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A general technique for decoupling of equations describing the evolution of different automatic control systems was obtained. At the beginning, some auxiliary square matrixes are drawn up, and then the problem of their simultaneous transforming to the block-diagonal form is solved. The same approach is applied for matrix macroeconomic models decoupling. [ABSTRACT FROM AUTHOR]

The need to continually improve on existing numerical techniques for solving non-linear differential equations that model some real life phenomena that cannot be explained analytically cannot be overstated. In previous studies, the spectral local linearization method (SLLM)) has been shown to be reliable and efficient in dealing with non-linear systems of ordinary and partial differential equations. However, the SLLM is not free from limitations which require further investigation. This study intends to overcome those limitations by introducing a new numerical technique, hereinafter referred to as the paired quasilinearization method (PQLM), that will improve on the speed of convergence of the SLLM. The concept of the PQLM involves solving systems of differential equations in pairs using both coupling and decoupling approaches. A comparative study is carried out on the PQLM and the SLLM by solving a system of ordinary differential equations. Comparison is made on the performance of the methods in terms of solution error, convergence rate, computational efficiency, and residual error norm analysis. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous motor (PMSM) is a nonlinear, strong coupling, multivariable complex object, and transformation decoupling can solve the coupling problem of permanent magnet synchronous motor. This paper gives a permanent magnet synchronous motor (PMSM) mathematical model, introduces the permanent magnet synchronous motor vector control coordinate transformation in the process of modal matrix inductance matrix transform through the matrix related knowledge of different coordinates of diagonalization, which makes the coupling between the independent, realize the control of motor current and excitation the torque current coupling separation, and derived the coordinate transformation matrix, the thought to solve the coupling problem of AC motor. Finally, in the Matlab/Simulink environment, through the establishment and combination between the PMSM ontology, coordinate conversion module, built the simulation model of permanent magnet synchronous motor vector control, introduces the model of each part, and analyzed the simulation results. [ABSTRACT FROM AUTHOR]

This paper explores so called "View-Upload Decoupling scheme" which strictly decouples data to what peer uploads and what it personally views. It is based on the split of downloaded user data streams into two types: the stream of the chosen TV channel and the stream (one or more) of the other TV channel, exclusively, to deliver it to other users. We developed a method for calculating one of the key QoS characteristics in P2P streaming network - the probability of universal streaming for each channel and a system-wide universal streaming across all channels. The statistical probability results of universal streaming for the VUD scheme compared to the traditional redistributing ISO scheme are presented. [ABSTRACT FROM AUTHOR]

Otoacoustic emissions (OAEs) evoked by pure tones lock onto the phase of the stimulus at the place of their generation in the cochlea. The effects of phase transitions in a pure tone stimulus on OAEs have not been investigated. By combining responses to pure tones with smooth phase transitions, phase-evoked residual responses (PERRs) were extracted from nine normal-hearing subjects. Five of them had PERRs in at least 18 of 36 parameter conditions expected to yield a response. PERRs do not have a straightforward dependence on stimulus parameters, but their general prevalence suggests a temporary decoupling between stimulus and OAE phase - between 5 and 10 ms. Since the stimulus is narrow in the frequency domain, the PERR may reflect the dynamic behavior of localized regions of OAE generators. [ABSTRACT FROM AUTHOR]

We present a factorization framework that takes into account the production of heavy quarks through gluon splitting in the thrust distribution for e+e- → hadrons. The explicit factorization theorems and some numerical results are displayed in the dijet region where the kinematic scales are widely separated, which can be extended systematically to the whole spectrum. We account for the necessary two-loop matrix elements, threshold corrections, and include resummation up to N3LL order.We include nonperturbative power corrections through a field theoretical shape function, and remove the ϐ(ΔQCD) renormalon in the partonic soft function by appropriate mass-dependent subtractions. Our results hold for any value of the quark mass, from an infinitesimally small (merging to the known massless result) to an infinitely large one (achieving the decoupling limit). This is the first example of an application of a variable flavor number scheme to final state jets. [ABSTRACT FROM AUTHOR]

We present a factorization framework that takes into account the production of heavy quarks through gluon splitting in the thrust distribution for e+e- →hadrons. The explicit factorization theorems and some numerical results are displayed in the dijet region where the kinematic scales are widely separated, which can be extended systematically to the whole spectrum. We account for the necessary two-loop matrix elements, threshold corrections, and include resummation up to N³LL order. We include nonperturbative power corrections through a field theoretical shape function, and remove the O(ΛQCD) renormalon in the partonic soft function by appropriate mass-dependent subtractions. Our results hold for any value of the quark mass, from an infinitesimally small (merging to the known massless result) to an infinitely large one (achieving the decoupling limit). This is the first example of an application of a variable flavor number scheme to final state jets. [ABSTRACT FROM AUTHOR]

Supersymmetry (SUSY) solves the hierarchy problem by introducing a super partner to each Standard Model(SM) particle. SUSY must be broken in nature, which means the fine-tuning is reintroduced to some level. Natural SUSY models enjoy low fine-tuning by featuring a small super potential parameter μ ~ 125 GeV, while the third generation squarks have mass less than 1.5 TeV. First and second generation sfermions can be at the multi-TeV level which yields a decoupling solution to the SUSY flavor and CP problem. However, models of Natural SUSY have difficulties in predicting a mh at 125 GeV, because the third generation is too light to give large radiative correction to the Higgs mass. The models of Radiative Natural SUSY (RNS) address this problem by allowing for high scale soft SUSY breaking Higgs mass mHu > m0, which leads to automatic cancellation by the Renormalization Group (RG) running effect. Coupled with the large mixing in the stop sector, RNS allows low fine-tuning at 3-10 % level and a 125 GeV SM-like Higgs. RNS can be reached at the LHC, and a linear collider. If the strong CP problem is solved by the Peccei-Quinn mechanism, then RNS accommodates mixed axion-Higgsino cold dark matter, where the Higgsino-like WIMPs, which in this case make up only a fraction of the relic abundance, can be detectable at future WIMP detectors. [ABSTRACT FROM AUTHOR]

The effect of operating an absolute eddy-current (EC) probe at frequencies around its electrical resonance was investigated. A defect signal enhancement phenomenon was observed and characterised. Experimental tests were performed on notch defects in typical aerospace superalloys. An absolute mode EC probe was operated by sweeping through a range of frequencies, in the MHz range, encompassing the electrical resonance of the system. Resonance decoupling above defects results in a signal-to-noise ratio (SNR) peak, within a band of frequencies approaching resonance, of up to 3.7 times that measured at 1MHz. This near electrical resonance signal enhancement (NERSE) phenomenon poses the possibility for a simple operational approach method for improving the sensitivity of conventional eddy-current testing. [ABSTRACT FROM AUTHOR]

The ALOHA [1] code is frequently used as a standard to solve the coupling of lower hybrid grills to the plasma. To remove its limitations on the linear density profile, homogeneous magnetic field and the fully decoupled fast and slow waves in the determination of the plasma surface admittance, we exploit the recently developed efficient full wave code OLGA [2]. There is simple connection between these two codes, namely, the plasma surface admittances used in ALOHA-2D can be expressed as the slowly varying parts of the coupling element integrands in OLGA and the ALOHA coupling elements are then linear combinations of OLGA coupling elements. We developed AOLGA module (subset of OLGA) for ALOHA. An extensive benchmark has been performed. ALOHA admittances differ from AOLGA results mainly for N in the inaccessible region but the coupling elements differ only slightly. We compare OLGA and ALOHA for a simple 10-waveguide grill operating at 3.7 GHz and the linear density profile as it is used in ALOHA. Hence we can detect pure effects of fast and slow waves coupling on grill efficiency. The effects are weak for parameters near the optimum coupling and confirm the ALOHA results validity. We also compare the effect of the plasma surface density and the density gradient on the grill coupling determined by OLGA and ALOHA. [ABSTRACT FROM AUTHOR]

A transport equation is derived and discussed that describes the post-maximum phase of solar energetic particle (SEP) events, when the combination of nearly scatter-free propagation along field lines and magnetic mirroring inside 1AU with back-scatter beyond 1AU reduces both the field-aligned intensity gradient and field-aligned pitch-angle anisotropy to small values, producing a particle "reservoir". The mathematical de-coupling of parallel and transverse propagation is the key element in this description of "reservoir" transport, which also has applications beyond the description of the decay of SEP events. [ABSTRACT FROM AUTHOR]

Slow down of decaying cosmic magnetic fields in QED scalar electrodynamics is obtained. [ABSTRACT FROM AUTHOR]

We briefly describe the 1/Nc expansion method for studying baryon masses. Two approaches of the large Nc excited baryons have been proposed so far. The first one, based on the Hartree picture, treats the baryon as a ground state core and an excited quark and the second one, suggested recently, considers the baryon globally, without decoupling the system. The masses of excited states of mixed orbital symmetry of nonstrange and strange baryons belonging to the lowest [70, -] multiplet are calculated in the 1/Nc expansion to order 1/Nc with the new method which allows to considerably reduce the number of linearly independent operators entering the mass formula. The status of the resonance Λ(1405) is discussed. [ABSTRACT FROM AUTHOR]

Both regular (the zero-momentum ghost dressing function not diverging), also named decoupling, and critical (diverging), also named scaling, Yang-Mills propagators solutions can be obtained by analyzing the low-momentum behaviour of the ghost propagator Dyson-Schwinger equation (DSE) in Landau gauge. The asymptotic expression obtained for the regular or decoupling ghost dressing function up to the order O(q2) fits pretty well the low-momentum ghost propagator obtained through the numerical integration of the coupled gluon and ghost DSE in the PT-BFM scheme. Furthermore, when the size of the coupling renormalized at some scale approaches some critical value, the PT-BFM results seems to tend to the the scaling solution as a limiting case. This critical value of the coupling is compared with the lattice estimate for the Yang-Mills QCD coupling and the latter is shown to lie much above the former. [ABSTRACT FROM AUTHOR]

The effects of free stream turbulence on non-premixed flames are numerically analyzed. The Spalding eddy dissipation mathematical model is used to control the reaction rate by the large-eddy time scale. The turbulence energy production and dissipation rates are simulated by the κ—[variant_greek_epsilon] turbulence model in order to investigate the dependence of the combustion properties on free stream turbulence. The reacting NS equations were spatially discretized and solved through a finite volume scheme and a decoupled pressure-velocity approach, respectively. The flame was assumed to be steady-state, two dimensional and axisymmetric. The reported results include the velocity, temperature and turbulent reaction rate along the flame propagation field. It is found that the increase of free stream turbulence intensity reduces the reaction zone significantly, hence, induces the flame extinction process. [ABSTRACT FROM AUTHOR]

Fission of highly excited nuclei is affected by the viscose character of the system motion in deformation coordinates as is reported for very heavy nuclei with Z≥90. The long-time-scale fission was proved for such systems formed in heavy-ion induced reactions. The overdamped diabatic motion may influence also fission of the spallation-residue products in reactions with protons at intermediate energy. In the present work, the experimental results on blocking lifetime experiments are analyzed together with the independent data on fission-to-spallation ratios for medium-mass targets. Cross examination of the fission probability, time-scale, and pre-fission neutron multiplicity allows a new conclusion on fission mechanism. The novel approach is specified for estimate of the characteristic fission time and for the consistent interpretation of whole set of experimental results. The standard statistical approach fails for understanding of them without contradictions, though some partial data at restricted range of the encounter parameters could be described, as known from previous publications. [ABSTRACT FROM AUTHOR]

The effect of magnetic (Pr) and non-magnetic (Ca) chemical substitutions on the intragranular critical current, Jintra,c, in polycrystalline Y1-x-yPrxCayBa2Cu3O7-δ samples is studied. In principle two factors limit the Jintra,c: decoupling critical current density J0∼Hc/λ (Hc—thermodynamical critical field, λ-London penetration depth) and pinning force. It is shown that at 4.2 K and low concentration (x = 0.05, y = 0 and x = 0, y = 0.025) both substitutions are almost equally effective and lead to Jintra,c higher than that for the non-substituted sample. This is a result of generated nanometric substitutional defects, increasing the pinning in both cases. The non-magnetic, low valence Ca2+ substitution increases the carriers and leads to small overdoping, while the magnetic (Pr3+) substitution only slightly deteriorates decoupling current. At high concentrations (x = 0.20, y = 0 and x = 0, y = 0.25) Jintra,c, decreases in comparison with the non-substituted sample due to decoupling current suppression in both cases. It is also established that low Pr concentration gives the highest Jc,intra, at fields higher than 1 T when the temperature is raised to 20 K. [ABSTRACT FROM AUTHOR]

We work out the decoupling problem and hydrodynamic analysis for the sound mode in charged AdS black hole and calculate the sound velocity, the charge susceptibility and the electrical conductivity. We find that Einstein relation among the conductivity, the diffusion constant and the susceptibility holds exactly. [ABSTRACT FROM AUTHOR]

The reference ITER ICRH load resilient matching system uses four 3dB hybrid power splitters. It is proposed to use a “double stub” tuner (DST) configuration for the matching on the reference load and a decoupling system placed between the antenna plug and the matching system to reduce the mutual coupling effects and also to actively control the array current spectrum while requesting the same forward power from all 4 power sources. The paper analyzes (i) the optimization of the matching layout e.g. by varying the distance between the stubs and by the use of two capacitors taking into account the role of the decouplers on the matching requirements; (ii) the practical realization of the decouplers and their insertion into the circuit; (iii) the requests in voltage and current capabilities in the different parts of the system. The paper presents solutions for saving space and to decrease the ratings of the components. The computations are done with the array loading simulated by the TOPICA matrix. [ABSTRACT FROM AUTHOR]

Elastic and inelastic scattering of the lightest supersymmetric particle (LSP) off nuclei is discussed. The LSP dark-matter detection rates for the stable iodine, xenon and cesium detectors are derived. The parameters of the supersymmetric theory are decoupled from the nuclear structure by tabulating a set of nuclear-structure coefficients. These coefficients are calculated by using the nuclear shell model in the valence space containing the 2s, 1d, 0g7/2, and 0h11/2 single-particle orbitals. A realistic effective two-nucleon interaction based on the Bonn-CD G-matrix is used. By using fitted nuclear gyromagnetic factors we successfully reproduce the relevant spectroscopic data on magnetic moments and M1 decays in the discussed nuclei. [ABSTRACT FROM AUTHOR]

The interpretation of quantum mechanics has been disputed ever since the advent of the theory in the 1920’s. Famous are the discussions over long time between Einstein and Bohr. Einstein refused to accept the so-called Copenhagen interpretation, where the wave function collapses at a measurement and where the outcome of the measurement is essentially accidental (“God does not play dice”). Alternative interpretations have appeared, but the Copenhagen school has dominated the thoughts throughout the decades. One interesting interpretation was formulated in 1957 by Hugh Everett at Princeton, a student of John Wheeler, which abandons the wave-function collapse. In this model the universe is governed entirely by the Schrödinger equation, which does not allow for any collapse. In Everett’s model after a measurement the wave function is separated into different branches that do not interact. This model was left unnoticed for long time until Bryce DeWitt took it up in 1970 and termed it “Many-Worlds Interpretation”, a term that in some sense is misleading. Everett’s model is incomplete, and it was later supplemented by the theory of decoherence, which explains how the different branches decouple as a result of the interaction with the environment. This extended model has in recent years gained increased respect, and some believe that it is the only model made available so far that is fully consistent with quantum mechanics. This interpretation can also shed some light on the development of the universe and, in particular, on the so-called Anthropic principle, which puts human beings at the center of the development. [ABSTRACT FROM AUTHOR]

We study the random close packing of a binary mixture of spheres and rod-like particles (spherocylinders) by the mechanical contraction computer simulation. We investigate the universality in packing of near-spheres by monitoring the position and the value of the maximum in the mixture packing density as a function of the mixture composition and the rod aspect ratio. We find that independently of the mixture composition the particles pack more efficiently/densely as the rod aspect ratio is perturbed slightly from zero and the maximum density is always reached at one unique rod aspect ratio of about 0.45. The dependence of the value of the maximum packing fraction on the mixture composition (the relative rod volume fraction) is linear, exhibiting some ideality in packing of near-spheres. This counter-intuitive finding suggests that even for high rod concentrations in a rod-sphere mixture the packing is governed by local contacts between the neighboring particles, which is usually observed for dilute colloidal suspensions and granular gases, where there is no correlation between the particles. The plausible explanation for this intriguing behavior is that the correlations between the particles are completely lost in the range of distances of several particle diameters, which can be originated from the decoupling of the orientational and translational degrees of freedom of the nearly spherical rods. This gives rise to the universality and locality of random close packing of the rod-sphere mixtures. [ABSTRACT FROM AUTHOR]

Our previous work [1] showed that if a primordial magnetic field (PMF) was present during photon decoupling and afterward, massive neutrinos affect all modes of the CMB. This is because of the compensation of anisotropic stress between the neutrinos and the PMF. In order to study the observability of this new effect, we need careful analysis of the passive mode [2] generated by the PMF. Here, we focus on the polarization of the CMB and study the observability of the finite neutrino mass effect. [ABSTRACT FROM AUTHOR]

We suggest a simple extension of the electroweak group, SU(2)L×U(1)Y×U(1)B–L, where the breaking of U(1)B–L symmetry provides masses for right handed neutrinos, N, at an acceptable range for them to be Dark Matter (DM). We study the contributions to Mo\ller and Bhabha scattering due to B–L neutral boson to constrain its gauge coupling. We analize N decay rates to determine the number of families that should be considered as DM candidates. The decoupling temperature between active and sterile neutrinos is also calculated. [ABSTRACT FROM AUTHOR]

Image moments provide an important class of image features used for image-based visual servo control. Perspective zeroth and first order image moments provide a quasi linear and decoupled link between the image features and the translational degrees of freedom. Spherical first-order image moments have the additional desirable passivity property. They allow to decouple the position control scheme from the rotation dynamics. This property is suitable to control an under-actuated aerial vehicle such as a quadrotor. In this paper a range of kinematic control laws using spherical image moments and perspective image moments are experimented on a quadrotor aerial vehicle prototype. The task considered is to reach a desired position with respect to a specified target. Three control schemes show excellent performances in practice whereas each one has different theoretical properties. [ABSTRACT FROM AUTHOR]

We study double Higgs-strahlung production at the future Linear Collider in the framework of the Two Higgs Doublet Models through the following channels: e+e-→[uppercase_phi_synonym]i[uppercase_phi_synonym]jZ, [uppercase_phi_synonym]i = h °,H °,A °. All these processes are sensitive to triple Higgs couplings. Hence observations of them provide information on the triple Higgs couplings that help reconstructing the scalar potential. We discuss also the double Higgs-strahlung e+e-→h °h °Z in the decoupling limit where h ° mimics the SM Higgs boson. [ABSTRACT FROM AUTHOR]

We demonstrate that non-equilibrium unbinding simulations can be used to accurately estimate equilibrium binding affinities. Utilizing the FKBP protein bound to two different ligands we estimate the absolute binding affinities within less than 1.0 kcal/mol of the experimental values. The methodology is straight-forward, requiring no modification to many modern molecular simulation packages. The approach makes use of a physical pathway, eliminating the need for complicated alchemical decoupling schemes. These results suggest that non-equilibrium simulation could provide a viable means to accurately estimate protein-ligand binding affinities. [ABSTRACT FROM AUTHOR]

We investigate the dynamics of inflation models driven by multiple, decoupled scalar fields and calculate the Hubble parameter and the amplitude of the lightest field at the end of inflation. The results are very simple and similar to those of the single field inflation, mainly depending on the underlying spectrum of the masses. The mass distribution is heavily constrained by the power spectrum of density perturbations P and the spectral index ns. The overall mass scale gives the amplitude of P and ns is affected by the number of fields and the spacing between masses in the distribution. The drop-out effect of the massive fields makes the perturbation spectrum typically redder than the single field inflation spectrum. We illustrate this using two different mass distributions. [ABSTRACT FROM AUTHOR]

According to the deficiency of the prior modeling methods on main-pipeline system, the paper advances a near distributed modeling way based on subsection, combination and delamination for parallel coursing units and main-pipeline system to fully show its distributed dynamics by an easy-simulated mode of expression. Firstly, a principle is established to plot out the main-pipeline into some short pipe-sections between each pair of fountain/confluent points. Secondly, a near distributed decoupling transfer function matrix model without steady error for each pipe-section is built by rationally approximate deduction and then joined with the dynamic models of the fountain/confluent at the two ends of the pipe-section to form the near distributed model of each subsection. Finally, a smooth arithmetic is adopted to joint all the conterminous subsections into a whole system model. The modeling method above decreases the dimension of matter space and integrates more influence factors on the system dynamic characteristics into the built model, such as pipe length, diameter and the thermodynamics of working fluid, so it more particularly reflects the distributed dynamic characteristics of a multifountain-and-multiconfluent network system of steam main-pipeline and parallel coursing units than before, and can act well as the simulated research object for advanced main-pipeline system control arithmetic and distributed control technology or even validates them. Some simulation experiments have been done and produced good results to prove the validity of the modeling method. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Within the scope of this article a decoupling algorithm to reduce computing time in Finite Element Analyses of incremental forming processes will be investigated. Based on the given position of the small forming zone, the presented algorithm aims at separating a Finite Element Model in an elastic and an elasto-plastic deformation zone. Including the elastic response of the structure by means of model simplifications, the costly iteration in the elasto-plastic zone can be restricted to the small forming zone and to few supporting elements in order to reduce computation time. Since the forming zone moves along the specimen, an update of both, forming zone with elastic boundary and supporting structure, is needed after several increments. The presented paper discusses the algorithmic implementation of the approach and introduces several strategies to implement the denoted elastic boundary condition at the boundary of the plastic forming zone. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Treating the minimal supersymmetric standard model as an effective theory, we study the implications of having dimension-five operators in the superpotential for flavor- and CP-violating processes, exploiting the linear decoupling of observable effects with respect to the new threshold scale Λ. We show that the assumption of weak-scale supersymmetry, when combined with the stringent limits on electric dipole moments and lepton-flavor-violating processes, provides sensitivity to Λ as high as 107–109 GeV. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Space nuclear Reactor Power Systems (SRPSs) are being developed to meet electrical power requirements for NASA’s planetary exploration missions early next decade. In addition to enjoying some degree of autonomy, these systems need to operate reliably through the end of the mission, which could not be realized solely through a redundancy in the reactor’s coolant loop. Besides increasing the total system mass, such hardware redundancy does not eliminate a single-point failure in the reactor and subsequent loss of coolant. This paper presents three concepts of the liquid metal cooled. Sectored, Compact Reactor (SCoRe) for the avoidance of single-point failure. The SCoRe-S, ScoRe-M, and SCoRe-L concepts are for small, medium, and large reactor cores, covering a wide range of electrical power requirements, from 10’s of kWe to a few MWe. As a common feature in all SCoRe concepts, the reactor core is divided into six sectors that are neutronically coupled but thermal-hydraulically decoupled. The dividers of the sectors are liquid metal heat pipes, which facilitate cooling a sector experiencing a Loss of Coolant (LOC) by passively transporting the fission power generated in it to the two adjacent sectors without losing the mission. At the same time, the fission power of the reactor is reduced to avoid overheating the fuel in the sector experiencing a LOC. The SCoRe concepts have compact, hexagonal cores surrounded by a relatively thick (10 cm minimum) BeO reflector and axial BeO reflector that is 4 cm thick. The SCoRe is placed directly in front of the radiation shield, thus reducing the shield mass and that of the power system. In SCoRe-S cores, the UN fuel pins are arranged in a triangular lattice while in the SCoRe-M and SCoRe-L cores, the UN fuel pins arranged in a triangular lattice are assembled in 19-pin and 37-pin shrouded bundles, respectively. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]

In this contribution we present an overview of experimental data on dynamic crossover in various molecular and polymeric liquids, van-der-Waals, ionic, covalent and hydrogen bonded systems. We demonstrate that the structural relaxation time τ measured at TD has nearly the same value, τ(TD)∼10-7±1 sec, for different glass-forming systems. We speculate that decoupling of various relaxation processes observed at TD might be the reason for failure of time-temperature superposition known for polymers. We demonstrate that the dynamic transition in biological macromolecules follows the scenario known for the dynamic crossover in glass forming liquids. Moreover, our analysis reveals that TD observed in dynamics of proteins is close to TD of pure solvents. We speculate that the solvent’s dynamic crossover controls the dynamic transition of proteins. In other words, proteins and DNA are “slaves” of a solvent and this might open ways for a control of their biochemical activity. © 2004 American Institute of Physics [ABSTRACT FROM AUTHOR]

We present two new algorithms that universally construct a quantum circuit approximat-ing a controlled-U(t) up to a global phase factor of U(t), denoted by AøU(t), where U(t) = e-iHt is the unitary evolution operator of an unknown Hamiltonian H of the system, and is given as a black box with tunable parameter t. We show that it is possible to approximately construct AøU(t) with arbitrarily high accuracy. This algorithm is based on the dynamical decoupling effect [1]. If another black box consisting of a time-inverted version of U(t), namely U(-t), is also available we can implement AøU(t) exactly with arbitrarily high success probability. This algorithm is based on the quantum Zeno effect. [ABSTRACT FROM AUTHOR]

Both regular (the zero-momentum ghost dressing function not diverging), also named decoupling, and critical (diverging), also named scaling, Yang-Mills propagators solutions can be obtained by analyzing the low-momentum behaviour of the ghost propagator Dyson-Schwinger equation (DSE) in Landau gauge. The asymptotic expression obtained for the regular or decoupling ghost dressing function up to the order O(q2) fits pretty well the low-momentum ghost propagator obtained through the numerical integration of the coupled gluon and ghost DSE in the PT-BFM scheme. Furthermore, when the size of the coupling renormalized at some scale approaches some critical value, the PT-BFM results seems to tend to the the scaling solution as a limiting case. [ABSTRACT FROM AUTHOR]

We investigate the two-dimensional electron gas and the discrete level under the magnetic field by numerically studying the two-dimensional tight-binding lattice and the discrete level coupled system. Focusing on the partial charge density, we show that the coupling and decoupling between the two-dimensional tight-binding lattice and the discrete level depends on the applied magnetic field. Moreover, we also discuss the modulation of the charge injection into the inversion layer by the applied magnetic field. [ABSTRACT FROM AUTHOR]

We predict the decoupled superconductivity for the four-layered F′/S′/F″/S″ nanostructure consisting of dirty superconducting (S) and ferromagnetic (F) metals. The predicted hierarchy of critical temperatures is found to manifest itself in its most striking way through arising of different critical temperatures in different superconducting layers S′ and S″. In common case the phase diagram including four different regions is found. Conceptual sketch of the new control nanodevice based on this tetralayer system are proposed. It is shown that they can have up to seven various states. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]