Directory of Open Access Journals (Sweden)
David N. Keck
2003-01-01
Full Text Available We investigate a class of abstract functional integro-differential stochastic evolution equations in a real separable Hilbert space. Global existence results concerning mild and periodic solutions are formulated under various growth and compactness conditions. Also, related convergence results are established and an example arising in the mathematical modeling of heat conduction is discussed to illustrate the abstract theory.
Hilbert spaces from path integrals
Energy Technology Data Exchange (ETDEWEB)
Dowker, Fay; Johnston, Steven [Theoretical Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ (United Kingdom); Sorkin, Rafael D, E-mail: f.dowker@imperial.ac.u, E-mail: steven.johnston02@imperial.ac.u, E-mail: rsorkin@perimeterinstitute.c [Perimeter Institute, 31 Caroline Street North, Waterloo ON, N2L 2Y5 (Canada)
2010-07-09
It is shown that a Hilbert space can be constructed for a quantum system starting from a framework in which histories are fundamental. The decoherence functional provides the inner product on this 'history Hilbert space'. It is also shown that the history Hilbert space is the standard Hilbert space in the case of non-relativistic quantum mechanics.
Sunder, V S
2016-01-01
The primarily objective of the book is to serve as a primer on the theory of bounded linear operators on separable Hilbert space. The book presents the spectral theorem as a statement on the existence of a unique continuous and measurable functional calculus. It discusses a proof without digressing into a course on the Gelfand theory of commutative Banach algebras. The book also introduces the reader to the basic facts concerning the various von Neumann–Schatten ideals, the compact operators, the trace-class operators and all bounded operators. .
Frames and bases in tensor products of Hilbert spaces and Hilbert C ...
Indian Academy of Sciences (India)
Amirkabir University of Technology (Tehran Polytechnic), 424, Hafez Ave.,. Tehran 15914, Iran. E-mail: khosravi−amir@yahoo.com. MS received 17 November 2005; revised 9 December 2005. Abstract. In this article, we study tensor product of Hilbert C. ∗-modules and Hilbert spaces. We show that if E is a Hilbert A-module ...
Hilbert space theory of classical electrodynamics
Indian Academy of Sciences (India)
Abstract. Classical electrodynamics is reformulated in terms of wave functions in the classical phase space of electrodynamics, following the Koopman–von Neumann–Sudarshan prescription for classical mechanics on Hilbert spaces sans the superselection rule which prohibits interference effects in classical mechanics.
International Nuclear Information System (INIS)
Exner, P.; Kolerov, G.I.
1980-01-01
A Hilbert space of paths, the elements of which are determined by trigonometric series, was proposed and used recently by Truman. This space is shown to consist precisely of all absolutely continuous paths ending in the origin with square-integrable derivatives
Dirac structures on Hilbert spaces
Directory of Open Access Journals (Sweden)
A. Parsian
1999-01-01
shown that Dirac structures on H are in one-to-one correspondence with isometries on H, and, any two Dirac structures are isometric. It is, also, proved that any Dirac structure on a smooth manifold in the sense of [1] yields a Dirac structure on some Hilbert space. The graph of any densely defined skew symmetric linear operator on a Hilbert space is, also, shown to be a Dirac structure. For a Dirac structure L on H, every z∈H is uniquely decomposed as z=p1(l+p2(l for some l∈L, where p1 and p2 are projections. When p1(L is closed, for any Hilbert subspace W⊂H, an induced Dirac structure on W is introduced. The latter concept has also been generalized.
Hilbert-type inequalities for Hilbert space operators | Krnic ...
African Journals Online (AJOL)
In this paper we establish a general form of the Hilbert inequality for positive invertible operators on a Hilbert space. Special emphasis is given to such inequalities with homogeneous kernels. In some general cases the best possible constant factors are also derived. Finally, we obtain the improvement of previously deduced ...
Teleportation schemes in infinite dimensional Hilbert spaces
International Nuclear Information System (INIS)
Fichtner, Karl-Heinz; Freudenberg, Wolfgang; Ohya, Masanori
2005-01-01
The success of quantum mechanics is due to the discovery that nature is described in infinite dimension Hilbert spaces, so that it is desirable to demonstrate the quantum teleportation process in a certain infinite dimensional Hilbert space. We describe the teleportation process in an infinite dimensional Hilbert space by giving simple examples
Frames and bases in tensor products of Hilbert spaces and Hilbert C ...
Indian Academy of Sciences (India)
In this article, we study tensor product of Hilbert *-modules and Hilbert spaces. We show that if is a Hilbert -module and is a Hilbert -module, then tensor product of frames (orthonormal bases) for and produce frames (orthonormal bases) for Hilbert A ⊗ B -module E ⊗ F , and we get more results. For Hilbert ...
Functional Analysis: Entering Hilbert Space
DEFF Research Database (Denmark)
Hansen, Vagn Lundsgaard
In the second edition, I have expanded the material on normed vector spaces and their operators presented in Chapter 1 to include proofs of the Open Map-ping Theorem, the Closed Graph Theorem and the Hahn-Banach The orem. The material on operators between normed vector spaces is further expanded...... in a new chapter on Fredholm theory (Chapter 6). Fredholm theory originates in pioneering work of the Swedish mathematician Erik Ivar Fred-holm on integral equations, which inspired the study of a new class of bounded linear operators, known as Fredholm operators. Chapter 6 presents the basic elements...... of the theory of Fredholm operators on general Banach spaces, not only on Hilbert spaces, since this is important for applications of the theory. The more general setting with Banach spaces requires that we develop the theory of dual operators between Banach spaces to replace the use of adjoint operators...
Functional Analysis: Entering Hilbert Space
DEFF Research Database (Denmark)
Hansen, Vagn Lundsgaard
In the second edition, I have expanded the material on normed vector spaces and their operators presented in Chapter 1 to include proofs of the Open Map-ping Theorem, the Closed Graph Theorem and the Hahn-Banach The orem. The material on operators between normed vector spaces is further expanded ...... of the new material on normed vector spaces and their operators, the book can hopefully serve as a general introduction to functional analysis viewed as a theory of infinite dimensional linear spaces and linear operators acting on them.......In the second edition, I have expanded the material on normed vector spaces and their operators presented in Chapter 1 to include proofs of the Open Map-ping Theorem, the Closed Graph Theorem and the Hahn-Banach The orem. The material on operators between normed vector spaces is further expanded...... of the theory of Fredholm operators on general Banach spaces, not only on Hilbert spaces, since this is important for applications of the theory. The more general setting with Banach spaces requires that we develop the theory of dual operators between Banach spaces to replace the use of adjoint operators...
Linear systems and operators in Hilbert space
Fuhrmann, Paul A
2014-01-01
A treatment of system theory within the context of finite dimensional spaces, this text is appropriate for students with no previous experience of operator theory. The three-part approach, with notes and references for each section, covers linear algebra and finite dimensional systems, operators in Hilbert space, and linear systems in Hilbert space. 1981 edition.
Quantum theory in complex Hilbert space
International Nuclear Information System (INIS)
Sharma, C.S.
1988-01-01
The theory of complexification of a real Hilbert space as developed by the author is scrutinized with the aim of explaining why quantum theory should be done in a complex Hilbert space in preference to real Hilbert space. It is suggested that, in order to describe periodic motions in stationary states of a quantum system, the mathematical object modelling a state of a system should have enough points in it to be able to describe explicit time dependence of a periodic motion without affecting the probability distributions of observables. Heuristic evidence for such an assumption comes from Dirac's theory of interaction between radiation and matter. If the assumption is adopted as a requirement on the mathematical model for a quantum system, then a real Hilbert space is ruled out in favour of a complex Hilbert space for a possible model for such a system
A constructive presentation of rigged Hilbert spaces
International Nuclear Information System (INIS)
Celeghini, Enrico
2015-01-01
We construct a rigged Hilbert space for the square integrable functions on the line L2(R) adding to the generators of the Weyl-Heisenberg algebra a new discrete operator, related to the degree of the Hermite polynomials. All together, continuous and discrete operators, constitute the generators of the projective algebra io(2). L 2 (R) and the vector space of the line R are shown to be isomorphic representations of such an algebra and, as both these representations are irreducible, all operators defined on the rigged Hilbert spaces L 2 (R) or R are shown to belong to the universal enveloping algebra of io(2). The procedure can be extended to orthogonal and pseudo-orthogonal spaces of arbitrary dimension by tensorialization.Circumventing all formal problems the paper proposes a kind of toy model, well defined from a mathematical point of view, of rigged Hilbert spaces where, in contrast with the Hilbert spaces, operators with different cardinality are allowed. (paper)
Hilbert space methods in partial differential equations
Showalter, Ralph E
1994-01-01
This graduate-level text opens with an elementary presentation of Hilbert space theory sufficient for understanding the rest of the book. Additional topics include boundary value problems, evolution equations, optimization, and approximation.1979 edition.
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.
Transverse entanglement migration in Hilbert space
International Nuclear Information System (INIS)
Chan, K. W.; Torres, J. P.; Eberly, J. H.
2007-01-01
We show that, although the amount of mutual entanglement of photons propagating in free space is fixed, the type of correlations between the photons that determine the entanglement can dramatically change during propagation. We show that this amounts to a migration of entanglement in Hilbert space, rather than real space. For the case of spontaneous parametric down-conversion, the migration of entanglement in transverse coordinates takes place from modulus to phase of the biphoton state and back again. We propose an experiment to observe this migration in Hilbert space and to determine the full entanglement
κ-Minkowski representations on Hilbert spaces
International Nuclear Information System (INIS)
Agostini, Alessandra
2007-01-01
The algebra of functions on κ-Minkowski noncommutative space-time is studied as algebra of operators on Hilbert spaces. The representations of this algebra are constructed and classified. This new approach leads to a natural construction of integration in κ-Minkowski space-time in terms of the usual trace of operators
Projective Hilbert space structures at exceptional points
Günther, Uwe; Rotter, Ingrid; Samsonov, Boris F.
2007-07-01
A non-Hermitian complex symmetric 2 × 2-matrix toy model is used to study projective Hilbert space structures in the vicinity of exceptional points (EPs). The bi-orthogonal eigenvectors of a diagonalizable matrix are Puiseux-expanded in terms of the root vectors at the EP. It is shown that the apparent contradiction between the two incompatible normalization conditions with finite and singular behaviour in the EP-limit can be resolved by projectively extending the original Hilbert space. The complementary normalization conditions correspond then to two different affine charts of this enlarged projective Hilbert space. Geometric phase and phase-jump behaviour are analysed, and the usefulness of the phase rigidity as measure for the distance to EP configurations is demonstrated. Finally, EP-related aspects of {\\cal P}{\\cal T} -symmetrically extended quantum mechanics are discussed and a conjecture concerning the quantum brachistochrone problem is formulated.
Projective Hilbert space structures at exceptional points
Energy Technology Data Exchange (ETDEWEB)
Guenther, Uwe [Research Center Dresden-Rossendorf, PO 510119, D-01314 Dresden (Germany); Rotter, Ingrid [Max Planck Institute for the Physics of Complex Systems, D-01187 Dresden (Germany); Samsonov, Boris F [Physics Department, Tomsk State University, 36 Lenin Avenue, 634050 Tomsk (Russian Federation)
2007-07-27
A non-Hermitian complex symmetric 2 x 2-matrix toy model is used to study projective Hilbert space structures in the vicinity of exceptional points (EPs). The bi-orthogonal eigenvectors of a diagonalizable matrix are Puiseux-expanded in terms of the root vectors at the EP. It is shown that the apparent contradiction between the two incompatible normalization conditions with finite and singular behaviour in the EP-limit can be resolved by projectively extending the original Hilbert space. The complementary normalization conditions correspond then to two different affine charts of this enlarged projective Hilbert space. Geometric phase and phase-jump behaviour are analysed, and the usefulness of the phase rigidity as measure for the distance to EP configurations is demonstrated. Finally, EP-related aspects of PT-symmetrically extended quantum mechanics are discussed and a conjecture concerning the quantum brachistochrone problem is formulated.
The role of the rigged Hilbert space in quantum mechanics
International Nuclear Information System (INIS)
Madrid, Rafael de la
2005-01-01
There is compelling evidence that, when a continuous spectrum is present, the natural mathematical setting for quantum mechanics is the rigged Hilbert space rather than just the Hilbert space. In particular, Dirac's braket formalism is fully implemented by the rigged Hilbert space rather than just by the Hilbert space. In this paper, we provide a pedestrian introduction to the role the rigged Hilbert space plays in quantum mechanics, by way of a simple, exactly solvable example. The procedure will be constructive and based on a recent publication. We also provide a thorough discussion on the physical significance of the rigged Hilbert space
Hilbert space theory of classical electrodynamics
Indian Academy of Sciences (India)
Wigner function can be implemented by classical optics. This may be useful in interpreting quantum information processing in terms of classical optics. Keywords. Hilbert space; Koopman–von Neumann theory; classical electrodynamics. PACS No. 03.50.De. 1. Introduction. Much recent work has unexpectedly revealed that ...
On typical properties of Hilbert space operators
Eisner, T.; Mátrai, T.
2013-01-01
We study the typical behavior of bounded linear operators on infinite-dimensional complex separable Hilbert spaces in the norm, strong-star, strong, weak polynomial and weak topologies. In particular, we investigate typical spectral properties, the problem of unitary equivalence of typical
Characterization of projection lattices of Hilbert spaces
Energy Technology Data Exchange (ETDEWEB)
Szambien, H.H.
1986-09-01
The classical lattices of projections of Hilbert spaces over the real, the complex or the quaternion number field are characterized among the totality of irreducible, complete, orthomodular, atomic lattices satisfying the covering property. To this end, so-called paratopological lattices are introduced, i.e, lattices carrying a topology that renders the lattice operations restrictedly continuous.
Quasistationary sequences in Hilbert spaces | Muriuki | African ...
African Journals Online (AJOL)
In this paper the concept of covariance differences of a sequence is introduced and its relationship with the covariance function is established. The criteria of linear representability of sequences in Hilbert space are proved. The necessary and sufficient conditions for a linearly representable sequence to be quasistationary ...
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...
Functional Analysis: Entering Hilbert Space
DEFF Research Database (Denmark)
Hansen, Vagn Lundsgaard
In the second edition, I have expanded the material on normed vector spaces and their operators presented in Chapter 1 to include proofs of the Open Map-ping Theorem, the Closed Graph Theorem and the Hahn-Banach The orem. The material on operators between normed vector spaces is further expanded ...
Master Space, Hilbert Series and Seiberg Duality
Forcella, Davide; Zaffaroni, Alberto
2009-01-01
We analyze the action of Toric (Seiberg) duality on the combined mesonic and baryonic moduli space of quiver gauge theories obtained from D3 branes at Calabi-Yau singularities. We analyze in particular the structure of the master space, the complete moduli space for one brane, for different toric phases of a given singularity. We show that the Hilbert Series for the largest component of the master space of different phases is the same, when refined with all the non anomalous charges. This reflects the fact that the quiver gauge theories associated with different phases are related by Seiberg duality when the number of branes is greater than one.
Semiclassical propagation: Hilbert space vs. Wigner representation
Gottwald, Fabian; Ivanov, Sergei D.
2018-03-01
A unified viewpoint on the van Vleck and Herman-Kluk propagators in Hilbert space and their recently developed counterparts in Wigner representation is presented. Based on this viewpoint, the Wigner Herman-Kluk propagator is conceptually the most general one. Nonetheless, the respective semiclassical expressions for expectation values in terms of the density matrix and the Wigner function are mathematically proven here to coincide. The only remaining difference is a mere technical flexibility of the Wigner version in choosing the Gaussians' width for the underlying coherent states beyond minimal uncertainty. This flexibility is investigated numerically on prototypical potentials and it turns out to provide neither qualitative nor quantitative improvements. Given the aforementioned generality, utilizing the Wigner representation for semiclassical propagation thus leads to the same performance as employing the respective most-developed (Hilbert-space) methods for the density matrix.
The Hilbert space of conditional clauses
Francis, Charles
2015-05-01
In the absence of a satisfactory interpretation of quantum theory, physical law lacks physical basis. This paper reviews the orthodox, or Dirac-von Neumann interpretation, and makes explicit that Hilbert space describes propositions about measurement results. Kets are defined as conditional clauses referring to measurements in a formal language. It is seen that these clauses are elements of a Hilbert space, such that addition is logical disjunction, the dual space consists of consequent clauses, and the inner product is a set of statements in the subjunctive mood. The probability interpretation gives truth values for corresponding future tense statements when the initial state is actually prepared and the final state is to be measured. The mathematical structure of quantum mechanics is formulated in terms of discrete measurement results at finite level of accuracy and does not depend on an assumption of a substantive, or background, space-time continuum. A continuum of kets, ∣x> for x ∈ ℝ3, is constructed from linear combinations of kets in a finite basis. The inner product can be expressed either as a finite sum or as an integral. Discrete position functions are uniquely embedded into smooth wave functions in such a way that differential operators are defined. It is shown that the choice of basis has no effect on underlying physics (quantum covariance). The Dirac delta has a representation as a smooth function. Operators do not in general have an integral form. The Schrödinger equation is shown from the requirements of the probability interpretation. It is remarked that a formal construction of quantum electrodynamics (qed) avoiding divergence problems has been completed using finite dimensional Hilbert space. I conclude that quantum mechanics makes statements about the world with clear physical meaning, such that space is emergent from particle interactions and has no fundamental role.
On a functional equation over Hilbert spaces
International Nuclear Information System (INIS)
Thaheem, A.B.; Mohammad, N.
1988-06-01
Let {u t :t is an element of R} and {v t :t is an element of R} be commuting one-parameter groups of unitary operators on a Hilbert space H such that u t +u -t =v t +v -t for all t is an element of R. It is shown here that H can be decomposed into two parts by a projection p such that u t =v t on pH and u t =v -t on (1-p)H. (author). 13 refs
Open superstring field theory on the restricted Hilbert space
International Nuclear Information System (INIS)
Konopka, Sebastian; Sachs, Ivo
2016-01-01
It appears that the formulation of an action for the Ramond sector of open superstring field theory requires to either restrict the Hilbert space for the Ramond sector or to introduce auxiliary fields with picture −3/2. The purpose of this note is to clarify the relation of the restricted Hilbert space with other approaches and to formulate open superstring field theory entirely in the small Hilbert space.
Quantum mechanics in an evolving Hilbert space
Artacho, Emilio; O'Regan, David D.
2017-03-01
Many basis sets for electronic structure calculations evolve with varying external parameters, such as moving atoms in dynamic simulations, giving rise to extra derivative terms in the dynamical equations. Here we revisit these derivatives in the context of differential geometry, thereby obtaining a more transparent formalization, and a geometrical perspective for better understanding the resulting equations. The effect of the evolution of the basis set within the spanned Hilbert space separates explicitly from the effect of the turning of the space itself when moving in parameter space, as the tangent space turns when moving in a curved space. New insights are obtained using familiar concepts in that context such as the Riemann curvature. The differential geometry is not strictly that for curved spaces as in general relativity, a more adequate mathematical framework being provided by fiber bundles. The language used here, however, will be restricted to tensors and basic quantum mechanics. The local gauge implied by a smoothly varying basis set readily connects with Berry's formalism for geometric phases. Generalized expressions for the Berry connection and curvature are obtained for a parameter-dependent occupied Hilbert space spanned by nonorthogonal Wannier functions. The formalism is applicable to basis sets made of atomic-like orbitals and also more adaptative moving basis functions (such as in methods using Wannier functions as intermediate or support bases), but should also apply to other situations in which nonorthogonal functions or related projectors should arise. The formalism is applied to the time-dependent quantum evolution of electrons for moving atoms. The geometric insights provided here allow us to propose new finite-difference time integrators, and also better understand those already proposed.
Hilbert asymptotic expansion method for evolution equations in Banach spaces
International Nuclear Information System (INIS)
Mika, J.
1978-01-01
In the paper an abstract initial value problem for a singularly perturbed linear evolution equation in a Banach space is considered. The evolution operator consists of two operators. One of them having an eigenvalue at the origin is multiplied by 1/epsilon where epsilon is a small positive parameter. The Hilbert expansion method is applied to solving the problem and the asymptotic solution is shown to converge uniformly to the exact one with epsilon tending to zero. The results of the paper are applicable to the linear Boltzmann equation if the scattering operator is bounded and the streaming operator is represented in the finite-differnce form. As an example, the Boltzmann equation for neutrons is considered and the Hilbert expansion used to derive the diffusion equation. (author)
Multipliers for continuous frames in Hilbert spaces
International Nuclear Information System (INIS)
Balazs, P; Bayer, D; Rahimi, A
2012-01-01
In this paper, we examine the general theory of continuous frame multipliers in Hilbert space. These operators are a generalization of the widely used notion of (discrete) frame multipliers. Well-known examples include anti-Wick operators, STFT multipliers or Calderón–Toeplitz operators. Due to the possible peculiarities of the underlying measure spaces, continuous frames do not behave quite as their discrete counterparts. Nonetheless, many results similar to the discrete case are proven for continuous frame multipliers as well, for instance compactness and Schatten-class properties. Furthermore, the concepts of controlled and weighted frames are transferred to the continuous setting. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’. (paper)
Rigged Hilbert spaces and topologies on operator algebras
International Nuclear Information System (INIS)
Freidrich, M.; Lassner, G.
1979-01-01
To any Oπ-algebra of unbounded operators there corresponds a rigged Hilbert space so that all operators are continuous with respect to the topologies. This leads to different topologies of uniformly bounded convergence on the operator algebra, which are investigated in this paper. Particularly consistent results are obtained if the rigged Hilbert space is a reflexive one
Tensor product of the octonionic Hilbert spaces and colour confinement
International Nuclear Information System (INIS)
Rembielinski, J.
1978-01-01
The definition of the tensor product of the octonionic Hilbert spaces with complex geometry is proposed. This definition is based on the isomorphism (geometric and algebraic) of the octonionic Hilbert space with appropriate structure. It is found that the algebraic colour confinement holds only partially. In so called essentially octonionic theories the algebraic confinement of colour holds for all boson states. (author)
Hilbert Space Operators in Quantum Physics
Blank, Jiří; Havlíček, Miloslav
2008-01-01
The second edition of this course-tested book provides a detailed and in-depth discussion of the foundations of quantum theory as well as its applications to various systems. The exposition is self-contained; in the first part the reader finds the mathematical background in chapters about functional analysis, operators on Hilbert spaces and their spectral theory, as well as operator sets and algebras. This material is used in the second part to a systematic explanation of the foundations, in particular, states and observables, properties of canonical variables, time evolution, symmetries and various axiomatic approaches. In the third part, specific physical systems and situations are discussed. Two chapters analyze Schrödinger operators and scattering, two others added in the second edition are devoted to new important topics, quantum waveguides and quantum graphs. Some praise for the previous edition: "I really enjoyed reading this work. It is very well written, by three real experts in the field. It stands...
Coherent states and Hermite polynomials on quaternionic Hilbert spaces
Energy Technology Data Exchange (ETDEWEB)
Thirulogasanthar, K; Krzyzak, A [Department of Computer Science and Software Engineering, Concordia University, 1455 de Maisonneuve Blvd. W, Montreal, Quebec H3G 1M8 (Canada); Honnouvo, G, E-mail: santhar@cs.concordia.c, E-mail: krzyzak@cs.concordia.c, E-mail: g-honnouvo@yahoo.f [Department of Mathematics and Statistics, McGill University, 805 Sherbrooke Street West, Montreal, Quebec H3A 2K6 (Canada)
2010-09-24
Coherent states, similar to the canonical coherent states of the harmonic oscillator, labeled by quaternions are established on the right and left quaternionic Hilbert spaces. On the left quaternionic Hilbert space reproducing kernels are established. As was claimed by Adler and Millard (J. Math. Phys. 1997 38 2117-26) it is proved that these coherent states cannot be realized as a group action on a quaternionic Hilbert space. As an extension of the complex Hermite polynomials, quaternionic Hermite polynomials are defined and these polynomials are associated with an operator as eigenfunctions.
Isometric Reflection Vectors and Characterizations of Hilbert Spaces
Directory of Open Access Journals (Sweden)
Donghai Ji
2014-01-01
Full Text Available A known characterization of Hilbert spaces via isometric reflection vectors is based on the following implication: if the set of isometric reflection vectors in the unit sphere SX of a Banach space X has nonempty interior in SX, then X is a Hilbert space. Applying a recent result based on well-known theorem of Kronecker from number theory, we improve this by substantial reduction of the set of isometric reflection vectors needed in the hypothesis.
Introduction to Hilbert space and the theory of spectral multiplicity
Halmos, Paul R
2017-01-01
Concise introductory treatment consists of three chapters: The Geometry of Hilbert Space, The Algebra of Operators, and The Analysis of Spectral Measures. A background in measure theory is the sole prerequisite. 1957 edition.
Alabiso, Carlo
2015-01-01
This book is an introduction to the theory of Hilbert space, a fundamental tool for non-relativistic quantum mechanics. Linear, topological, metric, and normed spaces are all addressed in detail, in a rigorous but reader-friendly fashion. The rationale for an introduction to the theory of Hilbert space, rather than a detailed study of Hilbert space theory itself, resides in the very high mathematical difficulty of even the simplest physical case. Within an ordinary graduate course in physics there is insufficient time to cover the theory of Hilbert spaces and operators, as well as distribution theory, with sufficient mathematical rigor. Compromises must be found between full rigor and practical use of the instruments. The book is based on the author's lessons on functional analysis for graduate students in physics. It will equip the reader to approach Hilbert space and, subsequently, rigged Hilbert space, with a more practical attitude. With respect to the original lectures, the mathematical flavor in all sub...
On the Inclusion Relation of Reproducing Kernel Hilbert Spaces
Zhang, Haizhang; Zhao, Liang
2011-01-01
To help understand various reproducing kernels used in applied sciences, we investigate the inclusion relation of two reproducing kernel Hilbert spaces. Characterizations in terms of feature maps of the corresponding reproducing kernels are established. A full table of inclusion relations among widely-used translation invariant kernels is given. Concrete examples for Hilbert-Schmidt kernels are presented as well. We also discuss the preservation of such a relation under various operations of ...
DECOMPOSITION OF HILBERT-SPACE CONTRACTIONS
DENISE DE OLIVEIRA
1995-01-01
O problema de decomposição de contrações em espaços de Hilbert é motivado pelo problema do subespaço invariante, o qual é um famoso problema em aberto em Teoria de Operadores. Se T (pertence) B [H] é uma contração, define- se o operador A como o limite forte da seqüência { T* n Tn (pertence) B [H]; n > ou = 1}. Este operador caracteriza as isometrias, uma vez que T é uma isometria se e somente se A = I. A decomposição de Von Neumann-Wold para isometrias estabel...
Minimal supports in quantum logics and Hilbert space
Energy Technology Data Exchange (ETDEWEB)
Cohen, D.W.; Svetlichny, G.
1987-05-01
It is shown that if a fully atomic, complete orthomodular lattice satisfies a minimal support condition (m.s.c.), then it satisfies Piron's axioms, and is thereby shown to be the projection lattice of a generalized Hilbert space. It is shown, conversely, that m.s.c. holds in Hilbert space subspace lattices. The physical justification for m.s.c. is provided in the context of a property lattice L(A,..sigma..) for a realistic entity (A, ..sigma..) in the sense of Foulis-Piron-Randall. This content provides a clear focus on key issues in the debate over the appropriateness of requiring quantum logics to be represented over Hilbert spaces.
Nevanlinna functions, perturbation formulas, and triplets of Hilbert spaces
Hassi, Seppo; de Snoo, H
1998-01-01
Let S be a closed symmetric operator with defect numbers (1, 1) in a Hilbert space h and let A be a selfadjoint operator extension of S in h. Then S is necessarily a graph restriction of A and the selfadjoint extensions of S can be considered as graph perturbations of A, cf. [8]. Only when S is not
Ad Hoc Physical Hilbert Spaces in Quantum Mechanics
Czech Academy of Sciences Publication Activity Database
Fernandez, F. M.; Garcia, J.; Semorádová, Iveta; Znojil, Miloslav
2015-01-01
Roč. 54, č. 12 (2015), s. 4187-4203 ISSN 0020-7748 Institutional support: RVO:61389005 Keywords : quantum mechanics * physical Hilbert spaces * ad hoc inner product * singular potentials regularized * low lying energies Subject RIV: BE - Theoretical Physics Impact factor: 1.041, year: 2015
On Some Fractional Stochastic Integrodifferential Equations in Hilbert Space
Directory of Open Access Journals (Sweden)
Hamdy M. Ahmed
2009-01-01
Full Text Available We study a class of fractional stochastic integrodifferential equations considered in a real Hilbert space. The existence and uniqueness of the Mild solutions of the considered problem is also studied. We also give an application for stochastic integropartial differential equations of fractional order.
The method of moments and nested Hilbert spaces in quantum mechanics
International Nuclear Information System (INIS)
Adeniyi Bangudu, E.
1980-08-01
It is shown how the structures of a nested Hilbert space Hsub(I), associated with a given Hilbert space Hsub(O), may be used to simplify our understanding of the effects of parameters, whose values have to be chosen rather than determined variationally, in the method of moments. The result, as applied to non-relativistic quartic oscillator and helium atom, is to associate the parameters with sequences of Hilbert spaces, while the error of the method of moments relative to the variational method corresponds to a nesting operator of the nested Hilbert space. Difficulties hindering similar interpretations in terms of rigged Hilbert space structures are highlighted. (author)
The linearization of boundary eigenvalue problems and reproducing kernel Hilbert spaces
Ćurgus, Branko; Dijksma, Aad; Read, Tom
2001-01-01
The boundary eigenvalue problems for the adjoint of a symmetric relation S in a Hilbert space with finite, not necessarily equal, defect numbers, which are related to the selfadjoint Hilbert space extensions of S are characterized in terms of boundary coefficients and the reproducing kernel Hilbert
A note on the infimum problem of Hilbert space effects
International Nuclear Information System (INIS)
Yuan Li; Du Hongke
2006-01-01
The quantum effects for a physical system can be described by the set E(H) of positive operators on a complex Hilbert space H that are bounded above by the identity operator I. The infimum problem of Hilbert space effects is to find under what condition the infimum A and B exists for two quantum effects A and B(set-membership sign)E(H). The problem has been studied in different contexts by Kadison, Gudder, Moreland, and Ando. In this Note, using the method of the spectral theory of operators, we give a affirmative answer of a conjecture of [S. Gudder, J. Math. Phys. 37, 2637-2642 (1996)]. In addition, some properties of generalized infimum A intersection B were considered
The Hilbert Series of the One Instanton Moduli Space
Benvenuti, Sergio; Mekareeya, Noppadol; 10.1007
2010-01-01
The moduli space of k G-instantons on R^4 for a classical gauge group G is known to be given by the Higgs branch of a supersymmetric gauge theory that lives on Dp branes probing D(p + 4) branes in Type II theories. For p = 3, these (3 + 1) dimensional gauge theories have N = 2 supersymmetry and can be represented by quiver diagrams. The F and D term equations coincide with the ADHM construction. The Hilbert series of the moduli spaces of one instanton for classical gauge groups is easy to compute and turns out to take a particularly simple form which is previously unknown. This allows for a G invariant character expansion and hence easily generalisable for exceptional gauge groups, where an ADHM construction is not known. The conjectures for exceptional groups are further checked using some new techniques like sewing relations in Hilbert Series. This is applied to Argyres-Seiberg dualities.
A Hilbert space structure on Banach algebras
International Nuclear Information System (INIS)
Mohammad, N.; Thaheem, A.B.
1988-08-01
In this note we define an inner product on ''reduced'' Banach *-algebras via a measure on the set of positive functionals. It is shown here that the resultant inner product space is a topological algebra and also a completeness condition is obtained. (author). 9 refs
Stability for trajectories of periodic evolution families in Hilbert spaces
Directory of Open Access Journals (Sweden)
Dorel Barbu
2014-01-01
Full Text Available Let $q$ be a positive real number and let $A(\\cdot$ be a $q$-periodic linear operator valued function on a complex Hilbert space $H$, and let $D$ be a dense linear subspace of $H$. Let $\\mathcal{U}=\\{U(t, s: t\\ge s\\ge 0\\}$ be the evolution family generated by the family $\\{A(t\\}$. We prove that if the solution of the well-posed inhomogeneous Cauchy Problem $$\\displaylines{ \\dot{u}(t = A(tu(t+e^{i\\mu t}y, \\quad t>0, \\cr u(0 = 0, }$$ is bounded on ${\\mathbb{R}}_+$, for every $y\\in D$, and every $\\mu\\in\\mathbb{R}$, by the positive constant $K\\|y\\|$, $K$ being an absolute constant, and if, in addition, for some $x\\in D$, the trajectory $U(\\cdot, 0x$ satisfies a Lipschitz condition on the interval $(0, q$, then $$ \\sup_{z\\in \\mathbb{C}, |z|=1}\\sup_{n\\in\\mathbb{Z}_+} \\|\\sum_{k=0}^nz^kU(q, 0^kx\\|:=N(x<\\infty. $$ The latter discrete boundedness condition has a lot of consequences concerning the stability of solutions of the abstract nonautonomous system $\\dot u(t=A(tu(t$. To our knowledge, these results are new. In the special case, when $D=H$ and for every $x\\in H $, the map $U(\\cdot, 0x$ satisfies a Lipschitz condition on the interval $(0, q$, the evolution family $\\mathcal{U}$ is uniformly exponentially stable. In the autonomous case, (i.e. when $U(t, s=U(t-s, 0$ for every pair $(t, s$ with $t\\ge s\\ge 0$, the latter assumption is too restrictive. More exactly, in this case, the semigroup $\\mathbf{T}:=\\{U(t, 0\\}_{t\\ge 0}$, is uniformly continuous.
Moretti, Valter; Oppio, Marco
As earlier conjectured by several authors and much later established by Solèr (relying on partial results by Piron, Maeda-Maeda and other authors), from the lattice theory point of view, Quantum Mechanics may be formulated in real, complex or quaternionic Hilbert spaces only. Stückelberg provided some physical, but not mathematically rigorous, reasons for ruling out the real Hilbert space formulation, assuming that any formulation should encompass a statement of Heisenberg principle. Focusing on this issue from another — in our opinion, deeper — viewpoint, we argue that there is a general fundamental reason why elementary quantum systems are not described in real Hilbert spaces. It is their basic symmetry group. In the first part of the paper, we consider an elementary relativistic system within Wigner’s approach defined as a locally-faithful irreducible strongly-continuous unitary representation of the Poincaré group in a real Hilbert space. We prove that, if the squared-mass operator is non-negative, the system admits a natural, Poincaré invariant and unique up to sign, complex structure which commutes with the whole algebra of observables generated by the representation itself. This complex structure leads to a physically equivalent reformulation of the theory in a complex Hilbert space. Within this complex formulation, differently from what happens in the real one, all selfadjoint operators represent observables in accordance with Solèr’s thesis, and the standard quantum version of Noether theorem may be formulated. In the second part of this work, we focus on the physical hypotheses adopted to define a quantum elementary relativistic system relaxing them on the one hand, and making our model physically more general on the other hand. We use a physically more accurate notion of irreducibility regarding the algebra of observables only, we describe the symmetries in terms of automorphisms of the restricted lattice of elementary propositions of the
Aveiro method in reproducing kernel Hilbert spaces under complete dictionary
Mai, Weixiong; Qian, Tao
2017-12-01
Aveiro Method is a sparse representation method in reproducing kernel Hilbert spaces (RKHS) that gives orthogonal projections in linear combinations of reproducing kernels over uniqueness sets. It, however, suffers from determination of uniqueness sets in the underlying RKHS. In fact, in general spaces, uniqueness sets are not easy to be identified, let alone the convergence speed aspect with Aveiro Method. To avoid those difficulties we propose an anew Aveiro Method based on a dictionary and the matching pursuit idea. What we do, in fact, are more: The new Aveiro method will be in relation to the recently proposed, the so called Pre-Orthogonal Greedy Algorithm (P-OGA) involving completion of a given dictionary. The new method is called Aveiro Method Under Complete Dictionary (AMUCD). The complete dictionary consists of all directional derivatives of the underlying reproducing kernels. We show that, under the boundary vanishing condition, bring available for the classical Hardy and Paley-Wiener spaces, the complete dictionary enables an efficient expansion of any given element in the Hilbert space. The proposed method reveals new and advanced aspects in both the Aveiro Method and the greedy algorithm.
Three-Hilbert-Space Formulation of Quantum Mechanics
Czech Academy of Sciences Publication Activity Database
Znojil, Miloslav
2009-01-01
Roč. 5, - (2009), 001/1-001/19 ISSN 1815-0659. [7th Workshop on Quantum Physics with Non-Hermitian Operators. Benasque, 29.06.2007-11.07.2007] R&D Projects: GA ČR GA202/07/1307; GA MŠk LC06002 Institutional research plan: CEZ:AV0Z10480505 Keywords : formulation of Quantum Mechanics * cryptohermitian operators of observables * triplet of the representations of the Hilbert space of states Subject RIV: BE - Theoretical Physics Impact factor: 0.789, year: 2009
Perturbation for Frames for a Subspace of a Hilbert Space
DEFF Research Database (Denmark)
Christensen, Ole; deFlicht, C.; Lennard, C.
1997-01-01
We extend a classical result stating that a sufficiently small perturbation$\\{ g_i \\}$ of a Riesz sequence $\\{ f_i \\}$ in a Hilbert space $H$ is again a Riesz sequence. It turns out that the analog result for a frame does not holdunless the frame is complete. However, we are able to prove a very...... similarresult for frames in the case where the gap between the subspaces$\\overline{span} \\{f_i \\}$ and $\\overline{span} \\{ g_i \\}$ is small enough. We give a geometric interpretation of the result....
Real analysis measure theory, integration, and Hilbert spaces
Stein, Elias M
2005-01-01
Real Analysis is the third volume in the Princeton Lectures in Analysis, a series of four textbooks that aim to present, in an integrated manner, the core areas of analysis. Here the focus is on the development of measure and integration theory, differentiation and integration, Hilbert spaces, and Hausdorff measure and fractals. This book reflects the objective of the series as a whole: to make plain the organic unity that exists between the various parts of the subject, and to illustrate the wide applicability of ideas of analysis to other fields of mathematics and science. After
Geometry of quantum dynamics in infinite-dimensional Hilbert space
Grabowski, Janusz; Kuś, Marek; Marmo, Giuseppe; Shulman, Tatiana
2018-04-01
We develop a geometric approach to quantum mechanics based on the concept of the Tulczyjew triple. Our approach is genuinely infinite-dimensional, i.e. we do not restrict considerations to finite-dimensional Hilbert spaces, contrary to many other works on the geometry of quantum mechanics, and include a Lagrangian formalism in which self-adjoint (Schrödinger) operators are obtained as Lagrangian submanifolds associated with the Lagrangian. As a byproduct we also obtain results concerning coadjoint orbits of the unitary group in infinite dimensions, embedding of pure states in the unitary group, and self-adjoint extensions of symmetric relations.
Application of Hilbert space decomposition to acoustical inverse problems
Lehman, Sean K.
2003-04-01
In a recently developed theory, the forward integral acoustic scattering operator is cast into the formalism of a Hilbert space operator which projects the continuous space scattering object into the discrete measurement space. By determining the singular value decomposition (SVD) of the forward scattering operator, one obtains optimal, orthonormal bases for each of these spaces in the form of the singular vectors. In formulating the inverse scattering problem, it is best to express the unknown object distribution in terms of an expansion of the singular vectors. Using this expansion, the best reconstruction, in a LMS sense, can be obtained from measured scattered field data. We present reconstruction results using this new theory. [Work performed under the auspices of the U.S. Department of Energy by University of California Lawrence Livermore National Laboratory under Contract No. W-7405-Eng-48.
The Hilbert space of the open bosonic string
International Nuclear Information System (INIS)
Nilsson, M.
1988-01-01
For a bosonic particle we know that the Hilbert space comes from the quantized constraints. The mass shell condition, p μ p μ = - m 2 becomes the Klein-Gordon equation after quantization. Thus the constraints lead to a field equation defined on spacetime. For a bosonic string the constraints will be functional equations after quantization. Using the mode expansion we solve for the dependence of the Fourier components with mode number greater than zero. The zero mode is the 'translational' mode and can thus be identified with spacetime. With mode expansion and the standard unification of constraints we arrive at the Virasoro conditions. Here we consider the Virasoro operators as a sum of differential operators. Thus the Virasoro conditions are here a set of differential equations. Discussing the properties of the solutions to these equations we show that the Virasoro conditions can be reduced to a set of field equations for the spacetime mode. We derive all the field equations thus we reduce the Hilbert space of the bosonic string to that of a field theory defined on spacetime. Thus we arrive at a string field theory. Our approach is close to the approach of the CERN group. We show that the field equations only relate fields of the same mass. From the field equations we also find the critical dimension, D=26, and the value of the intercept. (author)
Convex analysis and monotone operator theory in Hilbert spaces
Bauschke, Heinz H
2017-01-01
This reference text, now in its second edition, offers a modern unifying presentation of three basic areas of nonlinear analysis: convex analysis, monotone operator theory, and the fixed point theory of nonexpansive operators. Taking a unique comprehensive approach, the theory is developed from the ground up, with the rich connections and interactions between the areas as the central focus, and it is illustrated by a large number of examples. The Hilbert space setting of the material offers a wide range of applications while avoiding the technical difficulties of general Banach spaces. The authors have also drawn upon recent advances and modern tools to simplify the proofs of key results making the book more accessible to a broader range of scholars and users. Combining a strong emphasis on applications with exceptionally lucid writing and an abundance of exercises, this text is of great value to a large audience including pure and applied mathematicians as well as researchers in engineering, data science, ma...
Construction and coupling of frames in Hilbert spaces with W-metrics
Directory of Open Access Journals (Sweden)
German Escobar
2016-05-01
Full Text Available A definition of frames unitarily equivalent in Hilbert spaces with W-metric is stated, and a characterization is given in terms of their respective analysis operators. From a Hilbert space with a frame we construct a Hilbert space with W-metric and a frame unitarily equivalent to the given one. Finally, we prove that the coupling of two frames is a frame. Resumen. Se definen marcos unitariamente equivalentes en espacios de Hilbert con W-métricas, y se da una caracterización de ellos comparando sus respectivos operadores de análisis. A partir de un espacio de Hilbert con un marco se construye un espacio de Hilbert con W-métrica y un marco unitariamente equivalente al dado. Finalmente, se muestra que el acoplamiento de dos marcos es un marco.
Hamiltonian and physical Hilbert space in polymer quantum mechanics
International Nuclear Information System (INIS)
Corichi, Alejandro; Vukasinac, Tatjana; Zapata, Jose A
2007-01-01
In this paper, a version of polymer quantum mechanics, which is inspired by loop quantum gravity, is considered and shown to be equivalent, in a precise sense, to the standard, experimentally tested Schroedinger quantum mechanics. The kinematical cornerstone of our framework is the so-called polymer representation of the Heisenberg-Weyl (HW) algebra, which is the starting point of the construction. The dynamics is constructed as a continuum limit of effective theories characterized by a scale, and requires a renormalization of the inner product. The result is a physical Hilbert space in which the continuum Hamiltonian can be represented and that is unitarily equivalent to the Schroedinger representation of quantum mechanics. As a concrete implementation of our formalism, the simple harmonic oscillator is fully developed
Galerkin approximations of nonlinear optimal control problems in Hilbert spaces
Directory of Open Access Journals (Sweden)
Mickael D. Chekroun
2017-07-01
Full Text Available Nonlinear optimal control problems in Hilbert spaces are considered for which we derive approximation theorems for Galerkin approximations. Approximation theorems are available in the literature. The originality of our approach relies on the identification of a set of natural assumptions that allows us to deal with a broad class of nonlinear evolution equations and cost functionals for which we derive convergence of the value functions associated with the optimal control problem of the Galerkin approximations. This convergence result holds for a broad class of nonlinear control strategies as well. In particular, we show that the framework applies to the optimal control of semilinear heat equations posed on a general compact manifold without boundary. The framework is then shown to apply to geoengineering and mitigation of greenhouse gas emissions formulated here in terms of optimal control of energy balance climate models posed on the sphere $\\mathbb{S}^2$.
Directory of Open Access Journals (Sweden)
Mourad Kerboua
2014-12-01
Full Text Available We introduce a new notion called fractional stochastic nonlocal condition, and then we study approximate controllability of class of fractional stochastic nonlinear differential equations of Sobolev type in Hilbert spaces. We use Hölder's inequality, fixed point technique, fractional calculus, stochastic analysis and methods adopted directly from deterministic control problems for the main results. A new set of sufficient conditions is formulated and proved for the fractional stochastic control system to be approximately controllable. An example is given to illustrate the abstract results.
Frames and bases in tensor products of Hilbert spaces and Hilbert C ...
Indian Academy of Sciences (India)
Faculty of Mathematical Sciences and Computer Engineering, University for Teacher. Education, 599 ... tensor product of frames (orthonormal bases) for E and F produce frames (orthonormal bases) for Hilbert A ... concept. Frames are used in signal processing, image processing, data compression, sam- pling theory ...
Lipschitz-Type and Bloch-Type Spaces of Pluriharmonic Mappings in a Hilbert Space
Directory of Open Access Journals (Sweden)
Yong Liu
2017-01-01
Full Text Available We investigate some properties of pluriharmonic mappings in an infinite dimensional complex Hilbert space. Several characterizations for pluriharmonic mappings to be in Lipschitz-type and Bloch-type spaces are given, which are generalizations of the corresponding known ones for holomorphic functions with several complex variables.
Chajda, Ivan; Länger, Helmut
2013-06-01
We generalize the concept of a space of numerical events in such a way that this generalization corresponds to arbitrary orthomodular posets whereas spaces of numerical events correspond to orthomodular posets having a full set of states. Moreover, we show that there is a natural one-to-one correspondence between orthomodular posets and certain posets with sectionally antitone involutions. Finally, we characterize orthomodular lattices among orthomodular posets.
Continuous Slice Functional Calculus in Quaternionic Hilbert Spaces
Ghiloni, Riccardo; Moretti, Valter; Perotti, Alessandro
2013-04-01
The aim of this work is to define a continuous functional calculus in quaternionic Hilbert spaces, starting from basic issues regarding the notion of spherical spectrum of a normal operator. As properties of the spherical spectrum suggest, the class of continuous functions to consider in this setting is the one of slice quaternionic functions. Slice functions generalize the concept of slice regular function, which comprises power series with quaternionic coefficients on one side and that can be seen as an effective generalization to quaternions of holomorphic functions of one complex variable. The notion of slice function allows to introduce suitable classes of real, complex and quaternionic C*-algebras and to define, on each of these C*-algebras, a functional calculus for quaternionic normal operators. In particular, we establish several versions of the spectral map theorem. Some of the results are proved also for unbounded operators. However, the mentioned continuous functional calculi are defined only for bounded normal operators. Some comments on the physical significance of our work are included.
Characterizing sequential isomorphisms on Hilbert-space effect algebras
International Nuclear Information System (INIS)
Hou Jinchuan; He Kan; Qi Xiaofei
2010-01-01
Let * be any sequential product on the Hilbert-space effect algebra E(H) with dim H≥2, and Φ:E(H)→E(H) be a bijective map. We show that if Φ satisfies Φ(A*B) = Φ(A)*Φ(B) for A,B element of E(H), then there is either a unitary or an anti-unitary operator U such that Φ(A) = UAU† for every A element of E(H). Let g:[0,1]→{λ|λ element of C, |λ|=0 or 1} be a Borel function satisfying g(0) = 0, g(1) = 1 and let us define a binary operation lozenge g on E(H) by A lozenge g B = A 1/2 g(A)Bg(A)†A 1/2 , where T† denotes the conjugate of the operator T. We also show that a bijective map Φ:E(H)→E(H) satisfies Φ(A lozenge g B) = Φ(A) lozenge g Φ(B) for A,B element of E(H) if and only if there is either a unitary or an anti-unitary operator U such that Φ(A) = UAU† for every A element of E(H).
States in the Hilbert space formulation and in the phase space formulation of quantum mechanics
International Nuclear Information System (INIS)
Tosiek, J.; Brzykcy, P.
2013-01-01
We consider the problem of testing whether a given matrix in the Hilbert space formulation of quantum mechanics or a function considered in the phase space formulation of quantum theory represents a quantum state. We propose several practical criteria for recognising states in these two versions of quantum physics. After minor modifications, they can be applied to check positivity of any operators acting in a Hilbert space or positivity of any functions from an algebra with a ∗-product of Weyl type. -- Highlights: ► Methods of testing whether a given matrix represents a quantum state. ► The Stratonovich–Weyl correspondence on an arbitrary symplectic manifold. ► Criteria for checking whether a function on a symplectic space is a Wigner function
Positive-definite functions and unitary representations of locally compact groups in a Hilbert space
International Nuclear Information System (INIS)
Gali, I.M.; Okb el-Bab, A.S.; Hassan, H.M.
1977-08-01
It is proved that the necessary and sufficient condition for the existence of an integral representation of a group of unitary operators in a Hilbert space is that it is positive-definite and continuous in some topology
Directory of Open Access Journals (Sweden)
Henderson J
2005-01-01
Full Text Available The well-known Krasnoselskii twin fixed point theorem is used to investigate the existence of mild solutions for first- and second-order impulsive semilinear functional and neutral functional differential equations in Hilbert spaces.
On the minimizers of calculus of variations problems in Hilbert spaces
Gomes, Diogo A.
2014-01-19
The objective of this paper is to discuss existence, uniqueness and regularity issues of minimizers of one dimensional calculus of variations problem in Hilbert spaces. © 2014 Springer-Verlag Berlin Heidelberg.
Compact orbit spaces in Hilbert spaces and limits of edge-colouring models
Regts, G.; Schrijver, A.
2016-01-01
Let G be a group of orthogonal transformations of a real Hilbert space H. Let R and W be bounded G-stable subsets of H. Let ‖.‖R‖.‖R be the seminorm on H defined by ‖x‖R:=supr∈R|〈r,x〉|‖x‖R:=supr∈R|〈r,x〉| for x∈Hx∈H. We show that if W is weakly compact and the orbit space Rk/GRk/G is compact for each
Oscillatory integrals on Hilbert spaces and Schroedinger equation with magnetic fields
International Nuclear Information System (INIS)
Albeverio, S.; Brzezniak, Z.
1994-01-01
We extend the theory of oscillatory integrals on Hilbert spaces (the mathematical version of ''Feynman path integrals'') to cover more general integrable functions, preserving the property of the integrals to have converging finite dimensional approximations. We give an application to the representation of solutions of the time dependent Schroedinger equation with a scalar and a magnetic potential by oscillatory integrals on Hilbert spaces. A relation with Ramer's functional in the corresponding probabilistic setting is found. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Neiman, Yakov, E-mail: yashula@gmail.co [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel)
2009-12-21
We argue that the holographic principle may be hinted at already from low-energy considerations, assuming diffeomorphism invariance, quantum mechanics and Minkowski-like causality. We consider the states of finite spacelike hypersurfaces in a diffeomorphism-invariant QFT. A low-energy regularization is assumed. We note a natural dependence of the Hilbert space on a codimension-2 boundary surface. The Hilbert product is defined dynamically, in terms of transition amplitudes which are described by a path integral. We show that a canonical basis is incompatible with these assumptions, which opens the possibility for a smaller Hilbert-space dimension than canonically expected. We argue further that this dimension may decrease with surface area at constant volume, hinting at holographic area proportionality. We draw comparisons with other approaches and setups, and propose an interpretation for the non-holographic space of graviton states at asymptotically Minkowski null infinity.
SU(2){sub q} in a Hilbert space of analytic functions
Energy Technology Data Exchange (ETDEWEB)
Codriansky, S. [Instituto Pedagogico de Caracas (Venezuela)
1992-06-01
The algebra SU(2){sub q} is realized in a Hilbert space H{sub q}{sup 2} of analytic functions; the starting point is the differential realization of operators that satisfy q-algebra in a Hilbert space H{sub q}. The Weyl realization of SU(2){sub q} is constructed exhibiting the reproducing kernel and the principal vectors; the noncommutativity of the matrix elements of a 2x2 linear representation of SU(2){sub q} is obtained as consistency conditions for coupling j1=j2=1/2 to j=0,1; the derivation of Clebsch-Gordan coefficients is sketched and the q-generalization of the rotation matrices is included. The unitary correspondence of H{sub q} with a Hilbert space of complex functions of a real variable is also studied. The study presented in this paper follows Bargmann`s formalism for the rotation group as closely as possible. 20 refs.
3D Hilbert Space Filling Curves in 3D City Modeling for Faster Spatial Queries
DEFF Research Database (Denmark)
Ujang, Uznir; Antón Castro, Francesc/François; Azri, Suhaibah
2014-01-01
The advantages of three dimensional (3D) city models can be seen in various applications including photogrammetry, urban and regional planning, computer games, etc. They expand the visualization and analysis capabilities of Geographic Information Systems on cities, and they can be developed using...... objects. In this research, the authors propose an opponent data constellation technique of space-filling curves (3D Hilbert curves) for 3D city model data representation. Unlike previous methods, that try to project 3D or n-dimensional data down to 2D or 3D using Principal Component Analysis (PCA......) or Hilbert mappings, in this research, they extend the Hilbert space-filling curve to one higher dimension for 3D city model data implementations. The query performance was tested for single object, nearest neighbor and range search queries using a CityGML dataset of 1,000 building blocks and the results...
International Nuclear Information System (INIS)
Blaizot, J.P.
1981-01-01
Using a stationary phase approximation to calculate a functional integral defined on continuous overcomplete sets of vectors of the Hilbert space, one derives a generalized semi-classical quantization condition for periodic trajectories in the Hilbert space. This quantization condition is interpreted in terms of a variational principle. Application to the time dependent Hartree-Fock approximation is presented. (orig.)
Oscillatory Solutions for Second-Order Difference Equations in Hilbert Spaces
Directory of Open Access Journals (Sweden)
González Cristóbal
2007-01-01
Full Text Available We consider the difference equation , , in the context of a Hilbert space. In this setting, we propose a concept of oscillation with respect to a direction and give sufficient conditions so that all its solutions be directionally oscillatory, as well as conditions which guarantee the existence of directionally positive monotone increasing solutions.
An extension of a characterization of the automorphisms of Hilbert space effect algebras
Molnar, Lajos; Kovács, Endre
2003-08-01
The aim of this paper is to show that if an order preserving bijective transformation of the Hilbert space effect algebra also preserves the probability with respect to a fixed pair of mixed states, then it is an ortho-order automorphism. A similar result for the orthomodular lattice of all sharp effects (i.e., projections) is also presented.
Necessary Conditions for Optimal Control of Stochastic Evolution Equations in Hilbert Spaces
Energy Technology Data Exchange (ETDEWEB)
Al-Hussein, Abdul Rahman, E-mail: alhusseinqu@hotmail.com [Qassim University, Department of Mathematics, College of Science (Saudi Arabia)
2011-06-15
We consider a nonlinear stochastic optimal control problem associated with a stochastic evolution equation. This equation is driven by a continuous martingale in a separable Hilbert space and an unbounded time-dependent linear operator.We derive a stochastic maximum principle for this optimal control problem. Our results are achieved by using the adjoint backward stochastic partial differential equation.
Hilbert, Fock and Cantorian spaces in the quantum two-slit gedanken experiment
International Nuclear Information System (INIS)
El Naschie, M.S.
2006-01-01
On the one hand, a rigorous mathematical formulation of quantum mechanics requires the introduction of a Hilbert space and as we move to the second quantization, a Fock space. On the other hand, the Cantorian E-infinity approach to quantum physics was developed largely without any direct reference to the afore mentioned mathematical spaces. In the present work we utilize some novel reinterpretations of basic E (∞) Cantorian spacetime relations in terms of the Hilbert space of quantum mechanics. Proceeding in this way, we gain a better understanding of the physico-mathematical structure of quantum spacetime which is at the heart of the paradoxical and non-intuitive outcome of the famous quantum two-slit gedanken experiment
A simple proof to an extension of a theorem of A. Pazy in Hilbert space
International Nuclear Information System (INIS)
Djafari Rouhani, B.
1990-08-01
We prove that if (x n ) n≥0 is a non expansive sequence in a Hilbert space H, the sequence ( n x n ) n≥1 converges strongly in H to the element of minimum norm in the closed convex hull of the sequence (x n+1 -x n ) n≥0 . This result was previously proved; the proof we give here is even much simpler and can be extended to a Banach space. 29 refs
Hilbert series and moduli spaces of kU(N) vortices
Energy Technology Data Exchange (ETDEWEB)
Hanany, Amihay [Theoretical Physics Group, The Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom); Seong, Rak-Kyeong [School of Physics, Korea Institute for Advanced Study,85 Hoegi-ro, Seoul 130-722 (Korea, Republic of)
2015-02-02
We study the moduli spaces of kU(N) vortices which are realized by the Higgs branch of a U(k) supersymmetric gauge theory. The theory has 4 supercharges and lives on k D1-branes in a N D3- and NS5-brane background. We realize the vortex moduli space as a ℂ{sup ∗} projection of the vortex master space. The Hilbert series is calculated in order to characterize the algebraic structure of the vortex master space and to identify the precise ℂ{sup ∗} projection. As a result, we are able to fully classify the moduli spaces up to 3 vortices.
Free probability induced by electric resistance networks on energy Hilbert spaces
Directory of Open Access Journals (Sweden)
Ilwoo Cho
2011-01-01
Full Text Available We show that a class of countable weighted graphs arising in the study of electric resistance networks (ERNs are naturally associated with groupoids. Starting with a fixed ERN, it is known that there is a canonical energy form and a derived energy Hilbert space \\(H_{\\mathcal{E}}\\. From \\(H_{\\mathcal{E}}\\, one then studies resistance metrics and boundaries of the ERNs. But in earlier research, there does not appear to be a natural algebra of bounded operators acting on \\(H_{\\mathcal{E}}\\. With the use of our ERN-groupoid, we show that \\(H_{\\mathcal{E}}\\ may be derived as a representation Hilbert space of a universal representation of a groupoid algebra \\(\\mathfrak{A}_G\\, and we display other representations. Among our applications, we identify a free structure of \\(\\mathfrak{A}_G\\ in terms of the energy form.
Stieltjes-Tchebycheff moment-theory approach to photoeffect studies in Hilbert space
International Nuclear Information System (INIS)
Langhoff, P.W.
1980-01-01
An outline is given of the so-called Stieltjes-Tchebycheff method for studies of photo cross sections in Hilbert space. This approach, based on recognition of the convergence of spectral moments of the cross section in an L 2 basis, has proved particularly useful in studies of molecular photo-effect, in which case the potentials are noncentral and nonlocal, and electronic wavefunction antisymmetry under permutation must be maintained. Moreover, moment-theory strategy has been adopted recently in nuclear photoeffect studies, and so a description of the Stieltjes-Tchebycheff formalism and related techniques seems appropriate at this time. The general theoretical development is presented. Illustrative applications, including photodissociation of the deutron, photoabsorption in atomic hydrogen and helium, and photodetachment in the hydrogen anion, are given. Polynomial-expansion and continued-fraction summation techniques for obtaining photo cross sections from Hilbert-space calculations are described and are contrasted and compared with the Stieltjes-Tchebycheff approach
Bulk entanglement gravity without a boundary: Towards finding Einstein's equation in Hilbert space
Cao, ChunJun; Carroll, Sean M.
2018-04-01
We consider the emergence from quantum entanglement of spacetime geometry in a bulk region. For certain classes of quantum states in an appropriately factorized Hilbert space, a spatial geometry can be defined by associating areas along codimension-one surfaces with the entanglement entropy between either side. We show how radon transforms can be used to convert these data into a spatial metric. Under a particular set of assumptions, the time evolution of such a state traces out a four-dimensional spacetime geometry, and we argue using a modified version of Jacobson's "entanglement equilibrium" that the geometry should obey Einstein's equation in the weak-field limit. We also discuss how entanglement equilibrium is related to a generalization of the Ryu-Takayanagi formula in more general settings, and how quantum error correction can help specify the emergence map between the full quantum-gravity Hilbert space and the semiclassical limit of quantum fields propagating on a classical spacetime.
Relativistic resonances as non-orthogonal states in Hilbert space
Blum, W
2003-01-01
We analyze the energy-momentum properties of relativistic short-lived particles with the result that they are characterized by two 4-vectors: in addition to the familiar energy-momentum vector (timelike) there is an energy-momentum 'spread vector' (spacelike). The wave functions in space and time for unstable particles are constructed. For the relativistic properties of unstable states we refer to Wigner's method of Poincare group representations that are induced by representations of the space-time translation and rotation groups. If stable particles, unstable particles and resonances are treated as elementary objects that are not fundamentally different one has to take into account that they will not generally be orthogonal to each other in their state space. The scalar product between a stable and an unstable state with otherwise identical properties is calculated in a particular Lorentz frame. The spin of an unstable particle is not infinitely sharp but has a 'spin spread' giving rise to 'spin neighbors'....
The commuting graph of bounded linear operators on a Hilbert space
Czech Academy of Sciences Publication Activity Database
Ambrozie, Calin-Grigore; Bračič, J.; Kuzma, B.; Müller, Vladimír
2013-01-01
Roč. 264, č. 4 (2013), s. 1068-1087 ISSN 0022-1236 R&D Projects: GA ČR GA201/09/0473; GA AV ČR IAA100190903; GA MŠk(CZ) MEB091101 Institutional support: RVO:67985840 Keywords : Hilbert space * operators * commutativity Subject RIV: BA - General Mathematics Impact factor: 1.152, year: 2013 http://www.sciencedirect.com/science/article/pii/S002212361200420X#
INFORMATIVE ENERGY METRIC FOR SIMILARITY MEASURE IN REPRODUCING KERNEL HILBERT SPACES
Directory of Open Access Journals (Sweden)
Songhua Liu
2012-02-01
Full Text Available In this paper, information energy metric (IEM is obtained by similarity computing for high-dimensional samples in a reproducing kernel Hilbert space (RKHS. Firstly, similar/dissimilar subsets and their corresponding informative energy functions are defined. Secondly, IEM is proposed for similarity measure of those subsets, which converts the non-metric distances into metric ones. Finally, applications of this metric is introduced, such as classification problems. Experimental results validate the effectiveness of the proposed method.
Algebras with convergent star products and their representations in Hilbert spaces
International Nuclear Information System (INIS)
Soloviev, M. A.
2013-01-01
We study star product algebras of analytic functions for which the power series defining the products converge absolutely. Such algebras arise naturally in deformation quantization theory and in noncommutative quantum field theory. We consider different star products in a unifying way and present results on the structure and basic properties of these algebras, which are useful for applications. Special attention is given to the Hilbert space representation of the algebras and to the exact description of their corresponding operator algebras
Multiple-Set Split Feasibility Problems for κ-Strictly Pseudononspreading Mapping in Hilbert Spaces
Directory of Open Access Journals (Sweden)
Jing Quan
2013-01-01
Full Text Available The purpose of this paper is to prove some weak and strong convergence theorems for solving the multiple-set split feasibility problems for κ-strictly pseudononspreading mapping in infinite-dimensional Hilbert spaces by using the proposed iterative method. The main results presented in this paper extend and improve the corresponding results of Xu et al. (2006, of Osilike et al. (2011, and of many other authors.
Hilbert-Space-Valued Super-Brownian Motion and Related Evolution Equations
International Nuclear Information System (INIS)
Kallianpur, G.; Sundar, P.
2000-01-01
A stochastic partial differential equation in which the square root of the solution appears as the diffusion coefficient is studied as a particular case of stochastic evolution equations. Weak existence of a solution is proved by the Euler approximation scheme. The super-Brownian motion on [0, 1] is also studied as a Hilbert-space-valued equation. In this set up, weak existence, pathwise uniqueness, and positivity of solutions are obtained in any dimension d
Quantum limits to information about states for finite dimensional Hilbert space
International Nuclear Information System (INIS)
Jones, K.R.W.
1990-01-01
A refined bound for the correlation information of an N-trial apparatus is developed via an heuristic argument for Hilbert spaces of arbitrary finite dimensionality. Conditional upon the proof of an easily motivated inequality it was possible to find the optimal apparatus for large ensemble quantum Inference, thereby solving the asymptotic optimal state determination problem. In this way an alternative inferential uncertainty principle, is defined which is then contrasted with the usual Heisenberg uncertainty principle. 6 refs
Stochastic Integration in Abstract Spaces
Directory of Open Access Journals (Sweden)
J. K. Brooks
2010-01-01
-valued process (∫ called the stochastic integral. The Lebesgue space of these integrable processes is studied and convergence theorems are given. Extensions to general locally convex spaces are presented.
Czech Academy of Sciences Publication Activity Database
Kraus, Michal
2015-01-01
Roč. 143, č. 11 (2015), s. 4835-4844 ISSN 0002-9939 R&D Projects: GA ČR(CZ) GAP201/11/0345 Institutional support: RVO:67985840 Keywords : coarse embedding * uniform embedding * quasi- Banach space * Hilbert space Subject RIV: BA - General Mathematics Impact factor: 0.700, year: 2015 http://www.ams.org/journals/proc/2015-143-11/S0002-9939-2015-12626-3/
Effective realistic interactions for low momentum Hilbert spaces
International Nuclear Information System (INIS)
Weber, Dennis
2012-01-01
Realistic nucleon-nucleon potentials are an essential ingredient of modern microscopic many-body calculations. These potentials can be represented in two different ways: operator representation or matrix element representation. In operator representation the potential is represented by a set of quantum mechanical operators while in matrix element representation it is defined by the matrix elements in a given basis. Many modern potentials are constructed directly in matrix element representation. While the matrix element representation can be calculated from the operator representation, the determination of the operator representation from the matrix elements is more difficult. Some methods to solve the nuclear many-body problem, such as Fermionic Molecular Dynamics (FMD) or the Green's Function Monte Carlo (GFMC) method, however require explicitly the operator representation of the potential, as they do not work in a fixed many-body basis. It is therefore desirable to derive an operator representation also for the interactions given by matrix elements. In this work a method is presented which allows the derivation of an approximate operator representation starting from the momentum space partial wave matrix elements of the interaction. For that purpose an ansatz for the operator representation is chosen. The parameters in the ansatz are determined by a fit to the partial wave matrix elements. Since a perfect reproduction of the matrix elements in general cannot be achieved with a finite number of operators and the quality of the results depends on the choice of the ansatz, the obtained operator representation is tested in nuclear many-body calculations and the results are compared with those from the initial interaction matrix elements. For the calculation of the nucleon-nucleon scattering phase shifts and the deuteron properties a computer code written within this work is used. For larger nuclei the No Core Shell Model (NCSM) and FMD are applied. The described
Quantum computation via local control theory: Direct sum vs. direct product Hilbert spaces
International Nuclear Information System (INIS)
Sklarz, Shlomo E.; Tannor, David J.
2006-01-01
The central objective in any quantum computation is the creation of a desired unitary transformation; the mapping that this unitary transformation produces between the input and output states is identified with the computation. In [S.E. Sklarz, D.J. Tannor, arXiv:quant-ph/0404081 (submitted to PRA) (2004)] it was shown that local control theory can be used to calculate fields that will produce such a desired unitary transformation. In contrast with previous strategies for quantum computing based on optimal control theory, the local control scheme maintains the system within the computational subspace at intermediate times, thereby avoiding unwanted decay processes. In [S.E. Sklarz et al.], the structure of the Hilbert space had a direct sum structure with respect to the computational register and the mediating states. In this paper, we extend the formalism to the important case of a direct product Hilbert space. The final equations for the control algorithm for the two cases are remarkably similar in structure, despite the fact that the derivations are completely different and that in one case the dynamics is in a Hilbert space and in the other case the dynamics is in a Liouville space. As shown in [S.E. Sklarz et al.], the direct sum implementation leads to a computational mechanism based on virtual transitions, and can be viewed as an extension of the principles of Stimulated Raman Adiabatic Passage from state manipulation to evolution operator manipulation. The direct product implementation developed here leads to the intriguing concept of virtual entanglement - computation that exploits second-order transitions that pass through entangled states but that leaves the subsystems nearly separable at all intermediate times. Finally, we speculate on a connection between the algorithm developed here and the concept of decoherence free subspaces
Method of the Determination of Exterior Orientation of Sensors in Hilbert Type Space.
Stępień, Grzegorz
2018-03-17
The following article presents a new isometric transformation algorithm based on the transformation in the newly normed Hilbert type space. The presented method is based on so-called virtual translations, already known in advance, of two relative oblique orthogonal coordinate systems-interior and exterior orientation of sensors-to a common, known in both systems, point. Each of the systems is translated along its axis (the systems have common origins) and at the same time the angular relative orientation of both coordinate systems is constant. The translation of both coordinate systems is defined by the spatial norm determining the length of vectors in the new Hilbert type space. As such, the displacement of two relative oblique orthogonal systems is reduced to zero. This makes it possible to directly calculate the rotation matrix of the sensor. The next and final step is the return translation of the system along an already known track. The method can be used for big rotation angles. The method was verified in laboratory conditions for the test data set and measurement data (field data). The accuracy of the results in the laboratory test is on the level of 10 -6 of the input data. This confirmed the correctness of the assumed calculation method. The method is a further development of the author's 2017 Total Free Station (TFS) transformation to several centroids in Hilbert type space. This is the reason why the method is called Multi-Centroid Isometric Transformation-MCIT. MCIT is very fast and enables, by reducing to zero the translation of two relative oblique orthogonal coordinate systems, direct calculation of the exterior orientation of the sensors.
Method of the Determination of Exterior Orientation of Sensors in Hilbert Type Space
Directory of Open Access Journals (Sweden)
Grzegorz Stępień
2018-03-01
Full Text Available The following article presents a new isometric transformation algorithm based on the transformation in the newly normed Hilbert type space. The presented method is based on so-called virtual translations, already known in advance, of two relative oblique orthogonal coordinate systems—interior and exterior orientation of sensors—to a common, known in both systems, point. Each of the systems is translated along its axis (the systems have common origins and at the same time the angular relative orientation of both coordinate systems is constant. The translation of both coordinate systems is defined by the spatial norm determining the length of vectors in the new Hilbert type space. As such, the displacement of two relative oblique orthogonal systems is reduced to zero. This makes it possible to directly calculate the rotation matrix of the sensor. The next and final step is the return translation of the system along an already known track. The method can be used for big rotation angles. The method was verified in laboratory conditions for the test data set and measurement data (field data. The accuracy of the results in the laboratory test is on the level of 10−6 of the input data. This confirmed the correctness of the assumed calculation method. The method is a further development of the author’s 2017 Total Free Station (TFS transformation to several centroids in Hilbert type space. This is the reason why the method is called Multi-Centroid Isometric Transformation—MCIT. MCIT is very fast and enables, by reducing to zero the translation of two relative oblique orthogonal coordinate systems, direct calculation of the exterior orientation of the sensors.
Graph Subsumption in Abstract State Space Exploration
Zambon, Eduardo; Rensink, Arend; Wijs, A.; Bosnacki, D.; Edelkamp, S.
In this paper we present the extension of an existing method for abstract graph-based state space exploration, called neighbourhood abstraction, with a reduction technique based on subsumption. Basically, one abstract state subsumes another when it covers more concrete states; in such a case, the
Classical and quantum contents of solvable game theory on Hilbert space
International Nuclear Information System (INIS)
Cheon, Taksu; Tsutsui, Izumi
2006-01-01
A simple and general formulation of the quantum game theory is presented, accommodating all possible strategies in the Hilbert space for the first time. The theory is solvable for the two strategy quantum game, which is shown to be equivalent to a family of classical games supplemented by quantum interference. Our formulation gives a clear perspective to understand why and how quantum strategies outmaneuver classical strategies. It also reveals novel aspects of quantum games such as the stone-scissor-paper phase sub-game and the fluctuation-induced moderation
Construction of rigged Hilbert spaces to describe resonances and virtual states
International Nuclear Information System (INIS)
Gadella, M.
1983-01-01
In the present communication we present a mathematical formalism for the description of resonances and virtual states. We start by constructing rigged Hilbert spaces of Hardy class functions restricted to the positive half of the real line. Then resonances and virtual states can be written as generalized eigenvectors of the total Hamiltonian. We also define time evolution on functionals. We see that the time evolution group U(t) splits into two semigroups, one for t > 0 and the other for t < 0, hence showing the irreversibility of the decaying process
Minimal sufficient positive-operator valued measure on a separable Hilbert space
Energy Technology Data Exchange (ETDEWEB)
Kuramochi, Yui, E-mail: kuramochi.yui.22c@st.kyoto-u.ac.jp [Department of Nuclear Engineering, Kyoto University, 6158540 Kyoto (Japan)
2015-10-15
We introduce a concept of a minimal sufficient positive-operator valued measure (POVM), which is the least redundant POVM among the POVMs that have the equivalent information about the measured quantum system. Assuming the system Hilbert space to be separable, we show that for a given POVM, a sufficient statistic called a Lehmann-Scheffé-Bahadur statistic induces a minimal sufficient POVM. We also show that every POVM has an equivalent minimal sufficient POVM and that such a minimal sufficient POVM is unique up to relabeling neglecting null sets. We apply these results to discrete POVMs and information conservation conditions proposed by the author.
An Hilbert space approach for a class of arbitrage free implied volatilities models
Brace, A.; Fabbri, G.; Goldys, B.
2007-01-01
We present an Hilbert space formulation for a set of implied volatility models introduced in \\cite{BraceGoldys01} in which the authors studied conditions for a family of European call options, varying the maturing time and the strike price $T$ an $K$, to be arbitrage free. The arbitrage free conditions give a system of stochastic PDEs for the evolution of the implied volatility surface ${\\hat\\sigma}_t(T,K)$. We will focus on the family obtained fixing a strike $K$ and varying $T$. In order to...
Directory of Open Access Journals (Sweden)
Sedigheh Farzaneh Javan
2017-01-01
Full Text Available A new approach based on the Reproducing Kernel Hilbert Space Method is proposed to approximate the solution of the second-kind nonlinear integral equations. In this case, the Gram-Schmidt process is substituted by another process so that a satisfactory result is obtained. In this method, the solution is expressed in the form of a series. Furthermore, the convergence of the proposed technique is proved. In order to illustrate the effectiveness and efficiency of the method, four sample integral equations arising in electromagnetics are solved via the given algorithm.
A fast nonstationary iterative method with convex penalty for inverse problems in Hilbert spaces
Jin, Qinian; Lu, Xiliang
2014-04-01
In this paper we consider the computation of approximate solutions for inverse problems in Hilbert spaces. In order to capture the special feature of solutions, non-smooth convex functions are introduced as penalty terms. By exploiting the Hilbert space structure of the underlying problems, we propose a fast iterative regularization method which reduces to the classical nonstationary iterated Tikhonov regularization when the penalty term is chosen to be the square of norm. Each iteration of the method consists of two steps: the first step involves only the operator from the problem while the second step involves only the penalty term. This splitting character has the advantage of making the computation efficient. In case the data is corrupted by noise, a stopping rule is proposed to terminate the method and the corresponding regularization property is established. Finally, we test the performance of the method by reporting various numerical simulations, including the image deblurring, the determination of source term in Poisson equation, and the de-autoconvolution problem.
A fast nonstationary iterative method with convex penalty for inverse problems in Hilbert spaces
International Nuclear Information System (INIS)
Jin, Qinian; Lu, Xiliang
2014-01-01
In this paper we consider the computation of approximate solutions for inverse problems in Hilbert spaces. In order to capture the special feature of solutions, non-smooth convex functions are introduced as penalty terms. By exploiting the Hilbert space structure of the underlying problems, we propose a fast iterative regularization method which reduces to the classical nonstationary iterated Tikhonov regularization when the penalty term is chosen to be the square of norm. Each iteration of the method consists of two steps: the first step involves only the operator from the problem while the second step involves only the penalty term. This splitting character has the advantage of making the computation efficient. In case the data is corrupted by noise, a stopping rule is proposed to terminate the method and the corresponding regularization property is established. Finally, we test the performance of the method by reporting various numerical simulations, including the image deblurring, the determination of source term in Poisson equation, and the de-autoconvolution problem. (paper)
Some New Characterizations and g-Minimality and Stability of g-Bases in the Hilbert Spaces
Directory of Open Access Journals (Sweden)
Xunxiang Guo
2013-01-01
Full Text Available The concept of g-basis in the Hilbert spaces is introduced by Guo (2012 who generalizes the Schauder basis in the Hilbert spaces. g-basis plays the similar role in g-frame theory to that the Schauder basis plays in frame theory. In this paper, we establish some important properties of g-bases in the Hilbert spaces. In particular, we obtain a simple condition under which some important properties established in Guo (2012 are still true. With these conditions, we also establish some new interesting properties of g-bases which are related to g-minimality. Finally, we obtain a perturbation result about g-bases.
Hilbert Series for Moduli Spaces of Instantons on C^2/Z_n
Dey, Anindya; Mekareeya, Noppadol; Rodríguez-Gómez, Diego; Seong, Rak-Kyeong
2014-01-01
We study chiral gauge-invariant operators on moduli spaces of G instantons for any classical group G on A-type ALE spaces using Hilbert Series (HS). Moduli spaces of instantons on an ALE space can be realized as Higgs branches of certain quiver gauge theories which appear as world-volume theories on Dp branes in a Dp-D(p+4) system with the D(p+4) branes (with or without O(p+4) planes) wrapping the ALE space. We study in detail a list of quiver gauge theories which are related to G-instantons of arbitrary ranks and instanton numbers on a generic A_{n-1} ALE space and discuss the corresponding brane configurations. For a large class of theories, we explicitly compute the Higgs branch HS which reveals various algebraic/geometric aspects of the moduli space such as the dimension of the space, generators of the moduli space and relations connecting them. In a large number of examples involving lower rank instantons, we demonstrate that HS for equivalent instantons of isomorphic gauge groups but very different quiv...
Fano, Guido
2017-01-01
This book is designed to make accessible to nonspecialists the still evolving concepts of quantum mechanics and the terminology in which these are expressed. The opening chapters summarize elementary concepts of twentieth century quantum mechanics and describe the mathematical methods employed in the field, with clear explanation of, for example, Hilbert space, complex variables, complex vector spaces and Dirac notation, and the Heisenberg uncertainty principle. After detailed discussion of the Schrödinger equation, subsequent chapters focus on isotropic vectors, used to construct spinors, and on conceptual problems associated with measurement, superposition, and decoherence in quantum systems. Here, due attention is paid to Bell’s inequality and the possible existence of hidden variables. Finally, progression toward quantum computation is examined in detail: if quantum computers can be made practicable, enormous enhancements in computing power, artificial intelligence, and secure communication will result...
The physical boundary Hilbert space and volume operator in the Lorentzian new spin-foam theory
International Nuclear Information System (INIS)
Ding You; Rovelli, Carlo
2010-01-01
A covariant spin-foam formulation of quantum gravity has been recently developed, characterized by a kinematics which appears to match well the one of canonical loop quantum gravity. In this paper we reconsider the implementation of the constraints that defines the model. We define in a simple way the boundary Hilbert space of the theory, introducing a slight modification of the embedding of the SU(2) representations into the SL(2,C) ones. We then show directly that all constraints vanish on this space in a weak sense. The vanishing is exact (and not just in the large quantum number limit). We also generalize the definition of the volume operator in the spin-foam model to the Lorentzian signature and show that it matches the one of loop quantum gravity, as in the Euclidean case.
International Nuclear Information System (INIS)
Khrennikov, A.
2005-01-01
We constructed the representation of contextual probabilistic dynamics in the complex Hilbert space. Thus dynamics of the wave function can be considered as Hilbert space projection of realistic dynamics in a pre space. The basic condition for representing the pre space-dynamics is the law of statistical conservation of energy-conservation of probabilities. The construction of the dynamical representation is an important step in the development of contextual statistical viewpoint of quantum processes. But the contextual statistical model is essentially more general than the quantum one. Therefore in general the Hilbert space projection of the pre space dynamics can be nonlinear and even irreversible (but it is always unitary). There were found conditions of linearity and reversibility of the Hilbert space dynamical projection. We also found conditions for the conventional Schrodinger dynamics (including time-dependent Hamiltonians). We remark that in general even the Schrodinger dynamics is based just on the statistical conservation of energy; for individual systems the law of conservation of energy can be violated (at least in our theoretical model)
Pauli graphs when the Hilbert space dimension contains a square: Why the Dedekind psi function?
Energy Technology Data Exchange (ETDEWEB)
Planat, Michel, E-mail: michel.planat@femto-st.fr [Institut FEMTO-ST, CNRS, 32 Avenue de l' Observatoire, F-25044 Besancon (France)
2011-01-28
We study the commutation relations within the Pauli groups built on all decompositions of a given Hilbert space dimension q, containing a square, into its factors. Illustrative low-dimensional examples are the quartit (q = 4) and two-qubit (q = 2{sup 2}) systems, the octit (q = 8), qubit/quartit (q = 2 x 4) and three-qubit (q = 2{sup 3}) systems, and so on. In the single qudit case, e.g. q = 4, 8, 12, ... , one defines a bijection between the {sigma}(q) maximal commuting sets (with {sigma}[q) being the sum of divisors of q) of Pauli observables and the maximal submodules of the modular ring Z{sub q}{sup 2}, that arrange into the projective line P{sub 1}(Z{sub q}) and an independent set of size {sigma}(q) - {psi}(q) (with {psi}(q) being the Dedekind psi function). In the multiple qudit case, e.g. q = 2{sup 2}, 2{sup 3}, 3{sup 2}, ... , the Pauli graphs rely on symplectic polar spaces such as the generalized quadrangles GQ(2, 2) (if q = 2{sup 2}) and GQ(3, 3) (if q = 3{sup 2}). More precisely, in the dimension p{sup n} (p a prime) of the Hilbert space, the observables of the Pauli group (modulo the center) are seen as the elements of the 2n-dimensional vector space over the field F{sub p}. In this space, one makes use of the commutator to define a symplectic polar space W{sub 2n-1}(p) of cardinality {sigma}(p{sup 2n-1}) that encodes the maximal commuting sets of the Pauli group by its totally isotropic subspaces. Building blocks of W{sub 2n-1}(p) are punctured polar spaces (i.e. a observable and all maximum cliques passing to it are removed) of size given by the Dedekind psi function {psi}(p{sup 2n-1}). For multiple qudit mixtures (e.g. qubit/quartit, qubit/octit and so on), one finds multiple copies of polar spaces, punctured polar spaces, hypercube geometries and other intricate structures. Such structures play a role in the science of quantum information.
Parallel magnetic resonance imaging as approximation in a reproducing kernel Hilbert space
International Nuclear Information System (INIS)
Athalye, Vivek; Lustig, Michael; Martin Uecker
2015-01-01
In magnetic resonance imaging data samples are collected in the spatial frequency domain (k-space), typically by time-consuming line-by-line scanning on a Cartesian grid. Scans can be accelerated by simultaneous acquisition of data using multiple receivers (parallel imaging), and by using more efficient non-Cartesian sampling schemes. To understand and design k-space sampling patterns, a theoretical framework is needed to analyze how well arbitrary sampling patterns reconstruct unsampled k-space using receive coil information. As shown here, reconstruction from samples at arbitrary locations can be understood as approximation of vector-valued functions from the acquired samples and formulated using a reproducing kernel Hilbert space with a matrix-valued kernel defined by the spatial sensitivities of the receive coils. This establishes a formal connection between approximation theory and parallel imaging. Theoretical tools from approximation theory can then be used to understand reconstruction in k-space and to extend the analysis of the effects of samples selection beyond the traditional image-domain g-factor noise analysis to both noise amplification and approximation errors in k-space. This is demonstrated with numerical examples. (paper)
Ito, Kazufumi
1987-01-01
The linear quadratic optimal control problem on infinite time interval for linear time-invariant systems defined on Hilbert spaces is considered. The optimal control is given by a feedback form in terms of solution pi to the associated algebraic Riccati equation (ARE). A Ritz type approximation is used to obtain a sequence pi sup N of finite dimensional approximations of the solution to ARE. A sufficient condition that shows pi sup N converges strongly to pi is obtained. Under this condition, a formula is derived which can be used to obtain a rate of convergence of pi sup N to pi. The results of the Galerkin approximation is demonstrated and applied for parabolic systems and the averaging approximation for hereditary differential systems.
Single image super-resolution via an iterative reproducing kernel Hilbert space method.
Deng, Liang-Jian; Guo, Weihong; Huang, Ting-Zhu
2016-11-01
Image super-resolution, a process to enhance image resolution, has important applications in satellite imaging, high definition television, medical imaging, etc. Many existing approaches use multiple low-resolution images to recover one high-resolution image. In this paper, we present an iterative scheme to solve single image super-resolution problems. It recovers a high quality high-resolution image from solely one low-resolution image without using a training data set. We solve the problem from image intensity function estimation perspective and assume the image contains smooth and edge components. We model the smooth components of an image using a thin-plate reproducing kernel Hilbert space (RKHS) and the edges using approximated Heaviside functions. The proposed method is applied to image patches, aiming to reduce computation and storage. Visual and quantitative comparisons with some competitive approaches show the effectiveness of the proposed method.
Blanchard, Philippe
2015-01-01
The second edition of this textbook presents the basic mathematical knowledge and skills that are needed for courses on modern theoretical physics, such as those on quantum mechanics, classical and quantum field theory, and related areas. The authors stress that learning mathematical physics is not a passive process and include numerous detailed proofs, examples, and over 200 exercises, as well as hints linking mathematical concepts and results to the relevant physical concepts and theories. All of the material from the first edition has been updated, and five new chapters have been added on such topics as distributions, Hilbert space operators, and variational methods. The text is divided into three main parts. Part I is a brief introduction to distribution theory, in which elements from the theories of ultradistributions and hyperfunctions are considered in addition to some deeper results for Schwartz distributions, thus providing a comprehensive introduction to the theory of generalized functions. P...
Strong Metrizability for Closed Operators and the Semi-Fredholm Operators between Two Hilbert Spaces
Directory of Open Access Journals (Sweden)
Mohammed Benharrat
2015-08-01
Full Text Available To be able to refine the completion of C(H1, H2, the of set all closed densely defined linear operators between two Hilbert spaces H1 and H2, we define in this paper some new strictly stronger metrics than the gap metric g and we characterize the closure with respect to theses metrics of the subset L(H1, H2 of bounded elements of C(H1, H2. In addition, several operator norm inequalities concerning the equivalence of some metrics on L(H1, H2 are presented. We also establish the semi-Fredholmness and Fredholmness of unbounded in terms of bounded pure contractions.
A Numerical Approximation Framework for the Stochastic Linear Quadratic Regulator on Hilbert Spaces
Energy Technology Data Exchange (ETDEWEB)
Levajković, Tijana, E-mail: tijana.levajkovic@uibk.ac.at, E-mail: t.levajkovic@sf.bg.ac.rs; Mena, Hermann, E-mail: hermann.mena@uibk.ac.at [University of Innsbruck, Department of Mathematics (Austria); Tuffaha, Amjad, E-mail: atufaha@aus.edu [American University of Sharjah, Department of Mathematics (United Arab Emirates)
2017-06-15
We present an approximation framework for computing the solution of the stochastic linear quadratic control problem on Hilbert spaces. We focus on the finite horizon case and the related differential Riccati equations (DREs). Our approximation framework is concerned with the so-called “singular estimate control systems” (Lasiecka in Optimal control problems and Riccati equations for systems with unbounded controls and partially analytic generators: applications to boundary and point control problems, 2004) which model certain coupled systems of parabolic/hyperbolic mixed partial differential equations with boundary or point control. We prove that the solutions of the approximate finite-dimensional DREs converge to the solution of the infinite-dimensional DRE. In addition, we prove that the optimal state and control of the approximate finite-dimensional problem converge to the optimal state and control of the corresponding infinite-dimensional problem.
Construction and coupling of frames in Hilbert spaces with W-metrics
Directory of Open Access Journals (Sweden)
German Escobar
2016-01-01
Full Text Available Se definen marcos unitariamente equivalentes en espacios de Hilbert con W-métricas, y se da una caracterización de ellos comparando sus respectivos operadores de análisis. A partir de un espacio de Hilbert con un marco se construye un espacio de Hilbert con W-métrica y un marco unitariamente equivalente al dado. Finalmente, se muestra que el acoplamiento de dos marcos es un marco.
A note on stability of the integral-differential equation of the hyperbolic type in a Hilbert space
M. Ashyraliyev (Maksat)
2008-01-01
htmlabstractIn this paper, the initial-value problem for integral-differential equation of the hyperbolic type in a Hilbert space H is considered. The unique solvability of this problem is established. The stability estimates for the solution of this problem are obtained. The difference scheme
Hybrid methods for a finite family of G-nonexpansive mappings in Hilbert spaces endowed with graphs
Directory of Open Access Journals (Sweden)
Raweerote Suparatulatorn
2017-08-01
Full Text Available In this paper, we prove a strong convergence theorem for two different hybrid methods by using CQ method for a finite family of G-nonexpansive mappings in a Hilbert space. We give an example and numerical results for supporting our main results and compare the rate of convergence of the two iterative methods.
International Nuclear Information System (INIS)
Gessner, W.; Ernst, V.
1980-01-01
The indefinite metric space O/sub M/ of the covariant form of the quantized Maxwell field M is analyzed in some detail. S/sub M/ contains not only the pre-Hilbert space X 0 of states of transverse photons which occurs in the Gupta--Bleuler formalism of the free M, but a whole rosette of continuously many, isomorphic, complete, pre-Hilbert spaces L/sup q/ disjunct up to the zero element o of S/sub M/. The L/sup q/ are the maximal subspaces of S/sub M/ which allow the usual statistical interpretation. Each L/sup q/ corresponds uniquely to one square integrable, spatial distribution j/sup o/(x) of the total charge Q=0. If M is in any state from L/sup q/, the bare charge j 0 (x) appears to be inseparably dressed by the quantum equivalent of its proper, classical Coulomb field E(x). The vacuum occurs only in the state space L 0 of the free Maxwell field. Each L/sup q/ contains a secondary rosette of continuously many, up to o disjunct, isomorphic Hilbert spaces H/sub g//sup q/ related to different electromagnetic gauges. The space H/sub o//sup q/, which corresponds to the Coulomb gauge within the Lorentz gauge, plays a physically distinguished role in that only it leads to the usual concept of energy. If M is in any state from H/sub g//sup q/, the bare 4-current j 0 (x), j(x), where j(x) is any square integrable, transverse current density in space, is endowed with its proper 4-potential which depends on the chosen gauge, and with its proper, gauge independent, Coulomb--Oersted field E(x), B(x). However, these fields exist only in the sense of quantum mechanical expectation values equipped with the corresponding field fluctuations. So they are basically different from classical electromagnetic fields
On the continuity of the map square root of nonnegative isomorphisms in Hilbert spaces
Directory of Open Access Journals (Sweden)
Jeovanny de Jesus Muentes Acevedo
2015-06-01
Full Text Available Let H be a real (or complex Hilbert space. Every nonnegative operator L ∈ L(H admits a unique nonnegative square root R ∈ L(H, i.e., a nonnegative operator R ∈ L(H such that R2 = L. Let GL+ S (H be the set of nonnegative isomorphisms in L(H. First we will show that GL+ S (H is a convex (real Banach manifold. Denoting by L1/2 the nonnegative square root of L. In [3], Richard Bouldin proves that L1/2 depends continuously on L (this proof is non-trivial. This result has several applications. For example, it is used to find the polar decomposition of a bounded operator. This polar decomposition allows us to determine the positive and negative spectral subespaces of any self-adjoint operator, and moreover, allows us to define the Maslov index. The autor of the paper under review provides an alternative proof (and a little more simplified that L1/2 depends continuously on L, and moreover, he shows that the map is a homeomorphism. Resumen. Sea H un espacio de Hilbert real (o complejo. Todo operador no negativo L ∈ L(H admite una única raíz cuadrada no negativa R ∈ L(H, esto es, un operador no negativo R ∈ L(H tal que R2 = L. Sea GL+ S (H el conjunto de los isomorfismos no negativos en L(H. Primero probaremos que GL+ S (H es una variedad de Banach (real. Denotando como L1/2 la raíz cuadrada no negativa de L, en [3] Richard Bouldin prueba que L1/2 depende continuamente de L (esta prueba es no trivial. Este resultado tiene varias aplicaciones. Por ejemplo, es usado para encontrar la descomposición polar de un operador limitado. Esta descomposición polar nos lleva a determinar los subespacios espectrales positivos y negativos de cualquier operador autoadjunto, y además, lleva a definir el índice de Máslov. El autor de este artículo da una prueba alternativa (y un poco más simplificada de que L1/2 depende continuamente de L, y además, prueba que la aplicación es un homeomorfismo
International Nuclear Information System (INIS)
Bach, A.
1981-01-01
A representation of quantum mechanics in terms of classical probability theory by means of integration in Hilbert space is discussed. This formal hidden-variables representation is analysed in the context of impossibility proofs concerning hidden-variables theories. The structural analogy of this formulation of quantum theory with classical statistical mechanics is used to elucidate the difference between classical mechanics and quantum mechanics. (author)
International Nuclear Information System (INIS)
Gallego-Castillo, Cristobal; Bessa, Ricardo; Cavalcante, Laura; Lopez-Garcia, Oscar
2016-01-01
Wind power probabilistic forecast is being used as input in several decision-making problems, such as stochastic unit commitment, operating reserve setting and electricity market bidding. This work introduces a new on-line quantile regression model based on the Reproducing Kernel Hilbert Space (RKHS) framework. Its application to the field of wind power forecasting involves a discussion on the choice of the bias term of the quantile models, and the consideration of the operational framework in order to mimic real conditions. Benchmark against linear and splines quantile regression models was performed for a real case study during a 18 months period. Model parameter selection was based on k-fold crossvalidation. Results showed a noticeable improvement in terms of calibration, a key criterion for the wind power industry. Modest improvements in terms of Continuous Ranked Probability Score (CRPS) were also observed for prediction horizons between 6 and 20 h ahead. - Highlights: • New online quantile regression model based on the Reproducing Kernel Hilbert Space. • First application to operational probabilistic wind power forecasting. • Modest improvements of CRPS for prediction horizons between 6 and 20 h ahead. • Noticeable improvements in terms of Calibration due to online learning.
International Nuclear Information System (INIS)
Arik, M.
1991-01-01
It is shown that the differential calculus of Wess and Zumino for the quantum hyperplane is intimately related to the q-difference operator acting on the n-dimensional complex space C n . An explicit transformation relates the variables and the q-difference operators on C n to the variables and the quantum derivatives on the quantum hyperplane. For real values of the quantum parameter q, the consideration of the variables and the derivatives as hermitean conjugates yields a quantum deformation of the Bargmann-Segal Hilbert space of analytic functions on C n . Physically such a system can be interpreted as the quantum deformation of the n dimensional harmonic oscillator invariant under the unitary quantum group U q (n) with energy eigenvalues proportional to the basic integers. Finally, a construction of the variables and quantum derivatives on the quantum hyperplane in terms of variables and ordinary derivatives on C n is presented. (orig.)
Directory of Open Access Journals (Sweden)
Quynh Anh NguyenThi
2011-01-01
Full Text Available We introduce a new implicit iteration method for finding a solution for a variational inequality involving Lipschitz continuous and strongly monotone mapping over the set of common fixed points for a finite family of nonexpansive mappings on Hilbert spaces.
Equations Holding in Hilbert Lattices
Mayet, René
2006-07-01
We produce and study several sequences of equations, in the language of orthomodular lattices, which hold in the ortholattice of closed subspaces of any classical Hilbert space, but not in all orthomodular lattices. Most of these equations hold in any orthomodular lattice admitting a strong set of states whose values are in a real Hilbert space. For some of these equations, we give conditions under which they hold in the ortholattice of closed subspaces of a generalised Hilbert space. These conditions are relative to the dimension of the Hilbert space and to the characteristic of its division ring of scalars. In some cases, we show that these equations cannot be deduced from the already known equations, and we study their mutual independence. To conclude, we suggest a new method for obtaining such equations, using the tensorial product.
Directory of Open Access Journals (Sweden)
Kan Li
2018-04-01
Full Text Available This paper presents a novel real-time dynamic framework for quantifying time-series structure in spoken words using spikes. Audio signals are converted into multi-channel spike trains using a biologically-inspired leaky integrate-and-fire (LIF spike generator. These spike trains are mapped into a function space of infinite dimension, i.e., a Reproducing Kernel Hilbert Space (RKHS using point-process kernels, where a state-space model learns the dynamics of the multidimensional spike input using gradient descent learning. This kernelized recurrent system is very parsimonious and achieves the necessary memory depth via feedback of its internal states when trained discriminatively, utilizing the full context of the phoneme sequence. A main advantage of modeling nonlinear dynamics using state-space trajectories in the RKHS is that it imposes no restriction on the relationship between the exogenous input and its internal state. We are free to choose the input representation with an appropriate kernel, and changing the kernel does not impact the system nor the learning algorithm. Moreover, we show that this novel framework can outperform both traditional hidden Markov model (HMM speech processing as well as neuromorphic implementations based on spiking neural network (SNN, yielding accurate and ultra-low power word spotters. As a proof of concept, we demonstrate its capabilities using the benchmark TI-46 digit corpus for isolated-word automatic speech recognition (ASR or keyword spotting. Compared to HMM using Mel-frequency cepstral coefficient (MFCC front-end without time-derivatives, our MFCC-KAARMA offered improved performance. For spike-train front-end, spike-KAARMA also outperformed state-of-the-art SNN solutions. Furthermore, compared to MFCCs, spike trains provided enhanced noise robustness in certain low signal-to-noise ratio (SNR regime.
Coherent states on Hilbert modules
Energy Technology Data Exchange (ETDEWEB)
Ali, S Twareque [Department of Mathematics and Statistics, Concordia University, 1455 De Maisonneuve Blvd West, Montreal, Quebec H3G 1M8 (Canada); Bhattacharyya, T [Department of Mathematics, Indian Institute of Science, Bengaluru 560012, Karnataka (India); Roy, S S, E-mail: stali@math.concordia.ca, E-mail: tirtha@member.ams.org [Department of Mathematics and Statistics, Indian Institute of Science Education and Research, Kolkata, Mohanpur 741252, West Bengal (India)
2011-07-08
We generalize the concept of coherent states, traditionally defined as special families of vectors on Hilbert spaces, to Hilbert modules. We show that Hilbert modules over C*-algebras are the natural settings for a generalization of coherent states defined on Hilbert spaces. We consider those Hilbert C*-modules which have a natural left action from another C*-algebra, say A. The coherent states are well defined in this case and they behave well with respect to the left action by A. Certain classical objects like the Cuntz algebra are related to specific examples of coherent states. Finally we show that coherent states on modules give rise to a completely positive definite kernel between two C*-algebras, in complete analogy to the Hilbert space situation. Related to this, there is a dilation result for positive operator-valued measures, in the sense of Naimark. A number of examples are worked out to illustrate the theory. Some possible physical applications are also mentioned.
Quantum correlations and dynamics from classical random fields valued in complex Hilbert spaces
International Nuclear Information System (INIS)
Khrennikov, Andrei
2010-01-01
One of the crucial differences between mathematical models of classical and quantum mechanics (QM) is the use of the tensor product of the state spaces of subsystems as the state space of the corresponding composite system. (To describe an ensemble of classical composite systems, one uses random variables taking values in the Cartesian product of the state spaces of subsystems.) We show that, nevertheless, it is possible to establish a natural correspondence between the classical and the quantum probabilistic descriptions of composite systems. Quantum averages for composite systems (including entangled) can be represented as averages with respect to classical random fields. It is essentially what Albert Einstein dreamed of. QM is represented as classical statistical mechanics with infinite-dimensional phase space. While the mathematical construction is completely rigorous, its physical interpretation is a complicated problem. We present the basic physical interpretation of prequantum classical statistical field theory in Sec. II. However, this is only the first step toward real physical theory.
The space generated by metric and torsion tensors, derivation of Einstein-Hilbert equation
Directory of Open Access Journals (Sweden)
Николай Иванович Яременко
2014-11-01
Full Text Available This paper is devoted to the derivation of field equations in space with the geometric structure generated by metric and torsion tensors. We also study the geometry of the space are generated jointly and agreed by the metric tensor and the torsion tensor. We showed that in such space the structure of the curvature tensor has special features and for this tensor obtained analog Ricci - Jacobi identity; was evaluated gap that occurs at the transition from the original to the image and vice versa, in the case of an infinitely small contours. We have researched the geodesic lines equation. We introduce the tensor π_αβ which is similar to the second fundamental tensor of hypersurfaces Y^n-1, but the structure of this tensor is substantially different from the case of Riemannian spaces with zero torsion. Then we obtained formulas which characterize the change of vectors in accompanying basis relative to this basis itself in the small. Taking into considerations our results about the structure of such space we derived from the variation principle the general field equations (electromagnetic and gravitational.
Potoček, Václav; Miatto, Filippo M; Mirhosseini, Mohammad; Magaña-Loaiza, Omar S; Liapis, Andreas C; Oi, Daniel K L; Boyd, Robert W; Jeffers, John
2015-10-16
In 1924 David Hilbert conceived a paradoxical tale involving a hotel with an infinite number of rooms to illustrate some aspects of the mathematical notion of "infinity." In continuous-variable quantum mechanics we routinely make use of infinite state spaces: here we show that such a theoretical apparatus can accommodate an analog of Hilbert's hotel paradox. We devise a protocol that, mimicking what happens to the guests of the hotel, maps the amplitudes of an infinite eigenbasis to twice their original quantum number in a coherent and deterministic manner, producing infinitely many unoccupied levels in the process. We demonstrate the feasibility of the protocol by experimentally realizing it on the orbital angular momentum of a paraxial field. This new non-Gaussian operation may be exploited, for example, for enhancing the sensitivity of NOON states, for increasing the capacity of a channel, or for multiplexing multiple channels into a single one.
Inc, Mustafa; Akgül, Ali; Kılıçman, Adem
2013-01-01
The present paper emphasizes Jeffery-Hamel flow: fluid flow between two rigid plane walls, where the angle between them is 2 $\\alpha $ . A new method called the reproducing kernel Hilbert space method (RKHSM) is briefly introduced. The validity of the reproducing kernel method is set by comparing our results with HAM, DTM, and HPM and numerical results for different values of $H$ , $\\alpha $ , and Re. The results show up that the proposed reproducing kernel method can achieve good results in ...
Deng, Bin-Chao; Chen, Tong; Xin, Baogui
2012-01-01
We introduce an iterative method for finding a common element of set of fixed points of nonexpansive mappings, the set of solutions of a finite family of variational inclusion with set-valued maximal monotone mappings and inverse strongly monotone mappings, and the set of solutions of a mixed equilibrium problem in Hilbert spaces. Under suitable conditions, some strong convergence theorems for approximating this common elements are proved. The results presented in the pap...
Homotopy invariance of the Conley index and local Morse homology in Hilbert spaces
Izydorek, Marek; Rot, Thomas O.; Starostka, Maciej; Styborski, Marcin; Vandervorst, Robert C.A.M.
2017-01-01
In this paper we introduce a new compactness condition — Property-(C) — for flows in (not necessary locally compact) metric spaces. For such flows a Conley type theory can be developed. For example (regular) index pairs always exist for Property-(C) flows and a Conley index can be defined. An
International Nuclear Information System (INIS)
Schroer, Bert; FU-Berlin
2012-02-01
Massive quantum matter of prescribed spin permits infinitely many possibilities of covariantization in terms of spinorial (undotted/dotted) pointlike fields, whereas massless nite helicity representations lead to large gap in this spinorial spectrum which for s=1 excludes vector potentials. Since the nonexistence of such pointlike generators is the result of a deep structural clash between modular localization and the Hilbert space setting of QT, there are two ways out: gauge theory which sacrifices the Hilbert space and keeps the pointlike formalism and the use of string like potentials which allows to preserve the Hilbert space. The latter setting contains also string-localized charge-carrying operators whereas the gauge theoretic formulation is limited to point-like generated observables. This description also gives a much better insight into the Higgs mechanism which leads to a revival of the more physical 'Schwinger-Higgs' screening idea. The new formalism is not limited to m=0, s=1, it leads to renormalizable inter- actions in the sense of power-counting for all s in massless representations. The existence of string like vector potentials is preempted by the Aharonov-Bohm effect in QFT; it is well-known that the use of pointlike vector potentials in Stokes theorem would with lead to wrong results. Their use in Maxwell's equations is known to lead to zero Maxwell charge. The role of string-localization in the problem behind the observed invisibility and confinement of gluons and quarks leads to new questions and problems. (author)
Variational Inequalities in Hilbert Spaces with Measures and Optimal Stopping Problems
International Nuclear Information System (INIS)
Barbu, Viorel; Marinelli, Carlo
2008-01-01
We study the existence theory for parabolic variational inequalities in weighted L 2 spaces with respect to excessive measures associated with a transition semigroup. We characterize the value function of optimal stopping problems for finite and infinite dimensional diffusions as a generalized solution of such a variational inequality. The weighted L 2 setting allows us to cover some singular cases, such as optimal stopping for stochastic equations with degenerate diffusion coefficient. As an application of the theory, we consider the pricing of American-style contingent claims. Among others, we treat the cases of assets with stochastic volatility and with path-dependent payoffs
Truncated Hilbert Space Approach for the 1+1D phi^4 Theory
CERN. Geneva
2016-01-01
(an informal seminar, not a regular string seminar) We used the massive analogue of the truncated conformal space approach to study the broken phase of the 1+1 dimensional scalar phi^4 model in finite volume, similarly to the work by S. Rychkov and L. Vitale. In our work, the finite size spectrum was determined numerically using an effective eigensolver routine, which was followed by a simple extrapolation in the cutoff energy. We analyzed both the periodic and antiperiodic sectors. The results were compared with semiclassical and Bethe-Yang results as well as perturbation theory. We obtained the coupling dependence of the infinite volume breather and kink masses for moderate couplings. The results fit well with semiclassics and perturbative estimations, and confirm the conjecture of Mussardo that at most two neutral excitations can exist in the spectrum. We believe that improving our method with the renormalization procedure of Rychkov et al. enables to measure further interesting quantities such as decay ra...
Directory of Open Access Journals (Sweden)
Ali Hadi Abdulwahid
2016-12-01
Full Text Available Nowadays, the use of distributed generation (DG has increased because of benefits such as increased reliability, reduced losses, improvement in the line capacity, and less environmental pollution. The protection of microgrids, which consist of generation sources, is one of the most crucial concerns of basic distribution operators. One of the key issues in this field is the protection of microgrids against permanent and temporary failures by improving the safety and reliability of the network. The traditional method has a number of disadvantages. The reliability and stability of a power system in a microgrid depend to a great extent on the efficiency of the protection scheme. The application of Artificial Intelligence approaches was introduced recently in the protection of distribution networks. The fault detection method depends on differential relay based on Hilbert Space-Based Power (HSBP theory to achieve fastest primary protection. It is backed up by a total harmonic distortion (THD detection method that takes over in case of a failure in the primary method. The backup protection would be completely independent of the main protection. This is rarely attained in practice. This paper proposes a new algorithm to improve protection performance by adaptive network-based fuzzy inference system (ANFIS. The protection can be obtained in a novel way based on this theory. An advantage of this algorithm is that the protection system operates in fewer than two cycles after the occurrence of the fault. Another advantage is that the error detection is not dependent on the selection of threshold values, and all types of internal fault can identify and show that the algorithm operates correctly for all types of faults while preventing unwanted tripping, even if the data were distorted by current transformer (CT saturation or by data mismatches. The simulation results show that the proposed circuit can identify the faulty phase in the microgrid quickly and
Quantum systems with finite Hilbert space: Galois fields in quantum mechanics
International Nuclear Information System (INIS)
Vourdas, A
2007-01-01
A 'Galois quantum system' in which the position and momentum take values in the Galois field GF(p l ) is considered. It is comprised of l-component systems which are coupled in a particular way and is described by a certain class of Hamiltonians. Displacements in the GF(p l ) x GF(p l ) phase space and the corresponding Heisenberg-Weyl group are studied. Symplectic transformations are shown to form the Sp(2, GF(p l )) group. Wigner and Weyl functions are defined and their properties are studied. Frobenius symmetries, which are based on Frobenius automorphisms in the theory of Galois fields, are a unique feature of these systems (for l ≥ 2). If they commute with the Hamiltonian, there are constants of motion which are discussed. An analytic representation in the l-sheeted complex plane provides an elegant formalism that embodies the properties of Frobenius transformations. The difference between a Galois quantum system and other finite quantum systems where the position and momentum take values in the ring [Z p l ] is discussed. (topical review)
N-body quantum scattering theory in two Hilbert spaces. VII. Real-energy limits
International Nuclear Information System (INIS)
Chandler, C.; Gibson, A.G.
1994-01-01
A study is made of the real-energy limits of approximate solutions of the Chandler--Gibson equations, as well as the real-energy limits of the approximate equations themselves. It is proved that (1) the approximate time-independent transition operator T π (z) and an auxiliary operator M π (z), when restricted to finite energy intervals, are trace class operators and have limits in trace norm for almost all values of the real energy; (2) the basic dynamical equation that determines the operator M π (z), when restricted to the space of trace class operators, has a real-energy limit in trace norm for almost all values of the real energy; (3) the real-energy limit of M π (z) is a solution of the real-energy limit equation; (4) the diagonal (on-shell) elements of the kernels of the real-energy limit of T π (z) and of all solutions of the real-energy limit equation exactly equal the on-shell transition operator, implying that the real-energy limit equation uniquely determines the physical transition amplitude; and (5) a sequence of approximate on-shell transition operators converges strongly to the exact on-shell transition operator. These mathematically rigorous results are believed to be the most general of their type for nonrelativistic N-body quantum scattering theories
Contagious architecture: computation, aesthetics, and space (technologies of lived abstraction)
Parisi, Luciana
2013-01-01
In Contagious Architecture, Luciana Parisi offers a philosophical inquiry into the status of the algorithm in architectural and interaction design. Her thesis is that algorithmic computation is not simply an abstract mathematical tool but constitutes a mode of thought in its own right, in that its operation extends into forms of abstraction that lie beyond direct human cognition and control. These include modes of infinity, contingency, and indeterminacy, as well as incomputable quantities underlying the iterative process of algorithmic processing. The main philosophical source for the project is Alfred North Whitehead, whose process philosophy is specifically designed to provide a vocabulary for "modes of thought" exhibiting various degrees of autonomy from human agency even as they are mobilized by it. Because algorithmic processing lies at the heart of the design practices now reshaping our world -- from the physical spaces of our built environment to the networked spaces of digital culture -- the nature o...
Man'ko, V. I.; Markovich, L. A.
2018-02-01
Quantum correlations in the state of four-level atom are investigated by using generic unitary transforms of the classical (diagonal) density matrix. Partial cases of pure state, X-state, Werner state are studied in details. The geometrical meaning of unitary Hilbert reference-frame rotations generating entanglement in the initially separable state is discussed. Characteristics of the entanglement in terms of concurrence, entropy and negativity are obtained as functions of the unitary matrix rotating the reference frame.
Abstracting Attribute Space for Transfer Function Exploration and Design.
Maciejewski, Ross; Jang, Yun; Woo, Insoo; Jänicke, Heike; Gaither, Kelly P; Ebert, David S
2013-01-01
Currently, user centered transfer function design begins with the user interacting with a one or two-dimensional histogram of the volumetric attribute space. The attribute space is visualized as a function of the number of voxels, allowing the user to explore the data in terms of the attribute size/magnitude. However, such visualizations provide the user with no information on the relationship between various attribute spaces (e.g., density, temperature, pressure, x, y, z) within the multivariate data. In this work, we propose a modification to the attribute space visualization in which the user is no longer presented with the magnitude of the attribute; instead, the user is presented with an information metric detailing the relationship between attributes of the multivariate volumetric data. In this way, the user can guide their exploration based on the relationship between the attribute magnitude and user selected attribute information as opposed to being constrained by only visualizing the magnitude of the attribute. We refer to this modification to the traditional histogram widget as an abstract attribute space representation. Our system utilizes common one and two-dimensional histogram widgets where the bins of the abstract attribute space now correspond to an attribute relationship in terms of the mean, standard deviation, entropy, or skewness. In this manner, we exploit the relationships and correlations present in the underlying data with respect to the dimension(s) under examination. These relationships are often times key to insight and allow us to guide attribute discovery as opposed to automatic extraction schemes which try to calculate and extract distinct attributes a priori. In this way, our system aids in the knowledge discovery of the interaction of properties within volumetric data.
Hilbert series for theories with Aharony duals
Energy Technology Data Exchange (ETDEWEB)
Hanany, Amihay [Theoretical Physics Group, Blackett Laboratory, Imperial College London,Prince Consort Road, London SW7 2AZ (United Kingdom); Hwang, Chiung; Kim, Hyungchul [Department of Physics, POSTECH, Pohang 790-784 (Korea, Republic of); Park, Jaemo [Department of Physics, POSTECH, Pohang 790-784 (Korea, Republic of); Postech Center for Theoretical Physics (PCTP), POSTECH,Pohang 790-784 (Korea, Republic of); Seong, Rak-Kyeong [School of Physics, Korea Institute for Advanced Study, 85 Hoegi-ro, Seoul 130-722 (Korea, Republic of)
2015-11-20
The algebraic structure of moduli spaces of 3d N=2 supersymmetric gauge theories is studied by computing the Hilbert series which is a generating function that counts gauge invariant operators in the chiral ring. These U(N{sub c}) theories with N{sub f} flavors have Aharony duals and their moduli spaces receive contributions from both mesonic and monopole operators. In order to compute the Hilbert series, recently developed techniques for Coulomb branch Hilbert series in 3d N=4 are extended to 3d N=2. The Hilbert series computation leads to a general expression of the algebraic variety which represents the moduli space of the U(N{sub c}) theory with N{sub f} flavors and its Aharony dual theory. A detailed analysis of the moduli space is given, including an analysis of the various components of the moduli space.
Indian Academy of Sciences (India)
This talk deals with the geometry of Banach spaces. A non-reflexive Banach space embeds canonically in its second dual and the process continues, giving raise to a strictly increasing chain of Banach spaces. A well known example of a geometric phenomenon that is preserved in this chain, is that of being (isometric) a ...
African Journals Online (AJOL)
University Health Services. Ahmadu Bella University, Zaria, Nigeria. ABSTRACT. Phywieo-chemical methods were used to analyse the commonly used lcualt samples bought from Zaria and Kano local markets. Blood-leadaoncentrations in ltuali ...
Power Spectral Density and Hilbert Transform
2016-12-01
2002. Pierce J. An introduction to information theory : symbols, signals , and noise. New York (NY): Dover Publications; 1980. Soumekh M. Fourier array...NOTES 14. ABSTRACT This technical report focuses on the Hilbert transform and some of its applications for digital signal processing. Herein we...review power spectral density and complex exponentials, and illustrate how the Hilbert transform converts a real signal (real in the sense of a real time
African Journals Online (AJOL)
Francis
Abstract. Aqueous, methanol and chloroform extracts from the leaves of Ficus religiosa, Thespesia populnea and Hibiscus tiliaceus were completely screened for antibacterial and antifungal activity. The chloroform extract of F. religiosa possessed a broad spectrum of antibacterial activity with a zone of inhibition of 10 to 21 ...
African Journals Online (AJOL)
Abstract·. A study was carried out to investigate the effect of overso~ing legumes on ~a~gela~d pe'rtormance in. Shinyanga'region, Tanzania. Four leguminous species namely Centrosema pubescence, Clito-':iii ternatea,. cMacroptilium atropurpureum and Stylosanthes hamata were Qversown in. a"natural ran,geland in a.
Indian Academy of Sciences (India)
65
Abstract. For well over three hundred years, the monsoon has been considered to be a gigantic land-sea breeze driven by the land-ocean contrast in surface temperature. In this paper, this hypothesis ..... primary driver of the monsoon in many papers and most textbooks (e.g. Lau and Li, 1984,. Webster 1987a, Meehl 1994, ...
African Journals Online (AJOL)
Email: jameskigera@yahoo.co.uk. ABSTRACT. Background: Implant orthopaedic surgery is associated with a risk of post operative Surgical Site. Infection (SSI). This can have devastating consequences in the case of arthroplasty. Due to the less than ideal circumstances under which surgery is conducted in Africa, there are ...
African Journals Online (AJOL)
WORKERS ON THEIR JOB PERFORMANCE IN IMO STATE, NIGERIA. NGOZI OKEREKE AND no. ONU. ABSTRACT. The study focused on the. eﬂ'ect of socioeconomic characteristics of ﬁeld extension workers on their job performance in.1mo state agricultural development programme, Nigeria. Data was collected with the ...
African Journals Online (AJOL)
PROF. OLIVER OSUAGWA
Abstract. Many mathematical models of stochastic dynamical systems were based on the assumption that the drift and volatility coefficients were linear function of the solution. In this work, we arrive at the drift and the volatility by observing the dynamics of change in the selected stocks in a sufficiently small interval t∆ .
Compact Hilbert Curve Index Algorithm Based on Gray Code
Directory of Open Access Journals (Sweden)
CAO Xuefeng
2016-12-01
Full Text Available Hilbert curve has best clustering in various kinds of space filling curves, and has been used as an important tools in discrete global grid spatial index design field. But there are lots of redundancies in the standard Hilbert curve index when the data set has large differences between dimensions. In this paper, the construction features of Hilbert curve is analyzed based on Gray code, and then the compact Hilbert curve index algorithm is put forward, in which the redundancy problem has been avoided while Hilbert curve clustering preserved. Finally, experiment results shows that the compact Hilbert curve index outperforms the standard Hilbert index, their 1 computational complexity is nearly equivalent, but the real data set test shows the coding time and storage space decrease 40%, the speedup ratio of sorting speed is nearly 4.3.
Directory of Open Access Journals (Sweden)
Mustafa Inc
2013-01-01
Full Text Available The present paper emphasizes Jeffery-Hamel flow: fluid flow between two rigid plane walls, where the angle between them is 2α. A new method called the reproducing kernel Hilbert space method (RKHSM is briefly introduced. The validity of the reproducing kernel method is set by comparing our results with HAM, DTM, and HPM and numerical results for different values of H, α, and Re. The results show up that the proposed reproducing kernel method can achieve good results in predicting the solutions of such problems. Comparison between obtained results showed that RKHSM is more acceptable and accurate than other methods. This method is very useful and applicable for solving nonlinear problems.
2013-01-01
David Hilbert was one of the great mathematicians who expounded the centrality of their subject in human thought. In this collection of essays, Wilfried Sieg frames Hilbert's foundational work, from 1890 to 1939, in a comprehensive way and integrates it with modern proof theoretic investigations. Ten essays are devoted to the analysis of classical as well as modern proof theory; three papers on the mathematical roots of Hilbert's work precede the analytical core, and three final essays exploit an open philosophical horizon for reflection on the nature of mathematics in the 21st century.
Charting the invisible in phase space (Abstract only)
Indian Academy of Sciences (India)
2012-06-09
derejula@cern.ch. Abstract. One challenge in particle physics is that not all the momenta relevant to many processes are observable. Some particles are nearly invisible (neutrinos and hypothetical neutralinos), others.
Standard State Space Models of Unawareness (Extended Abstract
Directory of Open Access Journals (Sweden)
Peter Fritz
2016-06-01
Full Text Available The impossibility theorem of Dekel, Lipman and Rustichini has been thought to demonstrate that standard state-space models cannot be used to represent unawareness. We first show that Dekel, Lipman and Rustichini do not establish this claim. We then distinguish three notions of awareness, and argue that although one of them may not be adequately modeled using standard state spaces, there is no reason to think that standard state spaces cannot provide models of the other two notions. In fact, standard space models of these forms of awareness are attractively simple. They allow us to prove completeness and decidability results with ease, to carry over standard techniques from decision theory, and to add propositional quantifiers straightforwardly.
(abstract) The Nest Generation of Space Flight Computers
Alkalaj, Leon; Panwar, Ramesh
1993-01-01
To meet new design objectives for drastic reductions in mass, size, and power consumption, the Flight Computer Development Group at JPL is participating in a design study and development of a light-weight, small-sized, low-power 3-D Space Flight Computer. In this paper, we will present a detailed design and tradeoff study of the proposed computer. We will also discuss a complete design of the multichip modules and their size, weight, and power consumption. Prelimimary thermal models will also be discussed.
(abstract) Deep Space Network Radiometric Remote Sensing Program
Walter, Steven J.
1994-01-01
Planetary spacecraft are viewed through a troposphere that absorbs and delays radio signals propagating through it. Tropospheric water, in the form of vapor, cloud liquid,and precipitation , emits radio noise which limits satellite telemetry communication link performance. Even at X-band, rain storms have severely affected several satellite experiments including a planetary encounter. The problem will worsen with DSN implementation of Ka-band becausecommunication link budgets will be dominated by tropospheric conditions. Troposphere-induced propagation delays currently limit VLBI accuracy and are significant sources of error for Doppler tracking. Additionally, the success of radio science programs such as satellite gravity wave experiments and atmospheric occultation experiments depends on minimizing the effect of watervapor-induced prop agation delays. In order to overcome limitations imposed by the troposphere, the Deep Space Network has supported a program of radiometric remote sensing. Currently, water vapor radiometers (WVRs) and microwave temperature profilers (MTPs) support many aspects of the Deep Space Network operations and research and development programs. Their capability to sense atmospheric water, microwave sky brightness, and atmospheric temperature is critical to development of Ka-band telemetry systems, communication link models, VLBI, satellite gravity waveexperiments, and r adio science missions. During 1993, WVRs provided data for propagation mode development, supp orted planetary missions, and demonstrated advanced tracking capability. Collection of atmospheric statistics is necessary to model and predict performance of Ka-band telemetry links, antenna arrays, and radio science experiments. Since the spectrum of weather variations has power at very long time scales, atmospheric measurements have been requested for periods ranging from one year to a decade at each DSN site. The resulting database would provide reliable statistics on daily
Hilbert space and quantum mechanics
Gallone, Franco
2015-01-01
The topics of this book are the mathematical foundations of non-relativistic quantum mechanics and the mathematical theory they require. The main characteristic of the book is that the mathematics is developed assuming familiarity with elementary analysis only. Moreover, all the proofs are carried out in detail. These features make the book easily accessible to readers with only the mathematical training offered by undergraduate education in mathematics or in physics, and also ideal for individual study. The principles of quantum mechanics are discussed with complete mathematical accuracy and an effort is made to always trace them back to the experimental reality that lies at their root. The treatment of quantum mechanics is axiomatic, with definitions followed by propositions proved in a mathematical fashion. No previous knowledge of quantum mechanics is required. This book is designed so that parts of it can be easily used for various courses in mathematics and mathematical physics, as suggested in the Pref...
Quantum mechanics in Hilbert space
Prugovecki, Eduard
1981-01-01
A critical presentation of the basic mathematics of nonrelativistic quantum mechanics, this text is suitable for courses in functional analysis at the advanced undergraduate and graduate levels. Its readable and self-contained form is accessible even to students without an extensive mathematical background. Applications of basic theorems to quantum mechanics make it of particular interest to mathematicians working in functional analysis and related areas.This text features the rigorous proofs of all the main functional-analytic statements encountered in books on quantum mechanics. It fills the
Directory of Open Access Journals (Sweden)
Chang Tong-Huei
2009-01-01
Full Text Available We use a concept of abstract convexity to define the almost - property, al- - family, and almost -spaces. We get some new approximate fixed point theorems and fixed point theorems in almost -spaces. Our results extend some results of other authors.
Chen, Judy F.; Warden, Clyde A.; Tai, David Wen-Shung; Chen, Farn-Shing; Chao, Chich-Yang
2011-01-01
Virtual spaces allow abstract representations of reality that not only encourage student self-directed learning but also reinforce core content of the learning objective through visual metaphors not reproducible in the physical world. One of the advantages of such a space is the ability to escape the restrictions of the physical classroom, yet…
Cervone, Jason A.
2017-01-01
This paper examines the situating of rural communities in the United States within the neoliberal global context. It will focus on Henri Lefebvre's concept of abstract space, as well as additional theories on the ways space is produced and understood. The paper will use these theories to create an understanding of the ways rural communities are…
Exploring Interaction Space as Abstraction Mechanism for Task-Based User Interface Design
DEFF Research Database (Denmark)
Nielsen, C. M.; Overgaard, M.; Pedersen, M. B.
2007-01-01
, but there is considerable variation in the other models that are employed. This paper explores the extent to which the notion of interaction space is useful as an abstraction mechanism to reduce the complexity of creating and specifying a user interface design. We present how we designed a specific user interface through...... use of design techniques and models that employ the notion of interaction space. This design effort departed from the task models in an object-oriented model of the users’ problem and application domains. The lessons learned emphasize that the notion of interactions spaces is a useful abstraction...
HILBERT BETWEEN THE FORMAL AND THE INFORMAL SIDE OF MATHEMATICS
Directory of Open Access Journals (Sweden)
GIORGIO VENTURI
Full Text Available Abstract: In this article we analyze the key concept of Hilbert's axiomatic method, namely that of axiom. We will find two different concepts: the first one from the period of Hilbert's foundation of geometry and the second one at the time of the development of his proof theory. Both conceptions are linked to two different notions of intuition and show how Hilbert's ideas are far from a purely formalist conception of mathematics. The principal thesis of this article is that one of the main problems that Hilbert encountered in his foundational studies consisted in securing a link between formalization and intuition. We will also analyze a related problem, that we will call "Frege's Problem", form the time of the foundation of geometry and investigate the role of the Axiom of Completeness in its solution.
Abstract graph-like space and vector-valued metric graphs
Post, Olaf
2016-01-01
In this note we present some abstract ideas how one can construct spaces from building blocks according to a graph. The coupling is expressed via boundary pairs, and can be applied to very different spaces such as discrete graphs, quantum graphs or graph-like manifolds. We show a spectral analysis of graph-like spaces, and consider as a special case vector-valued quantum graphs. Moreover, we provide a prototype of a convergence theorem for shrinking graph-like spaces with Dirichlet boundary c...
13 th International Workshop on Greenhouse Gas Measurements from Space - Book of Abstracts
Verronen, Pekka
2017-01-01
The 13th International Workshop on Greenhouse Gas Measurements from Space (IWGGMS) will be held on 6-8 June, 2017, at the University of Helsinki in Helsinki, Finland. The workshop is organised by the Finnish Meteorological Institute with support from the University of Helsinki. The workshop gathers together more than 160 scientists from the EU, USA, Japan, China, Australia, Canada, and Russia. This report is the official abstract book of the workshop. Background. Success in space-based glo...
Guided search for hybrid systems based on coarse-grained space abstractions.
Bogomolov, Sergiy; Donzé, Alexandre; Frehse, Goran; Grosu, Radu; Johnson, Taylor T; Ladan, Hamed; Podelski, Andreas; Wehrle, Martin
Hybrid systems represent an important and powerful formalism for modeling real-world applications such as embedded systems. A verification tool like SpaceEx is based on the exploration of a symbolic search space (the region space ). As a verification tool, it is typically optimized towards proving the absence of errors. In some settings, e.g., when the verification tool is employed in a feedback-directed design cycle, one would like to have the option to call a version that is optimized towards finding an error trajectory in the region space. A recent approach in this direction is based on guided search . Guided search relies on a cost function that indicates which states are promising to be explored, and preferably explores more promising states first. In this paper, we propose an abstraction-based cost function based on coarse-grained space abstractions for guiding the reachability analysis. For this purpose, a suitable abstraction technique that exploits the flexible granularity of modern reachability analysis algorithms is introduced. The new cost function is an effective extension of pattern database approaches that have been successfully applied in other areas. The approach has been implemented in the SpaceEx model checker. The evaluation shows its practical potential.
Abstract interpolation in vector-valued de Branges-Rovnyak spaces
Ball, J.A.; Bolotnikov, V.; ter Horst, S.
2011-01-01
Following ideas from the Abstract Interpolation Problem of Katsnelson et al. (Operators in spaces of functions and problems in function theory, vol 146, pp 83–96, Naukova Dumka, Kiev, 1987) for Schur class functions, we study a general metric constrained interpolation problem for functions from a
Signal Analysis by Generalized Hilbert Transforms on the Unit Sphere
International Nuclear Information System (INIS)
Wietzke, Lennart; Fleischmann, Oliver; Sommer, Gerald
2008-01-01
In 1D signal processing local energy and phase can be determined by the analytic signal. Local energy, phase and orientation of 2D signals can be analyzed by the monogenic signal for all i(ntrinsic)1D signals in an rotational invariant way by the generalized Hilbert transform. In order to analyze both i1D and i2D signals in one framework the main idea of this contribution is to lift up 2D signals to the higher dimensional conformal space in which the original signal can be analyzed with more degrees of freedom by the generalized Hilbert transform on the unit sphere. An appropriate embedding of 2D signals on the unit sphere results in an extended feature space spanned by local energy, phase, orientation/direction and curvature. In contrast to classical differential geometry, local curvature can now be determined by the generalized Hilbert transform in monogenic scale space without any derivatives.
Precise asymptotics for complete moment convergence in Hilbert ...
Indian Academy of Sciences (India)
gence in Banach spaces. Further, the exact convergence rates of the complete moment convergence have also been studied, and one can refer to Jiang and Zhang [11] and Li. [12] for details. Recently, Huang and Zhang [8] obtained the precise rates in the law of the loga- rithm for Hilbert-space valued random variables.
Frames and other bases in abstract and function spaces novel methods in harmonic analysis
Gia, Quoc; Mayeli, Azita; Mhaskar, Hrushikesh; Zhou, Ding-Xuan
2017-01-01
The first of a two volume set on novel methods in harmonic analysis, this book draws on a number of original research and survey papers from well-known specialists detailing the latest innovations and recently discovered links between various fields. Along with many deep theoretical results, these volumes contain numerous applications to problems in signal processing, medical imaging, geodesy, statistics, and data science. The chapters within cover an impressive range of ideas from both traditional and modern harmonic analysis, such as: the Fourier transform, Shannon sampling, frames, wavelets, functions on Euclidean spaces, analysis on function spaces of Riemannian and sub-Riemannian manifolds, Fourier analysis on manifolds and Lie groups, analysis on combinatorial graphs, sheaves, co-sheaves, and persistent homologies on topological spaces. Volume I is organized around the theme of frames and other bases in abstract and function spaces, covering topics such as: The advanced development of frames, including ...
Hilbert W*-modules and coherent states
International Nuclear Information System (INIS)
Bhattacharyya, T; Roy, S Shyam
2012-01-01
Hilbert C*-module valued coherent states was introduced earlier by Ali, Bhattacharyya and Shyam Roy. We consider the case when the underlying C*-algebra is a W*-algebra. The construction is similar with a substantial gain. The associated reproducing kernel is now algebra valued, rather than taking values in the space of bounded linear operators between two C*-algebras. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’. (paper)
Nice surjections on spaces of operators
Indian Academy of Sciences (India)
Abstract. A bounded linear operator is said to be nice if its adjoint preserves extreme points of the dual unit ball. Motivated by a description due to Labuschagne and Mas- cioni [9] of such maps for the space of compact operators on a Hilbert space, in this article we consider a description of nice surjections on K(X, Y ) for ...
Possibilities of identifying cyber attack in noisy space of n-dimensional abstract system
Jašek, Roman; Dvořák, Jiří; Janková, Martina; Sedláček, Michal
2016-06-01
This article briefly mentions some selected options of current concept for identifying cyber attacks from the perspective of the new cyberspace of real system. In the cyberspace, there is defined n-dimensional abstract system containing elements of the spatial arrangement of partial system elements such as micro-environment of cyber systems surrounded by other suitably arranged corresponding noise space. This space is also gradually supplemented by a new image of dynamic processes in a discreet environment, and corresponding again to n-dimensional expression of time space defining existence and also the prediction for expected cyber attacksin the noise space. Noises are seen here as useful and necessary for modern information and communication technologies (e.g. in processes of applied cryptography in ICT) and then the so-called useless noises designed for initial (necessary) filtering of this highly aggressive environment and in future expectedly offensive background in cyber war (e.g. the destruction of unmanned means of an electromagnetic pulse, or for destruction of new safety barriers created on principles of electrostatic field or on other principles of modern physics, etc.). The key to these new options is the expression of abstract systems based on the models of microelements of cyber systems and their hierarchical concept in structure of n-dimensional system in given cyberspace. The aim of this article is to highlight the possible systemic expression of cyberspace of abstract system and possible identification in time-spatial expression of real environment (on microelements of cyber systems and their surroundings with noise characteristics and time dimension in dynamic of microelements' own time and externaltime defined by real environment). The article was based on a partial task of faculty specific research.
Possibilities of identifying cyber attack in noisy space of n-dimensional abstract system
Energy Technology Data Exchange (ETDEWEB)
Jašek, Roman; Dvořák, Jiří; Janková, Martina; Sedláček, Michal [Tomas Bata University in Zlin Nad Stranemi 4511, 760 05 Zlin, Czech republic jasek@fai.utb.cz, dvorakj@aconte.cz, martina.jankova@email.cz, michal.sedlacek@email.cz (Czech Republic)
2016-06-08
This article briefly mentions some selected options of current concept for identifying cyber attacks from the perspective of the new cyberspace of real system. In the cyberspace, there is defined n-dimensional abstract system containing elements of the spatial arrangement of partial system elements such as micro-environment of cyber systems surrounded by other suitably arranged corresponding noise space. This space is also gradually supplemented by a new image of dynamic processes in a discreet environment, and corresponding again to n-dimensional expression of time space defining existence and also the prediction for expected cyber attacksin the noise space. Noises are seen here as useful and necessary for modern information and communication technologies (e.g. in processes of applied cryptography in ICT) and then the so-called useless noises designed for initial (necessary) filtering of this highly aggressive environment and in future expectedly offensive background in cyber war (e.g. the destruction of unmanned means of an electromagnetic pulse, or for destruction of new safety barriers created on principles of electrostatic field or on other principles of modern physics, etc.). The key to these new options is the expression of abstract systems based on the models of microelements of cyber systems and their hierarchical concept in structure of n-dimensional system in given cyberspace. The aim of this article is to highlight the possible systemic expression of cyberspace of abstract system and possible identification in time-spatial expression of real environment (on microelements of cyber systems and their surroundings with noise characteristics and time dimension in dynamic of microelements’ own time and externaltime defined by real environment). The article was based on a partial task of faculty specific research.
Topological freeness for Hilbert bimodules
DEFF Research Database (Denmark)
Kwasniewski, Bartosz
2014-01-01
It is shown that topological freeness of Rieffel’s induced representation functor implies that any C*-algebra generated by a faithful covariant representation of a Hilbert bimodule X over a C*-algebra A is canonically isomorphic to the crossed product A ⋊ X ℤ. An ideal lattice description and a s...
Equivalence of quotient Hilbert modules
Indian Academy of Sciences (India)
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
Texas A&M University, College Station, Texas 77843, USA. ∗. Indian Statistical Institute, R.V. College ... least, locally) as the zero set of a single analytic function ϕ. Let A( ) be the algebra of functions ...... [6] Douglas R G and Misra G, Geometric invariants for resolutions of Hilbert modules, in. Operator Theory: Advances and ...
Four-dimensional hilbert curves for R-trees
DEFF Research Database (Denmark)
Haverkort, Herman; Walderveen, Freek van
2011-01-01
Two-dimensional R-trees are a class of spatial index structures in which objects are arranged to enable fast window queries: report all objects that intersect a given query window. One of the most successful methods of arranging the objects in the index structure is based on sorting the objects...... according to the positions of their centers along a two-dimensional Hilbert space-filling curve. Alternatively, one may use the coordinates of the objects' bounding boxes to represent each object by a four-dimensional point, and sort these points along a four-dimensional Hilbert-type curve. In experiments...
Lectures on Hilbert modular varieties and modular forms
Goren, Eyal Z
2001-01-01
This book is devoted to certain aspects of the theory of p-adic Hilbert modular forms and moduli spaces of abelian varieties with real multiplication. The theory of p-adic modular forms is presented first in the elliptic case, introducing the reader to key ideas of N. M. Katz and J.-P. Serre. It is re-interpreted from a geometric point of view, which is developed to present the rudiments of a similar theory for Hilbert modular forms. The theory of moduli spaces of abelian varieties with real multiplication is presented first very explicitly over the complex numbers. Aspects of the general theory are then exposed, in particular, local deformation theory of abelian varieties in positive characteristic. The arithmetic of p-adic Hilbert modular forms and the geometry of moduli spaces of abelian varieties are related. This relation is used to study q-expansions of Hilbert modular forms, on the one hand, and stratifications of moduli spaces on the other hand. The book is addressed to graduate students and non-exper...
Speaker Profiles and Abstracts
Indian Academy of Sciences (India)
2016-11-05
Nov 5, 2016 ... a polarised fashion. Their work thus illuminates how Cas1-2 complex and IHF coordinate bring about the preferential integration of protospacer into the leader proximal end. Speaker's Profile. B Anand, IIT ... has a realization formula where a Hilbert space makes a natural appearance. Agler in 1990 found a ...
Hörmander spaces, interpolation, and elliptic problems
Mikhailets, Vladimir A; Malyshev, Peter V
2014-01-01
The monograph gives a detailed exposition of the theory of general elliptic operators (scalar and matrix) and elliptic boundary value problems in Hilbert scales of Hörmander function spaces. This theory was constructed by the authors in a number of papers published in 2005-2009. It is distinguished by a systematic use of the method of interpolation with a functional parameter of abstract Hilbert spaces and Sobolev inner product spaces. This method, the theory and their applications are expounded for the first time in the monographic literature. The monograph is written in detail and in a
Clustering in Hilbert simplex geometry
Nielsen, Frank
2017-04-03
Clustering categorical distributions in the probability simplex is a fundamental primitive often met in applications dealing with histograms or mixtures of multinomials. Traditionally, the differential-geometric structure of the probability simplex has been used either by (i) setting the Riemannian metric tensor to the Fisher information matrix of the categorical distributions, or (ii) defining the information-geometric structure induced by a smooth dissimilarity measure, called a divergence. In this paper, we introduce a novel computationally-friendly non-Riemannian framework for modeling the probability simplex: Hilbert simplex geometry. We discuss the pros and cons of those three statistical modelings, and compare them experimentally for clustering tasks.
An image encryption algorithm utilizing julia sets and hilbert curves.
Directory of Open Access Journals (Sweden)
Yuanyuan Sun
Full Text Available Image encryption is an important and effective technique to protect image security. In this paper, a novel image encryption algorithm combining Julia sets and Hilbert curves is proposed. The algorithm utilizes Julia sets' parameters to generate a random sequence as the initial keys and gets the final encryption keys by scrambling the initial keys through the Hilbert curve. The final cipher image is obtained by modulo arithmetic and diffuse operation. In this method, it needs only a few parameters for the key generation, which greatly reduces the storage space. Moreover, because of the Julia sets' properties, such as infiniteness and chaotic characteristics, the keys have high sensitivity even to a tiny perturbation. The experimental results indicate that the algorithm has large key space, good statistical property, high sensitivity for the keys, and effective resistance to the chosen-plaintext attack.
An image encryption algorithm utilizing julia sets and hilbert curves.
Sun, Yuanyuan; Chen, Lina; Xu, Rudan; Kong, Ruiqing
2014-01-01
Image encryption is an important and effective technique to protect image security. In this paper, a novel image encryption algorithm combining Julia sets and Hilbert curves is proposed. The algorithm utilizes Julia sets' parameters to generate a random sequence as the initial keys and gets the final encryption keys by scrambling the initial keys through the Hilbert curve. The final cipher image is obtained by modulo arithmetic and diffuse operation. In this method, it needs only a few parameters for the key generation, which greatly reduces the storage space. Moreover, because of the Julia sets' properties, such as infiniteness and chaotic characteristics, the keys have high sensitivity even to a tiny perturbation. The experimental results indicate that the algorithm has large key space, good statistical property, high sensitivity for the keys, and effective resistance to the chosen-plaintext attack.
Quantum Hilbert matrices and orthogonal polynomials
DEFF Research Database (Denmark)
Andersen, Jørgen Ellegaard; Berg, Christian
2009-01-01
Using the notion of quantum integers associated with a complex number q≠0 , we define the quantum Hilbert matrix and various extensions. They are Hankel matrices corresponding to certain little q -Jacobi polynomials when |q|... of reciprocal Fibonacci numbers called Filbert matrices. We find a formula for the entries of the inverse quantum Hilbert matrix....
6th Hilbert's problem and S.Lie's infinite groups
International Nuclear Information System (INIS)
Konopleva, N.P.
1999-01-01
The progress in Hilbert's sixth problem solving is demonstrated. That became possible thanks to the gauge field theory in physics and to the geometrical treatment of the gauge fields. It is shown that the fibre bundle spaces geometry is the best basis for solution of the problem being discussed. This talk has been reported at the International Seminar '100 Years after Sophus Lie' (Leipzig, Germany)
Criswell, D. R. (Editor)
1976-01-01
The practicality of exploiting the moon, not only as a source of materials for large habitable structures at Lagrangian points, but also as a base for colonization is discussed in abstracts of papers presented at a special session on lunar utilization. Questions and answers which followed each presentation are included after the appropriate abstract. Author and subject indexes are provided.
Hilbert space theory of classical electrodynamics
Indian Academy of Sciences (India)
Furthermore, following Bondar et al, {\\it Phys. Rev.} A 88, 052108 (2013), it is pointed out that quantum processes that preserve the positivity or nonpositivity of theWigner function can be implemented by classical optics. This may be useful in interpreting quantum information processing in terms of classical optics.
Rigged Hilbert space, duality, and cosmology
International Nuclear Information System (INIS)
Castagnino, Mario A.
1997-01-01
The evolution of the universe and that of most of its subsystems are time asymmetric which contrasts the time symmetric laws of physics. The aim of this paper is to prove that, from causality and the global nature of time asymmetry this asymmetry can be derived at the fundamental quantum level, defining a growing entropy and the outcome of equilibrium, explaining the decaying processes, etc
Quantum mechanics: why complex Hilbert space?
Cassinelli, G; Lahti, P
2017-11-13
We outline a programme for an axiomatic reconstruction of quantum mechanics based on the statistical duality of states and effects that combines the use of a theorem of Solér with the idea of symmetry. We also discuss arguments favouring the choice of the complex field.This article is part of the themed issue 'Second quantum revolution: foundational questions'. © 2017 The Author(s).
Hilbert space methods for partial differential equations
Directory of Open Access Journals (Sweden)
Ralph E. Showalter
1994-09-01
Full Text Available This book is an outgrowth of a course which we have given almost periodically over the last eight years. It is addressed to beginning graduate students of mathematics, engineering, and the physical sciences. Thus, we have attempted to present it while presupposing a minimal background: the reader is assumed to have some prior acquaintance with the concepts of ``linear'' and ``continuous'' and also to believe $L^2$ is complete. An undergraduate mathematics training through Lebesgue integration is an ideal background but we dare not assume it without turning away many of our best students. The formal prerequisite consists of a good advanced calculus course and a motivation to study partial differential equations.
USSR and Eastern Europe Scienitific Abstracts, Geophysics, Astronomy and Space. Number 399
1977-06-10
cosmonauts underwent functional in- vestigations at a state of rest and while performing a measured physical load. Cardiovascular activity is investigated...No 3, 1977 3.62.481K [Abstract of article by L. S. Gurin and K. A. Tsoy; Moscow, MNOGOUROVNEVAYA SISTEMA ALGORITMOV OBNARUZHENIYA I VYDELENIYA...3.62.321 [Abstract of article by A. K. Platonov and R. K. Kazakova; Moscow, SISTEMA PROYEKTIROVANIYA ORBIT V PRIKLADNYKH ZADACHAKH NEBESNOY MEKHANIKI
USSR and Eastern Europe Scientific Abstracts, Geophysics, Astronomy and Space, Number 394.
1977-04-13
Particularly interesting was the multiday work in the complex structur- al maze of deep narrow troughs and a submarine ridge in the neighborhood of...SVODNYY TOM in Russian No 1, 1977 1G258 [Abstract of article by Yu. A. Tarakanov, M. B. Stepanova and N. S. Medved- eva ; Moscow, METODY OBRAB. I
Generalized n-circular projections on JB*-triples and Hilbert C0(Ω-modules
Directory of Open Access Journals (Sweden)
Ilišević Dijana
2017-10-01
Full Text Available Being expected as a Banach space substitute of the orthogonal projections on Hilbert spaces, generalized n-circular projections also extend the notion of generalized bicontractive projections on JB*-triples. In this paper, we study some geometric properties of JB*-triples related to them. In particular, we provide some structure theorems of generalized n-circular projections on an often mentioned special case of JB*-triples, i.e., Hilbert C*-modules over abelian C*-algebras C0(Ω.
On equivariant embedding of Hilbert C C C modules
Indian Academy of Sciences (India)
with A replaced by A ⊗ H for an arbitrary Hilbert space H. The main idea is to exploit the 'smooth' topology on A∞ ⊗alg H∞. (which is a common subspace of both (A ⊗ H)∞ and ( ˜A ⊗ H)∞. ), given by the A∞. -valued inner product. A sequence ξn is Cauchy in this topology if and only if 〈(ξn − ξm), (ξn − ξm)〉 goes to 0 in the ...
On the Hilbert-Huang Transform Theoretical Developments
Kizhner, Semion; Blank, Karin; Flatley, Thomas; Huang, Norden E.; Patrick, David; Hestnes, Phyllis
2005-01-01
One of the main heritage tools used in scientific and engineering data spectrum analysis is the Fourier Integral Transform and its high performance digital equivalent - the Fast Fourier Transform (FFT). Both carry strong a-priori assumptions about the source data, such as linearity, of being stationary, and of satisfying the Dirichlet conditions. A recent development at the National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC), known as the Hilbert-Huang Transform (HHT), proposes a novel approach to the solution for the nonlinear class of spectrum analysis problems. Using a-posteriori data processing based on the Empirical Mode Decomposition (EMD) sifting process (algorithm), followed by the normalized Hilbert Transform of the decomposition data, the HHT allows spectrum analysis of nonlinear and nonstationary data. The EMD sifting process results in a non-constrained decomposition of a source real value data vector into a finite set of Intrinsic Mode Functions (IMF). These functions form a near orthogonal adaptive basis, a basis that is derived from the data. The IMFs can be further analyzed for spectrum interpretation by the classical Hilbert Transform. A new engineering spectrum analysis tool using HHT has been developed at NASA GSFC, the HHT Data Processing System (HHT-DPS). As the HHT-DPS has been successfully used and commercialized, new applications post additional questions about the theoretical basis behind the HHT and EMD algorithms. Why is the fastest changing component of a composite signal being sifted out first in the EMD sifting process? Why does the EMD sifting process seemingly converge and why does it converge rapidly? Does an IMF have a distinctive structure? Why are the IMFs near orthogonal? We address these questions and develop the initial theoretical background for the HHT. This will contribute to the developments of new HHT processing options, such as real-time and 2-D processing using Field Programmable
Commentaries on Hilbert's Basis Theorem | Apine | Science World ...
African Journals Online (AJOL)
The famous basis theorem of David Hilbert is an important theorem in commutative algebra. In particular the Hilbert's basis theorem is the most important source of Noetherian rings which are by far the most important class of rings in commutative algebra. In this paper we have used Hilbert's theorem to examine their unique ...
Theory and experiments on Peano and Hilbert curve RFID tags
McVay, John; Hoorfar, Ahmad; Engheta, Nader
2006-05-01
Recently, there has been considerable interest in the area of Radio Frequency Identification (RFID) and Radio Frequency Tagging (RFTAG). This emerging area of interest can be applied for inventory control (commercial) as well as friend/foe identification (military) to name but a few. The current technology can be broken down into two main groups, namely passive and active RFID tags. Utilization of Space-Filling Curve (SFC) geometries, such as the Peano and Hilbert curves, has been recently investigated for use in completely passive RFID applications [1, 2]. In this work, we give an overview of our work on the space-filling curves and the potential for utilizing the electrically small, resonant characteristics of these curves for use in RFID technologies with an emphasis on the challenging issues involved when attempting to tag conductive objects. In particular, we investigate the possible use of these tags in conjunction with high impedance ground-planes made of Hilbert or Peano curve inclusions [3, 4] to develop electrically small RFID tags that may also radiate efficiently, within close proximity of large conductive objects [5].
Hilbert's Grand Hotel with a series twist
Wijeratne, Chanakya; Mamolo, Ami; Zazkis, Rina
2014-08-01
This paper presents a new twist on a familiar paradox, linking seemingly disparate ideas under one roof. Hilbert's Grand Hotel, a paradox which addresses infinite set comparisons is adapted and extended to incorporate ideas from calculus - namely infinite series. We present and resolve several variations, and invite the reader to explore his or her own variations.
Notes on Hilbert and Cauchy Matrices
Czech Academy of Sciences Publication Activity Database
Fiedler, Miroslav
2010-01-01
Roč. 432, č. 1 (2010), s. 351-356 ISSN 0024-3795 Institutional research plan: CEZ:AV0Z10300504 Keywords : Hilbert matrix * Cauchy matrix * combined matrix * AT-property Subject RIV: BA - General Mathematics Impact factor: 1.005, year: 2010
Noise properties of Hilbert transform evaluation
Czech Academy of Sciences Publication Activity Database
Pavlíček, Pavel; Svak, V.
2015-01-01
Roč. 26, č. 8 (2015), s. 085207 ISSN 0957-0233 R&D Projects: GA ČR GA13-12301S Institutional support: RVO:68378271 Keywords : Hilbert transform * noise * measurement uncertainty * white-light interferometry * fringe -pattern analysis Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.492, year: 2015
A relative Hilbert-Mumford criterion
DEFF Research Database (Denmark)
Gulbrandsen, Martin G.; Halle, Lars Halvard; Hulek, Klaus
2015-01-01
We generalize the classical Hilbert-Mumford criteria for GIT (semi-)stability in terms of one parameter subgroups of a linearly reductive group G over a field k, to the relative situation of an equivariant, projective morphism X -> Spec A to a noetherian k-algebra A. We also extend the classical...
Experimental Investigation of a Direct Methanol Fuel Cell with Hilbert Fractal Current Collectors
Directory of Open Access Journals (Sweden)
Jing-Yi Chang
2014-01-01
Full Text Available The Hilbert curve is a continuous type of fractal space-filling curve. This fractal curve visits every point in a square grid with a size of 2×2, 4×4, or any other power of two. This paper presents Hilbert fractal curve application to direct methanol fuel cell (DMFC current collectors. The current collectors are carved following first, second, and third order Hilbert fractal curves. These curves give the current collectors different free open ratios and opening perimeters. We conducted an experimental investigation into DMFC performance as a function of the free open ratio and opening perimeter on the bipolar plates. Nyquist plots of the bipolar plates are made and compared using electrochemical impedance spectroscopy (EIS experiments to understand the phenomena in depth. The results obtained in this paper could be a good reference for future current collector design.
nth roots with Hilbert-Schmidt defect operator of normal contractions
International Nuclear Information System (INIS)
Duggal, B.P.
1992-08-01
Let T be a normal contraction (on a complex separable Hilbert space H into itself) with an nth root A such that the defect operator D A =(1-A*A) 1/2 is of the Hilbert-Schmidt class C 2 . Then either A is normal or A is similar to a normal contraction. In the case in which T is hyponormal, A n =T and D A is an element of C 2 , A is a ''coupling'' of a contraction similar to a normal contraction and a contraction which is the quasi-affine transform of a unilateral shift. These results are applied to prove a (Putnam-Fuglede type) commutatively theorem for operator valued roots of commutative analytic functions and hyponormal contractions T which have an nth root with Hilbert-Schmidt defect operator. 23 refs
Tool Wear Feature Extraction Based on Hilbert Marginal Spectrum
Guan, Shan; Song, Weijie; Pang, Hongyang
2017-09-01
In the metal cutting process, the signal contains a wealth of tool wear state information. A tool wear signal’s analysis and feature extraction method based on Hilbert marginal spectrum is proposed. Firstly, the tool wear signal was decomposed by empirical mode decomposition algorithm and the intrinsic mode functions including the main information were screened out by the correlation coefficient and the variance contribution rate. Secondly, Hilbert transform was performed on the main intrinsic mode functions. Hilbert time-frequency spectrum and Hilbert marginal spectrum were obtained by Hilbert transform. Finally, Amplitude domain indexes were extracted on the basis of the Hilbert marginal spectrum and they structured recognition feature vector of tool wear state. The research results show that the extracted features can effectively characterize the different wear state of the tool, which provides a basis for monitoring tool wear condition.
Xu, Wenjun; Tang, Chen; Su, Yonggang; Li, Biyuan; Lei, Zhenkun
2018-02-01
In this paper, we propose an image decomposition model Shearlet-Hilbert-L 2 with better performance for denoising in electronic speckle pattern interferometry (ESPI) fringe patterns. In our model, the low-density fringes, high-density fringes, and noise are, respectively, described by shearlet smoothness spaces, adaptive Hilbert space, and L 2 space and processed individually. Because the shearlet transform has superior directional sensitivity, our proposed Shearlet-Hilbert-L 2 model achieves commendable filtering results for various types of ESPI fringe patterns, including uniform density fringe patterns, moderately variable density fringe patterns, and greatly variable density fringe patterns. We evaluate the performance of our proposed Shearlet-Hilbert-L 2 model via application to two computer-simulated and nine experimentally obtained ESPI fringe patterns with various densities and poor quality. Furthermore, we compare our proposed model with windowed Fourier filtering and coherence-enhancing diffusion, both of which are the state-of-the-art methods for ESPI fringe patterns denoising in transform domain and spatial domain, respectively. We also compare our proposed model with the previous image decomposition model BL-Hilbert-L 2 .
Nested Hilbert schemes on surfaces: Virtual fundamental class
DEFF Research Database (Denmark)
Gholampour, Amin; Sheshmani, Artan; Yau, Shing-Tung
We construct natural virtual fundamental classes for nested Hilbert schemes on a nonsingular projective surface S. This allows us to define new invariants of S that recover some of the known important cases such as Poincare invariants of Durr-Kabanov-Okonek and the stable pair invariants of Kool......-Thomas. In the case of the nested Hilbert scheme of points, we can express these invariants in terms of integrals over the products of Hilbert scheme of points on S, and relate them to the vertex operator formulas found by Carlsson-Okounkov. The virtual fundamental classes of the nested Hilbert schemes play a crucial...
The Hilbert's-Tenth-Problem Operator
Kramer, Ken; Miller, Russell
2017-01-01
For a ring $R$, Hilbert's Tenth Problem $HTP(R)$ is the set of polynomial equations over $R$, in several variables, with solutions in $R$. We view $HTP$ as an operator, mapping each set $W$ of prime numbers to $HTP(\\mathbb Z[W^{-1}])$, which is naturally viewed as a set of polynomials in $\\mathbb Z[X_1,X_2,\\ldots]$. For $W=\\emptyset$, it is a famous result of Matiyasevich, Davis, Putnam, and Robinson that the jump $\\emptyset~\\!'$ is Turing-equivalent to $HTP(\\mathbb Z)$. More generally, $HTP(...
Concerning the Hilbert 16th problem
Ilyashenko, Yu; Il'yashenko, Yu
1995-01-01
This book examines qualitative properties of vector fields in the plane, in the spirit of Hilbert's Sixteenth Problem. Two principal topics explored are bifurcations of limit cycles of planar vector fields and desingularization of singular points for individual vector fields and for analytic families of such fields. In addition to presenting important new developments in this area, this book contains an introductory paper which outlines the general context and describes connections between the papers in the volume. The book will appeal to researchers and graduate students working in the qualit
Ben Salem, Samira; Bacha, Khmais; Chaari, Abdelkader
2012-09-01
In this work we suggest an original fault signature based on an improved combination of Hilbert and Park transforms. Starting from this combination we can create two fault signatures: Hilbert modulus current space vector (HMCSV) and Hilbert phase current space vector (HPCSV). These two fault signatures are subsequently analysed using the classical fast Fourier transform (FFT). The effects of mechanical faults on the HMCSV and HPCSV spectrums are described, and the related frequencies are determined. The magnitudes of spectral components, relative to the studied faults (air-gap eccentricity and outer raceway ball bearing defect), are extracted in order to develop the input vector necessary for learning and testing the support vector machine with an aim of classifying automatically the various states of the induction motor. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.
Construction and deconstruction of single instanton Hilbert series
Energy Technology Data Exchange (ETDEWEB)
Hanany, Amihay; Kalveks, Rudolph [Theoretical Physics Group, The Blackett Laboratory, Imperial College London,Prince Consort Road, London SW7 2AZ (United Kingdom)
2015-12-17
Many methods exist for the construction of the Hilbert series describing the moduli spaces of instantons. We explore some of the underlying group theoretic relationships between these various constructions, including those based on the Coulomb branches and Higgs branches of SUSY quiver gauge theories, as well as those based on generating functions derivable from the Weyl Character Formula. We show how the character description of the reduced single instanton moduli space (“RSIMS') of any Classical or Exceptional group can be deconstructed faithfully in terms of characters or modified Hall-Littlewood polynomials of its regular semi-simple subgroups. We derive and utilise Highest Weight Generating (“HWG') functions, both for the characters of Classical or Exceptional groups and for the Hall-Littlewood polynomials of unitary groups. We illustrate how the root space data encoded in extended Dynkin diagrams corresponds to relationships between the Coulomb branches of quiver gauge theories for RSIMS and those for T(SU(N)) moduli spaces.
Empirical Mode Decomposition and Hilbert Spectral Analysis
Huang, Norden E.
1998-01-01
The difficult facing data analysis is the lack of method to handle nonlinear and nonstationary time series. Traditional Fourier-based analyses simply could not be applied here. A new method for analyzing nonlinear and nonstationary data has been developed. The key part is the Empirical Mode Decomposition (EMD) method with which any complicated data set can be decomposed into a finite and often small number of Intrinsic Mode Functions (IMF) that serve as the basis of the representation of the data. This decomposition method is adaptive, and, therefore, highly efficient. The IMFs admit well-behaved Hilbert transforms, and yield instantaneous energy and frequency as functions of time that give sharp identifications of imbedded structures. The final presentation of the results is an energy-frequency-time distribution, designated as the Hilbert Spectrum. Among the main conceptual innovations is the introduction of the instantaneous frequencies for complicated data sets, which eliminate the need of spurious harmonics to represent nonlinear and nonstationary signals. Examples from the numerical results of the classical nonlinear equation systems and data representing natural phenomena are given to demonstrate the power of this new method. The classical nonlinear system data are especially interesting, for they serve to illustrate the roles played by the nonlinear and nonstationary effects in the energy-frequency-time distribution.
Directory of Open Access Journals (Sweden)
Tong-Huei Chang
2009-01-01
Full Text Available We use a concept of abstract convexity to define the almost S-KKM𝒞 property, al-S-KKM𝒞(X,Y family, and almost Φ-spaces. We get some new approximate fixed point theorems and fixed point theorems in almost Φ-spaces. Our results extend some results of other authors.
Sur la tour de Hilbert de certains corps
Directory of Open Access Journals (Sweden)
Abdelmalek Azizi
2016-06-01
Full Text Available In this paper, we determine the first Hilbert $2$-class field for some quartic cyclic number fields ${\\mathrm k}$ and the Galois group of the second Hilbert $2$-class field of ${\\mathrm k}$ over ${\\mathrm k}$.
Neighbourhood Abstraction in GROOVE
Rensink, Arend; Zambon, Eduardo; De Lara, J.; Varro, D.
2011-01-01
Important classes of graph grammars have infinite state spaces and therefore cannot be verified with traditional model checking techniques. One way to address this problem is to perform graph abstraction, which allows us to generate a finite abstract state space that over-approximates the original
Matter tensor from the Hilbert variational principle
International Nuclear Information System (INIS)
Pandres, D. Jr.
1976-01-01
We consider the Hilbert variational principle which is conventionally used to derive Einstein's equations for the source-free gravitational field. We show that at least one version of the equivalence principle suggests an alternative way of performing the variation, resulting in a different set of Einstein equations with sources automatically present. This illustrates a technique which may be applied to any theory that is derived from a variational principle and that admits a gauge group. The essential point is that, if one first imposes a gauge condition and then performs the variation, one obtains field equations with source terms which do not appear if one first performs the variation and then imposes the gauge condition. A second illustration is provided by the variational principle conventionally used to derive Maxwell's equations for the source-free electromagnetic field. If one first imposes the Lorentz gauge condition and then performs the variation, one obtains Maxwell's equations with sources present
Hao, Xiao-Hu; Zhang, Gui-Jun; Zhou, Xiao-Gen; Yu, Xu-Feng
2016-01-01
To address the searching problem of protein conformational space in ab-initio protein structure prediction, a novel method using abstract convex underestimation (ACUE) based on the framework of evolutionary algorithm was proposed. Computing such conformations, essential to associate structural and functional information with gene sequences, is challenging due to the high-dimensionality and rugged energy surface of the protein conformational space. As a consequence, the dimension of protein conformational space should be reduced to a proper level. In this paper, the high-dimensionality original conformational space was converted into feature space whose dimension is considerably reduced by feature extraction technique. And, the underestimate space could be constructed according to abstract convex theory. Thus, the entropy effect caused by searching in the high-dimensionality conformational space could be avoided through such conversion. The tight lower bound estimate information was obtained to guide the searching direction, and the invalid searching area in which the global optimal solution is not located could be eliminated in advance. Moreover, instead of expensively calculating the energy of conformations in the original conformational space, the estimate value is employed to judge if the conformation is worth exploring to reduce the evaluation time, thereby making computational cost lower and the searching process more efficient. Additionally, fragment assembly and the Monte Carlo method are combined to generate a series of metastable conformations by sampling in the conformational space. The proposed method provides a novel technique to solve the searching problem of protein conformational space. Twenty small-to-medium structurally diverse proteins were tested, and the proposed ACUE method was compared with It Fix, HEA, Rosetta and the developed method LEDE without underestimate information. Test results show that the ACUE method can more rapidly and more
Empirical mode decomposition and Hilbert transforms for analysis of oil-film interferograms
International Nuclear Information System (INIS)
Chauhan, Kapil; Ng, Henry C H; Marusic, Ivan
2010-01-01
Oil-film interferometry is rapidly becoming the preferred method for direct measurement of wall shear stress in studies of wall-bounded turbulent flows. Although being widely accepted as the most accurate technique, it does have inherent measurement uncertainties, one of which is associated with determining the fringe spacing. This is the focus of this paper. Conventional analysis methods involve a certain level of user input and thus some subjectivity. In this paper, we consider empirical mode decomposition (EMD) and the Hilbert transform as an alternative tool for analyzing oil-film interferograms. In contrast to the commonly used Fourier-based techniques, this new method is less subjective and, as it is based on the Hilbert transform, is superior for treating amplitude and frequency modulated data. This makes it particularly robust to wide differences in the quality of interferograms
Slices to sums of adjoint orbits, the Atiyah-Hitchin manifold, and Hilbert schemes of points
Directory of Open Access Journals (Sweden)
Bielawski Roger
2017-02-01
Full Text Available We show that the regular Slodowy slice to the sum of two semisimple adjoint orbits of GL(n, ℂ is isomorphic to the deformation of the D2-singularity if n = 2, the Dancer deformation of the double cover of the Atiyah-Hitchin manifold if n = 3, and to the Atiyah-Hitchin manifold itself if n = 4. For higher n, such slices to the sum of two orbits, each having only two distinct eigenvalues, are either empty or biholomorphic to open subsets of the Hilbert scheme of points on one of the above surfaces. In particular, these open subsets of Hilbert schemes of points carry complete hyperkähler metrics. In the case of the double cover of the Atiyah-Hitchin manifold this metric turns out to be the natural L2-metric on a hyperkähler submanifold of the monopole moduli space.
Bosse, T.; Breebaart, L.; van Diggelen, J.; Neerincx, M.; Rosa, J.; Smets, N.
2017-01-01
Manned space missions are typically performed by teams composed of humans as well as technical systems and are situated in complex, dynamic and safety-critical domains. Intelligent electronic partners (ePartners) can play an important role here to support human-robot teams in their collaborative
L'influenza di David Hilbert nella teoria dei numeri
Directory of Open Access Journals (Sweden)
Roberto Dvornicich
2000-10-01
Full Text Available I contributi di Hilbert nella teoria dei numeri sono molteplici. Ci soffermeremo solo su due aspetti, che sembra abbiano influenzato in grande misura la teoria dei numeri nel ventesimo secolo: la teoria dei corpi di classe e il teorema di irriducibilità. Infine daremo brevi cenni sui problemi riguardanti la teoria dei numeri nella famosa lista dei 23 problemi di Hilbert.
Alternating Sunspot Area and Hilbert Transform Analysis
Directory of Open Access Journals (Sweden)
Bang-Yeop Kim
2011-12-01
Full Text Available We investigate the sunspot area data spanning from solar cycles 1 (March 1755 to 23 (December 2010 in time domain. For this purpose, we employ the Hilbert transform analysis method, which is used in the field of information theory. One of the most important advantages of this method is that it enables the simultaneous study of associations between the amplitude and the phase in various timescales. In this pilot study, we adopt the alternating sunspot area as a function of time, known as Bracewell transformation. We first calculate the instantaneous amplitude and the instantaneous phase. As a result, we confirm a ~22-year periodic behavior in the instantaneous amplitude. We also find that a behavior of the instantaneous amplitude with longer periodicities than the ~22-year periodicity can also be seen, though it is not as straightforward as the obvious ~22-year periodic behavior revealed by the method currently proposed. In addition to these, we note that the phase difference apparently correlates with the instantaneous amplitude. On the other hand, however, we cannot see any obvious association of the instantaneous frequency and the instantaneous amplitude. We conclude by briefly discussing the current status of development of an algorithm for the solar activity forecast based on the method presented, as this work is a part of that larger project.
On the Application of Hilbert Spectral Analysis for Climate Studies
Huang, Norden E.; Koblinsky, Chester J. (Technical Monitor)
2001-01-01
The Hilbert spectral analysis (Huang et al, 1998, Proceedings of the Royal Society of London, A 454, pp 903-995) consisted of two steps: First, the data has to be reduced into a finite number of Intrinsic Mode Function by the Empirical Mode Decomposition method, then the resulting Intrinsic Mode Functions are converted to time-frequency-energy distribution through Hilbert transform. In this approach, the Empirical Mode Functions served as the basis functions with which the data is expanded. This basis function is adaptive, and the decomposition is nonlinear. Furthermore, as the Hilbert transform is a singular transform, it retains a high degree of local information. The instantaneous frequency is determined by differentiation of the phase function; therefore, there is no restriction of the 'uncertainty principle' for all the time-frequency analysis resulting from a priori basis approach. With the adaptive basis and the instantaneous frequency, the Hilbert Spectral analysis can represent data from nonlinear and nonstationary processes without resorting to the harmonics. Another advantage of using instantaneous frequency is the ability to find out frequency from limited length of data, which is a critical problem in climate studies. As the processes driving the climate changes could be both nonlinear and nonstationary, the Hilbert Spectral Analysis could be of great use in examining the underlying mechanisms. A preliminary study based on the length of day data will be presented as example for the application of the Hilbert Spectral Analysis for climate study.
Fusion frames and G-frames in Banach spaces
Indian Academy of Sciences (India)
Fusion frames and -frames in Hilbert spaces are generalizations of frames, and frames were extended to Banach spaces. In this article we introduce fusion frames, -frames, Banach -frames in Banach spaces and we show that they share many useful properties with their corresponding notions in Hilbert spaces. We also ...
Stochastic Moyal product on the Wiener space
International Nuclear Information System (INIS)
Dito, Giuseppe; Leandre, Remi
2007-01-01
We propose a stochastic extension of deformation quantization on a Hilbert space. The Moyal product is defined in this context on the space of functionals belonging to all of the Sobolev spaces of the Malliavin calculus
Seizure classification in EEG signals utilizing Hilbert-Huang transform
Directory of Open Access Journals (Sweden)
Abdulhay Enas W
2011-05-01
Full Text Available Abstract Background Classification method capable of recognizing abnormal activities of the brain functionality are either brain imaging or brain signal analysis. The abnormal activity of interest in this study is characterized by a disturbance caused by changes in neuronal electrochemical activity that results in abnormal synchronous discharges. The method aims at helping physicians discriminate between healthy and seizure electroencephalographic (EEG signals. Method Discrimination in this work is achieved by analyzing EEG signals obtained from freely accessible databases. MATLAB has been used to implement and test the proposed classification algorithm. The analysis in question presents a classification of normal and ictal activities using a feature relied on Hilbert-Huang Transform. Through this method, information related to the intrinsic functions contained in the EEG signal has been extracted to track the local amplitude and the frequency of the signal. Based on this local information, weighted frequencies are calculated and a comparison between ictal and seizure-free determinant intrinsic functions is then performed. Methods of comparison used are the t-test and the Euclidean clustering. Results The t-test results in a P-value Conclusion An original tool for EEG signal processing giving physicians the possibility to diagnose brain functionality abnormalities is presented in this paper. The proposed system bears the potential of providing several credible benefits such as fast diagnosis, high accuracy, good sensitivity and specificity, time saving and user friendly. Furthermore, the classification of mode mixing can be achieved using the extracted instantaneous information of every IMF, but it would be most likely a hard task if only the average value is used. Extra benefits of this proposed system include low cost, and ease of interface. All of that indicate the usefulness of the tool and its use as an efficient diagnostic tool.
Completeness of Lyapunov Abstraction
DEFF Research Database (Denmark)
Wisniewski, Rafal; Sloth, Christoffer
2013-01-01
the vector field, which allows the generation of a complete abstraction. To compute the functions that define the subdivision of the state space in an algorithm, we formulate a sum of squares optimization problem. This optimization problem finds the best subdivisioning functions, with respect to the ability......This paper addresses the generation of complete abstractions of polynomial dynamical systems by timed automata. For the proposed abstraction, the state space is divided into cells by sublevel sets of functions. We identify a relation between these functions and their directional derivatives along...
Commuting nonselfadjoint operators in Hilbert space two independent studies
Livšic, Moshe S
1987-01-01
Classification of commuting non-selfadjoint operators is one of the most challenging problems in operator theory even in the finite-dimensional case. The spectral analysis of dissipative operators has led to a series of deep results in the framework of unitary dilations and characteristic operator functions. It has turned out that the theory has to be based on analytic functions on algebraic manifolds and not on functions of several independent variables as was previously believed. This follows from the generalized Cayley-Hamilton Theorem, due to M.S.Livsic: "Two commuting operators with finite dimensional imaginary parts are connected in the generic case, by a certain algebraic equation whose degree does not exceed the dimension of the sum of the ranges of imaginary parts." Such investigations have been carried out in two directions. One of them, presented by L.L.Waksman, is related to semigroups of projections of multiplication operators on Riemann surfaces. Another direction, which is presented here by M.S...
Explicit signal to noise ratio in reproducing kernel Hilbert spaces
DEFF Research Database (Denmark)
Gomez-Chova, Luis; Nielsen, Allan Aasbjerg; Camps-Valls, Gustavo
2011-01-01
This paper introduces a nonlinear feature extraction method based on kernels for remote sensing data analysis. The proposed approach is based on the minimum noise fraction (MNF) transform, which maximizes the signal variance while also minimizing the estimated noise variance. We here propose an a...... with PCA, MNF, KPCA, and the previous version of KMNF. Extracted features with the explicit KMNF also improve hyperspectral image classification....
Introduction to partial differential equations and Hilbert space methods
Gustafson, Karl E
1997-01-01
Easy-to-use text examines principal method of solving partial differential equations, 1st-order systems, computation methods, and much more. Over 600 exercises, with answers for many. Ideal for a 1-semester or full-year course.
On Nyman, Beurling and Baez-Duarte's Hilbert space reformulation ...
Indian Academy of Sciences (India)
an expert is usually defined to be a person who has the relevant piece of information.) Moreover, the main result in [2] is not the ... Recall that Riemann's zeta function is the analytic function defined on the half-plane {σ > 1} by the absolutely ... Our intention in this article is to point out that the entire gamut of these results is ...
On Nyman, Beurling and Baez-Duarte's Hilbert space reformulation ...
Indian Academy of Sciences (India)
The purpose of this little survey is to dis-entangle the resulting web of complications, and reveal the essential simplicity of the main results. Keywords. Riemann hypothesis ...... Surely a dramatically new and deep idea is called for. But then, as a wise man once said, it is fool-hardy to predict – specially the future! References.
Energy Technology Data Exchange (ETDEWEB)
Lu Lei, E-mail: llv1@crimson.ua.edu [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States); Stern, A., E-mail: astern@bama.ua.edu [Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States)
2012-01-21
We examine basis functions on momentum space for the three-dimensional Euclidean Snyder algebra. We argue that the momentum space is isomorphic to the SO(3) group manifold, and that the basis functions span either one of two Hilbert spaces. This implies the existence of two distinct lattice structures of space. Continuous rotations and translations are unitarily implementable on these lattices. - Highlights: {yields} Basis functions for the three-dimensional Snyder algebra span either one of two distinct Hilbert spaces. {yields} They imply the existence of two different lattice structures of space. {yields} Continuous translations and rotations are unitarily implementable on such lattices.
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.
Garrett, Paul B
2007-01-01
Designed for an advanced undergraduate- or graduate-level course, Abstract Algebra provides an example-oriented, less heavily symbolic approach to abstract algebra. The text emphasizes specifics such as basic number theory, polynomials, finite fields, as well as linear and multilinear algebra. This classroom-tested, how-to manual takes a more narrative approach than the stiff formalism of many other textbooks, presenting coherent storylines to convey crucial ideas in a student-friendly, accessible manner. An unusual feature of the text is the systematic characterization of objects by universal
African Journals Online (AJOL)
Abstract. Simple learning tools to improve clinical laboratory practical skills training. B Taye, BSc, MPH. Addis Ababa University, College of Health Sciences, Addis Ababa, ... concerns about the competence of medical laboratory science graduates. ... standardised practical learning guides and assessment checklists would.
African Journals Online (AJOL)
Abstract. Cyclic ovarian activity and plasma progesterone (P4) concentrations were assessed for 179 days in 5. (free grazing) and 6 (free grazing + high energy and protein-supplemented) normocyclic donkeys. In addition, plasma p4 and cortisol were measured in blood samples collected at J5·min intervals in the.
African Journals Online (AJOL)
cce
Abstract. Hemoglobin is a tetrameric protein which is able to dissociate into dimers. The dimers can in turn dissociate into tetramers. It has been found that dimers are more reactive than tetramers. The difference in the reactivity of these two species has been used to determine the tetramer- dimer dissociation constant of ...
Koenig, Robert; Maurer, Ueli; Tessaro, Stefano
2007-01-01
A quantum storage device differs radically from a conventional physical storage device. Its state can be set to any value in a certain (infinite) state space, but in general every possible read operation yields only partial information about the stored state. The purpose of this paper is to initiate the study of a combinatorial abstraction, called abstract storage device (ASD), which models deterministic storage devices with the property that only partial information about the state can be re...
Convolution on spaces of locally summable functions
Directory of Open Access Journals (Sweden)
Federica Andreano
2008-01-01
Full Text Available In this work we prove the existence of convolution on Marcinkiewicz spaces p(ℝ, 1≤p<∞, and, using pointwise approximate identities, we extend the classical definition of Hilbert transform to such spaces.
Inverses of new Hilbert-Pachpatte-type inequalities
Directory of Open Access Journals (Sweden)
Cheung Wing-Sum
2006-01-01
Full Text Available We establish a new inequality of Hilbert type for a finite double number of nonnegative sequences of real numbers and some interrelated results, which are inverse and general forms of Pachpatte's and Handley's results. An integral version and some interrelated results are also obtained. These results provide some new estimates on such types of inequalities.
AN EFFICIENT HILBERT AND INTEGER WAVELET TRANSFORM BASED VIDEO WATERMARKING
Directory of Open Access Journals (Sweden)
AGILANDEESWARI L.
2016-03-01
Full Text Available In this paper, an efficient, highly imperceptible, robust, and secure digital video watermarking technique for content authentication based on Hilbert transform in the Integer Wavelet Transform (IWT domain has been introduced. The Hilbert coefficients of gray watermark image are embedded into the cover video frames Hilbert coefficients on the 2-level IWT decomposed selected block on sub-bands using Principal Component Analysis (PCA technique. The authentication is achieved by using the digital signature mechanism. This mechanism is used to generate and embed a digital signature after embedding the watermarks. Since, the embedding process is done in Hilbert transform domain, the imperceptibility and the robustness of the watermark is greatly improved. At the receiver end, prior to the extraction of watermark, the originality of the content is verified through the authentication test. If the generated and received signature matches, it proves that the received content is original and performs the extraction process, otherwise deny the extraction process due to unauthenticated received content. The proposed method avoids typical degradations in the imperceptibility level of watermarked video in terms of Average Peak Signal – to – Noise Ratio (PSNR value of about 48db, while it is still providing better robustness against common video distortions such as frame dropping, averaging, and various image processing attacks such as noise addition, median filtering, contrast adjustment, and geometrical attacks such as, rotation and cropping in terms of Normalized Correlation Coefficient (NCC value of about nearly 1.
on differential operators on w 1,2 space and fredholm operators
African Journals Online (AJOL)
A selfadjoint differential operator defined over a closed and bounded interval on Sobolev space which is a dense linear subspace of a Hilbert space over the same interval is considered and shown to be a Fredholm operator with index zero. KEY WORDS: Sobolev space, Hilbert space, dense subspace, Fredholm operator
Li, Ping; Schloss, Benjamin; Follmer, D Jake
2017-10-01
In this article we report a computational semantic analysis of the presidential candidates' speeches in the two major political parties in the USA. In Study One, we modeled the political semantic spaces as a function of party, candidate, and time of election, and findings revealed patterns of differences in the semantic representation of key political concepts and the changing landscapes in which the presidential candidates align or misalign with their parties in terms of the representation and organization of politically central concepts. Our models further showed that the 2016 US presidential nominees had distinct conceptual representations from those of previous election years, and these patterns did not necessarily align with their respective political parties' average representation of the key political concepts. In Study Two, structural equation modeling demonstrated that reported political engagement among voters differentially predicted reported likelihoods of voting for Clinton versus Trump in the 2016 presidential election. Study Three indicated that Republicans and Democrats showed distinct, systematic word association patterns for the same concepts/terms, which could be reliably distinguished using machine learning methods. These studies suggest that given an individual's political beliefs, we can make reliable predictions about how they understand words, and given how an individual understands those same words, we can also predict an individual's political beliefs. Our study provides a bridge between semantic space models and abstract representations of political concepts on the one hand, and the representations of political concepts and citizens' voting behavior on the other.
International Nuclear Information System (INIS)
Ogievetsky, O.; Pillin, M.; Schmidke, W.B.; Wess, J.; Zumino, B.
1993-01-01
In this lecture I discuss the algebraic structure of a q-deformed four-vector space. It serves as a good example of quantizing Minkowski space. To give a physical interpretation of such a quantized Minkowski space we construct the Hilbert space representation and find that the relevant time and space operators have a discrete spectrum. Thus the q-deformed Minkowski space has a lattice structure. Nevertheless this lattice structure is compatible with the operation of q-deformed Lorentz transformations. The generators of the q-deformed Lorentz group can be represented as linear operators in the same Hilbert space. (orig.)
Behrndt, Jussi; Gesztesy, Fritz; Holden, Helge; Nichols, Roger
2016-09-01
We introduce a generalized index for certain meromorphic, unbounded, operator-valued functions. The class of functions is chosen such that energy parameter dependent Dirichlet-to-Neumann maps associated to uniformly elliptic partial differential operators, particularly, non-self-adjoint Schrödinger operators, on bounded Lipschitz domains, and abstract operator-valued Weyl-Titchmarsh M-functions and Donoghue-type M-functions corresponding to closed extensions of symmetric operators belong to it. The principal purpose of this paper is to prove index formulas that relate the difference of the algebraic multiplicities of the discrete eigenvalues of Robin realizations of non-self-adjoint Schrödinger operators, and more abstract pairs of closed operators in Hilbert spaces with the generalized index of the corresponding energy dependent Dirichlet-to-Neumann maps and abstract Weyl-Titchmarsh M-functions, respectively.
Unveiling signatures of interdecadal climate changes by Hilbert analysis
Zappalà, Dario; Barreiro, Marcelo; Masoller, Cristina
2017-04-01
A recent study demonstrated that, in a class of networks of oscillators, the optimal network reconstruction from dynamics is obtained when the similarity analysis is performed not on the original dynamical time series, but on transformed series obtained by Hilbert transform. [1] That motivated us to use Hilbert transform to study another kind of (in a broad sense) "oscillating" series, such as the series of temperature. Actually, we found that Hilbert analysis of SAT (Surface Air Temperature) time series uncovers meaningful information about climate and is therefore a promising tool for the study of other climatological variables. [2] In this work we analysed a large dataset of SAT series, performing Hilbert transform and further analysis with the goal of finding signs of climate change during the analysed period. We used the publicly available ERA-Interim dataset, containing reanalysis data. [3] In particular, we worked on daily SAT time series, from year 1979 to 2015, in 16380 points arranged over a regular grid on the Earth surface. From each SAT time series we calculate the anomaly series and also, by using the Hilbert transform, we calculate the instantaneous amplitude and instantaneous frequency series. Our first approach is to calculate the relative variation: the difference between the average value on the last 10 years and the average value on the first 10 years, divided by the average value over all the analysed period. We did this calculations on our transformed series: frequency and amplitude, both with average values and standard deviation values. Furthermore, to have a comparison with an already known analysis methods, we did these same calculations on the anomaly series. We plotted these results as maps, where the colour of each site indicates the value of its relative variation. Finally, to gain insight in the interpretation of our results over real SAT data, we generated synthetic sinusoidal series with various levels of additive noise. By applying
International Nuclear Information System (INIS)
Morell, Morell; Todorovik, Olivija; Dimitrov, Dobri
2004-01-01
anthropogenic pressures and international shared water. Here are the 320 abstracts proposed by authors and accepted by the Scientific Committee. More than 200 papers are presented during the Conference on 8 topics related to Hydrology, Climatology and Hydro biology: - Climate and Environment; - Hydrological regimes and water balances; - Droughts and Floods; -Integrated Water Resources Management; -Water bodies Protection and Eco hydrology; -Lakes; -Information Systems for decision support; -Hydrological modelling. Papers relevant to INIS are indexed separately
T^{\\sigma}_{\\rho}(G) Theories and Their Hilbert Series
Cremonesi, Stefano; Mekareeya, Noppadol; Zaffaroni, Alberto
2015-01-01
We give an explicit formula for the Higgs and Coulomb branch Hilbert series for the class of 3d N=4 superconformal gauge theories T^{\\sigma}_{\\rho}(G) corresponding to a set of D3 branes ending on NS5 and D5-branes, with or without O3 planes. Here G is a classical group, \\sigma is a partition of G and \\rho a partition of the dual group G^\\vee. In deriving such a formula we make use of the recently discovered formula for the Hilbert series of the quantum Coulomb branch of N=4 superconformal theories. The result can be expressed in terms of a generalization of a class of symmetric functions, the Hall-Littlewood polynomials, and can be interpreted in mathematical language in terms of localization. We mainly consider the case G=SU(N) but some interesting results are also given for orthogonal and symplectic groups.
Directionality fields generated by a local Hilbert transform
Ahmed, W. W.; Herrero, R.; Botey, M.; Hayran, Z.; Kurt, H.; Staliunas, K.
2018-03-01
We propose an approach based on a local Hilbert transform to design non-Hermitian potentials generating arbitrary vector fields of directionality, p ⃗(r ⃗) , with desired shapes and topologies. We derive a local Hilbert transform to systematically build such potentials by modifying background potentials (being either regular or random, extended or localized). We explore particular directionality fields, for instance in the form of a focus to create sinks for probe fields (which could help to increase absorption at the sink), or to generate vortices in the probe fields. Physically, the proposed directionality fields provide a flexible mechanism for dynamical shaping and precise control over probe fields leading to novel effects in wave dynamics.
Milling gate vibrations analysis via Hilbert-Huang transform
Directory of Open Access Journals (Sweden)
Litak Grzegorz
2017-01-01
Full Text Available The study aimed at identification of the milling gate modal parameters: natural frequencies and mode shapes, in order to establish the working range free from resonant areas. The evaluation was performed under exploitation loads, generated in the course of the milling process. System responses, in the form of the acceleration time histories, were analysed with the application of the Hilbert-Huang method data analysis. Selection of this method was motivated by the fact that it does not require stationarity of the analysed and provides information about nonlinearities in vibration empirical modes. In contrast to classical nonlinear system identification methods, the Hilbert-Huang method does not require measurements of excitations acting on the system of interest nor linear system dynamic behaviour in a broad frequency range around any operating point.
Parameterized hilbert-type integral inequalities in the whole plane.
Huang, Qiliang; Wu, Shanhe; Yang, Bicheng
2014-01-01
By the use of the way of real analysis, we estimate the weight functions and give some new Hilbert-type integral inequalities in the whole plane with nonhomogeneous kernels and multiparameters. The constant factors related to the hypergeometric function and the beta function are proved to be the best possible. We also consider the equivalent forms, the reverses, and some particular cases in the homogeneous kernels.
Von Neuman representations on self-dual Hilbert W* moduli
International Nuclear Information System (INIS)
Frank, M.
1987-01-01
Von Neumann algebras M of bounded operators on self-dual Hilbert W* moduli H possessing a cyclic-separating element x-bar in H are considered. The close relation of them to certain real subspaces of H is established. Under the supposition that the underlying W*-algebra is commutative, a Tomita-Takesaki type theorem is stated. The natural cone in H arising from the pair (M, x-bar) is investigated and its properties are obtained
How were the Hilbert-Einstein equations discovered?
International Nuclear Information System (INIS)
Logunov, Anatolii A; Mestvirishvili, Mirian A; Petrov, Vladimir A
2004-01-01
The ways in which Albert Einstein and David Hilbert independently arrived at the gravitational field equations are traced. A critical analysis is presented of a number of papers in which the history of the derivation of the equations is viewed in a way that 'radically differs from the standard point of view'. The conclusions of these papers are shown to be totally unfounded. (from the history of physics)
Geometry and experience: Einstein's 1921 paper and Hilbert's axiomatic system
International Nuclear Information System (INIS)
De Gandt, Francois
2006-01-01
In his 1921 paper Geometrie und Erfahrung, Einstein decribes the new epistemological status of geometry, divorced from any intuitive or a priori content. He calls that 'axiomatics', following Hilbert's theoretical developments on axiomatic systems, which started with the stimulus given by a talk by Hermann Wiener in 1891 and progressed until the Foundations of geometry in 1899. Difficult questions arise: how is a theoretical system related to an intuitive empirical content?
Einstein Meets Hilbert: At the Crossroads of Physics and Mathematics
Rowe, David E.
One of the most famous episodes in the early history of general relativity involves the ``race'' in November 1915 between Albert Einstein and David Hilbert to uncover the ``correct'' form for the ten gravitational field equations. In light of recent archival findings, however, this story now has become a topic of renewed interest and controversy among historians of physics and mathematics. Drawing on recent studies and newly found sources, the present essay takes up this familiar tale from a new perspective, one that has seldom received due attention in the standard literature, namely, the mathematical issues at the heart of Einstein's theory. Told from this angle, the leading actors are Einstein's collaborator Marcel Grossmann, his critic Tullio Levi-Civita, his competitor David Hilbert, and several other mathematicians, many of them connected with Hilbert's Göttingen colleagues such as Hermann Weyl, Felix Klein, and Emmy Noether. As Einstein was the first to admit, Göttingen was far more important than Berlin as an active center for research in general relativity. Any account which, like this one, tries to understand both the actions and motives of the leading players must confront the problem of interpreting the rather sparse documentary evidence available. The interpretation offered herein, whatever its merits, aims first and foremost to show how mathematical issues deeply permeated the early history of general relativity.
International Nuclear Information System (INIS)
Bianchi, E.; Bender, C.; Culetu, H.; Fried, H.; Grossmann, A.; Hofmann, R.; Le Bellac, M.; Martinetti, P.; Muller, B.; Patras, F.; Raffaeli, B.; Vitting Andersen, J.
2013-01-01
The object of this workshop is to consolidate and publicize new efforts in non-perturbative field theories. This year the presentations deal with quantum gravity, non-commutative geometry, fat-tailed wave-functions, strongly coupled field theories, space-times two time-like dimensions, and multiplicative renormalization. A presentation is dedicated to the construction of a nucleon-nucleon potential from an analytical, non-perturbative gauge invariant QCD. This document gathers the abstracts of the presentations
Hilbert's sixth problem and the failure of the Boltzmann to Euler limit.
Slemrod, Marshall
2018-04-28
This paper addresses the main issue of Hilbert's sixth problem, namely the rigorous passage of solutions to the mesoscopic Boltzmann equation to macroscopic solutions of the Euler equations of compressible gas dynamics. The results of the paper are that (i) in general Hilbert's program will fail because of the appearance of van der Waals-Korteweg capillarity terms in a macroscopic description of motion of a gas, and (ii) the van der Waals-Korteweg theory itself might satisfy Hilbert's quest for a map from the 'atomistic view' to the laws of motion of continua.This article is part of the theme issue 'Hilbert's sixth problem'. © 2018 The Author(s).
The Hilbert series of N=1SO(N{sub c}) and Sp(N{sub c}) SQCD, Painleve VI and integrable systems
Energy Technology Data Exchange (ETDEWEB)
Basor, Estelle, E-mail: ebasor@aimath.or [American Institute of Mathematics, 360 Portage Avenue, Palo Alto, CA 9430 (United States); Chen Yang, E-mail: ychen@imperial.ac.uk [Department of Mathematics, Imperial College London, 180 Queen' s Gates, London SW7 2BZ (United Kingdom); Department of Mathematics, Faculty of Science and Technology, University of Macau, Av. Padre Tomas Pereira, Taipa, Macau (China); Mekareeya, Noppadol, E-mail: noppadol@mpp.mpg.de [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Muenchen (Germany)
2012-07-21
We present a novel approach for computing the Hilbert series of 4d N=1 supersymmetric QCD with SO(N{sub c}) and Sp(N{sub c}) gauge groups. It is shown that such Hilbert series can be recast in terms of determinants of Hankel matrices. With the aid of results from random matrix theory, such Hankel determinants can be evaluated both exactly and asymptotically. Several new results on Hilbert series for general numbers of colours and flavours are thus obtained in this paper. We show that the Hilbert series give rise to families of rational solutions, with palindromic numerators, to the Painleve VI equations. Due to the presence of such Painleve equations, there exist integrable Hamiltonian systems that describe the moduli spaces of SO(N{sub c}) and Sp(N{sub c}) SQCD. To each system, we explicitly state the corresponding Hamiltonian and family of elliptic curves. It turns out that such elliptic curves take the same form as the Seiberg-Witten curves for 4d N=2SU(2) gauge theory with 4 flavours.
Time average vibration fringe analysis using Hilbert transformation
International Nuclear Information System (INIS)
Kumar, Upputuri Paul; Mohan, Nandigana Krishna; Kothiyal, Mahendra Prasad
2010-01-01
Quantitative phase information from a single interferogram can be obtained using the Hilbert transform (HT). We have applied the HT method for quantitative evaluation of Bessel fringes obtained in time average TV holography. The method requires only one fringe pattern for the extraction of vibration amplitude and reduces the complexity in quantifying the data experienced in the time average reference bias modulation method, which uses multiple fringe frames. The technique is demonstrated for the measurement of out-of-plane vibration amplitude on a small scale specimen using a time average microscopic TV holography system.
Estimaciones para el Teorema de Ceros de Hilbert
Sombra, Martín
1998-01-01
Se introduce una nueva noción de altura para variedades afines. Esta noción extiende al caso de una variedad arbitraria la noción de altura de Weil de una variedad de dimensión cero y la noción de altura de una hipersuperficie. Se obtiene una Desigualdad de Bézout Aritmética para la intersección de variedades. Se estudian luego los aspectos cuantitativos del Teorema de Ceros de Hilbert. La noción de altura de variedades se aplica para obtener nuevas cotas para los grados y para las alturas de...
Pattern-Based Graph Abstraction
Rensink, Arend; Zambon, Eduardo; Ehrig, H; Engels, G.; Kreowski, H.J.; Rozenberg, G.
We present a new abstraction technique for the exploration of graph transformation systems with infinite state spaces. This technique is based on patterns, simple graphs describing structures of interest that should be preserved by the abstraction. Patterns are collected into pattern graphs, layered
Partial inner product spaces theory and applications
Antoine, Jean-Pierre
2009-01-01
Partial Inner Product (PIP) Spaces are ubiquitous, e.g. Rigged Hilbert spaces, chains of Hilbert or Banach spaces (such as the Lebesgue spaces Lp over the real line), etc. In fact, most functional spaces used in (quantum) physics and in signal processing are of this type. The book contains a systematic analysis of PIP spaces and operators defined on them. Numerous examples are described in detail and a large bibliography is provided. Finally, the last chapters cover the many applications of PIP spaces in physics and in signal/image processing, respectively. As such, the book will be useful both for researchers in mathematics and practitioners of these disciplines.
Multisymplectic unified formalism for Einstein-Hilbert gravity
Gaset, Jordi; Román-Roy, Narciso
2018-03-01
We present a covariant multisymplectic formulation for the Einstein-Hilbert model of general relativity. As it is described by a second-order singular Lagrangian, this is a gauge field theory with constraints. The use of the unified Lagrangian-Hamiltonian formalism is particularly interesting when it is applied to these kinds of theories, since it simplifies the treatment of them, in particular, the implementation of the constraint algorithm, the retrieval of the Lagrangian description, and the construction of the covariant Hamiltonian formalism. In order to apply this algorithm to the covariant field equations, they must be written in a suitable geometrical way, which consists of using integrable distributions, represented by multivector fields of a certain type. We apply all these tools to the Einstein-Hilbert model without and with energy-matter sources. We obtain and explain the geometrical and physical meaning of the Lagrangian constraints and we construct the multimomentum (covariant) Hamiltonian formalisms in both cases. As a consequence of the gauge freedom and the constraint algorithm, we see how this model is equivalent to a first-order regular theory, without gauge freedom. In the case of the presence of energy-matter sources, we show how some relevant geometrical and physical characteristics of the theory depend on the type of source. In all the cases, we obtain explicitly multivector fields which are solutions to the gravitational field equations. Finally, a brief study of symmetries and conservation laws is done in this context.
Applications of Hilbert Spectral Analysis for Speech and Sound Signals
Huang, Norden E.
2003-01-01
A new method for analyzing nonlinear and nonstationary data has been developed, and the natural applications are to speech and sound signals. The key part of the method is the Empirical Mode Decomposition method with which any complicated data set can be decomposed into a finite and often small number of Intrinsic Mode Functions (IMF). An IMF is defined as any function having the same numbers of zero-crossing and extrema, and also having symmetric envelopes defined by the local maxima and minima respectively. The IMF also admits well-behaved Hilbert transform. This decomposition method is adaptive, and, therefore, highly efficient. Since the decomposition is based on the local characteristic time scale of the data, it is applicable to nonlinear and nonstationary processes. With the Hilbert transform, the Intrinsic Mode Functions yield instantaneous frequencies as functions of time, which give sharp identifications of imbedded structures. This method invention can be used to process all acoustic signals. Specifically, it can process the speech signals for Speech synthesis, Speaker identification and verification, Speech recognition, and Sound signal enhancement and filtering. Additionally, as the acoustical signals from machinery are essentially the way the machines are talking to us. Therefore, the acoustical signals, from the machines, either from sound through air or vibration on the machines, can tell us the operating conditions of the machines. Thus, we can use the acoustic signal to diagnosis the problems of machines.
On using the Hilbert transform for blind identification of complex modes: A practical approach
Antunes, Jose; Debut, Vincent; Piteau, Pilippe; Delaune, Xavier; Borsoi, Laurent
2018-01-01
The modal identification of dynamical systems under operational conditions, when subjected to wide-band unmeasured excitations, is today a viable alternative to more traditional modal identification approaches based on processing sets of measured FRFs or impulse responses. Among current techniques for performing operational modal identification, the so-called blind identification methods are the subject of considerable investigation. In particular, the SOBI (Second-Order Blind Identification) method was found to be quite efficient. SOBI was originally developed for systems with normal modes. To address systems with complex modes, various extension approaches have been proposed, in particular: (a) Using a first-order state-space formulation for the system dynamics; (b) Building complex analytic signals from the measured responses using the Hilbert transform. In this paper we further explore the latter option, which is conceptually interesting while preserving the model order and size. Focus is on applicability of the SOBI technique for extracting the modal responses from analytic signals built from a set of vibratory responses. The novelty of this work is to propose a straightforward computational procedure for obtaining the complex cross-correlation response matrix to be used for the modal identification procedure. After clarifying subtle aspects of the general theoretical framework, we demonstrate that the correlation matrix of the analytic responses can be computed through a Hilbert transform of the real correlation matrix, so that the actual time-domain responses are no longer required for modal identification purposes. The numerical validation of the proposed technique is presented based on time-domain simulations of a conceptual physical multi-modal system, designed to display modes ranging from normal to highly complex, while keeping modal damping low and nearly independent of the modal complexity, and which can prove very interesting in test bench
Abstracts and Abstracting in Knowledge Discovery.
Pinto, Maria; Lancaster, F. W.
1999-01-01
Presents various levels of criteria for judging the quality of abstracts and abstracting. Requirements for abstracts to be read by humans are compared with requirements for those to be searched by computer. Concludes that the wide availability of complete text in electronic form does not reduce the value of abstracts for information retrieval.…
PAIR FRAMES IN HILBERT C∗−MODULES 1. Introduction Frames ...
Indian Academy of Sciences (India)
53
and sufficient conditions for a Hilbert C∗−module to admit a pair frame with a symbol and two standard Bessel sequences. Moreover by generalizing some of the results obtained for Bessel multipliers in Hilbert C∗−modules to pair frames and considering the stability of pair frames under invertible operators, we construct.
Lin, Chin-Feng; Zhu, Jin-De
2012-03-01
Hilbert-Huang transformation, wavelet transformation, and Fourier transformation are the principal time-frequency analysis methods. These transformations can be used to discuss the frequency characteristics of linear and stationary signals, the time-frequency features of linear and non-stationary signals, the time-frequency features of non-linear and non-stationary signals, respectively. The Hilbert-Huang transformation is a combination of empirical mode decomposition and Hilbert spectral analysis. The empirical mode decomposition uses the characteristics of signals to adaptively decompose them to several intrinsic mode functions. Hilbert transforms are then used to transform the intrinsic mode functions into instantaneous frequencies, to obtain the signal's time-frequency-energy distributions and features. Hilbert-Huang transformation-based time-frequency analysis can be applied to natural physical signals such as earthquake waves, winds, ocean acoustic signals, mechanical diagnosis signals, and biomedical signals. In previous studies, we examined Hilbert-Huang transformation-based time-frequency analysis of the electroencephalogram FPI signals of clinical alcoholics, and 'sharp I' wave-based Hilbert-Huang transformation time-frequency features. In this paper, we discuss the application of Hilbert-Huang transformation-based time-frequency analysis to biomedical signals, such as electroencephalogram, electrocardiogram signals, electrogastrogram recordings, and speech signals.
VILCHES, Emilio
2017-01-01
This thesis is dedicated to the study of differential inclusions involving normal cones of nonregular sets in Hilbert spaces. In particular, we are interested in the sweeping process and its variants. The sweeping process is a constrained differential inclusion involving normal cones which appears naturally in several applications such as elastoplasticity, electrical circuits, hysteresis, crowd motion, etc.This work is divided conceptually in three parts: Study of positively alpha-far sets, e...
International Nuclear Information System (INIS)
1990-05-01
This bibliography contains citations concerning studies and conceptual designs of nuclear space power reactors to generate electric power for space missions. The citations cover the technology, safety aspects, and policy considerations. (This updated bibliography contains 280 citations, 172 of which are new entries to the previous edition.)
Terahertz bandwidth all-optical Hilbert transformers based on long-period gratings.
Ashrafi, Reza; Azaña, José
2012-07-01
A novel, all-optical design for implementing terahertz (THz) bandwidth real-time Hilbert transformers is proposed and numerically demonstrated. An all-optical Hilbert transformer can be implemented using a uniform-period long-period grating (LPG) with a properly designed amplitude-only grating apodization profile, incorporating a single π-phase shift in the middle of the grating length. The designed LPG-based Hilbert transformers can be practically implemented using either fiber-optic or integrated-waveguide technologies. As a generalization, photonic fractional Hilbert transformers are also designed based on the same optical platform. In this general case, the resulting LPGs have multiple π-phase shifts along the grating length. Our numerical simulations confirm that all-optical Hilbert transformers capable of processing arbitrary optical signals with bandwidths well in the THz range can be implemented using feasible fiber/waveguide LPG designs.
Characterizing R-duality in Banach spaces
DEFF Research Database (Denmark)
Christensen, Ole; Xiao, Xiang Chun; Zhu, Yu Can
2013-01-01
R-duals of certain sequences in Hilbert spaces were introduced by Casazza, Kutyniok and Lammers in 2004 and later generalized to Banach spaces by Xiao and Zhu. In this paper we provide some characterizations of R-dual sequences in Banach spaces.......R-duals of certain sequences in Hilbert spaces were introduced by Casazza, Kutyniok and Lammers in 2004 and later generalized to Banach spaces by Xiao and Zhu. In this paper we provide some characterizations of R-dual sequences in Banach spaces....
Regularization methods in Banach spaces
Schuster, Thomas; Hofmann, Bernd; Kazimierski, Kamil S
2012-01-01
Regularization methods aimed at finding stable approximate solutions are a necessary tool to tackle inverse and ill-posed problems. Usually the mathematical model of an inverse problem consists of an operator equation of the first kind and often the associated forward operator acts between Hilbert spaces. However, for numerous problems the reasons for using a Hilbert space setting seem to be based rather on conventions than on an approprimate and realistic model choice, so often a Banach space setting would be closer to reality. Furthermore, sparsity constraints using general Lp-norms or the B
A Modal-Logic Based Graph Abstraction
Bauer, J.; Boneva, I.B.; Kurban, M.E.; Rensink, Arend; Ehrig, H; Heckel, R.; Rozenberg, G.; Taentzer, G.
2008-01-01
Infinite or very large state spaces often prohibit the successful verification of graph transformation systems. Abstract graph transformation is an approach that tackles this problem by abstracting graphs to abstract graphs of bounded size and by lifting application of productions to abstract
A Generalized Demodulation and Hilbert Transform Based Signal Decomposition Method
Directory of Open Access Journals (Sweden)
Zhi-Xiang Hu
2017-01-01
Full Text Available This paper proposes a new signal decomposition method that aims to decompose a multicomponent signal into monocomponent signal. The main procedure is to extract the components with frequencies higher than a given bisecting frequency by three steps: (1 the generalized demodulation is used to project the components with lower frequencies onto negative frequency domain, (2 the Hilbert transform is performed to eliminate the negative frequency components, and (3 the inverse generalized demodulation is used to obtain the signal which contains components with higher frequencies only. By running the procedure recursively, all monocomponent signals can be extracted efficiently. A comprehensive derivation of the decomposition method is provided. The validity of the proposed method has been demonstrated by extensive numerical analysis. The proposed method is also applied to decompose the dynamic strain signal of a cable-stayed bridge and the echolocation signal of a bat.
Public channel cryptography: chaos synchronization and Hilbert's tenth problem.
Kanter, Ido; Kopelowitz, Evi; Kinzel, Wolfgang
2008-08-22
The synchronization process of two mutually delayed coupled deterministic chaotic maps is demonstrated both analytically and numerically. The synchronization is preserved when the mutually transmitted signals are concealed by two commutative private filters, a convolution of the truncated time-delayed output signals or some powers of the delayed output signals. The task of a passive attacker is mapped onto Hilbert's tenth problem, solving a set of nonlinear Diophantine equations, which was proven to be in the class of NP-complete problems [problems that are both NP (verifiable in nondeterministic polynomial time) and NP-hard (any NP problem can be translated into this problem)]. This bridge between nonlinear dynamics and NP-complete problems opens a horizon for new types of secure public-channel protocols.
Application of Arbitrary-Order Hilbert Spectral Analysis to Passive Scalar Turbulence
International Nuclear Information System (INIS)
Huang, Y X; Lu, Z M; Liu, Y L; Schmitt, F G; Gagne, Y
2011-01-01
In previous work [Huang et al., PRE 82, 26319, 2010], we found that the passive scalar turbulence field maybe less intermittent than what we believed before. Here we apply the same method, namely arbitrary-order Hilbert spectral analysis, to a passive scalar (temperature) time series with a Taylor's microscale Reynolds number Re λ ≅ 3000. We find that with increasing Reynolds number, the discrepancy of scaling exponents between Hilbert ξ θ (q) and Kolmogorov-Obukhov-Corrsin (KOC) theory is increasing, and consequently the discrepancy between Hilbert and structure function could disappear at infinite Reynolds number.
Detection of the third and fourth heart sounds using Hilbert-Huang transform
Directory of Open Access Journals (Sweden)
Tseng Yi-Li
2012-02-01
Full Text Available Abstract Background The third and fourth heart sound (S3 and S4 are two abnormal heart sound components which are proved to be indicators of heart failure during diastolic period. The combination of using diastolic heart sounds with the standard ECG as a measurement of ventricular dysfunction may improve the noninvasive diagnosis and early detection of myocardial ischemia. Methods In this paper, an adaptive method based on time-frequency analysis is proposed to detect the presence of S3 and S4. Heart sound signals during diastolic periods were analyzed with Hilbert-Huang Transform (HHT. A discrete plot of maximal instantaneous frequency and its amplitude was generated and clustered. S3 and S4 were recognized by the clustered points, and performance of the method was further enhanced by period definition and iteration tracking. Results Using the proposed method, S3 and S4 could be detected adaptively in a same method. 90.3% of heart sound cycles with S3 were detected using our method, 9.6% were missed, and 9.6% were false positive. 94% of S4 were detected using our method, 5.5% were missed, and 16% were false positive. Conclusions The proposed method is adaptive for detecting low-amplitude and low-frequency S3 and S4 simultaneously compared with previous detection methods, which would be practical in primary care.
Chang Tong-Huei; Chen Chi-Ming; Huang Yueh-Hung
2009-01-01
We use a concept of abstract convexity to define the almost - property, al- - family, and almost -spaces. We get some new approximate fixed point theorems and fixed point theorems in almost -spaces. Our results extend some results of other authors.
From Abstract Art to Abstracted Artists
Directory of Open Access Journals (Sweden)
Romi Mikulinsky
2016-11-01
Full Text Available What lineage connects early abstract films and machine-generated YouTube videos? Hans Richter’s famous piece Rhythmus 21 is considered to be the first abstract film in the experimental tradition. The Webdriver Torso YouTube channel is composed of hundreds of thousands of machine-generated test patterns designed to check frequency signals on YouTube. This article discusses geometric abstraction vis-à-vis new vision, conceptual art and algorithmic art. It argues that the Webdriver Torso is an artistic marvel indicative of a form we call mathematical abstraction, which is art performed by computers and, quite possibly, for computers.
IEEE conference record -- Abstracts
Energy Technology Data Exchange (ETDEWEB)
1994-01-01
This conference covers the following areas: computational plasma physics; vacuum electronic; basic phenomena in fully ionized plasmas; plasma, electron, and ion sources; environmental/energy issues in plasma science; space plasmas; plasma processing; ball lightning/spherical plasma configurations; plasma processing; fast wave devices; magnetic fusion; basic phenomena in partially ionized plasma; dense plasma focus; plasma diagnostics; basic phenomena in weakly ionized gases; fast opening switches; MHD; fast z-pinches and x-ray lasers; intense ion and electron beams; laser-produced plasmas; microwave plasma interactions; EM and ETH launchers; solid state plasmas and switches; intense beam microwaves; and plasmas for lighting. Separate abstracts were prepared for 416 papers in this conference.
IEEE conference record -- Abstracts
International Nuclear Information System (INIS)
Anon.
1994-01-01
This conference covers the following areas: computational plasma physics; vacuum electronic; basic phenomena in fully ionized plasmas; plasma, electron, and ion sources; environmental/energy issues in plasma science; space plasmas; plasma processing; ball lightning/spherical plasma configurations; plasma processing; fast wave devices; magnetic fusion; basic phenomena in partially ionized plasma; dense plasma focus; plasma diagnostics; basic phenomena in weakly ionized gases; fast opening switches; MHD; fast z-pinches and x-ray lasers; intense ion and electron beams; laser-produced plasmas; microwave plasma interactions; EM and ETH launchers; solid state plasmas and switches; intense beam microwaves; and plasmas for lighting. Separate abstracts were prepared for 416 papers in this conference
International Nuclear Information System (INIS)
1975-01-01
Abstracts of 25 papers presented at the congress are given. The abstracts cover various topics including radiotherapy, radiopharmaceuticals, radioimmunoassay, health physics, radiation protection and nuclear medicine
Munari, U.
2015-06-01
(Abstract only) A huge, worldwide effort is underway to reconstruct the structure, kinematics and evolution of our Galaxy with optical spectroscopic techniques, which provide radial velocities and individual chemical abundances in addition to derive fundamental stellar parameters like surface temperature and gravity. RAVE has used for ten years (2003-2013) the 6dF 150-fiber positioner at the 1.3-meter UK Schmidt telescope in Siding Spring, ESO-Gaia has hundreds of nights allocated at the VLT telescopes in Chile with UVES and GIRAFFE multi-fiber instruments, GALAH has been allocated 400 nights in five years with the 400-fiber HERMES spectrograph at the 4-meter Australian telescope. Common to the millions of stars targeted by these surveys (over the range 10 < V < 16 mag) is the lack of suitable, multi-band, accurate optical photometry. In this talk, I review the fundamental role played by APASS in providing such missing photometric information for the stars targeted by these gigantic spectroscopic surveys. The APASS BVgri data are fundamental to support the spectroscopic effort, for example to constrain (when modelled together with 2MASS infrared JHK photometry) the stellar temperature. The APASS data are also crucial in fixing the interstellar reddening and the distance to the target stars, and their importance will be further expanded when APASS ultraviolet (u) and far red (z,Y) magnitudes will become available, as well the unsaturated APASS extension to brighter stars so that most of the bright spectroscopic standards will become within photometric reach.
Application of Hilbert-Huang Transform in Generating Spectrum-Compatible Earthquake Time Histories
Ni, Shun-Hao; Xie, Wei-Chau; Pandey, Mahesh
2011-01-01
Spectrum-compatible earthquake time histories have been widely used for seismic analysis and design. In this paper, a data processing method, Hilbert-Huang transform, is applied to generate earthquake time histories compatible with the target seismic design spectra based on multiple actual earthquake records. Each actual earthquake record is decomposed into several components of time-dependent amplitude and frequency by Hilbert-Huang transform. The spectrum-compatible earthquake time history ...
Integrated reconfigurable photonic filters based on interferometric fractional Hilbert transforms.
Sima, C; Cai, B; Liu, B; Gao, Y; Yu, Y; Gates, J C; Zervas, M N; Smith, P G R; Liu, D
2017-10-01
In this paper, we present integrated reconfigurable photonic filters using fractional Hilbert transformers (FrHTs) and optical phase tuning structure within the silica-on-silicon platform. The proposed structure, including grating-based FrHTs, an X-coupler, and a pair of thermal tuning filaments, is fabricated through the direct UV grating writing technique. The thermal tuning effect is realized by the controllable microheaters located on the two arms of the X-coupler. We investigate the 200 GHz maximum bandwidth photonic FrHTs based on apodized planar Bragg gratings, and analyze the reflection spectrum responses. Through device integration and thermal modulation, the device could operate as photonic notch filters with 5 GHz linewidth and controllable single sideband suppression filters with measured 12 dB suppression ratio. A 50 GHz instantaneous frequency measuring system using this device is also schematically proposed and analyzed with potential 3 dB measurement improvement. The device could be configured with these multiple functions according to need. The reconfigurable structure has great potential in ultrafast all-optical signal processing fields.
Pomeron interactions from the Einstein-Hilbert action
Iatrakis, Ioannis; Ramamurti, Adith; Shuryak, Edward
2016-08-01
Holographic models of QCD, collectively known as anti-de Sitter/QCD, have been proven useful in deriving several properties of hadrons. One particular feature well reproduced by such models is the Regge trajectories, both for mesons and glueballs. We focus on scalar and tensor glueballs and derive an effective theory for the Pomeron by analytic continuation along the leading trajectory from the tensor glueball. It then follows that the Pomeron, as the tensor glueball itself, should possess a two-index polarization tensor, inherited from the graviton. The three-graviton interaction is deduced from the Einstein-Hilbert action. Using this structure in the cross section of double-Pomeron production of the tensor glueball, we calculate certain angular distributions of production and compare them with those from the CERN WA102 experiment. We find that the agreement is very good for the f2(2300 ) tensor glueball candidate. At the same time, other tensor states—such as f2(1270 ) and f2'(1520 ) —have completely different distributions, which we interpret as a consequence of the fact that they are not glueballs and thus, in our model, unrelated to the gravitational excitations, which are dual to spin-2 glueballs.
Energy Technology Data Exchange (ETDEWEB)
Schaffner, B.; Cattin, R. [Meteotest, Berne (Switzerland)
2005-07-01
This report presents an abstract of the development work carried out by the Swiss meteorology specialists METEOTEST as part of a project carried out together with the Swiss wind-energy organisation 'Suisse Eole'. The framework for the project is the EU Interreg IIIB Alpine Space Programme, a European Community Initiative Programme funded by the European Regional Development Fund. The project investigated the use of digital relief-analysis. The series of reports describes the development and use of a basic information system to aid the investigation of the technical, legal and socio-economical conditions for the use of wind energy in the alpine area. This report presents an abstract of the work done as part of the Work Package 7 of the Alpine Windharvest project.
Anastasi, Robert F.; Madaras, Eric I.
2005-01-01
Terahertz NDE is being examined as a method to inspect the adhesive bond-line of Space Shuttle tiles for defects. Terahertz signals are generated and detected, using optical excitation of biased semiconductors with femtosecond laser pulses. Shuttle tile samples were manufactured with defects that included repair regions unbond regions, and other conditions that occur in Shuttle structures. These samples were inspected with a commercial terahertz NDE system that scanned a tile and generated a data set of RF signals. The signals were post processed to generate C-scan type images that are typically seen in ultrasonic NDE. To improve defect visualization the Hilbert-Huang Transform, a transform that decomposes a signal into oscillating components called intrinsic mode functions, was applied to test signals identified as being in and out of the defect regions and then on a complete data set. As expected with this transform, the results showed that the decomposed low-order modes correspond to signal noise while the high-order modes correspond to low frequency oscillations in the signal and mid-order modes correspond to local signal oscillations. The local oscillations compare well with various reflection interfaces and the defect locations in the original signal.
International Nuclear Information System (INIS)
Bonora, Loriano; Bytsenko, Andrey; Elizalde, Emilio
2012-01-01
This review paper contains a concise introduction to highest weight representations of infinite-dimensional Lie algebras, vertex operator algebras and Hilbert schemes of points, together with their physical applications to elliptic genera of superconformal quantum mechanics and superstring models. The common link of all these concepts and of the many examples considered in this paper is to be found in a very important feature of the theory of infinite-dimensional Lie algebras: the modular properties of the characters (generating functions) of certain representations. The characters of the highest weight modules represent the holomorphic parts of the partition functions on the torus for the corresponding conformal field theories. We discuss the role of the unimodular (and modular) groups and the (Selberg-type) Ruelle spectral functions of hyperbolic geometry in the calculation of elliptic genera and associated q-series. For mathematicians, elliptic genera are commonly associated with new mathematical invariants for spaces, while for physicists elliptic genera are one-loop string partition function. (Therefore, they are applicable, for instance, to topological Casimir effect calculations.) We show that elliptic genera can be conveniently transformed into product expressions, which can then inherit the homology properties of appropriate polygraded Lie algebras. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical in honour of Stuart Dowker’s 75th birthday devoted to ‘Applications of zeta functions and other spectral functions in mathematics and physics’. (review)
Coherent states in the fermionic Fock space
International Nuclear Information System (INIS)
Oeckl, Robert
2015-01-01
We construct the coherent states in the sense of Gilmore and Perelomov for the fermionic Fock space. Our treatment is from the outset adapted to the infinite-dimensional case. The fermionic Fock space becomes in this way a reproducing kernel Hilbert space of continuous holomorphic functions. (paper)
Seizure classification in EEG signals utilizing Hilbert-Huang transform.
Oweis, Rami J; Abdulhay, Enas W
2011-05-24
Classification method capable of recognizing abnormal activities of the brain functionality are either brain imaging or brain signal analysis. The abnormal activity of interest in this study is characterized by a disturbance caused by changes in neuronal electrochemical activity that results in abnormal synchronous discharges. The method aims at helping physicians discriminate between healthy and seizure electroencephalographic (EEG) signals. Discrimination in this work is achieved by analyzing EEG signals obtained from freely accessible databases. MATLAB has been used to implement and test the proposed classification algorithm. The analysis in question presents a classification of normal and ictal activities using a feature relied on Hilbert-Huang Transform. Through this method, information related to the intrinsic functions contained in the EEG signal has been extracted to track the local amplitude and the frequency of the signal. Based on this local information, weighted frequencies are calculated and a comparison between ictal and seizure-free determinant intrinsic functions is then performed. Methods of comparison used are the t-test and the Euclidean clustering. The t-test results in a P-value method is also contrasted against the Multivariate Empirical Mode Decomposition that reaches 80% accuracy. Comparison results strengthen the contribution of this paper not only from the accuracy point of view but also with respect to its fast response and ease to use. An original tool for EEG signal processing giving physicians the possibility to diagnose brain functionality abnormalities is presented in this paper. The proposed system bears the potential of providing several credible benefits such as fast diagnosis, high accuracy, good sensitivity and specificity, time saving and user friendly. Furthermore, the classification of mode mixing can be achieved using the extracted instantaneous information of every IMF, but it would be most likely a hard task if only the
Abstract Objects in a Metaphysical Perspective
Directory of Open Access Journals (Sweden)
Aleksandr Kulieshov
2018-02-01
Full Text Available The article presents an unconventional although not absolutely unprecedented view on abstract objects defending the position of metaphysical realism. It is argued that abstract objects taken in purely ontological sense are the forms of objects. The forms possess some common characteristics of abstract objects, they can exist not in physical space and time and play a grounding role in their relation to concrete objects. It is stated that commonly discussed abstract objects – properties, kinds, mathematical objects – are forms.
International Nuclear Information System (INIS)
1975-01-01
Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled:Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Physics Education; SANCGASS; Astronomy; Plasma Physics; Physics in Industry; Applied and General Physics
Wavelet Based Hilbert Transform with Digital Design and Application to QCM-SS Watermarking
Directory of Open Access Journals (Sweden)
S. P. Maity
2008-04-01
Full Text Available In recent time, wavelet transforms are used extensively for efficient storage, transmission and representation of multimedia signals. Hilbert transform pairs of wavelets is the basic unit of many wavelet theories such as complex filter banks, complex wavelet and phaselet etc. Moreover, Hilbert transform finds various applications in communications and signal processing such as generation of single sideband (SSB modulation, quadrature carrier multiplexing (QCM and bandpass representation of a signal. Thus wavelet based discrete Hilbert transform design draws much attention of researchers for couple of years. This paper proposes an (i algorithm for generation of low computation cost Hilbert transform pairs of symmetric filter coefficients using biorthogonal wavelets, (ii approximation to its rational coefficients form for its efficient hardware realization and without much loss in signal representation, and finally (iii development of QCM-SS (spread spectrum image watermarking scheme for doubling the payload capacity. Simulation results show novelty of the proposed Hilbert transform design and its application to watermarking compared to existing algorithms.
Sima, Chaotan; Gates, J C; Holmes, C; Mennea, P L; Zervas, M N; Smith, P G R
2013-09-01
Terahertz bandwidth photonic Hilbert transformers are proposed and experimentally demonstrated. The integrated device is fabricated via a direct UV grating writing technique in a silica-on-silicon platform. The photonic Hilbert transformer operates at bandwidths of up to 2 THz (~16 nm) in the telecom band, a 10-fold greater bandwidth than any previously reported experimental approaches. Achieving this performance requires detailed knowledge of the system transfer function of the direct UV grating writing technique; this allows improved linearity and yields terahertz bandwidth Bragg gratings with improved spectral quality. By incorporating a flat-top reflector and Hilbert grating with a waveguide coupler, an ultrawideband all-optical single-sideband filter is demonstrated.
Recent Developments of Hilbert-Type Discrete and Integral Inequalities with Applications
Directory of Open Access Journals (Sweden)
Lokenath Debnath
2012-01-01
Full Text Available This paper deals with recent developments of Hilbert-type discrete and integral inequalities by introducing kernels, weight functions, and multiparameters. Included are numerous generalizations, extensions, and refinements of Hilbert-type inequalities involving many special functions such as beta, gamma, logarithm, trigonometric, hyper-bolic, Bernoulli's functions and Bernoulli's numbers, Euler's constant, zeta function, and hypergeometric functions with many applications. Special attention is given to many equivalent inequalities and to conditions under which the constant factors involved in inequalities are the best possible. Many particular cases of Hilbert-type inequalities are presented with numerous applications. A large number of major books and recent research papers published during 2009–2012 are included to stimulate new interest in future study and research.
Casazza, Peter G
1989-01-01
This monograph provides a structure theory for the increasingly important Banach space discovered by B.S. Tsirelson. The basic construction should be accessible to graduate students of functional analysis with a knowledge of the theory of Schauder bases, while topics of a more advanced nature are presented for the specialist. Bounded linear operators are studied through the use of finite-dimensional decompositions, and complemented subspaces are studied at length. A myriad of variant constructions are presented and explored, while open questions are broached in almost every chapter. Two appendices are attached: one dealing with a computer program which computes norms of finitely-supported vectors, while the other surveys recent work on weak Hilbert spaces (where a Tsirelson-type space provides an example).
Foundations of phase-space quantum mechanics
International Nuclear Information System (INIS)
Guz, W.
1984-01-01
In the present paper a general concept of a phase-space representation of the ordinary Hilbert-space quantum theory is formulated, and then, by using some elementary facts of functional analysis, several equivalent forms of that concept are analyzed. Several important physical examples are presented in Section 3 of the paper. (author)
Differential operators on Hermite Sobolev spaces
Indian Academy of Sciences (India)
In this paper, we compute the Hilbert space adjoint * of the derivative operator on the Hermite Sobolev spaces S q . We use this calculation to give a different proof of the 'monotonicity inequality' for a class of differential operators (, ) for which the inequality was proved in Infin. Dimens. Anal. Quantum Probab. Relat.
Nice surjections on spaces of operators
Indian Academy of Sciences (India)
A bounded linear operator is said to be nice if its adjoint preserves extreme points of the dual unit ball. Motivated by a description due to Labuschagne and Mascioni [9] of such maps for the space of compact operators on a Hilbert space, in this article we consider a description of nice surjections on K ( X , Y ) for Banach ...
Compilation of Theses Abstracts
National Research Council Canada - National Science Library
2005-01-01
This publication contains unclassified/unrestricted abstracts of classified or restricted theses submitted for the degrees of Doctor of Philosophy, Master of Business Administration, Master of Science...
Computational Abstraction Steps
DEFF Research Database (Denmark)
Thomsen, Lone Leth; Thomsen, Bent; Nørmark, Kurt
2010-01-01
and class instantiations. Our teaching experience shows that many novice programmers find it difficult to write programs with abstractions that materialise to concrete objects later in the development process. The contribution of this paper is the idea of initiating a programming process by creating......In this paper we discuss computational abstraction steps as a way to create class abstractions from concrete objects, and from examples. Computational abstraction steps are regarded as symmetric counterparts to computational concretisation steps, which are well-known in terms of function calls...
Cutting force response in milling of Inconel: analysis by wavelet and Hilbert-Huang Transforms
Directory of Open Access Journals (Sweden)
Grzegorz Litak
Full Text Available We study the milling process of Inconel. By continuously increasing the cutting depth we follow the system response and appearance of oscillations of larger amplitude. The cutting force amplitude and frequency analysis has been done by means of wavelets and Hilbert-Huang transform. We report that in our system the force oscillations are closely related to the rotational motion of the tool and advocate for a regenerative mechanism of chatter vibrations. To identify vibrations amplitudes occurrence in time scale we apply wavelet and Hilbert-Huang transforms.
Nuclear medicine. Abstracts; Nuklearmedizin 2000. Abstracts
Energy Technology Data Exchange (ETDEWEB)
Anon.
2000-07-01
This issue of the journal contains the abstracts of the 183 conference papers as well as 266 posters presented at the conference. Subject fields covered are: Neurology, psychology, oncology, pediatrics, radiopharmacy, endocrinology, EDP, measuring equipment and methods, radiological protection, cardiology, and therapy. (orig./CB) [German] Die vorliegende Zeitschrift enthaelt die Kurzfassungen der 183 auf der Tagung gehaltenen Vortraege sowie der 226 praesentierten Poster, die sich mit den folgenden Themen befassten: Neurologie, Psychiatrie, Onkologie, Paediatrie, Radiopharmazie, Endokrinologie, EDV, Messtechnik, Strahlenschutz, Kardiologie sowie Therapie. (MG)
Zhuang, L.; Beeker, Willem; Beeker, W.P.; Leinse, Arne; Heideman, Rene; Roeloffzen, C.G.H.
2012-01-01
We propose and demonstrate a wideband photonic fractional Hilbert transformer implemented using a ring resonator-based optical all-pass filter. The full programmability of the ring resonators allows variable and arbitrary fractional order of the Hilbert transformer. The implemented all-pass filter
Quantitative Hahn-Banach Theorems and Isometric Extensions forWavelet and Other Banach Spaces
Directory of Open Access Journals (Sweden)
Sergey Ajiev
2013-05-01
Full Text Available We introduce and study Clarkson, Dol’nikov-Pichugov, Jacobi and mutual diameter constants reflecting the geometry of a Banach space and Clarkson, Jacobi and Pichugov classes of Banach spaces and their relations with James, self-Jung, Kottman and Schäffer constants in order to establish quantitative versions of Hahn-Banach separability theorem and to characterise the isometric extendability of Hölder-Lipschitz mappings. Abstract results are further applied to the spaces and pairs from the wide classes IG and IG+ and non-commutative Lp-spaces. The intimate relation between the subspaces and quotients of the IG-spaces on one side and various types of anisotropic Besov, Lizorkin-Triebel and Sobolev spaces of functions on open subsets of an Euclidean space defined in terms of differences, local polynomial approximations, wavelet decompositions and other means (as well as the duals and the lp-sums of all these spaces on the other side, allows us to present the algorithm of extending the main results of the article to the latter spaces and pairs. Special attention is paid to the matter of sharpness. Our approach is quasi-Euclidean in its nature because it relies on the extrapolation of properties of Hilbert spaces and the study of 1-complemented subspaces of the spaces under consideration.
DEFF Research Database (Denmark)
Brock-Nannestad, Taus; Schürmann, Carsten
2012-01-01
indefinitely, finding neither a proof nor a disproof of a given subgoal. In this paper we characterize a family of truth-preserving abstractions from intuitionistic first-order logic to the monadic fragment of classical first-order logic. Because they are truthful, these abstractions can be used to disprove...
Alter, David; Grenache, David G; Bosler, David S; Karcher, Raymond E; Nichols, James; Rajadhyaksha, Aparna; Camelo-Piragua, Sandra; Rauch, Carol; Huddleston, Brent J; Frank, Elizabeth L; Sluss, Patrick M; Lewandrowski, Kent; Eichhorn, John H; Hall, Janet E; Rahman, Saud S; McPherson, Richard A; Kiechle, Frederick L; Hammett-Stabler, Catherine; Pierce, Kristin A; Kloehn, Erica A; Thomas, Patricia A; Walts, Ann E; Madan, Rashna; Schlesinger, Kathie; Nawgiri, Ranjana; Bhutani, Manoop; Kanber, Yonca; Abati, Andrea; Atkins, Kristen A; Farrar, Robert; Gopez, Evelyn Valencerina; Jhala, Darshana; Griffin, Sonya; Jhala, Khushboo; Jhala, Nirag; Bentz, Joel S; Emerson, Lyska; Chadwick, Barbara E; Barroeta, Julieta E; Baloch, Zubair W; Collins, Brian T; Middleton, Owen L; Davis, Gregory G; Haden-Pinneri, Kathryn; Chu, Albert Y; Keylock, Joren B; Ramoso, Robert; Thoene, Cynthia A; Stewart, Donna; Pierce, Arand; Barry, Michelle; Aljinovic, Nika; Gardner, David L; Barry, Michelle; Shields, Lisa B E; Arnold, Jack; Stewart, Donna; Martin, Erica L; Rakow, Rex J; Paddock, Christopher; Zaki, Sherif R; Prahlow, Joseph A; Stewart, Donna; Shields, Lisa B E; Rolf, Cristin M; Falzon, Andrew L; Hudacki, Rachel; Mazzella, Fermina M; Bethel, Melissa; Zarrin-Khameh, Neda; Gresik, M Vicky; Gill, Ryan; Karlon, William; Etzell, Joan; Deftos, Michael; Karlon, William J; Etzell, Joan E; Wang, Endi; Lu, Chuanyi M; Manion, Elizabeth; Rosenthal, Nancy; Wang, Endi; Lu, Chuanyi M; Tang, Patrick; Petric, Martin; Schade, Andrew E; Hall, Geraldine S; Oethinger, Margret; Hall, Geraldine; Picton, Avis R; Hoang, Linda; Imperial, Miguel Ranoa; Kibsey, Pamela; Waites, Ken; Duffy, Lynn; Hall, Geraldine S; Salangsang, Jo-Anne M; Bravo, Lulette Tricia C; Oethinger, Margaret D; Veras, Emanuela; Silva, Elvia; Vicens, Jimena; Silva, Elvio; Keylock, Joren; Hempel, James; Rushing, Elizabeth; Posligua, Lorena E; Deavers, Michael T; Nash, Jason W; Basturk, Olca; Perle, Mary Ann; Greco, Alba; Lee, Peng; Maru, Dipen; Weydert, Jamie Allen; Stevens, Todd M; Brownlee, Noel A; Kemper, April E; Williams, H James; Oliverio, Brock J; Al-Agha, Osama M; Eskue, Kyle L; Newlands, Shawn D; Eltorky, Mahmoud A; Puri, Puja K; Royer, Michael C; Rush, Walter L; Tavora, Fabio; Galvin, Jeffrey R; Franks, Teri J; Carter, James Elliot; Kahn, Andrea Graciela; Lozada Muñoz, Luis R; Houghton, Dan; Land, Kevin J; Nester, Theresa; Gildea, Jacob; Lefkowitz, Jerry; Lacount, Rachel A; Thompson, Hannis W; Refaai, Majed A; Quillen, Karen; Lopez, Ana Ortega; Goldfinger, Dennis; Muram, Talia; Thompson, Hannis
2009-02-01
The following abstracts are compiled from Check Sample exercises published in 2008. These peer-reviewed case studies assist laboratory professionals with continuing medical education and are developed in the areas of clinical chemistry, cytopathology, forensic pathology, hematology, microbiology, surgical pathology, and transfusion medicine. Abstracts for all exercises published in the program will appear annually in AJCP.
International Nuclear Information System (INIS)
1976-01-01
Abstracts of the papers given at the conference are presented. The abstracts are arranged under sessions entitled: Theoretical Physics; Nuclear Physics; Solid State Physics; Spectroscopy; Plasma Physics; Solar-Terrestrial Physics; Astrophysics and Astronomy; Radioastronomy; General Physics; Applied Physics; Industrial Physics
GIBS Geospatial Data Abstraction Library (GDAL)
National Aeronautics and Space Administration — GDAL is an open source translator library for raster geospatial data formats that presents a single abstract data model to the calling application for all supported...
An abstract machine for module replacement
Walton, Chris; Krl, Dilsun; Gilmore, Stephen
1998-01-01
In this paper we define an abstract machine model for the mλ typed intermediate language. This abstract machine is used to give a formal description of the operation of run-time module replacement from the programming language Dynamic ML. The essential technical device which we employ for module replacement is a modification of two-space copying garbage collection.
Bounded Rationality of Generalized Abstract Fuzzy Economies
Directory of Open Access Journals (Sweden)
Lei Wang
2014-01-01
Full Text Available By using a nonlinear scalarization technique, the bounded rationality model M for generalized abstract fuzzy economies in finite continuous spaces is established. Furthermore, by using the model M, some new theorems for structural stability and robustness to (λ,ϵ-equilibria of generalized abstract fuzzy economies are proved.
Frame transforms, star products and quantum mechanics on phase space
International Nuclear Information System (INIS)
Aniello, P; Marmo, G; Man'ko, V I
2008-01-01
Using the notions of frame transform and of square integrable projective representation of a locally compact group G, we introduce a class of isometries (tight frame transforms) from the space of Hilbert-Schmidt operators in the carrier Hilbert space of the representation into the space of square integrable functions on the direct product group G x G. These transforms have remarkable properties. In particular, their ranges are reproducing kernel Hilbert spaces endowed with a suitable 'star product' which mimics, at the level of functions, the original product of operators. A 'phase space formulation' of quantum mechanics relying on the frame transforms introduced in the present paper, and the link of these maps with both the Wigner transform and the wavelet transform are discussed
Homborg, A.M.; Westing, E.P.M.; Tinga, Tiedo; Zhang, X; Oonincx, P.J.; Ferrari, G.M.; de Wit, J.H.W.; Mol, J.M.C.
2013-01-01
Hilbert spectra, calculated with the Hilbert–Huang transform, are presented here as an analysis technique for the characterization of electrochemical noise data in corrosion studies. A highly detailed decomposition of the original current and potential data is provided in time and frequency
International Nuclear Information System (INIS)
Chau Ling-Lie; Ge Mo-Lin; Teh, Rosy.
1984-09-01
The Baecklund Transformations and the hidden symmetry algebra for Self-Dual Yang-Mills Equations, Landau-Lifshitz equations and the Extended Super Yang-Mills fields (N>2) are discussed on the base of the Regular Riemann-Hilbert Transform and the linearization equations. (author)
Lagrangian single-particle turbulent statistics through the Hilbert-Huang transform
Huang, Y.; Biferale, L.; Calzavarini, E.; Sun, Chao; Toschi, F.
2013-01-01
The Hilbert-Huang transform is applied to analyze single-particle Lagrangian velocity data from numerical simulations of hydrodynamic turbulence. The velocity trajectory is described in terms of a set of intrinsic mode functions C i (t) and of their instantaneous frequency ω i (t) . On the basis of
Hilbert isometries and maximal deviation preserving maps on JB-algebras
Roelands, Mark; Wortel, Marten
2017-01-01
In this paper we characterize the surjective linear variation norm isometries on JB-algebras. Variation norm isometries are precisely the maps that preserve the maximal deviation, the quantum analogue of the standard deviation, which plays an important role in quantum statistics. Consequently, we characterize the Hilbert's metric isometries on cones in JB-algebras.
International Nuclear Information System (INIS)
2000-01-01
the document is a collection of the science meeting abstracts in the fields of nuclear physics, medical sciences, chemistry, agriculture, environment, engineering, material sciences different aspects of energy and presents research done in 2000 in these fields
The deleuzian abstract machines
DEFF Research Database (Denmark)
Werner Petersen, Erik
2005-01-01
To most people the concept of abstract machines is connected to the name of Alan Turing and the development of the modern computer. The Turing machine is universal, axiomatic and symbolic (E.g. operating on symbols). Inspired by Foucault, Deleuze and Guattari extended the concept of abstract...... machines to singular, non-axiomatic and diagrammatic machines. That is: Machines which constitute becomings. This presentation gives a survey of the development of the concept of abstract machines in the philosophy of Deleuze and Guatari and the function of these abstract machines in the creation of works...... of art. From Difference and Repetition to Anti-Oedipus, the machines are conceived as binary machines based on the exclusive or inclusive use respectively of the three syntheses: conexa, disjuncta and conjuncta. The machines have a twofold embedment: In the desiring-production and in the social...
Mathematical games, abstract games
Neto, Joao Pedro
2013-01-01
User-friendly, visually appealing collection offers both new and classic strategic board games. Includes abstract games for two and three players and mathematical games such as Nim and games on graphs.
Seizure classification in EEG signals utilizing Hilbert-Huang transform
Oweis, Rami J; Abdulhay, Enas W
2011-01-01
Abstract Background Classification method capable of recognizing abnormal activities of the brain functionality are either brain imaging or brain signal analysis. The abnormal activity of interest in this study is characterized by a disturbance caused by changes in neuronal electrochemical activity that results in abnormal synchronous discharges. The method aims at helping physicians discriminate between healthy and seizure electroencephalographic (EEG) signals. Method Discrimination in this ...
Introduction to abstract algebra
Smith, Jonathan D H
2008-01-01
Taking a slightly different approach from similar texts, Introduction to Abstract Algebra presents abstract algebra as the main tool underlying discrete mathematics and the digital world. It helps students fully understand groups, rings, semigroups, and monoids by rigorously building concepts from first principles. A Quick Introduction to Algebra The first three chapters of the book show how functional composition, cycle notation for permutations, and matrix notation for linear functions provide techniques for practical computation. The author also uses equivalence relations to introduc
Abstracts of contributed papers
Energy Technology Data Exchange (ETDEWEB)
1994-08-01
This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.
IEEE conference record--Abstracts
Energy Technology Data Exchange (ETDEWEB)
1992-01-01
The following topics were covered in this meeting: basic plasma phenomena and plasma waves; plasma diagnostics; space plasma diagnostics; magnetic fusion; electron, ion and plasma sources; intense electron and ion beams; intense beam microwaves; fast wave M/W devices; microwave plasma interactions; plasma focus; ultrafast Z-pinches; plasma processing; electrical gas discharges; fast opening switches; magnetohydrodynamics; electromagnetic and electrothermal launchers; x-ray lasers; computational plasma science; solid state plasmas and switches; environmental/energy issues in plasma science; vacuum electronics; plasmas for lighting; gaseous electronics; and ball lightning and other spherical plasmas. Separate abstracts were prepared for 278 papers of this conference.
Noncycling mappings and best proximity pair results in Hilbert and ...
African Journals Online (AJOL)
A new class of noncyclic mappings, called generalized noncyclic relatively nonexpansive, is introduced and used to study the existence of best proximity pairs in the setting of uniformly convex Banach spaces. We also obtain a weak convergence theorem for noncyclic relatively nonexpansive mappings in the setting of ...
Metacognition and abstract reasoning.
Markovits, Henry; Thompson, Valerie A; Brisson, Janie
2015-05-01
The nature of people's meta-representations of deductive reasoning is critical to understanding how people control their own reasoning processes. We conducted two studies to examine whether people have a metacognitive representation of abstract validity and whether familiarity alone acts as a separate metacognitive cue. In Study 1, participants were asked to make a series of (1) abstract conditional inferences, (2) concrete conditional inferences with premises having many potential alternative antecedents and thus specifically conducive to the production of responses consistent with conditional logic, or (3) concrete problems with premises having relatively few potential alternative antecedents. Participants gave confidence ratings after each inference. Results show that confidence ratings were positively correlated with logical performance on abstract problems and concrete problems with many potential alternatives, but not with concrete problems with content less conducive to normative responses. Confidence ratings were higher with few alternatives than for abstract content. Study 2 used a generation of contrary-to-fact alternatives task to improve levels of abstract logical performance. The resulting increase in logical performance was mirrored by increases in mean confidence ratings. Results provide evidence for a metacognitive representation based on logical validity, and show that familiarity acts as a separate metacognitive cue.
Abstract Expression Grammar Symbolic Regression
Korns, Michael F.
This chapter examines the use of Abstract Expression Grammars to perform the entire Symbolic Regression process without the use of Genetic Programming per se. The techniques explored produce a symbolic regression engine which has absolutely no bloat, which allows total user control of the search space and output formulas, which is faster, and more accurate than the engines produced in our previous papers using Genetic Programming. The genome is an all vector structure with four chromosomes plus additional epigenetic and constraint vectors, allowing total user control of the search space and the final output formulas. A combination of specialized compiler techniques, genetic algorithms, particle swarm, aged layered populations, plus discrete and continuous differential evolution are used to produce an improved symbolic regression sytem. Nine base test cases, from the literature, are used to test the improvement in speed and accuracy. The improved results indicate that these techniques move us a big step closer toward future industrial strength symbolic regression systems.
Asghari, Mohammad H; Azaña, José
2009-02-01
A simple all-fiber design for implementing an all-optical temporal Hilbert transformer is proposed and numerically demonstrated. We show that an all-optical Hilbert transformer can be implemented using a uniform-period fiber Bragg grating (FBG) with a properly designed amplitude-only grating apodization profile incorporating a single pi phase shift in the middle of the grating length. All-optical Hilbert transformers capable of processing arbitrary optical waveforms with bandwidths up to a few hundreds of gigahertz can be implemented using feasible FBGs.
DEFF Research Database (Denmark)
Robering, Klaus
2014-01-01
Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which these obj......Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which...
DEFF Research Database (Denmark)
Sergey, Ilya; Devriese, Dominique; Might, Matthew
2013-01-01
-insensitive analysis. To achieve this unification, we develop a systematic method for transforming a concrete semantics into a monadically-parameterized abstract machine. Changing the monad changes the behavior of the machine. By changing the monad, we recover a spectrum of machines—from the original concrete...
International Nuclear Information System (INIS)
Cessac, B.; Bianchi, E.; Bellon, M.; Fried, H.; Krajewski, T.; Schubert, C.; Barre, J.; Hofmann, R.; Muller, B.; Raffaelli, B.
2014-01-01
The object of this Workshop is to consolidate and publicize new efforts in non perturbative-like Field Theories, relying in Functional Methods, Renormalization Group, and Dyson-Schwinger Equations. A presentation deals with effective vertices and photon-photon scattering in SU(2) Yang-Mills thermodynamics. This document gathers the abstracts of the presentations
2002 NASPSA Conference Abstracts.
Journal of Sport & Exercise Psychology, 2002
2002-01-01
Contains abstracts from the 2002 conference of the North American Society for the Psychology of Sport and Physical Activity. The publication is divided into three sections: the preconference workshop, "Effective Teaching Methods in the Classroom;" symposia (motor development, motor learning and control, and sport psychology); and free…
DEFF Research Database (Denmark)
Fortescue, Michael David
The main thesis of this book is that abstraction, far from being confined to higher formsof cognition, language and logical reasoning, has actually been a major driving forcethroughout the evolution of creatures with brains. It is manifest in emotive as well as rationalthought. Wending its way th...
Composing Interfering Abstract Protocols
2016-04-01
Tecnologia , Universidade Nova de Lisboa, Caparica, Portugal. This document is a companion technical report of the paper, “Composing Interfering Abstract...a Ciência e Tecnologia (Portuguese Foundation for Science and Technology) through the Carnegie Mellon Portugal Program under grant SFRH / BD / 33765
Le Grice, Malcolm
A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…
Seismic Consequence Abstraction
International Nuclear Information System (INIS)
Gross, M.
2004-01-01
The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274])
Seismic Consequence Abstraction
Energy Technology Data Exchange (ETDEWEB)
M. Gross
2004-10-25
The primary purpose of this model report is to develop abstractions for the response of engineered barrier system (EBS) components to seismic hazards at a geologic repository at Yucca Mountain, Nevada, and to define the methodology for using these abstractions in a seismic scenario class for the Total System Performance Assessment - License Application (TSPA-LA). A secondary purpose of this model report is to provide information for criticality studies related to seismic hazards. The seismic hazards addressed herein are vibratory ground motion, fault displacement, and rockfall due to ground motion. The EBS components are the drip shield, the waste package, and the fuel cladding. The requirements for development of the abstractions and the associated algorithms for the seismic scenario class are defined in ''Technical Work Plan For: Regulatory Integration Modeling of Drift Degradation, Waste Package and Drip Shield Vibratory Motion and Seismic Consequences'' (BSC 2004 [DIRS 171520]). The development of these abstractions will provide a more complete representation of flow into and transport from the EBS under disruptive events. The results from this development will also address portions of integrated subissue ENG2, Mechanical Disruption of Engineered Barriers, including the acceptance criteria for this subissue defined in Section 2.2.1.3.2.3 of the ''Yucca Mountain Review Plan, Final Report'' (NRC 2003 [DIRS 163274]).
DEFF Research Database (Denmark)
2014-01-01
Verbs do often take arguments of quite different types. In an orthodox type-theoretic framework this results in an extreme polysemy of many verbs. In this article, it is shown that this unwanted consequence can be avoided when a theory of "abstract objects" is adopted according to which these obj...
International Nuclear Information System (INIS)
1987-01-01
The conference proceedings contain 152 abstracts of presented papers relating to various aspects of personnel dosimetry, the dosimetry of the working and living environment, various types of dosemeters and spectrometers, the use of radionuclides in various industrial fields, the migration of radionuclides on Czechoslovak territory after the Chernobyl accident, theoretical studies of some parameters of ionizing radiation detectors, and their calibration. (M.D.)
I. Boot (Inge)
2010-01-01
textabstractThe aim of the dissertation was to investigate the Conceptual Metaphor Theory (CMT, Lakoff & Johnson, 1980, 1999).The CMT proposes that abstract concepts are partly structured by concrete concepts through the mechanism of metaphorical mapping. In Chapter 2 we wanted to investigate the
Energy Technology Data Exchange (ETDEWEB)
NONE
2015-04-01
The volume contains the abstracts of the SPR (society for pediatric radiology) 2015 meeting covering the following issues: fetal imaging, muscoskeletal imaging, cardiac imaging, chest imaging, oncologic imaging, tools for process improvement, child abuse, contrast enhanced ultrasound, image gently - update of radiation dose recording/reporting/monitoring - meaningful or useless meaning?, pediatric thoracic imaging, ALARA.
Reflective Abstraction and Representation.
Lewin, Philip
Piaget's theory of reflective abstraction can supplement cognitive science models of representation by specifying both the act of construction and the component steps through which knowers pass as they acquire knowledge. But, while approaches suggested by cognitive science supplement Piaget by awakening researchers to the role of auxiliary factors…
Building Safe Concurrency Abstractions
DEFF Research Database (Denmark)
Madsen, Ole Lehrmann
2014-01-01
Concurrent object-oriented programming in Beta is based on semaphores and coroutines and the ability to define high-level concurrency abstractions like monitors, and rendezvous-based communication, and their associated schedulers. The coroutine mechanism of SIMULA has been generalized into the no...
Poster Session- Extended Abstracts
Jack D. Alexander III; Jean Findley; Brenda K. Kury; Jan L. Beyers; Douglas S. Cram; Terrell T. Baker; Jon C. Boren; Carl Edminster; Sue A. Ferguson; Steven McKay; David Nagel; Trent Piepho; Miriam Rorig; Casey Anderson; Jeanne Hoadley; Paulette L. Ford; Mark C. Andersen; Ed L. Fredrickson; Joe Truett; Gary W. Roemer; Brenda K. Kury; Jennifer Vollmer; Christine L. May; Danny C. Lee; James P. Menakis; Robert E. Keane; Zhi-Liang Zhu; Carol Miller; Brett Davis; Katharine Gray; Ken Mix; William P. Kuvlesky Jr.; D. Lynn Drawe; Marcia G. Narog; Roger D. Ottmar; Robert E. Vihnanek; Clinton S. Wright; Timothy E. Paysen; Burton K. Pendleton; Rosemary L. Pendleton; Carleton S. White; John Rogan; Doug Stow; Janet Franklin; Jennifer Miller; Lisa Levien; Chris Fischer; Emma Underwood; Robert Klinger; Peggy Moore; Clinton S. Wright
2008-01-01
Titles found within Poster Session-Extended Abstracts include:Assessment of emergency fire rehabilitation of four fires from the 2000 fire season on the Vale, Oregon, BLM district: review of the density sampling materials and methods: p. 329Â Growth of regreen, seeded for erosion control, in the...
Abstract Introduction Materials & Methods
African Journals Online (AJOL)
plzfg
Abstract. Oral administration to male rats of 200mg kg-1 body weight of an extract of Calendula officinalis flowers every day for 60 days did not cause loss of body weight, but decreased significantly the weight of the testis, epididymis, seminal vesicle and ventral prostate. Sperm motility as well as sperm density were reduced ...
Testing abstract behavioral specifications
P.Y.H. Wong; R. Bubel (Richard); F.S. de Boer (Frank); C.P.T. de Gouw (Stijn); M. Gómez-Zamalloa; R Haehnle; K. Meinke; M.A. Sindhu
2015-01-01
htmlabstractWe present a range of testing techniques for the Abstract Behavioral Specification (ABS) language and apply them to an industrial case study. ABS is a formal modeling language for highly variable, concurrent, component-based systems. The nature of these systems makes them susceptible to
Impredicative concurrent abstract predicates
DEFF Research Database (Denmark)
Svendsen, Kasper; Birkedal, Lars
2014-01-01
We present impredicative concurrent abstract predicates { iCAP { a program logic for modular reasoning about concurrent, higher- order, reentrant, imperative code. Building on earlier work, iCAP uses protocols to reason about shared mutable state. A key novel feature of iCAP is the ability to dene...
Wilson, Cynthia, Ed.; Milliron, Mark David, Ed.
2002-01-01
This 2002 volume of Leadership Abstracts contains issue numbers 1-12. Articles include: (1) "Skills Certification and Workforce Development: Partnering with Industry and Ourselves," by Jeffrey A. Cantor; (2) "Starting Again: The Brookhaven Success College," by Alice W. Villadsen; (3) "From Digital Divide to Digital Democracy," by Gerardo E. de los…
Circularity and Lambda Abstraction
DEFF Research Database (Denmark)
Danvy, Olivier; Thiemann, Peter; Zerny, Ian
2013-01-01
unknowns from what is done to them, which we lambda-abstract with functions. The circular unknowns then become dead variables, which we eliminate. The result is a strict circu- lar program a la Pettorossi. This transformation is reversible: given a strict circular program a la Pettorossi, we introduce...
EBS Radionuclide Transport Abstraction
International Nuclear Information System (INIS)
Schreiner, R.
2001-01-01
The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M and O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other
Abstractions for Mechanical Systems
DEFF Research Database (Denmark)
Sloth, Christoffer; Wisniewski, Rafael
2012-01-01
This paper proposes a method for discretizing the state space of mechanical systems. This is a first attempt in using reduction techniques for mechanical systems in the partitioning of the state space. The method relies on a combination of transversal and tangential manifolds for the conservative...... mechanical system. The tangential manifolds are generated using constants of motion, which can be derived from Noether's theorem. The transversal manifolds are subsequently generated on a reduced space, given by the Routhian, via action-angle coordinates. The method fully applies for integrable systems. We...
Hilbert Space Inner Products for PJ-symmetric Su-Schrieffer-Heeger Models
Czech Academy of Sciences Publication Activity Database
Růžička, František
2015-01-01
Roč. 54, č. 11 (2015), s. 4154-4163 ISSN 0020-7748 Institutional support: RVO:61389005 Keywords : Su-Schrieffer-Heeger model * physical inner products * complete set of pseudometrics * exceptional points Subject RIV: BE - Theoretical Physics Impact factor: 1.041, year: 2015
Lazar, Aurel A; Slutskiy, Yevgeniy B
2015-02-01
We present a multi-input multi-output neural circuit architecture for nonlinear processing and encoding of stimuli in the spike domain. In this architecture a bank of dendritic stimulus processors implements nonlinear transformations of multiple temporal or spatio-temporal signals such as spike trains or auditory and visual stimuli in the analog domain. Dendritic stimulus processors may act on both individual stimuli and on groups of stimuli, thereby executing complex computations that arise as a result of interactions between concurrently received signals. The results of the analog-domain computations are then encoded into a multi-dimensional spike train by a population of spiking neurons modeled as nonlinear dynamical systems. We investigate general conditions under which such circuits faithfully represent stimuli and demonstrate algorithms for (i) stimulus recovery, or decoding, and (ii) identification of dendritic stimulus processors from the observed spikes. Taken together, our results demonstrate a fundamental duality between the identification of the dendritic stimulus processor of a single neuron and the decoding of stimuli encoded by a population of neurons with a bank of dendritic stimulus processors. This duality result enabled us to derive lower bounds on the number of experiments to be performed and the total number of spikes that need to be recorded for identifying a neural circuit.
Jorgensen, Palle E. T.; Pearse, Erin P. J.
2017-06-01
In a previous paper, the authors introduced the idea of a symmetric pair of operators as a way to compute self-adjoint extensions of symmetric operators. In brief, a symmetric pair consists of two densely defined linear operators A and B, with A \\subseteq B^{\\star } and B \\subseteq A^{\\star }. In this paper, we will show by example that symmetric pairs may be used to deduce closability of operators and sometimes even compute adjoints. In particular, we prove that the Malliavin derivative and Skorokhod integral of stochastic calculus are closable, and the closures are mutually adjoint. We also prove that the basic involutions of Tomita-Takesaki theory are closable and that their closures are mutually adjoint. Applications to functions of finite energy on infinite graphs are also discussed, wherein the Laplace operator and inclusion operator form a symmetric pair.
Moment problems in Hilbert space with applications to magnetic resonance imaging
International Nuclear Information System (INIS)
Zwaan, Marcel.
1991-01-01
This thesis is concerned with the mathematical and computational aspects of reconstruction techniques by means of magnetic resonance imaging, in particular for the time-dependent case, referred to as dynamic MRI. The main subjects are: a mathematical framework for dynamic MRI reconstruction; analytic solutions, numerical algorithms and development of reconstruction techniques; stability analysis of the reconstruction algorithms; comparison between these algorithms. (author). 63 refs.; 38 figs.; 5 tabs
Macroscopicity of quantum superpositions on a one-parameter unitary path in Hilbert space
Volkoff, T. J.; Whaley, K. B.
2014-12-01
We analyze quantum states formed as superpositions of an initial pure product state and its image under local unitary evolution, using two measurement-based measures of superposition size: one based on the optimal quantum binary distinguishability of the branches of the superposition and another based on the ratio of the maximal quantum Fisher information of the superposition to that of its branches, i.e., the relative metrological usefulness of the superposition. A general formula for the effective sizes of these states according to the branch-distinguishability measure is obtained and applied to superposition states of N quantum harmonic oscillators composed of Gaussian branches. Considering optimal distinguishability of pure states on a time-evolution path leads naturally to a notion of distinguishability time that generalizes the well-known orthogonalization times of Mandelstam and Tamm and Margolus and Levitin. We further show that the distinguishability time provides a compact operational expression for the superposition size measure based on the relative quantum Fisher information. By restricting the maximization procedure in the definition of this measure to an appropriate algebra of observables, we show that the superposition size of, e.g., NOON states and hierarchical cat states, can scale linearly with the number of elementary particles comprising the superposition state, implying precision scaling inversely with the total number of photons when these states are employed as probes in quantum parameter estimation of a 1-local Hamiltonian in this algebra.
Semilinear stochastic equations in a Hilbert space with a fractional Brownian motion
Czech Academy of Sciences Publication Activity Database
Duncan, T. E.; Maslowski, Bohdan; Pasik-Duncan, B.
2009-01-01
Roč. 40, č. 6 (2009), s. 2286-2315 ISSN 0036-1410 R&D Projects: GA ČR GA201/07/0237 Institutional research plan: CEZ:AV0Z10190503 Keywords : semilinear stochastic equations * fractional Brownian motion * stochastic partial differential equations * absolute continuity of measures Subject RIV: BA - General Mathematics Impact factor: 1.649, year: 2009
International Nuclear Information System (INIS)
Reznik, Benni; Groisman, Berry; Aharonov, Yakir
2002-01-01
We present a systematic simple method for constructing deterministic remote operations on single and multiple systems of arbitrary discrete dimensionality. These operations include remote rotations, remote interactions, and measurements. The resources needed for an operation on a two-level system are one ebit and a bidirectional communication of two cbits, and for an n-level system, a pair of entangled n-level particles and two classical 'nits'. In the latter case, there are n-1 possible distinct operations per n-level entangled pair. Similar results apply for generating interaction between a pair of remote systems, while for remote measurements only one-directional classical communication is needed. We further consider remote operations on N spatially distributed systems, and show that the number of possible distinct operations increases here exponentially, with the available number of entangled pairs that are initially distributed between the systems. Our results follow from the properties of a hybrid state-operator object (stator), which describes quantum correlations between states and operations
Applications of automata and graphs: Labeling operators in Hilbert space. II
International Nuclear Information System (INIS)
Cho, Ilwoo; Jorgensen, Palle E. T.
2009-01-01
We introduced a family of infinite graphs directly associated with a class of von Neumann automaton model A G . These are finite state models used in symbolic dynamics: stimuli models and in control theory. In the context of groupoid von Neumann algebras, and an associated fractal group, we prove a classification theorem for representations of automata.
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.
Hilbert Space Inner Products for PT-symmetric Su-Schrieffer-Heeger Models
Czech Academy of Sciences Publication Activity Database
Růžička, František
2015-01-01
Roč. 54, X (2015), s. 4154-4163 ISSN 0020-7748 Institutional support: RVO:61389005 Keywords : Su-Schrieffer-Heeger model * physical inner products * complete set of pseudometrics Subject RIV: BE - Theoretical Physics Impact factor: 1.041, year: 2015
Dracup, J. A.; Leonardson, R.
2004-12-01
The Pacific Decadal Oscillation (PDO) Index and streamflow in the United States are studied to find temporal patterns on a range of scales. The Hilbert-EMD technique is used on monthly PDO data and on reconstructed uninhibited daily flow data. Hilbert-EMD analysis uses Empirical Mode Decomposition (EMD) to separate the data into sub-signals of various frequency ranges (such as weekly, inter-annual, and decadal), and a residue displaying a long-term trend. The modes are then analyzed using the Hilbert Transform, to determine power and time characteristics of the frequency sub-signals. Hilbert-EMD analysis has been used to study a wide variety of signals from within the geophysical record, including climate variability, earthquakes, and ocean waves. This project displays the temporal patterns of the PDO Index and streamflow at varying scales, and allows correlation analysis of individual frequency modes between the PDO and a number of major US rivers.
Kumar, Keshav; Shukla, Sumitra; Singh, Sachin Kumar
2018-04-01
Periodic impulses arise due to localised defects in rolling element bearing. At the early stage of defects, the weak impulses are immersed in strong machinery vibration. This paper proposes a combined approach based upon Hilbert envelop and zero frequency resonator for the detection of the weak periodic impulses. In the first step, the strength of impulses is increased by taking normalised Hilbert envelop of the signal. It also helps in better localization of these impulses on time axis. In the second step, Hilbert envelope of the signal is passed through the zero frequency resonator for the exact localization of the periodic impulses. Spectrum of the resonator output gives peak at the fault frequency. Simulated noisy signal with periodic impulses is used to explain the working of the algorithm. The proposed technique is verified with experimental data also. A comparison of the proposed method with Hilbert-Haung transform (HHT) based method is presented to establish the effectiveness of the proposed method.
T{sub ρ}{sup σ}(G) theories and their Hilbert series
Energy Technology Data Exchange (ETDEWEB)
Cremonesi, Stefano [Department of Mathematics, King’s College London,The Strand, London WC2R 2LS (United Kingdom); Theoretical Physics Group, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom); Hanany, Amihay [Theoretical Physics Group, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom); Mekareeya, Noppadol [Theory Division, Physics Department, CERN,CH-1211, Geneva 23 (Switzerland); Zaffaroni, Alberto [Dipartimento di Fisica, Università di Milano-Bicocca,I-20126 Milano (Italy); INFN, sezione di Milano-Bicocca,I-20126 Milano (Italy)
2015-01-29
We give an explicit formula for the Higgs and Coulomb branch Hilbert series for the class of 3dN=4 superconformal gauge theories T{sub ρ}{sup σ}(G) corresponding to a set of D3 branes ending on NS5 and D5-branes, with or without O3 planes. Here G is a classical group, σ is a partition of G and ρ a partition of the dual group G{sup ∨}. In deriving such a formula we make use of the recently discovered formula for the Hilbert series of the quantum Coulomb branch of N=4 superconformal theories. The result can be expressed in terms of a generalization of a class of symmetric functions, the Hall-Littlewood polynomials, and can be interpreted in mathematical language in terms of localization. We mainly consider the case G=SU(N) but some interesting results are also given for orthogonal and symplectic groups.
Identifying flight modes of Aerial Planting Projectile using Hilbert-Huang transformation
Goodarzi, H.; Sabzehparvar, M.
2017-11-01
A novel method based on Hilbert Huang Transform (HHT) for analyzing the non-linear and non-stationary of Aerial Planting Projectile (APP) flight data signal is presented. Also an image processing method is used for acquire attitude signals of projectile. Experimental test setup includes an electrical fan, high speed digital camera and projectile that the images of projectile falling down against of fan flow is captured. The frequency components of the projectile attitude signal along separation phase and free falling are complicated. Empirical Mode Decomposition (EMD) can decompose the signal into Intrinsic Mode Functions (IMFs). After a Hilbert transform, the instantaneous frequency and damping ratio of each IMF is obtained to get the physical meaning of each IMF. Analysis results indicate that the flight modes of APP are identified with high accuracy.
Directory of Open Access Journals (Sweden)
Imaouchen Yacine
2015-01-01
Full Text Available To detect rolling element bearing defects, many researches have been focused on Motor Current Signal Analysis (MCSA using spectral analysis and wavelet transform. This paper presents a new approach for rolling element bearings diagnosis without slip estimation, based on the wavelet packet decomposition (WPD and the Hilbert transform. Specifically, the Hilbert transform first extracts the envelope of the motor current signal, which contains bearings fault-related frequency information. Subsequently, the envelope signal is adaptively decomposed into a number of frequency bands by the WPD algorithm. Two criteria based on the energy and correlation analyses have been investigated to automate the frequency band selection. Experimental studies have confirmed that the proposed approach is effective in diagnosing rolling element bearing faults for improved induction motor condition monitoring and damage assessment.
Wei, W.; Schmitt, F. G.; Huang, Y. X.; Zhang, H. S.
2016-05-01
Turbulent characteristics in the atmospheric surface layer are investigated using a data-driven method, Hilbert spectral analysis. The results from empirical mode decomposition display a set of intrinsic mode functions whose characteristic scales suggest a dyadic filter-bank property. It can be concluded from the joint probability density function of the intrinsic mode functions that the turbulent properties are totally different under different stratifications: the amplitudes (or energies) are arranged according to the stability parameter [InlineEquation not available: see fulltext.] for stable conditions, but tend to cluster randomly for unstable cases. The intermittency analyses reveal that second-order Hilbert marginal spectra display a power-law behaviour in the inertial subrange, and that the scaling exponent functions deviate from the theoretical values due to the strong intermittency in the stable boundary layer.
Directory of Open Access Journals (Sweden)
Isti Qomah
2017-01-01
Full Text Available Kerusakan batang rotor merupakan salah satu jenis kerusakan pada motor induksi yang dapat menyebabkan masalah serius. Kerusakan tersebut dapat mencapai 5% - 10% dari seluruh kasus gangguan motor induksi. Oleh karena itu, perlu adanya diagnosis awal yang mendeteksi adanya gangguan pada rotor motor induksi, agar dapat dilakukan perbaikan lebih cepat dan tanggap sebelum terjadi gangguan yang lebih besar. Tugas Akhir ini membahas terkait teknik deteksi kerusakan batang rotor pada motor induksi dengan menggunakan analisis arus mula. Sistem yang digunakan berbasis decomposition wavelet transform terlebih dahulu kemudian dilanjutkan dengan analisis berbasis hilbert transform sebagai perangkat pengolahan sinyal sehingga mampu mendeteksi motor dalam keadaan sehat atau mengalami kerusakan. Pengujian sistem dilakukan dalam beberapa kondisi, yaitu kondisi tanpa beban dan berbeban. Selain itu, kondisi yang diberikan adalah kecacatan mulai dai 1BRB hingga 3BRB. Hasil pengujian membuktikan bahwa decomposition wavelet transform dan Hilbert transform mampu mendeteksi perbedaan kondisi pada motor induksi normal ataupun rusak pada batang rotor.
Zhou, Xing; Lei, Ming; Dan, Dan; Yao, Baoli; Qian, Jia; Yan, Shaohui; Yang, Yanlong; Min, Junwei; Peng, Tong; Ye, Tong; Chen, Guangde
2015-01-01
Structured illumination microscopy (SIM) with axially optical sectioning capability has found widespread applications in three-dimensional live cell imaging in recent years, since it combines high sensitivity, short image acquisition time, and high spatial resolution. To obtain one sectioned slice, three raw images with a fixed phase-shift, normally 2π/3, are generally required. In this paper, we report a data processing algorithm based on the one-dimensional Hilbert transform, which needs only two raw images with arbitrary phase-shift for each single slice. The proposed algorithm is different from the previous two-dimensional Hilbert spiral transform algorithm in theory. The presented algorithm has the advantages of simpler data processing procedure, faster computation speed and better reconstructed image quality. The validity of the scheme is verified by imaging biological samples in our developed DMD-based LED-illumination SIM system. PMID:25799234
Energy Technology Data Exchange (ETDEWEB)
NONE
2017-06-15
The volume includes abstracts of the Annual DEGRO Meeting 2017 covering lectures and poster sessions with the following issues: lymphoma, biology, physics, radioimmunotherapy, sarcomas and rare tumors, prostate carcinoma, lung tumors, benign lesions and new media, mamma carcinoma, gastrointestinal tumors, quality of life, care science and quality assurance, high-technology methods and palliative situation, head-and-neck tumors, brain tumors, central nervous system metastases, guidelines, radiation sensitivity, radiotherapy, radioimmunotherapy.
The deleuzian abstract machines
DEFF Research Database (Denmark)
Werner Petersen, Erik
2005-01-01
in emphasis from the three syntheses to mappings and rhizomatic diagrams that cut across semiotics or “blow apart regimes of signs”. The aim here is the absolute deterritorialization. Deleuze has shown how abstract machines operate in the philosophy of Foucault, the literature of Proust and Kafka......, and the painting of Bacon. We will finish our presentation by showing how these machines apply to architecture....
Energy Technology Data Exchange (ETDEWEB)
NONE
2014-05-15
The proceedings of the SPR 2014 meeting include abstracts on the following topics: Body imaging techniques: practical advice for clinic work; thoracic imaging: focus on the lungs; gastrointestinal imaging: focus on the pancreas and bowel; genitourinary imaging: focus on gonadal radiology; muscoskeletal imaging; focus on oncology; child abuse and nor child abuse: focus on radiography; impact of NMR and CT imaging on management of CHD; education and communication: art and practice in pediatric radiology.
International Nuclear Information System (INIS)
2014-01-01
The proceedings of the SPR 2014 meeting include abstracts on the following topics: Body imaging techniques: practical advice for clinic work; thoracic imaging: focus on the lungs; gastrointestinal imaging: focus on the pancreas and bowel; genitourinary imaging: focus on gonadal radiology; muscoskeletal imaging; focus on oncology; child abuse and nor child abuse: focus on radiography; impact of NMR and CT imaging on management of CHD; education and communication: art and practice in pediatric radiology.
Bazargani, Hamed Pishvai; Burla, Maurizio; Chrostowski, Lukas; Azaña, José
2016-11-01
We experimentally demonstrate high-performance integer and fractional-order photonic Hilbert transformers based on laterally apodized Bragg gratings in a silicon-on-insulator technology platform. The sub-millimeter-long gratings have been fabricated using single-etch electron beam lithography, and the resulting HT devices offer operation bandwidths approaching the THz range, with time-bandwidth products between 10 and 20.
Hilbert-Huang transform for analysis of heart rate variability in cardiac health.
Li, Helong; Kwong, Sam; Yang, Lihua; Huang, Daren; Xiao, Dongping
2011-01-01
This paper introduces a modified technique based on Hilbert-Huang transform (HHT) to improve the spectrum estimates of heart rate variability (HRV). In order to make the beat-to-beat (RR) interval be a function of time and produce an evenly sampled time series, we first adopt a preprocessing method to interpolate and resample the original RR interval. Then, the HHT, which is based on the empirical mode decomposition (EMD) approach to decompose the HRV signal into several monocomponent signals that become analytic signals by means of Hilbert transform, is proposed to extract the features of preprocessed time series and to characterize the dynamic behaviors of parasympathetic and sympathetic nervous system of heart. At last, the frequency behaviors of the Hilbert spectrum and Hilbert marginal spectrum (HMS) are studied to estimate the spectral traits of HRV signals. In this paper, two kinds of experiment data are used to compare our method with the conventional power spectral density (PSD) estimation. The analysis results of the simulated HRV series show that interpolation and resampling are basic requirements for HRV data processing, and HMS is superior to PSD estimation. On the other hand, in order to further prove the superiority of our approach, real HRV signals are collected from seven young health subjects under the condition that autonomic nervous system (ANS) is blocked by certain acute selective blocking drugs: atropine and metoprolol. The high-frequency power/total power ratio and low-frequency power/high-frequency power ratio indicate that compared with the Fourier spectrum based on principal dynamic mode, our method is more sensitive and effective to identify the low-frequency and high-frequency bands of HRV.
Patient Specific Seizure Prediction System Using Hilbert Spectrum and Bayesian Networks Classifiers
Ozdemir, Nilufer; Yildirim, Esen
2014-01-01
The aim of this paper is to develop an automated system for epileptic seizure prediction from intracranial EEG signals based on Hilbert-Huang transform (HHT) and Bayesian classifiers. Proposed system includes decomposition of the signals into intrinsic mode functions for obtaining features and use of Bayesian networks with correlation based feature selection for binary classification of preictal and interictal recordings. The system was trained and tested on Freiburg EEG database. 58 hours of...
Polynomial approximation of functions in Sobolev spaces
International Nuclear Information System (INIS)
Dupont, T.; Scott, R.
1980-01-01
Constructive proofs and several generalizations of approximation results of J. H. Bramble and S. R. Hilbert are presented. Using an averaged Taylor series, we represent a function as a polynomical plus a remainder. The remainder can be manipulated in many ways to give different types of bounds. Approximation of functions in fractional order Sobolev spaces is treated as well as the usual integer order spaces and several nonstandard Sobolev-like spaces
EBS Radionuclide Transport Abstraction
International Nuclear Information System (INIS)
J. Prouty
2006-01-01
The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport
EBS Radionuclide Transport Abstraction
Energy Technology Data Exchange (ETDEWEB)
J. Prouty
2006-07-14
The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport
Treatment of electrochemical noise data by the Hilbert-Huang transform
International Nuclear Information System (INIS)
Rahier, A.
2009-01-01
Most of the classical approaches for treating electro-chemical noise (ECN) data suffer from the non-linear and non steady-state character of the delivered signal. Very often, the link between time and the local corrosion events supposedly responsible for ECN data signatures is lost during treatment, as is obvious when using the classical Fourier Transform (FT), followed by an analysis of the response in the frequency domain. In this particular case, the information directly related to the corrosion events is distributed into the full spectra, thereby preventing the operator to derive clear and precise conclusions. In 2005, we suggested an alternative data treatment based on the Hilbert-Huang transform (HHT). The latter keeps track of the time variable and copes with non-linear and non steady-state behaviours of the system under examination. In 2006, we demonstrated the applicability of the newly proposed data treatment in the case of ECN data collected under BWR (Boiling Water Reactor) conditions. In 2007, we collected additional ECN data and started a preliminary investigation of two mathematical restrictions that are susceptible to impair the interpretation of the results. We discovered a possible modification of the Hilbert transform allowing generating controlled phase shifts that are different from pi/2 as is always the case for the Hilbert transform
Wang, Chenxing; Da, Feipeng
2012-06-01
To address the issue of the intermittent noise in optical fringe pattern, an adaptive method of noise reduction is given based on empirical mode decomposition (EMD) and Hilbert Huang transform (HHT), and then the wrapped phase is obtained by performing the Hilbert transform on the refined pattern. Firstly, the signal of the fringe pattern is decomposed into several intrinsic mode functions (IMFs). With the instantaneous frequencies and marginal spectra of each IMF obtained by HHT, the criterion of identifying the noise IMF is determined. Then, it is judged whether a mode-mixing problem, which is the frequent problem in traditional EMD, appears in each noise IMF. If the problem appears, the ``noise,'' which is designed according to the signal adaptively, is added to the original signal, and then the obtained new signal is decomposed again. The process will be repeated until there is no mode mixing in the noise IMF. Finally, the wrapped phase is obtained by performing a Hilbert transform on the refined pattern with noise and background components removed. The proposed method can solve the mode-mixing problem effectively. It can reduce most of the noise and maintain a large amount of detailed phase information simultaneously. Simulation and compared experiments show the efficiency, robustness, and accuracy of the proposed method.
Water stage component analysis in an estuary using the Hilbert Huang transform
Directory of Open Access Journals (Sweden)
Yen-Chang Chen
2018-01-01
Full Text Available This study applies a novel concept to decompose water stages to understand the factors that affect an estuary. The estuary water stages vary due to different complex, often nonlinear and non-stationary factors. Therefore, it is very difficult for researchers to break down water stages into contributing factors with single integrated methods. The Hilbert Huang transform (HHT is an easy to use, efficient and powerful method of processing non-stationary, non-linear signals to optimize a complicated data process. The HHT is composed of empirical mode decomposition (EMD and Hilbert transform. EMD decomposes the water stages into several intrinsic mode functions (IMFs. Through the Hilbert transform, IMFs could obtain amplitude and instantaneous frequency with time. Those IMFs with amplitude and frequency can be used to represent those factors that affect the water stages in an estuary. However, the physical meanings represented by IMFs should be inferred in conjunction with the other hydrological data. This study uses Tanshui River estuary water stages to show HHT applied to determining the factors that affect the water stages. HHT application provides a methodology for others to follow to identify the water stage components in an estuary.
Geometric approach to evolution problems in metric spaces
Stojković, Igor
2011-01-01
This PhD thesis contains four chapters where research material is presented. In the second chapter the extension of the product formulas for semigroups induced by convex functionals, from the classical Hilbert space setting to the setting of general CAT(0) spaces. In the third chapter, the
Analysis of complex networks using aggressive abstraction.
Energy Technology Data Exchange (ETDEWEB)
Colbaugh, Richard; Glass, Kristin.; Willard, Gerald
2008-10-01
This paper presents a new methodology for analyzing complex networks in which the network of interest is first abstracted to a much simpler (but equivalent) representation, the required analysis is performed using the abstraction, and analytic conclusions are then mapped back to the original network and interpreted there. We begin by identifying a broad and important class of complex networks which admit abstractions that are simultaneously dramatically simplifying and property preserving we call these aggressive abstractions -- and which can therefore be analyzed using the proposed approach. We then introduce and develop two forms of aggressive abstraction: 1.) finite state abstraction, in which dynamical networks with uncountable state spaces are modeled using finite state systems, and 2.) onedimensional abstraction, whereby high dimensional network dynamics are captured in a meaningful way using a single scalar variable. In each case, the property preserving nature of the abstraction process is rigorously established and efficient algorithms are presented for computing the abstraction. The considerable potential of the proposed approach to complex networks analysis is illustrated through case studies involving vulnerability analysis of technological networks and predictive analysis for social processes.
International Nuclear Information System (INIS)
1978-01-01
This volume contains the program and abstracts of the conference. The following topics are included: metal vapor molecular lasers, magnetohydrodynamics, rare gas halide and nuclear pumped lasers, transfer mechanisms in arcs, kinetic processes in rare gas halide lasers, arcs and flows, XeF kinetics and lasers, fundamental processes in excimer lasers, electrode effects and vacuum arcs, electron and ion transport, ion interactions and mobilities, glow discharges, diagnostics and afterglows, dissociative recombination, electron ionization and excitation, rare gas excimers and group VI lasers, breakdown, novel laser pumping techniques, electrode-related discharge phenomena, photon interactions, attachment, plasma chemistry and infrared lasers, electron scattering, and reactions of excited species
International Nuclear Information System (INIS)
2015-01-01
The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.
Energy Technology Data Exchange (ETDEWEB)
NONE
2015-05-10
The volume includes the abstracts of the ESPR 2015 covering the following topics: PCG (post graduate courses): Radiography; fluoroscopy and general issue; nuclear medicine, interventional radiology and hybrid imaging, pediatric CT, pediatric ultrasound; MRI in childhood. Scientific sessions and task force sessions: International aspects; neuroradiology, neonatal imaging, engineering techniques to simulate injury in child abuse, CT - dose and quality, challenges in the chest, cardiovascular and chest, muscoskeletal, oncology, pediatric uroradiology and abdominal imaging, fetal and postmortem imaging, education and global challenges, neuroradiology - head and neck, gastrointestinal and genitourinary.
Energy Technology Data Exchange (ETDEWEB)
NONE
2016-05-15
The volume on the meeting of pediatric radiology includes abstract on the following issues: chest, cardiovascular system, neuroradiology, CT radiation DRs (diagnostic reference levels) and dose reporting guidelines, genitourinary imaging, gastrointestinal radiology, oncology an nuclear medicine, whole body imaging, fetal/neonates imaging, child abuse, oncology and hybrid imaging, value added imaging, muscoskeletal imaging, dose and radiation safety, imaging children - immobilization and distraction techniques, information - education - QI and healthcare policy, ALARA, the knowledge skills and competences for a technologist/radiographer in pediatric radiology, full exploitation of new technological features in pediatric CT, image quality issues in pediatrics, abdominal imaging, interventional radiology, MR contrast agents, tumor - mass imaging, cardiothoracic imaging, ultrasonography.
Energy Technology Data Exchange (ETDEWEB)
NONE
2017-05-15
The conference proceedings SPR 2017 include abstracts on the following issues: gastrointestinal radiography - inflammatory bowel diseases, cardiovascular CTA, general muscoskeletal radiology, muscoskeletal congenital development diseases, general pediatric radiology - chest, muscoskeletal imaging - marrow and infectious disorders, state-of-the-art body MR imaging, practical pediatric sonography, quality and professionalism, CT imaging in congenital heart diseases, radiographic courses, body MT techniques, contrast enhanced ultrasound, machine learning, forensic imaging, the radiation dos conundrum - reconciling imaging, imagining and managing, the practice of radiology, interventional radiology, neuroradiology, PET/MR.
DEFF Research Database (Denmark)
Olesen, Henning Salling
2006-01-01
The anniversary of the International Journal of Lifelong Education takes place in the middle of a conceptual landslide from lifelong education to lifelong learning. Contemporary discourses of lifelong learning etc are however abstractions behind which new functions and agendas for adult education...... are set. The ideological discourse of recent policies seems to neglect the fact that history and resources for lifelong learning are different across Europe, and also neglects the multiplicity of adult learners. Instead of refusing the new agendas, however, adult education research should try to dissolve...... learning. Adult education research must fulfil it's potential conversion from normative philosophy to critical and empirical social science....
Parameterized Dataflow (Extended Abstract
Directory of Open Access Journals (Sweden)
Dominic Duggan
2016-10-01
Full Text Available Dataflow networks have application in various forms of stream processing, for example for parallel processing of multimedia data. The description of dataflow graphs, including their firing behavior, is typically non-compositional and not amenable to separate compilation. This article considers a dataflow language with a type and effect system that captures the firing behavior of actors. This system allows definitions to abstract over actor firing rates, supporting the definition and safe composition of actor definitions where firing rates are not instantiated until a dataflow graph is launched.
International Nuclear Information System (INIS)
Wilson, Michael L.
2001-01-01
Drift seepage refers to flow of liquid water into repository emplacement drifts, where it can potentially contribute to degradation of the engineered systems and release and transport of radionuclides within the drifts. Because of these important effects, seepage into emplacement drifts is listed as a ''principal factor for the postclosure safety case'' in the screening criteria for grading of data in Attachment 1 of AP-3.15Q, Rev. 2, ''Managing Technical Product Inputs''. Abstraction refers to distillation of the essential components of a process model into a form suitable for use in total-system performance assessment (TSPA). Thus, the purpose of this analysis/model is to put the information generated by the seepage process modeling in a form appropriate for use in the TSPA for the Site Recommendation. This report also supports the Unsaturated-Zone Flow and Transport Process Model Report. The scope of the work is discussed below. This analysis/model is governed by the ''Technical Work Plan for Unsaturated Zone Flow and Transport Process Model Report'' (CRWMS MandO 2000a). Details of this activity are in Addendum A of the technical work plan. The original Work Direction and Planning Document is included as Attachment 7 of Addendum A. Note that the Work Direction and Planning Document contains tasks identified for both Performance Assessment Operations (PAO) and Natural Environment Program Operations (NEPO). Only the PAO tasks are documented here. The planning for the NEPO activities is now in Addendum D of the same technical work plan and the work is documented in a separate report (CRWMS MandO 2000b). The Project has been reorganized since the document was written. The responsible organizations in the new structure are the Performance Assessment Department and the Unsaturated Zone Department, respectively. The work plan for the seepage abstraction calls for determining an appropriate abstraction methodology, determining uncertainties in seepage, and providing
Multiresolution Hilbert Approach to Multidimensional Gauss-Markov Processes
Directory of Open Access Journals (Sweden)
Thibaud Taillefumier
2011-01-01
Full Text Available The study of the multidimensional stochastic processes involves complex computations in intricate functional spaces. In particular, the diffusion processes, which include the practically important Gauss-Markov processes, are ordinarily defined through the theory of stochastic integration. Here, inspired by the Lévy-Ciesielski construction of the Wiener process, we propose an alternative representation of multidimensional Gauss-Markov processes as expansions on well-chosen Schauder bases, with independent random coefficients of normal law with zero mean and unit variance. We thereby offer a natural multiresolution description of the Gauss-Markov processes as limits of finite-dimensional partial sums of the expansion, that are strongly almost-surely convergent. Moreover, such finite-dimensional random processes constitute an optimal approximation of the process, in the sense of minimizing the associated Dirichlet energy under interpolating constraints. This approach allows for a simpler treatment of problems in many applied and theoretical fields, and we provide a short overview of applications we are currently developing.
Engineering Abstractions in Model Checking and Testing
DEFF Research Database (Denmark)
Achenbach, Michael; Ostermann, Klaus
2009-01-01
Abstractions are used in model checking to tackle problems like state space explosion or modeling of IO. The application of these abstractions in real software development processes, however, lacks engineering support. This is one reason why model checking is not widely used in practice yet...... and testing is still state of the art in falsification. We show how user-defined abstractions can be integrated into a Java PathFinder setting with tools like AspectJ or Javassist and discuss implications of remaining weaknesses of these tools. We believe that a principled engineering approach to designing...
EBS Radionuclide Transport Abstraction
Energy Technology Data Exchange (ETDEWEB)
J.D. Schreiber
2005-08-25
The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport
EBS Radionuclide Transport Abstraction
International Nuclear Information System (INIS)
J.D. Schreiber
2005-01-01
The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers
Reconstruction of abstract quantum theory
International Nuclear Information System (INIS)
Drieschner, M.; Goernitz, T.; von Weizsaecker, C.F.
1988-01-01
Understanding quantum theory as a general theory of prediction, we reconstruct abstract quantum theory. Abstract means the general frame of quantum theory, without reference to a three-dimensional position space, to concepts like particle or field, or to special laws of dynamics. Reconstruction is the attempt to do this by formulating simple and plausible postulates on prediction in order to derive the basic concepts of quantum theory from them. Thereby no law of classical physics is presupposed which would then have to be quantized. We briefly discuss the relationship of theory and interpretation in physics and the fundamental role of time as a basic concept for physics. Then a number of assertions are given, formulated as succinctly as possible in order to make them easily quotable and comparable. The assertations are arranged in four groups: heuristic principles, verbal definitions of some terms, three basic postulates, and consequences. The three postulates of separable alternatives, indeterminism, and kinematics are the central points of this work. These brief assertions are commented upon, and their relationship with the interpretation of quantum theory is discussed. Also given are an outlook on the further development into concrete quantum theory and some philosophical reflections
1981-12-01
with irreversible pulpitis were: presence of sclerosis and/or enlargement of periodontal ligament space; pain duration greater than one hour and...treatment materials and methods were recorded. Pulpitis criteria were used to determine success/failure of treatment at yearly recall intervals. Success...direct pulp cap, all with permanent restorations. The establishment of criteria for determining irreversible pulp disease in teeth with deep carious
Wadsworth, A R
2017-01-01
This is a book of problems in abstract algebra for strong undergraduates or beginning graduate students. It can be used as a supplement to a course or for self-study. The book provides more variety and more challenging problems than are found in most algebra textbooks. It is intended for students wanting to enrich their learning of mathematics by tackling problems that take some thought and effort to solve. The book contains problems on groups (including the Sylow Theorems, solvable groups, presentation of groups by generators and relations, and structure and duality for finite abelian groups); rings (including basic ideal theory and factorization in integral domains and Gauss's Theorem); linear algebra (emphasizing linear transformations, including canonical forms); and fields (including Galois theory). Hints to many problems are also included.
International Nuclear Information System (INIS)
Sahin, S.
2007-01-01
In this book Conference Program and Abstracts were included 13th International Conference on Emerging Nuclear Energy Systems which held between 03-08 June 2007 in Istanbul, Turkey. The main objective of International Conference series on Emerging Nuclear Energy Systems (ICENES) is to provide an international scientific and technical forum for scientists, engineers, industry leaders, policy makers, decision makers and young professionals who will shape future energy supply and technology , for a broad review and discussion of various advanced, innovative and non-conventional nuclear energy production systems. The main topics of 159 accepted papers from 35 countries are fusion science and technology, fission reactors, accelerator driven systems, transmutation, laser in nuclear technology, radiation shielding, nuclear reactions, hydrogen energy, solar energy, low energy physics and societal issues
In-Package Chemistry Abstraction
Energy Technology Data Exchange (ETDEWEB)
P.S. Domski
2003-07-21
The work associated with the development of this model report was performed in accordance with the requirements established in ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of SR and LA'' (BSC 2002a). The in-package chemistry model and in-package chemistry model abstraction are developed to predict the bulk chemistry inside of a failed waste package and to provide simplified expressions of that chemistry. The purpose of this work is to provide the abstraction model to the Performance Assessment Project and the Waste Form Department for development of geochemical models of the waste package interior. The scope of this model report is to describe the development and validation of the in-package chemistry model and in-package chemistry model abstraction. The in-package chemistry model will consider chemical interactions of water with the waste package materials and the waste form for commercial spent nuclear fuel (CSNF) and codisposed high-level waste glass (HLWG) and N Reactor spent fuel (CDNR). The in-package chemistry model includes two sub-models, the first a water vapor condensation (WVC) model, where water enters a waste package as vapor and forms a film on the waste package components with subsequent film reactions with the waste package materials and waste form--this is a no-flow model, the reacted fluids do not exit the waste package via advection. The second sub-model of the in-package chemistry model is the seepage dripping model (SDM), where water, water that may have seeped into the repository from the surrounding rock, enters a failed waste package and reacts with the waste package components and waste form, and then exits the waste package with no accumulation of reacted water in the waste package. Both of the submodels of the in-package chemistry model are film models in contrast to past in-package chemistry models where all of the waste package pore space was filled with water. The
An abstract approach to music.
Energy Technology Data Exchange (ETDEWEB)
Kaper, H. G.; Tipei, S.
1999-04-19
In this article we have outlined a formal framework for an abstract approach to music and music composition. The model is formulated in terms of objects that have attributes, obey relationships, and are subject to certain well-defined operations. The motivation for this approach uses traditional terms and concepts of music theory, but the approach itself is formal and uses the language of mathematics. The universal object is an audio wave; partials, sounds, and compositions are special objects, which are placed in a hierarchical order based on time scales. The objects have both static and dynamic attributes. When we realize a composition, we assign values to each of its attributes: a (scalar) value to a static attribute, an envelope and a size to a dynamic attribute. A composition is then a trajectory in the space of aural events, and the complex audio wave is its formal representation. Sounds are fibers in the space of aural events, from which the composer weaves the trajectory of a composition. Each sound object in turn is made up of partials, which are the elementary building blocks of any music composition. The partials evolve on the fastest time scale in the hierarchy of partials, sounds, and compositions. The ideas outlined in this article are being implemented in a digital instrument for additive sound synthesis and in software for music composition. A demonstration of some preliminary results has been submitted by the authors for presentation at the conference.
International Nuclear Information System (INIS)
Hein, Torsten
2008-01-01
In this paper we deal with convergence rates for regularizing ill-posed problems with operator mapping from a Hilbert space into a Banach space. Since we cannot transfer the well-established convergence rates theory in Hilbert spaces, only few convergence rates results are known in the literature for this situation. Therefore we present an alternative approach for deriving convergence rates. Hereby we deal with so-called distance functions which quantify the violation of a reference source condition. With the aid of these functions we present error bounds and convergence rates for regularized solutions of linear and nonlinear problems when the reference source condition is not satisfied. We show that the approach of applying distance functions carries over the idea of considering generalized source conditions in Hilbert spaces to inverse problems in Banach spaces in a natural way. Introducing this topic for linear ill-posed problems we additionally show that this theory can be easily extended to nonlinear problems
Notes on qubit phase space and discrete symplectic structures
International Nuclear Information System (INIS)
Livine, Etera R
2010-01-01
We start from Wootter's construction of discrete phase spaces and Wigner functions for qubits and more generally for finite-dimensional Hilbert spaces. We look at this framework from a non-commutative space perspective and we focus on the Moyal product and the differential calculus on these discrete phase spaces. In particular, the qubit phase space provides the simplest example of a four-point non-commutative phase space. We give an explicit expression of the Moyal bracket as a differential operator. We then compare the quantum dynamics encoded by the Moyal bracket to the classical dynamics: we show that the classical Poisson bracket does not satisfy the Jacobi identity thus leaving the Moyal bracket as the only consistent symplectic structure. We finally generalize our analysis to Hilbert spaces of prime dimensions d and their associated d x d phase spaces.
Notes on qubit phase space and discrete symplectic structures
Energy Technology Data Exchange (ETDEWEB)
Livine, Etera R, E-mail: etera.livine@ens-lyon.f [Laboratoire de Physique, ENS Lyon, CNRS UMR 5672, 46 Allee d' Italie, 69364 Lyon (France)
2010-02-19
We start from Wootter's construction of discrete phase spaces and Wigner functions for qubits and more generally for finite-dimensional Hilbert spaces. We look at this framework from a non-commutative space perspective and we focus on the Moyal product and the differential calculus on these discrete phase spaces. In particular, the qubit phase space provides the simplest example of a four-point non-commutative phase space. We give an explicit expression of the Moyal bracket as a differential operator. We then compare the quantum dynamics encoded by the Moyal bracket to the classical dynamics: we show that the classical Poisson bracket does not satisfy the Jacobi identity thus leaving the Moyal bracket as the only consistent symplectic structure. We finally generalize our analysis to Hilbert spaces of prime dimensions d and their associated d x d phase spaces.
Neighbourhood Abstraction in GROOVE - Tool Paper
Rensink, Arend; Zambon, Eduardo; de Lara, Juan; Varro, Daniel
In this paper we discuss the implementation of neighbourhood graph abstraction in the GROOVE tool set. Important classes of graph grammars may have unbounded state spaces and therefore cannot be verified with traditional model checking techniques. One way to address this problem is to perform graph
Operator algebra in the space of images
Celeghini, Enrico
2017-08-01
A consistent description of images on the disk and of their transformations is given as elements of a vector space and of an operators algebra. The vector space of images on the disk 𝔻 is the Hilbert space L 2(𝔻) that has as a basis the Zernike functions. To construct the operator algebra that transforms the images, L 2(𝔻) must be complemented and the full rigged Hilbert space RHS(𝔻) considered. Only this rigged Hilbert space allows indeed to write the operators of different cardinality we need to build the ladder operators on the Zernike functions that by inspection, belong to the representation {D}1/2+\\otimes {D}1/2+ of the algebra su(1, 1) ⊕ su(1, 1). Consequently the transformations of images are operators contained inside the universal enveloping algebra UEA[su(1, 1) ⊕ su(1, 1)]. Because of limited precision of experimental measures, physical states can be always described by vectors of the Schwartz space 𝕊(𝔻), dense in the L 2(𝔻) space where the manipulation of images is performed.
Exoplanets and Multiverses (Abstract)
Trimble, V.
2016-12-01
(Abstract only) To the ancients, the Earth was the Universe, of a size to be crossed by a god in a day, by boat or chariot, and by humans in a lifetime. Thus an exoplanet would have been a multiverse. The ideas gradually separated over centuries, with gradual acceptance of a sun-centered solar system, the stars as suns likely to have their own planets, other galaxies beyond the Milky Way, and so forth. And whenever the community divided between "just one' of anything versus "many," the "manies" have won. Discoveries beginning in 1991 and 1995 have gradually led to a battalion or two of planets orbiting other stars, very few like our own little family, and to moderately serious consideration of even larger numbers of other universes, again very few like our own. I'm betting, however, on habitable (though not necessarily inhabited) exoplanets to be found, and habitable (though again not necessarily inhabited) universes. Only the former will yield pretty pictures.
International Nuclear Information System (INIS)
2013-06-01
ANIMMA 2013 is the third of a series of conferences devoted to endorsing and promoting scientific and technical activities based on nuclear instrumentation and measurements. The main objective of ANIMMA conference is to unite the various scientific communities not only involved in nuclear instrumentation and measurements, but also in nuclear medicine and radiation. The conference is all about getting scientists, engineers and the industry to meet, exchange cultures and identify new scientific and technical prospects to help overcome both current and future unresolved issues. The conference provides scientists and engineers with a veritable opportunity to compare their latest research and development in different areas: physics, nuclear energy, nuclear fuel cycle, safety, security, future energies (GEN III+, GENIV, ITER, ...). The conference topics include instrumentation and measurement methods for: Fundamental physics; Fusion diagnostics and technology; Nuclear power reactors; Research reactors; Nuclear fuel cycle; Decommissioning, dismantling and remote handling; Safeguards, homeland security; Severe accident monitoring; Environmental and medical sciences; Education, training and outreach. This document brings together the abstracts of the presentations. Each presentation (full paper) is analysed separately and entered in INIS
International Nuclear Information System (INIS)
Lumsden, M.D.; Argyriou, D.N.; Inosov, D.
2012-01-01
The microscopic origin of unconventional superconductivity continues to attract the attention of the condensed matter community. Whereas rare-earth / actinide-based intermetallic and copper oxide-based high temperature superconductors are studied for more than twenty years, the iron-based superconductors have been in the focus of interest since their recent discovery. Inelastic neutron scattering experiments have been of particular importance for the understanding of the magnetic and superconducting properties of these compounds. With its 29 talks and 14 posters the workshop provided a forum for the 71 registered participants to review and discuss experimental achievements, recognize the observed synergy and differences as well as discuss theoretical efforts to identify the symmetry of the superconducting order parameter in addition to the coupling mechanisms of the Cooper pairs. The workshop covered different topics relevant for the study of unconventional superconductivity. Magnetization and lattice dynamics such as spin resonances, phonons, magnetic and other excitations as studied by spectroscopic methods were presented. Investigations of (doping, pressure and magnetic field dependent) phase diagrams, electronic states as well as vortex physics by the various diffraction techniques were also addressed. This document gathers only the abstracts of the papers. (authors)
Automated Supernova Discovery (Abstract)
Post, R. S.
2015-12-01
(Abstract only) We are developing a system of robotic telescopes for automatic recognition of Supernovas as well as other transient events in collaboration with the Puckett Supernova Search Team. At the SAS2014 meeting, the discovery program, SNARE, was first described. Since then, it has been continuously improved to handle searches under a wide variety of atmospheric conditions. Currently, two telescopes are used to build a reference library while searching for PSN with a partial library. Since data is taken every night without clouds, we must deal with varying atmospheric and high background illumination from the moon. Software is configured to identify a PSN, reshoot for verification with options to change the run plan to acquire photometric or spectrographic data. The telescopes are 24-inch CDK24, with Alta U230 cameras, one in CA and one in NM. Images and run plans are sent between sites so the CA telescope can search while photometry is done in NM. Our goal is to find bright PSNs with magnitude 17.5 or less which is the limit of our planned spectroscopy. We present results from our first automated PSN discoveries and plans for PSN data acquisition.
Stellar Presentations (Abstract)
Young, D.
2015-12-01
(Abstract only) The AAVSO is in the process of expanding its education, outreach and speakers bureau program. powerpoint presentations prepared for specific target audiences such as AAVSO members, educators, students, the general public, and Science Olympiad teams, coaches, event supervisors, and state directors will be available online for members to use. The presentations range from specific and general content relating to stellar evolution and variable stars to specific activities for a workshop environment. A presentation—even with a general topic—that works for high school students will not work for educators, Science Olympiad teams, or the general public. Each audience is unique and requires a different approach. The current environment necessitates presentations that are captivating for a younger generation that is embedded in a highly visual and sound-bite world of social media, twitter and U-Tube, and mobile devices. For educators, presentations and workshops for themselves and their students must support the Next Generation Science Standards (NGSS), the Common Core Content Standards, and the Science Technology, Engineering and Mathematics (STEM) initiative. Current best practices for developing relevant and engaging powerpoint presentations to deliver information to a variety of targeted audiences will be presented along with several examples.
The de Finetti theorem for test spaces
International Nuclear Information System (INIS)
Barrett, Jonathan; Leifer, Matthew
2009-01-01
We prove a de Finetti theorem for exchangeable sequences of states on test spaces, where a test space is a generalization of the sample space of classical probability theory and the Hilbert space of quantum theory. The standard classical and quantum de Finetti theorems are obtained as special cases. By working in a test space framework, the common features that are responsible for the existence of these theorems are elucidated. In addition, the test space framework is general enough to imply a de Finetti theorem for classical processes. We conclude by discussing the ways in which our assumptions may fail, leading to probabilistic models that do not have a de Finetti theorem.
DEFF Research Database (Denmark)
Otto, Lene
2012-01-01
social and age groups are regarded? In what ways has different practices limited or extended its involvement in the body? Has work been organized hierarchically in relation to the degree of direct body work? What happened when body work became mediated by machines and technology? Has body work as forms......This panel will explore the usefulness of the term ‘body work’ in cultural history. Body work is understood as work focusing on the bodies of others as component in a range of occupations in health and social care, as well as in unpaid work in the family. How can the notion of body work inform...... cultural history of health and illness whether through a micro-social focus on the intercorporeal aspects of work in health and social care, or through clarifying our understanding of the times and spaces of work, or through highlighting the relationship between mundane body work and global processes...
DEFF Research Database (Denmark)
Otto, Lene
2012-01-01
This panel will explore the usefulness of the term ‘body work’ in cultural history. Body work is understood as work focusing on the bodies of others as component in a range of occupations in health and social care, as well as in unpaid work in the family. How can the notion of body work inform...... cultural history of health and illness whether through a micro-social focus on the intercorporeal aspects of work in health and social care, or through clarifying our understanding of the times and spaces of work, or through highlighting the relationship between mundane body work and global processes....... The British sociologist Julia Twigg has introduced and explored the term `bodywork', most recently in Body Work in Health and Social Care - Critical Themes, New Agendas (2011). She extends the term body work from applying to the work that individuals undertake on their own bodies, often as part of regimens...
Functional Correspondence between Evaluators and Abstract Machines
DEFF Research Database (Denmark)
Ager, Mads Stig; Biernacki, Dariusz; Danvy, Olivier
2003-01-01
We bridge the gap between functional evaluators and abstract machines for the λ-calculus, using closure conversion, transformation into continuation-passing style, and defunctionalization.We illustrate this approach by deriving Krivine's abstract machine from an ordinary call-by-name evaluator...... and by deriving an ordinary call-by-value evaluator from Felleisen et al.'s CEK machine. The first derivation is strikingly simpler than what can be found in the literature. The second one is new. Together, they show that Krivine's abstract machine and the CEK machine correspond to the call-by-name and call......-by-value facets of an ordinary evaluator for the λ-calculus.We then reveal the denotational content of Hannan and Miller's CLS machine and of Landin's SECD machine. We formally compare the corresponding evaluators and we illustrate some degrees of freedom in the design spaces of evaluators and of abstract...
DEFF Research Database (Denmark)
Vincent, Claire Louise; Giebel, Gregor; Pinson, Pierre
2010-01-01
a 4-yr time series of 10-min wind speed observations. An adaptive spectral analysis method called the Hilbert–Huang transform is chosen for the analysis, because the nonstationarity of time series of wind speed observations means that they are not well described by a global spectral analysis method...... such as the Fourier transform. The Hilbert–Huang transform is a local method based on a nonparametric and empirical decomposition of the data followed by calculation of instantaneous amplitudes and frequencies using the Hilbert transform. The Hilbert–Huang transformed 4-yr time series is averaged and summarized...
A New View of Earthquake Ground Motion Data: The Hilbert Spectral Analysis
Huang, Norden; Busalacchi, Antonio J. (Technical Monitor)
2000-01-01
A brief description of the newly developed Empirical Mode Decomposition (ENID) and Hilbert Spectral Analysis (HSA) method will be given. The decomposition is adaptive and can be applied to both nonlinear and nonstationary data. Example of the method applied to a sample earthquake record will be given. The results indicate those low frequency components, totally missed by the Fourier analysis, are clearly identified by the new method. Comparisons with Wavelet and window Fourier analysis show the new method offers much better temporal and frequency resolutions.
DEFF Research Database (Denmark)
Truelsen, Jimi Lee
2011-01-01
W. Luo and P. Sarnak have proved the quantum unique ergodicity property for Eisenstein series on PSL(2, )\\. Their result is quantitative in the sense that they find the precise asymptotics of the measure considered. We extend their result to Eisenstein series on , where is the ring of integers...... in a totally real field of degree n over with narrow class number one, using the Eisenstein series considered by I. Efrat. We also give an expository treatment of the theory of Hecke operators on non-holomorphic Hilbert modular forms....
Vogt, Dominik Walter; Leonhardt, Rainer
2017-07-10
We report on data processing for continuous wave (CW) terahertz (THz) spectroscopy measurements based on a Hilbert spectral analysis to achieve MHz resolution. As an example we investigate the spectral properties of a whispering gallery mode (WGM) THz bubble resonator at critical coupling. The experimental verification clearly demonstrates the significant advantages in relative frequency resolution and required acquisition time of the proposed method over the traditional data analysis. An effective frequency resolution, only limited by the precision and stability of the laser beat signal, can be achieved without complex extensions to a standard commercially available CW THz spectrometer.
Quantum mechanics in phase space
DEFF Research Database (Denmark)
Hansen, Frank
1984-01-01
A reformulation of quantum mechanics for a finite system is given using twisted multiplication of functions on phase space and Tomita's theory of generalized Hilbert algebras. Quantization of a classical observable h is achieved when the twisted exponential Exp0(-h) is defined as a tempered....... Generalized Weyl-Wigner maps related to the notion of Hamiltonian weight are studied and used in the formulation of a twisted spectral theory for functions on phase space. Some inequalities for Wigner functions on phase space are proven. A brief discussion of the classical limit obtained through dilations...
Energy Technology Data Exchange (ETDEWEB)
J.T. Birkholzer
2004-11-01
This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package
International Nuclear Information System (INIS)
1987-01-01
The document contains abstracts of 24 review papers, 24 invited papers, 24 oral contributions and 120 posters. 10 review papers summarize the status of laser fusion research and progress in high-power laser facilities in major world laboratories. Four papers review research programs (laser-matter interaction studies and X-ray source development) based on KrF laser systems. Other review papers discuss the problems of laser energy conversion into X-rays in laser-heated cavities, X-ray lasing at shorter wavelengths, optimization of targets for inertial fusion. Two review papers are devoted to light ion fusion. The subjects of most invited papers are special problems of current laser plasma research, such as hot electron generation, nonlinear resonance absorption, energy accumulation limits, pellet ignition, conversion of laser light into X-rays, high-pressure plasma generation. Three invited papers review laser plasma research in Czechoslovakia, Poland and Spain. One paper suggests a new method of producing muonic superdense matter. The remaining inivited papers deal with the progress in XUV lasers and with laser plasma applications for further laser development. Of the papers accepted for oral presentation 12 papers discuss various problems of laser-plasma interaction; 4 papers deal with laser targets, 4 papers with laser-initiated X-ray sources, 3 papers with the diagnostics of laser-produced plasma. The last oral contribution presents the main principles of the excimer laser theory. The largest group of posters is related to laser-plasma interaction and energy absorption problems, to laser-target interaction and various methods of laser plasma diagnostics. The other posters deal with plasma applications in laser development, plasma mirrors, Brillouin and Raman scattering, X-ray emission, harmonic generation, electron acceleration, production of high-Z plasmas and other related problems. (J.U.)
International Nuclear Information System (INIS)
J.T. Birkholzer
2004-01-01
This model report documents the abstraction of drift seepage, conducted to provide seepage-relevant parameters and their probability distributions for use in Total System Performance Assessment for License Application (TSPA-LA). Drift seepage refers to the flow of liquid water into waste emplacement drifts. Water that seeps into drifts may contact waste packages and potentially mobilize radionuclides, and may result in advective transport of radionuclides through breached waste packages [''Risk Information to Support Prioritization of Performance Assessment Models'' (BSC 2003 [DIRS 168796], Section 3.3.2)]. The unsaturated rock layers overlying and hosting the repository form a natural barrier that reduces the amount of water entering emplacement drifts by natural subsurface processes. For example, drift seepage is limited by the capillary barrier forming at the drift crown, which decreases or even eliminates water flow from the unsaturated fractured rock into the drift. During the first few hundred years after waste emplacement, when above-boiling rock temperatures will develop as a result of heat generated by the decay of the radioactive waste, vaporization of percolation water is an additional factor limiting seepage. Estimating the effectiveness of these natural barrier capabilities and predicting the amount of seepage into drifts is an important aspect of assessing the performance of the repository. The TSPA-LA therefore includes a seepage component that calculates the amount of seepage into drifts [''Total System Performance Assessment (TSPA) Model/Analysis for the License Application'' (BSC 2004 [DIRS 168504], Section 6.3.3.1)]. The TSPA-LA calculation is performed with a probabilistic approach that accounts for the spatial and temporal variability and inherent uncertainty of seepage-relevant properties and processes. Results are used for subsequent TSPA-LA components that may handle, for example, waste package corrosion or radionuclide transport
Summer 2015 Internship Abstract
Smith, Courtney
2015-01-01
Green fluorescent protein (GFP) visually shows the expression of proteins by fluorescing when exposed to certain wavelengths of light. The GFP in this experiment was used to identify cells actively releasing viruses. The experiment focused on the effect of microgravity on the GFP expression of Akata B-cells infected with Epstein Barr Virus (EBV). Two flasks were prepared with 30 million cells each and two bioreactors were prepared with 50 million cells each. All four cultures were incubated for 16 days and fed every four days. Cellometer readings were taken on the feeding days to find cell size, viability, and GFP expression. In addition, the cells were treated with Propodium monoazide (PMA) and run through real time PCR to determine viral load on the feeding days. On the International Space Station air samples are taken to analyze the bacterial and fungal organisms in the air. The Sartorius Portable Airport is being investigated for potential use on the ISS to analyze for viral content in the air. Multiple samples were taken around Johnson Space Center building 37 and in Clear Lake Pediatric Clinic. The filter used was the gelatin membrane filter and the DNA was extracted directly from the filter. The DNA was then run through real time PCR for Varicella Zoster Virus (VZV) and EBV as well as GAPDH to test for the presence of DNA. The results so far have shown low DNA yield and no positive results for VZV or EBV. Further inquiry involves accurately replicating an atmosphere with high viral load from saliva as would be found on the ISS to run the air sampler in. Another line of research is stress hormones that may be correlated to the reactivation of latent viruses. The stress hormones from saliva samples are analyzed rather than blood samples. The quantity found in saliva shows the quantity of the hormones actually attached to cells and causing a reaction, whereas in the blood the quantity of hormones is the total amount released to cause a reaction. The particular
Thomas Leps Internship Abstract
Leps, Thomas
2016-01-01
An optical navigation system is being flown as the backup system to the primary Deep Space Network telemetry for navigation and guidance purposes on Orion. This is required to ensure Orion can recover from a loss of communication, which would simultaneously cause a loss of DSN telemetry. Images taken of the Moon and Earth are used to give range and position information to the navigation computer for trajectory calculations and maneuver execution. To get telemetry data from these images, the size and location of the moon need to be calculated with high accuracy and precision. The reentry envelope for the Orion EM-1 mission requires the centroid and radius of the moon images to be determined within 1/3 of a pixel 3 sigma. In order to ensure this accuracy and precision can be attained, I was tasked with building precise dot grid images for camera calibration as well as building a hardware in the loop test stand for flight software and hardware proofing. To calibrate the Op-Nav camera a dot grid is imaged with the camera, the error between the image dot location and the actual dot location can be used to build a distortion map of the camera and lens system so that images can be fixed to display truth locations. To build the dot grid images I used the Electro Optics Lab optical bench Bright Object Simulator System, and gimbal. The gimbal was slewed to a series of elevations and azimuths. An image of the collimated single point light source was then taken at each position. After a series of 99 images were taken at different locations the single light spots were extracted from each image and added to a composite image containing all 99 points. During the development of these grids it was noticed that an intermittent error in the artificial "star" locations occurred. Prior to the summer this error was attributed to the gimbal having glitches in it's pointing direction and was going to be replaced, however after further examining the issue I determined it to be a software
Lie-algebra expansions, Chern Simons theories and the Einstein Hilbert Lagrangian
Edelstein, José D.; Hassaïne, Mokhtar; Troncoso, Ricardo; Zanelli, Jorge
2006-09-01
Starting from gravity as a Chern-Simons action for the AdS algebra in five dimensions, it is possible to modify the theory through an expansion of the Lie algebra that leads to a system consisting of the Einstein-Hilbert action plus non-minimally coupled matter. The modified system is gauge invariant under the Poincaré group enlarged by an Abelian ideal. Although the resulting action naively looks like general relativity plus corrections due to matter sources, it is shown that the non-minimal couplings produce a radical departure from GR. Indeed, the dynamics is not continuously connected to the one obtained from Einstein-Hilbert action. In a matter-free configuration and in the torsionless sector, the field equations are too strong a restriction on the geometry as the metric must satisfy both the Einstein and pure Gauss-Bonnet equations. In particular, the five-dimensional Schwarzschild geometry fails to be a solution; however, configurations corresponding to a brane-world with positive cosmological constant on the worldsheet are admissible when one of the matter fields is switched on. These results can be extended to higher odd dimensions.
Optimization of the End Effect of Hilbert-Huang transform (HHT)
LV, Chenhuan; ZHAO, Jun; WU, Chao; GUO, Tiantai; CHEN, Hongjiang
2017-05-01
In fault diagnosis of rotating machinery, Hilbert-Huang transform (HHT) is often used to extract the fault characteristic signal and analyze decomposition results in time-frequency domain. However, end effect occurs in HHT, which leads to a series of problems such as modal aliasing and false IMF (Intrinsic Mode Function). To counter such problems in HHT, a new method is put forward to process signal by combining the generalized regression neural network (GRNN) with the boundary local characteristic-scale continuation (BLCC). Firstly, the improved EMD (Empirical Mode Decomposition) method is used to inhibit the end effect problem that appeared in conventional EMD. Secondly, the generated IMF components are used in HHT. Simulation and measurement experiment for the cases of time domain, frequency domain and related parameters of Hilbert-Huang spectrum show that the method described here can restrain the end effect compared with the results obtained through mirror continuation, as the absolute percentage of the maximum mean of the beginning end point offset and the terminal point offset are reduced from 30.113% and 27.603% to 0.510% and 6.039% respectively, thus reducing the modal aliasing, and eliminating the false IMF components of HHT. The proposed method can effectively inhibit end effect, reduce modal aliasing and false IMF components, and show the real structure of signal components accurately.
Bearing fault detection utilizing group delay and the Hilbert-Huang transform
Energy Technology Data Exchange (ETDEWEB)
Jin, Shuai; Lee, Sang-Kwon [Inha University, Incheon (Korea, Republic of)
2017-03-15
Vibration signals measured from a mechanical system are useful to detect system faults. Signal processing has been used to extract fault information in bearing systems. However, a wide vibration signal frequency band often affects the ability to obtain the effective fault features. In addition, a few oscillation components are not useful at the entire frequency band in a vibration signal. By contrast, useful fatigue information can be embedded in the noise oscillation components. Thus, a method to estimate which frequency band contains fault information utilizing group delay was proposed in this paper. Group delay as a measure of phase distortion can indicate the phase structure relationship in the frequency domain between original (with noise) and denoising signals. We used the empirical mode decomposition of a Hilbert-Huang transform to sift the useful intrinsic mode functions based on the results of group delay after determining the valuable frequency band. Finally, envelope analysis and the energy distribution after the Hilbert transform were used to complete the fault diagnosis. The practical bearing fault data, which were divided into inner and outer race faults, were used to verify the efficiency and quality of the proposed method.
From Kant to Hilbert a source book in the foundations of mathematics
Ewald, William Bragg
1996-01-01
This two-volume work brings together a comprehensive selection of mathematical works from the period 1707-1930. During this time the foundations of modern mathematics were laid, and From Kant to Hilbert provides an overview of the foundational work in each of the main branches of mathmeatics with narratives showing how they were linked. Now available as a separate volume. - ;Immanuel Kant''s Critique of Pure Reason is widely taken to be the starting point of the modern period of mathematics while David Hilbert was the last great mainstream mathematician to pursue important nineteenth cnetury ideas. This two-volume work provides an overview of this important era of mathematical research through a carefully chosen selection of articles. They provide an insight into the foundations of each of the main branches of mathematics--algebra, geometry, number. theory, analysis, logic and set theory--with narratives to show how they are linked. Classic works by Bolzano, Riemann, Hamilton, Dedekind, and Poincare are repro...
The solution of the sixth Hilbert problem: the ultimate Galilean revolution.
D'Ariano, Giacomo Mauro
2018-04-28
I argue for a full mathematization of the physical theory, including its axioms, which must contain no physical primitives. In provocative words: 'physics from no physics'. Although this may seem an oxymoron, it is the royal road to keep complete logical coherence, hence falsifiability of the theory. For such a purely mathematical theory the physical connotation must pertain only the interpretation of the mathematics, ranging from the axioms to the final theorems. On the contrary, the postulates of the two current major physical theories either do not have physical interpretation (as for von Neumann's axioms for quantum theory), or contain physical primitives as 'clock', 'rigid rod', 'force', 'inertial mass' (as for special relativity and mechanics). A purely mathematical theory as proposed here, though with limited (but relentlessly growing) domain of applicability, will have the eternal validity of mathematical truth. It will be a theory on which natural sciences can firmly rely. Such kind of theory is what I consider to be the solution of the sixth Hilbert problem. I argue that a prototype example of such a mathematical theory is provided by the novel algorithmic paradigm for physics, as in the recent information-theoretical derivation of quantum theory and free quantum field theory.This article is part of the theme issue 'Hilbert's sixth problem'. © 2018 The Author(s).
Directory of Open Access Journals (Sweden)
Avdakovic Samir
2014-08-01
Full Text Available Analysis of power consumption presents a very important issue for power distribution system operators. Some power system processes such as planning, demand forecasting, development, etc.., require a complete understanding of behaviour of power consumption for observed area, which requires appropriate techniques for analysis of available data. In this paper, two different time-frequency techniques are applied for analysis of hourly values of active and reactive power consumption from one real power distribution transformer substation in urban part of Sarajevo city. Using the continuous wavelet transform (CWT with wavelet power spectrum and global wavelet spectrum some properties of analysed time series are determined. Then, empirical mode decomposition (EMD and Hilbert-Huang Transform (HHT are applied for the analyses of the same time series and the results showed that both applied approaches can provide very useful information about the behaviour of power consumption for observed time interval and different period (frequency bands. Also it can be noticed that the results obtained by global wavelet spectrum and marginal Hilbert spectrum are very similar, thus confirming that both approaches could be used for identification of main properties of active and reactive power consumption time series.
HILBERT-PÓLYA Conjecture, Zeta Functions and Bosonic Quantum Field Theories
Andrade, Julio C.
2013-07-01
The original Hilbert and Pólya conjecture is the assertion that the nontrivial zeros of the Riemann zeta function can be the spectrum of a self-adjoint operator. So far no such operator was found. However, the suggestion of Hilbert and Pólya, in the context of spectral theory, can be extended to approach other problems and so it is natural to ask if there is a quantum mechanical system related to other sequences of numbers which are originated and motivated by Number Theory. In this paper, we show that the functional integrals associated with a hypothetical class of physical systems described by self-adjoint operators associated with bosonic fields whose spectra is given by three different sequence of numbers cannot be constructed. The common feature of the sequence of numbers considered here, which causes the impossibility of zeta regularizations, is that the various Dirichlet series attached to such sequences — such as those which are sums over "primes" of (norm P)-s have a natural boundary, i.e. they cannot be continued beyond the line Re(s) = 0. The main argument is that once the regularized determinant of a Laplacian is meromorphic in s, it follows that the series considered above cannot be a regularized determinant. In other words, we show that the generating functional of connected Schwinger functions of the associated quantum field theories cannot be constructed.
Prediction of unknown deep foundation lengths using the Hilbert Huang Transform (HHT
Directory of Open Access Journals (Sweden)
Ahmed T.M. Farid
2012-08-01
Full Text Available Prediction of unknown deep foundation embedment depth is a great deal nowadays, especially in case of upgrading or rehabilitation of old structures. Many old bridges and marine or pier structures in the United States are established using deep foundations system of timber piles and their foundation records do not exist. Non-Destructive Testing (NDT or Non-Destructive Evaluation (NDE method for a great variety of materials and structures has become an integral part of many tests. However, the process of testing long piles, deeply embedded in the ground, is more complex than (NDT of the other structural materials. This paper summarizes some of the most common non-destructive test methods for deep foundations and presents a new method called the Hilbert Huang Transform (HHT. This Hilbert Huang Transform (HHT method is used now by a wide range in a different health monitoring of many systems. In this paper, some field tests on the timber Piles of one bridge at North Carolina was performed to verify the using the (HHT method for predicting the embedded depth of the unknown piles. Percentage of the accuracy achieved using HHT method for pile length compared to the actual pile length data was performed. Finally, a recommendation is presented for the limitation of using this new method as a new non-destructive method for deep foundations.
Sridharan, Shamira; Li, Yanfen; Bhaduri, Basanta; Majeed, Hassaan; Dupenloup, Paul; Levine, Alex; Kilian, Kristopher A.; Popescu, Gabriel
2016-03-01
Traction force microscopy is the most widely used technique for studying the forces exerted by cells on deformable substrates. However, the method is computationally intense and cells have to be detached from the substrate prior to measuring the displacement map. We have developed a new method, referred to as Hilbert phase dynamometry (HPD), which yields real-time force fields and, simultaneously, cell dry mass and growth information. HPD operates by imaging cells on a deformable substrate that is patterned with a grid of fluorescent proteins. A Hilbert transform is used to extract the phase map associated with the grid deformation, which provides the displacement field. By combining this information with substrate stiffness, an elasticity model was developed to measure forces exerted by cells with high spatial resolution. In our study, we prepared 10kPa gels and them with a 2-D grid of FITC-conjugated fibrinogen/fibronectin mixture, an extracellular matrix protein to which cells adhere. We cultured undifferentiated mesenchymal stem cells (MSC), and MSCs that were in the process of undergoing adipogenesis and osteogenesis. The cells were measured over the course of 24 hours using Spatial Light Interference Microscopy (SLIM) and wide-field epi-fluorescence microscopy allowing us to simultaneously measure cell growth and the forces exerted by the cells on the substrate.
Directory of Open Access Journals (Sweden)
Yaqeen S Mezaal
Full Text Available This paper presents new Wide Bandpass Filter (WBPF and Narrow Bandstop Filter (NBSF incorporating two microstrip resonators, each resonator is based on 2nd iteration of Hilbert fractal geometry. The type of filter as pass or reject band has been adjusted by coupling gap parameter (d between Hilbert resonators using a substrate with a dielectric constant of 10.8 and a thickness of 1.27 mm. Numerical simulation results as well as a parametric study of d parameter on filter type and frequency responses are presented and studied. WBPF has designed at resonant frequencies of 2 and 2.2 GHz with a bandwidth of 0.52 GHz, -28 dB return loss and -0.125 dB insertion loss while NBSF has designed for electrical specifications of 2.37 GHz center frequency, 20 MHz rejection bandwidth, -0.1873 dB return loss and 13.746 dB insertion loss. The proposed technique offers a new alternative to construct low-cost high-performance filter devices, suitable for a wide range of wireless communication systems.
Hytönen, Tuomas; Veraar, Mark; Weis, Lutz
The present volume develops the theory of integration in Banach spaces, martingales and UMD spaces, and culminates in a treatment of the Hilbert transform, Littlewood-Paley theory and the vector-valued Mihlin multiplier theorem. Over the past fifteen years, motivated by regularity problems in evolution equations, there has been tremendous progress in the analysis of Banach space-valued functions and processes. The contents of this extensive and powerful toolbox have been mostly scattered around in research papers and lecture notes. Collecting this diverse body of material into a unified and accessible presentation fills a gap in the existing literature. The principal audience that we have in mind consists of researchers who need and use Analysis in Banach Spaces as a tool for studying problems in partial differential equations, harmonic analysis, and stochastic analysis. Self-contained and offering complete proofs, this work is accessible to graduate students and researchers with a background in functional an...
Hytönen, Tuomas; Veraar, Mark; Weis, Lutz
2016-01-01
The present volume develops the theory of integration in Banach spaces, martingales and UMD spaces, and culminates in a treatment of the Hilbert transform, Littlewood-Paley theory and the vector-valued Mihlin multiplier theorem. Over the past fifteen years, motivated by regularity problems in evolution equations, there has been tremendous progress in the analysis of Banach space-valued functions and processes. The contents of this extensive and powerful toolbox have been mostly scattered around in research papers and lecture notes. Collecting this diverse body of material into a unified and accessible presentation fills a gap in the existing literature. The principal audience that we have in mind consists of researchers who need and use Analysis in Banach Spaces as a tool for studying problems in partial differential equations, harmonic analysis, and stochastic analysis. Self-contained and offering complete proofs, this work is accessible to graduate students and researchers with a background in functional an...
1986 annual information meeting. Abstracts
International Nuclear Information System (INIS)
1986-01-01
Abstracts are presented for the following papers: Geohydrological Research at the Y-12 Plant (C.S. Haase); Ecological Impacts of Waste Disposal Operations in Bear Creek Valley Near the Y-12 Plant (J.M. Loar); Finite Element Simulation of Subsurface Contaminant Transport: Logistic Difficulties in Handling Large Field Problems (G.T. Yeh); Dynamic Compaction of a Radioactive Waste Burial Trench (B.P. Spalding); Comparative Evaluation of Potential Sites for a High-Level Radioactive Waste Repository (E.D. Smith); Changing Priorities in Environmental Assessment and Environmental Compliance (R.M. Reed); Ecology, Ecotoxicology, and Ecological Risk Assessment (L.W. Barnthouse); Theory and Practice in Uncertainty Analysis from Ten Years of Practice (R.H. Gardner); Modeling Landscape Effects of Forest Decline (V.H. Dale); Soil Nitrogen and the Global Carbon Cycle (W.M. Post); Maximizing Wood Energy Production in Short-Rotation Plantations: Effect of Initial Spacing and Rotation Length (L.L. Wright); and Ecological Communities and Processes in Woodland Streams Exhibit Both Direct and Indirect Effects of Acidification (J.W. Elwood)
A first graduate course in abstract algebra
Wickless, WJ
2004-01-01
Since abstract algebra is so important to the study of advanced mathematics, it is critical that students have a firm grasp of its principles and underlying theories before moving on to further study. To accomplish this, they require a concise, accessible, user-friendly textbook that is both challenging and stimulating. A First Graduate Course in Abstract Algebra is just such a textbook.Divided into two sections, this book covers both the standard topics (groups, modules, rings, and vector spaces) associated with abstract algebra and more advanced topics such as Galois fields, noncommutative rings, group extensions, and Abelian groups. The author includes review material where needed instead of in a single chapter, giving convenient access with minimal page turning. He also provides ample examples, exercises, and problem sets to reinforce the material. This book illustrates the theory of finitely generated modules over principal ideal domains, discusses tensor products, and demonstrates the development of det...
Exoplanet Observing: from Art to Science (Abstract)
Conti, D. M.; Gleeson, J.
2017-12-01
(Abstract only) This paper will review the now well-established best practices for conducting high precision exoplanet observing with small telescopes. The paper will also review the AAVSO's activities in promoting these best practices among the amateur astronomer community through training material and online courses, as well as through the establishment of an AAVSO Exoplanet Database. This latter development will be an essential element in supporting followup exoplanet observations for upcoming space telescope missions such as TESS and JWST.
Space and time as outcome of ``decoherence`` in an expanding universe
Energy Technology Data Exchange (ETDEWEB)
Chew, G.F.
1992-11-01
This paper discusses a quantum-cosmological model. The model avoids a priori classical ideas, even spacetime, by invoking a pair of established general principles that relate to each other: (a) Parameter largeness can endow physical approximations with accuracy; and (b) Coherent states labeled by large parameters provide a quantum basis for classical ideas. Generally speaking, the technical term `coherent state` refers to a special category of Hilbert-space vector that relates to some Lie group unitarily representable within Hilbert space. In the Hilbert space of the quantum-cosmological model discussed, labels on basis vectors lack physical interpretation, but groups unitarily represented include not only the Heisenberg-Weyl group but the Poincare group. Corresponding large-parameter coherent states are interpretable in terms of events and particles: a quantam-based meaning of classical objective reality in 3+1 spacetime is thereby achievable.
Space and time as outcome of decoherence'' in an expanding universe
Energy Technology Data Exchange (ETDEWEB)
Chew, G.F.
1992-11-01
This paper discusses a quantum-cosmological model. The model avoids a priori classical ideas, even spacetime, by invoking a pair of established general principles that relate to each other: (a) Parameter largeness can endow physical approximations with accuracy; and (b) Coherent states labeled by large parameters provide a quantum basis for classical ideas. Generally speaking, the technical term coherent state' refers to a special category of Hilbert-space vector that relates to some Lie group unitarily representable within Hilbert space. In the Hilbert space of the quantum-cosmological model discussed, labels on basis vectors lack physical interpretation, but groups unitarily represented include not only the Heisenberg-Weyl group but the Poincare group. Corresponding large-parameter coherent states are interpretable in terms of events and particles: a quantam-based meaning of classical objective reality in 3+1 spacetime is thereby achievable.
Grounding abstractness: Abstract concepts and the activation of the mouth
Directory of Open Access Journals (Sweden)
Anna M Borghi
2016-10-01
Full Text Available One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth. While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts.
Grounding Abstractness: Abstract Concepts and the Activation of the Mouth.
Borghi, Anna M; Zarcone, Edoardo
2016-01-01
One key issue for theories of cognition is how abstract concepts, such as freedom, are represented. According to the WAT (Words As social Tools) proposal, abstract concepts activate both sensorimotor and linguistic/social information, and their acquisition modality involves the linguistic experience more than the acquisition of concrete concepts. We report an experiment in which participants were presented with abstract and concrete definitions followed by concrete and abstract target-words. When the definition and the word matched, participants were required to press a key, either with the hand or with the mouth. Response times and accuracy were recorded. As predicted, we found that abstract definitions and abstract words yielded slower responses and more errors compared to concrete definitions and concrete words. More crucially, there was an interaction between the target-words and the effector used to respond (hand, mouth). While responses with the mouth were overall slower, the advantage of the hand over the mouth responses was more marked with concrete than with abstract concepts. The results are in keeping with grounded and embodied theories of cognition and support the WAT proposal, according to which abstract concepts evoke linguistic-social information, hence activate the mouth. The mechanisms underlying the mouth activation with abstract concepts (re-enactment of acquisition experience, or re-explanation of the word meaning, possibly through inner talk) are discussed. To our knowledge this is the first behavioral study demonstrating with real words that the advantage of the hand over the mouth is more marked with concrete than with abstract concepts, likely because of the activation of linguistic information with abstract concepts.
Nuclear works. Book of abstracts
International Nuclear Information System (INIS)
Candel, Danielle; Calberg-Challot, Marie; Alexander, Catherine; Bergsman, Anne; Meyer, Morgan; Taebi, Behnam; Kloosterman, Jan Leen; Kelfaoui, Mahdi; Gingras, Yves; Laborie, Leonard; Beltran, Alain; Bouvier, Yves; Raineau, Laurence; Poirot-Delpech, Sophie; Ollivon, Franck; Mueller, Birgit; Lemarchand, Frederick; Rivat, Emmanuel; Mormont, Marc; Aparicio, Luis; Fassert, Christine; Lehtonen, Markku; Billet, Philippe; Girard, Berenice; Fournier, Pierre; Marion, Richard; Lot, Nicolas
2012-01-01
The interdisciplinary conference 'How can the social sciences help us understand the nuclear world?' seeks to reassess the relations between nuclear and social science research. It has two objectives. First, it seeks to take stock of and build on existing research by making explicit the theoretical approaches, the research methods, the difficulties met by researchers and by possibly identifying aspects of the nuclear phenomenon that may have been neglected or left out by existing research. Second, it wishes to question the relevance of social science to contemporary nuclear debates and policy making. The conference was organized in 6 sessions dealing with: 1 - Nuclear discourses - Contents and legitimacies: Nuclear terminology: from the dictionary to industrial practices (Danielle Candel, Marie Calberg-Challot), The problem of recognizing nuclear objects (Catherine Alexander), Demonstrating safety (Anne Bergsman, Morgan Meyer), Designing for nuclear safety, security and sustainability: a philosophical discourse of the nuclear reactor (Behnam Taebi, Jan Leen Kloosterman); 2 - History, time and space. Tropes of nuclear activity: The Gentilly-1 NPP history: a technological failure? (Mahdi Kelfaoui, Yves Gingras), Nuclear history: experience and research prospects (Leonard Laborie, Yves Bouvier, Alain Beltran), Temporality clash in front of radioactive wastes disposal (Laurence Raineau, Sophie Poirot-Delpech), Canadian nuclear from the standpoint of territoriality: how a NPP shapes space? (Franck Ollivon); 3 - Citizen mobilizations and the experience of disaster: 'We could make a moonscape out of the whole country...' Anti-Nuclear Activism at the Czech - Austrian Border (Birgit Mueller), From a catastrophe to the other: living with nuclear (Frederick Lemarchand), Nuclear contestation: between information, confrontation and political communication - 1970-2010 (Emmanuel Rivat); 4 - Social science meets the nuclear industry: Renegotiating repository safety: the history of
Mechanical Engineering Department technical abstracts
International Nuclear Information System (INIS)
Denney, R.M.
1982-01-01
The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts
Mechanical Engineering Department technical abstracts
Energy Technology Data Exchange (ETDEWEB)
Denney, R.M. (ed.)
1982-07-01
The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts.
Logical Full Abstraction and PCF
Longley, John R; Plotkin, Gordon
2000-01-01
We introduce the concept of logical full abstraction, generalising the usual equational notion. We consider the language PCF and two extensions with “parallel” operations. The main result is that, for standard interpretations, logical full abstraction is equivalent to equational full abstraction together with universality; the proof involves constructing enumeration operators. We also consider restrictions on logical complexity and on the level of types.
Evaluation of Stress Using Ultrasonic Technique Based on Hilbert-Huang Transform
International Nuclear Information System (INIS)
He, Q; Zhang, H J; Zhou, H L
2006-01-01
Pressures vessel are widely used in the modern industry. It is important to measure pressure of vessels. It has been proved that the change of ultrasonic velocity can be used to detect the stress of the material, and the velocity change can be obtained by estimating the time delay of two ultrasonic pulses. In this paper, the Rayleigh wave is selected as the ultrasonic pulse. Because the Rayleigh wave usually contains noise which deteriorates the estimation precision of the time delay, a signal processing method has to be used. Compared with the continuous wavelet transform, the correlative time estimation method based on the Hilbert-Huang Transform is presented in order to calculate the transit time difference. The experiments results show that this method can improve the accuracy of the time estimation
Noether Current of the Surface Term of Einstein-Hilbert Action, Virasoro Algebra, and Entropy
Directory of Open Access Journals (Sweden)
Bibhas Ranjan Majhi
2013-01-01
Full Text Available A derivation of Noether current from the surface term of Einstein-Hilbert action is given. We show that the corresponding charge, calculated on the horizon, is related to the Bekenstein-Hawking entropy. Also using the charge, the same entropy is found based on the Virasoro algebra and Cardy formula approach. In this approach, the relevant diffeomorphisms are found by imposing a very simple physical argument: diffeomorphisms keep the horizon structure invariant. This complements similar earlier results (Majhi and Padmanabhan (2012 (arXiv:1204.1422 obtained from York-Gibbons-Hawking surface term. Finally we discuss the technical simplicities and improvements over the earlier attempts and also various important physical implications.
Multichannel photonic Hilbert transformers based on complex modulated integrated Bragg gratings.
Cheng, Rui; Chrostowski, Lukas
2018-03-01
Multichannel photonic Hilbert transformers (MPHTs) are reported. The devices are based on single compact spiral integrated Bragg gratings on silicon with coupling coefficients precisely modulated by the phase of each grating period. MPHTs with up to nine wavelength channels and a single-channel bandwidth of up to ∼625 GHz are achieved. The potential of the devices for multichannel single-sideband signal generation is suggested. The work offers a new possibility of utilizing wavelength as an extra degree of freedom in designing radio-frequency photonic signal processors. Such multichannel processors are expected to possess improved capacities and a potential to greatly benefit current widespread wavelength division multiplexed systems.
THz-bandwidth photonic Hilbert transformers based on fiber Bragg gratings in transmission.
Fernández-Ruiz, María R; Wang, Lixian; Carballar, Alejandro; Burla, Maurizio; Azaña, José; LaRochelle, Sophie
2015-01-01
THz-bandwidth photonic Hilbert transformers (PHTs) are implemented for the first time, to the best of our knowledge, based on fiber Bragg grating (FBG) technology. To increase the practical bandwidth limitation of FBGs (typically <200 GHz), a superstructure based on two superimposed linearly-chirped FBGs operating in transmission has been employed. The use of a transmission FBG involves first a conversion of the non-minimum phase response of the PHT into a minimum-phase response by adding an anticipated instantaneous component to the desired system temporal impulse response. Using this methodology, a 3-THz-bandwidth integer PHT and a fractional (order 0.81) PHT are designed, fabricated, and successfully characterized.
A Riemann-Hilbert problem for the shape of a body dissolving in flow
Moore, Nick; Huang, Jinzi Mac; Ristroph, Leif; Applied Math Lab, Courant Institute Team
2014-11-01
As is familiar to anyone who has stirred sugar into coffee, fluid flow can enhance the dissolution of solid material. This effect plays an important role in contexts as varied as landscape formation and drug delivery within the body, but such processes are not well understood due to the interaction between evolving surfaces and flow. By performing experiments with hard-candy bodies dissolving in fast flowing water, we find that different initial geometries converge to the same final shape as they vanish. By modeling both the separated flow around the body and the molecular diffusion of material within the boundary layer, we obtain a Riemann-Hilbert problem for the terminal shape. The solution predicts a front surface of nearly constant curvature, in agreement with experimental measurements. Once formed, this geometry dissolves self-similarly in time and vanishes with a power-law predicted by the model.
A nanocrystalline Hilbert phase-plate for phase-contrast transmission electron microscopy.
Dries, M; Hettler, S; Gamm, B; Müller, E; Send, W; Müller, K; Rosenauer, A; Gerthsen, D
2014-04-01
Thin-film-based phase-plates are applied to enhance the contrast of weak-phase objects in transmission electron microscopy. In this work, metal-film-based phase-plates are considered to reduce contamination and electrostatic charging, which up to now limit the application of phase-plates fabricated from amorphous C-films. Their crystalline structure requires a model for the simulation of the effect of crystallinity on the phase-plate properties and the image formation process. The model established in this work is verified by experimental results obtained by the application of a textured nanocrystalline Au-film-based Hilbert phase-plate. Based on the model, it is shown that monocrystalline and textured nanocrystalline phase-plate microstructures of appropriate thickness and crystalline orientation can be a promising approach for phase-contrast transmission electron microscopy. Copyright © 2014 Elsevier B.V. All rights reserved.
Live cell refractometry using Hilbert phase microscopy and confocal reflectance microscopy.
Lue, Niyom; Choi, Wonshik; Popescu, Gabriel; Yaqoob, Zahid; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S
2009-11-26
Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in their native states. We first record full-field optical thickness maps of living cells by Hilbert phase microscopy and then acquire physical thickness maps of the same cells using a custom-built confocal reflectance microscope. Full-field and axially averaged refractive index maps are acquired from the ratio of optical thickness to physical thickness. The accuracy of the axially averaged index measurement is 0.002. This approach can provide novel biological assays of label-free living cells in situ.
Live Cell Refractometry Using Hilbert Phase Microscopy and Confocal Reflectance Microscopy†
Lue, Niyom; Choi, Wonshik; Popescu, Gabriel; Yaqoob, Zahid; Badizadegan, Kamran; Dasari, Ramachandra R.; Feld, Michael S.
2010-01-01
Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in their native states. We first record full-field optical thickness maps of living cells by Hilbert phase microscopy and then acquire physical thickness maps of the same cells using a custom-built confocal reflectance microscope. Full-field and axially averaged refractive index maps are acquired from the ratio of optical thickness to physical thickness. The accuracy of the axially averaged index measurement is 0.002. This approach can provide novel biological assays of label-free living cells in situ. PMID:19803506
Ngo, Nam Quoc; Song, Yufeng; Lin, Bo
2011-02-01
We present the design and analysis of a wideband and tunable optical Hilbert transformer (OHT) using a tunable waveguide-based finite-impulse response (FIR) filter structure by using the digital filter design method and the Remez algorithm. The tunable Nth-order waveguide-based FIR filter, which simply consists of N delay lines, N tunable couplers, N tunable phase shifters and a combiner, can be tuned, by thermally adjusting the tunable couplers and tunable phase shifters, to tune the bandwidth of an OHT using silica-based planar lightwave circuit (PLC) technology. To demonstrate the effectiveness of the method, the simulation results have an excellent agreement with the theoretical predictions. The tunable OHT can function as a wideband and tunable 90° phase shifter and thus has many potential applications. The two unique features of wideband characteristic (up to ~ 2 THz) and tunable bandwidth (THz tuning range) of the proposed OHT cannot be obtained from the existing OHTs.
Design of FIR Hilbert transformers using prescribed subfilters and nested FT technique
Tai, Yang-Lung; Liu, Jie-Cherng; Chou, Hsien-Hsin
2015-07-01
In this article, a transformation (subfilter) for designing finite impulse response (FIR) Hilbert transformers (HTs) is proposed. With our approach, except simple search procedures, neither optimisation nor any filter design algorithm is needed to obtain the transformation. The proposed subfilter requires only two multipliers regardless of the subfilter order. For the frequency transformation design, the purpose of the subfilter is to provide a "rough" shape of the desired HT; the two coefficients of the subfilter can be implemented as the form of sum of power of two (SOPOT) with only a few bits, thus leading to a multiplierless realisation. Moreover, by applying the transformation on the subfilter again, a technique named as nested frequency transformation (nested FT) is introduced. This technique can further reduce the number of multipliers needed in the overall HT.
Riemann-Hilbert technique scattering analysis of metamaterial-based asymmetric 2D open resonators
Kamiński, Piotr M.; Ziolkowski, Richard W.; Arslanagić, Samel
2017-12-01
The scattering properties of metamaterial-based asymmetric two-dimensional open resonators excited by an electric line source are investigated analytically. The resonators are, in general, composed of two infinite and concentric cylindrical layers covered with an infinitely thin, perfect conducting shell that has an infinite axial aperture. The line source is oriented parallel to the cylinder axis. An exact analytical solution of this problem is derived. It is based on the dual-series approach and its transformation to the equivalent Riemann-Hilbert problem. Asymmetric metamaterial-based configurations are found to lead simultaneously to large enhancements of the radiated power and to highly steerable Huygens-like directivity patterns; properties not attainable with the corresponding structurally symmetric resonators. The presented open resonator designs are thus interesting candidates for many scientific and engineering applications where enhanced directional near- and far-field responses, tailored with beam shaping and steering capabilities, are highly desired.
Trusiak, Maciej; Patorski, Krzysztof; Wielgus, Maciej
2012-10-08
Presented method for fringe pattern enhancement has been designed for processing and analyzing low quality fringe patterns. It uses a modified fast and adaptive bidimensional empirical mode decomposition (FABEMD) for the extraction of bidimensional intrinsic mode functions (BIMFs) from an interferogram. Fringe pattern is then selectively reconstructed (SR) taking the regions of selected BIMFs with high modulation values only. Amplitude demodulation and normalization of the reconstructed image is conducted using the spiral phase Hilbert transform (HS). It has been tested using computer generated interferograms and real data. The performance of the presented SR-FABEMD-HS method is compared with other normalization techniques. Its superiority, potential and robustness to high fringe density variations and the presence of noise, modulation and background illumination defects in analyzed fringe patterns has been corroborated.
Differential Galois theory through Riemann-Hilbert correspondence an elementary introduction
Sauloy, Jacques
2017-01-01
Differential Galois theory is an important, fast developing area which appears more and more in graduate courses since it mixes fundamental objects from many different areas of mathematics in a stimulating context. For a long time, the dominant approach, usually called Picard-Vessiot Theory, was purely algebraic. This approach has been extensively developed and is well covered in the literature. An alternative approach consists in tagging algebraic objects with transcendental information which enriches the understanding and brings not only new points of view but also new solutions. It is very powerful and can be applied in situations where the Picard-Vessiot approach is not easily extended. This book offers a hands-on transcendental approach to differential Galois theory, based on the Riemann-Hilbert correspondence. Along the way, it provides a smooth, down-to-earth introduction to algebraic geometry, category theory and tannakian duality. Since the book studies only complex analytic linear differential equat...
Directory of Open Access Journals (Sweden)
Lajmert Paweł
2018-01-01
Full Text Available In the paper a cutting stability in the milling process of nickel based alloy Inconel 625 is analysed. This problem is often considered theoretically, but the theoretical finding do not always agree with experimental results. For this reason, the paper presents different methods for instability identification during real machining process. A stability lobe diagram is created based on data obtained in impact test of an end mill. Next, the cutting tests were conducted in which the axial cutting depth of cut was gradually increased in order to find a stability limit. Finally, based on the cutting force measurements the stability estimation problem is investigated using the recurrence plot technique and Hilbert vibration decomposition method.
Energy spectrum analysis of blast waves based on an improved Hilbert-Huang transform
Li, L.; Wang, F.; Shang, F.; Jia, Y.; Zhao, C.; Kong, D.
2017-05-01
Using the improved Hilbert-Huang transform (HHT), this paper investigates the problems of analysis and interpretation of the energy spectrum of a blast wave. It has been previously established that the energy spectrum is an effective feature by which to characterize a blast wave. In fact, the higher the energy spectra in a frequency band of a blast wave, the greater the damage to a target in the same frequency band. However, most current research focuses on analyzing wave signals in the time domain or frequency domain rather than considering the energy spectrum. We propose here an improved HHT method combined with a wavelet packet to extract the energy spectrum feature of a blast wave. When applying the HHT, the signal is first roughly decomposed into a series of intrinsic mode functions (IMFs) by empirical mode decomposition. The wavelet packet method is then performed on each IMF to eliminate noise on the energy spectrum. Second, a coefficient is introduced to remove unrelated IMFs. The energy of each instantaneous frequency can be derived through the Hilbert transform. The energy spectrum can then be obtained by adding up all the components after the wavelet packet filters and screens them through a coefficient to obtain the effective IMFs. The effectiveness of the proposed method is demonstrated by 12 groups of experimental data, and an energy attenuation model is established based on the experimental data. The improved HHT is a precise method for blast wave signal analysis. For other shock wave signals from blasting experiments, an energy frequency time distribution and energy spectrum can also be obtained through this method, allowing for more practical applications.
African Journals Online (AJOL)
E¢b
direction, which is believed to lead to improved social life and welfare. This means that Ethiopian trade and economic ... holding better market share and customer satisfaction in their products and services. In addition, in both ...... 1995. Dominant Values and Parenting. Styles: Major Limiting Factors on the Development of.
African Journals Online (AJOL)
their effective participation under different socio- ecological constraints (IDRC, 1993;Takyiwa, 1998;. Kinikanwo, 2000; Isiugo-Abanike, 1994; UNO, 1989). The general issue here is to estimate the extent of female participation in ruminant livestock operations with a view to establishing if stereotyping such operations along.
African Journals Online (AJOL)
feasible and sustainable options. ... strategies, specific to the benefits of exclusive breastfeeding as a mechanism to reduce the risk of HIV transmission is urgently needed ... Joyce Beatrice Ballidawa is a lecturer in the Department of Behavioural Sciences at Moi University School of Medicine, Eldoret, a position she has held.
International Nuclear Information System (INIS)
2013-01-01
The power point presentation is about: danger identification, caracterization, evaluation exposition, risk (CAC, 1997; FAO, 2007), European food safety authority, foodrisk organization, pathogens risk ranking, risk reduction, gubernamental responsability
Indian Academy of Sciences (India)
Efforts have also been successfully made to include the study of rock art in the school/ college curriculum so as to help develop awareness amongst the students and general public about the need to preserve this cultural heritage for the posterity and also to highlight its importance in tourism industry. rock art and their ...
Indian Academy of Sciences (India)
... school/ college curriculum so as to help develop awareness amongst the students and general public about the need to preserve this cultural heritage for the posterity and also to highlight its importance in tourism industry. rock art and their chronological sequences to more applied aspects like scientific methods of dating ...
African Journals Online (AJOL)
Francis
Ficus species. Journal of Ethnopharmacology 41: 71-76. Nadkarni KM (1976) Indian Materia Medica. Third edition, Vol I. Popular Prakhasan, Bombay. NCCLS (National Committee for Clinical Laboratory Standards) (1999). Performance standards for antimicrobial susceptibility testing. 9th International Supplement M100- ...
African Journals Online (AJOL)
Getachew
realistic distribution of no-show data in modeling the cost function was considered using data collected from the .... the paper models the cost function based on a realistic probability distributions based on the historical data is a .... Plot of Revenue generated vs. overbooking for two class case (at $500. Compensation Cost ...
African Journals Online (AJOL)
Dr Osondu
2011-10-26
Oct 26, 2011 ... Keywords: Municipal solid waste; Geographic information system; waste bin; optimal location; developing city. Introduction. Over the years, the spatial organization and existing infrastructure of cities in developing countries pose challenges for sustainable solid waste management programs. Much of the ...
African Journals Online (AJOL)
ATTAMAH C. O
Differences in Climate Change Effects and Adaptation Strategies between Male and Female Livestock Entrepreneurs in ... differed from females in the adaptation strategies used in combating climate change and also on their view on ..... also make use of the same farm road whether in good or bad shape. This is in line with.
African Journals Online (AJOL)
Dr Obe
inner forces (bending moments, shearing forces etc) are usually redistributed. Cracks that often appear within the walls of tall buildings during constructions point to this phenomenon. It has also been recognized that foundation engineering is complicated. (1). Also settlement has been accepted as stress induced and time ...
African Journals Online (AJOL)
viral activity has been observed for halofantrine, amodiaquine and mepacrine.” The clinical significance of these findings is uncertain“"”-. There is some evidence that HIV protease inhibitors may alter disease outcomes of colnfected patients.
African Journals Online (AJOL)
was to determine how the natural aerial connec- teracting worker ants from adjacent trees and tions affected'the viability of colonies Oro!. , observing whether fighting took~iplace :(Yar~ra,. IQffginoda in the tree crowns, in the presence of, 1992). Ants of different colonies fight aggres- inimical ants,P" megacephala, 'on the ...
Directory of Open Access Journals (Sweden)
. user
2016-02-01
Full Text Available Introduction: One of the microbiological preparations used for this study was Effective Microorganisms (EM, being a commercial mixture of photosynthesizing bacteria, Actinomycetes, lactic acid bacteria, yeasts and fermenting fungi. The microbiological composition of the EM concentrateincludesStreptomyces albus, Propioni bacterium freudenreichil, Streptococcus lactis, Aspergillus oryzae, Mucor hiemalis, Saccharomycescerevisiae and Candida utilis. Moreover, EM also contains an unspecified amount of Lactobacillus sp. Rhodo pseudomonas sp. and Streptomyces griseus. Effective Microorganisms have a positive effect on the decomposition of organic matter, limiting putrefaction, increasing nitrogen content in the root medium of plants, phosphorus, improving soil fertility and as a result contributing to the growth and development of the root systems of plants. Selection of almond vegetative rootstocks for water stress tolerance is important for almond crop production in arid and semi-arid regions. The study of the eco-morphological characteristics that determine the success of a rootstock in a particular environment is a powerful tool for both agricultural management and breeding purposes. The aim of this work was to select the new rootstocks for water shortage tolerance, impact of water stress as well as Effective Microorganism (EM on morphological characteristics of almond rootstocks. Materials and Methods: In order to select the new rootstocks for water shortage tolerance, impact of water stress as well as EMonmorphologicalcharacteristics of almondrootstocks were studiedin thedepartment ofHorticulture, Ferdowsi University of Mashhad, in 2011-2012. The experiment was carried out with four replications in a completely random blockdesign to study the effects of two concentrations of EM (0 and 1%, three irrigation levels (normal irrigation 100%-control-and irrigation after depletion of 33 and 66% of available water, and four almond rootstocks including GF677 and selected natural hybrid of peach × almond (H1and H2, and almond vegetative rootstock (local control.In this study,EMtreatments for 60 days before stress treatments were applied so that in each irrigation, EM solution to a concentration of one percent was given to half of the experiment pots. Other pots were irrigated equally with normal water. Stress levels were applied from July as follow: full irrigation, watering after unloading 33% and 66% soil moisture availability. In order to evaluate the performance, seedling survival, plant growth, number of leaves, leaf area, root fresh and dry weight and leaves and root length were measured. Results and Discussion: Analysis of variance showed that between rootstock levels across all treatments were significantly differences at 0.01 level of probability. Comparison of means showed that the highest fresh and dry weight and leaf are awere observed forGF677and H1.Rootstockannualgrowth rate was also different. Most of the growth was related to the H1 Rootstocks. Thes urvival ratewas significantly different from the Rootstocks ofGF677,andH1showedthe highestpercentage of survival. The degree of adaptation to drought in varieties of almonds is different. The results showed that changes ingrowthparametersinGF677and H1were observed less often than other rootstocks. Because of strong roots,GF677and H1continue to attract more minerals under stress conditions. Analysis of variance showed that the between irrigation levels for all treatments were significantly different at 0.01 level of probability. Comparison of means showed that among the study traits, the highest amount was obtained from complete irrigation, while irrigationat66 percenthad the least amount. Water stress may directly affect photosyn thesis, through leaf photochemicalprocessorindirectly,byclosing stomata, reducingleaf area and growth. The results showed that the levels of(EM on the leaf surface, leaf number, annual growth, root dry weight and volume were significantly different (p
African Journals Online (AJOL)
BSN
The preservative effect of CO\\\\'pea pods. seeds, husk. and water and ethanol extracts of the seeds and ... preservation of "kindirmo" with water and ethanol extracts of seeds and husk of. CO\\\\'J)Ca for most of the ... Perhaps same may apply in the area of preservatives: plant products may be safer and biologically friendlier.
Indian Academy of Sciences (India)
2017-03-10
Mar 10, 2017 ... TaqMan allelic discrimination assay. .... women). All patients fulfilled the 1987 American College of Rheumatology criteria for RA. (Arnett et al. 1988). A rheumatology university fellow reviewed all clinical data. ... The rs6457617 and rs13192471 were genotyped with a TaqMan 5' allelic discrimination.
International Nuclear Information System (INIS)
1989-09-01
The proceedings contain 106 papers of which 2 fall under the INIS Scope. One concerns seismic risk assessment at radioactive waste repositories in the U.S., the other concerns the possibility of predicting earthquakes from changes in radon 222 levels in selected ground water springs of northern Italy. (M.D.)
Directory of Open Access Journals (Sweden)
abstract abstract
2016-07-01
Full Text Available Introduction: Strawberry (fragaria×ananassa Duch. fruit characterized by short storage life, often estimated last less than one week even under optimum conditions at 8°C. The loss of fruit quality is often caused by gray mold (Botrytis cinerea that is the most frequent reported postharvest disease in strawberry during storage (6. In recent years, considerable attention has given to elimination of synthetic chemical and fungicides application and development of various alternative strategies for controlling fruit and vegetables diseases (2. One strategy is replacement of natural products with plant origin such as essential oil and methyl salicylate (MeSA. Essential oils are volatile, natural and complex compounds characterized by a strong odor formed by aromatic plants in form of secondary metabolites. In nature, essential similar oils that extract from lavender (Lavandula angustifolia play an important role in protection of the plants against pathogen incidence that can be replaced by synthetic fungicides (1, 4 and 14. MeSA is also a volatile natural compound synthesized from salicylic acid which has an important role in the plant defense-mechanism, as well as plant growth and development (5, 19 and 20. Therefore, the main objective of this research was to study the effects of MeSA and lavender essential oil (LEO on decay control caused by Botrytis cinerea as well as post-harvest quality indices of strawberry fruits during cold storage. Material and Methods: First, antifungal activity was studied by using a contact assay (in vitro, which produces hyphal growth inhibition. Briefly, potato dextrose agar (PDA plates were prepared using 8 cm diameter glass petri dishes and inhibitory percentage was determined. For in-vivo assessment of LEO and MeSA effects on Botrytis-caused fungal disease control, the experiment was conducted as factorial in completely randomized design (CRD with 3 replicates. The treatments were 3 concentration of LEO including 0, 500 and 1000 µl L-1 and 3 level of MeSA including 0, 0.1 and 0.2 mM. After treatment, the fruits were inoculated by Botrytis suspension and transferred to storage and quality parameters were evaluated after 7, 14 and 21 days. At each sampling time, disease incidence, weight loss, titratable acidity, pH, soluble solids content, vitamin C and antioxidant activity were measured. Results and Discussion: The results showed that both LEO and MeSA treatments had significant effects on inhibition of mycelium growth within in-vitro condition (p < 0.05. Inhibition rate of mycelium growth significantly improved by LEO and MeSA concentration increase of, (Table 1. At in-vivo assessment, diseases incidence of treated fruits with 500 µl L-1 LEO and 0.1 mM MeSA were 32% and 64% lower than untreated fruits, respectively (Fig. 1 and 2. During storage period, the percentage of infected fruits increased. In addition, LEO and MeSA treatments affected quality parameters of strawberry fruits including titratable acidity, soluble solids content, vitamin C and antioxidant activity. Treated fruits had a high content of soluble solids, vitamin C and antioxidant activity in comparison to untreated fruits (Table 3 and 4. Probably ascorbic acid decreased through fungal infection duo to cell wall break down during storage. Any factors such as essential oil and salicylate that inhibit fungal growth can help preserving vitamin C in stored products. High level of vitamin C and antioxidant activity was observed in treated fruits with 0.1 mM MeSA and 500 µl L-1 LEO. In controlling weight loss of fruits, 0.2 mM of MeSA and 500 µl L-1 of LEO had significant effects, although MeSA was more effective than LEO treatments, possibly due to elimination of respiration rates and fungi infection (Table 4. Therefore, LEO and MeSA with fungicide effects could be replaced with synthetic fungicides in controlling fungal diseases of strawberry and maintain fruits quality during storage. Conclusion: In conclusion, our results showed that LEO and MeSA treatments could be safe and used to prevent infection of strawberry during storage, although LEO was more effective than MeSA treatments. Concentration of 500 μl L-1 of LEO and 0.1 mM MeSA could control fungal infection of fruits during storage. Also, LEO and MeSA treatments can extend shelf life for over the minimum period required to transit strawberries to foreign markets and without affecting quality, adversely. However, future studies are necessary to fully understand the mechanisms by which LEO and MeSA treatments may act as a fungicide and increase their postharvest life.
African Journals Online (AJOL)
PROF. O. E. OSUAGWU
This software template is also of immense benefits to students of different ... connection, there is the potential to track learner's action in a ..... intelligence. This software will be a direct application of artificial intelligence to develop a special authoring system for e- learning that will have the ability to learn. Intelligent authoring ...
DEFF Research Database (Denmark)
Tafdrup, Oliver
2013-01-01
Udgivet som en del af Tidskrifts specialudgivelse om Adorno. http://tidskrift.dk/data/50/Aforismesamling.pdf......Udgivet som en del af Tidskrifts specialudgivelse om Adorno. http://tidskrift.dk/data/50/Aforismesamling.pdf...
African Journals Online (AJOL)
Maru Shete
of voice, power and representation. To avert this situation, poor women in the research area require equal participation in resources sharing and power of decision making, better employment, housing, education, health care and other opportunities for social service opportunities through savings and credit cooperatives.
African Journals Online (AJOL)
Chylous leakage is an unusual complication following anterior spinal surgery. This leakage can occur as a result of traumatic injury to the thoracic duct, the cisterna chyli, or the retroperitoneal lymphatic vessels. We report a case of a 56 year old female with thoracic spine disc prolapses with cord compression. She.