How Many Dimensions are There?
Rowlands, Peter
Dimensionality has been a much discussed subject since Minkowski formalized special relativity by extending 3D space to 4D space-time. However, there has never been any consensus on the number of dimensions that nature requires and there has been no explanation of why dimensions are needed at all. It is proposed here that dimensions originate in the theory of numbers, that extending the number of dimensions beyond the 3 required by Euclidean space necessarily requires a fundamental change in the meaning of the concept, and that, although various algebraic techniques allow such extension of dimensionality, the structures required always ensure that the number of dimensions and their fundamental characteristics remain ambiguous, leaving the final question unanswerable.
Flatland a journey of many dimensions
2007-01-01
"Flatland" is based on Edwin A. Abbott's classic novel : Flatland : a romance of many dimensions. Flatland is a world that exists entirely on a two-dimensional plane. All different kinds of shapes live, work and play in this world. The story follows Arthur Square (Martin Sheen) and his curious granddaughter Hex (Kristen Bell). When a mysterious visitor (Michael York) arrives from Spaceland, Arthur and Hex must come to terms with the truth of the third dimension, risking dire consequences from the evil Circles that have ruled Flatland for thousands of years. "Flatland" is an animated story that includes action, drama, and geometry lessons. This heartfelt movie challenges audiences to grasp the limitations of our own assumptions about reality, and to think about the idea of higher dimensions.
Parallel solutions of correlation dimension calculation
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
The calculation of correlation dimension is a key problem of the fractals. The standard algorithm requires O(N2) computations. The previous improvement methods endeavor to sequentially reduce redundant computation on condition that there are many different dimensional phase spaces, whose application area and performance improvement degree are limited. This paper presents two fast parallel algorithms: O(N2/p + logp) time p processors PRAM algorithm and O(N2/p) time p processors LARPBS algorithm. Analysis and results of numeric computation indicate that the speedup of parallel algorithms relative to sequence algorithms is efficient. Compared with the PRAM algorithm, The LARPBS algorithm is practical, optimally scalable and cost optimal.
Health care as a community good. Many dimensions, many communities, many views of justice.
Galarneau, Charlene A
2002-01-01
We often speak of health care as a social good. What kind of good it is--and what justice requires of us in making it available to the members of society--depends on how society understands it. Yet the value of health care may be understood in many different ways within society.
Exploring the many-body localization transition in two dimensions
Choi, Jae-yoon; Hild, Sebastian; Zeiher, Johannes; Schauß, Peter; Rubio-Abadal, Antonio; Yefsah, Tarik; Khemani, Vedika; Huse, David A.; Bloch, Immanuel; Gross, Christian
2016-06-01
A fundamental assumption in statistical physics is that generic closed quantum many-body systems thermalize under their own dynamics. Recently, the emergence of many-body localized systems has questioned this concept and challenged our understanding of the connection between statistical physics and quantum mechanics. Here we report on the observation of a many-body localization transition between thermal and localized phases for bosons in a two-dimensional disordered optical lattice. With our single-site–resolved measurements, we track the relaxation dynamics of an initially prepared out-of-equilibrium density pattern and find strong evidence for a diverging length scale when approaching the localization transition. Our experiments represent a demonstration and in-depth characterization of many-body localization in a regime not accessible with state-of-the-art simulations on classical computers.
Automatic Calculation of Dimension Chains in AutoCAD
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
In the course of mechanical part designing, process p lanning and assembling designing, we often have to calculate and analyse a dimen sion chain. Traditionally, a dimension chain is established and calculated m anually. With wide computer application in the field of mechanical design and ma nufacture, people began to use a computer to acquire and calculate a dimension c hain automatically. In reported work, a dimension chain can be established and c alculated automatically. However, dimension text value...
From few to many. Ultracold atoms in reduced dimensions
International Nuclear Information System (INIS)
This thesis reports on experimental studies exploring few and many-body physics of ultracold Bose and Fermi gases with reduced dimensionality. These experiments illustrate the versatility and great amount of control over the particle number, the interaction and other degrees of freedom, like the spin, that these generic quantum systems offer. In the first part of this thesis, we use quasi one-dimensional few-particle systems of one to ten fermionic atoms to investigate the crossover from few to many-body physics. This is achieved by measuring the interaction energy between a single impurity atom in a state vertical stroke ↓ right angle which repulsively interacts with an increasing number of majority atoms in a state vertical stroke ↑ right angle. We find that the system quickly approaches the results from the many-body theory, which describes the behavior of a single impurity immersed in a Fermi sea of an infinite number of majority particles. The second part of this thesis presents studies of the time evolution of a bosonic F=1 spinor BEC of 87Rb atoms. In this system, we investigate the emergence and coarsening of ferromagnetic spin textures from initially unmagnetized samples. While the ferromagnetic domains grow, we observe the development of a spin space anisotropy which is in agreement with the predicted phase-diagram. The last part of this thesis presents our first steps towards the investigation of phase coherence of quasi two-dimensional quantum gases in the crossover from bosonic molecules to fermionic atoms.
From few to many. Ultracold atoms in reduced dimensions
Energy Technology Data Exchange (ETDEWEB)
Wenz, Andre Niklas
2013-12-19
This thesis reports on experimental studies exploring few and many-body physics of ultracold Bose and Fermi gases with reduced dimensionality. These experiments illustrate the versatility and great amount of control over the particle number, the interaction and other degrees of freedom, like the spin, that these generic quantum systems offer. In the first part of this thesis, we use quasi one-dimensional few-particle systems of one to ten fermionic atoms to investigate the crossover from few to many-body physics. This is achieved by measuring the interaction energy between a single impurity atom in a state vertical stroke ↓ right angle which repulsively interacts with an increasing number of majority atoms in a state vertical stroke ↑ right angle. We find that the system quickly approaches the results from the many-body theory, which describes the behavior of a single impurity immersed in a Fermi sea of an infinite number of majority particles. The second part of this thesis presents studies of the time evolution of a bosonic F=1 spinor BEC of {sup 87}Rb atoms. In this system, we investigate the emergence and coarsening of ferromagnetic spin textures from initially unmagnetized samples. While the ferromagnetic domains grow, we observe the development of a spin space anisotropy which is in agreement with the predicted phase-diagram. The last part of this thesis presents our first steps towards the investigation of phase coherence of quasi two-dimensional quantum gases in the crossover from bosonic molecules to fermionic atoms.
Black holes in many dimensions at the CERN large Hadron collider testing critical string theory
Hewett, J L; Rizzo, T G; Hewett, JoAnne L.; Lillie, Ben; Rizzo, Thomas G.
2005-01-01
We consider black hole production at the CERN Large Hadron Collider (LHC) in a generic scenario with many extra dimensions where the standard model fields are confined to a brane. With ~20 dimensions the hierarchy problem is shown to be naturally solved without the need for large compactification radii. We find that in such a scenario the properties of black holes can be used to determine the number of extra dimensions, n. In particular, we demonstrate that measurements of the decay distributions of such black holes at the LHC can determine if n is significantly larger than 6 or 7 with high confidence and thus can probe one of the critical properties of string theory compactifications.
Black holes in many dimensions at the CERN Large Hadron Collider: testing critical string theory.
Hewett, JoAnne L; Lillie, Ben; Rizzo, Thomas G
2005-12-31
We consider black hole production at the CERN Large Hadron Collider (LHC) in a generic scenario with many extra dimensions where the standard model fields are confined to a brane. With approximately 20 dimensions the hierarchy problem is shown to be naturally solved without the need for large compactification radii. We find that in such a scenario the properties of black holes can be used to determine the number of extra dimensions, . In particular, we demonstrate that measurements of the decay distributions of such black holes at the LHC can determine if is significantly larger than 6 or 7 with high confidence and thus can probe one of the critical properties of string theory compactifications.
Factorization in large-scale many-body calculations
Johnson, Calvin W.; Ormand, W. Erich; Krastev, Plamen G.
2013-01-01
One approach for solving interacting many-fermion systems is the configuration-interaction method, also sometimes called the interacting shell model, where one finds eigenvalues of the Hamiltonian in a many-body basis of Slater determinants (antisymmeterized products of single-particle wavefunctions). The resulting Hamiltonian matrix is typically very sparse, but for large systems the nonzero matrix elements can nonetheless require terabytes or more of storage. An alternate algorithm, applica...
The many dimensions of child poverty: Evidence from the UK Millennium Cohort Study
Dickerson, A.P.; Popli, G.
2015-01-01
In this paper we use a multidimensional framework to characterise child poverty in the UK. We examine the interdependencies amongst the different dimensions of multidimensional poverty, and the relationship of multidimensional poverty with income poverty. We also explore the links between multidimensional poverty, income poverty, and children's cognitive and non-cognitive development. Our findings suggest that multidimensional poverty identifies many but not all of the same children classifie...
The many-body problem an encyclopedia of exactly solved models in one dimension
1993-01-01
This book differs from its predecessor, Lieb & Mattis Mathematical Physics in One Dimension, in a number of important ways. Classic discoveries which once had to be omitted owing to lack of space - such as the seminal paper by Fermi, Pasta and Ulam on lack of ergodicity of the linear chain, or Bethe's original paper on the Bethe ansatz - can now be incorporated. Many applications which did not even exist in 1966 (some of which were originally spawned by the publication of Lieb & Mattis) are newly included. Among these, this new book contains critical surveys of a number of important developmen
Many-particle Systems in One Dimension in the Harmonic Approximation
DEFF Research Database (Denmark)
R. Armstrong, J.; Zinner, Nikolaj Thomas; V. Fedorov, D.;
2012-01-01
We consider energetics and structural properties of a many particle system in one dimension with pairwise contact interactions confined in a parabolic external potential. To render the problem analytically solvable, we use the harmonic approximation scheme at the level of the Hamiltonian. We...... investigate the scaling with particle number of the ground state energies for systems consisting of identical bosons or fermions. We then proceed to focus on bosonic systems and make a detailed comparison to known exact results in the absence of the parabolic external trap for three-body systems. We also...
The anomalous dimension of spin-1/2 baryons in many flavors QCD
Vecchi, Luca
2016-01-01
We derive the anomalous dimension of spin-1/2 baryon operators in QCD at leading 1/Nf order. Within this approximation the complication resulting from the mixing with an infinite number of evanescent operators can be easily bypassed.
Analysis of the Many-Body Problem in One Dimension with Repulsive Delta-Function Interaction
Albertsson, Martin
2014-01-01
The repulsive delta-function interaction model in one dimension is reviewed for spinless particles and for spin-1/2 fermions. The problem of solving the differential equation related to the Schrödinger equation is reduced by the Bethe ansatz to a system of algebraic equations. The delta-function interaction is shown to have no effect on spinless fermions which therefore behave like free fermions, in agreement with Pauli's exclusion principle. The ground-state problem of spinless bosons is red...
Dynamic, scalable and flexible resource discovery for large-dimension many-core systems
Zarrin, Javad; Barraca, João Paulo; Aguiar, Rui L.
2015-01-01
Future large scale systems will execute novel operating systems running across many chips with many cores. In this highly distributed environment, resource discovery is an important building block. Resource discovery aims to match the application’s demands to the existing (distributed) resources, by discovering and finding resources at run-time, and then selecting the best resource that matches the application running requirements. The main contribution of this paper is the design and evoluti...
Understanding many-body physics in one dimension from the Lieb-Liniger model
Jiang, Yu-Zhu; Chen, Yang-Yang; Guan, Xi-Wen
2015-05-01
This article presents an elementary introduction on various aspects of the prototypical integrable model the Lieb-Liniger Bose gas ranging from the cooperative to the collective features of many-body phenomena. In 1963, Lieb and Liniger first solved this quantum field theory many-body problem using Bethe’s hypothesis, i.e., a particular form of wavefunction introduced by Bethe in solving the one-dimensional Heisenberg model in 1931. Despite the Lieb-Liniger model is arguably the simplest exactly solvable model, it exhibits rich quantum many-body physics in terms of the aspects of mathematical integrability and physical universality. Moreover, the Yang-Yang grand canonical ensemble description for the model provides us with a deep understanding of quantum statistics, thermodynamics, and quantum critical phenomena at the many-body physical level. Recently, such fundamental physics of this exactly solved model has been attracting growing interest in experiments. Since 2004, there have been more than 20 experimental papers that reported novel observations of different physical aspects of the Lieb-Liniger model in the laboratory. So far the observed results are in excellent agreement with results obtained using the analysis of this simplest exactly solved model. Those experimental observations reveal the unique beauty of integrability. Project supported by the National Basic Research Program of China (Grant No. 2012CB922101) and the National Natural Science Foundation of China (Grant Nos. 11374331 and 11304357).
Exploring the few- to many-body crossover using cold atoms in one dimension
DEFF Research Database (Denmark)
Zinner, Nikolaj Thomas
2016-01-01
-matter or high-energy physics, i.e. we are on the verge of a 'cool' quantum simulator as envisioned by Feynman. One of the avenues under exploration is the physics of one-dimensional systems. Until recently this was mostly in the many-body limit but now experiments can be performed with controllable particle...
Polarization measurement and inference in many dimensions when subgroups can not be identified
Anderson, Gordon
2011-01-01
The most popular general univariate polarization indexes for discrete and continuous variables are extended and combined to describe the extent of polarization between agents in a distribution defined over a collection of many discrete and continuous agent characteristics. A formula for the asymptotic variance of the index is also provided. The implementation of the index is illustrated with an application to Chinese urban household data drawn from six provinces in the years 1987 and 2001 (ye...
Relativistic multireference many-body perturbation theory calculations on Au64+ - Au69+ ions
Energy Technology Data Exchange (ETDEWEB)
Vilkas, M J; Ishikawa, Y; Trabert, E
2006-03-31
Many-body perturbation theory (MBPT) calculations are an adequate tool for the description of the structure of highly charged multi-electron ions and for the analysis of their spectra. They demonstrate this by way of a re-investigation of n=3, {Delta}n=0 transitions in the EUV spectra of Na-, Mg-, Al-like, and Si-like ions of Au that have been obtained previously by heavy-ion accelerator based beam-foil spectroscopy. They discuss the evidence and propose several revisions on the basis of the multi-reference many-body perturbation theory calculations of Ne- through P-like ions of Au.
Exploring the few- to many-body crossover using cold atoms in one dimension
Directory of Open Access Journals (Sweden)
Zinner Nikolaj Thomas
2016-01-01
Full Text Available Cold atomic gases have provided us with a great number of opportunities for studying various physical systems under controlled conditions that are seldom offered in other fields. We are thus at the point where one can truly do quantum simulation of models that are relevant for instance in condensed-matter or high-energy physics, i.e. we are on the verge of a ’cool’ quantum simulator as envisioned by Feynman. One of the avenues under exploration is the physics of one-dimensional systems. Until recently this was mostly in the many-body limit but now experiments can be performed with controllable particle numbers all the way down to the few-body regime. After a brief introduction to some of the relevant experiments, I will review recent theoretical work on one-dimensional quantum systems containing bosons, fermions, or mixtures of the two, with a particular emphasis on the case where the particles are held by an external trap.
CALCULATION OF MILL RIGIDITY BY THREE DIMENSION CONTACT BOUNDARY ELEMENT METHOD
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
Vertical rigidity of the space self-adaptive 530 high rigidity mill is calculated by applying the boundary element method (BEM) of three-dimension elastic contact problem,which can update the existed deforming separation calculating theory and corresponding methods of material mechanics,elastic mechanics and finite element method.The method has less hypotheses and stronger synthesis in contact-type calculating model.The advantages of the method are high calculating rate,high calculating accuracy,etc..
Many-body theory calculations of positron binding to negative ions
Ludlow, J. A.; Gribakin, G. F.
2010-01-01
A many-body theory approach developed by the authors [Phys. Rev. A 70, 032720 (2004)] is applied to positron bound states and annihilation rates in atomic systems. Within the formalism, full account of virtual positronium (Ps) formation is made by summing the electron-positron ladder diagram series, thus enabling the theory to include all important many-body correlation effects in the positron problem. Numerical calculations have been performed for positron bound states with the hydrogen and ...
International Nuclear Information System (INIS)
Energy levels, line strengths, oscillator strengths, and transition rates are calculated for electric dipole nl1nl2[LSJ]-nl3nl4[L'S'J'] transition in Be- (n=2), Mg- (n=3), Zn- (n=4) and Sm- (n=5) like ions with nuclear charges ranging from Z=N to 100 where N is number of electron in system. (author)
Energy Technology Data Exchange (ETDEWEB)
Safronova, U.I.; Johnson, W.R. [Dept. of Physics, Univ. of Notre Dame, IN (United States)
2000-01-01
Energy levels, line strengths, oscillator strengths, and transition rates are calculated for electric dipole nl{sub 1}nl{sub 2}[LSJ]-nl{sub 3}nl{sub 4}[L'S'J'] transition in Be- (n=2), Mg- (n=3), Zn- (n=4) and Sm- (n=5) like ions with nuclear charges ranging from Z=N to 100 where N is number of electron in system. (author)
Grid-based density functional calculation of many-electron systems
Roy, Amlan K
2010-01-01
Exploratory variational pseudopotential density functional calculations are performed for the electronic properties of many-electron systems in the 3D cartesian coordinate grid (CCG). The atom-centered localized gaussian basis set, electronic density and the two-body potentials are set up in the 3D cubic box. The classical Hartree potential is calculated accurately and efficiently through a Fourier convolution technique. As a first step, simple local density functionals of homogeneous electron gas are used for the exchange-correlation potential, while Hay-Wadt-type effective core potentials are employed to eliminate the core electrons. No auxiliary basis set is invoked. Preliminary illustrative calculations on total energies, individual energy components, eigenvalues, potential energy curves, ionization energies, atomization energies of a set of 12 molecules show excellent agreement with the corresponding reference values of atom-centered grid as well as the grid-free calculation. Results for 3 atoms are also...
International Nuclear Information System (INIS)
Non-relativistic many-body perturbation theory is discussed. Methods and results in the solution of inhomogeneous 1- and 2-particle equations are presented. B. Similar programs for the Dirac equation are considered. The 1-particle equation is equivalent to the relativistic random phase approximation (work by A.-M. Martensson-Pendrill), and the 2-particle equation is under study. C. Matrix diagonalization of the Dirac equation is being explored as a method of isolating positive energy solutions. For a weak external field, the upper components of the diagonal equation correspond to positive energy solutions
Ground-state-energy theorem and the virial theorem of a many-particle system in d dimensions
Iwamoto, N.
1984-01-01
The equivalence of Pauli's ground-state-energy theorem and the virial theorem is demonstrated for a many-particle system interacting with an interparticle potential in d dimensions at zero and finite temperatures. Pauli's theorem has an integral form in which the variable is the coupling constant e-squared, while the virial theorem has a differential form in which the variable has the number density n. The essence of the equivalence proof consists in changing the variable from n to e-squared by noting the dependence of the excess free energy on dimensionless quantities for zero-temperature and classical cases.
Iha, Hisashi; Makino, Hiroki; Suzuki, Hiroshi
2016-05-01
We study four-dimensional conformal field theories with an SU(N) global symmetry by employing the numerical conformal bootstrap. We consider the crossing relation associated with a four-point function of a spin 0 operator φ _i^{bar {k}} which belongs to the adjoint representation of SU(N). For N=12 for example, we found that the theory contains a spin 0 SU(12)-breaking relevant operator when the scaling dimension of φ _i^{bar {k}}, Δ _{φ _i^{bar {k}}}, is smaller than 1.71. Considering the lattice simulation of many-flavor quantum chromodynamics with 12 flavors on the basis of the staggered fermion, the above SU(12)-breaking relevant operator, if it exists, would be induced by the flavor-breaking effect of the staggered fermion and prevent an approach to an infrared fixed point. Actual lattice simulations do not show such signs. Thus, assuming the absence of the above SU(12)-breaking relevant operator, we have an upper bound on the mass anomalous dimension at the fixed point γ _m^*≤ 1.29 from the relation γ _m^*=3-Δ _{φ _i^{bar {k}}}. Our upper bound is not so strong practically but it is strict within the numerical accuracy. We also find a kink-like behavior in the boundary curve for the scaling dimension of another SU(12)-breaking operator.
Energy Technology Data Exchange (ETDEWEB)
Villela, Anderson Goncalves; Carvalho, Valdivino Alves de [AES Eletropaulo, SP (Brazil)
2010-10-15
The calculation algorithm adopted by the AES Eletropaulo, Brazil, for the dimensioning of LV transformers did not represent the real grid conditions, being necessary the development of a new method. This paper presents the new procedure, based on the application of typical load curves and the consumption of energy calculation based on the load information supplied by clients and designers. (author)
Insights inot the atomic many-particle dynamics of scattering processes by ab-initio calculations
International Nuclear Information System (INIS)
The present thesis gives a theoretical contribution to the understanding of the many-particle dynamics in inelastic ion-atom collisions. Many-electron dynamics in ion-helium collisions and proton-sodium collisions was theoretically studied. The description is based on the semiclassical approximation with the straight orbit for the projectile motion. The ion-atom collision problem is by this reduced to a time-dependent many-electron problem and in the non-relativistic approximation described by the time-dependent Schroedinger equation. The solution of the many-electron problem pursues in the framework of the time-dependent density functional theory. The time-dependent Schroedinger equation for the interacting many-electron problem is transformed to the system of the time-dependent Kohn-Sham equations and solved by the two-center-basis generator method. The unknown time-dependent exchange-correlation one-particle potential forces different approximation int he time-dependent Kohn-Shan scheme. In this thesis the model of the independent electrons was applied as basis model, in which the electron-electron correlation is consistently neglected in all parts and in all steps. Differential cross sections for different one- and two-electron processes were calculated in the so-called eikonal approximation for the collisional systems p-He, He2+-He, and Arq+-He (q=15-18)
An universal algorithm of calculating terms of atomic many-body perturbation theory
Dzuba, V A
2007-01-01
An algorithm, based on numerical description of the terms of many-body perturbation theory (Goldstone diagrams), is presented. The algorithm assumes a basis set of orthogonal single-electron orbitals supplied by the user. These orbitals are the eigenstates of the Dirac operator in the spherically-symmetric case. Apart from this the algorithm is practically free from any limitations and can be used for calculating of wide range of atomic properties in any order of the perturbation theory and with any external field applied to the atom. The use of the algorithm is illustrated by calculating of the second and third order correlation corrections to the ground state energies of sodium, copper and gallium.
Iha, Hisashi; Suzuki, Hiroshi
2016-01-01
We study four-dimensional conformal field theories with an $SU(N)$ global symmetry by employing the numerical conformal bootstrap. We consider the crossing relation associated with a four-point function of a spin~$0$ operator~$\\phi_i^{\\Bar{k}}$ which belongs to the adjoint representation of~$SU(N)$. For~$N=12$ for example, we found that the theory contains a spin~$0$ $SU(12)$-breaking relevant operator if the scaling dimension of~$\\phi_i^{\\Bar{k}}$, $\\Delta_{\\phi_i^{\\Bar{k}}}$, is smaller than~$1.63$. Considering the lattice simulation of the many-flavor QCD with $12$~flavors on the basis of the staggered fermion, the above $SU(12)$-breaking relevant operator, if it exists, would be induced by the flavor breaking effect of the staggered fermion and would prevent an approach to an infrared fixed point. Actual lattice simulations do not show such signs. Thus, assuming the absence of the above $SU(12)$-breaking relevant operator, we have an upper bound on the mass anomalous dimension at the fixed point~$\\gamma_m...
Relativistic many-body calculations of energies for n=3 states in aluminiumlike ions
Energy Technology Data Exchange (ETDEWEB)
Safronova, U.I.; Namba, C. [National Inst. for Fusion Science, Toki, Gifu (Japan); Johnson, W.R.; Safronova, M.S. [Department of Physics, Univ. of Notre Dame, Notre Dame, IN (United States)
2001-01-01
Energies of the 148 (3l3l'3l'') states for aluminiumlike ions with Z =14-100 are evaluated to second order in relativistic many-body perturbation theory. Second-order Coulomb and Breit-Coulomb interactions are included. Corrections are made to lowest order for the frequency-dependent Breit interaction and for the Lamb shift. A detailed discussion of the various contributions to the energy levels is given for aluminiumlike germanium (Z=32). Comparisons of the calculated energy levels with available experimental data are made for the entire sequence. (author)
Many-body theory calculations of positron binding to negative ions
Ludlow, J A
2010-01-01
A many-body theory approach developed by the authors [Phys. Rev. A 70, 032720 (2004)] is applied to positron bound states and annihilation rates in atomic systems. Within the formalism, full account of virtual positronium (Ps) formation is made by summing the electron-positron ladder diagram series, thus enabling the theory to include all important many-body correlation effects in the positron problem. Numerical calculations have been performed for positron bound states with the hydrogen and halogen negative ions, also known as Ps hydride and Ps halides. The Ps binding energies of 1.118, 2.718, 2.245, 1.873 and 1.393 eV and annihilation rates of 2.544, 2.482, 1.984, 1.913 and 1.809 ns$^{-1}$, have been obtained for PsH, PsF, PsCl, PsBr and PsI, respectively.
Ab initio calculations of many-body interactions for compressed solid argon.
Tian, Chunling; Liu, Fusheng; Cai, Lingcang; Yuan, Hongkuan; Chen, Hong; Zhong, Mingmin
2015-11-01
An investigation on many-body effects of solid argon at high pressure was conducted based on a many-body expansion of interaction energy. The three- and four-body terms in the expansion were calculated using the coupled-cluster method with single, double, and noniterative triple theory and incremental method, in which the configurations of argon trimers and tetramers were chosen as the same as those in the actual lattice. The four-body interactions in compressed solid argon were estimated for the first time, and the three-body interaction ab initio calculations were extended to a small distance. It shows that the four-body contribution is repulsive at high densities and effectively cancels the three-body lattice energy. The dimer potential plus three-body interaction can well reproduce the measurements of equation of state at pressure approximately lower than ∼60 GPa, when including the four-body effects extends the agreement up to the maximum experimental pressure of 114 GPa. PMID:26547175
Elward, Jennifer M; Chakraborty, Arindam
2012-01-01
The congruent transformation of the electronic Hamiltonian is developed to address the electron correlation problem in many-electron systems. The central strategy presented in this method is to perform transformation on the electronic Hamiltonian for approximate removal of the Coulomb singularity. The principle difference between the present method and the transcorrelated method of Handy and Boys is that the congruent transformation preserves the Hermitian property of the Hamiltonian. The congruent transformation is carried out using explicitly correlated functions and the optimum correlated transform Hamiltonian is obtained by performing a search over a set of transformation functions. The ansatz of the transformation functions are selected to facilitate analytical evaluation of all the resulting integrals. The ground state energy is obtained variationally by performing a full configuration interaction (FCI) calculation on the congruent transformed Hamiltonian. Computed results on well-studied benchmark syst...
Ab initio many-body calculations of nucleon-nucleus scattering
Quaglioni, Sofia
2009-01-01
We develop a new ab initio many-body approach capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group method with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters. This approach preserves translational symmetry and Pauli principle. We outline technical details and present phase shift results for neutron scattering on 3H, 4He and 10Be and proton scattering on 3He and 4He, using realistic nucleon-nucleon (NN) potentials. Our A=4 scattering results are compared to earlier ab initio calculations. We find that the CD-Bonn NN potential in particular provides an excellent description of nucleon-4He S-wave phase shifts. On the contrary, the experimental nucleon-4He P-wave phase shifts are not well reproduced by any NN potential we use. We demonstrate that a proper treatment of the coupling to the n-10Be continuum is successful in explaining the parity-inverted ground state in 11Be.
How Many Dimensions Does It Take To Measure Users' Perceptions of Libraries?: A LibQUAL+Study.
Thompson, Bruce; Cook, Colleen; Heath, Fred
2001-01-01
Explores the number of dimensions needed to measure users' perceptions of library service quality based on data from the ARL (Association of Research Libraries) LibQUAL+ project. Results were consistent with a view that a single set of scores is one reasonable way to characterize user perceptions of library service quality. (Author/LRW)
Many-body effects on graphene conductivity: Quantum Monte Carlo calculations
Boyda, D. L.; Braguta, V. V.; Katsnelson, M. I.; Ulybyshev, M. V.
2016-08-01
Optical conductivity of graphene is studied using quantum Monte Carlo calculations. We start from a Euclidean current-current correlator and extract σ (ω ) from Green-Kubo relations using the Backus-Gilbert method. Calculations were performed both for long-range interactions and taking into account only the contact term. In both cases we vary interaction strength and study its influence on optical conductivity. We compare our results with previous theoretical calculations choosing ω ≈κ , thus working in the region of the plateau in σ (ω ) which corresponds to optical conductivity of Dirac quasiparticles. No dependence of optical conductivity on interaction strength is observed unless we approach the antiferromagnetic phase transition in the case of an artificially enhanced contact term. Our results strongly support previous theoretical studies that claimed very weak regularization of graphene conductivity.
Ho, H C; Blundell, S A; Safronova, M S
2006-01-01
Relativistic third-order MBPT is applied to obtain energies of ions with two valence electrons in the no virtual-pair approximation (NVPA). A total of 302 third-order Goldstone diagrams are organized into 12 one-body and 23 two-body terms. Only third-order two-body terms and diagrams are presented here, owing to the fact that the one-body terms are identical to the previously studied third-order terms in monovalent ions. Dominant classes of diagrams are identified. The model potential is a Dirac-Hartree-Fock $V^{N-2}$ potential, and B-spline basis functions in a cavity of finite radius are employed in the numerical calculations. The Breit interaction is taken into account through second order of perturbation theory and the lowest-order Lamb shift is also evaluated. Sample calculations are performed for berylliumlike ions with Z = 4--7, and for the magnesiumlike ion P IV. The third-order energies are in excellent agreement with measurement with an accuracy at 0.2% level for the cases considered. Comparisons ar...
Many-body electronic structure calculations of Eu-doped ZnO
Lorke, M.; Frauenheim, T.; da Rosa, A. L.
2016-03-01
The formation energies and electronic structure of europium-doped zinc oxide has been determined using DFT and many-body G W methods. In the absence of intrisic defects, we find that the europium-f states are located in the ZnO band gap with europium possessing a formal charge of 2+. On the other hand, the presence of intrinsic defects in ZnO allows intraband f -f transitions otherwise forbidden in atomic europium. This result corroborates with recently observed photoluminescence in the visible red region S. Geburt et al. [Nano Lett. 14, 4523 (2014), 10.1021/nl5015553].
Density functional calculation of many-electron systems in cartesian coordinate grid
Roy, Amlan K
2011-01-01
A recently developed density functional method, within Hohenberg-Kohn-Sham framework, is used for faithful description of atoms, molecules in Cartesian coordinate grid, by using an LCAO-MO ansatz. Classical Coulomb potential is obtained by means of a Fourier convolution technique. All two-body potentials (including exchange-correlation (XC)) are constructed directly on real grid, while their corresponding matrix elements are computed from numerical integration. Detailed systematic investigation is made for a representative set of atoms/molecules through a number of properties like total energies, component energies, ionization energies, orbital energies, etc. Two nonlocal XC functionals (FT97 and PBE) are considered for pseudopotential calculation of 35 species while preliminary all-electron results are reported for 6 atoms using the LDA XC density functional. Comparison with literature results, wherever possible, exhibits near-complete agreement. This offers a simple efficient route towards accurate reliable...
Excitonic effects in GeC hybrid: Many-body Green's function calculations
Drissi, L. B.; Ramadan, F. Z.
2015-11-01
Many-body effects on the electronic and optical absorption properties of a GeC sheet are studied by means of first principle many-body Green's function and Bethe-Salpeter equation formalism. The absence of soft modes in the phonon-spectrum indicates the stability of the system. The inclusion of quasiparticle corrections increases significantly the band gap. The local field effects induce significant change in the absorption spectra for the out-plane polarization rendering the GeC monolayer transparent below 7 eV. The excitonic effects are significant on the optical absorption properties. A detailed analysis of the spectrum shows a strong binding energy of 1.82 eV assigned to the lowest-energy bound excitons that is characterized by an effective mass of 1.68m0 and a Bohr radius of 2 Å. The results of this study hold the promise for potential applications of the GeC hybrid in optoelectronics.
The coupled-cluster approach to non-relativistic and relativistic many-body calculations
International Nuclear Information System (INIS)
A review is given of the atomic many-body theory in the coupled-cluster approach or exponential-Ansatz formulation. Explicit equations and corresponding graphical representations are given in the pair-approximation, where the one- and two-body parts of the cluster (exponent) operator are considered. Also the effect of a small, additional perturbation is considered. The technique of evaluating diagrams by means of one- and two-particle functions, satisfying inhomogeneous differential equations, is reviewed. Illustrative numerical results are given for the electron correlation energy, electron binding energy, hyperfine separation and specific mass shift of simple atomic systems. The extension of the non-relativistic procedure to the relativistic regime is discussed by considering the effect of the exchange of one and two virtual, transverse photons between the electrons. In lowest order this leads to the ''no-virtual-pair approximation''. (orig.)
Ab initio many-body calculations of nucleon-4He scattering with three-nucleon forces
Hupin, Guillaume; Navrátil, Petr; Quaglioni, Sofia; Calci, Angelo; Roth, Robert
2013-01-01
We extend the ab initio no-core shell model/resonating-group method to include three-nucleon (3N) interactions for the description of nucleon-nucleus collisions. We outline the formalism, give algebraic expressions for the 3N-force integration kernels, and discuss computational aspects of two alternative implementations. The extended theoretical framework is then applied to nucleon-4He scattering using similarity-renormalization-group (SRG) evolved nucleon-nucleon plus three-nucleon potentials derived from chiral effective field theory. We analyze the convergence properties of the calculated phase shifts and explore their dependence upon the SRG evolution parameter. We include up to six excited states of the 4He target and find significant effects from the inclusion of the chiral 3N force, e.g., it enhances the spin-orbit splitting between the 3/2- and 1/2- resonances and leads to an improved agreement with the phase shifts obtained from an accurate R-matrix analysis of the five-nucleon experimental data. We ...
Thies, B.; Sepp, W.-D.; Fricke, B.
1989-07-01
The time dependence of a heavy-ion-atom collision system is solved via a set of coupled channel equations using energy eigen-values and matrix elements from a self-consistent field relativistic molecular many-electron Dirac-Fock-Slater calculation. Within this independent particle model we give a full many-particle interpretation by performing a small number of single-particle calculations. First results for the P( b) curves for the Ne K-hole excitation for the systems F 8+-Ne and F 6+-Ne as examples are discussed.
Propagation of chaos for many-boson systems in one dimension with a point pair-interaction
AMMARI, Zied; Breteaux, Sébastien
2012-01-01
35 pages International audience We consider the semiclassical limit of nonrelativistic quantum many-boson systems with delta potential in one dimensional space. We prove that time evolved coherent states behave semiclassically as squeezed states by a Bogoliubov time-dependent affine transformation. This allows us to obtain properties analogous to those proved by Hepp and Ginibre-Velo (\\cite{Hep}, \\cite{GiVe1,GiVe2}) and also to show propagation of chaos for Schrödinger dynamics in the m...
Energy Technology Data Exchange (ETDEWEB)
Benfatto, G. (Rome-2 Univ. (Italy). Dipt. di Matematica); Gallavotti, G. (Rome-1 Univ. (Italy). Dipt. di Fisica Rutgers Univ., New Brunswick, NJ (United States). Dept. of Mathematics); Procacci, A. (Rome-1 Univ. (Italy). Dipt. di Fisica); Scoppola, B. (Rome-1 Univ. (Italy). Dipt. di Matematica)
1994-02-01
We present a rigorous discussion of the analyticity properties of the beta function and of the effective potential for the theory of the ground state of a one dimensional system of many spinless fermions. We show that their analyticity domain as a function of the running couplings is a polydisk with positive radius bounded below, uniformly in all the cut offs (infrared and ultraviolet) necessary to give a meaning to the formal Schwinger functions. We also prove the vanishing of the scale independent part of the beta function showing that this implies the analyticity of the effective potential and of the Schwinger functions in terms of the bare coupling. Finally we show that the pair Schwinger function has an anomalous long distance behaviour. (orig.)
CPsup(N-1) model. Calculation of anomalous dimensions and mixing matrices in the 1/N order
Energy Technology Data Exchange (ETDEWEB)
Vasil' ev, A.N.; Nalimov, M.Yu. (Leningradskij Gosudarstvennyj Univ. (USSR))
1983-07-01
In the first order in 1/N and at the arbitrary spatial dimension 2
Coccia, Emanuele; Guidoni, Leonardo
2014-01-01
In this letter we report the singlet ground state structure of the full carotenoid peridinin by means of variational Monte Carlo (VMC) calculations. The VMC relaxed geometry has an average bond length alternation of 0.1165(10) {\\AA}, larger than the values obtained by DFT (PBE, B3LYP and CAM-B3LYP) and shorter than that calculated at the Hartree-Fock (HF) level. TDDFT and EOM-CCSD calculations on a reduced peridinin model confirm the HOMO-LUMO major contribution of the Bu+-like (S2) bright excited state. Many Body Green's Function Theory (MBGFT) calculations of the vertical excitation energy of the Bu+-like state for the VMC structure (VMC/MBGFT) provide excitation energy of 2.62 eV, in agreement with experimental results in n-hexane (2.72 eV). The dependence of the excitation energy on the bond length alternation in the MBGFT and TDDFT calculations with different functionals is discussed.
The many dimensions of interdisciplinarity
Jensen, Pablo; Paradzinets, Katsyarina
2013-01-01
Interdisciplinarity is as trendy as it is difficult to define. We propose three different operationalizations of a discipline and two levels (article or laboratory) of integration of these disciplines. This leads to six indicators of interdisciplinarity, achieving a rich characterization of laboratories publication practices. Thanks to a statistical analysis of these indicators on 600 CNRS laboratories, we suggest that, besides an average value of interdisciplinarity, different laboratories c...
International Nuclear Information System (INIS)
A method was developed to calculate the second dimension retention index of comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC/TOF MS) data using n-alkanes as reference compounds. The retention times of the C7-C31 alkanes acquired during 24 isothermal experiments cover the 0-6 s retention time area in the second dimension retention time space, which makes it possible to calculate the retention indices of target compounds from the corresponding retention time values without the extension of the retention space of the reference compounds. An empirical function was proposed to show the relationship among the second dimension retention time. the temperature of the second dimension column, and the carbon number of the n-alkanes. The proposed function is able to extend the second dimension retention time beyond the reference n-alkanes by increasing the carbon number. The extension of carbon numbers in reference n-alkanes up to two more carbon atoms introduces less than 10 retention index units (iu) of deviation. The effectiveness of using the proposed method was demonstrated by analyzing a mixture of compound standards in temperature programmed experiments using 6 different initial column temperatures. The standard deviation of the calculated retention index values of the compound standards fluctuated from 1 to 12 iu with a mean standard deviation of 5 iu. (authors)
Institute of Scientific and Technical Information of China (English)
沈晓华; 邹乐君; 李宏升; 沈忠悦; 杨树峰
2002-01-01
Fractal dimensions of a terrain quantitatively describe the self-organized structure of the terrain geometry. However, the local topographic variation cannot be illustrated by the conventional box-counting method. This paper proposes a successive shift box-counting method, in which the studied object is divided into small sub-objects that are composed of a series of grids according to its characteristic scaling. The terrain fractal dimensions in the grids are calculated with the successive shift box-counting method and the scattered points with values of fractal dimensions are obtained. The present research shows that the planar variation of fractal dimensions is well consistent with fault traces and geological boundaries.
Kong, Bo; Zhang, Yachao
2016-07-01
The electronic structures of the cubic GdH3 are extensively investigated using the ab initio many-body GW calculations treating the Gd 4f electrons either in the core (4f-core) or in the valence states (4f-val). Different degrees of quasiparticle (QP) self-consistent calculations with the different starting points are used to correct the failures of the GGA/GGA + U/HSE03 calculations. In the 4f-core case, GGA + G0W0 calculations give a fundamental band gap of 1.72 eV, while GGA+ GW0 or GGA + GW calculations present a larger band gap. In the 4f-val case, the nonlocal exchange-correlation (xc) functional HSE03 can account much better for the strong localization of the 4f states than the semilocal or Hubbard U corrected xc functional in the Kohn-Sham equation. We show that the fundamental gap of the antiferromagnetic (AFM) or ferromagnetic (FM) GdH3 can be opened up by solving the QP equation with improved starting point of eigenvalues and wave functions given by HSE03. The HSE03 + G0W0 calculations present a fundamental band gap of 2.73 eV in the AFM configuration, and the results of the corresponding GW0 and GW calculations are 2.89 and 3.03 eV, respectively. In general, for the cubic structure, the fundamental gap from G0W0 calculations in the 4f-core case is the closest to the real result. By G0W0 calculations in the 4f-core case, we find that H or Gd defects can strongly affect the band structure, especially the H defects. We explain the mechanism in terms of the possible electron correlation on the hydrogen site. Under compression, the insulator-to-metal transition in the cubic GdH3 occurs around 40 GPa, which might be a satisfied prediction.
Genovese, Luigi; Ospici, Matthieu; Deutsch, Thierry; Méhaut, Jean-François; Neelov, Alexey; Goedecker, Stefan
2009-07-21
We present the implementation of a full electronic structure calculation code on a hybrid parallel architecture with graphic processing units (GPUs). This implementation is performed on a free software code based on Daubechies wavelets. Such code shows very good performances, systematic convergence properties, and an excellent efficiency on parallel computers. Our GPU-based acceleration fully preserves all these properties. In particular, the code is able to run on many cores which may or may not have a GPU associated, and thus on parallel and massive parallel hybrid machines. With double precision calculations, we may achieve considerable speedup, between a factor of 20 for some operations and a factor of 6 for the whole density functional theory code.
Institute of Scientific and Technical Information of China (English)
GAO Ning; LAI Wen-Sheng
2006-01-01
@@ The calculation of elastic constants of Ag/Pd superlattice thin films by molecular dynamics simulations with many-body potentials is presented. It reveals that the elastic constants C11 and C55 increase with decreasing modulation wavelength A of the films, which is consistent with experiments. However, the change of C11 and C55 with A is found to be around the values determined by a rule of mixture using bulk elastic constants of metals.No supermodulus effect is observed and it is due to cancellation between enhanced and reduced contributions to elastic constants from Ag and Pd layers subjected to compressive and tensile strains, respectively.
DEFF Research Database (Denmark)
Jin, Chengjun; Markussen, Troels; Thygesen, Kristian Sommer
2014-01-01
We investigate the electronic conductance and thermopower of a single-molecule junction consisting of bis-(4-aminophenyl) acetylene (B4APA) connected to gold electrodes. We use nonequilibrium Green's function methods in combination with density-functional theory (DFT) and the many-body GW...... approximation. To simulate recent break junction experiments, we calculate the transport properties of the junction as it is pulled apart. For all junction configurations, DFT with a standard semilocal functional overestimates the conductance by almost an order of magnitude, while the thermopower...
$\\it{Ab}$ $\\it{initio}$ nuclear many-body perturbation calculations in the Hartree-Fock basis
Hu, Baishan; Sun, Zhonghao; Vary, James P; Li, Tong
2016-01-01
Starting from realistic nuclear forces, the chiral N$^3$LO and JISP16, we have applied many-body perturbation theory (MBPT) to the structure of closed-shell nuclei, $^4$He and $^{16}$O. The two-body N$^3$LO interaction is softened by a similarity renormalization group transformation while JISP16 is adopted without renormalization. The MBPT calculations are performed within the Hartree-Fock (HF) bases. The angular momentum coupled scheme is used, which can reduce the computational task. Corrections up to the third order in energy and up to the second order in radius are evaluated. Higher-order corrections in the HF basis are small relative to the leading-order perturbative result. Using the anti-symmetrized Goldstone diagram expansions of the wave function, we directly correct the one-body density for the calculation of the radius, rather than calculate corrections to the occupation propabilities of single-particle orbits as found in other treatments. We compare our results with other methods where available a...
Stoeckli, Fritz
2007-01-01
Two theoretical models are presented for the calculation of adsorption potentials in slot-like pores of molecular dimensions, with respect to the adsorption by a single flat surface. The cases of continuous and layer-like solids are considered, with interatomic pair-potentials of the 6:12 type, and for pore widths ranging from two to four times the equilibrium distance of adsorption. Both models give good results for the adsorption of simple molecules by microporous carbons and graphitized ca...
Calculation methods for SPF for heat pump systems for comparison, system choice and dimensioning
Energy Technology Data Exchange (ETDEWEB)
Nordman, Roger; Andersson, Kajsa; Axell, Monica; Lindahl, Markus
2010-09-15
In this project, results from field measurements of heat pumps have been collected and summarised. Also existing calculation methods have been compared and summarised. Analyses have been made on how the field measurements compare to existing calculation models for heat pumps Seasonal Performance Factor (SPF), and what deviations may depend on. Recommendations for new calculation models are proposed, which include combined systems (e.g. solar - HP), capacity controlled heat pumps and combined DHW and heating operation
Choi, Sunghwan; Kwon, Oh-Kyoung; Kim, Jaewook; Kim, Woo Youn
2016-09-15
We investigated the performance of heterogeneous computing with graphics processing units (GPUs) and many integrated core (MIC) with 20 CPU cores (20×CPU). As a practical example toward large scale electronic structure calculations using grid-based methods, we evaluated the Hartree potentials of silver nanoparticles with various sizes (3.1, 3.7, 4.9, 6.1, and 6.9 nm) via a direct integral method supported by the sinc basis set. The so-called work stealing scheduler was used for efficient heterogeneous computing via the balanced dynamic distribution of workloads between all processors on a given architecture without any prior information on their individual performances. 20×CPU + 1GPU was up to ∼1.5 and ∼3.1 times faster than 1GPU and 20×CPU, respectively. 20×CPU + 2GPU was ∼4.3 times faster than 20×CPU. The performance enhancement by CPU + MIC was considerably lower than expected because of the large initialization overhead of MIC, although its theoretical performance is similar with that of CPU + GPU. © 2016 Wiley Periodicals, Inc. PMID:27431905
Choi, Sunghwan; Kwon, Oh-Kyoung; Kim, Jaewook; Kim, Woo Youn
2016-09-15
We investigated the performance of heterogeneous computing with graphics processing units (GPUs) and many integrated core (MIC) with 20 CPU cores (20×CPU). As a practical example toward large scale electronic structure calculations using grid-based methods, we evaluated the Hartree potentials of silver nanoparticles with various sizes (3.1, 3.7, 4.9, 6.1, and 6.9 nm) via a direct integral method supported by the sinc basis set. The so-called work stealing scheduler was used for efficient heterogeneous computing via the balanced dynamic distribution of workloads between all processors on a given architecture without any prior information on their individual performances. 20×CPU + 1GPU was up to ∼1.5 and ∼3.1 times faster than 1GPU and 20×CPU, respectively. 20×CPU + 2GPU was ∼4.3 times faster than 20×CPU. The performance enhancement by CPU + MIC was considerably lower than expected because of the large initialization overhead of MIC, although its theoretical performance is similar with that of CPU + GPU. © 2016 Wiley Periodicals, Inc.
Energy Technology Data Exchange (ETDEWEB)
Moreira, Iberio de P R [Departament de Quimica Fisica and Institut de Quimica Teorica i Computacional (IQTCUB), Universitat de Barcelona and Parc CientIfic de Barcelona, C/ MartI i Franques 1, E-08028 Barcelona (Spain); Calzado, Carmen J [Departamento de Quimica Fisica, Universidad de Sevilla, C/ Prof. GarcIa Gonzalez s/n, E-41012 Sevilla (Spain); Malrieu, Jean-Paul [IRSAMC, Laboratoire de Physique Quantique, Universite Paul Sabatier, 118 Route de Narbonne, F-31062 Toulouse-Cedex (France); Illas, Francesc [Departament de Quimica Fisica and Institut de Quimica Teorica i Computacional (IQTCUB), Universitat de Barcelona and Parc CientIfic de Barcelona, C/ MartI i Franques 1, E-08028 Barcelona (Spain)
2007-10-15
A general procedure is presented which permits the form of an extended spin Hamiltonian to be established for a given magnetic solid and the magnitude of its terms to be evaluated from spin polarized, Hartree-Fock or density functional calculations carried out for periodic models. The computational strategy makes use of a general mapping between the energy of pertinent broken-symmetry solutions and the diagonal terms of the spin Hamiltonian in a local representation. From this mapping it is possible to determine not only the amplitude of the well-known two-body magnetic coupling constants between near-neighbor sites, but also the amplitudes of four-body cyclic exchange terms. A scrutiny of the on-site spin densities provides additional information and control of the many broken-symmetry solutions which can be found. The procedure is applied to the La{sub 2}CuO{sub 4}, Sr{sub 2}CuO{sub 2}F{sub 2}, Sr{sub 2}CuO{sub 2}Cl{sub 2} and Ca{sub 2}CuO{sub 2}Cl{sub 2} square lattices and the SrCu{sub 2}O{sub 3} ladder compound. It is shown that a proper description of the magnetic structure of these compounds requires that two- and four-body terms are explicitly included in the spin Hamiltonian. The implications for the interpretation of recent experiments are discussed.
Orthogonal polynomial approach to calculate the two-nucleon transition operator in three dimensions
Topolnicki, Kacper; Golak, Jacek; Skibiński, Roman; Witała, Henryk
2016-02-01
We give a short report on the possibility to use orthogonal polynomials (OP) in calculations that involve the two-nucleon (2N) transition operator. The presented work adds another approach to the set of previously developed methods (described in Phys. Rev. C 81, 034006 (2010); Few-Body Syst. 53, 237 (2012); K. Topolnicki, PhD thesis, Jagiellonian University (2014)) and is applied to the transition operator calculated at laboratory kinetic energy 300MeV. The new results for neutron-neutron and neutron-proton scattering observables converge to the results presented in Few-Body Syst. 53, 237 (2012) and to results obtained using the Arnoldi algorithm (Y. Saad, Iterative methods for sparse linear systems (SIAM Philadelphia, PA, USA 2003)). The numerical cost of the calculations performed using the new scheme is large and the new method can serve only as a backup to cross-check the previously used calculation schemes.
Orthogonal polynomial approach to calculate the two-nucleon transition operator in three dimensions
Energy Technology Data Exchange (ETDEWEB)
Topolnicki, Kacper; Golak, Jacek; Skibinski, Roman; Witala, Henryk [Jagiellonian University, M. Smoluchowski Institute of Physics, Krakow (Poland)
2016-02-15
We give a short report on the possibility to use orthogonal polynomials (OP) in calculations that involve the two-nucleon (2N) transition operator. The presented work adds another approach to the set of previously developed methods (described in Phys. Rev. C 81, 034006 (2010); Few-Body Syst. 53, 237 (2012); K. Topolnicki, PhD thesis, Jagiellonian University (2014)) and is applied to the transition operator calculated at laboratory kinetic energy 300MeV. The new results for neutron-neutron and neutron-proton scattering observables converge to the results presented in Few-Body Syst. 53, 237 (2012) and to results obtained using the Arnoldi algorithm (Y. Saad, Iterative methods for sparse linear systems (SIAM Philadelphia, PA, USA 2003)). The numerical cost of the calculations performed using the new scheme is large and the new method can serve only as a backup to cross-check the previously used calculation schemes. (orig.)
Many-hit model calculations for track etch rate in CR-39 SSNTD using confocal microscope data
Fromm, M.; Awad, E. M.; Ditlov, V.
2004-12-01
The present work studied an important part of ion tracks: the Bragg peak region. Information about the microscopic nature of ion-energy dissipation based on zero-approximation in frame of the many-hit model of the track structure theory was studied. The detector response, Vt, was calculated in terms of Poisson's distribution as a function of the ion's linear energy transfer (LET). This approach can be considered to be a zero-approximation since LET is a special case of restricted energy losses with a cut off energy wcutoff = ∞: LET = REL∞. Confocal microscopic data allows the visualising and analysing of the etched tracks one by one with high precision. A three-dimensional track image was observed and the track etch rate was measured. On the basis of χ2 analysis of the experimental track etch rate (square of the least deviation), with respect to that of the theoretical value, information about the energy transfer process can be obtained. Light ions of little MeV energy were slowed down in the CR-39 detector and the detectors responses close to the Bragg peak region were studied. It was shown that in the zero-approximation no one to one relation can be found between the primary linear energy transfer (LET) and the measured specific track etch rate. The statistical analysis can be split into two separate parts; before the Bragg peak (Bethe-Bloch) and after the Bragg peak (Thin Down). The two parts analysed reflect the separated domains where the etching rate increases or decreases, due to the different role of the delta-electrons in each of these domains. The main aim of this study is to develop a method for any ion describing Vt in this very sensitive Bragg region. This would allow ion identification at low velocities on the one hand, and on the other hand to have a better understanding of the physical processes involved during high velocity ion stopping.
Energy Technology Data Exchange (ETDEWEB)
Vilkas, M J; Ishikawa, Y; Trabert, E
2007-03-27
Relativistic multireference many-body perturbation theory calculations have been performed on Xe{sup 43+}-Xe{sup 39+} ions, resulting in energy levels, electric dipole transition probabilities, and level lifetimes. The second-order many-body perturbation theory calculation of energy levels included mass shifts, frequency-dependent Breit correction and Lamb shifts. The calculated transition energies and E1 transition rates are used to present synthetic spectra in the extreme ultraviolet range for some of the Xe ions.
Boyd, O.S.
2006-01-01
We have created a second-order finite-difference solution to the anisotropic elastic wave equation in three dimensions and implemented the solution as an efficient Matlab script. This program allows the user to generate synthetic seismograms for three-dimensional anisotropic earth structure. The code was written for teleseismic wave propagation in the 1-0.1 Hz frequency range but is of general utility and can be used at all scales of space and time. This program was created to help distinguish among various types of lithospheric structure given the uneven distribution of sources and receivers commonly utilized in passive source seismology. Several successful implementations have resulted in a better appreciation for subduction zone structure, the fate of a transform fault with depth, lithospheric delamination, and the effects of wavefield focusing and defocusing on attenuation. Companion scripts are provided which help the user prepare input to the finite-difference solution. Boundary conditions including specification of the initial wavefield, absorption and two types of reflection are available. ?? 2005 Elsevier Ltd. All rights reserved.
Calculation of the one-dimension two energy groups lambda modes, using the boundary functions method
International Nuclear Information System (INIS)
Using parameters and cross sections of SIMULATE-III code, a method to obtain the lambda modes was developed. In order to validate the method, eigenvalues and eigenfunctions obtained with this method were compared with those obtained using SIMULATE III and VENTURE codes. For superior order modes, the results were compared with those calculated by General Electric, for the Cofrentes Nuclear Power Plant-Spain. (author)
FORTRAN programs for calculating nonlinear seismic ground response in two dimensions
Joyner, W.B.
1978-01-01
The programs described here were designed for calculating the nonlinear seismic response of a two-dimensional configuration of soil underlain by a semi-infinite elastic medium representing bedrock. There are two programs. One is for plane strain motions, that is, motions in the plane perpendicular to the long axis of the structure, and the other is for antiplane strain motions, that is motions parallel to the axis. The seismic input is provided by specifying what the motion of the rock-soil boundary would be if the soil were absent and the boundary were a free surface. This may be done by supplying a magnetic tape containing the values of particle velocity for every boundary point at every instant of time. Alternatively, a punch card deck may be supplied giving acceleration values at every instant of time. In the plane strain program it is assumed that the acceleration values apply simultaneously to every point on the boundary; in the antiplane strain program it is assumed that the acceleration values characterize a plane shear wave propagating upward in the underlying elastic medium at a specified angle with the vertical. The nonlinear hysteretic behavior of the soil is represented by a three-dimensional rheological model. A boundary condition is used which takes account of finite rigidity in the elastic substratum. The computations are performed by an explicit finite-difference scheme that proceeds step by step in space and time. Computations are done in terms of stress departures from an unspecified initial state. Source listings are provided here along with instructions for preparing the input. A more detailed discussion of the method is presented elsewhere.
Li, Yanwei; Zhang, Ruiming; Du, Likai; Zhang, Qingzhu; Wang, Wenxing
2016-01-01
The quantum mechanics/molecular mechanics (QM/MM) method (e.g., density functional theory (DFT)/MM) is important in elucidating enzymatic mechanisms. It is indispensable to study "multiple" conformations of enzymes to get unbiased energetic and structural results. One challenging problem, however, is to determine the minimum number of conformations for DFT/MM calculations. Here, we propose two convergence criteria, namely the Boltzmann-weighted average barrier and the disproportionate effect, to tentatively address this issue. The criteria were tested by defluorination reaction catalyzed by fluoroacetate dehalogenase. The results suggest that at least 20 conformations of enzymatic residues are required for convergence using DFT/MM calculations. We also tested the correlation of energy barriers between small QM regions and big QM regions. A roughly positive correlation was found. This kind of correlation has not been reported in the literature. The correlation inspires us to propose a protocol for more efficient sampling. This saves 50% of the computational cost in our current case. PMID:27556449
Relativistic many-body calculations of van der Waals coefficients for Yb-Li and Yb-Rb dimers
Porsev, S G; Derevianko, A; Clark, Charles W
2014-01-01
We derive the relativistic formulas for the van der Waals coefficients of Yb-alkali dimers that correlate to ground and excited separated-atom limits. We calculate $C_6$ and $C_8$ coefficients of particular experimental interest. We also derive a semi-empirical formula that expresses the $C_8$ coefficient of heteronuclear $A+B$ dimers in terms of the $C_6$ and $C_8$ coefficients of homonuclear dimers and the static dipole and quadrupole polarizabilities of the atomic states $A$ and $B$. We report results of calculation of the $C_6$ coefficients for the Yb-Rb $^3/!P_1^o+5s\\, ^2/!S_{1/2}$ and $^1/!S_0+5p\\, ^2/!P^o_{1/2}$ dimers, and the $C_8$ coefficients for the Yb-Li $^1/!S_0+2s\\, ^2/!S_{1/2}$ and Yb-Rb $^1/!S_0+5s\\, ^2/!S_{1/2}$ dimers. Uncertainties are estimated for all predicted properties.
Directory of Open Access Journals (Sweden)
Yanwei Li
2016-08-01
Full Text Available The quantum mechanics/molecular mechanics (QM/MM method (e.g., density functional theory (DFT/MM is important in elucidating enzymatic mechanisms. It is indispensable to study “multiple” conformations of enzymes to get unbiased energetic and structural results. One challenging problem, however, is to determine the minimum number of conformations for DFT/MM calculations. Here, we propose two convergence criteria, namely the Boltzmann-weighted average barrier and the disproportionate effect, to tentatively address this issue. The criteria were tested by defluorination reaction catalyzed by fluoroacetate dehalogenase. The results suggest that at least 20 conformations of enzymatic residues are required for convergence using DFT/MM calculations. We also tested the correlation of energy barriers between small QM regions and big QM regions. A roughly positive correlation was found. This kind of correlation has not been reported in the literature. The correlation inspires us to propose a protocol for more efficient sampling. This saves 50% of the computational cost in our current case.
Safronova, U I; Johnson, W R
2016-01-01
Energy levels of 30 low-lying states of Lu2+ and allowed electric-dipole matrix elements between these states are evaluated using a relativistic all-order method in which all single, double and partial triple excitations of Dirac-Fock wave functions are included to all orders of perturbation theory. Matrix elements are critically evaluated for their accuracy and recommended values of the matrix elements are given together with uncertainty estimates. Line strengths, transition rates and lifetimes of the metastable 5d(3/2) and 5d(5/2) states are calculated. Recommended values are given for static polarizabilities of the 6s, 5d and 6p states and tensor polarizabilities of the 5d and 6p(3/2) states. Uncertainties of the polarizability values are estimated in all cases. The blackbody radiation shift of the 6s(1/2)-5d(5/2) transition frequency of the Lu2+ ion is calculated with the aid of the recommended scalar polarizabilities of the 6s(1/2) and 5d(5/2) states. Finally, A and B hyperfine constants are determined f...
Safronova, U. I.; Safronova, M. S.; Johnson, W. R.
2016-09-01
Energy levels of 30 low-lying states of Lu2 + and allowed electric-dipole matrix elements between these states are evaluated using a relativistic all-order method in which all single, double, and partial triple excitations of Dirac-Fock wave functions are included to all orders of perturbation theory. Matrix elements are critically evaluated for their accuracy and recommended values of the matrix elements are given together with uncertainty estimates. Line strengths, transition rates, and lifetimes of the metastable 5 d3 /2 and 5 d5 /2 states are calculated. Recommended values are given for static polarizabilities of the 6 s , 5 d , and 6 p states and tensor polarizabilities of the 5 d and 6 p3 /2 states. Uncertainties of the polarizability values are estimated in all cases. The blackbody radiation shift of the 6 s1 /2-5 d5 /2 transition frequency of the Lu2 + ion is calculated with the aid of the recommended scalar polarizabilities of the 6 s1 /2 and 5 d5 /2 states. Finally, A and B hyperfine constants are determined for states of 2+175Lu with n ≤9 . This work provides recommended values of transition matrix elements, polarizabilities, and hyperfine constants of Lu2 +, critically evaluated for accuracy, for benchmark tests of high-precision theoretical methodology and planning of future experiments.
Porter, Troy A
2013-01-01
Cosmic dust particles effectively attenuate starlight. Their absorption of starlight produces emission spectra from the near- to far-infrared, which depends on the sizes and properties of the dust grains, and spectrum of the heating radiation field. The near- to mid-infrared is dominated by the emissions by very small grains. Modeling the absorption of starlight by these particles is, however, computationally expensive and a significant bottleneck for self-consistent radiation transport codes treating the heating of dust by stars. In this paper, we summarize the formalism for computing the stochastic emissivity of cosmic dust, which was developed in earlier works, and present a new library HEATCODE implementing this formalism for the calculation for arbitrary grain properties and heating radiation fields. Our library is highly optimized for general-purpose processors with multiple cores and vector instructions, with hierarchical memory cache structure. The HEATCODE library also efficiently runs on co-processo...
Ahlstrom, D
2002-01-01
Prof Werner Nahm, of the School of Theoretical Physics, last night delivered talk at the Dublin Institute for Advanced Studies entitled, 'Hidden Dimensions'. It was one of a series offered by the Institute as part of Science Week Ireland (1 page).
Cohen, Adam B.
2009-01-01
Psychologists interested in culture have focused primarily on East-West differences in individualism-collectivism, or independent-interdependent self-construal. As important as this dimension is, there are many other forms of culture with many dimensions of cultural variability. Selecting from among the many understudied cultures in psychology,…
Energy Technology Data Exchange (ETDEWEB)
Vilkas, M J; Ishikawa, Y; Trabert, E
2005-12-22
Many-Body Perturbation Theory (MBPT) has been employed to calculate with high wavelength accuracy the extreme ultraviolet (EUV) spectra of F-like to P-like Xe ions. They discuss the reliability of the new calculations using the example of EUV beam-foil spectra of Xe, in which n = 3, {Delta}n = 0 transitions of Na-, Mg-, Al-like, and Si-like ions have been found to dominate. A further comparison is made with spectra from an electron beam ion trap, that is, from a device with a very different (low density) excitation balance.
Moncrieff, David; Baker, David J.; Wilson, Stephen
1989-08-01
The efficient evaluation of the second-order expression in the many-body perturbation theory expansion for the correlation energy on vector processing and parallel processing computers is discussed. It is argued that the linked diagram theorem not only leads to the well known theoretical advantages of the many-body perturbation theory approach which allows the calculation of correlation energies for large (i.e. extended molecules or species containing heavy atoms) systems but also decouples the many-electron problem allowing efficient implementation on parallel processing machines. Furthermore, the computation associated with each of the resulting subproblems is very well suited to vector processing machines. Timing tests are reported for the CRAY 1 and CDC Cyber 205 vector processors, for a 1 processor implementation on the CRAY X-MP/48 and the ETA-10E, and for a 4 processor implementation on the Cray X-MP/48.
Yan, Kun
2007-04-01
In this paper, by discussing the basic hypotheses about the continuous orbit and discrete orbit in two research directions of the background medium theory for celestial body motion, the concrete equation forms and their summary of the theoretic frame of celestial body motion are introduced. Future more, by discussing the general form of Binet's equation of celestial body motion orbit and it's solution of the advance of the perihelion of planets, the relations and differences between the continuous orbit theory and Newton's gravitation theory and Einstein's general relativity are given. And by discussing the fractional-dimension expanded equation for the celestial body motion orbits, the concrete equations and the prophesy data of discrete orbit or stable orbits of celestial bodies which included the planets in the Solar system, satellites in the Uranian system, satellites in the Earth system and satellites obtaining the Moon obtaining from discrete orbit theory are given too. Especially, as the preliminary exploration and inference to the gravitation curve of celestial bodies in broadly range, the concept for the ideal black hole with trend to infinite in mass density difficult to be formed by gravitation only is explored. By discussing the position hypothesis of fractional-dimension derivative about general function and the formula form the hypothesis of fractional-dimension derivative about power function, the concrete equation formulas of fractional-dimension derivative, differential and integral are described distinctly further, and the difference between the fractional-dimension derivative and the fractional-order derivative are given too. Subsequently, the concrete forms of measure calculation equations of self-similar fractal obtaining by based on the definition of form in fractional-dimension calculus about general fractal measure are discussed again, and the differences with Hausdorff measure method or the covering method at present are given. By applying
Ab Initio Many-Body Calculations of n-3H, n-4He, p-{3,4}He, and n-10Be Scattering
Quaglioni, Sofia
2008-01-01
We develop a new ab initio many-body approach capable of describing simultaneously both bound and scattering states in light nuclei, by combining the resonating-group method with the use of realistic interactions, and a microscopic and consistent description of the nucleon clusters. This approach preserves translational symmetry and Pauli principle. We present phase shifts for neutron scattering on 3H, 4He and 10Be and proton scattering on {3,4}He, using realistic nucleon-nucleon potentials. Our A=4 scattering results are compared to earlier ab initio calculations. We demonstrate that a proper treatment of the coupling to the n-10Be continuum is essential to explain the parity-inverted ground state in 11Be.
Energy Technology Data Exchange (ETDEWEB)
Zapukhlyak, Myroslav
2008-12-05
The present thesis gives a theoretical contribution to the understanding of the many-particle dynamics in inelastic ion-atom collisions. Many-electron dynamics in ion-helium collisions and proton-sodium collisions was theoretically studied. The description is based on the semiclassical approximation with the straight orbit for the projectile motion. The ion-atom collision problem is by this reduced to a time-dependent many-electron problem and in the non-relativistic approximation described by the time-dependent Schroedinger equation. The solution of the many-electron problem pursues in the framework of the time-dependent density functional theory. The time-dependent Schroedinger equation for the interacting many-electron problem is transformed to the system of the time-dependent Kohn-Sham equations and solved by the two-center-basis generator method. The unknown time-dependent exchange-correlation one-particle potential forces different approximation in the time-dependent Kohn-Shan scheme. In this thesis the model of the independent electrons was applied as basis model, in which the electron-electron correlation is consistently neglected in all parts and in all steps. Differential cross sections for different one- and two-electron processes were calculated in the so-called eikonal approximation for the collisional systems p-He, He{sup 2+}-He, and Ar{sup q+}-He (q=15-18). [German] Die vorliegende Arbeit leistet einen theoretischen Beitrag zum Verstaendnis der Vielteilchendynamik in inelastischen Ion-Atom-Stoessen. Vielelektronendynamik in Ion-Helium-Stoessen und Proton-Natrium-Stoessen wurde theoretisch untersucht. Die Beschreibung basiert auf der semiklassischen Naeherung mit der geraden Bahn fuer die Projektilbewegung. Das Ion-Atom- Stossproblem wird damit auf ein zeitabhaengiges Vielelektronenproblem reduziert und in der nichtrelativistischen Naeherung mit der zeitabhaengigen Schroedinger-Gleichung beschrieben. Die Loesung des Vielelektronenproblems erfolgt im
Jiang, Wei; Luo, Yun; Maragliano, Luca; Roux, Benoît
2012-11-13
An extremely scalable computational strategy is described for calculations of the potential of mean force (PMF) in multidimensions on massively distributed supercomputers. The approach involves coupling thousands of umbrella sampling (US) simulation windows distributed to cover the space of order parameters with a Hamiltonian molecular dynamics replica-exchange (H-REMD) algorithm to enhance the sampling of each simulation. In the present application, US/H-REMD is carried out in a two-dimensional (2D) space and exchanges are attempted alternatively along the two axes corresponding to the two order parameters. The US/H-REMD strategy is implemented on the basis of parallel/parallel multiple copy protocol at the MPI level, and therefore can fully exploit computing power of large-scale supercomputers. Here the novel technique is illustrated using the leadership supercomputer IBM Blue Gene/P with an application to a typical biomolecular calculation of general interest, namely the binding of calcium ions to the small protein Calbindin D9k. The free energy landscape associated with two order parameters, the distance between the ion and its binding pocket and the root-mean-square deviation (rmsd) of the binding pocket relative the crystal structure, was calculated using the US/H-REMD method. The results are then used to estimate the absolute binding free energy of calcium ion to Calbindin D9k. The tests demonstrate that the 2D US/H-REMD scheme greatly accelerates the configurational sampling of the binding pocket, thereby improving the convergence of the potential of mean force calculation.
Jiang, Wei; Luo, Yun; Maragliano, Luca; Roux, Benoît
2012-11-13
An extremely scalable computational strategy is described for calculations of the potential of mean force (PMF) in multidimensions on massively distributed supercomputers. The approach involves coupling thousands of umbrella sampling (US) simulation windows distributed to cover the space of order parameters with a Hamiltonian molecular dynamics replica-exchange (H-REMD) algorithm to enhance the sampling of each simulation. In the present application, US/H-REMD is carried out in a two-dimensional (2D) space and exchanges are attempted alternatively along the two axes corresponding to the two order parameters. The US/H-REMD strategy is implemented on the basis of parallel/parallel multiple copy protocol at the MPI level, and therefore can fully exploit computing power of large-scale supercomputers. Here the novel technique is illustrated using the leadership supercomputer IBM Blue Gene/P with an application to a typical biomolecular calculation of general interest, namely the binding of calcium ions to the small protein Calbindin D9k. The free energy landscape associated with two order parameters, the distance between the ion and its binding pocket and the root-mean-square deviation (rmsd) of the binding pocket relative the crystal structure, was calculated using the US/H-REMD method. The results are then used to estimate the absolute binding free energy of calcium ion to Calbindin D9k. The tests demonstrate that the 2D US/H-REMD scheme greatly accelerates the configurational sampling of the binding pocket, thereby improving the convergence of the potential of mean force calculation. PMID:26605623
Wang, Bing; Shen, Hao; Fang, Aiqin; Huang, De-Shuang; Jiang, Changjun; Zhang, Jun; Chen, Peng
2016-06-17
Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GC×GC/TOF-MS) system has become a key analytical technology in high-throughput analysis. Retention index has been approved to be helpful for compound identification in one-dimensional gas chromatography, which is also true for two-dimensional gas chromatography. In this work, a novel regression model was proposed for calculating the second dimension retention index of target components where n-alkanes were used as reference compounds. This model was developed to depict the relationship among adjusted second dimension retention time, temperature of the second dimension column and carbon number of n-alkanes by an exponential nonlinear function with only five parameters. Three different criteria were introduced to find the optimal values of parameters. The performance of this model was evaluated using experimental data of n-alkanes (C7-C31) at 24 temperatures which can cover all 0-6s adjusted retention time area. The experimental results show that the mean relative error between predicted adjusted retention time and experimental data of n-alkanes was only 2%. Furthermore, our proposed model demonstrates a good extrapolation capability for predicting adjusted retention time of target compounds which located out of the range of the reference compounds in the second dimension adjusted retention time space. Our work shows the deviation was less than 9 retention index units (iu) while the number of alkanes were added up to 5. The performance of our proposed model has also been demonstrated by analyzing a mixture of compounds in temperature programmed experiments. PMID:27208985
Engel, D.; Klews, M.; Wunner, G.
2009-02-01
and to provide a program which allows users to calculate as comprehensively as possible energies, wavelengths, and oscillator strengths of medium-Z atoms and ions up to Z=26 in neutron star magnetic field strengths. Obviously, the method for achieving this goal must be highly efficient since for the calculation of synthetic spectra data of many thousands or even millions of atomic transitions may be required. Solution method: As in previous work on the problem (cf. [3,7]) we exploit the fact that a strong magnetic field results in an approximate decoupling of the dynamics of the electrons parallel and perpendicular to the field. In this adiabatic approximation the single-particle wave functions take the form: ψ(ρ,φ,z)=ϕ(ρ,φ)ṡP(z), where ϕ(ρ,φ) are Landau wave functions, describing the (fast) motion perpendicular to the field, and the P(z) are the longitudinal wave functions, describing the (slow) bound motion along the direction of the field. The spins of the electrons are all aligned antiparallel to the magnetic field and need not be accounted for explicitly. The total N-electron wave function is constructed as a Slater determinant of the single-particle wave functions, and the unknown longitudinal wave functions are determined from the Hartree-Fock equations, which follow from inserting the total N-electron wave function into Schrödinger's variational principle for the total energy. The novel feature of our approach [8] is to use finite-element and B-spline techniques to solve the Hartree-Fock equations for atoms in strong magnetic fields. This is accomplished through the following steps: 1) decomposition of the z-axis into finite elements with quadratically widening element borders; 2) sixth-order B-spline expansion of the single-particle wave functions on the individual finite elements; 3) formulation of the variational principle equivalent to the Hartree-Fock equations in terms of the expansion coefficients. This leads to a simple system of linear
Safronova, M S; Derevianko, S A
1999-01-01
Removal energies and hyperfine constants of the lowest four $ns, np_{1/2}$ and $np_{3/2}$ states in Na, K, Rb and Cs are calculated; removal energies of the n=7--10 states and hyperfine constants of the n=7 and 8 states in Fr are also calculated. The calculations are based on the relativistic single-double (SD) approximation in which single and double excitations of Dirac-Hartree-Fock (DHF) wave functions are included to all-orders in perturbation theory. Using SD wave functions, accurate values of removal energies, electric-dipole matrix elements and static polarizabilities are obtained, however, SD wave functions give poor values of magnetic-dipole hyperfine constants for heavy atoms. To obtain accurate values of hyperfine constants for heavy atoms, we include triple excitations partially in the wave functions. The present calculations provide the basis for reevaluating PNC amplitudes in Cs and Fr.
Koch, D; Paulus, B
2016-01-01
Low-dimensional beryllium systems constitute interesting case studies for the test of correlation methods because of the importance of both static and dynamical correlation in the formation of the bond. Aiming to describe the whole dissociation curve of extended Be systems we chose to apply the method of increments (MoI) in its multireference (MR) formalism. However, in order to do so an insight into the wave function was necessary. Therefore we started by focusing on the description of small Be chains via standard quantum chemical methods and gave a brief analysis of the main characteristics of their wave functions. We then applied the MoI to larger beryllium systems, starting from the Be6 ring. First, the complete active space formalism (CAS-MoI) was employed and the results were used as reference for local MR calculations of the whole dissociation curve. Despite this approach is well established for the calculation of systems with limited multireference character, its application to the description of whol...
DEFF Research Database (Denmark)
Martinez, Jose Ignacio; García Lastra, Juan Maria; Lopez, M. J.;
2010-01-01
The optical spectra of sandwich clusters formed by transition metal atoms (titanium, vanadium, and chromium) intercalated between parallel benzene molecules have been studied by time-dependent density functional theory (TDDFT) and many-body perturbation theory. Sandwiches with different number...... the optical properties according to specific functionality targets. The differences in the spectra could be used to identify relative abundances of isomers with different spins in experimental studies. As a salient feature, this theoretical spectroscopic analysis predicts the metallization of the infinite (Ti...
Dimension of chaotic attractors
Energy Technology Data Exchange (ETDEWEB)
Farmer, J.D.; Ott, E.; Yorke, J.A.
1982-09-01
Dimension is perhaps the most basic property of an attractor. In this paper we discuss a variety of different definitions of dimension, compute their values for a typical example, and review previous work on the dimension of chaotic attractors. The relevant definitions of dimension are of two general types, those that depend only on metric properties, and those that depend on probabilistic properties (that is, they depend on the frequency with which a typical trajectory visits different regions of the attractor). Both our example and the previous work that we review support the conclusion that all of the probabilistic dimensions take on the same value, which we call the dimension of the natural measure, and all of the metric dimensions take on a common value, which we call the fractal dimension. Furthermore, the dimension of the natural measure is typically equal to the Lyapunov dimension, which is defined in terms of Lyapunov numbers, and thus is usually far easier to calculate than any other definition. Because it is computable and more physically relevant, we feel that the dimension of the natural measure is more important than the fractal dimension.
International Nuclear Information System (INIS)
Reduced matrix elements, oscillator strengths, and transition rates are calculated for all allowed and forbidden 2s-2p electric dipole transitions in berylliumlike ions with nuclear charges ranging from Z = 4 to 100. Many-body perturbation theory (MBPT), including the Breit interaction, is used to evaluate retarded E1 matrix elements in length and velocity forms. The calculations start with a 1s2 Dirac-Fock potential and include all possible n = 2 configurations, leading to 4 odd-parity and 6 even-parity states. First-order perturbation theory is used to obtain intermediate coupling coefficients. Second-order MBPT is used to determine the matrix elements, which are evaluated for the 16 possible E1 transitions. The transition energies used in the calculation of oscillator strengths and transition rates are evaluated using second-order MBPT. The importance of virtual electron-positron pair (negative energy) contributions to the transition amplitudes is discussed. (orig.)
Wang, Kai; Si, Ran; Jönsson, Per; Ekman, Jörgen; Guo, Xue Lin; Li, Shuang; Long, Fei Yun; Dang, Wei; Zhao, Xiao Hui; Hutton, Roger; Chen, Chong Yang; Yan, Jan; Yang, Xu
2016-01-01
Level energies, wavelengths, electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition rates, oscillator strengths, and line strengths from combined relativistic configuration interaction and many-body perturbation calculations are reported for the 201 fine-structure states of the $2s^2 2p^6$, $2s^2 2p^5 3l$, $2s 2p^6 3l$, $2s^2 2p^5 4l$, $2s 2p^6 4l$, $2s^2 2p^5 5l$, and $2s^2 2p^5 6l$ configurations in all Ne-like ions between Cr XV and Kr XXVII. Calculated level energies and transition data are compared with experiments from the NIST and CHIANTI databases, and other recent benchmark calculations. The mean energy difference with the NIST experiments is only 0.05%. The present calculations significantly increase the amount of accurate spectroscopic data for the $n >3$ states in a number of Ne-like ions of astrophysics interest. A complete dataset should be helpful in analyzing new observations from the solar and other astrophysical sources, and is also likely to be useful for ...
Wang, K.; Chen, Z. B.; Si, R.; Jönsson, P.; Ekman, J.; Guo, X. L.; Li, S.; Long, F. Y.; Dang, W.; Zhao, X. H.; Hutton, R.; Chen, C. Y.; Yan, J.; Yang, X.
2016-10-01
Level energies, wavelengths, electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition rates, oscillator strengths, and line strengths from combined relativistic configuration interaction and many-body perturbation calculations are reported for the 201 fine-structure states of the 2{s}22{p}6, 2{s}22{p}53l, 2s2{p}63l, 2{s}22{p}54l, 2s2{p}64l, 2{s}22{p}55l, and 2{s}22{p}56l configurations in all Ne-like ions between Cr xv and Kr xxvii. Calculated level energies and transition data are compared with experiments from the National Institute of Standards and Technology (NIST) and CHIANTI databases, and other recent benchmark calculations. The mean energy difference with the NIST experiments is only 0.05%. The present calculations significantly increase the amount of accurate spectroscopic data for the n > 3 states in a number of Ne-like ions of astrophysical interest. A complete data set should be helpful for analyzing new observations from solar and other astrophysical sources, and is also likely to be useful for modeling and diagnosing a variety of plasmas, including astronomical and fusion plasma.
Energy Technology Data Exchange (ETDEWEB)
Safronova, U I; Safronova, A S; Beiersdorfer, P
2007-01-05
Transition rates, oscillator strengths, and line strengths are calculated for electric-dipole (E1) transitions between odd-parity 3s{sup 2}3p{sup 6}3d{sup 9}4{ell}{sub 2}, 3s{sup 2}3p{sup 5}3d{sup 10}4{ell}{sub 2}, and 3s3p{sup 6}3d{sup 10}4{ell}{sub 1} states and even-parity 3s{sup 2}3p{sup 6}3d{sup 9}4{ell}{sub 2}, 3s{sup 2}3p{sup 5}3d{sup 10}4{ell}{sub 1}, and 3s3p{sup 6}3d{sup 10}4{ell}{sub 2} (with 4{ell}{sub 1} = 4p; 4f and 4{ell}{sub 2} = 4s; 4d) in Ni-like ions with the nuclear charges ranging from Z = 34 to 100. Relativistic many-body perturbation theory (RMBPT), including the Breit interaction, is used to evaluate retarded E1 matrix elements in length and velocity forms. The calculations start from a 1s{sup 2}2s{sup 2}2p{sup 6}3s{sup 2}3p{sup 6}3d{sup 10} Dirac-Fock potential. First-order RMBPT is used to obtain intermediate coupling coefficients and second-order RMBPT is used to calculate transition matrix elements. Contributions from negative-energy states are included in the second-order E1 matrix elements to ensure the gauge independence of transition amplitudes. Transition energies used in the calculation of oscillator strengths and transition rates are from second-order RMBPT. Lifetimes of the 3s{sup 2}3p{sup 6}3d{sup 9}4d levels are given for Z = 34-100. Transition rates, line strengths, and oscillator strengths are compared with critically evaluated experimental values and with results from other recent calculations. These atomic data are important in modeling of M-shell radiation spectra of heavy ions generated in electron beam ion trap experiments and in M-shell diagnostics of plasmas.
中性碳原子基态关联效应的多体理论计算%Many-body calculation on the ground state correlation effects of neutral Carbon
Institute of Scientific and Technical Information of China (English)
唐利强; 易有根; 袁建民; 高永毅; 周并举
2001-01-01
应用原子多体理论对开壳层原子中电子关联效应的有效哈密顿量及波算符的Goldston图进行了分析，在此基础上得到了计算有效哈密顿量的简单方法；以HFS模型为零级近似对中性碳原子基态的关联效应进行了计算并通过与实验结果及其他文献基于HF模型进行的计算相比较，得到了令人满意的结论。%Applying atomic many-body theory to analyse the Goldston diagrams of effective Hamiltonian and wave operator about electron-electron correlation for open shell atoms, we use a simple method to evaluate the effective Hamiltonian and calculate the correlation effectes of Corbon with HFS model as a zeroth order approximation. Making contrasts with the experiment and the calculation based on HF model we get pleased results.
Calculation Method Analysis of Many Roulette Rotor System Critical Speed%多轮盘转子系统临界转速的计算方法分析
Institute of Scientific and Technical Information of China (English)
冀成; 杨兆建; 宋高峰; 庞新宇
2012-01-01
In order to ensure the stability of the many roulette rotor system,for the determination of the rotor system critical speed,DengKe lai method was adopted ,and using matrix method and the finite element method to calculate based on ANSYS respectively for the critical speed, and the results were compared and analyzed.The results show that the three methods are of different range,in which the limited element method based on ANSYS is in high accuracy,with simple calculation, providing for other engineering of the rotor system solution of the critical speed a reliable basis.%为了保障多轮盘转子系统的稳定性,针对多轮盘转子临界转速的确定问题,分别采用了邓柯莱法,传递矩阵法和基于ANSYS的有限元法进行求解,并对所得结果进行了分析和比较.结果表明三种方法的适用范围不同,其中基于ANSYS的限元法对转子系统的临界转速的求解准确度高,计算简便,为工程上其它转子系统的临界转速的求解提供了可靠的依据.
罐车罐体的容积精确计算与尺寸反求方法研究%Method of capacity accurate calculation and dimension reverse of tank body
Institute of Scientific and Technical Information of China (English)
姚都; 常智勇; 莫蓉; 窦杨柳
2012-01-01
为计算罐车罐体的容积和在已知容积的情况下确定罐体的设计尺寸,基于UG NX软件的内空间分析器(Space Finder)以及实体体积计算和优化功能,提出了两种罐体容积计算和尺寸反求方法.一种快捷的方法是利用Space Finder 计算容积,并在此基础上对设计尺寸进行反求计算；另一种精确的方法是利用关联性复制,将装配环境中的模型保持装配关系转换到零件环境中,运用布尔运算和抽取面以及修剪体,得到罐体内空间的实体表示,然后利用实体体积计算功能得到罐体的容积,再利用实体优化功能,在得到内空间实体表示的基础上,根据给定的容积迭代反求出设计尺寸.通过UG/Open二次开发,编写出专用工具.最后,通过对某型号罐车罐体的容积计算与尺寸反求,对该方法进行验证,证明该方法的准确性和有效性.%To calculate the tank body' s capacity and determine the design dimensions of the tank body given the capacity,two tank body' s capacity calculation and dimension reverse methods were proposed based on the NX Space Finder and the entity volume calculation and optimization function. An efficient method is using Space Finder to calculate the capacity and design the dimension reverse algorithm based on it. The other accurate method is using relevance duplication to transform models from assembly environment to part environment based on keeping the assembly relationship. Get the entity representation of tank body's inner space through using of Boolean operation,extraction surfaces and trim body. Then use the entity volume calculation function to get capacity of the tank body. Use the entity optimization function to obtain design dimensions according to the given capacity on die basis of getting the entity representation of inner space. Write special tools through the LG/Open second development. Finally , a case study of volume calculation and dimension reverse of a certain tank
Institute of Scientific and Technical Information of China (English)
李益海
2013-01-01
At present,the newly built large mines and the most of reorganization and expansion mines use many airshaft unit ventilation.In many airshaft production mine,the number of working face in each mining area along with the change of yield continuously increase and decrease,correspondingly air volume of each mining area must rede-ploy,the working point of each airshaft main fan also must change.However,the main blades angle how adjustment can make the mining area reach scheduled air volume and resistance,it is a subject urgently to be solved in current. Through the example,using mathematical analytical method in a short period of time to calculate reasonably accurate results,so as to find out the exact main fan blade angle,reasonably allot the air volume of the mining area.Thus a-void using artificial test the fan blade angle or other method,cannot accurately calculate,caused air waste or insuffi-cient air flow phenomenon,make the mine ventilation achieve science and reasonable.% 目前，新建的大型矿井和改扩建矿井多数采用多风井分区通风。在多风井生产矿井中，各采区采掘工作面数量随着产量的变化不断增减，相应各采区的风量就必须重新进行调配，致使各风井主扇的工况点也必须改变。然而，各主扇叶角调转多少度数才能使各采区达到预定的风量和阻力，这是当前亟待解决的一个课题。通过实例，运用数学解析法可在短时间内计算得出准确合理的结果，从而找到准确的主扇风叶角度，做到各采区风量的合理分配。从而避免采取人工试调风机叶角或其它方法无法准确解算造成的风量浪费或风量不足的现象，使矿井通风科学合理。
Directory of Open Access Journals (Sweden)
L Otero Pereiro
1998-01-01
.____________________________________________________________________AbstractThe Finite Elements Method (FEM developed until the present time is a powerful computerized calculation system applied inthe tensions and deformations analysis of solids and structures and much literature has been published on FEM as calculationmethod,The need of solving the problems of passengers transportation, mainly in Havana City, in the difficult conditions of Cubanspecial period, conducted to the development of a semi - trailer with the necessary characteristics to fulfil this function , whichby their attributes constitutes the only one in his gender for this purpose.It is, the first time that in our country is executed the calculation of a self - potable reticulated structure of similar magnitude,with satisfactory concrete results.It is approached the creation of a physic - mathematical model that simulates the real structure, conditioned to the limitations ofthe calculation program, offering a similar behavior in the efforts and deformations that are produced, with a study of thedifferent variants of results.In the work are obtained some results on the possible consequences the calculation of the complete structure or separating it bysections, being necessary the establishment of a methodical for the definition of those sections that they can be analyzedseparately, as well as the order of importance of this analysis.It was accomplished the experimental determination of the dynamic load coefficient, as well as the establishment of the physic- mathematical model adapted for the calculation of the structure of a semi - trailer for passengers transportation applying theFinite Elements Method.It was effected a test to statics load del frame to corroborate the validity of the physic - mathematical model of the structure.Additionally, It is proposed a technical solution within the technological possibilities of the constructing company to avoid thestructure breakage of the equipment.
The Hausdorff Dimension of Sections
Institute of Scientific and Technical Information of China (English)
Min NIU; Lifeng XI
2007-01-01
The notion of finite-type open set condition is defined to calculate the Hausdorff dimensions of the sections of some self-similar sets, such as the dimension of intersection of the Koch curve and the line x = a with a ∈(Q).
Fractal Dimension for Fractal Structures
Fernández-Martínez, M.; Sánchez-Granero, M. A.
2010-01-01
The main goal of this paper has a double purpose. On the one hand, we propose a new definition in order to compute the fractal dimension of a subset respect to any fractal structure, which completes the theory of classical box-counting dimension. Indeed, if we select the so called natural fractal structure on each euclidean space, then we will get the box-counting dimension as a particular case. Recall that box-counting dimension could be calculated over any euclidean space, although it can b...
Institute of Scientific and Technical Information of China (English)
刘燕德; 蒋育华; 欧阳爱国
2001-01-01
Space and place errors affecting assembling precision were discussed by calcutating the clearance of cylinder.This paper points out the calculating way of assembling dimension chain including space and space errors. The increasing clearance of hole and axis is also concluded.%通过计算光滑圆柱体的配合间隙,分析了形位公差对加工装配精度的影响,给出包括形位公差在内的有关装配尺寸链的解法,并得出考虑形位误差在内孔轴配合间隙变大的结论。
Entanglement and double occupancy in many-electron states
Energy Technology Data Exchange (ETDEWEB)
Subrahmanyam, V., E-mail: vmani@iitk.ac.i [Department of Physics, Indian Institute of Technology, Kanpur 208016 (India)
2010-07-12
The entanglement in many-electron states is investigated using a global entanglement measure, viz. average site mixedness. We have examined metallic states of noninteracting electrons, Nagaoka and Gutzwiller states of strongly-correlated electrons, and superconducting states. Uncorrelated metallic states at half filling seem to maximize entanglement, as these states optimize the number of holes, the number of doubly-occupied sites. Entanglement is calculated explicitly for Gutzwiller-projected many-electron states in one dimension, which have less entanglement as double occupancy is inhibited in these states. Entanglement in superconducting states, which tend to promote double occupancy, is calculated as a function of the energy gap, and found to be lower than the metallic state entanglement. There is a possibility of a regime with a nonzero single-site concurrence depending on the energy gap.
Energy Technology Data Exchange (ETDEWEB)
Changala, P. Bryan, E-mail: bryan.changala@colorado.edu; Baraban, Joshua H.; Field, Robert W. [Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Stanton, John F. [Department of Chemistry and Biochemistry, Institute for Theoretical Chemistry, The University of Texas at Austin, Austin, Texas 78712 (United States); Merer, Anthony J. [Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan and Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1 (Canada)
2014-01-14
Reduced dimension variational calculations have been performed for the rovibrational level structure of the S{sub 1} state of acetylene. The state exhibits an unusually complicated level structure, for various reasons. First, the potential energy surface has two accessible conformers, trans and cis. The cis conformer lies about 2700 cm{sup −1} above the trans, and the barrier to cis-trans isomerization lies about 5000 cm{sup −1} above the trans minimum. The trans vibrations ν{sub 4} (torsion) and ν{sub 6} (asym. bend) interact very strongly by Darling-Dennison and Coriolis resonances, such that their combination levels and overtones form polyads with unexpected structures. Both conformers exhibit very large x{sub 36} cross-anharmonicity since the pathway to isomerization is a combination of ν{sub 6} and ν{sub 3} (sym. bend). Near the isomerization barrier, the vibrational levels show an even-odd K-staggering of their rotational levels as a result of quantum mechanical tunneling through the barrier. The present calculations address all of these complications, and reproduce the observed K-structures of the bending and C–C stretching levels with good qualitative accuracy. It is expected that they will assist with the assignment of the irregular patterns near the isomerization barrier.
Classical equation of motion and anomalous dimensions at leading order
Nii, Keita
2016-07-01
Motivated by a recent paper by Rychkov-Tan [1], we calculate the anomalous dimensions of the composite operators at the leading order in various models including a ϕ 3-theory in (6 - ɛ) dimensions. The method presented here relies only on the classical equation of motion and the conformal symmetry. In case that only the leading expressions of the critical exponents are of interest, it is sufficient to reduce the multiplet recombination discussed in [1] to the classical equation of motion. We claim that in many cases the use of the classical equations of motion and the CFT constraint on two- and three-point functions completely determine the leading behavior of the anomalous dimensions at the Wilson-Fisher fixed point without any input of the Feynman diagrammatic calculation. The method developed here is closely related to the one presented in [1] but based on a more perturbative point of view.
2013-01-01
A few weeks ago, I had a vague notion of what TED was, and how it worked, but now I’m a confirmed fan. It was my privilege to host CERN’s first TEDx event last Friday, and I can honestly say that I can’t remember a time when I was exposed to so much brilliance in such a short time. TEDxCERN was designed to give a platform to science. That’s why we called it Multiplying Dimensions – a nod towards the work we do here, while pointing to the broader importance of science in society. We had talks ranging from the most subtle pondering on the nature of consciousness to an eighteen year old researcher urging us to be patient, and to learn from our mistakes. We had musical interludes that included encounters between the choirs of local schools and will.i.am, between an Israeli pianist and an Iranian percussionist, and between Grand Opera and high humour. And although I opened the event by announcing it as a day off from physics, we had a quite brill...
Aarts, JM
1993-01-01
Two types of seemingly unrelated extension problems are discussed in this book. Their common focus is a long-standing problem of Johannes de Groot, the main conjecture of which was recently resolved. As is true of many important conjectures, a wide range of mathematical investigations had developed, which have been grouped into the two extension problems. The first concerns the extending of spaces, the second concerns extending the theory of dimension by replacing the empty space with other spaces. The problem of de Groot concerned compactifications of spaces by means of an adjunction of a set of minimal dimension. This minimal dimension was called the compactness deficiency of a space. Early success in 1942 lead de Groot to invent a generalization of the dimension function, called the compactness degree of a space, with the hope that this function would internally characterize the compactness deficiency which is a topological invariant of a space that is externally defined by means of compact extensions of a...
DEFF Research Database (Denmark)
Rasmussen, Filip Anselm; Schmidt, Per Simmendefeldt; Winther, Kirsten Trøstrup;
2016-01-01
Calculating the quasiparticle (QP) band structure of two-dimensional (2D) materials within the GW self-energy approximation has proven to be a rather demanding computational task. The main reason is the strong q dependence of the 2D dielectric function around q = 0 that calls for a much denser...
Higuchi dimension of digital images.
Directory of Open Access Journals (Sweden)
Helmut Ahammer
Full Text Available There exist several methods for calculating the fractal dimension of objects represented as 2D digital images. For example, Box counting, Minkowski dilation or Fourier analysis can be employed. However, there appear to be some limitations. It is not possible to calculate only the fractal dimension of an irregular region of interest in an image or to perform the calculations in a particular direction along a line on an arbitrary angle through the image. The calculations must be made for the whole image. In this paper, a new method to overcome these limitations is proposed. 2D images are appropriately prepared in order to apply 1D signal analyses, originally developed to investigate nonlinear time series. The Higuchi dimension of these 1D signals is calculated using Higuchi's algorithm, and it is shown that both regions of interests and directional dependencies can be evaluated independently of the whole picture. A thorough validation of the proposed technique and a comparison of the new method to the Fourier dimension, a common two dimensional method for digital images, are given. The main result is that Higuchi's algorithm allows a direction dependent as well as direction independent analysis. Actual values for the fractal dimensions are reliable and an effective treatment of regions of interests is possible. Moreover, the proposed method is not restricted to Higuchi's algorithm, as any 1D method of analysis, can be applied.
Measuring border irregularities of skin lesions using fractal dimensions
Ng, Vincent T. Y.; Lee, Tim K.
1996-09-01
Malignant melanoma is the most common cancer in people less than 35 years of age and incident rates are increasing by approximately 5 percent per annum in many white populations, including British Columbia, Canada. In 1994, a clinical study has been established to digitize melanocytic lesions under a controlled environment. Lesions are digitized from patients who are referred to the Colored Pigment Lesion Clinic in the University of British Columbia. In this paper, we investigate how to use fractal dimensions (FDs) in measuring the irregularity of a skin lesion. In a previous project, we have experimented with 6 different methods to calculate fractal dimensions on a small number of images of skin lesions, and the simple box-counting method performed the best. However, the method did not exploit the intensity information of the images. With the new set of images which are digitized under the controlled environment, we utilize the differential box counting method to exploit such information. Four FD measures, including the direct FD, the horizontal and the vertical smoothing FDs, and the multi- fractal dimension of order two, are calculated based on the original color images. In addition, these 4 FD features are repeatedly calculate for the blue band of the images. This paper reports the different features through the calculations of the fractal dimensions and compares their differentiation power in the use of diagnosis of images of skin lesions.
Bolc, Leonard
1992-01-01
Many-valued logics were developed as an attempt to handle philosophical doubts about the "law of excluded middle" in classical logic. The first many-valued formal systems were developed by J. Lukasiewicz in Poland and E.Post in the U.S.A. in the 1920s, and since then the field has expanded dramatically as the applicability of the systems to other philosophical and semantic problems was recognized. Intuitionisticlogic, for example, arose from deep problems in the foundations of mathematics. Fuzzy logics, approximation logics, and probability logics all address questions that classical logic alone cannot answer. All these interpretations of many-valued calculi motivate specific formal systems thatallow detailed mathematical treatment. In this volume, the authors are concerned with finite-valued logics, and especially with three-valued logical calculi. Matrix constructions, axiomatizations of propositional and predicate calculi, syntax, semantic structures, and methodology are discussed. Separate chapters deal w...
Rip, Arie; Groen, Aard J.; Coombs, R.; Green, K.; Richards, A.; Walsh, V.
2001-01-01
Compared with the ‘careless technology’ of the 1960s (to quote the title of a book at the time (Farvar and Milton, 1972)), the present safety, reliability and environmental friendliness of many products and technologies, at least in the richer countries, is striking. Salmon are swimming in the Thame
The Interpretation of Quantum Mechanics Many Worlds or Many Words?
Tegmark, M
1998-01-01
As cutting-edge experiments display ever more extreme forms of non-classical behavior, the prevailing view on the interpretation of quantum mechanics appears to be gradually changing. A (highly unscientific) poll taken at the 1997 UMBC quantum mechanics workshop gave the once all-dominant Copenhagen interpretation less than half of the votes. The Many Worlds interpretation (MWI) scored second, comfortably ahead of the Consistent Histories and Bohm interpretations. It is argued that since all the above-mentioned approaches to nonrelativistic quantum mechanics give identical cookbook prescriptions for how to calculate things in practice, practical-minded experimentalists, who have traditionally adopted the ``shut-up-and-calculate interpretation'', typically show little interest in whether cozy classical concepts are in fact real in some untestable metaphysical sense or merely the way we subjectively perceive a mathematically simpler world where the Schrodinger equation describes everything - and that they are t...
Trimble, Virginia L.
2016-06-01
For most of our early ancestors, the earth was the universe, with a blue bowl over it, good things above and evil things below, and exoplanets would have been multiverses. The steps beyond that included (1) many planets orbiting the sun, (2) the stars are suns, (3) most probably with their own planets, (4) the solar system is not central to the Milky Way, (5) other galaxies exist, and (6) many groups, clusters and superclusters (on a cosmic web). Famous names associated with these steps include Copernicus, Digges, Galileo, Newton, Shapley, Hubble, Sandage, and Peebles (plus many other less famous contributors). At every stage there have been mavens who said “one” and supermavens who have said “many”. So far, the latter have always won. I see no reason why this should not continue to be the case onward to one or more of the concepts now subsumed under the name multiverse. If we cannot think of a way to falsify the concepts, does this mean that they are not science? Or does it just mean that we have not yet thought of the right observations, in the way the lagging 17th century geocentrists did not anticipate Bradley’s aberration of starlight and Kapteyn did not have the chance to incorporate Shapley’s globular clusters in his universe? Some of the images shown will be more realistic than others.
On the selection of dimension reduction techniques for scientific applications
Energy Technology Data Exchange (ETDEWEB)
Fan, Y J; Kamath, C
2012-02-17
Many dimension reduction methods have been proposed to discover the intrinsic, lower dimensional structure of a high-dimensional dataset. However, determining critical features in datasets that consist of a large number of features is still a challenge. In this paper, through a series of carefully designed experiments on real-world datasets, we investigate the performance of different dimension reduction techniques, ranging from feature subset selection to methods that transform the features into a lower dimensional space. We also discuss methods that calculate the intrinsic dimensionality of a dataset in order to understand the reduced dimension. Using several evaluation strategies, we show how these different methods can provide useful insights into the data. These comparisons enable us to provide guidance to a user on the selection of a technique for their dataset.
Knowledge dimensions in hypothesis test problems
Krishnan, Saras; Idris, Noraini
2012-05-01
The reformation in statistics education over the past two decades has predominantly shifted the focus of statistical teaching and learning from procedural understanding to conceptual understanding. The emphasis of procedural understanding is on the formulas and calculation procedures. Meanwhile, conceptual understanding emphasizes students knowing why they are using a particular formula or executing a specific procedure. In addition, the Revised Bloom's Taxonomy offers a twodimensional framework to describe learning objectives comprising of the six revised cognition levels of original Bloom's taxonomy and four knowledge dimensions. Depending on the level of complexities, the four knowledge dimensions essentially distinguish basic understanding from the more connected understanding. This study identifiesthe factual, procedural and conceptual knowledgedimensions in hypothesis test problems. Hypothesis test being an important tool in making inferences about a population from sample informationis taught in many introductory statistics courses. However, researchers find that students in these courses still have difficulty in understanding the underlying concepts of hypothesis test. Past studies also show that even though students can perform the hypothesis testing procedure, they may not understand the rationale of executing these steps or know how to apply them in novel contexts. Besides knowing the procedural steps in conducting a hypothesis test, students must have fundamental statistical knowledge and deep understanding of the underlying inferential concepts such as sampling distribution and central limit theorem. By identifying the knowledge dimensions of hypothesis test problems in this study, suitable instructional and assessment strategies can be developed in future to enhance students' learning of hypothesis test as a valuable inferential tool.
Directory of Open Access Journals (Sweden)
Milica Antić Gaber
2013-12-01
We believe that in the present thematic issue we have succeeded in capturing an important part of the modern European research dynamic in the field of migration. In addition to well-known scholars in this field several young authors at the beginning their research careers have been shortlisted for the publication. We are glad of their success as it bodes a vibrancy of this research area in the future. At the same time, we were pleased to receive responses to the invitation from representatives of so many disciplines, and that the number of papers received significantly exceeded the maximum volume of the journal. Recognising and understanding of the many faces of migration are important steps towards the comprehensive knowledge needed to successfully meet the challenges of migration issues today and even more so in the future. It is therefore of utmost importance that researchers find ways of transferring their academic knowledge into practice – to all levels of education, the media, the wider public and, of course, the decision makers in local, national and international institutions. The call also applies to all authors in this issue of the journal.
DEFF Research Database (Denmark)
Buhl, Mie; Meyer, Bente Tobiesen
2014-01-01
builds on data from two research projects that investigated the iPad as a learning device in the context of primary and lower secondary schooling in Denmark. In these projects learning with the iPad focused on 1) the role of the iPad in inclusive learning environments 2) children’s visual cultures......Pad may expose the diversity of artifacts that are already present as actors in learning contexts. As one among many artefacts used in orchestrating learning, the iPad acts in shifting material cultures of schooling where for instance pens, paper, books or interactive whiteboards are used in combination...... the integration of a mobile learning device into education. In this paper we shall discuss how the iPad becomes an actor in socio-material contexts of schooling and how it becomes significant for learning as an artifact with specific affordances within these contexts. We argue that the implementation of the i...
Antonella Del Rosso
2013-01-01
How many Higgs bosons are out there? Several theoretical models foresee the existence of more than one such boson but the current data cannot confirm any of these scenarios. What should we expect from the future data and the results of the current analysis? Image: Xavier Cortada (with the participation of physicist Pete Markowitz), "In search of the Higgs boson: H -> ZZ", digital art, 2013. Please note that this image is a detail from Xavier Cortada's art work installed at LHC P5 CMS. According to some theories, the mechanism that requires the existence of the Higgs boson (known by physicists as “electroweak symmetry breaking”) could also imply the involvement of other spin-zero – “boson” – particles. How would these relate to the newly-discovered particle? “The properties that the other Higgs bosons would have vary a lot depending on the theoretical model you consider,” explain...
Energy Technology Data Exchange (ETDEWEB)
Rivasseau, Vincent [Paris-Sud Univ. Orsay (France). Laboratoire de Physique Theorique; Seiringer, Robert [McGill Univ., Montreal, QC (Canada). Dept. of Mathematics and Statistics; Solovej, Jan Philip [Copenhagen Univ. (Denmark). Dept. of Mathematics; Spencer, Thomas [Institute for Advanced Study, Princeton, NJ (United States). School of Mathematics
2012-11-01
The book is based on the lectures given at the CIME school ''Quantum many body systems'' held in the summer of 2010. It provides a tutorial introduction to recent advances in the mathematics of interacting systems, written by four leading experts in the field: V. Rivasseau illustrates the applications of constructive Quantum Field Theory to 2D interacting electrons and their relation to quantum gravity; R. Seiringer describes a proof of Bose-Einstein condensation in the Gross-Pitaevski limit and explains the effects of rotating traps and the emergence of lattices of quantized vortices; J.-P. Solovej gives an introduction to the theory of quantum Coulomb systems and to the functional analytic methods used to prove their thermodynamic stability; finally, T. Spencer explains the supersymmetric approach to Anderson localization and its relation to the theory of random matrices. All the lectures are characterized by their mathematical rigor combined with physical insights.
Application of General fractal Dimension to Coupling Fault Diagnosis
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
This paper presents the coucept of general and sensitive dimension, and also proposes the calculation formula of the general dimension least squares method. By calculating and analyzing the power spectrum and general dimension from the fault sample, the relationship is achieved between sample status and the general dimension from vibration signals function of general dimension is proposed, and calculations are carried out for a monitor signal and samples signal. The diagnosis method based on fractal theory is effective through the concrete examples of the steam-electric generating set fault diagnosis, and the correlation coefficient of general dimension between a monitor signal and samples signal can improve the accuracy for fault diagnosis.
DEFF Research Database (Denmark)
Buhl, Mie; Meyer, Bente Tobiesen
2014-01-01
that are already present as actors in learning contexts. As one among many artifacts used in orchestrating learning, the iPad acts in shifting material cultures of schooling where for instance pens, paper, books or interactive whiteboards are used in combination with the tablet. At other times the iPad itself acts...... that investigated the iPad as a learning device in the context of primary and lower secondary schooling in Denmark. In these projects learning with the iPad focused on 1) the role of the iPad in inclusive learning environments 2) children’s visual cultures and the development of the iBook iTAVS. Based......In this paper we shall discuss how the iPad becomes an actor in socio-material contexts of schooling and how it becomes significant for learning as an artifact with specific affordances within these contexts. We argue that the implementation of the iPad may expose the diversity of artifacts...
Form Invariant Sommerfeld Electrical Conductivity in Generalised d Dimensions
Institute of Scientific and Technical Information of China (English)
Muktish Acharyya
2011-01-01
The Sommerfeld electrical conductivity is calculated in d dimensions following Boltzmann kinetic approach. At T =0, the mathematical form of the electrical conductivity is found to remain invariant in any generalised spatial （d） dimensions.
Dimensioning aids in practice. A comparison
Energy Technology Data Exchange (ETDEWEB)
Weinreich, Bernhard; Zehner, Mike
2009-07-01
State-of-the art dimensioning programmes can calculate almost everything - but can you also access these functions intuitively? On behalf of S and WE, Bernhard Weinreich and Mike Zehner have tested the handling of the most common programmes. (orig.)
Fractal Dimension of Voice-Signal Waveforms
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
The fractal dimension is one important parameter that characterizes waveforms. In this paper, we derive a new method to calculate fractal dimension of digital voice-signal waveforms. We show that fractal dimension is an efficient tool for speaker recognition or speech recognition. It can be used to identify different speakers or distinguish speech. We apply our results to Chinese speaker recognition and numerical experiment shows that fractal dimension is an efficient parameter to characterize individual Chinese speakers. We have developed a semiautomatic voiceprint analysis system based on the theory of this paper and former researches.
The implication of fractal dimension in hydrogeology and rock mechanics. Version 1.1
International Nuclear Information System (INIS)
Since much of geology and hydrogeology is controlled by the geometry of geologic features such as faults, fractures and stratigraphy, many researchers have proposed the use of fractal dimension as an index for comparing hydrogeologic environments. This report describes an investigation carried out by Golder Associates Geosystem AB to evaluate the use of fractal measures within the SKB site selection, evaluation, and characterization process. This report defines fractal dimension and the methods available for calculating fractal dimension. The report then summarizes a literature survey carried out to identify and evaluate applications of fractal methods in hydrogeology. Preliminary hydrogeological fractal numerical simulations carried out with the FracMan package are then presented and discussed. These numerical simulations evaluate the application of fractal methods within the context of other geometric measures such as connectivity measures, percolation probability, and block size measures. Based upon the literature survey and numerical simulations, recommendations are presented regarding the potential usefulness of fractal approaches. Fractal dimension can be used to distinguish hydrogeologic environments, provided the limitations of the approach are explicitly recognized. Recommendations are made for fractal dimension calculation procedures, specification of fractal dimension, and the use of fractal dimension in conjunction with other measures of hydrogeologic structure and heterogeneity. (135 refs.) (au)
On Universal Quantum Dimensions
Mkrtchyan, R L
2016-01-01
We derive universal expressions for quantum dimensions (universal characters) of some series of irreps of simple Lie algebras. This allows us to check Deligne's hypothesis on universal quantum dimensions for symmetric cube of adjoint representation.
Strongly Gorenstein Flat Dimensions
Institute of Scientific and Technical Information of China (English)
Chun Xia ZHANG; Li Min WANG
2011-01-01
This article is concerned with the strongly Gorenstein flat dimensions of modules and rings.We show this dimension has nice properties when the ring is coherent,and extend the well-known Hilbert's syzygy theorem to the strongly Gorenstein flat dimensions of rings.Also,we investigate the strongly Gorenstein flat dimensions of direct products of rings and (almost)excellent extensions of rings.
Goparaju Purna SUDHAKAR
2013-01-01
Popularity of teams is growing in 21st Century. Organizations are getting their work done through different types of teams. Teams have proved that the collective performance is more than the sum of the individual performances. Thus, the teams have got different dimensions such as quantitative dimensions and qualitative dimensions. The Quantitative dimensions of teams such as team performance, team productivity, team innovation, team effectiveness, team efficiency, team decision making and tea...
Computability and Fractal Dimension
Reimann, Jan
2004-01-01
This thesis combines computability theory and various notions of fractal dimension, mainly Hausdorff dimension. An algorithmic approach to Hausdorff measures makes it possible to define the Hausdorff dimension of individual points instead of sets in a metric space. This idea was first realized by Lutz (2000). Working in the Cantor space of all infinite binary sequences, we study the theory of Hausdorff and other dimensions for individual sequences. After giving an overview over the classical...
Quantum Field Theory in (0 + 1) Dimensions
Boozer, A. D.
2007-01-01
We show that many of the key ideas of quantum field theory can be illustrated simply and straightforwardly by using toy models in (0 + 1) dimensions. Because quantum field theory in (0 + 1) dimensions is equivalent to quantum mechanics, these models allow us to use techniques from quantum mechanics to gain insight into quantum field theory. In…
Akama, Yohji; Irie, Kei
2011-01-01
We will establish that the VC dimension of the class of d-dimensional ellipsoids is (d^2+3d)/2, and that maximum likelihood estimate with N-component d-dimensional Gaussian mixture models induces a geometric class having VC dimension at least N(d^2+3d)/2. Keywords: VC dimension; finite dimensional ellipsoid; Gaussian mixture model
Spherical Harmonics in p Dimensions
Frye, Christopher; Efthimiou, Costas J.
2012-01-01
The authors prepared this booklet in order to make several useful topics from the theory of special functions, in particular the spherical harmonics and Legendre polynomials for any dimension, available to undergraduates studying physics or mathematics. With this audience in mind, nearly all details of the calculations and proofs are written out, and extensive background material is covered before beginning the main subject matter. The reader is assumed to have knowledge of multivariable calc...
Delimiting Maximal Kissing Configurations in Four Dimensions
Altschuler, Eric Lewin
2013-01-01
How many unit $n-$dimensional spheres can simultaneously touch or kiss a central $n-$dimensional unit sphere? Beyond mathematics this question has implications for fields such as cryptography and the structure of biologic and chemical macromolecules. The kissing number is only known for dimensions 1-4, 8 and 24 (2, 6, 12, 24, 240, 19650, respectively) and only particularly obvious for dimensions one and two. Indeed, in four dimensions it is not even known if Platonic polytope unique to that dimension known as the 24-cell is the unique kissing configuration. We have not been able to prove that the 24-cell is unique, but, using a physical approach utilizing the hopf map from four to three dimensions, we for the first time delimit the possible other configurations which could be kissing in four dimensions.
Necessity of Exact Calculation for Transition Probability
Institute of Scientific and Technical Information of China (English)
LIU Fu-Sui; CHEN Wan-Fang
2003-01-01
This paper shows that exact calculation for transition probability can make some systems deviate fromFermi golden rule seriously. This paper also shows that the corresponding exact calculation of hopping rate inducedby phonons for deuteron in Pd-D system with the many-body electron screening, proposed by Ichimaru, can explainthe experimental fact observed in Pd-D system, and predicts that perfection and low-dimension of Pd lattice are veryimportant for the phonon-induced hopping rate enhancement in Pd-D system.
Identification of Sustainable Architecture Dimensions
Leila Etminan; Siavash Rashidi Sharif Abad; Mansour Nikpor
2014-01-01
The main purpose in this research is identification of sustainable architecture dimensions. Nowadays, one of the most necessary complicated and main specifications of architecture with which architects are face is the issue of sustainability in various types of its interpretations. The issue of sustainability is interpretable and general according to many aspects. Therefore, it is necessary to identify this concept (architecture and its related categories). At the beginning of this discussion...
Energy Technology Data Exchange (ETDEWEB)
Lindgren, I.; Morrison, J.
1982-01-01
The unified description of atomic theory provided in this book bridges the gap between elementary books on quantum mechanics and present-day research in the field. Angular-momentum theory and the Hartree-Fock model are developed systematically and then applied to a number of physical problems. The treatment of many-body theory which then follows is based on a general form of the Rayleigh-Schroedinger perturbation theory, applicable to open-shell as well as closed-shell systems. The presentation in the book is based largely on graphical methods. Angular momentum graphs are used to represent the coupling between the spin and orbital angular momenta of the electrons, and the different terms in the perturbation expansion are expressed by means of 'Feynman-like' - or Goldstone - diagrams. These diagrams are evaluated using the angular-momentum graphs developed in the early part of the book. The formalism is applied to a number of problems in atomic physics, such as the electron-correlation energy, the electrostatic term structure and the spin-orbit and hyperfine interactions. The final chapter deals with the exp(S) or coupled-cluster formalism in the pair approximation, which appears to be the most promising approach for accurate calculations of the structure of real atomic and molecular systems.
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
In this paper, we are interested in the following general question: Given a module Mwhich has finite hollow dimension and which has a finite collection of submodules Ki (1≤i≤n) such that M=K1+... +Kn, can we find an expression for the hollow dimension of Min terms of hollow dimensions of modules built up in some way from K1 Kn? We prove the following theorem:Let Mbe an amply supplemented module having finite hollow dimension and let Ki (1≤i≤n) be a finite collection of submodules of Msuch that M=K1+...+Kn. Then the hollow dimension h(M) of Mis the sum of the hollow dimensions of Ki (1≤i≤n) ifand only if Ki is a supplement of K1+...+Ki-1+Ki+1+...+Kn in Mfor each 1≤i≤n.
Renormalization of dimension 6 gluon operators
Directory of Open Access Journals (Sweden)
HyungJoo Kim
2015-09-01
Full Text Available We identify the independent dimension 6 twist 4 gluon operators and calculate their renormalization in the pure gauge theory. By constructing the renormalization group invariant combinations, we find the scale invariant condensates that can be estimated in nonperturbative calculations and used in QCD sum rules for heavy quark systems in medium.
Renormalization of dimension 6 gluon operators
Energy Technology Data Exchange (ETDEWEB)
Kim, HyungJoo, E-mail: hugokm0322@gmail.com; Lee, Su Houng, E-mail: suhoung@yonsei.ac.kr
2015-09-02
We identify the independent dimension 6 twist 4 gluon operators and calculate their renormalization in the pure gauge theory. By constructing the renormalization group invariant combinations, we find the scale invariant condensates that can be estimated in nonperturbative calculations and used in QCD sum rules for heavy quark systems in medium.
Scientific Research: How Many Paradigms?
Strawn, George O.
2012-01-01
As Yogi Berra said, "Predictions are hard, especially about the future." In this article, the author offers a few forward-looking observations about the emerging impact of information technology on scientific research. Scientific research refers to a particular method for acquiring knowledge about natural phenomena. This method has two dimensions:…
Three-dimension reconstruction based on spatial light modulator
Deng, Xuejiao; Zhang, Nanyang; Zeng, Yanan; Yin, Shiliang; Wang, Weiyu
2011-02-01
Three-dimension reconstruction, known as an important research direction of computer graphics, is widely used in the related field such as industrial design and manufacture, construction, aerospace, biology and so on. Via such technology we can obtain three-dimension digital point cloud from a two-dimension image, and then simulate the three-dimensional structure of the physical object for further study. At present, the obtaining of three-dimension digital point cloud data is mainly based on the adaptive optics system with Shack-Hartmann sensor and phase-shifting digital holography. Referring to surface fitting, there are also many available methods such as iterated discrete fourier transform, convolution and image interpolation, linear phase retrieval. The main problems we came across in three-dimension reconstruction are the extraction of feature points and arithmetic of curve fitting. To solve such problems, we can, first of all, calculate the relevant surface normal vector information of each pixel in the light source coordinate system, then these vectors are to be converted to the coordinates of image through the coordinate conversion, so the expectant 3D point cloud get arise. Secondly, after the following procedures of de-noising, repairing, the feature points can later be selected and fitted to get the fitting function of the surface topography by means of Zernike polynomial, so as to reconstruct the determinand's three-dimensional topography. In this paper, a new kind of three-dimension reconstruction algorithm is proposed, with the assistance of which, the topography can be estimated from its grayscale at different sample points. Moreover, the previous stimulation and the experimental results prove that the new algorithm has a strong capability to fit, especially for large-scale objects .
Three-dimension reconstruction based on spatial light modulator
Energy Technology Data Exchange (ETDEWEB)
Deng Xuejiao; Zhang Nanyang; Zeng Yanan; Yin Shiliang; Wang Weiyu, E-mail: daisydelring@yahoo.com.cn [Huazhong University of Science and Technology (China)
2011-02-01
Three-dimension reconstruction, known as an important research direction of computer graphics, is widely used in the related field such as industrial design and manufacture, construction, aerospace, biology and so on. Via such technology we can obtain three-dimension digital point cloud from a two-dimension image, and then simulate the three-dimensional structure of the physical object for further study. At present, the obtaining of three-dimension digital point cloud data is mainly based on the adaptive optics system with Shack-Hartmann sensor and phase-shifting digital holography. Referring to surface fitting, there are also many available methods such as iterated discrete fourier transform, convolution and image interpolation, linear phase retrieval. The main problems we came across in three-dimension reconstruction are the extraction of feature points and arithmetic of curve fitting. To solve such problems, we can, first of all, calculate the relevant surface normal vector information of each pixel in the light source coordinate system, then these vectors are to be converted to the coordinates of image through the coordinate conversion, so the expectant 3D point cloud get arise. Secondly, after the following procedures of de-noising, repairing, the feature points can later be selected and fitted to get the fitting function of the surface topography by means of Zernike polynomial, so as to reconstruct the determinand's three-dimensional topography. In this paper, a new kind of three-dimension reconstruction algorithm is proposed, with the assistance of which, the topography can be estimated from its grayscale at different sample points. Moreover, the previous stimulation and the experimental results prove that the new algorithm has a strong capability to fit, especially for large-scale objects .
Directory of Open Access Journals (Sweden)
Quznetsov G.
2014-10-01
Full Text Available Each vector of state has its own corresponing element of the CayleyDickson algebra. Properties of a state vector require that this algebra was a normalized division algebra. By the Hurwitz and Frobenius theorems maximal dimension of s uch algebra is 8. Con- sequently, a dimension of corresponding complex state vectors is 4, and a dimension of the Clifford set elements is 4 × 4. Such set contains 5 matrices — among them — 3-diagonal. Hence, a dimension of the dot events space is equal to 3 + 1.
Many-body localization in dipolar systems.
Yao, N Y; Laumann, C R; Gopalakrishnan, S; Knap, M; Müller, M; Demler, E A; Lukin, M D
2014-12-12
Systems of strongly interacting dipoles offer an attractive platform to study many-body localized phases, owing to their long coherence times and strong interactions. We explore conditions under which such localized phases persist in the presence of power-law interactions and supplement our analytic treatment with numerical evidence of localized states in one dimension. We propose and analyze several experimental systems that can be used to observe and probe such states, including ultracold polar molecules and solid-state magnetic spin impurities. PMID:25541771
THE DISTRIBUTIONAL DIMENSION OF FRACTALS
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
In the book [1] H.Triebel introduces the distributional dimension of fractals in and distributional dimension, respectively. Thus we might say that the distributional dimension is an analytical definition for Hausdorff dimension. Therefore we can study Hausdorff dimension through the distributional dimension analytically.By discussing the distributional dimension, this paper intends to set up a criterion for estimating the upper and lower bounds of Hausdorff dimension analytically. Examples illustrating the criterion are included in the end.
Classical equation of motion and Anomalous dimensions at leading order
Nii, Keita
2016-01-01
Motivated by a recent paper by Rychkov-Tan \\cite{Rychkov:2015naa}, we calculate the anomalous dimensions of the composite operators at the leading order in various models including a $\\phi^3$-theory in $(6-\\epsilon)$ dimensions. The method presented here relies only on the classical equation of motion and the conformal symmetry. In case that only the leading expressions of the critical exponents are of interest, it is sufficient to reduce the multiplet recombination discussed in \\cite{Rychkov:2015naa} to the classical equation of motion. We claim that in many cases the use of the classical equations of motion and the CFT constraint on two- and three-point functions completely determine the leading behavior of the anomalous dimensions at the Wilson-Fisher fixed point without any input of the Feynman diagrammatic calculation. The method developed here is closely related to the one presented in \\cite{Rychkov:2015naa} but based on a more perturbative point of view.
Entropies and fractal dimensions
Sparavigna, Amelia Carolina
2016-01-01
In this paper, we discuss the relation between entropy and the fractal dimension, a statistical index which is measuring the complexity of a given pattern, embedded in given spatial dimensions. We will consider the Shannon entropy and the generalized entropies of Tsallis and Kaniadakis
Gorenstein homological dimensions
DEFF Research Database (Denmark)
Holm, Henrik Granau
2004-01-01
In basic homological algebra, the projective, injective and 2at dimensions of modules play an important and fundamental role. In this paper, the closely related Gorenstein projective, Gorenstein injective and Gorenstein 2at dimensions are studied. There is a variety of nice results about Gorenste...
DEFF Research Database (Denmark)
Lykke, Marianne; Jantzen, Christian
2016-01-01
The present study develops a set of 10 dimensions based on a systematic understanding of the concept of experience as a holistic psychological. Seven of these are derived from a psychological conception of what experiencing and experiences are. Three supplementary dimensions spring from the obser...
Dynamics of Chaotic Inflation with Variable Space Dimension
Nasseri, Forough
2002-01-01
Within the framework of a model Universe with variable space dimension, we study chaotic inflation with the potential $m^2\\phi^2/2$, and calculate the dynamical solutions of the inflaton field, variable space dimension, scale factor, and their interdependence during the inflationary epoch. We show that the characteristic of the variability of the space dimension causes the inflationary epoch in the variable space dimension to last longer than the inflationary epoch in the constant space dimen...
Castro, Carlos; Granik, Alex; Naschie, M. S. El
2000-01-01
A Cantorian fractal spacetime, a family member of von Neumann's noncommutative geometry is introduced as a geometry underlying a new relativity theory which is similar to the relation between general relativity and Riemannian geometry. Based on this model and the new relativity theory an ensemble distribution of all the dimensions of quantum spacetime is derived with the help of Fermat grand theorem. The calculated average dimension is very close to the value of $4+\\phi^3 $ (where $\\phi$ is t...
Sign (di)Lemma for Dimension Shifting
Indian Academy of Sciences (India)
Nitin Nitsure
2009-04-01
There is a surprising occurrence of some minus signs in the isomorphisms produced in the well-known technique of dimension shifting in calculating derived functors in homological algebra. We explicitly determine these signs. Getting these signs right is important in order to avoid basic contradictions. We illustrate the result – which we call as the sign lemma for dimension shifting – by some de Rham cohomology and Chern class considerations for compact Riemann surfaces.
DEFF Research Database (Denmark)
Høskuldsson, Agnar
1996-01-01
Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four of these cri......Determination of the proper dimension of a given linear model is one of the most important tasks in the applied modeling work. We consider here eight criteria that can be used to determine the dimension of the model, or equivalently, the number of components to use in the model. Four...... the basic problems in determining the dimension of linear models. Then each of the eight measures are treated. The results are illustrated by examples....
Dimensions of Creative Evaluation
DEFF Research Database (Denmark)
Christensen, Bo; Ball, Linden J.
2016-01-01
continue. Each dimension was associated with a specific underpinning ‘logic’ determining how these dimensions were evaluated in practice. Our analysis clarified how these dimensions triggered reasoning strategies such as running mental simulations or making design suggestions, ranging from ‘go......We examined evaluative reasoning taking place during expert ‘design critiques’. We focused on key dimensions of creative evaluation (originality, functionality and aesthetics) and ways in which these dimensions impact reasoning strategies and suggestions offered by experts for how the student could....../kill’ decisions to loose recommendations to continue without directional steer. The findings advance our theoretical understanding of evaluation behaviour in design and alert practicing design evaluators to the nature and consequences of their critical appraisals....
Socio-cultural dimensions to sharpen designer's cultural eyeglasses
Van Boeijen, A.G.C.
2013-01-01
This paper answers the question, how the dimensions that have been developed by anthropologists to typify cultures, can support designers in user-centred design processes. An analysis and evaluation of the use of cultural dimensions in design projects was performed. Although many of the dimensions f
Dimension Estimates for Certain Sets of Infinite Complex Continued Fractions
Directory of Open Access Journals (Sweden)
J. Neunhäuserer
2013-01-01
Full Text Available We prove upper and lower estimates on the Hausdorff dimension of sets of infinite complex continued fractions with finitely many prescribed Gaussian integers. Particulary we will conclude that the dimension of theses sets is not zero or two and there are such sets with dimension greater than one and smaller than one.
The Cultural Dimensions of Language Teaching and Learning
Risager, Karen
2011-01-01
Language teaching and learning has many different cultural dimensions, and over the years more and more of these have been the subject of research. The first dimension to be explored was that of content: the images of target language countries and the world that were offered in textbooks and presented in class. The next dimension was that of the…
van Houselt, A.; Schäfer, J.; Zandvliet, H. J. W.; Claessen, R.
2013-01-01
and should be replaced by the Luttinger liquid theory [2, 3]. In 1D electron systems electron-electron interactions play a very prominent role, and one of the most exciting predictions is that the electron loses its identity and separates into two collective excitations of the quantum mechanical many body system: a spinon that carries spin without charge, and a holon that carries the positive charge of a hole without its spin. In this special section, we have attempted to collect a series of papers that gives an impression of the current status of this rapidly evolving field. The first article is a comprehensive review by Kurt Schönhammer that provides the reader with an introduction into the exciting theory of the 1D electron system as well as its mathematical formalism. Acknowledgments We would like to thank the editorial staff of Journal of Physics: Condensed Matter for their help in producing this special section. We hope that it conveys some of the excitement and significance of this rapidly emerging field. References [1]Mermin N D and Wagner H 1966 Phys. Rev. Lett. 17 1133 [2]Haldane F D M 1981 J. Phys. C: Solid State Phys. 14 2585 [3]Voit J 1995 Rep. Prog. Phys. 58 977 Physics in one dimension contents Physics in one dimensionA van Houselt, J Schäfer, H J W Zandvliet and R Claessen Physics in one dimension: theoretical concepts for quantum many-body systemsK Schönhammer Local density of states of the one-dimensional spinless fermion modelE Jeckelmann Local spectral properties of Luttinger liquids: scaling versus nonuniversal energy scalesD Schuricht, S Andergassen and V Meden Spin ladders and quantum simulators for Tomonaga-Luttinger liquidsS Ward, P Bouillot, H Ryll, K Kiefer, K W Krämer, Ch Rüegg, C Kollath and T Giamarchi Peierls to superfluid crossover in the one-dimensional, quarter-filled Holstein modelM Hohenadler and F F Assaad Pressure-dependent structural and electronic properties of quasi-one-dimensional (TMTTF)2PF6E Rose, C Loose, J Kortus, A
van Houselt, A.; Schäfer, J.; Zandvliet, H. J. W.; Claessen, R.
2013-01-01
and should be replaced by the Luttinger liquid theory [2, 3]. In 1D electron systems electron-electron interactions play a very prominent role, and one of the most exciting predictions is that the electron loses its identity and separates into two collective excitations of the quantum mechanical many body system: a spinon that carries spin without charge, and a holon that carries the positive charge of a hole without its spin. In this special section, we have attempted to collect a series of papers that gives an impression of the current status of this rapidly evolving field. The first article is a comprehensive review by Kurt Schönhammer that provides the reader with an introduction into the exciting theory of the 1D electron system as well as its mathematical formalism. Acknowledgments We would like to thank the editorial staff of Journal of Physics: Condensed Matter for their help in producing this special section. We hope that it conveys some of the excitement and significance of this rapidly emerging field. References [1]Mermin N D and Wagner H 1966 Phys. Rev. Lett. 17 1133 [2]Haldane F D M 1981 J. Phys. C: Solid State Phys. 14 2585 [3]Voit J 1995 Rep. Prog. Phys. 58 977 Physics in one dimension contents Physics in one dimensionA van Houselt, J Schäfer, H J W Zandvliet and R Claessen Physics in one dimension: theoretical concepts for quantum many-body systemsK Schönhammer Local density of states of the one-dimensional spinless fermion modelE Jeckelmann Local spectral properties of Luttinger liquids: scaling versus nonuniversal energy scalesD Schuricht, S Andergassen and V Meden Spin ladders and quantum simulators for Tomonaga-Luttinger liquidsS Ward, P Bouillot, H Ryll, K Kiefer, K W Krämer, Ch Rüegg, C Kollath and T Giamarchi Peierls to superfluid crossover in the one-dimensional, quarter-filled Holstein modelM Hohenadler and F F Assaad Pressure-dependent structural and electronic properties of quasi-one-dimensional (TMTTF)2PF6E Rose, C Loose, J Kortus, A
Stable simulations of many fermion systems
International Nuclear Information System (INIS)
As the inverse temperature β becomes large, the diverse numerical scales present in exp(-βH) plague simulations of many-fermion systems on finite-precision computers. Representation of matrices in factorized form stabilizes these calculations, allowing efficient, low-temperature studies of condensed-matter models
Extra dimensions round the corner?
Energy Technology Data Exchange (ETDEWEB)
Abel, S. [Theory Division, CERN, Geneva (Switzerland)
1999-06-01
How many dimensions are we living in? This question is fundamental and yet, astonishingly, it remains unresolved. Of course, on the everyday level it appears that we are living in four dimensions three space plus one time dimension. But in recent months theoretical physicists have discovered that collisions between high-energy particles at accelerators may reveal the presence of extra space-time dimensions. On scales where we can measure the acceleration of falling objects due to gravity or study the orbital motion of planets or satellites, the gravitational force seems to be described by a 1/r{sup 2} law. The most sensitive direct tests of the gravitational law are based on torsion-balance experiments that were first performed by Henry Cavendish in 1798. However, the smallest scales on which this type of experiment can be performed are roughly 1 mm (see J C Long, H W Chan and J C Price 1999 Nucl. Phys. B 539 23). At smaller distances, objects could be gravitating in five or more dimensions that are rolled up or ''compactified'' - an idea that is bread-and-butter to string theorists. Most string theorists however believe that the gravitational effects of compact extra dimensions are too small to be observed. Now Nima Arkani-Hamed from the Stanford Linear Accelerator Center (SLAC) in the US, Savas Dimopoulos at Stanford University and Gia Dvali, who is now at New York University, suggest differently (Phys. Lett. B 1998 429 263). They advanced earlier ideas from string theory in which the strong, weak and electromagnetic forces are confined to membranes, like dirt particles trapped in soap bubbles, while the gravitational force operates in the entire higher-dimensional volume. In their theory extra dimensions should have observable effects inside particle colliders such as the Tevatron accelerator at Fermilab in the US or at the future Large Hadron Collider at CERN. The effect will show up as an excess of events in which a single jet of particles
Extra dimensions round the corner?
International Nuclear Information System (INIS)
How many dimensions are we living in? This question is fundamental and yet, astonishingly, it remains unresolved. Of course, on the everyday level it appears that we are living in four dimensions three space plus one time dimension. But in recent months theoretical physicists have discovered that collisions between high-energy particles at accelerators may reveal the presence of extra space-time dimensions. On scales where we can measure the acceleration of falling objects due to gravity or study the orbital motion of planets or satellites, the gravitational force seems to be described by a 1/r2 law. The most sensitive direct tests of the gravitational law are based on torsion-balance experiments that were first performed by Henry Cavendish in 1798. However, the smallest scales on which this type of experiment can be performed are roughly 1 mm (see J C Long, H W Chan and J C Price 1999 Nucl. Phys. B 539 23). At smaller distances, objects could be gravitating in five or more dimensions that are rolled up or ''compactified'' - an idea that is bread-and-butter to string theorists. Most string theorists however believe that the gravitational effects of compact extra dimensions are too small to be observed. Now Nima Arkani-Hamed from the Stanford Linear Accelerator Center (SLAC) in the US, Savas Dimopoulos at Stanford University and Gia Dvali, who is now at New York University, suggest differently (Phys. Lett. B 1998 429 263). They advanced earlier ideas from string theory in which the strong, weak and electromagnetic forces are confined to membranes, like dirt particles trapped in soap bubbles, while the gravitational force operates in the entire higher-dimensional volume. In their theory extra dimensions should have observable effects inside particle colliders such as the Tevatron accelerator at Fermilab in the US or at the future Large Hadron Collider at CERN. The effect will show up as an excess of events in which a single jet of particles is produced with no
Epistemic Sensibility: Third Dimension of Virtue Epistemology
Belbase, Shashidhar
2012-01-01
The author tries to argue how epistemic sensibility as virtue sensibility can complement virtue epistemology. Many philosophers interrelated virtue reliabilism (e.g., Brogaard, 2006) and virtue responsibilism (e.g., Code, 1987) to virtue epistemology as two dimensions with many diverging and a few converging characters. The possible new dimension…
Rucker, Rudy
2014-01-01
""This is an invigorating book, a short but spirited slalom for the mind."" - Timothy Ferris, The New York Times Book Review ""Highly readable. One is reminded of the breadth and depth of Hofstadter's Gödel, Escher, Bach."" - Science""Anyone with even a minimal interest in mathematics and fantasy will find The Fourth Dimension informative and mind-dazzling... [Rucker] plunges into spaces above three with a zest and energy that is breathtaking."" - Martin Gardner ""Those who think the fourth dimension is nothing but time should be encouraged to read The Fourth Dimension, along with anyone else
Directory of Open Access Journals (Sweden)
Goparaju Purna SUDHAKAR
2014-01-01
Full Text Available Popularity ofteams is growing in 21st Century. Organizations are getting theirwork done through different types of teams. Teams have proved that thecollective performance is more than the sum of the individual performances.Thus, the teams have got different dimensions such as quantitative dimensionsand qualitative dimensions. The Quantitative dimensions of teams such as teamperformance, team productivity, team innovation, team effectiveness, teamefficiency, team decision making and team conflicts and Qualitative dimensionsof teams such as team communication, team coordination, team cooperation, teamcohesion, team climate, team creativity, team leadership and team conflictshave been discussed in this article.
Dimension control of Superradiance
Hill, Tyler; Hui Deng Collaboration; Barry C. Sanders Collaboration
2016-05-01
We develop a theory for quantum dipole-dipole coupling when the electromagnetic fields are confined to an open line, open plane, or open space, commensurate with experimental capability for collective atomic effects subject to dimensional confinement. Our mathematical model naturally interpolates for all real dimension between one dimension for the line to three dimensions for open space. We show how superradiant emission can be controlled by dimensional confinement, including near-field and dipole-orientation effects, and we propose a two-dimensional confinement experiment to test our theory's efficacy. University of Michigan.
Loos, Pierre-François; Ball, Caleb J; Gill, Peter M W
2015-02-01
We report benchmark results for one-dimensional (1D) atomic and molecular systems interacting via the Coulomb operator |x|(-1). Using various wavefunction-type approaches, such as Hartree-Fock theory, second- and third-order Møller-Plesset perturbation theory and explicitly correlated calculations, we study the ground state of atoms with up to ten electrons as well as small diatomic and triatomic molecules containing up to two electrons. A detailed analysis of the 1D helium-like ions is given and the expression of the high-density correlation energy is reported. We report the total energies, ionization energies, electron affinities and other physical properties of the many-electron 1D atoms and, using these results, we construct the 1D analog of Mendeleev's periodic table. We find that the 1D periodic table contains only two groups: the alkali metals and the noble gases. We also calculate the dissociation curves of several 1D diatomics and study the chemical bond in H2(+), HeH(2+), He2(3+), H2, HeH(+) and He2(2+). We find that, unlike their 3D counterparts, 1D molecules are primarily bound by one-electron bonds. Finally, we study the chemistry of H3(+) and we discuss the stability of the 1D polymer resulting from an infinite chain of hydrogen atoms. PMID:25518906
Loos, Pierre-François; Gill, Peter M W
2014-01-01
We report benchmark results for one-dimensional (1D) atomic and molecular systems interacting via the Coulomb operator $|x|^{-1}$. Using various wavefunction-type approaches, such as Hartree-Fock theory, second- and third-order M{\\o}ller-Plesset perturbation theory and explicitly correlated calculations, we study the ground state of atoms with up to ten electrons as well as small diatomic and triatomic molecules containing up to two electrons. A detailed analysis of the 1D helium-like ions is given and the expression of the high-density correlation energy is reported. We report the total energies, ionization energies, electron affinities and other interesting properties of the many-electron 1D atoms and, based on these results, we construct the 1D analog of Mendeleev's periodic table. We find that the 1D periodic table contains only two groups: the alkali metals and the noble gases. We also calculate the dissociation curves of various 1D diatomics and study the chemical bond in H$_2^+$, HeH$^{2+}$, He$_2^{3+}...
DEFF Research Database (Denmark)
Due, Jesper Jørgen; Madsen, Jørgen Steen; Jensen, Carsten Strøby
En analyse af EU's institutioner og udviklingen af den sociale dimension i forbindelse med etbaleringen af det indre marked med særlig henblik på effekterne på det danske aftalesystem.......En analyse af EU's institutioner og udviklingen af den sociale dimension i forbindelse med etbaleringen af det indre marked med særlig henblik på effekterne på det danske aftalesystem....
Barvinsky, A O; Solodukhin, Sergey N.
2003-01-01
We study the propagating gravitational waves as a tool to probe the extra dimensions. In the set-up with one compact extra dimension and non-gravitational physics resigning on the 4-dimensional subspace (brane) of 5-dimensional spacetime we find the Green's function describing the propagation of 5-dimensional signal along the brane. The Green's function has a form of the sum of contributions from large number of images due to the compactness of the fifth dimension. Additionally, a peculiar feature of the causal wave propagation in five dimensions (making a five-dimensional spacetime very much different from the familiar four-dimensional case) is that the entire region inside the past light-cone contributes to the signal at the observation point. The 4-dimensional propagation law is nevertheless reproduced at large (compared to the size of extra dimension) intervals from the source as a superposition of signals from large number of images. The fifth dimension however shows up in the form of corrections to the ...
EFFECTIVE DISCHARGE CALCULATION GUIDE
Institute of Scientific and Technical Information of China (English)
D.S.BIEDENHARN; C.R.THORNE; P.J.SOAR; R.D.HEY; C.C.WATSON
2001-01-01
This paper presents a procedure for calculating the effective discharge for rivers with alluvial channels.An alluvial river adjusts the bankfull shape and dimensions of its channel to the wide range of flows that mobilize the boundary sediments. It has been shown that time-averaged river morphology is adjusted to the flow that, over a prolonged period, transports most sediment. This is termed the effective discharge.The effective discharge may be calculated provided that the necessary data are available or can be synthesized. The procedure for effective discharge calculation presented here is designed to have general applicability, have the capability to be applied consistently, and represent the effects of physical processes responsible for determining the channel, dimensions. An example of the calculations necessary and applications of the effective discharge concept are presented.
Stable many-to-many matchings with contracts
Klaus, B.E.; Walzl, M.
2006-01-01
We consider several notions of setwise stability for many-to-many matching markets with contracts and provide an analysis of the relations between the resulting stable sets and pairwise stable sets for general, substitutable, and strongly substitutable preferences. Apart from obtaining “set inclusion results'''' on all three domains, we prove that for substitutable preferences the set of pairwise stable matchings is nonempty and coincides with the set of weakly setwise stable matchings. For s...
A variational principle for the Hausdorff dimension of fractal sets
DEFF Research Database (Denmark)
Olsen, Lars; Cutler, Colleen D.
1994-01-01
Matematik, fraktal (fractal), Hausdorff dimension, Renyi dimension, pakke dimension (packing dimension)......Matematik, fraktal (fractal), Hausdorff dimension, Renyi dimension, pakke dimension (packing dimension)...
Dynamics of Particles Near Black Hole with Higher Dimensions
Sharif, M
2016-01-01
This paper explores the dynamics of particles in higher dimensions. For this purpose, we discuss some interesting features related to the motion of particles near Myers-Perry black hole with arbitrary extra dimensions as well as single non-zero spin parameter. Assuming it as a supermassive black hole at the center of galaxy, we calculate red-blue shifts in the equatorial plane for the far away observer as well as corresponding black hole parameters of the photons. Next, we study the Penrose process and find that the energy gain of particle depends on the variation of black hole dimensions. Finally, we discuss the center of mass energy for eleven dimensions which indicates similar behavior as that of four dimensions but it is higher in four dimensions than five or more dimensions. We conclude that higher dimensions have a great impact on the particle dynamics.
If so many are "few", how few are "many"?
Directory of Open Access Journals (Sweden)
Stefan eHeim
2015-04-01
Full Text Available The scope of reference of a word’s meaning can be highly variable. We present a novel paradigm to investigate the flexible interpretation of word meaning. We focus on quantifiers such as „many or „few, a class of words that depends on number knowledge but can be interpreted in a flexible manner. Healthy young adults performed a truth value judgment task on pictorial arrays of varying amounts of blue and yellow circles, deciding whether the sentence Many/few of the circles are yellow was an adequate description of the stimulus. The study consisted of two experiments, one focusing on „many, one on „few. Each experiment had three blocks. In a first baseline block, each individual’s criterion for „many and „few was assessed. In a second adaptation block, subjects received feedback about their decisions that was different from their initial judgments in an effort to evaluate the flexibility of a subject’s interpretation. A third test block assessed whether adaptation of quantifier meaning induced in block 2 then was generalized to alter a subject’s baseline meaning for „many and „few. In Experiment 1, a proportion of yellow circles as small as 40% was reinforced as „many; in Experiment 2, a proportion of yellow circles as large as 60% was reinforced as „few. Subjects learned the new criterion for „many in Experiment 1, which also affected their criterion for „few although it had never been mentioned. Likewise, in Experiment 2, subjects changed their criterion for „few, with a comparable effect on the criterion for „many which was not mentioned. Thus, the meaning of relational quantifiers like many and „few is flexible and can be adapted. Most importantly, adapting the criterion for one quantifier (e.g. „many also appeared to affect the reciprocal quantifier (in this case, „few. Implications of this result for psychological interventions and for investigations of the neurobiology of the language
Karsai, Szilvia; Forgács-Dajka, Emese; Pósfay, Péter
2016-01-01
We present the correspondence between non-interacting multi-hadron fermion star equation of state in the many-flavor limit and the degrees of freedom of a Kaluza\\,--\\,Klein compact star. Many flavors can be interpreted in this framework as one extra compacti\\-fied spatial dimension with various, more-and-more massive hadron state excitations. The effect of increasing the degrees of freedom was investigated on the equation of state and in connection with the mass-radius relation, $M(R)$. The maximum mass of the star, $M_{\\mathrm{max}}$ were also calculated as a function of the maximum number of excited states, $n$ and the size of the compactified extra dimension, $R_{\\mathrm{c}}$.
A KAM Theorem for Reversible Systems of Infinite Dimension
Institute of Scientific and Technical Information of China (English)
Shun Qing CHEN; Xiao Ping YUAN
2007-01-01
For reversible systems of infinite dimension we prove an infinitely dimensional KAM theoremwith an application to the network of weakly coupled oscillators of friction. The KAM theorem showsthat there are many invariant tori of infinite dimension, and thus many almost periodic solutions, forthe reversible systems.
Numerical study of unitary fermions in one spatial dimension
Endres, Michael G
2013-01-01
I perform lattice Monte Carlo studies of universal four-component fermion systems in one spatial dimension. Continuum few-body observables (i.e., ground state energies and integrated contact densities) are determined for both unpolarized and polarized systems of up to eight fermions confined to a harmonic trap. Estimates of the continuum energies for four and five trapped fermions show agreement with exact analytic calculations to within approximately one percent statistical uncertainties. Continuum many-body observables are determined for unpolarized systems of up to 88 fermions confined to a finite box, and 56 fermions confined to a harmonic trap. Results are reported for universal quantities such as the Bertsch parameter, defined as the energy of the untrapped many-body system in units of the corresponding free-gas energy, and its subleading correction at large but finite scattering length. Two independent estimates of these quantities are obtained from thermodynamic limit extrapolations of continuum extra...
Symmetry of many-electron systems
Kaplan, I G
2013-01-01
Symmetry of Many-Electron Systems discusses the group-theoretical methods applied to physical and chemical problems. Group theory allows an individual to analyze qualitatively the elements of a certain system in scope. The text evaluates the characteristics of the Schrodinger equations. It is proved that some groups of continuous transformation from the Lie groups are useful in identifying conditions and in developing wavefunctions. A section of the book is devoted to the utilization of group-theoretical methods in quantal calculations on many-electron systems. The focus is on the use of group
Depression Plagues Many with COPD
... nlm.nih.gov/medlineplus/news/fullstory_159436.html Depression Plagues Many With COPD Studies found 1 in ... pulmonary disorder (COPD) may raise the risk of depression among patients with the incurable respiratory illness, two ...
Depression Plagues Many with COPD
... page: https://medlineplus.gov/news/fullstory_159436.html Depression Plagues Many With COPD Studies found 1 in ... pulmonary disorder (COPD) may raise the risk of depression among patients with the incurable respiratory illness, two ...
International Nuclear Information System (INIS)
We show that realistic interactions derived from Brueckner calculations based on the N-N potentials, give excellent spectroscopy provided their monopole behaviour is corrected. The latter is related to saturation properties of nuclei and demands the introduction of a non analytic dependence of the effective interaction on the particle number. This mechanism is certainly related to a density dependence and no need is felt empirically of forces of rank higher than two-some new results concern the theory of spectral distributions: the parametrization of the monopole feld and calculations of traces of H and H2 at fixed n,t,v (number, isospin, seniority). This results are useful in the context of quasiconfiguration theory to establish the foundations of Shell Model calculations in the ZBM spaces
Control of safety factor profile in infinite dimension tokamak plasmas
International Nuclear Information System (INIS)
The increasing energy needs of the world population require the development, the control and the supply of new forms of energy. In this context, nuclear fusion is a track of extremely promising research. World project ITER is intended to prove the scientific and technical feasibility of nuclear fusion. One of the many key-goal is the control of the current profile spatial distribution in plasmas of tokamak, which is one of the main parameter for the stability and the performance of the experiments. The spatio-temporal evolution of this current is described by a set of nonlinear partial differential equations. In this document stabilization is proposed considering robust control of current profile spatial distribution in infinite dimension. Two approaches are proposed: the first one is based on sliding mode approach and the second one (of type proportional and proportional integral) is based on the Lyapunov functions in infinite dimension. The design of the control law is based on the 1D equation resistive diffusion of the magnetic flux. The control laws are calculated in infinite dimension without space discretization. (author)
Cultural dimensions and innovation
Directory of Open Access Journals (Sweden)
Anna Strychalska-Rudzewicz
2015-11-01
Full Text Available This paper examines the effect of culture’s dimensions on national innovation index. The results of Pearson correlation coefficient between culture dimensions and the Global Innovation Index (GII are very similar to the results obtained in the case of Summary Innovation Index (SII in European countries. The strong negative correlation was observed in the case of power distance and uncertainty avoidance whereas individualism has a positive effect on innovation index. The results suggest that low power distance and uncertainty-accepting countries may be more innovative than high power distance and uncertainty-avoiding societies.
Leifsson, Patrik
2006-01-01
Fractal analysis is an important tool when we need to study geometrical objects less regular than ordinary ones, e.g. a set with a non-integer dimension value. It has developed intensively over the last 30 years which gives a hint to its young age as a branch within mathematics. In this thesis we take a look at some basic measure theory needed to introduce certain definitions of fractal dimensions, which can be used to measure a set's fractal degree. Comparisons of these definitions are done ...
Inflation from extra dimensions
Levin, J
1994-01-01
A gravity-driven inflation is shown to arise from a simple higher dimensional universe. In vacuum, the shear of n>1 contracting dimensions is able to inflate the remaining three spatial dimensions. Said another way, the expansion of the 3-volume is accelerated by the contraction of the n-volume. Upon dimensional reduction, the theory is equivalent to a four dimensional cosmology with a dynamical Planck mass. A connection can therefore be made to recent examples of inflation powered by a dilaton kinetic energy. Unfortunately, the graceful exit problem encountered in dilaton cosmologies will haunt this cosmology as well.
Many-Body Basis Set Superposition Effect.
Ouyang, John F; Bettens, Ryan P A
2015-11-10
The basis set superposition effect (BSSE) arises in electronic structure calculations of molecular clusters when questions relating to interactions between monomers within the larger cluster are asked. The binding energy, or total energy, of the cluster may be broken down into many smaller subcluster calculations and the energies of these subsystems linearly combined to, hopefully, produce the desired quantity of interest. Unfortunately, BSSE can plague these smaller fragment calculations. In this work, we carefully examine the major sources of error associated with reproducing the binding energy and total energy of a molecular cluster. In order to do so, we decompose these energies in terms of a many-body expansion (MBE), where a "body" here refers to the monomers that make up the cluster. In our analysis, we found it necessary to introduce something we designate here as a many-ghost many-body expansion (MGMBE). The work presented here produces some surprising results, but perhaps the most significant of all is that BSSE effects up to the order of truncation in a MBE of the total energy cancel exactly. In the case of the binding energy, the only BSSE correction terms remaining arise from the removal of the one-body monomer total energies. Nevertheless, our earlier work indicated that BSSE effects continued to remain in the total energy of the cluster up to very high truncation order in the MBE. We show in this work that the vast majority of these high-order many-body effects arise from BSSE associated with the one-body monomer total energies. Also, we found that, remarkably, the complete basis set limit values for the three-body and four-body interactions differed very little from that at the MP2/aug-cc-pVDZ level for the respective subclusters embedded within a larger cluster. PMID:26574311
Analysis on structure of igneous formation with fractal dimension of logs
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
Reflecting the structure of igneous formation by calculating fractal dimension of logs, the fractal dimension of pyroclastic is larger than lava. Structure of pyroclastic is more complicated than that of lava, so reflecting the structure of igneous formation's complexity with fractal dimension is feasible. It is feasible to refleet the structure of igneous formation's complexity with fractal dimension.
DEFF Research Database (Denmark)
Eskjær, Mikkel Fugl
2013-01-01
is largely dependent on regional media systems, yet the role this regional dimension plays has been largely overlooked. This article presents a comparative study of climate-change coverage in three geo-cultural regions, The Middle East, Scandinavia, and North America, and explores the link between global...
Bertel, Erminald
2013-01-01
Due to progress in nanotechnology high-quality quantum wires can nowadays be fabricated. The behavior of particles in one dimension differs significantly from that in three-dimensional (3D) systems, yet the physics of such low-dimensional systems is generally not very well represented in standard undergraduate or graduate curricula. For instance,…
Stephenson, Paul
2012-01-01
The first word of this item is "imagine". This instruction has the potential to signal a journey through a world of geometry that might leave you spellbound. On the other hand, it could be the start of a roller-coaster ride through three dimensions that will tax both your imagination, and your powers of visualisation. It is likely that you will…
nuclear reactor design calculations
International Nuclear Information System (INIS)
In this work , the sensitivity of different reactor calculation methods, and the effect of different assumptions and/or approximation are evaluated . A new concept named error map is developed to determine the relative importance of different factors affecting the accuracy of calculations. To achieve this goal a generalized, multigroup, multi dimension code UAR-DEPLETION is developed to calculate the spatial distribution of neutron flux, effective multiplication factor and the spatial composition of a reactor core for a period of time and for specified reactor operating conditions. The code also investigates the fuel management strategies and policies for the entire fuel cycle to meet the constraints of material and operating limitations
Just How Many Different Forms of Culture Are There?
Cohen, Adam B.
2010-01-01
Responds to comments by H. Takooshian and J. K. Tebes on the current author's original article, "Many forms of culture". The current author argued that psychologists tend to focus on too narrow a set of cultures (ethnic and national cultures) and some dimensions of those cultures (individualism-collectivism, independence-interdependence). He then…
Earthquakes Threaten Many American Schools
Bailey, Nancy E.
2010-01-01
Millions of U.S. children attend schools that are not safe from earthquakes, even though they are in earthquake-prone zones. Several cities and states have worked to identify and repair unsafe buildings, but many others have done little or nothing to fix the problem. The reasons for ignoring the problem include political and financial ones, but…
Gold, Paul E.
2006-01-01
Results from studies of retrograde amnesia provide much of the evidence for theories of memory consolidation. Retrograde amnesia gradients are often interpreted as revealing the time needed for the formation of long-term memories. The rapid forgetting observed after many amnestic treatments, including protein synthesis inhibitors, and the parallel…
Conscious observers clarify many worlds
Simon, Christoph
2009-01-01
In this brief note I argue that putting conscious observers at the center of the considerations clarifies and strengthens the many-worlds interpretation. The basic assumption, which seems extremely plausible based on our current understanding of the brain and of decoherence, is that quantum states corresponding to distinct conscious experiences have to be orthogonal. I show that, once this is accepted, probabilistic measurement outcomes corresponding to basis elements and following Born's rule emerge naturally from global unitary dynamics.
Many-particle interference beyond many-boson and many-fermion statistics
DEFF Research Database (Denmark)
Tichy, Malte C.; Tiersch, Markus; Mintert, Florian;
2012-01-01
that the collective interference of three or more particles leads to much more diverse behavior than expected from the boson–fermion dichotomy known from quantum statistical mechanics. The emerging complexity of many-particle interference is tamed by a simple law for the strict suppression of events in the Bell...... multiport beam splitter. The law shows that counting events are governed by widely species-independent interference, such that bosons and fermions can even exhibit identical interference signatures, while their statistical character remains subordinate. Recent progress in the preparation of tailored many...
Brightness and darkness as perceptual dimensions.
Directory of Open Access Journals (Sweden)
Tony Vladusich
2007-10-01
Full Text Available A common-sense assumption concerning visual perception states that brightness and darkness cannot coexist at a given spatial location. One corollary of this assumption is that achromatic colors, or perceived grey shades, are contained in a one-dimensional (1-D space varying from bright to dark. The results of many previous psychophysical studies suggest, by contrast, that achromatic colors are represented as points in a color space composed of two or more perceptual dimensions. The nature of these perceptual dimensions, however, presently remains unclear. Here we provide direct evidence that brightness and darkness form the dimensions of a two-dimensional (2-D achromatic color space. This color space may play a role in the representation of object surfaces viewed against natural backgrounds, which simultaneously induce both brightness and darkness signals. Our 2-D model generalizes to the chromatic dimensions of color perception, indicating that redness and greenness (blueness and yellowness also form perceptual dimensions. Collectively, these findings suggest that human color space is composed of six dimensions, rather than the conventional three.
Cultural dimensions of learning
Eyford, Glen A.
1990-06-01
How, what, when and where we learn is frequently discussed, as are content versus process, or right brain versus left brain learning. What is usually missing is the cultural dimension. This is not an easy concept to define, but various aspects can be identified. The World Decade for Cultural Development emphasizes the need for a counterbalance to a quantitative, economic approach. In the last century poets also warned against brutalizing materialism, and Sorokin and others have described culture more recently in terms of cohesive basic values expressed through aesthetics and institutions. Bloom's taxonomy incorporates the category of affective learning, which internalizes values. If cultural learning goes beyond knowledge acquisition, perhaps the surest way of understanding the cultural dimension of learning is to examine the aesthetic experience. This can use myths, metaphors and symbols, and to teach and learn by using these can help to unlock the human potential for vision and creativity.
Warped Universal Extra Dimensions
Medina, Anibal D
2010-01-01
We consider a 5D warped scenario with a KK-parity symmetry, where the non-trivial warping arises from the dynamics that stabilizes the size of the extra dimension. Generically, the lightest Kaluza-Klein (KK) particle is the first excitation of the radion field, while the next-to-lightest Kaluza-Klein particle is either the first excitation of the (RH) top quark or the first KK-parity odd Higgs. All these masses are expected to be of order the electroweak scale. We present simple analytical expressions for the masses and wavefunctions of the lowest lying KK modes, and derive the Feynman rules necessary for phenomenological applications. The framework allows to interpolate between a strongly warped scenario a la Randall-Sundrum (RS), and a weakly warped scenario that shares properties of both RS and Universal Extra Dimensions models.
A Two-Dimension Process in Explaining Learners' Collaborative Behaviors in CSCL
Hsu, Jung-Lung; Chou, Huey-Wen; Hwang, Wu-Yuin; Chou, Shyan-Bin
2008-01-01
Computer supported collaborative learning (CSCL) has captured many educators and researchers to contribute their efforts on this domain. This study proposed a two-dimension concept to explain learners' collaboration behaviors in a CSCL laboratory setting. A two-dimension process, namely perceptual dimensions and supportive dimensions, is useful to…
Introduction to Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.; /SLAC
2010-04-29
Extra dimensions provide a very useful tool in addressing a number of the fundamental problems faced by the Standard Model. The following provides a very basic introduction to this very broad subject area as given at the VIII School of the Gravitational and Mathematical Physics Division of the Mexican Physical Society in December 2009. Some prospects for extra dimensional searches at the 7 TeV LHC with {approx}1 fb{sup -1} of integrated luminosity are provided.
DEFF Research Database (Denmark)
Wölfel, Christiane; Merritt, T.
2013-01-01
. The card-based tools are explained in terms of five design dimensions including the intended purpose and scope of use, duration of use, methodology, customization, and formal/material qualities. Our analysis suggests three design patterns or archetypes for existing card-based design method tools...... and highlights unexplored areas in the design space. The paper concludes with recommendations for the future development of card-based methods for the field of interaction design....
Bogdan Onete
2006-01-01
The quality of goods and services has always been a societal concern. The importance of quality was extended beyond physical products, to include services and information; and extended its reach into new arenas such as health care, education, or government. Organizations recognized the importance of focusing all of their activities on the customer and their requirements. New dimension of quality are performance, reliability, conformity, special characteristics and design.
Symmetry breaking: A heuristic approach to chaotic scattering in many dimensions
Benet, L.; Broch, J.; Merlo, O.; Seligman, T. H.
2005-03-01
As the theory of chaotic scattering in high-dimensional systems is poorly developed, it is very difficult to determine initial conditions for which interesting scattering events, such as long delay times, occur. We propose to use symmetry breaking as a way to gain the insight necessary to determine low-dimensional subspaces of initial conditions in which we can find such events easily. We study numerically the planar scattering off a disk moving on an elliptic Kepler orbit, as a simplified model of the elliptic restricted three-body problem. When the motion of the disk is circular, the system has an integral of motion, the Jacobi integral, which is no longer conserved for nonvanishing eccentricity. In the latter case, the system has an effective five-dimensional phase space and is therefore not amenable for study with the usual methods. Using the symmetric problem as a starting point we define an appropriate two-dimensional subspace of initial conditions by fixing some coordinates. This subspace proves to be useful to define scattering experiments where the rich and nontrivial dynamics of the problem is illustrated. We consider in particular trajectories which take very long before escaping or are trapped by consecutive collisions with the disk.
Identification of Sustainable Architecture Dimensions
Directory of Open Access Journals (Sweden)
Leila Etminan
2014-02-01
Full Text Available The main purpose in this research is identification of sustainable architecture dimensions. Nowadays, one of the most necessary complicated and main specifications of architecture with which architects are face is the issue of sustainability in various types of its interpretations. The issue of sustainability is interpretable and general according to many aspects. Therefore, it is necessary to identify this concept (architecture and its related categories. At the beginning of this discussion, we were faced with titles such as Green architecture2, Sustainable development3, etc. However, the purpose of this study is to study of nature and identify the circumstances and essence of sustainability in all fields in which the architecture is involved. The innovation of this study is to identify and feel the fact of sustainability dimensions that is studied in procedure of library research, a case sample and proposal of common but insufficient ideas related to this discussion. This study studies 3 approaches including main environmental, cultural (value and technical views and it tries to take the proposed topics under the subjection of this 3 factors respectively (presenting a modern model; furthermore, the minor factors are studied under the subjection of these 3 main factors.
Directory of Open Access Journals (Sweden)
Andy eClark
2013-05-01
Full Text Available An appreciation of the many roles of ‘precision-weighting’ (upping the gain on select populations of prediction error units opens the door to better accounts of planning and ‘offline simulation’, makes suggestive contact with large bodies of work on embodied and situated cognition, and offers new perspectives on the ‘active brain’. Combined with the complex affordances of language and culture, and operating against the essential backdrop of a variety of more biologically basic ploys and stratagems, the result is a maximally context-sensitive, restless, constantly self-reconfiguring architecture.
Bar dimensions and bar shapes in estuaries
Leuven, Jasper; Kleinhans, Maarten; Weisscher, Steven; van der Vegt, Maarten
2016-04-01
Estuaries cause fascinating patterns of dynamic channels and shoals. Intertidal sandbars are valuable habitats, whilst channels provide access to harbors. We still lack a full explanation and classification scheme for the shapes and dimensions of bar patterns in natural estuaries, in contrast with bars in rivers. Analytical physics-based models suggest that bar length in estuaries increases with flow velocity, tidal excursion length or estuary width, depending on which model. However, these hypotheses were never validated for lack of data and experiments. We present a large dataset and determine the controls on bar shape and dimensions in estuaries, spanning bar lengths from centimeters (experiments) to 10s of kilometers length. First, we visually identified and classified 190 bars, measured their dimensions (width, length, height) and local braiding index. Data on estuarine geometry and tidal characteristics were obtained from governmental databases and literature on case studies. We found that many complex bars can be seen as simple elongated bars partly cut by mutually evasive ebb- and flood-dominated channels. Data analysis shows that bar dimensions scale with estuary dimensions, in particular estuary width. Breaking up the complex bars in simple bars greatly reduced scatter. Analytical bar theory overpredicts bar dimensions by an order of magnitude in case of small estuarine systems. Likewise, braiding index depends on local width-to-depth ratio, as was previously found for river systems. Our results suggest that estuary dimensions determine the order of magnitude of bar dimensions, while tidal characteristics modify this. We will continue to model bars numerically and experimentally. Our dataset on tidal bars enables future studies on the sedimentary architecture of geologically complex tidal deposits and enables studying effects of man-induced perturbations such as dredging and dumping on bar and channel patterns and habitats.
Universality and Specificity of Fractal Dimension of Fractured Surfaces in Materials
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
After calculation on the fracture angles under various conditions of specific surface energies with different symmetry operations of rotation, the complicated behavior of dependence of fractal dimension on the structure of crystal is shown. It is found that the crack propagates along the weakest crystal plane no matter what the direction of the maximum stress is if the anisotropy is sufficiently strong; and then, the fractal dimension of the fractured surfaces might be determined by the approximate fractal structure already existed in the material. Specificity of the fractal dimension of fractured surfaces would be easy to appear in this case. Reversely, the crack propagates along the direction of the maximum stress no matter what direction of the weakest crystal plane is if the anisotropy is sufficiently weak. Universality of the fractal dimension of fractured surfaces would be possible to appear in this case. In many real materials, universality and specificity of the materials are associated. The fractal dimension measured may more or less be influenced by the structure of materials and it shows its universality through the specificity of materials.
L q dimensions and projections of random measures
Galicer, Daniel; Saglietti, Santiago; Shmerkin, Pablo; Yavicoli, Alexia
2016-09-01
We prove preservation of L q dimensions (for 1) under all orthogonal projections for a class of random measures on the plane, which includes (deterministic) homogeneous self-similar measures and a well-known family of measures supported on 1-variable fractals as special cases. We prove a similar result for certain convolutions, extending a result of Nazarov, Peres and Shmerkin. Recently many related results have been obtained for Hausdorff dimension, but much less is known for L q dimensions.
Jin, Shi; Roche, Kenneth; Wlazłowski, Gabriel
2016-01-01
Self-consistent approaches to superfluid many-fermion systems in 3-dimensions (and subsequent time-dependent approaches) require a large number of diagonalizations of very large dimension hermitian matrices, which results in enormous computational costs. We present an approach based on the shifted conjugate-orthogonal conjugate-gradient (COCG) method for the evaluation of the Green's function, from which we subsequently extract various densities (particle number, spin, current, kinetic energy, etc.) of a nuclear system needed in self-consistent approaches. The approach eschews the construction of the quasiparticle wavefunctions and their corresponding quasiparticle energies, which are never explicitly needed in any density functional approaches. As benchmarks we present calculations for nuclei with axial symmetry, including the ground state of spherical (magic or semi-magic) and axially deformed nuclei, the saddle-point in the $^{240}$Pu constrained fission path, and a vortex in the neutron star crust.
DEFF Research Database (Denmark)
Andersen, lotte bøgh; Beck Jørgensen, Torben; Kjeldsen, Anne-Mette;
2012-01-01
Further integration of the public value literature with other strands of literature within Public Administration necessitates a more specific classification of public values. This paper applies a typology linked to organizational design principles, because this is useful for empirical public...... administration studies. Based on an existing typology of modes of governance, we develop a classification and test it empirically, using survey data from a study of the values of 501 public managers. We distinguish between seven value dimensions (the public at large, rule abidance, societal interests, budget...... the integration between the public value literature and other parts of the Public Administration discipline....
Aspects of grand unification in higher dimensions
Energy Technology Data Exchange (ETDEWEB)
Wingerter, A.
2005-07-01
We consider various aspects of string phenomenology in the context of heterotic orbifold constructions, where special emphasis is laid on the connection between GUT models in extra dimensions and their relation to string theory. We investigate orbifold models with more general structure than the Z{sub 3} orbifold, on which most of the past research had focused. The picture of the heterotic brane world which naturally emerges allows us to make contact to field theoretic orbifold constructions in five and six dimensions, which have recently attracted much attention. We present a classification scheme for inequivalent orbifold models and apply the results to the case of Z{sub 6}-II point group. We develop the mathematical background for a stringy Higgs mechanism which allows us to lower the rank of the gauge group in the higher dimensions, which cannot be achieved by contemporary orbifold constructions. We provide all the calculational methods needed to unambiguously identify the gauge symmetry and to construct the matter representations. For specific model constructions, we focus on two promising gauge groups, namely on SO(10) and E{sub 6}. In the latter case, we derive a GUT model in six dimensions which has a standard model like gauge symmetry SU(3) x SU (2) x U(1) x U(1)' in four dimensions, and discuss its embedding into string theory. (orig.)
Aspects of grand unification in higher dimensions
International Nuclear Information System (INIS)
We consider various aspects of string phenomenology in the context of heterotic orbifold constructions, where special emphasis is laid on the connection between GUT models in extra dimensions and their relation to string theory. We investigate orbifold models with more general structure than the Z3 orbifold, on which most of the past research had focused. The picture of the heterotic brane world which naturally emerges allows us to make contact to field theoretic orbifold constructions in five and six dimensions, which have recently attracted much attention. We present a classification scheme for inequivalent orbifold models and apply the results to the case of Z6-II point group. We develop the mathematical background for a stringy Higgs mechanism which allows us to lower the rank of the gauge group in the higher dimensions, which cannot be achieved by contemporary orbifold constructions. We provide all the calculational methods needed to unambiguously identify the gauge symmetry and to construct the matter representations. For specific model constructions, we focus on two promising gauge groups, namely on SO(10) and E6. In the latter case, we derive a GUT model in six dimensions which has a standard model like gauge symmetry SU(3) x SU (2) x U(1) x U(1)' in four dimensions, and discuss its embedding into string theory. (orig.)
A Toy Model of Quantum Electrodynamics in (1 + 1) Dimensions
Boozer, A. D.
2008-01-01
We present a toy model of quantum electrodynamics (QED) in (1 + 1) dimensions. The QED model is much simpler than QED in (3 + 1) dimensions but exhibits many of the same physical phenomena, and serves as a pedagogical introduction to both QED and quantum field theory in general. We show how the QED model can be derived by quantizing a toy model of…
Directory of Open Access Journals (Sweden)
Chaitanya S. Mudgal
2014-03-01
greater knowledge, better skills and disseminate this knowledge through this journal to influence as many physicians and their patients as possible. They have taken the knowledge of their teachers, recognized their giants and are now poised to see further than ever before. My grandmother often used to quote to me a proverb from India, which when translated literally means “Many drops make a lake”. I cannot help but be amazed by the striking similarities between the words of Newton and this Indian saying. Therefore, while it may seem intuitive, I think it must be stated that it is vital for the betterment of all our patients that we recognize our own personal lakes to put our drops of knowledge into. More important is that we recognize that it is incumbent upon each and every one of us to contribute to our collective lakes of knowledge such as ABJS. And finally and perhaps most importantly we need to be utterly cognizant of never letting such lakes of knowledge run dry.... ever.
The many faces of testosterone
Directory of Open Access Journals (Sweden)
Jerald Bain
2007-01-01
Full Text Available Jerald BainDepartment of Medicine, Department of Obstetrics and Gynecology, University of Toronto, Ontario, Canada; Division of Endocrinology and Metabolism, Mount Sinai Hospital, Toronto, Ontario, CanadaAbstract: Testosterone is more than a “male sex hormone”. It is an important contributor to the robust metabolic functioning of multiple bodily systems. The abuse of anabolic steroids by athletes over the years has been one of the major detractors from the investigation and treatment of clinical states that could be caused by or related to male hypogonadism. The unwarranted fear that testosterone therapy would induce prostate cancer has also deterred physicians form pursuing more aggressively the possibility of hypogonadism in symptomatic male patients. In addition to these two mythologies, many physicians believe that testosterone is bad for the male heart. The classical anabolic agents, 17-alkylated steroids, are, indeed, potentially harmful to the liver, to insulin action to lipid metabolism. These substances, however, are not testosterone, which has none of these adverse effects. The current evidence, in fact, strongly suggests that testosterone may be cardioprotective. There is virtually no evidence to implicate testosterone as a cause of prostate cancer. It may exacerbate an existing prostate cancer, although the evidence is flimsy, but it does not likely cause the cancer in the first place. Testosterone has stimulatory effects on bones, muscles, erythropoietin, libido, mood and cognition centres in the brain, penile erection. It is reduced in metabolic syndrome and diabetes and therapy with testosterone in these conditions may provide amelioration by lowering LDL cholesterol, blood sugar, glycated hemoglobin and insulin resistance. The best measure is bio-available testosterone which is the fraction of testosterone not bound to sex hormone binding globulin. Several forms of testosterone administration are available making compliance
The many faces of testosterone
Directory of Open Access Journals (Sweden)
Jerald Bain
2008-01-01
Full Text Available Jerald BainDepartment of Medicine, Department of Obstetrics and Gynecology, University of Toronto, Ontario, Canada; Division of Endocrinology and Metabolism, Mount Sinai Hospital, Toronto, Ontario, CanadaAbstract: Testosterone is more than a “male sex hormone”. It is an important contributor to the robust metabolic functioning of multiple bodily systems. The abuse of anabolic steroids by athletes over the years has been one of the major detractors from the investigation and treatment of clinical states that could be caused by or related to male hypogonadism. The unwarranted fear that testosterone therapy would induce prostate cancer has also deterred physicians form pursuing more aggressively the possibility of hypogonadism in symptomatic male patients. In addition to these two mythologies, many physicians believe that testosterone is bad for the male heart. The classical anabolic agents, 17-alkylated steroids, are, indeed, potentially harmful to the liver, to insulin action to lipid metabolism. These substances, however, are not testosterone, which has none of these adverse effects. The current evidence, in fact, strongly suggests that testosterone may be cardioprotective. There is virtually no evidence to implicate testosterone as a cause of prostate cancer. It may exacerbate an existing prostate cancer, although the evidence is flimsy, but it does not likely cause the cancer in the first place. Testosterone has stimulatory effects on bones, muscles, erythropoietin, libido, mood and cognition centres in the brain, penile erection. It is reduced in metabolic syndrome and diabetes and therapy with testosterone in these conditions may provide amelioration by lowering LDL cholesterol, blood sugar, glycated hemoglobin and insulin resistance. The best measure is bio-available testosterone which is the fraction of testosterone not bound to sex hormone binding globulin. Several forms of testosterone administration are available making compliance
Adjoint Functors and Representation Dimensions
Institute of Scientific and Technical Information of China (English)
Chang Chang XI
2006-01-01
We study the global dimensions of the coherent functors over two categories that are linked by a pair of adjoint functors. This idea is then exploited to compare the representation dimensions of two algebras. In particular, we show that if an Artin algebra is switched from the other, then they have the same representation dimension.
Self-forces on static bodies in arbitrary dimensions
Harte, Abraham I; Taylor, Peter
2016-01-01
We derive exact expressions for the scalar and electromagnetic self-forces and self-torques acting on arbitrary static extended bodies in arbitrary static spacetimes with any number of dimensions. Non-perturbatively, our results are identical in all dimensions. Meaningful point particle limits are quite different in different dimensions, however. These limits are defined and evaluated, resulting in simple "regularization algorithms" which can be used in concrete calculations. In these limits, self-interaction is shown to be progressively less important in higher numbers of dimensions; it generically competes in magnitude with increasingly high-order extended-body effects. Conversely, we show that self-interaction effects can be relatively large in $1+1$ and $2+1$ dimensions. Our motivations for this work are twofold: First, no previous derivation of the self-force has been provided in arbitrary dimensions, and heuristic arguments presented by different authors have resulted in conflicting conclusions. Second,...
Dental Arch Dimension of Malay Ethnic Group
Directory of Open Access Journals (Sweden)
H. A. Mohammad
2011-01-01
Full Text Available Problem statement: Many previous studies tried to define and put specific measurements for dental arches dimension in different ethnics groups. However, these studies may be specific to an ethnic group and cannot always be applied to other ethnic types. The aim of this study: is to obtain specific dental arch dimensions for Malaysian Malay ethnic groups and compare between both genders. Approach: Involved clinical examination, collection and analysis of 60 dental cast of Malaysian Malay subjects from pure ethnic group (30 males and 30 females, 20-24 years old. All dental landmarks were located and determined and subsequently measurements had been done according to specific points have been selected. Statistical analysis were done using t-test. Results: Dental arch dimension were established in normal occlusion for Malaysian Malay ethnic group in this study. No significant difference was observed in arch dimensions between male and female of Malaysian Malay. Conclusion: These measurement should be considered during treatment, especially in prosthodontics and orthodontics where arch dimension can be modified appreciably.
The Hausdorff dimension in polymerized quantum gravity
Harris, M G; Harris, Martin G.; Wheater, John F.
1999-01-01
We calculate the Hausdorff dimension, $d_H$, and the correlation function exponent, $\\eta$, for polymerized two dimensional quantum gravity models. If the non-polymerized model has correlation function exponent $\\eta_0 >3$ then $d_H=\\gamma^{-1}$ where $\\gamma$ is the susceptibility exponent. This suggests that these models may be in the same universality class as certain non-generic branched polymer models.
The Cultural Dimensions of Language Teaching and Learning
DEFF Research Database (Denmark)
Risager, Karen
2011-01-01
and presented in class. The next dimension was that of the learner: the (inter)cultural learning, competence and identity of the learner or subject. The next dimension was context: the situation and role of language teaching and learning in society and in the world.......Language teaching and learning has many different cultural dimensions, and over the years more and more of these have been the subject of research. The first dimension to be explored was that of content: the images of target language countries and the world that were offered in textbooks...
Some Dimensions of Spaces of Finite Type Invariants of Virtual Knots
Bar-Natan, Dror; Leung, Louis; Roukema, Fionntan
2009-01-01
We compute many dimensions of spaces of finite type invariants of virtual knots (of several kinds) and the dimensions of the corresponding spaces of "weight systems", finding everything to be in agreement with the conjecture that "every weight system integrates".
Dehn Filling and Einstein Metrics in Higher Dimensions
Anderson, Michael T.
2006-01-01
We prove that many features of Thurston's Dehn surgery theory for hyperbolic 3-manifolds generalize to Einstein metrics in any dimension. In particular, this gives large, infinite families of new Einstein metrics on compact manifolds.
Nonlinear models in 2 + epsilon dimensions
International Nuclear Information System (INIS)
The general nonlinear scalar model is studied at asymptotically low temperature near two dimensions. The low-temperature expansion is renormalized, and effective algorithms are derived for calculation to all orders in the renormalized expansion. The renormalization group coefficients are calculated in the two-loop approximation, and topological properties of the renormalization group equations are investigated. Special attention is paid to the infrared instabilities of the fixed points, since they provide the continuum limits of the model. The model consists of a scalar field phi on Euclidean 2 + epsilon space whose values phi(x) lie in a finite-dimensional differentiable manifold. 4 figures
Dimension Driven Accelerating Universe
Chatterjee, S
2009-01-01
The current acceleration of the universe leads us to investigate higher dimensional gravity theory, which is able to explain acceleration from a theoretical view point without the need of introducing dark energy by hand. We argue that the terms containing higher dimensional metric coefficients produce an extra negative pressure that apparently drives an acceleration of the 3D space, tempting us to suggest that the accelerating universe seems to act as a window to the existence of extra spatial dimensions. Interesting to point out that in this case our cosmology apparently mimics the well known quintessence scenario fuelled by a generalised Chaplygin-type of fluid where a smooth transition from a dust dominated model to a de Sitter like one takes place. Correspondence to models generated by a tachyonic form of matter is also briefly discussed.
DEFF Research Database (Denmark)
Frederiksen, Morten
2012-01-01
Georg Simmel is the seminal author on trust within sociology, but though inspired by Simmel, subsequent studies of intersubjective trust have failed to address Simmel’s suggestion that trust is as differentiated as the social relations of which it is part. Rather, trust has been studied within...... limited sets of exchange or work relations. This article revisits Simmel’s concept of trust as social form in order to investigate this differentiation. From an interview study, the differentiation and limits of trust are analysed within different types of social relations. Trust is found to vary greatly...... in scope and mode influenced by the intersecting dimensions of relations, objects and situations. Furthermore, trust exists between an outer threshold of expected deceit and an inner threshold of confident reliance. The findings from the qualitative study contribute new knowledge on the diversity of trust...
Schweitzer, Eugen
2009-01-01
In different passages of his dialogues, Plato showed deep mathematically-based physical insights. Regrettably most readers overlooked the respective statements, or they utterly did not understand those hints since they were full of philological fallacious terms. Respectable translators misinterpreted such statements and therefore Plato's respective remarks were not recognized as substantial knowledge. Furthermore, Plato often supplemented such basic remarks by diffusely veiled and varied allusions that were often ironically hidden somewhere in his dialogues by inconspicuous double meanings. However, this mode of intentionally coded discrete communication was generally not understood because such irony is not to everyone's taste. However, the attempts to reconstruct Plato's system on the basis of admittedly individually interpreted double meanings lead to a conclusive mathematical-physical cyclical system of dimensions. Additionally it was possible to assign Plato's system of philosophical ideas analogously to...
Jackson, David J
2016-01-01
A physical theory of the world is presented under the unifying principle that all of nature is laid out before us and experienced through the passage of time. The one-dimensional progression in time is opened out into a multi-dimensional mathematically consistent flow, with the simplicity of the former giving rise to symmetries of the latter. The act of perception identifies an extended spacetime arena of intermediate dimension, incorporating the symmetry of geometric spatial rotations, against which physical objects are formed and observed. The spacetime symmetry is contained as a subgroup of, and provides a natural breaking mechanism for, the higher general symmetry of time. It will be described how the world of gravitation and cosmology, as well as quantum theory and particle physics, arises from these considerations.
Lévay, Péter
2011-01-01
We link the recently discovered black hole-qubit correspondence to the structure of extra dimensions. In particular we show that for toroidal compactifications of type IIB string theory simple qubit systems arise naturally from the geometrical data of the tori parametrized by the moduli. We also generalize the recently suggested idea of the attractor mechanism as a distillation procedure of GHZ-like entangled states on the event horizon, to moduli stabilization for flux attractors in F-theory compactifications on elliptically fibered Calabi-Yau four-folds. Finally using a simple example we show that the natural arena for qubits to show up is an embedded one within the realm of fermionic entanglement of quantum systems with indistinguishable constituents.
Infinitely many singular interactions on Cartan-Hadamard manifolds
Kaynak, Burak Tevfik
2014-01-01
We show that the ground state energy is bounded from below when there are infinitely many attractive delta function potentials placed in arbitrary locations, while being separated by a minimum distance, on a Cartan-Hadamard manifold in two dimensions. For this purpose, we employ the heat kernel techniques as well as some comparison theorems of Riemannian geometry, thus generalizing the arguments in the flat case following the approach presented in Albeverio et. al.
Quantum Physics in One Dimension
Energy Technology Data Exchange (ETDEWEB)
Logan, David [University of Oxford (United Kingdom)
2004-05-14
To a casual ostrich the world of quantum physics in one dimension may sound a little one-dimensional, suitable perhaps for those with an unhealthy obsession for the esoteric. Nothing of course could be further from the truth. The field is remarkably rich and broad, and for more than fifty years has thrown up innumerable challenges. Theorists, realising that the role of interactions in 1D is special and that well known paradigms of higher dimensions (Fermi liquid theory for example) no longer apply, took up the challenge of developing new concepts and techniques to understand the undoubted peculiarities of one-dimensional systems. And experimentalists have succeeded in turning pipe dreams into reality, producing an impressive and ever increasing array of experimental realizations of 1D systems, from the molecular to the mesoscopic - spin and ladder compounds, organic superconductors, carbon nanotubes, quantum wires, Josephson junction arrays and so on. Many books on the theory of one-dimensional systems are however written by experts for experts, and tend as such to leave the non-specialist a touch bewildered. This is understandable on both fronts, for the underlying theoretical techniques are unquestionably sophisticated and not usually part of standard courses in many-body theory. A brave author it is then who aims to produce a well rounded, if necessarily partial, overview of quantum physics in one dimension, accessible to a beginner yet taking them to the edge of current research, and providing en route a thorough grounding in the fundamental ideas, basic methods and essential phenomenology of the field. It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated. Aimed in particular at graduate students in theoretical condensed matter physics, and assuming little theoretical background on the part of the reader (well just a little), Giamarchi writes in a
Multiorder boundaries among discrete domains: relative fractal dimension and others.
Xuan, Qi; Du, Fang; Wu, Tie-Jun
2010-03-01
In nature and society, most of competitions take place on the boundaries among a group of domains where different individuals or colonies share common resources; therefore, it is widely believed that domain boundaries play important roles in the evolution of many complex systems. Here, we first give a definition for multiorder boundaries among discrete domains and then propose a general method to calculate their relative fractal dimension, i.e., the ratio of the fractal dimension of the boundaries versus that of the domains themselves. Through analyzing three types of real-world discrete domains, several interesting results are revealed. For example, the limitation on the number of domains that an individual can join in may produce longer boundaries indicating more cruel competitions among the domains. Besides, the individuals with more social links are always considered more important in social networks, and it is found that these individuals as valuable resources of social domains are always centralized on the boundaries of higher order. PMID:20370288
Higher degree moment tensor inversion of Mani earthquake using far-field broad- band recording
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Breakthrough point source model, extended earthquake source model is used to calculate more seismic source parameters in this paper. We express seismic source using higher degree moment tensors, to reduce a large number terms originally presenting in higher degree moment tensor representation, Haskell rupture model is used. We inverted the source parameters of Mani earthquake in Tibet using broad-band body wave of 32 stations of Global Seismograph Network (GSN), the results show that it is a strike-slip fault, rupture direction is 75° , rupture duration is 19 s, the fault plan is f =77° , d =88° , l =0° , the auxiliary plane is f =347° , d =90° , l =178° , and the fault dimension is 47 km′ 28 km. These results will give new quantitative data for earth dynamics and have practical meaning for seismic source tomography research.
Synthesis of Mechanisms using Time-Varying Dimensions
DEFF Research Database (Denmark)
Hansen, John Michael
2002-01-01
Many methods of performing mechanism synthesis rely on an attempt to redefine the dimensions of the system in such a way that a deviation from the desired behavior is minimized by the use of optimization methods. During the optimization process the optimizer may, however, suggest values of the di......Many methods of performing mechanism synthesis rely on an attempt to redefine the dimensions of the system in such a way that a deviation from the desired behavior is minimized by the use of optimization methods. During the optimization process the optimizer may, however, suggest values...... of the dimensions, or design variables, that lead to infeasible designs, i.e. dimensions for which the mechanism cannot be assembled in one or more positions. With the method proposed her, this problem is overcome by allowing the dimensions to vary during the motion of the system and subsequently minimizing...
Interactive Dimensioning of Parametric Models
Kelly, T.
2015-05-01
We propose a solution for the dimensioning of parametric and procedural models. Dimensioning has long been a staple of technical drawings, and we present the first solution for interactive dimensioning: A dimension line positioning system that adapts to the view direction, given behavioral properties. After proposing a set of design principles for interactive dimensioning, we describe our solution consisting of the following major components. First, we describe how an author can specify the desired interactive behavior of a dimension line. Second, we propose a novel algorithm to place dimension lines at interactive speeds. Third, we introduce multiple extensions, including chained dimension lines, controls for different parameter types (e.g. discrete choices, angles), and the use of dimension lines for interactive editing. Our results show the use of dimension lines in an interactive parametric modeling environment for architectural, botanical, and mechanical models. © 2015 The Author(s) Computer Graphics Forum © 2015 The Eurographics Association and John Wiley & Sons Ltd. Published by John Wiley & Sons Ltd.
Many-body approaches to nuclear physics
Energy Technology Data Exchange (ETDEWEB)
Hjorth-Jensen, M.
1993-10-01
This thesis deals with applications of perturbative many-body theories to selected nuclear systems at low and intermediate energies. Examples are the properties of neutron stars, the calculation of shell-model effective interactions and the microscopic derivation of the optical-model potential for finite nuclei. The line of research leans on the microscopic approach, i.e. an approach which aims at describing nuclear properties from the underlying free interaction between the various hadrons where parameters like meson coupling constants define the Lagrangians. The emphasis is on the behavior of the various components of the free interaction in different nuclear media in order to understand how these components are affected by the studied nuclear correlations. 159 refs.
Exponentially Slow Heating in Periodically Driven Many-Body Systems.
Abanin, Dmitry A; De Roeck, Wojciech; Huveneers, François
2015-12-18
We derive general bounds on the linear response energy absorption rates of periodically driven many-body systems of spins or fermions on a lattice. We show that, for systems with local interactions, the energy absorption rate decays exponentially as a function of driving frequency in any number of spatial dimensions. These results imply that topological many-body states in periodically driven systems, although generally metastable, can have very long lifetimes. We discuss applications to other problems, including the decay of highly energetic excitations in cold atomic and solid-state systems. PMID:26722939
Codes and Supersymmetry in One Dimension
Doran, C F; Gates, S J; Hübsch, T; Iga, K M; Landweber, G D; Miller, R L
2011-01-01
Adinkras are diagrams that describe many useful supermultiplets in D=1 dimensions. We show that the topology of the Adinkra is uniquely determined by a doubly even code. Conversely, every doubly even code produces a possible topology of an Adinkra. A computation of doubly even codes results in an enumeration of these Adinkra topologies up to N=28, and for minimal supermultiplets, up to N=32.
A Survey of Dimension Reduction Techniques
Energy Technology Data Exchange (ETDEWEB)
Fodor, I K
2002-05-09
Advances in data collection and storage capabilities during the past decades have led to an information overload in most sciences. Researchers working in domains as diverse as engineering, astronomy, biology, remote sensing, economics, and consumer transactions, face larger and larger observations and simulations on a daily basis. Such datasets, in contrast with smaller, more traditional datasets that have been studied extensively in the past, present new challenges in data analysis. Traditional statistical methods break down partly because of the increase in the number of observations, but mostly because of the increase in the number of variables associated with each observation. The dimension of the data, is the number of variables that are measured on each observation. High-dimensional datasets present many mathematical challenges as well as some opportunities, and are bound to give rise to new theoretical developments. One of the problems with high-dimensional datasets is that, in many cases, not all the measured variables are ''important'' for understanding the underlying phenomena of interest. While certain computationally expensive novel methods can construct predictive models with high accuracy from high-dimensional data, it is still of interest in many applications to reduce the dimension of the original data prior to any modeling of the data. In this paper, we described several dimension reduction methods.
Upper bounds for the essential dimension of the moduli stack of ${\\sl_{n}}$-bundles over a curve
Dhillon, Ajneet; Lemire, Nicole
2009-01-01
We find upper bounds for the essential dimension of various moduli stacks of $\\sln$-bundles over a curve. When $n$ is a prime power, our calculation computes the essential dimension of the stack of stable bundles exactly and the essential dimension is not equal to the dimension in this case.
Thermal dimension of quantum spacetime
Amelino-Camelia, Giovanni; Gubitosi, Giulia; Santos, Grasiele
2016-01-01
Recent results suggest that a crucial crossroad for quantum gravity is the characterization of the effective dimension of spacetime at short distances, where quantum properties of spacetime become significant. This is relevant in particular for various scenarios of "dynamical dimensional reduction" which have been discussed in the literature. We are here concerned with the fact that the related research effort has been based exclusively on analyses of the "spectral dimension", which involves an unphysical Euclideanization of spacetime and is highly sensitive to the off-shell properties of a theory. As here shown, different formulations of the same physical theory can have wildly different spectral dimension. We propose that dynamical dimensional reduction should be described in terms of the "thermal dimension" which we here introduce, a notion that only depends on the physical content of the theory. We analyze a few models with dynamical reduction both of the spectral dimension and of our thermal dimension, f...
Prediction and calculation for new energy development
Institute of Scientific and Technical Information of China (English)
Fu Yuhua; Fu Anjie
2008-01-01
Some important questions for new energy development were discussed, such as the prediction and calculation of sea surface temperature, ocean wave, offshore platform price, typhoon track, fn'e status, vibration due to earth-quake, energy price, stock market's trend and so on with the fractal methods ( including the four ones of constant di-mension fractal, variable dimension fractal, complex number dimension fractal and fractal series) and the improved res-caled range analysis (R/S analysis).
Prakash, Manu
2011-01-01
Diversity and specialization of behavior in insects is unmatched. Insects hop, walk, run, jump, row, swim, glide and fly to propel themselves in a variety of environments. We have uncovered an unusual mode of propulsion of aerodynamic flight in two dimensions in Waterlilly Beetles \\emph{(Galerucella)}. The adult beetles, often found in water lilly ponds, propel themselves strictly in a two-dimensional plane on the surface of water via flapping wing flight. Here we analyze the aerodynamics of this peculiar flight mode with respect to forces exerted on the organism during flight. The complexity of 2-D flight is captured by accounting for additional forces beyond gravitational, thrust, lift and drag, exerted on the insect body in 3D flight. Understanding this constrained propulsion mode requires accounting for viscous drag, surface tension, buoyancy force, and capillary-wave drag. Moreover, dramatic differences exist in the magnitude of the resultant forces in 2D vs. 3D flight. Here, in this fluid dynamics video...
Pauli Spin Paramagnetism and Electronic Specific Heat in Generalised d-Dimensions
Institute of Scientific and Technical Information of China (English)
Muktish Acharyya
2011-01-01
The variations of pauli spin paramagnetic susceptibility and the electronic specific heat of solids, are calculated as functions of temperature following the free electron approximation, in generalised d-dimensions.The results are compared and become consistent with that obtained in three dimensions.Interestingly, the Pauli spin paramagnetic susceptibility becomes independent of temperature only in two dimensions.
Variational Study of Fermionic Helium Dimer and Trimer in Two Dimensions
Vranješ, Leandra; Kilić, Srećko
2000-01-01
In variational calculation, we have obtained the binding energy of helium 3 dimer in two dimensions. The existence of one bound State, with the binding energy -0.014 mK, has been definitively found. Also, the existence of a binding state of helium 3 trimer having spin -1/2 with the energy below -0.0057 mK is indicated. This re-opens the question of the existence of the gas phase of many helium 3 atoms on the surface of superfluid helium 4.
Hilbert space renormalization for the many-electron problem
Li, Zhendong
2015-01-01
Renormalization is a powerful concept in the many-body problem. Inspired by the highly successful density matrix renormalization group (DMRG) algorithm, and the quantum chemical graphical representation of configuration space, we introduce a new theoretical tool: Hilbert space renormalization, to describe many-electron correlations. While in DMRG, the many-body states in nested Fock subspaces are successively renormalized, in Hilbert space renormalization, many-body states in nested Hilbert subspaces undergo renormalization. This provides a new way to classify and combine configurations. The underlying wavefunction ansatz, namely the Hilbert space matrix product state (HS-MPS), has a very rich and flexible mathematical structure. It provides low-rank tensor approximations to any configuration interaction (CI) space through restricting either the 'physical indices' or the coupling rules in the HS-MPS. Alternatively, simply truncating the 'virtual dimension' of the HS-MPS leads to a family of size-extensive wav...
Dimensions of Drug Information
Sharp, Mark E.
2011-01-01
The high number, heterogeneity, and inadequate integration of drug information resources constitute barriers to many drug information usage scenarios. In the biomedical domain there is a rich legacy of knowledge representation in ontology-like structures that allows us to connect this problem both to the very mature field of library and…
Institute of Scientific and Technical Information of China (English)
ZHU Xiao-hua; CAI Yun-long
2004-01-01
MANDELBROT enunciated the uncertainty of the length of a coastline in his paper "How long is the coastline of Britain?" published in Science in 1967. The fractal concept was presented for the first time in that paper and has been applied to many fields ever since. Although fractal dimensions of lots of phenomena were calculated by the box-counting method, the quantitative influence of series of square grids on them is ignored. The issue is systematically discussed as a case study of the mountains of China's Mainland in this paper. And some significant conclusions are drawn as follows: 1) Although the fractal character objectively exists in the mountains of China's Mainland, and it does not vary with the changes of series of square grids, the fractal dimensions of the mountains of China's Mainland are different with these changes. 2) The fractal dimensions of the mountains of China's Mainland vary with the average lengths of sides of series of square grids. The fractal dimension of the mountains of China's Mainland is the function of the average length of side of square grid. They conform to the formula D=f(r) (where D is the fractal dimension, and r is the average length of side of square grid). 3) Different dots of data collection can affect the fractal dimension of the mountains of China's Mainland. 4) The same range of length of side of square grid and dots of data collection can ensure the comparison of fractal dimensions of the mountains of China's Mainland. The research is helpful to get the more understanding of fractai and fractal dimension, and ensure that the fractal studies would be scientific.
Collider Implications Of Extra Dimensions At Lhc
Reema
2005-01-01
Scope and method of study. The intent of this research is to consider multiple TeV-1-size extra compact dimensions in an asymmetric string compactification scenario in which the SM gauge bosons can propagate into the TeV-1-size extra dimensions while the SM fermions are confined to the usual SM D3-brane. The contributions that the KK excitations of the gluons, g*'s, make to the multijet cross sections in proton- proton collisions at the LHC energy are calculated. Fortran was used to do the calculations. Findings and conclusions. At very high pT, the dijet signal will either be enhanced significantly due to virtual g* exchanges or place a lower bound on the compactification scale of about 8 TeV. It is found that the dijet signal is very sensitive to three parameters—the compactification scale, the string scale, and the number of extra dimensions. Thus, although the dijet signal is much more sensitive to KK effects, the dijet signal alone does not provide sufficient information to deduce the number of...
Scale dimension as the fifth dimension of spacetime
FEDOSIN, Sergey
2012-01-01
The scale dimension discovered in the theory of infinite nesting of matter is studied from the perspective of physical implementation of well-studied four-and n-dimensional geometric objects. Adding the scale dimension to Minkowski four-dimensional space means the necessity to use the five-dimensional spacetime.
Warped Geometry in Higher Dimensions with an Orbifold Extra Dimension
Ito, M
2001-01-01
We solve the Einstein equations in higher dimensions with warped geometry where an extra dimension is assumed to have orbifold symmetry, $S^{1}/Z_{2}$. The setup we consider here is an extension to (5+D)-dimensions of the 5-dimensional Randall-Sundrum model, and two hidden brane and observable brane are fixed on orbifold. Anisotropic cosmological constant on each brane with (4+D)-dimensional spacetime is assumed, and the warped metric of 4-dimensions is generally different from one of extra D-dimensions. It is pointed out that the form of metric depends on both the sign of bulk cosmological constant and initial condition of brane world. Furthermore, anisotropic cosmological constant on each brane can be realized due to the presence of brane.
Vitali, Ettore; Shi, Hao; Qin, Mingpu; Zhang, Shiwei
2016-08-01
We address the calculation of dynamical correlation functions for many fermion systems at zero temperature, using the auxiliary-field quantum Monte Carlo method. The two-dimensional Hubbard hamiltonian is used as a model system. Although most of the calculations performed here are for cases where the sign problem is absent, the discussions are kept general for applications to physical problems when the sign problem does arise. We study the use of twisted boundary conditions to improve the extrapolation of the results to the thermodynamic limit. A strategy is proposed to drastically reduce finite size effects relying on a minimization among the twist angles. This approach is demonstrated by computing the charge gap at half filling. We obtain accurate results showing the scaling of the gap with the interaction strength U in two dimensions, connecting to the scaling of the unrestricted Hartree-Fock method at small U and Bethe ansatz exact result in one dimension at large U . An alternative algorithm is then proposed to compute dynamical Green functions and correlation functions which explicitly varies the number of particles during the random walks in the manifold of Slater determinants. In dilute systems, such as ultracold Fermi gases, this algorithm enables calculations with much more favorable complexity, with computational cost proportional to basis size or the number of lattice sites.
O(n) tricriticality in two dimensions
Institute of Scientific and Technical Information of China (English)
GUO Wen-an; Henk W. J. Bl(o)te; Bernard Nienhuis
2007-01-01
We present exact results for several universal parameters of the tricritical O (n) model in two dimensions. The results apply to the range -2≤n≤3/2, and include the central charge and three scaling dimensions, associated with temperature, magnetic field and the introduction of an interface. Since these results are based on an extrapolation of known relations between the O (n) and the Potts model, they cannot be considered as rigorous. For this reason, we perform an accurate numerical analysis of the central charge and the critical exponents. This analysis, which is based on transfer-matrix calculations on the honeycomb lattice, is in a full and precise agreement with the theoretical predictions.
Beta Function and Anomalous Dimensions
DEFF Research Database (Denmark)
Pica, Claudio; Sannino, Francesco
2011-01-01
We demonstrate that it is possible to determine the coefficients of an all-order beta function linear in the anomalous dimensions using as data the two-loop coefficients together with the first one of the anomalous dimensions which are universal. The beta function allows to determine the anomalous...
Dimensioning, Tolerancing, and Machine Finishes.
Adams, George C.
Intended for use with the vocational education student interested in technical drawing, this guide provides answers to questions relating to dimensioning and tolerancing machine drawings. It also gives examples of standard dimensioning practices, tolerancing applications, and finish applications. The problems and examples presented are based on…
Quantum scattering in one dimension
Energy Technology Data Exchange (ETDEWEB)
Barlette, Vania E. [Centro Universitario Franciscano, Santa Maria, RS (Brazil); Leite, Marcelo M. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP (Brazil); Adhikari, Sadhan K. [Instituto de Fisica Teorica, Universidade Estadual Paulista, Sao Paulo, SP (Brazil)
2000-09-01
A self-contained discussion of non-relativistic quantum scattering is presented in the case of central potentials in one space dimension, which will facilitate the understanding of the more complex scattering theory in two and three dimensions. The present discussion illustrates in a simple way the concepts of partial-wave decomposition, phase shift, optical theorem and effective-range expansion. (author)
Dimensions of Organizational Task Environments.
Dess, Gregory G.; Beard, Donald W.
1984-01-01
Reducing Aldrich's codification of organizational task environments from six to three dimensions--munificence (capacity), complexity (homogeneity-heterogeneity, concentration-dispersion), and dynamism (stability-instability, turbulence), the authors use interim and factor analytical techniques to explore each dimension's viability and draw…
Casimir Forces due to Matters in Compactified Six Dimensions
Ito, M
2003-01-01
We calculate the Casimir energies due to matters with various boundary conditions along two compact directions in six-dimensional $T^{2}$ compactification. We discuss whether the Casimir forces are attractive or repulsive forces. On the theories with extra dimensions, the Casimir energy plays a crucial role in the mechanism for stabilizing the size of extra dimensions. Finally we argue a procedure of the application to $Z_{2}$ orbifold.
Dynamic Demonstration of Ceramic Grain Growth in Three Dimensions
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
Microstructural evolutions of ceramic grain growth we re dynamically demonstrated with 3D graphical display techniques. Based on the p rinciples of grain growth in ceramics, the data of coordination in different ato ms were calculated with Monte-Carlo method at atomistic scale. Realistic images in three-dimension were displayed onto two-dimension monitor by projection, i llumination and atomization, using Visual C++ and OpenGL languages. Different small spheres were used to model different kind of atoms,...
The Fractal Dimensions of Complex Networks
Institute of Scientific and Technical Information of China (English)
GUO Long; CAI Xu
2009-01-01
It is shown that many real complex networks share distinctive features,such as the small-world effect and the heterogeneous property of connectivity of vertices,which are different from random networks and regular lattices.Although these features capture the important characteristics of complex networks,their applicability depends on the style of networks.To unravel the universal characteristics many complex networks have in common,we study the fractal dimensions of complex networks using the method introduced by Shanker.We lind that the average 'density' (p(r)) of complex networks follows a better power-law function as a function of distance r with the exponent df,which is defined as the fractal dimension,in some real complex networks.Furthermore,we study the relation between df and the shortcuts Nadd in small-world networks and the size N in regular lattices.Our present work provides a new perspective to understand the dependence of the fractal dimension df on the complex network structure.
SRD 166 MEMS Calculator (Web, free access) This MEMS Calculator determines the following thin film properties from data taken with an optical interferometer or comparable instrument: a) residual strain from fixed-fixed beams, b) strain gradient from cantilevers, c) step heights or thicknesses from step-height test structures, and d) in-plane lengths or deflections. Then, residual stress and stress gradient calculations can be made after an optical vibrometer or comparable instrument is used to obtain Young's modulus from resonating cantilevers or fixed-fixed beams. In addition, wafer bond strength is determined from micro-chevron test structures using a material test machine.
Transfer Area Mechanical Handling Calculation
Energy Technology Data Exchange (ETDEWEB)
B. Dianda
2004-06-23
This calculation is intended to support the License Application (LA) submittal of December 2004, in accordance with the directive given by DOE correspondence received on the 27th of January 2004 entitled: ''Authorization for Bechtel SAX Company L.L. C. to Include a Bare Fuel Handling Facility and Increased Aging Capacity in the License Application, Contract Number DE-AC28-01R W12101'' (Arthur, W.J., I11 2004). This correspondence was appended by further Correspondence received on the 19th of February 2004 entitled: ''Technical Direction to Bechtel SAIC Company L.L. C. for Surface Facility Improvements, Contract Number DE-AC28-OIRW12101; TDL No. 04-024'' (BSC 2004a). These documents give the authorization for a Fuel Handling Facility to be included in the baseline. The purpose of this calculation is to establish preliminary bounding equipment envelopes and weights for the Fuel Handling Facility (FHF) transfer areas equipment. This calculation provides preliminary information only to support development of facility layouts and preliminary load calculations. The limitations of this preliminary calculation lie within the assumptions of section 5 , as this calculation is part of an evolutionary design process. It is intended that this calculation is superseded as the design advances to reflect information necessary to support License Application. The design choices outlined within this calculation represent a demonstration of feasibility and may or may not be included in the completed design. This calculation provides preliminary weight, dimensional envelope, and equipment position in building for the purposes of defining interface variables. This calculation identifies and sizes major equipment and assemblies that dictate overall equipment dimensions and facility interfaces. Sizing of components is based on the selection of commercially available products, where applicable. This is not a specific recommendation for the future use
Fractal Dimension Of CT Images Of Normal Parotid Glands
International Nuclear Information System (INIS)
This study was to investigate the age and sex differences of the fractal dimension of the normal parotid glands in the digitized CT images. The six groups, which were composed of 42 men and women from 20's, 40's and 60's and over were picked. Each group contained seven people of the same sex. The normal parotid CT images were digitized, and their fractal dimensions were calculated using Scion Image PC program. The mean of fractal dimensions in males was 1.7292 (+/-0.0588) and 1.6329 (+/-0.0425) in females. The mean of fractal dimensions in young males was 1.7617, 1.7328 in middle males, and 1.6933 in old males. The mean of fractal dimensions in young females was 1.6318, 1.6365 in middle females, and 1.6303 in old females. There was no statistical difference in fractal dimension between left and right parotid gland of the same subject (p>0.05). Fractal dimensions in male were decreased in older group (p0.05). The fractal dimension of parotid glands in the digitized CT images will be useful to evaluate the age and sex differences.
DEFF Research Database (Denmark)
Petersen, Kurt Erling
1986-01-01
approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very...... complex systems. In order to increase the applicability of the programs variance reduction techniques can be applied to speed up the calculation process. Variance reduction techniques have been studied and procedures for implementation of importance sampling are suggested....
Block, Louis Stuart
1992-01-01
The behaviour under iteration of unimodal maps of an interval, such as the logistic map, has recently attracted considerable attention. It is not so widely known that a substantial theory has by now been built up for arbitrary continuous maps of an interval. The purpose of the book is to give a clear account of this subject, with complete proofs of many strong, general properties. In a number of cases these have previously been difficult of access. The analogous theory for maps of a circle is also surveyed. Although most of the results were unknown thirty years ago, the book will be intelligible to anyone who has mastered a first course in real analysis. Thus the book will be of use not only to students and researchers, but will also provide mathematicians generally with an understanding of how simple systems can exhibit chaotic behaviour.
Conformal constraints for anomalous dimensions of leading-twist operators
Energy Technology Data Exchange (ETDEWEB)
Manashov, A.N. [Institut fuer Theoretische Physik Universitaet Hamburg, Hamburg (Germany); University of Regensburg, Institut fuer Theoretische Physik, Regensburg (Germany); Saint-Petersburg State University, Department of Theoretical Physics, Saint-Petersburg (Russian Federation); Strohmaier, M. [University of Regensburg, Institut fuer Theoretische Physik, Regensburg (Germany)
2015-08-15
Leading-twist operators have a remarkable property that their divergence vanishes in a free theory. Recently it was suggested that this property can be used for an alternative technique to calculate anomalous dimensions of leading-twist operators and allows one to gain one order in perturbation theory so that, i.e., two-loop anomalous dimensions can be calculated from one-loop Feynman diagrams, etc. In this work we study the feasibility of this program by a toy-model example of the φ{sup 3} theory in six dimensions. Our conclusion is that this approach is valid, although it does not seem to present considerable technical simplifications as compared to the standard technique. It does provide one, however, with a very nontrivial check of the calculation as the structure of the contributions is very different. (orig.)
Spontaneous fission. A many-body approach
Energy Technology Data Exchange (ETDEWEB)
Iwamoto, Akira; Bonasera, A. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
1997-03-01
We propose new model to calculate the fission phenomena in tunnel region. By the Vlasov equation and the imaginary time method, we could calculate actinides nuclear fission. This method makes possible to describe unified the motion of fission inside and outside of potential wall. The potential energy and mass parameters can be calculated by no means of the special model. The freedom of internal motion are calculated automatically both collective and a particle motion. Accordingly, particle released during fission process can be calculated. The kinetic energy of fragment after fission was very agreeable with the calculation results. (S.Y.)
The Ethical Dimension of Innovation
DEFF Research Database (Denmark)
Nogueira, Leticia Antunes; Nogueira, Tadeu Fernando
2014-01-01
The view of innovation as a positive concept has been deeply rooted in business and academic cultures ever since Schumpeter coined the concept of creative destruction. Even though there is a large body of literature on innovation studies, limited attention has been given to its ethical dimension....... In this chapter, the ethical implications of innovations are illustrated with a case study of “destructive creation” in the food industry, and upon which an argumentative analysis is conducted. The main message of this chapter is that innovations have inherent ethical dimensions and that quality innovations...... depend on systematic consideration of these dimensions in the innovation process....
Black Holes in Higher Dimensions
International Nuclear Information System (INIS)
In four space-time dimensions black holes of Einstein-Maxwell theory satisfy a number of theorems. In more than four space-time dimensions, however, some of the properties of black holes can change. In particular, uniqueness of black holes no longer holds. In five and more dimensions black rings arise. Thus in a certain region of the phase diagram there are three black objects with the same global charges present. Here we discuss properties of higher-dimensional vacuum and charged black holes, which possess a spherical horizon topology, and of vacuum and charged black rings, which have a ringlike horizon topology
Nagata-Assouad dimension via Lipschitz extensions
Brodskiy, N.; Dydak, J.; Higes, J.; A. Mitra
2006-01-01
In the first part of the paper we show how to relate several dimension theories (asymptotic dimension with Higson property, asymptotic dimension of Gromov, and capacity dimension of Buyalo \\cite{Buyalo1}) to Nagata-Assouad dimension. This is done by applying two functors on the Lipschitz category of metric spaces: microscopic and macroscopic. In the second part we identify (among spaces of finite Nagata-Assouad dimension) spaces of Nagata-Assouad dimension at most $n$ as those for which the $...
Au coated Ni nanowires with tuneable dimensions for biomedical applications
Pondman, K.M.; Maijenburg, A.W.; Celikkol, F.B.; Pathan, A A; Kishore, U.D.; Haken, ten, Bennie; Elshof, ten, J.E.
2013-01-01
Due to their shape anisotropy, high aspect ratio magnetic nanoparticles offer many advantages in biomedical applications. For biocompatibility, it is essential to have full control over the dimensions and surface chemistry of the particles. The aim of this study was to synthesize biocompatible nanowires with tuneable dimensions. This was achieved by electrodeposition of Ni in polycarbonate membranes. To ensure biocompatibility, a continuous gold coating was deposited onto the Ni wires by a ne...
Grammatical evolution to design fractal curves with a given dimension
Ortega, Alfonso; Abu Dalhoum, Abdel Latif; Alfonseca, Manuel
2003-01-01
Lindenmayer grammars have frequently been applied to represent fractal curves. In this work, the ideas behind grammar evolution are used to automatically generate and evolve Lindenmayer grammars which represent fractal curves with a fractal dimension that approximates a predefined required value. For many dimensions, this is a nontrivial task to be performed manually. The procedure we propose closely parallels biological evolution because it acts through three different levels: a genotype (a ...
The limits of chemosensation vary across dimensions
Bicknell, Brendan A.; Dayan, Peter; Goodhill, Geoffrey J.
2015-06-01
Many biological processes rely on the ability of cells to measure local ligand concentration. However, such measurements are constrained by noise arising from diffusion and the stochastic nature of receptor-ligand interactions. It is thus critical to understand how accurately, in principle, concentration measurements can be made. Previous theoretical work has mostly investigated this in 3D under the simplifying assumption of an unbounded domain of diffusion, but many biological problems involve 2D concentration measurement in bounded domains, for which diffusion behaves quite differently. Here we present a theory of the precision of chemosensation that covers bounded domains of any dimensionality. We find that the quality of chemosensation in lower dimensions is controlled by domain size, suggesting a general principle applicable to many biological systems. Applying the theory to biological problems in 2D shows that diffusion-limited signalling is an efficient mechanism on time scales consistent with behaviour.
The social dimension of entrepreneurship
DEFF Research Database (Denmark)
Ulhøi, John Parm
2005-01-01
This paper proposes an integrative framework to conceptualize important social dimensions of entrepreneurship. The paper reviews and evaluates the current status of research dealing with entrepreneurship, social capital and trust. The proposed framework rests on the recognition that entrepreneurial...
Internal DLA in Higher Dimensions
Jerison, David; Sheffield, Scott
2010-01-01
Let A(t) denote the cluster produced by internal diffusion limited aggregation (internal DLA) with t particles in dimension d > 2. We show that A(t) is approximately spherical, up to an O(\\sqrt{\\log t}) error.
Dimension reduction for $-\\Delta_1$
Amendola, Maria Emilia; Gargiulo, Giuliano; Zappale, Elvira
2012-01-01
A 3D-2D dimension reduction for $-\\Delta_1$ is obtained. A power law approximation from $-\\Delta_p$ as $p \\to 1$ in terms of $\\Gamma$- convergence, duality and asymptotics for least gradient functions has also been provided.
Ethical dimension of scientific investigation
Antônio Joaquim Severino
2014-01-01
After emphasizing the growing concern about ethical issues related to scientific research involving human subjects by bodies responsible for the promotion of science in Brazil, this paper discusses the different perspectives under which relationships between ethics and production knowledge are established, highlighting the close connection of the ethical dimension to the political dimension, given the need for affirmation of otherness, for the presence of the other, so that one can discuss th...
Timbre Dimensions for Musical Control
Giese, Gregory Roy
This dissertation addresses the folowing question: Given the technologies to develop and implement any kind of sound generating and controlling device, what will the instrument designer, the composer, and the performer need to know in order to more fully utilize the dimensions of timbre in music and musical performance? This question is approached from the standpoint of music theory. Definitions of timbre and a few examples of related physical and perceptual research are reviewed. Included is a discussion of the essential elements of musical control and of intelligent organization of sound in music. This discussion raises more questions than can be answered simply. It is an attempt to unravel the nature of sound clues and sound qualities as they convey sound identities and musical gesture. A theoretical simplification of sound dimensions for musical use is proposed. Sounds which can be sustained indefinitely consist of steady-state acoustical dimensions. These dimensions rely upon the perceptual phenomenon of simultaneous fusion (synance). Sounds which can not be sustained indefinitely consist of transitions. Transitions may cause successive fusion (sonance). The discussion of steady-state and transition dimensions includes a review of a few informal experiments. This work reveals problems that will influence the musical use of timbre dimensions. It also leads to a theory for the organization and control of timbre dimensions in music. Among the timbre dimensions discussed are: spectral envelope, harmonic content, brightness, phase, inharmonicity, aperiodicity, and temporal transitions. Questions are raised regarding the perception of harmonic content. The effect of register on perception of tones consisting of from two to nine partials is explored and discussed. The size of interval between partials determines a unique quality. This is most apparent with tones consisting of only two or three partials (dions or trions).
Dimension reduction based on weighted variance estimate
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
In this paper, we propose a new estimate for dimension reduction, called the weighted variance estimate (WVE), which includes Sliced Average Variance Estimate (SAVE) as a special case. Bootstrap method is used to select the best estimate from the WVE and to estimate the structure dimension. And this selected best estimate usually performs better than the existing methods such as Sliced Inverse Regression (SIR), SAVE, etc. Many methods such as SIR, SAVE, etc. usually put the same weight on each observation to estimate central subspace (CS). By introducing a weight function, WVE puts different weights on different observations according to distance of observations from CS. The weight function makes WVE have very good performance in general and complicated situations, for example, the distribution of regressor deviating severely from elliptical distribution which is the base of many methods, such as SIR, etc. And compared with many existing methods, WVE is insensitive to the distribution of the regressor. The consistency of the WVE is established. Simulations to compare the performances of WVE with other existing methods confirm the advantage of WVE.
Collider phenomenology for models of extra dimensions
International Nuclear Information System (INIS)
In this talk, we summarize the collider phenomenology and recent experimental results for various models of extra dimensions, including the large extra dimensions (ADD model), warped extra dimensions (Randall-Sundrum model), TeV-1-sized extra dimensions with gauge bosons in the bulk, universal extra dimensions, and an 5D SU(5) SUSY GUT model in AdS space. (author)
Collider Phenomenology for models of extra dimensions
Cheung, Kingman
2003-01-01
In this talk, we summarize the collider phenomenology and recent experimental results for various models of extra dimensions, including the large extra dimensions (ADD model), warped extra dimensions (Randall-Sundrum model), TeV$^{-1}$-sized extra dimensions with gauge bosons in the bulk, universal extra dimensions, and an 5D SU(5) SUSY GUT model in AdS space.
Introducing many-body physics using atomic spectroscopy
Krebs, Dietrich; Santra, Robin
2013-01-01
Atoms constitute relatively simple many-body systems, making them suitable objects for developing an understanding of basic aspects of many-body physics. Photoabsorption spectroscopy is a prominent method to study the electronic structure of atoms and the inherent many-body interactions. In this article the impact of many-body effects on well-known spectroscopic features such as Rydberg series, Fano resonances, Cooper minima, and giant resonances is studied, and related many-body phenomena in other fields are outlined. To calculate photoabsorption cross sections the time-dependent configuration interaction singles (TDCIS) model is employed. The conceptual clearness of TDCIS in combination with the compactness of atomic systems allows for a pedagogical introduction to many-body phenomena.
Geometry, relativity and the fourth dimension
Rucker, Rudolf
1977-01-01
This is a highly readable, popular exposition of the fourth dimension and the structure of the universe. A remarkable pictorial discussion of the curved space-time we call home, it achieves even greater impact through the use of 141 excellent illustrations. This is the first sustained visual account of many important topics in relativity theory that up till now have only been treated separately.Finding a perfect analogy in the situation of the geometrical characters in Flatland, Professor Rucker continues the adventures of the two-dimensional world visited by a three-dimensional being to expl
Neutrino Mass Models in Extra Dimensions
Ng, J N
2003-01-01
Neutrinos play a crucial role in many areas of physics from very short distances to astrophysics and cosmology. It is a long held believe that they are good probes of physics at the GUT scale. Recent developments have made it clear that they can also be of fundamental importance for the physics of extra dimensions if these exist. Here we pedagogically review the construction of neutrino mass models in extra dimensions within the brane world scenarios. These models are usually nontrivial generalizations of their four dimensional counterparts. We describe the theoretical tools that have been forged and the new perpectives gained in this rapidly developing area. In particular we discuss the issues involve in building models without the use of right-handed singlets. It is very difficult to directly test the origin of neutrino masses in different models be it in four or more dimensions. We point out that different models give very different indirect signatures in the TeV region and in precision measurements.
Noncommutative inspired black holes in extra dimensions
International Nuclear Information System (INIS)
In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS took this smearing to be essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from ∼ 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the Terascale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We also demonstrate that the essential features of this approach are not particularly sensitive to the Gaussian nature of the smearing employed by NSS
Noncommutative Inspired Black Holes in Extra Dimensions
Energy Technology Data Exchange (ETDEWEB)
Rizzo, Thomas G.
2006-06-07
In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci (NSS) presented an interesting model for a noncommutative inspired, Schwarzschild-like black hole solution in 4-dimensions. The essential effect of having noncommutative co-ordinates in this approach is to smear out matter distributions on a scale associated with the turn-on of noncommutativity which was taken to be near the 4-d Planck mass. In particular, NSS assumed that this smearing was essentially Gaussian. This energy scale is sufficiently large that in 4-d such effects may remain invisible indefinitely. Extra dimensional models which attempt to address the gauge hierarchy problem, however, allow for the possibility that the effective fundamental scale may not be far from {approx} 1 TeV, an energy regime that will soon be probed by experiments at both the LHC and ILC. In this paper we generalize the NSS model to the case where flat, toroidally compactified extra dimensions are accessible at the TeV-scale and examine the resulting modifications in black hole properties due to the existence of noncommutativity. We show that while many of the noncommutativity-induced black hole features found in 4-d by NSS persist, in some cases there can be significant modifications due the presence of extra dimensions. We also demonstrate that the essential features of this approach are not particularly sensitive to the Gaussian nature of the smearing assumed by NSS.
Study of dose calculation on breast brachytherapy using prism TPS
Fendriani, Yoza; Haryanto, Freddy
2015-09-01
PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm3. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm3. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.
Study of dose calculation on breast brachytherapy using prism TPS
International Nuclear Information System (INIS)
PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm3. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm3. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy
Classification of surface EMG signal with fractal dimension
Institute of Scientific and Technical Information of China (English)
HU Xiao; WANG Zhi-zhong; REN Xiao-mei
2005-01-01
Surface EMG (electromyography) signal is a complex nonlinear signal with low signal to noise ratio (SNR). This paper is aimed at identifying different patterns of surface EMG signals according to fractal dimension. Two patterns of surface EMG signals are respectively acquired from the right forearm flexor of 30 healthy volunteers during right forearm supination (FS)or forearm pronation (FP). After the high frequency noise is filtered from surface EMG signal by a low-pass filter, fractal dimension is calculated from the filtered surface EMG signal. The results showed that the fractal dimensions of filtered FS surface EMG signals and those of filtered FP surface EMG signals distribute in two different regions, so the fractal dimensions can represent different patterns of surface EMG signals.
QCD in One Dimension at Nonzero Chemical Potential
Ravagli, L
2007-01-01
Using an integration formula recently derived by Conrey, Farmer and Zirnbauer, we calculate the expectation value of the phase factor of the fermion determinant for the staggered lattice QCD action in one dimension. We show that the chemical potential can be absorbed into the quark masses; the theory is in the same chiral symmetry class as QCD in three dimensions at zero chemical potential. In the limit of a large number of colors and fixed number of lattice points, chiral symmetry is broken spontaneously, and our results are in agreement with expressions based on a chiral Lagrangian. In this limit, the eigenvalues of the Dirac operator are correlated according to random matrix theory for QCD in three dimensions. The discontinuity of the chiral condensate is due to an alternative to the Banks-Casher formula recently discovered for QCD in four dimensions at nonzero chemical potential. The effect of temperature on the average phase factor is discussed in a schematic random matrix model.
On Gorenstein projective, injective and flat dimensions
DEFF Research Database (Denmark)
Christensen, Lars Winther; Frankild, Anders Juel; Holm, Henrik Granau
2006-01-01
Gorenstein homological dimensions are refinements of the classical homological dimensions, and finiteness singles out modules with amenable properties reflecting those of modules over Gorenstein rings. As opposed to their classical counterparts, these dimensions do not immediately come with pract...
Institute of Scientific and Technical Information of China (English)
无
2011-01-01
Compared with ellipse cavity, the spoke cavity has many advantages, especially for the low and medium beam energy. It will be used in the superconductor accelerator popular in the future. Based on the spoke cavity, we design and calculate an accelerator
International Nuclear Information System (INIS)
In this paper we study the spin-spin correlation function decay properties of the Blume-Emery-Griffiths (BEG) model with Hamiltonian located on the interface between the disordered and the anti-quadrupolar phases. On this interface, the BEG model has infinitely many ground state configurations. We show that, for any dimension d, there exists a parameter value, yd, below which the spin-spin correlation function with zero boundary condition decays exponentially fast at all non-zero temperatures. This result suggests that reentrant behaviour predicted by mean-field and numerical calculations may be absent for those values of parameters
Many Smokers Have COPD Symptoms, without Diagnosis
... gov/news/fullstory_158913.html Many Smokers Have COPD Symptoms, Without Diagnosis It's not clear how many ... smokers have symptoms of chronic obstructive pulmonary disease (COPD) even before they've been diagnosed with the ...
Blindness Biggest Fear for Many Americans
... page: https://medlineplus.gov/news/fullstory_160254.html Blindness Biggest Fear for Many Americans Losing vision would ... 4, 2016 THURSDAY, Aug. 4, 2016 (HealthDay News) -- Blindness is what many Americans fear most, a new ...
International Nuclear Information System (INIS)
Reviewed is the effect of heat flux of different system parameters on critical density in order to give an initial view on the value of several parameters. A thorough analysis of different equations is carried out to calculate burnout is steam-water flows in uniformly heated tubes, annular, and rectangular channels and rod bundles. Effect of heat flux density distribution and flux twisting on burnout and storage determination according to burnout are commended
LEGO Dimensions meets Doctor Who: Transbranding and New Dimensions of Transmedia Storytelling?
Directory of Open Access Journals (Sweden)
Matt Hills
2016-01-01
Full Text Available This article explores how the ‘toys-to-life’ videogame LEGO Dimensions (WarnerBros. Interactive Entertainment/Traveller’s Tales/The LEGO Group, 2015 mashes upmany different franchise storyworlds and brands. Specifically, I focus on how DoctorWho (BBC, 1963—, the British TV science fiction series, is licensed and transmediallyengaged with in Dimensions. I consider how the transbranding of LEGO Dimensionsappears to co-opt children’s “transgressive play” (Nørgård and Toft-Nielsen, 2014by combining intellectual properties, but actually continues to operate according tologics of shared corporate ownership where many of the combined storyworlds areultimately owned by Time Warner (placing Dimensions in competition with Disney’sown ‘toys-to-life’ game. Considering what value might accrue to the brand of DoctorWho by participating in LEGO Dimensions, I identify this as a particular example of“What If?” transmedia (Mittell, 2015, arguing that LEGO Dimensions’ Doctor Whonevertheless fluctuates in terms of its brand (inauthenticity. The Starter Pack remainscloser to LEGO Games’/Traveller’s Tales’ established format, subordinating Who, whilstthe separate Level Pack engages more precisely with Doctor Who’s history, albeit stilldisplaying some notable divergences from the TV series (Booth, 2015. Although LEGODimensions challenges influential theories of transmedia storytelling (Jenkins, 2006;Aldred, 2014, its transbranding and child/adult targeting accord with established approachesto transmedia licensing (Santo 2015 and fan-consumer socialization (Kinder1991.
Nuclear transport - The regulatory dimension
International Nuclear Information System (INIS)
The benefits that the peaceful applications of nuclear energy have brought to society are due in no small part to industry's capacity to transport radioactive materials safely, efficiently and reliably. The nuclear transport industry has a vital role in realising a fundamental objective of the International Atomic Energy Agency (IAEA) as stated in its statute to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world. The context in which transports currently take place is complex, and rapidly changing. In many respects transport is being viewed as an integral market issue and not a subsidiary concern. The availability of carriers drives routing decisions and changes in material flows necessitate new approaches to packaging and transport scenarios. Pressures on the transport sector are not without serious consequences; they can cause delays and in some cases cancellation of planned movements. Complex routings and the necessary use of chartered carriers can push up costs and work against cost efficiency. Since the events of 11 September 2001 the security of nuclear transports has contributed an added dimension to how transports take place. Transports of radioactive material have an outstanding safety record, indeed the transport of such materials could be regarded as a model for the transport of other classes of dangerous goods. This safety record is achieved by two inter-related factors. It is due primarily to well founded regulations developed by such key intergovernmental organisations as the IAEA, with the essential contributions of the member states who participate in the implementation of regulations and the review process. It is due also to the professionalism of those in the industry. There is a necessary synergy between the two - between the regulators whose task it is to make and to enforce the rules for safe, efficient and reliable transport and those whose job it is to transport within the rules. It
The Creative Dimension of Visuality
DEFF Research Database (Denmark)
Michelsen, Anders Ib
2013-01-01
analysis relying on language/linguistics as a model for explaining culture? More specifically, how can the – creative – novelty of visual culture be addressed by a notion of discourse? This essay will argue that the debate on visual culture is lacking with regard to discerning the creative dimension of its...... own appearance. It will indicate an alternative conceptual framework based on Johann P. Arnason’s draft of tripartite culturalization which focuses on a shift from essences to dimensions of culture. This will be further developed by relating Maurice Merleau-Ponty’s idea of ‘chiasm’ of ‘the visible...... and the invisible’ to the notion of collective creativity and ‘the imaginary institution of society’ of Cornelius Castoriadis. In the theoretical relationship between Merleau-Ponty and Castoriadis it is possible to indicate a notion of visuality as a creative dimension....
Reduced-Dimension Multiuser Detection
Xie, Yao; Goldsmith, Andrea
2011-01-01
We explore several reduced-dimension multiuser detection (RD-MUD) structures that significantly decrease the number of required correlation branches at the receiver front-end, while still achieving performance similar to that of the conventional matched-filter (MF) bank. RD-MUD exploits the fact that the number of active users is typically small relative to the total number of users in the system and relies on ideas of analog compressed sensing to reduce the number of correlators. We first develop a general framework for both linear and nonlinear RD-MUD detectors. We then present theoretical performance analysis for two specific detectors: the linear reduced-dimension decorrelating (RDD) detector, which combines subspace projection and thresholding to determine active users and sign detection for data recovery, and the nonlinear reduced-dimension decision-feedback (RDDF) detector, which combines decision-feedback orthogonal matching pursuit for active user detection and sign detection for data recovery. The t...
Twist operators in higher dimensions
Hung, Ling-Yan; Smolkin, Michael
2014-01-01
We study twist operators in higher dimensional CFT's. In particular, we express their conformal dimension in terms of the energy density for the CFT in a particular thermal ensemble. We construct an expansion of the conformal dimension in power series around n=1, with n being replica parameter. We show that the coefficients in this expansion are determined by higher point correlations of the energy-momentum tensor. In particular, the first and second terms, i.e. the first and second derivatives of the scaling dimension, have a simple universal form. We test these results using holography and free field theory computations, finding agreement in both cases. We also consider the `operator product expansion' of spherical twist operators and finally, we examine the behaviour of correlators of twist operators with other operators in the limit n ->1.
Personality dimensions of opiate addicts.
Vukov, M; Baba-Milkic, N; Lecic, D; Mijalkovic, S; Marinkovic, J
1995-02-01
A survey of 80 opiate addicts included in a detoxification program was conducted at the Institute on Addictions in Belgrade. In addition to a dependence diagnosis and mental disorders based on DSM-III-R, we applied a Tridimensional Personality Questionnaire (TPQ) that measures the 3 major personality dimensions: novelty-seeking (NS), harm avoidance (HA) and reward dependence (RD). When compared with a control group (a sample of Yugoslav undergraduate students), the opiate addicts demonstrate significantly high NS dimension as well as significant divergences of HA and RD subscales. The surveyed opiate addicts demonstrate a high percentage of personality disorders specifically in cluster B. The personality dimensions of opiate addicts showed certain temperament traits, such as: impulsiveness, shyness with strangers, fear of uncertainty and dependence. NS, HA and RD determined by temperament specifics may be an etiological factor in forming of a personality disorder, an affective disorder as well as of a drug choice.
Correlated Electrons in Reduced Dimensions
Energy Technology Data Exchange (ETDEWEB)
Bonesteel, Nicholas E [Florida State Univ., Tallahassee, FL (United States)
2015-01-31
This report summarizes the work accomplished under the support of US DOE grant # DE-FG02-97ER45639, "Correlated Electrons in Reduced Dimensions." The underlying hypothesis of the research supported by this grant has been that studying the unique behavior of correlated electrons in reduced dimensions can lead to new ways of understanding how matter can order and how it can potentially be used. The systems under study have included i) fractional quantum Hall matter, which is realized when electrons are confined to two-dimensions and placed in a strong magnetic field at low temperature, ii) one-dimensional chains of spins and exotic quasiparticle excitations of topologically ordered matter, and iii) electrons confined in effectively ``zero-dimensional" semiconductor quantum dots.
Statistically interacting quantum gases in D dimensions
Potter, Geoffrey G.
Chapter 1. Exact and explicit results are derived for the thermodynamic properties (isochores, isotherms, isobars, response functions, speed of sound) of a quantum gas in dimensions D ≥ 1 and with fractional exclusion statistics 0 ≤ g ≤ 1 connecting bosons (g = 0) and fermions (g = 1). In D = 1 the results are equivalent to those of the Calogero-Sutherland model, a gas with long-range two-body interaction. Emphasis is given to the crossover between boson-like and fermion-like features, caused by aspects of the statistical interaction that mimic long-range attraction and short-range repulsion. A phase transition along the isobar occurs at a nonzero temperature in all dimensions. The T-dependence of the speed of sound is in simple relation to isochores and isobars. The effects of soft container walls are accounted for rigorously for the case of a pure power-law potential. Chapter 2. The exact thermodynamics (isochores, isotherms, isobars, response functions, speed of sound) is worked out for a statistically interacting quantum gas in D dimensions. The results in D = 1 are those of the thermodynamic Bethe ansatz for the Nonlinear Schrodinger model, a gas with repulsive two-body contact potential. In all dimensions the ideal boson and fermion gases are recovered in the weak-coupling and strong-coupling limits, respectively. For all nonzero couplings ideal fermion gas behavior emerges for D >> 1 and, in the limit D → infinity, a phase transition occurs at T > 0. Significant deviations from ideal quantum gas behavior are found for intermediate coupling and finite D . Chapter 3. Methodology previously developed in the framework of the coordinate Bethe ansatz applied to integrable quantum gas models is employed to calculate some ground-state properties and elementary excitations for quantum gas models in D = 1 dimensions with statistical interactions that are not equivalent to dynamical interactions. The focus in this comparative study is on modifications of the
Sonographic Measurement of Renal Dimensions in Adults and its Correlates
Directory of Open Access Journals (Sweden)
Iffat Yazdani
2012-09-01
Full Text Available Background: Unilateral or bilateral changes in kidney size are manifested by many renal diseases and to recognize these anatomical deviations, it is important to have standard sonographic measurements for appropriate comparison. Our primary aim was to determine a normal range of values for renal dimensions in our asymptomatic adult population and to correlate renal length with measures of renal function as a secondary objective. Methods: A cross-sectional population survey was conducted at two spaced-out densely populated areas in the city of Karachi, Pakistan. Ultrasound was preformed and blood samples collected from 225 healthy individuals with no known renal pathology and with normal calculated GFR. Results: Mean kidney lengths were 9.85cm (95% CI: 9.74-9.95 cm on right side and 10.0 cm (9.85-10.1 cm on left. The mean width was 4.61cm (95%CI: 4.53 – 4.68cm, cortical thickness 1.46 cm (CI 1.43-1.49cm with estimated average kidney volume 35.7 cm3 (CI: 34.1-36.5 cm3. Males had larger kidney sizes than females (p < 0.001; age however was only associated with a decrease in renal length after ages 70 and above.(p=0.001 Renal length best correlated with body weight (correlation coefficient 0.384 .eGFR, representative of renal function also positively correlated with renal length (Coefficient 0.415. A multivariate analysis showed male gender (OR 1.60, age (OR 0.89, weight (OR 1.02 and height (OR 7.77 to be significant independent predictors of renal length. Conclusion: We established the normal values for renal dimensions in our adult population. Our study signifies the potential of ultrasound as a useful tool for diagnostic and follow-up purposes of kidney–associated diseases. By extending this research and including data from other parts of the country; we can formulate a gender and age specific nomogram for kidney dimensions for adequate comparison in evaluation of kidney diseases.
Muon-proton colliders: Leptoquarks, contact interactions and extra dimensions
International Nuclear Information System (INIS)
We discuss the physics potential of the μp collider; especially, leptoquarks, leptogluons, R-parity violating squarks, contact interactions, and large extra dimensions. We calculate the sensitivity reach for these new physics at μp colliders of various energies and luminosities
Muon-proton Colliders: Leptoquarks, Contact Interactions and Extra Dimensions
Cheung, Kingman
2000-01-01
We discuss the physics potential of the $\\mu p$ collider; especially, leptoquarks, leptogluons, R-parity violating squarks, contact interactions, and large extra dimensions. We calculate the sensitivity reach for these new physics at $\\mu p$ colliders of various energies and luminosities.
Hertz potentials in higher dimensions
International Nuclear Information System (INIS)
We generalise the Hertz potentials to all spacetime dimensions D ≥4 and to all antisymmetric tensor fields. We show that the Whittaker-Debye-Bromwich reduction of the Hertz potential can be successfully exploited in all dimensions and for all antisymmetric tensor fields if the underlying spacetime is a warped product manifold. We illustrate the Hertzian approach by constructing the multipole expansions of all antisymmetric tensor fields on a D-dimensional Schwarzschild solution. A no-hair theorem for the D-dimensional black holes follows from these multipole expansions. (author)
The Territorial Dimensions of Education
Moore, Niamh; Ancien, Delphine
2013-01-01
The ‘Europe 2020 Strategy’ was issued in 2010 by the European Commission. This document constitutes a growth scheme for the decade 2010-2020 that aims to help the European Union to emerge from the current crisis through the so-called smart, sustainable and inclusive dimensions of growth. In this context, the basic aim of the SIESTA (“Spatial Indicators for a ‘Europe 2020 Strategy’ Territorial Analysis”) Project has been to illustrate the territorial dimension of the ‘Europe 2020 Strategy’. In...
McCarty, George
1982-01-01
How THIS BOOK DIFFERS This book is about the calculus. What distinguishes it, however, from other books is that it uses the pocket calculator to illustrate the theory. A computation that requires hours of labor when done by hand with tables is quite inappropriate as an example or exercise in a beginning calculus course. But that same computation can become a delicate illustration of the theory when the student does it in seconds on his calculator. t Furthermore, the student's own personal involvement and easy accomplishment give hi~ reassurance and en couragement. The machine is like a microscope, and its magnification is a hundred millionfold. We shall be interested in limits, and no stage of numerical approximation proves anything about the limit. However, the derivative of fex) = 67.SgX, for instance, acquires real meaning when a student first appreciates its values as numbers, as limits of 10 100 1000 t A quick example is 1.1 , 1.01 , 1.001 , •••• Another example is t = 0.1, 0.01, in the functio...
International Nuclear Information System (INIS)
Risk and reliability analysis is increasingly being used in evaluations of plant safety and plant reliability. The analysis can be performed either during the design process or during the operation time, with the purpose to improve the safety or the reliability. Due to plant complexity and safety and availability requirements, sophisticated tools, which are flexible and efficient, are needed. Such tools have been developed in the last 20 years and they have to be continuously refined to meet the growing requirements. Two different areas of application were analysed. In structural reliability probabilistic approaches have been introduced in some cases for the calculation of the reliability of structures or components. A new computer program has been developed based upon numerical integration in several variables. In systems reliability Monte Carlo simulation programs are used especially in analysis of very complex systems. In order to increase the applicability of the programs variance reduction techniques can be applied to speed up the calculation process. Variance reduction techniques have been studied and procedures for implementation of importance sampling are suggested. (author)
Dimensionally continued Oppenheimer-Snyder gravitational collapse ; 2, solutions in odd dimensions
Ilha, A; Lemos, J P S; Ilha, Anderson; Kleber, Antares; Lemos, Jose' P. S.
1999-01-01
The Lovelock gravity extends the theory of general relativity to higher dimensions in such a way that the field equations remain of second order. The theory has many constant coefficients with no a priori meaning. Nevertheless it is possible to reduce them to two, the cosmological constant and Newton's constant. In this process one separates theories in even dimensions from theories in odd dimensions. In a previous work gravitational collapse in even dimensions was analysed. In this work attention is given to odd dimensions. It is found that black holes also emerge as the final state of gravitational collapse of a regular dust fluid.
40 Years of Calculus in 4 + epsilon Dimensions
Bietenholz, Wolfgang
2012-01-01
Modern physics describes elementary particles by a formalism known as Quantum Field Theory. However, straight calculations with this formalism lead to numerous divergences, hence one needs a suitable regularization scheme. 40 years ago a surprising scheme was established for this purpose: Dimensional Regularization. One computes in "4 + epsilon space-time dimensions", and takes the limit to our 4 dimensional space-time at the end. This method caused a revolution in particle physics, which led to the Standard Model. Many people refer to its results, and even apply it, without being aware that its history actually started in Latin America, more precisely in La Plata, Argentina. ----- La f\\'isica moderna describe a las part\\'iculas elementales por medio del formalismo conocido como Teor\\'ia Cu\\'antica de Campos. Sin embargo, los c\\'alculos directos realizados con este formalismo llevan a una gran cantidad de divergencias, por lo que es necesario un m\\'etodo para regularizarlos. Hace 40 a\\~nos se estableci\\'o un ...
Massive Gravity in Three Dimensions
Bergshoeff, Eric A; Townsend, Paul K
2009-01-01
A particular higher-derivative extension of the Einstein-Hilbert action in three spacetime dimensions is shown to be equivalent at the linearized level to the (unitary) Pauli-Fierz action for a massive spin-2 field. We discuss the extension to massive ${\\cal N}$-extended supergravity, and we present a `cosmological' extension admitting a supersymmetric anti-de Sitter vacuum.
Quantum Gravity in Two Dimensions
DEFF Research Database (Denmark)
Ipsen, Asger Cronberg
The topic of this thesis is quantum gravity in 1 + 1 dimensions. We will focus on two formalisms, namely Causal Dynamical Triangulations (CDT) and Dy- namical Triangulations (DT). Both theories regularize the gravity path integral as a sum over triangulations. The difference lies in the class...
A small dimension intraoperative probe
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
This article introduces the usage of the intraoperative probe in surgical based on RGS and proposes one method to design the probe. Also, a charge-sensitive preamplifier used in semiconductor detector was constructed which can reduce the dimension of the probe. At last the probe is tested by some animal experiments. Results showed that the property of this system are reliable.
Massive Gravity in Three Dimensions
Bergshoeff, Eric A.; Hohm, Olaf; Townsend, Paul K.
2009-01-01
A particular higher-derivative extension of the Einstein-Hilbert action in three spacetime dimensions is shown to be equivalent at the linearized level to the (unitary) Pauli-Fierz action for a massive spin-2 field. A more general model, which also includes "topologically-massive" gravity as a speci
Competitive dimensions of human resources
Directory of Open Access Journals (Sweden)
Neykova Rumyana Mykolaivna
2015-02-01
Full Text Available This article deals with the essence of human resources competitive dimensions. Their competitive priorities are analyzed in dynamic business environment, with an emphasis on the quality of human resources, their adaptive skills, communication skills and mobility. The attention is paid to the role behavior of personnel and the policies for its management in the context of cutting down management costs.
The Dimensions of Residential Segregation.
Massey, Douglas S.; Denton, Nancy A.
1988-01-01
Evaluates 20 potential indicators of residential segregation using census data on Hispanics, Blacks, Asians, and non-Hispanic Whites in 60 U.S. metropolitan areas. Factor-analyzes the results to select a single best indicator for each of five dimensions of residential segregation. Contains 69 references and 22 statistical formulas. (SV)
The inner dimension of sustainability
Horlings, L.G.
2015-01-01
Transformation to sustainability has been defined as the fundamental alteration of the nature of a system, once the current conditions become untenable or undesirable. Transformation requires a shift in people's values, referred to as the inner dimension of sustainability, or change from the inside-
Spectral dimension of the universe
Ambjørn, J.; Jurkiewicz, J.; Loll, R.
2006-01-01
We measure the spectral dimension of universes emerging from nonperturbative quantum gravity, defined through state sums of causal triangulated geometries. While four-dimensional on large scales, the quantum universe appears two-di- mensional at short distances. We conclude that quantum gravity may
Selfdual Substitutions in Dimension One
Berthé, Valérie; Sirvent, Victor
2011-01-01
There are several notions of the 'dual' of a word/tile substitution. We show that the most common ones are equivalent for substitutions in dimension one, where we restrict ourselves to the case of two letters/tiles. Furthermore, we obtain necessary and sufficient arithmetic conditions for substitutions being selfdual in this case.
Representation dimension for Hopf actions
Institute of Scientific and Technical Information of China (English)
SUN JuXiang; LIU GongXiang
2012-01-01
Let H be a finite-dimensional Hopf algebra and assume that both H and H* are semisimple.The main result of this paper is to show that the representation dimension is an invariant under cleft extensions of H,that is,rep.dim(A) =rep.dim(A#σH).Some of the applications of this equality are also given.
Manual tracking in three dimensions.
Mrotek, L.A.; Gielen, C.C.A.M.; Flanders, M.
2006-01-01
Little is known about the manual tracking of targets that move in three dimensions. In the present study, human subjects followed, with the tip of a hand-held pen, a virtual target moving four times (period 5 s) around a novel, unseen path. Two basic types of target paths were used: a peanut-shaped
Multiple dimensions of cardiopulmonary dyspnea
Institute of Scientific and Technical Information of China (English)
HAN Jiang-na; XIONG Chang-ming; YAO Wei; FANG Qiu-hong; ZHU Yuan-jue; CHENG Xian-sheng; Karel P Van de Woestijne
2011-01-01
Background The current theory of dyspnea perception presumes a multidimensional conception of dyspnea.However,its validity in patients with cardiopulmonary dyspnea has not been investigated.Methods A respiratory symptom checklist incorporating spontaneously reported descriptors of sensory experiences of breathing discomfort,affective aspects,and behavioral items was administered to 396 patients with asthma,chronic obstructive pulmonary disease (COPD),diffuse parenchymal lung disease,pulmonary vascular disease,chronic heart failure,and medically unexplained dyspnea.Symptom factors measuring different qualitative components of dyspnea were derived by a principal component analysis.The separation of patient groups was achieved by a variance analysis on symptom factors.Results Seven factors appeared to measure three dimensions of dyspnea:sensory (difficulty breathing and phase of respiration,depth and frequency of breathing,urge to breathe,wheeze),affective (chest tightness,anxiety),and behavioral (refraining from physical activity) dimensions.Difficulty breathing and phase of respiration occurred more often in COPD,followed by asthma (R2=0.12).Urge to breathe was unique for patients with medically unexplained dyspnea (R2=0.12).Wheeze occurred most frequently in asthma,followed by COPD and heart failure (R2=0.17).Chest tightness was specifically linked to medically unexplained dyspnea and asthma (R2=0.04).Anxiety characterized medically unexplained dyspnea (R2=0.08).Refraining from physical activity appeared more often in heart failure,pulmonary vascular disease,and COPD (R2=0.15).Conclusions Three dimensions with seven qualitative components of dyspnea appeared in cardiopulmonary disease and the components under each dimension allowed separation of different patient groups.These findings may serve as a validation on the multiple dimensions of cardiopulmonary dyspnea.
Treatment Effects with Many Covariates and Heteroskedasticity
DEFF Research Database (Denmark)
Cattaneo, Matias D.; Jansson, Michael; Newey, Whitney K.
propose a new heteroskedasticity consistent standard error formula that is fully automatic and robust to both (conditional) heteroskedasticity of unknown form and the inclusion of possibly many covariates. We apply our findings to three settings: (i) parametric linear models with many covariates, (ii...
A remark on asymptotic dimension and digital dimension of finite metric spaces
Čatyrko, Vitalij Al´bertovič; Zarichnyi, Michael
2015-01-01
Asymptotic dimension was introduced by M. L. Gromov as an asymptotic analogue of the covering dimension. In the current note, the authors introduce the concept of digital dimension (essentially asymptotic dimension at a particular scale) and investigate the relationship between the asymptotic dimension of a proper metric space and the digital dimension of its finite subspaces. In particular, they show that the asymptotic dimension of a proper metric space is at most ▫$n$▫ exactly when there i...
About Fermion Hierarchies from Warped Extra Dimensions
Lawrance, Robert
2014-01-01
We consider fermions propagating in the bulk of the geometry found by deforming AdS, in 5 dimensions, via the back reaction of a scalar field upon the metric. This space is AdS for r asymptotically large (in the UV) but goes through a transition at a point, into another AdS space with different curvature in the IR. Masses are generated for these fermions via electroweak symmetry breaking, by coupling them to a VEV on the IR boundary. We calculate the mass spectrum in four dimensions, comparing approximate results and results found by solving the full system of bulk equations and boundary conditions. We consider the effect on the mass of the light modes of various parameters, including the curvature of the space in the IR. This information is then used to reproduce the mass hierarchy between the top and bottom. By assuming universality of the gauge coupling, we find bounds on the allowed bulk masses of the right--handed fermion fields. We look for solutions that satisfy these bounds in a number of different sc...
International Nuclear Information System (INIS)
I will outline three-particle calculations, and results, in one dimension with delta-function interactions, in two dimensions for square wells and in three dimensions with delta shells. The presentation will be that of my own work, obtained together with colleagues. The initial approach is that of expansions of the wave function in terms of Hyperspherical adiabatic functions, usually deduced from hyperspherical harmonics. Refs. 15 (author)
QED shift calculations in relativistic many-electron atoms and ions
Tupitsyn, I I; Safronova, M S; Shabaev, V M; Dzuba, V A
2016-01-01
We incorporated quantum electrodynamics (QED) corrections into the broadly-applicable high-precision relativistic method that combines configuration interaction (CI) and linearized coupled-cluster approaches. With the addition of the QED, this CI+all-order method allows one to accurately predict properties of heavy ions of particular interest to the design of precision atomic clocks and tests of fundamental physics. To evaluate the accuracy of the QED contributions and test various QED models, we incorporated four different one-electron QED potentials. We demonstrated that all of them give consistent and reliable results. For the strongly bound electrons (i.e. inner electrons of heavy atoms, or valence electrons in highly-charged ions), the nonlocal potentials are more accurate, than the local one. Results are presented for cases of particular experimental interest.
International Nuclear Information System (INIS)
We present a numerical integration scheme for evaluating the convolution of a Green's function with a screened Coulomb potential on the real axis in the GW approximation of the self energy. Our scheme takes the zero broadening limit in Green's function first, replaces the numerator of the integrand with a piecewise polynomial approximation, and performs principal value integration on subintervals analytically. We give the error bound of our numerical integration scheme and show by numerical examples that it is more reliable and accurate than the standard quadrature rules such as the composite trapezoidal rule. We also discuss the benefit of using different self energy expressions to perform the numerical convolution at different frequencies
The RPA calculation os bandhead energies in many-boson systems
International Nuclear Information System (INIS)
The RPA is used to correct the Hartree self-consistent single-boson energies. The spurious states that appear as a consequence of broken symmetries are set at zero energy and can therefore be eliminated. The method is exemplified with an SU3 hamiltonian with only s and d bosons. (orig.)
Au coated Ni nanowires with tuneable dimensions for biomedical applications
Pondman, K.M.; Maijenburg, A.W.; Celikkol, F.B.; Pathan, A.A.; Kishore, U.D.; Haken, ten B.; Elshof, ten J.E.
2013-01-01
Due to their shape anisotropy, high aspect ratio magnetic nanoparticles offer many advantages in biomedical applications. For biocompatibility, it is essential to have full control over the dimensions and surface chemistry of the particles. The aim of this study was to synthesize biocompatible nanow
New Dimensions to Psychosocial Development in Traditionally Aged College Students
Blimling, Gregory S.
2013-01-01
Why do so many traditionally aged college students engage in inappropriate behaviors, even when they are smart enough to know better? To answer this question, Gregory S. Blimling looks at some of the latest neuroscience research and, in doing so, introduces a new dimension to understanding psychosocial development in college…
Apaches in Three Dimensions: Anthropology, History and Literature.
Oliva, Leo E.
As many disciplines as possible should be used in the teaching of Indian Studies. In particular, creative literature adds another dimension to the understanding of Indian culture and the history of Indian-white relations when it is used in conjunction with historical and anthropological material. The serious student should read historical novels…
A Toy Model of Electrodynamics in (1 + 1) Dimensions
Boozer, A. D.
2007-01-01
A model is presented that describes a scalar field interacting with a point particle in (1+1) dimensions. The model exhibits many of the same phenomena that appear in classical electrodynamics, such as radiation and radiation damping, yet has a much simpler mathematical structure. By studying these phenomena in a highly simplified model, the…
Publication Ethics: Many Facets, Collaboration Required
Viroj Wiwanitkit
2013-01-01
Sir, the recent publication on “Publication Ethics” is very interesting (1). The article by Fazly Bazzaz and Sadeghi demonstrated many interesting cases of misconducts. Indeed, the misconducts can be seen in many ways. As mentioned in the present publication, both author and editor can perform publication misconducts. Nevertheless, the problem has many more facets. Sometimes, the misconducts are generated by the third parties. For example, the publisher...
Negentropy in Many-Body Quantum Systems
Directory of Open Access Journals (Sweden)
Piero Quarati
2016-02-01
Full Text Available Negentropy (negative entropy is the negative contribution to the total entropy of correlated many-body environments. Negentropy can play a role in transferring its related stored mobilizable energy to colliding nuclei that participate in spontaneous or induced nuclear fusions in solid or liquid metals or in stellar plasmas. This energy transfer mechanism can explain the observed increase of nuclear fusion rates relative to the standard Salpeter screening. The importance of negentropy in these specific many-body quantum systems and its relation to many-body correlation entropy are discussed.
Localized gravity on de Sitter brane in five dimensions
Ito, M
2003-01-01
We consider a single brane embedded in five dimensions with vanishing and positive bulk cosmological constant. In this setup, the existence of $dS_{4}$ brane is allowed. Exploring the gravitational fluctuations on the brane, we show that the usual four-dimensional gravity can be reproduced by a normalizable zero mode and the continuous massive modes are separated by a mass gap from zero mode. Finally we calculate the relation among the cosmological constant in the brane, and the fundamental scale of five dimensions and Planck scale.
Applying EFT to Higgs pair production in universal extra dimensions
Edelhäuser, Lisa; Knochel, Alexander; Steeger, Thomas
2015-11-01
We investigate single Higgs and Higgs pair production at the LHC in models of Universal Extra Dimensions. After calculating the relevant cross sections, we use the UED model as a testing ground for the Effective Field Theory approach to physics beyond the Standard Model. We show how the UED contributions to Higgs production can be matched to a dimension-6 operator. We then discuss the range of validity of this approach, in particular for Higgs pair production, and determine the sensitivity to the number of KK modes in the loop.
Resistance of Feynman diagrams and the percolation backbone dimension.
Janssen, H K; Stenull, O; Oerding, K
1999-06-01
We present an alternative view of Feynman diagrams for the field theory of random resistor networks, in which the diagrams are interpreted as being resistor networks themselves. This simplifies the field theory considerably as we demonstrate by calculating the fractal dimension D(B) of the percolation backbone to three loop order. Using renormalization group methods we obtain D(B)=2+epsilon/21-172epsilon(2)/9261+2epsilon(3)[-74 639+22 680zeta(3)]/4 084 101, where epsilon=6-d with d being the spatial dimension and zeta(3)=1.202 057... .
Statistical theory of the many-body nuclear system
De Pace, A
2002-01-01
A recently proposed statistical theory of the mean fields associated with the ground and excited collective states of a generic many-body system is extended by increasing the dimensions of the P-space. In applying the new framework to nuclear matter, in addition to the mean field energies we obtain their fluctuations as well, together with the ones of the wavefunctions, in first order of the expansion in the complexity of the Q-space states. The physics described by the latter is assumed to be random. To extract numerical predictions out of our scheme we develop a schematic version of the approach, which, while much simplified, yields results of significance on the size of the error affecting the mean fields, on the magnitude of the residual effective interaction, on the ground state spectroscopic factor and on the mixing occurring between the vectors spanning the P-space.
Many COPD Patients Have Trouble Finding Care
... https://medlineplus.gov/news/fullstory_158830.html Many COPD Patients Have Trouble Finding Care They can face ... first comprehensive look at chronic obstructive pulmonary disease (COPD) care in the United States. COPD is the ...
Sun Protection Comes in Many Forms
... nlm.nih.gov/medlineplus/news/fullstory_159096.html Sun Protection Comes in Many Forms Thorough and frequent ... is that people are much more savvy about sun exposure," Pameijer said in a center news release. ...
The many faces of basal cell carcinoma
Jackson, Robert
1982-01-01
Basal cell carcinoma is the most easily cured carcinoma, but because of the many forms it can take, and because it grows so slowly, it can be misdiagnosed or neglected. The author discusses its more common forms and etiologic considerations.
Flavor Symmetries in Extra Dimensions
Aranda, A; Aranda, Alfredo
2002-01-01
We present a model of flavor based on a discrete local symmetry that reproduces all fermion masses and mixing angles both in the quark and lepton sectors. The particle content of the model is that of the standard model plus an additional flavon field. All the fields propagate in a fifth universal extra dimension and the flavor scale is associated with the cutoff of the 5D theory which is $\\sim 10$ TeV. The Yukawa matrices as well as the Majorana mass matrix for the neutrinos are generated by higher dimension operators involving the flavon field. When the flavon field acquires a vacuum expectation value it breaks the flavor symmetry and thus generates the Yukawa couplings. The model is consistent with the nearly bimaximal solution to the solar and atmospheric neutrino deficits.
INTERDEPENDENCE BETWEEN RELATIONSHIP QUALITY DIMENSIONS
Directory of Open Access Journals (Sweden)
Mario Pepur
2011-02-01
Full Text Available Tourism-dependent economy, unfavourable structure of accommodation and hotel capacity, seasonality of business and liquidity problems indicate importance of the relationships between hotels and banks in Croatia. Since the capital investments in new and modern capacities are necessity, the quality of their relationship would determine the future of Croatian economy as a whole in the long run. Regarding the capital investments, it is crucially important that cooperation between the employees in both business entities is based on the satisfaction, trust and commitment. In this way, every potential uncertainty as a consequence of the entity’s actions could be minimized. In this paper, 356 tourist objects are hierarchically clustered according to the relationship quality dimensions for the purpose of testing the characteristics according to which the clusters significantly differentiate. Consequently, the interdependence between the observed relationship quality dimensions is examined.
Neutrinos Confronting Large Extra Dimensions
Maalampi, J; Vilja, I
2001-01-01
We study neutrino physics in a model with one large extra dimension. We assume the existence of two four-dimensional branes in the five-dimensional space-time, one for the ordinary particles and the other one for mirror particles, and we investigate neutrino masses and mixings in this scheme. Comparison of experimental neutrino data with the predictions of the model leads to various restrictions on the parameters of the model. For instance, the size of the extra dimension, R, turns out to be bounded from below. Cosmological considerations seem to favor a large R. The usual mixing schemes proposed as solutions to the solar and atmospheric neutrino anomalies are compatible with our model.
Double Semions in Arbitrary Dimension
Freedman, Michael H.; Hastings, Matthew B.
2016-10-01
We present a generalization of the double semion topological quantum field theory to higher dimensions, as a theory of {d-1} dimensional surfaces in a d dimensional ambient space. We construct a local Hamiltonian that is a sum of commuting projectors and analyze the excitations and the ground state degeneracy. Defining a consistent set of local rules requires the sign structure of the ground state wavefunction to depend not just on the number of disconnected surfaces, but also upon their higher Betti numbers through the semicharacteristic. For odd d the theory is related to the toric code by a local unitary transformation, but for even d the dimension of the space of zero energy ground states is in general different from the toric code and for even {d > 2} it is also in general different from that of the twisted {Z_2} Dijkgraaf-Witten model.
Distributed Memory Programming on Many-Cores
DEFF Research Database (Denmark)
Berthold, Jost; Dieterle, Mischa; Lobachev, Oleg;
2009-01-01
is tailored to networks of workstations. Recent work has shown that this implementation shows surprisingly competitive performance on many-core machines, compared to dedicated shared-memory implementations of parallel Haskell. In the paper we describe a case study with different Eden divide......-and-conquer skeletons. We analyse their performance comparing example applications implemented using these Eden skeletons against parallel Haskell implementations using shared memory on many-core machines...
The Many Victims of Substance Abuse
Mauro, Tara
2007-01-01
Substance abuse is a complicated disorder and has far reaching consequences. The victims of substance abuse extend beyond the unfortunate ones suffering from this disorder and often include family and friends. Treatment options for substance abuse are many; however, positive outcomes are not always guaranteed. Many factors play into the potential for successful treatment. Some of these include the adherence and motivation of the substance abusing patients as well as patients' surrounding envi...
Læsningens sproglige dimension
DEFF Research Database (Denmark)
Mulvad, Ruth; Kabel, Kristine
2007-01-01
Flere af projekterne i Nationalt Videncenter for Læsning arbejder for at styrke læsning gennem et kombineret fokus på teksters sproglige dimension og på den pædagogiske kontekst, som teksterne indgår i. To af dem har som mål at designe et kompetenceløft for seminarieundervisere og at udvikle...
Optical Tomography in Two Dimensions
Stefanov, Plamen
2003-01-01
We consider in two dimensions, the inverse boundary problem of reconstructing the absorption and scattering coefficient of an inhomogeneous medium by probing it with diffuse light. The problem is modeled as an inverse boundary problem for the stationary linear Boltzmann equation. The information is encoded in the albedo operator. We show that we can recover the absorption and the scattering kernel from this information provided that the latter is small in an appropriate t...
Dimensions of problem based learning
DEFF Research Database (Denmark)
Nielsen, Jørgen Lerche; Andreasen, Lars Birch
2013-01-01
The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning...... and Learning (MIL). We discuss changes in the roles of the teachers as supervisors within this learning environment, and we explore the involvement of students as active participants and co-designers of how course and project activities unfold....
The social dimensions of entrepreneurship
DEFF Research Database (Denmark)
Ulhøi, John Parm
2005-01-01
This paper proposes an integrative framework to conceptualize important social dimensions of entrepreneurship. The paper reviews and evaluates the current status of research dealing with entrepreneurship, social capital and trust. The proposed framework rests on the recognition that entrepreneurial...... activities are results of social interactions and mechanisms. In consequence, entrepreneurship cannot merely be understood in terms of "personality characteristics" or in sterile economic terms. In closing, the paper addresses implications for practitioners and for research. Udgivelsesdato: AUG...
The dimensions of purchasing competence
Rodrigues, Cristina S.; Fernandes, Edite Manuela da G. P.; Martins, F. Vitorino
2006-01-01
As firms recognize the purchasing function as an important resource for obtaining high quality levels, fast deliveries and cost savings, it reveals opportunities for the purchasing management to become a key contributor. The new product development is one example where acquisition capabilities may confirm to be particularly critical. This paper presents a construct of purchasing competence using three dimensions identified from literature: purchasing interaction, purchasing importance, and...
Administrative Dimensions of Tax Reform
Bird, Richard M.
2003-01-01
The best tax policy in the world is worth little if it cannot be implemented effectively. Tax policy design in developing countries must therefore take the administrative dimension of taxation carefully into account. What can be done may to a considerable extent determine what is done in any country. This paper discusses the relationship between tax policy and tax administration. When can policy lead administration? When must policy initiatives wait on administrative reform? How exactly can b...
Gravity Waves in Three Dimensions
Gurses, Metin; Tekin, Bayram
2015-01-01
We find the explicit forms of the anti-de Sitter plane, anti-de Sitter spherical, and pp waves that solve both the linearized and exact field equations of the most general higher derivative gravity theory in three dimensions. As a sub-class, we work out the six derivative theory and the critical version of it where the masses of the two spin-2 excitations vanish and the spin-0 excitations decouple.
Massive Gravity in Three Dimensions
Bergshoeff, Eric A.; Hohm, Olaf; Townsend, Paul K
2009-01-01
A particular higher-derivative extension of the Einstein-Hilbert action in three spacetime dimensions is shown to be equivalent at the linearized level to the (unitary) Pauli-Fierz action for a massive spin-2 field. A more general model, which also includes `topologically-massive' gravity as a special case, propagates the two spin 2 helicity states with different masses. We discuss the extension to massive ${\\cal N}$-extended supergravity, and we present a `cosmological' extension that admits...
Signal detection in high dimension
Hallin, Marc; Moreira, Marcelo J.; Onatski, Alexei
2012-01-01
This paper deals with the local asymptotic structure, in the sense of Le Cam’s asymptotic theory of statistical experiments, of the signal detection problem in high dimension. More precisely, we consider the problem of testing the null hypothesis of sphericity of a high-dimensional covariance matrix against an alternative of (unspecified) multiple symmetry-breaking directions (multispiked alternatives). Simple analytical expressions for the asymptotic power envelope and the ...
Brief communication: age and fractal dimensions of human sagittal and coronal sutures
DEFF Research Database (Denmark)
Lynnerup, Niels; Jacobsen, Jens Christian Brings
2003-01-01
The fractal dimensions of human sagittal and coronal sutures were calculated on 31 complete skulls from the Terry Collection. The aim was to investigate whether the fractal dimension, relying on the whole sutural length, might yield a better description of age-related changes in sutural morpholog...
The Hausdorff and dynamical dimensions of self-affine sponges: a dimension gap result
Das, Tushar; Simmons, David
2016-01-01
We construct a self-affine sponge in $\\mathbb R^3$ whose dynamical dimension, i.e. the supremum of the Hausdorff dimensions of its invariant measures, is strictly less than its Hausdorff dimension. This resolves a long-standing open problem in the dimension theory of dynamical systems, namely whether every expanding repeller has an ergodic invariant measure of full Hausdorff dimension.
Wormholes leading to extra dimensions
Bronnikov, K A
2016-01-01
In 6D general relativity with a scalar field as a source of gravity, a new type of static wormhole solutions is presented: such wormholes connect our universe with a small 2D extra subspace with a universe where this extra subspace is large, and the whole space-time is effectively 6-dimensional. We consider manifolds with the structure M0 x M1 x M2 , where M0 is 2D Lorentzian space-time while each of M1 an M2 can be a 2-sphere or a 2-torus. After selecting possible asymptotic behaviors of the metric functions compatible with the field equations, we give two explicit examples of wormhole solutions with spherical symmetry in our space-time and toroidal extra dimensions. In one example, with a massless scalar field (it is a special case of a well-known more general solution), the extra dimensions have a large constant size at the "far end"; the other example contains a nonzero potential $V(\\phi)$ which provides a 6D anti-de Sitter asymptotic, where all spatial dimensions are infinite.
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...
How many subjects do I need to power my study?
Sergio R. Muñoz Navarro
2014-01-01
The article presents a tool that helps answer the question “How many subjects do I need to power my study? We show how to determine sample size in observational epidemiological studies and provide examples of application using the statistical package Epidat, which is a shareware program developed under the auspices of the Pan American Health Organization, the Galician Board of Health and the University CES of Colombia. Examples of calculation of sample size for prevalence studies (cross-secti...
Longitudinal and Transverse Spin Responses in Relativistic Many Body Theory
Yoshida, K; Toki, H.
1998-01-01
Spin longitudinal and transverse response function are studied by means of the relativistic many-body theory. The spin response functions in the relativistic theory are largely reduced from those in the non-relativistic theory. The local density approximation with the eikonal approximation is applied to the the nuclear absorption in the $(\\vec{p},\\vec{n})$ reactions on C and Ca. We compare the calculated results with the recent experimental data.
Many-body chaos at weak coupling
Stanford, Douglas
2016-10-01
The strength of chaos in large N quantum systems can be quantified using λ L , the rate of growth of certain out-of-time-order four point functions. We calculate λ L to leading order in a weakly coupled matrix Φ4 theory by numerically diagonalizing a ladder kernel. The computation reduces to an essentially classical problem.
Instrument Transformer Dimensioning for Substations
Mustajärvi, Ronny
2016-01-01
This thesis was made for ABB Oy, Power Grids unit. Some customers demand instrument transformer calculations, which state that the current transformers can accurately reproduce the occurring fault currents without saturation. The aim of the thesis was to get familiar with relevant instrument transformer theory and to create a calculation template. With the data of the current transformer, secondary cables and the used protection function it is possible to calculate that the current transf...
Mental number space in three dimensions.
Winter, Bodo; Matlock, Teenie; Shaki, Samuel; Fischer, Martin H
2015-10-01
A large number of experimental findings from neuroscience and experimental psychology demonstrated interactions between spatial cognition and numerical cognition. In particular, many researchers posited a horizontal mental number line, where small numbers are thought of as being to the left of larger numbers. This review synthesizes work on the mental association between space and number, indicating the existence of multiple spatial mappings: recent research has found associations between number and vertical space, as well as associations between number and near/far space. We discuss number space in three dimensions with an eye on potential origins of the different number mappings, and how these number mappings fit in with our current knowledge of brain organization and brain-culture interactions. We derive novel predictions and show how this research fits into a general view of cognition as embodied, grounded and situated.
Framing the Human Dimension in Cybersecurity
Directory of Open Access Journals (Sweden)
J. Nixon
2013-05-01
Full Text Available The advent of technologies that can seamlessly operate in different environments with differing levels of security present new challenges to the cybersecurity specialist seeking to ensure the safety of data, process or output of a complex system. This paper reviews the human dimension of cybersecurity. The Human Factors Integration (HFI framework is employed as a structure with which to consider the many ways in which the human can differentially affect the security of a system both positively and negatively. We conclude that when the human factors element is analysed when specifying and designing secure and safe systems, it is far more likely that the human can assist and increase the overall level of security. As in other high technology sectors such as aviation or petrochemical, if not considered, the human can often ‘bulldoze’ through the most carefully considered and designed security or safety barriers
Extra dimensions, orthopositronium decay, and stellar cooling
Friedland, Alexander
2007-01-01
In a class of extra dimensional models with a warped metric and a single brane the photon can be localized on the brane by gravity only. An intriguing feature of these models is the possibility of the photon escaping into the extra dimensions. The search for this effect has motivated the present round of precision orthopositronium decay experiments. We point out that in this framework a photon in plasma should be metastable. We consider the astrophysical consequences of this observation, in particular, what it implies for the plasmon decay rate in globular cluster stars and for the core-collapse supernova cooling rate. The resulting bounds on the model parameter exceed the possible reach of orthopositronium experiments by many orders of magnitude.
Dimensions of attractors in pinched skew products
Gröger, M
2011-01-01
We study dimensions of strange non-chaotic attractors and their associated physical measures in so-called pinched skew products, introduced by Grebogi and his coworkers in 1984. Our main results are that the Hausdorff dimension, the pointwise dimension and the information dimension are all equal to one, although the box-counting dimension is known to be two. The assertion concerning the pointwise dimension is deduced from the stronger result that the physical measure is rectifiable. Our findings confirm a conjecture by Ding, Grebogi and Ott from 1989.
Constraints on extra dimensions from precision molecular spectroscopy
Salumbides, E J; Gato-Rivera, B; Ubachs, W
2015-01-01
Accurate investigations of quantum level energies in molecular systems are shown to provide a test ground to constrain the size of compactified extra dimensions. This is made possible by the recent progress in precision metrology with ultrastable lasers on energy levels in neutral molecular hydrogen (H$_2$, HD and D$_2$) and the molecular hydrogen ions (H$_2^+$, HD$^+$ and D$_2^+$). Comparisons between experiment and quantum electrodynamics calculations for these molecular systems can be interpreted in terms of probing large extra dimensions, under which conditions gravity will become much stronger. Molecules are a probe of space-time geometry at typical distances where chemical bonds are effective, i.e. at length scales of an \\AA. Constraints on compactification radii for extra dimensions are derived within the Arkani-Hamed-Dimopoulos-Dvali framework, while constraints for curvature or brane separation are derived within the Randall-Sundrum framework. Based on the molecular spectroscopy of D$_2$ molecules an...
Static hybrid potential in D dimensions at short distances
International Nuclear Information System (INIS)
We compute the energy of a static hybrid, i.e., of a hybrid quarkonium with static quark and antiquark, at short distances in D=4,3, dimensions. The soft contribution to this energy is the static potential of a color-octet quark-antiquark pair at short distances, which is known at two loops for arbitrary D. We have checked this expression employing thermal field theory methods. Using the effective field theory potential nonrelativistic QCD we calculate the ultrasoft contributions to the hybrid (and singlet) static energy at the two-loop level. We then present new results for the static hybrid energy/potential and the hybrid decay width in three and four dimensions. Finally we comment on the meaning of the perturbative results in two space-time dimensions, where the hybrid does not exist.
FRACTIONAL INTEGRALS OF THE WEIERSTRASS FUNCTIONS:THE EXACT BOX DIMENSION
Institute of Scientific and Technical Information of China (English)
Zhou Songping; Yao Kui; Su Weiyi
2004-01-01
The present paper investigates the fractal structure of fractional integrals of Weierstrass functions.The exact box dimension for such functions many important cases is established. We need to point out that, although the result itself achieved in the present paper is interesting, the new technique and method should be emphasized. These novel ideas might be useful to establish the box dimension or Hausdorff dimension (especially for the lower bounds) for more general groups of functions.
Dimensions of source credibility in the case of user-generated advertisements
Lauzon-Duguay, Annie
2012-01-01
User-generated advertising changed the world of advertising and changed the strategies used by marketers. Many researchers explored the dimensions of source credibility in traditional media and online advertising. However, little previous research explored the dimensions of source credibility in the context of user-generated advertising. This exploratory study aims to investigate the different dimensions of source credibility in the case of user-generated advertising. More precisely, this stu...
Introduction to many-body physics
Coleman, Piers
2015-01-01
A modern, graduate-level introduction to many-body physics in condensed matter, this textbook explains the tools and concepts needed for a research-level understanding of the correlated behavior of quantum fluids. Starting with an operator-based introduction to the quantum field theory of many-body physics, this textbook presents the Feynman diagram approach, Green's functions and finite-temperature many body physics before developing the path integral approach to interacting systems. Special chapters are devoted to the concepts of Fermi liquid theory, broken symmetry, conduction in disordered systems, superconductivity and the physics of local-moment metals. A strong emphasis on concepts and numerous exercises make this an invaluable course book for graduate students in condensed matter physics. It will also interest students in nuclear, atomic and particle physics.
Anomalous mass dimension of multi-flavor QCD
Doff, A
2016-01-01
Models of strongly interacting theories with a large mass anomalous dimension ($\\gamma_m$) provide an interesting possibility for the dynamical origin of the electroweak symmetry breaking. A laboratory for these models is QCD with many flavors, which may present a non-trivial fixed point associated to a conformal region. Studies based on conformal field theories and on Schwinger-Dyson equations have suggested the existence of bounds on the mass anomalous dimension at the fixed points of these models. In this note we discuss $\\gamma_m$ values of multi-flavor QCD exhibiting a non-trivial fixed point and affected by relevant four-fermion interactions.
Intelligent Graph Layout Using Many Users' Input.
Yuan, Xiaoru; Che, Limei; Hu, Yifan; Zhang, Xin
2012-12-01
In this paper, we propose a new strategy for graph drawing utilizing layouts of many sub-graphs supplied by a large group of people in a crowd sourcing manner. We developed an algorithm based on Laplacian constrained distance embedding to merge subgraphs submitted by different users, while attempting to maintain the topological information of the individual input layouts. To facilitate collection of layouts from many people, a light-weight interactive system has been designed to enable convenient dynamic viewing, modification and traversing between layouts. Compared with other existing graph layout algorithms, our approach can achieve more aesthetic and meaningful layouts with high user preference.
Many-body interactions and nuclear structure
Hjorth-Jensen, M; Hagen, G; Kvaal, S
2010-01-01
This article presents several challenges to nuclear many-body theory and our understanding of the stability of nuclear matte r. In order to achieve this, we present five different cases, starting with an idealized toy model. These cases expose problems that need to be understood in order to match recent advances in nuclear theory with current experimental programs in low-energy nuclear physics. In particular, we focus on our current understanding, or lack thereof, of many-body forces, and how they evolve as functions of the number of particles . We provide examples of discrepancies between theory and experiment and outline some selected perspectives for future research directions.
Quantum scaling in many-body systems
Continentino, Mucio A
2001-01-01
This book on quantum phase transitions has been written by one of the pioneers in the application of scaling ideas to many-body systems - a new and exciting subject that has relevance to many areas of condensed matter and theoretical physics. One of the few books on the subject, it emphasizes strongly correlated electronic systems. Although dealing with complex problems in statistical mechanics, it does not lose sight of the experiments and the actual physical systems which motivate the theoretical work. The book starts by presenting the scaling theory of quantum critical phenomena. Critical e
Quantum theory of many-particle systems
Fetter, Alexander L
2003-01-01
""Singlemindedly devoted to its job of educating potential many-particle theorists…deserves to become the standard text in the field."" - Physics Today""The most comprehensive textbook yet published in its field and every postgraduate student or teacher in this field should own or have access to a copy."" - EndeavorA self-contained, unified treatment of nonrelativistic many-particle systems, this text offers a solid introduction to procedures in a manner that enables students to adopt techniques for their own use. Its discussions of formalism and applications move easily between general theo
The many ways of making anionic clays
Indian Academy of Sciences (India)
Michael Rajamathi; Grace S Thomas; P Vishnu Kamath
2001-10-01
Together with hydrotalcite-like layered double hydroxides, bivalent and trivalent metal hydroxides and their hydroxy salts are actually anionic clays consisting of positively charged hydroxide layers with anions intercalated in the interlayer region. The anionic clays exhibit anion sorption, anion diffusion and exchange properties together with surface basicity making them materials of importance for many modern applications. In this article, we discuss many different ways of making anionic clays and compare and contrast the rich diversity of this class of materials with the better-known cationic clays.
Many diseases, one model of care?
Albreht, T.; Dyakova, M.; Schellevis, F.G.; Broucke, S. van den
2016-01-01
Patients with multiple chronic conditions (multimorbidity) have complex and extensive health and social care needs that are not well served by current silo-based models of care. A lack of integration between care providers often leads to fragmented, incomplete, and ineffective care, leaving many pat
Too Many Kids Are Getting Killed.
Molnar, Alex
1992-01-01
For too many children, our society is a fearful wasteland that mocks adult pieties and nurtures nihilism. The threat of violence cannot be dispelled with metal detectors, weapons checks, and secured hallways. Educators must adopt classroom practices that promote and strengthen peaceful relations among students and become more effective advocates…
Responses of fractal dimensions of Picea koraiensis seedlings to different light environments
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
The changes of fractal dimension of Picea koraiensis seedlings under different light intensities in natural secondary forests was studied. The results showed that with the change of light environment, crown characters of Picea koraiensis seedlings exhibited a greater plastic in lateral number, lateral increment, lateral dry weight, and specific leaf area. The range of calculated fractal dimensions of seedling crowns was confined between 2.5728 and 2.1036, but maximum of fractal dimension achieved in term moderate shading and in extreme low light conditions fractal dimension was least.
On aether terms in a space-time with a compact extra dimension
Mariz, T; Petrov, A Yu
2016-01-01
In this paper, for the CPT-even and CPT-odd extensions of the QED, we explicitly obtain the aether-like corrections for the electromagnetic field in the case when the space-time involves an extra compact spatial dimension besides of usual four dimensions. Our methodology is based on an explicit summation over the Kaluza-Klein tower of fields which is no more difficult than the finite-temperature calculations. The quantum corrections turn out to be large as the extra dimension is small. We demonstrate that in the CPT-even case, the extra dimension manifests itself through a new scalar particle.
Self-forces on static bodies in arbitrary dimensions
Harte, Abraham I.; Flanagan, Éanna É.; Taylor, Peter
2016-06-01
We derive exact expressions for the scalar and electromagnetic self-forces and self-torques acting on arbitrary static extended bodies in arbitrary static spacetimes with any number of dimensions. Nonperturbatively, our results are identical in all dimensions. Meaningful point particle limits are quite different in different dimensions, however. These limits are defined and evaluated, resulting in simple "regularization algorithms" which can be used in concrete calculations. In these limits, self-interaction is shown to be progressively less important in higher numbers of dimensions; it generically competes in magnitude with increasingly high-order extended-body effects. Conversely, we show that self-interaction effects can be relatively large in 1 +1 and 2 +1 dimensions. Our motivations for this work are twofold: First, no previous derivation of the self-force has been provided in arbitrary dimensions, and heuristic arguments presented by different authors have resulted in conflicting conclusions. Second, the static self-force problem in arbitrary dimensions provides a valuable test bed with which to continue the development of general, nonperturbative methods in the theory of motion. Several new insights are obtained in this direction, including a significantly improved understanding of the renormalization process. We also show that there is considerable freedom to use different "effective fields" in the laws of motion—a freedom which can be exploited to optimally simplify specific problems. Different choices give rise to different inertias, gravitational forces, and electromagnetic or scalar self-forces, but there is a sense in which none of these quantities are individually accessible to experiment. Certain combinations are observable, however, and these remain invariant under all possible field redefinitions.
Strings, branes and extra dimensions
International Nuclear Information System (INIS)
In an attempt to gain a better understanding of our world, various philosophers, mathematicians and physicists have, over the last few centuries, proposed that we might live in a world with more than four space-time dimensions. In the 17th century, for example, Emmanuel Kant tried to figure out what is special about a three spatial-dimensional world. He concluded that there could be other universes hidden from our senses - an idea that Democritus among others had also entertained. (U.K.)
Low Dimension Semiconducting Composite Nanomaterials
Institute of Scientific and Technical Information of China (English)
WANG Mang; CHEN Hong-zheng; SUN Jing-zhi
2004-01-01
Recently, low dimension nanostructures have gained considerable attention due to their technological potential as unique types of nanoscale building blocks for future optoelectronic devices and systems. Semiconducting composite nanomaterials, which can combine the advantages of two or more components, have been the focus in the area of nanomaterials synthesis and device application.In this paper, we report our work on the preparation of composite nanomaterials based on CNTs.CNTs were coated by organic or inorganic species via novel and facile methods (Fig. 1 and Fig.2).These functional CNTs based composites show eminent prospects and opportunities for new applications in a wide variation of areas.
Correlation dimension of complex networks
Lacasa, Lucas
2012-01-01
We propose a new measure to characterize the dimension of complex networks based on the ergodic theory of dynamical systems. This measure is derived from the correlation sum of a trajectory generated by a random walker navigating the network, and extends the classical Grassberger-Procaccia algorithm to the context of complex networks. The method is validated with reliable results for both synthetic networks and real-world networks such as the world air-transportation network or urban networks, and provides a computationally fast way for estimating the dimensionality of networks which only relies on the local information provided by the walkers.
Quantum cosmology near two dimensions
Bautista, Teresa; Dabholkar, Atish
2016-08-01
We consider a Weyl-invariant formulation of gravity with a cosmological constant in d -dimensional spacetime and show that near two dimensions the classical action reduces to the timelike Liouville action. We show that the renormalized cosmological term leads to a nonlocal quantum momentum tensor which satisfies the Ward identities in a nontrivial way. The resulting evolution equations for an isotropic, homogeneous universe lead to slowly decaying vacuum energy and power-law expansion. We outline the implications for the cosmological constant problem, inflation, and dark energy.
The fourth dimension simply explained
Manning, Henry P
2005-01-01
To remove the contents of an egg without puncturing its shell or to drink the liquor in a bottle without removing the cork is clearly unthinkable - or is it? Understanding the world of Einstein and curved space requires a logical conception of the fourth dimension.This readable, informative volume provides an excellent introduction to that world, with 22 essays that employ a minimum of mathematics. Originally written for a contest sponsored by Scientific American, these essays are so well reasoned and lucidly written that they were judged to merit publication in book form. Their easily unders
Cultural Dimensions Of Legal Discourse
Directory of Open Access Journals (Sweden)
Sierocka Halina
2014-09-01
Full Text Available Despite the intention for precision and accuracy, legal discourse is oftentimes complex, archaic and ambiguous - which gives rise to contentious interpretation. Moreover, little or no attention is paid to the cultural dimension of legal discourse, which plays a critical role in the translation and interpretation of legal texts, as well as in the application of law. This paper endeavours to illustrate the impact the culture, or, more precisely, legal culture has on the way legal texts are construed or translated and to present problems which arise in the interpretation, translation and application of law as a result of cultural diversities
Fractal dimension of bioconvection patterns
Noever, David A.
1990-01-01
Shallow cultures of the motile algal strain, Euglena gracilis, were concentrated to 2 x 10 to the 6th organisms per ml and placed in constant temperature water baths at 24 and 38 C. Bioconvective patterns formed an open two-dimensional structure with random branches, similar to clusters encountered in the diffusion-limited aggregation (DLA) model. When averaged over several example cultures, the pattern was found to have no natural length scale, self-similar branching, and a fractal dimension (d about 1.7). These agree well with the two-dimensional DLA.
NONHOMOGENEOUS HOPF EQUATIONS IN HIGHER DIMENSIONS
Institute of Scientific and Technical Information of China (English)
JIU QUANSEN
1999-01-01
The existence and uniqueness of the localclassical solution of nonhomogenuous Hopf equationsin higher dimensions are proved in this paper. Thissolution is obtained by vanishing the viscosity termof Burger's equations in higher dimensions.
Personality dimensions and disorders in pathological gambling
DEFF Research Database (Denmark)
Odlaug, Brian Lawrence; Schreiber, Liana R N; Grant, Jon E
2013-01-01
This review presents the most current research in personality dimensions and disorders with respect to pathological gambling.......This review presents the most current research in personality dimensions and disorders with respect to pathological gambling....
Lee, Byung Dae; Park, Je Min; Lee, Young Min; Moon, Eunsoo; Jeong, Hee Jeong; Chung, Young In; Yi, Young Mi
2016-01-01
Objective Categorical syndromes such as schizophrenia may represent complexes of many continuous psychological structural phenotypes along several dimensions of personality development/degeneration. The present study investigated the heritability and familiality of personality dimensions in Korean families with schizophrenic linkage disequilibrium (LD). Methods We recruited 179 probands (with schizophrenia) as well as, whenever possible, their parents and siblings. We used the Temperament and...
HOFSTEDE’S CULTURAL DIMENSIONS AND MANAGEMENT IN CORPORATIONS
Directory of Open Access Journals (Sweden)
Alexandrina Cristina VASILE
2016-06-01
Full Text Available In many cases the success or failure in management is caused by the way leaders understand the cultural environment the companies develop. The leadership approach and rules applied increase or decrease performance in economies and companies. The paper describes the relation between management failure or success and the management adjustment to the cultural dimensions. People build organizations and rule them according to their values, but in the corporation field specific values might be successfully applied or implying the whole company failure. The analysis is made based on Hofstede research and having in mind his dimensions on a dynamic hypothetical case where there are taken into account cultural dimensions for Romania, Germany, Kazakhstan and United States of America.
BOOK REVIEW: Quantum Physics in One Dimension
Logan, David
2004-05-01
To a casual ostrich the world of quantum physics in one dimension may sound a little one-dimensional, suitable perhaps for those with an unhealthy obsession for the esoteric. Nothing of course could be further from the truth. The field is remarkably rich and broad, and for more than fifty years has thrown up innumerable challenges. Theorists, realising that the role of interactions in 1D is special and that well known paradigms of higher dimensions (Fermi liquid theory for example) no longer apply, took up the challenge of developing new concepts and techniques to understand the undoubted pecularities of one-dimensional systems. And experimentalists have succeeded in turning pipe dreams into reality, producing an impressive and ever increasing array of experimental realizations of 1D systems, from the molecular to the mesoscopic---spin and ladder compounds, organic superconductors, carbon nanotubes, quantum wires, Josephson junction arrays and so on. Many books on the theory of one-dimensional systems are however written by experts for experts, and tend as such to leave the non-specialist a touch bewildered. This is understandable on both fronts, for the underlying theoretical techniques are unquestionably sophisticated and not usually part of standard courses in many-body theory. A brave author it is then who aims to produce a well rounded, if necessarily partial, overview of quantum physics in one dimension, accessible to a beginner yet taking them to the edge of current research, and providing en route a thorough grounding in the fundamental ideas, basic methods and essential phenomenology of the field. It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated. Aimed in particular at graduate students in theoretical condensed matter physics, and assumimg little theoretical background on the part of the reader (well just a little), Giamarchi writes in a refreshingly
The Many Faces of Graph Dynamics
Pignolet, Yvonne Anne; Schmid, Stefan; Tredan, Gilles
2016-01-01
The topological structure of complex networks has fascinated researchers for several decades, resulting in the discovery of many universal properties and reoccurring characteristics of different kinds of networks. However, much less is known today about the network dynamics: indeed, complex networks in reality are not static, but rather dynamically evolve over time. Our paper is motivated by the empirical observation that network evolution patterns seem far from random, but exhibit structure. Moreover, the specific patterns appear to depend on the network type, contradicting the existence of a "one fits it all" model. However, we still lack observables to quantify these intuitions, as well as metrics to compare graph evolutions. Such observables and metrics are needed for extrapolating or predicting evolutions, as well as for interpolating graph evolutions. To explore the many faces of graph dynamics and to quantify temporal changes, this paper suggests to build upon the concept of centrality, a measure of no...
Many-Task Computing and Blue Waters
Katz, Daniel S; Zhang, Zhao; Wilde, Michael; Wozniak, Justin M
2012-01-01
This report discusses many-task computing (MTC) generically and in the context of the proposed Blue Waters systems, which is planned to be the largest NSF-funded supercomputer when it begins production use in 2012. The aim of this report is to inform the BW project about MTC, including understanding aspects of MTC applications that can be used to characterize the domain and understanding the implications of these aspects to middleware and policies. Many MTC applications do not neatly fit the stereotypes of high-performance computing (HPC) or high-throughput computing (HTC) applications. Like HTC applications, by definition MTC applications are structured as graphs of discrete tasks, with explicit input and output dependencies forming the graph edges. However, MTC applications have significant features that distinguish them from typical HTC applications. In particular, different engineering constraints for hardware and software must be met in order to support these applications. HTC applications have tradition...
The Doomsday Argument, Consciousness and Many Worlds
Eastmond, J F G
2002-01-01
The doomsday argument is a probabilistic argument that claims to predict the total lifetime of the human race. By examining the case of an individual lifetime, I conclude that the argument is fundamentally related to consciousness. I derive a reformulation stating that an infinite conscious lifetime is not possible even in principle. By considering a hypothetical conscious computer, running a non-terminating program, I deduce that consciousness cannot be generated by a single set of deterministic laws. Instead, I hypothesize that consciousness is generated by a superposition of brain states that is simultaneously associated with many quasi-classical histories, each following a different set of deterministic laws. I generalize the doomsday argument and discover that it makes no prediction in this case. Thus I conclude that the very fact of our consciousness provides us with evidence for a many-worlds interpretation of reality in which our future is not predictable using anthropic reasoning.
DIMENSIONS FOR RANDOM SELF-CONFORMAL SETS
Institute of Scientific and Technical Information of China (English)
Liu Yanyan; Wu Jun
2003-01-01
A set is called regular if its Hausdorff dimension and upper box-counting dimension coincide.In this paper,we prove that the random self-conformal set is regular almost surely.Also we determine the dimensions for a class of random self-conformal sets.
Speaker Identification Based on Fractal Dimensions
Institute of Scientific and Technical Information of China (English)
侯丽敏; 王朔中
2003-01-01
This paper discusses application of fractal dimensions to speech processing. Generalized dimensions of arbitrary orders and associated fractal parameters are used in speaker identification. A characteristic vactor based on these parameters is formed, and a recognition criterion definded in order to identify individual speakers. Experimental results show the usefulness of fractal dimensions in characterizing speaker identity.
Ising formulations of many NP problems
Lucas, Andrew
2014-02-01
We provide Ising formulations for many NP-complete and NP-hard problems, including all of Karp's 21 NP-complete problems. This collects and extends mappings to the Ising model from partitioning, covering and satisfiability. In each case, the required number of spins is at most cubic in the size of the problem. This work may be useful in designing adiabatic quantum optimization algorithms.
Many-body effects in ionic systems
Wilson, Mark; Madden, Paul A.; Paul Madden
1994-01-01
The electron density of an ion is strongly influenced by its environment in a condensed phase. When the environment changes, for example due to thermal motion, non-trivial changes in the electron density, and hence the interionic interactions occur. These interactions give rise to many-body effects in the potential. In order to represent this phenomenon in molecular dynamics (MD) simulations a method has been developed in which the environmentally-induced changes in the ionic p...
Many worlds interpretation for double slit experiment
Yun, Zinkoo
2014-01-01
As is well known, the double slit experiment contains every key concepts of quantum mechanics such as phase effect, probability wave, quantum interference, quantum superposition. In this article, I will clarify the meaning of quantum superposition in terms of phase effect between states. After applying standard quantum theory, it leads to serious questions about the unitary process of an isolated system. It implies that non collapsing interpretations including many worlds may not be justified...
Tube morphogenesis: closure, but many openings remain
Nelson, W. James
2003-01-01
Epithelial and endothelial tubes form the basic structure of many organs and tissues in the fruit fly Drosophila melanogaster, the nematode Caenorhabditis elegans, zebrafish and mammals. Comparison of how tubes form during development defines several pathways that generate a single unbranched tube or dichotomously branching tubular networks. The formation of tubes can be induced directly by intrinsic signals within epithelial primordia or by inductive signaling between adjacent epithelia and ...
Many human accelerated regions are developmental enhancers
John A Capra; Erwin, Genevieve D.; McKinsey, Gabriel; Rubenstein, John L R; Pollard, Katherine S
2013-01-01
The genetic changes underlying the dramatic differences in form and function between humans and other primates are largely unknown, although it is clear that gene regulatory changes play an important role. To identify regulatory sequences with potentially human-specific functions, we and others used comparative genomics to find non-coding regions conserved across mammals that have acquired many sequence changes in humans since divergence from chimpanzees. These regions are good candidates for...
Topological dimension and dynamical systems
Coornaert, Michel
2015-01-01
Translated from the popular French edition, the goal of the book is to provide a self-contained introduction to mean topological dimension, an invariant of dynamical systems introduced in 1999 by Misha Gromov. The book examines how this invariant was successfully used by Elon Lindenstrauss and Benjamin Weiss to answer a long-standing open question about embeddings of minimal dynamical systems into shifts. A large number of revisions and additions have been made to the original text. Chapter 5 contains an entirely new section devoted to the Sorgenfrey line. Two chapters have also been added: Chapter 9 on amenable groups and Chapter 10 on mean topological dimension for continuous actions of countable amenable groups. These new chapters contain material that have never before appeared in textbook form. The chapter on amenable groups is based on Følner’s characterization of amenability and may be read independently from the rest of the book. Although the contents of this book lead directly to several active ar...
Fractal Dimensions of Macromolecular Structures
Todoroff, Nickolay; Kunze, Jens; Schreuder, Herman; Hessler, Gerhard; Baringhaus, Karl-Heinz; Schneider, Gisbert
2014-01-01
Quantifying the properties of macromolecules is a prerequisite for understanding their roles in biochemical processes. One of the less-explored geometric features of macromolecules is molecular surface irregularity, or ‘roughness’, which can be measured in terms of fractal dimension (D). In this study, we demonstrate that surface roughness correlates with ligand binding potential. We quantified the surface roughnesses of biological macromolecules in a large-scale survey that revealed D values between 2.0 and 2.4. The results of our study imply that surface patches involved in molecular interactions, such as ligand-binding pockets and protein-protein interfaces, exhibit greater local fluctuations in their fractal dimensions than ‘inert’ surface areas. We expect approximately 22 % of a protein’s surface outside of the crystallographically known ligand binding sites to be ligandable. These findings provide a fresh perspective on macromolecular structure and have considerable implications for drug design as well as chemical and systems biology. PMID:26213587
Non-equilibrium many body dynamics
International Nuclear Information System (INIS)
This Riken BNL Research Center Symposium on Non-Equilibrium Many Body Physics was held on September 23-25, 1997 as part of the official opening ceremony of the Center at Brookhaven National Lab. A major objective of theoretical work at the center is to elaborate on the full spectrum of strong interaction physics based on QCD, including the physics of confinement and chiral symmetry breaking, the parton structure of hadrons and nuclei, and the phenomenology of ultra-relativistic nuclear collisions related to the up-coming experiments at RHIC. The opportunities and challenges of nuclear and particle physics in this area naturally involve aspects of the many body problem common to many other fields. The aim of this symposium was to find common theoretical threads in the area of non-equilibrium physics and modern transport theories. The program consisted of invited talks on a variety topics from the fields of atomic, condensed matter, plasma, astrophysics, cosmology, and chemistry, in addition to nuclear and particle physics. Separate abstracts have been indexed into the database for contributions to this workshop
Fractal dimension of microbead assemblies used for protein detection
Hecht, Ariel; Commiskey, Patrick; Lazaridis, Filippos; Argyrakis, Panos
2014-01-01
We use fractal analysis to calculate the protein concentration in a rotating magnetic assembly of microbeads of size 1μm, which has optimized parameters of sedimentation, binding sites and magnetic volume. We utilize the original Forrest-Witten method, but due to the relatively small number of bead particles, which is of the order of 500, we use a large number of origins and also a large number of algorithm iterations. We find a value of the fractal dimension in the range 1.70–1.90, as a function of the thrombin concentration, which plays the role of binding the microbeads together. This is in good agreement with previous results from magnetorotation studies. The calculation of the fractal dimension using multiple points of reference can be used for any assembly with a relatively small number of particles. PMID:25195559
Directory of Open Access Journals (Sweden)
Jose Wicto Pereira Borges
2013-10-01
Full Text Available The objective of the study was to validate the content of the dimensions that constituted nonadherence to treatment of arterial systemic hypertension. It was a methodological study of content validation. Initially an integrative review was conducted that demonstrated four dimensions of nonadherence: person, disease/treatment, health service, and environment. Definitions of these dimensions were evaluated by 17 professionals, who were specialists in the area, including: nurses, pharmacists and physicians. The Content Validity Index was calculated for each dimension (IVCi and the set of the dimensions (IVCt, and the binomial test was conducted. The results permitted the validation of the dimensions with an IVCt of 0.88, demonstrating reasonable systematic comprehension of the phenomena of nonadherence.
A Technique for Calculating Quantum Corrections to Solitons
Barnes, Chris; Turok, Neil
1997-01-01
We present a numerical scheme for calculating the first quantum corrections to the properties of static solitons. The technique is applicable to solitons of arbitrary shape, and may be used in 3+1 dimensions for multiskyrmions or other complicated solitons. We report on a test computation in 1+1 dimensions, where we accurately reproduce the analytical result with minimal numerical effort.
Fractal dimension crossovers in turbulent passive scalar signals
Grossmann, Siegfried; Lohse, Detlef
1994-01-01
The fractal dimension δg(1) of turbulent passive scalar signals is calculated from the fluid dynamical equation. δg(1) depends on the scale. For small Prandtl (or Schmidt) number Pr < 10-2 one gets two ranges, δg(1) = 1 for small-scale r and δg(1) = 5/3 for large r, both as expected. But for large P
Benchmarking the Nelder-Mead Downhill Simplex Algorithm With Many Local Restarts
Hansen, Nikolaus
2009-01-01
International audience We benchmark the Nelder-Mead downhill simplex method on the noisefree BBOB-2009 testbed. A multistart strategy is applied on two levels. On a local level, at least ten restarts are conducted with a small number of iterations and reshaped simplex. On the global level independent restarts are launched until $10^5 D$ function evaluations are exceeded, for dimension $D\\ge20$ ten times less. For low search space dimensions the algorithm shows very good results on many fun...
Many worlds interpretation for double slit experiment
Yun, Zinkoo
2014-01-01
As is well known, the double slit experiment contains every key concepts of quantum mechanics such as phase effect, probability wave, quantum interference, quantum superposition. In this article, I will clarify the meaning of quantum superposition in terms of phase effect between states. After applying standard quantum theory, it leads to serious questions about the unitary process of an isolated system. It implies that non collapsing interpretations including many worlds may not be justified. This also could explain that there is no such boundary between classical and quantum domains.
The Many Faces of School Library Leadership
COATNEY, SHARON
2010-01-01
More than ever, it is vital that librarians demonstrate leadership skills that will reinforce their own value and that of their institutions. The Many Faces of School Library Leadership offers insights and practical suggestions for such leadership through 10 essays contributed by outstanding leaders in the field of school librarianship. ||The book covers leadership in curriculum and instruction, literacy, technology, intellectual freedom, staff development, and other equally critical areas. It discusses the breadth and depth of the leadership school librarians must provide to move the school l
Aspects of dual models many years ago
Corrigan, E
2008-01-01
In October 1969, almost forty years ago I started my three years as a graduate student in the Department of Applied Mathematics and Theoretical Physics, Cambridge. During the previous year, as was customary then, I took Part III of the Mathematics Tripos. This was a thorough grounding in many of the tools then useful in elementary particle theory. However, by today's standards, it was lacking in some respects, especially in the area of quantum field theory - the most notable omission being any mention of Yang-Mills gauge theory.
Nuclear, particle and many body physics
Morse, Philip M; Feshbach, Herman
2013-01-01
Nuclear, Particle and Many Body Physics, Volume II, is the second of two volumes dedicated to the memory of physicist Amos de-Shalit. The contributions in this volume are a testament to the respect he earned as a physicist and of the warm and rich affection he commanded as a personal friend. The book contains 41 chapters and begins with a study on the renormalization of rational Lagrangians. Separate chapters cover the scattering of high energy protons by light nuclei; approximation of the dynamics of proton-neutron systems; the scattering amplitude for the Gaussian potential; Coulomb excitati
THE MANY FACES OF CARING IN NURSING.
Farrow, Jennifer
2016-02-01
Nonverbal communication is essential with children. Nurses are challenged when answers to assessment questions include shoulder shrugs and descriptions of 'ouchies' and pain all over that feels 'bad.' Pediatric nursing requires creativity and eliciting expression of emotions nonverbally. One way our patients express themselves is through art therapy. The art therapist on our unit uses masks with children who choose not to express themselves with words. I chose to create a mask as sculpture to nonverbally share my values, feelings, and compassion, just like my pediatric patients. As I worked with the mask, many faces of nursing emerged. PMID:27062865
Many Putative Endocrine Disruptors Inhibit Prostaglandin Synthesis
DEFF Research Database (Denmark)
Kristensen, David M.; Skalkam, Maria L.; Audouze, Karine Marie Laure;
2011-01-01
Background: Prostaglandins (PGs) play key roles in development and maintenance of homeostasis of the adult body. Despite these important roles, it remains unclear whether the PG pathway is a target for endocrine disruption. However, several known endocrine disrupting compounds (EDCs) share a high...... of endocrine disruption. Results: We found that many known EDCs inhibit the PG pathway in a mouse Sertoli cell line and in human primary mast cells. The EDCs also reduced PG synthesis in ex vivo rat testis and it was correlated with a reduced testosterone production. The inhibition of PG synthesis occurs...
The many worlds interpretation of quantum mechanics
Dewitt, Bryce Seligman
2015-01-01
A novel interpretation of quantum mechanics, first proposed in brief form by Hugh Everett in 1957, forms the nucleus around which this book has developed. In his interpretation, Dr. Everett denies the existence of a separate classical realm and asserts the propriety of considering a state vector for the whole universe. Because this state vector never collapses, reality as a whole is rigorously deterministic. This reality, which is described jointly by the dynamical variables and the state vector, is not the reality customarily perceived; rather, it is a reality composed of many worlds. By vir
Many-Body Physics with Trapped Ions
Schneider, Christian; Schaetz, Tobias
2011-01-01
Direct experimental access to some of the most intriguing quantum phenomena is not granted due to the lack of precise control of the relevant parameters in their naturally intricate environment. Their simulation on conventional computers is impossible, since quantum behaviour arising with superposition states or entanglement is not efficiently translatable into the classical language. However, one could gain deeper insight into complex quantum dynamics by experimentally simulating the quantum behaviour of interest in another quantum system, where the relevant parameters and interactions can be controlled and robust effects detected sufficiently well. We report on the progress in experimentally simulating quantum many-body physics with trapped ions.
Many electron effects in semiconductor quantum dots
Indian Academy of Sciences (India)
R K Pandey; Manoj K Harbola; V Ranjan; Vijay A Singh
2003-01-01
Semiconductor quantum dots (QDs) exhibit shell structures, very similar to atoms. Termed as ‘artificial atoms’ by some, they are much larger (1 100 nm) than real atoms. One can study a variety of manyelectron effects in them, which are otherwise difficult to observe in a real atom. We have treated these effects within the local density approximation (LDA) and the Harbola–Sahni (HS) scheme. HS is free of the selfinteraction error of the LDA. Our calculations have been performed in a three-dimensional quantum dot. We have carried out a study of the size and shape dependence of the level spacing. Scaling laws for the Hubbard ‘’ are established.
Om: One tool for many (Indian) languages
Institute of Scientific and Technical Information of China (English)
GANAPATHIRAJU Madhavi; BALAKRISHNAN Mini; BALAKRISHNAN N.; REDDY Raj
2005-01-01
Many different languages are spoken in India, each language being the mother tongue of tens of millions of people.While the languages and scripts are distinct from each other, the grammar and the alphabet are similar to a large extent. One common feature is that all the Indian languages are phonetic in nature. In this paper we describe the development of a translit eration scheme Om which exploits this phonetic nature of the alphabet. Om uses ASCⅡ characters to represent Indian language alphabets, and thus can be read directly in English, by a large number of users who cannot read script in other Indian languages than their mother tongue. It is also useful in computer applications where local language tools such as email and chat are not yet available. Another significant contribution presented in this paper is the development of a text editor for Indian languages that integrates the Om input for many Indian languages into a word processor such as Microsoft WinWord(R). The text editor is also developed on Java(R) platform that can run on Unix machines as well. We propose this transliteration scheme as a possible standard for Indian language transliteration and keyboard entry.
Obesity: single house for many evils.
Kumar, Ashwini; Nayak, Bibhukalyan P; Kumar, Awanish
2016-12-01
World Health Organization (WHO) considers obesity as one of the fastest growing metabolic disorders other than diabetes. It is a complex interplay of lifestyle and associated genes. Obesity has been considered as a disease with multiple targets and very often compared in this sense with its sibling disease type 2 diabetes. The disease is pathology of the adipocytes and develops as a result of hypertrophy and hyperplasia of these cells, former being the major concern but its effects could be seen on various organs in the form of cardio-vascular disease, stroke, cancer, diabetes, sexual dysfunction, respiratory problems and many more. An increase in the lipid content of the adipocytes changes the physiology of these cells towards more inflammatory phenotype. The array of molecules or adipokines secreted by these cells varies in concentration and type among healthy and obese subjects. On one hand where adiponectin concentration decreases, the resistin concentration increases resulting in insulin resistance among many other adipokine related effects. Specifically, an obese person develops hyperlipidemia, insulin resistance, vascular blockage, sleep apnoea, cancer etc. This review is an attempt to focus, in detail, about obesity related complications. PMID:27600644
Quantum Statistical Entropy of Spherical Black Holes in Higher Dimensions
Institute of Scientific and Technical Information of China (English)
XU Dian-Yan
2000-01-01
The free energy and entropy of a general spherically symmetry black hole are calculated by quantum statistic method with brick wall model Two different kinds of approximation are used to calculate the number of states in transverse spatial space. The final results are approximately equal except a rational numerical constant. The formulas of free energy and entropy, evaluated by each one of the two different kinds of approximation, are the same except some numerical constants. The free energy and entropy are dependent on the spacetime dimensionsD. When D = 4, they reduce to the usual well known results.
Fractal dimension crossovers in turbulent passive scalar signals
Grossmann, Siegfried; Lohse, Detlef
1994-01-01
The fractal dimension $\\delta_g^{(1)}$ of turbulent passive scalar signals is calculated from the fluid dynamical equation. $\\delta_g^{(1)}$ depends on the scale. For small Prandtl (or Schmidt) number $Pr 1$ one gets a third, intermediate range in which the signal is extremely wrinkled and has $\\delta_g^{(1)}=2$. In that range the passive scalar structure function $D_\\theta(r)$ has a plateau. We calculate the $Pr$-dependence of the crossovers. Comparison with a numerical reduced wave vector s...
Dimensions of problem based learning
DEFF Research Database (Denmark)
Nielsen, Jørgen Lerche; Andreasen, Lars Birch
2013-01-01
The article contributes to the literature on problem based learning and problem-oriented project work, building on and reflecting the experiences of the authors through decades of work with problem-oriented project pedagogy. The article explores different dimensions of problem based learning such...... as the exploration of problems, the project method, online collaboration, and the dialogic nature of students’ working together. A special attention is given to the historical development and theoretical roots of problem-oriented project work in Denmark. The case to be explored will be the Masters...... programme in ICT and Learning (MIL). We discuss changes in the roles of the teachers as supervisors within this learning environment, and we explore the involvement of students as active participants and co-designers of how course and project activities unfold....
Kolmogorov Flow in Three Dimensions
Shebalin, John V.; Woodruff, Stephen L.
1996-01-01
A numerical study of the long-time evolution of incompressible Navier-Stokes turbulence forced at a single long-wavelength Fourier mode, i.e., a Kolmogorov flow, has been completed. The boundary conditions are periodic in three dimensions and the forcing is effected by imposing a steady, two-dimensional, sinusoidal shear velocity which is directed along the x-direction and varies along the z-direction. A comparison with experimental data shows agreement with measured cross-correlations of the turbulent velocity components which lie in the mean-flow plane. A statistical analysis reveals that the shear-driven turbulence studied here has significant spectral anisotropy which increases with wave number.
Keynote speech: Dimensions of Change
DEFF Research Database (Denmark)
Jørgensen, Kenneth Mølbjerg
2004-01-01
The presentation seeks to construct a framework for understanding knowledge and knowledge work. I argue that knowledge may be understood as a social construction of reality. I argue that people construct their reality by integrating four dimensions of reality: Facts, logic, values and communicati....... I argue that this framework leads to a new and critical understanding of the disciplines organizational learning and knowledge management. In particular I argue that these disciplines often contain their own image of work and identity, which may be a sharp contrast to extant work forms...... and identities. As such the work of these disciplines is often rather misplaced and it tends to be rather unsuccessful. I argue that we need to adjust knowledge and learning strategies to local circumstances in order to be more successful in creating new knowledge. The presentation has three parts. First I...
Human dimension of strategic partnerships
Directory of Open Access Journals (Sweden)
Petković Mirjana M.
2004-01-01
Full Text Available This paper aims to point to the widespread practice of neglecting behavioral aspects of different forms of fusions and integrations of enterprises that have emerged in the process of privatization through strategic partnerships with foreign companies among Serbian enterprises. The initial hypothesis in this paper is that the process of privatization, restructuring and transformation in Serbian enterprises cannot be completely successful and equally advantageous for all the subjects involved if there is no concern for human dimension of these processes. Without this concern there is a possibility for behavioral problems to arise, and the only way to resolve them is through post festum respecting and introducing elements that should never have been neglected in the first place. This paper refers to the phenomenon of collision of cultures and the ways of resolving it while forming strategic partnerships.
Quantum interest in two dimensions
Teo, E; Teo, Edward
2002-01-01
The quantum interest conjecture of Ford and Roman asserts that any negative-energy pulse must necessarily be followed by an over-compensating positive-energy one within a certain maximum time delay. Furthermore, the minimum amount of over-compensation increases with the separation between the pulses. In this paper, we first study the case of a negative-energy square pulse followed by a positive-energy one for a minimally coupled, massless scalar field in two-dimensional Minkowski space. We obtain explicit expressions for the maximum time delay and the amount of over-compensation needed, using a previously developed eigenvalue approach. These results are then used to give a proof of the quantum interest conjecture for massless scalar fields in two dimensions, valid for general energy distributions.
The spatial dimensions of innovation
DEFF Research Database (Denmark)
Lorentzen, Anne
2005-01-01
The paper discusseses the spatial dimensions of innovation in Polish manufacturing companies. The conceptual framework of the paper is an understanding of social networks as a potential resource of the company, whether they are internal or external. Whether the company benefits from the potential...... by the common perceptions, and the institutional infrastructure prevailing in the (local)society. In Poland the latter is closely connected with the process of transition since 1990. The paper reports from a study among Polish manufacturing companies. It categorises the types of innovation prevailing...... in the companies and detects the role of networks in the innovation process of the companies. To what extend do the companies draw on external networks, on what points of the innovation process are the networks involved, what kind of networks are involved, and not least, what are the spatial characteristics...
Psychological dimensions of Energy Conservation
Directory of Open Access Journals (Sweden)
Tonello, Graciela
2012-12-01
Full Text Available One of the most serious current environmental problems is the depletion of non renewable natural resources. The vast majority of our daily actions involve the consumption of energy and they increase the problem. Environmental psychology studies the psychological motivations that determine pro-ecological behaviour. In this context the aim of this review was to determine which psychological models and variables are better descriptors of residential energy conservation, comparing the predictive power of different models related to behaviour, residential consumption as well as to the acceptability of energy policies. Results suggest that energy saving is mainly linked to altruistic motivations, followed by egoistic reasons and in a minor way to environmental concerns. People would act according to these dimensions when contextual conditions are perceived as appropriate.
Robust large dimension terahertz cloaking
Liang, Dachuan; Han, Jiaguang; Yang, Yuanmu; Zhang, Shuang; Zhang, Weili
2011-01-01
Invisibility cloaking not only catches the human imagination, but also promises fascinating applications in optics and photonics. By manipulating electromagnetic waves with metamaterials, researchers have been able to realize electromagnetic cloaking in the microwave, terahertz and optical regimes. Nevertheless, the complex design and fabrication process, narrow bandwidth, and high intrinsic losses in the metamaterial-based cloaks have imposed intractable limitations on their realistic applications. Seeking new approaches to overcome these perceived disadvantages is in progress. Here by using uniform sapphire crystal, we demonstrate the first homogenous invisibility cloak functioning at terahertz frequencies. The terahertz invisibility device features a large concealed volume, low loss, and broad bandwidth. In particular, it is capable of hiding objects with a dimension nearly an order of magnitude larger than that of its lithographic counterpart, but without involving complex and time-consuming cleanroom pro...
Dimensions and Units in Electrodynamics
Hehl, F W; Hehl, Friedrich W; Obukhov, Yuri N
2004-01-01
We sketch the foundations of classical electrodynamics, in particular the transition that took place when Einstein, in 1915, succeeded to formulate general relativity. In 1916 Einstein demonstrated that, with a choice of suitable variables for the electromagnetic field, it is possible to put Maxwell's equation into a form that is covariant under general coordinate transformations. This unfolded, by basic contributions of Kottler, Cartan, van Dantzig, Schouten & Dorgelo, Toupin & Truesdell, and Post, to what one may call {\\em premetric classical electrodynamics.} This framework will be described shortly. An analysis is given of the physical dimensions involved in electrodynamics and subsequently the question of units addressed. It will be pointed out that these results are untouched by the generalization of classical to quantum electrodynamics (QED). We compare critically our results with those of {\\sl L.B. Okun} which he had presented at a recent conference.
Trading in Risk Dimensions (TRD)
Ingber, Lester
2007-01-01
Previous work, mostly published, developed two-shell recursive trading systems. An inner-shell of Canonical Momenta Indicators (CMI) is adaptively fit to incoming market data. A parameterized trading-rule outer-shell uses the global optimization code Adaptive Simulated Annealing (ASA) to fit the trading system to historical data. A simple fitting algorithm, usually not requiring ASA, is used for the inner-shell fit. An additional risk-management middle-shell has been added to create a three-shell recursive optimization/sampling/fitting algorithm. Portfolio-level distributions of copula-transformed multivariate distributions (with constituent markets possessing different marginal distributions in returns space) are generated by Monte Carlo samplings. ASA is used to importance-sample weightings of these markets. The core code, Trading in Risk Dimensions (TRD), processes Training and Testing trading systems on historical data, and consistently interacts with RealTime trading platforms at minute resolutions, but ...
Negative ion formation in lanthanide atoms: Many-body effects
Felfli, Z; Sokolovski, D
2016-01-01
Investigations of low-energy electron-scattering of the lanthanide atoms Eu, Nd, Tb, Tm demonstrate that electron-correlation effects and core polarization are the dominant fundamental many-body effects responsible for the formation of metastable states of negative ions. Ramsauer Townsend minima, shape resonances and binding energies of the resultant anions are identified and extracted from the elastic total cross sections calculated using the complex angular momentum method. The large discrepancy between the recently measured electron affinity of 0.116 and the previously measured value of 1.053 eV for Eu is resolved. Also, the previously measured electron affinities for Nd, Tb and Tm are reconciled and new values are extracted from the calculated total cross sections. The large electron affinities found here for these atoms, should be useful in negative ion nanocatalysis, including methane conversion to methanol without CO2 emission, with significant environmental impact.. The powerful complex angular moment...
Charge-optimized many-body (COMB) potential for zirconium
Noordhoek, Mark J.; Liang, Tao; Lu, Zizhe; Shan, Tzu-Ray; Sinnott, Susan B.; Phillpot, Simon R.
2013-10-01
An interatomic potential for zirconium is developed within the charge-optimized many-body (COMB) formalism. The potential correctly predicts the hexagonal close-packed (HCP) structure as the ground state with cohesive energy, lattice parameters, and elastic constants matching experiment well. The most stable interstitial position is the basal octahedral followed by basal split, in agreement with recent first principles calculations. Stacking fault energies within the prism and basal planes satisfactorily match first principles calculations. A tensile test using nanocrystalline zirconium exhibits both prismatic {1 0 1bar 0} slip and pyramidal {1 1 2bar 2} slip, showing the model is capable of reproducing the mechanical deformation modes observed in experiments.
Many electron correlations in stage-1 graphene intercalation compounds
Energy Technology Data Exchange (ETDEWEB)
Acharya, Sidharth, E-mail: AcharyaSidharth19@yahoo.in; Sharma, Raman, E-mail: sramanb70@mailcity.com [Department of Physics Himachal Pradesh University, Shimla, Shimla-171005 (India)
2015-05-15
Many electron correlations in stage-1 graphene intercalation compounds (GICs) are studied in generalized-random-phase-approximation. With this approximation, we are able to study short range exchange and correlation effects in GICs. These exchange correlations leads to BCS superconducting states in which one electron correlates with another via its correlation hole to form a stable pair of electrons known as Cooper pair. Cooper pair energies are calculated as the excitations in S(q,ω) following a method similar to exciton energy calculations. Short range effects governing local field correction G(q,ω) are studied for all wave vectors and frequencies. We have found a reasonable agreement between our results and the earlier theoretical results.
Stability of extra dimensions in the inflating early universe
Energy Technology Data Exchange (ETDEWEB)
Wieck, Clemens
2015-08-15
Cosmic inflation is an attractive paradigm to explain the initial conditions of the universe. It can be conveniently described by the dynamics of a single scalar field within N=1 supergravity. Due to the high energy scale during the inflationary epoch, which is favored by recent observations of the cosmic microwave background radiation, and the flatness of the inflaton potential it is necessary to consider inflation in the context of a UV-complete theory like string theory. To this end, we study the effects of moduli stabilization on inflation models in supergravity, focussing on Kahler moduli in type IIB string theory which govern the size of extra dimensions. For generic models of F-term inflation we calculate back-reaction terms by integrating out the moduli at a high energy scale. When the moduli are stabilized supersymmetrically, all effects decouple in the limit of very heavy moduli. The corrections, however, may be sizeable for realistic moduli masses above the Hubble scale and affect the predicted observables of many models like chaotic inflation and hybrid inflation. If, on the other hand, moduli stabilization entails spontaneous supersymmetry breaking, there are non-decoupling effects like soft mass terms for the inflaton. By the example of chaotic inflation we show that a careful choice of parameters and initial conditions is necessary to reconcile large-field inflation with popular moduli stabilization schemes like KKLT stabilization or the Large Volume Scenario. Furthermore, we study the interplay of moduli stabilization and D-term inflation. If inflation is driven by a constant Fayet-Iliopoulos term, the back-reaction decouples but the gravitino mass in the vacuum is surprisingly constrained. For a field-dependent Fayet-Iliopoulos term associated with an anomalous U(1) symmetry we discuss a number of obstructions to realizing inflation. Moreover, we propose a way to evade them using a new mechanism for supersymmetric moduli stabilization with world
Stability of extra dimensions in the inflating early universe
International Nuclear Information System (INIS)
Cosmic inflation is an attractive paradigm to explain the initial conditions of the universe. It can be conveniently described by the dynamics of a single scalar field within N=1 supergravity. Due to the high energy scale during the inflationary epoch, which is favored by recent observations of the cosmic microwave background radiation, and the flatness of the inflaton potential it is necessary to consider inflation in the context of a UV-complete theory like string theory. To this end, we study the effects of moduli stabilization on inflation models in supergravity, focussing on Kahler moduli in type IIB string theory which govern the size of extra dimensions. For generic models of F-term inflation we calculate back-reaction terms by integrating out the moduli at a high energy scale. When the moduli are stabilized supersymmetrically, all effects decouple in the limit of very heavy moduli. The corrections, however, may be sizeable for realistic moduli masses above the Hubble scale and affect the predicted observables of many models like chaotic inflation and hybrid inflation. If, on the other hand, moduli stabilization entails spontaneous supersymmetry breaking, there are non-decoupling effects like soft mass terms for the inflaton. By the example of chaotic inflation we show that a careful choice of parameters and initial conditions is necessary to reconcile large-field inflation with popular moduli stabilization schemes like KKLT stabilization or the Large Volume Scenario. Furthermore, we study the interplay of moduli stabilization and D-term inflation. If inflation is driven by a constant Fayet-Iliopoulos term, the back-reaction decouples but the gravitino mass in the vacuum is surprisingly constrained. For a field-dependent Fayet-Iliopoulos term associated with an anomalous U(1) symmetry we discuss a number of obstructions to realizing inflation. Moreover, we propose a way to evade them using a new mechanism for supersymmetric moduli stabilization with world
Directory of Open Access Journals (Sweden)
Mohammad Reza Hamidizadeh
2012-01-01
Full Text Available Today, many businesses are facing a crisis of confidence with rising of uncontrolled prices and unemployment. The businesses can reduce this mistrust by creating competitive advantage through brand personality and moral qualities in the market. Therefore, this research aims to address, first, the relationship between personality dimensions and brand equity at one level model, and then, the second-level model the role of Ethical Attributes moderating. The statistical population is to include all customers the Shahrvand chain store in Tehran. The required rate sample was determined 384 samples, initially using table "Krejcie and Morgan, and Then, required rate was calculated in each store, according to the five areas of Tehran and a number of stores in each region. Finally, we succeeded to collect 395 questionnaires and the data base was used for analysis. In order to analyze the questionnaire data and hypotheses test, this research has made use of tests of descriptive, R2 change and structural equation. The results show that, two dimensions of "dynamics and responsibility" have a significant effect on brand equity; and Ethical Attributes play a role moderating on relationship of Responsibility and Activity with Brand equity. But, only, it is significant on the relationship between Activity and Brand equity.
Directory of Open Access Journals (Sweden)
Mohammad Reza Hamidizadeh
2012-12-01
Full Text Available Today, many businesses are facing a crisis of confidence with rising of uncontrolled prices and unemployment. The businesses can reduce this mistrust by creating competitive advantage through brand personality and moral qualities in the market. Therefore, this research aims to address, first, the relationship between personality dimensions and brand equity at one level model, and then, the second-level model the role of Ethical Attributes moderating. The statistical population is to include all customers the Shahrvand chain store in Tehran. The required rate sample was determined 384 samples, initially using table "Krejcie and Morgan, and Then, required rate was calculated in each store, according to the five areas of Tehran and a number of stores in each region. Finally, we succeeded to collect 395 questionnaires and the data base was used for analysis. In order to analyze the questionnaire data and hypotheses test, this research has made use of tests of descriptive, R2 change and structural equation. The results show that, two dimensions of "dynamics and responsibility" have a significant effect on brand equity and Ethical Attributes play a role moderating on relationship of Responsibility and Activity with Brand equity. But, only, it is significant on the relationship between Activity and Brand equity.
Study of dose calculation on breast brachytherapy using prism TPS
Energy Technology Data Exchange (ETDEWEB)
Fendriani, Yoza; Haryanto, Freddy [Nuclear Physics and Biophysics Research Division, FMIPA Institut Teknologi Bandung, Physics Buildings, Jl. Ganesha 10, Bandung 40132 (Indonesia)
2015-09-30
PRISM is one of non-commercial Treatment Planning System (TPS) and is developed at the University of Washington. In Indonesia, many cancer hospitals use expensive commercial TPS. This study aims to investigate Prism TPS which been applied to the dose distribution of brachytherapy by taking into account the effect of source position and inhomogeneities. The results will be applicable for clinical Treatment Planning System. Dose calculation has been implemented for water phantom and CT scan images of breast cancer using point source and line source. This study used point source and line source and divided into two cases. On the first case, Ir-192 seed source is located at the center of treatment volume. On the second case, the source position is gradually changed. The dose calculation of every case performed on a homogeneous and inhomogeneous phantom with dimension 20 × 20 × 20 cm{sup 3}. The inhomogeneous phantom has inhomogeneities volume 2 × 2 × 2 cm{sup 3}. The results of dose calculations using PRISM TPS were compared to literature data. From the calculation of PRISM TPS, dose rates show good agreement with Plato TPS and other study as published by Ramdhani. No deviations greater than ±4% for all case. Dose calculation in inhomogeneous and homogenous cases show similar result. This results indicate that Prism TPS is good in dose calculation of brachytherapy but not sensitive for inhomogeneities. Thus, the dose calculation parameters developed in this study were found to be applicable for clinical treatment planning of brachytherapy.
Publication Ethics: Many Facets, Collaboration Required
Directory of Open Access Journals (Sweden)
Viroj Wiwanitkit
2013-05-01
Full Text Available Sir, the recent publication on “Publication Ethics” is very interesting (1. The article by Fazly Bazzaz and Sadeghi demonstrated many interesting cases of misconducts. Indeed, the misconducts can be seen in many ways. As mentioned in the present publication, both author and editor can perform publication misconducts. Nevertheless, the problem has many more facets. Sometimes, the misconducts are generated by the third parties. For example, the publisher can perform publication misconduct. In fact, the editor takes the role in control of the materials to be published in the journal. However, the publisher sometimes interferes with the process. Some unethical publication can be seen in some “predator” online publisher. “Pay then publish” without control of its quality can be seen (see also http://www.nature.com/news/predatory-publishers-are-corrupting-open-access-1.11385 and scholarlyoa.com/2012/12/06/bealls-list-of-edatory-publishers-2013. In the present era of rapidly increased number of open access journal, this problem is expected to increase. Another example is the criminal case of “one disguising to be the other person” to perform misconduct aiming at discrediting or destroying others. An interesting case was previously published in Hepatitis Monthly; an author performed plagiarized articles behind the name of another person and finally was charged by the IT investigation (2. Finally, the institute sometimes also performs misconduct. This can be supporting of their members who perform scientific misconduct by acts which do not correspond to the problem (this problem is usually seen in the problematic case generated by senior faculties or administrators, dealing with publisher to “buy” supplementary volume for publication of the works
Wax Precipitation Modeled with Many Mixed Solid Phases
DEFF Research Database (Denmark)
Heidemann, Robert A.; Madsen, Jesper; Stenby, Erling Halfdan;
2005-01-01
The behavior of the Coutinho UNIQUAC model for solid wax phases has been examined. The model can produce as many mixed solid phases as the number of waxy components. In binary mixtures, the solid rich in the lighter component contains little of the heavier component but the second phase shows......-temperature and low-temperature forms, are pure. Model calculations compare well with the data of Pauly et al. for C18 to C30 waxes precipitating from n-decane solutions. (C) 2004 American Institute of Chemical Engineers....
[How many subjects do I need to power my study?].
Muñoz Navarro, Sergio R
2014-01-01
The article presents a tool that helps answer the question How many subjects do I need to power my study? We show how to determine sample size in observational epidemiological studies and provide examples of application using the statistical package Epidat, which is a shareware program developed under the auspices of the Pan American Health Organization, the Galician Board of Health and the University CES of Colombia. Examples of calculation of sample size for prevalence studies (cross-sectional), case-control studies and cohort studies are given. PMID:25354214
Prediction of quantum many-body chaos in protactinium atom
Viatkina, A V; Flambaum, V V
2016-01-01
Energy level spectrum of protactinium atom (Pa, Z=91) is simulated with a CI calculation. Levels belonging to the separate manifolds of a given total angular momentum and parity $J^\\pi$ exhibit distinct properties of many-body quantum chaos. Moreover, an extremely strong enhancement of small perturbations takes place. As an example, effective three-electron interaction is investigated and found to play a significant role in the system. Chaotic properties of the eigenstates allow one to develop a statistical theory and predict probabilities of different processes in chaotic systems.
Probing quantum many-body dynamics in nuclear systems
International Nuclear Information System (INIS)
Quantum many-body nuclear dynamics is treated at the mean-field level with the time-dependent Hartree-Fock (TDHF) theory. Low-lying and high-lying nuclear vibrations are studied using the linear response theory. The fusion mechanism is also described for light and heavy systems. The latter exhibit fusion hindrance due to quasi-fission. Typical characteristics of quasi-fission, such as contact time and partial symmetrisation of the fragments mass in the exit channel, are reproduced by TDHF calculations. The (multi-)nucleon transfer at sub-barrier energies is also discussed. (authors)
How many subjects do I need to power my study?
Directory of Open Access Journals (Sweden)
Sergio R. Muñoz Navarro
2014-07-01
Full Text Available The article presents a tool that helps answer the question “How many subjects do I need to power my study? We show how to determine sample size in observational epidemiological studies and provide examples of application using the statistical package Epidat, which is a shareware program developed under the auspices of the Pan American Health Organization, the Galician Board of Health and the University CES of Colombia. Examples of calculation of sample size for prevalence studies (cross-sectional, case-control studies and cohort studies are given.
Probing quantum many-body dynamics in nuclear systems
Simenel, C; Hinde, D J; Kheifets, A; Wakhle, A
2013-01-01
Quantum many-body nuclear dynamics is treated at the mean-field level with the time-dependent Hartree-Fock (TDHF) theory. Low-lying and high-lying nuclear vibrations are studied using the linear response theory. The fusion mechanism is also described for light and heavy systems. The latter exhibit fusion hindrance due to quasi-fission. Typical characteristics of quasi-fission, such as contact time and partial symmetrisation of the fragments mass in the exit channel, are reproduced by TDHF calculations. The (multi-)nucleon transfer at sub-barrier energies is also discussed.
The Telephone: An Invention with Many Fathers
Energy Technology Data Exchange (ETDEWEB)
Brenni, Paolo (CNR-FST-IMSS, Florence, Italy)
2008-10-01
The names of A.G. Bell, A. Meucci, P.Reis, E. Gray, just to mention the most important ones, are all connected with the invention of the telephone. Today, the Italian inventor A. Meucci is recognized as being the first to propose a working prototype of the electric telephone. However, for a series of reasons his strenuous efforts were not rewarded. I will not repeat here the endless and complex disputes about the 'real father' of the telephone. From an historical point of view it is more interesting to understand why so many individuals from different backgrounds conceived of a similar apparatus and why most of these devices were simply forgotten or just remained laboratory curiosities. The case of the development of the telephone is an emblematic and useful example for better understanding the intricate factors which are involved in the birth of an invention and reasons for its success and failure.
Interferometric probes of many-body localization.
Serbyn, M; Knap, M; Gopalakrishnan, S; Papić, Z; Yao, N Y; Laumann, C R; Abanin, D A; Lukin, M D; Demler, E A
2014-10-01
We propose a method for detecting many-body localization (MBL) in disordered spin systems. The method involves pulsed coherent spin manipulations that probe the dephasing of a given spin due to its entanglement with a set of distant spins. It allows one to distinguish the MBL phase from a noninteracting localized phase and a delocalized phase. In particular, we show that for a properly chosen pulse sequence the MBL phase exhibits a characteristic power-law decay reflecting its slow growth of entanglement. We find that this power-law decay is robust with respect to thermal and disorder averaging, provide numerical simulations supporting our results, and discuss possible experimental realizations in solid-state and cold-atom systems. PMID:25325656
Many-body Physics of Rydberg Polaritons
Edelman, Alexander; Littlewood, Peter
2014-03-01
Electromagnetically induced transparency (EIT) in cold dense atomic gasses with Rydberg states in has attracted considerable interest as a means of realizing strong nonlinear photon-photon interactions. The coherent light-matter coupling provided by the EIT medium combined with interactions between Rydberg states whose strength and shape can be engineered provide a parameter space with rich phenomenology including photon bound states and spatially ordered structures. Past theoretical treatments of these systems have relied on equations of motion to predict dynamics in particular limits. Here we present progress towards a full many-body path integral description that considers interaction effects beyond the Dicke model as well as the intrinsically non-equilibrium nature of the system, and explore a tentative phase diagram.
Only one health, and so many omics.
Pećina-Šlaus, Nives; Pećina, Marko
2015-01-01
The development of new approaches based on wide profiling methods in studying biological and medical systems is bringing large amounts of data on a daily basis. The causes of complex diseases have been directed to the genome examination bringing formidable knowledge. We can study genome, but also proteome, exome, transcriptome, epigenome, metabolome, and newcomers too such as microbiome, connectome and exposome. The title of this editorial is paraphrasing the famous saying of Victor Schlichter from Buenos Aires children hospital in Argentina who said "How unfair! Only one health, and so many diseases". Today there is indeed a whole lot of omics. We think that we are lucky to have all the omics possible, but we also wanted to stress the importance of future holistic approach in integrating the knowledge omics has rewarded us. PMID:26101467
Probabilistic Logic: Many-valuedness and Intensionality
Majkic, Zoran
2011-01-01
The probability theory is a well-studied branch of mathematics, in order to carry out formal reasoning about probability. Thus, it is important to have a logic, both for computation of probabilities and for reasoning about probabilities, with a well-defined syntax and semantics. Both current approaches, based on Nilsson's probability structures/logics, and on linear inequalities in order to reason about probabilities, have some weak points. In this paper we have presented the complete revision of both approaches. We have shown that the full embedding of Nilsson'probabilistic structure into propositional logic results in a truth-functional many-valued logic, differently from Nilsson's intuition and current considerations about propositional probabilistic logic. Than we have shown that the logic for reasoning about probabilities can be naturally embedded into a 2-valued intensional FOL with intensional abstraction, by avoiding current ad-hoc system composed of two different 2-valued logics: one for the classica...
CIME School on Quantum Many Body Systems
Rivasseau, Vincent; Solovej, Jan Philip; Spencer, Thomas
2012-01-01
The book is based on the lectures given at the CIME school "Quantum many body systems" held in the summer of 2010. It provides a tutorial introduction to recent advances in the mathematics of interacting systems, written by four leading experts in the field: V. Rivasseau illustrates the applications of constructive Quantum Field Theory to 2D interacting electrons and their relation to quantum gravity; R. Seiringer describes a proof of Bose-Einstein condensation in the Gross-Pitaevski limit and explains the effects of rotating traps and the emergence of lattices of quantized vortices; J.-P. Solovej gives an introduction to the theory of quantum Coulomb systems and to the functional analytic methods used to prove their thermodynamic stability; finally, T. Spencer explains the supersymmetric approach to Anderson localization and its relation to the theory of random matrices. All the lectures are characterized by their mathematical rigor combined with physical insights.
Many diseases, one model of care?
Directory of Open Access Journals (Sweden)
Tit Albreht
2016-02-01
Full Text Available Abstract This article has been corrected. See J Comorbidity 2016;6(1:33. http://dx.doi.org/joc.2016.6.78. Patients with multiple chronic conditions (multimorbidity have complex and extensive health and social care needs that are not well served by current silo-based models of care. A lack of integration between care providers often leads to fragmented, incomplete, and ineffective care, leaving many patients overwhelmed and unable to navigate their way towards better health outcomes. In planning for the future, healthcare policies and models of care are required that cater for the complex needs of patients with multimorbidity and that deliver coordinated care that is patient-centred and focused on disease prevention, multidisciplinary teamwork and shared decision-making, and on empowering patients to self-manage. Salient lessons can be learnt from the work undertaken at a European and national level to develop care models in cancer and diabetes – two complex and often co-occurring conditions requiring coordinated long-term care. Innovative work is also underway in many European countries aimed at improving the integration of care for people with multimorbidity, resulting in more efficient and cost-effective health outcomes. This article reviews some of the most innovative programmes that have been initiated across and within Europe with the aim of improving the way care is delivered to people with complex and multiple long-term conditions. This work provides a foundation upon which to build better, more effective models of care for people with multimorbidity. Journal of Comorbidity 2016;6(1:12–20
There are many barriers to species' migrations
Directory of Open Access Journals (Sweden)
Kenneth J Feeley
2014-06-01
Full Text Available Temperature-change trajectories are being used to identify the geographic barriers and thermal ‘cul-de-sacs’ that will limit the ability of many species to track climate change by migrating. We argue that there are many other potential barriers to species’ migrations. These include stable ecotones, discordant shifts in climatic variables, human land use, and species’ limited dispersal abilities. To illustrate our argument, for each 0.5° latitude/longitude grid cell of the Earth’s land surface, we mapped and tallied the number of cells for which future (2060–2080 climate represents an analog of the focal cell’s current climate. We compared results when only considering temperature with those for which both temperature and total annual precipitation were considered in concert. We also compared results when accounting for only geographic barriers (no cross-continental migration with those involving both geographic and potential ecological barriers (no cross-biome migration. As expected, the number of future climate analogs available to each pixel decreased markedly with each added layer of complexity (e.g. the proportion of the Earth’s land surface without any available future climate analogs increased from 3% to more than 36% with the inclusion of precipitation and ecological boundaries. While including additional variables can increase model complexity and uncertainty, we must strive to incorporate the factors that we know will limit species’ ranges and migrations if we hope to predict the effects of climate change at a high-enough degree of accuracy to guide management decisions.
Molecular transport in the language of many-body states
Galperin, Michael
2009-03-01
Recent advancements in experimental techniques at nanoscale caused a surge in research of transport through molecular junctions. Nonlinearity of current-voltage characteristic at resonance makes this regime particularly important for potential molecular based memory, switchers and logic devices. One of important differences of molecular junctions (compared e.g. to semiconductor QDs) is sensitivity of electronic and vibrational structure of the junction to oxidation/reduction of the molecule. This implies necessity of treating the transport at resonance in the language of molecular states rather than single particle orbitals. The latter are the choice of majority of available ab initio approaches. We consider two possible schemes capable of incorporating isolated molecule (many-body) states as a basis for transport calculations. The schemes utilize Hubbard operators for description of single electron transitions between many-body states and go beyond previously proposed scattering theory and standard quantum master equation approaches.
Many-Body Theory of Atomic Transitions
Holmes, Charles Potter
This dissertation presents a systematic approach to the derivation of transition widths and cross sections for atomic radiative and/or nonradiative processes. By applying the transition theory of Goldberger and Watson ^1, all transition properties are derived from proper solutions of the time-dependent Schrodinger equation. The focus is on situations where initial and final wave functions are nonorthogonal functions that belong to different self-consistent fields. This approach is particularly useful in the treatment of ionizing transitions where the outgoing free electron sees a different atomic potential from that of the initial bound state. Transition amplitudes are expressed as perturbation expansions in which singularities have been removed algebraically. These singularities are due to states which are degenerate with the initial and final states and represent the competing transition channels. The perturbation expansions show clearly the role of the nonorthogonality of the participating states leading to terms representing "shake" processes competing with higher-order electron correlation processes. Transition amplitudes including all second-order processes, are derived for the following transitions: X-ray, Auger, photoionization, radiative recombination, dielectronic recombination, radiative -Auger. Comparisons are made with the expressions frequently used by other workers. Using a Hartree-Fock-Slater model K- and L-shell X-ray and Auger transition widths are calculated for the range 5 Z Theory, (John Wiley & Sons, New York, 1964), Chapter 8, page 424.
NUMERICAL ANALYSES OF THE UNDERGROUND EXPLOITATION OF DIMENSION STONE
1996-01-01
Underground exploitation of dimension stone is spreading lately for three main reasons; economy, organisation and environment. Moreover, underground openings can be used for many purposes. Underground exploitation is different from surface quarrying only in the first stage, the removal of top slice, descending slices are worked as in conventional quarries. In underground stone quarries, stability problems require adequate studies in order to avoid expensive artificial support measures, ...
Rugae dimensions and their significance in forensic dentistry
Sanjayagouda B Patil; Manashvini S Patil; B R Smita; Kavyashree G Hebbar
2016-01-01
Background: The palatal rugae are the ridges situated in the anterior part of the palatal mucosa, are unique to each individual, and can establish individual's identity. Aims: To establish the reliability of using the palatal rugae dimensions in identifying the different ethnic groups. Settings and Design: Many studies have established the reliability of using the palatal rugae patterns in identifying the different ethnic groups. However, no studies have been reported in the English language ...
Thermodynamics of many-band superconductors
International Nuclear Information System (INIS)
In the present thesis the microscopical properties of the superconducting state of MgCNi3, MgB2, and some rare earth-transition metal borocarbides are studied by means of measurements of the specific heat. Furthermore the frequency spectrum of the lattice vibrations is estimated. The energy gap of the superconducting state can be determined from the specific heat of the superconducting state, which yields as like as the upper critical mafnetic field Hc2(0) hints on the electron-phonon coupling. From the analysis of these results and the comparison with results from transport measurements as well as the tunnel and point-contact spectroscopy can be concluded, how far the BCS model of superconductivity must be modified in order to be able to describe the superconducting state of the studied compounds. Studies on MgCNi3, which lies near a magnetic instability, show that occurring magnetic fluctuations have a bisection of the superconducting transition temperature TC as consequence. The under this aspect relatively high value of TC=7 K is a consequence of strong electron-phonon coupling, which is essentailly carried by nickel vibrations stabilized by carbon. A for the first time observed distinct anomaly in the specific heat of the classical many-band superconductor MgB2 (here with pure 10B) at about Tc/4=10 K can be understood by means of a two-band model for the case of especially weak coupling between both bands. The analysis of the specific heat of the superconducting phase of the non-magnetic rare earth-nickel borocarbide YNi2B2C and LuNi2B2C leads to the conclusion thet visible effects of the many-band electron system are dependent on the mass on the position both of the rare earth and the transition metal. The signal of the superconducting phase transformation visible in the specific heat of the antiferromagnetic HoNi2B2C is smaller than expected
Genomic evaluations with many more genotypes
Directory of Open Access Journals (Sweden)
Wiggans George R
2011-03-01
Full Text Available Abstract Background Genomic evaluations in Holstein dairy cattle have quickly become more reliable over the last two years in many countries as more animals have been genotyped for 50,000 markers. Evaluations can also include animals genotyped with more or fewer markers using new tools such as the 777,000 or 2,900 marker chips recently introduced for cattle. Gains from more markers can be predicted using simulation, whereas strategies to use fewer markers have been compared using subsets of actual genotypes. The overall cost of selection is reduced by genotyping most animals at less than the highest density and imputing their missing genotypes using haplotypes. Algorithms to combine different densities need to be efficient because numbers of genotyped animals and markers may continue to grow quickly. Methods Genotypes for 500,000 markers were simulated for the 33,414 Holsteins that had 50,000 marker genotypes in the North American database. Another 86,465 non-genotyped ancestors were included in the pedigree file, and linkage disequilibrium was generated directly in the base population. Mixed density datasets were created by keeping 50,000 (every tenth of the markers for most animals. Missing genotypes were imputed using a combination of population haplotyping and pedigree haplotyping. Reliabilities of genomic evaluations using linear and nonlinear methods were compared. Results Differing marker sets for a large population were combined with just a few hours of computation. About 95% of paternal alleles were determined correctly, and > 95% of missing genotypes were called correctly. Reliability of breeding values was already high (84.4% with 50,000 simulated markers. The gain in reliability from increasing the number of markers to 500,000 was only 1.6%, but more than half of that gain resulted from genotyping just 1,406 young bulls at higher density. Linear genomic evaluations had reliabilities 1.5% lower than the nonlinear evaluations with 50
Inexpensive Implementation of Many Strain Gauges
Berkun, Andrew C.
2010-01-01
It has been proposed to develop arrays of strain gauges as arrays of ordinary metal film resistors and associated electronic readout circuitry on printed circuit boards or other suitable substrates. This proposal is a by-product of a development of instrumentation utilizing metal film resistors on printed-circuit boards to measure temperatures at multiple locations. In the course of that development, it was observed that in addition to being sensitive to temperature, the metal film resistors were also sensitive to strains in the printed-circuit boards to which they were attached. Because of the low cost of ordinary metal film resistors (typically strain gauges, possibly concentrated in small areas. For example, such an array could be designed for use as a computer keyboard with no moving parts, as a device for sensing the shape of an object resting on a surface, or as a device for measuring strains at many points on a mirror, a fuel tank, an airplane wing, or other large object. Ordinarily, the effect of strain on resistance would be regarded as a nuisance in a temperature-measuring application, and the effect of temperature on resistance would be regarded as a nuisance in a strain-measuring application. The strain-induced changes in resistance of the metal film resistors in question are less than those of films in traditional strain gauges. The main novel aspect of present proposal lies in the use of circuitry affording sufficient sensitivity to measure strain plus means for compensating for the effect of temperature. For an array of metal film resistors used as proposed, the readout circuits would include a high-accuracy analog-to-digital converter fed by a low noise current source, amplifier chain, and an analog multiplexer chain. Corrections would be provided by use of high-accuracy calibration resistors and a temperature sensor. By use of such readout circuitry, it would be possible to read the resistances of as many as 100 fixed resistors in a time interval
Multilayer optical calculations
Byrnes, Steven J
2016-01-01
When light hits a multilayer planar stack, it is reflected, refracted, and absorbed in a way that can be derived from the Fresnel equations. The analysis is treated in many textbooks, and implemented in many software programs, but certain aspects of it are difficult to find explicitly and consistently worked out in the literature. Here, we derive the formulas underlying the transfer-matrix method of calculating the optical properties of these stacks, including oblique-angle incidence, absorption-vs-position profiles, and ellipsometry parameters. We discuss and explain some strange consequences of the formulas in the situation where the incident and/or final (semi-infinite) medium are absorptive, such as calculating $T>1$ in the absence of gain. We also discuss some implementation details like complex-plane branch cuts. Finally, we derive modified formulas for including one or more "incoherent" layers, i.e. very thick layers in which interference can be neglected. This document was written in conjunction with ...
[Tissue grafts: an activity concerning many patients].
Loty, B
1997-11-15
Tissue allografts mainly include corneas, bone (and cartilage, tendon, ligament, aponevrosis), skin, vessels and cardiac valves. All these grafts have been widely used for many years and were the subject of a large number of experimental and clinical studies. The different steps allowing the obtention of different tissue allografts have in fact a common organization through tissue procurement and banking activities. Tissue banks have a central situation ensuring security, safety, traceability and distribution of tissues. Appropriate organization of the banks, and respect of high level standards are thus mandatory. Tissue transplantation activity in France has been studied through national surveys: they concern more than 600 hospitals and clinics, and grafts procured in France (excluding imported allografts) are around 15,000 a year. Precise regulation implied by the bioethical law published in 1994 and homogeneous organization of the activity allow the use of stringent and regularly updated standards, allowing the distribution to the patients of safe grafts procured in ethical conditions. The actual shortage of tissue allografts in France implies increasing procurement through a better organization of retrieval in hospitals and clinics and donation promotion. PMID:9501596
ECRH in LDX with Many Microwave Frequencies
Woskov, P.; Kesner, J.; Michael, P.; Garnier, D.; Mauel, M.; Davis, M.
2010-11-01
The large magnetic field range from 0.007 to 3.2 Tesla on closed flux surfaces around the LDX floating coil makes LDX uniquely capable of using many frequencies for electron cyclotron resonance heating (ECRH) to breakdown, build up, and sustain a core plasma. There are five sources installed with a combined injected power of 27 kW: two 2.45 GHz magnetrons at 2.5 and 1.9 kW, a 6.4 GHz, 2.5 kW klystron, a 10.5 GHz, 10 kW klystron, and a 28 GHz, 10 kW gyrotron. With all sources operating, D2 plasma density has increased to new highs near 10^18 m-3. Modeling with natural profiles shows strong ECRH absorption localized to discreet toroidal rings, each encompassing the plasma profile, that are located more inward with frequency. The relative size of the launched ECRH patterns to the absorption regions requires reflective trapping for complete absorption. Experimental observations show that higher frequencies are more efficient at generating density and lower frequencies are better at generating stored energy and energetic electrons.
Diphoton resonance from a warped extra dimension
Bauer, Martin; Hörner, Clara; Neubert, Matthias
2016-07-01
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with {O} (1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the Sto γ γ, W W,ZZ,Zγ, toverline{t} and dijet decay rates. We find that the S → Zγ decay mode is strongly suppressed, such that Br( S → Zγ) /Br( S → γγ) boson is solved in analogy with the Higgs boson by localizing it near the infrared brane. The infinite sums over the Kaluza-Klein towers of fermion states converge and can be calculated in closed form with a remarkably simple result. Reproducing the observed pp → S → γγ signal requires Kaluza-Klein masses in the multi-TeV range, consistent with bounds from flavor physics and electroweak precision observables.
The external dimension of the Spanish transition
Directory of Open Access Journals (Sweden)
Charles T. Powell
1993-07-01
Full Text Available The author intends to go beyond the unanimous opinion that the processes of political transition must be explained, almost exclusively, in terms of national forces and calculations. In the case of the Spanish transition he intends to demonstrate how thestrategies of the national actors (crown, government and parties were moulded largely by the pressure of regulations and structures drawn up outside its frontiers. Firstly, by the United States’ discreet support (always putting forward first her strategic interests of the political evolution whilst it did not put in danger the Spanish contribution to the western defensive system (while the USSR hardly played any role. The Spanish transition did not offer a threat to the alliance system from the beginning and with which the result was practically guaranteed. The European governments for their part, worried least about security and more about the political dimension pressurizing the regime and supporting the leaders of the democratic opposition more and more. The European institutions, withtheir veto, ended up legitimizing the Spanish process of democratization while the different Internationals came together and helped their coreligionists in Spain. Their political and diplomatic pressure were complemented, with the paradigm in the case of PSOE, with the contribution of means and resources by the political foundations, largely German, whose highly visible participation did not lessen the credibiity of those it protected.
Exploring extra dimensions with scalar waves
Jones-Smith, Katherine; Verostek, Michael
2016-01-01
This paper provides a pedagogical introduction to the physics of extra dimensions focussing on the ADD, Randall-Sundrum and DGP models. In each of these models, the familiar particles and fields of the standard model are assumed to be confined to a four dimensional space-time called the brane; the brane is a slice through a higher dimensional space-time called the bulk. The geometry of the ADD, Randall-Sundrum and DGP space-times is described and the relation between Randall-Sundrum and Anti-de-Sitter space-time is explained. The necessary differential geometry background is introduced in an appendix that presumes no greater mathematical preparation than multivariable calculus. The ordinary wave equation and the Klein-Gordon equation are briefly reviewed followed by an analysis of the propagation of scalar waves in the bulk in all three extra-dimensional models. We also calculate the scalar field produced by a static point source located on the brane for all three models. For the ADD and Randall-Sundrum model...
Scaling and universality in two dimensions
DEFF Research Database (Denmark)
Bellotti, Filipe Furlan; Frederico, T.; Yamashita, M. T.;
2011-01-01
and exhibit the results as universal curves. In particular, we show that the three-body system can have any number of stable bound states. When the mass ratio of the distinct to identical particles is greater than 0.22, we find that at most two stable bound states exist, while for two heavy and one light mass......The momentum space zero-range model is used to investigate universal properties of three interacting particles confined to two dimensions. The pertinent equations are first formulated for a system of two identical and one distinct particle and the two different two-body subsystems are characterized...... by two-body energies and masses. The three-body energy in units of one of the two-body energies is a universal function of the other two-body energy and the mass ratio. We derive convenient analytical formulae for calculations of the three-body energy as a function of these two independent parameters...
Dimension of a fractal streamer structure
Lehtinen, Nikolai G.; Østgaard, Nikolai
2015-04-01
Streamer corona plays an important role in formation of leader steps in lightning. In order to understand its dynamics, the streamer front velocity is calculated in a 1D model with curvature. We concentrate on the role of photoionization mechanism in the propagation of the streamer ionization front, the other important mechanisms being electron drift and electron diffusion. The results indicate, in particular, that the effect of photoionization on the streamer velocity for both positive and negative streamers is mostly determined by the photoionization length, with a weaker dependence on the amount of photoionization, and that the velocity is decreased for positive curvature, i.e., convex fronts. These results are used in a fractal model in which the front propagation velocity is simulated as the cluster growth probability [Niemeyer et al, 1984, doi:10.1103/PhysRevLett.52.1033]. Monte Carlo simulations of the cluster growth for various ratios of background electric field E to the breakdown field Eb show that the emerging transverse size of the streamers is of the order of the photoionization length, and at the larger scale the streamer structure is a fractal similar to the one obtained in a diffusion-limited aggregation (DLA) system. In the absence of electron attachment (Eb = 0), the fractal dimension is the same (D ˜ 1.67) as in the DLA model, and is reduced, i.e., the fractal has less branching, for Eb > 0.
Diphoton resonance from a warped extra dimension
Bauer, Martin; Hörner, Clara; Neubert, Matthias
2016-07-01
We argue that extensions of the Standard Model (SM) with a warped extra dimension, which successfully address the hierarchy and flavor problems of elementary particle physics, can provide an elegant explanation of the 750 GeV diphoton excess recently reported by ATLAS and CMS. A gauge-singlet bulk scalar with {O} (1) couplings to fermions is identified as the new resonance S, and the vector-like Kaluza-Klein excitations of the SM quarks and leptons mediate its loop-induced couplings to photons and gluons. The electroweak gauge symmetry almost unambiguously dictates the bulk matter content and hence the hierarchies of the Sto γ γ, W W,ZZ,Zγ, toverline{t} and dijet decay rates. We find that the S → Zγ decay mode is strongly suppressed, such that Br( S → Zγ) /Br( S → γγ) Kaluza-Klein towers of fermion states converge and can be calculated in closed form with a remarkably simple result. Reproducing the observed pp → S → γγ signal requires Kaluza-Klein masses in the multi-TeV range, consistent with bounds from flavor physics and electroweak precision observables.
Anomalous dimensions and non-gaussianity
Energy Technology Data Exchange (ETDEWEB)
Green, Daniel; Lewandowski, Matthew; Senatore, Leonardo; Silverstein, Eva; Zaldarriaga, Matias
2013-10-01
We analyze the signatures of inflationary models that are coupled to interacting field theories, a basic class of multifield models also motivated by their role in providing dynamically small scales. Near the squeezed limit of the bispectrum, we find a simple scaling behavior determined by operator dimensions, which are constrained by the appropriate unitarity bounds. Specifically, we analyze two simple and calculable classes of examples: conformal field theories (CFTs), and large-N CFTs deformed by relevant time-dependent double-trace operators. Together these two classes of examples exhibit a wide range of scalings and shapes of the bispectrum, including nearly equilateral, orthogonal and local non-Gaussianity in different regimes. Along the way, we compare and contrast the shape and amplitude with previous results on weakly coupled fields coupled to inflation. This signature provides a precision test for strongly coupled sectors coupled to inflation via irrelevant operators suppressed by a high mass scale up to ~ 103 times the inflationary Hubble scale.
Emergent fuzzy geometry and fuzzy physics in $4$ dimensions
Ydri, Badis; Khaled, Ramda
2016-01-01
A detailed Monte Carlo calculation of the phase diagram of bosonic IKKT Yang-Mills matrix models in three and six dimensions with quartic mass deformations is given. Background emergent fuzzy geometries in two and four dimensions are observed with a fluctuation given by a noncommutative $U(1)$ gauge theory very weakly coupled to normal scalar fields. The geometry, which is determined dynamically, is given by the fuzzy spheres ${\\bf S}^2_N$ and ${\\bf S}^2_N\\times{\\bf S}^2_N$ respectively. The three and six matrix models are in the same universality class with some differences. For example, in two dimensions the geometry is completely stable, whereas in four dimensions the geometry is stable only in the limit $M\\longrightarrow \\infty$, where $M$ is the mass of the normal fluctuations. The behavior of the eigenvalue distribution in the two theory is also different. We also sketch how we can obtain a stable fuzzy four-sphere ${\\bf S}^2_N\\times{\\bf S}^2_N$ in the large $N$ limit for all values of $M$ as well as mo...
Collider Implications of Multiple Non-Universal Extra Dimensions
Ghavri, R; Nandi, S
2006-01-01
We consider multiple TeV scale extra compact dimensions in an asymmetric string compactification scenario in which the SM gauge bosons can propagate into the TeV scale extra dimensions while the SM fermions are confined to the usual SM D3 brane. We calculate the contributions that the KK excitations of the gluons make to the multijet cross sections in proton proton collisions at the LHC energy. At very high pT, the dijet signal will either be enhanced significantly due to virtual g star exchanges or place a lower bound on the compactification scale of about 8 TeV. We find that the dijet signal is very sensitive to three parameters: the compactification scale, the string scale, and the number of extra dimensions. Thus, although the dijet signal is much more sensitive to KK effects, the dijet signal alone does not provide sufficient information to deduce the number of extra dimensions nor the compactification scale. However, the three jet signal, which is not sensitive to the string scale, can be analyzed in co...
The Many Alternative Faces of Macrophage Activation.
Directory of Open Access Journals (Sweden)
David A. Hume
2015-07-01
Full Text Available Monocytes and macrophages provide the first line of defense against pathogens. They also initiate acquired immunity by processing and presenting antigens and provide the downstream effector functions. In large gene expression datasets from multiple cells and tissues, it is possible to identify sets of genes that are co-regulated with the transcription factors that regulate them. In macrophages, they include lineage-specific genes, interferon-responsive genes, early inflammatory genes, and those associated with endocytosis. Macrophages enter tissues and alter their function to deal with a wide range of challenges related to development and organogenesis, tissue injury, malignancy, sterile or pathogenic inflammatory stimuli. These stimuli alter gene expression to produce activated macrophages that are better equipped to eliminate the cause of their influx, and to restore homeostasis. Activation or polarization states of macrophages have been classified as classical and alternative or M1 and M2. These proposed states of cells are not supported by large-scale transcriptomic data, including macrophage-associated signatures from large cancer tissue datasets, where the supposed markers do not correlate with other. Individual macrophage cells differ markedly from each other, and change their functions in response to doses and combinations of agonists and time. The most studied macrophage activation response is the transcriptional cascade initiated by the TLR4 agonist lipopolysaccharide (LPS. This response is reviewed herein. The network architecture is conserved across species, but many of the target genes evolve rapidly and differ between mouse and human. There is also considerable divergence in the sets of target genes between mouse strains, between individuals and in other species such as pigs. The data and publication deluge related to macrophage activation requires the development of new analytical tools, and ways of presenting information in an
International Nuclear Information System (INIS)
We investigate the many-body level density ρMB for fermion and boson gases. We establish its behavior as a function of the temperature and the number of particles. We deal with correction terms due to finite number of particles effects for ρMB: for fermions, it seems that it exists only one behavior. We propose a semiclassical expression of ρMB for two types of particles with an angular momentum. It is decomposed into a smooth part coming from the saddle point method plus corrective terms due to the expansion of the number of partitions for two types of particles and an oscillating part coming from the fluctuations of the single-particle level density. Our model is validated by a numerical study. For the case of the atomic nucleus, the oscillating part of ρMB is controlled by a temperature factor which depends on the chaotic or integrable nature of the system and on the fluctuation of the ground state energy. This leads to consider in more detail this last quantity. For an isolated system, we give the general expression of the mean value for fixed potentials. We treat the self-bound system case through the example of the three dimensional harmonic oscillator (3DHO). Furthermore we study the oscillating part of ρMB for bosons in the low temperature regime for billiards and for isotropic 3DHO. We note the oscillations disappear leading to a power law correction. In the case of the isotropic 3DHO, these corrections have the same order of magnitude as the smooth part. In the same way, for the high temperature regime we show the oscillating part of ρMB is exponentially negligible compared to the smooth part. (author)
How many carbonic anhydrase inhibition mechanisms exist?
Supuran, Claudiu T
2016-01-01
Six genetic families of the enzyme carbonic anhydrase (CA, EC 4.2.1.1) were described to date. Inhibition of CAs has pharmacologic applications in the field of antiglaucoma, anticonvulsant, anticancer, and anti-infective agents. New classes of CA inhibitors (CAIs) were described in the last decade with enzyme inhibition mechanisms differing considerably from the classical inhibitors of the sulfonamide or anion type. Five different CA inhibition mechanisms are known: (i) the zinc binders coordinate to the catalytically crucial Zn(II) ion from the enzyme active site, with the metal in tetrahedral or trigonal bipyramidal geometries. Sulfonamides and their isosters, most anions, dithiocarbamates and their isosters, carboxylates, and hydroxamates bind in this way; (ii) inhibitors that anchor to the zinc-coordinated water molecule/hydroxide ion (phenols, carboxylates, polyamines, 2-thioxocoumarins, sulfocoumarins); (iii) inhibitors which occlude the entrance to the active site cavity (coumarins and their isosters), this binding site coinciding with that where CA activators bind; (iv) compounds which bind out of the active site cavity (a carboxylic acid derivative was seen to inhibit CA in this manner), and (v) compounds for which the inhibition mechanism is not known, among which the secondary/tertiary sulfonamides as well as imatinib/nilotinib are the most investigated examples. As CAIs are used clinically in many pathologies, with a sulfonamide inhibitor (SLC-0111) in Phase I clinical trials for the management of metastatic solid tumors, this review updates the recent findings in the field which may be useful for a structure-based drug design approach of more selective/potent modulators of the activity of these enzymes. PMID:26619898
Progestin-only injectables offer many advantages.
Finger, W R
1995-06-01
Progestin-only injectables are among the most effective and safe of all contraceptives, yet they are not widely used in many countries. This limited use is in part due to a lack of accurate information about health concerns, inadequate counseling for users about managing side effects, and their limited availability. Where they are available, progestin-only injectables rapidly become one of the preferred methods. Depot-medroxyprogesterone acetate (DMPA) and norethindrone enanthate (NET-EN) are the two progestin-only injectables in use worldwide. The former drug is sold under the brand name Depo-Provera, and the latter as Noristerat. DMPA is delivered in a water-based, crystalline suspension and absorbed gradually by the body. The normal injection of 150 mg is intended to be administered every three months, but contraceptive protection continues for an additional two weeks to provide a grace period for women who are late receiving their next injection. NET-EN is an oily solution which requires a larger needle than DMPA for injection. A 200 mg injection of NET-EN is usually administered every two months. Both of these safe, highly effective drugs are injected in either the upper arm or buttocks. DMPA and NET-EN can be distributed easily in nonclinical settings where nonphysicians can provide them to clients. The main disadvantage of the method is the disruption of the menstrual cycle, but that is generally not a serious medical problem. Focusing mainly upon DMPA, this article includes discussion of menstrual irregularity, the reduced risk of endometrial cancer among DMPA users, and method availability. PMID:12289828
Moving into the third dimension
Alizée Dauvergne
2010-01-01
One detail at a time, digital 3-D models of CERN’s various machines are being created by the Integration Section in the Machines & Experimental Facilities Group (EN/MEF) . The work, which requires painstaking attention to detail on a colossal scale, facilitates improvements to existing accelerators and the design of new machines in the future. Virtual representation of the LHC A complete digital mockup of the LHC in three dimensions already exists, including of course the tunnel, the machine systems including magnets and vacuum chambers, but also all of the various services such as cable ladders, piping systems and access control and so on. Only the colour and the texture of the surfaces betray that it is a mockup and not the real thing! The mockup of LINAC4 is finished too. The mockups for the SPS, ISOLDE and the entire PS complex, including transfer lines, are still being created. “Creating these 3-D mockups will allow us to work on forthcoming machine improvements, esp...
Contagion Shocks in One Dimension
Bertozzi, Andrea L.; Rosado, Jesus; Short, Martin B.; Wang, Li
2015-02-01
We consider an agent-based model of emotional contagion coupled with motion in one dimension that has recently been studied in the computer science community. The model involves movement with a speed proportional to a "fear" variable that undergoes a temporal consensus averaging based on distance to other agents. We study the effect of Riemann initial data for this problem, leading to shock dynamics that are studied both within the agent-based model as well as in a continuum limit. We examine the behavior of the model under distinguished limits as the characteristic contagion interaction distance and the interaction timescale both approach zero. The limiting behavior is related to a classical model for pressureless gas dynamics with "sticky" particles. In comparison, we observe a threshold for the interaction distance vs. interaction timescale that produce qualitatively different behavior for the system - in one case particle paths do not cross and there is a natural Eulerian limit involving nonlocal interactions and in the other case particle paths can cross and one may consider only a kinetic model in the continuum limit.
Extra dimensions at particle colliders
Energy Technology Data Exchange (ETDEWEB)
Dvergsnes, Erik Wolden
2004-08-01
This thesis consists of an introduction where we consider different aspects of theories involving extra dimensions, together with four research publications (Papers I-IV) attached at the end. The introductional chapters should serve as background material for better understanding the models on which the articles are based. In Chap. 4 we also present some plots not included in the papers. The topic of Papers I-III is graviton induced Bremsstrahlung. In Paper I we consider the contribution to this process from graviton exchange through gluon-gluon fusion at the LHC, compared to the QED background. Only final-state radiation is considered in Paper I, whereas in Paper II we extend this work to include also the quark-antiquark annihilation with graviton exchange, as well as initial-state radiation for both graviton and Standard Model exchange. Paper III is a study of graviton-induced Bremsstrahlung at e{sup +}e{sup -} colliders, including both initial- and final-state radiation. Paper IV is devoted to a study of the center-edge asymmetry at hadron colliders, an asymmetry which previously had been studied for e{sup +}e{sup -} colliders. The center-edge asymmetry can be used as a method of distinguishing between spin-1 and spin-2 exchange, something which will be of major importance if a signal is observed.
Higgs Bosons in Extra Dimensions
Quiros, Mariano
2015-01-01
In this paper, motivated by the recent discovery of a Higgs-like boson at the LHC with a mass m_H\\simeq 126 GeV, we review different models where the hierarchy problem is solved by means of a warped extra dimension. In the Randall-Sundrum model electroweak observables provide very strong bounds on the mass of KK modes which motivates extensions to overcome this problem. Two extensions are briefly discussed. One particular extension is based on the deformation of the metric such that it strongly departs from the AdS_5 structure in the IR region while it goes asymptotically to AdS_5 in the UV brane. This model has the IR brane close to a naked metric singularity (which is outside the physical interval) characteristic of soft-walls constructions. The proximity of the singularity provides a strong wave-function renormalization for the Higgs field which suppresses the T and S parameters. The second class of considered extensions are based on the introduction of an extra gauge group in the bulk such that the custod...
Exploring Extra Dimensions in Spectroscopy Experiments
Institute of Scientific and Technical Information of China (English)
LUO Feng; LIU Hong-Ya
2006-01-01
@@ We propose an idea in spectroscopy to search for extra spatial dimensions as well as to detect the possible deviation from Newton's inverse-square law at small scale, and we take high-Z hydrogenic systems and muonic atoms as illustrations. The relevant experiments might help to explore a more than two extra dimensions scenario in the brane world model proposed by Arkani-Hamed, Dimopoulos, Dvali (ADD) and to set constraints for fundamental parameters such as the size of extra dimensions.
Spectral dimension flow on continuum random multigraph
Giasemidis, Georgios; Zohren, Stefan
2012-01-01
We review a recently introduced effective graph approximation of causal dynamical triangulations (CDT), the multigraph ensemble. We argue that it is well suited for analytical computations and that it captures the physical degrees of freedom which are important for the reduction of the spectral dimension as observed in numerical simulations of CDT. In addition multigraph models allow us to study the relationship between the spectral dimension and the Hausdorff dimension, thus establishing a link to other approaches to quantum gravity
The Fractal Dimension of River Length Based on the Observed Data
Directory of Open Access Journals (Sweden)
Ni Zhihui
2013-01-01
Full Text Available Although the phenomenon that strictly meets the constant dimension fractal form in the nature does not exist, fractal theory provides a new way and means for the study of complex natural phenomena. Therefore, we use some variable dimension fractal analysis methods to study river flow discharge. On the basis of the flood flow corresponding to the waterline length, the river of the overall and partial dimensions are calculated and the relationships between the overall and partial dimensions are discussed. The law of the length in section of Chongqing city of Yangtze River is calibrated by using of variable fractal dimension. The results conclude that it does express a second-order accumulated variable-dimensional fractal phenomenon, and the dimension can reflect the degree of the river; the greater dimension, the more the river bend. It has different dimensions at a different location in the same river. In the same river, the larger dimension, the worse flow discharge capacity of the river and the more obvious of the flood will be on the performance.