A prescription is given for obtaining H/sub theta/ as the strong resolvent limit of a family of momentum cutoff Hamiltonians H/sup N/. The relationship between the scattering theories corresponding to H/sup N/ and H/sub theta/ is examined
Self-adjoint oscillator operator from a modified factorization
Energy Technology Data Exchange (ETDEWEB)
Reyes, Marco A. [Departamento de Fisica, DCI Campus Leon, Universidad de Guanajuato, Apdo. Postal E143, 37150 Leon, Gto. (Mexico); Rosu, H.C., E-mail: hcr@ipicyt.edu.mx [IPICyT, Instituto Potosino de Investigacion Cientifica y Tecnologica, Apdo. Postal 3-74 Tangamanga, 78231 San Luis Potosi, S.L.P. (Mexico); Gutierrez, M. Ranferi [Departamento de Fisica, DCI Campus Leon, Universidad de Guanajuato, Apdo. Postal E143, 37150 Leon, Gto. (Mexico)
2011-05-30
By using an alternative factorization, we obtain a self-adjoint oscillator operator of the form L{sub δ}=d/(dx) (p{sub δ}(x)d/(dx) )-((x{sup 2})/(p{sub δ}(x)) +p{sub δ}(x)-1), where p{sub δ}(x)=1+δe{sup -x{sup 2}}, with δ element of (-1,∞) an arbitrary real factorization parameter. At positive values of δ, this operator interpolates between the quantum harmonic oscillator Hamiltonian for δ=0 and a scaled Hermite operator at high values of δ. For the negative values of δ, the eigenfunctions look like deformed quantum mechanical Hermite functions. Possible applications are mentioned. -- Highlights: → We present a generalization of the Mielnik factorization. → We study the case of linear relationship between the factorization coefficients. → We introduce a new one-parameter self-adjoint oscillator operator. → We show its properties depending on the values of the parameter.
Characterization and uniqueness of distinguished self-adjoint extensions of dirac operators
International Nuclear Information System (INIS)
Klaus, M.; Wuest, R.; Princeton Univ., NJ
1979-01-01
Distinguished self-adjoint extensions of Dirac operators are characterized by Nenciu and constructed by means of cut-off potentials by Wuest. In this paper it is shown that the existence and a more explicit characterization of Nenciu's self-adjoint extensions can be obtained as a consequence from results of the cut-off method, that these extensions are the same as the extensions constructed with cut-off potentials and that they are unique in some sense. (orig.) [de
Feynman's Operational Calculi: Spectral Theory for Noncommuting Self-adjoint Operators
International Nuclear Information System (INIS)
Jefferies, Brian; Johnson, Gerald W.; Nielsen, Lance
2007-01-01
The spectral theorem for commuting self-adjoint operators along with the associated functional (or operational) calculus is among the most useful and beautiful results of analysis. It is well known that forming a functional calculus for noncommuting self-adjoint operators is far more problematic. The central result of this paper establishes a rich functional calculus for any finite number of noncommuting (i.e. not necessarily commuting) bounded, self-adjoint operators A 1 ,..., A n and associated continuous Borel probability measures μ 1 , ?, μ n on [0,1]. Fix A 1 ,..., A n . Then each choice of an n-tuple (μ 1 ,...,μ n ) of measures determines one of Feynman's operational calculi acting on a certain Banach algebra of analytic functions even when A 1 , ..., A n are just bounded linear operators on a Banach space. The Hilbert space setting along with self-adjointness allows us to extend the operational calculi well beyond the analytic functions. Using results and ideas drawn largely from the proof of our main theorem, we also establish a family of Trotter product type formulas suitable for Feynman's operational calculi
Spectral analysis of non-self-adjoint Jacobi operator associated with Jacobian elliptic functions
Czech Academy of Sciences Publication Activity Database
Siegl, Petr; Štampach, F.
2017-01-01
Roč. 11, č. 4 (2017), s. 901-928 ISSN 1846-3886 Grant - others:GA ČR(CZ) GA13-11058S Institutional support: RVO:61389005 Keywords : Non-self-adjoint Jacobi operator * Weyl m-function * Jacobian elliptic functions Subject RIV: BE - Theoretical Physics OBOR OECD: Pure mathematics Impact factor: 0.440, year: 2016
An introduction to the self-adjointness and spectral analysis of Schroedinger operators
International Nuclear Information System (INIS)
Simon, B.
1977-01-01
The author first explains the basic results about self adjointness, from a point of view which emphasizes the connection with solvability of the Schroedinger equation. He then describes four methods that define self ajoint Hamiltonians, for most Schroedinger operators and discusses types of spectra, closing by considering the essential spectrum in the two body case. (P.D.)
Self-adjoint elliptic operators with boundary conditions on not closed hypersurfaces
Mantile, Andrea; Posilicano, Andrea; Sini, Mourad
2016-07-01
The theory of self-adjoint extensions of symmetric operators is used to construct self-adjoint realizations of a second-order elliptic differential operator on Rn with linear boundary conditions on (a relatively open part of) a compact hypersurface. Our approach allows to obtain Kreĭn-like resolvent formulae where the reference operator coincides with the ;free; operator with domain H2 (Rn); this provides an useful tool for the scattering problem from a hypersurface. Concrete examples of this construction are developed in connection with the standard boundary conditions, Dirichlet, Neumann, Robin, δ and δ‧-type, assigned either on a (n - 1) dimensional compact boundary Γ = ∂ Ω or on a relatively open part Σ ⊂ Γ. Schatten-von Neumann estimates for the difference of the powers of resolvents of the free and the perturbed operators are also proven; these give existence and completeness of the wave operators of the associated scattering systems.
Absence of singular continuous spectrum for certain self-adjoint operators
International Nuclear Information System (INIS)
Mourre, E.
1979-01-01
An adequate condition is given for a self-adjoint operator to show in the vinicity of a point E of its spectrum the following properties: its point spectrum is of finite size; its singular continuous spectrum is empty. In the way of new applications the absence of singular continuous spectrum is demonstrated in the following two cases: perturbations of pseudo-differential operators; Schroedinger operators of a three-body system [fr
Green's matrix for a second-order self-adjoint matrix differential operator
International Nuclear Information System (INIS)
Sisman, Tahsin Cagri; Tekin, Bayram
2010-01-01
A systematic construction of the Green's matrix for a second-order self-adjoint matrix differential operator from the linearly independent solutions of the corresponding homogeneous differential equation set is carried out. We follow the general approach of extracting the Green's matrix from the Green's matrix of the corresponding first-order system. This construction is required in the cases where the differential equation set cannot be turned to an algebraic equation set via transform techniques.
International Nuclear Information System (INIS)
Bayramoglu, Mehmet; Tasci, Fatih; Zeynalov, Djafar
2004-01-01
We study the discrete part of spectrum of a singular non-self-adjoint second-order differential equation on a semiaxis with an operator coefficient. Its boundedness is proved. The result is applied to the Schroedinger boundary value problem -Δu+q(x)u=λ 2 u, u vertical bar ∂D =0, with a complex potential q(x) in an angular domain
Discrete SLn-connections and self-adjoint difference operators on 2-dimensional manifolds
International Nuclear Information System (INIS)
Grinevich, P G; Novikov, S P
2013-01-01
The programme of discretization of famous completely integrable systems and associated linear operators was launched in the 1990s. In particular, the properties of second-order difference operators on triangulated manifolds and equilateral triangular lattices have been studied by Novikov and Dynnikov since 1996. This study included Laplace transformations, new discretizations of complex analysis, and new discretizations of GL n -connections on triangulated n-dimensional manifolds. A general theory of discrete GL n -connections 'of rank one' has been developed (see the Introduction for definitions). The problem of distinguishing the subclass of SL n -connections (and unimodular SL n ± -connections, which satisfy detA = ±1) has not been solved. In the present paper it is shown that these connections play an important role (which is similar to the role of magnetic fields in the continuous case) in the theory of self-adjoint Schrödinger difference operators on equilateral triangular lattices in ℝ 2 . In Appendix 1 a complete characterization is given of unimodular SL n ± -connections of rank 1 for all n > 1, thus correcting a mistake (it was wrongly claimed that they reduce to a canonical connection for n > 2). With the help of a communication from Korepanov, a complete clarification is provided of how the classical theory of electrical circuits and star-triangle transformations is connected with the discrete Laplace transformations on triangular lattices. Bibliography: 29 titles
Spectral multipliers on spaces of distributions associated with non-negative self-adjoint operators
DEFF Research Database (Denmark)
Georgiadis, Athanasios; Nielsen, Morten
2018-01-01
and Triebel–Lizorkin spaces with full range of indices is established too. As an application, we obtain equivalent norm characterizations for the spaces mentioned above. Non-classical spaces as well as Lebesgue, Hardy, (generalized) Sobolev and Lipschitz spaces are also covered by our approach.......We consider spaces of homogeneous type associated with a non-negative self-adjoint operator whose heat kernel satisfies certain upper Gaussian bounds. Spectral multipliers are introduced and studied on distributions associated with this operator. The boundedness of spectral multipliers on Besov...
Diagonalization of a self-adjoint operator acting on a Hilbert module
Directory of Open Access Journals (Sweden)
Parfeny P. Saworotnow
1985-01-01
Full Text Available For each bounded self-adjoint operator T on a Hilbert module H over an H*-algebra A there exists a locally compact space m and a certain A-valued measure μ such that H is isomorphic to L2(μ⊗A and T corresponds to a multiplication with a continuous function. There is a similar result for a commuting family of normal operators. A consequence for this result is a representation theorem for generalized stationary processes.
The method of rigged spaces in singular perturbation theory of self-adjoint operators
Koshmanenko, Volodymyr; Koshmanenko, Nataliia
2016-01-01
This monograph presents the newly developed method of rigged Hilbert spaces as a modern approach in singular perturbation theory. A key notion of this approach is the Lax-Berezansky triple of Hilbert spaces embedded one into another, which specifies the well-known Gelfand topological triple. All kinds of singular interactions described by potentials supported on small sets (like the Dirac δ-potentials, fractals, singular measures, high degree super-singular expressions) admit a rigorous treatment only in terms of the equipped spaces and their scales. The main idea of the method is to use singular perturbations to change inner products in the starting rigged space, and the construction of the perturbed operator by the Berezansky canonical isomorphism (which connects the positive and negative spaces from a new rigged triplet). The approach combines three powerful tools of functional analysis based on the Birman-Krein-Vishik theory of self-adjoint extensions of symmetric operators, the theory of singular quadra...
Eijndhoven, van S.J.L.; Graaf, de J.
1986-01-01
A new theory of generalized functions has been developed by one of the authors (de Graaf). In this theory the analyticity domain of each positive self-adjoint unbounded operator $\\mathcal{A}$ in a Hilbert space $X$ is regarded as a test space denoted by $\\mathcal{S}_{x,\\mathcal{A}} $. In the first
International Nuclear Information System (INIS)
Arcos-Olalla, Rafael; Reyes, Marco A.; Rosu, Haret C.
2012-01-01
We introduce an alternative factorization of the Hamiltonian of the quantum harmonic oscillator which leads to a two-parameter self-adjoint operator from which the standard harmonic oscillator, the one-parameter oscillators introduced by Mielnik, and the Hermite operator are obtained in certain limits of the parameters. In addition, a single Bernoulli-type parameter factorization, which is different from the one introduced by M.A. Reyes, H.C. Rosu, and M.R. Gutiérrez [Phys. Lett. A 375 (2011) 2145], is briefly discussed in the final part of this work. -- Highlights: ► Factorizations with operators which are not mutually adjoint are presented. ► New two-parameter and one-parameter self-adjoint oscillator operators are introduced. ► Their eigenfunctions are two- and one-parameter deformed Hermite functions.
Energy Technology Data Exchange (ETDEWEB)
Arcos-Olalla, Rafael, E-mail: olalla@fisica.ugto.mx [Departamento de Física, DCI Campus León, Universidad de Guanajuato, Apdo. Postal E143, 37150 León, Gto. (Mexico); Reyes, Marco A., E-mail: marco@fisica.ugto.mx [Departamento de Física, DCI Campus León, Universidad de Guanajuato, Apdo. Postal E143, 37150 León, Gto. (Mexico); Rosu, Haret C., E-mail: hcr@ipicyt.edu.mx [IPICYT, Instituto Potosino de Investigacion Cientifica y Tecnologica, Apdo. Postal 3-74 Tangamanga, 78231 San Luis Potosí, S.L.P. (Mexico)
2012-10-01
We introduce an alternative factorization of the Hamiltonian of the quantum harmonic oscillator which leads to a two-parameter self-adjoint operator from which the standard harmonic oscillator, the one-parameter oscillators introduced by Mielnik, and the Hermite operator are obtained in certain limits of the parameters. In addition, a single Bernoulli-type parameter factorization, which is different from the one introduced by M.A. Reyes, H.C. Rosu, and M.R. Gutiérrez [Phys. Lett. A 375 (2011) 2145], is briefly discussed in the final part of this work. -- Highlights: ► Factorizations with operators which are not mutually adjoint are presented. ► New two-parameter and one-parameter self-adjoint oscillator operators are introduced. ► Their eigenfunctions are two- and one-parameter deformed Hermite functions.
Determination of the self-adjoint matrix Schrödinger operators without the bound state data
Xu, Xiao-Chuan; Yang, Chuan-Fu
2018-06-01
(i) For the matrix Schrödinger operator on the half line, it is shown that the scattering data, which consists of the scattering matrix and the bound state data, uniquely determines the potential and the boundary condition. It is also shown that only the scattering matrix uniquely determines the self-adjoint potential and the boundary condition if either the potential exponentially decreases fast enough or the potential is known a priori on (), where a is an any fixed positive number. (ii) For the matrix Schrödinger operator on the full line, it is shown that the left (or right) reflection coefficient uniquely determine the self-adjoint potential if either the potential exponentially decreases fast enough or the potential is known a priori on (or ()), where b is an any fixed number.
Czech Academy of Sciences Publication Activity Database
Krejčiřík, David; Siegl, Petr; Železný, Jakub
2014-01-01
Roč. 8, č. 1 (2014), s. 255-281 ISSN 1661-8254 R&D Projects: GA MŠk LC06002; GA MŠk LC527; GA ČR GAP203/11/0701 Grant - others:GA ČR(CZ) GD202/08/H072 Institutional support: RVO:61389005 Keywords : Sturm-Liouville operators * non-symmetric Robin boundary conditions * similarity to normal or self-adjoint operators * discrete spectral operator * complex symmetric operator * PT-symmetry * metric operator * C operator * Hilbert- Schmidt operators Subject RIV: BE - Theoretical Physics Impact factor: 0.545, year: 2014
Zeta function of self-adjoint operators on surfaces of revolution
International Nuclear Information System (INIS)
Lu, Tianshi; Jeffres, Thalia; Kirsten, Klaus
2015-01-01
In this article we analyze the zeta function for the Laplace operator on a surface of revolution. A variety of boundary conditions, separated and unseparated, are considered. Formulas for several residues and values of the zeta function as well as for the determinant of the Laplacian are obtained. The analysis is based upon contour integration techniques in combination with a WKB analysis of solutions of related initial value problems. (paper)
Non-self-adjoint Schrödinger operators with nonlocal one-point interactions
Czech Academy of Sciences Publication Activity Database
Kuzhel, S.; Znojil, Miloslav
2017-01-01
Roč. 11, č. 4 (2017), s. 923-944 ISSN 1735-8787 R&D Projects: GA ČR GA16-22945S Institutional support: RVO:61389005 Keywords : 1-dimensional Schrodinger operator * nonlocal one-point interactions * boundary triplet Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 0.833, year: 2016
RT-Symmetric Laplace Operators on Star Graphs: Real Spectrum and Self-Adjointness
Directory of Open Access Journals (Sweden)
Maria Astudillo
2015-01-01
Full Text Available How ideas of PT-symmetric quantum mechanics can be applied to quantum graphs is analyzed, in particular to the star graph. The class of rotationally symmetric vertex conditions is analyzed. It is shown that all such conditions can effectively be described by circulant matrices: real in the case of odd number of edges and complex having particular block structure in the even case. Spectral properties of the corresponding operators are discussed.
Self-adjointness of the Gaffney Laplacian on Vector Bundles
Energy Technology Data Exchange (ETDEWEB)
Bandara, Lashi, E-mail: lashi.bandara@chalmers.se [Chalmers University of Technology and University of Gothenburg, Mathematical Sciences (Sweden); Milatovic, Ognjen, E-mail: omilatov@unf.edu [University of North Florida, Department of Mathematics and Statistics (United States)
2015-12-15
We study the Gaffney Laplacian on a vector bundle equipped with a compatible metric and connection over a Riemannian manifold that is possibly geodesically incomplete. Under the hypothesis that the Cauchy boundary is polar, we demonstrate the self-adjointness of this Laplacian. Furthermore, we show that negligible boundary is a necessary and sufficient condition for the self-adjointness of this operator.
Self-adjointness of the Gaffney Laplacian on Vector Bundles
International Nuclear Information System (INIS)
Bandara, Lashi; Milatovic, Ognjen
2015-01-01
We study the Gaffney Laplacian on a vector bundle equipped with a compatible metric and connection over a Riemannian manifold that is possibly geodesically incomplete. Under the hypothesis that the Cauchy boundary is polar, we demonstrate the self-adjointness of this Laplacian. Furthermore, we show that negligible boundary is a necessary and sufficient condition for the self-adjointness of this operator
Self-adjoint extensions and spectral analysis in the generalized Kratzer problem
International Nuclear Information System (INIS)
Baldiotti, M C; Gitman, D M; Tyutin, I V; Voronov, B L
2011-01-01
We present a mathematically rigorous quantum-mechanical treatment of a one-dimensional non-relativistic motion of a particle in the potential field V(x)=g 1 x -1 +g 2 x -2 , x is an element of R + = [0, ∞). For g 2 >0 and g 1 K (x) and is usually used to describe molecular energy and structure, interactions between different molecules and interactions between non-bonded atoms. We construct all self-adjoint Schroedinger operators with the potential V(x) and represent rigorous solutions of the corresponding spectral problems. Solving the first part of the problem, we use a method of specifying self-adjoint extensions by (asymptotic) self-adjoint boundary conditions. Solving spectral problems, we follow Krein's method of guiding functionals. This work is a continuation of our previous works devoted to the Coulomb, Calogero and Aharonov-Bohm potentials.
Weak self-adjoint differential equations
International Nuclear Information System (INIS)
Gandarias, M L
2011-01-01
The concepts of self-adjoint and quasi self-adjoint equations were introduced by Ibragimov (2006 J. Math. Anal. Appl. 318 742-57; 2007 Arch. ALGA 4 55-60). In Ibragimov (2007 J. Math. Anal. Appl. 333 311-28), a general theorem on conservation laws was proved. In this paper, we generalize the concept of self-adjoint and quasi self-adjoint equations by introducing the definition of weak self-adjoint equations. We find a class of weak self-adjoint quasi-linear parabolic equations. The property of a differential equation to be weak self-adjoint is important for constructing conservation laws associated with symmetries of the differential equation. (fast track communication)
Self-adjoint extensions and spectral analysis in the Calogero problem
International Nuclear Information System (INIS)
Gitman, D M; Tyutin, I V; Voronov, B L
2010-01-01
In this paper, we present a mathematically rigorous quantum-mechanical treatment of a one-dimensional motion of a particle in the Calogero potential αx -2 . Although the problem is quite old and well studied, we believe that our consideration based on a uniform approach to constructing a correct quantum-mechanical description for systems with singular potentials and/or boundaries, proposed in our previous works, adds some new points to its solution. To demonstrate that a consideration of the Calogero problem requires mathematical accuracy, we discuss some 'paradoxes' inherent in the 'naive' quantum-mechanical treatment. Using a self-adjoint extension method, we construct and study all possible self-adjoint operators (self-adjoint Hamiltonians) associated with a formal differential expression for the Calogero Hamiltonian. In particular, we discuss a spontaneous scale-symmetry breaking associated with self-adjoint extensions. A complete spectral analysis of all self-adjoint Hamiltonians is presented.
Non-self-adjoint hamiltonians defined by Riesz bases
Energy Technology Data Exchange (ETDEWEB)
Bagarello, F., E-mail: fabio.bagarello@unipa.it [Dipartimento di Energia, Ingegneria dell' Informazione e Modelli Matematici, Facoltà di Ingegneria, Università di Palermo, I-90128 Palermo, Italy and INFN, Università di Torino, Torino (Italy); Inoue, A., E-mail: a-inoue@fukuoka-u.ac.jp [Department of Applied Mathematics, Fukuoka University, Fukuoka 814-0180 (Japan); Trapani, C., E-mail: camillo.trapani@unipa.it [Dipartimento di Matematica e Informatica, Università di Palermo, I-90123 Palermo (Italy)
2014-03-15
We discuss some features of non-self-adjoint Hamiltonians with real discrete simple spectrum under the assumption that the eigenvectors form a Riesz basis of Hilbert space. Among other things, we give conditions under which these Hamiltonians can be factorized in terms of generalized lowering and raising operators.
Self-adjoint extensions and spectral analysis in the generalized Kratzer problem
Energy Technology Data Exchange (ETDEWEB)
Baldiotti, M C; Gitman, D M [Institute of Physics, University of Sao Paulo (Brazil); Tyutin, I V; Voronov, B L, E-mail: baldiott@fma.if.usp.br, E-mail: gitman@dfn.if.usp.br, E-mail: tyutin@lpi.ru, E-mail: voronov@lpi.ru [Lebedev Physical Institute, Moscow (Russian Federation)
2011-06-01
We present a mathematically rigorous quantum-mechanical treatment of a one-dimensional non-relativistic motion of a particle in the potential field V(x)=g{sub 1}x{sup -1}+g{sub 2}x{sup -2}, x is an element of R{sub +} = [0, {infinity}). For g{sub 2}>0 and g{sub 1}<0, the potential is known as the Kratzer potential V{sub K}(x) and is usually used to describe molecular energy and structure, interactions between different molecules and interactions between non-bonded atoms. We construct all self-adjoint Schroedinger operators with the potential V(x) and represent rigorous solutions of the corresponding spectral problems. Solving the first part of the problem, we use a method of specifying self-adjoint extensions by (asymptotic) self-adjoint boundary conditions. Solving spectral problems, we follow Krein's method of guiding functionals. This work is a continuation of our previous works devoted to the Coulomb, Calogero and Aharonov-Bohm potentials.
Self-adjoint extensions and spectral analysis in the Calogero problem
Energy Technology Data Exchange (ETDEWEB)
Gitman, D M [Institute of Physics, University of Sao Paulo (Brazil); Tyutin, I V; Voronov, B L [Lebedev Physical Institute, Moscow (Russian Federation)], E-mail: gitman@dfn.if.usp.br, E-mail: tyutin@lpi.ru, E-mail: voronov@lpi.ru
2010-04-09
In this paper, we present a mathematically rigorous quantum-mechanical treatment of a one-dimensional motion of a particle in the Calogero potential {alpha}x{sup -2}. Although the problem is quite old and well studied, we believe that our consideration based on a uniform approach to constructing a correct quantum-mechanical description for systems with singular potentials and/or boundaries, proposed in our previous works, adds some new points to its solution. To demonstrate that a consideration of the Calogero problem requires mathematical accuracy, we discuss some 'paradoxes' inherent in the 'naive' quantum-mechanical treatment. Using a self-adjoint extension method, we construct and study all possible self-adjoint operators (self-adjoint Hamiltonians) associated with a formal differential expression for the Calogero Hamiltonian. In particular, we discuss a spontaneous scale-symmetry breaking associated with self-adjoint extensions. A complete spectral analysis of all self-adjoint Hamiltonians is presented.
Propagators in magnetic string background and the problem of self-adjoint extensions
International Nuclear Information System (INIS)
Kaiser, H.J.
1993-01-01
Ghost and gluon propagators of a non-Abelian gauge theory in the background of a magnetic string are calculated. A simple technique to derive the ghost propagator is presented which makes use of the fact that the presence of a magnetic string of strength β shifts the differential operators ∂/∂φ to ∂/∂φ - iβ. In the case of a gluon propagator in the magnetic string background a difficulty arises from the presence of the magnetic field strength term involving a δ function. Here the ambiguities of a self-adjoint extension of the differential operator must be met. A proper treatment demands the specification of a limiting process starting from a string of finite thickness and well-defined structure and leading to the δ function string. Without this additional structure information about the background string the gauge field propagator is undetermined. (orig.)
Schrödinger and Dirac operators with the Aharonov-Bohm and magnetic-solenoid fields
International Nuclear Information System (INIS)
Gitman, D M; Tyutin, I V; Voronov, B L
2012-01-01
We construct all self-adjoint Schrödinger and Dirac operators (Hamiltonians) with both the pure Aharonov-Bohm (AB) field and the so-called magnetic-solenoid field (a collinear superposition of the AB field and a constant magnetic field). We perform a spectral analysis for these operators, which includes finding spectra and spectral decompositions, or inversion formulae. In constructing the Hamiltonians and performing their spectral analysis, we follow, respectively, the von Neumann theory of self-adjoint extensions of symmetric operators and the Krein method of guiding functionals. (paper)
Oscillator representations for self-adjoint Calogero Hamiltonians
Energy Technology Data Exchange (ETDEWEB)
Gitman, D M [Institute of Physics, University of Sao Paulo (Brazil); Tyutin, I V; Voronov, B L, E-mail: gitman@dfn.if.usp.br, E-mail: tyutin@lpi.ru, E-mail: voronov@lpi.ru [Lebedev Physical Institute, Moscow (Russian Federation)
2011-10-21
In Gitman et al (2010 J. Phys. A: Math. Theor. 43 145205), we presented a mathematically rigorous quantum-mechanical treatment of a one-dimensional motion of a particle in the Calogero potential V(x) = {alpha}x{sup -2}. We described all possible self-adjoint (s.a.) operators (s.a. Hamiltonians) associated with the differential operation H=-d{sub x}{sup 2}+{alpha}x{sup -2} for the Calogero Hamiltonian. Here, we discuss a new aspect of the problem, the so-called oscillator representations for the Calogero Hamiltonians. As is known, operators of the form N-hat = a-hat{sup +} a-hat and A-hat = a-hat a-hat{sup +} are called operators of oscillator type. Oscillator-type operators possess a number of useful properties in the case when the elementary operators a-hat are closed. It turns out that some s.a. Calogero Hamiltonians allow oscillator-type representations. We describe such Hamiltonians and find the corresponding mutually adjoint elementary operators a-hat and a-hat{sup +}. An oscillator-type representation for a given Hamiltonian is generally not unique. (paper)
Oscillator representations for self-adjoint Calogero Hamiltonians
International Nuclear Information System (INIS)
Gitman, D M; Tyutin, I V; Voronov, B L
2011-01-01
In Gitman et al (2010 J. Phys. A: Math. Theor. 43 145205), we presented a mathematically rigorous quantum-mechanical treatment of a one-dimensional motion of a particle in the Calogero potential V(x) = αx -2 . We described all possible self-adjoint (s.a.) operators (s.a. Hamiltonians) associated with the differential operation H=-d x 2 +αx -2 for the Calogero Hamiltonian. Here, we discuss a new aspect of the problem, the so-called oscillator representations for the Calogero Hamiltonians. As is known, operators of the form N-hat = a-hat + a-hat and A-hat = a-hat a-hat + are called operators of oscillator type. Oscillator-type operators possess a number of useful properties in the case when the elementary operators a-hat are closed. It turns out that some s.a. Calogero Hamiltonians allow oscillator-type representations. We describe such Hamiltonians and find the corresponding mutually adjoint elementary operators a-hat and a-hat + . An oscillator-type representation for a given Hamiltonian is generally not unique. (paper)
Surface spectra of Weyl semimetals through self-adjoint extensions
Seradjeh, Babak; Vennettilli, Michael
2018-02-01
We apply the method of self-adjoint extensions of Hermitian operators to the low-energy, continuum Hamiltonians of Weyl semimetals in bounded geometries and derive the spectrum of the surface states on the boundary. This allows for the full characterization of boundary conditions and the surface spectra on surfaces both normal to the Weyl node separation as well as parallel to it. We show that the boundary conditions for quadratic bulk dispersions are, in general, specified by a U (2 ) matrix relating the wave function and its derivatives normal to the surface. We give a general procedure to obtain the surface spectra from these boundary conditions and derive them in specific cases of bulk dispersion. We consider the role of global symmetries in the boundary conditions and their effect on the surface spectrum. We point out several interesting features of the surface spectra for different choices of boundary conditions, such as a Mexican-hat shaped dispersion on the surface normal to Weyl node separation. We find that the existence of bound states, Fermi arcs, and the shape of their dispersion, depend on the choice of boundary conditions. This illustrates the importance of the physics at and near the boundaries in the general statement of bulk-boundary correspondence.
Explicit isospectral flows for the AKNS operator on the unit interval
International Nuclear Information System (INIS)
Amour, L
2009-01-01
We consider the AKNS operator on the unit interval. The boundary conditions are self-adjoint separated boundary conditions. For fixed boundary conditions, we make the formulae for flows induced by general tangent vector fields on isospectral sets explicit
Scattering theory for self-adjoint extensions
International Nuclear Information System (INIS)
Kuperin, Yu.A.; Pavlov, B.S.; Kurasov, P.B.; Makarov, K.A.; Melnikov, Yu. B.; Yevstratov, V.V
1989-01-01
In this paper a new approach is suggested to the construction of a wide class of exactly solvable quantum-mechanical models of scattering, quantum-mechanical models of solids and an exactly solvable quantum-stochastical model. For most of the models the spectral analysis is performed in an explicit form, for many body problems it is reduced to one-dimensional integral equations. The construction of all models is based on a new version of extension theory, which uses the boundary forms for abstract operators. This version gives a simple and general method to join the pair of operators, one of them abstract, and the other one differential. The solvability of these models is based on Krein's formula for quasiresolvents
Resolvent convergence in norm for Dirac operator with Aharonov-Bohm field
International Nuclear Information System (INIS)
Tamura, Hideo
2003-01-01
We consider the Hamiltonian for relativistic particles moving in the Aharonov-Bohm magnetic field in two dimensions. The field has δ-like singularity at the origin, and the Hamiltonian is not necessarily essentially self-adjoint. The self-adjoint realization requires one parameter family of boundary conditions at the origin. We approximate the point-like field by smooth ones and study the problem of norm resolvent convergence to see which boundary condition is physically reasonable among admissible boundary conditions. We also study the effect of perturbations by scalar potentials. Roughly speaking, the obtained result is that the limit self-adjoint realization is different even for small perturbation of scalar potentials according to the values of magnetic fluxes. It changes at half-integer fluxes. The method is based on the resolvent analysis at low energy on magnetic Schroedinger operators with resonance at zero energy and the resonance plays an important role from a mathematical point of view. However it has been neglected in earlier physical works. The emphasis here is placed on this natural aspect
Almost commuting self-adjoint matrices: The real and self-dual cases
Loring, Terry A.; Sørensen, Adam P. W.
2016-08-01
We show that a pair of almost commuting self-adjoint, symmetric matrices is close to a pair of commuting self-adjoint, symmetric matrices (in a uniform way). Moreover, we prove that the same holds with self-dual in place of symmetric and also for paths of self-adjoint matrices. Since a symmetric, self-adjoint matrix is real, we get a real version of Huaxin Lin’s famous theorem on almost commuting matrices. Similarly, the self-dual case gives a version for matrices over the quaternions. To prove these results, we develop a theory of semiprojectivity for real C*-algebras and also examine various definitions of low-rank for real C*-algebras.
Spatial discretizations for self-adjoint forms of the radiative transfer equations
International Nuclear Information System (INIS)
Morel, Jim E.; Adams, B. Todd; Noh, Taewan; McGhee, John M.; Evans, Thomas M.; Urbatsch, Todd J.
2006-01-01
There are three commonly recognized second-order self-adjoint forms of the neutron transport equation: the even-parity equations, the odd-parity equations, and the self-adjoint angular flux equations. Because all of these equations contain second-order spatial derivatives and are self-adjoint for the mono-energetic case, standard continuous finite-element discretization techniques have proved quite effective when applied to the spatial variables. We first derive analogs of these equations for the case of time-dependent radiative transfer. The primary unknowns for these equations are functions of the angular intensity rather than the angular flux, hence the analog of the self-adjoint angular flux equation is referred to as the self-adjoint angular intensity equation. Then we describe a general, arbitrary-order, continuous spatial finite-element approach that is applied to each of the three equations in conjunction with backward-Euler differencing in time. We refer to it as the 'standard' technique. We also introduce an alternative spatial discretization scheme for the self-adjoint angular intensity equation that requires far fewer unknowns than the standard method, but appears to give comparable accuracy. Computational results are given that demonstrate the validity of both of these discretization schemes
Trotter-Kato product formula and fractional powers of self-adjoint generators
Ichinose, I; Zagrebnov, Z
2002-01-01
Let $A$ and $B$ be non-negative self-adjoint operators in a Hilbert space such that their densely defined form sum $H = A \\stackrel{\\cdot}{+} B$ obeys $\\dom(H^\\ga) \\subseteq \\dom(A^\\ga) \\cap \\dom(B^\\ga)$ for some $\\ga \\in (1/2,1)$. It is proved that if, in addition, $A$ and $B$ satisfy $\\dom(A^{1/2}) \\subseteq \\dom(B^{1/2})$, then the symmetric and non-symmetric Trotter-Kato product formula converges in the operator norm: % % \\bed \\ba{c} \\left\\|\\left(e^{-tB/2n}e^{-tA/n}e^{-tB/2n}\\right)^n - e^{-tH}\\right\\| = O(n^{-(2\\ga-1)}), \\\\[2mm] \\left\\|\\left(e^{-tA/n}e^{-tB/n}\\right)^n - e^{-tH}\\right\\| = O(n^{-(2\\ga-1)}) \\ea \\eed % % uniformly in $t \\in [0,T]$, $0 < T < \\infty$, as $n \\to \\infty$, both with the same optimal error bound. The same is valid if one replaces the exponential function in the product by functions of the Kato class, that is, by real-valued Borel measurable functions $f(\\cdot)$ defined on the non-negative real axis obeying $0 \\le f(x) \\le 1$, $f(0) = 1$ and $f'(+0) = -1$, with some addition...
International Nuclear Information System (INIS)
Doliwa, A.; Grinevich, P.; Nieszporski, M.; Santini, P. M.
2007-01-01
We present the sublattice approach, a procedure to generate, from a given integrable lattice, a sublattice which inherits its integrability features. We consider, as illustrative example of this approach, the discrete Moutard 4-point equation and its sublattice, the self-adjoint 5-point scheme on the star of the square lattice, which are relevant in the theory of the integrable discrete geometries and in the theory of discrete holomorphic and harmonic functions (in this last context, the discrete Moutard equation is called discrete Cauchy-Riemann equation). Therefore an integrable, at one energy, discretization of elliptic two-dimensional operators is considered. We use the sublattice point of view to derive, from the Darboux transformations and superposition formulas of the discrete Moutard equation, the Darboux transformations and superposition formulas of the self-adjoint 5-point scheme. We also construct, from algebro-geometric solutions of the discrete Moutard equation, algebro-geometric solutions of the self-adjoint 5-point scheme. In particular, we show that the corresponding restrictions on the finite-gap data are of the same type as those for the fixed energy problem for the two-dimensional Schroedinger operator. We finally use these solutions to construct explicit examples of discrete holomorphic and harmonic functions, as well as examples of quadrilateral surfaces in R 3
Self-adjoint Hamiltonians with a mass jump: General matching conditions
International Nuclear Information System (INIS)
Gadella, M.; Kuru, S.; Negro, J.
2007-01-01
The simplest position-dependent mass Hamiltonian in one dimension, where the mass has the form of a step function with a jump discontinuity at one point, is considered. The most general matching conditions at the jumping point for the solutions of the Schroedinger equation that provide a self-adjoint Hamiltonian are characterized
On the buckling of magnetothermoviscoelastic plate and an associated quadratic operator bundle
International Nuclear Information System (INIS)
El-Sayed, M.A.
1987-10-01
The paper is devoted to the application of the theory of quadratic self-adjoint operator bundles to investigate the problem of oscillations and stability of an isotropic homogeneous, thermoviscoelastic ferromagnetic plate of arbitrary shape, small constant thickness and infinite electric conductivity, placed in a transverse uniform constant magnetic field and clamped along its whole boundary. 14 refs
Non-self-adjoint Hamiltonians defined by generalized Riesz bases
Energy Technology Data Exchange (ETDEWEB)
Inoue, H., E-mail: h-inoue@math.kyushu-u.ac.jp [Graduate School of Mathematics, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Takakura, M., E-mail: mayumi@fukuoka-u.ac.jp [Department of Applied Mathematics, Fukuoka University, Fukuoka 814-0180 (Japan)
2016-08-15
Bagarello, Inoue, and Trapani [J. Math. Phys. 55, 033501 (2014)] investigated some operators defined by the Riesz bases. These operators connect with quasi-Hermitian quantum mechanics, and its relatives. In this paper, we introduce a notion of generalized Riesz bases which is a generalization of Riesz bases and investigate some operators defined by the generalized Riesz bases by changing the frameworks of the operators defined in the work of Bagarello, Inoue, and Trapani.
Self-Adjoint Angular Flux Equation for Coupled Electron-Photon Transport
International Nuclear Information System (INIS)
Liscum-Powell, J.L.; Lorence, L.J. Jr.; Morel, J.E.; Prinja, A.K.
1999-01-01
Recently, Morel and McGhee described an alternate second-order form of the transport equation called the self adjoint angular flux (SAAF) equation that has the angular flux as its unknown. The SAAF formulation has all the advantages of the traditional even- and odd-parity self-adjoint equations, with the added advantages that it yields the full angular flux when it is numerically solved, it is significantly easier to implement reflective and reflective-like boundary conditions, and in the appropriate form it can be solved in void regions. The SAAF equation has the disadvantage that the angular domain is the full unit sphere and, like the even- and odd- parity form, S n source iteration cannot be implemented using the standard sweeping algorithm. Also, problems arise in pure scattering media. Morel and McGhee demonstrated the efficacy of the SAAF formulation for neutral particle transport. Here we apply the SAAF formulation to coupled electron-photon transport problems using multigroup cross-sections from the CEPXS code and S n discretization
Self-adjoint angular flux equation for coupled electron-photon transport
International Nuclear Information System (INIS)
Liscum-Powell, J.L.; Prinja, A.K.; Morel, J.E.; Lorence, L.J. Jr.
1999-01-01
Recently, Morel and McGhee described an alternate second-order form of the transport equation called the self-adjoint angular flux (SAAF) equation that has the angular flux as its unknown. The SAAF formulation has all the advantages of the traditional even- and odd-parity self-adjoint equations, with the added advantages that it yields the full angular flux when it is numerically solved, it is significantly easier to implement reflective and reflective-like boundary conditions, and in the appropriate form it can be solved in void regions. The SAAF equation has the disadvantage that the angular domain is the full unit sphere, and, like the even- and odd-parity form, S n source iteration cannot be implemented using the standard sweeping algorithm. Also, problems arise in pure scattering media. Morel and McGhee demonstrated the efficacy of the SAAF formulation for neutral particle transport. Here, the authors apply the SAAF formulation to coupled electron-photon transport problems using multigroup cross sections from the CEPXS code and S n discretization
Self-adjointness of the fast flux in a pressurized water reactor
International Nuclear Information System (INIS)
Mosteller, R.D.
1985-01-01
Most computer codes for the analysis of systems transients rely on a simplified representation of the active core, typically employing either a one-dimensional or a point kinetics model. The collapsing of neutronics data from multidimensional steady-state calculations normally employs flux/flux-adjoint weighting. The multidimensional calculations, however, usually are performed only for the forward problem, not the adjoint. The collapsing methodologies employed in generating the neutronics input for transient codes typically construct adjoint fluxes from the assumption that the fast flux is self-adjoint. Until now, no further verification of this assumption has been undertaken for thermal reactors. As part of the verification effort for EPRI's reactor analysis support package, the validity of this assumption now has been investigated for a modern pressurized water reactor (PWR). The PDQ-7 code was employed to perform two-group fine-mesh forward and adjoint calculations for a two-dimensional representation of Zion Unit 2 at beginning of life, based on the standard PWR ARMP model. It has been verified that the fast flux is very nearly self-adjoint in a PWR. However, a significant error can arise during the subsequent construction of the thermal adjoint flux unless allowance is made for the difference between the forward and adjoint thermal buckling terms. When such a difference is included, the thermal adjoint flux can be estimated very accurately
Quasi-stationary states and fermion pair creation from a vacuum in supercritical Coulomb field
Khalilov, V. R.
2017-12-01
Creation of charged fermion pair from a vacuum in so-called supercritical Coulomb potential is examined for the case when fermions can move only in the same (one) plane. In which case, quantum dynamics of charged massive or massless fermions can be described by the two-dimensional Dirac Hamiltonians with an usual (-a/r) Coulomb potential. These Hamiltonians are singular and require the additional definition in order for them to be treated as self-adjoint quantum-mechanical operators. We construct the self-adjoint two-dimensional Dirac Hamiltonians with a Coulomb potential and determine the quantum-mechanical states for such Hamiltonians in the corresponding Hilbert spaces of square-integrable functions. We determine the scattering amplitude in which the self-adjoint extension parameter is incorporated and then obtain equations implicitly defining possible discrete energy spectra of the self-adjoint Dirac Hamiltonians with a Coulomb potential. It is shown that this quantum system becomes unstable in the presence of a supercritical Coulomb potential which manifests in the appearance of quasi-stationary states in the lower (negative) energy continuum. The energy spectrum of those states is quasi-discrete, consists of broadened levels with widths related to the inverse lifetimes of the quasi-stationary states as well as the probability of creation of charged fermion pair by a supercritical Coulomb field. Explicit analytical expressions for the creation probabilities of charged (massive or massless) fermion pair are obtained in a supercritical Coulomb field.
Time Operator in Relativistic Quantum Mechanics
Khorasani, Sina
2017-07-01
It is first shown that the Dirac’s equation in a relativistic frame could be modified to allow discrete time, in agreement to a recently published upper bound. Next, an exact self-adjoint 4 × 4 relativistic time operator for spin-1/2 particles is found and the time eigenstates for the non-relativistic case are obtained and discussed. Results confirm the quantum mechanical speculation that particles can indeed occupy negative energy levels with vanishingly small but non-zero probablity, contrary to the general expectation from classical physics. Hence, Wolfgang Pauli’s objection regarding the existence of a self-adjoint time operator is fully resolved. It is shown that using the time operator, a bosonic field referred here to as energons may be created, whose number state representations in non-relativistic momentum space can be explicitly found.
Bourne, D.P.; Elman, H.; Osborn, J.E.
2009-01-01
This paper is the second part of a two-part paper treating a non-self-adjoint quadratic eigenvalue problem for the linear stability of solutions to the Taylor-Couette problem for flow of a viscous liquid in a deformable cylinder, with the cylinder modelled as a membrane. The first part formulated
Spectral Solutions of Self-adjoint Elliptic Problems with Immersed Interfaces
International Nuclear Information System (INIS)
Auchmuty, G.; Klouček, P.
2011-01-01
This paper describes a spectral representation of solutions of self-adjoint elliptic problems with immersed interfaces. The interface is assumed to be a simple non-self-intersecting closed curve that obeys some weak regularity conditions. The problem is decomposed into two problems, one with zero interface data and the other with zero exterior boundary data. The problem with zero interface data is solved by standard spectral methods. The problem with non-zero interface data is solved by introducing an interface space H Γ (Ω) and constructing an orthonormal basis of this space. This basis is constructed using a special class of orthogonal eigenfunctions analogously to the methods used for standard trace spaces by Auchmuty (SIAM J. Math. Anal. 38, 894–915, 2006). Analytical and numerical approximations of these eigenfunctions are described and some simulations are presented.
International Nuclear Information System (INIS)
Finn, John M.
2015-01-01
Properties of integration schemes for solenoidal fields in three dimensions are studied, with a focus on integrating magnetic field lines in a plasma using adaptive time stepping. It is shown that implicit midpoint (IM) and a scheme we call three-dimensional leapfrog (LF) can do a good job (in the sense of preserving KAM tori) of integrating fields that are reversible, or (for LF) have a “special divergence-free” (SDF) property. We review the notion of a self-adjoint scheme, showing that such schemes are at least second order accurate and can always be formed by composing an arbitrary scheme with its adjoint. We also review the concept of reversibility, showing that a reversible but not exactly volume-preserving scheme can lead to a fractal invariant measure in a chaotic region, although this property may not often be observable. We also show numerical results indicating that the IM and LF schemes can fail to preserve KAM tori when the reversibility property (and the SDF property for LF) of the field is broken. We discuss extensions to measure preserving flows, the integration of magnetic field lines in a plasma and the integration of rays for several plasma waves. The main new result of this paper relates to non-uniform time stepping for volume-preserving flows. We investigate two potential schemes, both based on the general method of Feng and Shang [Numer. Math. 71, 451 (1995)], in which the flow is integrated in split time steps, each Hamiltonian in two dimensions. The first scheme is an extension of the method of extended phase space, a well-proven method of symplectic integration with non-uniform time steps. This method is found not to work, and an explanation is given. The second method investigated is a method based on transformation to canonical variables for the two split-step Hamiltonian systems. This method, which is related to the method of non-canonical generating functions of Richardson and Finn [Plasma Phys. Controlled Fusion 54, 014004 (2012
Classical limit of a quantum particle in an external Yang-Mills field
International Nuclear Information System (INIS)
Moschella, U.
1989-01-01
It is studied the classical limit of a quantum particle in an external non-abelian gauge field. It is shown that the unitary group describing the quantum fluctuations around any classic phase orbit has a classical limit when h tends to zero under very general conditions on the potentials. It is also proved the self-adjointness of the Hamilton's operator of the quantum theory for a large class of potentials. Some applications of the theory are finally exposed
Sesquilinear forms corresponding to a non-semibounded Sturm-Liouville operator
Fleige, Andreas; Hassi, Seppo; de Snoo, Henk; Winkler, Henrik
2010-01-01
Let - DpD be a differential operator on the compact interval [-b, b] whose leading coefficient is positive on (0, b] and negative on [b,0), with fixed, separated, self-adjoint boundary conditions at h and b and an additional interface condition at 0. The self-adjoint extensions of the corresponding
Dirac-like operators on the Hilbert space of differential forms on manifolds with boundaries
Pérez-Pardo, Juan Manuel
The problem of self-adjoint extensions of Dirac-type operators in manifolds with boundaries is analyzed. The boundaries might be regular or non-regular. The latter situation includes point-like interactions, also called delta-like potentials, in manifolds of dimension higher than one. Self-adjoint boundary conditions for the case of dimension 2 are obtained explicitly.
Kneser-Hecke-operators in coding theory
Nebe, Gabriele
2005-01-01
The Kneser-Hecke-operator is a linear operator defined on the complex vector space spanned by the equivalence classes of a family of self-dual codes of fixed length. It maps a linear self-dual code $C$ over a finite field to the formal sum of the equivalence classes of those self-dual codes that intersect $C$ in a codimension 1 subspace. The eigenspaces of this self-adjoint linear operator may be described in terms of a coding-theory analogue of the Siegel $\\Phi $-operator.
International Nuclear Information System (INIS)
Lyskova, A.S.
1986-01-01
This paper studies the two-dimensional Schrodinger operator H in a periodic magnetic field B(x,y) and in an electric field with periodic potential V(x,y). It is assumed that the functions B(x,y) and V(x,y) are periodic with respect to some lattice in R 2 and that the m agnetic flux through a unit cell is an integral number. The operator H is represented as a direct integral over the two-dimensional torus of the reciprocal lattice of elliptic self-adjoint operators H /sub p1/, /sub p2/ which possess a discrete spectrum lambda /sub j/ (p 1 ,p 2 ), j = 0,1,2.... On the basis of an exactly integrable case - the Schrodinger operator in a constant magnetic field - perturbation theory is used to investigate the typical dispersion laws lambda /sub j/ (p 1 ,p 2 ) and establish their topological characteristics (quantum numbers). A theorem is proved: In the general case, the Schrodinger operator has a coutable number of dispersion laws with arbitrary quantum numbers in no way related to one another or to thflux of the external magnetic field
Energy Technology Data Exchange (ETDEWEB)
Laboure, Vincent M.; Wang, Yaqi; DeHart, Mark D.
2016-05-01
In this paper, we study the Least-Squares (LS) PN form of the transport equation compatible with voids [1] in the context of Continuous Finite Element Methods (CFEM).We first deriveweakly imposed boundary conditions which make the LS weak formulation equivalent to the Self-Adjoint Angular Flux (SAAF) variational formulation with a void treatment [2], in the particular case of constant cross-sections and a uniform mesh. We then implement this method in Rattlesnake with the Multiphysics Object Oriented Simulation Environment (MOOSE) framework [3] using a spherical harmonics (PN) expansion to discretize in angle. We test our implementation using the Method of Manufactured Solutions (MMS) and find the expected convergence behavior both in angle and space. Lastly, we investigate the impact of the global non-conservation of LS by comparing the method with SAAF on a heterogeneous test problem.
Energy Technology Data Exchange (ETDEWEB)
Vincent M. Laboure; Yaqi Wang; Mark D. DeHart
2016-05-01
In this paper, we study the Least-Squares (LS) PN form of the transport equation compatible with voids in the context of Continuous Finite Element Methods (CFEM).We first deriveweakly imposed boundary conditions which make the LS weak formulation equivalent to the Self-Adjoint Angular Flux (SAAF) variational formulation with a void treatment, in the particular case of constant cross-sections and a uniform mesh. We then implement this method in Rattlesnake with the Multiphysics Object Oriented Simulation Environment (MOOSE) framework using a spherical harmonics (PN) expansion to discretize in angle. We test our implementation using the Method of Manufactured Solutions (MMS) and find the expected convergence behavior both in angle and space. Lastly, we investigate the impact of the global non-conservation of LS by comparing the method with SAAF on a heterogeneous test problem.
International Nuclear Information System (INIS)
Ibragimov, N Kh; Avdonina, E D
2013-01-01
The method of nonlinear self-adjointness, which was recently developed by the first author, gives a generalization of Noether's theorem. This new method significantly extends approaches to constructing conservation laws associated with symmetries, since it does not require the existence of a Lagrangian. In particular, it can be applied to any linear equations and any nonlinear equations that possess at least one local conservation law. The present paper provides a brief survey of results on conservation laws which have been obtained by this method and published mostly in recent preprints of the authors, along with a method for constructing exact solutions of systems of partial differential equations with the use of conservation laws. In most cases the solutions obtained by the method of conservation laws cannot be found as invariant or partially invariant solutions. Bibliography: 23 titles
Generalized Polar Decompositions for Closed Operators in Hilbert Spaces and Some Applications
Gesztesy, Fritz; Malamud, Mark; Mitrea, Marius; Naboko, Serguei
2008-01-01
We study generalized polar decompositions of densely defined, closed linear operators in Hilbert spaces and provide some applications to relatively (form) bounded and relatively (form) compact perturbations of self-adjoint, normal, and m-sectorial operators.
Quasi boundary triples and semi-bounded self-adjoint extensions
Czech Academy of Sciences Publication Activity Database
Behrndt, J.; Langer, M.; Lotoreichik, Vladimir; Rohleder, J.
2017-01-01
Roč. 147, č. 5 (2017), s. 895-916 ISSN 0308-2105 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : semi-bounded operator * boundary triple * Weyl function * eliptic differential operator * Dirichlet-Neumann map Subject RIV: BE - Theoretical Physics OBOR OECD: Applied mathematics Impact factor: 1.158, year: 2016
An abstract approach to some spectral problems of direct sum differential operators
Directory of Open Access Journals (Sweden)
Maksim S. Sokolov
2003-07-01
Full Text Available In this paper, we study the common spectral properties of abstract self-adjoint direct sum operators, considered in a direct sum Hilbert space. Applications of such operators arise in the modelling of processes of multi-particle quantum mechanics, quantum field theory and, specifically, in multi-interval boundary problems of differential equations. We show that a direct sum operator does not depend in a straightforward manner on the separate operators involved. That is, on having a set of self-adjoint operators giving a direct sum operator, we show how the spectral representation for this operator depends on the spectral representations for the individual operators (the coordinate operators involved in forming this sum operator. In particular it is shown that this problem is not immediately solved by taking a direct sum of the spectral properties of the coordinate operators. Primarily, these results are to be applied to operators generated by a multi-interval quasi-differential system studied, in the earlier works of Ashurov, Everitt, Gesztezy, Kirsch, Markus and Zettl. The abstract approach in this paper indicates the need for further development of spectral theory for direct sum differential operators.
On commuting operator exponentials, II
Indian Academy of Sciences (India)
where N is an unbounded normal operator and M is a bounded normal operator in the. Hilbert space. Keywords. Self-adjoint and normal operator; commuting normal operator exponent- ials; Borel functional calculus. 1. Introduction. Let E be a complex Hilbert space and let B(E) be the algebra of bounded linear operators.
The class of n-entire operators
International Nuclear Information System (INIS)
Silva, Luis O; Toloza, Julio H
2013-01-01
We introduce a classification of simple, regular, closed symmetric operators with deficiency indices (1, 1) according to a geometric criterion that extends the classical notions of entire operators and entire operators in the generalized sense due to M G Krein. We show that these classes of operators have several distinctive properties, some of them related to the spectra of their canonical self-adjoint extensions. In particular, we provide necessary and sufficient conditions on the spectra of two canonical self-adjoint extensions of an operator for it to belong to one of our classes. Our discussion is based on some recent results in the theory of de Branges spaces. (paper)
Integrated solution for field operations
Energy Technology Data Exchange (ETDEWEB)
Aubin, Renaud; Dionis, Francois [EDF, Chatou (France)
2014-08-15
This document presents our approach to design and to implement mobile applications for field operations. Internal on-field studies yield to the fact that the value added by mobile solutions is correlated with the easiness of their integration with each other and with the underlying information systems. Moreover, the fast-growing mobile market brings new concepts to the mass and industrial applications design can benefit from these. As a consequence, a simple components-based approach has been applied to design and develop mobile applications for field operations and on-site experiments of the resulting applications have been conducted.
Integrated solution for field operations
International Nuclear Information System (INIS)
Aubin, Renaud; Dionis, Francois
2014-01-01
This document presents our approach to design and to implement mobile applications for field operations. Internal on-field studies yield to the fact that the value added by mobile solutions is correlated with the easiness of their integration with each other and with the underlying information systems. Moreover, the fast-growing mobile market brings new concepts to the mass and industrial applications design can benefit from these. As a consequence, a simple components-based approach has been applied to design and develop mobile applications for field operations and on-site experiments of the resulting applications have been conducted
Integrated solution for field operations
International Nuclear Information System (INIS)
Aubin, Renaud; Dionis, Francois
2014-01-01
This paper presents the authors' approach to design and to implement mobile applications for field operations. Internal on-field studies can yield the fact that the value-added by mobile solutions is correlated with the easiness of their integration with each other and with the underlying information systems. Moreover, the fast-growing mobile market brings new concepts to the mass and industrial applications design can benefit from these. As a consequence, a simple components-based approach has been applied to design and develop mobile applications for field operations and on-site experiments of the resulting applications have been conducted. (author)
Introduction to operator space theory
Pisier, Gilles
2003-01-01
An introduction to the theory of operator spaces, emphasising examples that illustrate the theory and applications to C*-algebras, and applications to non self-adjoint operator algebras, and similarity problems. Postgraduate and professional mathematicians interested in functional analysis, operator algebras and theoretical physics will find the book has much to offer.
Organization for field operator training
International Nuclear Information System (INIS)
Boizet, F.; Dejou, P.
1996-01-01
Organization for field operator training is described, dealing with 4 strong ambitions: deliberate policy of encouraging the staff to accept greater personal responsibilities; on shift and off shift support to allow this acceptation; continuous enhancement of individual and team professionalism; reinforcement of the management
Vertex operators and Jordan fields
International Nuclear Information System (INIS)
Ferreira, L.A.; Gomes, J.F.; Zimerman, A.H.
1988-01-01
The construction of Lie algebras in terms of Jordan algebras generators is discussed. The key to the construction is the triality relation already incorporated into matrix products. A generalisation to Kac-Moody algebras in terms of vertex operators is proposed and may provide a clue for the construction of new representations of Kac-Moody algebras in terms of Jordan fields. (author) [pt
Scalar field dynamics in a BTZ background with generic boundary conditions
Energy Technology Data Exchange (ETDEWEB)
Garbarz, Alan; La Madrid, Joan [UBA y IFIBA, CONICET, Departamento de Fisica, FCEyN, Buenos Aires (Argentina); Leston, Mauricio [Pabellon IAFE-CONICET, Instituto de Astronomia y Fisica del Espacio, Buenos Aires (Argentina)
2017-11-15
We revisit the dynamics of a massive scalar field in a Banados, Teitelboim, and Zanelli background taking into account the lack of global hyperbolicity of the spacetime. We approach this issue using the strategy of Ishibashi and Wald which finds a unique smooth solution as the causal evolution of initial data, each possible evolution corresponding to a positive self-adjoint extension of certain operator in a Hilbert space on the initial surface. Moreover, solutions obtained this way are the most general ones satisfying a few physically sensible requirements. This procedure is intimately related to the choice of boundary conditions and the existence of bound states. We find that the scalar field dynamics in the (effective) mass window -3/4 ≤ m{sub e}{sup 2}l{sup 2} < 0 can be well defined within a one-parametric family of distinct boundary conditions (-3/4 being the conformally coupled case), while for m{sub e}{sup 2}l{sup 2} ≥ 0 the boundary condition is unique (only one self-adjoint extension is possible). It is argued that there is no sensible evolution possible for m{sub e}{sup 2}l{sup 2} < -1, and also it is shown that in the range m{sub e}{sup 2}l{sup 2} element of [-1, -3/4) there is a U(1) family of allowed boundary conditions, however, the positivity of the self-adjoint extensions is only motivated but not proven. We focus mainly on describing the dynamics of such evolutions given the initial data and all possible boundary conditions, and in particular we show the energy is always positive and conserved. (orig.)
Theoretical foundations of functional data analysis, with an introduction to linear operators
Hsing, Tailen
2015-01-01
Theoretical Foundations of Functional Data Analysis, with an Introduction to Linear Operators provides a uniquely broad compendium of the key mathematical concepts and results that are relevant for the theoretical development of functional data analysis (FDA).The self-contained treatment of selected topics of functional analysis and operator theory includes reproducing kernel Hilbert spaces, singular value decomposition of compact operators on Hilbert spaces and perturbation theory for both self-adjoint and non self-adjoint operators. The probabilistic foundation for FDA is described from the
Exact solution for a quantum field with δ-like interaction: effective action and UV renormalization
International Nuclear Information System (INIS)
Solodukhin, Sergey N.
1999-01-01
A quantum field described by the field operator Δ a = Δ + aδ Σ involving a δ-like potential concentrated on a subspace Σ is considered. Mathematically, the treatment of the δ-potential is based on the theory of self-adjoint extension of the unperturbed operator Δ. We give the general expressions for the resolvent and the heat kernel of the perturbed operator Δ a . The main attention is paid to d = 2 δ-potential though d = 1 and d = 3 cases are considered in some detail. We calculate exactly the heat kernel, Green's functions and the effective action for the operator Δ a in diverse dimensions and for various spaces Σ. The renormalization phenomenon for the coupling constant a of d = 2 and d = 3 δ-potentials is observed. We find the non-perturbative behavior of the effective action with respect to the renormalized coupling a ren
Model improves oil field operating cost estimates
International Nuclear Information System (INIS)
Glaeser, J.L.
1996-01-01
A detailed operating cost model that forecasts operating cost profiles toward the end of a field's life should be constructed for testing depletion strategies and plans for major oil fields. Developing a good understanding of future operating cost trends is important. Incorrectly forecasting the trend can result in bad decision making regarding investments and reservoir operating strategies. Recent projects show that significant operating expense reductions can be made in the latter stages o field depletion without significantly reducing the expected ultimate recoverable reserves. Predicting future operating cost trends is especially important for operators who are currently producing a field and must forecast the economic limit of the property. For reasons presented in this article, it is usually not correct to either assume that operating expense stays fixed in dollar terms throughout the lifetime of a field, nor is it correct to assume that operating costs stay fixed on a dollar per barrel basis
Conformal invariant quantum field theory and composite field operators
International Nuclear Information System (INIS)
Kurak, V.
1976-01-01
The present status of conformal invariance in quantum field theory is reviewed from a non group theoretical point of view. Composite field operators dimensions are computed in some simple models and related to conformal symmetry
On the spectrum of a periodic operator with a small localized perturbation
International Nuclear Information System (INIS)
Borisov, D I; Gadyl'shin, R R
2008-01-01
The paper deals with the spectrum of a periodic self-adjoint differential operator on the real axis perturbed by a small localized non-self-adjoint operator. We show that the continuous spectrum does not depend on the perturbation, the residual spectrum is empty, and the point spectrum has no finite accumulation points. We study the problem of the existence of eigenvalues embedded in the continuous spectrum, obtain necessary and sufficient conditions for the existence of eigenvalues, construct asymptotic expansions of the eigenvalues and corresponding eigenfunctions and consider some examples
Operating costs on Norwegian fields
International Nuclear Information System (INIS)
Sunnevaag, K.; Nansve, A.H.
1992-09-01
In this report we summarize some of the findings in a project for A/S Norske Shell, where the objective was to find trends in the development of operating expenditures on the Norwegian Continental Shelf if any, and to explain these. We also present a short compilation of articles on the subject. 23 refs., 13 figs
Linear spin-zero quantum fields in external gravitational and scalar fields
International Nuclear Information System (INIS)
Kay, B.S.
1977-10-01
Mathematically rigorous results are given on the quantization of the covariant Klein-Gordon field with an external stationary scalar interaction in a stationary curved space-time. It is shown how, following Segal, Weinless etc., the problem reduces to finding a ''one-particle structure'' for the corresponding classical system. The main result is an existence theorem for such a one-particle structure for a precisely specified class of stationary space-times. Byproducts of our approach are (1)a discussion of when the equal-time hypersurfaces in a given stationary space-time are Cauchy; (2)a proof that when a one-particle structure exists it is unique a result of general interest for the quantization of linear systems; (3)a modification and extension of the methods of Chernoff [3] for proving the essential self-adjointness of ceratin partial differential operators
Energy Technology Data Exchange (ETDEWEB)
Benci, V; Fortunato, D [Istituto di Matematica Applicata, Bari (Italy)
1981-04-21
Some self-adjoint operators, which are the Friedrichs realization in L/sup 2/ of a class of nonelliptic differential operators, are shown to have a positive, discrete spectrum. The results obtained are applied to study operators which occur in the dynamical description of some elementary particles.
International Nuclear Information System (INIS)
Nazarov, S A
1999-01-01
We describe a wide class of boundary-value problems for which the application of elliptic theory can be reduced to elementary algebraic operations and which is characterized by the following polynomial property: the sesquilinear form corresponding to the problem degenerates only on some finite-dimensional linear space P of vector polynomials. Under this condition the boundary-value problem is elliptic, and its kernel and cokernel can be expressed in terms of P. For domains with piecewise-smooth boundary or infinite ends (conic, cylindrical, or periodic), we also present fragments of asymptotic formulae for the solutions, give specific versions of general conditional theorems on the Fredholm property (in particular, by modifying the ordinary weighted norms), and compute the index of the operator corresponding to the boundary-value problem. The polynomial property is also helpful for asymptotic analysis of boundary-value problems in thin domains and junctions of such domains. Namely, simple manipulations with P permit one to find the size of the system obtained by dimension reduction as well as the orders of the differential operators occurring in that system and provide complete information on the boundary layer structure. The results are illustrated by examples from elasticity and hydromechanics
Biorthogonal vectors, sesquilinear forms, and some physical operators
Bagarello, F.; Inoue, H.; Trapani, C.
2018-03-01
Continuing the analysis undertaken in previous articles, we discuss some features of non-self-adjoint operators and sesquilinear forms which are defined starting from two biorthogonal families of vectors, like the so-called generalized Riesz systems, enjoying certain properties. In particular, we discuss what happens when they forms two D -quasi-bases.
Vortex operators in gauge field theories
International Nuclear Information System (INIS)
Polchinski, J.
1980-07-01
Several related aspects of the 't Hooft vortex operator are studied. The current picture of the vacuum of quantum chromodynamics, the idea of dual field theories, and the idea of the vortex operator are reviewed first. The Abelian vortex operator written in terms of elementary fields and the calculation of its Green's functions are considered. A two-dimensional solvable model of a Dirac string is presented. The expression of the Green's functions more neatly in terms of Wu and Yang's geometrical idea of sections is addressed. The renormalization of the Green's functions of two kinds of Abelian looplike operators, the Wilson loop and the vortex operator, is studied; for both operators only an overall multiplicative renormalization is needed. In the case of the vortex this involves a surprising cancellation. Next, the dependence of the Green's functions of the Wilson and 't Hooft operators on the nature of the vacuum is discussed. The cluster properties of the Green's functions are emphasized. It is seen that the vortex operator in a massive Abelian theory always has surface-like clustering. The form of Green's functions in terms of Feynman graphs is the same in Higgs and symmetric phases; the difference appears in the sum over all tadpole trees. Finally, systems having fields in the fundamental representation are considered. When these fields enter only weakly into the dynamics, a vortex-like operator is anticipated. Any such operator can no longer be local looplike, but must have commutators at long range. A U(1) lattice gauge theory with two matter fields, one singly charged (fundamental) and one doubly charged (adjoint), is examined. When the fundamental field is weakly coupled, the expected phase transitions are found. When it is strongly coupled, the operator still appears to be a good order parameter, a discontinuous change in its behavior leads to a new phase transition. 18 figures
Vector fields and differential operators: noncommutative case
International Nuclear Information System (INIS)
Borowiec, A.
1997-01-01
A notion of Cartan pairs as an analogy of vector fields in the realm of noncommutative geometry has been proposed previously. In this paper an outline is given of the construction of a noncommutative analogy of the algebra of differential operators as well as its (algebraic) Fock space realization. Co-universal vector fields and covariant derivatives will also be discussed
Constructing quantum fields in a Fock space using a new picture of quantum mechanics
International Nuclear Information System (INIS)
Farrukh, M.O.
1977-11-01
For any conventional non-relativistic quantum theory of a finite number of degrees of freedom a picture is constructed called '' the scattering picture'', combining the ''nice'' properties of both the interaction and the Heisenberg pictures, and show that in the absence of bound states, the theory could be formulated in terms of a free Hamiltonian and an effective potential. The equations thus derived are generalized to the relativistic case and show that, given a Poincare invariant self-adjoint operator D densely defined on a Fock space, there exists an interacting field which is asymptotically free and has as the scattering matrix the non-trivial operator S=esup(iD), provided that D annihilates the vacuum and the one-particle states. Crossing relations could easily be imposed on D, but apart from a few comments, the problem of analyticity of S is left open
Vortex operators in gauge field theories
International Nuclear Information System (INIS)
Polchinski, J.G.
1980-01-01
We study several related aspects of the t Hooft vortex operator. The first chapter reviews the current picture of the vacuum of quantum chromodynamics, the idea of dual field theories, and the idea of the vortex operator. The second chapter deals with the Abelian vortex operator written in terms of elementary fields and with the calculation of its Green's functions. The Dirac veto problem appears in a new guise. We present a two dimensional solvable model of a Dirac string. This leads us to a new solution of the veto problem; we discuss its extension to four dimensions. We then show how the Green's functions can be expressed more neatly in terms of Wu and Yang's geometrical idea of sections. In the third chapter we discuss the dependence of the Green's functions of the Wilson and t Hooft operators on the nature of the vacuum. In the fourth chapter we consider systems which have fields in the fundamental representation, so that there are no vortex operators. When these fields enter only weakly into the dynamics, as is the case in QCD and in real superconductors, we would expect to be able to define a vortex-like operator. We show that any such operator can no longer be local looplike, but must have commutators at long range. We can still find an operator with useful properties, its cluster property, though more complicated than that of the usual vortex operator, still appears to distinguish Higgs, confining and perturbative phases. To test this, we consider a U(1) lattice gauge theory with two matter fields, one singly charged (fundamental) and one doubly charged (adjoint)
On Painleve VI transcendents related to the Dirac operator on the hyperbolic disk
International Nuclear Information System (INIS)
Lisovyy, O.
2008-01-01
Dirac Hamiltonian on the Poincare disk in the presence of an Aharonov-Bohm flux and a uniform magnetic field admits a one-parameter family of self-adjoint extensions. We determine the spectrum and calculate the resolvent for each element of this family. Explicit expressions for Green's functions are then used to find Fredholm determinant representations for the tau function of the Dirac operator with two branch points on the Poincare disk. Isomonodromic deformation theory for the Dirac equation relates this tau function to a one-parameter class of solutions of the Painleve VI equation with γ=0. We analyze long-distance behavior of the tau function, as well as the asymptotics of the corresponding Painleve VI transcendents as s→1. Considering the limit of flat space, we also obtain a class of solutions of the Painleve V equation with β=0
Non-accretive Schrodinger operators and exponential decay of their eigenfunctions
Czech Academy of Sciences Publication Activity Database
Krejčiřík, David; Raymond, N.; Royer, J.; Siegl, Petr
2017-01-01
Roč. 221, č. 2 (2017), s. 779-802 ISSN 0021-2172 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : non-self-adjoint electromagnetic Schrodinger operators * Dirichlet realisation * Agmon-type exponential decay Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.796, year: 2016
International Nuclear Information System (INIS)
Cuesta, Vladimir; Vergara, Jose David; Montesinos, Merced
2011-01-01
We work with gauge systems and using gauge invariant functions we study its quantum counterpart and we find if all these operators are self adjoint or not. Our study is divided in two cases, when we choose clock or clocks that its Poisson brackets with the set of constraints is one or it is different to one. We show some transition amplitudes.
Semiclassical Weyl Formula for a Class of Weakly Regular Elliptic Operators
Energy Technology Data Exchange (ETDEWEB)
Zielinski, Lech [Universite du Littoral, LMPA, Centre Mi-Voix (France)], E-mail: Lech.Zielinski@lmpa.univ-littoral.fr
2006-02-15
We investigate the semiclassical Weyl formula describing the asymptotic behaviour of the counting function for the number of eigenvalues in the case of self-adjoint elliptic differential operators satisfying weak regularity hypotheses. We consider symbols with possible critical points and with coefficients which have Hoelder continuous derivatives of first order.
Spectral analysis of the diffusion operator with random jumps from the boundary
Czech Academy of Sciences Publication Activity Database
Kolb, M.; Krejčiřík, David
2016-01-01
Roč. 284, 3-4 (2016), s. 877-900 ISSN 0025-5874 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : self-adjoint operators * eigenvalues * eigenfunctions Subject RIV: BE - Theoretical Physics Impact factor: 0.738, year: 2016
Semiclassical Weyl Formula for a Class of Weakly Regular Elliptic Operators
International Nuclear Information System (INIS)
Zielinski, Lech
2006-01-01
We investigate the semiclassical Weyl formula describing the asymptotic behaviour of the counting function for the number of eigenvalues in the case of self-adjoint elliptic differential operators satisfying weak regularity hypotheses. We consider symbols with possible critical points and with coefficients which have Hoelder continuous derivatives of first order
Dirac equation in magnetic-solenoid field
Energy Technology Data Exchange (ETDEWEB)
Gavrilov, S.P. [Dept. Fisica e Quimica, UNESP, Campus de Guaratingueta (Brazil); Gitman, D.M.; Smirnov, A.A. [Instituto de Fisica, Universidade de Sao Paulo (Brazil)
2004-07-01
We consider the Dirac equation in the magnetic-solenoid field (the field of a solenoid and a collinear uniform magnetic field). For the case of Aharonov-Bohm solenoid, we construct self-adjoint extensions of the Dirac Hamiltonian using von Neumann's theory of deficiency indices. We find self-adjoint extensions of the Dirac Hamiltonian and boundary conditions at the AB solenoid. Besides, for the first time, solutions of the Dirac equation in the magnetic-solenoid field with a finite radius solenoid were found. We study the structure of these solutions and their dependence on the behavior of the magnetic field inside the solenoid. Then we exploit the latter solutions to specify boundary conditions for the magnetic-solenoid field with Aharonov-Bohm solenoid. (orig.)
International co-operation in the field of operational safety
International Nuclear Information System (INIS)
Dupuis, M.C.
1988-10-01
Operational safety in nuclear power plants is without doubt a field where international co-operation is in constant progress. Accounting for over 80 per cent of the 400 reactors in service throughout the world, the menber countries of the OECD Nuclear Energy Agency (NEA) are constantly striving to improve the exchange and use of the wealth of information to be gained not just from power plant accidents and incidents but from the routine operation of these facilities. The Committee on the Safety of Nuclear Installations (CSNI) helps the Steering Committee for Nuclear Energy to meet the NEA's objectives in the safety field, namely: - to promote co-operation between the safety bodies of member countries - to contribute to the safety and regulation of nuclear activities. The CSNI relies on the technical back-up of several different working groups made up of experts appointed by the member countries. For the past three years I have had the honour of chairing Principal Working Group 1 (PWG 1), which deals with operating experience and human factor. It is in this capacity that I will attempt to outline the group's various activities and its findings illustrated by a few examples
A guide to safe field operations
Yobbi, D.K.; Yorke, T.H.; Mycyk, R.T.
1996-01-01
Most functions of the U.S. Geological Survey (USGS), Water Resources Division (WRD) require employees to participate in numerous field activities ranging from routine meetings with cooperators, other federal and public officials, and private citizens to potentially hazardous assignments, such as making flood measurements and scuba diving to service underwater instruments. It is paramount that each employee be aware of safety procedures and operational policies of the WRD to ensure that (1) their activities avoid or minimize personal injury to the employee, coworkers, or anyone in the vicinity of the field activity, and (2) their conduct does not infringe on the personal or property rights of any individual or organization. The purpose of the guide is to familiarize employees with the operational and safety procedures expected to be followed by each employee as a representative of the WRD. It is also intended as a training tool for all new employees and a document to be reviewed by each employee before undertaking a field assignment. It includes general procedures that are standard and applicable to all field operations, such as communication, vehicle operation, and adequate preparation for anticipated weather conditions. It also includes a discussion of specific procedures and safety considerations for most of the routine field assignments undertaken by hydrologists and hydrologic technicians of the WRD. The guide is not intended to be a technical handbook outlining step-by-step procedures for performing specific tasks or a comprehensive discussion of every possible activity that may be undertaken by a USGS employee. Employees are referred to the Techniques for Water-Resources Investigations (TWRI) series for specific technical procedures and to the U.S. Geological Survey Safety and Environmental Health Handbook 445-1-H (USGS, August 1989), USGS Occupational Hazards and Safety Procedures Handbook 445-2-H (December 1993), the WRD notebook on Safety Policy and
Theory of linear operators in Hilbert space
Akhiezer, N I
1993-01-01
This classic textbook by two mathematicians from the USSR's prestigious Kharkov Mathematics Institute introduces linear operators in Hilbert space, and presents in detail the geometry of Hilbert space and the spectral theory of unitary and self-adjoint operators. It is directed to students at graduate and advanced undergraduate levels, but because of the exceptional clarity of its theoretical presentation and the inclusion of results obtained by Soviet mathematicians, it should prove invaluable for every mathematician and physicist. 1961, 1963 edition.
Operator algebras and conformal field theory
International Nuclear Information System (INIS)
Gabbiani, F.; Froehlich, J.
1993-01-01
We define and study two-dimensional, chiral conformal field theory by the methods of algebraic field theory. We start by characterizing the vacuum sectors of such theories and show that, under very general hypotheses, their algebras of local observables are isomorphic to the unique hyperfinite type III 1 factor. The conformal net determined by the algebras of local observables is proven to satisfy Haag duality. The representation of the Moebius group (and presumably of the entire Virasoro algebra) on the vacuum sector of a conformal field theory is uniquely determined by the Tomita-Takesaki modular operators associated with its vacuum state and its conformal net. We then develop the theory of Mebius covariant representations of a conformal net, using methods of Doplicher, Haag and Roberts. We apply our results to the representation theory of loop groups. Our analysis is motivated by the desire to find a 'background-independent' formulation of conformal field theories. (orig.)
Super high field ohmically heated tokamak operation
International Nuclear Information System (INIS)
Cohn, D.R.; Bromberg, L.; Leclaire, R.J.; Potok, R.E.; Jassby, D.L.
1986-01-01
The authors discuss a super high field mode of tokamak operation that uses ohmic heating or near ohmic heating to ignition. The super high field mode of operation uses very high values of Β/sup 2/α, where Β is the magnetic field and a is the minor radius (Β/sup 2/α > 100 T/sup 2/m). We analyze copper magnet devices with major radii from 1.7 to 3.0 meters. Minimizing or eliminating the need for auxiliary heating has the potential advantages of reducing uncertainty in extrapolating the energy confinement time of current tokamak devices, and reducing engineering problems associated with large auxiliary heating requirements. It may be possible to heat relatively short pulse, inertially cooled tokamaks to ignition with ohmic power alone. However, there may be advantages in using a very small amount of auxiliary power (less than the ohmic heating power) to boost the ohmic heating and provide a faster start-up, expecially in relatively compact devices
Time Operators and Time Crystals
Nakatsugawa, K.; Fujii, T.; Saxena, A.; Tanda, S.
2017-01-01
We investigate time operators in the context of quantum time crystals in ring systems. We demonstrate that a self-adjoint time operator with a periodic time evolution can be derived for a free particle on a ring system: The conventional Aharonov-Bohm time operator is obtained by taking the infinite-radius limit. We also reveal the relationship between our time operator and a $\\mathcal PT$-symmetric time operator. We find that both time operators indeed describe the periodic time evolution of ...
Structure of Hilbert space operators
Jiang, Chunlan
2006-01-01
This book exposes the internal structure of non-self-adjoint operators acting on complex separable infinite dimensional Hilbert space, by analyzing and studying the commutant of operators. A unique presentation of the theorem of Cowen-Douglas operators is given. The authors take the strongly irreducible operator as a basic model, and find complete similarity invariants of Cowen-Douglas operators by using K -theory, complex geometry and operator algebra tools. Sample Chapter(s). Chapter 1: Background (153 KB). Contents: Jordan Standard Theorem and K 0 -Group; Approximate Jordan Theorem of Opera
Summary of field operations, well TRN-1
International Nuclear Information System (INIS)
Fritts, J.E.; Thomas, E.; McCord, J.P.
1996-03-01
TRN-1 was drilled near the SE corner of Kirtland Air Force Base to a depth of 510 feet. This well is in the Site-Wide Hydrogeologic Characterization task field program, which is part of Sandia's Environmental Restoration Project. After drilling, the borehole was logged, plugged to a depth of 352 ft, and completed as a monitoring well. Sand pack interval is from 305 to 352 ft and the screen interval is from 320 to 340 ft. During field operations, important subsurface geologic and hydrologic data were obtained (drill cuttings, geophysical logs of alluvial cover). Identification of the Abo formation in the subsurface will be useful. The subsurface hydrologic data will help define the local hydrostratigraphic framework within the bedrock. Future aquifer testing will be conducted for transmissivity, etc
Some remarks on quasi-Hermitian operators
Energy Technology Data Exchange (ETDEWEB)
Antoine, Jean-Pierre, E-mail: jean-pierre.antoine@uclouvain.be [Institut de Recherche en Mathématique et Physique, Université Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Trapani, Camillo, E-mail: camillo.trapani@unipa.it [Dipartimento di Matematica e Informatica, Università di Palermo, I-90123, Palermo (Italy)
2014-01-15
A quasi-Hermitian operator is an operator that is similar to its adjoint in some sense, via a metric operator, i.e., a strictly positive self-adjoint operator. Whereas those metric operators are in general assumed to be bounded, we analyze the structure generated by unbounded metric operators in a Hilbert space. Following our previous work, we introduce several generalizations of the notion of similarity between operators. Then we explore systematically the various types of quasi-Hermitian operators, bounded or not. Finally, we discuss their application in the so-called pseudo-Hermitian quantum mechanics.
Field operational tests of Smartway in Japan
Directory of Open Access Journals (Sweden)
Fumihiko Kanazawa
2010-07-01
Full Text Available Efforts are underway in Japan to promote “Smartway” next-generation roadways, which provide a variety of services through the use of advanced ITS technologies. In recent years, the National Institute for Land and Infrastructure Management (NILIM, part of the Ministry of Land, Infrastructure, Transport and Tourism (MLIT, has conducted public–private joint research on next-generation road services using ITS technologies. Field operational tests (FOTs of services including forward obstacle information provision and merging assistance using 5.8 GHz dedicated short range communication (DSRC were conducted on the Tokyo Metropolitan Expressway through FY2007. In FY2008–2009, FOTs were conducted in three major metropolitan areas—Tokyo, Nagoya, and Keihanshin (Kyoto, Osaka, and Kobe—to promote future deployment nationwide. These included tests of information provision services to alert drivers to forward obstacles hidden beyond the crest of an incline and prevent excessive speed on sharp curves. This paper presents an overview of these FOTs conducted by NILIM in recent years and their results.
Spectral function for a nonsymmetric differential operator on the half line
Directory of Open Access Journals (Sweden)
Wuqing Ning
2017-05-01
Full Text Available In this article we study the spectral function for a nonsymmetric differential operator on the half line. Two cases of the coefficient matrix are considered, and for each case we prove by Marchenko's method that, to the boundary value problem, there corresponds a spectral function related to which a Marchenko-Parseval equality and an expansion formula are established. Our results extend the classical spectral theory for self-adjoint Sturm-Liouville operators and Dirac operators.
Stability of ideal MHD configurations. I. Realizing the generality of the G operator
Keppens, R.; Demaerel, T.
2016-12-01
A field theoretical approach, applied to the time-reversible system described by the ideal magnetohydrodynamic (MHD) equations, exposes the full generality of MHD spectral theory. MHD spectral theory, which classified waves and instabilities of static or stationary, usually axisymmetric or translationally symmetric configurations, actually governs the stability of flowing, (self-)gravitating, single fluid descriptions of nonlinear, time-dependent idealized plasmas, and this at any time during their nonlinear evolution. At the core of this theory is a self-adjoint operator G , discovered by Frieman and Rotenberg [Rev. Mod. Phys. 32, 898 (1960)] in its application to stationary (i.e., time-independent) plasma states. This Frieman-Rotenberg operator dictates the acceleration identified by a Lagrangian displacement field ξ , which connects two ideal MHD states in four-dimensional space-time that share initial conditions for density, entropy, and magnetic field. The governing equation reads /d 2 ξ d t 2 = G [ ξ ] , as first noted by Cotsaftis and Newcomb [Nucl. Fusion, Suppl. Part 2, 447 and 451 (1962)]. The time derivatives at left are to be taken in the Lagrangian way, i.e., moving with the flow v. Physically realizable displacements must have finite energy, corresponding to being square integrable in the Hilbert space of displacements equipped with an inner product rule, for which the G operator is self-adjoint. The acceleration in the left-hand side features the Doppler-Coriolis operator v . ∇ , which is known to become an antisymmetric operator when restricting attention to stationary equilibria. Here, we present all derivations needed to get to these insights and connect results throughout the literature. A first illustration elucidates what can happen when self-gravity is incorporated and presents aspects that have been overlooked even in simple uniform media. Ideal MHD flows, as well as Euler flows, have essentially 6 + 1 wave types, where the 6 wave modes
Vertex operator algebras and conformal field theory
International Nuclear Information System (INIS)
Huang, Y.Z.
1992-01-01
This paper discusses conformal field theory, an important physical theory, describing both two-dimensional critical phenomena in condensed matter physics and classical motions of strings in string theory. The study of conformal field theory will deepen the understanding of these theories and will help to understand string theory conceptually. Besides its importance in physics, the beautiful and rich mathematical structure of conformal field theory has interested many mathematicians. New relations between different branches of mathematics, such as representations of infinite-dimensional Lie algebras and Lie groups, Riemann surfaces and algebraic curves, the Monster sporadic group, modular functions and modular forms, elliptic genera and elliptic cohomology, Calabi-Yau manifolds, tensor categories, and knot theory, are revealed in the study of conformal field theory. It is therefore believed that the study of the mathematics involved in conformal field theory will ultimately lead to new mathematical structures which would be important to both mathematics and physics
Sharp Spectral Asymptotics and Weyl Formula for Elliptic Operators with Non-smooth Coefficients
Energy Technology Data Exchange (ETDEWEB)
Zielinski, Lech [Universite Paris 7 (D. Diderot), Institut de Mathematiques de Paris-Jussieu UMR9994 (France)
1999-09-15
The aim of this paper is to give the Weyl formula for eigenvalues of self-adjoint elliptic operators, assuming that first-order derivatives of the coefficients are Lipschitz continuous. The approach is based on the asymptotic formula of Hoermander''s type for the spectral function of pseudo differential operators having Lipschitz continuous Hamiltonian flow and obtained via a regularization procedure of nonsmooth coefficients.
Sharp Spectral Asymptotics and Weyl Formula for Elliptic Operators with Non-smooth Coefficients
International Nuclear Information System (INIS)
Zielinski, Lech
1999-01-01
The aim of this paper is to give the Weyl formula for eigenvalues of self-adjoint elliptic operators, assuming that first-order derivatives of the coefficients are Lipschitz continuous. The approach is based on the asymptotic formula of Hoermander''s type for the spectral function of pseudo differential operators having Lipschitz continuous Hamiltonian flow and obtained via a regularization procedure of nonsmooth coefficients
Management of Tattoos in the Operative Field
Smit, Jeroen M.; Scheele, Karin; Lapid, Oren; Hoogbergen, Maarten M.
2010-01-01
Tattooing is increasingly common in Western society. The aim of the study was to create an overview of the surgical options when a tattoo is present in the operative site and to present an algorithm for the surgical plan. A literature-based study was conducted, using the Pubmed database. The
International Nuclear Information System (INIS)
Ziqi Sun
1993-01-01
During the past few years a considerable interest has been focused on the inverse boundary value problem for the Schroedinger operator with a scalar (electric) potential. The popularity gained by this subject seems to be due to its connection with the inverse scattering problem at fixed energy, the inverse conductivity problem and other important inverse problems. This paper deals with an inverse boundary value problem for the Schroedinger operator with vector (electric and magnetic) potentials. As in the case of the scalar potential, results of this study would have immediate consequences in the inverse scattering problem for magnetic field at fixed energy. On the other hand, inverse boundary value problems for elliptic operators are of independent interest. The study is partly devoted to the understanding of the inverse boundary value problem for a class of general elliptic operator of second order. Note that a self-adjoint elliptic operator of second order with Δ as its principal symbol can always be written as a Schroedinger operator with vector potentials
On the spectrum of elementary type operator
International Nuclear Information System (INIS)
Khan, G.A.; Kyle, J.
1990-11-01
Let H be a complex separable Hilbert space and let B(H) be the algebra of all bounded linear operators on H. Let {A 1 ,...,A n } and {B 1 ,...,B n } be two commuting families of self-adjoint operators in B(H). In this paper we are concerned with the investigation of the spectrum of the elementary type operator Γ : B(H) → B(H) defined by Γ(X) = Σ n i=1 A i XB i for all X in B(H). 8 refs
Spectral Theory for Schrodinger Operators with delta-Interactions Supported on Curves in R-3
Czech Academy of Sciences Publication Activity Database
Behrndt, J.; Frank, R. L.; Kuhn, C.; Lotoreichik, Vladimir; Rohleder, J.
2017-01-01
Roč. 18, č. 4 (2017), s. 1305-1347 ISSN 1424-0637 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : spectral theory * scattering theory * self-adjoint Schrodinger operators Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 1.599, year: 2016
On the spectral properties of Dirac operators with electrostatic delta-shell interactions
Czech Academy of Sciences Publication Activity Database
Behrndt, J.; Exner, Pavel; Holzmann, M.; Lotoreichik, Vladimir
2018-01-01
Roč. 111, č. 3 (2018), s. 47-78 ISSN 0021-7824 R&D Projects: GA ČR(CZ) GA14-06818S Institutional support: RVO:61389005 Keywords : Dirac operator * self-adjoint extension * shell interaction * spectral properties Subject RIV: BE - Theoretical Physics OBOR OECD: Atomic, molecular and chemical physics (physics of atoms and molecules including collision, interaction with radiation, magnetic resonances, Mössbauer effect) Impact factor: 1.802, year: 2016
One-dimensional Schroedinger operators with interactions singular on a discrete set
International Nuclear Information System (INIS)
Gesztesy, F.; Kirsch, W.
We study the self-adjointness of Schroedinger operators -d 2 /dx 2 +V(x) on an arbitrary interval, (a,b) with V(x) locally integrable on (a,b)inverse slantX where X is a discrete set. The treatment of quantum mechanical systems describing point interactions or periodic (possibly strongly singular) potentials is thereby included and explicit examples are presented. (orig.)
Unusual poles of the {zeta}-functions for some regular singular differential operators
Energy Technology Data Exchange (ETDEWEB)
Falomir, H [IFLP, Departamento de Fisica-Facultad de Ciencias Exactas, UNLP, CC 67 (1900) La Plata (Argentina); Muschietti, M A [Departamento de Matematica-Facultad de Ciencias Exactas, UNLP, CC 172 (1900) La Plata (Argentina); Pisani, P A G [IFLP, Departamento de Fisica-Facultad de Ciencias Exactas, UNLP, CC 67 (1900) La Plata (Argentina); Seeley, R [University of Massachusetts at Boston, Boston, MA 02125 (United States)
2003-10-03
We consider the resolvent of a system of first-order differential operators with a regular singularity, admitting a family of self-adjoint extensions. We find that the asymptotic expansion for the resolvent in the general case presents powers of {lambda} which depend on the singularity, and can take even irrational values. The consequences for the pole structure of the corresponding {zeta}- and {eta}-functions are also discussed.
Operational experience gained from the Central Brae subsea field
International Nuclear Information System (INIS)
Sapp, S.J.; Gomersall, S.D.
1994-01-01
The size of the field discoveries made in the North Sea in recent years has declined dramatically. With the low oil price many small fields are not viable stand alone developments. The North Sea has a large, well developed infrastructure of production facilities and pipelines. With many platforms now operating below optimum production rate, subsea tieback of these small fields utilizing the available processing capacity is the most economically attractive means of development. This paper presents a history of such a field development. The Central Brae field is located within the Brae complex of fields, 155 miles north east of Aberdeen, and has been developed by means of a subsea facility tied back to the Brae Alpha platform. A great deal of experience has been gained through the field development, not only in subsea operations but also in completion and template design and operating philosophy
SMART operational field test evaluation : dispatchers survey report : final report
1997-06-01
The Suburban Mobility Authority for Regional Transportation (SMART) has installed an automaticscheduling and dispatch system (ASD) in Southeast Michigan in accordance with their plans toimplement ITS as a site for an operational field test. The purpo...
SMART operational field test evaluation : scheduler survey report : final report
1997-06-01
The Suburban Mobility Authority for Regional Transportation (SMART) has installed an automatic scheduling and dispatch system (ASD) in Southeast Michigan in accordance with their plans to implement ITS as a site for an operational field test. The pur...
On Huygens' principle for Dirac operators associated to electromagnetic fields
Directory of Open Access Journals (Sweden)
CHALUB FABIO A.C.C.
2001-01-01
Full Text Available We study the behavior of massless Dirac particles, i.e., solutions of the Dirac equation with m = 0 in the presence of an electromagnetic field. Our main result (Theorem 1 is that for purely real or imaginary fields any Huygens type (in Hadamard's sense Dirac operators is equivalent to the free Dirac operator, equivalence given by changes of variables and multiplication (right and left by nonzero functions.
High field, low current operation of engineering test reactors
International Nuclear Information System (INIS)
Schwartz, J.; Cohn, D.R.; Bromberg, L.; Williams, J.E.C.
1987-06-01
Steady state engineering test reactors with high field, low current operation are investigated and compared to high current, lower field concepts. Illustrative high field ETR parameters are R = 3 m, α ∼ 0.5 m, B ∼ 10 T, β = 2.2% and I = 4 MA. For similar wall loading the fusion power of an illustrative high field, low current concept could be about 50% that of a lower field device like TIBER II. This reduction could lead to a 50% decrease in tritium consumption, resulting in a substantial decrease in operating cost. Furthermore, high field operation could lead to substantially reduced current drive requirements and cost. A reduction in current drive source power on the order of 40 to 50 MW may be attainable relative to a lower field, high current design like TIBER II implying a possible cost savings on the order of $200 M. If current drive is less efficient than assumed, the savings could be even greater. Through larger β/sub p/ and aspect ratio, greater prospects for bootstrap current operation also exist. Further savings would be obtained from the reduced size of the first wall/blanket/shield system. The effects of high fields on magnet costs are very dependent on technological assumptions. Further improvements in the future may lie with advances in superconducting and structural materials
Operator of Time and Generalized Schrödinger Equation
Directory of Open Access Journals (Sweden)
Slobodan Prvanović
2018-01-01
Full Text Available The equation describing the change of the state of the quantum system with respect to energy is introduced within the framework of the self-adjoint operator of time in nonrelativistic quantum mechanics. In this proposal, the operator of time appears to be the generator of the change of the energy, while the operator of energy that is conjugate to the operator of time generates the time evolution. Two examples, one with discrete time and the other with continuous one, are given and the generalization of Schrödinger equation is proposed.
On Some Analytic Operator Functions in the Theory of Hermitian Operators
Directory of Open Access Journals (Sweden)
Perch Melik-Adamyan
2014-01-01
Full Text Available A densely defined Hermitian operator $A_0$ with equal defect numbers is considered. Presentable by means of resolvents of a certain maximal dissipative or accumulative extensions of $A_0$, bounded linear operators acting from some defect subspace $\\mfn_\\gamma$ to arbitrary other $\\mfn_\\lambda$ are investigated. With their aid are discussed characteristic and Weyl functions. A family of Weyl functions is described, associated with a given self-adjoint extension of $A_0$. The specific property of Weyl function's factors enabled to obtain a modified formulas of von Neumann. In terms of characteristic and Weyl functions of suitably chosen extensions the resolvent of Weyl function is presented explicitly.
Assessment of field training for nuclear operations personnel
International Nuclear Information System (INIS)
White, M.
1995-08-01
Training of station personnel is an important component of the safe operation of the nuclear generating station. On-the-job training (OJT) is an important component of training. The AECB initiated this project to develop a process to assess the effectiveness of OJT for field operators, and perform an initial trial of the developed process. This report describes the recommended process to assess the effectiveness of OJT for field operators, as well as the results of the initial assessment at Pickering Nuclear Generating Station. The assessment's conclusions included: (1) Ontario Hydro policies and procedures are generally consistent with industry guidelines requiring a systematic approach to training; (2) Pickering NGS field operator performance is not always consistent with documented station requirements and standards, nor industry guidelines and practices; and (3) The Pickering NGS field operator on-the-job training is not consistent with a systematic approach to training, a requirement recognized in Ontario Hydro's Policy NGD 113, and does not contribute to a high level of performance in field operator tasks. Recommendations are made regarding the use of the developed process for future assessments of on-the-job training at nuclear power plants. (author). 36 refs., 4 tabs., 3 figs
Assessment of field training for nuclear operations personnel
Energy Technology Data Exchange (ETDEWEB)
White, M [Safety Management Services, Inc. (Canada)
1995-08-01
Training of station personnel is an important component of the safe operation of the nuclear generating station. On-the-job training (OJT) is an important component of training. The AECB initiated this project to develop a process to assess the effectiveness of OJT for field operators, and perform an initial trial of the developed process. This report describes the recommended process to assess the effectiveness of OJT for field operators, as well as the results of the initial assessment at Pickering Nuclear Generating Station. The assessment`s conclusions included: (1) Ontario Hydro policies and procedures are generally consistent with industry guidelines requiring a systematic approach to training; (2) Pickering NGS field operator performance is not always consistent with documented station requirements and standards, nor industry guidelines and practices; and (3) The Pickering NGS field operator on-the-job training is not consistent with a systematic approach to training, a requirement recognized in Ontario Hydro`s Policy NGD 113, and does not contribute to a high level of performance in field operator tasks. Recommendations are made regarding the use of the developed process for future assessments of on-the-job training at nuclear power plants. (author). 36 refs., 4 tabs., 3 figs.
International Nuclear Information System (INIS)
Frohlich, J.
1976-01-01
We prove that a Symanzik--Nelson positive quantum field theory, i.e., a quantum field theory derived from a Euclidean field theory, has a unique decomposition into pure phases which preserves Symanzik--Nelson positivity and Poincare covariance. We derive useful sufficient conditions for the breakdown of an internal symmetry of such a theory in its pure phases, for the self-adjointness and nontrivially (in the sense of Borchers classes) of its quantum fields, and the existence of time-ordered and retarded products. All these general results are then applied to the P (phi) 2 and the phi 3 4 quantum field models
The role of operator ordering in quantum field theory
International Nuclear Information System (INIS)
Suzuki, Tsuneo; Hirshfeld, A.C.; Leschke, H.
1980-01-01
We study the role of operator ordering in quantum field theory. Operator ordering techniques discussed in our previous papers in the quantum mechanical context are extended to field theory. In this case formally infinite terms appear which must be given a meaning in the framework of some definite regularization scheme. Different orderings for the non-commuting operators in the interaction Hamiltonian lead in general to different expressions for the Dyson-Wick expansion of the S-matrix, implying different Feynman rules. Different orderings correspond to different assignments for the initially undetermined values of the contractions occurring in closed-loop diagrams. Combining a special class of ordering schemes (u-ordering, a generalization of Weyl-ordering) with dimensional regularization leads to important simplifications, and in this case manipulations in which ordering complications are neglected may be justified. We use our methods to discuss gauge invariance in scalar electrodynamics, and the equivalent theorem for a reducible field theoretical model. (author)
Automated particulate sampler field test model operations guide
Energy Technology Data Exchange (ETDEWEB)
Bowyer, S.M.; Miley, H.S.
1996-10-01
The Automated Particulate Sampler Field Test Model Operations Guide is a collection of documents which provides a complete picture of the Automated Particulate Sampler (APS) and the Field Test in which it was evaluated. The Pacific Northwest National Laboratory (PNNL) Automated Particulate Sampler was developed for the purpose of radionuclide particulate monitoring for use under the Comprehensive Test Ban Treaty (CTBT). Its design was directed by anticipated requirements of small size, low power consumption, low noise level, fully automatic operation, and most predominantly the sensitivity requirements of the Conference on Disarmament Working Paper 224 (CDWP224). This guide is intended to serve as both a reference document for the APS and to provide detailed instructions on how to operate the sampler. This document provides a complete description of the APS Field Test Model and all the activity related to its evaluation and progression.
Safety and emergency preparedness considerations for geotechnical field operations
Energy Technology Data Exchange (ETDEWEB)
Wemple, R.P.
1989-04-01
The GEO Energy Technology Department at Sandia National Laboratories is involved in several remote-site drilling and/or experimental operations each year. In 1987, the Geothermal Research Division of the Department developed a general set of Safe Operating Procedures (SOPs) that could be applied to a variety of projects. This general set is supplemented by site-specific SOPs as needed. Effective field operations require: integration of safety and emergency preparedness planning with overall project planning, training of field personnel and inventorying of local emergency support resources, and, developing a clear line of responsibility and authority to enforce the safety requirements. Copies of SOPs used in recent operations are included as examples of working documents for the reader.
Polymer electrolyte fuel cells: flow field for efficient air operation
Energy Technology Data Exchange (ETDEWEB)
Buechi, F N; Tsukada, A; Haas, O; Scherer, G G [Paul Scherrer Inst. (PSI), Villigen (Switzerland)
1997-06-01
A new flow field was designed for a polymer electrolyte fuel cell stack with an active area of 200 cm{sup 2} for operation at low air stoichiometry and low air over pressure. Optimum of gas flow and channel dimensions were calculated based on the required pressure drop in the fluid. Single cells and a bi-cell stack with the new flow field show an improved current/voltage characteristic when operated at low air stoichiometries as compared to that of the previous non optimized design. (author) 4 figs., 3 refs.
Quantized fields and operators on a partial inner product space
International Nuclear Information System (INIS)
Shabani, J.
1985-11-01
We investigate the connection between the space OpV of all operators on a partial inner product space V and the weak sequential completion of the * algebra L + (Vsup(no.)) of all operators X such that Vsup(no.) is contained in D(X) intersection D(X*) and both X and its adjoint X* leave Vsup(no.) invariant. This connection gives a mathematical description of quantized fields in terms of elements of OpV. (author)
International Nuclear Information System (INIS)
Giri, Pulak Ranjan
2007-01-01
We perform a one-parameter family of self-adjoint extensions characterized by the parameter ω 0 . This allows us to get generic boundary conditions for the quantum oscillator on N-dimensional complex projective space (CP N ) and on its non-compact version, i.e., Lobachewski space (L N ) in the presence of a constant magnetic field. As a result, we get a family of energy spectra for the oscillator. In our formulation the already known result of this oscillator also belongs to the family. We have also obtained an energy spectrum which preserves all the symmetries (full-hidden symmetry and rotational symmetry) of the oscillator. The method of self-adjoint extensions has also been discussed for a conic oscillator in the presence of the constant magnetic field
Lectures on algebraic quantum field theory and operator algebras
International Nuclear Information System (INIS)
Schroer, Bert
2001-04-01
In this series of lectures directed towards a mainly mathematically oriented audience I try to motivate the use of operator algebra methods in quantum field theory. Therefore a title as why mathematicians are/should be interested in algebraic quantum field theory would be equally fitting. besides a presentation of the framework and the main results of local quantum physics these notes may serve as a guide to frontier research problems in mathematical. (author)
Elements of Hilbert spaces and operator theory
Vasudeva, Harkrishan Lal
2017-01-01
The book presents an introduction to the geometry of Hilbert spaces and operator theory, targeting graduate and senior undergraduate students of mathematics. Major topics discussed in the book are inner product spaces, linear operators, spectral theory and special classes of operators, and Banach spaces. On vector spaces, the structure of inner product is imposed. After discussing geometry of Hilbert spaces, its applications to diverse branches of mathematics have been studied. Along the way are introduced orthogonal polynomials and their use in Fourier series and approximations. Spectrum of an operator is the key to the understanding of the operator. Properties of the spectrum of different classes of operators, such as normal operators, self-adjoint operators, unitaries, isometries and compact operators have been discussed. A large number of examples of operators, along with their spectrum and its splitting into point spectrum, continuous spectrum, residual spectrum, approximate point spectrum and compressio...
Vertex operator construction of superconformal ghosts and string field theory
International Nuclear Information System (INIS)
Ezawa, Z.F.; Nakamura, S.; Tezuka, A.
1987-01-01
Superconformal ghosts in string theories are characterized by the SU(1,1) Kac-Moody algebra with central charge -1/2. These ghost fields are constructed as the vertex operators realizing spinor representations of the Kac-Moody algebra. Representations of the canonical commutation relations of the superconformal ghosts are analyzed extensively. All irreducible representations are found to possess only the trivial inner product but for one exceptional case. Consequently, in superstring field theory it is necessary to consider reducible representations in general. Hilbert spaces with a non-trivial inner product are explicitly obtained upon which second quantization of superstring may be carried out. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Smirnov, A. G., E-mail: smirnov@lpi.ru [I. E. Tamm Theory Department, P. N. Lebedev Physical Institute, Leninsky Prospect 53, Moscow 119991 (Russian Federation)
2015-12-15
We develop a general technique for finding self-adjoint extensions of a symmetric operator that respects a given set of its symmetries. Problems of this type naturally arise when considering two- and three-dimensional Schrödinger operators with singular potentials. The approach is based on constructing a unitary transformation diagonalizing the symmetries and reducing the initial operator to the direct integral of a suitable family of partial operators. We prove that symmetry preserving self-adjoint extensions of the initial operator are in a one-to-one correspondence with measurable families of self-adjoint extensions of partial operators obtained by reduction. The general scheme is applied to the three-dimensional Aharonov-Bohm Hamiltonian describing the electron in the magnetic field of an infinitely thin solenoid. We construct all self-adjoint extensions of this Hamiltonian, invariant under translations along the solenoid and rotations around it, and explicitly find their eigenfunction expansions.
Operation of cold-cathode gauges in high magnetic fields
International Nuclear Information System (INIS)
Thomas, S.R. Jr.; Goerz, D.A.; Pickles, W.L.
1985-01-01
The Mirror Fusion Test Facility (MFTF-B), under construction at LLNL, requires measurement of the neutral gas density in high magnetic fields near the plasma at several axial regions. This Background Gas Pressure (BGP) diagnostic will help us understand the role of background neutrals in particle and power balance, particularly in the maintenance of the cold halo plasma that shields the hot core plasma from the returning neutrals. It consists of several cold-cathode, magnetron-type gauges stripped of their permanent magnets, and utilizes the MFTF-B ambient B-field in strengths of 5 to 25 kG. Similar gauges have operated in TMX-U in B-fields up to 3 kG. To determine how well the gauges will perform, we assembled a test stand which operated magnetron gauges in an external, uniform magnetic field of up to 30 kG, over a pressure range of 1E-8 T to 1E-5 T, at several cathode voltages. This paper describes the test stand and presents the results of the tests
Extension of TFTR operations to higher toroidal field levels
International Nuclear Information System (INIS)
Woolley, R.D.
1995-01-01
For the past year, TFTR has sometimes operated at extended toroidal field (TF) levels. The extension to 5.6 Tesla (79 kA) was crucial for TFTR's November 1994 10.7 MW DT fusion power record. The extension to 6.0 Tesla (85 kA) was commissioned on 9 September 1995. There are several reasons that one could expect the TF coils to survive the higher stresses that develop at higher fields. They were designed to operate at 5.2 Tesla with a vertical field of 0.5 Tesla, whereas the actual vertical field needed for the plasma does not exceed 0.35 Tesla. Their design specification explicitly required they survive some pulses at 6.0 Tesla. TF coil mechanical analysis computer models available during coil design were crude, leading to conservative design. And design analyses also had to consider worst-case misoperations that TFTR's real time Coil Protection Calculators (CPCs) now positively prevent from occurring
Yanqing solar field: Dynamic optical model and operational safety analysis
International Nuclear Information System (INIS)
Zhao, Dongming; Wang, Zhifeng; Xu, Ershu; Zhu, Lingzhi; Lei, Dongqiang; Xu, Li; Yuan, Guofeng
2017-01-01
Highlights: • A dynamic optical model of the Yanqing solar field was built. • Tracking angle characteristics were studied with different SCA layouts and time. • The average energy flux was simulated across four clear days. • Influences of defocus angles for energy flux were analyzed. - Abstract: A dynamic optical model was established for the Yanqing solar field at the parabolic trough solar thermal power plant and a simulation was conducted on four separate days of clear weather (March 3rd, June 2nd, September 25th, December 17th). The solar collector assembly (SCA) was comprised of a North-South and East-West layout. The model consisted of the following modules: DNI, SCA operational, and SCA optical. The tracking angle characteristics were analyzed and the results showed that the East-West layout of the tracking system was the most viable. The average energy flux was simulated for a given time period and different SCA layouts, yielding an average flux of 6 kW/m 2 , which was then used as the design and operational standards of the Yanqing parabolic trough plant. The mass flow of North-South layout was relatively stable. The influences of the defocus angles on both the average energy flux and the circumferential flux distribution were also studied. The results provided a theoretical basis for the following components: solar field design, mass flow control of the heat transfer fluid, design and operation of the tracking system, operational safety of SCAs, and power production prediction in the Yanqing 1 MW parabolic trough plant.
Renormalizing the kinetic energy operator in elementary quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Coutinho, F A B [Faculdade de Medicina, Universidade de Sao Paulo e LIM 01-HCFMUSP, 05405-000 Sao Paulo (Brazil); Amaku, M [Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, 05508-970 Sao Paulo (Brazil)], E-mail: coutinho@dim.fm.usp.br
2009-09-15
In this paper, we consider solutions to the three-dimensional Schroedinger equation of the form {psi}(r) = u(r)/r, where u(0) {ne} 0. The expectation value of the kinetic energy operator for such wavefunctions diverges. We show that it is possible to introduce a potential energy with an expectation value that also diverges, exactly cancelling the kinetic energy divergence. This renormalization procedure produces a self-adjoint Hamiltonian. We solve some problems with this new Hamiltonian to illustrate its usefulness.
Renormalizing the kinetic energy operator in elementary quantum mechanics
International Nuclear Information System (INIS)
Coutinho, F A B; Amaku, M
2009-01-01
In this paper, we consider solutions to the three-dimensional Schroedinger equation of the form ψ(r) = u(r)/r, where u(0) ≠ 0. The expectation value of the kinetic energy operator for such wavefunctions diverges. We show that it is possible to introduce a potential energy with an expectation value that also diverges, exactly cancelling the kinetic energy divergence. This renormalization procedure produces a self-adjoint Hamiltonian. We solve some problems with this new Hamiltonian to illustrate its usefulness.
On the uncertainty relations for vector-valued operators
International Nuclear Information System (INIS)
Chistyakov, A.L.
1976-01-01
In analogy with the expression for the Heisenberg incertainty principle in terms of dispersions by means of the Weyl inequality, in the case of one-dimensional quantum mechanical quantities, the principle for many-dimensional quantities can be expressed in terms of generalized dispersions and covariance matrices by means of inequalities similar to the Weyl unequality. The proofs of these inequalities are given in an abstract form, not only for the physical vector quantities, but also for arbitrary vector-valued operators with commuting self-adjoint components
Field Operations Program Neighborhood Electric Vehicles - Fleet Survey
Energy Technology Data Exchange (ETDEWEB)
Francfort, James Edward; Carroll, M.
2001-07-01
This report summarizes a study of 15 automotive fleets that operate neighborhood electric vehicles(NEVs) in the United States. The information was obtained to help Field Operations Program personnel understand how NEVs are being used, how many miles they are being driven, and if they are being used to replace other types of fleet vehicles or as additions to fleets. (The Field Operations Program is a U.S. Department of Energy Program within the DOE Office of Energy Efficiency and Renewable Energy, Transportation Technologies). The NEVs contribution to petroleum avoidance and cleaner air can be estimated based on the miles driven and by assuming gasoline use and air emissions values for the vehicles being replaced. Gasoline and emissions data for a Honda Civic are used as the Civic has the best fuel use for a gasoline-powered vehicle and very clean emissions. Based on these conservation assumptions, the 348 NEVs are being driven a total of about 1.2 million miles per year. This equates to an average of 3,409 miles per NEV annually or 9 miles per day. It is estimated that 29,195 gallons of petroleum use is avoided annually by the 348 NEVs. This equates to 87 gallons of petroleum use avoided per NEV, per year. Using the 348 NEVs avoids the generation of at least 775 pounds of smog- forming emissions annually.
Field Operations Program - Neighborhood Electric Vehicle Fleet Use
Energy Technology Data Exchange (ETDEWEB)
Francfort, J. E.; Carroll, M. R.
2001-07-02
This report summarizes a study of 15 automotive fleets that operate neighborhood electric vehicles (NEVs) in the United States. The information was obtained to help Field Operations Program personnel understand how NEVs are being used, how many miles they are being driven, and if they are being used to replace other types of fleet vehicles or as additions to fleets. (The Field Operations Program is a U.S. Department of Energy Program within the DOE Office of Energy Efficiency and Renewable Energy, Transportation Technologies). The NEVs contribution to petroleum avoidance and cleaner air can be estimated based on the miles driven and by assuming gasoline use and air emissions values for the vehicles being replaced. Gasoline and emissions data for a Honda Civic are used as the Civic has the best fuel use for a gasoline-powered vehicle and very clean emissions. Based on these conservation assumptions, the 348 NEVs are being driven a total of about 1.2 million miles per year. This equates to an average of 3,409 miles per NEV annually or 9 miles per day. It is estimated that 29,195 gallons of petroleum use is avoided annually by the 348 NEVs. This equates to 87 gallons of petroleum use avoided per NEV, per year. Using the 348 NEVs avoids the generation of at least 775 pounds of smog-forming emissions annually.
OSE inspection of protection program operations field perspective of inspections
International Nuclear Information System (INIS)
Brown, R.W.; Martin, H.R.
1987-01-01
Protection Program Operations includes three functional areas: Physical Protection Systems, Protective Forces, and System Performance Testing. The Office of Security Evaluations (OSE) inspects field offices in these areas by evaluating programs relative to Standards and Criteria and by performing a variety of exercises and other types of tests to assure protective systems are effective and maintained at a proper level to meet the defined threat. Their perception of the OSE inspections has been positive. The approach taken by ID, with key areas/activities emphasized, during each phase of the field inspection process is described in this report. The most important areas for field offices to concentrate are: inspection preparations through self-evaluation, improving communications, assigning knowledgeable trusted agents, increasing awareness of facility procedures and operations, and assuring daily validations of inspected areas. Emphasis is placed on striving for a balance in reporting both positive and negative findings, and for consistency between ratings and the importance of report findings. OSE efforts to develop improved rating methodologies are encouraged
Quadratic Plus Linear Operators which Preserve Pure States of Quantum Systems: Small Dimensions
International Nuclear Information System (INIS)
Saburov, Mansoor
2014-01-01
A mathematical formalism of quantum mechanics says that a pure state of a quantum system corresponds to a vector of norm 1 and an observable is a self-adjoint operator on the space of states. It is of interest to describe all linear or nonlinear operators which preserve the pure states of the system. In the linear case, it is nothing more than isometries of Hilbert spaces. In the nonlinear case, this problem was open. In this paper, in the small dimensional spaces, we shall describe all quadratic plus linear operators which preserve pure states of the quantum system
Dirac operators and spectral triples for some fractal sets built on curves
DEFF Research Database (Denmark)
Christensen, Erik; Ivan, Cristina; Lapidus, Michel L.
2008-01-01
A spectral triple is an object which is described using an algebra of operators on a Hilbert space and an unbounded self-adjoint operator, called a Dirac operator. This model may be applied to the study of classical geometrical objects .The article contains a construction of a spectral triple ass...... associated to some classical fractal subsets of the plane, and it is demonstrated that you can read of many classical geometrical structures, such as distance, measure and Hausdorff dimension from the spectral triple....
A Compact RFID Reader Antenna for UHF Near-Field and Far-Field Operations
Directory of Open Access Journals (Sweden)
Lai Xiao zheng
2013-01-01
Full Text Available A compact loop antenna is presented for mobile ultrahigh frequency (UHF radio frequency identification (RFID application. This antenna, printed on a 0.8 mm thick FR4 substrate with a small size of 31 mm × 31 mm, achieves good impedance bandwidth from 897 to 928 MHz, which covers USA RFID Band (902–928 MHz. The proposed loop configuration, with a split-ring resonator (SRR coupled inside it, demonstrates strong and uniform magnetic field distribution in the near-field antenna region. Its linearly polarized radiation pattern provides available far-field gain. Finally, the reading capabilities of antenna are up to 56 mm for near-field and 1.05 m for far-field UHF RFID operations, respectively.
QED fermi fields as operator-valued distributions and anomalies
International Nuclear Information System (INIS)
Grange, P.; Werner, E.
2005-01-01
The treatment of fields as operator-valued distributions (OPVD) is recalled with the emphasis on the importance of causality following the work of Epstein and Glaser. Gauge-invariant theories demand the extension of the usual translation operation on OPVD, thereby leading to a generalized QED formulation. At D = 2 the solvability of the Schwinger model is totally preserved. At D = 4 the paracompactness property of the Euclidean manifold permits the use of test functions which are a decomposition of unity and thereby provides a natural justification and extension of the non-perturbative heat kernel method (Fujikawa) for Abelian anomalies. On the Minkowski manifold the specific role of causality in the restauration of gauge invariance (and mass generation for QED 2 is exemplified in a simple way. (author)
Total connectivity speeds research and support of field operations
International Nuclear Information System (INIS)
Himes, R.E.; Frost, K.I.; Henry, S.R.; Funkhouser, J.D.
1992-01-01
This paper reports that research and field support roles in the oilfield service industry have become increasingly complex in the last 15 years. Experimental apparatus are more dependent on the data-acquisition and processing capabilities of computers as the amount of data generated increases. Therefore, the need to network these computers for data transport has significantly increased. The type of network system selected depends on the goals to be achieved. Incorporation of existing equipment, communication between systems of different architectures, and future expandability are only a few of the necessary attributes. With these in mind, a computer network system was designed and is being implemented. The system combines local- and wide-area networks (LAN's or WAN's) of different protocols to acquire, process, and transport information worldwide. The result is faster development of new products and quicker response in support of field operations
The continuous spectrum and the effect of parametric resonance. The case of bounded operators
International Nuclear Information System (INIS)
Skazka, V V
2014-01-01
The paper is concerned with the Mathieu-type differential equation u ″ =−A 2 u+εB(t)u in a Hilbert space H. It is assumed that A is a bounded self-adjoint operator which only has an absolutely continuous spectrum and B(t) is almost periodic operator-valued function. Sufficient conditions are obtained under which the Cauchy problem for this equation is stable for small ε and hence free of parametric resonance. Bibliography: 10 titles
Basic properties of the current-current correlation measure for random Schroedinger operators
International Nuclear Information System (INIS)
Hislop, Peter D.; Lenoble, Olivier
2006-01-01
The current-current correlation measure plays a crucial role in the theory of conductivity for disordered systems. We prove a Pastur-Shubin-type formula for the current-current correlation measure expressing it as a thermodynamic limit for random Schroedinger operators on the lattice and the continuum. We prove that the limit is independent of the self-adjoint boundary conditions and independent of a large family of expanding regions. We relate this finite-volume definition to the definition obtained by using the infinite-volume operators and the trace-per-unit volume
International Nuclear Information System (INIS)
Chauvin, S.; Gibergues, M. L.; Wuethrich, G.; Picard, D.; Desreumaux, J. P.; Bouillet, J. C.
2009-01-01
In order to investigate the exposure of operational personnel to radiofrequency electromagnetic fields when working for a mobile telephone operator, exposimeters were used to make individual records on 23 Technical Operations personnel (mobile telephone maintenance staff) and also on 22 Other Workers. The exposure densities, to which each of the 45 subjects was subjected, were quantified using 229 exposure indicators. Cluster analysis techniques were applied to the data, in an attempt to show that they would re-emerge as belonging to one of the two groups, i.e. the Technical Operational Personnel group or the Other Workers group. This exploratory investigation has shown that the cluster analysis does not reveal a sufficiently reliable emergence of the two groups, even though certain exposure indicators were significantly different for the two groups. In addition, the use of a Learning Group method does not lead to the discovery of a predictive law that could identify the Technical Operational Personnel as a sub-group within the overall group. (authors)
The imitator of nuclear explosion signals for field operations
International Nuclear Information System (INIS)
Wang Lusong; Xie Yujun; Tan Youjin; Wang Liping
1999-01-01
According to the present system of the nuclear explosion monitoring equipment (NEME), the imitator of nuclear explosion signals for field operation is urgently needed by NEME, which has been fitted out to the army and some new types that will be finalized soon. The authors have made the imitator for the equipment, and as the cause of this research, it can be used not only in training and maintenance for army but also in research and production for scientific research institutions and industrial enterprise. Function of this imitator is to imitate the NEMP, the light and shock wave signals of nuclear explosion in proper order. The time difference of the process accords with the true location of nuclear explosion. This research is of great military importance
Hysteresis phenomenon during operation of gas condensate fields
Energy Technology Data Exchange (ETDEWEB)
Sadykh-Zade, E S; Karakashev, V K; Ismailov, D Kh
1966-01-01
Hysteresis behavior of gas-condensate mixtures was studied with a PVT apparatus. The study was conducted at 26 and 80/sup 0/C, with recombined samples having gas factors of 3,000, 6,500, and 10,000 cu meters per ton. Pressure on samples was decreased or increased at rates of 0.2; 0.1; 0.05; and 0.025 atm per sec. Composition of gas- condensate is given. It is reported that different amounts of liquid were produced by condensation and evaporation processes, i.e., results depended on whether pressure was being increased or decreased. It is suggested that the effect of hysteresis should be considered in operation of gas-condensate fields.
What SCADA systems can offer to optimize field operations
International Nuclear Information System (INIS)
McLean, D.J.
1997-01-01
A new technology developed by Kenomic Controls Ltd. of Calgary was designed to solve some of the problems associated with producing gas wells with high gas to liquids ratios. The rationale and the system architecture of the SCADA (Supervisory Control and Data Acquisition) system were described. The most common application of SCADA is the Electronic Flow Measurement (EFM) installation using a solar or thermo-electric generator as a power source for the local electronics. Benefits that the SCADA system can provide to producing fields such as increased revenue, decreased operating costs, decreased fixed capital and working capital requirements, the planning and implementation strategies for SCADA were outlined. A case history of a gas well production optimization system in the Pierceland area of northwest Saskatchewan was provided as an illustrative example. 9 figs
Integration of field data into operational snowmelt-runoff models
International Nuclear Information System (INIS)
Brandt, M.; Bergström, S.
1994-01-01
Conceptual runoff models have become standard tools for operational hydrological forecasting in Scandinavia. These models are normally based on observations from the national climatological networks, but in mountainous areas the stations are few and sometimes not representative. Due to the great economic importance of good hydrological forecasts for the hydro-power industry attempts have been made to improve the model simulations by support from field observations of the snowpack. The snowpack has been mapped by several methods; airborne gamma-spectrometry, airborne georadars, satellites and by conventional snow courses. The studies cover more than ten years of work in Sweden. The conclusion is that field observations of the snow cover have a potential for improvement of the forecasts of inflow to the reservoirs in the mountainous part of the country, where the climatological data coverages is poor. This is pronounced during years with unusual snow distribution. The potential for model improvement is smaller in the climatologically more homogeneous forested lowlands, where the climatological network is denser. The costs of introduction of airborne observations into the modelling procedure are high and can only be justified in areas of great hydropower potential. (author)
Energy Technology Data Exchange (ETDEWEB)
Vaganova, N. A., E-mail: vna@imm.uran.ru [Institute of Mathematics and Mechanics of Ural Branch of Russian Academy of Sciences, Ekaterinburg (Russian Federation); Filimonov, M. Yu., E-mail: fmy@imm.uran.ru [Ural Federal University, Ekaterinburg, Russia and Institute of Mathematics and Mechanics of Ural Branch of Russian Academy of Sciences, Ekaterinburg (Russian Federation)
2015-11-30
A mathematical model, numerical algorithm and program code for simulation and long-term forecasting of changes in permafrost as a result of operation of a multiple well pad of northern oil and gas field are presented. In the model the most significant climatic and physical factors are taken into account such as solar radiation, determined by specific geographical location, heterogeneous structure of frozen soil, thermal stabilization of soil, possible insulation of the objects, seasonal fluctuations in air temperature, and freezing and thawing of the upper soil layer. Results of computing are presented.
South Fence Road -- Phase 1 field operations summary
Energy Technology Data Exchange (ETDEWEB)
McCord, J.P. [INTERA, Inc., Albuquerque, NM (United States); Neel, D. [GRAM, Inc., Albuquerque, NM (United States)
1996-03-01
The South Fence Road (SFR) project is part of the Sandia National Laboratories, New Mexico (SNL/NM) Site-Wide Hydrogeologic Characterization (SWHC) task. The SWHC task has as its objective the reduction of uncertainty about the rate and direction of groundwater flow in the SNL/NM/Kirtland Air Force Base (KAFB) area. The SFR project area is located along the southern boundary of SNL/KAFB. This project area was selected to provide site-specific information related to geology and groundwater hydrology within the Hubbell Spring/Tijeras/Sandia fault complex. Specific objectives included determining the depth to the Santa Fe Group/bedrock contact, the depth to the water table, and the hydrogeologic complexities related to faulting. This report is a basic data report from the first phase of field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-1D and SFR-1S, SFR-2, SFR-3D and SFR-3S, and SFR-4. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.
South Fence Road -- Phase 1 field operations summary
International Nuclear Information System (INIS)
McCord, J.P.; Neel, D.
1996-03-01
The South Fence Road (SFR) project is part of the Sandia National Laboratories, New Mexico (SNL/NM) Site-Wide Hydrogeologic Characterization (SWHC) task. The SWHC task has as its objective the reduction of uncertainty about the rate and direction of groundwater flow in the SNL/NM/Kirtland Air Force Base (KAFB) area. The SFR project area is located along the southern boundary of SNL/KAFB. This project area was selected to provide site-specific information related to geology and groundwater hydrology within the Hubbell Spring/Tijeras/Sandia fault complex. Specific objectives included determining the depth to the Santa Fe Group/bedrock contact, the depth to the water table, and the hydrogeologic complexities related to faulting. This report is a basic data report from the first phase of field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-1D and SFR-1S, SFR-2, SFR-3D and SFR-3S, and SFR-4. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project
International Nuclear Information System (INIS)
Piguet, M.; Favennec, J.M.
1997-01-01
The paper presents a field trial held in EDF's R and D laboratories concerning smart field instruments (sensors, I/O modules, transmitters) operating on the WorldFIP field-bus. The trial put into operation a supervisory control and data acquisition (SCADA) system on the field-bus with available industrial field devices and software tools. The field trial enables EDF's teams to address the inter-operability issue regarding smart field devices and to prepare the forthcoming step from analog to fully digital measurement technology by evaluating new services and higher performances provided. Possible architectures for process control and on-site testing purposes have been identified. A first application for a flow-measuring rig is under way. It implements a WorldFIP field-bus based DCS with FIP/HART multiplexers, FIP and HART smart devices (sensors and actuators) and a field management system. (authors)
On weakly D-differentiable operators
DEFF Research Database (Denmark)
Christensen, Erik
2016-01-01
Let DD be a self-adjoint operator on a Hilbert space HH and aa a bounded operator on HH. We say that aa is weakly DD-differentiable, if for any pair of vectors ξ,ηξ,η from HH the function 〈eitDae−itDξ,η〉〈eitDae−itDξ,η〉 is differentiable. We give an elementary example of a bounded operator aa......, such that aa is weakly DD-differentiable, but the function eitDae−itDeitDae−itD is not uniformly differentiable. We show that weak DD-differentiability may be characterized by several other properties, some of which are related to the commutator (Da−aD)...
Smart Infrared Inspection System Field Operational Test Final Report
Energy Technology Data Exchange (ETDEWEB)
Siekmann, Adam [ORNL; Capps, Gary J [ORNL; Franzese, Oscar [ORNL; Lascurain, Mary Beth [ORNL
2011-06-01
The Smart InfraRed Inspection System (SIRIS) is a tool designed to assist inspectors in determining which vehicles passing through the SIRIS system are in need of further inspection by measuring the thermal data from the wheel components. As a vehicle enters the system, infrared cameras on the road measure temperatures of the brakes, tires, and wheel bearings on both wheel ends of commercial motor vehicles (CMVs) in motion. This thermal data is then presented to enforcement personal inside of the inspection station on a user friendly interface. Vehicles that are suspected to have a violation are automatically alerted to the enforcement staff. The main goal of the SIRIS field operational test (FOT) was to collect data to evaluate the performance of the prototype system and determine the viability of such a system being used for commercial motor vehicle enforcement. From March 2010 to September 2010, ORNL facilitated the SIRIS FOT at the Greene County Inspection Station (IS) in Greeneville, Tennessee. During the course of the FOT, 413 CMVs were given a North American Standard (NAS) Level-1 inspection. Of those 413 CMVs, 384 were subjected to a SIRIS screening. A total of 36 (9.38%) of the vehicles were flagged by SIRIS as having one or more thermal issues; with brakes issues making up 33 (91.67%) of those. Of the 36 vehicles flagged as having thermal issues, 31 (86.11%) were found to have a violation and 30 (83.33%) of those vehicles were placed out-of-service (OOS). Overall the enforcement personnel who have used SIRIS for screening purposes have had positive feedback on the potential of SIRIS. With improvements in detection algorithms and stability, the system will be beneficial to the CMV enforcement community and increase overall trooper productivity by accurately identifying a higher percentage of CMVs to be placed OOS with minimal error. No future evaluation of SIRIS has been deemed necessary and specifications for a production system will soon be drafted.
Wireless networks of opportunity in support of secure field operations
Stehle, Roy H.; Lewis, Mark
1997-02-01
Under funding from the Defense Advanced Research Projects Agency (DARPA) for joint military and law enforcement technologies, demonstrations of secure information transfer in support of law enforcement and military operations other than war, using wireless and wired technology, were held in September 1996 at several locations in the United States. In this paper, the network architecture, protocols, and equipment supporting the demonstration's scenarios are presented, together with initial results, including lessons learned and desired system enhancements. Wireless networks of opportunity encompassed in-building (wireless-LAN), campus-wide (Metricom Inc.), metropolitan (AMPS cellular, CDPD), and national (one- and two-way satellite) systems. Evolving DARPA-sponsored packet radio technology was incorporated. All data was encrypted, using multilevel information system security initiative (MISSI)FORTEZZA technology, for carriage over unsecured and unclassified commercial networks. The identification and authentication process inherent in the security system permitted logging for database accesses and provided an audit trail useful in evidence gathering. Wireless and wireline communications support, to and between modeled crisis management centers, was demonstrated. Mechanisms for the guarded transport of data through the secret-high military tactical Internet were included, to support joint law enforcement and crisis management missions. A secure World Wide Web (WWW) browser forms the primary, user-friendly interface for information retrieval and submission. The WWW pages were structured to be sensitive to the bandwidth, error rate, and cost of the communications medium in use (e.g., the use of and resolution for graphical data). Both still and motion compressed video were demonstrated, along with secure voice transmission from laptop computers in the field. Issues of network bandwidth, airtime costs, and deployment status are discussed.
Duality property for a hermitian scalar field
International Nuclear Information System (INIS)
Bisognano, J.J.
1975-01-01
A general hermitian scalar Wightman field is considered. On the Hilbert space of physical states ''natural'' domains for certain complex Lorentz transformations are constructed, and a theorem relating these transformations to the TCP symmetry is stated and proved. Under the additional assumption that the field is ''locally'' essentially self-adjoint, duality is considered for the algebras generated by spectral projections of smeared fields. For a class of unbounded regions duality is proved, and for certain bounded regions ''local'' extensions of the algebras are constructed which satisfy duality. The relationship of the arguments presented to the Tomita--Takesaki theory of modular Hilbert algebras is discussed. A separate analysis for the free field is also given. (auth)
Gohberg, Israel
2001-01-01
rii application of linear operators on a Hilbert space. We begin with a chapter on the geometry of Hilbert space and then proceed to the spectral theory of compact self adjoint operators; operational calculus is next presented as a nat ural outgrowth of the spectral theory. The second part of the text concentrates on Banach spaces and linear operators acting on these spaces. It includes, for example, the three 'basic principles of linear analysis and the Riesz Fredholm theory of compact operators. Both parts contain plenty of applications. All chapters deal exclusively with linear problems, except for the last chapter which is an introduction to the theory of nonlinear operators. In addition to the standard topics in functional anal ysis, we have presented relatively recent results which appear, for example, in Chapter VII. In general, in writ ing this book, the authors were strongly influenced by re cent developments in operator theory which affected the choice of topics, proofs and exercises. One ...
Neutron field control cybernetics model of RBMK reactor operator
International Nuclear Information System (INIS)
Polyakov, V.V.; Postnikov, V.V.; Sviridenkov, A.N.
1992-01-01
Results on parameter optimization for cybernetics model of RBMK reactor operator by power release control function are presented. Convolutions of various criteria applied previously in algorithms of the program 'Adviser to reactor operator' formed the basis of the model. 7 refs.; 4 figs
Using virtual reality technology to include field operators in simulation and training
International Nuclear Information System (INIS)
Nystad, E.; Strand, S.
2006-01-01
By using virtual reality technology, field operators can be included in simulator training. A study has been performed where field operators could perform their activities in a virtual plant and communicate with a control room operator who was placed in a physical control room simulator. This paper describes the use of VR technology in the study and how the operators experienced interacting with the virtual plant. (author)
The foliation operator in history quantum field theory
International Nuclear Information System (INIS)
Isham, C.J.; Savvidou, K.
2002-01-01
As a preliminary to discussing the quantization of the foliation in a history form of general relativity, we show how the discussion in an earlier work [J. Math. Phys. 43, 3053 (2002)] of a history version of free, scalar quantum field theory can be augmented in such a way as to include the quantization of the unit-length, timelike vector that determines a Lorentzian foliation of Minkowski space-time. We employ a Hilbert bundle construction that is motivated by (i) discussing the role of the external Lorentz group in the existing history quantum field theory [J. Math. Phys. 43, 3053 (2002)] and (ii) considering a specific representation of the extended history algebra obtained from the multi-symplectic representation of scalar field theory
Exposure levels to electromagnetic fields in usual operative situations
International Nuclear Information System (INIS)
Bemardi, C; Bemardi, T.; Testoni, G.; Zannoli, R.; Tubertini, O
1997-01-01
In the last few years, the whole population have been repeatedly solicited from media about the possible negative effects of E.M. Fields involved in all the social activities. This determinate the need of evaluations of the risks in different conditions, supported by accurate measurement protocols. This paper describes the procedures and the results of measurements in four different conditions, which involve the whole population and/or workers of a specific field. Results have been used both to increase the knowledge of the E.M. exposure levels and to evaluate the risks, with respect to the National Rules and Guidelines. (authors)
Analytic operator approach to fermionic lattice field theories
International Nuclear Information System (INIS)
Duncan, A.
1985-01-01
An analytic Lanczos algorithm previously used to extract the spectrum of bosonic lattice field theories in the continuum region is extended to theories with fermions. The method is illustrated in detail for the (1+1)-dimensional Gross-Neveu model. All parameters in the model (coupling, lattice size N, number of fermion flavors Nsub(F), etc.) appear explicitly in analytic formulas for matrix elements of the hamiltonian. The method is applied to the calculation of the collective field vacuum expectation value and the mass gap, and excellent agreement obtained with explicit results available from the large Nsub(F) solution of the model. (orig.)
Global operator expansions in conformally invariant relativistic quantum field theory
International Nuclear Information System (INIS)
Schoer, B.; Swieca, J.A.; Voelkel, A.H.
1974-01-01
A global conformal operator expansions in the Minkowski region in several models and their formulation in the general theory is presented. Whereas the vacuum expansions are termwise manisfestly conformal invariant, the expansions away from the vacuum do not share this property
Force Structure Matters: The US Field Artillery in Operational Art
2015-05-23
2003 (Fort Sill, OK: US Army Field Artillery Center, 2004), 62-63. 3 Sean Bateman and Steven Hady, “King of Battle Once Again: An Organizational...To What Ends Military Power?” International Security 4, no. 4 (Spring 1980): 3- 35. Bateman , Sean and Steven Hady. “King of Battle Once Again: An
The spectral theorem for quaternionic unbounded normal operators based on the S-spectrum
Energy Technology Data Exchange (ETDEWEB)
Alpay, Daniel, E-mail: dany@math.bgu.ac.il; Kimsey, David P., E-mail: dpkimsey@gmail.com [Department of Mathematics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Colombo, Fabrizio, E-mail: fabrizio.colombo@polimi.it [Politecnico di Milano, Dipartimento di Matematica, Via E. Bonardi, 9, 20133 Milano (Italy)
2016-02-15
In this paper we prove the spectral theorem for quaternionic unbounded normal operators using the notion of S-spectrum. The proof technique consists of first establishing a spectral theorem for quaternionic bounded normal operators and then using a transformation which maps a quaternionic unbounded normal operator to a quaternionic bounded normal operator. With this paper we complete the foundation of spectral analysis of quaternionic operators. The S-spectrum has been introduced to define the quaternionic functional calculus but it turns out to be the correct object also for the spectral theorem for quaternionic normal operators. The lack of a suitable notion of spectrum was a major obstruction to fully understand the spectral theorem for quaternionic normal operators. A prime motivation for studying the spectral theorem for quaternionic unbounded normal operators is given by the subclass of unbounded anti-self adjoint quaternionic operators which play a crucial role in the quaternionic quantum mechanics.
Multi-Center Traffic Management Advisor Operational Field Test Results
Farley, Todd; Landry, Steven J.; Hoang, Ty; Nickelson, Monicarol; Levin, Kerry M.; Rowe, Dennis W.
2005-01-01
The Multi-Center Traffic Management Advisor (McTMA) is a research prototype system which seeks to bring time-based metering into the mainstream of air traffic control (ATC) operations. Time-based metering is an efficient alternative to traditional air traffic management techniques such as distance-based spacing (miles-in-trail spacing) and managed arrival reservoirs (airborne holding). While time-based metering has demonstrated significant benefit in terms of arrival throughput and arrival delay, its use to date has been limited to arrival operations at just nine airports nationally. Wide-scale adoption of time-based metering has been hampered, in part, by the limited scalability of metering automation. In order to realize the full spectrum of efficiency benefits possible with time-based metering, a much more modular, scalable time-based metering capability is required. With its distributed metering architecture, multi-center TMA offers such a capability.
International co-operation in the field of wind energy
Energy Technology Data Exchange (ETDEWEB)
Wolff, J. [VTT Energy, Espoo (Finland)
1998-10-01
The use of wind energy is expanding rapidly worldwide. At the end of 1996 over 6000 MW was installed and the annual increase has during the last years exceeded 1000 MW. The development is also reaching more and more countries. In order to maintain technical and commercial development international co-operation is needed to secure cost-effectiveness, reliability and safety of the technology. International recommendations, harmonisation and standardisation is promoted by several international organizations like IEA, IEC and the classification organisations
On the connection between quantum fields and von Neumann algebras of local operators
International Nuclear Information System (INIS)
Driessler, W.; Summers, S.J.; Wichmann, E.H.
1986-01-01
The relationship between a standard local quantum field and a net of local von Neumann algebras is discussed. Two natural possibilities for such an association are identified, and conditions for these to obtain are found. It is shown that the local net can naturally be so chosen that it satisfies the Special Condition of Duality. The notion of an intrinsically local field operator is introduced, and it is shown that such an operator defines a local net with which the field is locally associated. A regularity condition on the field is formulated, and it is shown that if this condition holds, then there exists a unique local net with which the field is locally associated if and only if the field algebra contains at least one intrinsically local operator. Conditions under which a field and other fields in its Borchers class are associated with the same local net are found, in terms of the regularity condition mentioned. (orig.)
Field study evaluation of diffuse ceiling ventilation in classroom during real operating conditions
DEFF Research Database (Denmark)
Kristensen, Martin Heine; Jensen, Jakob Søland; Heiselberg, Per Kvols
2017-01-01
Highlights •Field experimental measurements during real operating conditions. •Evaluation of pressure chamber effect. •Evaluation of displacement effect. •Evaluation of thermal comfort.......Highlights •Field experimental measurements during real operating conditions. •Evaluation of pressure chamber effect. •Evaluation of displacement effect. •Evaluation of thermal comfort....
Nonperturbative scale anomaly and composite operators in gauge field theories
International Nuclear Information System (INIS)
Gusynin, V.P.; Miranskij, V.A.
1987-01-01
In non-asymptotically free gauge theories with a non-trivial ultraviolet fixed point scale symmetry breaking (the scale anomaly) caused by the nonperturbative PCAC dynamics is studied. In the two-loop approximation the analytical expression for the gluon condensate is obtained. It is shown that the form of the anomaly depends on the type of the phase of a theory to which it relates. The hypothesis about the soft behaviour at small distances of composite operators in such theories is confirmed. 14 refs.; 1 fig
A note on the expectation and deviation of physical quantities
International Nuclear Information System (INIS)
Nagasawa, Masao
2009-01-01
By using the function representation of self-adjoint operators, the expectation and variance of physical quantities (self-adjoint operators) are defined, and it is shown that the so-called uncertainty principle does not hold.
The ITER poloidal field configuration and operation scenario
International Nuclear Information System (INIS)
Gribov, Y.; Portone, A.; Mondino, P.L.
1995-01-01
The ITER Poloidal Field (PF) system must satisfy the following requirements. (1) ITER must have a well-controlled, single null divertor magnetic configuration with nominal plasma current 21MA and moderate plasma elongation k95 < 1.65. (2) For a variety of plasma scenarios the ITER PF system must provide: inductive breakdown and start-up in an expanding-aperture limiter configuration near the outboard first wall; an inductive current ramp-up to the nominal plasma current with a reasonable assumption of resistive loss during current ramp-up; a pulse length of 1,000s for ignition and inductively-sustained burn at nominal plasma current; plasma shutdown (following fusion power termination) in a similar contracting-aperture limiter configuration. The present design of the PF system can satisfy the ITER requirements within specified limitations
Field stabilization in superconducting cavities under pulsed operating
International Nuclear Information System (INIS)
Tessier, J.M.
1996-01-01
Within the framework of Tesla linear accelerator project, superconducting cavity battery is used to accelerate electrons and positrons. These cavities require pulsed running and must reach very high accelerating gradients. Under the action of the Lorentz force, the resonance frequency shifts and leaves the band-pass width, which hinders the field from taking its maximal value inside the cavity. The setting of an auto-oscillating loop allows to bring the generator frequency under the control of the cavity frequency. A feedback system is needed to reduce the energy dispersion inside the particle packets. The effects of the mechanical vibrations that disturb the accelerating voltage phase between two impulses are also compensated by a feedback loop. This thesis describes all these phenomena and computes their effects on the energy dispersion of the beam in both cases of relativistic and non-relativistic particles. (A.C.)
Path operator algebras in conformal quantum field theories
International Nuclear Information System (INIS)
Roesgen, M.
2000-10-01
Two different kinds of path algebras and methods from noncommutative geometry are applied to conformal field theory: Fusion rings and modular invariants of extended chiral algebras are analyzed in terms of essential paths which are a path description of intertwiners. As an example, the ADE classification of modular invariants for minimal models is reproduced. The analysis of two-step extensions is included. Path algebras based on a path space interpretation of character identities can be applied to the analysis of fusion rings as well. In particular, factorization properties of character identities and therefore of the corresponding path spaces are - by means of K-theory - related to the factorization of the fusion ring of Virasoro- and W-algebras. Examples from nonsupersymmetric as well as N=2 supersymmetric minimal models are discussed. (orig.)
Problems in operation of gas-oil condensate fields
Energy Technology Data Exchange (ETDEWEB)
Zheltov, Yu V; Martos, V N
1966-12-01
This is a review of various methods used to deplete gas-oil condensate reservoirs. Four depletion techniques are discussed: (1) natural depletion without injection of fluids into the reservoir; (2) depletion accompanied by gas cycling; (3) depletion in which the gas cap is separated from the oil by water injected into the reservoir, a method in which each part of the reservoir is produced essentially independently of the other; and (4) depletion in which reservoir temperature is raised above the cricondentherm point by in-situ combustion, so that gas and oil form a single phase. This method is prospective, and has not been tried in the field. Advantages and disadvantages of each method are discussed. It is concluded that a gas condensate reservoir can be depleted most economically only if some secondary energy is added. (13 refs.)
Polarization operator in quantum electrodynamics with a pair-producing external field
International Nuclear Information System (INIS)
Barashev, V.P.; Shvartsman, Sh.M.; Shabad, A.E.
1986-01-01
Various radiative processes with one-photon initial state are treated in QED with pair-producing external field. It is shown that the probabilities of such processes are expressed in terms of two different polarization operators. For the case of a constant field the polarization operator which is expressed through the so-called causal Green electron function, is calculated. This operator has never been calculated previously. It enters the formula for probability of production of N arbitrary pairs by a photon
Assessing the actions of the farm managers to execute field operations at opportune times
DEFF Research Database (Denmark)
Edwards, Gareth Thomas Charles; Dybro, Niels; Munkholm, Lars Juhl
2016-01-01
Planning agricultural operations requires an understanding of when fields are ready for operations. However determining a field's readiness is a difficult process that can involve large amounts of data and an experienced farm manager. A consequence of this is that operations are often executed when...... fields are unready, or partially unready, which can compromise results incurring environmental impacts, decreased yield and increased operational costs. In order to assess timeliness of operations' execution, a new scheme is introduced to quantify the aptitude of farm managers to plan operations. Two...... parameterise the crop model. The evaluation criteria could be used to identify farm managers who require decisional support when planning operations, or as a means of promoting the use of sustainable farming practices....
Water Treatment Plant Operation. Volume II. A Field Study Training Program.
California State Univ., Sacramento. School of Engineering.
The purpose of this water treatment field study training program is to: (1) develop new qualified water treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…
Water Treatment Plant Operation. Volume I. A Field Study Training Program.
California State Univ., Sacramento. School of Engineering.
The purpose of this water treatment field study training program is to: (1) develop new qualified water treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…
California State Univ., Sacramento. Dept. of Civil Engineering.
The purpose of this wastewater treatment field study training program is to: (1) develop new qualified wastewater treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…
Water Treatment Plant Operation Volume 2. A Field Study Training Program. Revised.
California State Univ., Sacramento. School of Engineering.
The purpose of this water treatment field study training program is to: (1) develop new qualified water treatment plant operators; (2) expand the abilities of existing operators, permitting better service both to employers and public; and (3) prepare operators for civil service and certification examinations (examinations administered by…
Singular Spectrum Near a Singular Point of Friedrichs Model Operators of Absolute Type
International Nuclear Information System (INIS)
Iakovlev, Serguei I.
2006-01-01
In L 2 (R) we consider a family of self adjoint operators of the Friedrichs model: A m =|t| m +V. Here |t| m is the operator of multiplication by the corresponding function of the independent variable t element of R, and (perturbation) is a trace-class integral operator with a continuous Hermitian kernel ν(t,x) satisfying some smoothness condition. These absolute type operators have one singular point of order m>0. Conditions on the kernel ν(t,x) are found guaranteeing the absence of the point spectrum and the singular continuous one of such operators near the origin. These conditions are actually necessary and sufficient. They depend on the finiteness of the rank of a perturbation operator and on the order of singularity. The sharpness of these conditions is confirmed by counterexamples
Studies on the reliability of high-field intra-operative MRI in brain glioma resection
Directory of Open Access Journals (Sweden)
Zhi-jun SONG
2011-07-01
Full Text Available Objective To evaluate the reliability of high-field intra-operative magnetic resonance imaging(iMRI in detecting the residual tumors during glioma resection.Method One hundred and thirty-one cases of brain glioma(69 males and 62 females,aged from 7 to 79 years with mean of 39.6 years hospitalized from Nov.2009 to Aug.2010 were involved in present study.All the patients were evaluated using magnetic resonance imaging(MRI before the operation.The tumors were resected under conventional navigation microscope,and the high-field iMRI was used for all the patients when the operators considered the tumor was satisfactorily resected,while the residual tumor was difficult to detect under the microscope,but resected after being revealed by high-field iMRI.Histopathological examination was performed.The patients without residual tumors recieved high-field MRI scan at day 4 or 5 after operation to evaluate the accuracy of high-field iMRI during operation.Results High quality intra-operative images were obtained by using high-field iMRI.Twenty-eight cases were excluded because their residual tumors were not resected due to their location too close to functional area.Combined with the results of intra-operative histopathological examination and post-operative MRI at the early recovery stage,the sensitivity of high-field iMRI in residual tumor diagnosis was 98.0%(49/50,the specificity was 94.3%(50/53,and the accuracy was 96.1%(99/103.Conclusion High-quality intra-operative imaging could be acquired by high-field iMRI,which maybe used as a safe and reliable method in detecting the residual tumors during glioma resection.
Random operators disorder effects on quantum spectra and dynamics
Aizenman, Michael
2015-01-01
This book provides an introduction to the mathematical theory of disorder effects on quantum spectra and dynamics. Topics covered range from the basic theory of spectra and dynamics of self-adjoint operators through Anderson localization-presented here via the fractional moment method, up to recent results on resonant delocalization. The subject's multifaceted presentation is organized into seventeen chapters, each focused on either a specific mathematical topic or on a demonstration of the theory's relevance to physics, e.g., its implications for the quantum Hall effect. The mathematical chapters include general relations of quantum spectra and dynamics, ergodicity and its implications, methods for establishing spectral and dynamical localization regimes, applications and properties of the Green function, its relation to the eigenfunction correlator, fractional moments of Herglotz-Pick functions, the phase diagram for tree graph operators, resonant delocalization, the spectral statistics conjecture, and rela...
International Nuclear Information System (INIS)
Peterson, Peter Y.; Gallimore, Alec D.; Haas, James M.
2002-01-01
Magnetic field measurements were made in the discharge channel of the 5 kW-class P5 laboratory-model Hall thruster to investigate what effect the Hall current has on the static, applied magnetic field topography. The P5 was operated at 1.6 and 3.0 kW with a discharge voltage of 300 V. A miniature inductive loop probe (B-Dot probe) was employed to measure the radial magnetic field profile inside the discharge channel of the P5 with and without the plasma discharge. These measurements are accomplished with minimal disturbance to thruster operation with the High-speed Axial Reciprocating Probe system. The results of the B-Dot probe measurements indicate a change in the magnetic field topography from that of the vacuum field measurements. The measured magnetic field profiles are then examined to determine the possible nature and source of the difference between the vacuum and plasma magnetic field profiles
Influence of magnetic field on swap operation in Heisenberg XXZ model
Energy Technology Data Exchange (ETDEWEB)
Liu Jia [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China); Zhang Guofeng, E-mail: gf1978zhang@buaa.edu.c [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China); Chen Ziyu [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China)
2009-05-01
Swap operation based on a two-qubit Heisenberg XXZ model under a uniform magnetic field in arbitrary direction and magnitude is investigated. It is shown that swap gate can be implemented on some conditions and its feasibility is established.
Influence of magnetic field on swap operation in Heisenberg XXZ model
International Nuclear Information System (INIS)
Liu Jia; Zhang Guofeng; Chen Ziyu
2009-01-01
Swap operation based on a two-qubit Heisenberg XXZ model under a uniform magnetic field in arbitrary direction and magnitude is investigated. It is shown that swap gate can be implemented on some conditions and its feasibility is established.
Draft Title V Operating Permit: Andeavor Field Services, LLC - Walker Hollow Compressor Station
Draft Title V Operating Permit, statement of basis, public notice bulletin, and the administrative permit docket (application and other supporting documents) for the Draft Part 71 Permit for Andeavor Field Services, LLC - Walker Hollow CS.
Integrated vehicle-based safety systems light-vehicle field operational test key findings report.
2011-01-01
"This document presents key findings from the light-vehicle field operational test conducted as part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of analyses performed by the University of Michigan Transportat...
2010-12-01
"This document presents the methodology and results from the light-vehicle field operational test conducted as part of the Integrated Vehicle-Based Safety Systems program. These findings are the result of analyses performed by the University of Michi...
2009-12-22
This document presents the University of Michigan Transportation Research Institutes plan to : perform analysis of data collected from the light vehicle platform field operational test of the : Integrated Vehicle-Based Safety Systems (IVBSS) progr...
2009-11-23
This document presents the University of Michigan Transportation Research Institutes plan to perform : analysis of data collected from the heavy truck platform field operational test of the Integrated Vehicle- : Based Safety Systems (IVBSS) progra...
Title V Operating Permit: QEP Field Services Company - Wonsits Valley Compressor Station
Response to public comments and the Title V Operating Permit for the QEP Field Services Company, Wonsits Valley Compressor Station, located on the Uintah and Ouray Indian Reservation in Uintah County, Utah.
Title V Operating Permit: QEP Field Services Company - Coyote Wash Compressor Station
Response to public comments and the Title V Operating Permit for the QEP Field Services Company, Coyote Wash Compressor Station, located on the Uintah and Ouray Indian Reservation in Uintah County, Utah.
2006-07-01
This document provides the final report for the evaluation of the USDOT-sponsored Computer-Aided Dispatch Traffic Management Center Integration Field Operations Test in the State of Utah. The document discusses evaluation findings in the followin...
2006-05-01
This document provides the final report for the evaluation of the USDOT-sponsored Computer-Aided Dispatch - Traffic Management Center Integration Field Operations Test in the State of Washington. The document discusses evaluation findings in the foll...
Eigenfunction method and mass operator in the quantum electrodynamics of a constant field
International Nuclear Information System (INIS)
Ritus, V.I.
1978-01-01
A method is presented for the calculation of radiative effects in the quantum electrodynamics of an intense constant field. It is based on the application of the mass operator eigenfunctions and on diagonalization of the operator. A compact expression for the proper value of the electron mass operator in an arbitrary constant field and the corresponding elastic scattering amplitude are found. The imaginary part of the amplitude determines the decay rate of various states of the electron in the field; the real part contains the mass shift and the anomalous magnetic and electric moments as functions of the field and electron momentum. THe anomalous electric moment which arises in a field with a pseudoscalar EH not equal to 0 and the anomalous magnetic moment in an electric field which tends to the double Schwinger value with increase of the field strength are found and investigated in detail as are the mass shift and decay rate of the ground state of an electron in an electric field. In a weak field the mass shift contains the linear with respect to the field modulus classical term which characterizes the effect of acceleration on the structure of electron
Dimension shifting operators and null states in 2D conformally invariant field theories
International Nuclear Information System (INIS)
Gervais, J.L.
1986-01-01
We discuss the existence and properties of differential operators which transform covariant operators into covariant operators of different weights in two-dimensional conformally invariant field theories. We relate them to null states and the vanishing of the Kac determinant in representations of the conformal algebra, and to the existence of differential equations for Green functions of covariant operators. In this framework, we rederive the essential features of our earlier work on dual models with shifted intercept, which in euclidean space-time gives explicit solutions of the conformal bootstrap equations where all operators are marginal. (orig.)
Weisburd, Melvin I.
The Field Operations and Enforcement Manual for Air Pollution Control, Volume III, explains in detail the following: inspection procedures for specific sources, kraft pulp mills, animal rendering, steel mill furnaces, coking operations, petroleum refineries, chemical plants, non-ferrous smelting and refining, foundries, cement plants, aluminum…
Frames, the Loewner order and eigendecomposition for morphological operators on tensor fields
van de Gronde, Jasper; Roerdink, Jos B. T. M.
2014-01-01
Rotation invariance is an important property for operators on tensor fields, but up to now, most methods for morphology on tensor fields had to either sacrifice rotation invariance, or do without the foundation of mathematical morphology: a lattice structure. Recently, we proposed a framework for
International Nuclear Information System (INIS)
Yuan Chang; Li Yong; Ye Zhiqiang
2011-01-01
To realize the coordination in multi-fields' work and information sharing, by applying the method of Enterprise Architecture (EA), the business architecture, functional flow and application architecture of Nuclear Power Plant's operation preparation information integrated platform are designed, which can realize the information sharing and coordination of multi fields. (authors)
The eigenfunction method and the mass operator in intense-field quantum electrodynamics
International Nuclear Information System (INIS)
Ritus, V.I.
1987-01-01
A method is given for calculating radiation effects in constant intense-field quantum electrodynamics; this method is based on the use of the eigenfunctions of the mass operator and diagonalization of the latter. A compact expression is found for the eigenvalue of the mass operator of the electron in a random constant field together with the corresponding elastic scattering amplitude. The anomalous electric moment that arises in the field with a pseudoscalar EH not equal to O is found and investigated in detail together with the anomalous magnetic moment in the electrical field that approaches the double Schwinger value with an increase in the field together with the mass shift and the rate of decay of the ground state of the electron in the electrical field
International Nuclear Information System (INIS)
Raoelina Andriambololona; Ranaivoson, R.T.R; Hanitriarivo, R.; Harison, V.
2014-01-01
We establish equations for scalar and fermion fields using results obtained from a study on a phase space representation of quantum theory that we have performed in a previous work. Our approaches are similar to the historical ones to obtain Klein-Gordon and Dirac equations but the main difference is that ours are based on the use of properties of operators called dispersion-codispersion operators. We begin with a brief recall about the dispersion-codispersion operators. Then, introducing a mass operator with its canonical conjugate coordinate and applying rules of quantization, based on the use of dispersion - codispersion operators , we deduce a second order differential operator relation from the relativistic expression relying energy, momentum and mass. Using Dirac matrices, we derive from this second order differential operator relation a first order one. The application of the second order differential operator relation on a scalar function gives the equation for the scalar field and the use of the first order differential operator relation leads to the equation for fermion field.
On a non-self adjoint eigenfunction expansion
Directory of Open Access Journals (Sweden)
D. Naylor
1984-01-01
Full Text Available This paper develops a formula of inversion for an integral transform similar to that associated with the names of Kontorovich and Lebedev. The kernel involves the Hankel function Hu(1(kr, in which r varies over a truncated infinite interval a≤r0 and the parameter k is complex. This kind of transform is useful in the investigation of functions that satisfy the Helmholtz equation and the condition of radiation.
Self-adjointness of unbounded derivations on C*-algebras
International Nuclear Information System (INIS)
Bratteli, Ola.
1975-02-01
Various criteria on an unbounded derivation on a C*-algebra which ensures that the derivation is the infinitesimal generator of a strongly continuous one-parameter group of *-automorphisms are discussed. Results obtained by R.T. Powers, D.W. Robinson, S. Sakai and the author during the last year are surveyed and systematized. A couple of new results are also included [fr
Continuous spins in 2D gravity: Chiral vertex operators and local fields
International Nuclear Information System (INIS)
Gervais, Jean-Loup; Schnittger, Jens
1994-01-01
We construct the exponentials of the Liouville field with continuous powers within the operator approach. Their chiral decomposition is realized using the explicit Coulomb-gas operators we introduced earlier. From the quantum group viewpoint, they are related to semi-infinite highest- or lowest-weight representations with continuous spins. The Liouville field itself is defined, and the canonical commutation relations are verified, as well as the validity of the quantum Liouville field equations. In a second part, both screening charges are considered. The braiding of the chiral components is derived and shown to agree with an ansatz of a parallel paper of Gervais and Roussel. ((orig.))
International Nuclear Information System (INIS)
Fredenhagen, K.; Joerss, M.
1994-10-01
Starting from a chiral conformal Haag-Kastler net on 2 dimensional Minkowski space we construct associated pointlike localized fields. This amounts to a proof of the existence of operator product expansions. We derive the result in two ways. One is based on the geometrical identification of the modular structure, the other depends on a ''conformal cluster theorem'' of the conformal two-point-functions in algebraic quantum field theory. The existence of the fields then implies important structural properties of the theory, as PCT-invariance, the Bisognano-Wichmann identification of modular operators, Haag duality and additivity. (orig.)
Calibration and characterization of Bayard-Alpert gauges operating in high magnetic fields
International Nuclear Information System (INIS)
Pickles, W.L.; Hunt, A.L.
1985-11-01
Standard Bayard-Alpert gauges have been successfully operated for several months in the 0.3 to 0.7 T magnetic fields near the plasma edge of the Tandem Mirror Experiment-Upgrade (TMX-U). The gauges clearly measure gas pressure and maintain calibration within 10% during operation. The gauge filaments are tungsten and are heated with DC. The gauge housing allows operation in the low density plasma outside the limiter radius by thermalizing the neutral gas that enters the gauge and by preventing plasma from entering the gauge. Changing the orientation of the gauge with respect to the magnetic field changes the gauge calibration, or effective sensitivity, by as much as a factor of 100. Only some orientations of the filament collector plane with respect to the magnetic field direction allow calibrated operation as a pressure gauge. This range of angles is approximately from 20 to 50 degrees. The gauge is oriented to produce the desired sensitivity, then calibrated for the magnetic field effects for that position. The correction to sensitivity for magnet field is not strongly species dependent. The gauge species sensitivities for CH 4 , Xe,and Kr measured in the high magnetic fields were found to be close to the published values measured in no magnetic field
Background independent quantizations-the scalar field: II
International Nuclear Information System (INIS)
Kaminski, Wojciech; Lewandowski, Jerzy; Okolow, Andrzej
2006-01-01
We are concerned with the issue of the quantization of a scalar field in a diffeomorphism invariant manner. We apply the method used in loop quantum gravity. It relies on the specific choice of scalar field variables referred to as the polymer variables. The quantization, in our formulation, amounts to introducing the 'quantum' polymer *-star algebra and looking for positive linear functionals, called states. As assumed in our paper, homeomorphism invariance allows us to derive the complete class of the states. They are determined by the homeomorphism invariant states defined on the CW-complex *-algebra. The corresponding GNS representations of the polymer *-algebra and their self-adjoint extensions are derived, the equivalence classes are found, and invariant subspaces characterized. In part I we outlined those results. Here, we present the technical details
International Nuclear Information System (INIS)
Zolotarev, Vladimir A
2009-01-01
Functional models are constructed for commutative systems {A 1 ,A 2 } of bounded linear non-self-adjoint operators which do not contain dissipative operators (which means that ξ 1 A 1 +ξ 2 A 2 is not a dissipative operator for any ξ 1 , ξ 2 element of R). A significant role is played here by the de Branges transform and the function classes occurring in this context. Classes of commutative systems of operators {A 1 ,A 2 } for which such a construction is possible are distinguished. Realizations of functional models in special spaces of meromorphic functions on Riemann surfaces are found, which lead to reasonable analogues of de Branges spaces on these Riemann surfaces. It turns out that the functions E(p) and E-tilde(p) determining the order of growth in de Branges spaces on Riemann surfaces coincide with the well-known Baker-Akhiezer functions. Bibliography: 11 titles.
Limits on CP-odd four-fermion operators containing the strange quark field
International Nuclear Information System (INIS)
Hamzaoui, C.; Pospelov, M.
1999-01-01
The bounds on the neutron electric dipole moment and T-odd nucleon-nucleon interaction are used to extract the limits on the effective CP-odd four-fermion operators containing a strange quark field. This completes the study of the dim=5,6 CP-odd operators built from light-quark fields. The limits are very strong and comparable to those obtained previously for operators containing up and down flavors. We also analyze the shift of the axionic vacuum, θ eff , induced by four-fermion operators in the presence of the PQ mechanism and conclude that this gives subleading contributions to CP-odd observables as compared with the direct ones. copyright 1999 The American Physical Society
Field-scale operation of methane biofiltration systems to mitigate point source methane emissions
International Nuclear Information System (INIS)
Hettiarachchi, Vijayamala C.; Hettiaratchi, Patrick J.; Mehrotra, Anil K.; Kumar, Sunil
2011-01-01
Methane biofiltration (MBF) is a novel low-cost technique for reducing low volume point source emissions of methane (CH 4 ). MBF uses a granular medium, such as soil or compost, to support the growth of methanotrophic bacteria responsible for converting CH 4 to carbon dioxide (CO 2 ) and water (H 2 O). A field research program was undertaken to evaluate the potential to treat low volume point source engineered CH 4 emissions using an MBF at a natural gas monitoring station. A new comprehensive three-dimensional numerical model was developed incorporating advection-diffusive flow of gas, biological reactions and heat and moisture flow. The one-dimensional version of this model was used as a guiding tool for designing and operating the MBF. The long-term monitoring results of the field MBF are also presented. The field MBF operated with no control of precipitation, evaporation, and temperature, provided more than 80% of CH 4 oxidation throughout spring, summer, and fall seasons. The numerical model was able to predict the CH 4 oxidation behavior of the field MBF with high accuracy. The numerical model simulations are presented for estimating CH 4 oxidation efficiencies under various operating conditions, including different filter bed depths and CH 4 flux rates. The field observations as well as numerical model simulations indicated that the long-term performance of MBFs is strongly dependent on environmental factors, such as ambient temperature and precipitation. - Highlights: → One-dimensional version of the model was used as a guiding tool for designing and operating the MBF. → Mathematical model predicted CH 4 oxidation behaviors of the field MBF with high accuracy i.e. (> 80 %). → Performance of MBF is dependent on ambient temperature and precipitation. - The developed numerical model simulations and field observations for estimating CH 4 oxidation efficiencies under various operating conditions indicate that the long-term performance of MBFs is strongly
Operable Unit 3-13, Group 3, Other Surface Soils (Phase II) Field Sampling Plan
Energy Technology Data Exchange (ETDEWEB)
G. L. Schwendiman
2006-07-27
This Field Sampling Plan describes the Operable Unit 3-13, Group 3, Other Surface Soils, Phase II remediation field sampling activities to be performed at the Idaho Nuclear Technology and Engineering Center located within the Idaho National Laboratory Site. Sampling activities described in this plan support characterization sampling of new sites, real-time soil spectroscopy during excavation, and confirmation sampling that verifies that the remedial action objectives and remediation goals presented in the Final Record of Decision for Idaho Nuclear Technology and Engineering Center, Operable Unit 3-13 have been met.
Energy Technology Data Exchange (ETDEWEB)
Bagrov, V G; Dorofeev, O F; Sokolov, A A; Ternov, I M; Khalilov, V R [Moskovskij Gosudarstvennyj Univ. (USSR)
1975-03-11
When electrons move in a magnetic field, synchrotron radiation gives rise to transitions accompanied by the electron spin reorientation. In this case, it is essential that the transition probability depends on the spin orientation; as a result electron polarization takes place with the spin orientation being predominantly opposite to the direction of the magnetic field. This effect has been called ''radiative self-polarization of electrons''. The present work is concerned with the question how the choice of the spin operator will affect the self-polarization degree and relaxation time. The problem has been solved for a vector spin operator.
Bleacher, Jacob E.; Hurtado, J. M., Jr.; Meyer, J. A.
2012-01-01
Desert Research and Technology Studies (DRATS) is a multi-year series of NASA tests that deploy planetary surface hardware and exercise mission and science operations in difficult conditions to advance human and robotic exploration capabilities. DRATS 2011 (Aug. 30-Sept. 9, 2011) tested strategies for human exploration of microgravity targets such as near-Earth asteroids (NEAs). Here we report the crew perspective on the impact of simulated microgravity operations on our capability to conduct field geology.
Comment on 'New ansatz for metric operator calculation in pseudo-Hermitian field theory'
International Nuclear Information System (INIS)
Bender, Carl M.; Benincasa, Gregorio; Jones, H. F.
2009-01-01
In a recent Brief Report by Shalaby, a new first-order perturbative calculation of the metric operator for an iφ 3 scalar field theory is given. It is claimed that the incorporation of derivative terms in the ansatz for the metric operator results in a local solution, in contrast to the nonlocal solution previously obtained by Bender, Brody, and Jones. Unfortunately, Shalaby's calculation is not valid because of sign errors.
Regularization in Hilbert space under unbounded operators and general source conditions
International Nuclear Information System (INIS)
Hofmann, Bernd; Mathé, Peter; Von Weizsäcker, Heinrich
2009-01-01
The authors study ill-posed equations with unbounded operators in Hilbert space. This setup has important applications, but only a few theoretical studies are available. First, the question is addressed and answered whether every element satisfies some general source condition with respect to a given self-adjoint unbounded operator. This generalizes a previous result from Mathé and Hofmann (2008 Inverse Problems 24 015009). The analysis then proceeds to error bounds for regularization, emphasizing some specific points for regularization under unbounded operators. The study finally reviews two examples within the light of the present study, as these are fractional differentiation and some Cauchy problems for the Helmholtz equation, both studied previously and in more detail by U Tautenhahn and co-authors
Realization of vector fields for quantum groups as pseudodifferential operators on quantum spaces
International Nuclear Information System (INIS)
Chu, Chong-Sun; Zumino, B.
1995-01-01
The vector fields of the quantum Lie algebra are described for the quantum groups GL q (n), SL q (N) and SO q (N) as pseudodifferential operators on the linear quantum spaces covariant under the corresponding quantum group. Their expressions are simple and compact. It is pointed out that these vector fields satisfy certain characteristic polynomial identities. The real forms SU q (N) and SO q (N,R) are discussed in detail
Energy Technology Data Exchange (ETDEWEB)
Baklid, A.; Apeland, O. J.; Teigen, A. S. [Statoil (Norway)
1998-12-31
Conventional tubing deployed electrical submersible pump (ESP) was the original choice as the artificial lift method for the Yme field offshore Norway. Several operational problems experienced over the past two years, such as formation damage, complicated and costly workovers and limited access to the reservoir, combined with revised field requirements and a reevaluation of artificial lift methods resulted in a change in completion philosophy. Following these reassessments coiled tubing ESPs utilizing internal power cable were installed and became the preferred method. This paper provides an assessment of the value of installing CT-ESP in a live well, and describes the system design for a true underbalanced CT-ESP installation. Well control and barrier philosophy during installation, production and workover mode is also evaluated. 2 refs., 3 tabs., 5 figs.
Entanglement between smeared field operators in the Klein-Gordon vacuum
International Nuclear Information System (INIS)
Zych, Magdalena; Costa, Fabio; Kofler, Johannes; Brukner, Caslav
2010-01-01
Quantum field theory is the application of quantum physics to fields. It provides a theoretical framework widely used in particle physics and condensed matter physics. One of the most distinct features of quantum physics with respect to classical physics is entanglement or the existence of strong correlations between subsystems that can even be spacelike separated. In quantum fields, observables restricted to a region of space define a subsystem. While there are proofs on the existence of local observables that would allow a violation of Bell's inequalities in the vacuum states of quantum fields as well as some explicit but technically demanding schemes requiring an extreme fine-tuning of the interaction between the fields and detectors, an experimentally accessible entanglement witness for quantum fields is still missing. Here we introduce smeared field operators which allow reducing the vacuum to a system of two effective bosonic modes. The introduction of such collective observables is motivated by the fact that no physical probe has access to fields in single spatial (mathematical) points but rather smeared over finite volumes. We first give explicit collective observables whose correlations reveal vacuum entanglement in the Klein-Gordon field. We then show that the critical distance between the two regions of space above which two effective bosonic modes become separable is of the order of the Compton wavelength of the particle corresponding to the massive Klein-Gordon field.
Directory of Open Access Journals (Sweden)
Y. L. Li
2013-01-01
Full Text Available Cropping fields often have well-defined poor-performing patches due to spatial and temporal variability. In an attempt to increase crop performance on poor patches, spatially selective field operations may be performed by agricultural robotics to apply additional inputs with targeted requirements. This paper addresses the route planning problem for an agricultural robot that has to treat some poor-patches in a field with row crops, with respect to the minimization of the total non-working distance travelled during headland turnings and in-field travel distance. The traversal of patches in the field is expressed as the traversal of a mixed weighted graph, and then the problem of finding an optimal patch sequence is formulated as an asymmetric traveling salesman problem and solved by the partheno-genetic algorithm. The proposed method is applied on a cropping field located in Northwestern China. Research results show that by using optimum patch sequences, the total non-working distance travelled during headland turnings and in-field travel distance can be reduced. But the savings on the non-working distance inside the field interior depend on the size and location of patches in the field, and the introduction of agricultural robotics is beneficial to increase field efficiency.
Energy Technology Data Exchange (ETDEWEB)
Li, Y. L.; Yi, S. P.
2013-05-01
Cropping fields often have well-defined poor-performing patches due to spatial and temporal variability. In an attempt to increase crop performance on poor patches, spatially selective field operations may be performed by agricultural robotics to apply additional inputs with targeted requirements. This paper addresses the route planning problem for an agricultural robot that has to treat some poor-patches in a field with row crops, with respect to the minimization of the total non-working distance travelled during headland turnings and in-field travel distance. The traversal of patches in the field is expressed as the traversal of a mixed weighted graph, and then the problem of finding an optimal patch sequence is formulated as an asymmetric traveling salesman problem and solved by the parthenogenetic algorithm. The proposed method is applied on a cropping field located in Northwestern China. Research results show that by using optimum patch sequences, the total non-working distance travelled during headland turnings and in-field travel distance can be reduced. But the savings on the non-working distance inside the field interior depend on the size and location of patches in the field, and the introduction of agricultural robotics is beneficial to increase field efficiency. (Author) 21 refs.
Renormalization Group Equations of d=6 Operators in the Standard Model Effective Field Theory
CERN. Geneva
2015-01-01
The one-loop renormalization group equations for the Standard Model (SM) Effective Field Theory (EFT) including dimension-six operators are calculated. The complete 2499 × 2499 one-loop anomalous dimension matrix of the d=6 Lagrangian is obtained, as well as the contribution of d=6 operators to the running of the parameters of the renormalizable SM Lagrangian. The presence of higher-dimension operators has implications for the flavor problem of the SM. An approximate holomorphy of the one-loop anomalous dimension matrix is found, even though the SM EFT is not a supersymmetric theory.
Robotics and tele-operation technology for applications in nuclear fields
International Nuclear Information System (INIS)
Kosuge, Kazuhiro; Hirata, Yasuhisa; Takeo, Koji
2002-01-01
In this article, we introduce available robotics and tele-operation technology for applications in Nuclear Fields. First, robotics technology for manipulation of a large object is introduced which has been experimentally applied to ITER Maintenance Robot. Then, transportation technology of a large object by multiple mobile robots is reviewed. At last, recent tele-operation technologies and a prototype tele-operation system, referred to as VISIT (Visual Interface System for Interactive Task-execution), is introduced. Several experimental results are also introduced. (author)
Covariance operator of functional measure in P(φ)2-quantum field theory
International Nuclear Information System (INIS)
Lobanov, Yu.Yu.; Zhidkov, E.P.
1988-01-01
Functional integration measure in the Euclidean quantum field theory with polynomial interactions of boson fields with zero spin in two-dimensional space-time is investigated. The representation for the kernal of the measure covariance operator is obtained in the form of expansion over the eigenfunctions of some boundary problem for the heat equation. Two cases of the integration domains with different configurations are considered. Some trends and perspectives of employing the functional integration method in quantum field theory are also discussed. 43 refs
Low-derivative operators of the Standard Model effective field theory via Hilbert series methods
Energy Technology Data Exchange (ETDEWEB)
Lehman, Landon; Martin, Adam [Department of Physics, University of Notre Dame,Nieuwland Science Hall, Notre Dame, IN 46556 (United States)
2016-02-12
In this work, we explore an extension of Hilbert series techniques to count operators that include derivatives. For sufficiently low-derivative operators, we conjecture an algorithm that gives the number of invariant operators, properly accounting for redundancies due to the equations of motion and integration by parts. Specifically, the conjectured technique can be applied whenever there is only one Lorentz invariant for a given partitioning of derivatives among the fields. At higher numbers of derivatives, equation of motion redundancies can be removed, but the increased number of Lorentz contractions spoils the subtraction of integration by parts redundancies. While restricted, this technique is sufficient to automatically recreate the complete set of invariant operators of the Standard Model effective field theory for dimensions 6 and 7 (for arbitrary numbers of flavors). At dimension 8, the algorithm does not automatically generate the complete operator set; however, it suffices for all but five classes of operators. For these remaining classes, there is a well defined procedure to manually determine the number of invariants. Assuming our method is correct, we derive a set of 535 dimension-8 N{sub f}=1 operators.
Low-derivative operators of the Standard Model effective field theory via Hilbert series methods
International Nuclear Information System (INIS)
Lehman, Landon; Martin, Adam
2016-01-01
In this work, we explore an extension of Hilbert series techniques to count operators that include derivatives. For sufficiently low-derivative operators, we conjecture an algorithm that gives the number of invariant operators, properly accounting for redundancies due to the equations of motion and integration by parts. Specifically, the conjectured technique can be applied whenever there is only one Lorentz invariant for a given partitioning of derivatives among the fields. At higher numbers of derivatives, equation of motion redundancies can be removed, but the increased number of Lorentz contractions spoils the subtraction of integration by parts redundancies. While restricted, this technique is sufficient to automatically recreate the complete set of invariant operators of the Standard Model effective field theory for dimensions 6 and 7 (for arbitrary numbers of flavors). At dimension 8, the algorithm does not automatically generate the complete operator set; however, it suffices for all but five classes of operators. For these remaining classes, there is a well defined procedure to manually determine the number of invariants. Assuming our method is correct, we derive a set of 535 dimension-8 N_f=1 operators.
Isomorphism of critical and off-critical operator spaces in two-dimensional quantum field theory
Energy Technology Data Exchange (ETDEWEB)
Delfino, G. [International School of Advanced Studies (SISSA), Trieste (Italy)]|[INFN sezione di Trieste (Italy); Niccoli, G. [Univ. de Cergy-Pontoise (France). LPTM
2007-12-15
For the simplest quantum field theory originating from a non-trivial fixed point of the renormalization group, the Lee-Yang model, we show that the operator space determined by the particle dynamics in the massive phase and that prescribed by conformal symmetry at criticality coincide. (orig.)
Involutive distributions of operator-valued evolutionary vector fields and their affine geometry
Kiselev, A.V.; van de Leur, J.W.
2010-01-01
We generalize the notion of a Lie algebroid over infinite jet bundle by replacing the variational anchor with an N-tuple of differential operators whose images in the Lie algebra of evolutionary vector fields of the jet space are subject to collective commutation closure. The linear space of such
16 CFR 1000.21 - Office of Compliance and Field Operations.
2010-01-01
... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Office of Compliance and Field Operations. 1000.21 Section 1000.21 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL COMMISSION... addressed through rulemaking or voluntary standards. The Office develops surveillance strategies and...
DEFF Research Database (Denmark)
Berning, Torsten; Odgaard, Madeleine; Kær, Søren Knudsen
2011-01-01
Fuel cell operation on dry reactant gases under low stoichiometry conditions employing the interdigitated flow field is investigated using a multi-fluid model. It is assumed that the MEA contains a water uptake layer which facilitates water absorption to the membrane and hence prevents the anode...
A cost prediction model for machine operation in multi-field production systems
Directory of Open Access Journals (Sweden)
Alessandro Sopegno
Full Text Available ABSTRACT Capacity planning in agricultural field operations needs to give consideration to the operational system design which involves the selection and dimensioning of production components, such as machinery and equipment. Capacity planning models currently onstream are generally based on average norm data and not on specific farm data which may vary from year to year. In this paper a model is presented for predicting the cost of in-field and transport operations for multiple-field and multiple-crop production systems. A case study from a real production system is presented in order to demonstrate the model’s functionalities and its sensitivity to parameters known to be somewhat imprecise. It was shown that the proposed model can provide operation cost predictions for complex cropping systems where labor and machinery are shared between the various operations which can be individually formulated for each individual crop. By so doing, the model can be used as a decision support system at the strategic level of management of agricultural production systems and specifically for the mid-term design process of systems in terms of labor/machinery and crop selection conforming to the criterion of profitability.
Towards Large-area Field-scale Operational Evapotranspiration for Water Use Mapping
Senay, G. B.; Friedrichs, M.; Morton, C.; Huntington, J. L.; Verdin, J.
2017-12-01
Field-scale evapotranspiration (ET) estimates are needed for improving surface and groundwater use and water budget studies. Ideally, field-scale ET estimates would be at regional to national levels and cover long time periods. As a result of large data storage and computational requirements associated with processing field-scale satellite imagery such as Landsat, numerous challenges remain to develop operational ET estimates over large areas for detailed water use and availability studies. However, the combination of new science, data availability, and cloud computing technology is enabling unprecedented capabilities for ET mapping. To demonstrate this capability, we used Google's Earth Engine cloud computing platform to create nationwide annual ET estimates with 30-meter resolution Landsat ( 16,000 images) and gridded weather data using the Operational Simplified Surface Energy Balance (SSEBop) model in support of the National Water Census, a USGS research program designed to build decision support capacity for water management agencies and other natural resource managers. By leveraging Google's Earth Engine Application Programming Interface (API) and developing software in a collaborative, open-platform environment, we rapidly advance from research towards applications for large-area field-scale ET mapping. Cloud computing of the Landsat image archive combined with other satellite, climate, and weather data, is creating never imagined opportunities for assessing ET model behavior and uncertainty, and ultimately providing the ability for more robust operational monitoring and assessment of water use at field-scales.
Studies of IBL wire bonds operation in a ATLAS-like magnetic field.
Alvarez Feito, D; Mandelli, B
2015-01-01
At the Large Hadron Collider (LHC) experiments, most of silicon detectors use wire bonds to connect front-end chips and sensors to circuit boards for the data and service trans- missions. These wire bonds are operated in strong magnetic field environments and if time varying currents pass through them with frequencies close to their mechanical resonance frequency, strong resonant oscillations may occur. Under certain conditions, this effect can lead to fatigue stress and eventually breakage of wire bonds. During the first LHC Long Shutdown, the ATLAS Pixel Detector has been upgraded with the addition of a fourth innermost layer, the Insertable B-Layer (IBL), which has more than 50000 wire bonds operated in the ATLAS 2 T magnetic field. The results of systematic studies of operating wire bonds under IBL-like conditions are presented. Two different solutions have been investigated to minimize the oscillation amplitude of wire bonds.
International Nuclear Information System (INIS)
Sasaki, Ryu; Yamanaka, Itaru
1987-01-01
The quantum version of an infinite set of polynomial conserved quantities of a class of soliton equations is discussed from the point of view of naive continuum field theory. By using techniques of two dimensional field theories, we show that an infinite set of quantum commuting operators can be constructed explicitly from the knowledge of its classical counterparts. The quantum operators are so constructed as to coincide with the classical ones in the ℎ → 0 limit (ℎ; Planck's constant divided by 2π). It is expected that the explicit forms of these operators would shed some light on the structure of the infinite dimensional Lie algebras which underlie a certain class of quantum integrable systems. (orig.)
Study of operational parameters on the performance of micro PEMFCs with different flow fields
International Nuclear Information System (INIS)
Hsieh, S.-S.; Yang, S.-H.; Kuo, J.-K.; Huang, C.-F.; Tsai, H.-H.
2006-01-01
The effects of different operating parameters on micro PEMFC performances were experimentally studied for three different flow field configurations (interdigitated, mesh, and serpentine). Experiments with different cell operating temperatures and different backpressures on the H 2 flow channels, as well as various combinations of these parameters, have been conducted for three different flow geometries. The micro PEMFCs were designed and fabricated inhouse through a deep UV lithography technique and the SU-8 photoresist was used as microstructure material for the fuel cell flow field plates. Results are presented in the form of polarization VI curves and PI curves under different operating conditions. The possible transport mechanisms associated with the parametric effects were discussed. In addition, it was found that among the three flow patterns considered, significant improvements can be reached with a specified flow geometry
International Nuclear Information System (INIS)
Sasaki, Ryu; Yamanaka, Itaru.
1986-08-01
The quantum version of an infinite set of polynomial conserved quantities of a class of soliton equations is discussed from the point of view of naive continuum field theory. By using techniques of two dimensional field theories, we show that an infinite set of quantum commuting operators can be constructed explicitly from the knowledge of its classical counterparts. The quantum operators are so constructed as to coincide with the classical ones in the ℎ → 0 limit (ℎ; Planck's constant divided by 2π). It is expected that the explicit forms of these operators would shed some light on the structure of the infinite dimensional Lie algebras which underlie certain class of quantum integrable systems. (author)
DEFF Research Database (Denmark)
Partanen, Mikko; Häyrynen, Teppo; Tulkki, Jukka
2015-01-01
We have recently developed a quantized fluctuational electrodynamics (QFED) formalism to describe the quantum aspects of local thermal balance formation and to formulate the electromagnetic field ladder operators so that they no longer exhibit the anomalies reported for resonant structures. Here we...... show how the QFED can be used to resolve between the left and right propagating fields to bridge the QFED and the quantum optical input-output relations commonly used to describe selected quantum aspects of resonators. The generalized model introduces a density of states concept describing interference...... effects, which is instrumental in allowing an unambiguous separation of the fields and related quantum operators into left and right propagating parts. In addition to providing insight on the quantum treatment of interference, our results also provide the conclusive resolution of the long-standing enigma...
International Nuclear Information System (INIS)
Luescher, M.
1975-11-01
Let phi 1 (x) and phi 2 (y) be two local fields in a conformal quantum field theory (CQFT) in two-dimensional spacetime. It is then shown that the vector-valued distribution phi 1 (x) phi 2 (y) /0 > is a boundary value of a vector-valued holomorphic function which is defined on a large conformally invariant domain. By group theoretical arguments alone it is proved that phi 1 (x) phi 2 (y) /0 > can be expanded into conformal partial waves. These have all the properties of a global version of Wilson's operator product expansions when applied to the vacuum state /0 >. Finally, the corresponding calculations are carried out more explicitly in the Thirring model. Here, a complete set of local conformally covariant fields is found, which is closed under vacuum expansion of any two of its elements (a vacuum expansion is an operator product expansion applied to the vacuum). (orig.) [de
Use of real-time tools to support field operations of NSF's Lower Atmosphere Observing Facilities
Daniels, M.; Stossmeister, G.; Johnson, E.; Martin, C.; Webster, C.; Dixon, M.; Maclean, G.
2012-12-01
NCAR's Earth Observing Laboratory (EOL) operates Lower Atmosphere Observing Facilities (LAOF) for the scientific community, under sponsorship of the National Science Foundation. In order to obtain the highest quality dataset during field campaigns, real-time decision-making critically depends on the availability of timely data and reliable communications between field operations staff and instrument operators. EOL incorporates the latest technologies to monitor the health of instrumentation, facilitate remote operations of instrumentation and keep project participants abreast of changing conditions in the field. As the availability of bandwidth on mobile communication networks and the capabilities of their associated devices (smart phone, tablets, etc.) improved, so has the ability of researchers to respond to rapidly changing conditions and coordinate ever more detailed measurements from multiple remote fixed, portable and airborne platforms. This presentation will describe several new tools that EOL is making available to project investigators and how these tools are being used in a mobile computing environment to support enhanced data collection during field campaigns. LAOF platforms such as radars, aircraft, sondes, balloons and surface stations all rely on displays of real-time data for their operations. Data from sondes are ingested into the Global Telecommunications System (GTS) for assimilation into regional forecasting models that help guide project operations. Since many of EOL's projects occur around the globe and at the same time instrument complexity has increased, automated monitoring of instrumentation platforms and systems has become essential. Tools are being developed to allow remote instrument control of our suite of observing systems where feasible. The Computing, Data and Software (CDS) Facility of EOL develops and supports a Field Catalog used in field campaigns for nearly two decades. Today, the Field Catalog serves as a hub for the
On the solution of nonlinear differential equations over the field of Mikusinski operators
International Nuclear Information System (INIS)
Sharkawi, I.E.; El-Sabagh, M.A.
1983-08-01
The nonlinear differential equation X'(lambda)+a(lambda)X(lambda)=sb(lambda)Xsup(n+1)(lambda) with the initial condition X(0)=I, over the field of Mikusinski operators [Mikusinski, J. Operational Calculus, Pergamon Press (1957)] is discussed, where a(lambda) and b(lambda) are continuous numerical functions, s is the operator of differentiation, and I is the unit operator. A solution is constructed of the following form: X(lambda)=F(lambda) ([tsup((1/n)-1)]/[GAMMA(1/n)(ng(lambda))sup(1/n)])exp(t/(ng(lambda))), where F(lambda)=exp(-integ 0 sup(lambda)a(lambda)d(lambda) and g(lambda)=integ 0 sup(lambda)[b(lambda)exp(n integ 0 sup(lambda)a(lambda))]dlambda are numerical functions
International Nuclear Information System (INIS)
Kinoshita, Takehiro; Fujiyama, Shinya; Idogaki, Toshihiro; Tokita, Masahiko
2009-01-01
The non-equilibrium phase transition in a ferromagnetic Ising model is investigated by use of a new type of effective field theory (EFT) which correctly accounts for all the single-site kinematic relations by differential operator technique. In the presence of a time dependent oscillating external field, with decrease of the temperature the system undergoes a dynamic phase transition, which is characterized by the period averaged magnetization Q, from a dynamically disordered state Q = 0 to the dynamically ordered state Q ≠ 0. The results of the dynamic phase transition point T c determined from the behavior of the dynamic magnetization and the Liapunov exponent provided by EFT are improved than that of the standard mean field theory (MFT), especially for the one dimensional lattice where the standard MFT gives incorrect result of T c = 0 even in the case of zero external field.
The space-time operator product expansion in string theory duals of field theories
International Nuclear Information System (INIS)
Aharony, Ofer; Komargodski, Zohar
2008-01-01
We study the operator product expansion (OPE) limit of correlation functions in field theories which possess string theory duals, from the point of view of the string worldsheet. We show how the interesting ('single-trace') terms in the OPE of the field theory arise in this limit from the OPE of the worldsheet theory of the string dual, using a dominant saddle point which appears in computations of worldsheet correlation functions in the space-time OPE limit. The worldsheet OPE generically contains only non-physical operators, but all the non-physical contributions are resummed by the saddle point to a contribution similar to that of a physical operator, which exactly matches the field theory expectations. We verify that the OPE limit of the worldsheet theory does not have any other contributions to the OPE limit of space-time correlation functions. Our discussion is completely general and applies to any local field theory (conformal at high energies) that has a weakly coupled string theory dual (with arbitrary curvature). As a first application, we compare our results to a proposal of R. Gopakumar for the string theory dual of free gauge theories
Directory of Open Access Journals (Sweden)
Kaska Serge C
2010-12-01
Full Text Available Abstract Background Intra-operative fluoroscopy for orthopaedic procedures frequently involves imaging in the horizontal plane, which requires the lower portion of the C-arm (x-ray tube to be rotated from an unsterile zone (beneath the table into the sterile field. To protect the integrity of the sterile field the C-arm must be draped repeatedly throughout the surgical case. The current, un-standardized, practice employs draping procedures which violate the Association of peri-Operative Registered Nurses (AORN Standards and Recommended Practices, waste time and material, and pose an increased risk for surgical site infection. Presentation of the hypothesis Use of a novel sterile C-arm drape (C-armor that maintains the integrity of the sterile field, will improve operating room efficiency and reduce surgical site infection risk factors. This reduction in risk factors may potentially reduce surgical site infections in orthopaedic surgical cases requiring repeated horizontal x-ray imaging. Testing the Hypothesis Savings in time and material and the reduction in surgical site infection risk factors afforded by using C-armor are intuitive to those skilled in the practice of orthopaedic surgery. Testing for a reduction in the number of microorganisms introduced to the surgical site by improved C-arm draping would be challenging due to the multiple confounding factors during a surgical operation. Determination of an absolute reduction in surgical site infections may be possible, but will require accounting for many confounding variables and a large study sample in order to achieve statistical significance. Implications of the Hypothesis Improved intraoperative workflow, healthcare savings and a reduction in surgical site infection risk factors will be achieved by utilizing a standardized and safe method of sterile field maintenance during intra-operative horizontal plane fluoroscopy.
Liao, Yi; Ma, Xiao-Dong
2018-03-01
We study two aspects of higher dimensional operators in standard model effective field theory. We first introduce a perturbative power counting rule for the entries in the anomalous dimension matrix of operators with equal mass dimension. The power counting is determined by the number of loops and the difference of the indices of the two operators involved, which in turn is defined by assuming that all terms in the standard model Lagrangian have an equal perturbative power. Then we show that the operators with the lowest index are unique at each mass dimension d, i.e., (H † H) d/2 for even d ≥ 4, and (LT∈ H)C(LT∈ H) T (H † H)(d-5)/2 for odd d ≥ 5. Here H, L are the Higgs and lepton doublet, and ∈, C the antisymmetric matrix of rank two and the charge conjugation matrix, respectively. The renormalization group running of these operators can be studied separately from other operators of equal mass dimension at the leading order in power counting. We compute their anomalous dimensions at one loop for general d and find that they are enhanced quadratically in d due to combinatorics. We also make connections with classification of operators in terms of their holomorphic and anti-holomorphic weights. Supported by the National Natural Science Foundation of China under Grant Nos. 11025525, 11575089, and by the CAS Center for Excellence in Particle Physics (CCEPP)
Deygout, François; Auburtin, Guy
2015-03-01
Variability in occupational exposure levels to bitumen emissions has been observed during road paving operations. This is due to recurrent field factors impacting the level of exposure experienced by workers during paving. The present study was undertaken in order to quantify the impact of such factors. Pre-identified variables currently encountered in the field were monitored and recorded during paving surveys, and were conducted randomly covering current applications performed by road crews. Multivariate variance analysis and regressions were then used on computerized field data. The statistical investigations were limited due to the relatively small size of the study (36 data). Nevertheless, the particular use of the step-wise regression tool enabled the quantification of the impact of several predictors despite the existing collinearity between variables. The two bitumen organic fractions (particulates and volatiles) are associated with different field factors. The process conditions (machinery used and delivery temperature) have a significant impact on the production of airborne particulates and explain up to 44% of variability. This confirms the outcomes described by previous studies. The influence of the production factors is limited though, and should be complemented by studying factors involving the worker such as work style and the mix of tasks. The residual volatile compounds, being part of the bituminous binder and released during paving operations, control the volatile emissions; 73% of the encountered field variability is explained by the composition of the bitumen batch. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Study of the performance of HPGe detectors operating in very high magnetic fields
International Nuclear Information System (INIS)
Agnello, M.; Botta, E.; Bressani, T.; Bruschi, M.; Bufalino, S.; De Napoli, M.; Feliciello, A.; Fontana, A.; Giacobbe, B.; Lavezzi, L.; Raciti, G.; Rapisarda, E.; Rotondi, A.; Sbarra, C.; Sfienti, C.; Zoccoli, A.
2009-01-01
A new generation of high-resolution hypernuclear γ-spectroscopy experiments using high-purity germanium (HPGe) detectors is presently designed for the FINUDA spectrometer at DAΦNE, the Frascati Φ-factory, and for PANDA, the p-p-bar hadron spectrometer at the future FAIR facility. In both spectrometers the HPGe detectors have to be operated in strong magnetic fields. In this paper we report on a series of measurements performed on a HPGe detector inserted in a magnetic field of intensity up to 2.5 T, the highest ever reached for operations with a HPGe, and with different orientations of the detector's axis with respect to field direction. A significant worsening of the energy resolution was found, but with a moderate loss of the efficiency. The most relevant features of the peak shapes, described by bi-Gaussian functions, are parametrized in terms of field intensity and energy: this allows to correct the spectra measured in magnetic field and to recover the energy resolution almost completely.
Low-temperature DC-contact piezoelectric switch operable in high magnetic fields
Kaltenbacher, T; Doser, M; Kellerbauer, A; Pribyl, W
2013-01-01
A piezoelectric single-pole single-throw (SPST) switch has been developed, since there is no satisfying commercial low-resistance, high current DC-contact RF switch available which is operable at 4.2K and in a high magnetic field of at least 0.5T. This piezoelectric switch shows very low insertion loss of less than -0.1dB within a bandwidth of 100MHz when operated at 4.2K. The switch could also be used to mechanically disconnect and connect electrodes or electrical circuits from one another.
Low-temperature DC-contact piezoelectric switch operable in high magnetic fields
Energy Technology Data Exchange (ETDEWEB)
Kaltenbacher, Thomas, E-mail: thomas.kaltenbacher@cern.ch [Physics and Accelerator Departments, CERN, 1211 Geneva 23 (Switzerland); Institute of Electronics, Graz University of Technology, Inffeldgasse 12, 8010 Graz (Austria); Caspers, Fritz; Doser, Michael [Physics and Accelerator Departments, CERN, 1211 Geneva 23 (Switzerland); Kellerbauer, Alban [Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, 69117 Heidelberg (Germany); Pribyl, Wolfgang [Institute of Electronics, Graz University of Technology, Inffeldgasse 12, 8010 Graz (Austria)
2013-11-21
A piezoelectric single-pole single-throw (SPST) switch has been developed, since there is no satisfying commercial low-resistance, high current DC-contact RF switch available which is operable at 4.2 K and in a high magnetic field of at least 0.5 T. This piezoelectric switch shows very low insertion loss of less than −0.1 dB within a bandwidth of 100 MHz when operated at 4.2 K. The switch could also be used to mechanically disconnect and connect electrodes or electrical circuits from one another.
Thermo Wigner operator in thermo field dynamics: its introduction and application
International Nuclear Information System (INIS)
Fan Hongyi; Jiang Nianquan
2008-01-01
Because in thermo-field dynamics (TFD) the thermo-operator has a neat expression in the thermo-entangled state representation, we need to introduce the thermo-Wigner operator (THWO) in the same representation. We derive the THWO in a direct way, which brings much conveniece to calculating the Wigner functions of thermo states in TFD. We also discuss the condition for existence of a wavefunction corresponding to a given Wigner function in the context of TFD by using the explicit form of the THWO.
Operational integrity using field buses; Integridade operacional utilizando barramentos de campo
Energy Technology Data Exchange (ETDEWEB)
Hennig, Carlos Henrique [Coester Automacao S.A., Sao Leopoldo, RS (Brazil)
2004-07-01
The device information is collected using standardized Filed Buses with high data transmission capacity, which allows the analysis of his operational status in real time. The quantity of information generated by the devices for the maintenance area is increasing and this data quantity transferred through the field bus should not interfere in the network performance to the point of degrade his control function. In this way, is presented a technique that can be used in different protocols, which allow sending of maintenance data using a small band of the communication channel. Operational integrity can be achieved using predictive maintenance techniques based on the collected data. (author)
Possible classification of the methods of operational research applicable in the field of defense
Directory of Open Access Journals (Sweden)
Mučibabić Spasoje
2006-01-01
Full Text Available The overall dynamic development of operational research in various fields of human activities urges the need for a clearer and mathematically more explicit classification of its methods. This need is also very urgent in the field of defense, particularly because of the complications of modern conflicts, as well as of new security requirements. One of the possible classifications of methods based on the theory of games as a mathematical model for solving conflict situations is presented in this paper. The connections between methods and their mathematical description are underlined.
Probing organic field effect transistors in situ during operation using SFG.
Ye, Hongke; Abu-Akeel, Ashraf; Huang, Jia; Katz, Howard E; Gracias, David H
2006-05-24
In this communication, we report results obtained using surface-sensitive IR+Visible Sum Frequency Generation (SFG) nonlinear optical spectroscopy on interfaces of organic field effect transistors during operation. We observe remarkable correlations between trends in the surface vibrational spectra and electrical properties of the transistor, with changes in gate voltage (VG). These results suggest that field effects on electronic conduction in thin film organic semiconductor devices are correlated to interfacial nonlinear optical characteristics and point to the possibility of using SFG spectroscopy to monitor electronic properties of OFETs.
International Nuclear Information System (INIS)
Obada, A.S.F.; Mahran, M.H.
1982-08-01
The consequences of including magnetic-dipole contributions, besides the electric-dipole, are considered in the operators for the radiation field. The Bloch equations which describe the two-level atom operators are modified. These equations together with the field operators are discussed, and the contributions are manifested. The spectrum for spontaneous emission and a generalized dynamical Stark effect are obtained. Rabi frequency is modified. (author)
Regional long-term co-operation in the field of nuclear and radiation emergency preparedness
International Nuclear Information System (INIS)
Sladek, V.; Metke, E.; Janko, K.; Hohenberg, J. K.; Hofer, P.
2004-01-01
Emergency preparedness is generally covered by methodical and coordinative activities of the International Atomic Energy Agency (IAEA) in Member States of the IAEA and by the European Commission (EC) in EU Member and EU Accession Countries. However, the regional harmonisation of emergency arrangements is an important trend of emergency preparedness. The present paper gives a couple of illustrative examples for a regional co-operation in the field of emergency preparedness in Central Europe and an overview on international exercises in this region. The penultimate section contains an outlook on future activities regarding regional co-operation in Central Europe. The following topics have been suggested inter alia: the harmonisation of intervention criteria and countermeasures, co-ordination in the field of information of the public, comprehensive bi lateral and multilateral exercises, exchange of experts between the national nuclear emergency centres and inter-comparison calculations of the computer codes. (authors)
Rosetta: an operator basis translator for standard model effective field theory
Energy Technology Data Exchange (ETDEWEB)
Falkowski, Adam [Laboratoire de Physique Théorique, Bat. 210, Université Paris-Sud, 91405, Orsay (France); Fuks, Benjamin [Département Recherches Subatomiques, Institut Pluridisciplinaire Hubert Curien, Université de Strasbourg/CNRS-IN2P3, 23 rue du Loess, 67037, Strasbourg (France); Mawatari, Kentarou [Theoretische Natuurkunde and IIHE/ELEM, Vrije Universiteit Brussel, and International Solvay Institutes, Pleinlaan 2, 1050, Brussels (Belgium); Mimasu, Ken, E-mail: k.mimasu@sussex.ac.uk [Department of Physics and Astronomy, University of Sussex, BN1 9QH, Brighton (United Kingdom); Riva, Francesco [CERN, Theory Division, 1211, Geneva (Switzerland); Sanz, Verónica [Department of Physics and Astronomy, University of Sussex, BN1 9QH, Brighton (United Kingdom)
2015-12-10
We introduce Rosetta, a program allowing for the translation between different bases of effective field theory operators. We present the main functions of the program and provide an example of usage. One of the Lagrangians which Rosetta can translate into has been implemented into FeynRules, which allows Rosetta to be interfaced into various high-energy physics programs such as Monte Carlo event generators. In addition to popular bases choices, such as the Warsaw and Strongly Interacting Light Higgs bases already implemented in the program, we also detail how to add new operator bases into the Rosetta package. In this way, phenomenological studies using an effective field theory framework can be straightforwardly performed.
Rosetta: an operator basis translator for standard model effective field theory
Energy Technology Data Exchange (ETDEWEB)
Falkowski, Adam [Universite Paris-Sud, Laboratoire de Physique Theorique, Bat. 210, Orsay (France); Fuks, Benjamin [Universite de Strasbourg/CNRS-IN2P3, Departement Recherches Subatomiques, Institut Pluridisciplinaire Hubert Curien, Strasbourg (France); Mawatari, Kentarou [Theoretische Natuurkunde and IIHE/ELEM, Vrije Universiteit Brussel, and International Solvay Institutes, Brussels (Belgium); Mimasu, Ken; Sanz, Veronica [University of Sussex, Department of Physics and Astronomy, Brighton (United Kingdom); Riva, Francesco [CERN, Theory Division, Geneva (Switzerland)
2015-12-15
We introduce Rosetta, a program allowing for the translation between different bases of effective field theory operators. We present the main functions of the program and provide an example of usage. One of the Lagrangians which Rosetta can translate into has been implemented into FeynRules, which allows Rosetta to be interfaced into various high-energy physics programs such as Monte Carlo event generators. In addition to popular bases choices, such as the Warsaw and Strongly Interacting Light Higgs bases already implemented in the program, we also detail how to add new operator bases into the Rosetta package. In this way, phenomenological studies using an effective field theory framework can be straightforwardly performed. (orig.)
International Nuclear Information System (INIS)
Ishimoto, Yukitaka
2004-01-01
Amongst conformal field theories, there exist logarithmic conformal field theories such as c p,1 models. We have investigated c p,q models with a boundary in search of logarithmic theories and have found logarithmic solutions of two-point functions in the context of the Coulomb gas picture. We have also found the relations between coefficients in the two-point functions and correlation functions of logarithmic boundary operators, and have confirmed the solutions in [hep-th/0003184]. Other two-point functions and boundary operators have also been studied in the free boson construction of boundary CFT with SU(2) k symmetry in regard to logarithmic theories. This paper is based on a part of D. Phil. Thesis [hep-th/0312160]. (author)
Techniques for Field Operation of Straddle-packer System in Deep Borehole
International Nuclear Information System (INIS)
Kim, Kyung Su; Park, Kyung Woo; Kim, Geon Young; Ji, Sung Hoon; Koh, Yong Kwon; Choi, Jong Won
2010-05-01
It is necessary to establish an appropriate hydro-testing tool for the qualified characterization of deep geological environments, especially for the hydraulic properties of rock formation. This research project had been initiated for the purpose of establishment of advanced infra-structures in KURT. The straddle packer system was developed for hydraulic characterization of geological formation using deep borehole. This technical report consists of design concept, basic requirements, function of each part, field operation procedures and techniques, detail design drawings, and specifications. The qualified hydro-testing tool, which is suitable for medium to low permeable formation, using large and deep borehole, has been developed. This tool will be applied for the research project on development of HLW disposal technologies and the site characterization activities of LILW disposal project. Prior to field operation using this hydro-testing equipment, every researchers should be well acquainted with this technical report
On the algebra of deformed differential operators, and induced integrable Toda field theory
International Nuclear Information System (INIS)
Hssaini, M.; Kessabi, M.; Maroufi, B.; Sedra, M.B.
2000-07-01
We build in this paper the algebra of q-deformed pseudo-differential operators shown to be an essential step towards setting a q-deformed integrability program. In fact, using the results of this q-deformed algebra, we derive the q-analogues of the generalised KdV hierarchy. We focus in particular the first leading orders of this q-deformed hierarchy namely the q-KdV and q-Boussinesq integrable systems. We also present the q-generalisation of the conformal transformations of the currents u n , n ≥ 2 and discuss the primary condition of the fields w n , n ≥ 2 by using the Volterra gauge group transformations for the q-covariant Lax operators. An induced su(n)-Toda(su(2)-Liouville) field theory construction is discussed and other important features are presented. (author)
International Nuclear Information System (INIS)
Uzun, Yunus; Kurt, Erol
2013-01-01
Highlights: • This paper explores the piezoelectric harvester performance. • The varying magnetic field generates electricity via exciting harvester. • Generated power should be optimized via load resistance. • 0.11 mW/cm 3 Power can be generated from 500 cm 3 surrounding volume. - Abstract: This paper reports a performance exploration of a piezoelectric harvester which is positioned near an operating induction motor. The harvester includes a magnet knob in a pendulum arrangement, which ascertains mechanical vibrations under the varying magnetic field. This energy harvester transforms the ambient unused magnetic energy into the electricity due to the piezoelectric layer attached to the pendulum. It has been proven that when the motor is under operation, the varying ambient field causes a varying magnetic force at the tip of harvester, then output voltage between the terminals of piezoelectric layer is produced due to the mechanical vibrations. This output signal has some characteristics of the operating induction motor in terms of its operation frequency, number of magnetic pole and natural frequency of the harvester. Since the surrounding field of the induction motor directly depends on the current flowing through the windings and electrical parameters, both the amplitude U and the frequency ω m of the harvested voltage can be characterized after some certain parametrical explorations. It has been proven that the harvested voltage strictly depends on the electrical load, which is attached to the terminals of the harvester, after the rectifying circuit. The harvested power per surrounding volume can be increased up to 0.11 mW/cm 3 , if the entire surrounding volume of the motor is considered
Summary of field operations Magazine Road North Wells MRN-1 and MRN-2
International Nuclear Information System (INIS)
Fritts, J.E.; McCord, J.P.
1996-03-01
This report provides a summary of the field operations associated with the installation of the MRN-1 and MRN-2 test/monitoring wells. These wells were installed in December 1994 and January 1995 as part of the Site-Wide Hydrogeologic Characterization (SWHC) task field program. The SWHC task is part of the Sandia National Laboratories, New Mexico, Environmental Restoration Project carried out by the Environmental Operations Center, 7500. MRN-1 and MRN-2 are paired wells located near the western edge of Kirtland Air Force Base (KAFB), west of Technical Area 3 (TA3), and north of Magazine Road. (Note: MRN stands for Magazine Road North). During the MRN field operations, important subsurface geologic, hydrologic, chemical, and radiological data were obtained. Subsurface geologic data include descriptions of drill cuttings, core, and geophysical logs of the upper unit of the Santa Fe Group. The geology identified here can help determine the eastern limit of the ancestral Rio Grande lithofacies. Subsurface hydrologic data include borehole geophysical logs, and qualitative information obtained during well completion and development. In addition, future aquifer testing at the MRN site will generate data for the interpretation of aquifer parameters such as transmissivity. Samples were taken from core every 100 feet at MRN-1 for chemical and radiological analysis to provide background data for the Environmental Restoration Project
Note on the two inequivalent spin 1/2 baryon field operators
International Nuclear Information System (INIS)
Christos, G.A.
1985-01-01
There are two inequivalent spin 1/2 local baryon field operators that can be constructed from 3 quarks. A priori the Jsup(P)=1/2 + baryons can couple to any linear combination of these operators. We show however that the coupling of the 1/2 + baryons to these operators is determined by the value of the SU(3) ratio of F to D type peudoscalar-baryon couplings. The experimental value of this ratio implies, for example, that the proton couples strongly to (usup(T)Cγ 5 d)u and weakly to (usup(T)Cd)γ 5 u. This is of interest in QCD sum rule applications. (orig.)
A Test Platform for Planned Field Operations Using LEGO Mindstorms NXT
Directory of Open Access Journals (Sweden)
Gareth Edwards
2013-11-01
Full Text Available Testing agricultural operations and management practices associated with different machinery, systems and planning approaches can be both costly and time-consuming. Computer simulations of such systems are used for development and testing; however, to gain the experience of real-world performance, an intermediate step between simulation and full-scale testing should be included. In this paper, a potential common framework using the LEGO Mindstorms NXT micro-tractor platform is described in terms of its hardware and software components. The performance of the platform is demonstrated and tested in terms of its capability of supporting decision making on infield operation planning. The proposed system represents the basic measures for developing a complete test platform for field operations, where route plans, mission plans, multiple-machinery cooperation strategies and machinery coordination can be executed and tested in the laboratory.
Regional co-operation in the nuclear field: The Nordic experience
International Nuclear Information System (INIS)
Marcus, F.R.
1983-01-01
Experience from 25 years of co-operation in the nuclear field between the Nordic countries is described. A pragmatic approach with a minimum of formalism is used. The co-operation takes place mainly through ''horizontal'' channels between corresponding bodies in the different countries - safety authorities, research institutions, electricity producers, etc. In addition, a ''vertical'' co-ordination between these different circles is accomplished through a Nordic Liaison Committee. The experience shows that valuable results can be obtained, mainly through rationalization and improved use of resources. Difficulties, which are inherent in international co-operation, can be reduced, provided that there is a strong political will, an efficient system to promote contacts, and a flexible financing scheme. Apart from the benefits obtained in each of the countries - whether or not it has its own nuclear power - particular advantages accrue when a ''Nordic group'' can present co-ordinated viewpoints on the international scene. (author)
Field theory reformulated without self-energy parts: the dressing operator
International Nuclear Information System (INIS)
Haan, M. de
2004-01-01
The reformulation of field theory for avoiding self-energy parts in the dynamical evolution has been applied successfully in the framework of the Lee model [Ann. Phys. 311 (2004) 314], enabling a kinetic extension of the description. The basic ingredient is the recognition of these self-energy parts [Trends Stat. Phys. 3 (2000) 115]. The original reversible description is embedded in the new one and appears now as a restricted class of initial conditions [Progr. Theor. Phys. 109 (2003) 881]. This program is realized here in the reduced formalism for a scalar field, interacting with a two-level atom, beyond the usual rotating wave approximation. The kinetic evolution operator, previously surmised [Physica A 171 (1991) 159], is here derived from first principles, justifying the usual practice in optics where the common use of the so-called pole approximation [Atoms in Electromagnetic Fields, 1994, 119] should no longer be viewed as an approximation but as an alternative description in the appropriate formalism. That model illustrates how some dressing of the atomic levels (and vertices), through an appropriate operator, finds its place naturally into the new formalism since the bare and dressed ground states do no longer coincide. Moreover, finite velocity for field propagation is now possible in all cases, without the presence of precursors for multiple detections
Effect of paraffin saturation in a crude oil on operation of a field
Energy Technology Data Exchange (ETDEWEB)
Trebin, G F; Kapyrin, Yu V
1968-11-01
Both theoretical and practical studies in recent years have shown that in planning operational procedures for an oil field, the paraffin saturation of the crude oil must be considered. If the crude oil is essentially saturated with paraffin at reservoir condition, then paraffin deposition can occur around the well and in the well. Temperature in the reservoir can be lowered by 2 mechanisms: (1) by injection of water below reservoir temperature, and (2) by expansion of produced gas and consequent cooling of the produced oil. Possible application of these principles to several Soviet oil fields is discussed. In the Uzen field, a preliminary investigation is under way to test the feasibility of heating the injection water to prevent paraffin deposition in the reservoir.
Quiescent H-mode operation using torque from non-axisymmetric, non-resonant magnetic fields
International Nuclear Information System (INIS)
Burrell, K.H.; Garofalo, A.M.; Osborne, T.H.; Snyder, P.B.; Solomon, W.M.; Park, J.-K.; Fenstermacher, M.E.; Orlov, D.M.
2013-01-01
Quiescent H-mode (QH-mode) sustained by magnetic torque from non-axisymmetric magnetic fields is a promising operating mode for future burning plasmas including ITER. Using magnetic torque from n = 3 fields to replace counter-I p torque from neutral beam injection, we have achieved long duration, counter-rotating QH-mode operation with neutral beam injection (NBI) torque ranging continuously from counter-I p up to co-I p values of about 1 N m. This co-I p torque is about 3 times the scaled torque that ITER will have. This range also includes operation at zero net NBI torque, applicable to rf wave heated plasmas. These n = 3 fields have been created using coils either inside or, most recently, outside the toroidal coils. Experiments utilized an ITER-relevant lower single-null plasma shape and were done with ITER-relevant values ν ped * ∼0.08, β T ped ∼ 1%$ and β N = 2. Discharges have confinement quality H 98y2 = 1.3, exceeding the value required for ITER. Initial work with low q 95 = 3.4 QH-mode plasmas transiently reached fusion gain values of G = β N H 89 /q 95 2 =0.4, which is the desired value for ITER; the limits on G have not yet been established. This paper also includes the most recent results on QH-mode plasmas run without n = 3 fields and with co-I p NBI; these shots exhibit co-I p plasma rotation and require NBI torque ⩾2 N m. The QH-mode work to date has made significant contact with theory. The importance of edge rotational shear is consistent with peeling–ballooning mode theory. We have seen qualitative and quantitative agreement with the predicted torque from neoclassical toroidal viscosity. (paper)
Araneda, Bernardo
2018-04-01
We present weighted covariant derivatives and wave operators for perturbations of certain algebraically special Einstein spacetimes in arbitrary dimensions, under which the Teukolsky and related equations become weighted wave equations. We show that the higher dimensional generalization of the principal null directions are weighted conformal Killing vectors with respect to the modified covariant derivative. We also introduce a modified Laplace–de Rham-like operator acting on tensor-valued differential forms, and show that the wave-like equations are, at the linear level, appropriate projections off shell of this operator acting on the curvature tensor; the projection tensors being made out of weighted conformal Killing–Yano tensors. We give off shell operator identities that map the Einstein and Maxwell equations into weighted scalar equations, and using adjoint operators we construct solutions of the original field equations in a compact form from solutions of the wave-like equations. We study the extreme and zero boost weight cases; extreme boost corresponding to perturbations of Kundt spacetimes (which includes near horizon geometries of extreme black holes), and zero boost to static black holes in arbitrary dimensions. In 4D our results apply to Einstein spacetimes of Petrov type D and make use of weighted Killing spinors.
International co-operation in the nuclear field - past, present and prospects
International Nuclear Information System (INIS)
Goldschmidt, B.
1978-01-01
On the occasion of the 20th anniversary of its creation, the Nuclear Energy Agency of the Organization for Economic Co-operation and Development (NEA/OECD) held a symposium in Paris on 1 and 2 February 1978. Some 200 participants from the 23 Member countries of the NEA as well as representatives of the Commission of European Communities, FORATOM and the IAEA attended the symposium. At a panel discussion at the symposium, led by Dr. Sigvard Eklund, Director General of the IAEA, the future of international co-operation between advanced nations in the nuclear field was discussed. While recognizing that nuclear energy is at present going through a period of uncertainty pending resolution of the intertwined problems of gaining public confidence and of non-proliferation, the panel expressed its strong confidence in the future of nuclear power, and the vital contribution it would make, particularly between now and the end of the century. During the meeting, a critical review was made of the way in which international co-operation has evolved since the early stages of peaceful nuclear development, and of the influence on this co-operation of the changing relationship between government and industry. The contribution of international co-operation - and its limitations - was carefully scrutinized, notably in the crucial area of the nuclear fuel cycle
Radial electric field evolution in various operational modes in the TUMAN-3M tokamak
International Nuclear Information System (INIS)
Askinazi, L G; Kornev, V A; Krikunov, S V; Lebedev, S V; Smirnov, A I; Tukachinsky, A S; Vildjunas, M I; Zhubr, N A; Krupnik, L I; Tendler, M
2008-01-01
Radial electric field evolution has been studied on the TUAMN-3M tokamak in different modes of operation: ohmic and NBI heating, L- and H-modes, with and without strong MHD activity. Peripheral radial electric field was measured using Langmuire probes, which were inserted up to 2cm inside LCFS, while core plasma potential evolution was measured using HIBP diagnostic. It was found, that in presence of strong MHD activity radial electric field in a vicinity of the island changed sign from negative to positive and could reach up to 4kV/m. Central plasma potential exhibited a positive perturbation of ∼700V during the MHD burst. This positive radial electric field might lead to H-mode termination, both in ohmic and NBI heating cases. Possible mechanism of the positive E r generation, namely the electron losses along ergodized magnetic field lines in the presence of MHD-island, is discussed. The same mechanism might be responsible for the positive potential spikes during a saw-tooth crash, also observed using HIBP. Another phenomenon observed using HIBP was quasi-coherent potential oscillations with the frequency close to one of the GAM. Possible location of these oscillations in the core region r/a ∼ 0.33 is discussed
Effects of 60 Hz electric fields on operant and social stress behaviors of nonhuman primates
Energy Technology Data Exchange (ETDEWEB)
Rogers, W.R.; Coelho, A.M. Jr.; Easley, S.P.; Lucas, J.H.; Moore, G.T.; Orr, J.L.; Smith, H.D.; Taylor, L.L.; Tuttle, M.L.
1987-10-24
The objective of this program is to investigate, using the baboon as a nonhuman primate surrogate for the human, possible behavioral effects associated with exposure to high intensity 60 Hz electric fields. Results from this program, along with information from experiments conducted elsewhere, will be used by the Department of Energy (DOE) to estimate and evaluate the likelihood of deleterious consequences resulting from exposure of humans to the electric fields associated with power transmission over high voltage lines. This research program consists of four major research projects, all of which have been successfully completed. The first project evaluated the potentially aversive character of exposure to 60 Hz electric fields by determining the threshold intensity that produces escape or avoidance responses. The second project estimated the threshold intensity for detection threshold was 12 kV/m; the range of means was 6 to 16 kV/m. The third project assessed, in separate experiments conducted at 30 and 60 kV/m, effects of chronic exposure to electric fields on the performance of two operant conditioning tasks, fixed ratio (FR), and differential reinforcement of low rate (DRL). In the same two experiments, the fourth project investigated, using the systematic quantitative observational sampling methods of primatology, the possible stress-inducing effects of chronic exposure to 60 Hz electric fields on the behavior of baboons living in small social groups. 131 refs., 87 figs., 123 tabs.
Limited field investigation report for the 100-HR-3 operable unit
International Nuclear Information System (INIS)
1994-09-01
This limited field investigation (LFI) was conducted to assess the applicability of interim remedial measures (IRM) for reducing human health and environmental risks within the 100-HR-3 Groundwater Operable Unit. The 100-HR-3 Operable Unit is comprised of three subareas; the 100 D Area, the 100 H Area and those portions of the 600 Area between the two reactor areas. The operable unit is one of seven operable units associated with the 100 D and H Areas. Operable units 100-DR-1, 100-DR-2, 100-DR-3, 100-HR-1, 100-HR-2 and 100-IU-4 address contaminant sources while 100-HR-3 addresses contamination present in the underlying groundwater. The primary method of field investigation used during this LFI was the installation and sampling of monitoring wells. Samples were collected from the groundwater and soils, and submitted for laboratory analysis. Boreholes were surveyed for radiological contamination using downhole geophysical techniques to further delineate the locations and levels of contaminants. All samples were screened to ascertain the presence of volatile organic compounds and radionuclides. Analytical data were subjected to validation; all round one, two and three and a minimum of 10% of round four data associated with the LFI were validated. A screening method was used to identify contaminants of potential concern (COPC). This screening method eliminated from further consideration, constituents that were below background. Constituents which are considered non-toxic to humans were eliminated from the human health evaluation. Data consistency and blank contamination were also evaluated in the screening process. These COPC were then evaluated further in the qualitative risk assessment (QRA). A human health QRA was performed using conservative (maximum equilibrated contaminant levels from the LFI) analyses
Occupational radiation exposure history of Idaho Field Office Operations at the INEL
International Nuclear Information System (INIS)
Horan, J.R.; Braun, J.B.
1993-10-01
An extensive review has been made of the occupational radiation exposure records of workers at the Idaho National Engineering Laboratory (INEL) over the period of 1951 through 1990. The focus has been on workers employed by contractors and employees of the Idaho Field Operations Office (ID) of the United States Department of Energy (USDOE) and does not include the Naval Reactors Facility (NRF), the Argonne National Laboratory (ANL), or other operations field offices at the INEL. The radiation protection guides have decreased from 15 rem/year to 5 rem/year in 1990 for whole body penetrating radiation exposure. During these 40 years of nuclear operations (in excess of 200,000 man-years of work), a total of twelve individuals involved in four accidents exceeded the annual guidelines for exposure; nine of these exposures were received during life saving efforts on January 3, 1961 following the SL-1 reactor accident which killed three military personnel. These exposures ranged from 8 to 27 rem. Only one individual has exceeded the annual whole body penetrating radiation protection guidelines in the last 29 years
Portable, remotely operated, computer-controlled, quadrupole mass spectrometer for field use
International Nuclear Information System (INIS)
Friesen, R.D.; Newton, J.C.; Smith, C.F.
1982-04-01
A portable, remote-controlled mass spectrometer was required at the Nevada Test Site to analyze prompt post-event gas from the nuclear cavity in support of the underground testing program. A Balzers QMG-511 quadrupole was chosen for its ability to be interfaced to a DEC LSI-11 computer and to withstand the ground movement caused by this field environment. The inlet system valves, the pumps, the pressure and temperature transducers, and the quadrupole mass spectrometer are controlled by a read-only-memory-based DEC LSI-11/2 with a high-speed microwave link to the control point which is typically 30 miles away. The computer at the control point is a DEC LSI-11/23 running the RSX-11 operating system. The instrument was automated as much as possible because the system is run by inexperienced operators at times. The mass spectrometer has been used on an initial field event with excellent performance. The gas analysis system is described, including automation by a novel computer control method which reduces operator errors and allows dynamic access to the system parameters
Occupational radiation exposure history of Idaho Field Office Operations at the INEL
Energy Technology Data Exchange (ETDEWEB)
Horan, J.R.; Braun, J.B.
1993-10-01
An extensive review has been made of the occupational radiation exposure records of workers at the Idaho National Engineering Laboratory (INEL) over the period of 1951 through 1990. The focus has been on workers employed by contractors and employees of the Idaho Field Operations Office (ID) of the United States Department of Energy (USDOE) and does not include the Naval Reactors Facility (NRF), the Argonne National Laboratory (ANL), or other operations field offices at the INEL. The radiation protection guides have decreased from 15 rem/year to 5 rem/year in 1990 for whole body penetrating radiation exposure. During these 40 years of nuclear operations (in excess of 200,000 man-years of work), a total of twelve individuals involved in four accidents exceeded the annual guidelines for exposure; nine of these exposures were received during life saving efforts on January 3, 1961 following the SL-1 reactor accident which killed three military personnel. These exposures ranged from 8 to 27 rem. Only one individual has exceeded the annual whole body penetrating radiation protection guidelines in the last 29 years.
The da Vinci telerobotic surgical system: the virtual operative field and telepresence surgery.
Ballantyne, Garth H; Moll, Fred
2003-12-01
The United States Department of Defense developed the telepresence surgery concept to meet battlefield demands. The da Vinci telerobotic surgery system evolved from these efforts. In this article, the authors describe the components of the da Vinci system and explain how the surgeon sits at a computer console, views a three-dimensional virtual operative field, and performs the operation by controlling robotic arms that hold the stereoscopic video telescope and surgical instruments that simulate hand motions with seven degrees of freedom. The three-dimensional imaging and handlike motions of the system facilitate advanced minimally invasive thoracic, cardiac, and abdominal procedures. da Vinci has recently released a second generation of telerobots with four arms and will continue to meet the evolving challenges of surgery.
Costs and indices for domestic oil and gas field equipment and production operations, 1992--1995
International Nuclear Information System (INIS)
1996-08-01
This report presents estimated costs and cost indices for domestic oil and natural gas field equipment and production operations for 1992, 1993, 1994, and 1995. The costs of all equipment and services are those in effect during June of each year. The sum (aggregates) of the costs for representative leases by region, depth, and production rate were averaged and indexed. This provides a general measure of the increased or decreased costs from year to year for lease equipment and operations. These general measured do not capture changes in industry-wide costs exactly because of annual variations in the ratio of the total number of oil wells to the total number of gas wells. The detail provided in this report is unavailable elsewhere. The body of this report contains summary tables, and the appendices contain detailed tables
Price, Layne C.
2015-11-01
We consider a phenomenological model of inflation where the inflaton is the phase of a complex scalar field Φ . Planck-suppressed operators of O (f5/Mpl) modify the geometry of the vev ⟨Φ ⟩ at first order in the decay constant f , which adds a first-order periodic term to the definition of the canonically normalized inflaton ϕ . This correction to the inflaton induces a fixed number of extra oscillatory terms in the potential V ˜θp. We derive the same result in a toy scenario where the vacuum ⟨Φ ⟩ is an ellipse with an arbitrarily large eccentricity. These extra oscillations change the form of the power spectrum as a function of scale k and provide a possible mechanism for differentiating effective field theory motivated inflation from models where the angular shift symmetry is a gauge symmetry.
Anthropogenic seismicity rates and operational parameters at the Salton Sea Geothermal Field.
Brodsky, Emily E; Lajoie, Lia J
2013-08-02
Geothermal power is a growing energy source; however, efforts to increase production are tempered by concern over induced earthquakes. Although increased seismicity commonly accompanies geothermal production, induced earthquake rate cannot currently be forecast on the basis of fluid injection volumes or any other operational parameters. We show that at the Salton Sea Geothermal Field, the total volume of fluid extracted or injected tracks the long-term evolution of seismicity. After correcting for the aftershock rate, the net fluid volume (extracted-injected) provides the best correlation with seismicity in recent years. We model the background earthquake rate with a linear combination of injection and net production rates that allows us to track the secular development of the field as the number of earthquakes per fluid volume injected decreases over time.
Limited field investigation report for the 100-KR-4 Operable Unit
International Nuclear Information System (INIS)
1994-07-01
This limited field investigation (LFI) was conducted to optimize the use of interim remedial measures (IRM) for expediting clean up while maintaining a technically sound and cost-effective program. The 100-KR-4 Operable Unit is one of four operable units associated with the 100 K Area. Operable units KR-1, KR-2 and KR-3 address contaminant sources while 100-KR-4 addresses contamination present in the underlying groundwater. The IRM decision process for groundwater operable units is based on three aspects: (1) Is the concentration greater than Hanford background? (2) Does the concentration present a medium or high human-health risk? (3) Does the concentration exceed an ecologically based applicable, relevant and appropriate requirements (ARAR) or present an environmental hazard quotient > I? The primary methods of investigation used during this LFI were the installation of monitoring wells and sampling of groundwater. The samples collected from the groundwater and soils were submitted for laboratory analysis. Boreholes were surveyed for radiological contamination using downhole geophysical techniques to further delineate the location and degree of contamination. All soil samples were screened to ascertain the presence of volatile organic compounds and radionuclides. Analytical data were subjected to validation; all first round and a minimum of 10% of subsequent round data were validated
Limited field investigation report for the 100-DR-1 Operable Unit
International Nuclear Information System (INIS)
1994-06-01
This limited field investigation (LFI) report summarizes the data collection and analysis activities conducted during the 100-DR-1 Source Operable Unite LFI and the associated qualitative risk assessment (QRA), and makes recommendations on the continued candidacy of high-priority sites for interim remedial measures (IRM). The results and recommendations presented in this report are generally independent of future land use scenarios. The 100-DR-1 Operable Unit is one of four operable units associated with the 100 D/DR Area at the Hanford Site. The 100-DR-1 Operable Unit encompasses approximately 1.5 km 2 (0.59 mi 2 ) and is located immediately adjacent to the Columbia River shoreline. In general, it contains waste facilities associated with the original plant facilities constructed to support D Reactor facilities, as well as cooling water retention basin systems for both D and DR Reactors. The 100-DR-1 LFI began the investigative phase of the remedial investigation for a select number of high-priority sites. The LFI was performed to provide additional data needed to support selection, design and implementation of IRM, if needed. The LFI included data compilation, nonintrusive investigations, intrusive investigations, summarization of 100 Area aggregate studies, and data evaluation
Operator support systems in nuclear power plants. RDIPE's activities in the field of CSS
International Nuclear Information System (INIS)
Gorelov, A.
1996-01-01
Research and Development Institute of Power Engineering (RDIPE) works in the field of computerized support system for the RBMK NPP during last 15 years. The first system which had some special features to be classified as CSS was designed for the Ignalina NPP in the beginning of the 1980s. THese efforts were mainly aimed to create standards for CSS design and V and V; to establish general requirements for human-machine interface tools; to upgrade support of operator as well as maintenance and administrative staff by implementing new hardware and software into existing RBMK computer-based monitoring systems and to develop the SPDS for all RBMK units. (author)
Thermodynamic analysis of an upstream petroleum plant operated on a mature field
DEFF Research Database (Denmark)
Nguyen, Tuong-Van; Jacyno, Tomasz; Breuhaus, Peter
2014-01-01
Oil and gas processing on offshore platforms operates under changing boundary conditions over a field lifespan, as the hydrocarbon production declines and the water extraction increases. In this paper, the processing plant of the Draugen platform is evaluated by performing an energy and exergy...... and reconciliated process data. The total energy demand is moderately sensitive to daily and monthly variations: it ranges between 22 and 30 MW, of which 18-26 MW and about 3-4 MW are in electrical and thermal energy forms. The greatest exergy destruction takes place in the gas treatment (51%), recompression (12...
International Nuclear Information System (INIS)
Elias, V.; Steele, T.G.
1987-01-01
Several field theoretic aspects of the operator product expansion (OPE) augmentation of QCD have been examined. Gauge independence of quark self-energies at the mass shell corresponding to the mass m (characterizing the OPE expansion parameter m/p) has been verified to all orders of the OPE for dimension 3 and 5 chiral symmetry breaking condensates. Similarly, the necessary transversality of the quark condensate contribution to the gluon self-energy has been verified, provided that propagator masses appearing in the self-energy are equilibrated with the OPE mass parameter m
Representation of a gauge field via intrinsic “BRST” operator
Energy Technology Data Exchange (ETDEWEB)
Batalin, Igor A., E-mail: batalin@lpi.ru [P.N. Lebedev Physical Institute, Leninsky Prospect 53, 119 991 Moscow (Russian Federation); Tomsk State Pedagogical University, Kievskaya St. 60, 634061 Tomsk (Russian Federation); Lavrov, Peter M., E-mail: lavrov@tspu.edu.ru [Tomsk State Pedagogical University, Kievskaya St. 60, 634061 Tomsk (Russian Federation); National Research Tomsk State University, Lenin Ave. 36, 634050 Tomsk (Russian Federation)
2015-11-12
We show that there exists a representation of a matrix-valued gauge field via intrinsic “BRST” operator assigned to matrix-valued generators of a gauge algebra. In this way, we reproduce the standard formulation of the ordinary Yang–Mills theory. In the case of a generating quasigroup/groupoid, we give a natural counterpart to the Yang–Mills action. The latter counterpart does also apply as to the most general case of an involution for matrix-valued gauge generators.
Operation of SOI P-Channel Field Effect Transistors, CHT-PMOS30, under Extreme Temperatures
Patterson, Richard; Hammoud, Ahmad
2009-01-01
Electronic systems are required to operate under extreme temperatures in NASA planetary exploration and deep space missions. Electronics on-board spacecraft must also tolerate thermal cycling between extreme temperatures. Thermal management means are usually included in today s spacecraft systems to provide adequate temperature for proper operation of the electronics. These measures, which may include heating elements, heat pipes, radiators, etc., however add to the complexity in the design of the system, increases its cost and weight, and affects its performance and reliability. Electronic parts and circuits capable of withstanding and operating under extreme temperatures would reflect in improvement in system s efficiency, reducing cost, and improving overall reliability. Semiconductor chips based on silicon-on-insulator (SOI) technology are designed mainly for high temperature applications and find extensive use in terrestrial well-logging fields. Their inherent design offers advantages over silicon devices in terms of reduced leakage currents, less power consumption, faster switching speeds, and good radiation tolerance. Little is known, however, about their performance at cryogenic temperatures and under wide thermal swings. Experimental investigation on the operation of SOI, N-channel field effect transistors under wide temperature range was reported earlier [1]. This work examines the performance of P-channel devices of these SOI transistors. The electronic part investigated in this work comprised of a Cissoid s CHT-PMOS30, high temperature P-channel MOSFET (metal-oxide semiconductor field-effect transistor) device [2]. This high voltage, medium-power transistor is designed for geothermal well logging applications, aerospace and avionics, and automotive industry, and is specified for operation in the temperature range of -55 C to +225 C. Table I shows some specifications of this transistor [2]. The CHT-PMOS30 device was characterized at various temperatures
Energy Technology Data Exchange (ETDEWEB)
Lee, Seung Min; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Lee, Hyun Chul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)
2014-05-15
In this work, as an application of digital devices to NPPs, a cooperation support system to aid communication between MCR operators and field workers in Nuclear Power Plants (NPPs), NUclear COoperation Support and MObile document System (Nu-COSMOS), is suggested. It is not easy for MCR operators to estimate whether field workers conduct their work correctly because MCR operators cannot monitor field workers at a real time, and records on paper procedure written by field workers do not contain the detailed information about work process and results. Thus, for safety operation without any events induced by misunderstand and miscommunication between MCR operators and field workers, the Nu-COSMOS is developed and it will be useful from the supporting cooperation point of view. To support the cooperation between MCR operators and field workers in NPPs, the cooperation support and mobile documentation system Nu-COSMOS is suggested in this work. To improve usability and applicability of the suggested system, the results of using existed digital device based support systems were analyzed. Through the analysis, the disincentive elements of using digital device-based developments and the recommendations for developing new mobile based system were derived. Based on derived recommendations, two sub systems, the mobile device based in-formation storing system and the large screen based information sharing system were suggested. The usability of the suggested system will be conducted by a survey with questionnaires. Field workers and operators, and nuclear-related person who had experiences as an operator, graduate students affiliated in nuclear engineering department will use and test the functions of the suggested system. It is expected that the mobile based information storing system can reduce the field workers' work load and enhance the understanding of MCR operators about field operators work process by monitoring all work results and work processes stored in devices.
International Nuclear Information System (INIS)
Lee, Seung Min; Seong, Poong Hyun; Lee, Hyun Chul
2014-01-01
In this work, as an application of digital devices to NPPs, a cooperation support system to aid communication between MCR operators and field workers in Nuclear Power Plants (NPPs), NUclear COoperation Support and MObile document System (Nu-COSMOS), is suggested. It is not easy for MCR operators to estimate whether field workers conduct their work correctly because MCR operators cannot monitor field workers at a real time, and records on paper procedure written by field workers do not contain the detailed information about work process and results. Thus, for safety operation without any events induced by misunderstand and miscommunication between MCR operators and field workers, the Nu-COSMOS is developed and it will be useful from the supporting cooperation point of view. To support the cooperation between MCR operators and field workers in NPPs, the cooperation support and mobile documentation system Nu-COSMOS is suggested in this work. To improve usability and applicability of the suggested system, the results of using existed digital device based support systems were analyzed. Through the analysis, the disincentive elements of using digital device-based developments and the recommendations for developing new mobile based system were derived. Based on derived recommendations, two sub systems, the mobile device based in-formation storing system and the large screen based information sharing system were suggested. The usability of the suggested system will be conducted by a survey with questionnaires. Field workers and operators, and nuclear-related person who had experiences as an operator, graduate students affiliated in nuclear engineering department will use and test the functions of the suggested system. It is expected that the mobile based information storing system can reduce the field workers' work load and enhance the understanding of MCR operators about field operators work process by monitoring all work results and work processes stored in devices
Higgs-Yukawa model with higher dimension operators via extended mean field theory
Akerlund, Oscar
2016-01-01
Using Extended Mean Field Theory (EMFT) on the lattice, we study properties of the Higgs-Yukawa model as an approximation of the Standard Model Higgs sector, and the effect of higher dimension operators. We note that the discussion of vacuum stability is completely modified in the presence of a $\\phi^6$ term, and that the Higgs mass no longer appears fine tuned. We also study the finite temperature transition. Without higher dimension operators the transition is found to be second order (crossover with gauge fields) for the experimental value of the Higgs mass $M_h=125$ GeV. By taking a $\\phi^6$ interaction in the Higgs potential as a proxy for a UV completion of the Standard Model, the transition becomes stronger and turns first order if the scale of new physics, i.e. the mass of the lightest mediator particle, is around $1.5$ TeV. This implies that electroweak baryogenesis may be viable in models which introduce new particles around that scale.
Polley, John W; Figueroa, Alvaro A
2013-05-01
To introduce the concept and use of an occlusal-based "orthognathic positioning system" (OPS) to be used during orthognathic surgery. The OPS consists of intraoperative occlusal-based devices that transfer virtual surgical planning to the operating field for repositioning of the osteotomized dentoskeletal segments. The system uses detachable guides connected to an occlusal splint. An initial drilling guide is used to establish stable references or landmarks. These are drilled on the bone that will not be repositioned adjacent to the osteotomy line. After mobilization of the skeletal segment, a final positioning guide, referenced to the drilled landmarks, is used to transfer the skeletal segment according to the virtual surgical planning. The OPS is digitally designed using 3-dimensional computer-aided design/computer-aided manufacturing technology and manufactured with stereolithographic techniques. Virtual surgical planning has improved the preoperative assessment and, in conjunction with the OPS, the execution of orthognathic surgery. The OPS has the possibility to eliminate the inaccuracies commonly associated with traditional orthognathic surgery planning and to simplify the execution by eliminating surgical steps such as intraoperative measuring, determining the condylar position, the use of bulky intermediate splints, and the use of intermaxillary wire fixation. The OPS attempts precise translation of the virtual plan to the operating field, bridging the gap between virtual and actual surgery. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
Point-particle effective field theory I: classical renormalization and the inverse-square potential
Energy Technology Data Exchange (ETDEWEB)
Burgess, C.P.; Hayman, Peter [Physics & Astronomy, McMaster University,Hamilton, ON, L8S 4M1 (Canada); Perimeter Institute for Theoretical Physics,Waterloo, Ontario N2L 2Y5 (Canada); Williams, M. [Instituut voor Theoretische Fysica, KU Leuven,Celestijnenlaan 200D, B-3001 Leuven (Belgium); Zalavári, László [Physics & Astronomy, McMaster University,Hamilton, ON, L8S 4M1 (Canada); Perimeter Institute for Theoretical Physics,Waterloo, Ontario N2L 2Y5 (Canada)
2017-04-19
Singular potentials (the inverse-square potential, for example) arise in many situations and their quantum treatment leads to well-known ambiguities in choosing boundary conditions for the wave-function at the position of the potential’s singularity. These ambiguities are usually resolved by developing a self-adjoint extension of the original problem; a non-unique procedure that leaves undetermined which extension should apply in specific physical systems. We take the guesswork out of this picture by using techniques of effective field theory to derive the required boundary conditions at the origin in terms of the effective point-particle action describing the physics of the source. In this picture ambiguities in boundary conditions boil down to the allowed choices for the source action, but casting them in terms of an action provides a physical criterion for their determination. The resulting extension is self-adjoint if the source action is real (and involves no new degrees of freedom), and not otherwise (as can also happen for reasonable systems). We show how this effective-field picture provides a simple framework for understanding well-known renormalization effects that arise in these systems, including how renormalization-group techniques can resum non-perturbative interactions that often arise, particularly for non-relativistic applications. In particular we argue why the low-energy effective theory tends to produce a universal RG flow of this type and describe how this can lead to the phenomenon of reaction catalysis, in which physical quantities (like scattering cross sections) can sometimes be surprisingly large compared to the underlying scales of the source in question. We comment in passing on the possible relevance of these observations to the phenomenon of the catalysis of baryon-number violation by scattering from magnetic monopoles.
Thermodynamic analysis of an upstream petroleum plant operated on a mature field
Energy Technology Data Exchange (ETDEWEB)
Nguyen, Tuong-Van [Section of Thermal Energy, Department of Mechanical Engineering, Technical University of Denmark, Building 403, Nils Koppels Allé, 2800 Kongens Lyngby (Denmark); Jacyno, Tomasz [Faculty of Mechanical and Power Engineering, Wrocław University of Technology, Building A-1, ul. Wybrzeże Wyspiańskiego 27, 50-370 Wrocław (Poland); Breuhaus, Peter [Department of Energy, International Research Institute of Stavanger, Professor Olav Hanssens vei 15, 4021 Stavanger (Norway); Voldsund, Mari [Department of Chemistry, Norwegian University of Science and Technology, Høgskoleringen 5, 7491 Trondheim (Norway); Elmegaard, Brian [Section of Thermal Energy, Department of Mechanical Engineering, Technical University of Denmark, Building 403, Nils Koppels Allé, 2800 Kongens Lyngby (Denmark)
2014-04-01
Oil and gas processing on offshore platforms operates under changing boundary conditions over a field lifespan, as the hydrocarbon production declines and the water extraction increases. In this paper, the processing plant of the Draugen platform is evaluated by performing an energy and exergy analysis. This facility exploits an end-life oilfield and runs at conditions deviating significantly from its optimal operating specifications. Two different operating modes were assessed, and process models were developed using the simulation tools Aspen Plus{sup ®} and Aspen HYSYS{sup ®}, based on measured and reconciliated process data. The total energy demand is moderately sensitive to daily and monthly variations: it ranges between 22 and 30 MW, of which 18–26 MW and about 3–4 MW are in electrical and thermal energy forms. The greatest exergy destruction takes place in the gas treatment (51%), recompression (12%) and production manifold (10%) modules. The separation work performed on this platform is greater than in similar facilities because of higher propane and water fractions of the well-streams. These findings emphasise the differences between peak and end-life productions: they suggest (i) to set focus on processes including gas expansion and compression, (ii) to investigate possibilities for an improved energy integration, and (iii) to consider and evaluate alternative system designs. - Highlights: • The thermodynamic performance of an upstream oil and gas processing plant is assessed. • Energy and exergy analyses are performed, and the plant inefficiencies are depicted. • The effects of end-life field conditions are evaluated.
Thermodynamic analysis of an upstream petroleum plant operated on a mature field
International Nuclear Information System (INIS)
Nguyen, Tuong-Van; Jacyno, Tomasz; Breuhaus, Peter; Voldsund, Mari; Elmegaard, Brian
2014-01-01
Oil and gas processing on offshore platforms operates under changing boundary conditions over a field lifespan, as the hydrocarbon production declines and the water extraction increases. In this paper, the processing plant of the Draugen platform is evaluated by performing an energy and exergy analysis. This facility exploits an end-life oilfield and runs at conditions deviating significantly from its optimal operating specifications. Two different operating modes were assessed, and process models were developed using the simulation tools Aspen Plus ® and Aspen HYSYS ® , based on measured and reconciliated process data. The total energy demand is moderately sensitive to daily and monthly variations: it ranges between 22 and 30 MW, of which 18–26 MW and about 3–4 MW are in electrical and thermal energy forms. The greatest exergy destruction takes place in the gas treatment (51%), recompression (12%) and production manifold (10%) modules. The separation work performed on this platform is greater than in similar facilities because of higher propane and water fractions of the well-streams. These findings emphasise the differences between peak and end-life productions: they suggest (i) to set focus on processes including gas expansion and compression, (ii) to investigate possibilities for an improved energy integration, and (iii) to consider and evaluate alternative system designs. - Highlights: • The thermodynamic performance of an upstream oil and gas processing plant is assessed. • Energy and exergy analyses are performed, and the plant inefficiencies are depicted. • The effects of end-life field conditions are evaluated
Modeling the wind-fields of accidental releases with an operational regional forecast model
International Nuclear Information System (INIS)
Albritton, J.R.; Lee, R.L.; Sugiyama, G.
1995-01-01
The Atmospheric Release Advisory Capability (ARAC) is an operational emergency preparedness and response organization supported primarily by the Departments of Energy and Defense. ARAC can provide real-time assessments of atmospheric releases of radioactive materials at any location in the world. ARAC uses robust three-dimensional atmospheric transport and dispersion models, extensive geophysical and dose-factor databases, meteorological data-acquisition systems, and an experienced staff. Although it was originally conceived and developed as an emergency response and assessment service for nuclear accidents, the ARAC system has been adapted to also simulate non-radiological hazardous releases. For example, in 1991 ARAC responded to three major events: the oil fires in Kuwait, the eruption of Mt. Pinatubo in the Philippines, and the herbicide spill into the upper Sacramento River in California. ARAC's operational simulation system, includes two three-dimensional finite-difference models: a diagnostic wind-field scheme, and a Lagrangian particle-in-cell transport and dispersion scheme. The meteorological component of ARAC's real-time response system employs models using real-time data from all available stations near the accident site to generate a wind-field for input to the transport and dispersion model. Here we report on simulation studies of past and potential release sites to show that even in the absence of local meteorological observational data, readily available gridded analysis and forecast data and a prognostic model, the Navy Operational Regional Atmospheric Prediction System, applied at an appropriate grid resolution can successfully simulate complex local flows
Burhan, Muhammad
2016-11-25
Current commercial CPV systems are designed as large units which are targeted to be installed in open desert fields with high DNI availability. It appeared that the CPV is among some of those technologies which gained very little attention of people, with less customers and market. For conventional PV systems, the installations at the rooftop of commercial and residential buildings have a significant share in the total installed capacity of PV systems. That is why for most of the countries, the PV installations at the rooftop of commercial and residential buildings are aimed to be increased to half of total installed PV. On the other hand, there is no commercial CPV system available to be suitable for rooftop operation, giving motivation for the development of CPV field of compact systems. This paper discusses the development of a CPV field for the rooftop operation, comprising of compact CPV system with cost effective but highly accurate solar tracking sensor and wireless master slave control. In addition, the performance of the developed CPV systems is evaluated for production of hydrogen, which can be used as energy carrier or energy storage and a maximum solar to hydrogen efficiency of 18% is obtained. However, due to dynamic nature of the weather data and throughout the day variations in the performance of CPV and electrolyser, the solar to hydrogen performance is proposed to be reported as daily and long term average efficiency. The CPV-Hydrogen system showed daily average conversion efficiency of 15%, with solar to hydrogen production rate of 218 kW h/kg.
International Nuclear Information System (INIS)
1994-01-01
This report presents estimated costs and indice for domestic oil and gas field equipment and production operations for 1990, 1991, 1992, and 1993. The costs of all equipment and serives were those in effect during June of each year. The sums (aggregates) of the costs for representative leases by region, depth, and production rate were averaged and indexed. This provides a general measure of the increased or decreased costs from year to year for lease equipment and operations. These general measures do not capture changes in industry-wide costs exactly because of annual variations in the ratio of oil wells to gas wells. The body of the report contains summary tables, and the appendices contain detailed tables. Price changes for oil and gas, changes in taxes on oil and gas revenues, and environmental factors (costs and lease availability) have significant impact on the number and cost of oil and gas wells drilled. These changes also impact the cost of oil and gas production equipment and operations
Energy Technology Data Exchange (ETDEWEB)
1994-07-08
This report presents estimated costs and indice for domestic oil and gas field equipment and production operations for 1990, 1991, 1992, and 1993. The costs of all equipment and serives were those in effect during June of each year. The sums (aggregates) of the costs for representative leases by region, depth, and production rate were averaged and indexed. This provides a general measure of the increased or decreased costs from year to year for lease equipment and operations. These general measures do not capture changes in industry-wide costs exactly because of annual variations in the ratio of oil wells to gas wells. The body of the report contains summary tables, and the appendices contain detailed tables. Price changes for oil and gas, changes in taxes on oil and gas revenues, and environmental factors (costs and lease availability) have significant impact on the number and cost of oil and gas wells drilled. These changes also impact the cost of oil and gas production equipment and operations.
International Nuclear Information System (INIS)
1998-03-01
This report presents estimated costs and cost indices for domestic oil and natural gas field equipment and production operations for 1994, 1995, 1996, and 1997. The costs of all equipment and services are those in effect during June of each year. The sums (aggregates) of the costs for representative leases by region, depth, and production rate were averaged and indexed. This provides a general measure of the increased or decreased costs from year to year for lease equipment and operations. These general measures do not capture changes in industry-wide costs exactly because of annual variations in the ratio of the total number of oil wells to the total number of gas wells. The detail provided in this report is unavailable elsewhere. The body of this report contains summary tables, and the appendices contain detailed tables. Price changes for oil and gas, changes in taxes on oil and gas revenues, and environmental factors (compliance costs and lease availability) have a significant impact on the number and cost of oil and gas wells drilled. These changes also impact the cost of oil and gas equipment and production operations
Lim, Mikyung; Song, Jaeman; Kim, Jihoon; Lee, Seung S.; Lee, Ikjin; Lee, Bong Jae
2018-05-01
The present work successfully achieves a strong enhancement in performance of a near-field thermophotovoltaic (TPV) system operating at low temperature and large-vacuum-gap width by introducing a hyperbolic-metamaterial (HMM) emitter, multilayered graphene, and an Au-backside reflector. Design variables for the HMM emitter and the multilayered-graphene-covered TPV cell are optimized for maximizing the power output of the near-field TPV system with the genetic algorithm. The near-field TPV system with the optimized configuration results in 24.2 times of enhancement in power output compared with that of the system with a bulk emitter and a bare TPV cell. Through the analysis of the radiative heat transfer together with surface-plasmon-polariton (SPP) dispersion curves, it is found that coupling of SPPs generated from both the HMM emitter and the multilayered-graphene-covered TPV cell plays a key role in a substantial increase in the heat transfer even at a 200-nm vacuum gap. Further, the backside reflector at the bottom of the TPV cell significantly increases not only the conversion efficiency, but also the power output by generating additional polariton modes which can be readily coupled with the existing SPPs of the HMM emitter and the multilayered-graphene-covered TPV cell.
Noise levels of a track-laying tractor during field operations in the vineyard
Directory of Open Access Journals (Sweden)
Pietro Catania
2013-09-01
Full Text Available Noise in agriculture is one of the risk factors to be taken into account in the assessment of the health and safety of workers; in particular, it is known that the tractor is a source of high noise. The Italian Low Decree 81/2008 defined the requirements for assessing and managing noise risk identifying a number of procedures to be adopted at different noise levels to limit workers exposure. This paper concerns the analysis of the noise risk arising from the use of a tracklaying tractor during field operations carried out in the vineyard. The objective of this study was to evaluate the noise level that comes close to the ear of the operator driving the tractor measuring the values of equivalent sound level (Leq(A and peak sound pressure (LCpk. We considered four options related to the same tractor coupled with the following tools to perform some farming operations: rototilling, chisel plough, flail mowers and vibro farmer. We considered three test conditions: T1 in flat (slope 0%, T2 uphill and T3 downhill (both 30% slope. The instrument used for the measurements is a precision integrating portable sound level meter, class 1, model HD2110L by Delta OHM, Italy. Each survey lasted 2 minutes, with an interval of measurement equal to 0.5 s. The tests were performed in compliance with the standards ISO 9612 and ISO 9432. The results show that the measured sound levels exceed the limits allowed by the regulations in almost all the test conditions; values exceeding the threshold limit of 80 dB(A were recorded coming up to a maximum value of 92.8 dB(A for flail mowers in test T1. When limits imposed by the regulations are exceeded, the operator is obliged to wear the appropriate Personal Protective Equipment.
Group of local biholomorphisms of C/sup 1/ and conformal field theory on the operator formalism
Energy Technology Data Exchange (ETDEWEB)
Budzynski, R.J.; Klimek, S.; Sadowski, P.
1989-01-01
Motivated by the operator formulation of conformal field theory on Riemann surfaces, we study the properties of the infinite dimensional group of local biholomorphic transformations (conformal reparametrizations) of C/sup 1/ and develop elements of its representation theory.
2003-10-01
The purpose of this document is to expand upon the evaluation components presented in "Computer-aided dispatch--traffic management center field operational test final evaluation plan : WSDOT deployment". This document defines the objective, approach,...
2004-01-01
The purpose of this document is to expand upon the evaluation components presented in "Computer-aided dispatch--traffic management center field operational test final evaluation plan : state of Utah". This document defines the objective, approach, an...
First and second order operator splitting methods for the phase field crystal equation
International Nuclear Information System (INIS)
Lee, Hyun Geun; Shin, Jaemin; Lee, June-Yub
2015-01-01
In this paper, we present operator splitting methods for solving the phase field crystal equation which is a model for the microstructural evolution of two-phase systems on atomic length and diffusive time scales. A core idea of the methods is to decompose the original equation into linear and nonlinear subequations, in which the linear subequation has a closed-form solution in the Fourier space. We apply a nonlinear Newton-type iterative method to solve the nonlinear subequation at the implicit time level and thus a considerably large time step can be used. By combining these subequations, we achieve the first- and second-order accuracy in time. We present numerical experiments to show the accuracy and efficiency of the proposed methods
Directory of Open Access Journals (Sweden)
Takumi Takeuchi
2012-01-01
Full Text Available Transurethral resection of the prostate is the gold standard of surgical treatment for benign prostatic hyperplasia (BPH. Nevertheless, open subcapsular prostatectomy is still performed for large BPH. While enucleation of prostatic adenoma is being performed, unneglectable bleeding can occur and surgeons need to rush to remove adenomas, often using fingers and in a blinded fashion. The blood supply to the prostatic capsule and adenoma can be reduced to a marked extent in subcapsular prostatectomy if the bilateral internal iliac arteries are transiently occluded. Thus, a bloodless operative field is reasonably acquired during enucleation of adenoma, which would, otherwise, be a cause for concern to surgeons due to bleeding. It is not always applicable, but it could be an option if the estimated volume of BPH is more than 100 mL. In two cases, bilateral internal iliac arteries were occluded with Bulldog clamps, and then adenomas of 159 and 97 g were enucleated.
This SOP describes the method for conducting internal field audits and quality control procedures. Internal field audits will be conducted to ensure the collection of high quality data. Internal field audits will be conducted by Field Auditors (the Field QA Officer and the Field...
Scientific co-operation with IAEA in the field of marine radioactivity
International Nuclear Information System (INIS)
Bologa, S.Alexandru
1998-01-01
A short presentation of the communication presented in the Seminar on public information on peaceful uses of nuclear energy, NUCInfo'98, is given. It is emphasized the formation of RMRI specialists, its scientific co-operations with IAEA between 1986-1998 and participations in related scientific events. In the domain of specialists' formation there are mentioned the participation of members of the Institute in the training courses on marine radioecology, in the regional course on strategies and methodologies for applied marine radioactivity and environmental isotope studies for the Black Sea, and in the inter-regional course devoted to determination of radionuclides in environmental samples, held in 1986, 1994 and 1997, respectively. In the field of research co-operation there are presented the achievements obtained in the framework of five programs dealing mainly with monitoring of marine water, sediment and biota radioactivity in Romanian sector of Black Sea. Also reported are the participations and the contributions in the international scientific events devoted to marine environmental studies and the contributions to international databases
Design techniques for a stable operation of cryogenic field-programmable gate arrays
Homulle, Harald; Visser, Stefan; Patra, Bishnu; Charbon, Edoardo
2018-01-01
In this paper, we show how a deep-submicron field-programmable gate array (FPGA) can be operated more stably at extremely low temperatures through special firmware design techniques. Stability at low temperatures is limited through long power supply wires and reduced performance of various printed circuit board components commonly employed at room temperature. Extensive characterization of these components shows that the majority of decoupling capacitor types and voltage regulators are not well behaved at cryogenic temperatures, asking for an ad hoc solution to stabilize the FPGA supply voltage, especially for sensitive applications. Therefore, we have designed a firmware that enforces a constant power consumption, so as to stabilize the supply voltage in the interior of the FPGA. The FPGA is powered with a supply at several meters distance, causing significant resistive voltage drop and thus fluctuations on the local supply voltage. To achieve the stabilization, the variation in digital logic speed, which directly corresponds to changes in supply voltage, is constantly measured and corrected for through a tunable oscillator farm, implemented on the FPGA. The impact of the stabilization technique is demonstrated together with a reconfigurable analog-to-digital converter (ADC), completely implemented in the FPGA fabric and operating at 15 K. The ADC performance can be improved by at most 1.5 bits (effective number of bits) thanks to the more stable supply voltage. The method is versatile and robust, enabling seamless porting to other FPGA families and configurations.
Development and simulation of soft morphological operators for a field programmable gate array
Tickle, Andrew J.; Harvey, Paul K.; Smith, Jeremy S.; Wu, Q. Henry
2013-04-01
In image processing applications, soft mathematical morphology (MM) can be employed for both binary and grayscale systems and is derived from set theory. Soft MM techniques have improved behavior over standard morphological operations in noisy environments, as they can preserve small details within an image. This makes them suitable for use in image processing applications on portable field programmable gate arrays for tasks such as robotics and security. We explain how the systems were developed using Altera's DSP Builder in order to provide optimized code for the many different devices currently on the market. Also included is how the circuits can be inserted and combined with previously developed work in order to increase their functionality. The testing procedures involved loading different images into these systems and analyzing the outputs against MATLAB-generated validation images. A set of soft morphological operations are described, which can then be applied to various tasks and easily modified in size via altering the line buffer settings inside the system to accommodate a range of image attributes ranging from image sizes such as 320×240 pixels for basic webcam imagery up to high quality 4000×4000 pixel images for military applications.
Direct-written polymer field-effect transistors operating at 20 MHz.
Perinot, Andrea; Kshirsagar, Prakash; Malvindi, Maria Ada; Pompa, Pier Paolo; Fiammengo, Roberto; Caironi, Mario
2016-12-12
Printed polymer electronics has held for long the promise of revolutionizing technology by delivering distributed, flexible, lightweight and cost-effective applications for wearables, healthcare, diagnostic, automation and portable devices. While impressive progresses have been registered in terms of organic semiconductors mobility, field-effect transistors (FETs), the basic building block of any circuit, are still showing limited speed of operation, thus limiting their real applicability. So far, attempts with organic FETs to achieve the tens of MHz regime, a threshold for many applications comprising the driving of high resolution displays, have relied on the adoption of sophisticated lithographic techniques and/or complex architectures, undermining the whole concept. In this work we demonstrate polymer FETs which can operate up to 20 MHz and are fabricated by means only of scalable printing techniques and direct-writing methods with a completely mask-less procedure. This is achieved by combining a fs-laser process for the sintering of high resolution metal electrodes, thus easily achieving micron-scale channels with reduced parasitism down to 0.19 pF mm -1 , and a large area coating technique of a high mobility polymer semiconductor, according to a simple and scalable process flow.
Development of Nb nanoSQUIDs based on SNS junctions for operation in high magnetic fields
Energy Technology Data Exchange (ETDEWEB)
Morosh, Viacheslav; Kieler, Oliver; Weimann, Thomas; Zorin, Alexander [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany); Mueller, Benedikt; Martinez-Perez, Maria Jose; Kleiner, Reinhold; Koelle, Dieter [Physikalisches Institut and Center for Quantum Science in LISA+, Universitaet Tuebingen (Germany)
2016-07-01
Investigation of the magnetization reversal of single magnetic nanoparticles requires SQUIDs with high spatial resolution, high spin sensitivity (a few Bohr magneton μ{sub B}) and at the same time sufficient stability in high magnetic fields. We fabricated dc nanoSQUIDs comprising overdamped SNS sandwich-type (Nb/HfTi/Nb) Josephson junctions using optimized technology based on combination of electron beam lithography and chemical-mechanical polishing. Our nanoSQUIDs have Josephson junctions with lateral dimensions ≤ 150 nm x 150 nm, effective loop areas < 0.05 μm{sup 2} and the distance between the Josephson junctions ≤ 100 nm. The feeding strip lines of the width ≤ 200 nm have been realized. The nanoSQUIDs have shown stable operation in external magnetic fields at least up to 250 mT. Sufficiently low level of flux noise resulting in spin sensitivity of few tens μ{sub B}/Hz{sup 1/2} has been demonstrated. A further reduction of the nanoSQUID size using our technology is possible.
Towards “Operating Within” the Field: Doctoral Students’ Views of Supervisors’ Discipline Expertise
Directory of Open Access Journals (Sweden)
Jan Gube
2017-01-01
Full Text Available Aim/Purpose: This paper considers the role of supervisors’ discipline expertise in doctoral learning from a student perspective. Background:\tDoctoral students need to develop expertise in a particular field of study. In this context, developing expertise requires doctoral students to master disciplinary knowledge, conventions and scholarship under the guidance of supervisors. Methodology\t: The study draws on a mixed-method approach, using an online survey and semi-structured interviews conducted with doctoral students. Contribution: The paper brings to the fore the role of supervisors’ discipline expertise on doctoral students’ research progress. Findings: The survey data suggest that doctoral students nominate their supervisors on the basis of their discipline expertise. They also view supervisors’ expertise as key to the development of ‘insider’ knowledge of their doctoral research. Recommendations for Practitioners: Supervisors play a pivotal role in helping doctoral students overcome intellectual barriers by imparting their discipline knowledge as well as balancing satisfactory doctoral completion rate and high quality student experience. Impact on Society\t: Doctoral supervision equips doctoral students with the right arsenal to be able to competently operate within their field and prepares them for their future research or professional career that demands a high level of discipline expertise. Future Research:\tThe scope of the findings leaves open a discussion about the experiences of doctoral students matched with non-discipline expert supervisory teams; for example, the extent of the mismatch and its ramifications.
Limited field investigation report for the 100-NR-1 Operable Unit
International Nuclear Information System (INIS)
1995-03-01
This limited field investigation (LFI) report summarizes the data collection and analysis activities conducted during the 100-NR-1 Source Operable Unit LFI and the associated qualitative risk assessment (QRA), and makes recommendations on the continued candidacy of high-priority sites for interim remedial measures (IRM). The results and recommendations presented in this report are generally independent of future land-use scenarios. This report is unique in that it is based on Hanford-specific agreements discussed in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) (Ecology et al. 1992), the Hanford Site Risk Assessment Methodology (DOE-RL 1994a), the Remedial Investigation Feasibility Study Work Plan for the 100-NR-1 Operable Unit (DOE-RL 1992a), and the Hanford Past-Practice Strategy (HPPS) (DOE-RL 1991), and must be viewed in this context. The HPPS emphasizes initiating and completing waste site cleanup through interim actions. The strategy includes paths for interim decision-making and a final remedy-selection process for the operable unit. A LFI report is required, in accordance with the HPPS, when waste sites are to be considered for IRM and existing data are insufficient to formulate a conceptual model or perform a QRA. The purpose of the report is to identify those sites that are recommended to remain as candidates for IRM, provide a preliminary summary of site characterization studies, refine the conceptual model as needed, identify potential contaminant- and location-specific applicable or relevant and appropriate requirements (ARAR), and provide a qualitative assessment of the risks associated with the sites. This assessment includes consideration of whether contaminant concentrations pose a risk to human health or the environment that warrants action through IRM
Naor, Michael; Heyman, Samuel N; Bader, Tarif; Merin, Ofer
2017-01-01
The Israeli Defense Force (IDF) Medical Corps developed a model of airborne field hospital. This model was structured to deal with disaster settings, requiring self-sufficiency, innovation and flexible operative mode in the setup of large margins of uncertainty regarding the disaster environment. The current study is aimed to critically analyze the experience, gathered in ten such missions worldwide. Interviews with physicians who actively participated in the missions from 1988 until 2015 as chief medical officers combined with literature review of principal medical and auxiliary publications in order to assess and integrate information about the assembly of these missions. A body of knowledge was accumulated over the years by the IDF Medical Corps from deploying numerous relief missions to both natural (earthquake, typhoon, and tsunami), and man-made disasters, occurring in nine countries (Armenia, Rwanda, Kosovo, Turkey, India, Haiti, Japan, Philippines, and Nepal). This study shows an evolutionary pattern with improvements implemented from one mission to the other, with special adaptations (creativity and improvisation) to accommodate logistics barriers. The principals and operative function for deploying medical relief system, proposed over 20 years ago, were challenged and validated in the subsequent missions of IDF outlined in the current study. These principals, with the advantage of the military infrastructure and the expertise of drafted civilian medical professionals enable the rapid assembly and allocation of highly competent medical facilities in disaster settings. This structure model is to large extent self-sufficient with a substantial operative flexibility that permits early deployment upon request while the disaster assessment and definition of needs are preliminary.
van Hulst, N.F.; Moers, M.H.P.; Moers, M.H.P.; Noordman, O.F.J.; Noordman, O.F.J.; Faulkner, T.; Segerink, Franciscus B.; van der Werf, Kees; de Grooth, B.G.; Bölger, B.; Bölger, B.
1992-01-01
Images obtained with a scanning near field optical microscope (SNOM) operating in reflection are presented. We have obtained the first results with a SiN tip as optical probe. The instrument is simultaneously operated as a scanning force microscope (SFM). Moreover, the instrument incorporates an
Pseudo-invariant Eigen-Operator Method for Solving Field-Intensity-Dependent Jaynes-Cummings Model
International Nuclear Information System (INIS)
Yu Taxi; Fan Hongyi
2010-01-01
By using the pseudo invariant eigen-operator method we analyze the field-intensity-dependent Jaynes-Gumming (JC) model. The pseudo-invariant eigen-operator is found in terms of the supersymmetric generators. The energy-level gap of this JC Hamiltonian is derived. This approach seems concise. (general)
Boekel, van M.A.J.S.; Meerdink, G.; Banati, D.; Marvin, H.J.P.; Kuiper, H.A.; Houtman, C.B.
2002-01-01
This paper explains the situation in Hungary and The Netherlands regarding scientific co-operation, networking and capacity building in the field of food quality and safety. Specific details are given about institutional co-operation including exchanges between staff and students, collaborative
Weisburd, Melvin I.
The Field Operations and Enforcement Manual for Air Pollution Control, Volume II, explains in detail the following: technology of source control, modification of operations, particulate control equipment, sulfur dioxide removal systems for power plants, and control equipment for gases and vapors; inspection procedures for general sources, fuel…
National Research Council Canada - National Science Library
Kirejczyk, Harry J
2006-01-01
...: the Unitized Group Ration-A (UGR-A) and the Unitized Group Ration-Heat/Serve (UGR-H/S). These fieldings were designed to increase the frequency and quality of group hot meals and reduce the cook workloads generated by field feeding operations...
Oceanic gamefish/Skylab project field operating plan for operations 4, 5 August. [in Gulf of Mexico
1973-01-01
The operation plans are presented for the oceanic Gamefish/Skylab Experiment 240, which was conducted to obtain fish catch data for the northeast area of the Gulf of Mexico. The plans for surface measurements, aerial observations, and communications are included.
Johnson, Caleb D; Simonson, Andrew J; Darnell, Matthew E; DeLany, James P; Wohleber, Meleesa F; Connaboy, Christopher
2018-04-01
The purpose of this study was to identify and compare energy requirements specific to Special Operations Forces in field training, in both cool and hot environments. Three separate training sessions were evaluated, 2 in a hot environment (n = 21) and 1 in a cool environment (n = 8). Total energy expenditure was calculated using doubly labeled water. Dietary intake was assessed via self-report at the end of each training mission day, and macronutrient intakes were calculated. Across the 3 missions, mean energy expenditure (4618 ± 1350 kcal/day) exceeded mean energy intake (2429 ± 838 kcal/day) by an average of 2200 kcal/day. Macronutrient intakes (carbohydrates (g/(kg·day body weight (bw)) -1 ) = 3.2 ± 1.2; protein (g/(kg·day bw) -1 ) = 1.3 ± 0.7; fat (g/(kg·day bw) -1 ) = 1.2 ± 0.7) showed inadequate carbohydrate and possibly protein intake across the study period, compared with common recommendations. Total energy expenditures were found to be similar between hot (4664 ± 1399 kcal/day) and cool (4549 ± 1221 kcal/day) environments. However, energy intake was found to be higher in the cool (3001 ± 900 kcal/day) compared with hot (2200 ± 711 kcal/day) environments. Based on the identified energy deficit, high variation in energy expenditures, and poor macronutrient intake, a greater attention to feeding practices during similar training scenarios for Special Operations Forces is needed to help maintain performance and health. The differences in environmental heat stress between the 2 climates/environments had no observed effect on energy expenditures, but may have influenced intakes.
Navlakha, Nupur; Kranti, Abhinav
2017-07-01
Insights into device physics and operation through the control of energy barriers are presented for a planar tri-gate Tunnel Field Effect Transistor (TFET) based dynamic memory. The architecture consists of a double gate (G1) at the source side and a single gate (G2) at the drain end of the silicon film. Dual gates (G1) effectively enhance the tunneling based read mechanism through the enhanced coupling and improved electrostatic control over the channel. The single gate (G2) controls the holes in the potential barrier induced through the proper selection of bias and workfunction. The results indicate that the planar tri-gate achieves optimum performance evaluated in terms of two composite metrics (M1 and M2), namely, product of (i) Sense Margin (SM) and Retention Time (RT) i.e., M1 = SM × RT and (ii) Sense Margin and Current Ratio (CR) i.e., M2 = SM × CR. The regulation of barriers created by the gates (G1 and G2) through the optimal use of device parameters leads to better performance metrics, with significant improvement at scaled lengths as compared to other tunneling based dynamic memory architectures. The investigation shows that lengths of G1, G2 and lateral spacing can be scaled down to 25 nm, 50 nm, and 30 nm, respectively, while achieving reasonable values for (M1, M2). The work demonstrates a systematic approach to showcase the advancement in TFET based Dynamic Random Access Memory (DRAM) through the use of planar tri-gate topology at a lower bias value. The concept, design, and operation of planar tri-gate architecture provide valuable viewpoints for TFET based DRAM.
Mignan, Arnaud
2018-03-01
The aftershock productivity law is an exponential function of the form K ∝ exp(αM), with K being the number of aftershocks triggered by a given mainshock of magnitude M and α ≈ ln(10) being the productivity parameter. This law remains empirical in nature although it has also been retrieved in static stress simulations. Here, we parameterize this law using the solid seismicity postulate (SSP), the basis of a geometrical theory of seismicity where seismicity patterns are described by mathematical expressions obtained from geometric operations on a permanent static stress field. We first test the SSP that relates seismicity density to a static stress step function. We show that it yields a power exponent q = 1.96 ± 0.01 for the power-law spatial linear density distribution of aftershocks, once uniform noise is added to the static stress field, in agreement with observations. We then recover the exponential function of the productivity law with a break in scaling obtained between small and large M, with α = 1.5ln(10) and ln(10), respectively, in agreement with results from previous static stress simulations. Possible biases of aftershock selection, proven to exist in epidemic-type aftershock sequence (ETAS) simulations, may explain the lack of break in scaling observed in seismicity catalogues. The existence of the theoretical kink, however, remains to be proven. Finally, we describe how to estimate the solid seismicity parameters (activation density δ+, aftershock solid envelope r∗ and background stress amplitude range Δo∗) for large M values.
Directory of Open Access Journals (Sweden)
Stefan Hollands
2009-09-01
Full Text Available In this paper, we propose a new framework for quantum field theory in terms of consistency conditions. The consistency conditions that we consider are ''associativity'' or ''factorization'' conditions on the operator product expansion (OPE of the theory, and are proposed to be the defining property of any quantum field theory. Our framework is presented in the Euclidean setting, and is applicable in principle to any quantum field theory, including non-conformal ones. In our framework, we obtain a characterization of perturbations of a given quantum field theory in terms of a certain cohomology ring of Hochschild-type. We illustrate our framework by the free field, but our constructions are general and apply also to interacting quantum field theories. For such theories, we propose a new scheme to construct the OPE which is based on the use of non-linear quantized field equations.
Energy Technology Data Exchange (ETDEWEB)
Zielinski, Lech [Universite du Littoral, LMPA (France)], E-mail: lech.zielinski@lmpa.univ-littoral.fr
2002-06-15
Let A=A{sub 0}+v(x) where A{sub 0} is a second-order uniformly elliptic self-adjoint operator in R{sup d} and v is a real valued polynomially growing potential. Assuming that v and the coefficients of A{sub 0} are Hoelder continuous, we study the asymptotic behaviour of the counting function N(A,{lambda}) ({lambda}{sup {yields}}{infinity}) with the remainder estimates depending on the regularity hypotheses. Our strongest regularity hypotheses involve Lipschitz continuity and give the remainder estimate N(A,{lambda})O({l_brace}{lambda}{r_brace}{sup -{mu}}), where {mu} may take an arbitrary value strictly smaller than the best possible value known in the smooth case. In particular, our results are obtained without any hypothesis on critical points of the potential.
Water Distribution System Operation and Maintenance. A Field Study Training Program. Second Edition.
Kerri, Kenneth D.; And Others
Proper installation, inspection, operation, maintenance, repair and management of water distribution systems have a significant impact on the operation and maintenance cost and effectiveness of the systems. The objective of this manual is to provide water distribution system operators with the knowledge and skills required to operate and maintain…
Limited field investigation report for the 100-NR-1 operable unit. Draft A
International Nuclear Information System (INIS)
1994-08-01
This limited field investigation (LFI) report summarizes the data collection and analysis activities conducted during the 100-NR-1 Source Operable Unit LFI and the associated qualitative risk assessment (QRA), and makes recommendations on the continued candidacy of high-priority sites for interim remedial measures (IRM). The results and recommendations presented in this report are generally independent of future land-use scenarios. An LFI report is required when waste sites are to be considered for IRM and existing data are insufficient to formulate a conceptual model or perform a QRA. The purpose of the report is to identify those sites that are recommended to remain as candidates for IRM, provide a preliminary summary of site characterization studies, refine the conceptual model as needed, identify potential contaminant and location-specific applicable or relevant and appropriate requirements (ARAR), and provide a qualitative assessment of the risks associated with the sites. This assessment includes consideration of whether contaminant concentrations pose a risk to human health or the environment that warrants action through IRM. Seven sites were intrusively investigated: 1322-N, 116-N-2, 119-N, 120-N-2, 120-N-1, South Settling Pond, and the 166-N Tank Farm (UN-100-N-17) unplanned release at the 166-N Tank Farm. Vadose zone sediments from these sites were sampled and analyzed. Radiological contamination is the primary concern as confirmed through this study
Limited field investigation report for the 100-FR-1 Operable Unit
International Nuclear Information System (INIS)
1995-09-01
This limited field investigation (LFI) report summarizes the data collection and analysis activities conducted during the 100-FR-1 Source Operable Unit LFI and the associated qualitative risk assessment (QRA), and makes recommendations on the continued candidacy of high-priority sites for interim remedial measures (IRM). The results and recommendations presented in this report are generally independent of future land use scenarios. An LFI is required when existing data are insufficient to formulate a conceptual model and perform a QRA. The purpose of the report is to identify those sites that are recommended to remain as candidates for IRM, provide a preliminary summary of site characterization studies, refine the conceptual model as needed, identify contaminant- and location-specific applicable or relevant and appropriate requirements (ARAR), and provide a qualitative assessment of the risks associated with the sites. This assessment includes consideration of whether contaminant concentrations pose an unacceptable risk that warrants action through IRM. The final decision to conduct an IRM will rely on many factors including risk, ARAR, future land use, point of compliance, time of compliance, a bias-for-action, and the threat to human health and the environment
International Nuclear Information System (INIS)
Kulikov, N.Ya.; Snitko, Eh.I.; Rasputnis, A.M.; Solodov, V.P.
1976-01-01
Describes the system of intrareactor control over the reactors of the Byeloyarskaya Atomic Station. In the second block of the station, use is made of direct charge emission detectors installed in the central apertures of the superheater channels and operating reliably at temperatures up to 750 deg C. The detectors of the first and the second block are connected to the computer which sends the results of processing the signals to the printer, while the signals for deviations go to the mnemonic tablaux of the reactors. The good working order of the detectors is checked by comparison with zero as well as with the mean detector current for the reactor concerned. The application of the intrareactor control system has allowed the stable thermal power to be increased from 480-500 to 530 Mw and makes it possible to control and maintain the neutron field formed with a relative error of 3-4%. The structural scheme of the system of intrareactor control is given
Bauer, David J; Kerr, Abigail L; Swain, Rodney A
2011-02-01
Recently identified pathways from the dentate nuclei of the cerebellum to the rostral cerebral cortex via the thalamus suggest a cerebellar role in frontal and prefrontal non-motor functioning. Disturbance of cerebellar morphology and connectivity, particularly involving these cerebellothalamocortical (CTC) projections, has been implicated in motivational and cognitive deficits. The current study explored the effects of CTC disruption on motivation in male Long Evans rats. The results of two experiments demonstrate that electrolytic lesions of the cerebellar dentate nuclei lower breaking points on an operant conditioning progressive ratio schedule and decrease open field exploration compared to sham controls. Changes occurred in the absence of motor impairment, assessed via lever pressing frequency and rotarod performance. Similar elevated plus maze performances between lesioned and sham animals indicated that anxiety did not influence task performance. Our results demonstrate hedonic and purposive motivational reduction and suggest a CTC role in global motivational processes. These implications are discussed in terms of psychiatric disorders such as schizophrenia and autism, in which cerebellar damage and motivational deficits often present concomitantly. Copyright © 2010 Elsevier Inc. All rights reserved.
Directory of Open Access Journals (Sweden)
F. Rezaee
2009-10-01
Full Text Available Background and aimsIntensity of Magnetic and Electric fields around visual displayterminals and its association on health effects were studied.Methodsmagnetic and electric fields intensities around 237 VDTs at distances 30¡50¡ 60 cm and different operating conditions (active¸ screen saver¸ shut down with use of HI-3603 device according to Svensk standard method were monitored. Resultsmagnetic and electric fields Intensities at 30 cm were higher than standard and at 50 cm Monitors in all measurements were lower than standard (20mA/m MPRII, TCO and (1V/m,TCO Magnetic fields intensities of LCD monitors in rare side were higher than all other directionsand rise versa intensities of magnetic fields of cathodiC monitors were in front than other sides. Differences of magnetic and electric fields intensities were not significant in various operating conditions (screen saver and active operation. Comparison of chronic syndrome of exhaustion in two groups of case and control, demonstrated higher of prevalence of symptoms such as shedding tears, eye irritation and fatigue in case rather than control group.Conclusionat time of procurement of monitors TCO standard label should be noticed. During recess times, monitors should be turned off in order to reduce exposure to electric and magnetic fields.
Energy Technology Data Exchange (ETDEWEB)
Saprykin, E. G. [Russian Academy of Sciences, Institute of Automation and Electrometry, Siberian Branch (Russian Federation); Chernenko, A. A., E-mail: chernen@isp.nsc.ru [Russian Academy of Sciences, Rzhanov Institute of Semiconductor Physics, Siberian Branch (Russian Federation); Shalagin, A. M. [Russian Academy of Sciences, Institute of Automation and Electrometry, Siberian Branch (Russian Federation)
2016-08-15
Analytical and numerical investigations are carried out of the effect of spontaneous decay through operating transition on the shape of a resonance in the work of a probe field under a strong field applied to the transition. A narrow nonlinear resonance arising on transitions with long-living lower level in the work of a probe field can manifest itself in the form of a traditional minimum and a peak as a function of the first Einstein coefficient for the operating transition. The transformation of the resonance from a minimum to a peak is attributed to the specific character of relaxation of lower-level population beatings on a closed or almost closed transition (the decay of the upper level occurs completely or almost completely through the operating transition).
Energy Technology Data Exchange (ETDEWEB)
Michael D. Durham
2004-10-01
PG&E NEG Salem Harbor Station Unit 1 was successfully tested for applicability of activated carbon injection as a mercury control technology. Test results from this site have enabled a thorough evaluation of mercury control at Salem Harbor Unit 1, including performance, estimated cost, and operation data. This unit has very high native mercury removal, thus it was important to understand the impacts of process variables on native mercury capture. The team responsible for executing this program included plant and PG&E headquarters personnel, EPRI and several of its member companies, DOE, ADA, Norit Americas, Inc., Hamon Research-Cottrell, Apogee Scientific, TRC Environmental Corporation, Reaction Engineering, as well as other laboratories. The technical support of all of these entities came together to make this program achieve its goals. Overall the objectives of this field test program were to determine the mercury control and balance-of-plant impacts resulting from activated carbon injection into a full-scale ESP on Salem Harbor Unit 1, a low sulfur bituminous-coal-fired 86 MW unit. It was also important to understand the impacts of process variables on native mercury removal (>85%). One half of the gas stream was used for these tests, or 43 MWe. Activated carbon, DARCO FGD supplied by NORIT Americas, was injected upstream of the cold side ESP, just downstream of the air preheater. This allowed for approximately 1.5 seconds residence time in the duct before entering the ESP. Conditions tested in this field evaluation included the impacts of the Selective Non-Catalytic Reduction (SNCR) system on mercury capture, of unburned carbon in the fly ash, of adjusting ESP inlet flue gas temperatures, and of boiler load on mercury control. The field evaluation conducted at Salem Harbor looked at several sorbent injection concentrations at several flue gas temperatures. It was noted that at the mid temperature range of 322-327 F, the LOI (unburned carbon) lost some of its
Tartakoff, David S.
1994-01-01
We prove global analytic hypoellipticity on a product of tori for partial differential operators which are constructed as rigid (variable coefficient) quadratic polynomials in real vector fields satisfying the H\\"ormander condition and where $P$ satisfies a `maximal' estimate. We also prove an analyticity result that is local in some variables and global in others for operators whose prototype is $$ P= \\left({\\partial \\over {\\partial x_1}}\\right)^2 + \\left({\\partial \\over {\\partial x_2}}\\righ...
Limited field investigation report for the 100-HR-1 Operable Unit
International Nuclear Information System (INIS)
1994-08-01
This limited field investigation (LFI) report summarizes the data collection and analysis activities conducted during the 100-HR-1 Source Operable Unit LFI and the associated qualitative risk assessment (QRA) (WHC 1993a), and makes recommendations on the continued candidacy of high-priority sites for interim remedial measures (IRM). The results and recommendations presented in this report are generally independent of future land use scenarios. A LFI Report is required, in accordance with the HPPS, when waste sites are to be considered for IRMs. The LFI is an integral part of the remedial investigation/feasibility study (RI/FS) or Resource Conservation and Recovery Act (RCRA) facility investigation/corrective measures study (RFI/CMS) and process and functions as a focused RI or RFI for selection of IRMs. The purpose of the report is to identify those sites that are recommended to remain as candidates for IRMs, provide a preliminary summary of site characterization studies, refine the conceptual model as needed, identify contaminant- and location-specific applicable or relevant and appropriate requirements (ARA), and provide a qualitative assessment of the risks associated with the sites. This assessment includes consideration of whether contaminant concentrations pose an unacceptable risk that warrants action through IRMs. The 100-HR-1 unit encompasses approximately 100 acres adjacent to the Columbia River shoreline. It contains waste units associated with the original plant facilities constructed to support the H Reactor. The area also contains evaporation basins which received liquid process wastes and nonroutine deposits of chemical wastes from the 300 Area, where fuel elements for the N Reactor were produced
Operational, Social, and Religious Influences upon the Army Chaplain Field Manual, 1926-1952
National Research Council Canada - National Science Library
Nay, Robert
2008-01-01
The early formulation of the Army Chaplain Field Manual reveals the Army Chaplaincy struggling with individuals using the Army Chaplain Field Manual to further their social and religious beliefs upon other chaplains...
Blank, H. Richard; Healy, J.H.; Roller, John; Lamson, Ralph; Fisher, Fred; McClearn, Robert; Allen, Steve
1979-01-01
In February 1978 a seismic deep-refraction profile was recorded by the USGS along a 1000-km line across the Arabian Shield in western Saudi Arabia. The line begins in Paleozoic and Mesozoic cover rocks near Riyadh on the Arabian Platform, leads southwesterly across three major Precambrian tectonic provinces, traverses Cenozoic rocks of the coastal plain near Jizan (Tihamat Asir), and terminates at the outer edge of the Farasan Bank in the southern Red Sea. More than 500 surveyed recording sites were occupied, including 19 in the Farasan Islands. Six shot points were used--five on land, with charges placed mostly below water table in drill holes, and one at sea, with charges placed on the sea floor and fired from a ship. The total charge consumed was slightly in excess of 61 metric tons in 21 discrete firings. Seismic energy was recorded by means of a set of 100 newly developed portable seismic stations. Each station consists of a standard 2-Hz vertical geophone coupled to a self-contained analog recording instrument equipped with a magnetic-tape cassette. The stations were deployed in groups of 20 by five observer teams, each generally consisting of two scientist-technicians and a surveyor-guide. On the day prior to deployment, the instruments were calibrated and programmed for automatic operation by means of a specially designed device called a hand-held tester. At each of ten pre-selected recording time windows on a designated firing day, the instruments were programmed to turn on, stabilize, record internal calibration signals, record the seismic signals at three levels of amplification, and then deactivate. After the final window in the firing sequence, all instruments were retrieved and their data tapes removed for processing. A specially designed, field tape- dubbing system was utilized at shot point camps to organize and edit data recorded on the cassette tapes. The main functions of this system are to concatenate all data from each shot on any given day
Field trials of 100G and beyond: an operator's point of view
Vorbeck, S.; Schneiders, M.; Weiershausen, W.; Mayer, H.; Schippel, A.; Wagner, P.; Ehrhardt, A.; Braun, R.; Breuer, D.; Drafz, U.; Fritzsche, D.
2011-01-01
In this article we present a summary of the latest 100 Gbps field trials in the network of Deutsche Telekom AG with industry partners. We cover a brown field approach as alien wavelength on existing systems, a green field high speed overlay network approach and a high speed interface router-router coupling.
Nuclear axial current operators to fourth order in chiral effective field theory
Energy Technology Data Exchange (ETDEWEB)
Krebs, H., E-mail: hermann.krebs@rub.de [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Epelbaum, E., E-mail: evgeny.epelbaum@rub.de [Institut für Theoretische Physik II, Ruhr-Universität Bochum, D-44780 Bochum (Germany); Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93016 (United States); Meißner, U.-G., E-mail: meissner@hiskp.uni-bonn.de [Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn (Germany); Institut für Kernphysik, Institute for Advanced Simulation, and Jülich Center for Hadron Physics, Forschungszentrum Jülich, D-52425 Jülich (Germany); JARA - High Performance Computing, Forschungszentrum Jülich, D-52425 Jülich (Germany)
2017-03-15
We present the complete derivation of the nuclear axial charge and current operators as well as the pseudoscalar operators to fourth order in the chiral expansion relative to the dominant one-body contribution using the method of unitary transformation. We demonstrate that the unitary ambiguity in the resulting operators can be eliminated by the requirement of renormalizability and by matching of the pion-pole contributions to the nuclear forces. We give expressions for the renormalized single-, two- and three-nucleon contributions to the charge and current operators and pseudoscalar operators including the relevant relativistic corrections. We also verify explicitly the validity of the continuity equation.
Energy Technology Data Exchange (ETDEWEB)
Retterdal, Atle; Hansen, Hans Birger [Statoil, Stavanger (Norway)
1999-07-01
Since production started on the satellite fields Statfjord Nord and East in 1995 and 1994, respectively, some opportunities for improvement have been discovered and realized both with respect to the subsea systems and the operational routines and philosophy. This presentation discusses the improvement projects. It is known from experience that creative ideas usually originate at the interfaces between supplier/customer, engineers with different backgrounds, or between different technologies. The interface between supplier and operator is very important for discovering creative solutions. The interface between Statoil and the suppliers of underwater equipment is not sufficiently well developed on the operational side.
Graff, Trevor G.; Morris, R. V.; Klingelhofer, G.; Blumers, M.
2013-01-01
Field testing and scientific investigations were conducted on the Mauna Kea Volcano, Hawaii, as part of the 2012 Moon and Mars Analog Mission Activities (MMAMA). Measurements were conducted using both stand-alone and rover-mounted instruments to determine the geophysical and geochemical properties of the field site, as well as provide operational constraints and science considerations for future robotic and human missions [1]. Reported here are the results from the two MIMOS instruments deployed as part of this planetary analog field test.
Broek, T.H.A. van den; Netten, B.D.; Hoedemaeker, M.; Ploeg, J.
2010-01-01
In this paper, a large field operational test (FOT) for cooperative driving systems, which take place on a public highway, is discussed. The experimental setup consist of a specific driver support system, which is closely related to cooperative adaptive cruise control (CACC) systems. Instead of
International Nuclear Information System (INIS)
Inahama, Yuzuru; Shirai, Shin-ichi
2003-01-01
We study the essential spectrum of the magnetic Schroedinger operators on the Poincare upper-half plane and establish a hyperbolic analog of Iwatsuka's result [J. Math. Kyoto Univ. 23(3), 475-480 (1983)] on the stability of the essential spectrum under perturbations from constant magnetic fields
Forejt, L.; Drkal, F.; Hensen, J.L.M.; Seppänen, O.; Säteri, J.
2007-01-01
Air distribution in mobile operating room was assessed according to the recent acceptance test (VDI, 2004 [1]). This standard presents a simple and uniform validation procedure of operating room air distribution systems. Therefore it was applied as an objective method for evaluating performance of
Operation of Wastewater Treatment Plants: A Field Study Training Program. Volume I. Second Edition.
California State Univ., Sacramento. Dept. of Civil Engineering.
This manual was prepared by experienced wastewater collection system workers to provide a home study course to develop new qualified workers and expand the abilities of existing workers. This volume is directed primarily towards entry-level operators and the operators of ponds, package plants, or small treatment plants. Ten chapters examine the…
Fostering sustainable operations in a natural resource management agency: insights from the field
Patricia L. Winter; Shawn M. Burn
2010-01-01
Sustainable operations (SO; operating in an environmentally, economically, and socially sustainable manner) is consistent with the environmental stewardship mission of natural resource management organizations. This study sought to examine SO practices in the daily work lives of US Forest Service employees, including those primarily stationed in the office and in the...
Sandhåland, Hilde; Oltedal, Helle A; Hystad, Sigurd W; Eid, Jarle
2015-06-01
This study provides empirical data about shipboard practices in bridge operations on board a selection of platform supply vessels (PSVs). Using the theoretical concept of distributed situation awareness, the study examines how situation awareness (SA)-related information is distributed and coordinated at the bridge. This study thus favours a systems approach to studying SA, viewing it not as a phenomenon that solely happens in each individual's mind but rather as something that happens between individuals and the tools that they use in a collaborative system. Thus, this study adds to our understanding of SA as a distributed phenomenon. Data were collected in four field studies that lasted between 8 and 14 days on PSVs that operate on the Norwegian continental shelf and UK continental shelf. The study revealed pronounced variations in shipboard practices regarding how the bridge team attended to operational planning, communication procedures, and distracting/interrupting factors during operations. These findings shed new light on how SA might decrease in bridge teams during platform supply operations. The findings from this study emphasize the need to assess and establish shipboard practices that support the bridge teams' SA needs in day-to-day operations. Provides insights into how shipboard practices that are relevant to planning, communication and the occurrence of distracting/interrupting factors are realized in bridge operations.Notes possible areas for improvement to enhance distributed SA in bridge operations.
Energy Technology Data Exchange (ETDEWEB)
Michael D. Durham
2005-03-17
Brayton Point Unit 1 was successfully tested for applicability of activated carbon injection as a mercury control technology. Test results from this site have enabled a thorough evaluation of the impacts of future mercury regulations to Brayton Point Unit 1, including performance, estimated cost, and operation data. This unit has variable (29-75%) native mercury removal, thus it was important to understand the impacts of process variables and activated carbon on mercury capture. The team responsible for executing this program included: (1) Plant and PG&E National Energy Group corporate personnel; (2) Electric Power Research Institute (EPRI); (3) United States Department of Energy National Energy Technology Laboratory (DOE/NETL); (4) ADA-ES, Inc.; (5) NORIT Americas, Inc.; (6) Apogee Scientific, Inc.; (7) TRC Environmental Corporation; (8) URS Corporation; (9) Quinapoxet Solutions; (10) Energy and Environmental Strategies (EES); and (11) Reaction Engineering International (REI). The technical support of all of these entities came together to make this program achieve its goals. Overall, the objectives of this field test program were to determine the impact of activated carbon injection on mercury control and balance-of-plant processes on Brayton Point Unit 1. Brayton Point Unit 1 is a 250-MW unit that fires a low-sulfur eastern bituminous coal. Particulate control is achieved by two electrostatic precipitators (ESPs) in series. The full-scale tests were conducted on one-half of the flue gas stream (nominally 125 MW). Mercury control sorbents were injected in between the two ESPs. The residence time from the injection grid to the second ESP was approximately 0.5 seconds. In preparation for the full-scale tests, 12 different sorbents were evaluated in a slipstream of flue gas via a packed-bed field test apparatus for mercury adsorption. Results from these tests were used to determine the five carbon-based sorbents that were tested at full-scale. Conditions of interest
International Nuclear Information System (INIS)
Schroeder, Markus; Brown, Alex
2009-01-01
We present a modified version of a previously published algorithm (Gollub et al 2008 Phys. Rev. Lett.101 073002) for obtaining an optimized laser field with more general restrictions on the search space of the optimal field. The modification leads to enforcement of the constraints on the optimal field while maintaining good convergence behaviour in most cases. We demonstrate the general applicability of the algorithm by imposing constraints on the temporal symmetry of the optimal fields. The temporal symmetry is used to reduce the number of transitions that have to be optimized for quantum gate operations that involve inversion (NOT gate) or partial inversion (Hadamard gate) of the qubits in a three-dimensional model of ammonia.
International Nuclear Information System (INIS)
Lee, Sungjin; Seong, Nokyu; Jung, Yeonsub
2013-01-01
This paper explains the technical issues of the mobile CPS (m-CPS) in the conceptual development stage. The proposed m-CPS can be developed with many recent technologies in the various industry fields based on CRI CPS. Performance and stability of CRI CPS have been tested several times until now. It is expected that more human errors can be reduced by the m-CPS through improved situation awareness and human performance tools for local workers and MCR operators. Some considerations as well as mentioned ones will be reflected in the m-CPS development. Human errors can occur during the test and maintenance of the generator, safety injection system and reactor coolant inventory in nuclear power plants (NPPs). Most of human errors have been occurred by the omission of the prevention techniques such as the self-check, the peer-check, the concurrent verification and etc. Another important reason is the insufficient information sharing among main control room (MCR) operators and field workers. Various field service automation tools have been developed with recent information technology in many countries. APR1400 computerized procedure system (CPS) has been developed for the MCR operators of Shin-Kori 3 and 4 units. Especially, the concurrent verification support design is applied in the construction project of Shin-Hanul 1 and 2 CPS. KHNP central research institute (CRI) expects that the extended application of CPS including the field activity, that is a kind of mobile CPS, can enhance the reduction of human errors
DEFF Research Database (Denmark)
Berning, Torsten; Kær, Søren Knudsen
2012-01-01
A multiphase fuel cell model based on computational fluid dynamics is used to investigate the possibility of operating a proton exchange membrane fuel cell at low stoichiometric flow ratios (ξ gases. A case study...
Draft Title V Operating Permit: Andeavor Field Services, LLC - Walker Hollow Compressor Station
Draft Operating Permit (Permit Number: V-UO-000979-2017.00), statement of basis, public notice bulletin, and the administrative permit docket (application and other supporting documents) for the Andeavor Walker Hollow Compressor Station.
Burhan, Muhammad; Oh, Seung Jin; Chua, Kian Jon Ernest; Ng, Kim Choon
2016-01-01
installations at the rooftop of commercial and residential buildings are aimed to be increased to half of total installed PV. On the other hand, there is no commercial CPV system available to be suitable for rooftop operation, giving motivation
Automated operation and management of the oil fields in Western Siberia
Energy Technology Data Exchange (ETDEWEB)
Guernault, P.; Valleur, M.
1979-11-01
In October 1978, Technip signed a contract worth 850 mf with the Soviet central purchasing organization, Mashinoimport, for the design and construction of 2 large complexes intended to improve the production of the Soviet Samotlor and Fyodorovsk fields. These fields are located in West Siberia near the towns of Nijnivartovsk and Surgut, in the OB Valley, approximately 600 km south of the Arctic Circle. They are among the largest in the Soviet Union. The present output of the Samotlor field exceeds 100 mt/yr; the 2 fields taken together comprise 2400 wells in the final stage, spread over an area of 2000 sq km. These installations thus are the largest to be designed to date with the gas lift method: i.e., the reinjection of high pressure gas into the production string. They make use of high performance compressor plants but their main feature is above all their very high level of automation.
Field Marshal Erich Von Manstein and the Operational Art at the Battle of Kharkov
National Research Council Canada - National Science Library
Thompson, Thomas
2000-01-01
Field Marshal Erich von Manstein was one of Hitler's most competent generals. He was a master of maneuver warfare who orchestrated the counterattacks of Germany's Army Group South during the Winter Campaign of 1942-43...
International Nuclear Information System (INIS)
Luong, M.
1997-09-01
The enhanced electronic field emission from large area metallic surfaces lowers performances of industrial devices that have to sustain high electric field under vacuum. Despite of numerous investigations in the past, the mechanisms of such an emission have never been well clarified. Recently, research in our laboratory has pointed out the importance played by conducting sites (particles and protrusions). A refined geometrical model, called superposed protrusions model has been proposed to explain the enhanced emission by local field enhancement. As a logical continuation, the present work aims at testing this model and, in the same time, investigating the means to suppress the emission where it is undesirable. Thus, we have showed: the cause of current fluctuations in a continuous field regime (DC), the identity of emission characteristics (β, A e ) in both radiofrequency (RF) and DC regimes, the effectiveness of a thermal treatment by extern high density electronic bombardment, the effectiveness of a mechanical treatment by high pressure rinsing with ultra pure water, the mechanisms and limits of an in situ RF processing. Furthermore, the electronic emission from insulating particles has also been studied concurrently with a spectral analysis of the associated luminous emission. Finally, the refined geometrical model for conducting sites is reinforced while another model is proposed for some insulating sites. Several emission suppressing treatments has been explored and validated. At last, the characteristic of a RF pulsed field emitted electron beam has been checked for the first time as a possible application of such a field emission. (author)
Energy Technology Data Exchange (ETDEWEB)
Muessig, S.; Oberndorfer, M.; Rice, D. [Rohoelaufsuchungs-AG, Wien (Austria); Soliman, K. [Montanuniversitaet Leoben (Austria)
2013-08-01
Currently, approximately 40% of world oil production comes from mature fields and the tendency is that this will increase with time. A significant portion of operational expenditures in mature oil fields is related to lifting costs including the cost of maintenance of the artificial lift equipment. In many cases additional, unnecessary, costs are incurred due to inadequate control of corrosion and sand production leading to premature failures of the equipment and thus to additional workover operations. In mature fields this can result in a significant loss of reserves when the production has to be abandoned prematurely because workover operations become uneconomic. In order to combat such losses of reserves RAG and its partners have developed fit-for-purpose technologies such as: continuous control of the liquid level in the annulus (i.e. bottom hole flowing pressure), innovative advanced sand control and longer lasting artificial lift equipment. On the basis of the 75 years old Zistersdorf oilfields the value of these developments in artificial lift technology is demonstrated. The Zistersdorf oilfields produce primarily from the compacted and fairly permeable 'Sarmat' sandstone formation which has many layers whereby the higher layers are poorly consolidated. The fields are currently producing from 33 producing wells some 6 900 m{sup 3} (Vn)/d gas and 48 t/d of oil at an average water cut of 97.1%. It will be shown that the implementation of the technologies described in combination with the in-house knowledge and the dedication of the field staff has extended considerably the mean time between failures of the equipment, reduced markedly the average yearly decline rate and thus extended the economic life expectancy of the fields and increased the ultimate recovery significantly.
Brushed permanent magnet DC MLC motor operation in an external magnetic field
Energy Technology Data Exchange (ETDEWEB)
Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G. [Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Physics, University of Alberta, 11322-89 Avenue, Edmonton, Alberta T6G 2G7 (Canada); Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada) and Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)
2010-05-15
Purpose: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. Methods: The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). Results: In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450{+-}10 G. The carriage motor tolerated up to 2000{+-}10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600{+-}10 G. Conclusions: The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the
Brushed permanent magnet DC MLC motor operation in an external magnetic field.
Yun, J; St Aubin, J; Rathee, S; Fallone, B G
2010-05-01
Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450 +/- 10 G. The carriage motor tolerated up to 2000 +/- 10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600 +/- 10 G. The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the tolerance levels determined, some form of
Brushed permanent magnet DC MLC motor operation in an external magnetic field
International Nuclear Information System (INIS)
Yun, J.; St Aubin, J.; Rathee, S.; Fallone, B. G.
2010-01-01
Purpose: Linac-MR systems for real-time image-guided radiotherapy will utilize the multileaf collimators (MLCs) to perform conformal radiotherapy and tumor tracking. The MLCs would be exposed to the external fringe magnetic fields of the linac-MR hybrid systems. Therefore, an experimental investigation of the effect of an external magnetic field on the brushed permanent magnet DC motors used in some MLC systems was performed. Methods: The changes in motor speed and current were measured for varying external magnetic field strengths up to 2000 G generated by an EEV electromagnet. These changes in motor characteristics were measured for three orientations of the motor in the external magnetic field, mimicking changes in motor orientations due to installation and/or collimator rotations. In addition, the functionality of the associated magnetic motor encoder was tested. The tested motors are used with the Varian 120 leaf Millennium MLC (Maxon Motor half leaf and full leaf motors) and the Varian 52 leaf MKII MLC (MicroMo Electronics leaf motor) including a carriage motor (MicroMo Electronics). Results: In most cases, the magnetic encoder of the motors failed prior to any damage to the gearbox or the permanent magnet motor itself. This sets an upper limit of the external magnetic field strength on the motor function. The measured limits of the external magnetic fields were found to vary by the motor type. The leaf motor used with a Varian 52 leaf MKII MLC system tolerated up to 450±10 G. The carriage motor tolerated up to 2000±10 G field. The motors used with the Varian 120 leaf Millennium MLC system were found to tolerate a maximum of 600±10 G. Conclusions: The current Varian MLC system motors can be used for real-time image-guided radiotherapy coupled to a linac-MR system, provided the fringe magnetic fields at their locations are below the determined tolerance levels. With the fringe magnetic fields of linac-MR systems expected to be larger than the tolerance
Attention operates uniformly throughout the classical receptive field and the surround
Verhoef, Bram-Ernst; Maunsell, John HR
2016-01-01
Shifting attention among visual stimuli at different locations modulates neuronal responses in heterogeneous ways, depending on where those stimuli lie within the receptive fields of neurons. Yet how attention interacts with the receptive-field structure of cortical neurons remains unclear. We measured neuronal responses in area V4 while monkeys shifted their attention among stimuli placed in different locations within and around neuronal receptive fields. We found that attention interacts uniformly with the spatially-varying excitation and suppression associated with the receptive field. This interaction explained the large variability in attention modulation across neurons, and a non-additive relationship among stimulus selectivity, stimulus-induced suppression and attention modulation that has not been previously described. A spatially-tuned normalization model precisely accounted for all observed attention modulations and for the spatial summation properties of neurons. These results provide a unified account of spatial summation and attention-related modulation across both the classical receptive field and the surround. DOI: http://dx.doi.org/10.7554/eLife.17256.001 PMID:27547989
Reversed field pinch operation with intelligent shell feedback control in EXTRAP T2R
Brunsell, P. R.; Kuldkepp, M.; Menmuir, S.; Cecconello, M.; Hedqvist, A.; Yadikin, D.; Drake, J. R.; Rachlew, E.
2006-11-01
Discharges in the thin shell reversed field pinch (RFP) device EXTRAP T2R without active feedback control are characterized by growth of non-resonant m = 1 unstable resistive wall modes (RWMs) in agreement with linear MHD theory. Resonant m = 1 tearing modes (TMs) exhibit initially fast rotation and the associated perturbed radial fields at the shell are small, but eventually TMs wall-lock and give rise to a growing radial field. The increase in the radial field at the wall due to growing RWMs and wall-locked TMs is correlated with an increase in the toroidal loop voltage, which leads to discharge termination after 3-4 wall times. An active magnetic feedback control system has been installed in EXTRAP T2R. A two-dimensional array of 128 active saddle coils (pair-connected into 64 independent m = 1 coils) is used with intelligent shell feedback control to suppress the m = 1 radial field at the shell. With feedback control, active stabilization of the full toroidal spectrum of 16 unstable m = 1 non-resonant RWMs is achieved, and TM wall locking is avoided. A three-fold extension of the pulse length, up to the power supply limit, is observed. Intelligent shell feedback control is able to maintain the plasma equilibrium for 10 wall times, with plasma confinement parameters sustained at values comparable to those obtained in thick shell devices of similar size.
Reversed field pinch operation with intelligent shell feedback control in EXTRAP T2R
International Nuclear Information System (INIS)
Brunsell, P.R.; Kuldkepp, M.; Menmuir, S.; Cecconello, M.; Hedqvist, A.; Yadikin, D.; Drake, J.R.; Rachlew, E.
2006-01-01
Discharges in the thin shell reversed field pinch (RFP) device EXTRAP T2R without active feedback control are characterized by growth of non-resonant m = 1 unstable resistive wall modes (RWMs) in agreement with linear MHD theory. Resonant m = 1 tearing modes (TMs) exhibit initially fast rotation and the associated perturbed radial fields at the shell are small, but eventually TMs wall-lock and give rise to a growing radial field. The increase in the radial field at the wall due to growing RWMs and wall-locked TMs is correlated with an increase in the toroidal loop voltage, which leads to discharge termination after 3-4 wall times. An active magnetic feedback control system has been installed in EXTRAP T2R. A two-dimensional array of 128 active saddle coils (pair-connected into 64 independent m = 1 coils) is used with intelligent shell feedback control to suppress the m = 1 radial field at the shell. With feedback control, active stabilization of the full toroidal spectrum of 16 unstable m = 1 non-resonant RWMs is achieved, and TM wall locking is avoided. A three-fold extension of the pulse length, up to the power supply limit, is observed. Intelligent shell feedback control is able to maintain the plasma equilibrium for 10 wall times, with plasma confinement parameters sustained at values comparable to those obtained in thick shell devices of similar size
Quantum double actions on operator algebras and orbifold quantum field theories
International Nuclear Information System (INIS)
Mueger, M.
1996-06-01
Starting from a local quantum field theory with an unbroken compact symmetry group G in 1+1 dimensional spacetime we construct disorder fields implementing gauge transformations on the fields (order variables) localized in a wedge region. Enlarging the local algebras by these disorder fields we obtain a nonlocal field theory, the fixpoint algebras of which under the appropriately extended action of the group G are shown to satisfy Haag duality in every simple sector. The specifically 1+1 dimensional phenomenon of violation of Haag duality of fixpoint nets is thereby clarified. In the case of a finite group G the extended theory is acted upon in a completely canonical way by the quantum double D(G) and satisfies R-matrix commutation relations as well as a Verlinde algebra. Furthermore, our methods are suitable for a concise and transparent approach to bosonization. The main technical ingredient is a strengthened version of the split property which should hold in all reasonable massive theories. In the appendices (part of) the results are extended to arbitary locally compact groups and our methods are adapted to chiral theories on the circle. (orig.)
Šimkanin, Ján; Kyselica, Juraj
2017-12-01
Numerical simulations of the geodynamo are becoming more realistic because of advances in computer technology. Here, the geodynamo model is investigated numerically at the extremely low Ekman and magnetic Prandtl numbers using the PARODY dynamo code. These parameters are more realistic than those used in previous numerical studies of the geodynamo. Our model is based on the Boussinesq approximation and the temperature gradient between upper and lower boundaries is a source of convection. This study attempts to answer the question how realistic the geodynamo models are. Numerical results show that our dynamo belongs to the strong-field dynamos. The generated magnetic field is dipolar and large-scale while convection is small-scale and sheet-like flows (plumes) are preferred to a columnar convection. Scales of magnetic and velocity fields are separated, which enables hydromagnetic dynamos to maintain the magnetic field at the low magnetic Prandtl numbers. The inner core rotation rate is lower than that in previous geodynamo models. On the other hand, dimensional magnitudes of velocity and magnetic fields and those of the magnetic and viscous dissipation are larger than those expected in the Earth's core due to our parameter range chosen.
Hoang, Ty; Swenson, Harry N.
1997-01-01
The Traffic Management Advisor (TMA), the sequence and schedule tool of the Center/TRACON Automation System (CTAS), was evaluated at the Fort Worth Center (ZFW) in the summer of 1996. This paper describes the challenges encountered during the various phases of the TMA field evaluation, which included system (hardware and software) installation, personnel training, and data collection. Operational procedures were developed and applied to the evaluation process that would ensure air safety. The five weeks of field evaluation imposed minimal impact on the hosting facility and provided valuable engineering and human factors data. The collection of data was very much an opportunistic affair, due to dynamic traffic conditions. One measure of the success of the TMA evaluation is that, rather than remove TMA after the evaluation until it could be fully implemented, the prototype TMA is in continual use at ZFW as the fully operational version is readied for implementation.
Design and field operation of 1175 MW steam turbine for Ohi Nuclear Power Station
International Nuclear Information System (INIS)
Hirota, Yoshio; Nakagami, Yasuo; Fujii, Hisashi; Shibanai, Hirooki.
1980-01-01
Two 1175 MW steam turbine and generator units have been successfully in commercial operation since March 1979 and December 1979 respectively at Ohi Nuclear Power Station of the Kansai Electric Power Company. Those units, the largest in their respective outputs in Japan, have also such remarkable design features as two-stage reheat, nozzle governing turbine, water cooled generator stator and turbine-driven feedwater pumps. This paper covers design features and some topics of various pre-operational tests of the above-mentioned units. (author)
Design and field operation of 1175 MW steam turbine for Ohi Nuclear Power Station
International Nuclear Information System (INIS)
Hirota, Y.; Nakagami, Y.; Fujii, H.; Shibanai, H.
1980-01-01
Two 1,175 MW steam turbine and generator units have been successfully in commercial operation since March 1979 and December 1979 respectively at Ohi Nuclear Power Station of the Kansai Electric Power Company. Those units, the largest in their respective outputs in Japan, have also such remarkable design features as two-stage reheat, nozzle governing turbine, water cooled generator stator and turbine-driven feedwater pumps. This paper covers design features and some topics of various pre-operational tests of the above-mentioned units. (author)
Evaluation of the new French operational weather radar product for the field of urban hydrology
EMMANUEL, Isabelle; ANDRIEU, Hervé; TABARY, P
2012-01-01
The main objective of this paper is to evaluate, at the urban scale, the accuracy of the new French operational radar processing chain deployed within the French operational weather radar network. Such an evaluation is conducted by comparing radar data resulting from this processing chain (with a 1-km² resolution) to rain gauge data at four different time scales, i.e. 5,15, 30 and 60 min. These data are supplied by the Trappes Radar Station, located 30 km southwest of Paris. A total of 69 rai...
Some applicationS of non-Hermitian operators in quantum mechanics and quantum field theory
International Nuclear Information System (INIS)
Recami, E.; Rodrigues, W.A. Jr.; Smrz, P.
1983-01-01
Due to the possibility of rephrasing it in terms of Lie-admissible algebras, some work done in the past in collaboration with A., Agodi, M., Baldo and V.S., Olkhovsky is here reported. Such work led to the introduction of non-Hermitian operators in (classical and relativistic) quantum theory. In particular: (i) the association of unstable states (decaying 'Resonances') with the eigenvectors of non-Hermitian hamiltonians; (ii) the problem of the four position operators for relativistic spin-zero particles are dealth with
International Nuclear Information System (INIS)
Hampel, R.; Schwedusch, F.
1990-01-01
The high requirements on NPP operation to be nuclear safe and optimal with regard to electricity production need high redundancy and diversity in the instrumentation being implemented. As a contribution of the Zittau Technical University to development of alternative measuring techniques for primary coolant circuit monitoring, application of gamma-field measurement for determination of reactor power and power distribution is described. Theoretical foundation and conclusions herefrom derived are explained. (author)
International Nuclear Information System (INIS)
Mole, C.J.; Haller, H.E. III.
1977-01-01
Two parallel magnetic flux paths are provided in a dynamoelectric machine having a superconductive field winding. A first, or main, magnetic flux path includes at least one area of nonferromagnetic or diamagnetic material. A second, or shunt, magnetic flux path prevents the relatively low frequency ac flux present during starting or asynchronous operation of the machine, when used as an ac motor, from penetrating the superconductive winding
Zeng, Yue; Tang, Fei; Zhai, Yadong; Wang, Xiaohao
2017-09-01
The traditional operation mode of high-field Asymmetric Waveform Ion Mobility Spectrometry (FAIMS) uses a one-way radio frequency (RF) voltage input as the dispersion voltage. This requires a high voltage input and limits power consumption reduction and miniaturization of instruments. With higher dispersion voltages or larger compensation voltages, there also exist problems such as low signal intensity or the fact that the dispersion voltage is no longer much larger than the compensation voltage. In this paper, a differential-RF-driven operation mode of FAIMS is proposed. The two-way RF is used to generate the dispersion field, and a phase difference is added between the two RFs to generate a single step waveform field. Theoretical analysis, and experimental results from an ethanol sample, showed that the peak positions of the ion spectra changed linearly (R 2 = 0.9992) with the phase difference of the two RFs in the differential-RF-driven mode and that the peak intensity of the ion spectrum could be enhanced by more than eight times for ethanol ions. In this way, it is possible to convert the ion spectrum peaks outside the separation or compensation voltage range into a detectable range, by changing the phase difference. To produce the same separation electric field, the high-voltage direct current input voltage can be maximally reduced to half of that in the traditional operation mode. Without changing the drift region size or drift condition, the differential-RF-driven operation mode can reduce power consumption, increase signal-to-noise ratio, extend the application range of the dispersion voltage and compensation voltage, and improve FAIMS detection performance.
International Nuclear Information System (INIS)
Souques, M.; Lambrozo, J.; Frank, R.; Himbert, C.
2002-01-01
The aim of this study was to assess the changes in the behavior of cardiac pacemakers exposed to 50 and 60 Hz magnetic fields generated by industrial current and 20 to 50 khz magnetic fields generated by a household in a booming period - the induction cook top - and to study the incidence of these changes in a population of subjects with implanted pacemakers. This will enabled to give patients advices about dealing with electric transport lines and facilities and with induction cook tops and to advise manufacturers about the risks involved
Directory of Open Access Journals (Sweden)
Khaled Sadek
2009-10-01
Full Text Available In this paper, the reliability of capacitive shunt RF MEMS switches have been investigated using three dimensional (3D coupled multiphysics finite element (FE analysis. The coupled field analysis involved three consecutive multiphysics interactions. The first interaction is characterized as a two-way sequential electromagnetic (EM-thermal field coupling. The second interaction represented a one-way sequential thermal-structural field coupling. The third interaction portrayed a two-way sequential structural-electrostatic field coupling. An automated substructuring algorithm was utilized to reduce the computational cost of the complicated coupled multiphysics FE analysis. The results of the substructured FE model with coupled field analysis is shown to be in good agreement with the outcome of previously published experimental and numerical studies. The current numerical results indicate that the pull-in voltage and the buckling temperature of the RF switch are functions of the microfabrication residual stress state, the switch operational frequency and the surrounding packaging temperature. Furthermore, the current results point out that by introducing proper mechanical approaches such as corrugated switches and through-holes in the switch membrane, it is possible to achieve reliable pull-in voltages, at various operating temperatures. The performed analysis also shows that by controlling the mean and gradient residual stresses, generated during microfabrication, in conjunction with the proposed mechanical approaches, the power handling capability of RF MEMS switches can be increased, at a wide range of operational frequencies. These design features of RF MEMS switches are of particular importance in applications where a high RF power (frequencies above 10 GHz and large temperature variations are expected, such as in satellites and airplane condition monitoring.
International Nuclear Information System (INIS)
Wu, Q X; Zhao, T S; Chen, R; Yang, W W
2010-01-01
Conventional direct methanol fuel cells (DMFCs) have to operate with excessively diluted methanol solutions to limit methanol crossover and its detrimental consequences. Operation with such diluted methanol solutions not only results in a significant penalty in the specific energy of the power pack, limiting the runtime of this type of fuel cell, but also lowers the cell performance and operating stability. In this paper, a microfluidic-structured anode flow field for passive DMFCs with neither liquid pumps nor gas compressors/blowers is developed. This flow field consists of plural micro flow passages. Taking advantage of the liquid methanol and gas CO 2 two-phase counter flow, the unique fluidic structure enables the formation of a liquid–gas meniscus in each flow passage. The evaporation from the small meniscus in each flow passage can lead to an extremely large interfacial mass-transfer resistance, creating a bottleneck of methanol delivery to the anode CL. The fuel cell tests show that the innovative flow field allows passive DMFCs to achieve good cell performance with a methanol concentration as high as 18.0 M, increasing the specific energy of the DMFC system by about five times compared with conventional designs.
Pruissen, O.P. van; Kok, J.K.; Eisma, A.
2015-01-01
The Dutch electricity infrastructure is challenged by the deployment of large numbers of heat pumps in newly-built domestic residences. An example is the apartment complex of Couperus in The Hague where 300 apartments are heated by individual heat pumps. This building was operated as a Virtual Power
Worldwide C-17 Availability to Support 82nd Airborne Operations from Fort Bragg/Pope Field
2016-11-06
elsewhere. Now, with operational tempo in the Middle East slowing, the 82nd must analyze how best to leverage its capabilities in support of the GRF...www.rand.org/pubs/research_reports/RR1161.html Stiner, Carl, and Daniel R. Schroeder, “The Army and Joint Forcible Entry,” Army Magazine Vol. 59, No.11
How Effective was Field Marshal William Slim as an Operational Artist?
2012-05-17
Division having conducted an unidentified flanking maneuver to threaten his Division rear area. Slim, bedridden with dysentery, was also surprised at...Ashes: The Indian Army in the Burma Campaign. Westport: Praeger Publishers, 2003. Matheny, Michael R . The Roots of Modern American Operational Art
Limited field investigation report for the 100-HR-2 Operable Unit
International Nuclear Information System (INIS)
1994-09-01
This report summarizes the data collection and analysis activities conducted during the 100-HR-2 Operable Unit investigative phase and the associated qualitative risk assessment (QRA). The 100-HR-2 Operable Unit contains solid waste burial grounds, an ash pit, bum pits, electrical facilities, septic systems, and support facilities. All known and suspected areas of contamination were classified as solid waste burial grounds or low-priority waste sites based on the collective knowledge of the operable unit managers (representatives from the US Department of Energy [DOE], the US Environmental Protection Agency [EPA], and Washington Department of Ecology [Ecology]) during the preparation of the 100-HR-2 Operable Unit work plan (DOE/RL 1993f). Solid waste burial grounds were judged to pose sufficient risk(s), through one or more pathways, to require evaluation for an interim remedial measure (IRM) as per the Hanford Past-Practice Strategy (HPPS) (DOE/RL 1991) and negotiations with DOE, EPA, and Ecology. An IRM is intended to achieve remedies that are likely to lead to a final record of decision. Low-priority sites are those judged not to pose significant risk to require the streamlined evaluation. There were six low-priority waste sites and seven solid waste burial grounds identified. The investigative phase was conducted in accordance with the RCRA Facility Investigation/Corrective Measures Study Work Plan for the 100-HR-2 Operable Unit (DOE/RL 1993f). The QRA was performed in accordance with the Hanford Site Baseline Risk Assessment Methodology (DOE/RL 1993b) and the recommendations incorporate the strategies of the HPPS. The purpose of this report is to: (1) provide a summary of site investigative activities; (2) refine the conceptual exposure model (as needed); (3) identify chemical- and location-specific corrective action requirements; and (4) provide a human health and ecological QRA associated with solid waste burial grounds
Synthesis and atmospheric pressure field emission operation of W18O49 nanowires
Agiral, A.; Gardeniers, Johannes G.E.
2008-01-01
Tungsten oxide W18O49 nanorods with diameters of 15−20 nm were grown on tungsten thin films exposed to ethene and nitrogen at 700 °C at atmospheric pressure. It was found that tungsten carbide formation enhances nucleation and growth of nanorods. Atmospheric pressure field emission measurements in
Sharma, A.; Mathijssen, S.G.J.; Bobbert, P.A.; Leeuw, de D.M.
2011-01-01
During prolonged application of a gate bias, organic field-effect transistors show a gradual shift of the threshold voltage towards the applied gate bias voltage. The shift follows a stretched-exponential time dependence governed by a relaxation time. Here, we show that a thermodynamic analysis
California State Univ., Sacramento. Dept. of Civil Engineering.
The objective of this instructor's guide is to help provide students with knowledge and skills for employment in the field of wastewater treatment. Included in each chapter outline are: (1) objectives, (2) instructional approach, (3) answers to the objective test in the student's text, and (4) an explanation of these answers. The material…
California State Univ., Sacramento. Dept. of Civil Engineering.
The objective of this instructor's guide is to help provide students with knowledge and skills for employment in the field of wastewater treatment. Included in each chapter outline are: (1) objectives, (2) instructional approach, (3) answers to the objective test in the student's text, and (4) an explanation of these answers. The material…
A differential equation for Lerch's transcendent and associated symmetric operators in Hilbert space
International Nuclear Information System (INIS)
Kaplitskii, V M
2014-01-01
The function Ψ(x,y,s)=e iy Φ(−e iy ,s,x), where Φ(z,s,v) is Lerch's transcendent, satisfies the following two-dimensional formally self-adjoint second-order hyperbolic differential equation, where s=1/2+iλ. The corresponding differential expression determines a densely defined symmetric operator (the minimal operator) on the Hilbert space L 2 (Π), where Π=(0,1)×(0,2π). We obtain a description of the domains of definition of some symmetric extensions of the minimal operator. We show that formal solutions of the eigenvalue problem for these symmetric extensions are represented by functional series whose structure resembles that of the Fourier series of Ψ(x,y,s). We discuss sufficient conditions for these formal solutions to be eigenfunctions of the resulting symmetric differential operators. We also demonstrate a close relationship between the spectral properties of these symmetric differential operators and the distribution of the zeros of some special analytic functions analogous to the Riemann zeta function. Bibliography: 15 titles
Energy Technology Data Exchange (ETDEWEB)
Jemcov, A.; Matovic, M.D. [Queen`s Univ., Kingston, Ontario (Canada)
1996-12-31
This paper examines the sparse representation and preconditioning of a discrete Steklov-Poincare operator which arises in domain decomposition methods. A non-overlapping domain decomposition method is applied to a second order self-adjoint elliptic operator (Poisson equation), with homogeneous boundary conditions, as a model problem. It is shown that the discrete Steklov-Poincare operator allows sparse representation with a bounded condition number in wavelet basis if the transformation is followed by thresholding and resealing. These two steps combined enable the effective use of Krylov subspace methods as an iterative solution procedure for the system of linear equations. Finding the solution of an interface problem in domain decomposition methods, known as a Schur complement problem, has been shown to be equivalent to the discrete form of Steklov-Poincare operator. A common way to obtain Schur complement matrix is by ordering the matrix of discrete differential operator in subdomain node groups then block eliminating interface nodes. The result is a dense matrix which corresponds to the interface problem. This is equivalent to reducing the original problem to several smaller differential problems and one boundary integral equation problem for the subdomain interface.
International Nuclear Information System (INIS)
Moriyama, S.; Nakamura, Y.; Nagao, A.; Jotaki, E.; Nakamura, K.; Hiraki, N.; Itoh, S.
1990-01-01
Ultra-long pulse operation (>3 min) was achieved on the superconducting high field tokamak TRIAM-1M. In this operation, the plasma current was maintained with a relatively peaked current distribution by the 2.45 GHz radiofrequency power (P RF ≤ 35 kW) alone. A stationary plasma with a driven current of up to 35 kA and a line averaged electron density of up to 3x10 12 cm -3 was produced by precise plasma position and gas feed control. The extremely long discharge showed the interesting characteristics that the high temperatures of about 1 keV for the electrons and about 0.5 keV for the ions were kept almost constant during steady state current drive and that there was no impurity accumulation which could have a fatally adverse effect on steady state tokamak operation. (author). 16 refs, 17 figs
An ionization pressure gauge with LaB6 emitter for long-term operation in strong magnetic fields
Wenzel, U.; Pedersen, T. S.; Marquardt, M.; Singer, M.
2018-03-01
We report here on a potentially significant improvement in the design of neutral pressure gauges of the so-called ASDEX-type which were first used in the Axially Symmetric Divertor EXperiment (ASDEX). Such gauges are considered state-of-the-art and are in wide use in fusion experiments, but they nonetheless suffer from a relatively high failure rate when operated at high magnetic field strengths for long times. This is therefore a significant concern for long-pulse, high-field experiments such as Wendelstein 7-X (W7-X) and ITER. The new design is much more robust. The improvement is to use a LaB6 crystal instead of a tungsten wire as the thermionic emitter of electrons in the gauge. Such a LaB6 prototype gauge was successfully operated for a total of 60 h in B = 3.1 T, confirming the significantly improved robustness of the new design and qualifying it for near-term operation in W7-X. With the LaB6 crystal, an order of magnitude reduction in heating current is achieved, relative to the tungsten filament based gauges, from 15-20 A to 1-2 A. This reduces the Lorenz forces and the heating power by an order of magnitude also and is presumably the reason for the much improved robustness. The new gauge design, test environment setup at the superconducting magnet, and results from test operation are described.
Energy Technology Data Exchange (ETDEWEB)
Harkness, L.J., E-mail: ljh@ns.ph.liv.ac.u [Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Boston, A.J.; Boston, H.C.; Cole, P.; Cresswell, J.R.; Filmer, F.; Jones, M.; Judson, D.S.; Nolan, P.J.; Oxley, D.C.; Sampson, J.A.; Scraggs, D.P.; Slee, M.J. [Department of Physics, University of Liverpool, Liverpool L69 7ZE (United Kingdom); Bimson, W.E.; Kemp, G.J. [MARIARC, University of Liverpool, Liverpool L69 3GE (United Kingdom); Groves, J.; Headspith, J.; Lazarus, I.; Simpson, J. [STFC Daresbury Laboratory, Daresbury, Warrington WA4 4AD (United Kingdom); Cooper, R.J. [Joint Institute for Heavy Ion Research, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6371 (United States)
2011-05-11
Nuclear medical imaging modalities such as positron emission tomography and single photon emission computed tomography are used to probe physiological functions of the body by detecting gamma rays emitted from biologically targeted radiopharmaceuticals. A system which is capable of simultaneous data acquisition for nuclear medical imaging and magnetic resonance imaging is highly sought after by the medical imaging community. Such a device could provide a more complete medical insight into the functions of the body within a well-defined structural context. However, acquiring simultaneous nuclear/MRI sequences are technically challenging due to the conventional photomultiplier tube readout employed by most existing scintillator detector systems. A promising solution is a nuclear imaging device composed of semiconductor detectors that can be operated with a standard MRI scanner. However, the influence of placing a semiconductor detector such as high purity germanium (HPGe) within or close to the bore of an MRI scanner, where high magnetic fields are present, is not well understood. In this paper, the performance of a HPGe detector operating in a high strength static (B{sub S}) MRI field along with fast switching gradient fields and radiofrequency from the MRI system has been assessed. The influence of the B{sub S} field on the energy resolution of the detector has been investigated for various positions and orientations of the detector within the magnetic field. The results have then been interpreted in terms of the influence of the B{sub S} field on the charge collection properties. MRI images have been acquired with the detector situated at the entrance of the MRI bore to investigate the effects of simultaneous data acquisition on detector performance and MRI imaging.
Limited field investigation report for the 100-HR-2 Operable Unit
International Nuclear Information System (INIS)
1995-07-01
This report summarizes the data collection and analysis activities conducted during the 100-HR-2 Operable Unit investigative phase and the associated qualitative risk assessment. The 100-HR-2 Operable Unit contains solid waste burial grounds, an ash pit, burn pits, electrical facilities, septic systems, and support facilities. All known and suspected areas of contamination were classified as solid waste burial grounds or low-priority waste sites based on the collective knowledge of the operable unit managers (representatives from the US Department of Energy, the US Environmental Protection Agency, and Washington State Department of Ecology during the preparation of the 100-HR-2 Operable Unit Work Plan (DOE-RL 1993f). Solid waste burial grounds were judged to pose sufficient risk(s), through one or more pathways, to require evaluation for an interim remedial measure as per the Hanford Past-Practice Strategy (DOE-RL 1991) and negotiations with the Department of Energy, US Environmental Protection Agency, and Washington State Department of Ecology. An interim remedial measure is intended to achieve remedies that are likely to lead to a final record of decision. Low-priority sites are those judged not to pose significant risk to require the streamlined evaluation. There were six low-priority waste sites and seven solid waste burial grounds identified. The purpose of this report is to: (1) provide a summary of site investigative activities; (2) refine the conceptual exposure model (as needed); (3) identify chemical- and location-specific corrective action requirements; and 4) provide a human health and ecological QRA associated with solid waste burial grounds
Field Testing Pulsed Power Inverters in Welding Operations to Control Heavy Metal Emissions
2009-12-01
Aluminum, zinc , and barium were also present, but they are believed to be an artifact of the CI substrate filter material.) Other metals that appear in the...OPERATIONS As noted earlier, PPI technology is promoted as producing less metal-bearing particulates because less slag and spatter take place. This is...2) Also, less slag and spatter should result in reduced welding time. In addition, PPI reportedly will generate less ozone, carbon monoxide, and
Co-operative projects with AECL in the fields of hydrogeology and geochemistry
International Nuclear Information System (INIS)
1985-01-01
The report covers collaborative study with Atomic Energy of Canada Limited on geological aspects of waste disposal in crystalline rocks. A field test of the sinusoidal hydraulic pressure pulse method was carried out at the URL site to try to define hydraulic properties of major horizontal fractures. The trials were generally successful and observable sine and square wave signals were transmitted. Owing to the limited scale of the programme, and some equipment problems, the results proved difficult to interpret, although the speed and flexibility of the method was demonstrated. A second aspect of collaboration was to be the field comparison of the AECL and NERC/BGS borehole geochemical probes. In the event, the AECL probe development programme was curtailed and a Swedish design selected for purchase. Effort thus switched to technical comparison of the SGAB probe with the NERC/BGS design. Since both are still at various development points the collaboration was limited to technical exchange. The results are presented. (author)
A thin film passive magnetic field sensor operated at 425 MHz
Li, Bodong; Kosel, Jü rgen
2013-01-01
A passive, magnetic field sensor consisting of a 425 MHz surface acoustic wave (SAW) transponder loaded with a giant magnetoimpedance (GMI) element is developed. The transponder, consisting of two interdigital transducers (IDTs) and the GMI element, a multilayer structure composed of Ni80Fe 20/Cu/Ni80Fe20, are fabricated on a 128° Y-X cut LiNbO3 substrate. The integrated sensor is characterized with a network analyzer through an S-parameter measurement. Upon the application of a magnetic field, a maximum amplitude change and phase shift of 2.7 dB and 20 degree, respectively, are observed. Within the linear region, the magnetic sensitivity is 3870 dB/T and the resolution is 1.3 μT. © 2013 IEEE.
A thin film passive magnetic field sensor operated at 425 MHz
Li, Bodong
2013-06-01
A passive, magnetic field sensor consisting of a 425 MHz surface acoustic wave (SAW) transponder loaded with a giant magnetoimpedance (GMI) element is developed. The transponder, consisting of two interdigital transducers (IDTs) and the GMI element, a multilayer structure composed of Ni80Fe 20/Cu/Ni80Fe20, are fabricated on a 128° Y-X cut LiNbO3 substrate. The integrated sensor is characterized with a network analyzer through an S-parameter measurement. Upon the application of a magnetic field, a maximum amplitude change and phase shift of 2.7 dB and 20 degree, respectively, are observed. Within the linear region, the magnetic sensitivity is 3870 dB/T and the resolution is 1.3 μT. © 2013 IEEE.
Direct approach to operator conformal constructions: from fermions to primary fields
International Nuclear Information System (INIS)
Halpern, M.B.
1989-01-01
I discuss the direct solution of Sugawara and coset constructions, including a path to construction of the primary fields. The basic tools are (1) a construction of affine-conformal highest-weight states, pretensors and tensors form quantum-irreducible representations of the currents of affine g, and (2) construction of primary fields by factorization and boosting of the pretensors. Large classes of pretensors are easily obtained in fermionic constructions, and guesswork is minimized with factorization of bosonized fermionic pretensors: The simplest case constructs conformal-weights h g =mN(n--N)/2n of SU m (n) and h K =mN(n--N)/n of SU m (n)direct-product SU m (n)/SU 2m (n) and extension to simply-laced g is clear. More general cases are left for future study. copyright Academic Prss, Inc. 1989
Design and operation of a coaxial plasma gun at magnetic fields exceeding 0.5 megagauss
International Nuclear Information System (INIS)
Conte, D.; Bird, G.; Boyer, C.; Davis, J.; Seiler, S.; Turchi, P.
1981-01-01
The use of coaxial plasma guns to accumulate and concentrate electromagnetic and kinetic energy at high currents and power flux levels has been examined experimentally. For these studies, apparatus was designed to employ magnetic fields approaching 1MG, using the AFWL Shiva capacitor bank as the current source (1.9 MJ, 120 KV). The design divided the system into two major component regions: 1) a reusable cylindrical transition to the Shiva bank, an 2) disposable guns and feed plates
Energy Technology Data Exchange (ETDEWEB)
Mingareev, R Sh; Vakhitov, G G; Sultanov, S A
1968-11-01
Each year about 130 million cu m of cold water are injected into this field. Since cold water can lower reservoir temperature, increase oil viscosity, deposit paraffin in the formation, and reduce oil recovery, a thermal survey of this field was conducted. The survey showed that the average reservoir temperature was not reduced by cold-water injection for 15 yr. However, local cooling was observed at distances less than 400 m from the water injection well. Through these wells more than 4 PV of water have passed. The thermal front lags 1,500 m behind the advancing water front. For this reason, cold-water injection does not reduce oil recovery where there is uniform advance of the floodwater. When the formation is heterogeneous so that water advances more rapidly in high-permeability sand than in adjoining low-permeability sand, then the cooling effect can reduce oil recovery. For this reason, it is advisable to force water into the entire interval of the oil formation. An isotherm map of the Romashkino field is shown.
International Nuclear Information System (INIS)
Almberg, S. S.; Frengen, J.; Lindmo, T.
2012-01-01
Purpose: To compare dosimetric characteristics of 6 MV photon fields originating from a linear accelerator operating with (FF) and without (FFF) a flattening-filter. The main objective is to establish a FFF model that results in similar depth-dose and build-up profiles as the original FF model, and subsequently estimate and compare out-of-field dose distributions. Methods: The EGSnrc Monte Carlo user codes BEAMnrc and DOSXYZnrc are used for photon beam simulations of an Elekta linear accelerator and dose calculations in a water phantom, respectively. Three beam models were analyzed: (1) the conventional linear accelerator with the flattening-filter in place and incident electron energy 6.45 MeV (FF 6.45 MeV), (2) similar flattening-filter-free model (FFF 6.45 MeV), and (3) as (2) but with increased electron energy (FFF 8.0 MeV). The field size 5 × 5 cm 2 was used for characterization of dose output, depth dose profiles, and photon spectrum. The field size 40 × 40 cm 2 was used for characterization of cross-field photon energy, photon fluence, and dose distributions. Out-of-field dose distributions were analyzed in both in-plane and cross-plane directions for 5 × 5 cm 2 and 10 × 10 cm 2 fields. Results: Comparable depth dose distributions, including the build-up region, for FF and FFF fields were achieved by increasing the electron energy from 6.45 MeV to 8.0 MeV for the FFF beam. The FFF beams result in reduced out-of-field dose compared to the FF beam: the reduction was most apparent in the cross-plane direction and more pronounced by the FFF 8.0 MeV beam compared to the FFF 6.45 MeV beam. Differences in out-of-field dose due to direction (in-plane vs cross-plane) were up to 40% for the FF beam; this effect was significantly reduced for the FFF beams. As the flattening-filter is a major source of contaminating electrons, superficial out-of-field dose was expected, and was found to be, reduced for FFF beams. Conclusions: The build-up and depth
Almberg, S S; Frengen, J; Lindmo, T
2012-08-01
To compare dosimetric characteristics of 6 MV photon fields originating from a linear accelerator operating with (FF) and without (FFF) a flattening-filter. The main objective is to establish a FFF model that results in similar depth-dose and build-up profiles as the original FF model, and subsequently estimate and compare out-of-field dose distributions. The EGSnrc Monte Carlo user codes BEAMnrc and DOSXYZnrc are used for photon beam simulations of an Elekta linear accelerator and dose calculations in a water phantom, respectively. Three beam models were analyzed: (1) the conventional linear accelerator with the flattening-filter in place and incident electron energy 6.45 MeV (FF 6.45 MeV), (2) similar flattening-filter-free model (FFF 6.45 MeV), and (3) as (2) but with increased electron energy (FFF 8.0 MeV). The field size 5 × 5 cm(2) was used for characterization of dose output, depth dose profiles, and photon spectrum. The field size 40 × 40 cm(2) was used for characterization of cross-field photon energy, photon fluence, and dose distributions. Out-of-field dose distributions were analyzed in both in-plane and cross-plane directions for 5 × 5 cm(2) and 10 × 10 cm(2) fields. Comparable depth dose distributions, including the build-up region, for FF and FFF fields were achieved by increasing the electron energy from 6.45 MeV to 8.0 MeV for the FFF beam. The FFF beams result in reduced out-of-field dose compared to the FF beam: the reduction was most apparent in the cross-plane direction and more pronounced by the FFF 8.0 MeV beam compared to the FFF 6.45 MeV beam. Differences in out-of-field dose due to direction (in-plane vs cross-plane) were up to 40% for the FF beam; this effect was significantly reduced for the FFF beams. As the flattening-filter is a major source of contaminating electrons, superficial out-of-field dose was expected, and was found to be, reduced for FFF beams. The build-up and depth-dose characteristics of a conventional "6 MV" beam
International Nuclear Information System (INIS)
Coman, Ioana; Teschner, Joerg
2015-05-01
Non-perturbative aspects of N=2 supersymmetric gauge theories of class S are deeply encoded in the algebra of functions on the moduli space M flat of at SL(N)-connections on Riemann surfaces. Expectation values of Wilson and 't Hooft line operators are related to holonomies of flat connections, and expectation values of line operators in the low-energy effective theory are related to Fock-Goncharov coordinates on M flat . Via the decomposition of UV line operators into IR line operators, we determine their noncommutative algebra from the quantization of Fock-Goncharov Laurent polynomials, and find that it coincides with the skein algebra studied in the context of Chern-Simons theory. Another realization of the skein algebra is generated by Verlinde network operators in Toda field theory. Comparing the spectra of these two realizations provides non-trivial support for their equivalence. Our results can be viewed as evidence for the generalization of the AGT correspondence to higher-rank class S theories.
Energy Technology Data Exchange (ETDEWEB)
Liu, Ning [The Boeing Company, Canoga Park, CA (United States); Rutherford, Phil [The Boeing Company, Canoga Park, CA (United States); Dassler, David [The Boeing Company, Canoga Park, CA (United States)
2012-09-01
This Annual Site Environmental Report (ASER) for 2011 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, operation and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward environmental restoration and decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2011 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.
Energy Technology Data Exchange (ETDEWEB)
Liu, Ning [The Boeing Company, Canoga Park, CA (United States); Rutherford, Phil [The Boeing Company, Canoga Park, CA (United States); Dassler, David [The Boeing Company, Canoga Park, CA (United States)
2013-09-01
This Annual Site Environmental Report (ASER) for 2012 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, operation and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward environmental restoration and decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2012 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.
Energy Technology Data Exchange (ETDEWEB)
Djurabekova, Flyura, E-mail: flyura.djurabekova@helsinki.fi; Ruzibaev, Avaz; Parviainen, Stefan [Helsinki Institute of Physics and Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 Helsinki (Finland); Holmström, Eero [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland); Department of Earth Sciences, Faculty of Maths and Physical Sciences, UCL Earth Sciences, Gower Street, London WC1E 6BT (United Kingdom); Hakala, Mikko [Department of Physics, University of Helsinki, P.O. Box 64, FIN-00014 Helsinki (Finland)
2013-12-28
Metal surfaces operated under high electric fields produce sparks even if they are held in ultra high vacuum. In spite of extensive research on the topic of vacuum arcs, the mystery of vacuum arc origin still remains unresolved. The indications that the sparking rates depend on the material motivate the research on surface response to extremely high external electric fields. In this work by means of density-functional theory calculations we analyze the redistribution of electron density on (100) Cu surfaces due to self-adatoms and in presence of high electric fields from −1 V/nm up to −2 V/nm (−1 to −2 GV/m, respectively). We also calculate the partial charge induced by the external field on a single adatom and a cluster of two adatoms in order to obtain reliable information on charge redistribution on surface atoms, which can serve as a benchmarking quantity for the assessment of the electric field effects on metal surfaces by means of molecular dynamics simulations. Furthermore, we investigate the modifications of work function around rough surface features, such as step edges and self-adatoms.
International Nuclear Information System (INIS)
Mery, P.
1977-01-01
The operator and matrix Pade approximation are defined. The fact that these approximants can be derived from the Schwinger variational principle is emphasized. In potential theory, using this variational aspect it is shown that the matrix Pade approximation allow to reproduce the exact solution of the Lippman-Schwinger equation with any required accuracy taking only into account the knowledge of the first two coefficients in the Born expansion. The deep analytic structure of this variational matrix Pade approximation (hyper Pade approximation) is discussed
Cost effective solutions for field development. System supplier approach to projects and operations
International Nuclear Information System (INIS)
Moe, P.O.
1994-01-01
The conference paper outlines the most important elements for a new approach to project realisation that enable a cost reduction of 30-50% compared to conventional methods. The achievements are based on studies and evaluations to the Norwegian Vigdis development project. The system elements covered are the electrical and automation systems including safety and process control and all traditional phases of a project from concept design to the operational phase. The concept involves new principles for project execution where traditional borderlines and interfaces between the various participants have been redefined. Management attention has been verified as an important prerequisite for a successful implementation of this strategy. 2 figs
International co-operation in the nuclear field. Europe and OCDE countries
International Nuclear Information System (INIS)
Strohl, P.
1981-05-01
This report highlights the political factors underlying nuclear cooperation in the European context. It analyses the institutional structure for such cooperation and describes the different vocations of international organisations in the nuclear field (NEA, IAEA, Euratom). Finally the report gives concrete examples of international nuclear cooperation, with an emphasis on its legal aspects. (NEA) []Le present expose fait ressortir les facteurs politiques de la cooperation nucleaire notamment dans le contexte europeen. Il analyse la structure institutionnelle de cette cooperation et evoque les differentes vocations des organismes internationaux dans le domaine nucleaire (AEN, AIEA, Euratom). Il donne enfin des exemples concrets en mettant l'accent sur ses aspects juridiques
Energy Technology Data Exchange (ETDEWEB)
Watanabe, T [Center for Coal Utilization, Japan, Tokyo (Japan); Takanishi, K [Electric Power Development Co. Ltd., Tokyo (Japan)
1996-09-01
At the Wakamatsu Coal Utilization Research Center, the verification test was conducted of atmospheric pressure fluidized bed boilers and ultra-high temperature turbines. The Wakamatsu PFBC (pressurized fluidized bed combustion) is a combined cycle power generation system combining steam turbine power generation in which the turbine is driven by steam generated from the fluidized bed boiler installed inside the pressure vessel and gas turbine power generation in which high temperature/pressure exhaust gas is used from the boiler, having a total output of 71 MW. The operation started in fiscal 1995, stopped due to damage of the tube of CTF (ceramic tube filter), and is now continuing after the repair. As a result of the test conducted in fiscal 1995, it was confirmed in the two-stage cyclone test that the diameter of ash particle and cyclone efficiency change by kind of coal and amount of limestone and that by coal kind gas turbine blades show different states of abrasion, indicating greater abrasion when there is much SiO2 in ash. As a result of the continued high load operation of CTF, ash blockade inside the tube occurred and tube damage was generated by thermal shock, etc. 5 figs., 4 tabs.
International Nuclear Information System (INIS)
Lazanu, I.; Lazanu, S.
2004-01-01
Particle physics makes its greatest advances with experiments at the highest energies. The way to advance to a higher energy regime is through hadron colliders, or through non-accelerator experiments, as for example the space astroparticle missions. In the near future, the Large Hadron Collider (LHC) will be operational, and beyond that, its upgrades: the Super-LHC (SLHC) and the hypothetical Very Large Hadron Collider (VLHC). At the present time, there are no detailed studies for future accelerators, except those referring to LHC. For the new hadron collider LHC and some of its updates in luminosity and energy, the silicon detectors could represent an important option, especially for the tracking system and calorimetry. The main goal of this paper is to analyse the expected long-time degradation of the silicon as material and for silicon detectors, during continuous radiation, in these hostile conditions. The behaviour of silicon in relation to various scenarios for upgrade in energy and luminosity is discussed in the frame of a phenomenological model developed previously by the authors and now extended to include new mechanisms, able to explain and give solutions to discrepancies between model predictions and detector behaviour after hadron irradiation. Different silicon material parameters resulting from different technologies are considered to evaluate what materials are harder to radiation and consequently could minimise the degradation of device parameters in conditions of continuous long time operation. (authors)
Field Tests on Hydrodynamic and Hybrid Operation of a Bidirectional Thrust Bearing of a Pump-Turbine
Directory of Open Access Journals (Sweden)
Michał Wasilczuk
2017-12-01
Full Text Available In vertical shaft pump turbines operating in pumped storage power plants an important role is played by a thrust bearing. Due to the bidirectional character of operation, thrust bearing tilting pads have to be supported symmetrically, which is known to be unfavourable from the point of view of their performance. Large thrust bearings have to be carefully designed so as to minimise excessive thermo-elastic pad deformations. The research into fluid film thrust bearings has been quite extensive over the years, comprising theoretical studies of bearing properties with the use of more and more sophisticated calculation codes. On the other hand, the availability of experimental field data on bearing operation is limited, for obvious reasons. In this paper the authors present part of the results of extensive field tests of a large bearing of a pump-turbine they have conducted in a pumped storage power plant. Hopefully this data will be of interest to other researchers to compare theoretical predictions to measurement data.
Waggoner, Lauren B; Grant, Devon A; Van Dongen, Hans P A; Belenky, Gregory; Vila, Bryan
2012-11-01
This study assessed the utility of a combined field and laboratory research design for measuring the impact of consecutive night shift work on the sleepiness, vigilance, and driving performance of police patrol officers. For police patrol officers working their normal night shift duty cycles, simulated driving performance and psychomotor vigilance were measured in a laboratory on two separate occasions: in the morning after the last of five consecutive 10.7-h night shifts, and at the same time in the morning after three consecutive days off duty. Order of participation in conditions was randomized among subjects. Subjects experienced manipulation of sleep schedules due to working night shifts in a real operational environment, but performance testing was conducted under controlled laboratory conditions. N = 29 active-duty police patrol officers (27 male, 2 female; age 37.1 ± 6.3 years) working night shift schedules participated in this study. Simulated driving performance, psychomotor vigilance, and subjective sleepiness were significantly degraded following 5 consecutive night shifts as compared to 3 consecutive days off duty, indicating that active-duty police officers are susceptible to performance degradation as a consequence of working nights. This combined field and laboratory research design succeeded in bridging the gap between the realism of the operational environment and the control of laboratory performance testing, demonstrating that this is a useful approach for addressing the relationship between shift work induced fatigue and critical operational task performance.
Young, E. A.; Bailey, W. O. S.; Al-Mosawi, M. K.; Beduz, C.; Yang, Y.; Chappell, S.; Twin, A.
Since stand alone cryocooler systems have become more widely available, there has been increased commercial interest in superconductor applications in the temperature range intermediate to liquid helium and liquid nitrogen. There are however few facilities that have large in-field bore size with variable temperatures. A large bore system can reduce costs associated with full scale demonstration magnets by testing smaller coils and qualify medium length (up to meters) conductors. A 5 T, wide bore, (170 mm) Nb3Sn Oxford Instrument magnet has been integrated into a custom built dual mode refrigerator/helium flow cryostat with 600A HTS current leads. In one mode the system can be used with zero field without cost of liquid helium relying for cooling on a Sumitomo GM cryocooler with 1.5W at 4.2K: (no He) this can be used either as the sole characterisation method, or as a preliminary check before more expensive and extensive measurements are taken. The first measurements using MgB2 wire from 10 to 20K were made using a transient current step of ∼5s duration, as opposed to a DC measurement. This has the advantage of not requiring thermal equilibrium to be achieved at nominal current. The feasibility of this technique for determining critical transport properties is discussed.
Charging and the cross-field discharge during electron accelerator operation on a rocket
International Nuclear Information System (INIS)
Kellogg, P.J.; Monson, S.J.
1988-01-01
We present some limited results obtained from the flight of SCEX II, from Poker Flat, Alaska, on January 31, 1987. Some of the experiments were aimed at understanding neutralization processes around an electron beam emitting rocket. It was expected that electrons drifting in the strong electric fields around the charged rocket would acquire sufficient energy to ionize neutrals, and that the resulting ions would be hurled outward at energies up to the rocket potential. Three hemispherical retarding potential analyzers were ejected from the main payload to measure these ions. This experiment was successful, in spite of arcs which developed around the batteries for the electron guns, which degraded the emitted electron beam to unusable levels except for about 8 sec of the flight. Ions were observed at energies up to 175 eV, the limit of the analyzers. The main payload carried, in addition to the electron accelerator, two arms with conducting elements to act as Langmuir probes, and to measure floating potentials. These measurements show that fields sufficient to accelerate electrons to ionizing energies were present around the rocket. (author)
International Nuclear Information System (INIS)
Fritts, J.E.; McCord, J.P.
1995-02-01
The Environmental Restoration (ER) Project at Sandia National Laboratories, New Mexico is managing the project to assess and, when necessary, to remediate sites contaminated by the lab operations. Within the ER project, the site-wide hydrogeologic characterization task is responsible for the area-wide hydrogeologic investigation. The purpose of this task is to reduce the uncertainty about the rate and direction of groundwater flow beneath the area and across its boundaries. This specific report deals with the installation of PGS-1 monitoring well which provides information on the lithology and hydrology of the aquifer in the northern area of the Kirtland Air Force Base. The report provides information on the well design; surface geology; stratigraphy; structure; drilling, completion, and development techniques; and borehole geophysics information
Energy Technology Data Exchange (ETDEWEB)
Uchida, Shunsuke [Energy Research Lab., Ibaraki (Japan); Ohsumi, Katsumi; Takashima, Yoshie [Hitachi Works, Ibaraki (Japan)
1995-03-01
Improvements of operational procedures to control water chemistry, e.g., nickel/iron control, as well as application of hardware improvements for reducing radioactive corrosion products resulted in an extremely low occupational exposure of less than 0.5 man.Sv/yr without any serious impact on the radwaste system, for BWR plants involved in the Japanese Improvement and Standardization Program. Recently, {sup 60}C radioactively in the reactor water has been increasing due to less crud fixation on the two smooth surfaces of new type high performance fuels and to the pH drop caused by chromium oxide anions released from stainless steel structures and pipings. This increase must be limited by changes in water chemistry, e.g., applications of modified nickel/iron ratio control and weak alkali control. Controlled water chemistry to optimize three points, the plant radiation level and integrities of fuel and structural materials, is the primary future subject for BWR water chemistry.
Optimization of well field operation: case study of søndersø waterworks, Denmark
DEFF Research Database (Denmark)
Hansen, Annette Kirstine; Madsen, Henrik; Bauer-Gottwein, Peter
2013-01-01
An integrated hydrological well field model (WELLNES) that predicts the water level and energy consumption in the production wells of a waterworks is used to optimize the management of a waterworks with the speed of the pumps as decision variables. The two-objective optimization problem...... variable-speed pumps, it is possible to save 42% of the specific energy consumption and at the same time improve the risk objective function. The payback period of investing in new variable speed pumps is only 3.1 years, due to the large savings in electricity. The case study illustrates the efficiency...... of minimizing the risk of contamination from a nearby contaminated site and minimizing the energy consumption of the waterworks is solved by genetic algorithms. In comparison with historical values, significant improvements in both objectives can be obtained. If the existing on/off pumps are changed to new...
Some characteristics in operation of long exploited oil fields in Fergana depression. [USSR
Energy Technology Data Exchange (ETDEWEB)
Gordinskii, E V; Ovanesov, M G; Irmatov, E K
1969-01-01
A review of geological and oil production data from 3 Fergana fields is presented. The reservoirs are small, tectonically bounded, and are anticlines of Paleogenic carbonates. Reservoirs are heterogeneous with porosity ranging from 3 to 25% and permeability ranging from a few to 500 md. Some of the reservoirs have expanding gas caps, some are solution drive, and others have been waterflooded. All are now in the final stage of depletion. Production history and characteristics of each group are given. One way of increasing present production rate appears to be injection of gas or air into the reservoirs. This can be done inexpensively, since additional injection wells would not have to be drilled and some produced gas is available. Increased fluid withdrawal from present wells should also be beneficial.
International Nuclear Information System (INIS)
Burrell, K. H.; Garofalo, A. M; Osborne, T. H.; Schaffer, M. J.; Snyder, P. B.; Solomon, W. M.; Park, J.-K.; Fenstermacher, M. E.
2012-01-01
Results from recent experiments demonstrate that quiescent H-mode (QH-mode) sustained by magnetic torque from non-axisymmetric magnetic fields is a promising operating mode for future burning plasmas. Using magnetic torque from n=3 fields to replace counter-I p torque from neutral beam injection (NBI), we have achieved long duration, counter-rotating QH-mode operation with NBI torque ranging from counter-I p to up to co-I p values of 1-1.3 Nm. This co-I p torque is 3 to 4 times the scaled torque that ITER will have. These experiments utilized an ITER-relevant lower single-null plasma shape and were done with ITER-relevant values of ν ped * and β N ped . These discharges exhibited confinement quality H 98y2 =1.3, in the range required for ITER. In preliminary experiments using n=3 fields only from a coil outside the toroidal coil, QH-mode plasmas with low q 95 =3.4 have reached fusion gain values of G=β N H 89 /q 95 2 =0.4, which is the desired value for ITER. Shots with the same coil configuration also operated with net zero NBI torque. The limits on G and co-I p torque have not yet been established for this coil configuration. QH-mode work to has made significant contact with theory. The importance of edge rotational shear is consistent with peeling-ballooning mode theory. Qualitative and quantitative agreements with the predicted neoclassical toroidal viscosity torque is seen.
Williams, P Stephen
2016-05-01
Asymmetrical flow field-flow fractionation (As-FlFFF) has become the most commonly used of the field-flow fractionation techniques. However, because of the interdependence of the channel flow and the cross flow through the accumulation wall, it is the most difficult of the techniques to optimize, particularly for programmed cross flow operation. For the analysis of polydisperse samples, the optimization should ideally be guided by the predicted fractionating power. Many experimentalists, however, neglect fractionating power and rely on light scattering detection simply to confirm apparent selectivity across the breadth of the eluted peak. The size information returned by the light scattering software is assumed to dispense with any reliance on theory to predict retention, and any departure of theoretical predictions from experimental observations is therefore considered of no importance. Separation depends on efficiency as well as selectivity, however, and efficiency can be a strong function of retention. The fractionation of a polydisperse sample by field-flow fractionation never provides a perfectly separated series of monodisperse fractions at the channel outlet. The outlet stream has some residual polydispersity, and it will be shown in this manuscript that the residual polydispersity is inversely related to the fractionating power. Due to the strong dependence of light scattering intensity and its angular distribution on the size of the scattering species, the outlet polydispersity must be minimized if reliable size data are to be obtained from the light scattering detector signal. It is shown that light scattering detection should be used with careful control of fractionating power to obtain optimized analysis of polydisperse samples. Part I is concerned with isocratic operation of As-FlFFF, and part II with programmed operation.
International Nuclear Information System (INIS)
Kneipp, Marco A.C.
1999-10-01
Soliton time delays and the semiclassical limit for soliton S-matrices are calculated for non-simply laced Affine Toda Field Theories. The phase shift is written as a sum over bilinears on the soliton conserved charges. The results apply to any two solitons of any Affine Toda Field Theory. As a by-product, a general expression for the number of bound states and the values of the coupling in which the S-matrix can be diagonal are obtained. In order to arrive at these results, a vertex operator is constructed, in the principal gradation, for non-simply laced affine Lie algebras, extending the previous constructions for simply laced and twisted affine Lie algebras. (author)
Energy Technology Data Exchange (ETDEWEB)
Liu, Ning [The Boeing Company, Canoga Park, CA (United States); Rutherford, Phil [The Boeing Company, Canoga Park, CA (United States); Amar, Ravnesh [The Boeing Company, Canoga Park, CA (United States)
2010-09-01
This Annual Site Environmental Report (ASER) for 2009 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2009 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.
Energy Technology Data Exchange (ETDEWEB)
Liu, Ning [The Boeing Company, Canoga Park, CA (United States); Rutherford, Phil [The Boeing Company, Canoga Park, CA (United States); Amar, Ravnesh [The Boeing Company, Canoga Park, CA (United States)
2011-09-01
This Annual Site Environmental Report (ASER) for 2010 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2010 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.
International Nuclear Information System (INIS)
Le Blanc, Katya; Oxstrand, J.H.; Waicosky, T.
2012-01-01
Although computer-based procedures (CBPs) have been investigated as a way to enhance operator performance on procedural tasks in the nuclear industry for almost thirty years, they are not currently widely deployed at United States utilities. One of the barriers to the wide scale deployment of CBPs is the lack of operational experience with CBPs that could serve as a sound basis for justifying the use of CBPs for nuclear utilities. Utilities are hesitant to adopt CBPs because of concern over potential costs of implementation, and concern over regulatory approval. Regulators require a sound technical basis for the use of any procedure at the utilities; without operating experience to support the use CBPs, it is difficult to establish such a technical basis. In an effort to begin the process of developing a technical basis for CBPs, researchers at Idaho National Laboratory are partnering with industry to explore CBPs with the objective of defining requirements for CBPs and developing an industry-wide vision and path forward for the use of CBPs. This paper describes the results from a qualitative study aimed at defining requirements for CBPs to be used by field operators and maintenance technicians. (author)
Energy Technology Data Exchange (ETDEWEB)
Rogers, W.R.; Coelho, A.M. Jr.; Easley, S.P.; Orr, J.L.; Smith, H.D.; Taylor, L.L.; Tuttle, M.L.
1987-01-01
The objective of this program is to investigate, using the baboon as a nonhuman primate surrogate for the human, possible hehavioral effects associated with exposure to high intensity 60 Hz electric fields. Results from this program, along with information from experiments conducted elsewhere, will be used by the Department of Energy (DOE) to estimate and evaluate the likelihood of deleterious consequences resulting from exposure of humans to the electric fields associated with power transmission over high voltage lines. This research program consists of four major research projects, all of which have been successfully completed. The third project assessed, in separate experiments conducted at 30 and 60 kV/m, effects of chronic exposure to electric fields on the performance of two operant conditioning tasks, fixed ratio (FR), and differential reinforcement of low rate (DRL). In the same two experiments, the fourth project investigated, using the systematic quantitative observational sampling methods of primatology, the possible stress-inducing effects of chronic exposure to 60 Hz electric fields on the behavior of baboons living in small social groups. This volume contains only appendices for projects 3 and 4. 81 figs., 67 tabs.
International Nuclear Information System (INIS)
Szymanska, K.; Achenbach, P.; Agnello, M.; Botta, E.; Bracco, A.; Bressani, T.; Camera, F.; Cederwall, B.; Feliciello, A.; Ferro, F.; Gerl, J.; Iazzi, F.; Kavatsyuk, M.; Kojouharov, I.; Pochodzalla, J.; Raciti, G.; Saito, T.R.; Sanchez Lorente, A.; Tegner, P.-E.; Wieland, O.
2008-01-01
The use of High Purity Germanium detectors (HPGe) has been planned in some future experiments of hadronic physics. The crystals will be located close to large spectrometers where the magnetic fringing field will not be negligible and their performances might change. Moreover high precision is required in these experiments. The contribution of magnetic field presence and long term measurements is unique. In this paper the results of systematic measurements of the resolution, stability and efficiency of a crystal operating inside a magnetic field of 0.8 T, using radioactive sources in the energy range from 0.08 to 1.33 MeV, are reported. The measurements have been repeated during several months in order to test if any permanent damage occurred. The resolution at 1.117 and 1.332 MeV gamma-rays from a 60 Co source has been measured at different magnetic fields in the range of 0-0.8 T and the results are compared with the previous data
Martínez-Búrdalo, M; Martín, A; Sanchis, A; Villar, R
2009-02-01
In this work, the numerical dosimetry in human exposure to the electromagnetic fields from antennas of wireless devices, such as those of wireless local area networks (WLAN) access points or phone and computer peripherals with Bluetooth antennas, is analyzed with the objective of assessing guidelines compliance. Several geometrical configurations are considered to simulate possible exposure situations of a person to the fields from WLAN or Bluetooth antennas operating at 2400 MHz. The exposure to radiation from two sources of different frequencies when using a 1800 MHz GSM mobile phone connected via Bluetooth with a hands-free car kit is also considered. The finite-difference time-domain (FDTD) method is used to calculate electric and magnetic field values in the vicinity of the antennas and specific absorption rates (SAR) in a high-resolution model of the human head and torso, to be compared with the limits from the guidelines (reference levels and basic restrictions, respectively). Results show that the exposure levels in worst-case situations studied are lower than those obtained when analyzing the exposure to mobile phones, as could be expected because of the low power of the signals and the distance between the human and the antennas, with both field and SAR values being far below the limits established by the guidelines, even when considering the combined exposure to both a GSM and a Bluetooth antenna. Copyright 2008 Wiley-Liss, Inc.
Trogisch, S.; Hoffmann, J.; Daza Bertrand, L.
In the past years research in the molten carbonate fuel cells (MCFC) area has been focusing its efforts on the utilisation of natural gas as fuel (S. Geitmann, Wasserstoff- & Brennstoffzellen-Projekte, 2002, ISBN 3-8311-3280-1). In order to increase the advantages of this technology, an international consortium has worked on the utilisation of biogas as fuel in MCFC. During the 4 years lasting RTD project EFFECTIVE two different gas upgrading systems have been developed and constructed together with two mobile MCFC test beds which were operated at different locations for approximately 2.000-5.000 h in each run with biogas from different origins and quality. The large variety of test locations has enabled to gather a large database for assessing the effect of the different biogas qualities on the complete system consisting of the upgrading and the fuel cell systems. The findings are challenging. This article also aims at giving an overview of the advantages of using biogas as fuel for fuel cells.
VAS operational procedures and results at the Kansas City Satellite Field Services Station
Heckman, B.; Carle, W.; Anthony, R.
1983-01-01
An operational assessment of VAS data by using a Man-computer Interactive Data Access System (McIDAS) terminal linked by a 9600 band telephone line is discussed. Seven hours of VAS data were processed and edited daily. Data was scheduled 16 hours a day, 7 days a week; however, during this time period there were very few days with 16 hours of data to evalute. The McIDAS terminal, which has 10 display frames and 5 graphics, provide access to the sounding data processed. These data are processed using two procedures. The dwell sounding data are generated by using all 12 spectral channels with a spin budget of 39. To provide coverage for most of the United States, soundings are made starting at 18 minutes after the hour from approximately 49 deg N to 36 deg N and at 48 minutes after the hour from 36 deg N to 26 deg N. The dwell imaging mode uses 11 channels but the spin budge is 17. With the reduced spin budget, retrievals can be made at 18 or 48 minutes after the hour for approximately 44 deg N to 27 deg N. With these constraints a schedule, of data sets was proposed to use the schedule and how the data set could be used are shown.
Quantum field theory. From operators to path integrals. 2. rev. and enl. ed.
Energy Technology Data Exchange (ETDEWEB)
Huang, Kerson
2010-07-01
A new, updated and enhanced edition of the classic work, which was welcomed for its general approach and self-sustaining organization of the chapters. Written by a highly respected textbook writer and researcher, this book has a more general scope and adopts a more practical approach than other books. It includes applications of condensed matter physics, first developing traditional concepts, including Feynman graphs, before moving on to such key topics as functional integrals, statistical mechanics and Wilson's renormalization group. The author takes care to explain the connection between the latter and conventional perturbative renormalization. Due to the rapid advance and increase in importance of low dimensional systems, this second edition fills a gap in the market with its added discussions of low dimensional systems, including one-dimensional conductors. All the chapters have been revised, while more clarifying explanations and problems have been added. A noteworthy new topic is Polchinski's renormalization equation, which is derived, and then solved to obtain the Halpern-Huang asymptotically free scalar field. The latter has found application in the dark-energy problem in cosmology. (orig.)
Quantum field theory. From operators to path integrals. 2. rev. and enl. ed.
International Nuclear Information System (INIS)
Huang, Kerson
2010-01-01
A new, updated and enhanced edition of the classic work, which was welcomed for its general approach and self-sustaining organization of the chapters. Written by a highly respected textbook writer and researcher, this book has a more general scope and adopts a more practical approach than other books. It includes applications of condensed matter physics, first developing traditional concepts, including Feynman graphs, before moving on to such key topics as functional integrals, statistical mechanics and Wilson's renormalization group. The author takes care to explain the connection between the latter and conventional perturbative renormalization. Due to the rapid advance and increase in importance of low dimensional systems, this second edition fills a gap in the market with its added discussions of low dimensional systems, including one-dimensional conductors. All the chapters have been revised, while more clarifying explanations and problems have been added. A noteworthy new topic is Polchinski's renormalization equation, which is derived, and then solved to obtain the Halpern-Huang asymptotically free scalar field. The latter has found application in the dark-energy problem in cosmology. (orig.)
Effective use of complex secondary recovery methods in operation of small oil fields
Energy Technology Data Exchange (ETDEWEB)
Ibragimov, M R; Akulov, V P; Khutorov, A M
1966-11-01
The North Sokhs Field, located in the southern part of the Fergen depression, is composed of many horizons and has an anticlinal structure. The eighth horizon has highest oil saturation, with an average porosity of 17% and permeability of 80 md. Poor oil recovery was initially obtained from this horizon because the basic producing mechanism was solution gas drive. In 1961, when reservoir pressure was 94 kg/cmU2D and gas factor was 700-800mU3D/ton, pressure maintenance was initiated by injection of gas to the structure. Gas injection improved oil recovery considerably; however, high gas-oil ratios appeared in several wells. Next, peripheral water injection was started, and continued simultaneously with gas injection. The simultaneous injection of gas and water almost doubled oil production. Because of continued, high produced gas/oil ratios, gas injection was eventually discontinued, while water injection was continued. Water injection is building up reservoir pressure and improving oil recovery.
International research co-operation in the field of controlled thermonuclear fusion
International Nuclear Information System (INIS)
2004-01-01
This 26th report by the Swiss Federal Office for Education and Science presents a review of work done in Swiss institutes in 2003 as part of international research into thermonuclear fusion. A broad outline of the project and of its significance within the wider field of thermonuclear fusion research is given. This is followed by a review of the significant events in the world of fusion research, with emphasis placed on ITER and on the EURATOM fusion programme. A further chapter summarises events in Switzerland in 2003 and the report closes with a list of contacts for more information. Three annexes provide information on the current situation in fusion research, as well as scientific and technical highlights of the work performed in 2003 at the Plasma Physics Research Centre CRPP at the Federal Institute of Technology EPFL in Lausanne, Switzerland. Annex 3 reports on results obtained at the Physics Institute of the University of Basle. The annexes are for the benefit of the technically and scientifically versed reader, and brief summaries of them are given in the main body of the report
Absolute continuity for operator valued completely positive maps on C∗-algebras
Gheondea, Aurelian; Kavruk, Ali Şamil
2009-02-01
Motivated by applicability to quantum operations, quantum information, and quantum probability, we investigate the notion of absolute continuity for operator valued completely positive maps on C∗-algebras, previously introduced by Parthasarathy [in Athens Conference on Applied Probability and Time Series Analysis I (Springer-Verlag, Berlin, 1996), pp. 34-54]. We obtain an intrinsic definition of absolute continuity, we show that the Lebesgue decomposition defined by Parthasarathy is the maximal one among all other Lebesgue-type decompositions and that this maximal Lebesgue decomposition does not depend on the jointly dominating completely positive map, we obtain more flexible formulas for calculating the maximal Lebesgue decomposition, and we point out the nonuniqueness of the Lebesgue decomposition as well as a sufficient condition for uniqueness. In addition, we consider Radon-Nikodym derivatives for absolutely continuous completely positive maps that, in general, are unbounded positive self-adjoint operators affiliated to a certain von Neumann algebra, and we obtain a spectral approximation by bounded Radon-Nikodym derivatives. An application to the existence of the infimum of two completely positive maps is indicated, and formulas in terms of Choi's matrices for the Lebesgue decomposition of completely positive maps in matrix algebras are obtained.
Use of radiation maps in a virtual training environment for NPP field operators
Energy Technology Data Exchange (ETDEWEB)
Nystad, Espen; Droeivoldsmo, Asgeir; Sebok, Angelia
2002-08-15
Virtual reality (VR) provides a useful tool for training because it offers the student direct experience with the material to be learned. In the nuclear industry, VR provides a safe method of training workers on tasks to be performed in radiation-exposed areas. VR training may be used for planning operations so they can be performed quickly and efficiently, thus reducing worker radiation doses. This study evaluated three types of radiation distribution training for the Halden Boiling Water Reactor (HBWR) hall. Two training types were presented using VR models and computerized radiation maps; the third type of training used a paper map showing the reactor hall and the radiation distribution. Participants were instructed to learn the radiation layout and practice walking along a route in the reactor hall. They were also instructed to learn to identify the location of points that they would later measure. Following training, participants in the three training groups participated in the same experimental session. During the experimental session, participants applied the skills they had acquired in training by walking through the reactor hall and performing the measuring tasks they had learned about in the training session. The VR training included a guided condition, where users were shown the path they would need to learn, and a non-guided condition, where users were relatively free to explore. These two conditions provided active (non-guided) and passive (guided) training conditions. A number of performance measures were collected, including radiation awareness, presence, usability, and objective performance measures. Participants in the VR non-guided (active learning) condition demonstrated higher radiation awareness, reported higher transfer of training, and recognized more measure points than subjects in the VR guided (passive learning) and/or map conditions. The results of this study indicate that VR can provide a useful medium for training spatial skills. The
Directory of Open Access Journals (Sweden)
Brad J. Arnold
2014-07-01
Full Text Available Surface irrigation, such as flood or furrow, is the predominant form of irrigation in California for agronomic crops. Compared to other irrigation methods, however, it is inefficient in terms of water use; large quantities of water, instead of being used for crop production, are lost to excess deep percolation and tail runoff. In surface-irrigated fields, irrigators commonly cut off the inflow of water when the water advance reaches a familiar or convenient location downfield, but this experience-based strategy has not been very successful in reducing the tail runoff water. Our study compared conventional cutoff practices to a retroactively applied model-based cutoff method in four commercially producing alfalfa fields in Northern California, and evaluated the model using a simple sensor system for practical application in typical alfalfa fields. These field tests illustrated that the model can be used to reduce tail runoff in typical surface-irrigated fields, and using it with a wireless sensor system saves time and labor as well as water.
Energy Technology Data Exchange (ETDEWEB)
None
2014-06-30
This Annual Site Environmental Report (ASER) for 2013 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of the Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, operation and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward environmental restoration and decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2013 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling. Due to the suspension of D&D activities in Area IV, no effluents were released into the atmosphere during 2013. Therefore, the potential radiation dose to the general public through airborne release was zero. Similarly, the radiation dose to an offsite member of the public (maximally exposed individual) due to direct radiation from SSFL is indistinguishable from background. All radioactive wastes are processed for disposal at DOE disposal sites and/or other licensed sites approved by DOE for radioactive waste
International Nuclear Information System (INIS)
Santilli, R.M.
1977-01-01
In this paper we first study the equivalence transformations of class C 2 , regular, tensorial, quasi-linear systems of field which (a) preserve the continuity, regularity, and quasi-linear structure of the systems; and (b) occur within a fixed system of Minkowski coordinates and field components. We identify, among the transformations of this class, those which either induce or preserve a self-adjoint structure of the field equations and we term them genotopic and isotopic transformations, respectively. We then give the necessary and sufficient conditions for an equivalence transformation of the above type to be either genotopic or isotopic. By using this methodology, we then extend the theorem on the necessary and sufficient condition for the existence of ordered direct analytic representations introduced in the preceding paper to the case of ordered indirect analytic representations in terms of the conventional Lagrange equations; we introduce a method for the construction of a Lagrangian, when it exists, in this broader context; and we explore some implications of the underlying methodology for the problem of the structure of the Lagrangian capable of representing interactions within the framework of the indirect analytic representations. Some of the several aspects which demand an inspection prior to the use of this analytic approach in actual models are pointed out.In particular, we indicate a possible deep impact in the symmetries and conservation laws of the system generated by the use of the concept of indirect analytic representation
Directory of Open Access Journals (Sweden)
Phil Diamond
2003-01-01
Full Text Available Sensitivity of output of a linear operator to its input can be quantified in various ways. In Control Theory, the input is usually interpreted as disturbance and the output is to be minimized in some sense. In stochastic worst-case design settings, the disturbance is considered random with imprecisely known probability distribution. The prior set of probability measures can be chosen so as to quantify how far the disturbance deviates from the white-noise hypothesis of Linear Quadratic Gaussian control. Such deviation can be measured by the minimal Kullback-Leibler informational divergence from the Gaussian distributions with zero mean and scalar covariance matrices. The resulting anisotropy functional is defined for finite power random vectors. Originally, anisotropy was introduced for directionally generic random vectors as the relative entropy of the normalized vector with respect to the uniform distribution on the unit sphere. The associated a-anisotropic norm of a matrix is then its maximum root mean square or average energy gain with respect to finite power or directionally generic inputs whose anisotropy is bounded above by a≥0. We give a systematic comparison of the anisotropy functionals and the associated norms. These are considered for unboundedly growing fragments of homogeneous Gaussian random fields on multidimensional integer lattice to yield mean anisotropy. Correspondingly, the anisotropic norms of finite matrices are extended to bounded linear translation invariant operators over such fields.
Energy Technology Data Exchange (ETDEWEB)
Hwang, C. [Miami Univ., Oxford, OH (United States). Dept. of Microbiology; Wu, W.M. [Stanford Univ., CA (United States). Dept. of Civil and Environmental Engineering; Gentry, T.J. [Oak Ridge National Lab., TN (US). Environmental Sciences Div.] (and others)
2006-08-15
High levels of nitrate are present in groundwater migrating from the former waste disposal ponds at the Y-12 National Security Complex in Oak Ridge, TN. A field-scale denitrifying fluidized bed reactor (FBR) was designed, constructed, and operated with ethanol as an electron donor for the removal of nitrate. After inoculation, biofilms developed on the granular activated carbon particles. Changes in the bacterial community of the FBR were evaluated with clone libraries (n=500 partial sequences) of the small-subunit rRNA gene for samples taken over a 4-month start-up period. Early phases of start-up operation were characterized by a period of selection, followed by low diversity and predominance by Azoarcus-like sequences. Possible explanations were high pH and nutrient limitations. After amelioration of these conditions, diversification increased rapidly, with the appearance of Dechloromonas, Pseudomonas, and Hydrogenophaga sequences. Changes in NO{sub 3}, SO{sub 4}, and pH also likely contributed to shifts in community composition. The detection of sulfate-reducing-bacteria-like sequences closely related to Desulfovibrio and Desulfuromonas in the FBR have important implications for downstream applications at the field site. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Michael D. Durham
2003-05-01
With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Mercury is known to have toxic effects on the nervous system of humans and wildlife. Although it exists only in trace amounts in coal, mercury is released when coal burns and can accumulate on land and in water. In water, bacteria transform the metal into methylmercury, the most hazardous form of the metal. Methylmercury can collect in fish and marine mammals in concentrations hundreds of thousands times higher than the levels in surrounding waters. One of the goals of DOE is to develop technologies by 2005 that will be capable of cutting mercury emissions 50 to 70 percent at well under one-half of today's costs. ADA Environmental Solutions (ADA-ES) is managing a project to test mercury control technologies at full scale at four different power plants from 2000--2003. The ADA-ES project is focused on those power plants that are not equipped with wet flue gas desulfurization systems. ADA-ES has developed a portable system that will be tested at four different utility power plants. Each of the plants is equipped with either electrostatic precipitators or fabric filters to remove solid particles from the plant's flue gas. ADA-ES's technology will inject a dry sorbent, such as activated carbon, which removes the mercury and makes it more susceptible to capture by the particulate control devices. A fine water mist may be sprayed into the flue gas to cool its temperature to the range where the dry sorbent is most effective. PG&E National Energy Group is providing two test sites that fire bituminous coals and both are equipped with electrostatic precipitators and carbon/ash separation systems. Wisconsin Electric Power Company is providing a third test site that burns Powder River Basin (PRB) coal and
Fundamental investigation of high temperature operation of field effect transistor devices
Chern, Jehn-Huar
, JFET, pseudomorphic-HEMT, and modulation doped FET (MODFET) devices for high-temperature applications were investigated and addressed in terms of device performance such as transconductance, leakage current density, and current gain. Wide gap materials such as GaN have low carrier generation rate at high temperatures and, hence, high operation temperature capabilities and potential.
Energy Technology Data Exchange (ETDEWEB)
Kumar, S.; Dhar, A., E-mail: adhar@phy.iitkgp.ernet.in
2015-10-15
Highlights: • Alternative to chemically crosslinking of PMMA to achieve low leakage in provided. • Effect of LiF in reducing gate leakage through the OFET device is studied. • Effect of gate leakage on transistor performance has been investigated. • Low voltage operable and low temperature processed n-channel OFETs were fabricated. - Abstract: We report low temperature processed, low voltage operable n-channel organic field effect transistors (OFETs) using N,N′-Dioctyl-3,4,9,10-perylenedicarboximide (PTCDI-C{sub 8}) organic semiconductor and poly(methylmethacrylate) (PMMA)/lithium fluoride (LiF) bilayer gate dielectric. We have studied the role of LiF buffer dielectric in effectively reducing the gate leakage through the device and thus obtaining superior performance in contrast to the single layer PMMA dielectric devices. The bilayer OFET devices had a low threshold voltage (V{sub t}) of the order of 5.3 V. The typical values of saturation electron mobility (μ{sub s}), on/off ratio and inverse sub-threshold slope (S) for the range of devices made were estimated to be 2.8 × 10{sup −3} cm{sup 2}/V s, 385, and 3.8 V/decade respectively. Our work thus provides a potential substitution for much complicated process of chemically crosslinking PMMA to achieve low leakage, high capacitance, and thus low operating voltage OFETs.
Energy Technology Data Exchange (ETDEWEB)
Worsey, P.N.; Canon, C.
1988-06-01
Full scale and field testing of a simple mechanical stemming aid is described. The aid comprises a solid unit placed in the stemming above the explosive column and is designed to improve blasting efficiency and reduce drilling and blasting costs. It is designed to work with back filled drill cuttings or any other suitable stemming material. The results of Phase I testing were highly successful, indicating that the stemming aid has technically an extremely good chance of success at full scale when constructed of low cost materials. Phase II of the stemming aid research and development program comprised of the testing of various forms of the stemming is at full scale in non-research oriented i.e. field settings. The stemming aid was field tested at 4 different sites for a variety of mining application: First in underground workings at the UMR experimental mine in one and three quarter inch diameter horizontal blast holes incorporated into full blast patterns; three and three and a half inch blast holes at two crushed rock/limestone quarries in the Rolla area and at a surface coal mine operation run by Peabody Coal Company at Lynnville, Indiana in which nine and seven eighths, ten and five eighths and fifteen and a quarter inch diameter blast holes were used for parting and overburden removal. 2 refs., 37 figs., 11 tabs.
The quantisation and measurement of momentum observables
International Nuclear Information System (INIS)
Wan, K.K.; McFarlane, K.
1980-01-01
Mackey's scheme for the quantisation of classical momenta generating complete vector fields (complete momenta) is introduced, the differential operators corresponding to these momenta are introduced and discussed, and an isomorphism is shown to exist between the subclass of first-order self-adjoint differential operators, whose symmetric restrictions are essentially self-adjoint, and the complete classical momenta. Difficulties in the quantisation of incomplete momenta are discussed, and a critique given. Finally, in an attempt to relate the concept of completeness to measurability concepts of classical and quantum global measurability are introduced, and shown to require completeness. These results afford strong physical insight into the nature of complete momenta, and leads us to suggest a quantisability condition based upon global measurability. (author)
1999-03-01
The Mobile Surveillance and Wireless Communication Systems Field Operational Test (FOT) evaluated the performance of wireless traffic detection and communications systems in areas where permanent detectors, electrical power, and landline communicatio...
International Nuclear Information System (INIS)
Alvarez R, J. T.
2014-10-01
In this work is presented in a didactic way the operative magnitudes system ICRU, showing as these magnitudes carry out an appropriate estimate of the effective equivalent doses H E and the effective dose. The objective is to present the basic concepts of the dosimetry for radiation external fields with purposes of radiological protection, because the assimilation lack and technological development of this dosimetric magnitudes system has persisted for near 50 years, in terms of practice of the radiological protection in Mexico. Also, this system is an essential part of safety basic standards of the IAEA and ICRP recommendations 26, 60, 74 and 103, as well as of the ICRU 25, 39, 43, 51 and 57. (Author)
Assmann, Ralph Wolfgang; Brugger, Markus; Efthymiopoulos, Ilias; Feldbaumer, Eduard; Garrido, Mar Capeans; Glaser, Maurice; Kramer, Daniel; Linssen, Lucie; Losito, Roberto; Moll, Michael; Rembser, Christoph; Silari, Marco; Thurel, Yves; Tsesmelis, Emmanuel; Vincke, Helmut; CERN. Geneva. The LHC experiments Committee; LHCC
2010-01-01
In the present proposal we present the need for improved proton and mixed-field irradiation facilities with slow beam extraction at CERN. Strong needs are expressed by both the detector and accelerator communities and concern the LHC operation era as well as the upgrades of machine and experiments. The current facilities and test areas have a number of limitations and drawbacks. Preliminary studies indicate that there are possibilities for a coherent and cost-effective approach towards improved facilities for the future. The aim of this document is to inform the LHCC and seek its recognition for the need of such facilities. In addition we would appreciate the support of the LHCC for pursuing further implementation studies at a PS East Hall location.
Field Sampling Plan for the Operable Units 6-05 and 10-04 Remedial Action, Phase IV
Energy Technology Data Exchange (ETDEWEB)
R. Wells
2006-11-14
This Field Sampling Plan outlines the collection and analysis of samples in support of Phase IV of the Waste Area Group 10, Operable Units 6-05 and 10-04 remedial action. Phase IV addresses the remedial actions to areas with the potential for unexploded ordnance at the Idaho National Laboratory Site. These areas include portions of the Naval Proving Ground, the Arco High-Altitude Bombing Range, and the Twin Buttes Bombing Range. The remedial action consists of removal and disposal of ordnance by high-order detonation, followed by sampling to determine the extent, if any, of soil that might have been contaminated by the detonation activities associated with the disposal of ordnance during the Phase IV activities and explosives during the Phase II activities.
Energy Technology Data Exchange (ETDEWEB)
Sa, Andrea Nicolino de; Silva, Dayana Nunes e; Calderon, Agostinho [Petroleo Brasileiro S.A. (PETROBRAS), Rio de janeiro, RJ (Brazil)
2012-07-01
The need to reduce oil extraction costs by increasing the recovery factor in mature fields unconsolidated sandstone reservoirs motivated the development of drilling and completion techniques that integrate the various interfaces of engineering the well, resulting in a final well configuration that provides maximum oil production at a lower cost. Due to the continued growth of drilling and completion of new wells or deviation of old wells in the design of mesh density field with an advanced degree of exploitation, PETROBRAS took the challenge to seek options for projects well, in order to maintain productivity and reduce their construction time, with the optimization of drilling and sand control systems. To achieve these goals, PETROBRAS developed the SCARS - Simultaneous Sand Control and Liner Cementing System, a pioneer technique in the global oil industry, which consists of a one trip sequence of operations in which sand control screens and liner are installed followed by the open hole gravel pack operation performed with the alpha and beta waves deposition technique, using a non aqueous system as a carrier fluid. The sequence is completed by liner cementing in the same trip. The great success of this project was based on the definition of a specific application scenario and demands allowing optimization of the system. This project started with the development of a non aqueous system as a gravel pack carrier fluid in order to perform an open hole gravel pack with the alpha/beta wave deposition technique along with the development and optimization of SCARS procedures. This article details the planning and execution phases of this project and also presents a broad description of the technical aspects. (author)
Construction of some quantum stochastic operator cocycles by the ...
Indian Academy of Sciences (India)
L is closed, densely defined and symmetric, but not self-adjoint. In view of .... component of F leaves D invariant both facilitate the verification of (1.10). ... the Kolmogorov equations in the classical theory of Markov processes — see [MoP] for.
Bell, Ernest R.; Badillo, Victor; Coan, David; Johnson, Kieth; Ney, Zane; Rosenbaum, Megan; Smart, Tifanie; Stone, Jeffry; Stueber, Ronald; Welsh, Daren; Guirgis, Peggy; Looper, Chris; McDaniel, Randall
2013-10-01
The NASA Desert Research and Technology Studies (Desert RATS) is an annual field test of advanced concepts, prototype hardware, and potential modes of operation to be used on human planetary surface space exploration missions. For the 2009 and 2010 NASA Desert RATS field tests, various engineering concepts and operational exercises were incorporated into mission timelines with the focus of the majority of daily operations being on simulated lunar geological field operations and executed in a manner similar to current Space Shuttle and International Space Station missions. The field test for 2009 involved a two week lunar exploration simulation utilizing a two-man rover. The 2010 Desert RATS field test took this two week simulation further by incorporating a second two-man rover working in tandem with the 2009 rover, as well as including docked operations with a Pressurized Excursion Module (PEM). Personnel for the field test included the crew, a mission management team, engineering teams, a science team, and the mission operations team. The mission operations team served as the core of the Desert RATS mission control team and included certified NASA Mission Operations Directorate (MOD) flight controllers, former flight controllers, and astronaut personnel. The backgrounds of the flight controllers were in the areas of Extravehicular Activity (EVA), onboard mechanical systems and maintenance, robotics, timeline planning (OpsPlan), and spacecraft communicator (Capcom). With the simulated EVA operations, mechanized operations (the rover), and expectations of replanning, these flight control disciplines were especially well suited for the execution of the 2009 and 2010 Desert RATS field tests. The inclusion of an operations team has provided the added benefit of giving NASA mission operations flight control personnel the opportunity to begin examining operational mission control techniques, team compositions, and mission scenarios. This also gave the mission operations
Goossens, Dirk; Nolet, Corjan; Etyemezian, Vicken; Duarte-Campos, Leonardo; Bakker, Gerben; Riksen, Michel
2018-06-01
Five types of sediment samplers designed to measure aeolian sand transport were tested during a wind erosion event on the Sand Motor, an area on the west coast of the Netherlands prone to severe wind erosion. Each of the samplers operates on a different principle. The MWAC (Modified Wilson And Cooke) is a passive segmented trap. The modified Leatherman sampler is a passive vertically integrating trap. The Saltiphone is an acoustic sampler that registers grain impacts on a microphone. The Wenglor sampler is an optical sensor that detects particles as they pass through a laser beam. The SANTRI (Standalone AeoliaN Transport Real-time Instrument) detects particles travelling through an infrared beam, but in different channels each associated with a particular grain size spectrum. A procedure is presented to transform the data output, which is different for each sampler, to a common standard so that the samplers can be objectively compared and their relative efficiency calculated. Results show that the efficiency of the samplers is comparable despite the differences in operating principle and the instrumental and environmental uncertainties associated to working with particle samplers in field conditions. The ability of the samplers to register the temporal evolution of a wind erosion event is investigated. The strengths and weaknesses of the samplers are discussed. Some problems inherent to optical sensors are looked at in more detail. Finally, suggestions are made for further improvement of the samplers.
Stephens, G. K.; Sitnov, M. I.; Ukhorskiy, A. Y.; Vandegriff, J. D.; Tsyganenko, N. A.
2010-12-01
The dramatic increase of the geomagnetic field data volume available due to many recent missions, including GOES, Polar, Geotail, Cluster, and THEMIS, required at some point the appropriate qualitative transition in the empirical modeling tools. Classical empirical models, such as T96 and T02, used few custom-tailored modules to represent major magnetospheric current systems and simple data binning or loading-unloading inputs for their fitting with data and the subsequent applications. They have been replaced by more systematic expansions of the equatorial and field-aligned current contributions as well as by the advanced data-mining algorithms searching for events with the global activity parameters, such as the Sym-H index, similar to those at the time of interest, as is done in the model TS07D (Tsyganenko and Sitnov, 2007; Sitnov et al., 2008). The necessity to mine and fit data dynamically, with the individual subset of the database being used to reproduce the geomagnetic field pattern at every new moment in time, requires the corresponding transition in the use of the new empirical geomagnetic field models. It becomes more similar to runs-on-request offered by the Community Coordinated Modeling Center for many first principles MHD and kinetic codes. To provide this mode of operation for the TS07D model a new web-based modeling tool has been created and tested at the JHU/APL (http://geomag_field.jhuapl.edu/model/), and we discuss the first results of its performance testing and validation, including in-sample and out-of-sample modeling of a number of CME- and CIR-driven magnetic storms. We also report on the first tests of the forecasting version of the TS07D model, where the magnetospheric part of the macro-parameters involved in the data-binning process (Sym-H index and its trend parameter) are replaced by their solar wind-based analogs obtained using the Burton-McPherron-Russell approach.
International Nuclear Information System (INIS)
Grinberg, H.
1983-11-01
The projection operator method of Zwanzig and Feshbach is used to construct the time-dependent field operators in the interaction picture. The formula developed to describe the time dependence involves time-ordered cosine and sine projected evolution (memory) superoperators, from which a master equation for the interaction-picture single-particle Green's function in a Liouville space is derived. (author)
International Nuclear Information System (INIS)
Du, Hailong; Sang, Chaofeng; Wang, Liang; Bonnin, Xavier; Sun, Jizhong; Wang, Dezhen
2016-01-01
Highlights: • The in-out divertor asymmetry is studied using SOLPS. • The discharge operation and the magnetic filed have a great influence on the divertor asymmetry. • The asymmetry is not obvious in low recycling regime as that in high recycling regime. - Abstract: This paper aims to investigate the reason why the divertor in-out asymmetry was not obvious as experimentally observed in EAST only considering the classical drifts from previous simulations (Guo et al., J. Nucl. Mater. 438 (2013) 280; Du et al., J. Nucl. Mater. 463 (2015) 485). With consideration of the classical drifts, a series of different typical discharge scenarios in EAST in different magnetic field geometries were simulated by using the SOLPS5.2 code package. The simulated results reveal that the classical drifts make a major contribution to the in-out divertor asymmetry in the high recycling regime (HRR) and partial detachment (one divertor target begins to detach, while the other divertor remains attached) regime. In comparison, in low recycling regime the classical drifts play a much smaller role in the contributions to the in-out divertor asymmetry, which can explain reasonably the reason for it in Guo et al. (J. Nucl. Mater. 438 (2013) 280). In addition, the magnetic field geometry also has a great impact on the classical drifts inducing the asymmetry; it is found that for lower single-null, upper single-null and connected double-null topologies, in HRR the classical drifts play an dominant role in the contribution to the in-out divertor asymmetry, while for a disconnected double null magnetic field configuration, they play a minor role, which is the reason why the in-out asymmetry was unobvious by considering the drifts in Du et al. (J. Nucl. Mater. 463 (2015) 485).
Energy Technology Data Exchange (ETDEWEB)
Du, Hailong; Sang, Chaofeng [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Wang, Liang [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China); Bonnin, Xavier [LSPM-CNRS, Université Paris 13, Sorbonne Paris Cité, F-93430 Villetaneuse (France); Sun, Jizhong [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); Wang, Dezhen, E-mail: wangdez@dlut.edu.cn [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
2016-11-01
Highlights: • The in-out divertor asymmetry is studied using SOLPS. • The discharge operation and the magnetic filed have a great influence on the divertor asymmetry. • The asymmetry is not obvious in low recycling regime as that in high recycling regime. - Abstract: This paper aims to investigate the reason why the divertor in-out asymmetry was not obvious as experimentally observed in EAST only considering the classical drifts from previous simulations (Guo et al., J. Nucl. Mater. 438 (2013) 280; Du et al., J. Nucl. Mater. 463 (2015) 485). With consideration of the classical drifts, a series of different typical discharge scenarios in EAST in different magnetic field geometries were simulated by using the SOLPS5.2 code package. The simulated results reveal that the classical drifts make a major contribution to the in-out divertor asymmetry in the high recycling regime (HRR) and partial detachment (one divertor target begins to detach, while the other divertor remains attached) regime. In comparison, in low recycling regime the classical drifts play a much smaller role in the contributions to the in-out divertor asymmetry, which can explain reasonably the reason for it in Guo et al. (J. Nucl. Mater. 438 (2013) 280). In addition, the magnetic field geometry also has a great impact on the classical drifts inducing the asymmetry; it is found that for lower single-null, upper single-null and connected double-null topologies, in HRR the classical drifts play an dominant role in the contribution to the in-out divertor asymmetry, while for a disconnected double null magnetic field configuration, they play a minor role, which is the reason why the in-out asymmetry was unobvious by considering the drifts in Du et al. (J. Nucl. Mater. 463 (2015) 485).
Energy Technology Data Exchange (ETDEWEB)
Zheng, Weixiong [Texas A & M Univ., College Station, TX (United States); Wang, Yaqi [Idaho National Lab. (INL), Idaho Falls, ID (United States); DeHart, Mark D. [Idaho National Lab. (INL), Idaho Falls, ID (United States)
2016-09-01
In this report, we present a new upwinding scheme for the multiscale capability in Rattlesnake, the MOOSE based radiation transport application. Comparing with the initial implementation of multiscale utilizing Lagrange multipliers to impose strong continuity of angular flux on interface of in-between subdomains, this scheme does not require the particular domain partitioning. This upwinding scheme introduces discontinuity of angular flux and resembles the classic upwinding technique developed for solving first order transport equation using discontinuous finite element method (DFEM) on the subdomain interfaces. Because this scheme restores the causality of radiation streaming on the interfaces, significant accuracy improvement can be observed with moderate increase of the degrees of freedom comparing with the continuous method over the entire solution domain. Hybrid SN-PN is implemented and tested with this upwinding scheme. Numerical results show that the angular smoothing required by Lagrange multiplier method is not necessary for the upwinding scheme.
Revisit boundary conditions for the self-adjoint angular flux formulation
Energy Technology Data Exchange (ETDEWEB)
Wang, Yaqi [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gleicher, Frederick N. [Idaho National Lab. (INL), Idaho Falls, ID (United States)
2015-03-01
We revisit the boundary conditions for SAAF. We derived the equivalent parity variational form ready for coding up. The more rigorous approach of evaluating odd parity should be solving the odd parity equation coupled with the even parity. We proposed a symmetric reflecting boundary condition although neither positive definiteness nor even-odd decoupling is achieved. A simple numerical test verifies the validity of these boundary conditions.
Bounded solutions of self-adjoint second order linear difference equations with periodic coeffients
Directory of Open Access Journals (Sweden)
Encinas A.M.
2018-02-01
Full Text Available In this work we obtain easy characterizations for the boundedness of the solutions of the discrete, self–adjoint, second order and linear unidimensional equations with periodic coefficients, including the analysis of the so-called discrete Mathieu equations as particular cases.
Oscillation and nonoscillation of solutions to even order self-adjoint differential equations
Directory of Open Access Journals (Sweden)
Ondrej Dosly
2003-11-01
Full Text Available We establish oscillation and nonoscilation criteria for the linear differential equation $$ (-1^nig(t^alpha y^{(n}ig^{(n}- frac{gamma_{n,alpha}}{t^{2n-alpha}}y=q(ty,quad alpha otin {1, 3, dots , 2n-1}, $$ where $$ gamma_{n,alpha}=frac{1}{4^n}prod_{k=1}^n(2k-1-alpha^2 $$ and $q$ is a real-valued continuous function. It is proved, using these criteria, that the equation $$ (-1^nig(t^alpha y^{(n}ig^{(n} -ig(frac{gamma_{n,alpha}}{t^{2n-alpha}} + frac{gamma}{t^{2n-alpha}lg^2 t}igy = 0 $$ is nonoscillatory if and only if $$ gamma leq ilde gamma_{n,alpha}:= frac{1}{4^n}prod_{k=1}^n(2k-1-alpha^2 sum_{k=1}^nfrac{1}{(2k-1-alpha^2}. $$
Nordic co-operation in the field of nuclear safety research, thoughts on the future NKS program
International Nuclear Information System (INIS)
Laaksonen, Jukka
1998-01-01
Some general objectives for the Nordic co-operation stay for the foreseeable future. Maybe the most important of the objectives is building and maintaining a strong Nordic network between experts who work in this area. This network must be extended to the working level and to the young generation. Younger people must have similar opportunities to the co-operation as the older generation which is now in leading positions, and which to day has many other mutual contacts besides the Nordic frame. Another important objective is to build common Nordic views and to promote together our ideas in wider circles such as EU. Together we would be more influential than separately. In some fields, especially in the radioecology and emergency planning, joining the forces and sharing the common work in a co-ordinated manner could increase productivity and help to avoid overlapping work. The emphasis should be in production, communication, and systematic presentation of the research results, rather than making joint policy or common recommendations. Although the Nordic technology and the Nordic culture have similarities as compared with the rest of the world, there are differences which do not permit easy adoption of common rules and regulations. For instance, the relations between nuclear industry and nuclear regulators are not similar in Sweden and in Finland, and the entire regulatory approach is based on different philosophies. The regulatory organisations of each Nordic country are arranged and attached to the national government structure in a different way. Attempts towards harmonisation should be continued, but it is not the task of the research community and certainly not the objective of the NKS. (EG)
Directory of Open Access Journals (Sweden)
Lee L . Mason
2016-11-01
Full Text Available Over the past few years an increasing number of schools and community organizations have developed transformative learning spaces referred to as “MakerSpaces” for research and training purposes. MakerSpaces are organizations in which members sharing similar interests in science, technology, engineering, and math (STEM gather to work on self-selected projects. Proponents of MakerSpaces highlight the implicit benefits arising from participants’ increased engagement with complex technical content in a voluntary, authentic context. We extend the MakerSpace concept to applications of training special education teachers to address the needs of students with Autism Spectrum Disorder (ASD. Applied behavior analysis (ABA has vast empirical support for treating ASD. We believe the MakerSpace model provides a platform for developing a new generation of special education teachers. However, rather than making novel products, the focus is on shaping the behavior-analytic repertoires of special education teachers. In the field of ABA, the term “shaping” describes the differential reinforcement of successive approximations to a target behavior. Accordingly, we propose the name ShaperSpace to describe a novel clinical training approach to developing special education teachers who employ research-validated interventions for individuals with ASD. The supervision model described in this article is provided, not as a recommendation, but as an exemplar that has developed over four years’ contingency shaping and continues to be refined. We appeal to the reader to consider the ShaperSpace as a starting point from which skills developed through free-operant field experiences will ultimately be shaped and selected by the naturally occurring contingencies of the environment.
Wood, S. J.; Campbell, D. J.; Reschke, M. F.; Prather, L.; Clement, G.
2016-01-01
The translational Vestibulo-Ocular Reflex (tVOR) is an important otolith-mediated response to stabilize gaze during natural locomotion. One goal of this study was to develop a measure of the tVOR using a simple hand-operated chair that provided passive vertical motion. Binocular eye movements were recorded with a tight-fitting video mask in ten healthy subjects. Vertical motion was provided by a modified spring-powered chair (swopper.com) at approximately 2 Hz (+/- 2 cm displacement) to approximate the head motion during walking. Linear acceleration was measured with wireless inertial sensors (Xsens) mounted on the head and torso. Eye movements were recorded while subjects viewed near (0.5m) and far (approximately 4m) targets, and then imagined these targets in darkness. Subjects also provided perceptual estimates of target distances. Consistent with the kinematic properties shown in previous studies, the tVOR gain was greater with near targets, and greater with vision than in darkness. We conclude that this portable chair system can provide a field measure of otolith-ocular function at frequencies sufficient to elicit a robust tVOR.
A 10 mK scanning tunneling microscope operating in ultra high vacuum and high magnetic fields.
Assig, Maximilian; Etzkorn, Markus; Enders, Axel; Stiepany, Wolfgang; Ast, Christian R; Kern, Klaus
2013-03-01
We present design and performance of a scanning tunneling microscope (STM) that operates at temperatures down to 10 mK providing ultimate energy resolution on the atomic scale. The STM is attached to a dilution refrigerator with direct access to an ultra high vacuum chamber allowing in situ sample preparation. High magnetic fields of up to 14 T perpendicular and up to 0.5 T parallel to the sample surface can be applied. Temperature sensors mounted directly at the tip and sample position verified the base temperature within a small error margin. Using a superconducting Al tip and a metallic Cu(111) sample, we determined an effective temperature of 38 ± 1 mK from the thermal broadening observed in the tunneling spectra. This results in an upper limit for the energy resolution of ΔE = 3.5 kBT = 11.4 ± 0.3 μeV. The stability between tip and sample is 4 pm at a temperature of 15 mK as demonstrated by topography measurements on a Cu(111) surface.
Energy Technology Data Exchange (ETDEWEB)
Borg, Lori [Univ. of Wisconsin, Madison, WI (United States); Tobin, David [Univ. of Wisconsin, Madison, WI (United States); Reale, Anthony [National Oceanic and Atmospheric Administration (NOAA), Washington, DC (United States); Knuteson, Robert [Univ. of Wisconsin, Madison, WI (United States); Feltz, Michelle [Univ. of Wisconsin, Madison, WI (United States); Liu, Mark [National Oceanic and Atmospheric Administration (NOAA), Washington, DC (United States); Holdridge, Donna J [Argonne National Lab. (ANL), Argonne, IL (United States); Mather, James [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2017-06-01
This IOP has been a coordinated effort involving the U.S. Department of Energy (DOE) Atmospheric Radiation (ARM) Climate Research Facility, the University of Wisconsin (UW)-Madison, and the JPSS project to validate SNPP NOAA Unique Combined Atmospheric Processing System (NUCAPS) temperature and moisture sounding products from the Cross-track Infrared Sounder (CrIS) and the Advanced Technology Microwave Sounder (ATMS). In this arrangement, funding for radiosondes was provided by the JPSS project to ARM. These radiosondes were launched coincident with the SNPP satellite overpasses (OP) at four of the ARM field sites beginning in July 2012 and running through September 2017. Combined with other ARM data, an assessment of the radiosonde data quality was performed and post-processing corrections applied producing an ARM site Best Estimate (BE) product. The SNPP targeted radiosondes were integrated into the NOAA Products Validation System (NPROVS+) system, which collocated the radiosondes with satellite products (NOAA, National Aeronautics and Space Administration [NASA], European Organisation for the Exploitation of Meteorological Satellites [EUMETSAT], Geostationary Operational Environmental Satellite [GOES], Constellation Observing System for Meteorology, Ionosphere, and Climate [COSMIC]) and Numerical Weather Prediction (NWP forecasts for use in product assessment and algorithm development. This work was a fundamental, integral, and cost-effective part of the SNPP validation effort and provided critical accuracy assessments of the SNPP temperature and water vapor soundings.
Energy Technology Data Exchange (ETDEWEB)
Rogers, W.R.
1986-01-03
This research program will evaluate the aversive character of exposure to 60 Hz electric fields by determining the threshold intensity which produces avoidance or escape responses, will estimate the threshold intensity for detection of 60 Hz electric fields, will assess effects of chronic exposure to 60 Hz electric fields on the performance of two operant conditioning tasks, fixed ratio and differential reinforcement of low rate responding, will investigate, using the systematic quantitative observational sampling methods of primatology, the possible stress-inducing effects of chronic exposure to 60 Hz electric fields on the behavior of baboons living in small social groups. In all experiments, the electric fields will be described, characterized, and controlled to account for recognized artifacts associated with high intensity 60 Hz electric fields and the health of all subjects will be described using the methods of primate veterinary medicine.
International Nuclear Information System (INIS)
Liu, C.-T.; Lee, S.-C.
2006-01-01
A detailed approach for analyzing magnetic field distributions of a single-sided axial-flux permanent magnet motor with center poles will be provided. Based on the devised flux model, the related position-dependent torque and axial force of the motor can be systematically developed. By incorporating adequate control designs, the optimal operational performance of the motor system can be conveniently achieved. Results showed that not only the motor structure is suitable for related military and transportation applications, but also the magnetic field model can provide appropriate mathematical basis for relative operational realizations
Directory of Open Access Journals (Sweden)
Giuseppe CAFORIO
2014-10-01
Full Text Available This article deals with the problems of anxiety, stress and psychological discomfort that can affect soldiers sent on asymmetric warfare operations. It is based on secondary analysis of the data of two important field researches whose results have recently (2013 been published. Although the two researches adopted different methodologies, the testimonies are fully comparable and show that soldiers from different countries and cultures display common or similar reactions when they are placed in the stress conditions that the asymmetric environment involves. The approach of the paper is drawn up in such a way as to make the reader a participating observer of the reality of such missions. It is therefore centered on the personal testimonies of the soldiers interviewed in the two researches, testimonies reported just as they are, in their simplicity and, often, drama, with comments by the author kept to a minimum in order to give readers ample opportunity to evaluate and interpret the reported texts on their own. The research data, drawn from the declarations of those directly concerned, reveal the existence of a problem of psychological distress resulting from deployment in asymmetric warfare situations that is in part different in the causes of the problems resulting from deployment in traditional combat and affects percentages of participating soldiers that are not high but definitely significant. The highest incidence appears to be constituted by problems relating to reintegration into normal social and working life upon returning from the mission. This is followed in percentage terms by anxiety situations relating to life far from the family, due in large part to a sense of powerlessness for the scant possibility of managing family situations that may have cropped up or already existed beforehand.
Energy Technology Data Exchange (ETDEWEB)
Wang, Guiding [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy and Plasma Science and Technology Inst. (PSTI); Peebles, W. A. [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy and Plasma Science and Technology Inst. (PSTI); Doyle, E. J. [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy and Plasma Science and Technology Inst. (PSTI); Crocker, N. A. [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy and Plasma Science and Technology Inst. (PSTI); Wannberg, C. [Univ. of California, Los Angeles, CA (United States). Dept. of Physics and Astronomy and Plasma Science and Technology Inst. (PSTI); Lau, Cornwall H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hanson, Gregory R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Doane, John L. [General Atomics, San Diego, CA (United States)
2017-10-19
The present design concept for the ITER low-field-side reflectometer transmission line (TL) consists of an ~40 m long, 6.35 cm diameter helically corrugated waveguide (WG) together with ten 90° miter bends. This paper presents an evaluation of the TL performance at low frequencies (33-50 GHz) where the predicted HE11 mode ohmic and mode conversion losses start to increase significantly. Quasi-optical techniques were used to form a near Gaussian beam to efficiently couple radiation in this frequency range into the WG. We observed that the output beams from the guide remained linearly polarized with cross-polarization power levels of ~1.5%-3%. The polarization rotation due to the helical corrugations was in the range ~1°-3°. The radiated beam power profiles typically show excellent Gaussian propagation characteristics at distances >20 cm from the final exit aperture. The round trip propagation loss was found to be ~2.5 dB at 50 GHz and ~6.5 dB at 35 GHz, showing an inverse increase with frequency. This was consistent with updated calculations of miter bend and ohmic losses. At low frequencies (33-50 GHz), the mode purity remained very good at the exit of the waveguide, and the losses are perfectly acceptable for operation in ITER. Finally, the primary challenge may come from the future addition of a Gaussian telescope and other filter components within the corrugated guide, which will likely introduce additional perturbations to the beam profile and an increase in mode-conversion loss.
Cao, Xiangyu; Le Doussal, Pierre; Rosso, Alberto; Santachiara, Raoul
2018-04-01
We study transitions in log-correlated random energy models (logREMs) that are related to the violation of a Seiberg bound in Liouville field theory (LFT): the binding transition and the termination point transition (a.k.a., pre-freezing). By means of LFT-logREM mapping, replica symmetry breaking and traveling-wave equation techniques, we unify both transitions in a two-parameter diagram, which describes the free-energy large deviations of logREMs with a deterministic background log potential, or equivalently, the joint moments of the free energy and Gibbs measure in logREMs without background potential. Under the LFT-logREM mapping, the transitions correspond to the competition of discrete and continuous terms in a four-point correlation function. Our results provide a statistical interpretation of a peculiar nonlocality of the operator product expansion in LFT. The results are rederived by a traveling-wave equation calculation, which shows that the features of LFT responsible for the transitions are reproduced in a simple model of diffusion with absorption. We examine also the problem by a replica symmetry breaking analysis. It complements the previous methods and reveals a rich large deviation structure of the free energy of logREMs with a deterministic background log potential. Many results are verified in the integrable circular logREM, by a replica-Coulomb gas integral approach. The related problem of common length (overlap) distribution is also considered. We provide a traveling-wave equation derivation of the LFT predictions announced in a precedent work.
Energy Technology Data Exchange (ETDEWEB)
Dattoli, Giuseppe; Torre, Amalia [ENEA, Centro Ricerche Frascati, Rome (Italy). Dipt. Innovazione; Ottaviani, Pier Luigi [ENEA, Centro Ricerche Bologna (Italy); Vasquez, Luis [Madris, Univ. Complutense (Spain). Dept. de Matemateca Aplicado
1997-10-01
The finite-difference based integration method for evolution-line equations is discussed in detail and framed within the general context of the evolution operator picture. Exact analytical methods are described to solve evolution-like equations in a quite general physical context. The numerical technique based on the factorization formulae of exponential operator is then illustrated and applied to the evolution-operator in both classical and quantum framework. Finally, the general view to the finite differencing schemes is provided, displaying the wide range of applications from the classical Newton equation of motion to the quantum field theory.
Energy Technology Data Exchange (ETDEWEB)
Lee, Seung Min, E-mail: jewellee@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of); Lee, Hyun Chul, E-mail: leehc@kaeri.re.kr [Korea Atomic Energy Research Institute, 305-353, 989-111 Daedeok-daero, Yuseong-gu, Daejeon (Korea, Republic of); Ha, Jun Su, E-mail: junsu.ha@kustar.ac.ae [Department of Nuclear Engineering, Khalifa University of Science Technology and Research, Abu Dhabi P.O. Box 127788 (United Arab Emirates); Seong, Poong Hyun, E-mail: phseong@kaist.ac.kr [Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea, Republic of)
2016-10-15
Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires
International Nuclear Information System (INIS)
Lee, Seung Min; Lee, Hyun Chul; Ha, Jun Su; Seong, Poong Hyun
2016-01-01
Highlights: • A digital device-based work verification and cooperation support system was developed. • Requirements were derived by interviewing field operators having experiences with mobile-based work support systems. • The usability of the proposed system was validated by conducting questionnaire surveys. • The proposed system will be useful if the manual or the set of guidelines is well constructed. - Abstract: Digital technologies have been applied in the nuclear field to check task results, monitor events and accidents, and transmit/receive data. The results of using digital devices have proven that these devices can provide high accuracy and convenience for workers, allowing them to obtain obvious positive effects by reducing their workloads. In this study, as one step forward, a digital device-based cooperation support system, the nuclear cooperation support and mobile documentation system (Nu-COSMOS), is proposed to support communication between main control room (MCR) operators and field workers by verifying field workers’ work results in nuclear power plants (NPPs). The proposed system consists of a mobile based information storage system to support field workers by providing various functions to make workers more trusted by MCR operators; also to improve the efficiency of meeting, and a large screen based information sharing system supports meetings by allowing both sides to share one medium. The usability of this system was estimated by interviewing field operators working in nuclear power plants and experts who have experience working as operators. A survey to estimate the usability of the suggested system and the suitability of the functions of the system for field working was conducted for 35 subjects who have experience in field works or with support system development-related research. The usability test was conducted using the system usability scale (SUS), which is widely used in industrial usability evaluation. Using questionnaires
Cosmological horizons and reconstruction of quantum field theories
International Nuclear Information System (INIS)
Dappiaggi, C.; Pinamonti, N.
2007-12-01
As a starting point for this manuscript, we remark how the cosmological horizon of a certain class of Friedmann-Robertson-Walker backgrounds shares some non trivial geometric properties with null infinity in an asymptotically flat spacetime. Such a feature is generalized to a larger class of expanding spacetimes M admitting a geodesically complete cosmological horizon J - common to all co-moving observers. This property is later exploited in order to recast, in a cosmological background, some recent results for a linear scalar quantum field theory in spacetimes asymptotically flat at null infinity. Under suitable hypotheses on M - valid for de Sitter spacetime and some other FRW spacetimes obtained by perturbing deSitter space - the algebra of observables for a Klein-Gordon field is mapped into a subalgebra of the algebra of observables W(J - ) constructed on the cosmological horizon. There is exactly one pure quasifree state λ on W(J - ) which fulfills a suitable energy positivity condition with respect to a generator related with the cosmological time displacements. Furthermore λ induces a preferred physically meaningful quantum state λ M for the quantum theory in the bulk. If M admits a timelike Killing generator preserving J - , then the associated self-adjoint generator in the GNS representation of λ M has positive spectrum (i.e. energy). Moreover λ M turns out to be invariant under every symmetry of the bulk metric which preserves the cosmological horizon. In the case of an expanding de Sitter spacetime, λ M coincides with the Euclidean (Bunch-Davies) vacuum state, hence being Hadamard in this case. Remarks on the validity of the Hadamard property for λ M in more general spacetimes are presented. (orig.)
Cosmological horizons and reconstruction of quantum field theories
Energy Technology Data Exchange (ETDEWEB)
Dappiaggi, C.; Pinamonti, N. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik]|[Trento Univ., Povo (Italy). Istituto Nazionale di Alta Matematica ' ' F. Severi' ' - GNFM; Moretti, V. [Trento Univ. (Italy). Dipt. di Matematica]|[Istituto Nazionale di Fisica Nucleare - Gruppo Collegato di Trento, Povo (Italy)
2007-12-15
As a starting point for this manuscript, we remark how the cosmological horizon of a certain class of Friedmann-Robertson-Walker backgrounds shares some non trivial geometric properties with null infinity in an asymptotically flat spacetime. Such a feature is generalized to a larger class of expanding spacetimes M admitting a geodesically complete cosmological horizon J{sup -} common to all co-moving observers. This property is later exploited in order to recast, in a cosmological background, some recent results for a linear scalar quantum field theory in spacetimes asymptotically flat at null infinity. Under suitable hypotheses on M - valid for de Sitter spacetime and some other FRW spacetimes obtained by perturbing deSitter space - the algebra of observables for a Klein-Gordon field is mapped into a subalgebra of the algebra of observables W(J{sup -}) constructed on the cosmological horizon. There is exactly one pure quasifree state {lambda} on W(J{sup -}) which fulfills a suitable energy positivity condition with respect to a generator related with the cosmological time displacements. Furthermore {lambda} induces a preferred physically meaningful quantum state {lambda}{sub M} for the quantum theory in the bulk. If M admits a timelike Killing generator preserving J{sup -}, then the associated self-adjoint generator in the GNS representation of {lambda}{sub M} has positive spectrum (i.e. energy). Moreover {lambda}{sub M} turns out to be invariant under every symmetry of the bulk metric which preserves the cosmological horizon. In the case of an expanding de Sitter spacetime, {lambda}{sub M} coincides with the Euclidean (Bunch-Davies) vacuum state, hence being Hadamard in this case. Remarks on the validity of the Hadamard property for {lambda}{sub M} in more general spacetimes are presented. (orig.)
International Nuclear Information System (INIS)
Hollnagel, Erik; Gauthereau, Vincent
2002-11-01
This report describes the results from Phase II of a study on Operational Readiness Verification (ORV), and was carried out from October 2001 to September 2002. The work comprised a field study of ORV activities at a Swedish NPP during a planned productive outage, which allowed empirical work to be conducted in an appropriate environment with good accessibility to technical staff. One conclusion from Phase I of this project was the need to look more closely at the differences between three levels or types of tests that occur in ORV: object (component) test, system level test and (safety) function test, and to analyse the different steps of testing in order to understand the nontrivial relations between tests and safety. A second conclusion was the need to take a closer look at the organisation's ability to improvise in the sense of adjusting pre-defined plans to the actual conditions under which they are to be carried out. One outcome of Phase II is that there is no clear distinction between the three types of tests in the way they are carried out, and that they are used according to need rather than according to an internal logic or structure. In order better to understand the complexity of ORV, it was found useful to introduce concepts such as: (1) Community of Practice, defined as a small groups of people who through extensive communication developed a common sense of purpose, work-related knowledge and experience; (2) embedding, which means that all tasks and activities take place in an environment or context that may be physical, social, or historical (cultural); and (3) the Efficiency-Thoroughness Trade-Off (ETTO) principle, which characterises how people try to adjust what they do to the local conditions of work (temporal, physical and organisational). By using these terms to understand the practice of ORV, it becomes easier to understand how actions at times can be carried out in such a manner that the outcomes differ significantly from what was desired. It
Energy Technology Data Exchange (ETDEWEB)
Hollnagel, Erik [Linkoeping Univ. (Sweden). Cognitive Systems Engineering Laboratory; Gauthereau, Vincent [Linkoeping Univ. (Sweden). Quality Management
2002-11-01
This report describes the results from Phase II of a study on Operational Readiness Verification (ORV), and was carried out from October 2001 to September 2002. The work comprised a field study of ORV activities at a Swedish NPP during a planned productive outage, which allowed empirical work to be conducted in an appropriate environment with good accessibility to technical staff. One conclusion from Phase I of this project was the need to look more closely at the differences between three levels or types of tests that occur in ORV: object (component) test, system level test and (safety) function test, and to analyse the different steps of testing in order to understand the nontrivial relations between tests and safety. A second conclusion was the need to take a closer look at the organisation's ability to improvise in the sense of adjusting pre-defined plans to the actual conditions under which they are to be carried out. One outcome of Phase II is that there is no clear distinction between the three types of tests in the way they are carried out, and that they are used according to need rather than according to an internal logic or structure. In order better to understand the complexity of ORV, it was found useful to introduce concepts such as: (1) Community of Practice, defined as a small groups of people who through extensive communication developed a common sense of purpose, work-related knowledge and experience; (2) embedding, which means that all tasks and activities take place in an environment or context that may be physical, social, or historical (cultural); and (3) the Efficiency-Thoroughness Trade-Off (ETTO) principle, which characterises how people try to adjust what they do to the local conditions of work (temporal, physical and organisational). By using these terms to understand the practice of ORV, it becomes easier to understand how actions at times can be carried out in such a manner that the outcomes differ significantly from what was
Floyd, Randy G.; Cooley, Kathryn M.; Arnett, James E.; Fagan, Thomas K.; Mercer, Sterett H.; Hingle, Christine
2011-01-01
This article describes the results of three studies designed to understand better the journal operations, publishing practices, and impact of school psychology journals in recent years. The first study presents the results of a survey focusing on journal operations and peer-review practices that was completed by 61 journal editors of school…
Energy Technology Data Exchange (ETDEWEB)
Wakui, Tetsuya; Yamaguchi, Kazuya; Hashizume, Takumi [Waseda Univ., Advanced Research Inst. for Science and Engineering, Tokyo (Japan); Outa, Eisuke [Waseda Univ., Mechanical Engineering Dept., Tokyo (Japan); Tanzawa, Yoshiaki [Nippon Inst. of Technology, Mechanical Engineering Dept., Saitama (Japan)
1999-01-01
The effect of how a wind turbine generator system is operated is discussed from the viewpoint of net power extraction with wind velocity fluctuation in relation to the scale and the dynamic behaviour of the system. On a wind turbine generator system consisting of a Darrieus-Savonius hybrid wind turbine, a load generator and a battery, we took up two operating methods: constant tip speed ratio operation for a stand-alone system (Scheme 1) and synchronous operation by connecting a grid (Scheme 2). With our simulation model, using the result of the net extracting power, we clarified that Scheme 1 is more effective than Scheme 2 for small-scale systems. Furthermore, in Scheme 1, the appropriate rated power output of the system under each wind condition can be confirmed. (Author)
International Nuclear Information System (INIS)
Dadashyan, K.Yu.; Khoruzhii, S.S.
1987-01-01
The construction of a modular theory for weakly closed J-involutive algebras of bounded operators on Pontryagin spaces is continued. The spectrum of the modular operator Δ of such an algebra is investigated, the existence of a strongly continuous J-unitary group is established and, under the condition that the spectrum lies in the right half-plane, Tomita's fundamental theorem is proved
International Nuclear Information System (INIS)
Hollnagel, Erik; Gauthereau, Vincent; Persson, Bodil
2004-01-01
This report describes the results from Phase III of a study on Operational Readiness Verification (ORV) that was carried out from December 2002 to November 2003. The work comprised a field study of ORV activities at a Swedish NPP during a planned productive outage [subavstaellning], which allowed empirical work to be conducted in an appropriate environment with good accessibility to technical staff. One conclusion from Phase I of this project was the need to look more closely at the differences between three levels or types of tests that occur in ORV: object (component) test, system level test and (safety) function test, and to analyse the different steps of testing in order to understand the nontrivial relations between tests and safety. A second conclusion was the need to take a closer look at the organisation's ability to improvise in the sense of adjusting pre-defined plans to the actual conditions under which they are to be carried out. Phase II of the project found that although all three types of test occurred, they were rather used according to need rather than to a predefined arrangement or procedure. The complexity of ORV could be understood and described by using the concepts of Community of Practice, embedding, and Efficiency-Thoroughness Trade-Off. In addition, organisation and the different communities of practice improvise by adjusting pre-defined plans or work orders to the existing conditions. Such improvisations take place both on the levels of individual actions, on the level of communities of practice, and on the organisational level. The ability to improvise is practically a necessity for work to be carried out, but is also a potential risk. Phase III of the project studied how tasks are adapted relative to the different types of embedding and the degree of correspondence between nominal and actual ORV. It also looked further at the different Communities of Practice that are part of maintenance and ORV, focusing on the coordination and
Energy Technology Data Exchange (ETDEWEB)
Hollnagel, Erik [Linkoeping Univ. (Sweden). Dept. of Computer and Information Science; Gauthereau, Vincent; Persson, Bodil [Linkoeping Univ. (Sweden). Dept. of Industrial Engineering
2004-01-01
This report describes the results from Phase III of a study on Operational Readiness Verification (ORV) that was carried out from December 2002 to November 2003. The work comprised a field study of ORV activities at a Swedish NPP during a planned productive outage, which allowed empirical work to be conducted in an appropriate environment with good accessibility to technical staff. One conclusion from Phase I of this project was the need to look more closely at the differences between three levels or types of tests that occur in ORV: object (component) test, system level test and (safety) function test, and to analyse the different steps of testing in order to understand the nontrivial relations between tests and safety. A second conclusion was the need to take a closer look at the organisation's ability to improvise in the sense of adjusting pre-defined plans to the actual conditions under which they are to be carried out. Phase II of the project found that although all three types of test occurred, they were rather used according to need rather than to a predefined arrangement or procedure. The complexity of ORV could be understood and described by using the concepts of Community of Practice, embedding, and Efficiency-Thoroughness Trade-Off. In addition, organisation and the different communities of practice improvise by adjusting pre-defined plans or work orders to the existing conditions. Such improvisations take place both on the levels of individual actions, on the level of communities of practice, and on the organisational level. The ability to improvise is practically a necessity for work to be carried out, but is also a potential risk. Phase III of the project studied how tasks are adapted relative to the different types of embedding and the degree of correspondence between nominal and actual ORV. It also looked further at the different Communities of Practice that are part of maintenance and ORV, focusing on the coordination and communication between
International Nuclear Information System (INIS)
Karimi-Alavijeh, H.R.; Ehsani, A.
2015-01-01
In this paper, we have investigated experimentally the effect of different drain/source (D/S) electrodes and charge injection buffer layers on the electrical properties and operational stability of a stilbene organic field effect transistor (OFET). The results show that the organic buffer layer of copper phthalocyanine (CuPc) considerably improves the electrical properties of the transistors, but has a negligible effect on their temporal behavior. On the other hand, inorganic metal-oxide buffer layer of molybdenum oxide (MoO 3 ) drastically changes both the electrical properties and operational stability. The functionalities of this metal-oxide tightly depend on the properties of the D/S metallic electrodes. OFETs with Al/MoO 3 as the bilayer D/S electrodes have the best electrical properties: field effect mobility μ eff = 0.32 cm 2 V −1 s −1 and threshold voltage V TH = − 5 V and the transistors with Ag/MoO 3 have the longest operational stability. It was concluded that the chemical stability of the metal/metal-oxide or metal/organic interfaces of the bilayer D/S electrodes determine the operational stability of the OFETs. - Highlights: • The effect of buffer layers on the performance of the stilbene OFETs has been investigated. • Inorganic buffer layer improved the electrical and temporal behaviors simultaneously. • Organic buffer layer only changes the electrical properties. • Chemical stability of the interfaces determines the operational stability of the transistor
International Nuclear Information System (INIS)
Primas, H.; Schleicher, M.
1975-01-01
A comprehensive review of the attempts to rephrase molecular quantum mechanics in terms of the particle density operator and the current density or phase density operator is given. All pertinent investigations which have come to attention suffer from severe mathematical inconsistencies and are not adequate to the few-body problem of quantum chemistry. The origin of the failure of these attempts is investigated, and it is shown that a realization of a local quantum field theory of molecular matter in terms of observables would presuppose the solution of many highly nontrivial mathematical problems
International Nuclear Information System (INIS)
1989-06-01
This Declaration follows upon the signing of a Protocol of intent on 3 April 1989 by VEBA, the major energy consortium in the Federal Republic of Germany supplying nuclear power, and COGEMA, the French State-owned nuclear fuel company and aims to provide a broad framework for co-operation between the two countries. The Declaration, in particular, covers co-operation in the fields of reprocessing, production of MOX fuel (mixed oxide fuel), uranium enrichment, nuclear reactors, information relating to nuclear installations, transport of nuclear material [fr