Exact coefficients for higher dimensional operators with sixteen supersymmetries
Energy Technology Data Exchange (ETDEWEB)
Chen, Wei-Ming [Department of Physics and Astronomy, National Taiwan University,Taipei 10617, Taiwan, R.O.C. (China); Huang, Yu-tin [Department of Physics and Astronomy, National Taiwan University,Taipei 10617, Taiwan, R.O.C. (China); School of Natural Sciences, Institute for Advanced Study,Princeton, NJ 08540 (United States); Wen, Congkao [INFN Sezione di Roma “Tor Vergata' ,Via della Ricerca Scientifica, 00133 Roma (Italy)
2015-09-15
We consider constraints on higher-dimensional operators for supersymmetric effective field theories. In four dimensions with maximal supersymmetry and SU(4) R-symmetry, we demonstrate that the coefficients of abelian operators F{sup n} with MHV helicity configurations must satisfy a recursion relation, and are completely determined by that of F{sup 4}. As the F{sup 4} coefficient is known to be one-loop exact, this allows us to derive exact coefficients for all such operators. We also argue that the results are consistent with the SL(2,Z) duality symmetry. Breaking SU(4) to Sp(4), in anticipation for the Coulomb branch effective action, we again find an infinite class of operators whose coefficients are determined exactly. We also consider three-dimensional N=8 as well as six-dimensional N=(2,0),(1,0) and (1,1) theories. In all cases, we demonstrate that the coefficient of dimension-six operator must be proportional to the square of that of dimension-four.
Higher dimensional operator corrections to the goldstino Goldberger-Treiman vertices
International Nuclear Information System (INIS)
Lee, T.
2000-01-01
The goldstino-matter interactions given by the Goldberger-Treiman relations can receive higher dimensional operator corrections of O(q 2 /M 2 ), where M denotes the mass of the mediators through which SUSY breaking is transmitted. These corrections in the gauge mediated SUSY breaking models arise from loop diagrams, and an explicit calculation of such corrections is presented. It is emphasized that the Goldberger-Treiman vertices are valid only below the mediator scale, and at higher energies goldstinos decouple from the MSSM fields. The implication of this fact for gravitino cosmology in GMSB models is mentioned. (orig.)
Araneda, Bernardo
2018-04-01
We present weighted covariant derivatives and wave operators for perturbations of certain algebraically special Einstein spacetimes in arbitrary dimensions, under which the Teukolsky and related equations become weighted wave equations. We show that the higher dimensional generalization of the principal null directions are weighted conformal Killing vectors with respect to the modified covariant derivative. We also introduce a modified Laplace–de Rham-like operator acting on tensor-valued differential forms, and show that the wave-like equations are, at the linear level, appropriate projections off shell of this operator acting on the curvature tensor; the projection tensors being made out of weighted conformal Killing–Yano tensors. We give off shell operator identities that map the Einstein and Maxwell equations into weighted scalar equations, and using adjoint operators we construct solutions of the original field equations in a compact form from solutions of the wave-like equations. We study the extreme and zero boost weight cases; extreme boost corresponding to perturbations of Kundt spacetimes (which includes near horizon geometries of extreme black holes), and zero boost to static black holes in arbitrary dimensions. In 4D our results apply to Einstein spacetimes of Petrov type D and make use of weighted Killing spinors.
On higher-dimensional loop algebras, pseudodifferential operators and Fock space realizations
International Nuclear Information System (INIS)
Westerberg, A.
1997-01-01
We discuss a previously discovered extension of the infinite-dimensional Lie algebra map(M,g) which generalizes the Kac-Moody algebras in 1+1 dimensions and the Mickelsson-Faddeev algebras in 3+1 dimensions to manifolds M of general dimensions. Furthermore, we review the method of regularizing current algebras in higher dimensions using pseudodifferential operator (PSDO) symbol calculus. In particular, we discuss the issue of Lie algebra cohomology of PSDOs and its relation to the Schwinger terms arising in the quantization process. Finally, we apply this regularization method to the algebra with partial success, and discuss the remaining obstacles to the construction of a Fock space representation. (orig.)
Higher dimensional loop quantum cosmology
International Nuclear Information System (INIS)
Zhang, Xiangdong
2016-01-01
Loop quantum cosmology (LQC) is the symmetric sector of loop quantum gravity. In this paper, we generalize the structure of loop quantum cosmology to the theories with arbitrary spacetime dimensions. The isotropic and homogeneous cosmological model in n + 1 dimensions is quantized by the loop quantization method. Interestingly, we find that the underlying quantum theories are divided into two qualitatively different sectors according to spacetime dimensions. The effective Hamiltonian and modified dynamical equations of n + 1 dimensional LQC are obtained. Moreover, our results indicate that the classical big bang singularity is resolved in arbitrary spacetime dimensions by a quantum bounce. We also briefly discuss the similarities and differences between the n + 1 dimensional model and the 3 + 1 dimensional one. Our model serves as a first example of higher dimensional loop quantum cosmology and offers the possibility to investigate quantum gravity effects in higher dimensional cosmology. (orig.)
Instabilities of higher dimensional compactifications
International Nuclear Information System (INIS)
Accetta, F.S.
1987-02-01
Various schemes for cosmological compactification of higher dimensional theories are considered. Possible instabilities which drive the ground state with static internal space to de Sitter-like expansion of all dimensions are discussed. These instabilities are due to semiclassical barrier penetration and classical thermal fluctuations. For the case of the ten dimensional Chapline-Manton action, it is possible to avoid such difficulties by balancing one-loop Casimir corrections against monopole contributions from the field strength H/sub MNP/ and fermionic condensates. 10 refs
Higher dimensional discrete Cheeger inequalities
Directory of Open Access Journals (Sweden)
Anna Gundert
2015-01-01
Full Text Available For graphs there exists a strong connection between spectral and combinatorial expansion properties. This is expressed, e.g., by the discrete Cheeger inequality, the lower bound of which states that $\\lambda(G \\leq h(G$, where $\\lambda(G$ is the second smallest eigenvalue of the Laplacian of a graph $G$ and $h(G$ is the Cheeger constant measuring the edge expansion of $G$. We are interested in generalizations of expansion properties to finite simplicial complexes of higher dimension (or uniform hypergraphs. Whereas higher dimensional Laplacians were introduced already in 1945 by Eckmann, the generalization of edge expansion to simplicial complexes is not straightforward. Recently, a topologically motivated notion analogous to edge expansion that is based on $\\mathbb{Z}_2$-cohomology was introduced by Gromov and independently by Linial, Meshulam and Wallach. It is known that for this generalization there is no direct higher dimensional analogue of the lower bound of the Cheeger inequality. A different, combinatorially motivated generalization of the Cheeger constant, denoted by $h(X$, was studied by Parzanchevski, Rosenthal and Tessler. They showed that indeed $\\lambda(X \\leq h(X$, where $\\lambda(X$ is the smallest non-trivial eigenvalue of the ($(k-1$-dimensional upper Laplacian, for the case of $k$-dimensional simplicial complexes $X$ with complete $(k-1$-skeleton. Whether this inequality also holds for $k$-dimensional complexes with non-com\\-plete$(k-1$-skeleton has been an open question.We give two proofs of the inequality for arbitrary complexes. The proofs differ strongly in the methods and structures employed,and each allows for a different kind of additional strengthening of the original result.
Gravastars with higher dimensional spacetimes
Ghosh, Shounak; Ray, Saibal; Rahaman, Farook; Guha, B. K.
2018-07-01
We present a new model of gravastar in the higher dimensional Einsteinian spacetime including Einstein's cosmological constant Λ. Following Mazur and Mottola (2001, 2004) we design the star with three specific regions, as follows: (I) Interior region, (II) Intermediate thin spherical shell and (III) Exterior region. The pressure within the interior region is equal to the negative matter density which provides a repulsive force over the shell. This thin shell is formed by ultra relativistic plasma, where the pressure is directly proportional to the matter-energy density which does counter balance the repulsive force from the interior whereas the exterior region is completely vacuum assumed to be de Sitter spacetime which can be described by the generalized Schwarzschild solution. With this specification we find out a set of exact non-singular and stable solutions of the gravastar which seems physically very interesting and reasonable.
Higher (odd dimensional quantum Hall effect and extended dimensional hierarchy
Directory of Open Access Journals (Sweden)
Kazuki Hasebe
2017-07-01
Full Text Available We demonstrate dimensional ladder of higher dimensional quantum Hall effects by exploiting quantum Hall effects on arbitrary odd dimensional spheres. Non-relativistic and relativistic Landau models are analyzed on S2k−1 in the SO(2k−1 monopole background. The total sub-band degeneracy of the odd dimensional lowest Landau level is shown to be equal to the winding number from the base-manifold S2k−1 to the one-dimension higher SO(2k gauge group. Based on the chiral Hopf maps, we clarify the underlying quantum Nambu geometry for odd dimensional quantum Hall effect and the resulting quantum geometry is naturally embedded also in one-dimension higher quantum geometry. An origin of such dimensional ladder connecting even and odd dimensional quantum Hall effects is illuminated from a viewpoint of the spectral flow of Atiyah–Patodi–Singer index theorem in differential topology. We also present a BF topological field theory as an effective field theory in which membranes with different dimensions undergo non-trivial linking in odd dimensional space. Finally, an extended version of the dimensional hierarchy for higher dimensional quantum Hall liquids is proposed, and its relationship to quantum anomaly and D-brane physics is discussed.
Higher dimensional homogeneous cosmology in Lyra geometry
Indian Academy of Sciences (India)
1Department of Mathematics, Jadavpur University, Kolkata 700 032, India. 2Khodar ... 1. Introduction. The idea of higher dimensional theory was originated in super string and super gravity .... Equation (7) can easily be integrated to obtain.
Execution spaces for simple higher dimensional automata
DEFF Research Database (Denmark)
Raussen, Martin
2012-01-01
Higher dimensional automata (HDA) are highly expressive models for concurrency in Computer Science, cf van Glabbeek (Theor Comput Sci 368(1–2): 168–194, 2006). For a topologist, they are attractive since they can be modeled as cubical complexes—with an inbuilt restriction for directions of allowa......Higher dimensional automata (HDA) are highly expressive models for concurrency in Computer Science, cf van Glabbeek (Theor Comput Sci 368(1–2): 168–194, 2006). For a topologist, they are attractive since they can be modeled as cubical complexes—with an inbuilt restriction for directions...
Higher-dimensional relativistic-fluid spheres
International Nuclear Information System (INIS)
Patel, L. K.; Ahmedabad, Gujarat Univ.
1997-01-01
They consider the hydrostatic equilibrium of relativistic-fluid spheres for a D-dimensional space-time. Three physically viable interior solutions of the Einstein field equations corresponding to perfect-fluid spheres in a D-dimensional space-time are obtained. When D = 4 they reduce to the Tolman IV solution, the Mehra solution and the Finch-Skea solution. The solutions are smoothly matched with the D-dimensional Schwarzschild exterior solution at the boundary r = a of the fluid sphere. Some physical features and other related details of the solutions are briefly discussed. A brief description of two other new solutions for higher-dimensional perfect-fluid spheres is also given
Orthogonality preserving infinite dimensional quadratic stochastic operators
International Nuclear Information System (INIS)
Akın, Hasan; Mukhamedov, Farrukh
2015-01-01
In the present paper, we consider a notion of orthogonal preserving nonlinear operators. We introduce π-Volterra quadratic operators finite and infinite dimensional settings. It is proved that any orthogonal preserving quadratic operator on finite dimensional simplex is π-Volterra quadratic operator. In infinite dimensional setting, we describe all π-Volterra operators in terms orthogonal preserving operators
Execution spaces for simple higher dimensional automata
DEFF Research Database (Denmark)
Raussen, Martin
Higher Dimensional Automata (HDA) are highly expressive models for concurrency in Computer Science, cf van Glabbeek [26]. For a topologist, they are attractive since they can be modeled as cubical complexes - with an inbuilt restriction for directions´of allowable (d-)paths. In Raussen [25], we...
Higher dimensional time-energy entanglement
International Nuclear Information System (INIS)
Richart, Daniel Lampert
2014-01-01
freedom improves its applicability to long distance quantum communication schemes. By doing that, the intrinsic limitations of other schemes based on the encoding into the momentum and polarization degree of freedom are overcome. This work presents results on a scalable experimental implementation of time-energy encoded higher dimensional states, demonstrating the feasibility of the scheme. Further tools are defined and used to characterize the properties of the prepared quantum states, such as their entanglement, their dimension and their preparation fidelity. Finally, the method of quantum state tomography is used to fully determine the underlying quantum states at the cost of an increased measurement effort and thus operation time. It is at this point that results obtained from the research field of compressed sensing help to decrease the necessary number of measurements. This scheme is compared with an adaptive tomography scheme designed to offer an additional reconstruction speedup. These results display the scalability of the scheme to bipartite dimensions higher than 2 x 8, equivalent to the encoding of quantum information into more than 6 qubits.
Higher dimensional time-energy entanglement
Energy Technology Data Exchange (ETDEWEB)
Richart, Daniel Lampert
2014-07-08
freedom improves its applicability to long distance quantum communication schemes. By doing that, the intrinsic limitations of other schemes based on the encoding into the momentum and polarization degree of freedom are overcome. This work presents results on a scalable experimental implementation of time-energy encoded higher dimensional states, demonstrating the feasibility of the scheme. Further tools are defined and used to characterize the properties of the prepared quantum states, such as their entanglement, their dimension and their preparation fidelity. Finally, the method of quantum state tomography is used to fully determine the underlying quantum states at the cost of an increased measurement effort and thus operation time. It is at this point that results obtained from the research field of compressed sensing help to decrease the necessary number of measurements. This scheme is compared with an adaptive tomography scheme designed to offer an additional reconstruction speedup. These results display the scalability of the scheme to bipartite dimensions higher than 2 x 8, equivalent to the encoding of quantum information into more than 6 qubits.
Thermodynamics of higher dimensional black holes
International Nuclear Information System (INIS)
Accetta, F.S.; Gleiser, M.
1986-05-01
We discuss the thermodynamics of higher dimensional black holes with particular emphasis on a new class of spinning black holes which, due to the increased number of Casimir invariants, have additional spin degrees of freedom. In suitable limits, analytic solutions in arbitrary dimensions are presented for their temperature, entropy, and specific heat. In 5 + 1 and 9 + 1 dimensions, more general forms for these quantities are given. It is shown that the specific heat for a higher dimensional black hole is negative definite if it has only one non-zero spin parameter, regardless of the value of this parameter. We also consider equilibrium configurations with both massless particles and massive string modes. 16 refs., 3 figs
Thermodynamics of higher dimensional black holes
Energy Technology Data Exchange (ETDEWEB)
Accetta, F.S.; Gleiser, M.
1986-05-01
We discuss the thermodynamics of higher dimensional black holes with particular emphasis on a new class of spinning black holes which, due to the increased number of Casimir invariants, have additional spin degrees of freedom. In suitable limits, analytic solutions in arbitrary dimensions are presented for their temperature, entropy, and specific heat. In 5 + 1 and 9 + 1 dimensions, more general forms for these quantities are given. It is shown that the specific heat for a higher dimensional black hole is negative definite if it has only one non-zero spin parameter, regardless of the value of this parameter. We also consider equilibrium configurations with both massless particles and massive string modes. 16 refs., 3 figs.
Perturbations of higher-dimensional spacetimes
Energy Technology Data Exchange (ETDEWEB)
Durkee, Mark; Reall, Harvey S, E-mail: M.N.Durkee@damtp.cam.ac.uk, E-mail: H.S.Reall@damtp.cam.ac.uk [DAMTP, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)
2011-02-07
We discuss linearized gravitational perturbations of higher-dimensional spacetimes. For algebraically special spacetimes (e.g. Myers-Perry black holes), we show that there exist local gauge invariant quantities linear in the metric perturbation. These are the higher-dimensional generalizations of the 4D Newman-Penrose scalars that (in an algebraically special vacuum spacetime) satisfy decoupled equations of motion. We show that decoupling occurs in more than four dimensions if, and only if, the spacetime admits a null geodesic congruence with vanishing expansion, rotation and shear. Decoupling of electromagnetic perturbations occurs under the same conditions. Although these conditions are not satisfied in black hole spacetimes, they are satisfied in the near-horizon geometry of an extreme black hole.
Extended inflation from higher dimensional theories
International Nuclear Information System (INIS)
Holman, R.; Kolb, E.W.; Vadas, S.L.; Wang, Yun.
1990-04-01
The possibility is considered that higher dimensional theories may, upon reduction to four dimensions, allow extended inflation to occur. Two separate models are analayzed. One is a very simple toy model consisting of higher dimensional gravity coupled to a scalar field whose potential allows for a first-order phase transition. The other is a more sophisticated model incorporating the effects of non-trivial field configurations (monopole, Casimir, and fermion bilinear condensate effects) that yield a non-trivial potential for the radius of the internal space. It was found that extended inflation does not occur in these models. It was also found that the bubble nucleation rate in these theories is time dependent unlike the case in the original version of extended inflation
Extended inflation from higher-dimensional theories
International Nuclear Information System (INIS)
Holman, R.; Kolb, E.W.; Vadas, S.L.; Wang, Y.
1991-01-01
We consider the possibility that higher-dimensional theories may, upon reduction to four dimensions, allow extended inflation to occur. We analyze two separate models. One is a very simple toy model consisting of higher-dimensional gravity coupled to a scalar field whose potential allows for a first-order phase transition. The other is a more sophisticated model incorporating the effects of nontrivial field configurations (monopole, Casimir, and fermion bilinear condensate effects) that yield a nontrivial potential for the radius of the internal space. We find that extended inflation does not occur in these models. We also find that the bubble nucleation rate in these theories is time dependent unlike the case in the original version of extended inflation
Spatial infinity in higher dimensional spacetimes
International Nuclear Information System (INIS)
Shiromizu, Tetsuya; Tomizawa, Shinya
2004-01-01
Motivated by recent studies on the uniqueness or nonuniqueness of higher dimensional black hole spacetime, we investigate the asymptotic structure of spatial infinity in n-dimensional spacetimes (n≥4). It turns out that the geometry of spatial infinity does not have maximal symmetry due to the nontrivial Weyl tensor (n-1) C abcd in general. We also address static spacetime and its multipole moments P a 1 a 2 ···a s . Contrasting with four dimensions, we stress that the local structure of spacetimes cannot be unique under fixed multipole moments in static vacuum spacetimes. For example, we consider the generalized Schwarzschild spacetimes which are deformed black hole spacetimes with the same multipole moments as spherical Schwarzschild black holes. To specify the local structure of the static vacuum solution we need some additional information, at least the Weyl tensor (n-2) C abcd at spatial infinity
Multifractal and higher-dimensional zeta functions
International Nuclear Information System (INIS)
Véhel, Jacques Lévy; Mendivil, Franklin
2011-01-01
In this paper, we generalize the zeta function for a fractal string (as in Lapidus and Frankenhuijsen 2006 Fractal Geometry, Complex Dimensions and Zeta Functions: Geometry and Spectra of Fractal Strings (New York: Springer)) in several directions. We first modify the zeta function to be associated with a sequence of covers instead of the usual definition involving gap lengths. This modified zeta function allows us to define both a multifractal zeta function and a zeta function for higher-dimensional fractal sets. In the multifractal case, the critical exponents of the zeta function ζ(q, s) yield the usual multifractal spectrum of the measure. The presence of complex poles for ζ(q, s) indicates oscillations in the continuous partition function of the measure, and thus gives more refined information about the multifractal spectrum of a measure. In the case of a self-similar set in R n , the modified zeta function yields asymptotic information about both the 'box' counting function of the set and the n-dimensional volume of the ε-dilation of the set
Moduli stabilization in higher dimensional brane models
International Nuclear Information System (INIS)
Flachi, Antonino; Pujolas, Oriol; Garriga, Jaume; Tanaka, Takahiro
2003-01-01
We consider a class of warped higher dimensional brane models with topology M x Σ x S 1 /Z 2 , where Σ is a D2 dimensional manifold. Two branes of co-dimension one are embedded in such a bulk space-time and sit at the orbifold fixed points. We concentrate on the case where an exponential warp factor (depending on the distance along the orbifold) accompanies the Minkowski M and the internal space Σ line elements. We evaluate the moduli effective potential induced by bulk scalar fields in these models, and we show that generically this can stabilize the size of the extra dimensions. As an application, we consider a scenario where supersymmetry is broken not far below the cutoff scale, and the hierarchy between the electroweak and the effective Planck scales is generated by a combination of redshift and large volume effects. The latter is efficient due to the shrinking of Σ at the negative tension brane, where matter is placed. In this case, we find that the effective potential can stabilize the size of the extra dimensions (and the hierarchy) without fine tuning, provided that the internal space Σ is flat. (author)
Moduli stabilization in higher dimensional brane models
Energy Technology Data Exchange (ETDEWEB)
Flachi, Antonino; Pujolas, Oriol [IFAE, Campus UAB, 08193 Bellaterra, Barcelona (Spain)]. E-mail: pujolas@ifae.es; Garriga, Jaume [IFAE, Campus UAB, 08193 Bellaterra, Barcelona (Spain); Departament de Fisica Fonamental and C.E.R. en Astrofisica, Fisica de Particules i Cosmologia Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain); Tanaka, Takahiro [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford MA 02155 (United States); Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502 (Japan)
2003-08-01
We consider a class of warped higher dimensional brane models with topology M x {sigma} x S{sup 1}/Z{sub 2}, where {sigma} is a D2 dimensional manifold. Two branes of co-dimension one are embedded in such a bulk space-time and sit at the orbifold fixed points. We concentrate on the case where an exponential warp factor (depending on the distance along the orbifold) accompanies the Minkowski M and the internal space {sigma} line elements. We evaluate the moduli effective potential induced by bulk scalar fields in these models, and we show that generically this can stabilize the size of the extra dimensions. As an application, we consider a scenario where supersymmetry is broken not far below the cutoff scale, and the hierarchy between the electroweak and the effective Planck scales is generated by a combination of redshift and large volume effects. The latter is efficient due to the shrinking of {sigma} at the negative tension brane, where matter is placed. In this case, we find that the effective potential can stabilize the size of the extra dimensions (and the hierarchy) without fine tuning, provided that the internal space {sigma} is flat. (author)
Schuler, Michael; Whitsitt, Seth; Henry, Louis-Paul; Sachdev, Subir; Läuchli, Andreas M
2016-11-18
The low-energy spectra of many body systems on a torus, of finite size L, are well understood in magnetically ordered and gapped topological phases. However, the spectra at quantum critical points separating such phases are largely unexplored for (2+1)D systems. Using a combination of analytical and numerical techniques, we accurately calculate and analyze the low-energy torus spectrum at an Ising critical point which provides a universal fingerprint of the underlying quantum field theory, with the energy levels given by universal numbers times 1/L. We highlight the implications of a neighboring topological phase on the spectrum by studying the Ising* transition (i.e. the transition between a Z_{2} topological phase and a trivial paramagnet), in the example of the toric code in a longitudinal field, and advocate a phenomenological picture that provides qualitative insight into the operator content of the critical field theory.
Higher dimensional supersymmetric quantum mechanics and Dirac ...
Indian Academy of Sciences (India)
We exhibit the supersymmetric quantum mechanical structure of the full 3+1 dimensional Dirac equation considering `mass' as a function of coordinates. Its usefulness in solving potential problems is discussed with speciﬁc examples. We also discuss the `physical' signiﬁcance of the supersymmetric states in this formalism.
Higher-dimensional puncture initial data
International Nuclear Information System (INIS)
Zilhao, Miguel; Ansorg, Marcus; Cardoso, Vitor; Gualtieri, Leonardo; Herdeiro, Carlos; Sperhake, Ulrich; Witek, Helvi
2011-01-01
We calculate puncture initial data, corresponding to single and binary black holes with linear momenta, which solve the constraint equations of D-dimensional vacuum gravity. The data are generated by a modification of the pseudospectral code presented in [M. Ansorg, B. Bruegmann, and W. Tichy, Phys. Rev. D 70, 064011 (2004).] and made available as the TwoPunctures thorn inside the Cactus computational toolkit. As examples, we exhibit convergence plots, the violation of the Hamiltonian constraint as well as the initial data for D=4,5,6,7. These initial data are the starting point to perform high-energy collisions of black holes in D dimensions.
Higher-dimensional Bianchi type-VIh cosmologies
Lorenz-Petzold, D.
1985-09-01
The higher-dimensional perfect fluid equations of a generalization of the (1 + 3)-dimensional Bianchi type-VIh space-time are discussed. Bianchi type-V and Bianchi type-III space-times are also included as special cases. It is shown that the Chodos-Detweiler (1980) mechanism of cosmological dimensional-reduction is possible in these cases.
Higher dimensional generalizations of the SYK model
Energy Technology Data Exchange (ETDEWEB)
Berkooz, Micha [Department of Particle Physics and Astrophysics, Weizmann Institute of Science,Rehovot 7610001 (Israel); Narayan, Prithvi [International Centre for Theoretical Sciences, Hesaraghatta,Bengaluru North, 560 089 (India); Rozali, Moshe [Department of Physics and Astronomy, University of British Columbia,Vancouver, BC V6T 1Z1 (Canada); Simón, Joan [School of Mathematics and Maxwell Institute for Mathematical Sciences, University of Edinburgh,King’s Buildings, Edinburgh EH9 3FD (United Kingdom)
2017-01-31
We discuss a 1+1 dimensional generalization of the Sachdev-Ye-Kitaev model. The model contains N Majorana fermions at each lattice site with a nearest-neighbour hopping term. The SYK random interaction is restricted to low momentum fermions of definite chirality within each lattice site. This gives rise to an ordinary 1+1 field theory above some energy scale and a low energy SYK-like behavior. We exhibit a class of low-pass filters which give rise to a rich variety of hyperscaling behaviour in the IR. We also discuss another set of generalizations which describes probing an SYK system with an external fermion, together with the new scaling behavior they exhibit in the IR.
Fermion tunneling from higher-dimensional black holes
International Nuclear Information System (INIS)
Lin Kai; Yang Shuzheng
2009-01-01
Via the semiclassical approximation method, we study the 1/2-spin fermion tunneling from a higher-dimensional black hole. In our work, the Dirac equations are transformed into a simple form, and then we simplify the fermion tunneling research to the study of the Hamilton-Jacobi equation in curved space-time. Finally, we get the fermion tunneling rates and the Hawking temperatures at the event horizon of higher-dimensional black holes. We study fermion tunneling of a higher-dimensional Schwarzschild black hole and a higher-dimensional spherically symmetric quintessence black hole. In fact, this method is also applicable to the study of fermion tunneling from four-dimensional or lower-dimensional black holes, and we will take the rainbow-Finsler black hole as an example in order to make the fact explicit.
Higher dimensional uniformisation and W-geometry
International Nuclear Information System (INIS)
Govindarajan, S.
1995-01-01
We formulate the uniformisation problem underlying the geometry of W n -gravity using the differential equation approach to W-algebras. We construct W n -space (analogous to superspace in supersymmetry) as an (n-1)-dimensional complex manifold using isomonodromic deformations of linear differential equations. The W n -manifold is obtained by the quotient of a Fuchsian subgroup of PSL(n,R) which acts properly discontinuously on a simply connected domain in bfCP n-1 . The requirement that a deformation be isomonodromic furnishes relations which enable one to convert non-linear W-diffeomorphisms to (linear) diffeomorphisms on the W n -manifold. We discuss how the Teichmueller spaces introduced by Hitchin can then be interpreted as the space of complex structures or the space of projective structures with real holonomy on the W n -manifold. The projective structures are characterised by Halphen invariants which are appropriate generalisations of the Schwarzian. This construction will work for all ''generic'' W-algebras. (orig.)
Higher-order gravity in higher dimensions: geometrical origins of four-dimensional cosmology?
Energy Technology Data Exchange (ETDEWEB)
Troisi, Antonio [Universita degli Studi di Salerno, Dipartimento di Fisica ' ' E.R. Caianiello' ' , Salerno (Italy)
2017-03-15
Determining the cosmological field equations is still very much debated and led to a wide discussion around different theoretical proposals. A suitable conceptual scheme could be represented by gravity models that naturally generalize Einstein theory like higher-order gravity theories and higher-dimensional ones. Both of these two different approaches allow one to define, at the effective level, Einstein field equations equipped with source-like energy-momentum tensors of geometrical origin. In this paper, the possibility is discussed to develop a five-dimensional fourth-order gravity model whose lower-dimensional reduction could provide an interpretation of cosmological four-dimensional matter-energy components. We describe the basic concepts of the model, the complete field equations formalism and the 5-D to 4-D reduction procedure. Five-dimensional f(R) field equations turn out to be equivalent, on the four-dimensional hypersurfaces orthogonal to the extra coordinate, to an Einstein-like cosmological model with three matter-energy tensors related with higher derivative and higher-dimensional counter-terms. By considering the gravity model with f(R) = f{sub 0}R{sup n} the possibility is investigated to obtain five-dimensional power law solutions. The effective four-dimensional picture and the behaviour of the geometrically induced sources are finally outlined in correspondence to simple cases of such higher-dimensional solutions. (orig.)
Charged fluid distribution in higher dimensional spheroidal space-time
Indian Academy of Sciences (India)
A general solution of Einstein field equations corresponding to a charged fluid distribution on the background of higher dimensional spheroidal space-time is obtained. The solution generates several known solutions for superdense star having spheroidal space-time geometry.
Higher dimensional global monopole in Brans–Dicke theory
Indian Academy of Sciences (India)
Keywords. Global monopole; Brans–Dicke theory; higher dimension. PACS Nos 04.20.Jb; 98.80.Bp; 04.50.+h. 1. Introduction. The idea of higher dimensional theory was originated in super string and super gravity the- ories to unify gravity with other fundamental forces in nature. Solutions of Einstein field equations in higher ...
Central subspace dimensionality reduction using covariance operators.
Kim, Minyoung; Pavlovic, Vladimir
2011-04-01
We consider the task of dimensionality reduction informed by real-valued multivariate labels. The problem is often treated as Dimensionality Reduction for Regression (DRR), whose goal is to find a low-dimensional representation, the central subspace, of the input data that preserves the statistical correlation with the targets. A class of DRR methods exploits the notion of inverse regression (IR) to discover central subspaces. Whereas most existing IR techniques rely on explicit output space slicing, we propose a novel method called the Covariance Operator Inverse Regression (COIR) that generalizes IR to nonlinear input/output spaces without explicit target slicing. COIR's unique properties make DRR applicable to problem domains with high-dimensional output data corrupted by potentially significant amounts of noise. Unlike recent kernel dimensionality reduction methods that employ iterative nonconvex optimization, COIR yields a closed-form solution. We also establish the link between COIR, other DRR techniques, and popular supervised dimensionality reduction methods, including canonical correlation analysis and linear discriminant analysis. We then extend COIR to semi-supervised settings where many of the input points lack their labels. We demonstrate the benefits of COIR on several important regression problems in both fully supervised and semi-supervised settings.
Small Aircraft Transportation System, Higher Volume Operations Concept: Normal Operations
Abbott, Terence S.; Jones, Kenneth M.; Consiglio, Maria C.; Williams, Daniel M.; Adams, Catherine A.
2004-01-01
This document defines the Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) concept for normal conditions. In this concept, a block of airspace would be established around designated non-towered, non-radar airports during periods of poor weather. Within this new airspace, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Using onboard equipment and procedures, they would then approach and land at the airport. Departures would be handled in a similar fashion. The details for this operational concept are provided in this document.
On conformal Paneitz curvature equations in higher dimensional spheres
International Nuclear Information System (INIS)
El Mehdi, Khalil
2004-11-01
We study the problem of prescribing the Paneitz curvature on higher dimensional spheres. Particular attention is paid to the blow-up points, i.e. the critical points at infinity of the corresponding variational problem. Using topological tools and a careful analysis of the gradient flow lines in the neighborhood of such critical points at infinity, we prove some existence results. (author)
Electromagnetic field in higher-dimensional black-hole spacetimes
International Nuclear Information System (INIS)
Krtous, Pavel
2007-01-01
A special test electromagnetic field in the spacetime of the higher-dimensional generally rotating NUT-(anti-)de Sitter black hole is found. It is adjusted to the hidden symmetries of the background represented by the principal Killing-Yano tensor. Such an electromagnetic field generalizes the field of charged black hole in four dimensions. In higher dimensions, however, the gravitational backreaction of such a field cannot be consistently solved
A Lie based 4-dimensional higher Chern-Simons theory
Zucchini, Roberto
2016-05-01
We present and study a model of 4-dimensional higher Chern-Simons theory, special Chern-Simons (SCS) theory, instances of which have appeared in the string literature, whose symmetry is encoded in a skeletal semistrict Lie 2-algebra constructed from a compact Lie group with non discrete center. The field content of SCS theory consists of a Lie valued 2-connection coupled to a background closed 3-form. SCS theory enjoys a large gauge and gauge for gauge symmetry organized in an infinite dimensional strict Lie 2-group. The partition function of SCS theory is simply related to that of a topological gauge theory localizing on flat connections with degree 3 second characteristic class determined by the background 3-form. Finally, SCS theory is related to a 3-dimensional special gauge theory whose 2-connection space has a natural symplectic structure with respect to which the 1-gauge transformation action is Hamiltonian, the 2-curvature map acting as moment map.
Higher-Dimensional Solitons Stabilized by Opposite Charge
Binder, B
2002-01-01
In this paper it is shown how higher-dimensional solitons can be stabilized by a topological phase gradient, a field-induced shift in effective dimensionality. As a prototype, two instable 2-dimensional radial symmetric Sine-Gordon extensions (pulsons) are coupled by a sink/source term such, that one becomes a stable 1d and the other a 3d wave equation. The corresponding physical process is identified as a polarization that fits perfectly to preliminary considerations regarding the nature of electric charge and background of 1/137. The coupling is iterative with convergence limit and bifurcation at high charge. It is driven by the topological phase gradient or non-local Gauge potential that can be mapped to a local oscillator potential under PSL(2,R).
Diffusion in higher dimensional SYK model with complex fermions
Cai, Wenhe; Ge, Xian-Hui; Yang, Guo-Hong
2018-01-01
We construct a new higher dimensional SYK model with complex fermions on bipartite lattices. As an extension of the original zero-dimensional SYK model, we focus on the one-dimension case, and similar Hamiltonian can be obtained in higher dimensions. This model has a conserved U(1) fermion number Q and a conjugate chemical potential μ. We evaluate the thermal and charge diffusion constants via large q expansion at low temperature limit. The results show that the diffusivity depends on the ratio of free Majorana fermions to Majorana fermions with SYK interactions. The transport properties and the butterfly velocity are accordingly calculated at low temperature. The specific heat and the thermal conductivity are proportional to the temperature. The electrical resistivity also has a linear temperature dependence term.
Higher-dimensional analogues of Donaldson-Witten theory
International Nuclear Information System (INIS)
Acharya, B.S.; Spence, B.
1997-01-01
We present a Donaldson-Witten-type field theory in eight dimensions on manifolds with Spin(7) holonomy. We prove that the stress tensor is BRST exact for metric variations preserving the holonomy and we give the invariants for this class of variations. In six and seven dimensions we propose similar theories on Calabi-Yau threefolds and manifolds of G 2 holonomy, respectively. We point out that these theories arise by considering supersymmetric Yang-Mills theory defined on such manifolds. The theories are invariant under metric variations preserving the holonomy structure without the need for twisting. This statement is a higher-dimensional analogue of the fact that Donaldson-Witten field theory on hyper-Kaehler 4-manifolds is topological without twisting. Higher-dimensional analogues of Floer cohomology are briefly outlined. All of these theories arise naturally within the context of string theory. (orig.)
The Peierls argument for higher dimensional Ising models
International Nuclear Information System (INIS)
Bonati, Claudio
2014-01-01
The Peierls argument is a mathematically rigorous and intuitive method to show the presence of a non-vanishing spontaneous magnetization in some lattice models. This argument is typically explained for the D = 2 Ising model in a way which cannot be easily generalized to higher dimensions. The aim of this paper is to present an elementary discussion of the Peierls argument for the general D-dimensional Ising model. (paper)
Higher dimensional strange quark matter solutions in self creation cosmology
Energy Technology Data Exchange (ETDEWEB)
Şen, R., E-mail: ramazansen-1991@hotmail.com [Institute for Natural and Applied Sciences, Çanakkale Onsekiz Mart University, 17020, Çanakkale (Turkey); Aygün, S., E-mail: saygun@comu.edu.tr [Department of Physics, Art and Science Faculty, Çanakkale Onsekiz Mart University, Çanakkale 17020 (Turkey)
2016-03-25
In this study, we have generalized the higher dimensional flat Friedmann-Robertson-Walker (FRW) universe solutions for a cloud of string with perfect fluid attached strange quark matter (SQM) in Self Creation Cosmology (SCC). We have obtained that the cloud of string with perfect fluid does not survive and the string tension density vanishes for this model. However, we get dark energy model for strange quark matter with positive density and negative pressure in self creation cosmology.
Torsion and curvature in higher dimensional supergravity theories
International Nuclear Information System (INIS)
Smith, A.W.; Pontificia Univ. Catolica do Rio de Janeiro
1983-01-01
This work is an extension of Dragon's theorems to higher dimensional space-time. It is shown that the first set of Bianchi identities allow us to express the curvature components in terms of torsion components and its covariant derivatives. It is also shown that the second set of Bianchi identities does not give any new information which is not already contained in the first one. (Author) [pt
Bisimulation for Higher-Dimensional Automata. A Geometric Interpretation
DEFF Research Database (Denmark)
Fahrenberg, Ulrich
We show how parallel compostition of higher-dimensional automata (HDA) can be expressed categorically in the spirit of Winskel & Nielsen. Employing the notion of computation path introduced by van Glabbeek, we define a new notion of bisimulation of HDA using open maps. We derive a connection...... between computation paths and carrier sequences of dipaths and show that bisimilarity of HDA can be decided by the use of geometric techniques....
Naked singularities in higher dimensional Vaidya space-times
International Nuclear Information System (INIS)
Ghosh, S. G.; Dadhich, Naresh
2001-01-01
We investigate the end state of the gravitational collapse of a null fluid in higher-dimensional space-times. Both naked singularities and black holes are shown to be developing as the final outcome of the collapse. The naked singularity spectrum in a collapsing Vaidya region (4D) gets covered with the increase in dimensions and hence higher dimensions favor a black hole in comparison to a naked singularity. The cosmic censorship conjecture will be fully respected for a space of infinite dimension
Accretion onto a charged higher-dimensional black hole
International Nuclear Information System (INIS)
Sharif, M.; Iftikhar, Sehrish
2016-01-01
This paper deals with the steady-state polytropic fluid accretion onto a higher-dimensional Reissner-Nordstroem black hole. We formulate the generalized mass flux conservation equation, energy flux conservation and relativistic Bernoulli equation to discuss the accretion process. The critical accretion is investigated by finding the critical radius, the critical sound velocity, and the critical flow velocity. We also explore gas compression and temperature profiles to analyze the asymptotic behavior. It is found that the results for the Schwarzschild black hole are recovered when q = 0 in four dimensions. We conclude that the accretion process in higher dimensions becomes slower in the presence of charge. (orig.)
Accretion onto a charged higher-dimensional black hole
Energy Technology Data Exchange (ETDEWEB)
Sharif, M.; Iftikhar, Sehrish [University of the Punjab, Department of Mathematics, Lahore (Pakistan)
2016-03-15
This paper deals with the steady-state polytropic fluid accretion onto a higher-dimensional Reissner-Nordstroem black hole. We formulate the generalized mass flux conservation equation, energy flux conservation and relativistic Bernoulli equation to discuss the accretion process. The critical accretion is investigated by finding the critical radius, the critical sound velocity, and the critical flow velocity. We also explore gas compression and temperature profiles to analyze the asymptotic behavior. It is found that the results for the Schwarzschild black hole are recovered when q = 0 in four dimensions. We conclude that the accretion process in higher dimensions becomes slower in the presence of charge. (orig.)
Multilinear operators for higher-order decompositions.
Energy Technology Data Exchange (ETDEWEB)
Kolda, Tamara Gibson
2006-04-01
We propose two new multilinear operators for expressing the matrix compositions that are needed in the Tucker and PARAFAC (CANDECOMP) decompositions. The first operator, which we call the Tucker operator, is shorthand for performing an n-mode matrix multiplication for every mode of a given tensor and can be employed to concisely express the Tucker decomposition. The second operator, which we call the Kruskal operator, is shorthand for the sum of the outer-products of the columns of N matrices and allows a divorce from a matricized representation and a very concise expression of the PARAFAC decomposition. We explore the properties of the Tucker and Kruskal operators independently of the related decompositions. Additionally, we provide a review of the matrix and tensor operations that are frequently used in the context of tensor decompositions.
Bianchi's Bäcklund transformation for higher dimensional quadrics
Dincă, Ion I.
2016-12-01
We provide a generalization of Bianchi's Bäcklund transformation from 2-dimensional quadrics to higher dimensional quadrics (which is also a generalization of Tenenblat-Terng's Bäcklund transformation of isometric deformations of Hn(R) in R 2 n - 1 to general quadrics). Our investigation is the higher dimensional version of Bianchi's main three theorems on the theory of isometric deformations of quadrics and Bianchi's treatment of the Bäcklund transformation for diagonal paraboloids via conjugate systems. It became the driving force which led to the flourishing of the classical differential geometry in the second half of the XIX th century and its profound study by illustrious geometers led to interesting results. Today it is still an open problem in its full generality, but basic familiar results like the Gauß-Bonnet fundamental theorem of surfaces and the Codazzi-Mainardi equations (independently discovered also by Peterson) were first communicated to the French Academy of Sciences. A list (most likely incomplete) of the winners of the prize includes Bianchi, Bonnet, Guichard, Weingarten.Up to 1899 isometric deformations of the (pseudo-)sphere and isotropic quadrics without center (from a metric point of view they can be considered as metrically degenerate quadrics without center) together with their Bäcklund transformation and the complementary transformation of isometric deformations of surfaces of revolution were investigated by geometers such as Bäcklund, Bianchi, Bonnet, Darboux, Goursat, Hazzidakis, Lie, Weingarten, etc.In 1899 Guichard discovered that when quadrics with(out) center and of revolution around the focal axis roll on their isometric deformations their foci describe constant mean curvature (minimal) surfaces (and Bianchi proved the converse: all constant mean curvature (minimal) surfaces can be realized in this way).With Guichard's result the race to find the isometric deformations of general quadrics was on; it ended with Bianchi
Operational overhead of moving to higher energies
Lamont, M
2011-01-01
The operational overheads of moving above 3.5 TeV are examined. The costs of performing such a move at the start, or during, the 2011 run are evaluated. The impact of operation with beams above 3.5 TeV on machine protection systems is briefly reviewed, and any potential limitations are enumerated. Finally the possible benefits of increasing the beam energy on the luminosity are discussed.
Possibility of higher-dimensional anisotropic compact star
International Nuclear Information System (INIS)
Bhar, Piyali; Rahaman, Farook; Ray, Saibal; Chatterjee, Vikram
2015-01-01
We provide a new class of interior solutions for anisotropic stars admitting conformal motion in higher-dimensional noncommutative spacetime. The Einstein field equations are solved by choosing a particular density distribution function of Lorentzian type as provided by Nazari and Mehdipour [1, 2] under a noncommutative geometry. Several cases with 4 and higher dimensions, e.g. 5, 6, and 11 dimensions, are discussed separately. An overall observation is that the model parameters, such as density, radial pressure, transverse pressure, and anisotropy, all are well behaved and represent a compact star with mass 2.27 M s un and radius 4.17 km. However, emphasis is put on the acceptability of the model from a physical point of view. As a consequence it is observed that higher dimensions, i.e. beyond 4D spacetime, exhibit several interesting yet bizarre features, which are not at all untenable for a compact stellar model of strange quark type; thus this dictates the possibility of its extra-dimensional existence. (orig.)
Possibility of higher-dimensional anisotropic compact star
Energy Technology Data Exchange (ETDEWEB)
Bhar, Piyali; Rahaman, Farook [Jadavpur University, Department of Mathematics, Kolkata, West Bengal (India); Ray, Saibal [Government College of Engineering and Ceramic Technology, Department of Physics, Kolkata, West Bengal (India); Chatterjee, Vikram [Central Footwear Training Centre, Department of Physics, Parganas, West Bengal (India)
2015-05-15
We provide a new class of interior solutions for anisotropic stars admitting conformal motion in higher-dimensional noncommutative spacetime. The Einstein field equations are solved by choosing a particular density distribution function of Lorentzian type as provided by Nazari and Mehdipour [1, 2] under a noncommutative geometry. Several cases with 4 and higher dimensions, e.g. 5, 6, and 11 dimensions, are discussed separately. An overall observation is that the model parameters, such as density, radial pressure, transverse pressure, and anisotropy, all are well behaved and represent a compact star with mass 2.27 M{sub s}un and radius 4.17 km. However, emphasis is put on the acceptability of the model from a physical point of view. As a consequence it is observed that higher dimensions, i.e. beyond 4D spacetime, exhibit several interesting yet bizarre features, which are not at all untenable for a compact stellar model of strange quark type; thus this dictates the possibility of its extra-dimensional existence. (orig.)
Higher dimensional curved domain walls on Kähler surfaces
Energy Technology Data Exchange (ETDEWEB)
Akbar, Fiki T., E-mail: ftakbar@fi.itb.ac.id [Theoretical Physics Laboratory, Theoretical High Energy Physics and Instrumentation Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha no. 10 Bandung, 40132 (Indonesia); Gunara, Bobby E., E-mail: bobby@fi.itb.ac.id [Theoretical Physics Laboratory, Theoretical High Energy Physics and Instrumentation Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha no. 10 Bandung, 40132 (Indonesia); Radjabaycolle, Flinn C. [Theoretical Physics Laboratory, Theoretical High Energy Physics and Instrumentation Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha no. 10 Bandung, 40132 (Indonesia); Departement of Physics, Faculty of Mathematics and Natural Sciences, Cendrawasih University, Jl. Kampwolker Kampus Uncen Baru Waena-Jayapura 99351 (Indonesia); Wijaya, Rio N. [Theoretical Physics Laboratory, Theoretical High Energy Physics and Instrumentation Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha no. 10 Bandung, 40132 (Indonesia)
2017-03-15
In this paper we study some aspects of curved BPS-like domain walls in higher dimensional gravity theory coupled to scalars where the scalars span a complex Kähler surface with scalar potential turned on. Assuming that a fake superpotential has a special form which depends on Kähler potential and a holomorphic function, we prove that BPS-like equations have a local unique solution. Then, we analyze the vacuum structure of the theory including their stability using dynamical system and their existence in ultraviolet-infrared regions using renormalization group flow.
Ultraviolet divergences in higher dimensional supersymmetric Yang-Mills theories
International Nuclear Information System (INIS)
Howe, P.S.; Stelle, K.S.
1984-01-01
We determine the loop orders for the onset of allowed ultra-violet divergences in higher dimensional supersymmetric Yang-Mills theories. Cancellations are controlled by the non-renormalization theorems for the linearly realizable supersymmetries and by the requirement that counterterms display the full non-linear supersymmetries when the classical equations of motion are imposed. The first allowed divergences in the maximal super Yang-Mills theories occur at four loops in five dimensions, three loops in six dimensions and two loops in seven dimensions. (orig.)
Higher dimensional curved domain walls on Kähler surfaces
International Nuclear Information System (INIS)
Akbar, Fiki T.; Gunara, Bobby E.; Radjabaycolle, Flinn C.; Wijaya, Rio N.
2017-01-01
In this paper we study some aspects of curved BPS-like domain walls in higher dimensional gravity theory coupled to scalars where the scalars span a complex Kähler surface with scalar potential turned on. Assuming that a fake superpotential has a special form which depends on Kähler potential and a holomorphic function, we prove that BPS-like equations have a local unique solution. Then, we analyze the vacuum structure of the theory including their stability using dynamical system and their existence in ultraviolet-infrared regions using renormalization group flow.
Charged particle in higher dimensional weakly charged rotating black hole spacetime
International Nuclear Information System (INIS)
Frolov, Valeri P.; Krtous, Pavel
2011-01-01
We study charged particle motion in weakly charged higher dimensional black holes. To describe the electromagnetic field we use a test field approximation and the higher dimensional Kerr-NUT-(A)dS metric as a background geometry. It is shown that for a special configuration of the electromagnetic field, the equations of motion of charged particles are completely integrable. The vector potential of such a field is proportional to one of the Killing vectors (called a primary Killing vector) from the 'Killing tower' of symmetry generating objects which exists in the background geometry. A free constant in the definition of the adopted electromagnetic potential is proportional to the electric charge of the higher dimensional black hole. The full set of independent conserved quantities in involution is found. We demonstrate that Hamilton-Jacobi equations are separable, as is the corresponding Klein-Gordon equation and its symmetry operators.
Stationary strings near a higher-dimensional rotating black hole
International Nuclear Information System (INIS)
Frolov, Valeri P.; Stevens, Kory A.
2004-01-01
We study stationary string configurations in a space-time of a higher-dimensional rotating black hole. We demonstrate that the Nambu-Goto equations for a stationary string in the 5D (five-dimensional) Myers-Perry metric allow a separation of variables. We present these equations in the first-order form and study their properties. We prove that the only stationary string configuration that crosses the infinite redshift surface and remains regular there is a principal Killing string. A worldsheet of such a string is generated by a principal null geodesic and a timelike at infinity Killing vector field. We obtain principal Killing string solutions in the Myers-Perry metrics with an arbitrary number of dimensions. It is shown that due to the interaction of a string with a rotating black hole, there is an angular momentum transfer from the black hole to the string. We calculate the rate of this transfer in a space-time with an arbitrary number of dimensions. This effect slows down the rotation of the black hole. We discuss possible final stationary configurations of a rotating black hole interacting with a string
Geometry of higher-dimensional black hole thermodynamics
International Nuclear Information System (INIS)
Aaman, Jan E.; Pidokrajt, Narit
2006-01-01
We investigate thermodynamic curvatures of the Kerr and Reissner-Nordstroem (RN) black holes in spacetime dimensions higher than four. These black holes possess thermodynamic geometries similar to those in four-dimensional spacetime. The thermodynamic geometries are the Ruppeiner geometry and the conformally related Weinhold geometry. The Ruppeiner geometry for a d=5 Kerr black hole is curved and divergent in the extremal limit. For a d≥6 Kerr black hole there is no extremality but the Ruppeiner curvature diverges where one suspects that the black hole becomes unstable. The Weinhold geometry of the Kerr black hole in arbitrary dimension is a flat geometry. For the RN black hole the Ruppeiner geometry is flat in all spacetime dimensions, whereas its Weinhold geometry is curved. In d≥5 the Kerr black hole can possess more than one angular momentum. Finally we discuss the Ruppeiner geometry for the Kerr black hole in d=5 with double angular momenta
The Phase Transition of Higher Dimensional Charged Black Holes
International Nuclear Information System (INIS)
Li, Huaifan; Zhao, Ren; Zhang, Lichun; Guo, Xiongying
2016-01-01
We have studied phase transitions of higher dimensional charge black hole with spherical symmetry. We calculated the local energy and local temperature and find that these state parameters satisfy the first law of thermodynamics. We analyze the critical behavior of black hole thermodynamic system by taking state parameters (Q,Φ) of black hole thermodynamic system, in accordance with considering the state parameters (P,V) of van der Waals system, respectively. We obtain the critical point of black hole thermodynamic system and find that the critical point is independent of the dual independent variables we selected. This result for asymptotically flat space is consistent with that for AdS spacetime and is intrinsic property of black hole thermodynamic system.
Graviton emission from a higher-dimensional black hole
International Nuclear Information System (INIS)
Cornell, Alan S.; Naylor, Wade; Sasaki, Misao
2006-01-01
We discuss the graviton absorption probability (greybody factor) and the cross-section of a higher-dimensional Schwarzschild black hole (BH). We are motivated by the suggestion that a great many BHs may be produced at the LHC and bearing this fact in mind, for simplicity, we shall investigate the intermediate energy regime for a static Schwarzschild BH. That is, for (2M) 1/(n-1) ω ∼ 1, where M is the mass of the black hole and ω is the energy of the emitted gravitons in (2+n)-dimensions. To find easily tractable solutions we work in the limit l >> 1, where l is the angular momentum quantum number of the graviton
The dynamical structure of higher dimensional Chern-Simons theory
International Nuclear Information System (INIS)
Banados, M.; Garay, L.J.; Henneaux, M.
1996-01-01
Higher dimensional Chern-Simons theories, even though constructed along the same topological pattern as in 2+1 dimensions, have been shown recently to have generically a non-vanishing number of degrees of freedom. In this paper, we carry out the complete Dirac Hamiltonian analysis (separation of first and second class constraints and calculation of the Dirac bracket) for a group G x U(1). We also study the algebra of surface charges that arise in the presence of boundaries and show that it is isomorphic to the WZW 4 discussed in the literature. Some applications are then considered. It is shown, in particular, that Chern-Simons gravity in dimensions greater than or equal to five has a propagating torsion. (orig.)
Dimensional Scaling for Optimized CMUT Operations
DEFF Research Database (Denmark)
Lei, Anders; Diederichsen, Søren Elmin; la Cour, Mette Funding
2014-01-01
This work presents a dimensional scaling study using numerical simulations, where gap height and plate thickness of a CMUT cell is varied, while the lateral plate dimension is adjusted to maintain a constant transmit immersion center frequency of 5 MHz. Two cell configurations have been simulated...
The Higgs particle and higher-dimensional theories
International Nuclear Information System (INIS)
Lim, C. S.
2014-01-01
In spite of the great success of LHC experiments, we do not know whether the discovered “standard model-like” Higgs particle is really what the standard model predicts, or a particle that some new physics has in its low-energy effective theory. Also, the long-standing problems concerning the property of the Higgs and its interactions are still there, and we still do not have any conclusive argument on the origin of the Higgs itself. In this article we focus on higher-dimensional theories as new physics. First we give a brief review of their representative scenarios and closely related 4D scenarios. Among them, we mainly discuss two interesting possibilities of the origin of the Higgs: the Higgs as a gauge boson and the Higgs as a (pseudo) Nambu–Goldstone boson. Next, we argue that theories of new physics are divided into two categories, i.e., theories with normal Higgs interactions and those with anomalous Higgs interactions. Interestingly, both the candidates for the origin of the Higgs mentioned above predict characteristic “anomalous” Higgs interactions, such as the deviation of the Yukawa couplings from the standard model predictions. Such deviations can hopefully be investigated by precision tests of Higgs interactions at the planned ILC experiment. Also discussed is the main decay mode of the Higgs, H→γγ. Again, theories belonging to different categories are known to predict remarkably different new physics contributions to this important process
Massive Higher Dimensional Gauge Fields as Messengers of Supersymmetry Breaking
International Nuclear Information System (INIS)
Chacko, Z.; Luty, Markus A.; Ponton, Eduardo
2000-01-01
We consider theories with one or more compact dimensions with size r > 1/M, where M is the fundamental Planck scale, with the visible and hidden sectors localized on spatially separated 3 -branes''. We show that a bulk U(1) gauge field spontaneously broken on the hidden-sector 3-brane is an attractive candidate for the messenger of supersymmetry breaking. In this scenario scalar mass-squared terms are proportional to U(1) charges, and therefore naturally conserve flavor. Arbitrary flavor violation at the Planck scale gives rise to exponentially suppressed flavor violation at low energies. Gaugino masses can be generated if the standard gauge fields propagate in the bulk; μ and Bμ terms can be generated by the Giudice-Masiero or by the VEV of a singlet in the visible sector. The latter case naturally solves the SUSY CP problem. Realistic phenomenology can be obtained either if all microscopic parameters are order one in units of M, or if the theory is strongly coupled at the scale M. (For the latter case, we estimate parameters by extending n aive dimensional analysis'' to higher-dimension theories with branes.) In either case, the only unexplained hierarchy is the l arge'' size of the extra dimensions in fundamental units, which need only be an order of magnitude. All soft masses are naturally within an order of magnitude of m 3/2 , and trilinear scalar couplings are negligible. Squark and slepton masses can naturally unify even in the absence of grand unification. (author)
Spinning higher dimensional Einstein-Yang-Mills black holes
International Nuclear Information System (INIS)
Ghosh, Sushant G.; Papnoi, Uma
2014-01-01
We construct a Kerr-Newman-like spacetime starting from higher dimensional (HD) Einstein-Yang-Mills black holes via complex transformations suggested by Newman-Janis. The new metrics are a HD generalization of Kerr-Newman spacetimes which has a geometry that is precisely that of Kerr-Newman in 4D corresponding to a Yang-Mills (YM) gauge charge, but the sign of the charge term gets flipped in the HD spacetimes. It is interesting to note that the gravitational contribution of the YM gauge charge, in HD, is indeed opposite (attractive rather than repulsive) to that of the Maxwell charge. The effect of the YM gauge charge on the structure and location of static limit surface and apparent horizon is discussed. We find that static limit surfaces become less prolate with increase in dimensions and are also sensitive to the YM gauge charge, thereby affecting the shape of the ergosphere. We also analyze some thermodynamical properties of these BHs. (orig.)
Spinning higher dimensional Einstein-Yang-Mills black holes
Energy Technology Data Exchange (ETDEWEB)
Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of Kwa-Zulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, Private Bag 54001, Durban (South Africa); Papnoi, Uma [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India)
2014-08-15
We construct a Kerr-Newman-like spacetime starting from higher dimensional (HD) Einstein-Yang-Mills black holes via complex transformations suggested by Newman-Janis. The new metrics are a HD generalization of Kerr-Newman spacetimes which has a geometry that is precisely that of Kerr-Newman in 4D corresponding to a Yang-Mills (YM) gauge charge, but the sign of the charge term gets flipped in the HD spacetimes. It is interesting to note that the gravitational contribution of the YM gauge charge, in HD, is indeed opposite (attractive rather than repulsive) to that of the Maxwell charge. The effect of the YM gauge charge on the structure and location of static limit surface and apparent horizon is discussed. We find that static limit surfaces become less prolate with increase in dimensions and are also sensitive to the YM gauge charge, thereby affecting the shape of the ergosphere. We also analyze some thermodynamical properties of these BHs. (orig.)
An approach to higher dimensional theories based on lattice gauge theory
International Nuclear Information System (INIS)
Murata, M.; So, H.
2004-01-01
A higher dimensional lattice space can be decomposed into a number of four-dimensional lattices called as layers. The higher dimensional gauge theory on the lattice can be interpreted as four-dimensional gauge theories on the multi-layer with interactions between neighboring layers. We propose the new possibility to realize the continuum limit of a five-dimensional theory based on the property of the phase diagram
Euclidean D-branes and higher-dimensional gauge theory
International Nuclear Information System (INIS)
Acharya, B.S.; Figueroa-O'Farrill, J.M.; Spence, B.; O'Loughlin, M.
1997-07-01
We consider euclidean D-branes wrapping around manifolds of exceptional holonomy in dimensions seven and eight. The resulting theory on the D-brane-that is, the dimensional reduction of 10-dimensional supersymmetric Yang-Mills theory-is a cohomological field theory which describes the topology of the moduli space of instantons. The 7-dimensional theory is an N T =2 (or balanced) cohomological theory given by an action potential of Chern-Simons type. As a by-product of this method, we construct a related cohomological field theory which describes the monopole moduli space on a 7-manifold of G 2 holonomy. (author). 22 refs, 3 tabs
Faster Black-Box Algorithms Through Higher Arity Operators
DEFF Research Database (Denmark)
Doerr, Benjamin; Johannsen, Daniel; Kötzing, Timo
2011-01-01
We extend the work of Lehre and Witt (GECCO 2010) on the unbiased black-box model by considering higher arity variation operators. In particular, we show that already for binary operators the black-box complexity of LeadingOnes drops from (n2) for unary operators to O(n log n). For OneMax, the (n...
Higher-dimensional cosmological model with variable gravitational ...
Indian Academy of Sciences (India)
We have studied five-dimensional homogeneous cosmological models with variable and bulk viscosity in Lyra geometry. Exact solutions for the field equations have been obtained and physical properties of the models are discussed. It has been observed that the results of new models are well within the observational ...
Application of Quantum Process Calculus to Higher Dimensional Quantum Protocols
Directory of Open Access Journals (Sweden)
Simon J. Gay
2014-07-01
Full Text Available We describe the use of quantum process calculus to describe and analyze quantum communication protocols, following the successful field of formal methods from classical computer science. We have extended the quantum process calculus to describe d-dimensional quantum systems, which has not been done before. We summarise the necessary theory in the generalisation of quantum gates and Bell states and use the theory to apply the quantum process calculus CQP to quantum protocols, namely qudit teleportation and superdense coding.
Instability of higher dimensional Yang-Mills systems
International Nuclear Information System (INIS)
Randjbar-Daemi, S.; Strathdee, J.
1983-01-01
We investigate the stability of Poincare xO(3) invariant solutions for a pure semi-simple Yang-Mills, as well as Yang-Mills coupled to gravity in 6-dimensional space-time compactified over M 4 xS 2 . In contrast to the Maxwell U(1) theory (IC-82/208) in six dimensions coupled with gravity and investigated previously, the present theory exhibits tachyonic excitations and is unstable. (author)
A toy model for higher spin Dirac operators
International Nuclear Information System (INIS)
Eelbode, D.; Van de Voorde, L.
2010-01-01
This paper deals with the higher spin Dirac operator Q 2,1 acting on functions taking values in an irreducible representation space for so(m) with highest weight (5/2, 3/2, 1/2,..., 1/2). . This operator acts as a toy model for generalizations of the classical Rarita-Schwinger equations in Clifford analysis. Polynomial null solutions for this operator are studied in particular.
Control Operator for the Two-Dimensional Energized Wave Equation
Directory of Open Access Journals (Sweden)
Sunday Augustus REJU
2006-07-01
Full Text Available This paper studies the analytical model for the construction of the two-dimensional Energized wave equation. The control operator is given in term of space and time t independent variables. The integral quadratic objective cost functional is subject to the constraint of two-dimensional Energized diffusion, Heat and a source. The operator that shall be obtained extends the Conjugate Gradient method (ECGM as developed by Hestenes et al (1952, [1]. The new operator enables the computation of the penalty cost, optimal controls and state trajectories of the two-dimensional energized wave equation when apply to the Conjugate Gradient methods in (Waziri & Reju, LEJPT & LJS, Issues 9, 2006, [2-4] to appear in this series.
Dai, Jian; Song, Xing-Chang
2001-07-01
One of the key ingredients of Connes's noncommutative geometry is a generalized Dirac operator which induces a metric (Connes's distance) on the pure state space. We generalize such a Dirac operator devised by Dimakis et al, whose Connes distance recovers the linear distance on an one-dimensional lattice, to the two-dimensional case. This Dirac operator has the local eigenvalue property and induces a Euclidean distance on this two-dimensional lattice, which is referred to as `natural'. This kind of Dirac operator can be easily generalized into any higher-dimensional lattices.
Extended higher-spin superalgebras and their realizations in terms of quantum operators
Energy Technology Data Exchange (ETDEWEB)
Vasiliev, M A
1988-01-01
The realization of the N = 1 higher-spin superalgebra, proposed earlier by E.S. Fradkin and the author, is found in terms of bosonic quantum operators. The extended higher-spin superalgebras, generalizing ordinary extended supersymmetry with arbitrary N > 1, are constructed by adding fermion quantum operators. Automorphisms, real forms, subalgebras, contractions and invariant forms of these infinite-dimensional superalgebras are studied. The formulation of the higher-spin superalgebras is described in terms of symbols of operators by Berezin. We hope that this formulation will provide in future the powerful tool for constructing the complete solution of the higher-spin problem, the problem of introducing a consistent gravitational interaction for massless higher-spin fields (s > 2).
Unitarity in three-dimensional flat space higher spin theories
International Nuclear Information System (INIS)
Grumiller, D.; Riegler, M.; Rosseel, J.
2014-01-01
We investigate generic flat-space higher spin theories in three dimensions and find a no-go result, given certain assumptions that we spell out. Namely, it is only possible to have at most two out of the following three properties: unitarity, flat space, non-trivial higher spin states. Interestingly, unitarity provides an (algebra-dependent) upper bound on the central charge, like c=42 for the Galilean W_4"("2"−"1"−"1") algebra. We extend this no-go result to rule out unitary “multi-graviton” theories in flat space. We also provide an example circumventing the no-go result: Vasiliev-type flat space higher spin theory based on hs(1) can be unitary and simultaneously allow for non-trivial higher-spin states in the dual field theory.
The Fuzzy analogy of chiral diffeomorphisms in higher dimensional quantum field theories
International Nuclear Information System (INIS)
Fassarella, Lucio; Schroer, Bert
2001-06-01
Our observation that the chiral diffeomorphisms allow an interpretation as modular groups of local operator algebras in the sense of Tomita and takesaki allows us to conclude that the higher deimensional generalizations are certain infinite dimensional groups which act in a 'fuzzy' way on the operator algebras of local quantum physics. These actions do not require any spacetime noncommutativity and are in complete harmony with causality and localization principles. The use of an appropriately defined isomorphism reprocesses these fuzzy actions into partially geometric actions on the holographic image and in this way tightens the relation with chiral structures and makes recent attempts to explain the required universal structure of a would be quantum Bekenstein law in terms of Virasoro algebra structures more palatable. (author)
Linear waves on higher dimensional Schwarzschild black holes and Schwarzschild de Sitter spacetimes
Schlue, Volker
2012-01-01
I study linear waves on higher dimensional Schwarzschild black holes and Schwarzschild de Sitter spacetimes. In the first part of this thesis two decay results are proven for general finite energy solutions to the linear wave equation on higher dimensional Schwarzschild black holes. I establish uniform energy decay and improved interior first order energy decay in all dimensions with rates in accordance with the 3 + 1-dimensional case. The method of proof departs from earlier work on th...
Conductivity of higher dimensional holographic superconductors with nonlinear electrodynamics
Sheykhi, Ahmad; Hashemi Asl, Doa; Dehyadegari, Amin
2018-06-01
We investigate analytically as well as numerically the properties of s-wave holographic superconductors in d-dimensional spacetime and in the presence of Logarithmic nonlinear electrodynamics. We study three aspects of this kind of superconductors. First, we obtain, by employing analytical Sturm-Liouville method as well as numerical shooting method, the relation between critical temperature and charge density, ρ, and disclose the effects of both nonlinear parameter b and the dimensions of spacetime, d, on the critical temperature Tc. We find that in each dimension, Tc /ρ 1 / (d - 2) decreases with increasing the nonlinear parameter b while it increases with increasing the dimension of spacetime for a fixed value of b. Then, we calculate the condensation value and critical exponent of the system analytically and numerically and observe that in each dimension, the dimensionless condensation get larger with increasing the nonlinear parameter b. Besides, for a fixed value of b, it increases with increasing the spacetime dimension. We confirm that the results obtained from our analytical method are in agreement with the results obtained from numerical shooting method. This fact further supports the correctness of our analytical method. Finally, we explore the holographic conductivity of this system and find out that the superconducting gap increases with increasing either the nonlinear parameter or the spacetime dimension.
Gravitational collapse in higher-dimensional charged-Vaidya space ...
Indian Academy of Sciences (India)
time. We show that singularities arising in a charged null fluid in higher dimension are always naked violating ... of matter is one of the most active field of research in the contemporary general relativity. ... The main open issue ..... [3] A Papapetrou, in A random walk in relativity and cosmology edited by N Dadhich, J K Rao,.
Finite-dimensional approximation for operator equations of Hammerstein type
International Nuclear Information System (INIS)
Buong, N.
1992-11-01
The purpose of this paper is to establish convergence rate for a method of finite-dimensional approximation to solve operator equation of Hammerstein type in real reflexive Banach space. In order to consider a numerical example an iteration method is proposed in Hilbert space. (author). 25 refs
Small Aircraft Transportation System Higher Volume Operations Concept
Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Jones, Kenneth M.; Adams, Catherine A.
2006-01-01
This document defines the Small Aircraft Transportation System (SATS) Higher Volume Operations concept. The general philosophy underlying this concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. This document also provides details for a number of off-nominal and emergency procedures which address situations that could be expected to occur in a future SCA. The details for this operational concept along with a description of candidate aircraft systems to support this concept are provided.
Casimir energy and the possibility of higher dimensional manipulation
Obousy, R. K.; Saharian, A. A.
2009-01-01
It is well known that the Casimir effect is an excellent candidate for the stabilization of the extra dimensions. It has also been suggested that the Casimir effect in higher dimensions may be the underlying phenomenon that is responsible for the dark energy which is currently driving the accelerated expansion of the universe. In this paper we suggest that, in principle, it may be possible to directly manipulate the size of an extra dimension locally using Standard Model fields in the next ge...
Higher-dimensional bosonization and its application to Fermi liquids
Energy Technology Data Exchange (ETDEWEB)
Meier, Hendrik
2012-06-28
The bosonization scheme presented in this thesis allows to map models of interacting fermions onto equivalent models describing collective bosonic excitations. For simple systems that do not require plenty computational power and optimized algorithms, the positivity of the weight function in the bosonic frame has been confirmed - in particular also for those configurations in which the fermionic representation shows the minus-sign problem. The numerical tests are absolutely elementary and based on the simplest possible regularization scheme. The second part of this thesis presented an analytical study about the non-analytic corrections to thermodynamic quantities in a two-dimensional Fermi liquid. The perturbation theory developed for the exact formulation is by no means more convenient than the well-established fermionic diagram technique. The effective low-energy theory for studying the anomalous contributions to the Fermi liquid was derived focussing on the relevant soft modes of the interaction only. The final effective model took the form of a field theory for a bosonic superfield Ψ interacting in quadratic, cubic, and quartic terms in the action. This field theory turned out nontrivial and was shown to lead to logarithmic divergencies in both spin and charge channels. By means of a combined scheme of ladder diagram summations and renormalization group equations, the logarithmic terms were summed up in the first-loop order, thus yielding the renormalized effective coupling constants of the theory at low temperatures. The fully renormalized action then allowed to conveniently compute the low-temperature limit behavior of the non-analytic corrections to the Fermi-liquid thermodynamic response functions such as the low temperature non-analytic correction δc to the specific heat. The explicit formula for δc is the sum of two contributions - one due to the spin singlet and one due to the spin triplet superconducting excitations. Depending on the values of the
Formulation of Higher Education Institutional Strategy Using Operational Research Approaches
Labib, Ashraf; Read, Martin; Gladstone-Millar, Charlotte; Tonge, Richard; Smith, David
2014-01-01
In this paper a framework is proposed for the formulation of a higher education institutional (HEI) strategy. This work provides a practical example, through a case study, to demonstrate how the proposed framework can be applied to the issue of formulation of HEI strategy. The proposed hybrid model is based on two operational research…
Static wormhole solution for higher-dimensional gravity in vacuum
International Nuclear Information System (INIS)
Dotti, Gustavo; Oliva, Julio; Troncoso, Ricardo
2007-01-01
A static wormhole solution for gravity in vacuum is found for odd dimensions greater than four. In five dimensions the gravitational theory considered is described by the Einstein-Gauss-Bonnet action where the coupling of the quadratic term is fixed in terms of the cosmological constant. In higher dimensions d=2n+1, the theory corresponds to a particular case of the Lovelock action containing higher powers of the curvature, so that in general, it can be written as a Chern-Simons form for the AdS group. The wormhole connects two asymptotically locally AdS spacetimes each with a geometry at the boundary locally given by RxS 1 xH d-3 . Gravity pulls towards a fixed hypersurface located at some arbitrary proper distance parallel to the neck. The causal structure shows that both asymptotic regions are connected by light signals in a finite time. The Euclidean continuation of the wormhole is smooth independently of the Euclidean time period, and it can be seen as instanton with vanishing Euclidean action. The mass can also be obtained from a surface integral and it is shown to vanish
Identifying Talent in Youth Sport: A Novel Methodology Using Higher-Dimensional Analysis
Till, Kevin; Jones, Ben L.; Cobley, Stephen; Morley, David; O'Hara, John; Chapman, Chris; Cooke, Carlton; Beggs, Clive B.
2016-01-01
Prediction of adult performance from early age talent identification in sport remains difficult. Talent identification research has generally been performed using univariate analysis, which ignores multivariate relationships. To address this issue, this study used a novel higher-dimensional model to orthogonalize multivariate anthropometric and fitness data from junior rugby league players, with the aim of differentiating future career attainment. Anthropometric and fitness data from 257 Under-15 rugby league players was collected. Players were grouped retrospectively according to their future career attainment (i.e., amateur, academy, professional). Players were blindly and randomly divided into an exploratory (n = 165) and validation dataset (n = 92). The exploratory dataset was used to develop and optimize a novel higher-dimensional model, which combined singular value decomposition (SVD) with receiver operating characteristic analysis. Once optimized, the model was tested using the validation dataset. SVD analysis revealed 60 m sprint and agility 505 performance were the most influential characteristics in distinguishing future professional players from amateur and academy players. The exploratory dataset model was able to distinguish between future amateur and professional players with a high degree of accuracy (sensitivity = 85.7%, specificity = 71.1%; ptalent identification. PMID:27224653
Identifying Talent in Youth Sport: A Novel Methodology Using Higher-Dimensional Analysis.
Till, Kevin; Jones, Ben L; Cobley, Stephen; Morley, David; O'Hara, John; Chapman, Chris; Cooke, Carlton; Beggs, Clive B
2016-01-01
Prediction of adult performance from early age talent identification in sport remains difficult. Talent identification research has generally been performed using univariate analysis, which ignores multivariate relationships. To address this issue, this study used a novel higher-dimensional model to orthogonalize multivariate anthropometric and fitness data from junior rugby league players, with the aim of differentiating future career attainment. Anthropometric and fitness data from 257 Under-15 rugby league players was collected. Players were grouped retrospectively according to their future career attainment (i.e., amateur, academy, professional). Players were blindly and randomly divided into an exploratory (n = 165) and validation dataset (n = 92). The exploratory dataset was used to develop and optimize a novel higher-dimensional model, which combined singular value decomposition (SVD) with receiver operating characteristic analysis. Once optimized, the model was tested using the validation dataset. SVD analysis revealed 60 m sprint and agility 505 performance were the most influential characteristics in distinguishing future professional players from amateur and academy players. The exploratory dataset model was able to distinguish between future amateur and professional players with a high degree of accuracy (sensitivity = 85.7%, specificity = 71.1%; ptalent identification.
Directory of Open Access Journals (Sweden)
Liu Yang
2007-10-01
Full Text Available By using coincidence degree theory of Mawhin, existence results for some higher order resonance multipoint boundary value problems with one dimensional p-Laplacian operator are obtained.
International Nuclear Information System (INIS)
Anderson, Gregory W.; Blazek, Tomas
2005-01-01
E 6 is an attractive group for unification model building. However, the complexity of a rank 6 group makes it nontrivial to write down the structure of higher dimensional operators in an E 6 theory in terms of the states labeled by quantum numbers of the standard model gauge group. In this paper, we show the results of our computation of the Clebsch-Gordan coefficients for the products of the 27 with irreducible representations of higher dimensionality: 78, 351, 351 ' , 351, and 351 ' . Application of these results to E 6 model building involving higher dimensional operators is straightforward
Magnetized black holes and black rings in the higher dimensional dilaton gravity
International Nuclear Information System (INIS)
Yazadjiev, Stoytcho S.
2006-01-01
In this paper we consider magnetized black holes and black rings in the higher dimensional dilaton gravity. Our study is based on exact solutions generated by applying a Harrison transformation to known asymptotically flat black hole and black ring solutions in higher dimensional spacetimes. The explicit solutions include the magnetized version of the higher dimensional Schwarzschild-Tangherlini black holes, Myers-Perry black holes, and five-dimensional (dipole) black rings. The basic physical quantities of the magnetized objects are calculated. We also discuss some properties of the solutions and their thermodynamics. The ultrarelativistic limits of the magnetized solutions are briefly discussed and an explicit example is given for the D-dimensional magnetized Schwarzschild-Tangherlini black holes
Euclidean scalar Green function in a higher dimensional global monopole space-time
International Nuclear Information System (INIS)
Bezerra de Mello, E.R.
2002-01-01
We construct the explicit Euclidean scalar Green function associated with a massless field in a higher dimensional global monopole space-time, i.e., a (1+d)-space-time with d≥3 which presents a solid angle deficit. Our result is expressed in terms of an infinite sum of products of Legendre functions with Gegenbauer polynomials. Although this Green function cannot be expressed in a closed form, for the specific case where the solid angle deficit is very small, it is possible to develop the sum and obtain the Green function in a more workable expression. Having this expression it is possible to calculate the vacuum expectation value of some relevant operators. As an application of this formalism, we calculate the renormalized vacuum expectation value of the square of the scalar field, 2 (x)> Ren , and the energy-momentum tensor, μν (x)> Ren , for the global monopole space-time with spatial dimensions d=4 and d=5
On the dimensional reduction of a gravitational theory containing higher-derivative terms
International Nuclear Information System (INIS)
Pollock, M.D.
1990-02-01
From the higher-dimensional gravitational theory L-circumflex=R-circumflex-2Λ-circumflex-α-circumflex 1 R-circumflex 2 =α-circumflex 2 R-circumflex AB R-circumflex AB -α-circumflex 3 R-circumflex ABCD R-circumflex ABCD , we derive the effective four-dimensional Lagrangian L. (author). 12 refs
Manifold learning to interpret JET high-dimensional operational space
International Nuclear Information System (INIS)
Cannas, B; Fanni, A; Pau, A; Sias, G; Murari, A
2013-01-01
In this paper, the problem of visualization and exploration of JET high-dimensional operational space is considered. The data come from plasma discharges selected from JET campaigns from C15 (year 2005) up to C27 (year 2009). The aim is to learn the possible manifold structure embedded in the data and to create some representations of the plasma parameters on low-dimensional maps, which are understandable and which preserve the essential properties owned by the original data. A crucial issue for the design of such mappings is the quality of the dataset. This paper reports the details of the criteria used to properly select suitable signals downloaded from JET databases in order to obtain a dataset of reliable observations. Moreover, a statistical analysis is performed to recognize the presence of outliers. Finally data reduction, based on clustering methods, is performed to select a limited and representative number of samples for the operational space mapping. The high-dimensional operational space of JET is mapped using a widely used manifold learning method, the self-organizing maps. The results are compared with other data visualization methods. The obtained maps can be used to identify characteristic regions of the plasma scenario, allowing to discriminate between regions with high risk of disruption and those with low risk of disruption. (paper)
A higher dimensional explanation of the excess of Higgs-like events at CERN LEP
Van der Bij, J J
2006-01-01
Searches for the SM Higgs boson by the four LEP experiments have found a 2.3 sigma excess at 98 GeV and a smaller 1.7 sigma at around 115 GeV. We interpret these excesses as evidence for a Higgs boson coupled to a higher dimensional singlet scalar. The fit implies a relatively low dimensional mixing scale mu_{lhd} 100 GeV. The data show a slight preference for a five-dimensional over a six-dimensional field. This Higgs boson cannot be seen at the LHC, but can be studied at the ILC.
CSIR Research Space (South Africa)
Mafu, M
2013-09-01
Full Text Available We present an experimental study of higher-dimensional quantum key distribution protocols based on mutually unbiased bases, implemented by means of photons carrying orbital angular momentum. We perform (d + 1) mutually unbiased measurements in a...
Identifying Talent in Youth Sport: A Novel Methodology Using Higher-Dimensional Analysis.
Directory of Open Access Journals (Sweden)
Kevin Till
Full Text Available Prediction of adult performance from early age talent identification in sport remains difficult. Talent identification research has generally been performed using univariate analysis, which ignores multivariate relationships. To address this issue, this study used a novel higher-dimensional model to orthogonalize multivariate anthropometric and fitness data from junior rugby league players, with the aim of differentiating future career attainment. Anthropometric and fitness data from 257 Under-15 rugby league players was collected. Players were grouped retrospectively according to their future career attainment (i.e., amateur, academy, professional. Players were blindly and randomly divided into an exploratory (n = 165 and validation dataset (n = 92. The exploratory dataset was used to develop and optimize a novel higher-dimensional model, which combined singular value decomposition (SVD with receiver operating characteristic analysis. Once optimized, the model was tested using the validation dataset. SVD analysis revealed 60 m sprint and agility 505 performance were the most influential characteristics in distinguishing future professional players from amateur and academy players. The exploratory dataset model was able to distinguish between future amateur and professional players with a high degree of accuracy (sensitivity = 85.7%, specificity = 71.1%; p<0.001, although it could not distinguish between future professional and academy players. The validation dataset model was able to distinguish future professionals from the rest with reasonable accuracy (sensitivity = 83.3%, specificity = 63.8%; p = 0.003. Through the use of SVD analysis it was possible to objectively identify criteria to distinguish future career attainment with a sensitivity over 80% using anthropometric and fitness data alone. As such, this suggests that SVD analysis may be a useful analysis tool for research and practice within talent identification.
Extension of TFTR operations to higher toroidal field levels
International Nuclear Information System (INIS)
Woolley, R.D.
1995-01-01
For the past year, TFTR has sometimes operated at extended toroidal field (TF) levels. The extension to 5.6 Tesla (79 kA) was crucial for TFTR's November 1994 10.7 MW DT fusion power record. The extension to 6.0 Tesla (85 kA) was commissioned on 9 September 1995. There are several reasons that one could expect the TF coils to survive the higher stresses that develop at higher fields. They were designed to operate at 5.2 Tesla with a vertical field of 0.5 Tesla, whereas the actual vertical field needed for the plasma does not exceed 0.35 Tesla. Their design specification explicitly required they survive some pulses at 6.0 Tesla. TF coil mechanical analysis computer models available during coil design were crude, leading to conservative design. And design analyses also had to consider worst-case misoperations that TFTR's real time Coil Protection Calculators (CPCs) now positively prevent from occurring
Unlabored system motion by specially conditioned electromagnetic fields in higher dimensional realms
David Froning, H.; Meholic, Gregory V.
2010-01-01
This third of three papers explores the possibility of swift, stress-less system transitions between slower-than-light and faster-than-light speeds with negligible net expenditure of system energetics. The previous papers derived a realm of higher dimensionality than 4-D spacetime that enabled such unlabored motion; and showed that fields that could propel and guide systems on unlabored paths in the higher dimensional realm must be fields that have been conditioned to SU(2) (or higher) Lie group symmetry. This paper shows that the system's surrounding vacuum dielectric ɛμ, within the higher dimensional realm's is a vector (not scalar) quantity with fixed magnitude ɛ0μ0 and changing direction within the realm with changing system speed. Thus, ɛμ generated by the system's EM field must remain tuned to vacuum ɛ0μ0 in both magnitude and direction during swift, unlabored system transitions between slower and faster than light speeds. As a result, the system's changing path and speed is such that the magnitude of the higher dimensional realm's ɛ0μ0 is not disturbed. And it is shown that a system's flight trajectories associated with its swift, unlabored transitions between zero and infinite speed can be represented by curved paths traced-out within the higher dimensional realm.
The applications of a higher-dimensional Lie algebra and its decomposed subalgebras
Yu, Zhang; Zhang, Yufeng
2009-01-01
With the help of invertible linear transformations and the known Lie algebras, a higher-dimensional 6 × 6 matrix Lie algebra sμ(6) is constructed. It follows a type of new loop algebra is presented. By using a (2 + 1)-dimensional partial-differential equation hierarchy we obtain the integrable coupling of the (2 + 1)-dimensional KN integrable hierarchy, then its corresponding Hamiltonian structure is worked out by employing the quadratic-form identity. Furthermore, a higher-dimensional Lie algebra denoted by E, is given by decomposing the Lie algebra sμ(6), then a discrete lattice integrable coupling system is produced. A remarkable feature of the Lie algebras sμ(6) and E is used to directly construct integrable couplings. PMID:20084092
The applications of a higher-dimensional Lie algebra and its decomposed subalgebras
International Nuclear Information System (INIS)
Yu Zhang; Zhang Yufeng
2009-01-01
With the help of invertible linear transformations and the known Lie algebras, a higher-dimensional 6 x 6 matrix Lie algebra sμ(6) is constructed. It follows a type of new loop algebra is presented. By using a (2 + 1)-dimensional partial-differential equation hierarchy we obtain the integrable coupling of the (2 + 1)-dimensional KN integrable hierarchy, then its corresponding Hamiltonian structure is worked out by employing the quadratic-form identity. Furthermore, a higher-dimensional Lie algebra denoted by E, is given by decomposing the Lie algebra sμ(6), then a discrete lattice integrable coupling system is produced. A remarkable feature of the Lie algebras sμ(6) and E is used to directly construct integrable couplings
The applications of a higher-dimensional Lie algebra and its decomposed subalgebras.
Yu, Zhang; Zhang, Yufeng
2009-01-15
With the help of invertible linear transformations and the known Lie algebras, a higher-dimensional 6 x 6 matrix Lie algebra smu(6) is constructed. It follows a type of new loop algebra is presented. By using a (2 + 1)-dimensional partial-differential equation hierarchy we obtain the integrable coupling of the (2 + 1)-dimensional KN integrable hierarchy, then its corresponding Hamiltonian structure is worked out by employing the quadratic-form identity. Furthermore, a higher-dimensional Lie algebra denoted by E, is given by decomposing the Lie algebra smu(6), then a discrete lattice integrable coupling system is produced. A remarkable feature of the Lie algebras smu(6) and E is used to directly construct integrable couplings.
Pair creation of higher dimensional black holes on a de Sitter background
International Nuclear Information System (INIS)
Dias, Oscar J.C.; Lemos, Jose P.S.
2004-01-01
We study in detail the quantum process in which a pair of black holes is created in a higher D-dimensional de Sitter (dS) background. The energy to materialize and accelerate the pair comes from the positive cosmological constant. The instantons that describe the process are obtained from the Tangherlini black hole solutions. Our pair creation rates reduce to the pair creation rate for Reissner-Nordstroem-dS solutions when D=4. Pair creation of black holes in the dS background becomes less suppressed when the dimension of the spacetime increases. The dS space is the only background in which we can discuss analytically the pair creation process of higher dimensional black holes, since the C-metric and the Ernst solutions, which describe, respectively, a pair accelerated by a string and by an electromagnetic field, are not known yet in a higher dimensional spacetime
International Nuclear Information System (INIS)
Pollock, M.D.
1988-01-01
We consider super-exponential inflation in the early universe, for which H 2 /H = q >> 1, with particular reference to the higher-dimensional theory of Shafi and Wetterich, which is discussed in further detail. The Hubble parameter H is given by H 2 ≅ (8π/3m P 2 )V(Φ), where the ''inflation'' field Φ is related to the radius of the internal space, and obeys the equation of motion 3HΦ ≅ -dW/dΦ. The spectrum of density perturbations is given by δρ/ρ = (M/M 0 ) -s , where s -1 ≅ 3(q + 1); and X = (-dV/dΦ)/(dW/dΦ). The parameters q and X are both positive constants, hence the need for two distinct potentials, which can be met in a higher-dimensional theory with higher-derivative terms R 2 = α 1 R 2 + α 2 R AB R AB + α 3 R ABCD R ABCD . Some fine-tuning of the parameters α i and/or of the cosmological constant Λ is always necessary in order to have super-exponential inflation. It is possible to obtain a spectrum of density perturbations with s > or approx. 1/20, which helps to give agreement with observations of the cosmic microwave background radiation at very large scales ∝ 1000 Mpc. When R 2 is proportional to the Euler number density, making the four-dimensional theory free of ghosts, then super-exponential inflation is impossible, but a phase of inflation with H < 0 can still occur. (orig.)
International Nuclear Information System (INIS)
Groot Nibbelink, Stefan; Hillenbach, Mark
2005-01-01
We consider supersymmetric gauge theories coupled to hypermultiplets on five- and six-dimensional orbifolds and determine the bulk and local fixed point renormalizations of the gauge couplings. We infer from a component analysis that the hypermultiplet does not induce renormalization of the brane gauge couplings on the five-dimensional orbifold S 1 /Z 2 . This is not due to supersymmetry, since the bosonic and fermionic contributions cancel separately. We extend this investigation to T 2 /Z N orbifolds using supergraph techniques in six dimensions. On general Z N orbifolds the gauge couplings do renormalize at the fixed points, except for the Z 2 fixed points of even ordered orbifolds. To cancel the bulk one-loop divergences a dimension six higher derivative operator is needed, in addition to the standard bulk gauge kinetic term.
Baxley, B.; Williams, D.; Consiglio, M.; Conway, S.; Adams, C.; Abbott, T.
2005-01-01
The ability to conduct concurrent, multiple aircraft operations in poor weather, at virtually any airport, offers an important opportunity for a significant increase in the rate of flight operations, a major improvement in passenger convenience, and the potential to foster growth of charter operations at small airports. The Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept is designed to increase traffic flow at any of the 3400 nonradar, non-towered airports in the United States where operations are currently restricted to one-in/one-out procedural separation during Instrument Meteorological Conditions (IMC). The concept's key feature is pilots maintain their own separation from other aircraft using procedures, aircraft flight data sent via air-to-air datalink, cockpit displays, and on-board software. This is done within the Self-Controlled Area (SCA), an area of flight operations established during poor visibility or low ceilings around an airport without Air Traffic Control (ATC) services. The research described in this paper expands the HVO concept to include most off-nominal situations that could be expected to occur in a future SATS environment. The situations were categorized into routine off-nominal operations, procedural deviations, equipment malfunctions, and aircraft emergencies. The combination of normal and off-nominal HVO procedures provides evidence for an operational concept that is safe, requires little ground infrastructure, and enables concurrent flight operations in poor weather.
Schure, Mark R; Davis, Joe M
2017-11-10
Orthogonality metrics (OMs) for three and higher dimensional separations are proposed as extensions of previously developed OMs, which were used to evaluate the zone utilization of two-dimensional (2D) separations. These OMs include correlation coefficients, dimensionality, information theory metrics and convex-hull metrics. In a number of these cases, lower dimensional subspace metrics exist and can be readily calculated. The metrics are used to interpret previously generated experimental data. The experimental datasets are derived from Gilar's peptide data, now modified to be three dimensional (3D), and a comprehensive 3D chromatogram from Moore and Jorgenson. The Moore and Jorgenson chromatogram, which has 25 identifiable 3D volume elements or peaks, displayed good orthogonality values over all dimensions. However, OMs based on discretization of the 3D space changed substantially with changes in binning parameters. This example highlights the importance in higher dimensions of having an abundant number of retention times as data points, especially for methods that use discretization. The Gilar data, which in a previous study produced 21 2D datasets by the pairing of 7 one-dimensional separations, was reinterpreted to produce 35 3D datasets. These datasets show a number of interesting properties, one of which is that geometric and harmonic means of lower dimensional subspace (i.e., 2D) OMs correlate well with the higher dimensional (i.e., 3D) OMs. The space utilization of the Gilar 3D datasets was ranked using OMs, with the retention times of the datasets having the largest and smallest OMs presented as graphs. A discussion concerning the orthogonality of higher dimensional techniques is given with emphasis on molecular diversity in chromatographic separations. In the information theory work, an inconsistency is found in previous studies of orthogonality using the 2D metric often identified as %O. A new choice of metric is proposed, extended to higher dimensions
World-volume effective theory for higher-dimensional black holes.
Emparan, Roberto; Harmark, Troels; Niarchos, Vasilis; Obers, Niels A
2009-05-15
We argue that the main feature behind novel properties of higher-dimensional black holes, compared to four-dimensional ones, is that their horizons can have two characteristic lengths of very different size. We develop a long-distance world-volume effective theory that captures the black hole dynamics at scales much larger than the short scale. In this limit the black hole is regarded as a blackfold: a black brane (possibly boosted locally) whose world volume spans a curved submanifold of the spacetime. This approach reveals black objects with novel horizon geometries and topologies more complex than the black ring, but more generally it provides a new organizing framework for the dynamics of higher-dimensional black holes.
Toeplitz operators on higher Cauchy-Riemann spaces
Czech Academy of Sciences Publication Activity Database
Engliš, Miroslav; Zhang, G.
2017-01-01
Roč. 22, č. 22 (2017), s. 1081-1116 ISSN 1431-0643 Institutional support: RVO:67985840 Keywords : Toeplitz operator * Hankel operator * Cauchy-Riemann operators Subject RIV: BA - General Math ematics OBOR OECD: Pure math ematics Impact factor: 0.800, year: 2016 https://www. math .uni-bielefeld.de/documenta/vol-22/32.html
The solutions of the n-dimensional Bessel diamond operator and the ...
Indian Academy of Sciences (India)
R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22
Introduction. Gelfand and Shilov [2] have first introduced the elementary solution of the n-dimensional classical diamond operator. Later, Kananthai [3–5] has proved the distribution related to the n-dimensional ultra-hyperbolic equation, the solutions of n-dimensional classical diamond operator and Fourier transformation of ...
International Nuclear Information System (INIS)
Richins, W.D.; Snow, S.D.; Miller, G.K.; Russell, M.J.; Ware, A.G.
1995-12-01
Some motor operated valves now have higher torque switch settings due to regulatory requirements to ensure valve operability with appropriate margins at design basis conditions. Verifying operability with these settings imposes higher stem loads during periodic inservice testing. These higher test loads increase stresses in the various valve internal parts which may in turn increase the fatigue usage factors. This increased fatigue is judged to be a concern primarily in the valve disks, seats, yokes, stems, and stem nuts. Although the motor operators may also have significantly increased loading, they are being evaluated by the manufacturers and are beyond the scope of this study. Two gate valves representative of both relatively weak and strong valves commonly used in commercial nuclear applications were selected for fatigue analyses. Detailed dimensional and test data were available for both valves from previous studies at the Idaho National Engineering Laboratory. Finite element models were developed to estimate maximum stresses in the internal parts of the valves and to identity the critical areas within the valves where fatigue may be a concern. Loads were estimated using industry standard equations for calculating torque switch settings prior and subsequent to the testing requirements of USNRC Generic Letter 89--10. Test data were used to determine both; (1) the overshoot load between torque switch trip and final seating of the disk during valve closing and (2) the stem thrust required to open the valves. The ranges of peak stresses thus determined were then used to estimate the increase in the fatigue usage factors due to the higher stem thrust loads. The usages that would be accumulated by 100 base cycles plus one or eight test cycles per year over 40 and 60 years of operation were calculated
A Three-Dimensional Receiver Operator Characteristic Surface Diagnostic Metric
Simon, Donald L.
2011-01-01
Receiver Operator Characteristic (ROC) curves are commonly applied as metrics for quantifying the performance of binary fault detection systems. An ROC curve provides a visual representation of a detection system s True Positive Rate versus False Positive Rate sensitivity as the detection threshold is varied. The area under the curve provides a measure of fault detection performance independent of the applied detection threshold. While the standard ROC curve is well suited for quantifying binary fault detection performance, it is not suitable for quantifying the classification performance of multi-fault classification problems. Furthermore, it does not provide a measure of diagnostic latency. To address these shortcomings, a novel three-dimensional receiver operator characteristic (3D ROC) surface metric has been developed. This is done by generating and applying two separate curves: the standard ROC curve reflecting fault detection performance, and a second curve reflecting fault classification performance. A third dimension, diagnostic latency, is added giving rise to 3D ROC surfaces. Applying numerical integration techniques, the volumes under and between the surfaces are calculated to produce metrics of the diagnostic system s detection and classification performance. This paper will describe the 3D ROC surface metric in detail, and present an example of its application for quantifying the performance of aircraft engine gas path diagnostic methods. Metric limitations and potential enhancements are also discussed
Higher derivative operators from Scherk-Schwarz supersymmetry breaking on Τ2/Z2
International Nuclear Information System (INIS)
Ghilencea, D.M.
2005-09-01
In orbifold compactifications on Τ 2 /Z 2 with Scherk-Schwarz supersymmetry breaking, it is shown that (brane-localised) superpotential interactions and (bulk) gauge interactions generate at one-loop higher derivative counterterms to the mass of the brane (or zero-mode of the bulk) scalar field. These brane-localised operators are generated by integrating out the bulk modes of the initial theory which, although supersymmetric, is nevertheless non-renormalisable. It is argued that such operators, of non-perturbative origin and not protected by non-renormalisation theorems, are generic in orbifold compactifications and play a crucial role in the UV behaviour of the two-point Green function of the scalar field self-energy. Their presence in the action with unknown coefficients prevents one from making predictions about physics at (momentum) scales close to/above the compactification scale(s). Our results extend to the case of two dimensional orbifolds, previous findings for S 1 /Z 2 and S 1 /(Z 2 x Z 2 ') compactifications where brane-localised higher derivative operators are also dynamically generated at loop level, regardless of the details of the supersymmetry breaking mechanism. We stress the importance of these operators for the hierarchy and the cosmological constant problems in compactified theories. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Dai Jian [Theory Group, Department of Physics, Peking University, Beijing (China)]. E-mail: jdai@mail.phy.pku.edu.cn; Song Xingchang [Theory Group, Department of Physics, Peking University, Beijing (China)]. E-mail: songxc@ibm320h.phy.pku.edu.cn
2001-07-13
One of the key ingredients of Connes's noncommutative geometry is a generalized Dirac operator which induces a metric (Connes's distance) on the pure state space. We generalize such a Dirac operator devised by Dimakis et al, whose Connes distance recovers the linear distance on an one-dimensional lattice, to the two-dimensional case. This Dirac operator has the local eigenvalue property and induces a Euclidean distance on this two-dimensional lattice, which is referred to as 'natural'. This kind of Dirac operator can be easily generalized into any higher-dimensional lattices. (author)
Commutative curvature operators over four-dimensional generalized symmetric
Directory of Open Access Journals (Sweden)
Ali Haji-Badali
2014-12-01
Full Text Available Commutative properties of four-dimensional generalized symmetric pseudo-Riemannian manifolds were considered. Specially, in this paper, we studied Skew-Tsankov and Jacobi-Tsankov conditions in 4-dimensional pseudo-Riemannian generalized symmetric manifolds.
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
Asymptotic analysis of fundamental solutions of Dirac operators on even dimensional Euclidean spaces
International Nuclear Information System (INIS)
Arai, A.
1985-01-01
We analyze the short distance asymptotic behavior of some quantities formed out of fundamental solutions of Dirac operators on even dimensional Euclidean spaces with finite dimensional matrix-valued potentials. (orig.)
International Nuclear Information System (INIS)
Naumis, Gerardo G.; Bazan, A.; Torres, M.; Aragon, J.L.; Quintero-Torres, R.
2008-01-01
One of the few examples in which the physical properties of an incommensurable system reflect an underlying higher dimensionality is presented. Specifically, we show that the reflectivity distribution of an incommensurable one-dimensional cavity is given by the density of states of a tight-binding Hamiltonian in a two-dimensional triangular lattice. Such effect is due to an independent phase decoupling of the scattered waves, produced by the incommensurable nature of the system, which mimics a random noise generator. This principle can be applied to design a cavity that avoids resonant reflections for almost any incident wave. An optical analogy, by using three mirrors with incommensurable distances between them, is also presented. Such array produces a countable infinite fractal set of reflections, a phenomena which is opposite to the effect of optical invisibility
The universe as a topological defect in a higher-dimensional Einstein-Yang-Mills theory
International Nuclear Information System (INIS)
Nakamura, A.; Shiraishi, K.
1989-04-01
An interpretation is suggested that a spontaneous compactification of space-time can be regarded as a topological defect in a higher-dimensional Einstein-Yang-Mills (EYM) theory. We start with D-dimensional EYM theory in our present analysis. A compactification leads to a D-2 dimensional effective action of Abelian gauge-Higgs theory. We find a 'vortex' solution in the effective theory. Our universe appears to be confined in a center of a 'vortex', which has D-4 large dimensions. In this paper we show an example with SU (2) symmetry in the original EYM theory, and the resulting solution is found to be equivalent to the 'instanton-induced compactification'. The cosmological implication is also mentioned. (author)
Inverse Operation of Four-dimensional Vector Matrix
H J Bao; A J Sang; H X Chen
2011-01-01
This is a new series of study to define and prove multidimensional vector matrix mathematics, which includes four-dimensional vector matrix determinant, four-dimensional vector matrix inverse and related properties. There are innovative concepts of multi-dimensional vector matrix mathematics created by authors with numerous applications in engineering, math, video conferencing, 3D TV, and other fields.
Small Aircraft Transportation System, Higher Volume Operations Concept: Off-Nominal Operations
Abbott, Terence S.; Consiglio, Maria C.; Baxley, Brian T.; Williams, Daniel M.; Conway, Sheila R.
2005-01-01
This document expands the Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept to include off-nominal conditions. The general philosophy underlying the HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA). During periods of poor weather, a block of airspace would be established around designated non-towered, non-radar airports. Aircraft flying enroute to a SATS airport would be on a standard instrument flight rules flight clearance with Air Traffic Control providing separation services. Within the SCA, pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft. Previous work developed the procedures for normal HVO operations. This document provides details for off-nominal and emergency procedures for situations that could be expected to occur in a future SCA.
International Nuclear Information System (INIS)
Oganesian, A.G.
1998-01-01
A method is proposed for estimating unknown vacuum expectation values of high-dimensional operators. The method is based on the idea that the factorization hypothesis is self-consistent. Results are obtained for all vacuum expectation values of dimension-7 operators, and some estimates for dimension-10 operators are presented as well. The resulting values are used to compute corrections of higher dimensions to the Bjorken and Ellis-Jaffe sum rules
International Nuclear Information System (INIS)
Rami, El-Nabulsi Ahmad
2009-01-01
Higher dimensional cosmological implications of a decay law for the cosmological constant term are analyzed. Three independent cosmological models are explored mainly: 1) In the first model, the effective cosmological constant was chosen to decay with times like Δ effective = Ca -2 + D(b/a I ) 2 where a I is an arbitrary scale factor characterizing the isotropic epoch which proceeds the graceful exit period. Further, the extra-dimensional scale factor decays classically like b(t) approx. a x (t), x is a real negative number. 2) In the second model, we adopt in addition to Δ effective = Ca -2 + D(b/a I ) 2 the phenomenological law b(t) = a(t)exp( -Qt) as we expect that at the origin of time, there is no distinction between the visible and extra dimensions; Q is a real number. 3) In the third model, we study a Δ - decaying extra-dimensional cosmology with a static traversable wormhole in which the four-dimensional Friedmann-Robertson-Walker spacetime is subject to the conventional perfect fluid while the extra-dimensional part is endowed by an exotic fluid violating strong energy condition and where the cosmological constant in (3+n+1) is assumed to decays like Δ(a) = 3Ca -2 . The three models are discussed and explored in some details where many interesting points are revealed. (author)
Lohe, M. A.
2018-06-01
We generalize the Watanabe–Strogatz (WS) transform, which acts on the Kuramoto model in d = 2 dimensions, to a higher-dimensional vector transform which operates on vector oscillator models of synchronization in any dimension , for the case of identical frequency matrices. These models have conserved quantities constructed from the cross ratios of inner products of the vector variables, which are invariant under the vector transform, and have trajectories which lie on the unit sphere S d‑1. Application of the vector transform leads to a partial integration of the equations of motion, leaving independent equations to be solved, for any number of nodes N. We discuss properties of complete synchronization and use the reduced equations to derive a stability condition for completely synchronized trajectories on S d‑1. We further generalize the vector transform to a mapping which acts in and in particular preserves the unit ball , and leaves invariant the cross ratios constructed from inner products of vectors in . This mapping can be used to partially integrate a system of vector oscillators with trajectories in , and for d = 2 leads to an extension of the Kuramoto system to a system of oscillators with time-dependent amplitudes and trajectories in the unit disk. We find an inequivalent generalization of the Möbius map which also preserves but leaves invariant a different set of cross ratios, this time constructed from the vector norms. This leads to a different extension of the Kuramoto model with trajectories in the complex plane that can be partially integrated by means of fractional linear transformations.
Fu, Yuchen; Shelley-Abrahamson, Seth
2016-06-01
We give explicit constructions of some finite-dimensional representations of generalized double affine Hecke algebras (GDAHA) of higher rank using R-matrices for U_q(sl_N). Our construction is motivated by an analogous construction of Silvia Montarani in the rational case. Using the Drinfeld-Kohno theorem for Knizhnik-Zamolodchikov differential equations, we prove that the explicit representations we produce correspond to Montarani's representations under a monodromy functor introduced by Etingof, Gan, and Oblomkov.
Using Harry Potter to Bridge Higher Dimensionality in Mathematics and High-interest Literature
Boerman-Cornell, William; Klanderman, David; Schut, Alexa
2017-01-01
The Harry Potter series is a favorite for out-of-school reading and has been used in school, largely as an object of study in language arts. Using a content analysis to highlight the ways in which J.K. Rowling's work could be used to teach higher dimensionality in math, the authors argues that the content is sufficient in such books to engage the…
Existence of local degrees of freedom for higher dimensional pure Chern-Simons theories
International Nuclear Information System (INIS)
Banados, M.; Garay, L.J.; Henneaux, M.
1996-01-01
The canonical structure of higher dimensional pure Chern-Simons theories is analyzed. It is shown that these theories have generically a nonvanishing number of local degrees of freedom, even though they are obtained by means of a topological construction. This number of local degrees of freedom is computed as a function of the spacetime dimension and the dimension of the gauge group. copyright 1996 The American Physical Society
On higher dimensional Einstein spacetimes with a non-degenerate double Weyl aligned null direction
Czech Academy of Sciences Publication Activity Database
Ortaggio, Marcello; Pravda, Vojtěch; Pravdová, Alena
Roč. 35, č. 7 ( 2018 ), č. článku 075004. ISSN 0264-9381 R&D Projects: GA ČR GB14-37086G Institutional support: RVO:67985840 Keywords : higher-dimensional gravity * WANDs * Weyl tensor Subject RIV: BA - General Mathematics OBOR OECD: Applied mathematics Impact factor: 3.119, year: 2016 http://iopscience.iop.org/article/10.1088/1361-6382/aaae25
Higher dimensional quantum Hall effect as A-class topological insulator
Energy Technology Data Exchange (ETDEWEB)
Hasebe, Kazuki, E-mail: khasebe@stanford.edu
2014-09-15
We perform a detail study of higher dimensional quantum Hall effects and A-class topological insulators with emphasis on their relations to non-commutative geometry. There are two different formulations of non-commutative geometry for higher dimensional fuzzy spheres: the ordinary commutator formulation and quantum Nambu bracket formulation. Corresponding to these formulations, we introduce two kinds of monopole gauge fields: non-abelian gauge field and antisymmetric tensor gauge field, which respectively realize the non-commutative geometry of fuzzy sphere in the lowest Landau level. We establish connection between the two types of monopole gauge fields through Chern–Simons term, and derive explicit form of tensor monopole gauge fields with higher string-like singularity. The connection between two types of monopole is applied to generalize the concept of flux attachment in quantum Hall effect to A-class topological insulator. We propose tensor type Chern–Simons theory as the effective field theory for membranes in A-class topological insulators. Membranes turn out to be fractionally charged objects and the phase entanglement mediated by tensor gauge field transforms the membrane statistics to be anyonic. The index theorem supports the dimensional hierarchy of A-class topological insulator. Analogies to D-brane physics of string theory are discussed too.
International Nuclear Information System (INIS)
Steinberg, S.; Wolf, K.B.
1979-01-01
The authors study the construction and action of certain Lie algebras of second- and higher-order differential operators on spaces of solutions of well-known parabolic, hyperbolic and elliptic linear differential equations. The latter include the N-dimensional quadratic quantum Hamiltonian Schroedinger equations, the one-dimensional heat and wave equations and the two-dimensional Helmholtz equation. In one approach, the usual similarity first-order differential operator algebra of the equation is embedded in the larger one, which appears as a quantum-mechanical dynamic algebra. In a second approach, the new algebra is built as the time evolution of a finite-transformation algebra on the initial conditions. In a third approach, the algebra to inhomogeneous similarity algebra is deformed to a noncompact classical one. In every case, we can integrate the algebra to a Lie group of integral transforms acting effectively on the solution space of the differential equation. (author)
Higher order BLG supersymmetry transformations from 10-dimensional super Yang Mills
Energy Technology Data Exchange (ETDEWEB)
Hall, John [Alumnus of Physics Department, Imperial College,South Kensington, London, SW7 2AZ (United Kingdom); Low, Andrew [Physics Department, Wimbledon High School,Mansel Road, London, SW19 4AB (United Kingdom)
2014-06-26
We study a Simple Route for constructing the higher order Bagger-Lambert-Gustavsson theory - both supersymmetry transformations and Lagrangian - starting from knowledge of only the 10-dimensional Super Yang Mills Fermion Supersymmetry transformation. We are able to uniquely determine the four-derivative order corrected supersymmetry transformations, to lowest non-trivial order in Fermions, for the most general three-algebra theory. For the special case of Euclidean three-algbera, we reproduce the result presented in arXiv:1207.1208, with significantly less labour. In addition, we apply our method to calculate the quadratic fermion terms in the higher order BLG fermion supersymmetry transformation.
Extension of the TCV Operating Space Towards Higher Elongation and Higher Normalized Current
International Nuclear Information System (INIS)
Hofmann, F.; Coda, S.; Lavanchy, P.; Llobet, X.; Marmillod, Ph.; Martin, Y.; Martynov, A.; Mlynar, J.; Moret, J.-M.; Pochelon, A.; Sauter, O.
2002-01-01
Recently, an experimental campaign has been launched on TCV with the aim of exploring and extending the limits of the operating space. The vertical position control system has been optimized, with the help of extensive model calculations, in order to allow operation at the lowest possible stability margin. In addition, the growth rate of the axisymmetric instability has been minimized by choosing optimum values for the plasma triangularity and squareness and by operating close to the current limit imposed by the n= 1 external kink mode. These measures have allowed us to reach record values of elongation, κ=2.8, and normalized current, I N =3.6, in a tokamak with standard aspect ratio, R/a=3.5. (author)
Higher-dimensional bulk wormholes and their manifestations in brane worlds
International Nuclear Information System (INIS)
Rodrigo, Enrico
2006-01-01
There is nothing to prevent a higher-dimensional anti-de Sitter bulk spacetime from containing various other branes in addition to hosting our universe, presumed to be a positive-tension 3-brane. In particular, it could contain closed, microscopic branes that form the boundary surfaces of void bubbles and thus violate the null energy condition in the bulk. The possible existence of such micro branes can be investigated by considering the properties of the ground state of a pseudo-Wheeler-DeWitt equation describing brane quantum dynamics in minisuperspace. If they exist, a concentration of these micro branes could act as a fluid of exotic matter able to support macroscopic wormholes connecting otherwise-distant regions of the bulk. Were the brane constituting our universe to expand into a region of the bulk containing such higher-dimensional macroscopic wormholes, they would likely manifest themselves in our brane as wormholes of normal dimensionality, whose spontaneous appearance and general dynamics would seem inexplicably peculiar. This encounter could also result in the formation of baby universes of a particular type
Vacuum polarization and classical self-action near higher-dimensional defects
Energy Technology Data Exchange (ETDEWEB)
Grats, Yuri V.; Spirin, Pavel [Moscow State University, Department of Theoretical Physics, Faculty of Physics, Moscow (Russian Federation)
2017-02-15
We analyze the gravity-induced effects associated with a massless scalar field in a higher-dimensional spacetime being the tensor product of (d - n)-dimensional Minkowski space and n-dimensional spherically/cylindrically symmetric space with a solid/planar angle deficit. These spacetimes are considered as simple models for a multidimensional global monopole (if n ≥ 3) or cosmic string (if n = 2) with (d - n - 1) flat extra dimensions. Thus, we refer to them as conical backgrounds. In terms of the angular-deficit value, we derive the perturbative expression for the scalar Green function, valid for any d ≥ 3 and 2 ≤ n ≤ d - 1, and compute it to the leading order. With the use of this Green function we compute the renormalized vacuum expectation value of the field square left angle φ{sup 2}(x) right angle {sub ren} and the renormalized vacuum averaged of the scalar-field energy-momentum tensor left angle T{sub MN}(x) right angle {sub ren} for arbitrary d and n from the interval mentioned above and arbitrary coupling constant to the curvature ξ. In particular, we revisit the computation of the vacuum polarization effects for a non-minimally coupled massless scalar field in the spacetime of a straight cosmic string. The same Green function enables to consider the old purely classical problem of the gravity-induced self-action of a classical point-like scalar or electric charge, placed at rest at some fixed point of the space under consideration. To deal with divergences, which appear in consideration of the two problems, we apply the dimensional-regularization technique, widely used in quantum field theory. The explicit dependence of the results upon the dimensionalities of both the bulk and conical submanifold is discussed. (orig.)
Bulk emission by higher-dimensional black holes: almost perfect blackbody radiation
International Nuclear Information System (INIS)
Hod, Shahar
2011-01-01
We study the Hawking radiation emitted into the bulk by (D + 1)-dimensional Schwarzschild black holes. It is well known that the black-hole spectrum departs from exact blackbody form due to the frequency dependence of the 'greybody' factors. For intermediate values of D (3 ≤ D ∼ > 1, the typical wavelengths in the black-hole spectrum are much shorter than the size of the black hole. In this regime, the greybody factors are well described by the geometric-optics approximation according to which they are almost frequency independent. Following this observation, we argue that for higher-dimensional black holes with D >> 1, the total power emitted into the bulk should be well approximated by the analytical formula for perfect blackbody radiation. We test the validity of this analytical prediction with numerical computations.
New classes of bi-axially symmetric solutions to four-dimensional Vasiliev higher spin gravity
Energy Technology Data Exchange (ETDEWEB)
Sundell, Per; Yin, Yihao [Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago de Chile (Chile)
2017-01-11
We present new infinite-dimensional spaces of bi-axially symmetric asymptotically anti-de Sitter solutions to four-dimensional Vasiliev higher spin gravity, obtained by modifications of the Ansatz used in https://arxiv.org/abs/1107.1217, which gave rise to a Type-D solution space. The current Ansatz is based on internal semigroup algebras (without identity) generated by exponentials formed out of the bi-axial symmetry generators. After having switched on the vacuum gauge function, the resulting generalized Weyl tensor is given by a sum of generalized Petrov type-D tensors that are Kerr-like or 2-brane-like in the asymptotic AdS{sub 4} region, and the twistor space connection is smooth in twistor space over finite regions of spacetime. We provide evidence for that the linearized twistor space connection can be brought to Vasiliev gauge.
Higher order Riesz transforms associated with Bessel operators
Betancor, Jorge J.; Fariña, Juan C.; Martinez, Teresa; Rodríguez-Mesa, Lourdes
2008-10-01
In this paper we investigate Riesz transforms R μ ( k) of order k≥1 related to the Bessel operator Δμ f( x)=- f”( x)-((2μ+1)/ x) f’( x) and extend the results of Muckenhoupt and Stein for the conjugate Hankel transform (a Riesz transform of order one). We obtain that for every k≥1, R μ ( k) is a principal value operator of strong type ( p, p), p∈(1,∞), and weak type (1,1) with respect to the measure dλ( x)= x 2μ+1 dx in (0,∞). We also characterize the class of weights ω on (0,∞) for which R μ ( k) maps L p (ω) into itself and L 1(ω) into L 1,∞(ω) boundedly. This class of weights is wider than the Muckenhoupt class mathcal{A}p^μ of weights for the doubling measure dλ. These weighted results extend the ones obtained by Andersen and Kerman.
Metric versus observable operator representation, higher spin models
Fring, Andreas; Frith, Thomas
2018-02-01
We elaborate further on the metric representation that is obtained by transferring the time-dependence from a Hermitian Hamiltonian to the metric operator in a related non-Hermitian system. We provide further insight into the procedure on how to employ the time-dependent Dyson relation and the quasi-Hermiticity relation to solve time-dependent Hermitian Hamiltonian systems. By solving both equations separately we argue here that it is in general easier to solve the former. We solve the mutually related time-dependent Schrödinger equation for a Hermitian and non-Hermitian spin 1/2, 1 and 3/2 model with time-independent and time-dependent metric, respectively. In all models the overdetermined coupled system of equations for the Dyson map can be decoupled algebraic manipulations and reduces to simple linear differential equations and an equation that can be converted into the non-linear Ermakov-Pinney equation.
Energy Technology Data Exchange (ETDEWEB)
Li, Hui-Ling [University of Electronic Science and Technology of China, School of Physical Electronics, Chengdu (China); Shenyang Normal University, College of Physics Science and Technology, Shenyang (China); Feng, Zhong-Wen [China West Normal University, College of Physics and Space Science, Nanchong (China); Zu, Xiao-Tao [University of Electronic Science and Technology of China, School of Physical Electronics, Chengdu (China)
2018-01-15
With motivation by holography, employing black hole entropy, two-point connection function and entanglement entropy, we show that, for the higher-dimensional Anti-de Sitter charged hairy black hole in the fixed charged ensemble, a Van der Waals-like phase transition can be observed. Furthermore, based on the Maxwell equal-area construction, we check numerically the equal-area law for a first order phase transition in order to further characterize the Van der Waals-like phase transition. (orig.)
Directory of Open Access Journals (Sweden)
Muhammad Aslam Noor
2008-01-01
Full Text Available We suggest and analyze a technique by combining the variational iteration method and the homotopy perturbation method. This method is called the variational homotopy perturbation method (VHPM. We use this method for solving higher dimensional initial boundary value problems with variable coefficients. The developed algorithm is quite efficient and is practically well suited for use in these problems. The proposed scheme finds the solution without any discritization, transformation, or restrictive assumptions and avoids the round-off errors. Several examples are given to check the reliability and efficiency of the proposed technique.
A Killing tensor for higher dimensional Kerr-AdS black holes with NUT charge
International Nuclear Information System (INIS)
Davis, Paul
2006-01-01
In this paper, we study the recently discovered family of higher dimensional Kerr-AdS black holes with an extra NUT-like parameter. We show that the inverse metric is additively separable after multiplication by a simple function. This allows us to separate the Hamilton-Jacobi equation, showing that geodesic motion is integrable on this background. The separation of the Hamilton-Jacobi equation is intimately linked to the existence of an irreducible Killing tensor, which provides an extra constant of motion. We also demonstrate that the Klein-Gordon equation for this background is separable
International Nuclear Information System (INIS)
Li, Hui-Ling; Feng, Zhong-Wen; Zu, Xiao-Tao
2018-01-01
With motivation by holography, employing black hole entropy, two-point connection function and entanglement entropy, we show that, for the higher-dimensional Anti-de Sitter charged hairy black hole in the fixed charged ensemble, a Van der Waals-like phase transition can be observed. Furthermore, based on the Maxwell equal-area construction, we check numerically the equal-area law for a first order phase transition in order to further characterize the Van der Waals-like phase transition. (orig.)
International Nuclear Information System (INIS)
Froning, H. David; Meholic, Gregory V.
2010-01-01
This paper briefly explores higher dimensional spacetimes that extend Meholic's visualizable, fluidic views of: subluminal-luminal-superluminal flight; gravity, inertia, light quanta, and electromagnetism from 2-D to 3-D representations. Although 3-D representations have the potential to better model features of Meholic's most fundamental entities (Transluminal Energy Quantum) and of the zero-point quantum vacuum that pervades all space, the more complex 3-D representations loose some of the clarity of Meholic's 2-D representations of subluminal and superlumimal realms. So, much new work would be needed to replace Meholic's 2-D views of reality with 3-D ones.
Grand unified theory precursors and nontrivial fixed points in higher-dimensional gauge theories
International Nuclear Information System (INIS)
Dienes, Keith R.; Dudas, Emilian; Gherghetta, Tony
2003-01-01
Within the context of traditional logarithmic grand unification at M GUT ≅10 16 GeV, we show that it is nevertheless possible to observe certain GUT states such as X and Y gauge bosons at lower scales, perhaps even in the TeV range. We refer to such states as 'GUT precursors'. These states offer an interesting alternative possibility for new physics at the TeV scale, and could be used to directly probe GUT physics even though the scale of gauge coupling unification remains high. Our results also give rise to a Kaluza-Klein realization of nontrivial fixed points in higher-dimensional gauge theories
Spontaneous symmetry breaking and fermion chirality in higher-dimensional gauge theory
International Nuclear Information System (INIS)
Wetterich, C.
1985-01-01
The number of chiral fermions may change in the course of spontaneous symmetry breaking. We discuss solutions of a six-dimensional Einstein-Yang-Mills theory based on SO(12). In the resulting effective four-dimensional theory they can be interpreted as spontaneous breaking of a gauge group SO(10) to H=SU(3)sub(C)xSU(2)sub(L)xU(1)sub(R)xU(1)sub(B-L). For all solutions, the fermions which are chiral with respect to H form standard generations. However, the number of generations for the solutions with broken SO(10) may be different compared to the symmetric solutions. All solutions considered here exhibit a local generation group SU(2)sub(G)xU(1)sub(G). For the solutions with broken SO(10) symmetry, the leptons and quarks within one generation transform differently with respect to SU(2)sub(G)xU(1)sub(G). Spontaneous symmetry breaking also modifies the SO(10) relations among Yukawa couplings. All this has important consequences for possible fermion mass relations obtained from higher-dimensional theories. (orig.)
Upper Estimates on the Higher-dimensional Multifractal Spectrum of Local Entropy%局部熵高维重分形谱的上界估计
Institute of Scientific and Technical Information of China (English)
严珍珍; 陈二才
2008-01-01
We discuss the problem of higher-dimensional multifractal spectrum of lo-cal entropy for arbitrary invariant measures. By utilizing characteristics of a dynam-ical system, namely, higher-dimensional entropy capacities and higher-dimensional correlation entropies, we obtain three upper estimates on the higher-dimensional mul-tifractal spectrum of local entropies. We also study the domain of higher-dimensional multifractal spetrum of entropies.
Generalized Uncertainty Principle and Black Hole Entropy of Higher-Dimensional de Sitter Spacetime
International Nuclear Information System (INIS)
Zhao Haixia; Hu Shuangqi; Zhao Ren; Li Huaifan
2007-01-01
Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-Hawking black hole entropy. In particular, many researchers have expressed a vested interest in the coefficient of the logarithmic term of the black hole entropy correction term. In this paper, we calculate the correction value of the black hole entropy by utilizing the generalized uncertainty principle and obtain the correction term caused by the generalized uncertainty principle. Because in our calculation we think that the Bekenstein-Hawking area theorem is still valid after considering the generalized uncertainty principle, we derive that the coefficient of the logarithmic term of the black hole entropy correction term is positive. This result is different from the known result at present. Our method is valid not only for four-dimensional spacetimes but also for higher-dimensional spacetimes. In the whole process, the physics idea is clear and calculation is simple. It offers a new way for studying the entropy correction of the complicated spacetime.
Black holes in higher dimensional gravity theory with corrections quadratic in curvature
International Nuclear Information System (INIS)
Frolov, Valeri P.; Shapiro, Ilya L.
2009-01-01
Static spherically symmetric black holes are discussed in the framework of higher dimensional gravity with quadratic in curvature terms. Such terms naturally arise as a result of quantum corrections induced by quantum fields propagating in the gravitational background. We focus our attention on the correction of the form C 2 =C αβγδ C αβγδ . The Gauss-Bonnet equation in four-dimensional spacetime enables one to reduce this term in the action to the terms quadratic in the Ricci tensor and scalar curvature. As a result the Schwarzschild solution which is Ricci flat will be also a solution of the theory with the Weyl scalar C 2 correction. An important new feature of the spaces with dimension D>4 is that in the presence of the Weyl curvature-squared term a necessary solution differs from the corresponding 'classical' vacuum Tangherlini metric. This difference is related to the presence of secondary or induced hair. We explore how the Tangherlini solution is modified by 'quantum corrections', assuming that the gravitational radius r 0 is much larger than the scale of the quantum corrections. We also demonstrated that finding a general solution beyond the perturbation method can be reduced to solving a single third order ordinary differential equation (master equation).
A three-dimensional Dirichlet-to-Neumann operator for water waves over topography
Andrade, D.; Nachbin, A.
2018-06-01
Surface water waves are considered propagating over highly variable non-smooth topographies. For this three dimensional problem a Dirichlet-to-Neumann (DtN) operator is constructed reducing the numerical modeling and evolution to the two dimensional free surface. The corresponding Fourier-type operator is defined through a matrix decomposition. The topographic component of the decomposition requires special care and a Galerkin method is provided accordingly. One dimensional numerical simulations, along the free surface, validate the DtN formulation in the presence of a large amplitude, rapidly varying topography. An alternative, conformal mapping based, method is used for benchmarking. A two dimensional simulation in the presence of a Luneburg lens (a particular submerged mound) illustrates the accurate performance of the three dimensional DtN operator.
Higher-dimensional black holes: hidden symmetries and separation of variables
International Nuclear Information System (INIS)
Frolov, Valeri P; Kubiznak, David
2008-01-01
In this paper, we discuss hidden symmetries in rotating black hole spacetimes. We start with an extended introduction which mainly summarizes results on hidden symmetries in four dimensions and introduces Killing and Killing-Yano tensors, objects responsible for hidden symmetries. We also demonstrate how starting with a principal CKY tensor (that is a closed non-degenerate conformal Killing-Yano 2-form) in 4D flat spacetime one can 'generate' the 4D Kerr-NUT-(A)dS solution and its hidden symmetries. After this we consider higher-dimensional Kerr-NUT-(A)dS metrics and demonstrate that they possess a principal CKY tensor which allows one to generate the whole tower of Killing-Yano and Killing tensors. These symmetries imply complete integrability of geodesic equations and complete separation of variables for the Hamilton-Jacobi, Klein-Gordon and Dirac equations in the general Kerr-NUT-(A)dS metrics
Principal Killing strings in higher-dimensional Kerr-NUT-(A)dS spacetimes
Boos, Jens; Frolov, Valeri P.
2018-04-01
We construct special solutions of the Nambu-Goto equations for stationary strings in a general Kerr-NUT-(A)dS spacetime in any number of dimensions. This construction is based on the existence of explicit and hidden symmetries generated by the principal tensor which exists for these metrics. The characteristic property of these string configurations, which we call "principal Killing strings," is that they are stretched out from "infinity" to the horizon of the Kerr-NUT-(A)dS black hole and remain regular at the latter. We also demonstrate that principal Killing strings extract angular momentum from higher-dimensional rotating black holes and interpret this as the action of an asymptotic torque.
The effective action for edge states in higher-dimensional quantum Hall systems
International Nuclear Information System (INIS)
Karabali, Dimitra; Nair, V.P.
2004-01-01
We show that the effective action for the edge excitations of a quantum Hall droplet of fermions in higher dimensions is generically given by a chiral bosonic action. We explicitly analyze the quantum Hall effect on complex projective spaces CP k , with a U(1) background magnetic field. The edge excitations are described by Abelian bosonic fields on S 2k-1 with only one spatial direction along the boundary of the droplet relevant for the dynamics. Our analysis also leads to an action for edge excitations for the case of the Zhang-Hu four-dimensional quantum Hall effect defined on S 4 with an SU(2) background magnetic field, using the fact that CP 3 is an S 2 -bundle over S 4
Construction of two-dimensional Schrodinger operator with given scattering amplitude at fixed energy
International Nuclear Information System (INIS)
Novikov, R.G.
1986-01-01
The classical necessary properties of the scattering amplitude (reciprocity and unitarity) are, provided its L 2 norm is small, sufficient for the existence of a two-dimensional Schrodinger operator with the given scattering amplitude at fixed energy
Exact solutions of Einstein and Einstein-Maxwell equations in higher-dimensional spacetime
International Nuclear Information System (INIS)
Xu Dianyan; Beijing Univ., BJ
1988-01-01
The D-dimensional Schwarzschild-de Sitter metric and Reissner-Nordstrom-de-Sitter metric are derived directly by solving the Einstein and Einstein-Maxwell equations. The D-dimensional Kerr metric is rederived by using the complex coordinate transformation method and the D-dimensional Kerr-de Sitter metric is also given. The conjecture about the D-dimensional metric of a rotating charged mass is given at the end of this paper. (author)
Higher operational safety of nuclear power plants by evaluating the behaviour of operating personnel
International Nuclear Information System (INIS)
Mertins, M.; Glasner, P.
1990-01-01
In the GDR power reactors have been operated since 1966. Since that time operational experiences of 73 cumulative reactor years have been collected. The behaviour of operating personnel is an essential factor to guarantee the safety of operation of the nuclear power plant. Therefore a continuous analysis of the behaviour of operating personnel has been introduced at the GDR nuclear power plants. In the paper the overall system of the selection, preparation and control of the behaviour of nuclear power plant operating personnel is presented. The methods concerned are based on recording all errors of operating personnel and on analyzing them in order to find out the reasons. The aim of the analysis of reasons is to reduce the number of errors. By a feedback of experiences the nuclear safety of the nuclear power plant can be increased. All data necessary for the evaluation of errors are recorded and evaluated by a computer program. This method is explained thoroughly in the paper. Selected results of error analysis are presented. It is explained how the activities of the personnel are made safer by means of this analysis. Comparisons with other methods are made. (author). 3 refs, 4 figs
3N scattering in a three-dimensional operator formulation
International Nuclear Information System (INIS)
Gloeckle, W.; Fachruddin, I.; Elster, C.; Golak, J.; Skibinski, R.; Witala, H.
2010-01-01
A recently developed formulation for a direct treatment of the equations for two- and three-nucleon bound states as set of coupled equations of scalar functions depending only on vector momenta is extended to three-nucleon scattering. Starting from the spin-momentum dependence occurring as scalar products in two- and three-nucleon forces together with other scalar functions, we present the Faddeev multiple scattering series in which order by order the spin degrees can be treated analytically leading to 3D integrations over scalar functions depending on momentum vectors only. Such formulation is especially important in view of awaiting extension of 3N Faddeev calculations to projectile energies above the pion production threshold and applications of chiral perturbation theory 3N forces, which are to be most efficiently treated directly in such three-dimensional formulation without having to expand these forces into a partial-wave basis. (orig.)
Three-dimensional freak waves and higher-order wave-wave resonances
Badulin, S. I.; Ivonin, D. V.; Dulov, V. A.
2012-04-01
Quite often the freak wave phenomenon is associated with the mechanism of modulational (Benjamin-Feir) instability resulted from resonances of four waves with close directions and scales. This weakly nonlinear model reflects some important features of the phenomenon and is discussing in a great number of studies as initial stage of evolution of essentially nonlinear water waves. Higher-order wave-wave resonances attract incomparably less attention. More complicated mathematics and physics explain this disregard partially only. The true reason is a lack of adequate experimental background for the study of essentially three-dimensional water wave dynamics. We start our study with the classic example of New Year Wave. Two extreme events: the famous wave 26.5 meters and one of smaller 18.5 meters height (formally, not freak) of the same record, are shown to have pronounced features of essentially three-dimensional five-wave resonant interactions. The quasi-spectra approach is used for the data analysis in order to resolve adequately frequencies near the spectral peak fp ≈ 0.057Hz and, thus, to analyze possible modulations of the dominant wave component. In terms of the quasi-spectra the above two anomalous waves show co-existence of the peak harmonic and one at frequency f5w = 3/2fp that corresponds to maximum of five-wave instability of weakly nonlinear waves. No pronounced marks of usually discussed Benjamin-Feir instability are found in the record that is easy to explain: the spectral peak frequency fp corresponds to the non-dimensional depth parameter kD ≈ 0.92 (k - wavenumber, D ≈ 70 meters - depth at the Statoil platform Draupner site) that is well below the shallow water limit of the instability kD = 1.36. A unique data collection of wave records of the Marine Hydrophysical Institute in the Katsiveli platform (Black Sea) has been analyzed in view of the above findings of possible impact of the five-wave instability on freak wave occurrence. The data cover
Towards realistic models from Higher-Dimensional theories with Fuzzy extra dimensions
Gavriil, D.; Zoupanos, G.
2014-01-01
We briefly review the Coset Space Dimensional Reduction (CSDR) programme and the best model constructed so far and then we present some details of the corresponding programme in the case that the extra dimensions are considered to be fuzzy. In particular, we present a four-dimensional $\\mathcal{N} = 4$ Super Yang Mills Theory, orbifolded by $\\mathbb{Z}_3$, which mimics the behaviour of a dimensionally reduced $\\mathcal{N} = 1$, 10-dimensional gauge theory over a set of fuzzy spheres at intermediate high scales and leads to the trinification GUT $SU(3)^3$ at slightly lower, which in turn can be spontaneously broken to the MSSM in low scales.
Fractal zeta functions and fractal drums higher-dimensional theory of complex dimensions
Lapidus, Michel L; Žubrinić, Darko
2017-01-01
This monograph gives a state-of-the-art and accessible treatment of a new general higher-dimensional theory of complex dimensions, valid for arbitrary bounded subsets of Euclidean spaces, as well as for their natural generalization, relative fractal drums. It provides a significant extension of the existing theory of zeta functions for fractal strings to fractal sets and arbitrary bounded sets in Euclidean spaces of any dimension. Two new classes of fractal zeta functions are introduced, namely, the distance and tube zeta functions of bounded sets, and their key properties are investigated. The theory is developed step-by-step at a slow pace, and every step is well motivated by numerous examples, historical remarks and comments, relating the objects under investigation to other concepts. Special emphasis is placed on the study of complex dimensions of bounded sets and their connections with the notions of Minkowski content and Minkowski measurability, as well as on fractal tube formulas. It is shown for the f...
Kanti, P.; Pappas, T.
2017-07-01
The absence of a true thermodynamical equilibrium for an observer located in the causal area of a Schwarzschild-de Sitter spacetime has repeatedly raised the question of the correct definition of its temperature. In this work, we consider five different temperatures for a higher-dimensional Schwarzschild-de Sitter black hole: the bare T0, the normalized TBH, and three effective ones given in terms of both the black-hole and cosmological horizon temperatures. We find that these five temperatures exhibit similarities but also significant differences in their behavior as the number of extra dimensions and the value of the cosmological constant are varied. We then investigate their effect on the energy emission spectra of Hawking radiation. We demonstrate that the radiation spectra for the normalized temperature TBH—proposed by Bousso and Hawking over twenty years ago—leads to the dominant emission curve, while the other temperatures either support a significant emission rate only in a specific Λ regime or have their emission rates globally suppressed. Finally, we compute the bulk-over-brane emissivity ratio and show that the use of different temperatures may lead to different conclusions regarding the brane or bulk dominance.
Emission of massive scalar fields by a higher-dimensional rotating black hole
International Nuclear Information System (INIS)
Kanti, P.; Pappas, N.
2010-01-01
We perform a comprehensive study of the emission of massive scalar fields by a higher-dimensional, simply rotating black hole both in the bulk and on the brane. We derive approximate, analytic results as well as exact numerical ones for the absorption probability, and demonstrate that the two sets agree very well in the low and intermediate-energy regime for scalar fields with mass m Φ ≤1 TeV in the bulk and m Φ ≤0.5 TeV on the brane. The numerical values of the absorption probability are then used to derive the Hawking radiation power emission spectra in terms of the number of extra dimensions, angular-momentum of the black hole and mass of the emitted field. We compute the total emissivities in the bulk and on the brane, and demonstrate that, although the brane channel remains the dominant one, the bulk-over-brane energy ratio is considerably increased (up to 34%) when the mass of the emitted field is taken into account.
What we think about the higher dimensional Chern-Simons theories
International Nuclear Information System (INIS)
Fock, V.V.; Nekrasov, N.A.; Rosly, A.A.; Selivanov, K.G.
1992-01-01
This paper reports that one of the most interesting developments in mathematical physics was the investigation of the so-called topological field theories i.e. such theories which do not need a metric on the manifold for their definition a d hence the observable of which are topologically invariant. The Chern-Simons (CS) functionals considered as actions give us examples the theories of such a type. The CS theory on a 3d manifold was firstly considered in the Abelian case by A.S. Schwartz and then after papers of E. Witten there has been an explosive process of publications on this subject. This paper discusses topological invariants of the manifolds (like the Ray-Singer torsion) computed by the quantum field theory methods; conformal blocks of 2d conformal field theories as vectors in the CS theory Hilbert space; correlators of Wilson loop and the invariants of 1d links in 3d manifolds; braid groups; unusual relations between spin and statistics; here we would like to consider the generalization of a part of the outlined ideas to the CS theories on higher dimensional manifolds. Some of our results intersect with
Partially-massless higher-spin algebras and their finite-dimensional truncations
International Nuclear Information System (INIS)
Joung, Euihun; Mkrtchyan, Karapet
2016-01-01
The global symmetry algebras of partially-massless (PM) higher-spin (HS) fields in (A)dS d+1 are studied. The algebras involving PM generators up to depth 2 (ℓ−1) are defined as the maximal symmetries of free conformal scalar field with 2 ℓ order wave equation in d dimensions. We review the construction of these algebras by quotienting certain ideals in the universal enveloping algebra of (A)dS d+1 isometries. We discuss another description in terms of Howe duality and derive the formula for computing trace in these algebras. This enables us to explicitly calculate the bilinear form for this one-parameter family of algebras. In particular, the bilinear form shows the appearance of additional ideal for any non-negative integer values of ℓ−d/2 , which coincides with the annihilator of the one-row ℓ-box Young diagram representation of so d+2 . Hence, the corresponding finite-dimensional coset algebra spanned by massless and PM generators is equivalent to the symmetries of this representation.
Anderson, Daniel M.; McLaughlin, Richard M.; Miller, Cass T.
2018-02-01
We examine a mathematical model of one-dimensional draining of a fluid through a periodically-layered porous medium. A porous medium, initially saturated with a fluid of a high density is assumed to drain out the bottom of the porous medium with a second lighter fluid replacing the draining fluid. We assume that the draining layer is sufficiently dense that the dynamics of the lighter fluid can be neglected with respect to the dynamics of the heavier draining fluid and that the height of the draining fluid, represented as a free boundary in the model, evolves in time. In this context, we neglect interfacial tension effects at the boundary between the two fluids. We show that this problem admits an exact solution. Our primary objective is to develop a homogenization theory in which we find not only leading-order, or effective, trends but also capture higher-order corrections to these effective draining rates. The approximate solution obtained by this homogenization theory is compared to the exact solution for two cases: (1) the permeability of the porous medium varies smoothly but rapidly and (2) the permeability varies as a piecewise constant function representing discrete layers of alternating high/low permeability. In both cases we are able to show that the corrections in the homogenization theory accurately predict the position of the free boundary moving through the porous medium.
Directory of Open Access Journals (Sweden)
Hasibun Naher
2012-01-01
Full Text Available We construct new analytical solutions of the (3+1-dimensional modified KdV-Zakharov-Kuznetsev equation by the Exp-function method. Plentiful exact traveling wave solutions with arbitrary parameters are effectively obtained by the method. The obtained results show that the Exp-function method is effective and straightforward mathematical tool for searching analytical solutions with arbitrary parameters of higher-dimensional nonlinear partial differential equation.
Higher dimensional models of cross-coupled oscillators and application to design
Elwakil, Ahmed S.; Salama, Khaled N.
2010-01-01
We present four-dimensional and five-dimensional models for classical cross-coupled LC oscillators. Using these models, sinusoidal oscillation condition, frequency and amplitude can be found. Further, undesired behaviors such as relaxation-mode oscillations and latchup can be explained and detected. A simple graphical design procedure is also described. © 2010 World Scientific Publishing Company.
Higher dimensional models of cross-coupled oscillators and application to design
Elwakil, Ahmed S.
2010-06-01
We present four-dimensional and five-dimensional models for classical cross-coupled LC oscillators. Using these models, sinusoidal oscillation condition, frequency and amplitude can be found. Further, undesired behaviors such as relaxation-mode oscillations and latchup can be explained and detected. A simple graphical design procedure is also described. © 2010 World Scientific Publishing Company.
Directory of Open Access Journals (Sweden)
ShuZheng Yang
2016-01-01
Full Text Available Based on semiclassical tunneling method, we focus on charged fermions tunneling from higher-dimensional Reissner-Nordström black hole. We first simplify the Dirac equation by semiclassical approximation, and then a semiclassical Hamilton-Jacobi equation is obtained. Using the Hamilton-Jacobi equation, we study the Hawking temperature and fermions tunneling rate at the event horizon of the higher-dimensional Reissner-Nordström black hole space-time. Finally, the correct entropy is calculation by the method beyond semiclassical approximation.
Unitary W-algebras and three-dimensional higher spin gravities with spin one symmetry
International Nuclear Information System (INIS)
Afshar, Hamid; Creutzig, Thomas; Grumiller, Daniel; Hikida, Yasuaki; Rønne, Peter B.
2014-01-01
We investigate whether there are unitary families of W-algebras with spin one fields in the natural example of the Feigin-Semikhatov W_n"("2")-algebra. This algebra is conjecturally a quantum Hamiltonian reduction corresponding to a non-principal nilpotent element. We conjecture that this algebra admits a unitary real form for even n. Our main result is that this conjecture is consistent with the known part of the operator product algebra, and especially it is true for n=2 and n=4. Moreover, we find certain ranges of allowed levels where a positive definite inner product is possible. We also find a unitary conformal field theory for every even n at the special level k+n=(n+1)/(n−1). At these points, the W_n"("2")-algebra is nothing but a compactified free boson. This family of W-algebras admits an ’t Hooft limit. Further, in the case of n=4, we reproduce the algebra from the higher spin gravity point of view. In general, gravity computations allow us to reproduce some leading coefficients of the operator product.
A higher-dimensional Bianchi type-I inflationary Universe in general ...
Indian Academy of Sciences (India)
Inflation, the stage of accelerated expansion of the Universe, first proposed ... ary model in the context of grand unified theory (GUT), which has been ... The role of self-interacting scalar fields in inflationary cosmology in four-dimensional.
International Nuclear Information System (INIS)
Wang Jisuo; Sun Changyong; He Jinyu
1996-01-01
The eigenstates of the higher power of the annihilation operator a qs k (k≥3) of the two-parameter deformed harmonic oscillator are constructed. Their completeness is demonstrated in terms of the qs-integration
First law of black ring thermodynamics in higher dimensional Chern-Simons gravity
International Nuclear Information System (INIS)
Rogatko, Marek
2007-01-01
The physical process version and the equilibrium state version of the first law of black ring thermodynamics in n-dimensional Einstein gravity with Chern-Simons term were derived. This theory constitutes the simplest generalization of the five-dimensional one admitting a stationary black ring solution. The equilibrium state version of the first law of black ring mechanics was achieved by choosing any cross section of the event horizon to the future of the bifurcation surface
International Nuclear Information System (INIS)
Sembiring, T.M.; Kuntoro, I.
2003-01-01
The core conversion program of the RSG-GAS reactor is to convert the all-oxide to all-silicide core. The silicide equilibrium core with fuel meat density of 3.55 gU cm -3 is an optimal core for RSG-GAS reactor and it can significantly increase the operation cycle length from 25 to 32 full power days. Nevertheless, the subcriticality of the shutdown core and the shutdown margin are lower than of the oxide core. Therefore, the deviation of subcriticality condition in the higher silicide core caused by the fuel loading and shuffling error should be reanalysed. The objective of this work is to analyse the sufficiency of the subcriticality condition of the shutdown core to face the worst condition caused by an error during loading and shuffling operations. The calculations were carried out using the 2-dimensional multigroup neutron diffusion code of Batan-FUEL. In the fuel handling error, the calculated results showed that the subcriticality condition of the shutdown higher density silicide equilibrium core of RSG-GAS can be maintained. Therefore, all fuel management steps are fixed in the present reactor operation manual can be applied in the higher silicide equilibrium core of RSG-GAS reactor. (author)
Hong, Sungwoo
Warped higher-dimensional compactifications with "bulk'' standard model, or their AdS/CFT dual as the purely 4D scenario of Higgs compositeness and partial compositeness, offer an elegant approach to resolving the electroweak hierarchy problem as well as the origins of flavor structure. However, low-energy electroweak/flavor/CP constraints and the absence of non-standard physics at LHC Run 1 suggest that a "little hierarchy problem'' remains, and that the new physics underlying naturalness may lie out of LHC reach. Assuming this to be the case, we show that there is a simple and natural extension of the minimal warped model in the Randall-Sundrum framework, in which matter, gauge and gravitational fields propagate modestly different degrees into the IR of the warped dimension, resulting in rich and striking consequences for the LHC (and beyond). The LHC-accessible part of the new physics is AdS/CFT dual to the mechanism of "vectorlike confinement'', with TeV-scale Kaluza-Klein excitations of the gauge and gravitational fields dual to spin-0,1,2 composites. Unlike the minimal warped model, these low-lying excitations have predominantly flavor-blind and flavor/CP-safe interactions with the standard model. In addition, the usual leading decay modes of the lightest KK gauge bosons into top and Higgs bosons are suppressed. This effect permits erstwhile subdominant channels to become significant. These include flavor-universal decays to all pairs of SM fermions, and a novel channel--decay to a radion and a SM gauge boson, followed by radion decay to a pair of SM gauge bosons. We present a detailed phenomenological study of the latter cascade decay processes. Remarkably, this scenario also predicts small deviations from flavor-blindness originating from virtual effects of Higgs/top compositeness at O(10) TeV, with subdominant resonance decays into a pair of Higgs/top-rich final states, giving the LHC an early "preview'' of the nature of the resolution of the hierarchy
International Nuclear Information System (INIS)
Wiliardy, Abednego; Gunara, Bobby Eka
2016-01-01
An n dimensional flat manifold N is embedded into an n +1 dimensional stationary manifold M. The metric of M is derived from a general form of stationary manifold. By taking several assumption, such as 1) the ambient manifold M to be maximally symmetric space and satisfying a pure gauge condition, and 2) the submanifold is taken to be flat, then we find the solution that satisfies Ricci scalar of N . Moreover, we determine whether the solution is compatible with the Ricci and Riemann tensor of manifold N depending on the dimension. (paper)
Reentrant phase transitions of higher-dimensional AdS black holes in dRGT massive gravity
International Nuclear Information System (INIS)
Zou, De-Cheng; Yue, Ruihong; Zhang, Ming
2017-01-01
We study the P-V criticality and phase transition in the extended phase space of anti-de Sitter (AdS) black holes in higher-dimensional de Rham, Gabadadze and Tolley (dRGT) massive gravity, treating the cosmological constant as pressure and the corresponding conjugate quantity is interpreted as thermodynamic volume. Besides the usual small/large black hole phase transitions, the interesting thermodynamic phenomena of reentrant phase transitions (RPTs) are observed for black holes in all d ≥ 6-dimensional spacetime when the coupling coefficients c_im"2 of massive potential satisfy some certain conditions. (orig.)
Reentrant phase transitions of higher-dimensional AdS black holes in dRGT massive gravity
Energy Technology Data Exchange (ETDEWEB)
Zou, De-Cheng; Yue, Ruihong [Yangzhou University, College of Physical Science and Technology, Yangzhou (China); Zhang, Ming [Xi' an Aeronautical University, Faculty of Science, Xi' an (China)
2017-04-15
We study the P-V criticality and phase transition in the extended phase space of anti-de Sitter (AdS) black holes in higher-dimensional de Rham, Gabadadze and Tolley (dRGT) massive gravity, treating the cosmological constant as pressure and the corresponding conjugate quantity is interpreted as thermodynamic volume. Besides the usual small/large black hole phase transitions, the interesting thermodynamic phenomena of reentrant phase transitions (RPTs) are observed for black holes in all d ≥ 6-dimensional spacetime when the coupling coefficients c{sub i}m{sup 2} of massive potential satisfy some certain conditions. (orig.)
Pappas, T.; Kanti, P.; Pappas, N.
2016-01-01
In this work, we study the propagation of scalar fields in the gravitational background of a higher-dimensional Schwarzschild-de-Sitter black hole as well as on the projected-on-the-brane 4-dimensional background. The scalar fields have also a non-minimal coupling to the corresponding, bulk or brane, scalar curvature. We perform a comprehensive study by deriving exact numerical results for the greybody factors, and study their profile in terms of particle and spacetime properties. We then pro...
Fourier two-level analysis for higher dimensional discontinuous Galerkin discretisation
P.W. Hemker (Piet); M.H. van Raalte (Marc)
2002-01-01
textabstractIn this paper we study the convergence of a multigrid method for the solution of a two-dimensional linear second order elliptic equation, discretized by discontinuous Galerkin (DG) methods. For the Baumann-Oden and for the symmetric DG method, we give a detailed analysis of the
Faster exact algorithms for computing Steiner trees in higher dimensional Euclidean spaces
DEFF Research Database (Denmark)
Fonseca, Rasmus; Brazil, Marcus; Winter, Pawel
The Euclidean Steiner tree problem asks for a network of minimum total length interconnecting a finite set of points in d-dimensional space. For d ≥ 3, only one practical algorithmic approach exists for this problem --- proposed by Smith in 1992. A number of refinements of Smith's algorithm have...
Dimensional reduction of 10d heterotic string effective lagrangian with higher derivative terms
International Nuclear Information System (INIS)
Lalak, Z.; Pawelczyk, J.
1989-11-01
Dimensional reduction of the 10d Supergravity-Yang-Mills theories containing up to four derivatives is described. Unexpected nondiagonal corrections to 4d gauge kinetic function and negative contributions to scalar potential are found. We analyzed the general structure of the resulting lagrangian and discuss the possible phenomenological consequences. (author)
Uniqueness in some higher order elliptic boundary value problems in n dimensional domains
Directory of Open Access Journals (Sweden)
C.-P. Danet
2011-07-01
Full Text Available We develop maximum principles for several P functions which are defined on solutions to equations of fourth and sixth order (including a equation which arises in plate theory and bending of cylindrical shells. As a consequence, we obtain uniqueness results for fourth and sixth order boundary value problems in arbitrary n dimensional domains.
Testud, Frederik; Gallichan, Daniel; Layton, Kelvin J; Barmet, Christoph; Welz, Anna M; Dewdney, Andrew; Cocosco, Chris A; Pruessmann, Klaas P; Hennig, Jürgen; Zaitsev, Maxim
2015-03-01
PatLoc (Parallel Imaging Technique using Localized Gradients) accelerates imaging and introduces a resolution variation across the field-of-view. Higher-dimensional encoding employs more spatial encoding magnetic fields (SEMs) than the corresponding image dimensionality requires, e.g. by applying two quadratic and two linear spatial encoding magnetic fields to reconstruct a 2D image. Images acquired with higher-dimensional single-shot trajectories can exhibit strong artifacts and geometric distortions. In this work, the source of these artifacts is analyzed and a reliable correction strategy is derived. A dynamic field camera was built for encoding field calibration. Concomitant fields of linear and nonlinear spatial encoding magnetic fields were analyzed. A combined basis consisting of spherical harmonics and concomitant terms was proposed and used for encoding field calibration and image reconstruction. A good agreement between the analytical solution for the concomitant fields and the magnetic field simulations of the custom-built PatLoc SEM coil was observed. Substantial image quality improvements were obtained using a dynamic field camera for encoding field calibration combined with the proposed combined basis. The importance of trajectory calibration for single-shot higher-dimensional encoding is demonstrated using the combined basis including spherical harmonics and concomitant terms, which treats the concomitant fields as an integral part of the encoding. © 2014 Wiley Periodicals, Inc.
International Nuclear Information System (INIS)
Kuetche, Victor Kamgang; Bouetou, Thomas Bouetou; Kofane, Timoleon Crepin
2010-12-01
We investigate the singularity structure analysis of the higher-dimensional time-gated Manakov system referring to the (2+1)-dimensional coupled nonlinear Schroedinger (CNLS) equations, and we show that these equations are Painleve-integrable. By means of the Weiss et al.'s methodology, we show the arbitrariness of the expansion coefficients and the consistency of the truncation corresponding to a special Baecklund transformation (BT) of these CNLS equations. In the wake of such transformation, following the Hirota's formalism, we derive a one-soliton solution. Besides, by using the Zakharov-Shabat (ZS) scheme which provides a general Lax-representation of an evolution system, we show that the (2+1)-dimensional CNLS system under interests is completely integrable. Furthermore, using the arbitrariness of the above coefficients, we unearth and investigate a typical spectrum of periodic coherent structures while depicting elastic interactions amongst such patterns. (author)
Maximal locality and predictive power in higher-dimensional, compactified field theories
International Nuclear Information System (INIS)
Kubo, Jisuke; Nunami, Masanori
2004-01-01
To realize maximal locality in a trivial field theory, we maximize the ultraviolet cutoff of the theory by fine tuning the infrared values of the parameters. This optimization procedure is applied to the scalar theory in D + 1 dimensional (D ≥ 4) with one extra dimension compactified on a circle of radius R. The optimized, infrared values of the parameters are then compared with the corresponding ones of the uncompactified theory in D dimensions, which is assumed to be the low-energy effective theory. We find that these values approximately agree with each other as long as R -1 > approx sM is satisfied, where s ≅ 10, 50, 50, 100 for D = 4,5,6,7, and M is a typical scale of the D-dimensional theory. This result supports the previously made claim that the maximization of the ultraviolet cutoff in a nonrenormalizable field theory can give the theory more predictive power. (author)
Higher conservation laws for ten-dimensional supersymmetric Yang-Mills theories
International Nuclear Information System (INIS)
Abdalla, E.; Forger, M.; Freiburg Univ.; Jacques, M.
1988-01-01
It is shown that ten-dimensional supersymmetric Yang-Mills theories are integrable systems, in the (weak) sense of admitting a (superspace) Lax representation for their equations of motion. This is achieved by means of an explicit proof that the equations of motion are not only a consequence of but in fact fully equivalent to the superspace constraint F αβ =0. Moreover, a procedure for deriving infinite series of non-local conservation laws is outlined. (orig.)
Late-time tails of wave propagation in higher dimensional spacetimes
International Nuclear Information System (INIS)
Cardoso, Vitor; Yoshida, Shijun; Dias, Oscar J.C.; Lemos, Jose P.S.
2003-01-01
We study the late-time tails appearing in the propagation of massless fields (scalar, electromagnetic, and gravitational) in the vicinities of a D-dimensional Schwarzschild black hole. We find that at late times the fields always exhibit a power-law falloff, but the power law is highly sensitive to the dimensionality of the spacetime. Accordingly, for odd D>3 we find that the field behaves as t -(2l+D-2) at late times, where l is the angular index determining the angular dependence of the field. This behavior is entirely due to D being odd; it does not depend on the presence of a black hole in the spacetime. Indeed this tail is already present in the flat space Green's function. On the other hand, for even D>4 the field decays as t -(2l+3D-8) , and this time there is no contribution from the flat background. This power law is entirely due to the presence of the black hole. The D=4 case is special and exhibits, as is well known, t -(2l+3) behavior. In the extra dimensional scenario for our Universe, our results are strictly correct if the extra dimensions are infinite, but also give a good description of the late-time behavior of any field if the large extra dimensions are large enough
Yin, Kedong; Yang, Benshuo; Li, Xuemei
2018-01-24
In this paper, we investigate multiple attribute group decision making (MAGDM) problems where decision makers represent their evaluation of alternatives by trapezoidal fuzzy two-dimensional uncertain linguistic variable. To begin with, we introduce the definition, properties, expectation, operational laws of trapezoidal fuzzy two-dimensional linguistic information. Then, to improve the accuracy of decision making in some case where there are a sort of interrelationship among the attributes, we analyze partition Bonferroni mean (PBM) operator in trapezoidal fuzzy two-dimensional variable environment and develop two operators: trapezoidal fuzzy two-dimensional linguistic partitioned Bonferroni mean (TF2DLPBM) aggregation operator and trapezoidal fuzzy two-dimensional linguistic weighted partitioned Bonferroni mean (TF2DLWPBM) aggregation operator. Furthermore, we develop a novel method to solve MAGDM problems based on TF2DLWPBM aggregation operator. Finally, a practical example is presented to illustrate the effectiveness of this method and analyses the impact of different parameters on the results of decision-making.
Scalar QNMs for higher dimensional black holes surrounded by quintessence in Rastall gravity
Energy Technology Data Exchange (ETDEWEB)
Graca, J.P.M.; Lobo, Iarley P. [Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, PB (Brazil)
2018-02-15
The spacetime solution for a black hole, surrounded by an exotic matter field, in Rastall gravity, is calculated in an arbitrary d-dimensional spacetime. After this, we calculate the scalar quasinormal modes of such solution, and study the shift on the modes caused by the modification of the theory of gravity, i.e., by the introduction of a new term due to Rastall. We conclude that the shift strongly depends on the kind of exotic field one is studying, but for a low density matter that supposedly pervades the universe, it is unlikely that Rastall gravity will cause an instability for the probe field. (orig.)
Approaches to analysis of data that concentrate near higher-dimensional manifolds
International Nuclear Information System (INIS)
Friedman, J.H.; Tukey, J.W.; Tukey, P.A.
1979-01-01
The need to explore structure in high-dimensional clouds of data points that may concentrate near (possibly nonlinear) manifolds of lower dimension led to the current development of three new approaches. The first is a computer-graphic system (PRIM'79) that facilitates interactive viewing and manipulation of an ensemble of points. The other two are automatic procedures for separating a cloud into more manageable pieces. One of these (BIDEC) performs successive partitioning of the cloud by use of hyperplanes; the other (Cake Maker) explores expanding sequences of neighborhoods. Both procedures provide facilities for examining the resulting pieces and the relationships among them
Operator algebras for general one-dimensional quantum mechanical potentials with discrete spectrum
International Nuclear Information System (INIS)
Wuensche, Alfred
2002-01-01
We define general lowering and raising operators of the eigenstates for one-dimensional quantum mechanical potential problems leading to discrete energy spectra and investigate their associative algebra. The Hamilton operator is quadratic in these lowering and raising operators and corresponding representations of operators for action and angle are found. The normally ordered representation of general operators using combinatorial elements such as partitions is derived. The introduction of generalized coherent states is discussed. Linear laws for the spacing of the energy eigenvalues lead to the Heisenberg-Weyl group and general quadratic laws of level spacing to unitary irreducible representations of the Lie group SU(1, 1) that is considered in detail together with a limiting transition from this group to the Heisenberg-Weyl group. The relation of the approach to quantum deformations is discussed. In two appendices, the classical and quantum mechanical treatment of the squared tangent potential is presented as a special case of a system with quadratic level spacing
Two-dimensional N=(2,2) lattice gauge theories with matter in higher representations
International Nuclear Information System (INIS)
Joseph, Anosh
2014-06-01
We construct two-dimensional N=(2,2) supersymmetric gauge theories on a Euclidean spacetime lattice with matter in the two-index symmetric and anti-symmetric representations of SU(N c ) color group. These lattice theories preserve a subset of the supercharges exact at finite lattice spacing. The method of topological twisting is used to construct such theories in the continuum and then the geometric discretization scheme is used to formulate them on the lattice. The lattice theories obtained this way are gauge-invariant, free from fermion doubling problem and exact supersymmetric at finite lattice spacing. We hope that these lattice constructions further motivate the nonperturbative explorations of models inspired by technicolor, orbifolding and orientifolding in string theories and the Corrigan-Ramond limit.
Higher first Chern numbers in one-dimensional Bose-Fermi mixtures
Knakkergaard Nielsen, Kristian; Wu, Zhigang; Bruun, G. M.
2018-02-01
We propose to use a one-dimensional system consisting of identical fermions in a periodically driven lattice immersed in a Bose gas, to realise topological superfluid phases with Chern numbers larger than 1. The bosons mediate an attractive induced interaction between the fermions, and we derive a simple formula to analyse the topological properties of the resulting pairing. When the coherence length of the bosons is large compared to the lattice spacing and there is a significant next-nearest neighbour hopping for the fermions, the system can realise a superfluid with Chern number ±2. We show that this phase is stable in a large region of the phase diagram as a function of the filling fraction of the fermions and the coherence length of the bosons. Cold atomic gases offer the possibility to realise the proposed system using well-known experimental techniques.
International Nuclear Information System (INIS)
Park, Chansaem; Zahid, Umer; Lee, Sangho; Han, Chonghun
2015-01-01
Torrefaction reactor model is required for the development of reactor and process design for biomass torrefaction. In this study, a one-dimensional reactor model is developed based on the kinetic model describing volatiles components and solid evolution and the existing thermochemical model considering the heat and mass balance. The developed reactor model used the temperature and flow rate of the recycled gas as the practical manipulated variables instead of the torrefaction temperature. The temperature profiles of the gas and solid phase were generated, depending on the practical thermal conditions, using developed model. Moreover, the effect of each selected operating variables on the parameters of the torrefaction process and the effect of whole operating variables with particular energy yield were analyzed. Through the results of sensitivity analysis, it is shown that the residence time insignificantly influenced the energy yield when the flow rate of recycled gas is low. Moreover, higher temperature of recycled gas with low flow rate and residence time produces the attractive properties, including HHV and grindability, of torrefied biomass when the energy yield is specified. - Highlights: • A one-dimensional reactor model for biomass torrefaction is developed considering the heat and mass balance. • The developed reactor model uses the temperature and flow rate of the recycled gas as the practical manipulated variables. • The effect of operating variables on the parameters of the torrefaction process is analyzed. • The results of sensitivity analysis represent notable discussions which were not done by the previous researches
Pappas, T.; Kanti, P.; Pappas, N.
2016-07-01
In this work, we study the propagation of scalar fields in the gravitational background of a higher-dimensional Schwarzschild-de Sitter black hole as well as on the projected-on-the-brane four-dimensional background. The scalar fields have also a nonminimal coupling to the corresponding, bulk or brane, scalar curvature. We perform a comprehensive study by deriving exact numerical results for the greybody factors, and study their profile in terms of particle and spacetime properties. We then proceed to derive the Hawking radiation spectra for a higher-dimensional Schwarzschild-de Sitter black hole, and we study both bulk and brane channels. We demonstrate that the nonminimal field coupling, which creates an effective mass term for the fields, suppresses the energy emission rates while the cosmological constant assumes a dual role. By computing the relative energy rates and the total emissivity ratio for bulk and brane emission, we demonstrate that the combined effect of a large number of extra dimensions and value of the field coupling gives to the bulk channel the clear domination in the bulk-brane energy balance.
DEFF Research Database (Denmark)
Dahl, Jens Peder; Schleich, W. P.
2009-01-01
For a closed quantum system the state operator must be a function of the Hamiltonian. When the state is degenerate, additional constants of the motion enter the play. But although it is the Weyl transform of the state operator, the Wigner function is not necessarily a function of the Weyl...... transforms of the constants of the motion. We derive conditions for which this is actually the case. The Wigner functions of the energy eigenstates of a two-dimensional isotropic harmonic oscillator serve as an important illustration....
Spectrum of three-dimensional Landau operator perturbed by a periodic point potential
International Nuclear Information System (INIS)
Geiler, V.A.; Demidov, V.V.
1995-01-01
A study is made of a three-dimensional Schrodinger operator with magnetic field and perturbed by a periodic sum of zero-range potentials. In the case of a rational flux, the explicit form of the decomposition of the resolvent of this operator with respect to the spectrum of irreducible representations of the group of magnetic translations is found. In the case of integer flux, the explicit form of the dispersion laws is found, the spectrum is described, and a qualitative investigation of it is made (in particular, it is established that not more than one gap exists)
International Nuclear Information System (INIS)
Abbagari, Souleymanou; Bouetou, Thomas B.; Kofane, Timoleon C.
2013-01-01
The prolongation structure methodologies of Wahlquist—Estabrook [H.D. Wahlquist and F.B. Estabrook, J. Math. Phys. 16 (1975) 1] for nonlinear differential equations are applied to a more general set of coupled integrable dispersionless system. Based on the obtained prolongation structure, a Lie-Algebra valued connection of a closed ideal of exterior differential forms related to the above system is constructed. A Lie-Algebra representation of some hidden structural symmetries of the previous system, its Bäcklund transformation using the Riccati form of the linear eigenvalue problem and their general corresponding Lax-representation are derived. In the wake of the previous results, we extend the above prolongation scheme to higher-dimensional systems from which a new (2 + 1)-dimensional coupled integrable dispersionless system is unveiled along with its inverse scattering formulation, which applications are straightforward in nonlinear optics where additional propagating dimension deserves some attention. (general)
Studying Operation Rules of Cascade Reservoirs Based on Multi-Dimensional Dynamics Programming
Directory of Open Access Journals (Sweden)
Zhiqiang Jiang
2017-12-01
Full Text Available Although many optimization models and methods are applied to the optimization of reservoir operation at present, the optimal operation decision that is made through these models and methods is just a retrospective review. Due to the limitation of hydrological prediction accuracy, it is practical and feasible to obtain the suboptimal or satisfactory solution by the established operation rules in the actual reservoir operation, especially for the mid- and long-term operation. In order to obtain the optimized sample data with global optimality; and make the extracted operation rules more reasonable and reliable, this paper presents the multi-dimensional dynamic programming model of the optimal joint operation of cascade reservoirs and provides the corresponding recursive equation and the specific solving steps. Taking Li Xianjiang cascade reservoirs as a case study, seven uncertain problems in the whole operation period of the cascade reservoirs are summarized after a detailed analysis to the obtained optimal sample data, and two sub-models are put forward to solve these uncertain problems. Finally, by dividing the whole operation period into four characteristic sections, this paper extracts the operation rules of each reservoir for each section respectively. When compared the simulation results of the extracted operation rules with the conventional joint operation method; the result indicates that the power generation of the obtained rules has a certain degree of improvement both in inspection years and typical years (i.e., wet year; normal year and dry year. So, the rationality and effectiveness of the extracted operation rules are verified by the comparative analysis.
A unidirectional approach for d-dimensional finite element methods for higher order on sparse grids
Energy Technology Data Exchange (ETDEWEB)
Bungartz, H.J. [Technische Universitaet Muenchen (Germany)
1996-12-31
In the last years, sparse grids have turned out to be a very interesting approach for the efficient iterative numerical solution of elliptic boundary value problems. In comparison to standard (full grid) discretization schemes, the number of grid points can be reduced significantly from O(N{sup d}) to O(N(log{sub 2}(N)){sup d-1}) in the d-dimensional case, whereas the accuracy of the approximation to the finite element solution is only slightly deteriorated: For piecewise d-linear basis functions, e. g., an accuracy of the order O(N{sup - 2}(log{sub 2}(N)){sup d-1}) with respect to the L{sub 2}-norm and of the order O(N{sup -1}) with respect to the energy norm has been shown. Furthermore, regular sparse grids can be extended in a very simple and natural manner to adaptive ones, which makes the hierarchical sparse grid concept applicable to problems that require adaptive grid refinement, too. An approach is presented for the Laplacian on a uinit domain in this paper.
Surface Casimir densities and induced cosmological constant in higher dimensional braneworlds
International Nuclear Information System (INIS)
Saharian, Aram A.
2006-01-01
We investigate the vacuum expectation value of the surface energy-momentum tensor for a massive scalar field with general curvature coupling parameter obeying the Robin boundary conditions on two codimension one parallel branes in a (D+1)-dimensional background spacetime AdS D 1 +1 xΣ with a warped internal space Σ. These vacuum densities correspond to a gravitational source of the cosmological constant type for both subspaces of the branes. Using the generalized zeta function technique in combination with contour integral representations, the surface energies on the branes are presented in the form of the sum of single-brane and second-brane-induced parts. For the geometry of a single brane both regions, on the left and on the right of the brane, are considered. At the physical point the corresponding zeta functions contain pole and finite contributions. For an infinitely thin brane taking these regions together, in odd spatial dimensions the pole parts cancel and the total zeta function is finite. The renormalization procedure for the surface energies and the structure of the corresponding counterterms are discussed. The parts in the surface densities generated by the presence of the second brane are finite for all nonzero values of the interbrane separation and are investigated in various asymptotic regions of the parameters. In particular, it is shown that for large distances between the branes the induced surface densities give rise to an exponentially suppressed cosmological constant on the brane. The total energy of the vacuum including the bulk and boundary contributions is evaluated by the zeta function technique and the energy balance between separate parts is discussed
Williams, Daniel M.; Consiglio, Maria C.; Murdoch, Jennifer L.; Adams, Catherine H.
2005-01-01
This paper provides an analysis of Flight Technical Error (FTE) from recent SATS experiments, called the Higher Volume Operations (HVO) Simulation and Flight experiments, which NASA conducted to determine pilot acceptability of the HVO concept for normal operating conditions. Reported are FTE results from simulation and flight experiment data indicating the SATS HVO concept is viable and acceptable to low-time instrument rated pilots when compared with today s system (baseline). Described is the comparative FTE analysis of lateral, vertical, and airspeed deviations from the baseline and SATS HVO experimental flight procedures. Based on FTE analysis, all evaluation subjects, low-time instrument-rated pilots, flew the HVO procedures safely and proficiently in comparison to today s system. In all cases, the results of the flight experiment validated the results of the simulation experiment and confirm the utility of the simulation platform for comparative Human in the Loop (HITL) studies of SATS HVO and Baseline operations.
Beyond Public and Private: A Framework for Co-operative Higher Education
Directory of Open Access Journals (Sweden)
Mike Neary
2017-07-01
Full Text Available Universities in the UK are increasingly adopting corporate governance structures, a consumerist model of teaching and learning, and have the most expensive tuition fees in the world (McGettigan, 2013; OECD, 2015. This article discusses collaborative research that aimed to develop and define a conceptual framework of knowledge production grounded in co-operative values and principles. The main findings are outlined relating to the key themes of our research: knowledge, democracy, bureaucracy, livelihood, and solidarity. We consider how these five ‘catalytic principles’ relate to three identified routes to co-operative higher education (conversion, dissolution, or creation and argue that such work must be grounded in an adequate critique of labour and property, i.e. the capital relation. We identify both the possible opportunities that the latest higher education reform in the UK affords the co-operative movement as well as the issues that arise from a more marketised and financialised approach to the production of knowledge (HEFCE, 2015. Finally, we suggest ways that the co-operative movement might respond with democratic alternatives that go beyond the distinction of public and private education.
Antibound states for a class of one-dimensional Schroedinger Operators
Energy Technology Data Exchange (ETDEWEB)
Angeletti, A [Camerino Univ. (Italy). Ist. di Matematica
1980-11-01
Let delta(x) be the Dirac's delta, q(x) element of L/sup 1/(R) L/sup 2/(R) be a real valued function, and lambda, ..mu.. element of R; we will consider the following class of one-dimensional formal Schroedinger operators on L/sup 2/(R) H(lambda,..mu..) = - (d/sup 2//dx/sup 2/) + lambdadelta(x) + ..mu..q(x). It is known that to the formal operator H(lambda, ..mu..) may be associated a selfadjoint operator H(lambda, ..mu..) on L/sup 2/(R). If q is of finite range, for lambda < 0 and /..mu../ is small enough, we prove that H(lambda,..mu..) has an antibound state; that is the resolvent of H(lambda,..mu..) has a pole on the negative real axis on the second Riemann sheet.
Antibound states for a class of one-dimensional Schroedinger Operators
International Nuclear Information System (INIS)
Angeletti, A.
1980-01-01
Let delta(x) be the Dirac's delta, q(x) element of L 1 (R) L 2 (R) be a real valued function, and lambda, μ element of R; we will consider the following class of one-dimensional formal Schroedinger operators on L 2 (R) H(lambda,μ) = - (d 2 /dx 2 ) + lambdadelta(x) + μq(x). It is known that to the formal operator H(lambda, μ) may be associated a selfadjoint operator H(lambda, μ) on L 2 (R). If q is of finite range, for lambda < 0 and /μ/ is small enough, we prove that H(lambda,μ) has an antibound state; that is the resolvent of H(lambda,μ) has a pole on the negative real axis on the second Riemann sheet. (orig.)
International Nuclear Information System (INIS)
Hall, M.L.; Davis, A.B.
2005-01-01
Accurate modeling of radiative energy transport through cloudy atmospheres is necessary for both climate modeling with GCMs (Global Climate Models) and remote sensing. Previous modeling efforts have taken advantage of extreme aspect ratios (cells that are very wide horizontally) by assuming a 1-D treatment vertically - the Independent Column Approximation (ICA). Recent attempts to resolve radiation transport through the clouds have drastically changed the aspect ratios of the cells, moving them closer to unity, such that the ICA model is no longer valid. We aim to provide a higher-fidelity atmospheric radiation transport model which increases accuracy while maintaining efficiency. To that end, this paper describes the development of an efficient 3-D-capable radiation code that can be easily integrated into cloud resolving models as an alternative to the resident 1-D model. Applications to test cases from the Intercomparison of 3-D Radiation Codes (I3RC) protocol are shown
Higher Dimensional Charged Black Hole Solutions in f(R Gravitational Theories
Directory of Open Access Journals (Sweden)
G. G. L. Nashed
2018-01-01
Full Text Available We present, without any assumption, a class of electric and magnetic flat horizon D-dimension solutions for a specific class of f(R=R+αR2, all of which behave asymptotically as Anti-de-Sitter spacetime. The most interesting property of these solutions is that the higher dimensions black holes, D>4, always have constant electric and magnetic charges in contrast to what is known in the literature. For D=4, we show that the magnetic field participates in the metric on equal foot as the electric field participates. Another interesting result is the fact that the Cauchy horizon is not identical with the event horizon. We use Komar formula to calculate the conserved quantities. We study the singularities and calculate the Hawking temperature and entropy and show that the first law of thermodynamics is always satisfied.
The phase structure of higher-dimensional black rings and black holes
International Nuclear Information System (INIS)
Emparan, Roberto; Harmark, Troels; Niarchos, Vasilis; Obers, Niels A.; RodrIguez, Maria J.
2007-01-01
We construct an approximate solution for an asymptotically flat, neutral, thin rotating black ring in any dimension D ≥ 5 by matching the near-horizon solution for a bent boosted black string, to a linearized gravity solution away from the horizon. The rotating black ring solution has a regular horizon of topology S 1 x S D-3 and incorporates the balancing condition of the ring as a zero-tension condition. For D = 5 our method reproduces the thin ring limit of the exact black ring solution. For D ≥ 6 we show that the black ring has a higher entropy than the Myers-Perry black hole in the ultra-spinning regime. By exploiting the correspondence between ultra-spinning black holes and black membranes on a two-torus, we take steps towards qualitatively completing the phase diagram of rotating blackfolds with a single angular momentum. We are led to propose a connection between MP black holes and black rings, and between MP black holes and black Saturns, through merger transitions involving two kinds of 'pinched' black holes. More generally, the analogy suggests an infinite number of pinched black holes of spherical topology leading to a complicated pattern of connections and mergers between phases
Fundamental and higher two-dimensional resonance modes of an Alpine valley
Ermert, Laura; Poggi, Valerio; Burjánek, Jan; Fäh, Donat
2014-08-01
We investigated the sequence of 2-D resonance modes of the sediment fill of Rhône Valley, Southern Swiss Alps, a strongly overdeepened, glacially carved basin with a sediment fill reaching a thickness of up to 900 m. From synchronous array recordings of ambient vibrations at six locations between Martigny and Sion we were able to identify several resonance modes, in particular, previously unmeasured higher modes. Data processing was performed with frequency domain decomposition of the cross-spectral density matrices of the recordings and with time-frequency dependent polarization analysis. 2-D finite element modal analysis was performed to support the interpretation of processing results and to investigate mode shapes at depth. In addition, several models of realistic bedrock geometries and velocity structures could be used to qualitatively assess the sensitivity of mode shape and particle motion dip angle to subsurface properties. The variability of modal characteristics due to subsurface properties makes an interpretation of the modes purely from surface observations challenging. We conclude that while a wealth of information on subsurface structure is contained in the modal characteristics, a careful strategy for their interpretation is needed to retrieve this information.
The Small Aircraft Transportation System (SATS), Higher Volume Operations (HVO) Concept and Research
Baxley, B.; Williams, D.; Consiglio, M.; Adams, C.; Abbott, T.
2005-01-01
The ability to conduct concurrent, multiple aircraft operations in poor weather at virtually any airport offers an important opportunity for a significant increase in the rate of flight operations, a major improvement in passenger convenience, and the potential to foster growth of operations at small airports. The Small Aircraft Transportation System, (SATS) Higher Volume Operations (HVO) concept is designed to increase capacity at the 3400 non-radar, non-towered airports in the United States where operations are currently restricted to one-in/one-out procedural separation during low visibility or ceilings. The concept s key feature is that pilots maintain their own separation from other aircraft using air-to-air datalink and on-board software within the Self-Controlled Area (SCA), an area of flight operations established during poor visibility and low ceilings around an airport without Air Traffic Control (ATC) services. While pilots self-separate within the SCA, an Airport Management Module (AMM) located at the airport assigns arriving pilots their sequence based on aircraft performance, position, winds, missed approach requirements, and ATC intent. The HVO design uses distributed decision-making, safe procedures, attempts to minimize pilot and controller workload, and integrates with today's ATC environment. The HVO procedures have pilots make their own flight path decisions when flying in Instrument Metrological Conditions (IMC) while meeting these requirements. This paper summarizes the HVO concept and procedures, presents a summary of the research conducted and results, and outlines areas where future HVO research is required. More information about SATS HVO can be found at http://ntrs.nasa.gov.
Lin, Mengquan; Chang, Kai; Gong, Le
2016-01-01
The higher education quality evaluation and assurance frameworks and their operating mechanisms of countries such as the United Kingdom, France, and the United States show that higher education systems, traditional culture, and social background all impact quality assurance operating mechanisms. A model analysis of these higher education quality…
The Integrity of ACSR Full Tension Single-Stage Splice Connector at Higher Operation Temperature
Energy Technology Data Exchange (ETDEWEB)
Wang, Jy-An John [ORNL; Lara-Curzio, Edgar [ORNL; King Jr, Thomas J [ORNL
2008-10-01
Due to increases in power demand and limited investment in new infrastructure, existing overhead power transmission lines often need to operate at temperatures higher than those used for the original design criteria. This has led to the accelerated aging and degradation of splice connectors. It is manifested by the formation of hot-spots that have been revealed by infrared imaging during inspection. The implications of connector aging is two-fold: (1) significant increases in resistivity of the splice connector (i.e., less efficient transmission of electricity) and (2) significant reductions in the connector clamping strength, which could ultimately result in separation of the power transmission line at the joint. Therefore, the splice connector appears to be the weakest link in electric power transmission lines. This report presents a protocol for integrating analytical and experimental approaches to evaluate the integrity of full tension single-stage splice connector assemblies and the associated effective lifetime at high operating temperature.
The spectrum of the periodic point perturbation of the three-dimensional Landau operator
International Nuclear Information System (INIS)
Gejler, V.A.; Demidov, V.V.
1995-01-01
The three-dimensional Schroedinger operator with magnetic field perturbated by the periodic sum of zero-range potentials is investigated. The explicit form of the decomposition of the resolnebt of the operator over the spectrum of the irreducible representations of the group of magnetic translations was found in the case of a rational flux. The explicit form of the dispersion laws was found, the description of the spectrum was given and the qualitative investigation of the spectrum was foun, the description of the spectrum was given and the qualitative of the spectrum was carried out in the case of an integer flux (in particular, it was found that there are no more than one gap). 30 refs
International Nuclear Information System (INIS)
Spinelly, J.; Mello, E.R. Bezerra de
2008-01-01
In this paper we investigate the vacuum polarization effects associated with quantum fermionic charged fields in a generalized (d+1)-dimensional cosmic string space-times considering the presence of a magnetic flux along the string. In order to develop this analysis we calculate a general expression for the respective Green function, valid for several different values of d, which is expressed in terms of a bispinor associated with the square of the Dirac operator. Adopting this result, we explicitly calculate the renormalized vacuum expectation values of the energy-momentum tensors, (T A B ) Ren. , associated with massless fields. Moreover, for specific values of the parameters which codify the cosmic string and the fractional part of the ratio of the magnetic flux by the quantum one, we were able to present in closed forms the bispinor and the respective Green function for massive fields.
Higgs-Yukawa model with higher dimension operators via extended mean field theory
Akerlund, Oscar
2016-01-01
Using Extended Mean Field Theory (EMFT) on the lattice, we study properties of the Higgs-Yukawa model as an approximation of the Standard Model Higgs sector, and the effect of higher dimension operators. We note that the discussion of vacuum stability is completely modified in the presence of a $\\phi^6$ term, and that the Higgs mass no longer appears fine tuned. We also study the finite temperature transition. Without higher dimension operators the transition is found to be second order (crossover with gauge fields) for the experimental value of the Higgs mass $M_h=125$ GeV. By taking a $\\phi^6$ interaction in the Higgs potential as a proxy for a UV completion of the Standard Model, the transition becomes stronger and turns first order if the scale of new physics, i.e. the mass of the lightest mediator particle, is around $1.5$ TeV. This implies that electroweak baryogenesis may be viable in models which introduce new particles around that scale.
Williams, Daniel; Consiglio, Maria; Murdoch, Jennifer; Adams, Catherine
2004-01-01
This document provides a preliminary validation of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept for normal conditions. Initial results reveal that the concept provides reduced air traffic delays when compared to current operations without increasing pilot workload. Characteristic to the SATS HVO concept is the establishment of a newly defined area of flight operations called a Self-Controlled Area (SCA) which would be activated by air traffic control (ATC) around designated non-towered, non-radar airports. During periods of poor visibility, SATS pilots would take responsibility for separation assurance between their aircraft and other similarly equipped aircraft in the SCA. Using onboard equipment and simple instrument flight procedures, they would then be better able to approach and land at the airport or depart from it. This concept would also require a new, ground-based automation system, typically located at the airport that would provide appropriate sequencing information to the arriving aircraft. Further validation of the SATS HVO concept is required and is the subject of ongoing research and subsequent publications.
Key processes shaping the current role and operation of higher education institutions in society
Directory of Open Access Journals (Sweden)
Piróg Danuta
2016-03-01
Full Text Available The concurrent processes of globalisation, computerisation, and integration shape and constantly modify developmental factors and generate multidirectional social changes. Among social life fields, one of them has been particularly sensitive to the impact of those processes and has remained in clear feedback relationship with them is education, including university-level education. This article aims to present some reflections on the key processes which influence the environment of higher education institutions’ activity and on what their impact specifically is. The factors taken into account include: the transformation of the political and economic system, integration with the European higher education area, the market shift of education, evolving social demands towards higher education institutions and society’s attitude towards work. As knowledge has become an asset largely affecting the quality of life of people and society, universities have changed their focus from searching for and exploring truth, good and beauty in the world towards becoming innovation centres, transferring knowledge as offering their educational services. In this article, those trends have been exemplified in relation to geography degree programmes, and shown through an evolution of the model of the university. Based on a review of the literature, it seems that the processes discussed also concern geography degree programmes, and the future operation of these programmes closely depends on whether they can maintain their care for high quality education coupled with genuine efforts to ensure the smooth transition of graduates into the labour market.
Energy Technology Data Exchange (ETDEWEB)
Lin Kai, E-mail: lk314159@126.co [Institute of Theoretical Physics, China West Normal University, NanChong, SiChuan 637002 (China); Yang Shuzheng, E-mail: szyangcwnu@126.co [Institute of Theoretical Physics, China West Normal University, NanChong, SiChuan 637002 (China)
2009-10-12
Applying the method beyond semiclassical approximation, fermion tunneling from higher-dimensional anti-de Sitter Schwarzschild black hole is researched. In our work, the 'tortoise' coordinate transformation is introduced to simplify Dirac equation, so that the equation proves that only the (r-t) sector is important to our research. Because we only need to study the (r-t) sector, the Dirac equation is decomposed into several pairs of equations spontaneously, and we then prove the components of wave functions are proportional to each other in every pair of equations. Therefore, the suitable action forms of the wave functions are obtained, and finally the correctional Hawking temperature and entropy can be determined via the method beyond semiclassical approximation.
Le Moal, Julien; Peillon, Christophe; Dacher, Jean-Nicolas; Baste, Jean-Marc
2018-01-01
The objective of our pilot study was to assess if three-dimensional (3D) reconstruction performed by Visible Patient™ could be helpful for the operative planning, efficiency and safety of robot-assisted segmentectomy. Between 2014 and 2015, 3D reconstructions were provided by the Visible Patient™ online service and used for the operative planning of robotic segmentectomy. To obtain 3D reconstruction, the surgeon uploaded the anonymized computed tomography (CT) image of the patient to the secured Visible Patient™ server and then downloaded the model after completion. Nine segmentectomies were performed between 2014 and 2015 using a pre-operative 3D model. All 3D reconstructions met our expectations: anatomical accuracy (bronchi, arteries, veins, tumor, and the thoracic wall with intercostal spaces), accurate delimitation of each segment in the lobe of interest, margin resection, free space rotation, portability (smartphone, tablet) and time saving technique. We have shown that operative planning by 3D CT using Visible Patient™ reconstruction is useful in our practice of robot-assisted segmentectomy. The main disadvantage is the high cost. Its impact on reducing complications and improving surgical efficiency is the object of an ongoing study.
Energy Technology Data Exchange (ETDEWEB)
Borges, L.H.C., E-mail: luizhenriqueunifei@yahoo.com.br [Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, SP, 09210-580 (Brazil); Dias, A.G., E-mail: alex.dias@ufabc.edu.br [Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, SP, 09210-580 (Brazil); Ferrari, A.F., E-mail: alysson.ferrari@ufabc.edu.br [Universidade Federal do ABC, Centro de Ciências Naturais e Humanas, Av. dos Estados, 5001, Santo André, SP, 09210-580 (Brazil); Nascimento, J.R., E-mail: jroberto@fisica.ufpb.br [Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, João Pessoa, Paraíba, 58051-970 (Brazil); Petrov, A.Yu., E-mail: petrov@fisica.ufpb.br [Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, João Pessoa, Paraíba, 58051-970 (Brazil)
2016-05-10
We study the perturbative generation of higher-derivative Lorentz violating operators as quantum corrections to the photon effective action, originated from a specific Lorentz violation background, which has already been studied in connection with the physics of light pseudoscalars. We calculate the complete one loop effective action of the photon field through the proper-time method, using the zeta function regularization. This result can be used as a starting point to study possible effects of the Lorentz violating background we are considering in photon physics. As an example, we focus on the lowest order corrections and investigate whether they could influence the propagation of electromagnetic waves through the vacuum. We show, however, that no effects of the kind of Lorentz violation we consider can be detected in such a context, so that other aspects of photon physics have to be studied.
Williams, Daniel M.
2006-01-01
Described is the research process that NASA researchers used to validate the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) concept. The four phase building-block validation and verification process included multiple elements ranging from formal analysis of HVO procedures to flight test, to full-system architecture prototype that was successfully shown to the public at the June 2005 SATS Technical Demonstration in Danville, VA. Presented are significant results of each of the four research phases that extend early results presented at ICAS 2004. HVO study results have been incorporated into the development of the Next Generation Air Transportation System (NGATS) vision and offer a validated concept to provide a significant portion of the 3X capacity improvement sought after in the United States National Airspace System (NAS).
International Nuclear Information System (INIS)
Nguyen Buong.
1992-11-01
The purpose of this paper is to investigate convergence rates for an operator version of Tikhonov regularization constructed by dual mapping for nonlinear ill-posed problems involving monotone operators in real reflective Banach spaces. The obtained results are considered in combination with finite-dimensional approximations for the space. An example is considered for illustration. (author). 15 refs
Higher-level fusion for military operations based on abductive inference: proof of principle
Pantaleev, Aleksandar V.; Josephson, John
2006-04-01
The ability of contemporary military commanders to estimate and understand complicated situations already suffers from information overload, and the situation can only grow worse. We describe a prototype application that uses abductive inferencing to fuse information from multiple sensors to evaluate the evidence for higher-level hypotheses that are close to the levels of abstraction needed for decision making (approximately JDL levels 2 and 3). Abductive inference (abduction, inference to the best explanation) is a pattern of reasoning that occurs naturally in diverse settings such as medical diagnosis, criminal investigations, scientific theory formation, and military intelligence analysis. Because abduction is part of common-sense reasoning, implementations of it can produce reasoning traces that are very human understandable. Automated abductive inferencing can be deployed to augment human reasoning, taking advantage of computation to process large amounts of information, and to bypass limits to human attention and short-term memory. We illustrate the workings of the prototype system by describing an example of its use for small-unit military operations in an urban setting. Knowledge was encoded as it might be captured prior to engagement from a standard military decision making process (MDMP) and analysis of commander's priority intelligence requirements (PIR). The system is able to reasonably estimate the evidence for higher-level hypotheses based on information from multiple sensors. Its inference processes can be examined closely to verify correctness. Decision makers can override conclusions at any level and changes will propagate appropriately.
Discrete SLn-connections and self-adjoint difference operators on 2-dimensional manifolds
International Nuclear Information System (INIS)
Grinevich, P G; Novikov, S P
2013-01-01
The programme of discretization of famous completely integrable systems and associated linear operators was launched in the 1990s. In particular, the properties of second-order difference operators on triangulated manifolds and equilateral triangular lattices have been studied by Novikov and Dynnikov since 1996. This study included Laplace transformations, new discretizations of complex analysis, and new discretizations of GL n -connections on triangulated n-dimensional manifolds. A general theory of discrete GL n -connections 'of rank one' has been developed (see the Introduction for definitions). The problem of distinguishing the subclass of SL n -connections (and unimodular SL n ± -connections, which satisfy detA = ±1) has not been solved. In the present paper it is shown that these connections play an important role (which is similar to the role of magnetic fields in the continuous case) in the theory of self-adjoint Schrödinger difference operators on equilateral triangular lattices in ℝ 2 . In Appendix 1 a complete characterization is given of unimodular SL n ± -connections of rank 1 for all n > 1, thus correcting a mistake (it was wrongly claimed that they reduce to a canonical connection for n > 2). With the help of a communication from Korepanov, a complete clarification is provided of how the classical theory of electrical circuits and star-triangle transformations is connected with the discrete Laplace transformations on triangular lattices. Bibliography: 29 titles
Color Image Encryption Using Three-Dimensional Sine ICMIC Modulation Map and DNA Sequence Operations
Liu, Wenhao; Sun, Kehui; He, Yi; Yu, Mengyao
Derived from Sine map and iterative chaotic map with infinite collapse (ICMIC), a three-dimensional hyperchaotic Sine ICMIC modulation map (3D-SIMM) is proposed based on a close-loop modulation coupling (CMC) method. Based on this map, a novel color image encryption algorithm is designed by employing a hybrid model of multidirectional circular permutation and deoxyribonucleic acid (DNA) masking. In this scheme, the pixel positions of image are scrambled by multidirectional circular permutation, and the pixel values are substituted by DNA sequence operations. The simulation results and security analysis show that the algorithm has good encryption effect and strong key sensitivity, and can resist brute-force, statistical, differential, known-plaintext and chosen-plaintext attacks.
International Nuclear Information System (INIS)
Lubuma, M.S.
1991-05-01
The applicability of the Neumann indirect method of potentials to the Dirichlet and Neumann problems for the two-dimensional Stokes operator on a non smooth boundary Γ is subject to two kinds of sufficient and/or necessary conditions on Γ. The first one, occurring in electrostatic, is equivalent to the boundedness on C(Γ) of the velocity double layer potential W as well as to the existence of jump relations of potentials. The second condition, which forces Γ to be a simple rectifiable curve and which, compared to the Laplacian, is a stronger restriction on the corners of Γ, states that the Fredholm radius of W is greater than 2. Under these conditions, the Radon boundary integral equations defined by the above mentioned jump relations are solvable by the Fredholm theory; the double (for Dirichlet) and the single (for Neumann) layer potentials corresponding to their solutions are classical solutions of the Stokes problems. (author). 48 refs
On the number of eigenvalues of the discrete one-dimensional Dirac operator with a complex potential
Hulko, Artem
2018-03-01
In this paper we define a one-dimensional discrete Dirac operator on Z . We study the eigenvalues of the Dirac operator with a complex potential. We obtain bounds on the total number of eigenvalues in the case where V decays exponentially at infinity. We also estimate the number of eigenvalues for the discrete Schrödinger operator with complex potential on Z . That is we extend the result obtained by Hulko (Bull Math Sci, to appear) to the whole Z.
Directory of Open Access Journals (Sweden)
Lulu Wang
2016-01-01
Full Text Available A two-dimensional, single-phase, isothermal, multicomponent, transient model is built to investigate the transport phenomena in unitized regenerative fuel cells (URFCs under the condition of switching from the fuel cell (FC mode to the water electrolysis (WE mode. The model is coupled with an electrochemical reaction. The proton exchange membrane (PEM is selected as the solid electrolyte of the URFC. The work is motivated by the need to elucidate the complex mass transfer and electrochemical process under operation mode switching in order to improve the performance of PEM URFC. A set of governing equations, including conservation of mass, momentum, species, and charge, are considered. These equations are solved by the finite element method. The simulation results indicate the distributions of hydrogen, oxygen, water mass fraction, and electrolyte potential response to the transient phenomena via saltation under operation mode switching. The hydrogen mass fraction gradients are smaller than the oxygen mass fraction gradients. The average mass fractions of the reactants (oxygen and hydrogen and product (water exhibit evident differences between each layer in the steady state of the FC mode. By contrast, the average mass fractions of the reactant (water and products (oxygen and hydrogen exhibit only slight differences between each layer in the steady state of the WE mode. Under either the FC mode or the WE mode, the duration of the transient state is only approximately 0.2 s.
Two-dimensional optoelectronic interconnect-processor and its operational bit error rate
Liu, J. Jiang; Gollsneider, Brian; Chang, Wayne H.; Carhart, Gary W.; Vorontsov, Mikhail A.; Simonis, George J.; Shoop, Barry L.
2004-10-01
Two-dimensional (2-D) multi-channel 8x8 optical interconnect and processor system were designed and developed using complementary metal-oxide-semiconductor (CMOS) driven 850-nm vertical-cavity surface-emitting laser (VCSEL) arrays and the photodetector (PD) arrays with corresponding wavelengths. We performed operation and bit-error-rate (BER) analysis on this free-space integrated 8x8 VCSEL optical interconnects driven by silicon-on-sapphire (SOS) circuits. Pseudo-random bit stream (PRBS) data sequence was used in operation of the interconnects. Eye diagrams were measured from individual channels and analyzed using a digital oscilloscope at data rates from 155 Mb/s to 1.5 Gb/s. Using a statistical model of Gaussian distribution for the random noise in the transmission, we developed a method to compute the BER instantaneously with the digital eye-diagrams. Direct measurements on this interconnects were also taken on a standard BER tester for verification. We found that the results of two methods were in the same order and within 50% accuracy. The integrated interconnects were investigated in an optoelectronic processing architecture of digital halftoning image processor. Error diffusion networks implemented by the inherently parallel nature of photonics promise to provide high quality digital halftoned images.
Perturbation theory of low-dimensional quantum liquids. I. The pseudoparticle-operator basis
International Nuclear Information System (INIS)
Carmelo, J.M.P.; Castro Neto, A.H.; Campbell, D.K.
1994-01-01
We introduce an operator algebra for the description of the low-energy physics of one-dimensional, integrable, multicomponent quantum liquids. Considering the particular case of the Hubbard chain in a magnetic field and chemical potential, we show that at low energy its Bethe-ansatz solution can be interpreted in terms of a pseudoparticle-operator algebra. Our algebraic approach provides a concise interpretation of, and justification for, several recent studies of low-energy excitations and trasnport which have been based on detailed analyses of specific Bethe-ansatz eigenfunctions and eigenenergies. A central point is that the exact ground state of the interacting many-electron problem is the noninteracting pseudoparticle ground state. Furthermore, in the pseudoparticle basis, the quantum problem becomes perturbative, i.e., the two-pseudoparticle forward-scattering vertices and amplitudes do not diverge, and one can define a many-pseudoparticle perturbation theory. We write the general quantum-liquid Hamiltonian in the pseudoparticle basis and show that the pseudoparticle-perturbation theory leads, in a natural way, to the generalized Landau-liquid approach
Institute of Scientific and Technical Information of China (English)
XU Dian-Yan
2003-01-01
The free energy and entropy of Reissner-Nordstrom black holes in higher-dimensional space-time are calculated by the quantum statistic method with a brick wall model. The space-time of the black holes is divided into three regions: region 1, (r > r0); region 2, (r0 > r > n); and region 3, (T-J > r > 0), where r0 is the radius of the outer event horizon, and r, is the radius of the inner event horizon. Detailed calculation shows that the entropy contributed by region 2 is zero, the entropy contributed by region 1 is positive and proportional to the outer event horizon area, the entropy contributed by region 3 is negative and proportional to the inner event horizon area. The total entropy contributed by all the three regions is positive and proportional to the area difference between the outer and inner event horizons. As rt approaches r0 in the nearly extreme case, the total quantum statistical entropy approaches zero.
Energy Technology Data Exchange (ETDEWEB)
Furuuchi, Kazuyuki [Manipal Centre for Natural Sciences, Manipal University,Manipal, Karnataka 576104 (India); Koyama, Yoji [National Center for Theoretical Sciences, National Tsing-Hua University,Hsinchu 30013, Taiwan R.O.C. (China)
2016-06-21
We continue our investigation of large field inflation models obtained from higher-dimensional gauge theories, initiated in our previous study http://dx.doi.org/10.1088/1475-7516/2015/02/031. We focus on Dante’s Inferno model which was the most preferred model in our previous analysis. We point out the relevance of the IR obstruction to UV completion, which constrains the form of the potential of the massive vector field, under the current observational upper bound on the tensor to scalar ratio. We also show that in simple examples of the potential arising from DBI action of a D5-brane and that of an NS5-brane that the inflation takes place in the field range which is within the convergence radius of the Taylor expansion. This is in contrast to the well known examples of axion monodromy inflation where inflaton takes place outside the convergence radius of the Taylor expansion. This difference arises from the very essence of Dante’s Inferno model that the effective inflaton potential is stretched in the inflaton field direction compared with the potential for the original field.
International Nuclear Information System (INIS)
Furuuchi, Kazuyuki; Koyama, Yoji
2016-01-01
We continue our investigation of large field inflation models obtained from higher-dimensional gauge theories, initiated in our previous study http://dx.doi.org/10.1088/1475-7516/2015/02/031. We focus on Dante’s Inferno model which was the most preferred model in our previous analysis. We point out the relevance of the IR obstruction to UV completion, which constrains the form of the potential of the massive vector field, under the current observational upper bound on the tensor to scalar ratio. We also show that in simple examples of the potential arising from DBI action of a D5-brane and that of an NS5-brane that the inflation takes place in the field range which is within the convergence radius of the Taylor expansion. This is in contrast to the well known examples of axion monodromy inflation where inflaton takes place outside the convergence radius of the Taylor expansion. This difference arises from the very essence of Dante’s Inferno model that the effective inflaton potential is stretched in the inflaton field direction compared with the potential for the original field.
Exploration of one-dimensional plasma current density profile for K-DEMO steady-state operation
Energy Technology Data Exchange (ETDEWEB)
Kang, J.S. [Seoul National University, Seoul 151-742 (Korea, Republic of); Jung, L. [National Fusion Research Institute, Daejeon (Korea, Republic of); Byun, C.-S.; Na, D.H.; Na, Y.-S. [Seoul National University, Seoul 151-742 (Korea, Republic of); Hwang, Y.S., E-mail: yhwang@snu.ac.kr [Seoul National University, Seoul 151-742 (Korea, Republic of)
2016-11-01
Highlights: • One-dimensional current density and its optimization for the K-DEMO are explored. • Plasma current density profile is calculated with an integrated simulation code. • The impact of self and external heating profiles is considered self-consistently. • Current density is identified as a reference profile by minimizing heating power. - Abstract: Concept study for Korean demonstration fusion reactor (K-DEMO) is in progress, and basic design parameters are proposed by targeting high magnetic field operation with ITER-sized machine. High magnetic field operation is a favorable approach to enlarge relative plasma performance without increasing normalized beta or plasma current. Exploration of one-dimensional current density profile and its optimization process for the K-DEMO steady-state operation are reported in this paper. Numerical analysis is conducted with an integrated plasma simulation code package incorporating a transport code with equilibrium and current drive modules. Operation regimes are addressed with zero-dimensional system analysis. One-dimensional plasma current density profile is calculated based on equilibrium, bootstrap current analysis, and thermal transport analysis. The impact of self and external heating profiles on those parameters is considered self-consistently, where thermal power balance and 100% non-inductive current drive are the main constraints during the whole exploration procedure. Current and pressure profiles are identified as a reference steady-state profile by minimizing the external heating power with desired fusion power.
Ma, Q.; Boulet, C.; Tipping, R. H.
2014-01-01
The refinement of the Robert-Bonamy (RB) formalism by considering the line coupling for isotropic Raman Q lines of linear molecules developed in our previous study [Q. Ma, C. Boulet, and R. H. Tipping, J. Chem. Phys. 139, 034305 (2013)] has been extended to infrared P and R lines. In these calculations, the main task is to derive diagonal and off-diagonal matrix elements of the Liouville operator iS1 - S2 introduced in the formalism. When one considers the line coupling for isotropic Raman Q lines where their initial and final rotational quantum numbers are identical, the derivations of off-diagonal elements do not require extra correlation functions of the ^S operator and their Fourier transforms except for those used in deriving diagonal elements. In contrast, the derivations for infrared P and R lines become more difficult because they require a lot of new correlation functions and their Fourier transforms. By introducing two dimensional correlation functions labeled by two tensor ranks and making variable changes to become even functions, the derivations only require the latters' two dimensional Fourier transforms evaluated at two modulation frequencies characterizing the averaged energy gap and the frequency detuning between the two coupled transitions. With the coordinate representation, it is easy to accurately derive these two dimensional correlation functions. Meanwhile, by using the sampling theory one is able to effectively evaluate their two dimensional Fourier transforms. Thus, the obstacles in considering the line coupling for P and R lines have been overcome. Numerical calculations have been carried out for the half-widths of both the isotropic Raman Q lines and the infrared P and R lines of C2H2 broadened by N2. In comparison with values derived from the RB formalism, new calculated values are significantly reduced and become closer to measurements.
An n-dimensional pseudo-differential operator involving the Hankel ...
Indian Academy of Sciences (India)
dimensional Hankel transformation is defined. The symbol class H m is introduced. It is shown that p.d.o.'s associated with symbols belonging to this class are continuous linear mappings of the -dimensional Zemanian space H ( I n ) into itself.
Energy Technology Data Exchange (ETDEWEB)
Franck, John M.; Chandrasekaran, Siddarth; Dzikovski, Boris; Dunnam, Curt R.; Freed, Jack H., E-mail: jhf3@cornell.edu [Department of Chemistry and Chemical Biology and National Biomedical Center for Advanced ESR Technology, Cornell University, Ithaca, New York 14853 (United States)
2015-06-07
The development, applications, and current challenges of the pulsed ESR technique of two-dimensional Electron-Electron Double Resonance (2D ELDOR) are described. This is a three-pulse technique akin to 2D Exchange Nuclear Magnetic Resonance, but involving electron spins, usually in the form of spin-probes or spin-labels. As a result, it required the extension to much higher frequencies, i.e., microwaves, and much faster time scales, with π/2 pulses in the 2-3 ns range. It has proven very useful for studying molecular dynamics in complex fluids, and spectral results can be explained by fitting theoretical models (also described) that provide a detailed analysis of the molecular dynamics and structure. We discuss concepts that also appear in other forms of 2D spectroscopy but emphasize the unique advantages and difficulties that are intrinsic to ESR. Advantages include the ability to tune the resonance frequency, in order to probe different motional ranges, while challenges include the high ratio of the detection dead time vs. the relaxation times. We review several important 2D ELDOR studies of molecular dynamics. (1) The results from a spin probe dissolved in a liquid crystal are followed throughout the isotropic → nematic → liquid-like smectic → solid-like smectic → crystalline phases as the temperature is reduced and are interpreted in terms of the slowly relaxing local structure model. Here, the labeled molecule is undergoing overall motion in the macroscopically aligned sample, as well as responding to local site fluctuations. (2) Several examples involving model phospholipid membranes are provided, including the dynamic structural characterization of the boundary lipid that coats a transmembrane peptide dimer. Additionally, subtle differences can be elicited for the phospholipid membrane phases: liquid disordered, liquid ordered, and gel, and the subtle effects upon the membrane, of antigen cross-linking of receptors on the surface of plasma membrane
International Nuclear Information System (INIS)
Franck, John M.; Chandrasekaran, Siddarth; Dzikovski, Boris; Dunnam, Curt R.; Freed, Jack H.
2015-01-01
The development, applications, and current challenges of the pulsed ESR technique of two-dimensional Electron-Electron Double Resonance (2D ELDOR) are described. This is a three-pulse technique akin to 2D Exchange Nuclear Magnetic Resonance, but involving electron spins, usually in the form of spin-probes or spin-labels. As a result, it required the extension to much higher frequencies, i.e., microwaves, and much faster time scales, with π/2 pulses in the 2-3 ns range. It has proven very useful for studying molecular dynamics in complex fluids, and spectral results can be explained by fitting theoretical models (also described) that provide a detailed analysis of the molecular dynamics and structure. We discuss concepts that also appear in other forms of 2D spectroscopy but emphasize the unique advantages and difficulties that are intrinsic to ESR. Advantages include the ability to tune the resonance frequency, in order to probe different motional ranges, while challenges include the high ratio of the detection dead time vs. the relaxation times. We review several important 2D ELDOR studies of molecular dynamics. (1) The results from a spin probe dissolved in a liquid crystal are followed throughout the isotropic → nematic → liquid-like smectic → solid-like smectic → crystalline phases as the temperature is reduced and are interpreted in terms of the slowly relaxing local structure model. Here, the labeled molecule is undergoing overall motion in the macroscopically aligned sample, as well as responding to local site fluctuations. (2) Several examples involving model phospholipid membranes are provided, including the dynamic structural characterization of the boundary lipid that coats a transmembrane peptide dimer. Additionally, subtle differences can be elicited for the phospholipid membrane phases: liquid disordered, liquid ordered, and gel, and the subtle effects upon the membrane, of antigen cross-linking of receptors on the surface of plasma membrane
International Nuclear Information System (INIS)
Ryttov, Thomas A.; Sannino, Francesco
2007-01-01
We present the conformal windows of SU(N) supersymmetric and nonsupersymmetric gauge theories with vectorlike matter transforming according to higher irreducible representations of the gauge group. We determine the fraction of asymptotically free theories expected to develop an infrared fixed point and find that it does not depend on the specific choice of the representation. This result is exact in supersymmetric theories while it is an approximate one in the nonsupersymmetric case. The analysis allows us to size the unparticle world related to the existence of underlying gauge theories developing an infrared stable fixed point. We find that exactly 50% of the asymptotically free theories can develop an infrared fixed point while for the nonsupersymmetric theories it is circa 25%. When considering multiple representations, only for the nonsupersymmetric case, the conformal regions quickly dominate over the nonconformal ones. For four representations, 70% of the asymptotically free space is filled by the conformal region. According to our theoretical landscape survey the unparticle physics world occupies a sizable amount of the particle world, at least in theory space, and before mixing it (at the operator level) with the nonconformal one
Kneading determinants and spectra of transfer operators in higher dimensions, the isotropic case
Baillif, M
2003-01-01
Transfer operators M_k acting on k-forms in R^n are associated to smooth transversal local diffeomorphisms and compactly supported weight functions. A formal trace is defined by summing the product of the weight and the Lefschetz sign over all fixed points of all the diffeos. This yields a formal Ruelle-Lefschetz determinant Det^#(1-zM). We use the Milnor-Ruelle-Kitaev equality (recently proved by Baillif), which expressed Det^#(1-zM) as an alternated product of determinants of kneading operators, Det(1+D_k(z)), to relate zeroes and poles of the Ruelle-Lefschetz determinant to the spectra of the transfer operators M_k. As an application, we get a new proof of a theorem of Ruelle on smooth expanding dynamics.
The Effective Lifetime of ACSR Full Tension Splice Connector Operated at Higher Temperature
International Nuclear Information System (INIS)
Wang, Jy-An John; Lara-Curzio, Edgar; King Jr, Thomas J.; Graziano, Joe; Chan, John; Goodwin, Tip
2009-01-01
This paper is to address the issues related to integrity of ACSR full tension splice connectors operated at high temperatures. A protocol of integrating analytical and experimental approaches to evaluate the integrity of a full tension single-stage splice connector (SSC) assembly during service at high operating temperature was developed. Based on the developed protocol the effective lifetime evaluation was demonstrated with ACSR Drake conductor SSC systems. The investigation indicates that thermal cycling temperature and frequency, conductor cable tension loading, and the compressive residual stress field within a SSC system have significant impact on the SSC integrity and the associated effective lifetime
Directory of Open Access Journals (Sweden)
Abdel-Ouahab Boudraa
2005-10-01
Full Text Available In white-light interference microscopy, measurement of surface shape generally requires peak extraction of the fringe function envelope. In this paper the Teager-Kaiser energy and higher-order energy operators are proposed for efficient extraction of the fringe envelope. These energy operators are compared in terms of precision, robustness to noise, and subsampling. Flexible energy operators, depending on order and lag parameters, can be obtained. Results show that smoothing and interpolation of envelope approximation using spline model performs better than Gaussian-based approach.
Park, Ko Un; Nathanson, David
2017-08-01
Pre-operative measurements from the skin to a wire-localized breast lesion can differ from operating room measurements. This study was designed to measure the discrepancies and study factors that may contribute to wire movement. Prospective data were collected on patients who underwent wire localization lumpectomy. Clip and hook location, breast size, density, and direction of wire placement were the main focus of the analysis. Wire movement was more likely with longer distance from skin to hook or clip, larger breast size (especially if "fatty"), longer time between wire placement and surgery start time, and medial wire placement in larger breast. Age, body mass index, presence of mass, malignant diagnosis, tumor grade, and clip distance to the chest wall were not associated with wire movement. A longer distance from skin to hook correlated with larger specimen volume. Translation of the lesion location from a 2-dimensional mammogram into 3-dimensional breasts is sometimes discrepant because of movement of the localizing wire. Breast size, distance of skin to clip or hook, and wire exit site in larger breasts have a significant impact on wire movement. This information may guide the surgeon's skin incision and extent of excision. © 2017 Wiley Periodicals, Inc.
Guide for Developing High-Quality Emergency Operations Plans for Institutions of Higher Education
Office of Safe and Healthy Students, US Department of Education, 2013
2013-01-01
Our nation's postsecondary institutions are entrusted to provide a safe and healthy learning environment for students, faculty, and staff who live, work, and study on campus. Many of these emergencies occur with little to no warning; therefore, it is critical for institutions of higher education (IHEs) to plan ahead to help ensure the safety and…
Physical States and BRST Operators for Higher-spin $W$ Strings
Liu, Yu-Xiao; Wei, Shao-Wen; Zhang, Li-Jie; Ren, Ji-Rong
2008-01-01
In this paper, we mainly investigate the $W_{2,s}^{M}\\otimes W_{2,s}^{L}$ system, in which the matter and the Liouville subsystems generate $W_{2,s}^{M}$ and $W_{2,s}^L$ algebras respectively. We first give a brief discussion of the physical states for corresponding $W$ stings. The lower states are given by freezing the spin-2 and spin-$s$ currents. Then, introducing two pairs of ghost-like fields, we give the realizations of $W_{1,2,s}$ algebras. Based on these linear realizations, BRST oper...
The Lifetime Estimate for ACSR Single-Stage Splice Connector Operating at Higher Temperatures
International Nuclear Information System (INIS)
Wang, Jy-An John; Graziano, Joe; Chan, John
2011-01-01
This paper is the continuation of Part I effort to develop a protocol of integrating analytical and experimental approaches to evaluate the integrity of a full tension single-stage splice connector (SSC) assembly during service at high operating temperature.1The Part II efforts are mainly focused on the thermal mechanical testing, thermal-cycling simulation and its impact on the effective lifetime of the SSC system. The investigation indicates that thermal cycling temperature and frequency, conductor cable tension loading, and the compressive residual stress field within a SSC system have significant impact on the SSC integrity and the associated effective lifetime.
Energy Technology Data Exchange (ETDEWEB)
Li, Huai-Fan; Zhao, Hui-Hua; Zhang, Li-Chun; Zhao, Ren [Shanxi Datong University, Institute of Theoretical Physics, Datong (China); Shanxi Datong University, Department of Physics, Datong (China)
2017-05-15
Using Maxwell's equal area law, we discuss the phase transition of higher dimensional charged topological dilaton AdS black hole with a nonlinear source. The coexisting region of the two phases is found and we depict the coexistence region in the P-v diagrams. The two-phase equilibrium curves in the P-T diagrams are plotted, and we take the first order approximation of volume v in the calculation. To better compare with a general thermodynamic system, the Clapeyron equation is derived for a higher dimensional charged topological black hole with a nonlinear source. The latent heat of an isothermal phase transition is investigated. We also study the effect of the parameters of the black hole on the region of two-phase coexistence. The results show that the black hole may go through a small-large phase transition similar to those of usual non-gravity thermodynamic systems. (orig.)
Directory of Open Access Journals (Sweden)
V. N. Chetverikov
2014-01-01
Full Text Available Invertible linear differential operators with one independent variable are investigated. The problem of description of such operators is important, because it is connected with transformations and the classification of control systems, in particular, with the flatness problem.Each invertible linear differential operator represents a square matrix of scalar differential operators. Its product with an operator-column is an operator-column whose order does not exceed the sum of orders of initial operators. The operators-columns, the product with which leads to order fall, i.e. the order of the product is less than sum of orders of factors, are interesting for the description of invertible operators. In this paper the classification of invertible operators is based on dimensions dk,p of intersections of modules Gp and Fk for various k and p, where Gp is the module of all operators-columns of order not above p, and Fk is the module of compositions of the invertible operator with all operators-columns of order not above k. The invertible operators that have identical sets of numbers dk,p form one class.In the paper the general properties of tables of numbers dk,p for invertible operators are investigated. A correspondence between invertible operators and elementary-geometrical models which in the paper are named by d-schemes of squares is constructed. The invertible operator is ambiguously defined by its d-scheme of squares. The mathematical structure that must be set for its unique definition and an algorithm for the construction of the invertible operator are offered.In the proof of the main result, methods of the theory of chain complexes and their spectral sequences are used. In the paper all necessary concepts of this theory are formulated and the corresponding facts are proved.Results of the paper can be used for solving problems in which invertible linear differential operators are arisen. Namely, it is necessary to formulate the conditions on
International Nuclear Information System (INIS)
Nariai, Hidekazu; Ishihara, Hideki.
1983-01-01
Various geometrical properties of Nariai's less-familiar solution of the vacuum Einstein equations R sub( mu nu ) = lambda g sub( mu nu ) is f irst summarized in comparison with de Sitter's well-known solution. Next an extension of both solutions is performed in a six-dimensional space on the supposition that such an extension will in future become useful to elucidate more closely the creation of particles in an inflationary stage of the big-bang universe. For preparation, the behavior of a massive scalar field in the extended space-time is studied in a classical level. (author)
Physical states and BRST operators for higher-spin W strings
International Nuclear Information System (INIS)
Liu, Yu-Xiao; Wei, Shao-Wen; Ren, Ji-Rong; Zhang, Li-Jie
2009-01-01
In this paper, we mainly investigate the W 2,s M x W 2,s L system, in which the matter and the Liouville subsystems generate the W 2,s M and W 2,s L algebras, respectively. We first give a brief discussion of the physical states for the corresponding W strings. The lower states are given by freezing the spin-2 and spin-s currents. Then, introducing two pairs of ghost-like fields, we give the realizations of the W 1,2,s algebras. Based on these linear realizations, the BRST operators for the W 2,s algebras are obtained. Finally, we construct new BRST charges of the Liouville system for the W 2,s L strings at the specific values of the central charges c: c=-(22)/(5) for the W 2,3 L algebra, c=-24 for the W 2,4 L algebra and c=-2,-(286)/(3) for the W 2,6 L algebra, at which the corresponding W 2,s L algebras are singular. (orig.)
Ferdosi, Bilkis J.; Buddelmeijer, Hugo; Trager, Scott; Wilkinson, Michael H.F.; Roerdink, Jos B.T.M.
2010-01-01
Data sets in astronomy are growing to enormous sizes. Modern astronomical surveys provide not only image data but also catalogues of millions of objects (stars, galaxies), each object with hundreds of associated parameters. Exploration of this very high-dimensional data space poses a huge challenge.
Current status of three-dimensional silicon photonic crystals operating at infrared wavelengths
Energy Technology Data Exchange (ETDEWEB)
LIN,SHAWN-YU; FLEMING,JAMES G.; SIGALAS,M.M.; BISWAS,R.; HO,K.M.
2000-05-11
In this paper, the experimental realization and promises of three-dimensional (3D) photonic crystals in the infrared and optical wavelengths will be described. Emphasis will be placed on the development of new 3D photonic crystals, the micro- and nano-fabrication techniques, the construction of high-Q micro-cavities and the creation of 3D waveguides.
Poole, Dana S; Plenge, Esben; Poot, Dirk H J; Lakke, Egbert A J F; Niessen, Wiro J; Meijering, Erik; van der Weerd, Louise
2014-07-01
The visualization of activity in mouse brain using inversion recovery spin echo (IR-SE) manganese-enhanced MRI (MEMRI) provides unique contrast, but suffers from poor resolution in the slice-encoding direction. Super-resolution reconstruction (SRR) is a resolution-enhancing post-processing technique in which multiple low-resolution slice stacks are combined into a single volume of high isotropic resolution using computational methods. In this study, we investigated, first, whether SRR can improve the three-dimensional resolution of IR-SE MEMRI in the slice selection direction, whilst maintaining or improving the contrast-to-noise ratio of the two-dimensional slice stacks. Second, the contrast-to-noise ratio of SRR IR-SE MEMRI was compared with a conventional three-dimensional gradient echo (GE) acquisition. Quantitative experiments were performed on a phantom containing compartments of various manganese concentrations. The results showed that, with comparable scan times, the signal-to-noise ratio of three-dimensional GE acquisition is higher than that of SRR IR-SE MEMRI. However, the contrast-to-noise ratio between different compartments can be superior with SRR IR-SE MEMRI, depending on the chosen inversion time. In vivo experiments were performed in mice receiving manganese using an implanted osmotic pump. The results showed that SRR works well as a resolution-enhancing technique in IR-SE MEMRI experiments. In addition, the SRR image also shows a number of brain structures that are more clearly discernible from the surrounding tissues than in three-dimensional GE acquisition, including a number of nuclei with specific higher brain functions, such as memory, stress, anxiety and reward behavior. Copyright © 2014 John Wiley & Sons, Ltd.
On the conformal higher spin unfolded equation for a three-dimensional self-interacting scalar field
Energy Technology Data Exchange (ETDEWEB)
Nilsson, Bengt E.W. [Fundamental Physics, Chalmers University of Technology,SE-412 96 Göteborg (Sweden)
2016-08-24
We propose field equations for the conformal higher spin system in three dimensions coupled to a conformal scalar field with a sixth order potential. Both the higher spin equation and the unfolded equation for the scalar field have source terms and are based on a conformal higher spin algebra which we treat as an expansion in multi-commutators. Explicit expressions for the source terms are suggested and subjected to some simple tests. We also discuss a cascading relation between the Chern-Simons action for the higher spin gauge theory and an action containing a term for each spin that generalizes the spin 2 Chern-Simons action in terms of the spin connection expressed in terms of the frame field. This cascading property is demonstrated in the free theory for spin 3 but should work also in the complete higher spin theory.
Gray, C F; Staff, R T; Redpath, T W; Needham, G; Renny, N M
2000-05-01
To calculate sinus and bone graft volumes and vertical bone heights from sequential magnetic resonance imaging (MRI) examinations in patients undergoing a sinus lift operation. MRI scans were obtained pre-operatively and at 10 days and 10 weeks post-operatively, using a 0.95 tesla MRI scanner and a three-dimensional (3D) magnetisation prepared, rapid acquisition gradient-echo (MP-RAGE) sequence. Estimates of the bone graft volumes required for a desired vertical bone height were made from the pre-operative MRI scan. Measurements of the graft volumes and bone heights actually achieved were made from the post-operative scans. The MRI appearance of the graft changed between the 10 day and 10 week scans. We have proposed a technique which has the potential to give the surgeon an estimate of the optimum volume of graft for the sinus lift operation from the pre-operative MRI scan alone and demonstrated its application in a single patient. Changes in the sequential MRI appearance of the graft are consistent with replacement of fluid by a matrix of trabecular bone.
Patel, Krunal; Budohoski, Karol P; Kenyon, Olivia R P; Barone, Damiano G; Santarius, Thomas; Kirollos, Ramez W; Mannion, Richard J; Trivedi, Rikin A
2018-04-02
Thoracic disc prolapses causing cord compression can be challenging. For compressive central disc protrusions, a posterior approach is not suitable due to an unacceptable level of cord manipulation. An anterolateral transthoracic approach provides direct access to the disc prolapse allowing for decompression without disturbing the spinal cord. In this video, we describe 2 cases of thoracic myelopathy from a compressive central thoracic disc prolapse. In both cases, informed consent was obtained. Despite similar radiological appearances of heavy calcification, intraoperatively significant differences can be encountered. We demonstrate different surgical strategies depending on the consistency of the disc and the adherence to the thecal sac. With adequate exposure and detachment from adjacent vertebral bodies, soft discs can be, in most instances, separated from the theca with minimal cord manipulation. On the other hand, largely calcified discs often present a significantly greater challenge and require thinning the disc capsule before removal. In cases with significant adherence to dura, in order to prevent cord injury or cerebrospinal fluid leak a thinned shell can be left, providing total detachment from adjacent vertebrae can be achieved. Postoperatively, the first patient, with a significantly calcified disc, developed a transient left leg weakness which recovered by 3-month follow-up. This video outlines the anatomical considerations and operative steps for a transthoracic approach to a central disc prolapse, whilst demonstrating that computed tomography appearances are not always indicative of potential operative difficulties.
International Nuclear Information System (INIS)
Akarsu, Özgür; Dereli, Tekin
2013-01-01
We present cosmological solutions for (1+3+n)-dimensional steady state universe in dilaton gravity with an arbitrary dilaton coupling constant w and exponential dilaton self-interaction potentials in the string frame. We focus particularly on the class in which the 3-space expands with a time varying deceleration parameter. We discuss the number of the internal dimensions and the value of the dilaton coupling constant to determine the cases that are consistent with the observed universe and the primordial nucleosynthesis. The 3-space starts with a decelerated expansion rate and evolves into accelerated expansion phase subject to the values of w and n, but ends with a Big Rip in all cases. We discuss the cosmological evolution in further detail for the cases w = 1 and w = ½ that permit exact solutions. We also comment on how the universe would be conceived by an observer in four dimensions who is unaware of the internal dimensions and thinks that the conventional general relativity is valid at cosmological scales
Akarsu, Özgür; Dereli, Tekin
2013-02-01
We present cosmological solutions for (1+3+n)-dimensional steady state universe in dilaton gravity with an arbitrary dilaton coupling constant w and exponential dilaton self-interaction potentials in the string frame. We focus particularly on the class in which the 3-space expands with a time varying deceleration parameter. We discuss the number of the internal dimensions and the value of the dilaton coupling constant to determine the cases that are consistent with the observed universe and the primordial nucleosynthesis. The 3-space starts with a decelerated expansion rate and evolves into accelerated expansion phase subject to the values of w and n, but ends with a Big Rip in all cases. We discuss the cosmological evolution in further detail for the cases w = 1 and w = ½ that permit exact solutions. We also comment on how the universe would be conceived by an observer in four dimensions who is unaware of the internal dimensions and thinks that the conventional general relativity is valid at cosmological scales.
Directory of Open Access Journals (Sweden)
Farhad A. Namin
2016-08-01
Full Text Available A rigorous method for obtaining the diffraction patterns of quasicrystals is presented. Diffraction patterns are an essential analytical tool in the study of quasicrystals, since they can be used to determine their photonic resonances. Previous methods for approximating the diffraction patterns of quasicrystals have relied on evaluating the Fourier transform of finite-sized super-lattices. Our approach, on the other hand, is exact in the sense that it is based on a technique that embeds quasicrystals into higher dimensional periodic hyper-lattices, thereby completely capturing the properties of the infinite structure. The periodicity of the unit cell in the higher dimensional space can be exploited to obtain the Fourier series expansion in closed-form of the corresponding atomic surfaces. The utility of the method is demonstrated by applying it to one-dimensional Fibonacci and two-dimensional Penrose quasicrystals. The results are verified by comparing them to those obtained by using the conventional super-lattice method. It is shown that the conventional super-cell approach can lead to inaccurate results due to the continuous nature of the Fourier transform, since quasicrystals have a discrete spectrum, whereas the approach introduced in this paper generates discrete Fourier harmonics. Furthermore, the conventional approach requires very large super-cells and high-resolution sampling of the reciprocal space in order to produce accurate results leading to a very large computational burden, whereas the proposed method generates accurate results with a relatively small number of terms. Finally, we propose how this approach can be generalized from the vertex model, which assumes identical particles at all vertices, to a more realistic case where the quasicrystal is composed of different atoms.
Miyamoto, K.; Hoshino, T.; Hitotsubashi, R.; Yamashita, M.; Ueda, J.
In STS-95 space experiments, etiolated pea seedlings grown under microgravity conditions in space have shown to be automorphosis. Epicotyls were almost straight but the most oriented toward the direction far from their cotyledons with ca. 45 degrees from the vertical line as compared with that on earth. In order to know the mechanism of microgravity conditions in space to induce automorphosis, we introduced simulated microgravity conditions on a 3-dimensional clinostat, resulting in the successful induction of automorphosis-like growth and development. Kinetic studies revealed that epicotyls bent at their basal region or near cotyledonary node toward the direction far from the cotyledons with about 45 degrees in both seedlings grown on 1 g and under simulated microgravity conditions on the clinostat within 48 hrs after watering. Thereafter epicotyls grew keeping this orientation under simulated microgravity conditions on the clinostat, whereas those grown on 1 g changed the growth direction to vertical direction by negative gravitropic response. Automorphosis-like growth and development was induced by the application of auxin polar transport inhibitors (2,3,5-triiodobenzoic acid, N-(1-naphtyl)phthalamic acid, 9-hydroxyfluorene-9-carboxylic acid), but not an anti-auxin, p-chlorophenoxyisobutyric acid. Automorphosis-like epicotyl bending was also phenocopied by the application of inhibitors of stretch-activated channel, LaCl3 and GdCl3, and by the application of an inhibitor of protein kinase, cantharidin. These results suggest that automorphosis-like growth in epicotyls of etiolated pea seedlings is due to suppression of negative gravitropic responses on 1 g, and the growth and development of etiolated pea seedlings under 1 g conditions requires for normal activities of auxin polar transport and the gravisensing system relating to calcium channels. Possible mechanisms of perception and transduction of gravity signals to induce automorphosis are discussed.
The Decoration Operator: A Foundation for On-Line Dimensional Data Integration
DEFF Research Database (Denmark)
Pedersen, Dennis; Pedersen, Torben Bach; Riis, Karsten
2004-01-01
The changing data requirements of today's dynamic business environments are not handled well by current On-Line Analytical Processing (OLAP) systems. Physically integrating unexpected, external data into OLAP cubes, i.e., the data warehousing approach, is a long and time-consuming process, making...... logical, on-the-fly, integration the better choice in many situations. However, OLAP systems have no operations for integrating existing multidimensional cube data with external data. In this paper we present a novel multidimensional algebra operator, the decoration operator, which allows external data...... to be integrated in OLAP cubes as new dimensions, i.e., the cube is ``decorated'' with new dimensions which can subsequently be used just as the regular dimensions. We formally specify the semantics of the decoration operator, ensuring that semantic problems do not occur in the data integration process. We also...
Inter-operator Variability in Defining Uterine Position Using Three-dimensional Ultrasound Imaging
DEFF Research Database (Denmark)
Baker, Mariwan; Jensen, Jørgen Arendt; Behrens, Claus F.
2013-01-01
significantly larger inter-fractional uterine positional displacement, in some cases up to 20 mm, which outweighs the magnitude of current inter-operator variations. Thus, the current US-phantom-study suggests that the inter-operator variability in addressing uterine position is clinically irrelevant.......In radiotherapy the treatment outcome of gynecological (GYN) cancer patients is crucially related to reproducibility of the actual uterine position. The purpose of this study is to evaluate the inter-operator variability in addressing uterine position using a novel 3-D ultrasound (US) system....... The study is initiated by US-scanning of a uterine phantom (CIRS 404, Universal Medical, Norwood, USA) by seven experienced US operators. The phantom represents a female pelvic region, containing a uterus, bladder and rectal landmarks readily definable in the acquired US-scans. The organs are subjected...
Energy Technology Data Exchange (ETDEWEB)
Yeom, Choong Sub; Kim, Hyun Dae; Park, Kyung Seok; Park, Jong Woon [Institute for Advanced Engineering, Taejon (Korea, Republic of)
1995-07-01
This paper describes the results of simulation of a CANDU operational transient problem (re-startup after short shutdown) using the Coupled Reactor Kinetics(CRKIN) code developed previously with CANDU Reactor Regulating System (RRS) logic. The performance in the simulation is focused on investigating the behaviours of neutron power and regulating devices in accordance with the changes of xenon concentration following the operation of the RRS.
Energy Technology Data Exchange (ETDEWEB)
Penedo, M., E-mail: mapenedo@imm.cnm.csic.es; Hormeño, S.; Fernández-Martínez, I.; Luna, M.; Briones, F. [IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid (Spain); Raman, A. [Birck Nanotechnology Center and School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47904 (United States)
2014-10-27
Recent developments in dynamic Atomic Force Microscopy where several eigenmodes are simultaneously excited in liquid media are proving to be an excellent tool in biological studies. Despite its relevance, the search for a reliable, efficient, and strong cantilever excitation method is still in progress. Herein, we present a theoretical modeling and experimental results of different actuation methods compatible with the operation of Atomic Force Microscopy in liquid environments: ideal acoustic, homogeneously distributed force, distributed applied torque (MAC Mode™), photothermal and magnetostrictive excitation. From the analysis of the results, it can be concluded that magnetostriction is the strongest and most efficient technique for higher eigenmode excitation when using soft cantilevers in liquid media.
First operation of a powerful FEL with two-dimensional distributed feedback
Agarin, N V; Bobylev, V B; Ginzburg, N S; Ivanenko, V G; Kalinin, P V; Kuznetsov, S A; Peskov, N Yu; Sergeev, A S; Sinitsky, S L; Stepanov, V D
2000-01-01
A W-band (75 GHz) FEL of planar geometry driven by a sheet electron beam was realised using the pulse accelerator ELMI (0.8 MeV/3 kA/5 mu s). To provide the spatial coherence of radiation from different parts of the electron beam with a cross-section of 0.4x12 cm two-dimensional distributed feedback systems have been employed using a 2-D Bragg resonator of planar geometry. The resonator consisted of two 2-D Bragg reflectors separated by a regular waveguide section. The total energy in the microwave pulse of microsecond duration was 100 J corresponding to a power of approx 100 MW. The main component of the FEL radiation spectrum was at 75 GHz that corresponded to the zone of effective Bragg reflection found from 'cold' microwave testing of the resonator. The experimental data compared well with the results of theoretical analysis.
Kiryakova, Virginia S.
2012-11-01
The Laplace Transform (LT) serves as a basis of the Operational Calculus (OC), widely explored by engineers and applied scientists in solving mathematical models for their practical needs. This transform is closely related to the exponential and trigonometric functions (exp, cos, sin) and to the classical differentiation and integration operators, reducing them to simple algebraic operations. Thus, the classical LT and the OC give useful tool to handle differential equations and systems with constant coefficients. Several generalizations of the LT have been introduced to allow solving, in a similar way, of differential equations with variable coefficients and of higher integer orders, as well as of fractional (arbitrary non-integer) orders. Note that fractional order mathematical models are recently widely used to describe better various systems and phenomena of the real world. This paper surveys briefly some of our results on classes of such integral transforms, that can be obtained from the LT by means of "transmutations" which are operators of the generalized fractional calculus (GFC). On the list of these Laplace-type integral transforms, we consider the Borel-Dzrbashjan, Meijer, Krätzel, Obrechkoff, generalized Obrechkoff (multi-index Borel-Dzrbashjan) transforms, etc. All of them are G- and H-integral transforms of convolutional type, having as kernels Meijer's G- or Fox's H-functions. Besides, some special functions (also being G- and H-functions), among them - the generalized Bessel-type and Mittag-Leffler (M-L) type functions, are generating Gel'fond-Leontiev (G-L) operators of generalized differentiation and integration, which happen to be also operators of GFC. Our integral transforms have operational properties analogous to those of the LT - they do algebrize the G-L generalized integrations and differentiations, and thus can serve for solving wide classes of differential equations with variable coefficients of arbitrary, including non-integer order
Gamow-Jordan vectors and non-reducible density operators from higher-order S-matrix poles
International Nuclear Information System (INIS)
Bohm, A.; Loewe, M.; Maxson, S.; Patuleanu, P.; Puentmann, C.; Gadella, M.
1997-01-01
In analogy to Gamow vectors that are obtained from first-order resonance poles of the S-matrix, one can also define higher-order Gamow vectors which are derived from higher-order poles of the S-matrix. An S-matrix pole of r-th order at z R =E R -iΓ/2 leads to r generalized eigenvectors of order k=0,1,hor-ellipsis,r-1, which are also Jordan vectors of degree (k+1) with generalized eigenvalue (E R -iΓ/2). The Gamow-Jordan vectors are elements of a generalized complex eigenvector expansion, whose form suggests the definition of a state operator (density matrix) for the microphysical decaying state of this higher-order pole. This microphysical state is a mixture of non-reducible components. In spite of the fact that the k-th order Gamow-Jordan vectors has the polynomial time-dependence which one always associates with higher-order poles, the microphysical state obeys a purely exponential decay law. copyright 1997 American Institute of Physics
Study of three-dimensional PET and MR image registration based on higher-order mutual information
International Nuclear Information System (INIS)
Ren Haiping; Chen Shengzu; Wu Wenkai; Yang Hu
2002-01-01
Mutual information has currently been one of the most intensively researched measures. It has been proven to be accurate and effective registration measure. Despite the general promising results, mutual information sometimes might lead to misregistration because of neglecting spatial information and treating intensity variations with undue sensitivity. An extension of mutual information framework was proposed in which higher-order spatial information regarding image structures was incorporated into the registration processing of PET and MR. The second-order estimate of mutual information algorithm was applied to the registration of seven patients. Evaluation from Vanderbilt University and authors' visual inspection showed that sub-voxel accuracy and robust results were achieved in all cases with second-order mutual information as the similarity measure and with Powell's multidimensional direction set method as optimization strategy
Ryttov, Thomas A
2007-01-01
We present the conformal windows of SU(N) supersymmetric and nonsupersymmetric gauge theories with vector-like matter transforming according to higher irreducible representations of the gauge group. We determine the fraction of asymptotically free theories expected to develop an infrared fixed point and find that it does not depend on the specific choice of the representation. This result is exact in supersymmetric theories while it is an approximate one in the nonsupersymmetric case. The analysis allows us to size the unparticle world related to the existence of underlying gauge theories developing an infrared stable fixed point. We find that exactly 50 % of the asymptotically free theories can develop an infrared fixed point while for the nonsupersymmetric theories it is circa 25 %. When considering multiple representations, only for the nonsupersymmetric case, the conformal regions quickly dominate over the nonconformal ones. For four representations, 70 % of the asymptotically free space is filled by the ...
Energy Technology Data Exchange (ETDEWEB)
Hirotani, Kouichi [Academia Sinica, Institute of Astronomy and Astrophysics (ASIAA), P.O. Box 23-141, Taipei, Taiwan (China)
2015-01-10
We investigate the particle accelerator that arises in a rotating neutron-star magnetosphere. Simultaneously solving the Poisson equation for the electro-static potential, the Boltzmann equations for relativistic electrons and positrons, and the radiative transfer equation, we demonstrate that the electric field is substantially screened along the magnetic field lines by pairs that are created and separated within the accelerator. As a result, the magnetic-field-aligned electric field is localized in higher altitudes near the light cylinder and efficiently accelerates the positrons created in the lower altitudes outward but does not accelerate the electrons inward. The resulting photon flux becomes predominantly outward, leading to typical double-peak light curves, which are commonly observed from many high-energy pulsars.
Isomorphism of critical and off-critical operator spaces in two-dimensional quantum field theory
Energy Technology Data Exchange (ETDEWEB)
Delfino, G. [International School of Advanced Studies (SISSA), Trieste (Italy)]|[INFN sezione di Trieste (Italy); Niccoli, G. [Univ. de Cergy-Pontoise (France). LPTM
2007-12-15
For the simplest quantum field theory originating from a non-trivial fixed point of the renormalization group, the Lee-Yang model, we show that the operator space determined by the particle dynamics in the massive phase and that prescribed by conformal symmetry at criticality coincide. (orig.)
Directory of Open Access Journals (Sweden)
Kai Tsuruta
2013-05-01
Full Text Available We prove the existence of the wave operator for the Klein-Gordon-Schrodinger system with Yukawa coupling. This non-linearity type is below Strichartz scaling, and therefore classic perturbation methods will fail in any Strichartz space. Instead, we follow the "first iteration method" to handle these critical non-linearities.
Directory of Open Access Journals (Sweden)
Fukushima Kensuke
2017-01-01
Full Text Available Introduction: Periacetabular osteotomy (PAO is an effective joint-preserving procedure for young adults with developmental dysplasia of the hip. Although PAO provides excellent radiographic and clinical results, it is a technically demanding procedure with a distinct learning curve that requires careful 3D planning and, above all, has a number of potential complications. We therefore developed a pre-operative simulation method for PAO via creation of a new full-scale model. Methods: The model was prepared from the patient’s Digital Imaging and Communications in Medicine (DICOM formatted data from computed tomography (CT, for construction and assembly using 3D printing technology. A major feature of our model is that it is constructed from salt. In contrast to conventional models, our model provides a more accurate representation, at a lower manufacturing cost, and requires a shorter production time. Furthermore, our model realized simulated operation normally with using a chisel and drill without easy breakage or fissure. We were able to easily simulate the line of osteotomy and confirm acetabular version and coverage after moving to the osteotomized fragment. Additionally, this model allowed a dynamic assessment that avoided anterior impingement following the osteotomy. Results: Our models clearly reflected the anatomical shape of the patient’s hip. Our models allowed for surgical simulation, making realistic use of the chisel and drill. Our method of pre-operative simulation for PAO allowed for the assessment of accurate osteotomy line, determination of the position of the osteotomized fragment, and prevented anterior impingement after the operation. Conclusion: Our method of pre-operative simulation might improve the safety, accuracy, and results of PAO.
Zhao, Nian; Yang, Jin; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping
2016-01-01
This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life.
International Nuclear Information System (INIS)
Zhao, Nian; Yang, Jin; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping
2016-01-01
This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life
Zhao, Nian; Yang, Jin; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping
2016-01-01
This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life.
Energy Technology Data Exchange (ETDEWEB)
Zhao, Nian; Yang, Jin, E-mail: yangjin@cqu.edu.cn; Yu, Qiangmo; Zhao, Jiangxin; Liu, Jun; Wen, Yumei; Li, Ping [Department of Optoelectronic Engineering, Chongqing University, Chongqing 400044 (China)
2016-01-15
This work has demonstrated a novel piezoelectric energy harvester without a complex structure and appended component that is capable of scavenging vibration energy from arbitrary directions with multiple resonant frequencies. In this harvester, a spiral-shaped elastic thin beam instead of a traditional thin cantilever beam was adopted to absorb external vibration with arbitrary direction in three-dimensional (3D) spaces owing to its ability to bend flexibly and stretch along arbitrary direction. Furthermore, multiple modes in the elastic thin beam contribute to a possibility to widen the working bandwidth with multiple resonant frequencies. The experimental results show that the harvester was capable of scavenging the vibration energy in 3D arbitrary directions; they also exhibited triple power peaks at about 16 Hz, 21 Hz, and 28 Hz with the powers of 330 μW, 313 μW, and 6 μW, respectively. In addition, human walking and water wave energies were successfully converted into electricity, proving that our harvester was practical to scavenge the time-variant or multi-directional vibration energies in our daily life.
One-dimensional Schroedinger operators with interactions singular on a discrete set
International Nuclear Information System (INIS)
Gesztesy, F.; Kirsch, W.
We study the self-adjointness of Schroedinger operators -d 2 /dx 2 +V(x) on an arbitrary interval, (a,b) with V(x) locally integrable on (a,b)inverse slantX where X is a discrete set. The treatment of quantum mechanical systems describing point interactions or periodic (possibly strongly singular) potentials is thereby included and explicit examples are presented. (orig.)
Directory of Open Access Journals (Sweden)
Hasanova L. H.
2017-12-01
Full Text Available Nowadays permanent magnet synchronous machines those frequency-controlled from stator side with frequency inverters made on the basis of power transistors or fully controlled thyristors, are widely used as motors and generators. In future they are also promising a good application in transport, including marine. Modern frequency inverters are equipped with a control system based on sine-shaped pulse width modulation. While shaping the voltage in the output of the inverter, in addition to the fundamental harmonic, higher harmonic components are also included in the voltage shape, which certainly affect the operating parameters of the generator (electromagnetic torque, power, currents. To determine this effect the modeling and investigation technique of higher harmonic voltages in the "electric network – frequency converter – synchronous machine with permanent magnets" system has been developed. The proposed equations of a frequency-controlled permanent magnet synchronous machine allow relatively simply reproduce the harmonic composition of the voltage in the output of a frequency inverter equipped with the control system based on a sinusoidal pulse width modulation. The developed research technique can be used for inverters with any number and composition of voltage harmonic components feeding a stator winding of a permanent magnet synchronous machine. On a particular case, the efficiency of the research technique of the higher harmonics influence on the operating parameters of the generator has been demonstrated. At the same time, the study has been carried out taking into account the shape of the voltage curve feeding the windings of the synchronous machine containing in addition to the fundamental harmonic the 8, 10, 11, 13, 14 and 16-th harmonic components, and the rated active power of the synchronous machine has been equal to 1 500 kW.
Fu, Jun; Guo, Zheng; Wang, Zhen; Li, Xiangdong; Fan, Hongbin; Li, Jing; Pei, Yanjun; Pei, Guoxian; Li, Dan
2014-03-01
To explore the effectiveness of excision and reconstruction of bone tumor by using operation guide plate made by variety of three-dimensional (3-D) printing techniques, and to compare the advantages and disadvantages of different 3-D printing techniques in the manufacture and application of operation guide plate. Between September 2012 and January 2014, 31 patients with bone tumor underwent excision and reconstruction of bone tumor by using operation guide plate. There were 19 males and 12 females, aged 6-67 years (median, 23 years). The disease duration ranged from 15 days to 12 months (median, 2 months). There were 13 cases of malignant tumor and 18 cases of benign tumor. The tumor located in the femur (9 cases), the spine (7 cases), the tibia (6 cases), the pelvis (5 cases), the humerus (3 cases), and the fibula (1 case). Four kinds of 3-D printing technique were used in processing operation guide plate: fused deposition modeling (FDM) in 9 cases, stereo lithography appearance (SLA) in 14 cases, 3-D printing technique in 5 cases, and selective laser sintering (SLS) in 3 cases; the materials included ABS resin, photosensitive resin, plaster, and aluminum alloy, respectively. Before operation, all patients underwent thin layer CT scanning (0.625 mm) in addition to conventional imaging. The data were collected for tumor resection design, and operation guide plate was designed on the basis of excision plan. Preoperatively, the operation guide plates were made by 3-D printing equipment. After sterilization, the guide plates were used for excision and reconstruction of bone tumor. The time of plates processing cycle was recorded to analyse the efficiency of 4 kinds of 3-D printing techniques. The time for design and operation and intraoperative fluoroscopy frequency were recorded. Twenty-eight patients underwent similar operations during the same period as the control group. The processing time of operation guide plate was (19.3 +/- 6.5) hours in FDM, (5.2 +/- 1
Pre-operative evaluation of cleft palate using three dimensional computerized tomography (s-D CT)
International Nuclear Information System (INIS)
Azia, A.; Hashmi, R.
1999-01-01
Cleft palate is a congenital anomaly with major development concerns. Surgery with bone grafting is often required to correct the lesion. With the introduction of 3-D CT the evaluation of cleft pa late has become more accurate. We present two cases of cleft palate, which were operated upon with bone grafting. We employed 3-D CT techniques in addition to the conventional 2-D CT, 3-D CT improves the estimation of the required bone graft and signification reduces length of surgery and complications. (author)
Universal bounds on spectral measures of one-dimensional Schrödinger operators
Remling, C
2002-01-01
Consider a Schrödinger operator $H=-d^2/dx^2+V(x)$ on $L_2(0,\\infty)$ and suppose that an initial piece of the potential $V(x)$, $0
Operator coproduct-realization of quantum group transformations in two dimensional gravity, 1
Cremmer, E; Schnittger, J; Cremmer, E; Gervais, J L; Schnittger, J
1996-01-01
A simple connection between the universal R matrix of U_q(sl(2)) (for spins \\demi and J) and the required form of the co-product action of the Hilbert space generators of the quantum group symmetry is put forward. This gives an explicit operator realization of the co-product action on the covariant operators. It allows us to derive the quantum group covariance of the fusion and braiding matrices, although it is of a new type: the generators depend upon worldsheet variables, and obey a new central extension of U_q(sl(2)) realized by (what we call) fixed point commutation relations. This is explained by showing that the link between the algebra of field transformations and that of the co-product generators is much weaker than previously thought. The central charges of our extended U_q(sl(2)) algebra, which includes the Liouville zero-mode momentum in a nontrivial way are related to Virasoro-descendants of unity. We also show how our approach can be used to derive the Hopf algebra structure of the extended quant...
Okonogi, Shinichi; Kondo, Kosuke; Harada, Naoyuki; Masuda, Hiroyuki; Nemoto, Masaaki; Sugo, Nobuo
2017-09-01
As the anatomical three-dimensional (3D) positional relationship around the anterior clinoid process (ACP) is complex, experience of many surgeries is necessary to understand anterior clinoidectomy (AC). We prepared a 3D synthetic image from computed tomographic angiography (CTA) and magnetic resonance imaging (MRI) data and a rapid prototyping (RP) model from the imaging data using a 3D printer. The objective of this study was to evaluate anatomical reproduction of the 3D synthetic image and intraosseous region after AC in the RP model. In addition, the usefulness of the RP model for operative simulation was investigated. The subjects were 51 patients who were examined by CTA and MRI before surgery. The size of the ACP, thickness and length of the optic nerve and artery, and intraosseous length after AC were measured in the 3D synthetic image and RP model, and reproducibility in the RP model was evaluated. In addition, 10 neurosurgeons performed AC in the completed RP models to investigate their usefulness for operative simulation. The RP model reproduced the region in the vicinity of the ACP in the 3D synthetic image, including the intraosseous region, at a high accuracy. In addition, drilling of the RP model was a useful operative simulation method of AC. The RP model of the vicinity of ACP, prepared using a 3D printer, showed favorable anatomical reproducibility, including reproduction of the intraosseous region. In addition, it was concluded that this RP model is useful as a surgical education tool for drilling.
Directory of Open Access Journals (Sweden)
Zhou Yang
2017-01-01
Full Text Available High pressures, high speeds, low noise and miniaturization is the direction of development in hydraulic pump. According to the development trend, an operating helical rotor pump (HRP at high speeds and high pressures has been designed and produced, which rotational speed can reach 12000r/min and outlet pressure is as high as 25MPa. Three-dimensional simulation with and without cavitation inside the HRP is completed by the means of the computational fluid dynamics (CFD in this paper, which contributes to understand the complex fluid flow inside it. Moreover, the influences of the rotational speeds of the HRP with and without cavitation has been simulated at 25MPa.
Hanke, Jan-Philipp; Freimuth, Frank; Blügel, Stefan; Mokrousov, Yuriy
2018-04-01
We present an advanced first-principles formalism to evaluate the Dzyaloshinskii-Moriya interaction (DMI) in its modern theory as well as Berry curvatures in complex spaces based on a higher-dimensional Wannier interpolation. Our method is applied to the Co-based trilayer systems IrδPt1-δ/Co/Pt and AuγPt1-γ/Co/Pt, where we gain insights into the correlations between the electronic structure and the DMI, and we uncover prominent sign changes of the chiral interaction with the overlayer composition. Beyond the discussed phenomena, the scope of applications of our Wannier-based scheme is particularly broad as it is ideally suited to study efficiently the Hamiltonian evolution under the slow variation of very general parameters.
Cândido, Duarte N C; de Oliveira, Jean Gonçalves; Borba, Luis A B
2018-05-08
Paragangliomas are tumors originating from the paraganglionic system (autonomic nervous system), mostly found at the region around the jugular bulb, for which reason they are also termed glomus jugulare tumors (GJT). Although these lesions appear to be histologically benign, clinically they present with great morbidity, especially due to invasion of nearby structures such as the lower cranial nerves. These are challenging tumors, as they need complex approaches and great knowledge of the skull base. We present the case of a 31-year-old woman, operated by the senior author, with a 1-year history of tinnitus, vertigo, and progressive hearing loss, that evolved with facial nerve palsy (House-Brackmann IV) 2 months before surgery. Magnetic resonance imaging and computed tomography scans demonstrated a typical lesion with intense flow voids at the jugular foramen region with invasion of the petrous and tympanic bone, carotid canal, and middle ear, and extending to the infratemporal fossa (type C2 of Fisch's classification for GJT). During the procedure the mastoid part of the facial nerve was identified involved by tumor and needed to be resected. We also describe the technique for nerve reconstruction, using an interposition graft from the great auricular nerve, harvested at the beginning of the surgery. We achieved total tumor resection with a remarkable postoperative course. The patient also presented with facial function after 6 months. The patient consented with publication of her images.
International Nuclear Information System (INIS)
Luevano, Jose-Ruben
2011-01-01
Analytical expressions for the invariant densities for a class of discrete two dimensional chaotic systems are given. The method of separation of variables for the associated Frobenius-Perron equation is introduced. These systems are related to nonlinear difference equations which are of the type x k+2 = T(x k ). The function T is a chaotic map of an interval whose chaotic behaviour is inherited to the two dimensional one. We work out in detail some examples, with T an expansive or intermittent map, in order to expose the method. Finally, we discuss how to generalize the method to higher dimensional maps.
International Nuclear Information System (INIS)
Charleston, B.D.; Beckman, F.H.; Franco, M.J.; Charleston, D.B.
1981-01-01
A versatile electronic-analogue image processing system has been developed for use in improving the quality of various types of images with emphasis on those encountered in experimental and diagnostic medicine. The operational principle utilizes spatial filtering which selectively controls the contrast of an image according to the spatial frequency content of relevant and non-relevant features of the image. Noise can be reduced or eliminated by selectively lowering the contrast of information in the high spatial frequency range. Edge sharpness can be enhanced by accentuating the upper midrange spatial frequencies. Both methods of spatial frequency control may be adjusted continuously in the same image to obtain maximum visibility of the features of interest. A precision video camera is used to view medical diagnostic images, either prints, transparencies or CRT displays. The output of the camera provides the analogue input signal for both the electronic processing system and the video display of the unprocessed image. The video signal input to the electronic processing system is processed by a two-dimensional spatial convolution operation. The system employs charged-coupled devices (CCDs), both tapped analogue delay lines (TADs) and serial analogue delay lines (SADs), to store information in the form of analogue potentials which are constantly being updated as new sampled analogue data arrive at the input. This information is convolved with a programmed bipolar radially symmetrical hexagonal function which may be controlled and varied at each radius by the operator in real-time by adjusting a set of front panel controls or by a programmed microprocessor control. Two TV monitors are used, one for processed image display and the other for constant reference to the original image. The working prototype has a full-screen display matrix size of 200 picture elements per horizontal line by 240 lines. The matrix can be expanded vertically and horizontally for the
Zhao, Jingxin; Ma, Yachang; Han, Dong; Jin, Yu
2017-10-01
To investigate the application value of three-dimensional (3-D) printing technology in the operation of distal tibia fracture involving epiphyseal plate injury for teenagers. The retrospective analysis was conducted on the clinical data of 16 cases of children patients with distal tibia fracture involving epiphyseal plate injury undergoing the operation by using of 3-D printing technology between January 2014 and December 2015. There were 12 males and 4 females with an age of 9-14 years (mean, 12.8 years). The causes of injury included traffic accident injury in 9 cases, heavy pound injury in 3 cases, and sport injury in 4 cases. The time from injury to operation was 3-92 hours (mean, 25.8 hours). According to Salter-Harris typing standard, the typing for epiphyseal injury was classified as type Ⅱ in 11 cases, type Ⅲ in 4 cases, and type Ⅳ in 1 case. The thin slice CT scan on the affected limb was performed before operation, and the Mimics14.0 medical software was applied for the design and the 1∶1 fracture model was printed by the 3-D printer; the stimulation of operative reduction was made in the fracture model, and bone plate, Kirschner wire, and hollow screw with the appropriate size were chosen, then the complete operative approach and method were designed and the internal fixator regimen was chosen, then the practical operation was performed based on the preoperative design regimen. The operation time was 40-68 minutes (mean, 59.1 minutes); the intraoperative blood loss was 5-102 mL (mean, 35 mL); the intraoperative fluoroscopy times was 2-6 times (mean, 2.8 times). All the patiens were followed up 12-24 months (mean, 15 months). The fracture of 15 cases reached anatomic reduction, and 1 cases had no anatomic reduction with the displaced end less than 1 mm. All the fractures reached bony union with the healing time of 2-4 months (mean, 2.6 months). There was no deep vein thrombosis, premature epiphyseal closure and oblique, or uneven ankle surface
International Nuclear Information System (INIS)
Kaneko, O.
2012-11-01
The Large Helical Device (LHD) has shown the advantages of heliotron plasma for fusion reactor from operational point of view not only such as disruption free and steady state operation, but also as high density and stable high beta operation. Since the last Fusion Energy Conference in Daejon in 2010 (Yamada, 2011 Nucl. Fusion 51 094021), physical understanding as well as parameter improvement of net-current free helical plasmas has progressed successively. The current efforts are focused on optimization of plasma edge condition to extend the operation regime towards higher ion temperature and more stable high density. In LHD a part of open helical divertors are being modified to the baffle-structured closed ones to aim at active control of the edge plasma. It has been demonstrated that the neutral pressure in the closed helical divertor was more than 10 times higher than that in the open helical divertor. The central ion temperature has exceeded 7 keV. This high-T i plasma was obtained by a carbon pellet injection and the kinetic-energy confinement was improved by a factor of 1.5. Transport analysis of the high-T i plasmas has shown that the ion-thermal conductivity and the viscosity reduced after the pellet injection. Study of physics in 3-D geometry is highlighted in the topics of the response to Resonant Magnetic Perturbation such as ELM mitigation and divertor detachment. Novel approaches of non-local and non-diffusive transport have also been advanced. In this paper, highlighted results in these two years are overviewed. (author)
Directory of Open Access Journals (Sweden)
Pierre-Jean eArduin
2014-07-01
Full Text Available The design of efficient neuroprosthetic devices has become a major challenge for the long-term goal of restoring autonomy to motor-impaired patients. One approach for brain control of actuators consists in decoding the activity pattern obtained by simultaneously recording large neuronal ensembles in order to predict in real-time the subject’s intention, and move the prosthesis accordingly. An alternative way is to assign the output of one or a few neurons by operant conditioning to control the prosthesis with rules defined by the experimenter, and rely on the functional adaptation of these neurons during learning to reach the desired behavioral outcome. Here, several motor cortex neurons were recorded simultaneously in head-fixed awake rats and were conditioned, one at a time, to modulate their firing rate up and down in order to control the speed and direction of a one-dimensional actuator carrying a water bottle. The goal was to maintain the bottle in front of the rat’s mouth, allowing it to drink. After learning, all conditioned neurons modulated their firing rate, effectively controlling the bottle position so that the drinking time was increased relative to chance. The mean firing rate averaged over all bottle trajectories depended non-linearly on position, so that the mouth position operated as an attractor. Some modifications of mean firing rate were observed in the surrounding neurons, but to a lesser extent. Notably, the conditioned neuron reacted faster and led to a better control than surrounding neurons, as calculated by using the activity of those neurons to generate simulated bottle trajectories. Our study demonstrates the feasibility, even in the rodent, of using a motor cortex neuron to control a prosthesis in real-time bidirectionally. The learning process includes modifications of the activity of neighboring cortical neurons, while the conditioned neuron selectively leads the activity patterns associated with the prosthesis
International Nuclear Information System (INIS)
Lemke, R.W.; Genoni, T.C.; Spencer, T.A.
1999-01-01
This work is an attempt to elucidate effects that may limit efficiency in magnetrons operated at relativistic voltages (V ∼ 500 kV). Three-dimensional particle-in-cell simulation is used to investigate the behavior of 14 and 22 cavity, cylindrical, rising-sun magnetrons. Power is extracted radially through a single iris located at the end of every other cavity. Numerical results show that in general output power and efficiency increase approximately linearly with increasing iris width (decreasing vacuum Q) until the total Q becomes too low for stable oscillation in the n-mode to be maintained. Beyond this point mode competition and/or switching occur and efficiency decreases. Results reveal that the minimum value of Q (maximum efficiency) that can be achieved prior to the onset of mode competition is significantly affected by the magnitude of the 0-space-harmonic of the π-mode, a unique characteristic of rising-suns, and by the magnitude of the electron current density (space-charge effects). By minimizing these effects, up to 3.7 GW output power has been produced at an efficiency of 40%
Lam, D L; Mitsumori, L M; Neligan, P C; Warren, B H; Shuman, W P; Dubinsky, T J
2012-12-01
Autologous breast reconstructive surgery with deep inferior epigastric artery (DIEA) perforator flaps has become the mainstay for breast reconstructive surgery. CT angiography and three-dimensional image post processing can depict the number, size, course and location of the DIEA perforating arteries for the pre-operative selection of the best artery to use for the tissue flap. Knowledge of the location and selection of the optimal perforating artery shortens operative times and decreases patient morbidity.
International Nuclear Information System (INIS)
Maksudov, F.G.; Gusejnov, G.Sh.
1986-01-01
Inverse scattering problem for the quadratic bundle of the Schroedinger one-dimensional operators in the whole axis is solved. The problem solution is given on the assumption of the discrete spectrum absence. In the discrete spectrum presence the inverse scattering problem solution is known for the Shroedinger differential equation considered
International Nuclear Information System (INIS)
Yanagisawa, Kazuaki; Ishiguro, Misako; Yamazaki, Takashi; Tokunaga, Yasuo.
1985-02-01
Though the two-dimensional fuel behaviour analysis code FEMAXI-III has been developed by JAERI in form of optimized scalar computer code, the call for more efficient code usage generally arized from the recent trends like high burn-up and load follow operation asks the code into further modification stage. A principal aim of the modification is to transform the already implemented scalar type subroutines into vectorized forms to make the programme structure efficiently run on high-speed vector computers. The effort of such structural modification has been finished on a fair way to success. The benchmarking two tests subsequently performed to examine the effect of the modification led us the following concluding remarks: (1) In the first benchmark test, comparatively high-burned three fuel rods that have been irradiated in HBWR, BWR, and PWR condition are prepared. With respect to all cases, a net computing time consumed in the vectorized FEMAXI is approximately 50 % less than that consumed in the original one. (2) In the second benchmark test, a total of 26 PWR fuel rods that have been irradiated in the burn-up ranges of 13-30 MWd/kgU and subsequently power ramped in R2 reactor, Sweden is prepared. In this case the code is purposed to be used for making an envelop of PCI-failure threshold through 26 times code runs. Before coming to the same conclusion, the vectorized FEMAXI-III consumed a net computing time 18 min., while the original FEMAXI-III consumed a computing time 36 min. respectively. (3) The effects obtained from such structural modification are found to be significantly attributed to saving a net computing time in a mechanical calculation in the vectorized FEMAXI-III code. (author)
Liesen, Joseph J.
2017-01-01
The higher education industry uses the very latest technologies to effectively prepare students for their careers, but these technologies often contain vulnerabilities that can be exploited via their connection to the Internet. The complex task of securing information and computing systems is made more difficult at institutions of higher education…
DEFF Research Database (Denmark)
Reigosa, Paula Diaz; Iannuzzo, Francesco; Munk-Nielsen, Stig
2016-01-01
the Finite-Element-Method AnSYS Q3D Extractor, electromagnetic simulations are conducted to extract the self and mutual inductance from the six different layouts. PSpice simulations are used to reveal that the stray parameters inside the module play an important role under normal and abnormal operations...
On butterfly effect in higher derivative gravities
Energy Technology Data Exchange (ETDEWEB)
Alishahiha, Mohsen [School of Physics, Institute for Research in Fundamental Sciences (IPM),P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Davody, Ali; Naseh, Ali; Taghavi, Seyed Farid [School of Particles and Accelerators, Institute for Research in Fundamental Sciences (IPM),P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of)
2016-11-07
We study butterfly effect in D-dimensional gravitational theories containing terms quadratic in Ricci scalar and Ricci tensor. One observes that due to higher order derivatives in the corresponding equations of motion there are two butterfly velocities. The velocities are determined by the dimension of operators whose sources are provided by the metric. The three dimensional TMG model is also studied where we get two butterfly velocities at generic point of the moduli space of parameters. At critical point two velocities coincide.
On butterfly effect in higher derivative gravities
International Nuclear Information System (INIS)
Alishahiha, Mohsen; Davody, Ali; Naseh, Ali; Taghavi, Seyed Farid
2016-01-01
We study butterfly effect in D-dimensional gravitational theories containing terms quadratic in Ricci scalar and Ricci tensor. One observes that due to higher order derivatives in the corresponding equations of motion there are two butterfly velocities. The velocities are determined by the dimension of operators whose sources are provided by the metric. The three dimensional TMG model is also studied where we get two butterfly velocities at generic point of the moduli space of parameters. At critical point two velocities coincide.
Institute of Scientific and Technical Information of China (English)
Hua WANG; ALATANCANG; Junjie HUANG
2011-01-01
The authors investigate the completeness of the system of eigen or root vectors of the 2 x 2 upper triangular infinite-dimensional Hamiltonian operator H0.First,the geometrical multiplicity and the algebraic index of the eigenvalue of H0 are considered.Next,some necessary and sufficient conditions for the completeness of the system of eigen or root vectors of H0 are obtained. Finally,the obtained results are tested in several examples.
Bordogna, Claudia M.
2018-01-01
For too long, transnational higher education (TNE) has been linked to discourse predominately focused upon strategic implementation, quality assurance, and pedagogy. While these aspects are important when designing and managing overseas provisions, there is a lack of research focusing on the social interactions that influence the pace and…
Selvaratnam, Viswanathan
1988-01-01
Third World adoption of the Western university and the accompanying Eurocentric system of information flow is criticized as sometimes being counterproductive and alien to developing nations. The potential for a self-reliant, interdependent higher education system among Third World countries is discussed. (MSE)
Crozier, Fiona, Ed.; Costes, Nathalie, Ed.; Ranne, Paula, Ed.; Stalter, Maria, Ed.
2010-01-01
The history of ENQA (European Association for Quality Assurance in Higher Education) arises in the late 1990s when the first formal procedures for quality assurance begun to stabilize on a national level. As a result of the European Pilot Projects in the field of external quality assurance during the nineties, participants felt the need for…
Bridge, Freda; Fisher, Roy; Webb, Keith
2003-01-01
The Consortium for Post-Compulsory Education and Training (CPCET) is a single subject consortium of further education and higher education providers of professional development relating to in-service teacher training for the whole of the post-compulsory sector. Involving more than 30 partners spread across the North of England, CPCET evolved from…
Pawluczyk, J.; Sosna, A.; Wojnowski, D.; Koźniewski, A.; Romanis, M.; Gawron, W.; Piotrowski, J.
2017-10-01
We report on the quadrant photon HgCdTe detectors optimized for 2-11 μm wavelength spectral range and Peltier or no cooling, and photosensitive area of a quad-cell of 1×1 to 4×4 mm. The devices are fabricated as photoconductors or multiple photovoltaic cells connected in series (PVM). The former are characterized by a relatively uniform photosensitive area. The PVM photovoltaic cells are distributed along the wafer surface, comprising a periodical stripe structure with a period of 20 μm. Within each period, there is an insensitive gap/trench spot of size close to the period, but becomes negligible for the optimal spot size comparable to a quadrant-cell area. The photoconductors produce 1/f noise with about 10 kHz knee frequency, due to bias necessary for their operation. The PVM photodiodes are typically operated at 0 V bias, so they generate no 1/f noise and operation from DC is enabled. At 230 K, upper corner frequency of 16 to 100 MHz is obtained for photoconductor and 60 to 80 MHz for PVM, normalized detectivity D* 6×107 cm×Hz1/2/W to >1.4×108 cm×Hz1/2/W for photoconductor and >1.7×108 cm·Hz1/2/W for PVM, allowing for position control of the radiation beam with submicron accuracy at 16 MHz, 10.6 μm wavelength of pulsed radiation spot of 0.8 mm dia at the close-to-maximal input radiation power density in a range of detector linear operation.
Directory of Open Access Journals (Sweden)
Husni Ana,am Ali Salem
2017-12-01
Full Text Available The purpose of this study was to build a proposed educational model for improving knowledge-exchange processes between the Ministry of Education and Higher Education institutions in Jordan. The sample of the study consisted of (301 educational leaders: (158 academic staff members from the Faculty of Educational Sciences – University of Jordan – and the Faculty of Education in Yarmouk University; and (143 members from the center of Jordanian Ministry of Education for the academic year 2016/2017. To achieve the aims of the study, the researcher built a questionnaire, consisting of (88 items as tool for collecting data. The research tool was checked for its validity and reliability semantics. To analyze the data, means and standard deviation were used. The results of the study showed that the educational leaders rated the degree of practicing knowledge-exchange processes between Jordanian Ministry of Education and Higher Education institutions in Jordan as (moderate. Also, they rated the obstacles that face knowledge-exchange processes as (moderate. The study concluded with a proposed educational model for improving knowledge-exchange processes between the Ministry of Education and Higher Education institutions in Jordan, and recommended to be approved and applied in Jordan. Keywords: A Proposed educational model, Knowledge-exchange processes, Practicing degree, Obstacles, Jordanian Universities, Jordanian Ministry of Education
International Nuclear Information System (INIS)
Kevrekidis, P.G.; Herring, G.J.; Lafortune, S.; Hoq, Q.E.
2012-01-01
We propose a consideration of the properties of the two-dimensional Ablowitz–Ladik discretization of the ubiquitous nonlinear Schrödinger (NLS) model. We use singularity confinement techniques to suggest that the relevant discretization should not be integrable. More importantly, we identify the prototypical solitary waves of the model and examine their stability, illustrating the remarkable feature that near the continuum limit, this discretization leads to the absence of collapse and complete spectral wave stability, in stark contrast to the standard discretization of the NLS. We also briefly touch upon the three-dimensional case and generalizations of our considerations therein, and also present some more exotic solutions of the model, such as exact line solitons and discrete vortices. -- Highlights: ► The two-dimensional version of the Ablowitz–Ladik discretization of the nonlinear Schrödinger (NLS) equation is considered. ► It is found that near the continuum limit the fundamental discrete soliton is spectrally stable. ► This finding is in sharp contrast with the case of the standard discretization of the NLS equation. ► In the three-dimensional version of the model, the fundamental solitons are unstable. ► Additional waveforms such as exact unstable line solitons and discrete vortices are also touched upon.
Energy Technology Data Exchange (ETDEWEB)
Kevrekidis, P.G., E-mail: kevrekid@gmail.com [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003-4515 (United States); Herring, G.J. [Department of Mathematics and Statistics, Cameron University, Lawton, OK 73505 (United States); Lafortune, S. [Department of Mathematics, College of Charleston, Charleston, SC 29401 (United States); Hoq, Q.E. [Department of Mathematics and Computer Science, Western New England College, Springfield, MA 01119 (United States)
2012-02-06
We propose a consideration of the properties of the two-dimensional Ablowitz–Ladik discretization of the ubiquitous nonlinear Schrödinger (NLS) model. We use singularity confinement techniques to suggest that the relevant discretization should not be integrable. More importantly, we identify the prototypical solitary waves of the model and examine their stability, illustrating the remarkable feature that near the continuum limit, this discretization leads to the absence of collapse and complete spectral wave stability, in stark contrast to the standard discretization of the NLS. We also briefly touch upon the three-dimensional case and generalizations of our considerations therein, and also present some more exotic solutions of the model, such as exact line solitons and discrete vortices. -- Highlights: ► The two-dimensional version of the Ablowitz–Ladik discretization of the nonlinear Schrödinger (NLS) equation is considered. ► It is found that near the continuum limit the fundamental discrete soliton is spectrally stable. ► This finding is in sharp contrast with the case of the standard discretization of the NLS equation. ► In the three-dimensional version of the model, the fundamental solitons are unstable. ► Additional waveforms such as exact unstable line solitons and discrete vortices are also touched upon.
Kazantsev, A. E.; Skoptsov, M. B.; Stepanyantz, K. V.
2017-11-01
We consider the general 𝒩 = 1 supersymmetric gauge theory with matter, regularized by higher covariant derivatives without breaking the BRST invariance, in the massless limit. In the ξ-gauge we obtain the (unrenormalized) expression for the two-point Green function of the quantum gauge superfield in the one-loop approximation as a sum of integrals over the loop momentum. The result is presented as a sum of three parts: the first one corresponds to the pure supersymmetric Yang-Mills theory in the Feynman gauge, the second one contains all gauge-dependent terms, and the third one is the contribution of diagrams with a matter loop. For the Feynman gauge and a special choice of the higher derivative regulator in the gauge fixing term, we analytically calculate these integrals in the limit k → 0. In particular, in addition to the leading logarithmically divergent terms, which are determined by integrals of double total derivatives, we also find the finite constants.
Directory of Open Access Journals (Sweden)
Darius Zizys
2015-12-01
Full Text Available The piezoelectric transduction mechanism is a common vibration-to-electric energy harvesting approach. Piezoelectric energy harvesters are typically mounted on a vibrating host structure, whereby alternating voltage output is generated by a dynamic strain field. A design target in this case is to match the natural frequency of the harvester to the ambient excitation frequency for the device to operate in resonance mode, thus significantly increasing vibration amplitudes and, as a result, energy output. Other fundamental vibration modes have strain nodes, where the dynamic strain field changes sign in the direction of the cantilever length. The paper reports on a dimensionless numerical transient analysis of a cantilever of a constant cross-section and an optimally-shaped cantilever with the objective to accurately predict the position of a strain node. Total effective strain produced by both cantilevers segmented at the strain node is calculated via transient analysis and compared to the strain output produced by the cantilevers segmented at strain nodes obtained from modal analysis, demonstrating a 7% increase in energy output. Theoretical results were experimentally verified by using open-circuit voltage values measured for the cantilevers segmented at optimal and suboptimal segmentation lines.
Vilardy, Juan M.; Giacometto, F.; Torres, C. O.; Mattos, L.
2011-01-01
The two-dimensional Fast Fourier Transform (FFT 2D) is an essential tool in the two-dimensional discrete signals analysis and processing, which allows developing a large number of applications. This article shows the description and synthesis in VHDL code of the FFT 2D with fixed point binary representation using the programming tool Simulink HDL Coder of Matlab; showing a quick and easy way to handle overflow, underflow and the creation registers, adders and multipliers of complex data in VHDL and as well as the generation of test bench for verification of the codes generated in the ModelSim tool. The main objective of development of the hardware architecture of the FFT 2D focuses on the subsequent completion of the following operations applied to images: frequency filtering, convolution and correlation. The description and synthesis of the hardware architecture uses the XC3S1200E family Spartan 3E FPGA from Xilinx Manufacturer.
Directory of Open Access Journals (Sweden)
WANG Qing-shan
2017-06-01
Full Text Available In view of the difficulties on technology of rotor chute in high voltage induction motor，the desig method adopted stator chute structure is put forward． The mathematical model of three dimensional nonlinear transient field for solving stator chute in high voltage induction motor is set up． Through the three dimensional entity model of motor，three dimensional finite element method based on T，ψ － ψ electromagnetic potential is adopted for the analysis and calculation of stator chute in high voltage induction motor under rated condition． The distributions long axial of fundamental wave magnetic field and tooth harmonic wave magnetic field are analyzed after stator chute，and the weakening effects on main tooth harmonic magnetic field are researched． Further more，the comparison analysis of main performance parameters of chute and straight slot is carried out under rated condition． The results show that the electrical performance of stator chute is better than that of straight slot in high voltage induction motor，and the tooth harmonic has been sharply decreased
International Nuclear Information System (INIS)
Nanayakkara, Asiri
2005-01-01
The pseudo Hermiticity with respect to the exchange operators of N-D complex Hamiltonians is investigated. It is shown that if an N-D Hamiltonian is pseudo Hermitian and any eigenfunction of it retains π α T symmetry then the corresponding eigen value is real, where π α is an exchange operator with respect to the permutation α of coordinates and T is the time reversal operator. We construct a special class of N-D pseudo Hermitian Hamiltonians with respect to exchange operators from both N/2-D and N-D general complex Hamiltonians. Examples are presented for Hamiltonians with πT symmetry (π:x↔y, p x ↔p y ) and the reality of these systems are investigated.
Lin, Hsiu Hsia; Kim, Sun-Goo; Kim, Hye-Young; Niu, Lien-Shin; Lo, Lun-Jou
2017-03-01
The objective of this prospective, double-blind, randomized clinical trial was to compare the effect of 2 dexamethasone dosages on reducing facial swelling after orthognathic surgery through 3-dimensional (3D) photogrammetry. Patients were classified into group 1 (control group) and group 2 (study group), depending on the administered dexamethasone dosage (5 and 15 mg, respectively). Three-dimensional images were recorded at 5 time points: preoperative (T0) and postoperative at 48 ± 6 hours (T1), 1 week (T2), 1 month (T3), and 6 months (T4). A preliminary study was performed on 5 patients, in whom 3D images were captured at 24, 36, 48, and 60 hours postoperatively to record serial changes in facial swelling. Facial swelling at T1, T2, and T3 and the reduction in swelling at T2 and T3 compared with that at the baseline (T4) were calculated. Possible complications, namely, adrenal suppression, wound dehiscence, wound infection, and postoperative nausea and vomiting were evaluated. In total, 68 patients were enrolled, of whom 25 patients in group 1 and 31 patients in group 2 were eligible for final evaluation. No significant differences were found between the 2 groups at any period. On average, the swelling subsided by 86% at 1 month after the orthognathic surgery. Facial swelling peaked approximately 48 hours after the surgery. The incidence of nausea and vomiting did not differ significantly between the groups. The effect of 5 and 15 mg of dexamethasone on facial swelling reduction as well as on nausea and vomiting after orthognathic surgery was not significantly different.
International Nuclear Information System (INIS)
Chang, C.S.; Miller, R.L.
1983-01-01
It has long been recognized that if an EBT-confined plasma could be maintained in the collisionless-ion regime, characterized by positive ambipolar potential and positive radial electric field, the particle loss rates could be reduced by a large factor. The extent to which the loss rate of energy could be reduced has not been as clearly determined, and has been investigated recently using a one-dimensional, time-dependent transport code developed for this purpose. We find that the energy confinement can be improved by roughly an order of magnitude by maintaining a positive radial electric field that increases monotonically with radius, giving a large ExB drift near the outer edge of the core plasma. The radial profiles of heat deposition required to sustain these equilibria will be presented, and scenarios for obtaining dynamical access to the equilibria will be discussed
Nicholls, David P
2018-04-01
The faithful modelling of the propagation of linear waves in a layered, periodic structure is of paramount importance in many branches of the applied sciences. In this paper, we present a novel numerical algorithm for the simulation of such problems which is free of the artificial singularities present in related approaches. We advocate for a surface integral formulation which is phrased in terms of impedance-impedance operators that are immune to the Dirichlet eigenvalues which plague the Dirichlet-Neumann operators that appear in classical formulations. We demonstrate a high-order spectral algorithm to simulate these latter operators based upon a high-order perturbation of surfaces methodology which is rapid, robust and highly accurate. We demonstrate the validity and utility of our approach with a sequence of numerical simulations.
Nicholls, David P.
2018-04-01
The faithful modelling of the propagation of linear waves in a layered, periodic structure is of paramount importance in many branches of the applied sciences. In this paper, we present a novel numerical algorithm for the simulation of such problems which is free of the artificial singularities present in related approaches. We advocate for a surface integral formulation which is phrased in terms of impedance-impedance operators that are immune to the Dirichlet eigenvalues which plague the Dirichlet-Neumann operators that appear in classical formulations. We demonstrate a high-order spectral algorithm to simulate these latter operators based upon a high-order perturbation of surfaces methodology which is rapid, robust and highly accurate. We demonstrate the validity and utility of our approach with a sequence of numerical simulations.
-Dimensional Fractional Lagrange's Inversion Theorem
Directory of Open Access Journals (Sweden)
F. A. Abd El-Salam
2013-01-01
Full Text Available Using Riemann-Liouville fractional differential operator, a fractional extension of the Lagrange inversion theorem and related formulas are developed. The required basic definitions, lemmas, and theorems in the fractional calculus are presented. A fractional form of Lagrange's expansion for one implicitly defined independent variable is obtained. Then, a fractional version of Lagrange's expansion in more than one unknown function is generalized. For extending the treatment in higher dimensions, some relevant vectors and tensors definitions and notations are presented. A fractional Taylor expansion of a function of -dimensional polyadics is derived. A fractional -dimensional Lagrange inversion theorem is proved.
Czech Academy of Sciences Publication Activity Database
Šremr, Jiří
2007-01-01
Roč. 132, č. 3 (2007), s. 263-295 ISSN 0862-7959 R&D Projects: GA ČR GP201/04/P183 Institutional research plan: CEZ:AV0Z10190503 Keywords : system of functional differential equations with monotone operators * initial value problem * unique solvability Subject RIV: BA - General Mathematics
Fuminari, Komatsu; Hideki, Atsumi; Manabu, Osakabe; Mitsunori, Matsumae
2015-01-01
We describe a supra-diaphragmatic ectopic pituitary adenoma that was safely removed using the extended endoscopic endonasal approach, and discuss the value of three-dimensional (3D) endoscopy and intra-operative magnetic resonance imaging (MRI) to this type of procedure. A 61-year-old-man with bitemporal hemianopsia was referred to our hospital, where MRI revealed an enhanced suprasellar tumor compressing the optic chiasma. The tumor extended on the planum sphenoidale and partially encased the right internal carotid artery. An endocrinological assessment indicated normal pituitary function. The extended endoscopic endonasal approach was taken using a 3D endoscope in the intraoperative MRI suite. The tumor was located above the diaphragma sellae and separated from the normal pituitary gland. The pathological findings indicated non-functioning pituitary adenoma and thus the tumor was diagnosed as a supra-diaphragmatic ectopic pituitary adenoma. Intra-operative MRI provided useful information to minimize dural opening and the supra-diaphragmatic ectopic pituitary adenoma was removed from the complex neurovascular structure via the extended endoscopic endonasal approach under 3D endoscopic guidance in the intra-operative suite. Safe and effective removal of a supra-diaphragmatic ectopic pituitary adenoma was accomplished via the extended endoscopic endonasal approach with visual information provided by 3D endoscopy and intra-operative MRI.
International Nuclear Information System (INIS)
Tsvetkova, Galina V.; Peddicord, Kenneth L.
2002-01-01
Promising existing nuclear reactor concepts together with new ideas are being discussed worldwide. Many new studies are underway in order to identify prototypes that will be analyzed and developed further as systems for Generation IV. The focus is on designs demonstrating full inherent safety, competitive economics and proliferation resistance. The work discussed here is centered on a modularized small-size High Temperature Gas-cooled Reactor (HTGR) concept. This paper discusses the possibility of maintaining long-term operation on one fuel loading through utilization of plutonium and higher actinides in the small-size pebble-bed reactor (PBR). Acknowledging the well-known flexibility of the PBR design with respect to fuel composition, the principal limitations of the long-term burning of plutonium and higher actinides are considered. The technological challenges and further research are outlined. The results allow the identification of physical features of the PBR that significantly influence flexibility of the design and its applications. (authors)
Observables and Microcospic Entropy of Higher Spin Black Holes
Compère, G.; Jottar, J.I.; Song, W.
2013-01-01
In the context of recently proposed holographic dualities between higher spin theories in AdS3 and (1 + 1)-dimensional CFTs with W symmetry algebras, we revisit the definition of higher spin black hole thermodynamics and the dictionary between bulk fields and dual CFT operators. We build a canonical
Energy Technology Data Exchange (ETDEWEB)
Kwak, Noh Sung; Lee, Jongsoo [Yonsei University, Seoul (Korea, Republic of)
2016-01-15
The present study aims to implement a new selection method and a novel crossover operation in a real-coded genetic algorithm. The proposed selection method facilitates the establishment of a successively evolved population by combining several subpopulations: an elitist subpopulation, an off-spring subpopulation and a mutated subpopulation. A probabilistic crossover is performed based on the measure of probabilistic distance between the individuals. The concept of ‘allowance’ is suggested to describe the level of variance in the crossover operation. A number of nonlinear/non-convex functions and engineering optimization problems are explored to verify the capacities of the proposed strategies. The results are compared with those obtained from other genetic and nature-inspired algorithms.
Inflation from higher dimensions
International Nuclear Information System (INIS)
Shafi, Q.
1987-01-01
We argue that an inflationary phase in the very early universe is related to the transition from a higher dimensional to a four-dimensional universe. We present details of a previously considered model which gives sufficient inflation without fine tuning of parameters. (orig.)
Ghosh, Shubhrangshu
2017-09-01
The correlated and coupled dynamics of accretion and outflow around black holes (BHs) are essentially governed by the fundamental laws of conservation as outflow extracts matter, momentum and energy from the accretion region. Here we analyze a robust form of 2.5-dimensional viscous, resistive, advective magnetized accretion-outflow coupling in BH systems. We solve the complete set of coupled MHD conservation equations self-consistently, through invoking a generalized polynomial expansion in two dimensions. We perform a critical analysis of the accretion-outflow region and provide a complete quasi-analytical family of solutions for advective flows. We obtain the physically plausible outflow solutions at high turbulent viscosity parameter α (≳ 0.3), and at a reduced scale-height, as magnetic stresses compress or squeeze the flow region. We found that the value of the large-scale poloidal magnetic field B P is enhanced with the increase of the geometrical thickness of the accretion flow. On the other hand, differential magnetic torque (-{r}2{\\bar{B}}\\varphi {\\bar{B}}z) increases with the increase in \\dot{M}. {\\bar{B}}{{P}}, -{r}2{\\bar{B}}\\varphi {\\bar{B}}z as well as the plasma beta β P get strongly augmented with the increase in the value of α, enhancing the transport of vertical flux outwards. Our solutions indicate that magnetocentrifugal acceleration plausibly plays a dominant role in effusing out plasma from the radial accretion flow in a moderately advective paradigm which is more centrifugally dominated. However in a strongly advective paradigm it is likely that the thermal pressure gradient would play a more contributory role in the vertical transport of plasma.
Directory of Open Access Journals (Sweden)
Sunday O. Edeki
2018-03-01
Full Text Available In this study, approximate solutions of a system of time-fractional coupled Burger equations were obtained by means of a local fractional operator (LFO in the sense of the Caputo derivative. The LFO technique was built on the basis of the standard differential transform method (DTM. Illustrative examples used in demonstrating the effectiveness and robustness of the proposed method show that the solution method is very efficient and reliable as – unlike the variational iteration method – it does not depend on any process of identifying Lagrange multipliers, even while still maintaining accuracy.
Tavana, Madjid
2003-01-01
The primary driver for developing missions to send humans to other planets is to generate significant scientific return. NASA plans human planetary explorations with an acceptable level of risk consistent with other manned operations. Space exploration risks can not be completely eliminated. Therefore, an acceptable level of cost, technical, safety, schedule, and political risks and benefits must be established for exploratory missions. This study uses a three-dimensional multi-criteria decision making model to identify the risks and benefits associated with three alternative mission architecture operations concepts for the human exploration of Mars identified by the Mission Operations Directorate at Johnson Space Center. The three alternatives considered in this study include split, combo lander, and dual scenarios. The model considers the seven phases of the mission including: 1) Earth Vicinity/Departure; 2) Mars Transfer; 3) Mars Arrival; 4) Planetary Surface; 5) Mars Vicinity/Departure; 6) Earth Transfer; and 7) Earth Arrival. Analytic Hierarchy Process (AHP) and subjective probability estimation are used to captures the experts belief concerning the risks and benefits of the three alternative scenarios through a series of sequential, rational, and analytical processes.
Hara, Shingo; Mitsugi, Masaharu; Kanno, Takahiro; Nomachi, Akihiko; Wajima, Takehiko; Tatemoto, Yukihiro
2013-09-01
This article describes a case we experienced in which good postsurgical facial profiles were obtained for a patient with jaw deformities associated with facial asymmetry, by implementing surgical planning with SimPlant OMS. Using this method, we conducted LF1 osteotomy, intraoral vertical ramus osteotomy (IVRO), sagittal split ramus osteotomy (SSRO), mandibular constriction and mandibular border genioplasty. Not only did we obtain a class I occlusal relationship, but the complicated surgery also improved the asymmetry of the frontal view, as well as of the profile view, of the patient. The virtual operation using three-dimensional computed tomography (3D-CT) could be especially useful for the treatment of patients with jaw deformities associated with facial asymmetry.
Kellerman, A. C.; Shprits, Y.; Kondrashov, D. A.; Podladchikova, T.; Drozdov, A.; Subbotin, D.; Makarevich, R. A.; Donovan, E.; Nagai, T.
2015-12-01
Understanding of the dynamics in Earth's radiation belts is critical to accurate modeling and forecasting of space weather conditions, both which are important for design, and protection of our space-borne assets. In the current study, we utilize the Versatile Electron Radiation Belt (VERB) code, multi-spacecraft measurements, and a split-operator Kalman filter to recontructe the global state of the radiation belt system in the CRRES era and the current era. The reanalysis has revealed a never before seen 4-belt structure in the radiation belts during the March 1991 superstorm, and highlights several important aspects in regards to the the competition between the source, acceleration, loss, and transport of particles. In addition to the above, performing reanalysis in adiabatic coordinates relies on specification of the Earth's magnetic field, and associated observational, and model errors. We determine the observational errors for the Kalman filter directly from cross-spacecraft phase-space density (PSD) conjunctions, and obtain the error in VERB by comparison with reanalysis over a long time period. Specification of errors associated with several magnetic field models provides an important insight into the applicability of such models for radiation belt research. The comparison of CRRES area reanalysis with Van Allen Probe era reanalysis allows us to perform a global comparison of the dynamics of the radiation belts during different parts of the solar cycle and during different solar cycles. The data assimilative model is presently used to perform operational forecasts of the radiation belts (http://rbm.epss.ucla.edu/realtime-forecast/).
International Nuclear Information System (INIS)
McGavin, Dennis G; Tennant, W Craighead
2009-01-01
In setting up a spin Hamiltonian (SH) to study high-spin Zeeman and high-spin nuclear and/or electronic interactions in electron paramagnetic resonance (EPR) experiments, it is argued that a maximally reduced SH (MRSH) framed in tesseral combinations of spherical tensor operators is necessary. Then, the SH contains only those terms that are necessary and sufficient to describe the particular spin system. The paper proceeds then to obtain interrelationships between the parameters of the MRSH and those of alternative SHs expressed in Cartesian tensor and Stevens operator-equivalent forms. The examples taken, initially, are those of Cartesian and Stevens' expressions for high-spin Zeeman terms of dimension BS 3 and BS 5 . Starting from the well-known decomposition of the general Cartesian tensor of second rank to three irreducible tensors of ranks 0, 1 and 2, the decomposition of Cartesian tensors of ranks 4 and 6 are treated similarly. Next, following a generalization of the tesseral spherical tensor equations, the interrelationships amongst the parameters of the three kinds of expressions, as derived from equivalent SHs, are determined and detailed tables, including all redundancy equations, set out. In each of these cases the lowest symmetry, 1-bar Laue class, is assumed and then examples of relationships for specific higher symmetries derived therefrom. The validity of a spin Hamiltonian containing mixtures of terms from the three expressions is considered in some detail for several specific symmetries, including again the lowest symmetry. Finally, we address the application of some of the relationships derived here to seldom-observed low-symmetry effects in EPR spectra, when high-spin electronic and nuclear interactions are present.
Chiral anomalies in higher dimensional supersymmetric theories
International Nuclear Information System (INIS)
Bonora, L.; Pasti, P.; Tonin, M.
1987-01-01
We derive explicit formulas for pure gauge anomalies in a SYM theory in 6D as well as in 10D. Each anomaly consists of two terms: a gauge cocycle and a cocycle of the superdiffeomorphisms. The derivation is based essentially on a remarkable property of supersymmetric theories which we call Weil triviality and is directly connected with the constraints. The analogous problem for Lorentz anomalies is stated in the same way. However, in general, there are difficulties concerning Weil triviality. We prove that for pure SUGRA in 6D as well as in 10D it is possible to prove Weil triviality and, consequently, to obtain explict expressions for pure Lorentz anomalies. However, as far as SUGRA coupled to SYM a la Chapline-Manton or a la Green-Schwarz is concerned, no self-evident solution is available. (orig.)
Huang, Xingfu; Chen, Yanjia; Huang, Zheng; He, Liwei; Liu, Shenrong; Deng, Xiaojiang; Wang, Yongsheng; Li, Rucheng; Xu, Dingli; Peng, Jian
2018-06-01
Several studies have reported the efficacy of a zero-fluoroscopy approach for catheter radiofrequency ablation of arrhythmias in a digital subtraction angiography (DSA) room. However, no reports are available on the ablation of arrhythmias in the absence of DSA in the operating room. To investigate the efficacy and safety of catheter radiofrequency ablation for arrhythmias under the guidance of a Carto 3 three-dimensional (3D) mapping system in an operating room without DSA. Patients were enrolled according to the type of arrhythmia. The Carto 3 mapping system was used to reconstruct heart models and guide the electrophysiologic examination, mapping, and ablation. The total procedure, reconstruction, electrophysiologic examination, and mapping times were recorded. Furthermore, immediate success rates and complications were also recorded. A total of 20 patients were enrolled, including 12 males. The average age was 51.3 ± 17.2 (19-76) years. Nine cases of atrioventricular nodal re-entrant tachycardia, 7 cases of frequent ventricular premature contractions, 3 cases of Wolff-Parkinson-White syndrome, and 1 case of typical atrial flutter were included. All arrhythmias were successfully ablated. The procedure time was 127.0 ± 21.0 (99-177) minutes, the reconstruction time was 6.5 ± 2.9 (3-14) minutes, the electrophysiologic study time was 10.4 ± 3.4 (6-20) minutes, and the mapping time was 11.7 ± 8.3 (3-36) minutes. No complications occurred. Radiofrequency ablation of arrhythmias without DSA is effective and feasible under the guidance of the Carto 3 mapping system. However, the electrophysiology physician must have sufficient experience, and related emergency measures must be present to ensure safety.
Dimensional transition of the universe
International Nuclear Information System (INIS)
Terazawa, Hidezumi.
1989-08-01
In the extended n-dimensional Einstein theory of gravitation, where the spacetime dimension can be taken as a 'dynamical variable' which is determined by the 'Hamilton principle' of minimizing the extended Einstein-Hilbert action, it is suggested that our Universe of four-dimensional spacetime may encounter an astonishing dimensional transition into a new universe of three-dimensional or higher-than-four-dimensional spacetime. (author)
Kholshchev, V. V.
2011-08-01
Failures of steam superheater tubes occurred after the boiler was shifted to operate with a steam temperature of 540°C. The operation of the steam superheater became more reliable after it had been subjected to retrofitting. The modernization scheme is described. An estimate is given to the temperature operating conditions of tubes taking into account the thermal-hydraulic nonuniformity of their heating.
International Nuclear Information System (INIS)
Salvador, F.J.; Gimeno, J.; De la Morena, J.; Carreres, M.
2012-01-01
Highlights: ► Effect of using diesel or biodiesel on injector hydraulic behavior has been analyzed. ► Single and main + post injections have been studied for different injection pressures. ► Higher viscosity affects needle dynamics, especially for low injection pressure. ► The post injection masses are lower for biodiesel fuel despite its higher density. ► Modified injector has been proposed to compensate the differences between the fuels. - Abstract: The influence of using biodiesel fuels on the hydraulic behavior of a solenoid operated common rail injection system has been explored by means of a one-dimensional model. This model has been previously obtained, including a complete characterization of the different components of the injector (mainly the nozzle, the injector holder and the electrovalve), and extensively validated by means of mass flow rate results under different conditions. After that, both single and multiple injection strategies have been analyzed, using a standard diesel fuel and rapeseed methyl ester (RME) as working fluids. Single long injections allowed the characterization of the hydraulic delay of the injector, the needle dynamics and the discharge capability of the couple injector-nozzle for the two fuels considered. Meanwhile, the effect of biodiesel on main plus post injection strategies has been evaluated in several aspects, such as the separation of the two injections or the effect of the main injection on the post injection fueling. Finally, a modification in the injector hardware has been proposed in order to have similar performances using biodiesel as the original injector configuration using standard diesel fuel.
On d -Dimensional Lattice (co)sine n -Algebra
International Nuclear Information System (INIS)
Yao Shao-Kui; Zhang Chun-Hong; Zhao Wei-Zhong; Ding Lu; Liu Peng
2016-01-01
We present the (co)sine n-algebra which is indexed by the d-dimensional integer lattice. Due to the associative operators, this generalized (co)sine n-algebra is the higher order Lie algebra for the n even case. The particular cases are the d-dimensional lattice sine 3 and cosine 5-algebras with the special parameter values. We find that the corresponding d-dimensional lattice sine 3 and cosine 5-algebras are the Nambu 3-algebra and higher order Lie algebra, respectively. The limiting case of the d-dimensional lattice (co)sine n-algebra is also discussed. Moreover we construct the super sine n-algebra, which is the super higher order Lie algebra for the n even case. (paper)
Higher spin fields and the Gelfand-Dickey algebra
International Nuclear Information System (INIS)
Bakas, I.
1989-01-01
We show that in 2-dimensional field theory, higher spin algebras are contained in the algebra of formal pseudodifferential operators introduced by Gelfand and Dickey to describe integrable nonlinear differential equations in Lax form. The spin 2 and 3 algebras are discussed in detail and the generalization to all higher spins is outlined. This provides a conformal field theory approach to the representation theory of Gelfand-Dickey algebras. (orig.)
Malakan Rad, Elaheh; Ghandi, Yazdan; Kocharian, Armen; Mirzaaghayan, Mohammadreza
2016-07-06
Background: The late postoperative course for children with transposition of the great arteries (TGA) with an intact ventricular septum (IVS) is very important because the coronary arteries may be at risk of damage during arterial switch operation (ASO). We sought to investigate left ventricular function in patients with TGA/IVS by echocardiography. Methods: From March 2011 to December 2012, totally 20 infants (12 males and 8 females) with TGA/IVS were evaluated via 2-dimensional speckle-tracking echocardiography (2D STE) more than 6 months after they underwent ASO. A control group of age-matched infants and children was also studied. Left ventricular longitudinal strain (S), strain rate (SR), time to peak systolic longitudinal strain (TPS), and time to peak systolic longitudinal strain rate (TPSR) were measured and compared between the 2 groups. Results: Mean ± SD of age at the time of study in the patients with TGA/IVS was 15 ± 5 months, and also age at the time of ASO was 12 ± 3 days. Weight was 3.13 ± 0.07 kg at birth and 8.83 ± 1.57 kg at the time of ASO. Global strain (S), Time to peak strain rate (TPSR), and Time to peak strain (TPS) were not significantly different between the 2 groups, whereas global strain rate (SR) was significantly different (p value < 0.001). In the 3-chamber view, the values of S in the lateral, septal, inferior, and anteroseptal walls were significantly different between the 2 groups (p value < 0.001), and SR in the posterior wall was significantly different between the 2 groups (p value < 0.001). There were no positive correlations between S and SR in terms of the variables of heart rate, total cardiopulmonary bypass time, and aortic cross-clamp time. There were no statistically significant differences between the 2 groups regarding S, SR, TPS, and TPSR in the anteroseptal and posterior walls in the 3-chamber view and in the lateral and septal walls in the 4-chamber view. Conclusion: We showed that between 6 and 18 months after
An alternative dimensional reduction prescription
International Nuclear Information System (INIS)
Edelstein, J.D.; Giambiagi, J.J.; Nunez, C.; Schaposnik, F.A.
1995-08-01
We propose an alternative dimensional reduction prescription which in respect with Green functions corresponds to drop the extra spatial coordinate. From this, we construct the dimensionally reduced Lagrangians both for scalars and fermions, discussing bosonization and supersymmetry in the particular 2-dimensional case. We argue that our proposal is in some situations more physical in the sense that it maintains the form of the interactions between particles thus preserving the dynamics corresponding to the higher dimensional space. (author). 12 refs
International Nuclear Information System (INIS)
Akiba, Hidenari; Himi, Tetsuo; Hareyama, Masato
2002-01-01
High-resolution computed tomography (HRCT) and magnetic resonance imaging (MRI) have recently become standard pre-operative examinations for cochlear implant candidates. HRCT can demonstrate ossification and narrowing of the cochlea, but subtle calcification or soft tissue obstruction may not be detected by this method alone, and so conventional T2 weighted image (T2WI) on MRI has been recommended to disclose them. In this study, segmental analyses of the cochlea were made on three-dimensional MRI (3DMRI) and HRCT in order to predict cochlear implant difficulties. The study involved 59 consecutive patients with bilateral profound sensorineural hearing loss who underwent MRI and HRCT from November 1992 to February 1998. Etiologies of deafness were meningogenic labyrinthitis (n=9), tympanogenic labyrinthitis (n=12), and others (n=38). Pulse sequence of heavy T2WI was steady state free precession and 3DMRI was reconstructed by maximum intensity projection method. HRCT was reconstructed by bone algorithm focusing on the temporal bone. For alternative segmental analysis, cochleas were anatomically divided into five parts and each of them was classified by three ranks of score depending on 3DMRI or HRCT findings. There was a close correlation by ranks between the total score of the five parts on 3DMRI and HRCT (rs=0.86, P<0.001), and a statistically significant difference was identified between causes of deafness in the total score on 3DMRI or HRCT (P<0.001, respectively). There was a significant difference in the score among the five parts on each examination (P<0.001, respectively), and abnormal findings were more frequent in the inferior horizontal part (IHP) of the basal turn. Of the 35 patients who underwent cochlear implantation, no one had ossification in the IHP on HRCT and only one patient had an obstacle to implantation. When no signal void in the IHP on 3DMRI and no ossification in the IHP on HRCT were assumed to be the criteria for candidacy for cochlear
Three-dimensional surgical simulation.
Cevidanes, Lucia H C; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael
2010-09-01
In this article, we discuss the development of methods for computer-aided jaw surgery, which allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3-dimensional surface models from cone-beam computed tomography, dynamic cephalometry, semiautomatic mirroring, interactive cutting of bone, and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intraoperative guidance. The system provides further intraoperative assistance with a computer display showing jaw positions and 3-dimensional positioning guides updated in real time during the surgical procedure. The computer-aided surgery system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training, and assessing the difficulties of the surgical procedures before the surgery. Computer-aided surgery can make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.
Black Holes in Higher Dimensions
Directory of Open Access Journals (Sweden)
Reall Harvey S.
2008-09-01
Full Text Available We review black-hole solutions of higher-dimensional vacuum gravity and higher-dimensional supergravity theories. The discussion of vacuum gravity is pedagogical, with detailed reviews of Myers–Perry solutions, black rings, and solution-generating techniques. We discuss black-hole solutions of maximal supergravity theories, including black holes in anti-de Sitter space. General results and open problems are discussed throughout.
Charged gravastars in higher dimensions
Energy Technology Data Exchange (ETDEWEB)
Ghosh, S., E-mail: shnkghosh122@gmail.com [Department of Physics, Indian Institute of Engineering Science and Technology, B. Garden, Howrah 711103, West Bengal (India); Rahaman, F., E-mail: rahaman@associates.iucaa.in [Department of Mathematics, Jadavpur University, Kolkata 700032, West Bengal (India); Guha, B.K., E-mail: bkguhaphys@gmail.com [Department of Physics, Indian Institute of Engineering Science and Technology, B. Garden, Howrah 711103, West Bengal (India); Ray, Saibal, E-mail: saibal@associates.iucaa.in [Department of Physics, Government College of Engineering and Ceramic Technology, 73 A.C.B. Lane, Kolkata 700010, West Bengal (India)
2017-04-10
We explore possibility to find out a new model of gravastars in the extended D-dimensional Einstein–Maxwell space–time. The class of solutions as obtained by Mazur and Mottola of a neutral gravastar have been observed as a competent alternative to D-dimensional versions of the Schwarzschild–Tangherlini black hole. The outer region of the charged gravastar model therefore corresponds to a higher dimensional Reissner–Nordström black hole. In connection to this junction conditions, therefore we have formulated mass and the related Equation of State of the gravastar. It has been shown that the model satisfies all the requirements of the physical features. However, overall observational survey of the results also provide probable indication of non-applicability of higher dimensional approach for construction of a gravastar with or without charge from an ordinary 4-dimensional seed as far as physical ground is concerned.
African Journals Online (AJOL)
Kunle Amuwo: Higher Education Transformation: A Paradigm Shilt in South Africa? ... ty of such skills, especially at the middle management levels within the higher ... istics and virtues of differentiation and diversity. .... may be forced to close shop for lack of capacity to attract ..... necessarily lead to racial and gender equity,.
Kranzfelder, Michael; Schneider, Armin; Gillen, Sonja; Feussner, Hubertus
2011-03-01
Technical progress in the operating room (OR) increases constantly, but advanced techniques for error prevention are lacking. It has been the vision to create intelligent OR systems ("autopilot") that not only collect intraoperative data but also interpret whether the course of the operation is normal or deviating from the schedule ("situation awareness"), to recommend the adequate next steps of the intervention, and to identify imminent risky situations. Recently introduced technologies in health care for real-time data acquisition (bar code, radiofrequency identification [RFID], voice and emotion recognition) may have the potential to meet these demands. This report aims to identify, based on the authors' institutional experience and a review of the literature (MEDLINE search 2000-2010), which technologies are currently most promising for providing the required data and to describe their fields of application and potential limitations. Retrieval of information on the functional state of the peripheral devices in the OR is technically feasible by continuous sensor-based data acquisition and online analysis. Using bar code technologies, automatic instrument identification seems conceivable, with information given about the actual part of the procedure and indication of any change in the routine workflow. The dynamics of human activities also comprise key information. A promising technology for continuous personnel tracking is data acquisition with RFID. Emotional data capture and analysis in the OR are difficult. Although technically feasible, nonverbal emotion recognition is difficult to assess. In contrast, emotion recognition by speech seems to be a promising technology for further workflow prediction. The presented technologies are a first step to achieving an increased situational awareness in the OR. However, workflow definition in surgery is feasible only if the procedure is standardized, the peculiarities of the individual patient are taken into account
Williams, D' Ann L; McCormack, Meredith C; Matsui, Elizabeth C; Diette, Gregory B; McKenzie, Shawn E; Geyh, Alison S; Breysse, Patrick N
2016-01-01
Airborne contaminants produced by industrial agricultural facilities contain chemical and biological compounds that can impact the health of residents living in close proximity. Settled dust can be a reservoir for these contaminants and can influence long-term exposures. In this study, we sampled the indoor- and outdoor-settled dust from 40 homes that varied in proximity to industrial-scale dairies (ISD; industrial-scale dairy, a term used in this paper to describe a large dairy farm and adjacent waste sprayfields, concentrated animal feeding operation or animal feeding operation, that uses industrial processes) in the Yakima Valley, Washington. We analyzed settled dust samples for cow allergen (Bos d2, a cow allergen associated with dander, hair, sweat and urine, it is a member of the lipocalin family of allergens associated with mammals), mouse allergen (Mus m1; major mouse allergen, a mouse urinary allergen, in the lipocalin family), dust mite allergens (Der p1 (Dermatophagoides pteronissinus 1) and Der f1 (Dermatophagoides farinae 1)), and endotoxin (a component of the cell walls of gram negative bacteria, lipopolysaccharide, which can be found in air and dust and can produce a strong inflammatory response). A concentration gradient was observed for Bos d2 and endotoxin measured in outdoor-settled dust samples based on proximity to ISD. Indoor-settled dust concentrations of Bos d2 and endotoxin were also highest in proximal homes. While the associated health effects of exposure to cow allergen in settled dust is unknown, endotoxin at concentrations observed in these proximal homes (100 EU/mg) has been associated with increased negative respiratory health effects. These findings document that biological contaminants emitted from ISDs are elevated in indoor- and outdoor-settled dust samples at homes close to these facilities and extend to as much as three miles (4.8 km) away.
International Nuclear Information System (INIS)
Fogel, Mark A.; Weinberg, Paul M.; Hubbard, Anne
2002-01-01
Background: Older patients with transposition of the great arteries who have undergone an atrial inversion procedure (ATRIAL-INV) are difficult to image by echocardiography. The surgical baffles are spatially complex. Objective: To test the hypothesis that two- and three-dimensional MRI can elucidate the spatially complex anatomy in this patient population. Materials and methods; Twelve patients with ATRIAL-INV, ages 16±4.5 years, underwent routine T1-weighted spin-echo axial imaging to obtain a full cardiac volumetric data set. Postprocessing created three-dimensional shaded surface displays and allowed for multiplanar reconstruction. Routine transthoracic echocardiography was available on all patients. Results: Three-dimensional reconstruction enabled complete spatial conceptualization of the venous pathways, and allowed for precise localization of a narrowed region in the upper limb of the systemic venous pathway found in two patients. This was subsequently confirmed on angiography. Routine MRI was able to image the full extent of the venous pathways in all 12 patients. Routine transthoracic echocardiography was able to visualize proximal portions of the venous pathways in eight (67%), the distal upper limb in five (42%), and the distal lower limb in four (33%) patients, and it was able to visualize the outflow tracts in all patients. Conclusion: Three-dimensional reconstruction adds important spatial information, which can be especially important in stenotic regions. Routine MRI is superior to transthoracic echocardiography in delineation of the systemic and pulmonary venous pathway anatomy of ATRIAL-INV patients at mid-term follow-up. Although transesophageal echocardiography is an option, it is more invasive. (orig.)
Two-loop finiteness of self-energies in higher-derivative SQED3
Directory of Open Access Journals (Sweden)
E.A. Gallegos
2015-09-01
Full Text Available In the N=1 superfield formalism, two higher-derivative kinetic operators (Lee–Wick operators are implemented into the standard three dimensional supersymmetric quantum electrodynamics (SQED3 for improving its ultraviolet behavior. It is shown in particular that the ghosts associated with these Lee–Wick operators allow to remove all ultraviolet divergences in the scalar and gauge self-energies at two-loop level.
& Development (LDRD) National Security Education Center (NSEC) Office of Science Programs Richard P Databases National Security Education Center (NSEC) Center for Nonlinear Studies Engineering Institute Scholarships STEM Education Programs Teachers (K-12) Students (K-12) Higher Education Regional Education
International Nuclear Information System (INIS)
Janulyte, A.; Andre, J.; Carette, M.; Mercury, M.; Reynard, C; Zerega, Y.
2009-01-01
A specific Fourier transform operating mode is applied to a 3-dimensional quadrupolar ion trap for mass analysis (Fourier Transform Quadrupolar Ion Trap (FTQIT) Operating Mode or Mass Spectrometer). With this operating mode, an image signal, which is representative of the collective motion of simultaneously confined ions, is made up from a set of recorded time-of-flight histograms. In an ion trap, the secular frequency of ion motion depends on m/Z ratio of the ion. By Fourier transformation of the image signal, one observes the frequency peak of each confined ionic species. When only one ionic species is confined, the peak amplitude is proportional to the maximal amplitude of the image signal. The maximal amplitude of the image signal is expressed according to the operating parameters, the initial conditions of the ions and the number of ions. Simulation tools lead to fluctuation calculation of the maximal amplitude of the image signal. Two origins are explored: (1) the fluctuation of the numbers of ions according to the steady ion flow injection mode (SIFIM) used with this operating mode and (2) the distribution fluctuation of the initial positions and velocities. Initial confinement conditions, obtained with SIFIM injection mode, lead to optimal detection with small fluctuations of the peak amplitude for Fourier transform operating mode applied to an ion trap. (authors)
Fukuda, Hironobu; Imataka, George; Drago, Fabrizio; Maeda, Kosaku; Yoshihara, Shigemi
2017-01-01
We report a case of a 10-year-old female patient who survived ring-sling complex without surgery. The patient had congenital wheezing from the neonatal period and was treated after a tentative diagnosis of infantile asthma. The patient suffered from allergy and was hospitalized several times due to severe wheezing, and when she was 22 months old, she was diagnosed with ring-sling complex. We used a segmental 4 mm internal diameter of the trachea for 3-dimensional computed tomography (3D-CT). ...
Bond, L; Schulz, B; VanMeter, T; Martin, R C G
2017-02-01
Irreversible electroporation (IRE) uses multiple needles and a series of electrical pulses to create pores in cell membranes and cause cell apoptosis. One of the demands of IRE is the precise needle spacing required. Two-dimensional intraoperative ultrasound (2-D iUS) is currently used to measure inter-needle distances but requires significant expertise. This study evaluates the potential of three-dimensional (3-D) image guidance for placing IRE needles and calculating needle spacing. A prospective clinical evaluation of a 3-D needle localization system (Explorer™) was evaluated in consecutive patients from April 2012 through June 2013 for unresectable pancreatic adenocarcinoma. 3-D reconstructions of patients' anatomy were generated from preoperative CT images, which were aligned to the intraoperative space. Thirty consecutive patients with locally advanced pancreatic cancer were treated with IRE. The needle localization system setup added an average of 6.5 min to each procedure. The 3-D needle localization system increased surgeon confidence and ultimately reduced needle placement time. IRE treatment efficacy is highly dependent on accurate needle spacing. The needle localization system evaluated in this study aims to mitigate these issues by providing the surgeon with additional visualization and data in 3-D. The Explorer™ system provides valuable guidance information and inter-needle distance calculations. Copyright © 2016 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.
Hendrickson, Robert M.
This chapter reports 1982 cases involving aspects of higher education. Interesting cases noted dealt with the federal government's authority to regulate state employees' retirement and raised the questions of whether Title IX covers employment, whether financial aid makes a college a program under Title IX, and whether sex segregated mortality…
Supersymmetric dimensional regularization
International Nuclear Information System (INIS)
Siegel, W.; Townsend, P.K.; van Nieuwenhuizen, P.
1980-01-01
There is a simple modification of dimension regularization which preserves supersymmetry: dimensional reduction to real D < 4, followed by analytic continuation to complex D. In terms of component fields, this means fixing the ranges of all indices on the fields (and therefore the numbers of Fermi and Bose components). For superfields, it means continuing in the dimensionality of x-space while fixing the dimensionality of theta-space. This regularization procedure allows the simple manipulation of spinor derivatives in supergraph calculations. The resulting rules are: (1) First do all algebra exactly as in D = 4; (2) Then do the momentum integrals as in ordinary dimensional regularization. This regularization procedure needs extra rules before one can say that it is consistent. Such extra rules needed for superconformal anomalies are discussed. Problems associated with renormalizability and higher order loops are also discussed
Ladson, Charles L.; Ray, Edward J.
1987-01-01
Presented is a review of the development of the world's first cryogenic pressure tunnel, the Langley 0.3-Meter Transonic Cryogenic Tunnel (0.3-m TCT). Descriptions of the instrumentation, data acquisition systems, and physical features of the two-dimensional 8- by 24-in, (20.32 by 60.96 cm) and advanced 13- by 13-in (33.02 by 33.02 cm) adaptive-wall test-section inserts of the 0.3-m TCT are included. Basic tunnel-empty Mach number distributions, stagnation temperature distributions, and power requirements are included. The Mach number capability of the facility is from about 0.20 to 0.90. Stagnation pressure can be varied from about 80 to 327 K.
International Nuclear Information System (INIS)
Coic, P.
1984-01-01
The principle of a cooling tower is first presented. The equations of the problem are given; the modeling of load losses and heat transfer is described. Then, the numerical method based on a finite difference discrete method is described. Finally, the different results of the calculations carried out in the case of an industrial operation are presented [fr
Operators and higher genus mirror curves
Energy Technology Data Exchange (ETDEWEB)
Codesido, Santiago [Département de Physique Théorique et section de Mathématiques,Université de Genève,Genève, CH-1211 (Switzerland); Gu, Jie [Laboratoire de Physique Théorique de l’École Normale Supérieure,CNRS, PSL Research University,Sorbonne Universités, UPMC, 75005 Paris (France); Mariño, Marcos [Département de Physique Théorique et section de Mathématiques,Université de Genève,Genève, CH-1211 (Switzerland)
2017-02-17
We perform further tests of the correspondence between spectral theory and topological strings, focusing on mirror curves of genus greater than one with nontrivial mass parameters. In particular, we analyze the geometry relevant to the SU(3) relativistic Toda lattice, and the resolved ℂ{sup 3}/ℤ{sub 6} orbifold. Furthermore, we give evidence that the correspondence holds for arbitrary values of the mass parameters, where the quantization problem leads to resonant states. We also explore the relation between this correspondence and cluster integrable systems.
Yamaguchi, Satoshi; Yamada, Yuya; Yoshida, Yoshinori; Noborio, Hiroshi; Imazato, Satoshi
2012-01-01
The virtual reality (VR) simulator is a useful tool to develop dental hand skill. However, VR simulations with reactions of patients have limited computational time to reproduce a face model. Our aim was to develop a patient face model that enables real-time collision detection and cutting operation by using stereolithography (STL) and deterministic finite automaton (DFA) data files. We evaluated dependence of computational cost and constructed the patient face model using the optimum condition for combining STL and DFA data files, and assessed the computational costs for operation in do-nothing, collision, cutting, and combination of collision and cutting. The face model was successfully constructed with low computational costs of 11.3, 18.3, 30.3, and 33.5 ms for do-nothing, collision, cutting, and collision and cutting, respectively. The patient face model could be useful for developing dental hand skill with VR.
Fukuda, Hironobu; Imataka, George; Drago, Fabrizio; Maeda, Kosaku; Yoshihara, Shigemi
2017-09-01
We report a case of a 10-year-old female patient who survived ring-sling complex without surgery. The patient had congenital wheezing from the neonatal period and was treated after a tentative diagnosis of infantile asthma. The patient suffered from allergy and was hospitalized several times due to severe wheezing, and when she was 22 months old, she was diagnosed with ring-sling complex. We used a segmental 4 mm internal diameter of the trachea for 3-dimensional computed tomography (3D-CT). Bronchial asthma is considered an exacerbating factor in infantile period and frequently required treatment with bronchodilator. After the age of 10, the patient had recurrent breathing difficulties during physical activity and during night time, and this condition was assessed to be related to the pressure from the blood vessel on the ring. We repeated the 3D-CT evaluation later and discovered that the internal diameter of the trachea had grown to 5 mm. Eventually, patient's breathing difficulties disappeared after the treatment of bronchial asthma and restriction of physical activities. Our patient remained in stable condition without undergoing any surgical procedures even after she passed the age of 10.
International Nuclear Information System (INIS)
Sharma, D.; Feng, Y.; Sardei, F.; Reiter, D.
2005-01-01
This paper presents self-consistent three-dimensional (3D) plasma transport simulations in the boundary of stellarator W7-X obtained with the Monte Carlo code EMC3-EIRENE for three typical island divertor configurations. The chosen 3D grid consists of relatively simple nested finite toroidal surfaces defined on a toroidal field period and covering the whole edge topology, which includes closed surfaces, islands and ergodic regions. Local grid refinements account for the required high resolution in the divertor region. The distribution of plasma density and temperature in the divertor region, as well as the power deposition profiles on the divertor plates, are shown to strongly depend on the island geometry, i.e. on the position and size of the dominant island chain. Configurations with strike-point positions closer to the gap of the divertor chamber generally favour the neutral compression in the divertor chamber and hence the pumping efficiency. The ratio of pumping to recycling fluxes is found to be roughly independent of the separatrix density and is thus a figure of merit for the quality of the configuration and of the divertor system in terms of density control. Lower limits for the achievable separatrix density, which determine the particle exhaust capabilities in stationary conditions, are compared for the three W7-X configurations
Efficient construction of two-dimensional cluster states with probabilistic quantum gates
International Nuclear Information System (INIS)
Chen Qing; Cheng Jianhua; Wang Kelin; Du Jiangfeng
2006-01-01
We propose an efficient scheme for constructing arbitrary two-dimensional (2D) cluster states using probabilistic entangling quantum gates. In our scheme, the 2D cluster state is constructed with starlike basic units generated from 1D cluster chains. By applying parallel operations, the process of generating 2D (or higher-dimensional) cluster states is significantly accelerated, which provides an efficient way to implement realistic one-way quantum computers
z -Weyl gravity in higher dimensions
Energy Technology Data Exchange (ETDEWEB)
Moon, Taeyoon; Oh, Phillial, E-mail: dpproject@skku.edu, E-mail: ploh@skku.edu [Department of Physics and Institute of Basic Science, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)
2017-09-01
We consider higher dimensional gravity in which the four dimensional spacetime and extra dimensions are not treated on an equal footing. The anisotropy is implemented in the ADM decomposition of higher dimensional metric by requiring the foliation preserving diffeomorphism invariance adapted to the extra dimensions, thus keeping the general covariance only for the four dimensional spacetime. The conformally invariant gravity can be constructed with an extra (Weyl) scalar field and a real parameter z which describes the degree of anisotropy of conformal transformation between the spacetime and extra dimensional metrics. In the zero mode effective 4D action, it reduces to four-dimensional scalar-tensor theory coupled with nonlinear sigma model described by extra dimensional metrics. There are no restrictions on the value of z at the classical level and possible applications to the cosmological constant problem with a specific choice of z are discussed.
Higher spin black holes with soft hair
Energy Technology Data Exchange (ETDEWEB)
Grumiller, Daniel [Institute for Theoretical Physics, TU Wien,Wiedner Hauptstrasse 8-10/136, Vienna, A-1040 (Austria); Pérez, Alfredo [Centro de Estudios Científicos (CECs),Av. Arturo Prat 514, Valdivia (Chile); Prohazka, Stefan [Institute for Theoretical Physics, TU Wien,Wiedner Hauptstrasse 8-10/136, Vienna, A-1040 (Austria); Tempo, David; Troncoso, Ricardo [Centro de Estudios Científicos (CECs),Av. Arturo Prat 514, Valdivia (Chile)
2016-10-21
We construct a new set of boundary conditions for higher spin gravity, inspired by a recent “soft Heisenberg hair”-proposal for General Relativity on three-dimensional Anti-de Sitter space. The asymptotic symmetry algebra consists of a set of affine û(1) current algebras. Its associated canonical charges generate higher spin soft hair. We focus first on the spin-3 case and then extend some of our main results to spin-N, many of which resemble the spin-2 results: the generators of the asymptotic W{sub 3} algebra naturally emerge from composite operators of the û(1) charges through a twisted Sugawara construction; our boundary conditions ensure regularity of the Euclidean solutions space independently of the values of the charges; solutions, which we call “higher spin black flowers”, are stationary but not necessarily spherically symmetric. Finally, we derive the entropy of higher spin black flowers, and find that for the branch that is continuously connected to the BTZ black hole, it depends only on the affine purely gravitational zero modes. Using our map to W-algebra currents we recover well-known expressions for higher spin entropy. We also address higher spin black flowers in the metric formalism and achieve full consistency with previous results.
Multi dimensional analysis of Design Basis Events using MARS-LMR
International Nuclear Information System (INIS)
Woo, Seung Min; Chang, Soon Heung
2012-01-01
Highlights: ► The one dimensional analyzed sodium hot pool is modified to a three dimensional node system, because the one dimensional analysis cannot represent the phenomena of the inside pool of a big size pool with many compositions. ► The results of the multi-dimensional analysis compared with the one dimensional analysis results in normal operation, TOP (Transient of Over Power), LOF (Loss of Flow), and LOHS (Loss of Heat Sink) conditions. ► The difference of the sodium flow pattern due to structure effect in the hot pool and mass flow rates in the core lead the different sodium temperature and temperature history under transient condition. - Abstract: KALIMER-600 (Korea Advanced Liquid Metal Reactor), which is a pool type SFR (Sodium-cooled Fast Reactor), was developed by KAERI (Korea Atomic Energy Research Institute). DBE (Design Basis Events) for KALIMER-600 has been analyzed in the one dimension. In this study, the one dimensional analyzed sodium hot pool is modified to a three dimensional node system, because the one dimensional analysis cannot represent the phenomena of the inside pool of a big size pool with many compositions, such as UIS (Upper Internal Structure), IHX (Intermediate Heat eXchanger), DHX (Decay Heat eXchanger), and pump. The results of the multi-dimensional analysis compared with the one dimensional analysis results in normal operation, TOP (Transient of Over Power), LOF (Loss of Flow), and LOHS (Loss of Heat Sink) conditions. First, the results in normal operation condition show the good agreement between the one and multi-dimensional analysis. However, according to the sodium temperatures of the core inlet, outlet, the fuel central line, cladding and PDRC (Passive Decay heat Removal Circuit), the temperatures of the one dimensional analysis are generally higher than the multi-dimensional analysis in conditions except the normal operation state, and the PDRC operation time in the one dimensional analysis is generally longer than
Directory of Open Access Journals (Sweden)
Akimov Pavel Alekseevich
2012-10-01
Full Text Available The proposed paper covers the operator-related formulation of the eigenvalue problem of analysis of a three-dimensional structure that has piecewise-constant physical and geometrical parameters alongside the so-called basic direction within the framework of a discrete-continual approach (a discrete-continual finite element method, a discrete-continual variation method. Generally, discrete-continual formulations represent contemporary mathematical models that become available for computer implementation. They make it possible for a researcher to consider the boundary effects whenever particular components of the solution represent rapidly varying functions. Another feature of discrete-continual methods is the absence of any limitations imposed on lengths of structures. The three-dimensional problem of elasticity is used as the design model of a structure. In accordance with the so-called method of extended domain, the domain in question is embordered by an extended one of an arbitrary shape. At the stage of numerical implementation, relative key features of discrete-continual methods include convenient mathematical formulas, effective computational patterns and algorithms, simple data processing, etc. The authors present their formulation of the problem in question for an isotropic medium with allowance for supports restrained by elastic elements while standard boundary conditions are also taken into consideration.
Indian Academy of Sciences (India)
Dimensional analysis is a useful tool which finds important applications in physics and engineering. It is most effective when there exist a maximal number of dimensionless quantities constructed out of the relevant physical variables. Though a complete theory of dimen- sional analysis was developed way back in 1914 in a.
International Nuclear Information System (INIS)
Nadkarni, S.K.; Drangova, M.; Boughner, D.R.; Fenster, A.; Department of Medical Biophysics, Medical Sciences Building, University of Western Ontario, London, Ontario N6A 5C1
2000-01-01
Accurate left ventricular (LV) volume and mass estimation is a strong predictor of cardiovascular morbidity and mortality. We propose that our technique of 3D echocardiography provides an accurate quantification of LV volume and mass by the reconstruction of 2D images into 3D volumes, thus avoiding the need for geometric assumptions. We compared the accuracy and variability in LV volume and mass measurement using 3D echocardiography with 2D echocardiography, using in vitro studies. Six operators measured the LV volume and mass of seven porcine hearts, using both 3D and 2D techniques. Regression analysis was used to test the accuracy of results and an ANOVA test was used to compute variability in measurement. LV volume measurement accuracy was 9.8% (3D) and 18.4% (2D); LV mass measurement accuracy was 5% (3D) and 9.2% (2D). Variability in LV volume quantification with 3D echocardiography was %SEM inter = 13.5%, %SEM intra = 11.4%, and for 2D echocardiography was %SEM inter = 21.5%, %SEM intra = 19.1%. We derived an equation to predict uncertainty in measurement of LV volume and mass using 3D echocardiography, the results of which agreed with our experimental results to within 13%. 3D echocardiography provided twice the accuracy for LV volume and mass measurement and half the variability for LV volume measurement as compared with 2D echocardiography. (author)
Seesaw neutrino masses with large mixings from dimensional deconstruction
International Nuclear Information System (INIS)
Balaji, K.R.S.; Lindner, Manfred; Seidl, Gerhart
2003-01-01
We demonstrate a dynamical origin for the dimension-five seesaw operator in dimensional deconstruction models. Light neutrino masses arise from the seesaw scale which corresponds to the inverse lattice spacing. It is shown that the deconstructing limit naturally prefers maximal leptonic mixing. Higher-order corrections which are allowed by gauge invariance can transform the bimaximal into a bilarge mixing. These terms may appear to be nonrenormalizable at scales smaller than the deconstruction scale
Higher holonomies: comparing two constructions
DEFF Research Database (Denmark)
Schaetz, Florian; Arias Abad, Camilo
2015-01-01
, there are the higher holonomies associated with flat superconnections as studied by Igusa [7], Block–Smith [3] and Arias Abad–Schätz [1]. We first explain how by truncating the latter construction one obtains examples of the former. Then we prove that the two-dimensional holonomies provided by the two approaches...
Energy Technology Data Exchange (ETDEWEB)
Martinc, R; Sotic, O; Skoric, M; Cupac, S; Bulovic, V; Maric, I; Marinkov, L [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)
1980-10-15
Highly enriched (80%) uranium oxide fuel was regularly used in the mixed reactor core with the 2% enriched fuel since 1976. The most important changes related to reactor operation, in comparison with the original design project were related to reactor core fuelling schemes. At the end of 1979 reactor was shutdown due to the corrosion coating noticed on some fuel elements and due to decrease quality of the heavy water. Subsequently the Sanitary inspector of Serbia has prohibited further reactor operation. Restart of the reactor will not be a simple continuation of operation. It is indispensable to perform complete experimental program including measurements of critical parameters at different power levels for the core with fresh 80% enriched fuel. The aim of this document is to obtain working permission and its contents are in agreement with the procedure demanded by the Safety Committee of the Institute. It includes results of optimization and safety analysis for the initial reactor core. Since the permission for restart is not obtained, a separate RA reactor safety report is prepared in addition to the program for experimental operation. This report includes: detailed program for reactor experimental operation with 80% enriched fuel in the core at low power levels, and contents of the experimental operation with 80% enriched fuel in the core at higher power levels. [Serbo-Croat] Od decembra 1976. godine redovno je korisceno 80% obogaceno gorivo u mesanoj resetki reaktorskog jezgra sa 2% obogacenim gorivom. Najvece izmene na reaktoru u odnosu na originalni projekat izvrsene su u nacinu rukovanja gorivom. Krajem marta 1979. godine obustavljen je rad reaktora usled naslaga na gorivnim elementima i loseg stanja teske vode. Naknadno je izdata zabrana za rad reaktora od strane Sanitarnog inspektora SR Srbije. Ponovno pustanje reaktora u rad nece biti jednostavan nastavak rada. Neophodno je da se izvede kompletan program merenja kriticnih parametara i drugih
Improved variational estimates for the mass gap in the 2-dimensional XY-model
International Nuclear Information System (INIS)
Patkos, A.; Hari Dass, N.D.
1982-07-01
The variational estimate obtained recently for the mass gap of the 2-dimensional XY-model is improved by extending the treatment to higher powers of the transfer operator. The relativistic dispersion relation for single particle states of low momentum is also verified. (Auth.)
Three New (2+1)-dimensional Integrable Systems and Some Related Darboux Transformations
Guo, Xiu-Rong
2016-06-01
We introduce two operator commutators by using different-degree loop algebras of the Lie algebra A1, then under the framework of zero curvature equations we generate two (2+1)-dimensional integrable hierarchies, including the (2+1)-dimensional shallow water wave (SWW) hierarchy and the (2+1)-dimensional Kaup-Newell (KN) hierarchy. Through reduction of the (2+1)-dimensional hierarchies, we get a (2+1)-dimensional SWW equation and a (2+1)-dimensional KN equation. Furthermore, we obtain two Darboux transformations of the (2+1)-dimensional SWW equation. Similarly, the Darboux transformations of the (2+1)-dimensional KN equation could be deduced. Finally, with the help of the spatial spectral matrix of SWW hierarchy, we generate a (2+1) heat equation and a (2+1) nonlinear generalized SWW system containing inverse operators with respect to the variables x and y by using a reduction spectral problem from the self-dual Yang-Mills equations. Supported by the National Natural Science Foundation of China under Grant No. 11371361, the Shandong Provincial Natural Science Foundation of China under Grant Nos. ZR2012AQ011, ZR2013AL016, ZR2015EM042, National Social Science Foundation of China under Grant No. 13BJY026, the Development of Science and Technology Project under Grant No. 2015NS1048 and A Project of Shandong Province Higher Educational Science and Technology Program under Grant No. J14LI58
Gauge-Higgs unification in higher dimensions
International Nuclear Information System (INIS)
Hall, Lawrence; Nomura, Yasunori; Smith, David
2002-01-01
The electroweak Higgs doublets are identified as components of a vector multiplet in a higher-dimensional supersymmetric field theory. We construct a minimal model in 6D where the electroweak SU(2)xU(1) gauge group is extended to SU(3), and unified 6D models with the unified SU(5) gauge symmetry extended to SU(6). In these realistic theories the extended gauge group is broken by orbifold boundary conditions, leaving Higgs doublet zero modes which have Yukawa couplings to quarks and leptons on the orbifold fixed points. In one SU(6) model the weak mixing angle receives power law corrections, while in another the fixed point structure forbids such corrections. A 5D model is also constructed in which the Higgs doublet contains the fifth component of the gauge field. In this case Yukawa couplings are introduced as nonlocal operators involving the Wilson line of this gauge field
International Nuclear Information System (INIS)
Ambjoern, J.; Bellini, A.; Johnston, D.
1990-10-01
It is clear from both the non-perturbative and perturbative approaches to two-dimensional quantum gravity that a new strong coupling regime is setting in at d=1, independent of the genus of the worldsheet being considered. It has been suggested that a Kosterlitz-Thouless (KT) phase transition in the Liouville theory is the cause of this behaviour. However, it has recently been pointed out that the XY model, which displays a KT transition on the plane and the sphere, is always in the strong coupling, disordered phase on a surface of constant negative curvature. A higher genus worldsheet can be represented as a fundamental region on just such a surface, which might seem to suggest that the KT picture predicts a strong coupling region for arbitrary d, contradicting the known results. We resolve the apparent paradox. (orig.)
Dimensional reduction in anomaly mediation
International Nuclear Information System (INIS)
Boyda, Ed; Murayama, Hitoshi; Pierce, Aaron
2002-01-01
We offer a guide to dimensional reduction in theories with anomaly-mediated supersymmetry breaking. Evanescent operators proportional to ε arise in the bare Lagrangian when it is reduced from d=4 to d=4-2ε dimensions. In the course of a detailed diagrammatic calculation, we show that inclusion of these operators is crucial. The evanescent operators conspire to drive the supersymmetry-breaking parameters along anomaly-mediation trajectories across heavy particle thresholds, guaranteeing the ultraviolet insensitivity
International Nuclear Information System (INIS)
Feinsilver, Philip; Schott, Rene
2009-01-01
We discuss topics related to finite-dimensional calculus in the context of finite-dimensional quantum mechanics. The truncated Heisenberg-Weyl algebra is called a TAA algebra after Tekin, Aydin and Arik who formulated it in terms of orthofermions. It is shown how to use a matrix approach to implement analytic representations of the Heisenberg-Weyl algebra in univariate and multivariate settings. We provide examples for the univariate case. Krawtchouk polynomials are presented in detail, including a review of Krawtchouk polynomials that illustrates some curious properties of the Heisenberg-Weyl algebra, as well as presenting an approach to computing Krawtchouk expansions. From a mathematical perspective, we are providing indications as to how to implement infinite terms Rota's 'finite operator calculus'.
On higher-spin supertranslations and superrotations
Energy Technology Data Exchange (ETDEWEB)
Campoleoni, Andrea [Université Libre de Bruxelles and International Solvay Institutes,ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Francia, Dario; Heissenberg, Carlo [Scuola Normale Superiore and INFN,Piazza dei Cavalieri 7, I-56126 Pisa (Italy)
2017-05-22
We study the large gauge transformations of massless higher-spin fields in four-dimensional Minkowski space. Upon imposing suitable fall-off conditions, providing higher-spin counterparts of the Bondi gauge, we observe the existence of an infinite-dimensional asymptotic symmetry algebra. The corresponding Ward identities can be held responsible for Weinberg’s factorisation theorem for amplitudes involving soft particles of spin greater than two.
Competitiveness - higher education
Directory of Open Access Journals (Sweden)
Labas Istvan
2016-03-01
Full Text Available Involvement of European Union plays an important role in the areas of education and training equally. The member states are responsible for organizing and operating their education and training systems themselves. And, EU policy is aimed at supporting the efforts of member states and trying to find solutions for the common challenges which appear. In order to make our future sustainable maximally; the key to it lies in education. The highly qualified workforce is the key to development, advancement and innovation of the world. Nowadays, the competitiveness of higher education institutions has become more and more appreciated in the national economy. In recent years, the frameworks of operation of higher education systems have gone through a total transformation. The number of applying students is continuously decreasing in some European countries therefore only those institutions can “survive” this shortfall, which are able to minimize the loss of the number of students. In this process, the factors forming the competitiveness of these budgetary institutions play an important role from the point of view of survival. The more competitive a higher education institution is, the greater the chance is that the students would like to continue their studies there and thus this institution will have a greater chance for the survival in the future, compared to ones lagging behind in the competition. Aim of our treatise prepared is to present the current situation and main data of the EU higher education and we examine the performance of higher education: to what extent it fulfils the strategy for smart, sustainable and inclusive growth which is worded in the framework of Europe 2020 programme. The treatise is based on analysis of statistical data.
Effective operators in SUSY, superfield constraints and searches for a UV completion
Dudas, E.
2015-01-01
We discuss the role of a class of higher dimensional operators in 4D N=1 supersymmetric effective theories. The Lagrangian in such theories is an expansion in momenta below the scale of "new physics" ($\\Lambda$) and contains the effective operators generated by integrating out the "heavy states" above $\\Lambda$ present in the UV complete theory. We go beyond the "traditional" leading order in this momentum expansion (in $\\partial/\\Lambda$). Keeping manifest supersymmetry and using superfield {\\it constraints} we show that the corresponding higher dimensional (derivative) operators in the sectors of chiral, linear and vector superfields of a Lagrangian can be "unfolded" into second-order operators. The "unfolded" formulation has only polynomial interactions and additional massive superfields, some of which are ghost-like if the effective operators were {\\it quadratic} in fields. Using this formulation, the UV theory emerges naturally and fixes the (otherwise unknown) coefficient and sign of the initial (higher...
Cosmic censorship in higher dimensions
International Nuclear Information System (INIS)
Goswami, Rituparno; Joshi, Pankaj S.
2004-01-01
We show that the naked singularities arising in dust collapse from smooth initial data (which include those discovered by Eardley and Smarr, Christodoulou, and Newman) are removed when we make a transition to higher dimensional spacetimes. Cosmic censorship is then restored for dust collapse, which will always produce a black hole as the collapse end state for dimensions D≥6, under conditions to be motivated physically such as the smoothness of initial data from which the collapse develops
International Nuclear Information System (INIS)
Sonoda, Hidenori
1992-01-01
We give a formula for the derivatives of a correlation function of composite operators with respect to the parameters (i.e. the strong fine structure constant and the quark mass) of QCD in four- dimensional euclidean space. The formula is given as spatial integration of the operator conjugate to a parameter. The operator product of a composite operator and a conjugate operator has an unintegrable part, and the formula requires divergent subtractions. By imposing consistency conditions we drive a relation between the anomalous dimensions of the composite operators and the unintegrable part of the operator product coefficients. (orig.)
Light higgsinos as heralds of higher-dimensional unification
International Nuclear Information System (INIS)
Bruemmer, F.; Buchmueller, W.
2011-05-01
Grand-unified models with extra dimensions at the GUT scale will typically contain exotic states with Standard Model charges and GUT-scale masses. They can act as messengers for gauge-mediated supersymmetry breaking. If the number of messengers is sizeable, soft terms for the visible sector fields will be predominantly generated by gauge mediation, while gravity mediation can induce a small μ parameter. We illustrate this hybrid mediation pattern with two examples, in which the superpartner spectrum contains light and near-degenerate higgsinos with masses below 200 GeV. The typical masses of all other superpartners are much larger, from at least 500 GeV up to several TeV. The lightest superparticle is the gravitino, which may be the dominant component of dark matter. (orig.)
Exploring Higher Dimensional Black Holes at the Large Hadron Collider
Harris, C M; Parker, M A; Richardson, P; Sabetfakhri, A; Webber, Bryan R
2005-01-01
In some extra dimension theories with a TeV fundamental Planck scale, black holes could be produced in future collider experiments. Although cross sections can be large, measuring the model parameters is difficult due to the many theoretical uncertainties. Here we discuss those uncertainties and then we study the experimental characteristics of black hole production and decay at a typical detector using the ATLAS detector as a guide. We present a new technique for measuring the temperature of black holes that applies to many models. We apply this technique to a test case with four extra dimensions and, using an estimate of the parton-level production cross section error of 20\\%, determine the Planck mass to 15\\% and the number of extra dimensions to $\\pm$0.75.
Exploring higher dimensional black holes at the Large Hadron Collider
International Nuclear Information System (INIS)
Harris, Christopher M.; Palmer, Matthew J.; Parker, Michael A.; Richardson, Peter; Sabetfakhri, Ali; Webber, Bryan R.
2005-01-01
In some extra dimension theories with a TeV fundamental Planck scale, black holes could be produced in future collider experiments. Although cross sections can be large, measuring the model parameters is difficult due to the many theoretical uncertainties. Here we discuss those uncertainties and then we study the experimental characteristics of black hole production and decay at a typical detector using the ATLAS detector as a guide. We present a new technique for measuring the temperature of black holes that applies to many models. We apply this technique to a test case with four extra dimensions and, using an estimate of the parton-level production cross section error of 20%, determine the Planck mass to 15% and the number of extra dimensions to ±0.75
Higher-dimensional string theory in Lyra geometry
Indian Academy of Sciences (India)
Cosmic strings as source of gravitational field in general relativity was discussed by ... tensor theory of gravitation and constructed an analog of Einstein field ... As string concept is useful before the particle creation and can explain galaxy for-.
Higher-dimensional cosmological model with variable gravitational ...
Indian Academy of Sciences (India)
variable G and bulk viscosity in Lyra geometry. Exact solutions for ... a comparative study of Robertson–Walker models with a constant deceleration .... where H is defined as H =(˙A/A)+(1/3)( ˙B/B) and β0,H0 are representing present values of β ...
GUT precursors and fixed points in higher-dimensional theories
Indian Academy of Sciences (India)
that it is possible to construct self-consistent 'hybrid' models containing ... states associated with the emergence of a grand unified theory (GUT) at this en- .... However, even though these couplings are extremely weak, the true loop expansion.
Simplicial models for trace spaces II: General higher dimensional automata
DEFF Research Database (Denmark)
Raussen, Martin
of directed paths with given end points in a pre-cubical complex as the nerve of a particular category. The paper generalizes the results from Raussen [19, 18] in which we had to assume that the HDA in question arises from a semaphore model. In particular, important for applications, it allows for models...
Higher dimensional unitary braid matrices: Construction, associated structures and entanglements
International Nuclear Information System (INIS)
Abdesselam, B.; Chakrabarti, A.; Dobrev, V.K.; Mihov, S.G.
2007-03-01
We construct (2n) 2 x (2n) 2 unitary braid matrices R-circumflex for n ≥ 2 generalizing the class known for n = 1. A set of (2n) x (2n) matrices (I, J,K,L) are defined. R-circumflex is expressed in terms of their tensor products (such as K x J), leading to a canonical formulation for all n. Complex projectors P ± provide a basis for our real, unitary R-circumflex. Baxterization is obtained. Diagonalizations and block- diagonalizations are presented. The loss of braid property when R-circumflex (n > 1) is block-diagonalized in terms of R-circumflex (n = 1) is pointed out and explained. For odd dimension (2n + 1) 2 x (2n + 1) 2 , a previously constructed braid matrix is complexified to obtain unitarity. R-circumflexLL- and R-circumflexTT- algebras, chain Hamiltonians, potentials for factorizable S-matrices, complex non-commutative spaces are all studied briefly in the context of our unitary braid matrices. Turaev construction of link invariants is formulated for our case. We conclude with comments concerning entanglements. (author)
Light higgsinos as heralds of higher-dimensional unification
Energy Technology Data Exchange (ETDEWEB)
Bruemmer, F.; Buchmueller, W.
2011-05-15
Grand-unified models with extra dimensions at the GUT scale will typically contain exotic states with Standard Model charges and GUT-scale masses. They can act as messengers for gauge-mediated supersymmetry breaking. If the number of messengers is sizeable, soft terms for the visible sector fields will be predominantly generated by gauge mediation, while gravity mediation can induce a small {mu} parameter. We illustrate this hybrid mediation pattern with two examples, in which the superpartner spectrum contains light and near-degenerate higgsinos with masses below 200 GeV. The typical masses of all other superpartners are much larger, from at least 500 GeV up to several TeV. The lightest superparticle is the gravitino, which may be the dominant component of dark matter. (orig.)
Extensions of three-dimensional higher-derivative gravity
Yin, Yihao
2013-01-01
Driedimensionale zwaartekrachtmodellen met hogere afgeleiden, met in het bijzonder New Massive Gravity (NMG) en Topologically Massive Gravity (TMG), zijn speelmodellen die gebruikt worden door theoretische natuurkundigen om te onderzoeken hoe Einsteins algemene relativiteitstheorie verbeterd kan
Higher Dimensional Mappings for Which the Area Formula Holds
Goffman, Casper; Ziemer, William P.
1970-01-01
For each continuous mapping of 2 space into n space, n ≥ 2, the Lebesgue area is given by the classical formula provided that the partial derivatives exist almost everywhere and belong to the class L2. The analogous question for mappings of m space into n space, 2 < m ≤ n, has been open for a long time. We answer this question in the affirmative in a more general setting. Accordingly, as a special case, we show that if a continuous mapping of m space into n space, m ≤ n, has partial derivatives which belong to Lm then the Lebesgue area is given by the classical formula. PMID:16591817
Charged fluid distribution in higher dimensional spheroidal space-time
Indian Academy of Sciences (India)
associated 3-spaces obtained as hypersurfaces t = constant, 3-spheroids, are suit- ... pressure. Considering the Vaidya–Tikekar [12] spheroidal geometry, ... a relativistic star in hydrostatic equilibrium having the spheroidal geometry of the .... K = 1, the spheroidal 3-space degenerates into a flat 3-space and when K = 0 it.
Pontrjagin, Lev Semenovič
1984-01-01
Lev Semenovic Pontrjagin (1908) is one of the outstanding figures in 20th century mathematics. In a long career he has made fundamental con tributions to many branches of mathematics, both pure and applied. He has received every honor that a grateful government can bestow. Though in no way constrained to do so, he has through the years taught mathematics courses at Moscow State University. In the year 1975 he set himself the task of writing a series of books on secondary school and beginning university mathematics. In his own words, "I wished to set forth the foundations of higher mathematics in a form that would have been accessible to myself as a lad, but making use of all my experience as a scientist and a teacher, ac cumulated over many years. " The present volume is a translation of the first two out of four moderately sized volumes on this theme planned by Pro fessor Pontrjagin. The book begins at the beginning of modern mathematics, analytic ge ometry in the plane and 3-dimensional space. Refin...
Gravitating multidefects from higher dimensions
Giovannini, Massimo
2007-01-01
Warped configurations admitting pairs of gravitating defects are analyzed. After devising a general method for the construction of multidefects, specific examples are presented in the case of higher-dimensional Einstein-Hilbert gravity. The obtained profiles describe diverse physical situations such as (topological) kink-antikink systems, pairs of non-topological solitons and bound configurations of a kink and of a non-topological soliton. In all the mentioned cases the geometry is always well behaved (all relevant curvature invariants are regular) and tends to five-dimensional anti-de Sitter space-time for large asymptotic values of the bulk coordinate. Particular classes of solutions can be generalized to the framework where the gravity part of the action includes, as a correction, the Euler-Gauss-Bonnet combination. After scrutinizing the structure of the zero modes, the obtained results are compared with conventional gravitating configurations containing a single topological defect.
Coset space dimensional reduction of gauge theories
Energy Technology Data Exchange (ETDEWEB)
Kapetanakis, D. (Physik Dept., Technische Univ. Muenchen, Garching (Germany)); Zoupanos, G. (CERN, Geneva (Switzerland))
1992-10-01
We review the attempts to construct unified theories defined in higher dimensions which are dimensionally reduced over coset spaces. We employ the coset space dimensional reduction scheme, which permits the detailed study of the resulting four-dimensional gauge theories. In the context of this scheme we present the difficulties and the suggested ways out in the attempts to describe the observed interactions in a realistic way. (orig.).
Coset space dimensional reduction of gauge theories
International Nuclear Information System (INIS)
Kapetanakis, D.; Zoupanos, G.
1992-01-01
We review the attempts to construct unified theories defined in higher dimensions which are dimensionally reduced over coset spaces. We employ the coset space dimensional reduction scheme, which permits the detailed study of the resulting four-dimensional gauge theories. In the context of this scheme we present the difficulties and the suggested ways out in the attempts to describe the observed interactions in a realistic way. (orig.)
Quadratic divergences and dimensional regularisation
International Nuclear Information System (INIS)
Jack, I.; Jones, D.R.T.
1990-01-01
We present a detailed analysis of quadratic and quartic divergences in dimensionally regulated renormalisable theories. We perform explicit three-loop calculations for a general theory of scalars and fermions. We find that the higher-order quartic divergences are related to the lower-order ones by the renormalisation group β-functions. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Flynn, Charles Joseph [QM Power, Inc., Kansas City, MO (United States)
2018-02-13
failure prone capacitors from the power stage. Q-Sync’s simpler electronics also result in higher efficiency because it eliminates the power required by the PCB to perform the obviated power conversions and PWM processes after line synchronous operating speed is reached in the first 5 seconds of operation, after which the PWM circuits drop out and a much less energy intensive “pass through” circuit takes over, allowing the grid-supplied AC power to sustain the motor’s ongoing operation.
On dimensional reduction over coset spaces
International Nuclear Information System (INIS)
Kapetanakis, D.; Zoupanos, G.
1990-01-01
Gauge theories defined in higher dimensions can be dimensionally reduced over coset spaces giving definite predictions for the resulting four-dimensional theory. We present the most interesting features of these theories as well as an attempt to construct a model with realistic low energy behaviour within this framework. (author)
International Nuclear Information System (INIS)
Gracey, John A.
2006-01-01
We compute the anomalous dimension of the third and fourth moments of the flavour non-singlet twist-2 Wilson and transversity operators at three loops in both the M-bar S-bar and RI' schemes. To assist with the extraction of estimates of matrix elements computed using lattice regularization, the finite parts of the Green's function where the operator is inserted in a quark 2-point function are also provided at three loops in both schemes
Functional Determinants for Radially Separable Partial Differential Operators
Directory of Open Access Journals (Sweden)
G. V. Dunne
2007-01-01
Full Text Available Functional determinants of differential operators play a prominent role in many fields of theoretical and mathematical physics, ranging from condensed matter physics, to atomic, molecular and particle physics. They are, however, difficult to compute reliably in non-trivial cases. In one dimensional problems (i.e. functional determinants of ordinary differential operators, a classic result of Gel’fand and Yaglom greatly simplifies the computation of functional determinants. Here I report some recent progress in extending this approach to higher dimensions (i.e., functional determinants of partial differential operators, with applications in quantum field theory.
Higher order harmonics of reactor neutron equation
International Nuclear Information System (INIS)
Li Fu; Hu Yongming; Luo Zhengpei
1996-01-01
The flux mapping method using the higher order harmonics of the neutron equation is proposed. Based on the bi-orthogonality of the higher order harmonics, the process and formulas for higher order harmonics calculation are derived via the source iteration method with source correction. For the first time, not only any order harmonics for up-to-3-dimensional geometry are achieved, but also the preliminary verification to the capability for flux mapping have been carried out
Computation of focal values and stability analysis of 4-dimensional systems
Directory of Open Access Journals (Sweden)
Bo Sang
2015-08-01
Full Text Available This article presents a recursive formula for computing the n-th singular point values of a class of 4-dimensional autonomous systems, and establishes the algebraic equivalence between focal values and singular point values. The formula is linear and then avoids complicated integrating operations, therefore the calculation can be carried out by computer algebra system such as Maple. As an application of the formula, bifurcation analysis is made for a quadratic system with a Hopf equilibrium, which can have three small limit cycles around an equilibrium point. The theory and methodology developed in this paper can be used for higher-dimensional systems.
Cavalier perspective plots of two-dimensional matrices. Program Stereo
International Nuclear Information System (INIS)
Los Arcos Merino, J.M.
1978-01-01
The program Stereo allows representation of a two-dimensional matrix containing numerical data, in the form of a cavalier perspective, isometric or not, with an angle variable between 0 deg and 180 deg. The representation is in histogram form for each matrix row and those curves which fall behind higher curves and therefore would not be seen are suppressed. It has been written in Fortran V for a Calcomp-936 digital plotter operating off-line with a Univac 1106 computer. Drawing method, subroutine structure and running instructions are described in this paper. (author)
Classification of the Weyl tensor in higher dimensions and applications
International Nuclear Information System (INIS)
Coley, A
2008-01-01
We review the theory of alignment in Lorentzian geometry and apply it to the algebraic classification of the Weyl tensor in higher dimensions. This classification reduces to the well-known Petrov classification of the Weyl tensor in four dimensions. We discuss the algebraic classification of a number of known higher dimensional spacetimes. There are many applications of the Weyl classification scheme, especially when used in conjunction with the higher dimensional frame formalism that has been developed in order to generalize the four-dimensional Newman-Penrose formalism. For example, we discuss higher dimensional generalizations of the Goldberg-Sachs theorem and the peeling theorem. We also discuss the higher dimensional Lorentzian spacetimes with vanishing scalar curvature invariants and constant scalar curvature invariants, which are of interest since they are solutions of supergravity theory. (topical review)
three dimensional photoelastic investigations on thick rectangular
African Journals Online (AJOL)
user
1983-09-01
Sep 1, 1983 ... Thick rectangular plates are investigated by means of three-dimensional photoelasticity ... a thin plate theory and a higher order thick plate theory. 1. ..... number of fringes lest the accuracy of the results will be considerably.
Coupling Navier-stokes and Cahn-hilliard Equations in a Two-dimensional Annular flow Configuration
Vignal, Philippe
2015-06-01
In this work, we present a novel isogeometric analysis discretization for the Navier-Stokes- Cahn-Hilliard equation, which uses divergence-conforming spaces. Basis functions generated with this method can have higher-order continuity, and allow to directly discretize the higher- order operators present in the equation. The discretization is implemented in PetIGA-MF, a high-performance framework for discrete differential forms. We present solutions in a two- dimensional annulus, and model spinodal decomposition under shear flow.
Two-dimensional thermofield bosonization
International Nuclear Information System (INIS)
Amaral, R.L.P.G.; Belvedere, L.V.; Rothe, K.D.
2005-01-01
The main objective of this paper was to obtain an operator realization for the bosonization of fermions in 1 + 1 dimensions, at finite, non-zero temperature T. This is achieved in the framework of the real-time formalism of Thermofield Dynamics. Formally, the results parallel those of the T = 0 case. The well-known two-dimensional Fermion-Boson correspondences at zero temperature are shown to hold also at finite temperature. To emphasize the usefulness of the operator realization for handling a large class of two-dimensional quantum field-theoretic problems, we contrast this global approach with the cumbersome calculation of the fermion-current two-point function in the imaginary-time formalism and real-time formalisms. The calculations also illustrate the very different ways in which the transmutation from Fermi-Dirac to Bose-Einstein statistics is realized
Dimensionality of the human electroencephalogram
Energy Technology Data Exchange (ETDEWEB)
Mayer-Kress, G.; Layne, S.P.
1986-01-01
The goal was to evaluate anesthetic depth in patients by dimensional analysis. Although it was difficult to obtain clean EEG records from the operating room due to noise of electrocautery and movement of the patient's head by operating room personnel. The results are presented on one case of our calculations, followed by a discussion of problems associated with dimensional analysis of the EEG. We consider only two states: aware but quiet, and medium anesthesia. The EEG data we use comes from Hanley and Walts. It was selected because anesthesia was induced by a single agent, and because of its uninterrupted length and lack of artifacts. 26 refs., 27 figs., 1 tab.
Some spacetimes with higher rank Killing-Staeckel tensors
International Nuclear Information System (INIS)
Gibbons, G.W.; Houri, T.; Kubiznak, D.; Warnick, C.M.
2011-01-01
By applying the lightlike Eisenhart lift to several known examples of low-dimensional integrable systems admitting integrals of motion of higher-order in momenta, we obtain four- and higher-dimensional Lorentzian spacetimes with irreducible higher-rank Killing tensors. Such metrics, we believe, are first examples of spacetimes admitting higher-rank Killing tensors. Included in our examples is a four-dimensional supersymmetric pp-wave spacetime, whose geodesic flow is superintegrable. The Killing tensors satisfy a non-trivial Poisson-Schouten-Nijenhuis algebra. We discuss the extension to the quantum regime.
Nonlocal higher order evolution equations
Rossi, Julio D.; Schö nlieb, Carola-Bibiane
2010-01-01
In this article, we study the asymptotic behaviour of solutions to the nonlocal operator ut(x, t)1/4(-1)n-1 (J*Id -1)n (u(x, t)), x ∈ ℝN, which is the nonlocal analogous to the higher order local evolution equation vt(-1)n-1(Δ)nv. We prove
The Opening of Higher Education
Matkin, Gary W.
2012-01-01
In a 1974 report presented to the Organisation for Economic Co-operation and Development (OECD), Martin Trow laid out a framework for understanding large-scale, worldwide changes in higher education. Trow's essay also pointed to the problems that "arise out of the transition from one phase to another in a broad pattern of development of higher…
Compton Operator in Quantum Electrodynamics
International Nuclear Information System (INIS)
Garcia, Hector Luna; Garcia, Luz Maria
2015-01-01
In the frame in the quantum electrodynamics exist four basic operators; the electron self-energy, vacuum polarization, vertex correction, and the Compton operator. The first three operators are very important by its relation with renormalized and Ward identity. However, the Compton operator has equal importance, but without divergence, and little attention has been given it. We have calculated the Compton operator and obtained the closed expression for it in the frame of dimensionally continuous integration and hypergeometric functions
Riccion from higher-dimensional space-time with D-dimensional ...
Indian Academy of Sciences (India)
suggest that space-time above 3 05¢1016 GeV should be fractal. .... Here VD is the volume of SD, g´4·Dµ is the determinant of the metric tensor gMN (M ...... means that above 3.05x1016 GeV, SD is not a smooth surface whereas M4 is smooth.
Karakochuk, Crystal; van den Briel, Tina; Stephens, Derek; Zlotkin, Stanley
2012-10-01
Moderate and severe acute malnutrition affects 13% of children malnutrition affects fewer children but is associated with higher rates of mortality and morbidity. Supplementary feeding programs aim to treat moderate acute malnutrition and prevent the deterioration to severe acute malnutrition. The aim was to compare recovery rates of children with moderate acute malnutrition in supplementary feeding programs by using the newly recommended ration of ready-to-use supplementary food (RUSF) and the more conventional ration of corn-soya blend (CSB) in Ethiopia. A total of 1125 children aged 6-60 mo with moderate acute malnutrition received 16 wk of CSB or RUSF. Children were randomly assigned to receive one or the other food. The daily rations were purposely based on the conventional treatment rations distributed at the time of the study in Ethiopia: 300 g CSB and 32 g vegetable oil in the control group (1413 kcal) and 92 g RUSF in the intervention group (500 kcal). The higher ration size of CSB was provided because of expected food sharing. The HR for children in the CSB group was 0.85 (95% CI: 0.73, 0.99), which indicated that they had 15% lower recovery (P = 0.039). Recovery rates of children at the end of the 16-wk treatment period trended higher in the RUSF group (73%) than in the CSB group (67%) (P = 0.056). In comparison with CSB, the treatment of moderate acute malnutrition with RUSF resulted in higher recovery rates in children, despite the large ration size and higher energy content of the conventional CSB ration.
Liu, Jing; Seo, Jung Hwan; Li, Yubo; Chen, Di; Kurabayashi, Katsuo; Fan, Xudong
2013-03-07
We developed a novel smart multi-channel two-dimensional (2-D) micro-gas chromatography (μGC) architecture that shows promise to significantly improve 2-D μGC performance. In the smart μGC design, a non-destructive on-column gas detector and a flow routing system are installed between the first dimensional separation column and multiple second dimensional separation columns. The effluent from the first dimensional column is monitored in real-time and decision is then made to route the effluent to one of the second dimensional columns for further separation. As compared to the conventional 2-D μGC, the greatest benefit of the smart multi-channel 2-D μGC architecture is the enhanced separation capability of the second dimensional column and hence the overall 2-D GC performance. All the second dimensional columns are independent of each other, and their coating, length, flow rate and temperature can be customized for best separation results. In particular, there is no more constraint on the upper limit of the second dimensional column length and separation time in our architecture. Such flexibility is critical when long second dimensional separation is needed for optimal gas analysis. In addition, the smart μGC is advantageous in terms of elimination of the power intensive thermal modulator, higher peak amplitude enhancement, simplified 2-D chromatogram re-construction and potential scalability to higher dimensional separation. In this paper, we first constructed a complete smart 1 × 2 channel 2-D μGC system, along with an algorithm for automated control/operation of the system. We then characterized and optimized this μGC system, and finally employed it in two important applications that highlight its uniqueness and advantages, i.e., analysis of 31 workplace hazardous volatile organic compounds, and rapid detection and identification of target gas analytes from interference background.
Auluck, S. K. H.
2016-12-01
Recent work on the revised Gratton-Vargas model (Auluck, Phys. Plasmas 20, 112501 (2013); 22, 112509 (2015) and references therein) has demonstrated that there are some aspects of Dense Plasma Focus (DPF), which are not sensitive to details of plasma dynamics and are well captured in an oversimplified model assumption, which contains very little plasma physics. A hyperbolic conservation law formulation of DPF physics reveals the existence of a velocity threshold related to specific energy of dissociation and ionization, above which, the work done during shock propagation is adequate to ensure dissociation and ionization of the gas being ingested. These developments are utilized to formulate an algorithmic definition of DPF optimization that is valid in a wide range of applications, not limited to neutron emission. This involves determination of a set of DPF parameters, without performing iterative model calculations, that lead to transfer of all the energy from the capacitor bank to the plasma at the time of current derivative singularity and conversion of a preset fraction of this energy into magnetic energy, while ensuring that electromagnetic work done during propagation of the plasma remains adequate for dissociation and ionization of neutral gas being ingested. Such a universal optimization criterion is expected to facilitate progress in new areas of DPF research that include production of short lived radioisotopes of possible use in medical diagnostics, generation of fusion energy from aneutronic fuels, and applications in nanotechnology, radiation biology, and materials science. These phenomena are expected to be optimized for fill gases of different kinds and in different ranges of mass density compared to the devices constructed for neutron production using empirical thumb rules. A universal scaling theory of DPF design optimization is proposed and illustrated for designing devices working at one or two orders higher pressure of deuterium than the current
Dirac operators on coset spaces
International Nuclear Information System (INIS)
Balachandran, A.P.; Immirzi, Giorgio; Lee, Joohan; Presnajder, Peter
2003-01-01
The Dirac operator for a manifold Q, and its chirality operator when Q is even dimensional, have a central role in noncommutative geometry. We systematically develop the theory of this operator when Q=G/H, where G and H are compact connected Lie groups and G is simple. An elementary discussion of the differential geometric and bundle theoretic aspects of G/H, including its projective modules and complex, Kaehler and Riemannian structures, is presented for this purpose. An attractive feature of our approach is that it transparently shows obstructions to spin- and spin c -structures. When a manifold is spin c and not spin, U(1) gauge fields have to be introduced in a particular way to define spinors, as shown by Avis, Isham, Cahen, and Gutt. Likewise, for manifolds like SU(3)/SO(3), which are not even spin c , we show that SU(2) and higher rank gauge fields have to be introduced to define spinors. This result has potential consequences for string theories if such manifolds occur as D-branes. The spectra and eigenstates of the Dirac operator on spheres S n =SO(n+1)/SO(n), invariant under SO(n+1), are explicitly found. Aspects of our work overlap with the earlier research of Cahen et al
International Nuclear Information System (INIS)
Berezin, F.A.
1977-01-01
The Laplace-Cazimir operators on the Lie supergroups are defined, and their radial parts are calculated under some general assumptions on supergroup. Under the same assumptions the characters of nondegenerate irreducible finite-dimensional representations are found
Higher class groups of Eichler orders
International Nuclear Information System (INIS)
Guo Xuejun; Kuku, Aderemi
2003-11-01
In this paper, we prove that if A is a quaternion algebra and Λ an Eichler order in A, then the only p-torsion possible in even dimensional higher class groups Cl 2n (Λ) (n ≥ 1) are for those rational primes p which lie under prime ideals of O F at which Λ are not maximal. (author)
Reed, Donovan S; Apsey, Douglas; Steigleman, Walter; Townley, James; Caldwell, Matthew
2017-11-01
In an attempt to maximize treatment outcomes, refractive surgery techniques are being directed toward customized ablations to correct not only lower-order aberrations but also higher-order aberrations specific to the individual eye. Measurement of the entirety of ocular aberrations is the most definitive means to establish the true effect of refractive surgery on image quality and visual performance. Whether or not there is a statistically significant difference in induced higher-order corneal aberrations between the VISX Star S4 (Abbott Medical Optics, Santa Ana, California) and the WaveLight EX500 (Alcon, Fort Worth, Texas) lasers was examined. A retrospective analysis was performed to investigate the difference in root-mean-square (RMS) value of the higher-order corneal aberrations postoperatively between two currently available laser platforms, the VISX Star S4 and the WaveLight EX500 lasers. The RMS is a compilation of higher-order corneal aberrations. Data from 240 total eyes of active duty military or Department of Defense beneficiaries who completed photorefractive keratectomy (PRK) or laser in situ keratomileusis (LASIK) refractive surgery at the Wilford Hall Ambulatory Surgical Center Joint Warfighter Refractive Surgery Center were examined. Using SPSS statistics software (IBM Corp., Armonk, New York), the mean changes in RMS values between the two lasers and refractive surgery procedures were determined. A Student t test was performed to compare the RMS of the higher-order aberrations of the subjects' corneas from the lasers being studied. A regression analysis was performed to adjust for preoperative spherical equivalent. The study and a waiver of informed consent have been approved by the Clinical Research Division of the 59th Medical Wing Institutional Review Board (Protocol Number: 20150093H). The mean change in RMS value for PRK using the VISX laser was 0.00122, with a standard deviation of 0.02583. The mean change in RMS value for PRK using the
Wave equations in higher dimensions
Dong, Shi-Hai
2011-01-01
Higher dimensional theories have attracted much attention because they make it possible to reduce much of physics in a concise, elegant fashion that unifies the two great theories of the 20th century: Quantum Theory and Relativity. This book provides an elementary description of quantum wave equations in higher dimensions at an advanced level so as to put all current mathematical and physical concepts and techniques at the reader’s disposal. A comprehensive description of quantum wave equations in higher dimensions and their broad range of applications in quantum mechanics is provided, which complements the traditional coverage found in the existing quantum mechanics textbooks and gives scientists a fresh outlook on quantum systems in all branches of physics. In Parts I and II the basic properties of the SO(n) group are reviewed and basic theories and techniques related to wave equations in higher dimensions are introduced. Parts III and IV cover important quantum systems in the framework of non-relativisti...
International Nuclear Information System (INIS)
Anon.
1991-01-01
This chapter addresses the extension of previous work in one-dimensional (linear) error theory to two-dimensional error analysis. The topics of the chapter include the definition of two-dimensional error, the probability ellipse, the probability circle, elliptical (circular) error evaluation, the application to position accuracy, and the use of control systems (points) in measurements
Invariant differential operators
Dobrev, Vladimir K
2016-01-01
With applications in quantum field theory, elementary particle physics and general relativity, this two-volume work studies invariance of differential operators under Lie algebras, quantum groups, superalgebras including infinite-dimensional cases, Schrödinger algebras, applications to holography. This first volume covers the general aspects of Lie algebras and group theory.
Invariant differential operators
Dobrev, Vladimir K
With applications in quantum field theory, elementary particle physics and general relativity, this two-volume work studies invariance of differential operators under Lie algebras, quantum groups, superalgebras including infinite-dimensional cases, Schrödinger algebras, applications to holography. This first volume covers the general aspects of Lie algebras and group theory.
International Nuclear Information System (INIS)
Martinez, D; Flores-Urbina, J C; Mota, R D; Granados, V D
2010-01-01
We apply the Schroedinger factorization to construct the ladder operators for the hydrogen atom, Mie-type potential, harmonic oscillator and pseudo-harmonic oscillator in arbitrary dimensions. By generalizing these operators we show that the dynamical algebra for these problems is the su(1, 1) Lie algebra.
Dimensional cosmological principles
International Nuclear Information System (INIS)
Chi, L.K.
1985-01-01
The dimensional cosmological principles proposed by Wesson require that the density, pressure, and mass of cosmological models be functions of the dimensionless variables which are themselves combinations of the gravitational constant, the speed of light, and the spacetime coordinates. The space coordinate is not the comoving coordinate. In this paper, the dimensional cosmological principle and the dimensional perfect cosmological principle are reformulated by using the comoving coordinate. The dimensional perfect cosmological principle is further modified to allow the possibility that mass creation may occur. Self-similar spacetimes are found to be models obeying the new dimensional cosmological principle
Higher spin entanglement entropy at finite temperature with chemical potential
Energy Technology Data Exchange (ETDEWEB)
Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University,5 Yiheyuan Rd, Beijing 100871 (China); Beijing Center for Mathematics and Information Interdisciplinary Sciences, Beijing 100048 (China); Wu, Jie-qiang [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beijing 100871 (China)
2016-07-11
It is generally believed that the semiclassical AdS{sub 3} higher spin gravity could be described by a two dimensional conformal field theory with W-algebra symmetry in the large central charge limit. In this paper, we study the single interval entanglement entropy on the torus in the CFT with a W{sub 3} deformation. More generally we develop the monodromy analysis to compute the two-point function of the light operators under a thermal density matrix with a W{sub 3} chemical potential to the leading order. Holographically we compute the probe action of the Wilson line in the background of the spin-3 black hole with a chemical potential. We find exact agreement.
Spectral computations for bounded operators
Ahues, Mario; Limaye, Balmohan
2001-01-01
Exact eigenvalues, eigenvectors, and principal vectors of operators with infinite dimensional ranges can rarely be found. Therefore, one must approximate such operators by finite rank operators, then solve the original eigenvalue problem approximately. Serving as both an outstanding text for graduate students and as a source of current results for research scientists, Spectral Computations for Bounded Operators addresses the issue of solving eigenvalue problems for operators on infinite dimensional spaces. From a review of classical spectral theory through concrete approximation techniques to finite dimensional situations that can be implemented on a computer, this volume illustrates the marriage of pure and applied mathematics. It contains a variety of recent developments, including a new type of approximation that encompasses a variety of approximation methods but is simple to verify in practice. It also suggests a new stopping criterion for the QR Method and outlines advances in both the iterative refineme...
Nonlinearity management in higher dimensions
International Nuclear Information System (INIS)
Kevrekidis, P G; Pelinovsky, D E; Stefanov, A
2006-01-01
In the present paper, we revisit nonlinearity management of the time-periodic nonlinear Schroedinger equation and the related averaging procedure. By means of rigorous estimates, we show that the averaged nonlinear Schroedinger equation does not blow up in the higher dimensional case so long as the corresponding solution remains smooth. In particular, we show that the H 1 norm remains bounded, in contrast with the usual blow-up mechanism for the focusing Schroedinger equation. This conclusion agrees with earlier works in the case of strong nonlinearity management but contradicts those in the case of weak nonlinearity management. The apparent discrepancy is explained by the divergence of the averaging procedure in the limit of weak nonlinearity management
Bianchi identities in higher dimensions
International Nuclear Information System (INIS)
Pravda, V; Pravdova, A; Coley, A; Milson, R
2004-01-01
A higher dimensional frame formalism is developed in order to study implications of the Bianchi identities for the Weyl tensor in vacuum spacetimes of the algebraic types III and N in arbitrary dimension n. It follows that the principal null congruence is geodesic and expands isotropically in two dimensions and does not expand in n - 4 spacelike dimensions or does not expand at all. It is shown that the existence of such principal geodesic null congruence in vacuum (together with an additional condition on twist) implies an algebraically special spacetime. We also use the Myers-Perry metric as an explicit example of a vacuum type D spacetime to show that principal geodesic null congruences in vacuum type D spacetimes do not share this property
Nonlocal Operational Calculi for Dunkl Operators
Directory of Open Access Journals (Sweden)
Ivan H. Dimovski
2009-03-01
Full Text Available The one-dimensional Dunkl operator $D_k$ with a non-negative parameter $k$, is considered under an arbitrary nonlocal boundary value condition. The right inverse operator of $D_k$, satisfying this condition is studied. An operational calculus of Mikusinski type is developed. In the frames of this operational calculi an extension of the Heaviside algorithm for solution of nonlocal Cauchy boundary value problems for Dunkl functional-differential equations $P(D_ku = f$ with a given polynomial $P$ is proposed. The solution of these equations in mean-periodic functions reduces to such problems. Necessary and sufficient condition for existence of unique solution in mean-periodic functions is found.
Globalisation and Higher Education
Marginson, Simon; van der Wende, Marijk
2007-01-01
Economic and cultural globalisation has ushered in a new era in higher education. Higher education was always more internationally open than most sectors because of its immersion in knowledge, which never showed much respect for juridical boundaries. In global knowledge economies, higher education
Multi-Dimensional Aggregation for Temporal Data
DEFF Research Database (Denmark)
Böhlen, M. H.; Gamper, J.; Jensen, Christian Søndergaard
2006-01-01
Business Intelligence solutions, encompassing technologies such as multi-dimensional data modeling and aggregate query processing, are being applied increasingly to non-traditional data. This paper extends multi-dimensional aggregation to apply to data with associated interval values that capture...... that the data holds for each point in the interval, as well as the case where the data holds only for the entire interval, but must be adjusted to apply to sub-intervals. The paper reports on an implementation of the new operator and on an empirical study that indicates that the operator scales to large data...
Degenerate conformal theories on higher-genus surfaces
International Nuclear Information System (INIS)
Gerasimov, A.A.
1989-01-01
Two-dimensional degenerate field theories on higher-genus surfaces are investigated. Objects are built on the space of moduli, whose linear combinations are hypothetically conformal blocks in degenerate theories
Tokas, Theodoros; Gözen, Ali Serdar; Avgeris, Margaritis; Tschada, Alexandra; Fiedler, Marcel; Klein, Jan; Rassweiler, Jens
2017-10-01
Posture, vision, and instrumentation limitations are the main predicaments of conventional laparoscopy. To combine the ETHOS surgical chair, the three-dimensional laparoscope, and the Radius Surgical System manipulators, and compare the system with conventional laparoscopy and da Vinci in terms of task completion times and discomfort. Fifteen trainees performed the three main laparoscopic suturing tasks of the Heilbronn training program (IV: simulation of dorsal venous complex suturing; V: circular suturing of tubular structure; and VI: urethrovesical anastomosis) in a pelvi trainer. The tasks were performed conventionally, utilizing the three devices, and robotically. Task completion times were recorded and the surgeon discomfort was evaluated using questionnaires. Task completion times were compared using nonparametric Wilcoxon signed rank test and ergonomic scores were compared using Pearson chi-square test. The use of the full laparoscopic set (ETHOS chair, three-dimensional laparoscopic camera, Radius Surgical System needle holders), resulted in a significant improvement of the completion time of the three tested tasks compared with conventional laparoscopy (psystem nullified heavy discomfort for Tasks IV and V and minimized it (6.7%) for the most demanding Task VI. Especially for Task VI, all trainees gained benefit, by using the system, in terms of task completion times and discomfort. The limited trainee robotic experience and the questionnaire subjectivity could be a potential limitation. The ergonomic laparoscopic system offers significantly improved task completion times and ergonomy than conventional laparoscopy. Furthermore, it demonstrates comparable results to robotic surgery. The study was conducted in a pelvi trainer and no patients were recruited. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.
The search for higher symmetry in string theory
Energy Technology Data Exchange (ETDEWEB)
Witten, E [Institute for Advanced Study, Princeton, NJ (USA)
1989-11-17
Some remarks are made about the nature and role of the search for higher symmetry in string theory. These symmetries are most likely to be uncovered in a mysterious 'unbroken phase', for which (2+1)-dimensional gravity provides an interesting and soluble model. New insights about conformal field theory, in which one gets 'out of flatland' to see a wider symmetry from a higher-dimensional vantage point, may offer clues to the unbroken phase of string theory. (author).
Spherical dust collapse in higher dimensions
International Nuclear Information System (INIS)
Goswami, Rituparno; Joshi, Pankaj S.
2004-01-01
We consider here whether it is possible to recover cosmic censorship when a transition is made to higher-dimensional spacetimes, by studying the spherically symmetric dust collapse in an arbitrary higher spacetime dimension. It is pointed out that if only black holes are to result as the end state of a continual gravitational collapse, several conditions must be imposed on the collapsing configuration, some of which may appear to be restrictive, and we need to study carefully if these can be suitably motivated physically in a realistic collapse scenario. It would appear, that, in a generic higher-dimensional dust collapse, both black holes and naked singularities would develop as end states as indicated by the results here. The mathematical approach developed here generalizes and unifies the earlier available results on higher-dimensional dust collapse as we point out. Further, the dependence of black hole or naked singularity end states as collapse outcomes on the nature of the initial data from which the collapse develops is brought out explicitly and in a transparent manner as we show here. Our method also allows us to consider here in some detail the genericity and stability aspects related to the occurrence of naked singularities in gravitational collapse
On infinite-dimensional state spaces
International Nuclear Information System (INIS)
Fritz, Tobias
2013-01-01
It is well known that the canonical commutation relation [x, p]=i can be realized only on an infinite-dimensional Hilbert space. While any finite set of experimental data can also be explained in terms of a finite-dimensional Hilbert space by approximating the commutation relation, Occam's razor prefers the infinite-dimensional model in which [x, p]=i holds on the nose. This reasoning one will necessarily have to make in any approach which tries to detect the infinite-dimensionality. One drawback of using the canonical commutation relation for this purpose is that it has unclear operational meaning. Here, we identify an operationally well-defined context from which an analogous conclusion can be drawn: if two unitary transformations U, V on a quantum system satisfy the relation V −1 U 2 V=U 3 , then finite-dimensionality entails the relation UV −1 UV=V −1 UVU; this implication strongly fails in some infinite-dimensional realizations. This is a result from combinatorial group theory for which we give a new proof. This proof adapts to the consideration of cases where the assumed relation V −1 U 2 V=U 3 holds only up to ε and then yields a lower bound on the dimension.
On infinite-dimensional state spaces
Fritz, Tobias
2013-05-01
It is well known that the canonical commutation relation [x, p] = i can be realized only on an infinite-dimensional Hilbert space. While any finite set of experimental data can also be explained in terms of a finite-dimensional Hilbert space by approximating the commutation relation, Occam's razor prefers the infinite-dimensional model in which [x, p] = i holds on the nose. This reasoning one will necessarily have to make in any approach which tries to detect the infinite-dimensionality. One drawback of using the canonical commutation relation for this purpose is that it has unclear operational meaning. Here, we identify an operationally well-defined context from which an analogous conclusion can be drawn: if two unitary transformations U, V on a quantum system satisfy the relation V-1U2V = U3, then finite-dimensionality entails the relation UV-1UV = V-1UVU; this implication strongly fails in some infinite-dimensional realizations. This is a result from combinatorial group theory for which we give a new proof. This proof adapts to the consideration of cases where the assumed relation V-1U2V = U3 holds only up to ɛ and then yields a lower bound on the dimension.
Structure of Hilbert space operators
Jiang, Chunlan
2006-01-01
This book exposes the internal structure of non-self-adjoint operators acting on complex separable infinite dimensional Hilbert space, by analyzing and studying the commutant of operators. A unique presentation of the theorem of Cowen-Douglas operators is given. The authors take the strongly irreducible operator as a basic model, and find complete similarity invariants of Cowen-Douglas operators by using K -theory, complex geometry and operator algebra tools. Sample Chapter(s). Chapter 1: Background (153 KB). Contents: Jordan Standard Theorem and K 0 -Group; Approximate Jordan Theorem of Opera
Topological higher gauge theory: From BF to BFCG theory
International Nuclear Information System (INIS)
Girelli, F.; Pfeiffer, H.; Popescu, E. M.
2008-01-01
We study generalizations of three- and four-dimensional BF theories in the context of higher gauge theory. First, we construct topological higher gauge theories as discrete state sum models and explain how they are related to the state sums of Yetter, Mackaay, and Porter. Under certain conditions, we can present their corresponding continuum counterparts in terms of classical Lagrangians. We then explain that two of these models are already familiar from the literature: the ΣΦEA model of three-dimensional gravity coupled to topological matter and also a four-dimensional model of BF theory coupled to topological matter
Observables and microscopic entropy of higher spin black holes
Compère, Geoffrey; Jottar, Juan I.; Song, Wei
2013-11-01
In the context of recently proposed holographic dualities between higher spin theories in AdS3 and (1 + 1)-dimensional CFTs with symmetry algebras, we revisit the definition of higher spin black hole thermodynamics and the dictionary between bulk fields and dual CFT operators. We build a canonical formalism based on three ingredients: a gauge-invariant definition of conserved charges and chemical potentials in the presence of higher spin black holes, a canonical definition of entropy in the bulk, and a bulk-to-boundary dictionary aligned with the asymptotic symmetry algebra. We show that our canonical formalism shares the same formal structure as the so-called holomorphic formalism, but differs in the definition of charges and chemical potentials and in the bulk-to-boundary dictionary. Most importantly, we show that it admits a consistent CFT interpretation. We discuss the spin-2 and spin-3 cases in detail and generalize our construction to theories based on the hs[ λ] algebra, and on the sl( N,[InlineMediaObject not available: see fulltext.]) algebra for any choice of sl(2 ,[InlineMediaObject not available: see fulltext.]) embedding.
Higher Education and Inequality
Brown, Roger
2018-01-01
After climate change, rising economic inequality is the greatest challenge facing the advanced Western societies. Higher education has traditionally been seen as a means to greater equality through its role in promoting social mobility. But with increased marketisation higher education now not only reflects the forces making for greater inequality…
Higher Education in California
Public Policy Institute of California, 2016
2016-01-01
Higher education enhances Californians' lives and contributes to the state's economic growth. But population and education trends suggest that California is facing a large shortfall of college graduates. Addressing this shortfall will require strong gains for groups that have been historically underrepresented in higher education. Substantial…
Reimagining Christian Higher Education
Hulme, E. Eileen; Groom, David E., Jr.; Heltzel, Joseph M.
2016-01-01
The challenges facing higher education continue to mount. The shifting of the U.S. ethnic and racial demographics, the proliferation of advanced digital technologies and data, and the move from traditional degrees to continuous learning platforms have created an unstable environment to which Christian higher education must adapt in order to remain…
Elwick, Alex; Cannizzaro, Sara
2017-01-01
This paper investigates the higher education literature surrounding happiness and related notions: satisfaction, despair, flourishing and well-being. It finds that there is a real dearth of literature relating to profound happiness in higher education: much of the literature using the terms happiness and satisfaction interchangeably as if one were…
Bank, Barbara J., Ed.
2011-01-01
This comprehensive, encyclopedic review explores gender and its impact on American higher education across historical and cultural contexts. Challenging recent claims that gender inequities in U.S. higher education no longer exist, the contributors--leading experts in the field--reveal the many ways in which gender is embedded in the educational…
DEFF Research Database (Denmark)
Zou, Yihuan
is about constructing a more inclusive understanding of quality in higher education through combining the macro, meso and micro levels, i.e. from the perspectives of national policy, higher education institutions as organizations in society, individual teaching staff and students. It covers both......Quality in higher education was not invented in recent decades – universities have always possessed mechanisms for assuring the quality of their work. The rising concern over quality is closely related to the changes in higher education and its social context. Among others, the most conspicuous...... changes are the massive expansion, diversification and increased cost in higher education, and new mechanisms of accountability initiated by the state. With these changes the traditional internally enacted academic quality-keeping has been given an important external dimension – quality assurance, which...
Noncommutative operational calculus
Directory of Open Access Journals (Sweden)
Henry E. Heatherly
1999-12-01
Full Text Available Oliver Heaviside's operational calculus was placed on a rigorous mathematical basis by Jan Mikusinski, who constructed an algebraic setting for the operational methods. In this paper, we generalize Mikusi'{n}ski's methods to solve linear ordinary differential equations in which the unknown is a matrix- or linear operator-valued function. Because these functions can be zero-divisors and do not necessarily commute, Mikusi'{n}ski's one-dimensional calculus cannot be used. The noncommuative operational calculus developed here,however, is used to solve a wide class of such equations. In addition, we provide new proofs of existence and uniqueness theorems for certain matrix- and operator valued Volterra integral and integro-differential equations. Several examples are given which demonstrate these new methods.
Equilibrium: three-dimensional configurations
International Nuclear Information System (INIS)
Anon.
1987-01-01
This chapter considers toroidal MHD configurations that are inherently three-dimensional. The motivation for investigation such complicated equilibria is that they possess the potential for providing toroidal confinement without the need of a net toroidal current. This leads to a number of advantages with respect to fusion power generation. First, the attractive feature of steady-state operation becomes more feasible since such configurations no longer require a toroidal current transformer. Second, with zero net current, one potentially dangerous class of MHD instabilities, the current-driven kink modes, is eliminated. Finally, three-dimensional configurations possess nondegenerate flux surfaces even in the absence of plasma pressure and plasma current. Although there is an enormous range of possible three-dimensional equilibria, the configurations of interest are accurately described as axisymmetric tori with superimposed helical fields; furthermore, they possess no net toroidal current. Instead, two different and less obvious restoring forces are developed: the helical sideband force and the toroidal dipole current force. Each is discussed in detail in Chapter 7. A detailed discussion of the parallel current constraint, including its physical significance, is given in section 7.2. A general analysis of helical sideband equilibria, along with a detailed description of the Elmo bumpy torus, is presented in sections 7.3 and 7.4. A general description of toroidal dipole-current equilibria, including a detailed discussion of stellarators, heliotrons, and torsatrons, is given in sections 7.5 and 7.6
International Nuclear Information System (INIS)
Brown, J.D.
1988-01-01
This book addresses the subject of gravity theories in two and three spacetime dimensions. The prevailing philosophy is that lower dimensional models of gravity provide a useful arena for developing new ideas and insights, which are applicable to four dimensional gravity. The first chapter consists of a comprehensive introduction to both two and three dimensional gravity, including a discussion of their basic structures. In the second chapter, the asymptotic structure of three dimensional Einstein gravity with a negative cosmological constant is analyzed. The third chapter contains a treatment of the effects of matter sources in classical two dimensional gravity. The fourth chapter gives a complete analysis of particle pair creation by electric and gravitational fields in two dimensions, and the resulting effect on the cosmological constant
Three dimensional strained semiconductors
Voss, Lars; Conway, Adam; Nikolic, Rebecca J.; Leao, Cedric Rocha; Shao, Qinghui
2016-11-08
In one embodiment, an apparatus includes a three dimensional structure comprising a semiconductor material, and at least one thin film in contact with at least one exterior surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the three dimensional structure. In another embodiment, a method includes forming a three dimensional structure comprising a semiconductor material, and depositing at least one thin film on at least one surface of the three dimensional structure for inducing a strain in the structure, the thin film being characterized as providing at least one of: an induced strain of at least 0.05%, and an induced strain in at least 5% of a volume of the structure.
Clustering high dimensional data
DEFF Research Database (Denmark)
Assent, Ira
2012-01-01
High-dimensional data, i.e., data described by a large number of attributes, pose specific challenges to clustering. The so-called ‘curse of dimensionality’, coined originally to describe the general increase in complexity of various computational problems as dimensionality increases, is known...... to render traditional clustering algorithms ineffective. The curse of dimensionality, among other effects, means that with increasing number of dimensions, a loss of meaningful differentiation between similar and dissimilar objects is observed. As high-dimensional objects appear almost alike, new approaches...... for clustering are required. Consequently, recent research has focused on developing techniques and clustering algorithms specifically for high-dimensional data. Still, open research issues remain. Clustering is a data mining task devoted to the automatic grouping of data based on mutual similarity. Each cluster...
Creating marketing strategies for higher education institutions
Lidia Białoń
2015-01-01
The article presents a thesis that the primary premise of creating marketing strategies for higher education institution is a three-dimensional notion of marketing. The first dimension lies in the theoretical notions of the essence of marketing, including the transactional marketing (1.0), relationship marketing (2.0) and spiritual marketing (3.0). The second dimension is formed by methods of marketing research and accurate notions of marketing, while the third are channels of marketing infor...
Glowinski, R.; Dean, E.J.; Guidoboni, G.; Juárez, L.H.; Pan, T.-W.
2008-01-01
The main goal of this article is to review some recent applications of operator-splitting methods. We will show that these methods are well-suited to the numerical solution of outstanding problems from various areas in Mechanics, Physics and Differential Geometry, such as the direct numerical simulation of particulate flow, free boundary problems with surface tension for incompressible viscous fluids, and the elliptic real Monge--Ampère equation. The results of numerical ...
Application of three-dimensional CT reconstruction cranioplasty
International Nuclear Information System (INIS)
Yan Shuli; Yun Yongxing; Wan Kunming; Qiu Jian
2011-01-01
Objective: To study the application of three-dimensional CT reconstruction in cranioplasty. Methods: 46 patients with skull defect were divided into two group. One group underwent CT examination and three-dimensional reconstruction, and then the Titanium nets production company manufactured corresponding titanium meshes were shaped those data before the operation. The other group received traditional operation in which titanium meshes were shaped during operation. The average time of operation were compared. Results: The average time of operation of the first group is 86.6±13.6 mins, and that of the second group is 115±15.0 mins. The difference of average operation time between the two groups was statistically significant. Conclusion: Three-dimensional CT reconstruction techniques contribute to shorten the average operation time, reduce the intensity of neurosurgeon's work and the patien's risk. (authors)
Bridges, Ann; Mitchell, John
2015-01-01
A brand new edition of the former Higher English: Close Reading , completely revised and updated for the new Higher element (Reading for Understanding, Analysis and Evaluation) - worth 30% of marks in the final exam!. We are working with SQA to secure endorsement for this title. Written by two highly experienced authors this book shows you how to practice for the Reading for Understanding, Analysis and Evaluation section of the new Higher English exam. This book introduces the terms and concepts that lie behind success and offers guidance on the interpretation of questions and targeting answer
Finite-dimensional effects and critical indices of one-dimensional quantum models
International Nuclear Information System (INIS)
Bogolyubov, N.M.; Izergin, A.G.; Reshetikhin, N.Yu.
1986-01-01
Critical indices, depending on continuous parameters in Bose-gas quantum models and Heisenberg 1/2 spin antiferromagnetic in two-dimensional space-time at zero temperature, have been calculated by means of finite-dimensional effects. In this case the long-wave asymptotics of the correlation functions is of a power character. Derivation of man asymptotics terms is reduced to the determination of a central charge in the appropriate Virassoro algebra representation and the anomalous dimension-operator spectrum in this representation. The finite-dimensional effects allow to find these values
Multi-dimensional quasitoeplitz Markov chains
Directory of Open Access Journals (Sweden)
Alexander N. Dudin
1999-01-01
Full Text Available This paper deals with multi-dimensional quasitoeplitz Markov chains. We establish a sufficient equilibrium condition and derive a functional matrix equation for the corresponding vector-generating function, whose solution is given algorithmically. The results are demonstrated in the form of examples and applications in queues with BMAP-input, which operate in synchronous random environment.
Planning for Higher Education.
Lindstrom, Caj-Gunnar
1984-01-01
Decision processes for strategic planning for higher education institutions are outlined using these parameters: institutional goals and power structure, organizational climate, leadership attitudes, specific problem type, and problem-solving conditions and alternatives. (MSE)
N.V. Provozin; А.S. Teletov
2011-01-01
The article discusses the features advertising higher education institution. The analysis results of marketing research students for their choice of institutions and further study. Principles of the advertising campaign on three levels: the university, the faculty, the separate department.
High dimensional neurocomputing growth, appraisal and applications
Tripathi, Bipin Kumar
2015-01-01
The book presents a coherent understanding of computational intelligence from the perspective of what is known as "intelligent computing" with high-dimensional parameters. It critically discusses the central issue of high-dimensional neurocomputing, such as quantitative representation of signals, extending the dimensionality of neuron, supervised and unsupervised learning and design of higher order neurons. The strong point of the book is its clarity and ability of the underlying theory to unify our understanding of high-dimensional computing where conventional methods fail. The plenty of application oriented problems are presented for evaluating, monitoring and maintaining the stability of adaptive learning machine. Author has taken care to cover the breadth and depth of the subject, both in the qualitative as well as quantitative way. The book is intended to enlighten the scientific community, ranging from advanced undergraduates to engineers, scientists and seasoned researchers in computational intelligenc...
International Nuclear Information System (INIS)
Accioly, A.J.
1987-01-01
A possible classical route conducting towards a general relativity theory with higher-derivatives starting, in a sense, from first principles, is analysed. A completely causal vacuum solution with the symmetries of the Goedel universe is obtained in the framework of this higher-derivative gravity. This very peculiar and rare result is the first known vcuum solution of the fourth-order gravity theory that is not a solution of the corresponding Einstein's equations.(Author) [pt
CERN. Geneva
2014-01-01
The conjectured relation between higher spin theories on anti de-Sitter (AdS) spaces and weakly coupled conformal field theories is reviewed. I shall then outline the evidence in favour of a concrete duality of this kind, relating a specific higher spin theory on AdS3 to a family of 2d minimal model CFTs. Finally, I shall explain how this relation fits into the framework of the familiar stringy AdS/CFT correspondence.
Wang, Lie; Chen, Zhi-Yuan; Liu, Rong; Zeng, Hao
2017-08-01
To study the value and satisfaction of three-dimensional printing implant template and conventional implant template in multi-tooth dental implantation. Thirty cases (83 teeth) with missing teeth needing to be implanted were randomly divided into conventional implant template group (CIT group, 15 cases, 42 teeth) and 3D printing implant template group (TDPIT group, 15 cases, 41 teeth). Patients in CIT group were operated by using conventional implant template, while patients in TDPIT group were operated by using three-dimensional printing implant template. The differences of implant neck and tip deviation, implant angle deviation and angle satisfaction between the two groups were compared. The difference of probing depth and bone resorption of implant were compared 1 year after operation between the two groups. The difference of success rate and satisfaction of dental implantation were compared 1 year after operation between the two groups. SPSS19.0 software package was used for statistical analysis. The deviation direction of the neck and the tip in disto-mesial, bucco-palatal, vertical direction and angle of implants in disto-mesial and bucco-palatal direction in TDPIT group were significantly lower than in CIT group (P0.05). The difference of the cumulative success rate in dental implantation at 3 months and 6 months between the two groups were not significant (P>0.05), but the cumulative success rate of TDPIT group was significantly higher than CIT group at 9 months and 1 year (90.48% vs 100%,P=0.043). The patients' satisfaction rate of dental implantation in TDPIT group was significantly higher than in CIT group (86.67% vs 53.33%, P=0.046). Using three-dimensional printing implant template can obtain better accuracy of implant, higher implant success rate and better patients' satisfaction than using conventional implant template. It is suitable for clinical application.
Nonlocal higher order evolution equations
Rossi, Julio D.
2010-06-01
In this article, we study the asymptotic behaviour of solutions to the nonlocal operator ut(x, t)1/4(-1)n-1 (J*Id -1)n (u(x, t)), x ∈ ℝN, which is the nonlocal analogous to the higher order local evolution equation vt(-1)n-1(Δ)nv. We prove that the solutions of the nonlocal problem converge to the solution of the higher order problem with the right-hand side given by powers of the Laplacian when the kernel J is rescaled in an appropriate way. Moreover, we prove that solutions to both equations have the same asymptotic decay rate as t goes to infinity. © 2010 Taylor & Francis.
Dimensional comparison theory.
Möller, Jens; Marsh, Herb W
2013-07-01
Although social comparison (Festinger, 1954) and temporal comparison (Albert, 1977) theories are well established, dimensional comparison is a largely neglected yet influential process in self-evaluation. Dimensional comparison entails a single individual comparing his or her ability in a (target) domain with his or her ability in a standard domain (e.g., "How good am I in math compared with English?"). This article reviews empirical findings from introspective, path-analytic, and experimental studies on dimensional comparisons, categorized into 3 groups according to whether they address the "why," "with what," or "with what effect" question. As the corresponding research shows, dimensional comparisons are made in everyday life situations. They impact on domain-specific self-evaluations of abilities in both domains: Dimensional comparisons reduce self-concept in the worse off domain and increase self-concept in the better off domain. The motivational basis for dimensional comparisons, their integration with recent social cognitive approaches, and the interdependence of dimensional, temporal, and social comparisons are discussed. PsycINFO Database Record (c) 2013 APA, all rights reserved.
Redesigning Higher Education: Embracing a New Paradigm
Watson, William R.; Watson, Sunnie Lee
2014-01-01
Higher education is under enormous pressure to transform itself and embrace a new paradigm. Operating under an outdated model that no longer aligns with the realities of modern society, institutions of higher education are recognizing the need to drastically remake themselves or possibly cease to exist. This article explores the current landscape…
Difference equations in massive higher order calculations
International Nuclear Information System (INIS)
Bierenbaum, I.; Bluemlein, J.; Klein, S.; Schneider, C.
2007-07-01
The calculation of massive 2-loop operator matrix elements, required for the higher order Wilson coefficients for heavy flavor production in deeply inelastic scattering, leads to new types of multiple infinite sums over harmonic sums and related functions, which depend on the Mellin parameter N. We report on the solution of these sums through higher order difference equations using the summation package Sigma. (orig.)
Competitive Intelligence: Significance in Higher Education
Barrett, Susan E.
2010-01-01
Historically noncompetitive, the higher education sector is now having to adjust dramatically to new and increasing demands on numerous levels. To remain successfully operational within the higher educational market universities today must consider all relevant forces which can impact present and future planning. Those institutions that were…
Three dimensional canonical transformations
International Nuclear Information System (INIS)
Tegmen, A.
2010-01-01
A generic construction of canonical transformations is given in three-dimensional phase spaces on which Nambu bracket is imposed. First, the canonical transformations are defined as based on cannonade transformations. Second, it is shown that determination of the generating functions and the transformation itself for given generating function is possible by solving correspondent Pfaffian differential equations. Generating functions of type are introduced and all of them are listed. Infinitesimal canonical transformations are also discussed as the complementary subject. Finally, it is shown that decomposition of canonical transformations is also possible in three-dimensional phase spaces as in the usual two-dimensional ones.
Sarathy, Mani
2016-08-17
This chapter focuses on the production and combustion of alcohol fuels with four or more carbon atoms, which we classify as higher alcohols. It assesses the feasibility of utilizing various C4-C8 alcohols as fuels for internal combustion engines. Utilizing higher-molecular-weight alcohols as fuels requires careful analysis of their fuel properties. ASTM standards provide fuel property requirements for spark-ignition (SI) and compression-ignition (CI) engines such as the stability, lubricity, viscosity, and cold filter plugging point (CFPP) properties of blends of higher alcohols. Important combustion properties that are studied include laminar and turbulent flame speeds, flame blowout/extinction limits, ignition delay under various mixing conditions, and gas-phase and particulate emissions. The chapter focuses on the combustion of higher alcohols in reciprocating SI and CI engines and discusses higher alcohol performance in SI and CI engines. Finally, the chapter identifies the sources, production pathways, and technologies currently being pursued for production of some fuels, including n-butanol, iso-butanol, and n-octanol.
Henneaux, Marc; Vasiliev, Mikhail A
2017-01-01
Symmetries play a fundamental role in physics. Non-Abelian gauge symmetries are the symmetries behind theories for massless spin-1 particles, while the reparametrization symmetry is behind Einstein's gravity theory for massless spin-2 particles. In supersymmetric theories these particles can be connected also to massless fermionic particles. Does Nature stop at spin-2 or can there also be massless higher spin theories. In the past strong indications have been given that such theories do not exist. However, in recent times ways to evade those constraints have been found and higher spin gauge theories have been constructed. With the advent of the AdS/CFT duality correspondence even stronger indications have been given that higher spin gauge theories play an important role in fundamental physics. All these issues were discussed at an international workshop in Singapore in November 2015 where the leading scientists in the field participated. This volume presents an up-to-date, detailed overview of the theories i...
INTERNATIONALIZATION IN HIGHER EDUCATION
Directory of Open Access Journals (Sweden)
Catalina Crisan-Mitra
2016-03-01
Full Text Available Internationalization of higher education is one of the key trends of development. There are several approaches on how to achieve competitiveness and performance in higher education and international academic mobility; students’ exchange programs, partnerships are some of the aspects that can play a significant role in this process. This paper wants to point out the student’s perception regarding two main directions: one about the master students’ expectation regarding how an internationalized master should be organized and should function, and second the degree of satisfaction of the beneficiaries of internationalized master programs from Babe-Bolyai University. This article is based on an empirical qualitative research that was implemented to students of an internationalized master from the Faculty of Economics and Business Administration. This research can be considered a useful example for those preoccupied to increase the quality of higher education and conclusions drawn have relevance both theoretically and especially practically.
DEFF Research Database (Denmark)
Zou, Yihuan; Zhao, Yingsheng; Du, Xiangyun
. This transformation involves a broad scale of change at individual level, organizational level, and societal level. In this change process in higher education, staff development remains one of the key elements for university innovation and at the same time demands a systematic and holistic approach.......This paper starts with a critical approach to reflect on the current practice of quality assessment and assurance in higher education. This is followed by a proposal that in response to the global challenges for improving the quality of higher education, universities should take active actions...... of change by improving the quality of teaching and learning. From a constructivist perspective of understanding education and learning, this paper also discusses why and how universities should give more weight to learning and change the traditional role of teaching to an innovative approach of facilitation...
Holography and higher-spin theories
International Nuclear Information System (INIS)
Petkou, T.
2005-01-01
I review recent work on the holographic relation between higher-spin theories in Anti-de Sitter spaces and conformal field theories. I present the main results of studies concerning the higher-spin holographic dual of the three-dimensional O(N) vector model. I discuss the special role played by certain double-trace deformations in Conformal Field Theories that have higher-spin holographic duals. Moreover, I show that duality transformations in a U(1) gauge theory on AdS 4 induce boundary double-trace deformations and argue that a similar effect takes place in the holography of linearized higher-spin theories on AdS 4 . (Abstract Copyright [2005], Wiley Periodicals, Inc.)
[Bone drilling simulation by three-dimensional imaging].
Suto, Y; Furuhata, K; Kojima, T; Kurokawa, T; Kobayashi, M
1989-06-01
The three-dimensional display technique has a wide range of medical applications. Pre-operative planning is one typical application: in orthopedic surgery, three-dimensional image processing has been used very successfully. We have employed this technique in pre-operative planning for orthopedic surgery, and have developed a simulation system for bone-drilling. Positive results were obtained by pre-operative rehearsal; when a region of interest is indicated by means of a mouse on the three-dimensional image displayed on the CRT, the corresponding region appears on the slice image which is displayed simultaneously. Consequently, the status of the bone-drilling is constantly monitored. In developing this system, we have placed emphasis on the quality of the reconstructed three-dimensional images, on fast processing, and on the easy operation of the surgical planning simulation.
Reputation in Higher Education
DEFF Research Database (Denmark)
Martensen, Anne; Grønholdt, Lars
2005-01-01
leaders of higher education institutions to set strategic directions and support their decisions in an effort to create even better study programmes with a better reputation. Finally, managerial implications and directions for future research are discussed.Keywords: Reputation, image, corporate identity......The purpose of this paper is to develop a reputation model for higher education programmes, provide empirical evidence for the model and illustrate its application by using Copenhagen Business School (CBS) as the recurrent case. The developed model is a cause-and-effect model linking image...
Reputation in Higher Education
DEFF Research Database (Denmark)
Plewa, Carolin; Ho, Joanne; Conduit, Jodie
2016-01-01
Reputation is critical for institutions wishing to attract and retain students in today's competitive higher education setting. Drawing on the resource based view and configuration theory, this research proposes that Higher Education Institutions (HEIs) need to understand not only the impact...... of independent resources but of resource configurations when seeking to achieve a strong, positive reputation. Utilizing fuzzy set qualitative comparative analysis (fsQCA), the paper provides insight into different configurations of resources that HEIs can utilize to build their reputation within their domestic...
Navigating in higher education
DEFF Research Database (Denmark)
Thingholm, Hanne Balsby; Reimer, David; Keiding, Tina Bering
Denne rapport er skrevet på baggrund af spørgeskemaundersøgelsen – Navigating in Higher Education (NiHE) – der rummer besvarelser fra 1410 bachelorstuderende og 283 undervisere fordelt på ni uddannelser fra Aarhus Universitet: Uddannelsesvidenskab, Historie, Nordisk sprog og litteratur, Informati......Denne rapport er skrevet på baggrund af spørgeskemaundersøgelsen – Navigating in Higher Education (NiHE) – der rummer besvarelser fra 1410 bachelorstuderende og 283 undervisere fordelt på ni uddannelser fra Aarhus Universitet: Uddannelsesvidenskab, Historie, Nordisk sprog og litteratur...
Zhang, Pei-feng; Hu, Yuan-man; He, Hong-shi
2010-05-01
The demand for accurate and up-to-date spatial information of urban buildings is becoming more and more important for urban planning, environmental protection, and other vocations. Today's commercial high-resolution satellite imagery offers the potential to extract the three-dimensional information of urban buildings. This paper extracted the three-dimensional information of urban buildings from QuickBird imagery, and validated the precision of the extraction based on Barista software. It was shown that the extraction of three-dimensional information of the buildings from high-resolution satellite imagery based on Barista software had the advantages of low professional level demand, powerful universality, simple operation, and high precision. One pixel level of point positioning and height determination accuracy could be achieved if the digital elevation model (DEM) and sensor orientation model had higher precision and the off-Nadir View Angle was relatively perfect.
Conover, Willis M.
1992-01-01
Maintains that the social studies reform movement includes a call for the de-emphasis of rote memory and more attention to the development of higher-order thinking skills. Discusses the "thinking tasks" concept derived from the work of Hilda Taba and asserts that the tasks can be used with almost any social studies topic. (CFR)
DEFF Research Database (Denmark)
Ernst, Erik
2003-01-01
This paper introduces the notion of higher-order inheritance hierarchies. They are useful because they provide well-known benefits of object-orientation at the level of entire hierarchies-benefits which are not available with current approaches. Three facets must be adressed: First, it must be po...
Higher Education Funding Formulas.
McKeown-Moak, Mary P.
1999-01-01
One of the most critical components of the college or university chief financial officer's job is budget planning, especially using formulas. A discussion of funding formulas looks at advantages, disadvantages, and types of formulas used by states in budgeting for higher education, and examines how chief financial officers can position the campus…
Thompson, Dennis F.
1989-01-01
John Stuart Mill's principle of liberty is discussed with the view that it needs to be revised to guide moral judgments in higher education. Three key elements need to be modified: the action that is constrained; the constraint on the action; and the agent whose action is constrained. (MLW)
Sarathy, Mani
2016-01-01
This chapter focuses on the production and combustion of alcohol fuels with four or more carbon atoms, which we classify as higher alcohols. It assesses the feasibility of utilizing various C4-C8 alcohols as fuels for internal combustion engines
Evaluation in Higher Education
Bognar, Branko; Bungic, Maja
2014-01-01
One of the means of transforming classroom experience is by conducting action research with students. This paper reports about the action research with university students. It has been carried out within a semester of the course "Methods of Upbringing". Its goal has been to improve evaluation of higher education teaching. Different forms…
DEFF Research Database (Denmark)
Bandaru, Sunith; Tutum, Cem Celal; Deb, Kalyanmoy
2011-01-01
we introduce the higher-level innovization task through an application of a manufacturing process simulation for the Friction Stir Welding (FSW) process where commonalities among two different Pareto-optimal fronts are analyzed. Multiple design rules are simultaneously deciphered from each front...
Benchmarking for Higher Education.
Jackson, Norman, Ed.; Lund, Helen, Ed.
The chapters in this collection explore the concept of benchmarking as it is being used and developed in higher education (HE). Case studies and reviews show how universities in the United Kingdom are using benchmarking to aid in self-regulation and self-improvement. The chapters are: (1) "Introduction to Benchmarking" (Norman Jackson…
Creativity in Higher Education
Gaspar, Drazena; Mabic, Mirela
2015-01-01
The paper presents results of research related to perception of creativity in higher education made by the authors at the University of Mostar from Bosnia and Herzegovina. This research was based on a survey conducted among teachers and students at the University. The authors developed two types of questionnaires, one for teachers and the other…
California's Future: Higher Education
Johnson, Hans
2015-01-01
California's higher education system is not keeping up with the changing economy. Projections suggest that the state's economy will continue to need more highly educated workers. In 2025, if current trends persist, 41 percent of jobs will require at least a bachelor's degree and 36 percent will require some college education short of a bachelor's…
Cyberbullying in Higher Education
Minor, Maria A.; Smith, Gina S.; Brashen, Henry
2013-01-01
Bullying has extended beyond the schoolyard into online forums in the form of cyberbullying. Cyberbullying is a growing concern due to the effect on its victims. Current studies focus on grades K-12; however, cyberbullying has entered the world of higher education. The focus of this study was to identify the existence of cyberbullying in higher…
Experimental investigation of 4-dimensional superspace crystals
International Nuclear Information System (INIS)
Rasing, T.; Janner, A.
1983-09-01
The symmetry of incommensurate crystals can be described by higher dimensional space groups in the so called superspace approach. The basic ideas are explained and used for showing that superspace groups provide an adequate frame for analyzing experimental results on incommensurate crystals